2439055
Active brokers and their runtime deployment in the ECho/JECho distributed event systems
This paper introduces active brokers and third-party derivation, which is the basic programming construct for run-time remote broker deployment, in the ECho/JECho distributed event systems. We describe its implementation in the JECho system and give examples of using it in ECho/JECho distributed event systems. In particular, we describe the use of third-party derivation in supporting the scalability of content-based event delivery. Specifically, third-party derivation is used both to dynamically construct content-based event distribution trees and to offload potentially expensive client-specific event routing/processing by the run-time creation of remote brokers. Our preliminary benchmark results demonstrate the significant benefits of using third-party derivation.
17733083
SML Model-based Management
Models enable a clear separation between domain knowledge and application-specific details. In the system management arena, there are multiple implementations of model-based system management solutions, but until now, there was no industry-wide agreement on a common language or paradigm to enable interoperability. A new standard has been proposed to describe IT Services, the service modeling language ("SML"). While SML enables interoperability, it still poses challenges in terms of scalable model stores, model validation, and use. This paper discusses an architecture for SML model management and validation and describe and evaluate a prototype implementation with a use case on system management of PlanetLab.
2517295
Automated Availability Management Driven by Business Policies
Policy-driven service management helps reduce IT management cost and it keeps the service management aligned with business objectives. While most of the previous research focuses on performance/resource managements, little has been researched in the area of availability management driven by business policies. This is a critically important task in enterprise IT, because a single failure in enterprise IT could cause huge business loss. It is still unclear how we can automate the availability management in a highly dynamic and complex system according to business level objectives for performance and risk attitude/preference. As a consequence, users can not manage the availability/performance ratio to match their risk tolerance. In this paper, we propose a policy-driven approach to automate run-time availability management in IT systems, according to high level availability and performance objectives. We further apply von Neumann-Morgenstern utility theory to deal with users' risk attitude policies, an important class of business policies specific for availability management, and the associated preference structures. Based on the proposed approach, we implement an automated decision engine for availability management. The initial evaluation of the solution illustrates the significance of the policy-driven approach and it demonstrates its applicability for availability management in complex IT environments. This way IT users can customize their availability to the risks tolerable by business objectives.
7576060
Specification-Enhanced Policies for Automated Management of Changes in IT Systems
Enterprise and grid computing systems are complex and subject to a broad range of changes such as configuration updates, failures, and performance degradations. These changes affect infrastructure elements such as computation and storage nodes, applications, and system management elements such as monitoring infrastructures. Today's best practices in use by system administrators to manage these changes are manual and ad-hoc. In large complex installations, this would lead to high operational costs, broken closed loop automation, and reduced agility. Providing tools and mechanisms to administrators that automate the reaction to these changes is highly desirable and is an active research area. 
 
Policy-based management using Event-Condition-Action (ECA) rules is a well-known approach for such automated change management where management actions are executed when specified event-conditions are observed. In complex systems, the interdependence of components generates multiple events when a single change happens causing multiple rules to be triggered. The order of execution of rule actions determines the system behavior necessitating reasoning about execution order. ECA rules do not contain explicit action specifications needed for reasoning and are therefore unsuited for specifying management rules. 
 
In this paper, we propose a specification-enhanced ECA model called Event-Condition-Precondition-Action-Postcondition (ECPAP) for designing adaptation rules. ECPAP rules contain action specifications in first order predicate logic enabling us to develop reasoning algorithms to determine enforcement order of multiple rules. The enforcement order is represented as a Boolean Interpreted Petri Net workflow. We introduce a new notion called enforcement semantics that provides guarantees about rule ordering. We have built an adaptation framework using ECPAP model and have demonstrated it for automated change management of Ganglia and HP OpenView monitoring systems. The evaluation of the framework illustrates the significance of the ECPAP model and demonstrates its applicability for managing complex IT environments.
