Computer Sciences Commons^™

An Empirical Study Of Fault Localization For End-User Programmers, Joseph R. Ruthruff, Margaret Burnett, Gregg Rothermel

CSE Conference and Workshop Papers

End users develop more software than any other group of programmers, using software authoring devices such as e-mail filtering editors, by-demonstration macro builders, and spreadsheet environments. Despite this, there has been little research on finding ways to help these programmers with the dependability of their software. We have been addressing this problem in several ways, one of which includes supporting end-user debugging activities through fault localization techniques. This paper presents the results of an empirical study conducted in an end-user programming environment to examine the impact of two separate factors in fault localization techniques that affect technique effectiveness. Our results …

Performance Analysis Of Sparse Traffic Grooming In Wdm Mesh Networks, Wang Yao, Mengke Li, Byrav Ramamurthy

CSE Conference and Workshop Papers

Sparse traffic grooming is a practical problem to be addressed in heterogeneous multi-vendor optical WDM networks where only some of the optical cross-connects (OXCs) have grooming capabilities. Such a network is called as a sparse grooming network. The sparse grooming problem under dynamic traffic in optical WDM mesh networks is a relatively unexplored problem. In this work, we propose the maximize-lightpath-sharing multi-hop (MLS-MH) grooming algorithm to support dynamic traffic grooming in sparse grooming networks. We also present an analytical model to evaluate the blocking performance of the MLS-MH algorithm. Simulation results show that MLSMH outperforms an existing grooming algorithm, the …

A Controlled Experiment Assessing Test Case Prioritization Techniques Via Mutation Faults, Hyunsook Do, Gregg Rothermel

CSE Conference and Workshop Papers

Regression testing is an important part of software maintenance, but it can also be very expensive. To reduce this expense, software testers may prioritize their test cases so that those that are more important are run earlier in the regression testing process. Previous work has shown that prioritization can improve a test suite’s rate of fault detection, but the assessment of prioritization techniques has been limited to hand-seeded faults, primarily due to the belief that such faults are more realistic than automatically generated (mutation) faults. A recent empirical study, however, suggests that mutation faults can be representative of real faults. …

Efficient Test Compaction For Pseudo-Random Testing, Sheng Zhang, Sharad C. Seth, Bhargab B. Bhattacharya

CSE Conference and Workshop Papers

Compact set of 3-valued test vectors for random pattern resistant faults are covered in multiple test passes. During a pass, its associated test cube specifies certain bits in the scan chain to be held fixed and others to change pseudo-randomly. We propose an algorithm to find a small number of cubes to cover all the test vectors, thus minimizing total test length. The test-cube finding algorithm repeatedly evaluates small perturbations of the current solution so as to maximize the expected test coverage of the cube. Experimental results show that our algorithm covers the test vectors by test cubes that are …

Neighborhood Interchangeability And Dynamic Bundling For Non-Binary Finite Csps, Anagh Lal, Berthe Y. Choueiry, Eugene C. Freuder

CSE Conference and Workshop Papers

Neighborhood Interchangeability (NI) identifies the equivalent values in the domain of a variable of a Constraint Satisfaction Problem (CSP) by considering only the constraints that directly apply to the variable. Freuder described an algorithm for efficiently computing NI values in binary CSPs. In this paper, we show that the generalization of this algorithm to non-binary CSPs is not straightforward, and introduce an efficient algorithm for computing NI values in the presence of non-binary constraints. Further, we show how to interleave this mechanism with search for solving CSPs, thus yielding a dynamic bundling strategy. While the goal of dynamic bundling is …

Crtdh: An Efficient Key Agreement Scheme For Secure Group Communications In Wireless Ad Hoc Networks, Ravi K Balachandran, Byrav Ramamurthy, Xukai Zou, N.V. Vinodchandran

CSE Conference and Workshop Papers

As a result of the growing popularity of wireless networks, in particular ad hoc networks, security over such networks has become very important. In this paper, we study the problem of secure group communications (SGC) and key management over ad hoc networks. We identify the key features of any SGC protocol for such networks. We also propose an efficient key agreement scheme for SGC. The scheme solves two important problems that exist in most current SGC schemes: requirement of member serialization and existence of a central entity. Besides this, the protocol also has many highly desirable properties such as contributory …

Ground Water Monitoring Using Smart Sensors, Srikanth Anumalla, Byrav Ramamurthy, David Gosselin

CSE Conference and Workshop Papers

Groundwater resources are the principal source of drinking water for about 50 percent of the United States population. Groundwater resources in Nebraska are under increasing stress as there is a rapid growth in their usage. Water managers need more timely and accurate data to assess ground-water conditions to manage adverse situations such as drought and loss of pumpage in agriculture and domestic water supply. Currently groundwater researchers use stand-alone data logging equipment which is labor intensive and the method is not easily scalable if the number of logging locations increases. Commercially available real-time data monitoring solutions are either prohibitively costly …

