text:
Airborne electronic attackan electronic warfare capabilityinvolves use of aircraft to neutralize, destroy, or temporarily suppress enemy air defense and communications systems, either through destructive or disruptive means. These capabilities are increasingly important and complex as networked systems, distributed controls, and sophisticated sensors become ubiquitous in military equipment, civilian infrastructure, and commercial networks. These technological developments complicate the Department of Defenses ability to exercise control over the electromagnetic spectrum, when necessary, to support U.S. military objectives. Aircraft executing airborne electronic attack missions employ a variety of mission systems, such as electronic jamming pods, and weapons, such as antiradiation missiles and air-launched expendable decoys. These aircraft also rely on aircraft self-protection systems and defensive countermeasures for additional protection.
All four military services within the Department of Defense are separately acquiring new airborne electronic attack systems. Department of Defense investments to develop and procure new and updated airborne electronic attack systems are projected to total more than $17.6 billion from fiscal years 2007 through 2016. With the prospect of slowly growing or flat defense budgets for years to come, the department must get better returns on its weapon system investments and find ways to deliver more capability to the warfighter for less than it has in the past.
GAOs ongoing review of planned airborne electronic attack systems found that the department is developing multiple systems to provide similar capabilities. Opportunities may exist for consolidating some current service-specific acquisition efforts. As GAO reported in March 2011, service-driven requirements and funding processes continue to hinder integration and efficiency and contribute to unnecessary duplication in addressing warfighter needs. In the airborne electronic attack mission area, systems in development may overlapat least to some extentin terms of planned mission tasks. Yet, they are being developed as individual programs by the different services. The table below highlights overlap among four systems being developed to counter irregular warfare[1] threatsone subset of airborne electronic attack. While the host platforms for each system are different, the missions each system performs are similar.
Potential Overlap among Communication Jamming Systems Supporting Ground Forces
System name
Collaborative On-line Reconnaissance Provider Operationally Responsive Attack Link (CORPORAL)
Intrepid Tiger II
Communications Electronic Attack with Surveillance and Reconnaissance (CEASAR)
MQ-9 Reaper Electronic Attack Pod
Service sponsor
Marine Corps
Marine Corps
Air Force
Host platform
RQ-7B Shadow unmanned aerial vehicle
AV-8B fixed wing aircrafta
C-12 fixed wing aircraft
MQ-9 Reaper unmanned aerial vehicle
Mission description
Communications jamming in support of ground forcesb
Communications jamming and surveillance capability in support of ground forces
Denial and disruption of enemy communications systems and improvised explosive devices in support of unit-level ground commanders
Communications and improvised explosive device jamming in support of combatant commander mission needs
Estimated acquisition cost
$54.5 million
$76.8 million
$13.8 millionc
$233.7 million
Source: GAO analysis of Department of Defense data.
aAfter the AV-8B, the Intrepid Tiger II pod will be integrated onto additional aircraft.
bCORPORAL also consists of other technologies that serve broader purposes.
cTotal excludes $26.3 million in funding from the Operations and Maintenance, Army budget account through fiscal year 2013. The Army uses these funds to (1) lease two C-12 aircraft to fly the CEASAR pod and (2) fund aircraft and pod sustainment costs.
According to Department of Defense officials, airborne electronic attack limitations in recent operations, urgent needs of combatant commanders, and the desire to provide ground units with their own locally controlled assets have all contributed to the services decisions to develop their own systems to address irregular warfare threats.
Requirements for most of these irregular warfare systems were derived from Department of Defense urgent needs processesactivities aimed at rapidly developing, equipping, and fielding solutions and critical capabilities to the warfighter in a way that is more responsive to urgent warfighter requests than the departments traditional acquisition procedures. As GAO reported in March 2011, the departments urgent needs processes often lead to multiple entities responding to requests for similar capabilities, resulting in potential duplication of efforts. As military operations in Iraq and Afghanistan wind downand the services evaluate whether to transition their current urgent needs program over to the formal weapon system acquisition processopportunities may exist to better consolidate current program activities, such as the CORPORAL and CEASAR pod systems that are still demonstration programs whose transitions to formal acquisition programs have not yet been determined.
The potential for unnecessary duplication of efforts within the airborne electronic attack area is not limited to irregular warfare systems. Similar issues exist with airborne electronic attack systems designed to counter potential near-peer adversaries.[2] Most notably, both the Air Force and Navy are separately evaluating options for acquiring advanced jamming decoysthe Air Force through an upgrade (referred to as Increment II) to its Miniature Air Launched Decoy-Jammer (MALD-J) program, and the Navy through its planned Airborne Electronic Attack Expendable initiative.
The two services have held discussions with one another about combining efforts toward a joint solutionincluding a meeting between Navy and Air Force requirements offices and acquisition officials in December 2010but they have not reached resolution on a common path forward. According to Navy officials, relatively minor design and software modifications to the Air Forces planned MALD-J Increment II system could produce a system that satisfies both services mission requirements. However, Air Force officials stated that accommodating the Navys mission requirements within the system would increase program costs and delay planned fielding of the Increment II system, essentially rendering the current program unexecutable. Subsequently, Air Force officials stated that unless MALD-J Increment II, as currently configured, sufficiently meets Navy requirements, they do not expect the Navy to have any formal role in the program. In July 2011, the Air Force suspended MALD-J Increment II because of future funding shortfalls. This pause in the program affords an opportunity for continued dialogue between the two services as to potential benefits and drawbacks to the pursuit of a common acquisition solution.
On the other hand, the services have shown in some instances that they can share information across the different efforts. For example, Marine Corps decisions to reuse jammer technologies from CORPORAL for Intrepid Tiger II have driven significant commonality in hardware and software for these systems, which program officials state has reduced technical challenges and produced cost savings.
Pursuing multiple separate acquisition efforts to develop similar capabilities within the airborne electronic attack mission area can lead to insufficient use of resources and may contribute to other warfighting needs going unfilled. Leveraging resources and acquisition efforts across services can simplify developmental efforts, improve interoperability among systems, and decrease operations and support costsoutcomes that position the department to maximize the returns it gets on its airborne electronic attack investments.
[1]Irregular warfare is defined as a violent struggle among state and nonstate actors for legitimacy and influence over the relevant population(s). Irregular warfare favors indirect and asymmetric approaches, though it may employ the full range of military and other capacities, in order to erode an adversarys power, influence, and will.
[2]Potential near-peer adversaries include countries capable of waging large scale conventional war on the United States. These nation-states are characterized as having nearly comparable diplomatic, informational, military, and economic capacity to the United States.
To ensure investments in airborne electronic attack systems are cost-effective and to prevent unnecessary overlap, GAO expects to recommend that the Secretary of Defense
Department of Defense analysis of airborne electronic attack programsboth current and plannedcould reduce duplication of similar acquisition initiatives and improve efficiencies. More analysis is needed by the department to determine the potential for cost savings.
The information contained in this analysis is based on findings from the products listed in the related GAO products section and additional work GAO conducted to be published as a separate product in 2012. GAO reviewed program documentation to identify planned capabilities, technical challenges, and anticipated costs for key systems. GAO also analyzed Department of Defense documents outlining airborne electronic attack-related mission requirements and acquisition needs and reviewed platform-specific capabilities documents, service roadmaps, and budget documents, which together provided insight on the departments overall strategy for acquiring airborne electronic attack capabilities. GAO conducted interviews with relevant Department of Defense officials responsible for managing airborne electronic attack requirements and programs.
See page 336 of the PDF version of this report (appendix III) for a list of the programs GAO identified that may have similar or overlapping objectives, provide similar services or be fragmented across government missions. Overlap and fragmentation may not necessarily lead to actual duplication, and some degree of overlap and duplication may be justified.
GAO provided a draft of this report section to the Department of Defense for review and comment. The department provided technical comments, which were incorporated as appropriate. In its comments, the department noted that the Army and Marine Corps have held high-level discussions to collaborate on the CEASAR, Intrepid Tiger II, and CORPORAL programs. According to the department, discussions to share hardware and software technology are ongoingan arrangement that, if implemented, could result in significant cost avoidancebut talks have not yet yielded a design or set of requirements agreeable to both services. As part of GAOs routine audit work, GAO will track agency actions to address these expected recommendations and report to Congress.
For additional information about this area, contact Michael J. Sullivan at (202) 512-4841 or firstname.lastname@example.com.
Forces in Iraq and Afghanistan have faced significant risks of mission failure and loss of life due to rapidly changing enemy threats. In response, the Department of Defense (DOD) established urgent operational needs processes to rapidly develop, modify, and field new capabilities, such as intelligence, surveillance and reconnaissance (ISR) technology, and counter-improvised explosive devices (IED...
Overlap and fragmentation among government programs or activities can be harbingers of unnecessary duplication. In this report we include 81 areas for consideration drawn from GAO's prior and ongoing work. We present 34 areas where agencies, offices, or initiatives have similar or overlapping objectives or provide similar services to the same populations; or where government missions are fragmente...


text:
Const. Robb Costello would often tell his spouse that no matter what happened to him on the job, he would always come home.
On Friday, the Fredericton officer didn't return.
Instead, police showed up at Jackie McLean's home to tell her the 45-year-old was among four people killed in a shooting that took place in a quiet residential neighbourhood.
"This is the first day he did not come back home," McLean, Costello's common-law partner said. "I am having a really hard time envisioning my life without him."
