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Articles 3811 - 3840 of 4425

Full-Text Articles in Software Engineering

Best Practices For Implementing Agile Methods: A Guide For Department Of Defense Software Developers, Ann L. Fruhling, Alvin E. Tarrell Jan 2007

Best Practices For Implementing Agile Methods: A Guide For Department Of Defense Software Developers, Ann L. Fruhling, Alvin E. Tarrell

Information Systems and Quantitative Analysis Faculty Publications

Traditional plan-driven software development has been widely used in the government because it's considered to be less risky, more consistent, and structured. But there has been a shift from this approach to Agile methods which are more flexible, resulting in fast releases by working in an incremental fashion to adapt to the reality of the changing or unclear requirements.

This report describes the Agile software development philosophy, methods, and best practices in launching software design projects using the Agile approach. It is targeted to Defense Department software developers because they face broad challenges in creating enterprise-wide information systems, where Agile …


An Evaluation Of Omg Sysml 1.0a Standard Conformance Between Modelling Tools, Andrew James Campbell Jan 2007

An Evaluation Of Omg Sysml 1.0a Standard Conformance Between Modelling Tools, Andrew James Campbell

Theses : Honours

The SysML is a recent introduction to modelling languages for the systems engineering domain. Modelling tools are offering support for its notation. Studies related to the UML have indicated that modelling tools lack compliance to the UML language. This issue may apply equally to the SysML and the aim of this research is to investigate that language compliance issue. The first phase of this research is concerned with the compliance of current modelling tools to the SysML l.0a Final Adopted Specification (PAS). It consists of a comparative evaluation of candidate tools based on an ideal framework derived from the language …


Sub Space: Enhancing The Spatial Awareness Of Trainee Submariners Using 3d Simulation Environments, Michael Garrett Jan 2007

Sub Space: Enhancing The Spatial Awareness Of Trainee Submariners Using 3d Simulation Environments, Michael Garrett

Theses : Honours

Rapid advancements in computer technology have facilitated the development of practical and economically feasible three dimensional (3D) computer-generated simulation environments that have been utilized for training in a number of different fields. In particular, this development has been heavily influenced by innovations within the gaming industry, where First Person Shooter (FPS) games are often considered to be on the cutting edge of gaming technology in terms of visual fidelity and performance. 3D simulation environments built upon FPS gaming technologies can be used to realistically represent real world places, while also providing a dynamic and responsive experiential based learning environment for …


Development Of Integrated Process Simulation System Model For Spent Fuel Treatment Facility (Sftf) Design, Yitung Chen, Sean Hsieh Jan 2007

Development Of Integrated Process Simulation System Model For Spent Fuel Treatment Facility (Sftf) Design, Yitung Chen, Sean Hsieh

Separations Campaign (TRP)

The major objectives will lead to a creation of framework that combines all the strengths of AMUSE’s complicated calculations, well-established commercial system process package and ISOPro’s flexible parameter optimization modules. Development of the process simulation code can be done using the solvent extraction process at Argonne National Laboratory in collaboration with the research team from Mechanical Engineering Department at UNLV.

Research accomplishments:

  • Integrated the ASPEN-Plus process model with the ISOPro system engineering modeling package, developed by the UNLV team.
  • Tested the simplified system process integration using the ISOPro package.
  • Generated complete version of the ISOPro package user manual and tutorial. …


Businessfinder: Harnessing Presence To Enable Live Yellow Pages For Small, Medium And Micro Mobile Businesses, D. Chakraborty, K. Dasgupta, S. Mittal, Archan Misra, C. Oberle, A. Gupta, E. Newmark Jan 2007

Businessfinder: Harnessing Presence To Enable Live Yellow Pages For Small, Medium And Micro Mobile Businesses, D. Chakraborty, K. Dasgupta, S. Mittal, Archan Misra, C. Oberle, A. Gupta, E. Newmark

Research Collection School Of Computing and Information Systems

Applications leveraging network presence in next-generation cellular networks have so far focused on subscription queries, where "presence" information is extracted from specific devices and sent to entities who have subscribed to such presence information. In this article we present BusinessFinder, a service that leverages the underlying cellular presence substrate to provide efficient, on-demand, context-aware matching of customer requests to nomadic micro businesses as well as small and medium businesses having a mobile workforce. Presence, in the context of BusinessFinder, is not simply limited to phone location and device status, but also encompasses dynamic attributes of vendors (both "mobile" and "static"), …


