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Software Engineering

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Full-Text Articles in Physical Sciences and Mathematics

Decision-Making With Cross-Entropy For Self-Adaptation, Gabriel A. Moreno, Ofer Strichman, Sagar Chaki, Radislav Vaisman Apr 2017

Decision-Making With Cross-Entropy For Self-Adaptation, Gabriel A. Moreno, Ofer Strichman, Sagar Chaki, Radislav Vaisman

Gabriel A. Moreno

Approaches to decision-making in self-adaptive systems are increasingly becoming more effective at managing the target system by taking into account more elements of the decision problem that were previously ignored. These approaches have to solve complex optimization problems at run time, and even though they have been shown to be suitable for different kinds of systems, their time complexity can make them excessively slow for systems that have a large adaptation-relevant state space, or that require a tight control loop driven by fast decisions. In this paper we present an approach to speed up complex proactive latency-aware self-adaptation decisions, using …


Comparing Model-Based Predictive Approaches To Self-Adaptation: Cobra And Pla, Gabriel A. Moreno, Alessandro V. Papadopoulos, Konstantinos Angelopoulos, Javier Camara, Bradley Schmerl Apr 2017

Comparing Model-Based Predictive Approaches To Self-Adaptation: Cobra And Pla, Gabriel A. Moreno, Alessandro V. Papadopoulos, Konstantinos Angelopoulos, Javier Camara, Bradley Schmerl

Gabriel A. Moreno

Modern software-intensive systems must often guarantee certain quality requirements under changing run-time conditions and high levels of uncertainty. Self-adaptation has proven to be an effective way to engineer systems that can address such challenges, but many of these approaches are purely reactive and adapt only after a failure has taken place. To overcome some of the limitations of reactive approaches (e.g., lagging behind environment changes and favoring short-term improvements), recent proactive self-adaptation mechanisms apply ideas from control theory, such as model predictive control (MPC), to improve adaptation. When selecting which MPC approach to apply, the improvement that can be obtained …


Software Engineering For Science, Jeffrey C. Carver, Neil P. Chue Hong, George K. Thiruvathukal Jan 2017

Software Engineering For Science, Jeffrey C. Carver, Neil P. Chue Hong, George K. Thiruvathukal

George K. Thiruvathukal

Software Engineering for Science provides an in-depth collection of peer-reviewed chapters that describe experiences with applying software engineering practices to the development of scientific software. It provides a better understanding of how software engineering is and should be practiced, and which software engineering practices are effective for scientific software. The book starts with a detailed overview of the Scientific Software Lifecycle, and a general overview of the scientific software development process. It highlights key issues commonly arising during scientific software development, as well as solutions to these problems. The second part of the book provides examples of the use of …


Hybrid Planning For Decision Making In Self-Adaptive Systems, Ashutosh Pandey, Gabriel A. Moreno, Javier Camara, David Garlan Aug 2016

Hybrid Planning For Decision Making In Self-Adaptive Systems, Ashutosh Pandey, Gabriel A. Moreno, Javier Camara, David Garlan

Gabriel A. Moreno

Run-time generation of adaptation plans is a powerful mechanism that helps a self-adaptive system to meet its goals in a dynamically changing environment. In the past, researchers have demonstrated successful use of various automated planning techniques to generate adaptation plans at run time. However, for a planning technique, there is often a trade-off between timeliness and optimality of the solution. For some self-adaptive systems, ideally, one would like to have a planning approach that is both quick and finds an optimal adaptation plan. To find the right balance between these conflicting requirements, this paper introduces a hybrid planning approach that …


Efficient Decision-Making Under Uncertainty For Proactive Self-Adaptation, Gabriel A. Moreno, Javier Camara, David Garlan, Bradley Schmerl Jul 2016

Efficient Decision-Making Under Uncertainty For Proactive Self-Adaptation, Gabriel A. Moreno, Javier Camara, David Garlan, Bradley Schmerl

