33610569
Compression-based broadcast strategies in wireless information systems
Data delivery is through broadcast in wireless information systems due to the asymmetric communication property. However, broadcasting data easily wastes large access time because the large amount of data pages needs to be broadcast. In this paper we propose three compression-based strategies considering access order to reduce access time. Then, the expected access time of three proposed strategies is also derived by using the probability model. Our analytic and experimental results show that the compression-based broadcast strategies can dramatically reduce the access time for mobile users (MU).
31930663
Minimization of resource consumption for multidatabase query optimization
Due to the autonomy of individual databases, a multidatabase system (MDBS) has no control over the task execution within each database system. This complicates the issue of query optimization in a MDBS. Past researchers tackled this problem mainly by regenerating the cost model of each participating database systems. However a completely autonomous participating database system does nor own the information (data) as well as the mechanism (software) for converting data of one database to another to resolve the data type conflict problems that can occur in any MDBS environment. In addition, unpredictable factors that can drastically deviate the accuracy of a regenerated cost model (in the past research) come into play at unknown time. This confines the processing of an intersite operation (such as a join over two relations of different databases) to the MDBS only. The participating database systems will not be able to share the workload of the MDBS under this circumstance. Hence, minimizing the consumption of system resources of the MDBS is an urgent problem. The authors propose three scheduling algorithms that are used in the MDBS to reduce the processing cost of a multidatabase query. A major difference between the strategies and the past methods is that ours do not require the knowledge of the cost models of the participating databases.
2051959
Performance Evaluation of Forwarding Strategies for Location Management in Mobile Networks
This paper presents a methodology for evaluating the performance of forwarding strategies for location management in a personal communication services (PCS) mobile network. A forwarding strategy in the PCS network can be implemented by two mechanisms: a forwarding operation which follows a chain of databases to locate a mobile user and a resetting operation which updates the databases in the chain so that the current location of a mobile user can be known directly without having to follow a chain of databases. In this paper, we consider the PCS network as a server whose function is to provide services to the mobile user for ‘updating the location of the user as the user moves across a database boundary’ and ‘locating the mobile user’. We use a Markov chain to describe the behavior of the mobile user and analyze the best time when forwarding and resetting should be performed in order to optimize the service rate of the PCS network. We demonstrate the applicability of our approach with hexagonal and mesh coverage models for the PCS network and provide a physical interpretation of the result.
34408109
Modeling GIS Data Using OMEGA
20308502
Object signatures for supporting efficient navigation in object-oriented databases
Most methods that have been proposed to improve query processing in object-oriented databases are designed for the aggregation hierarchy. Although the structure of the generalization hierarchy is similar to the aggregation hierarchy, techniques developed for the aggregation hierarchy cannot fully use the characteristics of the generalization hierarchy to improve performance. We devise a new object signature for the generalization hierarchy. The object signature consists of two parts: a reference signature and a structure signature. The former can be used to eliminate objects that do not match the nested predicates specified in the query, and the latter can be used to eliminate objects that do not belong to the target classes. We propose some processing methods using the object signatures for queries that involve generalization hierarchies. In addition, we define cost models of the object signature and then compare the performance of the traditional query processing method with the object signature method. The results show that using the object signatures can effectively reduce the number of disk accesses in a query.
46069080
A Graph-Theoretic Model for Optimizing Large Join Queries
12792008
Software management
Software management problems? In this session presenters will discuss and demonstrate how Pima Community College (PCC) reigned in control of the software on 5,550 desktop and portable computers located over six campuses, two district offices, and nine center locations.To combat the lack of software standards and perceived legality issues, PCC developed a software plan with input from faculty, staff, and administrators. Prior to implementation of this plan, all users could purchase, download, or share software at will. During this session you will learn how PCC developed the plan and overcame many obstacles including: support issues, auditing and verification, compatibility, user adoption, license agreements, and plan enforcement. In addition, you will learn about IT staff certification and training.Since implementation PCC has enjoyed many benefits including; bulk or volume purchasing, up to date software, college-wide site license agreements, improved standards, reduced need for helpdesk support, consistency between locations, higher user awareness, and increased IT staff credibility.