Cache Coherence Protocol Verification Using Ωmega, Ki Yung Ahn Jan 2007

Cache Coherence Protocol Verification Using Ωmega, Ki Yung Ahn

Computer Science Faculty Publications and Presentations

We verify some correctness properties of the DASH cache coherence protocol using Ωmega. Ωmega is a language with a rich type system featuring GADTs, type functions, and user-guided type checking rules. Cache coherence protocols have both safety properties and liveness properties. We show how to describe some of the safety properties of DASH cache coherence protocol in mega. Since liveness properties are not easily expressed by types, we investigate invariants sufficient to imply some of the liveness properties of concern, and assert those invariants as well in the type system of Ωmega. Using Ωmega, we can have both a working …


A Comparison Of Edge Detection Methods For Segmentation Of Skin Lesions In Mobile-Phone-Quality Images, Khanh Linh Hua Jan 2007

A Comparison Of Edge Detection Methods For Segmentation Of Skin Lesions In Mobile-Phone-Quality Images, Khanh Linh Hua

Theses : Honours

The world is faced with a rapidly increasing number of skin cancers every year. Melanoma is the most deadly type of skin cancer though it can be treated if it has been detected at an early stage. However, there is a shortage of dermatologists in rural areas. The increasing number of camera phones, together with improved coverage in rural areas gives some potential for tele-dermatology, whereby people with no local access to a dermatologist can send images of suspicious skin lesions to an expert for assessment. Merely relaying images to a human expert solves only part of the problem, there …


Developing A Java Application To Assist Conceptual Modeling For Discrete-Event Simulation (Cms-Proto), Wei Ling Chang Dec 2006

Developing A Java Application To Assist Conceptual Modeling For Discrete-Event Simulation (Cms-Proto), Wei Ling Chang

All-Inclusive List of Electronic Theses and Dissertations

Simulation is a useful tool that helps managers and engineers model and analyze the behavior of real systems. In business or industry, decision makers can efficiently and effectively make critical decisions by using simulations to design models and test possible solutions. Using simulation can reduce cost, improve quality and productivity, make effective process design, and shorten time to market. However, conducting simulation study requires kl).owledge of application, simulation and implementation domains, and there is a lack of tools to help modelers efficiently transform and integrate knowledge and information to build conceptual simulation models. This creates a gap for modelers to …


Identifying Difficulties In Learning Uml, Keng Siau, Poi-Peng Loo Dec 2006

Identifying Difficulties In Learning Uml, Keng Siau, Poi-Peng Loo

Research Collection School Of Computing and Information Systems

Despite its recognition as a standard object-oriented modeling language, Unified Modeling Language (UML) has been criticized for such deficiencies as semantic inconsistencies, vagueness, and conflicting notations. the relationship between these deficiencies and the difficulties in the learning process is the focus of this study. A concept mapping technique is used to unveil the learning difficulties and suggestions for alleviating them are provided.


Modeling Heterogeneous User Churn And Local Resilience Of Unstructured P2p Networks, Zhongmei Yao, Derek Leonard, Dmitri Loguinov, Xiaoming Wang Nov 2006

Modeling Heterogeneous User Churn And Local Resilience Of Unstructured P2p Networks, Zhongmei Yao, Derek Leonard, Dmitri Loguinov, Xiaoming Wang

Computer Science Faculty Publications

Previous analytical results on the resilience of unstructured P2P systems have not explicitly modeled heterogeneity of user churn (i.e., difference in online behavior) or the impact of in-degree on system resilience. To overcome these limitations, we introduce a generic model of heterogeneous user churn, derive the distribution of the various metrics observed in prior experimental studies (e.g., lifetime distribution of joining users, joint distribution of session time of alive peers, and residual lifetime of a randomly selected user), derive several closed-form results on the transient behavior of in-degree, and eventually obtain the joint in/out degree isolation probability as a simple …


Robust Control Techniques Enabling Duty Cycle Experiments Utilizing A 6-Dof Crewstation Motion Base, A Full Scale Combat Hybrid Electric Power System, And Long Distance Internet Communications, Marc Compere, Jarrett Goodell, Miguel Simon, Wilford Smith, Mark Brudnak Nov 2006

