Computer Science Faculty Research and Publications

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  • ItemOpen Access
    Work in progress: Data explorer - Assessment data integration, analytics, and visualization for STEM education research
    (2016-06-26) Weese, Joshua L.; Hsu, William H.; bhsu; Hsu, William; Weese, Joshua L.
    We describe a comprehensive system for comparative evaluation of uploaded and preprocessed data in physics education research with applicability to standardized assessments for discipline-based education research, especially in science, technology, mathematics, and engineering. Views are provided for inspection of aggregate statistics about student scores, comparison over time within one course, or comparison across multiple years. The design of this system includes a search facility for retrieving anonymized data from classes similar to the uploader's own. These visualizations include tracking of student performance on a range of standardized assessments. These assessments can be viewed as pre- and post-tests with comparative statistics (e.g., normalized gain), decomposed by answer in the case of multiple-choice questions, and manipulated using pre-specified data transformations such as aggregation and refinement (drill down and roll up). Furthermore, the system is designed to incorporate a scalable framework for machine learning-based analytics, including clustering and similarity-based retrieval, time series prediction, and probabilistic reasoning. © American Society for Engineering Education, 2016.
  • ItemOpen Access
    The impact of STEM experiences on student self-efficacy in computational thinking
    (2016-06-26) Weese, Joshua L.; Feldhausen, Russell; Bean, Nathan H.; russfeld; Feldhausen, Russell; Weese, Joshua L.; Bean, Nathan H.
    Since the introduction of new curriculum standards at K-12 schools, computational thinking has become a major research area. Creating and delivering content to enhance these skills, as well as evaluation, remain open problems. This paper describes two different interventions based on the Scratch programming language which aim to improve student self-efficacy in computer science and computational thinking. The two interventions were applied at a STEM outreach program for 5th-9th grade students. Previous experience in STEM related activities and subjects, as well as student self-efficacy, were collected using a developed pre- and post-survey. We discuss the impact of our intervention on student performance and confidence, and evaluate the validity of our instrument. © American Society for Engineering Education, 2016.
  • ItemOpen Access
    Developing and Piloting a Quantitative Assessment Tool for Cybersecurity Courses
    (American Society for Engineering Education, 2015-06-14) Vasserman, Eugene Y; Bell, Richard Scott; Sayre, Eleanor C; eyv
    The rapid growth of the Internet over the past two decades has led to a proliferation of network-capable computing devices. This growth has occurred so rapidly that the academic pipeline is struggling to keep up with the demand for cybersecurity professionals capable of protecting the expanding infrastructure. Training a security-focused workforce has become a critical objective of government entities, businesses, and academic institutions. As educators respond to this growing demand, developing new curriculum and methodologies for training cybersecurity professionals, there has been little systematic effort to assess student outcomes from the variety of pedagogical approaches being used. This paper presents the second stage in our work to develop an assessment tool designed to measure student interest and self-efficacy in relation to cybersecurity. Such a tool will allow educators to detect changes in student outcomes and thus systematically improve pedagogical methods. Initial instrument development is based on a qualitative study of students enrolled in an introductory cybersecurity course. We piloted the survey during the Spring and Fall 2014 semesters, and present the results here along with discussions of our ongoing and future activities with this project.
  • ItemOpen Access
    Improved Group Off-the-Record Messaging
    (Association for Computing Machinery (ACM), 2013-11-04) Liu, Hong; Vasserman, Eugene Y.; Hopper, Nicholas; eyv
    Off-the-Record Messaging (OTR) is an online analogy of face-to-face private chat { messages are confidential and au- thenticated at the time of the conversation, but cannot later be used to prove authorship. The original OTR protocol is limited to two parties, and is extended by multi-party OTR (mpOTR) to the group chat setting. In doing this, mpOTR unintentionally weakens the security properties provided by its two-party predecessor. We propose an improved group OTR (GOTR) protocol that provides unconditional repudi- ability, and show how to obtain data origin authentication given this level of repudiability. GOTR resists network failure, colluding and independent malicious insiders, and provides efficient and exible mem- bership management. We analyze the security properties and performance of GOTR, and present measurement re- sults of a proof-of-concept implementation of GOTR.