Gabriel A. Moreno

Proactive latency-aware adaptation is an approach for self-adaptive systems that improves over reactive adaptation by considering both the current and anticipated adaptation needs of the system, and taking into account the latency of adaptation tactics so that they can be started with the necessary lead time. Making an adaptation decision with these characteristics requires solving an optimization problem to select the adaptation path that maximizes an objective function over a finite look-ahead horizon. Since this is a problem of selecting adaptation actions in the context of the probabilistic behavior of the environment, Markov decision processes (MDP) are a suitable approach. …


Comparing The Fieldscout Greenindex+ Chlorophyll Sensing App To The Minolta Spad Meter, Jessica D. Pille, John E. Sawyer, Daniel W. Barker Jul 2016

Comparing The Fieldscout Greenindex+ Chlorophyll Sensing App To The Minolta Spad Meter, Jessica D. Pille, John E. Sawyer, Daniel W. Barker

John E. Sawyer

With the improvement of mobile computing, the company Spectrum Technologies, Inc. has developed a precision Ag App which adapts an iPod, iPad, or iPhone camera to select for specific wavelengths of light from a corn leaf (Zea mays L.) in comparison to accompanying board for light/color comparison. The App computes a Dark Green Color Index (DGCI), indicating leaf greenness, which relates to the amount of chlorophyll and thus, indirectly, leaf nitrogen (N) content. The question posed for this study is: How accurate and convenient is the App compared to a proven technology, the Minolta 502 Soil-Plant Analysis Development (SPAD) meter; …


User Interface Design, Moritz Stefaner, Sebastien Ferre, Saverio Perugini, Jonathan Koren, Yi Zhang Apr 2016

User Interface Design, Moritz Stefaner, Sebastien Ferre, Saverio Perugini, Jonathan Koren, Yi Zhang

Saverio Perugini

As detailed in Chap. 1, system implementations for dynamic taxonomies and faceted search allow a wide range of query possibilities on the data. Only when these are made accessible by appropriate user interfaces, the resulting applications can support a variety of search, browsing and analysis tasks. User interface design in this area is confronted with specific challenges. This chapter presents an overview of both established and novel principles and solutions.


Intelligent Systems Development In A Non Engineering Curriculum, Emily Brand, William Honig, Matthew Wojtowicz Feb 2016

Intelligent Systems Development In A Non Engineering Curriculum, Emily Brand, William Honig, Matthew Wojtowicz

William L Honig

Much of computer system development today is programming in the large - systems of millions of lines of code distributed across servers and the web. At the same time, microcontrollers have also become pervasive in everyday products, economical to manufacture, and represent a different level of learning about system development. Real world systems at this level require integrated development of custom hardware and software.

How can academic institutions give students a view of this other extreme - programming on small microcontrollers with specialized hardware? Full scale system development including custom hardware and software is expensive, beyond the range of any …


An Immersive Telepresence System Using Rgb-D Sensors And Head-Mounted Display, Xinzhong Lu, Ju Shen, Saverio Perugini, Jianjun Yang Jan 2016

An Immersive Telepresence System Using Rgb-D Sensors And Head-Mounted Display, Xinzhong Lu, Ju Shen, Saverio Perugini, Jianjun Yang

Saverio Perugini

We present a tele-immersive system that enables people to interact with each other in a virtual world using body gestures in addition to verbal communication. Beyond the obvious applications, including general online conversations and gaming, we hypothesize that our proposed system would be particularly beneficial to education by offering rich visual contents and interactivity. One distinct feature is the integration of egocentric pose recognition that allows participants to use their gestures to demonstrate and manipulate virtual objects simultaneously. This functionality enables the instructor to effectively and efficiently explain and illustrate complex concepts or sophisticated problems in an intuitive manner. The …


Your Location Has Been Shared 5,398 Times! A Field Study On Mobile App Privacy Nudging (Cmu-Isr-14-116), Hazim Almuhimedi, Florian Schaub, Norman Sadeh, Idris Adjerid, Alessandro Acquisti, Joshua Gluck, Lorrie Cranor, Yuvraj Agarwal Dec 2015

Your Location Has Been Shared 5,398 Times! A Field Study On Mobile App Privacy Nudging (Cmu-Isr-14-116), Hazim Almuhimedi, Florian Schaub, Norman Sadeh, Idris Adjerid, Alessandro Acquisti, Joshua Gluck, Lorrie Cranor, Yuvraj Agarwal