Robust Control Techniques Enabling Duty Cycle Experiments Utilizing A 6-Dof Crewstation Motion Base, A Full Scale Combat Hybrid Electric Power System, And Long Distance Internet Communications, Marc Compere, Jarrett Goodell, Miguel Simon, Wilford Smith, Mark Brudnak

Publications

The RemoteLink effort supports the U.S. Army's objective for developing and fielding next generation hybrid-electric combat vehicles. It is a distributed soldierin- the-Ioop and hardware-in-the-Ioop environment with a 6-DOF motion base for operator realism, a full-scale combat hybrid electric power system, and an operational context provided by OneSAF. The driver/gunner crewstations rest on one of two 6-DOF motion bases at the U.S. Army TARDEC Simulation Laboratory (TSL). The hybrid power system is located 2,450 miles away at the TARDEC Power and Energy System Integration Laboratory (P&E SIL). The primary technical challenge in the RemoteLink is to operate both laboratories together …


Icodes (Integrated Computerized Deployment System) Technical And Operational Description, Cesar Diaz, Billy Waiters, Jerry Pickard, Jason Naylor, Steven Gollery, Patrick Mcgraw, Michael Huffman, John Fanshier, Matt Parrott, Steve O'Driscoll-Packer, Boone Pendergrast, Evan Sylvester, Jens Pohl Nov 2006

Icodes (Integrated Computerized Deployment System) Technical And Operational Description, Cesar Diaz, Billy Waiters, Jerry Pickard, Jason Naylor, Steven Gollery, Patrick Mcgraw, Michael Huffman, John Fanshier, Matt Parrott, Steve O'Driscoll-Packer, Boone Pendergrast, Evan Sylvester, Jens Pohl

Collaborative Agent Design (CAD) Research Center

Over the past decade CDM Technologies, Inc. (CDM) in conjunction with the Collaborative Agent Design Research Center (CADRC) at California Polytechnic State University (Cal Poly) in San Luis Obispo, has developed a suite of information-centric software tools in support of military deployment and distribution processes. All of these tools feature agents that are capable of reasoning about data in the context provided by an internal information model. Together they represent an evolving suite of adaptive Knowledge Management Enterprise Services (KMES) that can be readily configured into a net-centric planning and decision-support toolset for a particular application domain.

As a set …


Dcma: A Label-Switching Mac For Efficient Packet Forwarding In Multi-Hop Wireless Networks, Arup Acharya, Sachin Ganu, Archan Misra Nov 2006

Dcma: A Label-Switching Mac For Efficient Packet Forwarding In Multi-Hop Wireless Networks, Arup Acharya, Sachin Ganu, Archan Misra

Research Collection School Of Computing and Information Systems

This paper addresses the problem of efficient packet forwarding in a multihop, wireless "mesh" network. We present an efficient interface contained forwarding (ICF) architecture for a "wireless router," i.e., a forwarding node with a single wireless network interface card (NIC) in a multihop wireless network that allows a packet to be forwarded entirely within the NIC of the forwarding node without requiring per-packet intervention by the node's CPU. To effectively forward packets in a pipelined fashion without incurring the 802.11-related overheads of multiple independent channel accesses, we specify a slightly modified version of the 802.11 MAC, called data driven cut-through …


Low-Latency Broadcast In Multirate Wireless Mesh Networks, Chun Tung Chou, Archan Misra, Junaid Qadir Nov 2006

Low-Latency Broadcast In Multirate Wireless Mesh Networks, Chun Tung Chou, Archan Misra, Junaid Qadir

Research Collection School Of Computing and Information Systems

In a multirate wireless network, a node can dynamically adjust its link transmission rate by switching between different modulation schemes. In the current IEEE802.11a/b/g standards, this rate adjustment is defined for unicast traffic only. In this paper, we consider a wireless mesh network (WMN), where a node can dynamically adjust its link-layer multicast rates to its neighbors, and address the problem of realizing low-latency network-wide broadcast in such a mesh. We first show that the multirate broadcast problem is significantly different from the single-rate case. We will then present an algorithm for achieving low-latency broadcast in a multirate mesh which …