11444892
A prototype implementation of archival Intermemory
An Archival Intermemory solves the problem of highly survivable digital data storage in the spirit of the Internet. In this paper we describe a prototype implementation of Intermemory, including an overall system architecture and implementations of key system components. The result is a working Intermemory that tolerates up to 17 simultaneous node failures, and includes a Web gateway for browser-based access to data. Our work demonstrates the basic feasibility of Intermemory and represents signi cant progress towards a deployable system.
33065239
Triangle-free Hamiltonian Kneser graphs
The Kneser graph K(n,k) has as vertices the k-subsets of {1, 2,...,n}. Two vertices are adjacent if the k-sets are disjoint. When n > 3k, the Kneser Graph K(n, k) has no triangle. In this paper, we prove that K(n,k) is Hamiltonian for n ≥ (3k + 1 + √5k2- 2k + 1)/2, and extend this to the bipartite Kneser graphs. Note that (3k + 1 + √5k2 - 2k + 1)/2 > 2.62k + 1.
4357183
A New Proof of Wojcicka's Conjecture
A graph G is 3-domination-critical if its domination number γ is 3 and the addition of any edge decreases γ by 1. Wojcicka conjectured that every 3-domination-critical graph with δ ≥ 2 has a hamiltonian cycle (J. Graph Theory 14 (1990) 205-215). The conjecture had been proved and its proof consists of two parts: the case α ≤ δ + 1 (J. Graph Theory 25 (1997) 173-184) and the case α = δ + 2 (Discrete Appl. Math. 92 (1999) 57-70). In this paper, we give a new and simple proof of the conjecture by using Hanson's (J. Combin. Math. Combin. Comput. 13 (1993) 121-128) and Bondy-Chvatal's (Discrete Math. 15(1976) 111-135) closure operations.
9049589
A service-oriented modeling and simulation framework for rapid development of distributed applications
Abstract The paper presents a service-oriented distributed modeling and simulation framework that supports the development and evaluation of large scale distributed systems such as network-centric and system-of-systems applications. The distinct features of the framework include a modeling and specification language, dynamic model checking for completeness and consistency, automated code generation from the specification, simulation of different architectures with a template-based platform builder, service-oriented multi-agent simulation for easy re-configuration and re-composition, formal policy specification and enforcement for dynamic verification, and dynamic analyses for evaluation and monitoring. The framework and most of the tools reported in this paper have been implemented and applied in several industrial projects. This paper presents the design principles, user interfaces, its runtime infrastructure, and the experiment results on its performance.
9429595
Relay feedback tuning of robust PID controllers with iso-damping property
A new tuning method for proportional-integral-derivative (PID) controller design is proposed for a class of unknown, stable, and minimum phase plants. We are able to design a PID controller to ensure that the phase Bode plot is flat, i.e., the phase derivative w.r.t. the frequency is zero, at a given frequency called the "tangent frequency" so that the closed-loop system is robust to gain variations and the step responses exhibit an iso-damping property. At the "tangent frequency", the Nyquist curve tangentially touches the sensitivity circle. Several relay feedback tests are used to identify the plant gain and phase at the tangent frequency in an iterative way. The identified plant gain and phase at the desired tangent frequency are used to estimate the derivatives of amplitude and phase of the plant with respect to frequency at the same frequency point by Bode's integral relationship. Then, these derivatives are used to design a PID controller for slope adjustment of the Nyquist plot to achieve the robustness of the system to gain variations. No plant model is assumed during the PID controller design. Only several relay tests are needed. Simulation examples illustrate the effectiveness and the simplicity of the proposed method for robust PID controller design with an iso-damping property.
17883721
Classification of self-consumable highlights for soccer video summaries
An effective scheme for soccer summarization is significant to improve the usage of this massively growing video data. The paper presents an extension to our recent work which proposed a framework to integrate highlights into play-breaks to construct more complete soccer summaries. The current focus is to demonstrate the benefits of detecting some specific audio-visual features during play-break sequences in order to classify highlights contained within them. The main purpose is to generate summaries which are self-consumable individually. To support this framework, the algorithms for shot classification and detection of near-goal and slow-motion replay scenes is described. The results of our experiment using 5 soccer videos (20 minutes each) show the performance and reliability of our framework