Lorrie F Cranor

Smartphone users are often unaware of the data collected by apps running on their devices. We report on a study that evaluates the benefits of giving users an app permission manager and of sending them nudges intended to raise their awareness of the data collected by their apps. Our study provides both qualitative and quantitative evidence that these approaches are complementary and can each play a significant role in empowering users to more effectively control their privacy. For instance, even after a week with access to the permission manager, participants benefited from nudges showing them how often some of their …


Augmenting Distance Education Skills Development In Paramedic Science Through Mixed Media Visualisation, Michael Cowling, Emma Moore, James Birt Jul 2015

Augmenting Distance Education Skills Development In Paramedic Science Through Mixed Media Visualisation, Michael Cowling, Emma Moore, James Birt

James Birt

Extract: This paper presents a learning intervention using mixed media visualisation (3D printing and Augmented Reality simulation) to enhance skills development for paramedic science students studying through distance education. Presented is a research methodology to evaluate the effectiveness of the mixed media visualisation techniques to provide more hands-on skill practice to paramedic science students studying the course at a distance. The context for this study is the skills acquisition and retention, focusing on Laryngoscopy with foreign body removal.


Contracts Made Manifest, Michael Greenberg, Benjamin C. Pierce, Stephanie Weirich Jun 2015

Contracts Made Manifest, Michael Greenberg, Benjamin C. Pierce, Stephanie Weirich

Stephanie Weirich

Since Findler and Felleisen (Findler, R. B. & Felleisen, M. 2002) introduced higher-order contracts, many variants have been proposed. Broadly, these fall into two groups: some follow Findler and Felleisen (2002) in using latent contracts, purely dynamic checks that are transparent to the type system; others use manifest contracts, where refinement types record the most recent check that has been applied to each value. These two approaches are commonly assumed to be equivalent—different ways of implementing the same idea, one retaining a simple type system, and the other providing more static information. Our goal is to formalize and clarify this …


Query Analyzer And Manager For Complex Event Processing As A Service, Wilson Higashino, Cedric Eichler, Miriam A M Capretz, Thierry Monteil, M. Beatriz F. Toledo, Patricia Stolf May 2015

Query Analyzer And Manager For Complex Event Processing As A Service, Wilson Higashino, Cedric Eichler, Miriam A M Capretz, Thierry Monteil, M. Beatriz F. Toledo, Patricia Stolf

Wilson A Higashino

Complex Event Processing (CEP) is a set of tools and techniques that can be used to obtain insights from high-volume, high-velocity continuous streams of events. CEP-based systems have been adopted in many situations that require prompt establishment of system diagnostics and execution of reaction plans, such as in monitoring of complex systems. This article describes the Query Analyzer and Manager (QAM) module, a first effort toward the development of a CEP as a Service (CEPaaS) system. This module is responsible for analyzing user-defined CEP queries and for managing their execution in distributed cloud-based environments. Using a language-agnostic internal query representation, …


Evaluation Of Particle Swarm Optimization Applied To Grid Scheduling, Wilson Higashino, Miriam Capretz, M. Beatriz Toledo May 2015

Evaluation Of Particle Swarm Optimization Applied To Grid Scheduling, Wilson Higashino, Miriam Capretz, M. Beatriz Toledo

Wilson A Higashino

The problem of scheduling independent users’ jobs to resources in Grid Computing systems is of paramount importance. This problem is known to be NP-hard, and many techniques have been proposed to solve it, such as heuristics, genetic algorithms (GA), and, more recently, particle swarm optimization (PSO). This article aims to use PSO to solve grid scheduling problems, and compare it with other techniques. It is shown that many often-overlooked implementation details can have a huge impact on the performance of the method. In addition, experiments also show that the PSO has a tendency to stagnate around local minima in high-dimensional …


Network And Energy-Aware Resource Selection Model For Opportunistic Grids, Izaias Faria, Mario Dantas, Miriam A M Capretz, Wilson Higashino May 2015