Fredericton Police Chief Leanne Fitch identified the dead officers — a seasoned warhorse and a recent recruit — as Lawrence Robb Costello, 45, a husband with four children, and Sara Mae Burns, 43, a wife with three children. They were the first officers to arrive at the scene of the early morning shooting and were shot as they rushed over to two people lying on the ground.
"This is the worst moment for any chief of police in any police agency to have to deliver this news," Fitch said at a news conference.
The shooting left two more people dead — both civilians, a man and woman — but police have not released their identities. The accused gunman, a 48-year-old Fredericton man, is in hospital. He has not been identified.
Costello, a detective known as Robb, worked on all manner of cases — from missing persons, robberies, street crimes, extortion, sex crimes — in Fredericton police's major crimes unit and while seconded to the RCMP's Internet child exploitation unit. He was a 20-year veteran of the force.
McLean said Costello would always leave for work with a smile.
"He loved being a police officer and he lived for being a police officer," McLean said. "He is the only police officer who I have ever known who could write someone a ticket and have the person thank them after."
Costello had two daughters from a previous relationship and McLean said he was also a role model for her two children.
"He is phenomenal as a father, he is very generous with his time and loved my children just as though they were his own," she said. "We were very close to one another, we spent all of our free time together."
In recent years, Costello drew the ire of local blogger and anti-police activist Charles LeBlanc. Costello and other fellow officers filed a criminal libel complaint against him over inflammatory internet postings and statements about the force. LeBlanc sued police saying Costello filed a request for information to LeBlanc's internet service provider as part of a previous libel investigation that mistakenly stated it was a child sexual exploitation investigation.
In an online video posted soon after the shooting, LeBlanc said he was woken by a police officer wondering if he might have been involved in the shooting.
"I'm glad I'm not in Fredericton," LeBlanc said. "Sympathies to everybody involved."
Const. Sara Burns grew up in Fredericton and joined the local police force in 2015, soon after graduating from the Atlantic Police Academy.
Burns went into policing after earning a bachelor of arts degree from Fredericton's St. Thomas University with a major in criminology in 2014, according to city records. She graduated Fredericton High School in 1994.
When she was sworn in as an officer, her husband, Steven Burns, founder of Fredericton IT company Bulletproof, praised her dedication; she returned to school to get her degree at the age of 35 while she helped raise their three sons. She then had to leave home for six months to attend the Atlantic Police Academy in Prince Edward Island.
Burns showed her love for policing and her city.
Posting on Facebook, she trumpeted her pride of being an officer during police week and shared her interest in helping the community through charity, youth and mental health supports and sport.
Burns told a newspaper in 2015 that she saw policing as a demanding career.
"(Policing) is something that I think challenges you physically, mentally and socially; you need to be aware of those components," she told the Journal Pioneer newspaper. "It's a really challenging field and to survive you need to keep all of those in check."
Earlier this year, Burns narrowly missed being hit by a knife thrown at her during a standoff with a barricaded man after three of her colleagues were hit with bear spray when entering an apartment.
"Our hearts are broken by the murder of our two brave police officers. In this time of shock and grief, let us all protect their families," Fredericton's mayor, Mike O'Brien, said on Twitter. "Two civilians also tragically lost their lives today. Our city sends its love and support to all. We grieve as one."
• Email: firstname.lastname@example.com | Twitter: AD_Humphreys

subset: commoncrawl


text:
Louder isn't better!
It seems obvious – but it's worth a reminder: the louder the noise and the longer the exposure, the greater the risk of damage to your ears. Even some sounds that don't seem loud or give you noticeable discomfort can damage your hearing. Loud sounds, of course, can cause damage much more quickly. Always remember that safety counts.
The decibel scale is matched to human hearing, so 0 dB is the very quietest sound that a human can hear without hearing loss. A "typical" spoken conversation is generally estimated to be 60 dB. Although this is not enough to hurt you, many every-day sounds are in the near-harmful range and can impact your hearing long term – so think safety first. A lawnmower, for example, averages in the 90 dB level, so it can cause damage. That's why it is important to wear protection whether you are mowing the lawn or around loud engines. Even a car travelling at 65 miles per hour or a vacuum cleaner can irritate your ears.
Most experts – including the National Institute for Occupation Safety and Health – agree that continued exposure to sounds over 85 dB risks damage to hearing. Therefore, workplace safety regulations usually require employers to provide protection for employees exposed to noisy environments. In the US, the Department of Labor regulates occupational noise exposure and has set a "permissible exposure limit" (PEL) of 90 dB for an 8 hour long day.
More dangerous – with immediate impact – are sounds in the 140 dB range. These include jet engines and gun shots. Even louder, is 180 dB of a rocket launch. These sounds can lead to permanent hearing damage. According to Purdue University, your eardrum can rupture if you are 25 meters or less from a jet as it is taking off.
Unfortunately, it is rarely immediately obvious when we damage our hearing – normally we notice it afterwards. However, with awareness, we can help protect our hearing. If you have to shout over background noise to make yourself heard, you may be in the danger zone where prolonged exposure could lead to damage.
If you notice ringing in your ears or experience pain, these are signs that your noise exposure is too high. This often appears after a noisy event such as a music concert. If you find it difficult to hear for several hours after exposure to loud sounds, or hear ringing in your ears or other unusual effects, then you probably have been around harmful levels.
Many people regularly use earphones or earbuds – on the way to school or work, while out running, or just while relaxing at home without considering the excess levels of noise exposure.
Earphones generally produce up to 100 dB, while some can produce even more. At this level, you risk damage to your hearing after a mere 15 minutes. Some smartphones have a feature that warns uses when the volume is at a dangerous level. Heed this warning and limit music at excessive volumes piped directly into your ears.
According to a recent study, just living in an urban area can increase your risk of hearing damage – by 64%. Traffic, construction, loud music, sirens and other environmental sounds of the city provide continuous exposure to noise can cause hearing damage.
At Smithtown Sayville Hearing Services we strive to educate and advise. If you want to learn if exposure to music, explosions or other noise has damaged your hearing, contact Smithtown Sayville Hearing Services for a complimentary hearing assessment*.
You will be redirected to our new website in 10 seconds. If not, click the button below.Visit HearingLife
Do you have concerns about your hearing? We have options for financing.Learn more
* Subject to credit approval.


text:
Houston Dynamo goalkeeper Pat Onstad became Canada's all-time leader in caps by a goalkeeper with his 57th appearance for the Canadian national team in Monday's friendly against Argentina.
Onstad, 42, started and played 90 minutes in Canada's 5-0 loss to the world power at Estadio Monumental. The appearance broke the record Onstad jointly held with Craig Forrest.
"I have been fortunate to enjoy a long career, and this Argentina match is right up there for me with some of the biggest I have ever experienced," said Onstad.
Onstad was just 20 years old when he made his national debut on February 18, 1988 in a 0-0 draw with Bermuda. He has since taken part in four CONCACAF Gold Cups (including a championship in 2000) and 18 FIFA World Cup qualifying matches. He holds the national record with 21 shutouts and is the oldest player in Canadian history at 42 years of age. Onstad is also Major League Soccer's all-time leader in goals against average.
Houston defender Andrew Hainault also started for Canada on Monday and played 90 minutes, his 17th appearance for Canada. Both players are expected to be available for the Dynamo's Saturday game against the Philadelphia Union at Robertson Stadium.


text:
We present a decision procedure for a logic that combines (i) word equations over string variables denoting words of arbitrary lengths, together with (ii) constraints on the length of words, and on (iii) the regular languages to which words belong. Decidability of this general logic is still open. Our procedure is sound for the general logic, and a decision procedure for a particularly rich fragment that restricts the form in which word equations are written. In contrast to many existing procedures, our method does not make assumptions about the maximum length of words. We have developed a prototypical implementation of our decision procedure, and integrated it into a CEGAR-based model checker for the analysis of programs encoded as Horn clauses. Our tool is able to automatically establish the correctness of several programs that are beyond the reach of existing methods.
We propose an automatic fence insertion and verification framework for concurrent programs running under relaxed memory. Unlike previous approaches to this problem, which allow only variables of finite domain, we target programs with (unbounded) integer variables. The problem is difficult because it has two different sources of infiniteness: unbounded store buffers and unbounded integer variables. Our framework consists of three main components: (1) a finite abstraction technique for the store buffers, (2) a finite abstraction technique for the integer variables, and (3) a counterexample guided abstraction refinement loop of the model obtained from the combination of the two abstraction techniques. We have implemented a prototype based on the framework and run it successfully on all standard benchmarks together with several challenging examples that are beyond the applicability of existing methods.
We introduce MEMORAX, a tool for the verification of control state reachability (i.e., safety properties) of concurrent programs manipulating finite range and integer variables and running on top of weak memory models. The verification task is non-trivial as it involves exploring state spaces of arbitrary or even infinite sizes. Even for programs that only manipulate finite range variables, the sizes of the store buffers could grow unboundedly, and hence the state spaces that need to be explored could be of infinite size. In addition, MEMORAX in- corporates an interpolation based CEGAR loop to make possible the verification of control state reachability for concurrent programs involving integer variables. The reachability procedure is used to automatically compute possible memory fence placements that guarantee the unreachability of bad control states under TSO. In fact, for programs only involving finite range variables and running on TSO, the fence insertion functionality is complete, i.e., it will find all minimal sets of memory fence placements (minimal in the sense that removing any fence would result in the reachability of the bad control states). This makes MEMORAX the first freely available, open source, push-button verification and fence insertion tool for programs running under TSO with integer variables.
