bluuebunny/crossref_metadata_2025 huggingface dataset:
Emergent (mis)behavior vs. complex software systems
Authors: Mogul Jeffrey C.
Published: April 2007

Complex systems often behave in unexpected ways that are not easily predictable from the behavior of their components; this is known asemergent behavior. As software systems grow in complexity, interconnectedness, and geographic distribution, we will increasingly face unwanted emergent behavior.Unpredictable software systems are hard to debug and hard to manage. We need better tools and methods for anticipating, detecting, diagnosing, and ameliorating emergent misbehavior. These tools and methods will require research into the causes and nature of emergent misbehavior in software systems.
Automated known problem diagnosis with event traces
Authors: Yuan Chun , Lao Ni , Wen Ji-Rong , Li Jiwei , Zhang Zheng , Wang Yi-Min , Ma Wei-Ying
Published: April 2007

Computer problem diagnosis remains a serious challenge to users and support professionals. Traditional troubleshooting methods relying heavily on human intervention make the process inefficient and the results inaccurate even for solved problems, which contribute significantly to user's dissatisfaction. We propose to use system behavior information such as system event traces to build correlations with solved problems, instead of using only vague text descriptions as in existing practices. The goal is to enable automatic identification of the root cause of a problem if it is a known one, which would further lead to its resolution. By applying statistical learning techniques to classifying system call sequences, we show our approach can achieve considerable accuracy of root cause recognition by studying four case examples.
A prediction error-based hypothesis testing method for sensor data acquisition
Authors: Arici Tarik , Akgun Toygar , Altunbasak Yucel
Published: April 2007

We present a statistical method that uses prediction modeling to decrease the temporally redundant data transmitted back to the sink. The major novelties are fourfold: First, a prediction model is fit to the sensor data. Second, prediction error is utilized to adaptively update the model parameters using hypothesis testing. Third, a data transformation is proposed to bring the sensor sample series closer to weak stationarity. Finally, an efficient implementation is presented. We show that our proposed preDiction eRror bASed hypoThesis testInG (DRASTIG) method achieves low energy dissipation while keeping the prediction errors at user-defined tolerable magnitudes based on real data experiments.
Use cases modeling and software estimation
Authors: Diev Sergey
Published: April 2007

This article discusses software size/effort estimation by the Use Case Points method (UCP). It is based on the experience accumulated during deployment of the UCP in a software development department of a major financial institution. Typical for such an environment is that software is developed on top of existing applications, and that there are significant differences between projects in business domains, scope, size, complexity, project management details, etc. In a previous article [3] an extension of the Use Case Points method, called UCPm, was described that addresses these issues.Due to their level, use cases make high-level estimation easier. However, this article, presenting a number of real world situations, demonstrates that to obtain reasonably accurate estimates we need to reflect in use case models some aspects of the existing application and of the current project. It also suggests some clarifications of the concept of use case transaction and outlines some ways to support use case models consistency within and across projects.
Trustworthy software systems
Authors: Becker Steffen , Hasselbring Wilhelm , Paul Alexandra , Boskovic Marko , Koziolek Heiko , Ploski Jan , Dhama Abhishek , Lipskoch Henrik , Rohr Matthias , Winteler Daniel , Giesecke Simon , Meyer Roland , Swaminathan Mani , Happe Jens , Muhle Margarete , Warns Timo
Published: April 2007

Basic concepts and terminology for trustworthy software systems are discussed. Our discussion of definitions for terms in the domain of trustworthy software systems is based on former achievements in dependable, trustworthy and survivable systems. We base our discussion on the established literature and on approved standards. These concepts are discussed in the context of our graduate school TrustSoft on trustworthy software systems. In TrustSoft, we consider trustworthiness of software systems as determined by correctness, safety, quality of service (performance, reliability, availability), security, and privacy. Particular means to achieve trustworthiness of component-based software systems - as investigated in TrustSoft - are formal verification, quality prediction and certification; complemented by fault diagnosis and fault tolerance for increased robustness.
Agent based system development
Authors: Ranjan Prabhat , Misra A. K.
Published: April 2007

It is unlikely that a single analysis model will be able to analyze the requirements for the complete system. For capturing and analyzing the overall requirement separate models and analyst experts are needed. It is necessary to model at different level of abstraction so that both domain experts and developers can get an idea of the overall system behavior or focus on a particular part of the system in detail if required. This paper proposes a methodology, which is an improved process for requirements gathering and analysis. The proposed methodology is based on model-based techniques to provide a specific model for the type of requirements to be gathered. This methodology also provides domain-based technique, for providing a domain specific goal model for domain experts. The domain specific technique also provides multiple level of analysis and refinement process of goal in all domains by specific domain experts.
Achieving communication coverage in testing
Authors: Robinson-Mallett Christopher , Hierons Robert M. , Liggesmeyer Peter
Published: April 2007