Smartic: Towards Building An Accurate, Robust And Scalable Specification Miner, David Lo, Siau-Cheng Khoo Nov 2006

Smartic: Towards Building An Accurate, Robust And Scalable Specification Miner, David Lo, Siau-Cheng Khoo

Research Collection School Of Computing and Information Systems

Improper management of software evolution, compounded by imprecise, and changing requirements, along with the “short time to market ” requirement, commonly leads to a lack of up-to-date specifications. This can result in software that is characterized by bugs, anomalies and even security threats. Software specification mining is a new technique to address this concern by inferring specifications automatically. In this paper, we propose a novel API specification mining architecture called SMArTIC (Specification Mining Architecture with Trace fIltering and Clustering) to improve the accuracy, robustness and scalability of specification miners. This architecture is constructed based on two hypotheses: (1) Erroneous traces …


A Pattern Language For Extensible Program Representation, Andrew P. Black, Daniel Vainsencher Oct 2006

A Pattern Language For Extensible Program Representation, Andrew P. Black, Daniel Vainsencher

Computer Science Faculty Publications and Presentations

For the last 15 years, implementors of multiple view programming environments have sought a single code model that would form a suitable basis for all of the program analyses and tools that might be applied to the code. They have been unsuccessful. The consequences are a tendency to build monolithic, single-purpose tools, each of which implements its own specialized analyses and optimized representation. This restricts the availability of the analyses, and also limits the reusability of the representation by other tools. Unintegrated tools also produce inconsistent views, which reduce the value of multiple views. This article describes a set of …


Design And Analysis Of A Class-Aware Recursive Loop Scheduler For Class-Based Scheduling, Raphael Rom, Moshe Sidi, Hwee-Pink Tan Oct 2006

Design And Analysis Of A Class-Aware Recursive Loop Scheduler For Class-Based Scheduling, Raphael Rom, Moshe Sidi, Hwee-Pink Tan

Research Collection School Of Computing and Information Systems

In this paper, we consider the problem of devising a loop scheduler that allocates slots to users according to their relative weights as smoothly as possible. Instead of the existing notion of smoothness based on balancedness, we propose a variance-based metric which is more intuitive and easier to compute.

We propose a recursive loop scheduler for a class-based scheduling scenario based on an optimal weighted round-robin scheduler. We show that it achieves very good allocation smoothness with almost no degradation in intra-class fairness. In addition, we also demonstrate the equivalence between our proposed metric and the balancedness-based metric.


India’S Rise As A Software Power: Governmental Policy Factors, Tad Drozdowski, Hai Huynh, Brian Lininger, Yicheng Peng, Naruedom Sakulyong Oct 2006

India’S Rise As A Software Power: Governmental Policy Factors, Tad Drozdowski, Hai Huynh, Brian Lininger, Yicheng Peng, Naruedom Sakulyong

Engineering and Technology Management Student Projects

The Indian government’s policies toward an open, global market, support of educational institutions, and enhancement of appropriate infrastructure helped enable their software industry to become critical components of India’s economic growth in the 1990s. The Technical, Organizational, and Personal perspective (T, O, and P) model is utilized to examine different affects that each perspective, inclusive of government policies, has on a socio-technical system (Software development in India). The Indian government has provided substantial economic liberalization to support their software industries, though continued reform is necessary to ensure that they remain a software superpower.


A Multi-Agent Framework For Testing Distributed Systems, Hany Elyamany, Miriam Capretz, Luiz Fernando Capretz Sep 2006

A Multi-Agent Framework For Testing Distributed Systems, Hany Elyamany, Miriam Capretz, Luiz Fernando Capretz

Electrical and Computer Engineering Publications

Software testing is a very expensive and time consuming process. It can account for up to 50% of the total cost of the software development. Distributed systems make software testing a daunting task. The research described in this paper investigates a novel multi-agent framework for testing 3-tier distributed systems. This paper describes the framework architecture as well as the communication mechanism among agents in the architecture. Web-based application is examined as a case study to validate the proposed framework. The framework is considered as a step forward to automate testing for distributed systems in order to enhance their reliability within …


Minimum Latency Broadcasting In Multi-Radio Multi-Channel Multi-Rate Wireless Meshes, Junaid Qadir, Archan Misra, Chun Tung Chou Sep 2006