We introduce TRAU, an SMT solver for an expressive constraint language, including word equations, length constraints, context-free membership queries, and transducer constraints. The satisfiability problem for such a class of constraints is in general undecidable. The key idea behind TRAU is a technique called flattening, which searches for satisfying assignments that follow simple patterns. TRAU implements a Counter-Example Guided Abstraction Refinement (CEGAR) framework which contains both an under- and an over-approximation module. The approximations are refined in an automatic manner by information flow between the two modules. The technique implemented by TRAU can handle a rich class of string constraints and has better performance than state-of-the-art string solvers.
We address the problem of parameterized verification of cache coherence protocols for hardware accelerated transactional memories. In this setting, transactional memories leverage on the versioning capabilities of the underlying cache coherence protocol. The length of the transactions, their number, and the number of manipulated variables (i.e., cache lines) are parameters of the verification problem. Caches in such systems are finite-state automata communicating via broadcasts and shared variables. We augment our system with filters that restrict the set of possible executable traces according to existing conflict resolution policies. We show that the verification of coherence for parameterized cache protocols with filters can be reduced to systems with only a finite number of cache lines. For verification, we show how to account for the effect of the adopted filters in a symbolic backward reachability algorithm based on the framework of constrained monotonic abstraction. We have implemented our method and used it to verify transactional memory coherence protocols with respect to different conflict resolution policies.
We consider the verification of safety (strict se- rializability and abort consistency) and liveness (obstruction and livelock freedom) for the hybrid transactional memory framework FLEXTM. This framework allows for flexible imple- mentations of transactional memories based on an adaptation of the MESI coherence protocol. FLEXTM allows for both eager and lazy conflict resolution strategies. Like in the case of Software Transactional Memories, the verification problem is not trivial as the number of concurrent transactions, their size, and the number of accessed shared variables cannot be a priori bounded. This complexity is exacerbated by aspects that are specific to hardware and hybrid transactional memories. Our work takes into account intricate behaviours such as cache line based conflict detection, false sharing, invisible reads or non-transactional instructions. We carry out the first automatic verification of a hybrid transactional memory and establish, by adopting a small model approach, challenging properties such as strict serializability, abort consistency, and obstruction freedom for both an eager and a lazy conflict resolution strategies. We also detect an example that refutes livelock freedom. To achieve this, our prototype tool makes use the latest antichain based techniques to handle systems with tens of thousands of states.
We present a technique for automatically verifying safety properties of concurrent programs, in particular programs which rely on subtle dependencies of local states of different threads, such as lock-free implementations of stacks and queues in an environment without garbage collection. Our technique addresses the joint challenges of infinite-state specifications, an unbounded number of threads, and an unbounded heap managed by explicit memory allocation. Our technique builds on the automata-theoretic approach to model checking, in which a specification is given by an automaton that observes the execution of a program and accepts executions that violate the intended specification.We extend this approach by allowing specifications to be given by a class of infinite-state automata. We show how such automata can be used to specify queues, stacks, and other data structures, by extending a data-independence argument. For verification, we develop a shape analysis, which tracks correlations between pairs of threads, and a novel abstraction to make the analysis practical. We have implemented our method and used it to verify programs, some of which have not been verified by any other automatic method before.
Requirements Engineering (RE) in Agile Software Development (ASD) is a challenge thatmany face and several techniques exist when doing so. One such technique is prototyping, when a model of a product is used to gather important information in software develop-ment. To describe how much a prototype resembles the product the notion of fidelity is used. The aim of this study is to contribute to research regarding prototyping in ASD,and to examine the effect of a prototype's fidelity when using prototypes in discussionsduring RE. A case study is performed at the company Exsitec where staff are interviewedregarding prototyping in software development. Thereafter, two prototypes of low andhigh fidelity are developed and used in interviews as a basis for discussion. Based on thisstudy, the use of prototypes in software projects can help customers trust the process,improve communication with customers, and facilitate when trying to reach consensusamong different stakeholders. Furthermore, depending on how they are used, prototypescan contribute to understanding the big picture of the requirements and can also serve asdocumentation. The study also shows some, albeit subtle, differences in the informationcollected using prototypes with low and high fidelity. The use of a high fidelity prototypeseems to generate more requirements, but makes interviewees less likely to come up withlarger, more comprehensive requirement changes.
Creating native mobile application on multiple platforms generate a lot of duplicate code. This thesis has evaluated if the code quality attribute modifiability improves when migrating to React Native. One Android and one iOS codebase existed for an application and a third codebase was developed with React Native. The measurements of the codebases were based on the SQMMA-model. The metrics for the model were collected with static analyzers created specifically for this project. The results created consists of graphs that show the modifiability for some specific components over time and graphs that show the stability of the platforms. These graphs show that when measuring code metrics on applications over time it is better to do this on a large codebase that has been developed for some time. When calculating a modifiability value the sum of the metrics and the average value of the metrics between files should be used and it is shown that the React Native platform seems to be more stable than native.
The existing approaches to design efficient safety critical control applications is constrained by limited in-vehicle sensing and computational capabilities. In the context of automated driving, we argue that there is a need to leverage resources "out-of-the-vehicle" to meet the sensing and powerful processing requirements of sophisticated algorithms (e.g., deep neural networks). To realize the need, a suitable computation offloading technique that meets the vehicle safety and stability requirements, even in the presence of unreliable communication network, has to be identified. In this work, we propose an adaptive offloading technique for control computations into the cloud. The proposed approach considers both current network conditions and control application requirements to determine the feasibility of leveraging remote computation and storage resources. As a case study, we describe a cloud-based path following controller application that leverages crowdsensed data for path planning.
High temperature and process variation areundesirable effects for modern systems-on-chip. The hightemperature is a prominent issue during test and should be takencare of during the test process. Modern SoCs, affected by largeprocess variation, experience rapid and large temperaturedeviations and, therefore, a traditional static test schedule which isunaware of these deviations will be suboptimal in terms of speedand/or thermal-safety. This paper presents an adaptive testscheduling method which addresses the temperature deviationsand acts accordingly in order to improve the test speed andthermal-safety. The proposed method is divided into acomputationally intense offline-phase, and a very simple online-phase.In the offline-phase a schedule tree is constructed, and inthe online-phase the appropriate path in the schedule tree istraversed, step by step and based on temperature sensor readings.Experiments have demonstrated the efficiency of the proposedmethod.
Burn-in is usually carried out with high temperature and elevated voltage. Since some of the early-life failures depend not only on high temperature but also on temperature gradients, simply raising up the temperature of an IC is not sufficient to detect them. This is especially true for 3D stacked ICs, since they have usually very large temperature gradients. The efficient detection of these early-life failures requires that specific temperature gradients are enforced as a part of the burn-in process. This paper presents an efficient method to do so by applying high power stimuli to the cores of the IC under burn-in through the test access mechanism. Therefore, no external heating equipment is required. The scheduling of the heating and cooling intervals to achieve the required temperature gradients is based on thermal simulations and is guided by functions derived from a set of thermal equations. Experimental results demonstrate the efficiency of the proposed method.
In a modern 3D IC, electrical connections between vertically stacked dies are made using through silicon vias. Through silicon vias are subject to undesirable early-life effects such as protrusion as well as void formation and growth. These effects result in opens, resistive opens, and stress induced carrier mobility reduction, and consequently circuit failures. Operating the ICs under extreme temperature cycling can effectively accelerate such early-life failures and make them detectable at the manufacturing test process. An integrated temperature-cycling acceleration and test technique is introduced in this paper that integrates a temperature-cycling acceleration procedure with pre-, mid-, and post-bond tests for 3D ICs. Moreover, it reduces the need for costly temperature chamber based temperature-cycling acceleration procedures. All these result in a reduction in the overall test costs. The proposed method is a schedule-based solution that creates the required temperature cycling effect along with performing the tests. Experimental results demonstrate its efficiency.
Different defects may manifest themselves at different temperatures. Therefore, the tests that target such temperature-dependent defects must be applied at different temperatures appropriate for detecting them. Such multi-temperature testing scheme applies tests at different required temperatures. It is known that a test's power dissipation depends on the previously applied test. Therefore, the same set of tests when organized differently dissipates different amounts of power. The technique proposed in this paper organizes the tests efficiently so that the resulted power levels lead to the required temperatures. Consequently a rapid multi-temperature testing is achieved. Experimental studies demonstrate the efficiency of the proposed technique.
High working temperature and process variation are undesirable effects for modern systems-on-chip. The high temperature should be taken care of during the test. On the other hand, large process variations induce rapid and large temperature deviations causing the traditional static test schedules to be suboptimal in terms of speed and/or thermal-safety. A remedy to this problem is an adaptive test schedule which addresses the temperature deviations by reacting to them. Our adaptive method is divided into a computationally intense offline-phase, and a very simple online-phase. In this paper, heuristics are proposed for the offline phase in which the optimized schedule tree is found. In the online-phase, based on the temperature sensor readings the appropriate path in the schedule tree is traversed. Experiments are made to tune the proposed heuristics and to demonstrate their efficiency.