Survivable Waveband Switching In Wdm Mesh Networks Under Dedicated Path-Protection, Mengke Li, Byrav Ramamurthy

CSE Conference and Workshop Papers

This paper considers the problem of dedicated path-protection in wavelength-division multiplexed (WDM) mesh networks with waveband switching functionality under shared risk link group (SRLG) constraints. Two dedicated path protection schemes are proposed, namely the PBABL scheme and the MPABWL scheme. The PBABL scheme protects each working waveband-path through a backup waveband-path. The MPABWL scheme protects each working waveband-path by either a backup waveband-path or multiple backup lightpaths. Heuristic algorithms adopting random optimization technique are proposed for both the schemes. The performance of the two protection schemes is studied and compared. Simulation results show that both the heuristics can obtain optimum …

Same-Destination-Intermediate Grouping Vs. End-To-End Grouping For Waveband Switching In Wdm Mesh Networks, Mengke Li, Wang Yao, Byrav Ramamurthy

CSE Conference and Workshop Papers

We investigate waveband switching (WBS) with different grouping strategies in wavelength-division multiplexing (WDM) mesh networks. End-to-end waveband switching (ETEWBS) and same-destination-intermediate waveband switching (SD-IT-WBS) are analyzed and compared in terms of blocking probability and cost savings. First, an analytical model for ETEWBS is proposed to determine the network blocking probability in a mesh network. For SD-IT-WBS, a simple waveband switching algorithm is presented. An analytical model to determine the network blocking probability is proposed for SD-IT-WBS based on the algorithm. The analytical results are validated by comparing with simulation results. Both results match well and show that ETE-WBS slightly outperforms …

A Novel Cost-Efficient On-Line Intermediate Waveband-Switching Scheme In Wdm Mesh Networks, Mengke Li, Wang Yao, Byrav Ramamurthy

CSE Conference and Workshop Papers

Waveband switching (WBS) is an important technique to save switching and transmission cost in wavelength -division multiplexed (WDM) optical networks. A cost-efficient WBS scheme would enable network carriers to increase the network throughput (revenue) while achieving significant cost savings. We identify the critical factors that determine the WBS network throughput and switching cost and propose a novel intermediate waveband switching (IT-WBS) algorithm, called the minimizing-weighted-cost (MWC) algorithm. The MWC algorithm defines a cost for each candidate route of a call. By selecting the route with the smallest weighted cost, MWC balances between minimizing the call blocking probability and minimizing the …

Discontinuous Waveband Switching In Wdm Optical Networks, Bhavana Lekkala, Byrav Ramamurthy

CSE Conference and Workshop Papers

Routing techniques used in wavelength routed optical networks (WRN) do not give an efficient solution with Waveband routed optical networks (WBN) as the objective of routing in WRN is to reduce the blocking probability and that in WBN is to reduce the number of switching ports. Routing in WBN can be divided two parts, finding the route and grouping the wavelength assigned into that route with some existing wavelengths/wavebands. In this paper, we propose a heuristic for waveband routing, which uses a new grouping strategy called discontinuous waveband grouping to group the wavelengths into a waveband. The main objective of …

On Finding Consecutive Test Vectors In A Random Sequence For Energy-Aware Bist Design, Sheng Zhang, Sharad C. Seth, Bhargab B. Bhattacharya

CSE Conference and Workshop Papers

During pseudorandom testing, a significant amount of energy and test application time is wasted for generating and for applying “useless” test vectors that do not contribute to fault dropping. For low-power testing, modification logic/ROM may be used to skip the LFSR states that generate useless test patterns. The overhead of extra logic increases rapidly with the number of such jumps. Since identification of useless patterns strongly depends on the order in which incremental fault simulation is performed, an elegant solution to this problem would be to find a minimum set of segments in the LFSR sequence, where each segment corresponds …

Exploiting The Advantages Of Object-Based Dsm In A Heterogeneous Cluster Environment, Xuli Liu, Hong Jiang, Leen-Kiat Soh

CSE Conference and Workshop Papers

In recent years, increasing effort has been made by the cluster and grid computing community to build object- based Distributed Shared Memory systems (DSM) in a cluster environment. In most of these systems, a shared object is simply used as a data-exchanging unit so as to alleviate the false-sharing problem, and the advantages of sharing objects remain to be fully exploited. Thus, this paper is motivated to investigate the potential advantages of object-based DSM. For example, the performance of a distributed application may be significantly improved by adaptively and judiciously setting the size of the shared objects, i.e., granularity. This …

Face Recognition Using Landmark-Based Bidimensional Regression, Jiazheng Shi, Ashok Samal, David Marx

CSE Conference and Workshop Papers

This paper studies how biologically meaningful landmarks extracted from face images can be exploited for face recognition using the bidimensional regression. Incorporating the correlation statistics of landmarks, this paper also proposes a new approach called eigenvalue weighted bidimensional regression. Complex principal component analysis is used for computing eigenvalues and removing correlation among landmarks. We evaluate our approach using two standard face databases: the Purdue AR and the NIST FERET. Experimental results show that the bidimensional regression is an efficient method to exploit geometry information of face images.