Minimum Latency Broadcasting In Multi-Radio Multi-Channel Multi-Rate Wireless Meshes, Junaid Qadir, Archan Misra, Chun Tung Chou

Research Collection School Of Computing and Information Systems

We address the problem of minimizing the worst-case broadcast delay in multi-radio multi-channel multi-rate (MR2-MC) wireless mesh networks (WMN). The problem of 'efficient' broadcast in such networks is especially challenging due to the numerous interrelated decisions that have to be made. The multi-rate transmission capability of WMN nodes, interference between wireless transmissions, and the hardness of optimal channel assignment adds complexity to our considered problem. We present four heuristic algorithms to solve the minimum latency broadcast problem for such settings and show that the 'best' performing algorithms usually adapt themselves to the available radio interfaces and channels. We also study …


Pre-Conference Proceedings Of The Focus Symposium On Advances In Intelligent Software Systems, Collaborative Agent Design Research Center Aug 2006

Pre-Conference Proceedings Of The Focus Symposium On Advances In Intelligent Software Systems, Collaborative Agent Design Research Center

Collaborative Agent Design (CAD) Research Center

A very powerful new type of information systems technology is rapidly emerging, driven by government and commercial needs for expert decision-support and knowledge management. One very apparent result of this technology is increasingly intelligent software systems. Computer programs with collaborative agents that are capable of automatically reasoning about data and the dynamic changes in data that occur in real world decision-making situations are already in use by the military and are now transitioning to the commercial world.


Tabu Search For Optimization Of Military Supply Distribution, Ben Weber, Brett Bojduj, Jens G. Pohl Aug 2006

Tabu Search For Optimization Of Military Supply Distribution, Ben Weber, Brett Bojduj, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

The dynamic and non-hierarchical nature of the military domain presents a challenge for traditional supply chain optimization. Flow networks and simulation techniques have been applied to the military distribution problem, but are unable to provide time-definite delivery to customers. Recently, optimization approaches have been independently applied towards strategic and operational levels of planning. However, decomposing military distribution into separate problems forces optimization techniques to utilize imprecise data. The size of the military distribution problem has prevented optimization techniques from providing end-to-end planning capabilities. This paper presents a Tabu Search algorithm for simultaneously solving strategic and operational levels of planning. The …


Transway®: Planning With The Tabu Search Algorithm, Joshua Nibecker, Dennis Taylor, Robert Chambers, Harmony Larsen, Ken Cudworth, Clay Warren, Mark Porczak, Jens G. Pohl Aug 2006

Transway®: Planning With The Tabu Search Algorithm, Joshua Nibecker, Dennis Taylor, Robert Chambers, Harmony Larsen, Ken Cudworth, Clay Warren, Mark Porczak, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

Military deployment and distribution responsibilities call for intelligent collaborative tools in support of strategic and operational planning functions involving the sustainment and movement of military forces. The sustainment requirement is generated at the operational level and is dynamic. It is composed of shifting priorities responding to changes in commander’s intent and changes in the operational situation.

The TRANSWAY software application is designed as a set of intelligent collaborative tools supporting operators performing planning and re-planning tasks in a dynamically changing decision-making environment. TRANSWAY includes several agents with strategic and operational planning and re-planning capabilities. The principal agent is based on …


Elements Of Human Decision-Making, Jens G. Pohl Aug 2006

Elements Of Human Decision-Making, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

The purpose of this paper is to present some understandings of the human problem-solving activity that we have gained in the Collaborative Agent Design Research Center (CADRC) over the past two decades. Since we feel strongly that the human decision-maker should be an integral component of any computer-based decision-support system, it follows that we would have endeavored to incorporate many of the elements that appear to be important to the user in the design of these systems. The complexity of the human cognitive system is evidenced by the large body of literature that describes problem-solving behavior and the relatively fewer …


Social Network Dynamics For Open Source Software Projects, Y. Long, Keng Siau Aug 2006