7718842
Averaging attack resilient video fingerprinting
This paper addresses an effective technique for digital fingerprinting for video. The code modulation technique, that uses an averaging collusion resilient fingerprint code derived from BIBD, is a robust method against averaging attacks. In this paper, we propose a new fingerprint code based on GD-PBIBD theory that is efficient in designing the fingerprint code and describe an effective method to embed and detect the fingerprint code, in which the merits of orthogonal modulation and coded modulation techniques are combined. To analyze the performance, we apply our method to video applications using a spread-spectrum watermarking technique in the spatial domain and the results show the proposed method is effective for fingerprint code embedding and detection.
33340433
An evolutionary approach to the job-shop scheduling problem
This paper focuses on the heuristic hybridization and the genetic search as a methodology to develop a computationally efficient heuristic for the job-shop scheduling problem (JSP). In order to adapt the JSP to a genetic algorithm (GA), the ASGPL (Active-Schedule Generation with a Priority-List) algorithm with a hopping scheme was proposed, and using a GA, an iterative schedule improvement procedure called EVIS (Evolutionary Intracell Scheduler) was designed. The genetic search in EVIS was parallelized with a model of subpopulations and migration. Without implementing any problem-tailored heuristic for the job-shop scheduling problem, EVIS was able to find optimal solutions to a number of different problem instances in reasonable computation time.<<ETX>>
203663688
Practical Solutions for QoS-Based Resource Allocation
An apparatus and method is disclosed for forming a liquid-tight container having a rectangular cross-section formed from a one-piece, T-shaped blank of paperboard material. The carton preferably includes an access flap and straw element on one side thereof which, when manually lifted, exposes an end of the straw element from which the contents of the carton may be consumed by a user. The apparatus is compact in nature, possessing relatively few transport mechanisms which advance the T-shaped carton blank through a plurality of work stations. A novel method and apparatus for serially applying the straw element and access panel to the carton blank is disclosed, wherein the straw element and a length of polyethylene coated Mylar tape is automatically bonded to the carton blank upon a rotating heat sealing and alignment drum. A conveyor for collating a plural number of the carton blanks about a forming mandrel is also provided, and is positioned transversely to the remainder of the apparatus thereby significantly reducing the overall size of the apparatus. An ultrasonic welder bonds the side seams and end closure panels of the container upon a rotating crossbar mandrel which eliminates any misalignment during the sealing process. A substantially rigid conveyor transport carries a plurality of the carton blanks through pre-form, filler, and end closure work stations, and includes plural anvils for the ultrasonic welding process. An ejector mechanism is additionally provided which ejects the filled carton blanks from the rigid conveyor along a dual direction path, thereby eliminating the possibility of creasing or puncturing the filled and sealed container. The apparatus of the present invention additionally accommodates the production of differing size containers with only minor adjustments.
5358328
Teletraffic Performance of Mobile Radio Networks with Hierarchical Cells and Overflow
Wireless mobile networks, comprising a hierarchical layer of cells, use the cell layering to provide alternate routing for calls. This paper proposes a model for multilayered wireless mobile communications networks that provides a unified treatment of overflow to account for intra- and interlayer overflow. This takes account of the inherent overlap between cells in the same layer and between layers, and hence the prospect of controlling the overflow to achieve a tradeoff between new call and handover performance. The mobility of users within the layers is included in the model, and this allows handover performance to be estimated. Network performance is evaluated in terms of caller-perceived performance by calculating the probability of call failure using a Markov chain model of call progress. An example is presented that provides a comparison of the network performance for a range of overflow policies. The main contribution of this paper is the development of an analytic method that treats overflow in a unified manner. This allows the approximate performance of overflow strategies that balance the need to maintain calls in progress with the desire to accept more new calls to be evaluated for large networks.