High temperature and process variation are undesirable phenomena affecting modern Systems-on-Chip (SoC). High temperature is a well-known issue, in particular during test, and should be taken care of in the test process. Modern SoCs are affected by large process variation and therefore experience large and time-variant temperature deviations. A traditional test schedule which ignores these deviations will be suboptimal in terms of speed or thermal-safety. This paper presents an adaptive test scheduling method which acts in response to the temperature deviations in order to improve the test speed and thermal safety. The method consists of an offline phase and an online phase. In the offline phase a schedule tree is constructed and in the online phase the appropriate path in the schedule tree is traversed based on temperature sensor readings. The proposed technique is designed to keep the online phase very simple by shifting the complexity into the offline phase. In order to efficiently produce high-quality schedules, an optimization heuristic which utilizes a dedicated thermal simulation is developed. Experiments are performed on a number of SoCs including the ITC'02 benchmarks and the experimental results demonstrate that the proposed technique significantly improves the cost of the test in comparison with the best existing test scheduling method.
Chips manufactured with deep sub micron technologies are prone to large process variation and temperature-dependent defects. In order to provide high test efficiency, the tests for temperature-dependent defects should be applied at appropriate temperature ranges. Existing static scheduling techniques achieve these specified temperatures by scheduling the tests, specially developed heating sequences, and cooling intervals together. Because of the temperature uncertainty induced by process variation, a static test schedule is not capable of applying the tests at intended temperatures in an efficient manner. As a result the test cost will be very high. In this paper, an adaptive test scheduling method is introduced that utilizes on-chip temperature sensors in order to adapt the test schedule to the actual temperatures. The proposed method generates a low cost schedule tree based on the variation statistics and thermal simulations in the design phase. During the test, a chip selects an appropriate schedule dynamically based on temperature sensor readings. A 23% decrease in the likelihood that tests are not applied at the intended temperatures is observed in the experimental studies in addition to 20% reduction in test application time.
3D Stacked IC fabrication, using Through-Silicon-Vias, is a promising technology for future integrated circuits. However, large temperature gradients may exacerbate early-life-failures to the extent that the commercialization of 3D Stacked ICs is challenged. The effective detection of these early-life-failures requires that burn-in is performed when the IC's temperatures comply with the thermal maps that properly specify the temperature gradients. In this paper, two methods that efficiently generate and maintain the specified thermal maps are proposed. The thermal maps are achieved by applying heating and cooling intervals to the chips under test through test access mechanisms. Therefore, no external heating system is required. The scheduling of the heating and cooling intervals is based on thermal simulations. The schedule generation is guided by functions that are derived from the temperature equations. Experimental results demonstrate the efficiency of the proposed method.
Defects that are dependent on temperature-gradients (e.g., delay-faults) introduce a challenge for achieving an effective test process, in particular for 3D ICs. Testing for such defects must be performed when the proper temperature gradients are enforced on the IC, otherwise these defects may escape the test. In this paper, a technique that efficiently heats up the IC during test so that it complies with the specified temperature gradients is proposed. The specified temperature gradients are achieved by applying heating sequences to the cores of the IC under test trough test access mechanism; thus no external heating mechanism is required. The scheduling of the test and heating sequences is based on thermal simulations. The schedule generation is guided by functions derived from the IC's temperature equation. Experimental results demonstrate that the proposed technique offers considerable test time savings.
Large temperature gradients exacerbate various types of defects including early-life failures and delay faults. Efficient detection of these defects requires that burn-in and test for delay faults, respectively, are performed when temperature gradients with proper magnitudes are enforced on an Integrated Circuit (IC). This issue is much more important for 3-D stacked ICs (3-D SICs) compared with 2-D ICs because of the larger temperature gradients in 3-D SICs. In this paper, two methods to efficiently enforce the specified temperature gradients on the IC, for burn-in and delay-fault test, are proposed. The specified temperature gradients are enforced by applying high-power stimuli to the cores of the IC under test through the test access mechanism. Therefore, no external heating mechanism is required. The tests, high power stimuli, and cooling intervals are scheduled together based on temperature simulations so that the desired temperature gradients are rapidly enforced. The schedule generation is guided by functions derived from a set of thermal equations. The experimental results demonstrate the efficiency of the proposed methods.
Automated planning is known to be computationally hard in the general case. Propositional planning is PSPACE-complete and first-order planning is undecidable. One method for analyzing the computational complexity of planning is to study restricted subsets of planning instances, with the aim of differentiating instances with varying complexity. We use this methodology for studying the computational complexity of planning. Finding new tractable (i.e. polynomial-time solvable) problems has been a particularly important goal for researchers in the area. The reason behind this is not only to differentiate between easy and hard planning instances, but also to use polynomial-time solvable instances in order to construct better heuristic functions and improve planners. We identify a new class of tractable cost-optimal planning instances by restricting the causal graph. We study the computational complexity of oversubscription planning (such as the net-benefit problem) under various restrictions and reveal strong connections with classical planning. Inspired by this, we present a method for compiling oversubscription planning problems into the ordinary plan existence problem. We further study the parameterized complexity of cost-optimal and net-benefit planning under the same restrictions and show that the choice of numeric domain for the action costs has a great impact on the parameterized complexity. We finally consider the parameterized complexity of certain problems related to partial-order planning. In some applications, less restricted plans than total-order plans are needed. Therefore, a partial-order plan is being used instead. When dealing with partial-order plans, one important question is how to achieve optimal partial order plans, i.e. having the highest degree of freedom according to some notion of flexibility. We study several optimization problems for partial-order plans, such as finding a minimum deordering or reordering, and finding the minimum parallel execution length.
Aghighi and Bäckström have previously studied cost-optimal planning (COP) and net-benefit planning (NBP) for three action cost domains: the positive integers (Z_+), the non-negative integers (Z_0) and the positive rationals (Q_+). These were indistinguishable under standard complexity analysis for both problems, but separated for COP using parameterised complexity analysis. With the plan cost, k, as parameter, COP was W[2]-complete for Z_+, but para-NP-hard for both Z_0 and Q_+, i.e. presumably much harder. NBP was para-NP-hard for all three domains, thus remaining unseparable. We continue by considering combinations with several additional parameters and also the non-negative rationals (Q_0). Examples of new parameters are the plan length, l, and the largest denominator of the action costs, d. Our findings include: (1) COP remains W[2]-hard for all domains, even if combining all parameters; (2) COP for Z_0 is in W[2] for the combined parameter {k,l}; (3) COP for Q_+ is in W[2] for {k,d} and (4) COP for Q_0 is in W[2] for {k,d,l}. For NBP we consider further additional parameters, where the most crucial one for reducing complexity is the sum of variable utilities. Our results help to understand the previous results, eg. the separation between Z_+ and Q_+ for COP, and to refine the previous connections with empirical findings.
Cost-optimal planning (COP) uses action costs and asks for a minimum-cost plan. It is sometimes assumed that there is no harm in using actions with zero cost or rational cost. Classical complexity analysis does not contradict this assumption; planning is PSPACE-complete regardless of whether action costs are positive or non-negative, integer or rational. We thus apply parameterised complexity analysis to shed more light on this issue. Our main results are the following. COP is W[2]-complete for positive integer costs, i.e. it is no harder than finding a minimum-length plan, but it is para-NPhard if the costs are non-negative integers or positive rationals. This is a very strong indication that the latter cases are substantially harder. Net-benefit planning (NBP) additionally assigns goal utilities and asks for a plan with maximum difference between its utility and its cost. NBP is para-NP-hard even when action costs and utilities are positive integers, suggesting that it is harder than COP. In addition, we also analyse a large number of subclasses, using both the PUBS restrictions and restricting the number of preconditions and effects.
Bäckström has previously studied a number of optimization problems for partial-order plans, like finding a minimum deordering (MCD) or reordering (MCR), and finding the minimum parallel execution length (PPL), which are all NP-complete. We revisit these problems, but applying parameterized complexity analysis rather than standard complexity analysis. We consider various parameters, including both the original and desired size of the plan order, as well as its width and height. Our findings include that MCD and MCR are W[2]-hard and in W[P] when parameterized with the desired order size, and MCD is fixed-parameter tractable (fpt) when parameterized with the original order size. Problem PPL is fpt if parameterized with the size of the non-concurrency relation, but para-NP-hard in most other cases. We also consider this problem when the number (k) of agents, or processors, is restricted, finding that this number is a crucial parameter; this problem is fixed-parameter tractable with the order size, the parallel execution length and k as parameter, but para-NP-hard without k as parameter.
Cost-optimal planning has become a very well-studied topic within planning. Needless to say, cost-optimal planning has proven to be computationally hard both theoretically and in practice. Since cost-optimal planning is an optimisation problem, it is natural to analyse it from an approximation point of view. Even though such studies may be valuable in themselves, additional motivation is provided by the fact that there is a very close link between approximability and the performance of heuristics used in heuristic search. The aim of this paper is to analyse approximability (and indirectly the performance of heuristics) with respect to lower time bounds. That is, we are not content by merely classifying problems into complexity classes - we also study their time complexity. This is achieved by replacing standard complexity-theoretic assumptions (such as P not equal NP) with the exponential time hypothesis (ETH). This enables us to analyse, for instance, the performance of the h(+) heuristic and obtain general trade-off results that correlate approximability bounds with bounds on time complexity.
The use of computational complexity in planning, and in AI in general, has always been a disputed topic. A major problem with ordinary worst-case analyses is that they do not provide any quantitative information: they do not tell us much about the running time of concrete algorithms, nor do they tell us much about the running time of optimal algorithms. We address problems like this by presenting results based on the exponential time hypothesis (ETH), which is a widely accepted hypothesis concerning the time complexity of 3-SAT. By using this approach, we provide, for instance, almost matching upper and lower bounds onthe time complexity of propositional planning.