Dgkd: Distributed Group Key Distribution With Authentication Capability, Pratima Adusumilli, Xukai Zou, Byrav Ramamurthy

CSE Conference and Workshop Papers

Group key management (GKM} is the most important issue in secure group communication (SCC). The existing GKM protocols fall into three typical classes: centralized group key distribution (CGKD), decentralized group key management (DGKM), and distributed/contributory group key agreement (CGKA). Serious problems remains in these protocols, as they require existence of central trusted entities (such as group controller or subgroup controllers), relaying of messages (by subgroup controllers), or strict member synchronization (JOT multiple round stepwise key agreement), thus suffering from the single point of failure and attack, performance bottleneck, or mis-operations in the situation of transmission delay or network failure. In …

A Heuristic With Bounded Guarantee To Compute Diverse Paths Under Shared Protection In Wdm Mesh Networks, Ajay Todimala, Byrav Ramamurthy

CSE Conference and Workshop Papers

Establishing a fault-tolerant connection in a network involves computation of diverse working and protection paths. The Shared Risk Link Group (SRLG) [1] concept is used to model several types of failure conditions such as link, node, fiber conduit, etc. In this work we focus on the problem of computing optimal SRLG/link diverse paths under shared protection. Shared protection technique improves network resource utilization by allowing protection paths of multiple connections to share resources. In this work we propose an iterative heuristic for computing SRLG/link diverse paths. We present a method to calculate a quantitative measure that provides a bounded guarantee …

Least-Cost Disjoint Paths With Dependent Cost Structure In Wavelength Continuous Optical Wdm Networks, Ajay Todimala, Byrav Ramamurthy

CSE Conference and Workshop Papers

One of the important issues in establishing a fault tolerant connection in a wavelength division multiplexing optical network is computing a pair of disjoint working and protection paths and a free wavelength along the paths. While most of the earlier research focused only on computing disjoint paths, in this work we consider computing both disjoint paths and a free wavelength along the paths.

The concept of dependent cost structure (DCS) of protection paths to enhance their resource sharing ability was proposed in our earlier work. In this work we extend the concept of DCS of protection paths to wavelength continuous …

Helping End-Users “Engineer” Dependable Web Applications, Sebastian Elbaum, Kalyan-Ram Chilakamarri, Bhuvana Gopal, Gregg Rothermel

CSE Conference and Workshop Papers

End-user programmers are increasingly relying on web authoring environments to create web applications. Although often consisting primarily of web pages, such applications are increasingly going further, harnessing the content available on the web through “programs” that query other web applications for information to drive other tasks. Unfortunately, errors can be pervasive in web applications, impacting their dependability. This paper reports the results of an exploratory study of end-user web application developers, performed with the aim of exposing prevalent classes of errors. The results suggest that end-users struggle the most with the identification and manipulation of variables when structuring requests to …

Balancing Exploration And Exploitation: A New Algorithm For Active Machine Learning, Thomas Osugi, Deng Kun, Stephen Scott

CSE Conference and Workshop Papers

Active machine learning algorithms are used when large numbers of unlabeled examples are available and getting labels for them is costly (e.g. requiring consulting a human expert). Many conventional active learning algorithms focus on refining the decision boundary, at the expense of exploring new regions that the current hypothesis misclassifies. We propose a new active learning algorithm that balances such exploration with refining of the decision boundary by dynamically adjusting the probability to explore at each step. Our experimental results demonstrate improved performance on data sets that require extensive exploration while remaining competitive on data sets that do not. Our …

Neighborhood Interchangeability And Dynamic Bundling For Non-Binary Csps, Anagh Lal, Berthe Y. Choueiry, Eugene C. Freuder

CSE Conference and Workshop Papers

1. Interchangeability: An algorithm for computing interchangeability in non-binary CSPs.

2. Dynamic bundling: Integration of the above with backtrack search for solving non-binary CSPs.

3. Experiments demonstrating the benefits of dynamic bundling

·Finding multiple, robust solutions.

·Decreasing computational cost of search.