  • ItemOpen Access
    Security and Interoperable Medical Device Systems, Part 2: Failures, Consequences and Classifications
    (IEEE Computer Society; Institute of Electrical and Electronics Engineers, 2013-10-13) Vasserman, Eugene Y.; Venkatasubramanian, Krishna K.; Sokolsky, Oleg; Lee, Insup; eyv
    Interoperable medical devices (IMDs) face threats due to the increased attack surface presented by interoperability and the corresponding infrastructure. Introducing networking and coordination functionalities fundamentally alters medical systems' security properties. Understanding the threats is an important first step in eventually designing security solutions for such systems. Part 2 of this two-part article defines a failure model, or the specific ways in which IMD environments might fail when attacked. An attack-consequences model expresses the combination of failures experienced by IMD environments for each attack vector. This analysis leads to interesting conclusions about regulatory classes of medical devices in IMD environments subject to attacks. Part 1 can be found here:
  • ItemOpen Access
    Security and Interoperable Medical Device Systems: Part 1
    (IEEE Computer Society; Institute of Electrical and Electronics Engineers, 2013-10-16) Venkatasubramanian, Krishna K.; Vasserman, Eugene Y.; Sokolsky, Oleg; Lee, Insup; eyv
    Interoperable medical devices (IMDs) face threats due to the increased attack surface presented by interoperability and the corresponding infrastructure. Introducing networking and coordination functionalities fundamentally alters medical systems' security properties. Understanding the threats is an important first step in eventually designing security solutions for such systems. Part 1 of this two-part article provides an overview of the IMD environment and the attacks that can be mounted on it.
  • ItemOpen Access
    On the Effectiveness of k-Anonymity Against Traffic Analysis and Surveillance
    (2006-10-30) Hopper, Nicholas; Vasserman, Eugene Y.; eyv
    The goal of most research on anonymity, including all currently used systems for anonymity, is to achieve anonymity through unlinkability: an adversary should not be able to determine the correspondence between the input and output messages of the system. An alternative anonymity goal is unobservability: an adversary should not be able to determine who sends and who receives messages. We study the effect of k-anonymity, a weak form of unobservability, on two types of attacks against systems that provide only unlinkability.
  • ItemOpen Access
    Foundational Security Principles for Medical Application Platforms* (Extended Abstract)
    (2015-01-15) Vasserman, Eugene Y.; Hatcliff, John; eyv
    We describe a preliminary set of security requirements for safe and secure next-generation medical systems, consisting of dynamically composable units, tied together through a real-time safety-critical middleware. We note that this requirement set is not the same for individual (stand-alone) devices or for electronic health record systems, and we must take care to define system-level requirements rather than security goals for components. The requirements themselves build on each other such that it is difficult or impossible to eliminate any one of the requirements and still achieve high-level security goals.
  • ItemOpen Access
    A distributed data component for the Open Modeling Interface
    (2014-03-27) Bulatewicz, Tom; Andresen, Daniel A.; Auvenshine, S.; Peterson, Jeffrey M.; Steward, David R.; tombz; dan; jpeters; steward
    As the volume of collected data continues to increase in the environmental sciences, so too does the need for effective means for accessing those data. We have developed an Open Modeling Interface (OpenMI) data component that retrieves input data for model components from environmental information systems and delivers output data to those systems. The adoption of standards for both model component input–output interfaces and web services make it possible for the component to be reconfigured for use with different linked models and various online systems. The data component employs three techniques tailored to the unique design of the OpenMI that enable efficient operation: caching, prefetching, and buffering, making it capable of scaling to large numbers of simultaneous simulations executing on a computational grid. We present the design of the component, an evaluation of its performance, and a case study demonstrating how it can be incorporated into modeling studies.