Many real-world planning problems are oversubscription problems where all goals are not simultaneously achievable and the planner needs to find a feasible subset. We present complexity results for the so-called partial satisfaction and net benefit problems under various restrictions; this extends previous work by van den Briel et al. Our results reveal strong connections between these problems and with classical planning. We also present a method for efficiently compiling oversubscription problems into the ordinary plan existence problem; this can be viewed as a continuation of earlier work by Keyder and Geffner.
Causal graphs are widely used to analyze the complexity of planning problems. Many tractable classes have been identified with their aid and state-of-the-art heuristics have been derived by exploiting such classes. In particular, Katz and Keyder have studied causal graphs that are hourglasses (which is a generalization of forks and inverted-forks) and shown that the corresponding cost-optimal planning problem is tractable under certain restrictions. We continue this work by studying polytrees (which is a generalization of hourglasses) under similar restrictions. We prove tractability of cost-optimal planning by providing an algorithm based on a novel notion of variable isomorphism. Our algorithm also sheds light on the k-consistency procedure for identifying unsolvable planning instances. We speculate that this may, at least partially, explain why merge-and-shrink heuristics have been successful for recognizing unsolvable instances.
When communicating with spacecrafts, the international standard is to use the protocols defined by CCSDS. In this study, the Space Packet Protocol from CCSDS is converted to the Digital Recording Standard used in aviation. The goal of the study is to find out in what way such a conversion can be made, as well as analyzing the efficiency of different packing methods for the Digital Recording Standard. An application is developed in order to perform the conversion, and the performance of said application is profiled using different packet sizes. In the end the results are evaluated and an optimal packet size is found in terms of runtime and memory usage. In the end we conclude that a packet size of 216 bytes is best when prioritizing speed, and a packet size of 219 bytes is best when prioritizing memory.
Mobile applications should work regardless of which type of wireless interface is used, and should be able to conceal unstable connections from the user to improve user experience. Therefore, network testing is important when developing mobile applications, but it is a challenge to reproduce network conditions when using real cellular networks since the test engineer has no control over the quality of the cellular network. Existing software tools can restrict bandwidth and add latency to the connection, but these tools do not accurately emulate cellular networks.
This thesis proposes a system where it is possible to shape the network traffic for connected devices to mimic the network patterns of a real cellular connection when running on a WiFi connection. The design presented in this thesis is intended for testing mobile applications under diverse 3G connection parameters, such as latency, bandwidth and other characteristics.
This thesis was conducted at Spotify, a company that provides a music streaming service which is a frequent user of network data traffic. The 3G emulator was evaluated using the Spotify Android application by measuring the correlation between packet traces from a real 3G connection and the 3G emulator. This correlation was compared to the correlation between packet traces from a real 3G connection and the current network emulator at Spotify. The evaluation shows that the proposed 3G emulator outperforms the current network emulator when performing tests on the Spotify application for Android. By using this emulator, we expect the network testing to become more effective as any 3G condition can be tested with repeatable results.
Ubiquitous connectivity and massive use of mobile applications are currently hampered by fast battery drain of mobile devices. The communication energy of a mobile device is highly inuenced by the cellular operator conguration and the communication data pattern. Although testing the functionality and eciency of an application under diverse and realistic network settings is desirable, it is currently limited at the application developer test environment. It is generally hard to mimic di erent operator (infrastructure) settings that impact battery drain. In this paper we propose a system that creates a realistic cellular network testing environment for mobile applications on top of a WiFi network. A mobile device connects via WiFi to an emulator which shapes the uplink and downlink WiFi trac using real cellular operator conguration parameters. The system provides higher test repeatability compared to live networks and can be congured to emulate diverse cellular network parameters. These parameters, which determine the energy consumption, can be changed modularly and eciently. The evaluation of the resulting trac of the emulator compared to real cellular packet races from a streaming application shows a high correlation (0.97-0.98). The work has resulted in integration of the emulator within Spotify's test environment.
Being able to run applications written in a single language on multiple platforms is a strong incentive for migrating applications to the web. This along with the possibility to avoid the sometimes problematic procedure of installing software, makes the case even stronger. This thesis investigates how to migrate a workflow graph editing system into a web technology in order to publish it on the web. We will evaluate a number of different technologies such as WebGL, HTML5 canvas and SVG. SVG is deemed as the preferred technology due to its advantages when it comes to interaction. As it can leverage JavaScripts event system we get a potent way of handling events without writing a single line of code. When combining this with the framework D3JS we achieve a great tool for writing workflow management systems.
In this work, we evaluate the effectiveness of OpenCL for programming multicore CPUs in a comparative case study with OpenMP and Intel TBB for five benchmark applications: matrix multiply, LU decomposition, 2D image convolution, Pi value approximation and image histogram generation.
Shared memory multicore processor technology is pervasive in mainstream computing. This new architecture challenges programmers to write code that scales over these many cores to exploit the full computational power of these machines. OpenMP and Intel Threading Building Blocks (TBB) are two of the popular frameworks used to program these architectures. Recently, OpenCL has been defined as a standard by Khronos group which focuses on programming a possibly heterogeneous set of processors with many cores such as CPU cores, GPUs, DSP processors. In this work, we evaluate the effectiveness of OpenCL for programming multicore CPUs in a comparative case study with OpenMP and Intel TBB for five benchmark applications: matrix multiply, LU decomposition,2D image convolution, Pi value approximation and image histogram generation. The evaluation includes the effect of compiler optimizations for different frameworks, OpenCL performance on different vendors' platformsand the performance gap between CPU-specific and GPU-specific OpenCL algorithms for execution on a modern GPU. Furthermore, a brief usability evaluation of the three frameworks is also presented.
Trends show that cyber attacks targeting critical infrastructures are increasing, but security research for protecting such systems are challenging. There is a gap between the somewhat simplified models researchers at universities can sustain contra the complex systems at infrastructure owners that seldom can be used for direct research. There is also a lack of common datasets for research benchmarking. This paper presents a national experimental testbed for security research within supervisory control and data acquisition systems (SCADA), accessible for both research training and experiments. The virtualized testbed has been designed and implemented with both vendor experts and security researchers to balance the goals of realism with specific research needs. It includes a real SCADA product for energy management, a number of network zones, substation nodes, and a simulated power system. This environment enables creation of scenarios similar to real world utility scenarios, attack generation, development of defence mechanisms, and perhaps just as important: generating open datasets for comparative research evaluation.
The popularity of mobile games has increased drastically during the recent years andmany people use them as their main source of entertainment. Mobile gamescommunicate with other devices over the network which consumes a lot of energy,especially when connected to cellular networks (e.g., 3G). This high energy expensecan feel unjustified to the player since always-on network connectivity is not requiredin order to play most games.Furthermore, the number of malware-infected applications in offical applicationstores has increased significantly in the recent years. These malware-infectedapplications can gain unrestricted access and control of users phones which can be athreat to security. Information about the behaviour characteristics of games can beused to develop or improve systems for detecting malware applications.In this thesis, 20 popular Android games are analysed with a focus on the datacommunication, CPU utilization and system call behaviour. The main subject of thedata communication study is the 3G communication energy consumed by games. Thesystem call study aims at quantifying the number and type of calls used by games.This may be useful in a further study of harmful behaviour by apps.The profiling results presented in this report show that the communication energyvaries drastically among games. Games with a very similar gameplay can consumevery different amounts of energy which indicates that there is room for improvementsin many of the games. Ad-free games consume significantly less energy than gamesthat use in-app advertisements. The results show that improving the advertisementfetching policy could reduce the energy consumption of these games. The majority ofthe games can be played without network connectivity and therefore thecommunication energy consumed could be completely avoided. The thesis alsoshows that games use a wide variety of system calls and that many of the system callsare common among the games.
Although a significant proportion of the mobile apps are games there has been little attention paid to their specific characteristics with respect to communication energy. In this paper we select 20 mobile games among the top 100 free Android games, and study their data patterns and communication energy use over a total of 25 hours of playing. The analysis of the energy for communication over 3G networks indicates that there is a wide variation among the games, the largest footprint being 8 times higher than the lowest one. The results also indicates both app-specific and category-specific relations between data pattern and energy use, as well as variations in CPU utilisation.
I databasapplikationer är det viktigt att kunna minska belastningen på en databas i syfte att minska responstiden. Detta kan exempelvis åstadkommas med hjälp av olika metoder för temporär lagring av data, något som studerats i detta arbete. De metoder som utvärderats och jämförts i detta arbete är Redis och memcached. Utvärderingen jämförde Redis och memcached med avseende på minnesanvändning, CPU-användning och tidsåtgång för hämtning av data i respektive cache. Dessa egenskaper beräknades med hjälp av verktygen SYSSTAT och valgrind. Det visade sig i slutändan att den interna fragmenteringen i memcached är dess största nackdel, medan Redis är något långsammare än memcached när det gäller att hämta stora mängder data. Utifrån de resultat som anskaffats var det tänkt att använda den metod som är mest lämpad för SysPartners ändamål, vilket ansågs vara Redis.
REPLICA is a family of novel scalable chip multiprocessors with configurable emulated shared memory architecture, whose computation model is based on the PRAM (Parallel Random Access Machine) model.