Network And Energy-Aware Resource Selection Model For Opportunistic Grids, Izaias Faria, Mario Dantas, Miriam A M Capretz, Wilson Higashino

Wilson A Higashino

Due to increasing hardware capacity, computing grids have been handling and processing more data. This has led to higher amount of energy being consumed by grids; hence the necessity for strategies to reduce their energy consumption. Scheduling is a process carried out to define in which node tasks will be executed in the grid. This process can significantly impact the global system performance, including energy consumption. This paper focuses on a scheduling model for opportunistic grids that considers network traffic, distance between input files and execution node as well as the execution node status. The model was tested in a …


Service Evolution Patterns, Shuying Wang, Wilson Higashino, Michael Hayes, Miriam A M Capretz May 2015

Service Evolution Patterns, Shuying Wang, Wilson Higashino, Michael Hayes, Miriam A M Capretz

Wilson A Higashino

Service evolution is the process of maintaining and evolving existing Web services to cater for new requirements and technological changes. In this paper, a service evolution model is proposed to analyze service dependencies, identify changes on services and estimate impact on consumers that will use new versions of these services. Based on the proposed service evolution model, four service evolution patterns are described: compatibility, transition, split-map, and merge-map. These proposed patterns provide reusable templates to encourage well-defined service evolution while minimizing issues that arise otherwise. They can be applied in the service evolution scenario where a single service is used …


Agile Methods And Request For Change (Rfc): Observations From Dod Acquisition Programs, Mary Ann Lapham, Michael S. Bandor, Eileen Wrubel May 2015

Agile Methods And Request For Change (Rfc): Observations From Dod Acquisition Programs, Mary Ann Lapham, Michael S. Bandor, Eileen Wrubel

Michael S. Bandor

This technical note is the third in an SEI series on the adoption of lean and agile methods in the DoD. Agile topics in acquisition were introduced in CMU/SEI-2010-TN-002 and CMU/SEI-2011-TN-002. This technical note extends the topics covered into the evaluation and negotiation of technical proposals that reflect iterative development approaches that in turn leverage agile methods. This framework is intended for use by government program office personnel who seek to understand evaluation approaches in this context. The information and recommendations contained in this report result from observations of defense acquisition programs wherein contractors employed iterative methods such as Agile …


Agile Methods In Air Force Sustainment: Status And Outlook, Colleen Regan, Mary Ann Lapham, Eileen Wrubel, Stephen Beck, Michael S. Bandor May 2015

Agile Methods In Air Force Sustainment: Status And Outlook, Colleen Regan, Mary Ann Lapham, Eileen Wrubel, Stephen Beck, Michael S. Bandor

Michael S. Bandor

This paper examines using Agile techniques in the software sustainment arena—specifically Air Force programs. The Software Engineering Institute has researched the viability of Agile software development methods within Department of Defense programs and barriers to the adoption of those methods for several years. How software sustainers leverage Agile methods and avoid barriers to using Agile methods are addressed in this paper. In addition, the potential use of a construct called DevOps, a blending of development and operations, is discussed.


Residual-Based Measurement Of Peer And Link Lifetimes In Gnutella Networks, Xiaoming Wang, Zhongmei Yao, Dmitri Loguinov Jan 2015

Residual-Based Measurement Of Peer And Link Lifetimes In Gnutella Networks, Xiaoming Wang, Zhongmei Yao, Dmitri Loguinov

Zhongmei Yao

Existing methods of measuring lifetimes in P2P systems usually rely on the so-called create-based method (CBM), which divides a given observation window into two halves and samples users "created" in the first half every Delta time units until they die or the observation period ends. Despite its frequent use, this approach has no rigorous accuracy or overhead analysis in the literature. To shed more light on its performance, we flrst derive a model for CBM and show that small window size or large Delta may lead to highly inaccurate lifetime distributions. We then show that create-based sampling exhibits an inherent …


Modeling Heterogeneous User Churn And Local Resilience Of Unstructured P2p Networks, Zhongmei Yao, Derek Leonard, Dmitri Loguinov, Xiaoming Wang Jan 2015