Social Network Dynamics For Open Source Software Projects, Y. Long, Keng Siau

Research Collection School Of Computing and Information Systems

Drawing on social network theories and previous studies, this research is an initial effort to explore the dynamics of the social network structure in Open Source Software (OSS) teams. Three projects were selected from SourceForge.net in term of their similarities as well as their differences. Monthly data were extracted from the bug tracking system in order to achieve a longitudinal view of the interaction pattern of each project. Social network analysis was used to generate the indices of network structure. The finding suggests that the interaction pattern of OSS projects evolves from a single hub at the beginning to a …


Generalized On-Demand Service Architecture For Interactive Applications [Us 2006/0168107 A1], Rajesh K. Balan, Paul C. Castro, Maria R. Ebling, Archan Misra Jul 2006

Generalized On-Demand Service Architecture For Interactive Applications [Us 2006/0168107 A1], Rajesh K. Balan, Paul C. Castro, Maria R. Ebling, Archan Misra

Research Collection School Of Computing and Information Systems

A method, system, and computer program for executing a network-based distributed application. An infrastructure is described that includes application containers configured to execute an application instance of the distributed application and measure quality of service metrics for the application instance. Workload management elements form a decentralized workload management layer. The workload management layer is configured to assign a workload to application containers based on the quality of service metrics received by the application containers.


Student Interactive Campus Map At Marshall University, Edward Aractingi, Jamie Wolfe Jun 2006

Student Interactive Campus Map At Marshall University, Edward Aractingi, Jamie Wolfe

IT Research

Marshall University is a state-funded university in Huntington, West Virginia. Like many universities, it is a large organization with multiple and diverse units (colleges, departments, centers, etc.) and depends on data to run efficiently. Much of this data is used by multiple entities. To better manage the needed data collected by the university, the Marshall University Geographic Information System (MUGIS) has been developed. MUGIS will address several needs of Marshall University’s principal stakeholders. Stakeholders include the university administration, faculty, and students. One of the first applications developed for MUGIS was an interactive campus map. This Web-based application is intended to …


Afit Uav Swarm Mission Planning And Simulation System, James N. Slear Jun 2006

Afit Uav Swarm Mission Planning And Simulation System, James N. Slear

Theses and Dissertations

The purpose of this research is to design and implement a comprehensive mission planning system for swarms of autonomous aerial vehicles. The system integrates several problem domains including path planning, vehicle routing, and swarm behavior. The developed system consists of a parallel, multi-objective evolutionary algorithm-based path planner, a genetic algorithm-based vehicle router, and a parallel UAV swarm simulator. Each of the system's three primary components are developed on AFIT's Beowulf parallel computer clusters. Novel aspects of this research include: integrating terrain following technology into a swarm model as a means of detection avoidance, combining practical problems of path planning and …


Osprey: A Practical Type System For Validating Dimensional Unit Correctness Of C Programs, Lingxiao Jiang, Zhendong Su May 2006

Osprey: A Practical Type System For Validating Dimensional Unit Correctness Of C Programs, Lingxiao Jiang, Zhendong Su

Research Collection School Of Computing and Information Systems

Misuse of measurement units is a common source of errors in scientific applications, but standard type systems do not prevent such errors. Dimensional analysis in physics can be used to manually detect such errors in physical equations. It is, however, not feasible to perform such manual analysis for programs computing physical equations because of code complexity. In this paper, we present a type system to automatically detect potential errors involving measurement units. It is constraint-based: we model units as types and flow of units as constraints. However, standard type checking algorithms are not powerful enough to handle units because of …


Efficient Querying And Resource Management Using Distributed Presence Information In Converged Networks, Dipanjan Chakraborty, Koustuv Dasgupta, Archan Misra May 2006

Efficient Querying And Resource Management Using Distributed Presence Information In Converged Networks, Dipanjan Chakraborty, Koustuv Dasgupta, Archan Misra

Research Collection School Of Computing and Information Systems

Next-generation converged networks shall deliver many innovative services over the standardized SIPbased IMS signaling infrastructure. Several such services exploit the joint presence information of a consumer, i.e. SIP entity requesting a service, and a vendor, i.e. SIP resource providing a service. Presence information is a collection of contextual attributes (e.g. location, availability, reputation), some of which change dynamically. Moreover, this collective presence information is distributed across multiple presence servers. While performing query matching based on joint presence information, a server usually routes each query to a locally available resource. However, skews in the spatio-temporal distribution of queries and resources may …