The purpose of this thesis is to, by benchmarking different types of computation problems on REPLICA, similar parallel architectures (SB-PRAM and XMT) and more diverse ones (Xeon X5660 and Tesla M2050), evaluate how REPLICA is positioned among other existing architectures, both in performance and programming effort. But it should also examine if REPLICA is more suited for any special kinds of computational problems.
By using some of the well known Berkeley dwarfs, and input from unbiased sources, such as The University of Florida Sparse Matrix Collection and Rodinia benchmark suite, we have made sure that the benchmarks measure relevant computation problems.
We show that today's parallel architectures have some performance issues for applications with irregular memory access patterns, which the REPLICA architecture can solve. For example, REPLICA only need to be clocked with a few MHz to match both Xeon X5660 and Tesla M2050 for the irregular memory access benchmark breadth first search. By comparing the efficiency of REPLICA to a CPU (Xeon X5660), we show that it is easier to program REPLICA efficiently than today's multiprocessors.
In the last decade modern information technology systems have been introduced to healthcare in order to improve it. The aim of this study is to present the impact of such information system's adoption on patient safety and efficiency within healthcare.
Interviews, observations along with literature study were conducted in order to study the impact of the adoption on patient safety and efficiency at hospital's wards where a new information system is implemented.
The conclusion of this study is that such information technology systems can improve patient safety. However it is believed that the information technology system can improve efficiency in some aspects such as the communication among medical care personnel while other aspects within efficiency can be achieved if some improvements are made. Moreover the ability to access Electronic Healthcare Records is considered to be important to improve the medical care, which can increase patient safety.
A major challenge in modelling and simulation is the need to combine expertise in both software technologies and a given scientific domain. When High-Performance Computing (HPC) is required to solve a scientific problem, software development becomes a problematic issue. Considering the complexity of the software for HPC, it is useful to identify programming languages that can be used to alleviate this issue. Because the existing literature on the topic of HPC is very dispersed, we performed a Systematic Mapping Study (SMS) in the context of the European COST Action cHiPSet. This literature study maps characteristics of various programming languages for data-intensive HPC applications, including category, typical user profiles, effectiveness, and type of articles. We organised the SMS in two phases. In the first phase, relevant articles are identified employing an automated keyword-based search in eight digital libraries. This lead to an initial sample of 420 papers, which was then narrowed down in a second phase by human inspection of article abstracts, titles and keywords to 152 relevant articles published in the period 2006-2018. The analysis of these articles enabled us to identify 26 programming languages referred to in 33 of relevant articles. We compared the outcome of the mapping study with results of our questionnaire-based survey that involved 57 HPC experts. The mapping study and the survey revealed that the desired features of programming languages for data-intensive HPC applications are portability, performance and usability. Furthermore, we observed that the majority of the programming languages used in the context of data-intensive HPC applications are text-based general-purpose programming languages. Typically these have a steep learning curve, which makes them difficult to adopt. We believe that the outcome of this study will inspire future research and development in programming languages for data-intensive HPC applications. (C) 2019 Elsevier B.V. All rights reserved.
Today, many embedded or cyber-physical systems, e.g., in the automotive domain, comprise several control applications, sharing the same platform. It is well known that such resource sharing leads to complex temporal behaviors that degrades the quality of control, and more importantly, may even jeopardize stability in the worst case, if not properly taken into account.
In this thesis, we consider embedded control or cyber-physical systems, where several control applications share the same processing unit. The focus is on the control-scheduling co-design problem, where the controller and scheduling parameters are jointly optimized. The fundamental difference between control applications and traditional embedded applications motivates the need for novel methodologies for the design and optimization of embedded control systems. This thesis is one more step towards correct design and optimization of embedded control systems.
Offline and online methodologies for embedded control systems are covered in this thesis. The importance of considering both the expected control performance and stability is discussed and a control-scheduling co-design methodology is proposed to optimize control performance while guaranteeing stability. Orthogonal to this, bandwidth-efficient stabilizing control servers are proposed, which support compositionality, isolation, and resource-efficiency in design and co-design. Finally, we extend the scope of the proposed approach to non-periodic control schemes and address the challenges in sharing the platform with self-triggered controllers. In addition to offline methodologies, a novel online scheduling policy to stabilize control applications is proposed.
Today, many control applications in embedded and cyber-physical systems are implemented on shared platforms, alongside other hard real-time or safety-critical applications. Having the resource shared among several applications, to provide hard guarantees, it is required to identify the amount of resource needed for each application. This is rather straightforward when the platform is shared among periodic control and periodic real-time applications. In the case of event-triggered and self-triggered controllers, however, the execution patterns and, in turn, the resource usage are not clear. Therefore, a major implementation challenge, when the platform is shared with self-triggered controllers, is to provide hard and efficient stability and schedulability guarantees for other applications. In this paper, we identify certain execution patterns for self-triggered controllers, using which we are able to provide hard and efficient stability guarantees for periodic control applications.
Today, a considerable portion of embedded systems, e.g., automotive and avionic, comprise several control applications. Guaranteeing the stability of these control applications in embedded systems, or cyber-physical systems, is perhaps the most fundamental requirement while implementing such applications. This is different from the classical hard real-time systems where often the acceptance criterion is meeting the deadline. In other words, in the case of control applications, guaranteeing stability is considered to be a main design goal, which is linked to the amount of delay and jitter a control application can tolerate before instability. This advocates the need for new design and analysis techniques for embedded real-time systems running control applications. In this paper, the analysis and design of such systems considering a server-based resource reservation mechanism are addressed. The benefits of employing servers are manifold: providing a compositional and scalable framework, protection against other tasks misbehaviors, and systematic bandwidth assignment and co-design. We propose a methodology for designing bandwidth-optimal servers to stabilize control tasks. The pessimism involved in the proposed methodology is both discussed theoretically and evaluated experimentally.
Many cyber-physical systems comprise several control applications implemented on a shared platform, for which stability is a fundamental requirement. This is as opposed to the classical hard real-time systems where often the criterion is meeting the deadline. However, the stability of control applications depends on not only the delay experienced, but also the jitter. Therefore, the notion of deadline is considered to be artificial for control applications that promotes the need for new techniques for designing cyber-physical systems. The approach in this paper is built on a server-based resource reservation mechanism, which provides compositionality, isolation, and the opportunity of systematic controller--server co-design. We address the controller--server co-design of such systems to obtain design solutions with the minimal bandwidth to guarantee stability.
Guaranteeing stability of control applications in embedded systems, or cyber-physical systems, is perhaps the alpha and omega of implementing such applications. However, as opposed to the classical real-time systems where often the acceptance criterion is meeting the deadline, control applications do not primarily enforce hard deadlines. In the case of control applications, stability is considered to be the main design criterion and can be expressed in terms of the amount of delay and jitter a control application can tolerate before instability. Therefore, new design and analysis techniques are required for embedded control systems. In this paper, the analysis and design of such systems considering server-based resource reservation mechanism are addressed. The benefits of employing servers are manifold: (1) providing a compositional framework, (2) protection against other tasks misbehaviors, and (3) systematic bandwidth assignment. We propose a methodology for designing bandwidth-efficient servers to stabilize control tasks.
Control applications are considered to be among the core applications in cyber-physical and embedded realtime systems, for which jitter is typically an important factor. This paper investigates whether it is possible to guarantee certain amount of jitter for a given set of applications on a shared platform. The effect of jitter on the stability of control applications and its relation with the latency will be discussed. The importance arises from the fact that it is considerably easier to manage the constant part of the delay (known as latency), while the process of coping with the varying part of the delay (known as jitter) is more involved. The proposed solution guarantees certain jitter limits, and at the same time does not lead to overly pessimistic latency values. The results are later used in a design optimization problem to minimize the resource utilized.
Today, security can no longer be treated as a secondary issue in embedded and cyber-physical systems. Therefore, one of the main challenges in these domains is the design of secure embedded systems under stringent resource constraints and real-time requirements. However, there exists an inherent trade-off between the security protection provided and the amount of resources allocated for this purpose. That is, the more the amount of resources used for security, the higher the security, but the fewer the number of applications which can be run on the platform and meet their timing requirements. This trade-off is of high importance since embedded systems are often highly resource constrained. In this paper, we propose an efficient solution to maximize confidentiality, while also guaranteeing the timing requirements of real-time applications on shared platforms.
Many cyber-physical systems comprise several control applications sharing communication and computation resources. The design of such systems requires special attention due to the complex timing behavior that can lead to poor control quality or even instability. The two main requirements of control applications are: (1) robustness and, in particular, stability and (2) high control quality. Although it is essential to guarantee stability and provide a certain degree of robustness even in the worst-case scenario, a design procedure which merely takes the worst-case scenario into consideration can lead to a poor expected (average-case) control quality, since the design is solely tuned to a scenario that occurs very rarely. On the other hand, considering only the expected quality of control does not necessarily provide robustness and stability in the worst-case. Therefore, both the robustness and the expected control quality should be taken into account in the design process. This paper presents an efficient and integrated approach for designing high-quality cyber-physical systems with robustness guarantees.