  • ItemOpen Access
    Secure encounter-based mobile social networks: requirements, designs, and trade-offs
    (2013-03-21) Mohaisen, Abedelaziz; Kune, Denis Foo; Vasserman, Eugene Y.; Kim, Myungsun; Kim, Yongdae; eyv
    Encounter-based social networks and encounter-based systems link users who share a location at the same time, as opposed to the traditional social network paradigm of linking users who have an offline friendship. This new approach presents challenges that are fundamentally different from those tackled by previous social network designs. In this paper, we explore the functional and security requirements for these new systems, such as availability, security, and privacy, and present several design options for building secure encounter-based social networks. To highlight these challenges we examine one recently proposed encounter-based social network design and compare it to a set of idealized security and functionality requirements. We show that it is vulnerable to several attacks, including impersonation, collusion, and privacy breaching, even though it was designed specifically for security. Mindful of the possible pitfalls, we construct a flexible framework for secure encounter-based social networks, which can be used to construct networks that offer different security, privacy, and availability guarantees. We describe two example constructions derived from this framework, and consider each in terms of the ideal requirements. Some of our new designs fulfill more requirements in terms of system security, reliability, and privacy than previous work. We also evaluate real-world performance of one of our designs by implementing a proof-of-concept iPhone application called MeetUp. Experiments highlight the potential of our system and hint at the deployability of our designs on a large scale.
  • ItemOpen Access
    (Information Science Reference, 2013-11-15) McHaney, Roger W.; Spire, Lynda D.; Boggs, Rosemary B.; mchaney; lspire; rboggs; Hai-Jew, Shalin
    A team at Kansas State University recently launched the E-Learning Faculty Modules wiki to enhance and support online faculty development. This project is customized for teaching in the Kansas State University distance-learning program but contains a broad set of information that might be useful to others. This site is constructed using wiki technology, which permits access, multimedia expressiveness, remote collaboration, tracking, and reversibility of postings. Other tools on the site are derived from MediaWiki and its open-source capabilities. The wiki includes an overall ontology, templates, categories, completed and seeded entries, input boxes, and menus that ensure users can easily use and join the community. Taken holistically, these attributes create an ideal venue for sharing ideas and encouraging synergistic improvement of teaching practices. This chapter describes the implementation process of and gives insight into its purpose, features, and uses.
  • ItemOpen Access
    Efficient data collection from Open Modeling Interface (OpenMI) components
    (CSREA Press, 2013-01-10) Bulatewicz, Tom; Andresen, Daniel; tombz; dan; Arabnia, Hamid R.; Ishii, Hiroshi; Ito, Minoru; Joe, Kazuki; Nishikawa, Hiroaki
    The management of output data from simulation models can be simplified in grid environments by automating and standardizing the way in which they are collected and stored. In the context of component-based computer models with well-defined input-output interfaces, generalpurpose data collector components can be linked to model components to retrieve output data and deliver them to online repositories via web services. We have developed a distributed data collector component that adheres to the Open Modeling Interface (OpenMI). The component buffers data to minimize the impact on a simulation’s runtime and shares the buffer across compute nodes for load-balancing and cooperative delivery of data to web services. The buffering capability resulted in minimal runtimes within a single simulation and reduced data delivery latencies for concurrently executing simulations across a cluster. In this paper we report on the design and performance of the component.
  • ItemOpen Access
    Efficient and formal generalized symbolic execution
    (2011-06-09) Deng, Xianghua; Lee, Jooyong; Robby; robby
    Programs that manipulate dynamic heap objects are difficult to analyze due to issues like aliasing. Lazy initialization algorithm enables the classical symbolic execution to handle such programs. Despite its successes, there are two unresolved issues: (1) inefficiency; (2) lack of formal study. For the inefficiency issue, we have proposed two improved algorithms that give significant analysis time reduction over the original lazy initialization algorithm. In this article, we formalize the lazy initialization algorithm and the improved algorithms as operational semantics of a core subset of the Java Virtual Machine (JVM) instructions, and prove that all algorithms are relatively sound and complete with respect to the JVM concrete semantics. Finally, we conduct a set of extensive experiments that compare the three algorithms and demonstrate the efficiency of the improved algorithms.
  • ItemOpen Access
    Efficient data access for Open Modeling Interface (OpenMI)components
    (2011-07-18) Bulatewicz, Tom; Andresen, Daniel; tombz; dan
    Data management for linked (or coupled) simulation models can be a challenging task when deploying to grid environments. In cases where the linked models conform to a standard interface for data input and output, generalpurpose data providers can be used to supply data to the models from online sources, reducing the complexity of the deployment. We have developed a data provider component that conforms to the Open Modeling Interface (OpenMI) that is suitable for use on computational grids. Through the application of three techniques, caching, prefetching, and pipelining, the component efficiently retrieves data from standards-based web services and delivers the data to OpenMI-compliant models. Each technique resulted in varying performance improvements both within a single simulation and across multiple simulations concurrently executing on a cluster. In this paper we report on the design of the component and the evaluation of its performance.