This paper considers the problem of testing the communication between components of a timed distributed software system. We assume that communication is specified using timed interface automata and use computational tree logic (CTL) to define coverage criteria that refer to send- and receive-statements and communication paths. Given such a state-based specification of a distributed system and a concrete coverage goal, a model checker is used in order to determine the coverage provided by a finite set of test-cases, expressed using sequence diagrams. If parts of the specification remain uncovered then a goal is derived so that the model checker can be used to generate test cases that increase the coverage provided by the test suite. A major benefit of the presented approach is the generation of a potentially minimal set of test cases with the confidence that every interaction between components is executed during testing. A potential additional benefit of this approach is that it provides a visual description of the state based testing of distributed systems, which may be beneficial in other contexts such as education and program comprehension. The complexity of our approach strongly depends on the input model, the testing goal, and the model checking algorithm, which is implemented in the used tool. While a particular model checker, UPPAAL, was used, it should be relatively straightforward to adapt the approach for use with other CTL based model checkers.
SUDS
Authors: Larson Eric
Published: April 2007

SUDS is a powerful infrastructure for creating dynamic bug detection tools. Its instrumentation engine is designed in a manner that allows users to create their own correctness models quickly but is flexible to support construction of a wide range of different tools. Several static analysis phases improve the number of bugs found, the quality of the defects detected, and the run-time performance. The effectiveness of SUDS is demonstrated by showing that is capable of finding high-quality bugs with reasonable performance.
Where do bugs come from?
Authors: Schröter Adrian , Zimmermann Thomas , Premraj Rahul , Zeller Andreas
Published: April 2007

"Where do bugs in programs come from?"---this is one of the pivotal research questions in software engineering. To answer it, one can find out which parts of a program are more defect-prone than others, and then investigate which properties correlate with defect density. In other words, once we can measure the effect, we can search for its causes. Bug databases of open-source projects are a good place to begin search because they record all the problems that occurred during the projects's lifetime. However, the location of the fix (and thus the defect) is hidden in version archives and has to be extracted separately [5]. As a result one obtains a mapping from defects to code locations.
An architecture for gradual transition towards self-managed software systems
Authors: Arnautovic Edin , Kaindl Hermann , Falb Jürgen
Published: April 2007

While management of today's software systems is usually performed by humans using some user interface (UI),
autonomic systems
would be self-managed.Our research addresses the research problem of gradual transition towards self-managed software systems and proposes and investigates a particular architecture for its solution. In particular, we propose unified communication between a system to be managed and its (human or autonomic) manager. Such communication is specified using our high-level discourse metamodel based on insights from theories of human communication. This should make such communication easier to design and understand by humans.
Formal techniques in a remote voting system
Authors: Kiniry Joseph R. , Morkan Alan E. , Cochran Dermot , Oostdijk Martijn , Hubbers Engelbert
Published: April 2007

Kiezen op Afstand (KOA) is a Free Software, remote voting system developed for the Dutch government in 2003/2004. In addition to being Open Source, key components have been, or are currently being formally specified and verified. These include a tally system and a modeling of the Irish electoral system. In this paper, we describe the formal techniques incorporated during the development of components of the KOA system. It also includes continuing work including the development of a platform for trustworthy voting from a mobile phone.
Program slicing for declarative models
Authors: Uzuncaova Engin , Khurshid Sarfraz
Published: April 2007

The declarative modeling language Alloy and its automatic analyzer provide an effective tool-set for building designs of systems and checking their properties. The Alloy Analyzer performs bounded exhaustive analysis using off-the-shelf SAT solvers. The analyzer's performance hinges on the complexity of the models and so far, its feasibility has been shown only within small bounds. With the growing popularity of analyzable declarative modeling languages, in general, and Alloy, in particular, it is imperative to develop new techniques that allow the underlying solvers to scale to real systems.We present Kato, a novel technique that defines program slicing for declarative models and enables efficient analyses using existing analyzers, such as the Alloy Analyzer. Given a declarative model, Kato identifies a slice, which represents the model's
core:
a satisfying solution to the slice can be systematically extended to generate a solution for the entire model, while unsatisfiability of the core implies unsatisfiability of the entire model. The experimental results show that it is possible to achieve a significant improvement in the solving time.
Software Engineering Education (SEEd)
Authors: Henderson Peter B.
Published: April 2007

Do you read Money Magazine? If so, did you see the Money Magazine article on the Best Jobs in America? If not, did you see any news from about this article? If you are a software engineer, then can you guess what the Number 1 ranked job is? If you knew/guessed Software Engineering, then you are right. Check out http://money.cnn.com/magazines/moneymag/bestjobs/ if you don't believe it. It is very important to note that they didn't say computer science, information technology or computer programming, it was software engineering. Does this mean that our discipline is getting more noticed? More respect? Let's hope so. Also, let's hope that Money Magazine really knows what software engineering is, and what a software engineer does. You can determine that by reading the articles details of a career in software engineering yourself. Here are a few details from the article to help motivate you.
Surfing the net for software engineering notes
Authors: Doernhoefer Mark
Published: April 2007