Many embedded systems comprise several controllers sharing available resources. It is well known that such resource sharing leads to complex timing behavior that can jeopardize stability of control applications, if it is not properly taken into account in the design process, e.g., mapping and scheduling. As opposed to hard real-time systems where meeting the deadline is a critical requirement, control applications do not enforce hard deadlines. Therefore, the traditional real-time analysis approaches are not readily applicable to control applications. Rather, in the context of control applications, stability is often the main requirement to be guaranteed, and can be expressed as the amount of delay and jitter a control application can tolerate. The nominal delay and response-time jitter can be regarded as the two main factors which relate the real-time aspects of a system to control performance and stability. Therefore, it is important to analyze the impact of variations in scheduling parameters, i.e., period and priority, on the nominal delay and response-time jitter and, ultimately, on stability. Based on such an analysis, we address, in this paper, priority assignment and sensitivity analysis problems for control applications considering stability as the main requirement.


text:
Did the Buddha Believe in God?
I wanted to share what arose for me out of a friendly discussion with a Buddhist acquaintance over whether the Buddha had a conception of God. Some people believe that he had none.
I personally don't share that view and thought it would be enjoyable to review some of the statements in which he appears to acknowledge a belief in God – well, not a belief really, as we think of it, because Buddha would have experienced God directly and profoundly and passed beyond belief.
Far from being a non-believer in God, the Buddha acknowledged "one common essence" (1) which he, with his deeply-penetrating spiritual insight, was able to see and know. As far as I can see, this "one common essence" was God, as he implies in this further statement:
"If we examine the origin of anything in all the universe, we find that it is but a manifestation of some primal essence. Even the tiny leaves of herbs, knots of threads, everything, if we examine them carefully we find that there is some essence in its originality. Even open space is not nothingness. How can it be then that the wonderful, pure, tranquil and enlightened Mind, which is the source of all conceptions of manifested phenomena, should have no essence of itself?" (2)
In my view, the phrases "one common essence" and "primal essence" suggest knowledge of God.
To the best of my knowledge, the Buddha used Vipassana meditation to look ever more deeply into the structure of his own mind, and, when he reached the point where no wave (or vritti) arose in it, he saw his own "essence" or "nature." Having seen it, he could declare:
"The Essential Intuitive Mind [possesses] its own mysterious Enlightening Nature, and … the attainment to this Essential Intuitive Mind unveils this mysterious Enlightening Nature." (3)
I take this "mysterious enlightening nature" again to be God.
According to him, were there no God, "primal essence" or "mysterious enlightening nature," there could be no possible escape from the self with its threefold suffering of sickness, old age, and death. He describes that "essence" with negatives.
"Monks, there is a not-born, a not-become, a not-made, a not-compounded. Monks, if that unborn, not-become, not-made, not-compounded were not, there would be apparent no escape from this, here, that is born, become, made, compounded." (4)
Keep in mind that the Buddha, by the time he left for the forest, had already studied with great Hindu saints. He had by then achieved Brahmajnana, the enlightenment that comes with the rise of the kundalini to the Seventh or Crown Chakra. Yet he still detected movement in the mind and remained unsatisfied.
He turned down the offer of his guru to become his successor and inherit the ashram, preferring instead to become a mendicant and finish the work of enlightenment.
During his sojourn in the forest, he set out to eliminate all waves in the mind and, when he did so, he achieved a level of enlightenment which I believe to have been sahaja samadhi (although I could be wrong). It is a permanent state of enlightenment. It occurs when the kundalini passes beyond the Seventh Chakra and comes to rest in the spiritual heart or hridayam (not the Fourth or Heart Chakra).
In my opinion, other achievers of sahaja include Sri Ramana Mahasrshi, Bernadette Roberts, Franklin Merrell-Woolf, and Adyashanti.
The Buddha could now say "I have obtained deliverance by the extinction of self." (5)
If he had only attained Brahmajnana, the "self" he extinguished would be the "lower self" or ego. But the self he transcended was more than that. He had extinguished the Higher "Self" and attained what Bernadette Roberts called the "No-Self." This the Buddha referred to as "supreme Enlightenment." (6)
Referring to her own experiences, Bernadette Roberts, another modern-day Buddha, explains that level of enlightenment this way:
"I came upon a permanent state in which there was no self, not even a higher self, a true self, or anything that could be called a self. Clearly, I had fallen outside my own, as well as the traditional, frame of reference when I came upon a path that seemed to begin where the writers on the contemplative life had left off." (7)
The Buddha's guru was unable to take him past Brahmajnana so the Buddha needed to go off into the forest to complete his journey. Two millennia later, Bernadette Roberts was unable to find a teacher who could help her complete the journey, and, like the Buddha before her, went off into the forest and finished the task herself. (8)
(1) The Buddha in Dwight Goddard, A Buddhist Bible. Boston: Beacon Press, 1966; c1938, 283.
(2) Ibid., 126.
(3) Ibid., 182.
(4) The Buddha in Trevor Ling, The Buddha's Philosophy of Man. Early Indian Buddhist Dialogues. London, etc.: Dent, 1981, xiii. (Hereafter BPM.)
(5) The Buddha to Upaka, the first monk he met after enlightenment, in Paul Carus, The Gospel of Buddha According to Old Records. Tucson: Omen Press, 1972, 37.
(6) The Buddha in BPM, 154.
(7) Bernadette Roberts, The Experience of No-Self. A Contemplative Journey. Boston and London: Shamballa, 1985, 10. (Hereafter ENS.)
(8) See Bernadette Roberts, ENS and Path to No-Self. Boston and London: Shamballa, 1985.


text:
About Jeff Masters
Cat 6 lead authors: WU cofounder Dr. Jeff Masters (right), who flew w/NOAA Hurricane Hunters 1986-1990, & WU meteorologist Bob Henson, @bhensonweather
By: Dr. Jeff Masters , 3:43 PM GMT on May 28, 2009
Nature is jumping the gun a bit this year, with the season's first tropical depression forming four days before the official start to hurricane season. The area of disturbed weather (91L) that we've been watching, about 250 miles east-northeast of Cape Hatteras, North Carolina, has developed enough heavy thunderstorm activity and spin to be classified as a tropical depression. QuikSCAT imagery from last night revealed a closed surface circulation, but top winds of only 20 - 25 mph. Satellite estimates (using a cloud pattern recognition method called the "Dvorak" technique) were saying this was a tropical depression this morning, though, so the NHC elected to upgrade the system.
The disturbance is over the relatively warm waters of the Gulf Stream (25°C) and has wind shear of 5 - 10 knots over it, and these conditions are marginally favorable for some slow development to occur until Friday, when the system will likely move over waters too cold to support intensification. TD One is not a threat to any land areas. I give the storm a 60% chance of becoming Tropical Storm Ana.
Figure 1. Latest satellite image of TD One.
Is the formation of TD One a harbinger of an active hurricane season?
Probably not. Early season storms occurring near the U.S. coast have not been shown to be correlated with an active main portion of hurricane season during August - October. However, the situation is different if we start getting June and July storms in the deep tropics between Africa and the Lesser Antilles Islands. This was the case last year, when the formation of Hurricane Bertha in the deep tropics in July presaged an active 2008 hurricane season. According to the Hurricane FAQ, "as shown in (Goldenberg 2000), if one looks only at the June-July Atlantic tropical storms and hurricanes occurring south of 22°N and east of 77°W (the eastern portion of the Main Development Region [MDR] for Atlantic hurricanes), there is a strong association with activity for the remainder of the year. According to the data from 1944-1999, total overall Atlantic activity for years that had a tropical storm or hurricane form in this region during June and July have been at least average and often times above average. So it could be said that a June/July storm in this region is pretty much a "sufficient" condition for a year to produce at least average activity."
Portlight.org offering relief to Florida flood victims
Tropical disturbance 90L dropped as much as two feet of rain over Northeastern Florida last week, causing severe flooding. In Volusia County, at least 1500 homes were damaged by the flooding, and many of these were in low-income housing projects where the residents did not have flood insurance. Portlight Strategies, Inc., is now working to assist in this area by providing durable medical equipment to the disabled, elderly, or injured that have lost equipment due to the flooding. Equipment will also be provided to local shelters and other organizations working with flood victims. To help out, visit the Portlight disaster relief blog..
Figure 2. Rainfall amounts over Florida for the two weeks ending on May 27, 2009. Images credit: NOAA.
Jeff Masters
The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.
Cat 6 lead authors: WU cofounder Dr. Jeff Masters (right), who flew w/NOAA Hurricane Hunters 1986-1990, & WU meteorologist Bob Henson, @bhensonweather


text:
Nonprofit organizations and communities in need are benefiting from philanthropic giving trends, but whether these trends will persist is an open question.
Last week, the National Committee for Responsive Philanthropy released four new studies involving 1,121 foundations in its Philanthropic Landscape series on key foundation giving trends.
One study showed that the biggest U.S. foundations gave $10 billion in grants to benefit underserved communities.
The share of foundation grant dollars given to benefit the poor, the elderly, women and other marginalized groups increased to 42%, up from the 40% average in 2008–2010.
However, a second report noted that foundation funding aimed at social justice—engaging disenfranchised groups in addressing their problems—declined to 12% of total grant dollars in 2011. Foundations gave $2.9 billion for that purpose.
The share of grant dollars reported as core support leapt from 16% in 2008–2010 to 24% in 2011. NCRP said in a statement that this was the first time it had documented such a large increase in the proportion of grant dollars classified as general operating support.
Another report in the series showed that about 90% of foundations did not report any multiyear funding; this was consistent with earlier analyses of such giving.
"There are some hopeful signs that more foundations are giving in ways that benefit those that need philanthropic support the most," Aaron Dorfman, NCRP's executive director, said in the statement.