  • ItemOpen Access
    Efficient data access for Open Modeling Interface (OpenMI) components
    (2011-11-17) Bulatewicz, Tom; Andresen, Daniel; tombz; dan
    Data management can be a challenging task when employing linked (or coupled) simulation models that execute independently and cooperate to collectively carry out a simulation. In the case of models that are software components with well-defined input/output interfaces, data access can be simplified by linking general-purpose data components to model components. An interdisciplinary team of engineers and scientists at Kansas State University are integrating crop, hydrological, and economic models toward developing a comprehensive understanding of agricultural systems (NSF grant GEO0909515). These multidisciplinary models are linked together using the Open Modeling Interface (OpenMI) which defines a standard way for software components to exchange data with each other and coordinate their execution. In this work we present the design of a general-purpose Data Provider Component (DPC) that is capable of delivering data from online sources to OpenMI components.
  • ItemOpen Access
    Calibration of a crop model to irrigated water use using a genetic algorithm
    (2009-08-14) Bulatewicz, Tom; Jin, W.; Staggenborg, Scott A.; Lauwo, S.; Miller, M.; Das, Sanjoy; Andresen, D.; Peterson, Jeffrey M.; Steward, David R.; Welch, Stephen M.; tombz; jpeters; sstaggen; welchsm; steward; sdas
    Near-term consumption of groundwater for irrigated agriculture in the High Plains Aquifer supports a dynamic bio-socio-economic system, all parts of which will be impacted by a future transition to sustainable usage that matches natural recharge rates. Plants are the foundation of this system and so generic plant models suitable for coupling to representations of other component processes (hydrologic, economic, etc.) are key elements of needed stakeholder decision support systems. This study explores utilization of the Environmental Policy Integrated Climate (EPIC) model to serve in this role. Calibration required many facilities of a fully deployed decision support system: geo-referenced databases of crop (corn, sorghum, alfalfa, and soybean), soil, weather, and water-use data (4931 well-years), interfacing heterogeneous software components, and massively parallel processing (3.8×109 model runs). Bootstrap probability distributions for ten model parameters were obtained for each crop by entropy maximization via the genetic algorithm. The relative errors in yield and water estimates based on the parameters are analyzed by crop, the level of aggregation (county- or well-level), and the degree of independence between the data set used for estimation and the data being predicted.
  • ItemOpen Access
    Accessible integration of agriculture, groundwater, and economic models using the Open Modeling Interface (OpenMI): methodology and initial results
    (2010-03-16) Bulatewicz, Tom; Yang, X.; Peterson, Jeffrey M.; Staggenborg, Scott A.; Welch, Stephen M.; Steward, David R.; tombz; jpeters; sstaggen; welchsm; steward
    Policy for water resources impacts not only hydrological processes, but the closely intertwined economic and social processes dependent on them. Understanding these process interactions across domains is an important step in establishing effective and sustainable policy. Multidisciplinary integrated models can provide insight to inform this understanding, though the extent of software development necessary is often prohibitive, particularly for small teams of researchers. Thus there is a need for practical methods for building interdisciplinary integrated models that do not incur a substantial development effort. In this work we adopt the strategy of linking individual domain models together to build a multidisciplinary integrated model. The software development effort is minimized through the reuse of existing models and existing model-linking tools without requiring any changes to the model source codes, and linking these components through the use of the Open Modeling Interface (OpenMI). This was found to be an effective approach to building an agricultural-groundwater-economic integrated model for studying the effects of water policy in irrigated agricultural systems. The construction of the integrated model provided a means to evaluate the impacts of two alternative water-use policies aimed at reducing irrigated water use to sustainable levels in the semi-arid grasslands overlying the Ogallala Aquifer of the Central US. The results show how both the economic impact in terms of yield and revenue and the environmental impact in terms of groundwater level vary spatially throughout the study region for each policy. Accessible integration strategies are necessary if the practice of interdisciplinary integrated simulation is to become widely adopted.