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

Zhongmei Yao

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 Lifetime Measurement In Large-Scale P2p Systems With Non-Stationary Arrivals, Xiaoming Wang, Zhongmei Yao, Yueping Zhang, Dmitri Loguinov Jan 2015

Robust Lifetime Measurement In Large-Scale P2p Systems With Non-Stationary Arrivals, Xiaoming Wang, Zhongmei Yao, Yueping Zhang, Dmitri Loguinov

Zhongmei Yao

Characterizing user churn has become an important topic in studying P2P networks, both in theoretical analysis and system design. Recent work has shown that direct sampling of user lifetimes may lead to certain bias (arising from missed peers and round-off inconsistencies) and proposed a technique that estimates lifetimes based on sampled residuals. In this paper, however, we show that under non-stationary arrivals, which are often present in real systems, residual-based sampling does not correctly reconstruct user lifetimes and suffers a varying degree of bias, which in some cases makes estimation completely impossible. We overcome this problem using two contributions: a …


In-Degree Dynamics Of Large-Scale P2p Systems, Zhongmei Yao, Daren B. H. Cline, Dmitri Loguinov Jan 2015

In-Degree Dynamics Of Large-Scale P2p Systems, Zhongmei Yao, Daren B. H. Cline, Dmitri Loguinov

Zhongmei Yao

This paper builds a complete modeling framework for understanding user churn and in-degree dynamics in unstructured P2P systems in which each user can be viewed as a stationary alternating renewal process. While the classical Poisson result on the superposition of n stationary renewal processes for n→∞ requires that each point process become sparser as n increases, it is often difficult to rigorously show this condition in practice. In this paper, we first prove that despite user heterogeneity and non-Poisson arrival dynamics, a superposition of edge-arrival processes to a live user under uniform selection converges to a Poisson process when …


Automatically Discovering The Number Of Clusters In Web Page Datasets, Zhongmei Yao Jan 2015

Automatically Discovering The Number Of Clusters In Web Page Datasets, Zhongmei Yao

Zhongmei Yao

Clustering is well-suited for Web mining by automatically organizing Web pages into categories, each of which contains Web pages having similar contents. However, one problem in clustering is the lack of general methods to automatically determine the number of categories or clusters. For the Web domain in particular, currently there is no such method suitable for Web page clustering. In an attempt to address this problem, we discover a constant factor that characterizes the Web domain, based on which we propose a new method for automatically determining the number of clusters in Web page data sets. We discover that the …


Analyzing Latency-Aware Self-Adaptation Using Stochastic Games And Simulations, Javier Camara, Gabriel A. Moreno, David Garlan, Bradley Schmerl Dec 2014

Analyzing Latency-Aware Self-Adaptation Using Stochastic Games And Simulations, Javier Camara, Gabriel A. Moreno, David Garlan, Bradley Schmerl

Gabriel A. Moreno

Self-adaptive systems must decide which adaptations to apply and when. In reactive approaches, adaptations are chosen and executed after some issue in the system has been detected (e.g., unforeseen attacks or failures). In proactive approaches, predictions are used to prepare the system for some future event (e.g., traffic spikes during holidays). In both cases, the choice of adaptation is based on the estimated impact it will have on the system. Current decision-making approaches assume that the impact will be instantaneous, whereas it is common that adaptations take time to produce their impact. Ignoring this latency is problematic because adaptations may …


Proactive Self-Adaptation Under Uncertainty: A Probabilistic Model Checking Approach, Gabriel A. Moreno, Javier Camara, David Garlan, Bradley Schmerl Dec 2014

Proactive Self-Adaptation Under Uncertainty: A Probabilistic Model Checking Approach, Gabriel A. Moreno, Javier Camara, David Garlan, Bradley Schmerl

Gabriel A. Moreno

Self-adaptive systems tend to be reactive and myopic, adapting in response to changes without anticipating what the subsequent adaptation needs will be. Adapting reactively can result in inefficiencies due to the system performing a suboptimal sequence of adaptations. Furthermore, when adaptations have latency, and take some time to produce their effect, they have to be started with sufficient lead time so that they complete by the time their effect is needed. Proactive latency-aware adaptation addresses these issues by making adaptation decisions with a look-ahead horizon and taking adaptation latency into account. In this paper we present an approach for proactive …