"But only time will tell if the trend holds in the next several years."
Other findings from the studies included the following:
- Foundations in the South were less likely to report giving to benefit underserved communities, but one in five funders nationally provided at least 50% of grant dollars in this way.
- Although the share of reported grant dollars serving a social justice purpose declined in 2011, among those grant makers that did provide such funding the median rose from 4% to 7%.
- Family foundations, Southern foundations and funders giving between $5 million and $10 million were likelier to provide general operating support. Eleven percent of the current sample reported providing 100% of their grant dollars as core support.
- Among those foundations that did report providing multiyear funding commitments, such giving was consistent and at high levels. However, only 5% of the sample reported at least 50% of grant dollars as funding beyond one year.
Read IRS Scandal Has Charities Worrying About 'Collateral Damage' on AdvisorOne.


text:
Thank You for Subscribing!
For Cool Weekly Traffic Tips, 'Like' our Fan Page Below…
Your PDF should arrive in your email inbox within the next 5 minutes.
If you'd like to stay updated with the latest traffic tricks, tips, and updates – 'Like' our Facebook page to the left. This is where I share some of my best traffic tips :)
"Kentucky" Kim


text:
Your Neighbor: Bob Meakin rids homeowners of pesky pests
MUNNSVILLE >> Bob Meakin never knows exactly what kind of crawling, winged, fanged or smelly creature he will find on his next day at work.
Meakin owns Captor Wildlife Services, Inc., a professional wildlife management company he started in 1989 to assist area residents with unwanted visitors. His most common cases involve bats, birds, chipmunks, moles, voles, muskrats, raccoons, skunks, squirrels and woodchucks, but he said in his two decades-plus he has dealt with a wide range of pests.
"It really runs the gamut of what bothers people, and the smaller the animal, the bigger the problem. Smaller places where animals are finding access are harder to find," Meakin explained.
Meakin said his service begins with a telephone call -- and some can be quite frantic.
One woman contacted him saying it sounded like someone was trying to break in her roof. There was a banging noise outside, but every time the caller went out it to see what it was the sound stopped.
Luckily, when Meakin arrived on the scene there had been a light snow so he could find tracks -- they turned out to be from crows that had flown away every time the woman came near. He followed the tracks to the metal gutter, and found a peanut frozen inside.
The crows had spotted the peanut -- most likely left over from someone feeding the squirrels nearby, carried by birds to the rooftop, and then dropped to roll into the gutter -- and were pecking at it to try to get it loose.
"Once she knew what it was it wasn't a problem any more. Knowledge is power," Meakin said.
Another caller began their conversation by whispering to him that there was something inside the chimney. Meakin began whispering back, but then asked the caller why they were talking so quietly over the phone.
She told him she was hearing a loud noise inside the chimney. There were blizzard conditions outside that day, so Meakin didn't immediately make it to the house. He advised her to make sure the fireplace door and the damper were closed, and he would come out as soon as he could.
There did end up being a raccoon inside the chimney, and once it was back outside Meakin installed a chimney cap to keep it out. He felt around inside the flue from inside the room, and found a chunk of loose mortar -- that was what the raccoon was batting around inside that was making so much noise.
Another recent caller even frantically told him about a group of ducks trying to cross a roadway, asking that he come down and make sure the ducks got where they were going safely. Meakin doesn't really answer those kind of "emergencies," he admitted, and told that caller to simply stop traffic while the ducks crossed.
"That's really the influence of television -- there's not really likely to be anybody you can call to come to the rescue of ducks like that," he said.
Meakin said many of his callers haven't actually seen anything yet when they initially contact him, but rather just heard a noise. That isn't usually much help in diagnosing the problem, he admitted.
"You can't see sound," he said. "It's tough to guess what it is from the description of a noise."
He asks when and where the noise might have been heard, and sets up an onsite investigation to truly discern exactly what is going on and if it is indeed an animal. If something is found, Meakin and the caller work out a plan to eliminate the problem according to their desires.
Most of his work is exclusion, where the animal is driven from the place it shouldn't be via a system much like a check valve. It allows it to go out, but not back in. The point of entry is sealed and the unwanted guest goes away to find shelter or food someplace else. This is not used when there is a possibility of separating a female from her babies, Meakin added.
Actual trapping and relocation is not usually a viable option, because he needs the permission of the land owner before he can take an animal elsewhere.
"In the real world this doesn't work," he said. "People misconceive that if I move an animal it will be happier someplace else. Plus you never can tell the condition of the animal, and you can transfer an animal's sickness to another area. I'd really just be taking the problem someplace else."
During his investigation, he tries to find the places where the animal is getting inside, and what brings the critters to that place, like whether there is some kind of food attracting them. Bird feeders are one of the biggest culprits in bringing in unwanted wildlife guests, Meakin said.
Flaws in construction and unfixed damages often provide nice entry places for the animals to get in, he warned.
"Many times animals just exploit our mistakes," Meakin said. "If someone doesn't fix the trim where the wood is rotten, birds and squirrels can get in. Animals aren't stupid -- they just don't read. They have a more primordial intelligence and a life and death struggle every day just to survive."
After the problem with the pest is eliminated, Meakin also performs needed renovations to ensure the infestation won't happen again. He said he tries to leave homes looking even better than they were when he arrived, making sure the repairs blend in with the rest of the construction as best as possible.
Meakin said to prepare for possible painful encounters, he has a series of three pre-exposure rabies vaccines, plus regular physicals to test for the proper amounts of antibodies in his blood to ward off any infection from an animal bite or scratch. He said his education in the habits of animals and how they will react when confronted is often enough to keep him safe.
"People get hurt when they don't know what an animal is going to do, and they don't know what they themselves are going to do," Meakin said. "Animals generally don't want to confront people. It's only when you get in their way that they will be aggressive.
Not knowing what kind of animal challenge he will encounter next is the best part of running Captor Wildlife Services, he noted.
"I really enjoy all of the variety in this job. I get to deal with different people who often have complaints about common animals, but where those animals go and how they got in there is unique," Meakin explained.
Captor Wildlife Services is New York state licensed and fully insured. For more information, call Meakin at 495-5561 or log on to www.captorwildlife.com


text:
PublicityThe BBC have released their first publicity photo of Matt Smith and Jenna-Louise Coleman together on location, which is available to download as wallpaper in both 4:3 and 16:9 format:
Further images of the pair are due on the BBC website next week.
Filming UpdateMeanwhile, filming has continued on the series, with Matt and Jenna seen together on location at Margam Country Park last week. A clapperboard confirmed that this episode is being directed by Jamie Payne and Director of Photography is Mike Southon.
Filming took place over a couple of days, with scenes involving characters dressed in Victorian attire and in 'spooky' parts of the park. This was the first time Jenna had been seen in 'costume', and it was also reported that her character is called Clara, confirming the name rumoured back in March.
With thanks to Ryan Farrell, Phillipa Collins and Steven Price - click on their links for more photos.
With thanks to Ryan Farrell, Phillipa Collins and Steven Price - click on their links for more photos.
Filming then returned to another old haunt for the weekend, with the interiors of Hensol Castle playing host to the cast and crew.
Wednesday saw a read-through take place, as reported by casting director Andy Pryor: "Mega readthrough day, Block 1 of Call The Midwife (fantastic to be back) and a marv new Doctor Who ep. No spoilers for either!" This was followed yesterday by an early morning scene taking place in the Plan Cafe in Cardiff and featuring Matt with series regular Barnaby Edwards - normally enclad within a Dalek, the actor commented: "It's a welcome change not to be in one for this. :)"
With thanks to Dan Wills, Gareth Bundy and @CardiffTimelord - click on links for more photos.
This week also saw a surprising couple appear on location - Karen Gillan and Arthur Darvill! The pair officially completed filming in May but were back for interior pickups for their last episode. Additional exterior work on episode four continued with scenes with Matt Smith outside the former couple's "home". Scenes were directed by Saul Metzstein and Douglas Mackinnon, with director of photography Sarah Bartles-Smith.
Filming took place back at Church Road in Penarth (Amy/Rory house interiors) and at Bute Esplanade (Amy/Rory house exteriors), with Ood pieces spotted at the former! Scenes were believed to be pickups for those that couldn't be completed before due to weather conditions (not that this had improved much since then!). Some dialogue overheard helped set the (probable) context of the Ood: "Hello Pond, me again...I've dropped your Ood back home, he's been missing his Hive Mind. Yeah... The Helmic Regulator's on the blink again, it got hit by an arrow!"
With thanks to @CardiffTimelord, Gareth Bundy and Ryan Farrell - click on their links for more details and photos.
With thanks to @CardiffTimelord, Gareth Bundy and Ryan Farrell - click on their links for more details and photos.


text: It's no secret how I feel about the upcoming Michael Bay-produced Ninja Turtles movie. And despite the involvement of one of the Teenage Mutant Ninja Turtles co-creators, Kevin Eastman (a creative consultant), I'm just really, really skeptical about this movie. But Eastman says that the filmmakers are bent on making this something that we fans will accept -- and he's looking to the hugely successful, widely appealing cinematic style of The Avengers for inspiration. Is that so? Well, I suppose that if you consider that the Avengers movie didn't include a couple of the original Avengers from the Marvel comics, that's on par with completely changing the origin story of the title characters and turning them into different creatures altogether. Like turning Thor into Spider-Man. Something like that? No big deal. Read the rest