Reasoning About Human Participation In Self-Adaptive Systems, Javier Camara, Gabriel A. Moreno, David Garlan Dec 2014

Reasoning About Human Participation In Self-Adaptive Systems, Javier Camara, Gabriel A. Moreno, David Garlan

Gabriel A. Moreno

Self-adaptive systems overcome many of the limitations of human supervision in complex software-intensive systems by endowing them with the ability to automatically adapt their structure and behavior in the presence of runtime changes. However, adaptation in some classes of systems (e.g., safety- critical) can benefit by receiving information from humans (e.g., acting as sophisticated sensors, decision-makers), or by involving them as system-level effectors to execute adaptations (e.g., when automation is not possible, or as a fallback mechanism). However, human participants are influenced by factors external to the system (e.g., training level, fatigue) that affect the likelihood of success when they …


The Staging Transformation Approach To Mixing Initiative, Robert Capra, Michael Narayan, Saverio Perugini, Naren Ramakrishnan, Manuel A. Pérez-Quiñones Dec 2014

The Staging Transformation Approach To Mixing Initiative, Robert Capra, Michael Narayan, Saverio Perugini, Naren Ramakrishnan, Manuel A. Pérez-Quiñones

Saverio Perugini

Mixed-initiative interaction is an important facet of many conversational interfaces, flexible planning architectures, intelligent tutoring systems, and interactive information retrieval systems. Software systems for mixed-initiative interaction must enable us to both operationalize the mixing of initiative (i.e., support the creation of practical dialogs) and to reason in real-time about how a flexible mode of interaction can be supported (e.g., from a meta-dialog standpoint). In this paper, we present the staging transformation approach to mixing initiative, where a dialog script captures the structure of the dialog and dialog control processes are realized through generous use of program transformation techniques (e.g., partial …


Personalizing Interactions With Information Systems, Saverio Perugini, Naren Ramakrishnan Dec 2014

Personalizing Interactions With Information Systems, Saverio Perugini, Naren Ramakrishnan

Saverio Perugini

Personalization constitutes the mechanisms and technologies necessary to customize information access to the end-user. It can be defined as the automatic adjustment of information content, structure, and presentation tailored to the individual. In this chapter, we study personalization from the viewpoint of personalizing interaction. The survey covers mechanisms for information-finding on the web, advanced information retrieval systems, dialog-based applications, and mobile access paradigms. Specific emphasis is placed on studying how users interact with an information system and how the system can encourage and foster interaction. This helps bring out the role of the personalization system as a facilitator which reconciles …


Mining Web-Functional Dependencies For Flexible Information Access, Saverio Perugini, Naren Ramakrishnan Dec 2014

Mining Web-Functional Dependencies For Flexible Information Access, Saverio Perugini, Naren Ramakrishnan

Saverio Perugini

We present an approach to enhancing information access through Web structure mining in contrast to traditional approaches involving usage mining. Specifically, we mine the hardwired hierarchical hyperlink structure of Web sites to identify patterns of term-term co-occurrences we call Web functional dependencies (FDs). Intuitively, a Web FD ‘x y’ declares that all paths through a site involving a hyperlink labeled x also contain a hyperlink labeled y. The complete set of FDs satisfied by a site help characterize (flexible and expressive) interaction paradigms supported by a site, where a paradigm is the set of explorable sequences therein. …


Personalization By Program Slicing, Saverio Perugini, Naren Ramakrishnan Dec 2014

Personalization By Program Slicing, Saverio Perugini, Naren Ramakrishnan

Saverio Perugini

Personalization involves customizing information access to the end-user. As any new area of computer science research it lacks formal models to guide the design of systems. In this paper, we present a modeling methodology, based on generative programming, for personalizing interactions with hierarchical websites. The methodology entails modeling a user’s interaction with a site in a program and applying program slicing to personalize the interaction. While preserving interactivity, this approach does not require the designer to anticipate all possible user interactions a priori and provide interfaces for each. Moreover, it provides a theoretical, systematic, and implementation-neutral way to design systems …