I talk about software security on a regular basis in this column. Past articles have featured web sites addressing security design tips and techniques, security reporting sites, and other security resources available on the Internet. I'd like to stop talking about security but the subject seems to keep coming up in the press. Recent news reports on lost laptops compromising personal data, security of voting machines, new zero day exploits, and new rootkits would indicate that we are still not where we need to be in the field of software security.
Response from authors of "Design For Trustworthy Software"
Authors: Jayaswall Bijay
Published: April 2007

It is true that quality processes have not served software development well, and that is why we wrote the book, to correct the past abuses that seem to pain the reviewer. But quality is no longer the third rail of software design and development; one can now touch it and draw power from it without limiting one's career. It is also true that we are now working as consultants, but we have together spent some 80 years as university teachers of software and/or hardware development or quality process management.
Book review: Using Microsoft Windows 3, 2nd Edition by Ron Person and Karen Rose (Que Corporation, 1990)
Authors: Link Jim
Published: April 2007

If you are a newcomer to the world of using Microsoft Windows, you need this book. If you have been using Windows for a long time, you need this book, too. This book is a gold-mine of information. Each major topic has a "QuickStart" chapter for those who need to learn the application as quickly as possible. The corresponding main chapter for each application has detailed information for those who need a deeper understanding of Windows.
Comparative book review: Harvard Graphics
Authors: Marshall Ann M.
Published: April 2007

This review presents three books about Harvard Graphics. A brief review of each of the books is followed by a comparison of the three. Harvard Graphics is called HG and each title is mentioned as an underlined acronym to save space and still preserve clarity.
Book review: Macintosh Printer Secrets by Larry Pina (Hayden Books 1990)
Authors: Bruning Ronald K.
Published: April 2007

In
Macintosh Printer Secrets
, the author, Larry Pina, does a credible job of covering dot-matrix and ink-jet printing on the Macintosh. I must admit that after reading this book, it is doubtful even the most diehard Macintosh user will come away without learning something new about printers and printing on the Mac.
History lesson
Authors: Hodge H. K.
Published: April 2007

I have recently been diverted by another combination of interests -- this time programming and history.
Topics in computer-aided geometric design-1990
Authors: Franke Richard
Published: April 2007

The Ettore Majorana Centre for Scientific Culture (Center) was founded in 1963 to "give life to a completely new way of realizing the EAST-WEST-NORTH-SOUTH collaboration, without discrimination and above any ideological, political, or racial barrier." The Italian Ministry of Education, the Italian Ministry of University and Scientific Research, and the Sicilian Regional Government sponsor the center, located in Erice, Sicily. The center is named for an Italian theoretical unclear physicist, of whom Enrico Fermi said "... and then there are the geniuses like Galileo and Newton. Ettore Majorana was one of these."
Feasibility of “perfect” function evaluation
Authors: Dunham C. B.
Published: April 2007

This paper casts doubt on the feasibility of perfect subroutines or perfect hardware for mathematical functions, in particular by conversion from double precision. It suggests a slightly relaxed standard.
Applications of best approximation
Authors: Dunham Charles
Published: April 2007

We attempt to classify the known applications of the theory of best approximation so that attention can be focused on useful problems.
Book review: QuickPascal Programming by Joseph B. Wikert (Que Corporation, 1990)
Authors: Mansfield Maynard J.
Published: April 2007

According to the author, this book is written for both novice and experienced programmers. The book contains no programming exercises, however; it would not lend itself easily to use as a textbook for a class. With the exception of Chapter 1 -- which devotes a total of seventeen pages to the history of programming languages, syntax, programming technique, flowcharts, compilers, interpreters, data storage and format, RAM and ROM -- the book appears to be oriented more towards use as a reference by experienced programmers who want to learn how to use this implementation of Pascal.
Book review: 1-2-3 Release 2.2 Business Applications by Thomas Miezejeski (Que Corporation, 1989)
Authors: Seibold Gary F.
Published: April 2007

This is a book and disk set that provides templates of spreadsheets for Lotus 1-2-3 release 2.2 or 2.01. Some advanced features such as linking worksheets require release 2.2. These templates cover 13 accounting and business applications. The reader should have an intermediate to advanced knowledge of the 1-2-3 program and be familiar with accounting principles. Some of the templates contain macros and some contain custom menus. Some would need to be modified to be able to be used effectively in a business environment. They demonstrate the concepts and principles of the application but additional information for your particular business would need to be added to be practical and useful. Each worksheet can be used by itself or they can be used in combinations, an area where release 2.2's file linking is a benefit.
Book review: Hard Disk Quick Reference by Motdton, P. D. & Stanley, Timothy S. (Que Corporation, 1989)
Authors: Abunawass Adel M.
Published: April 2007

The book is divided into eight chapters and five appendices. The book starts with basic information and definitions of hard disks and their controllers. Next the book covers the hardware installation of hard disks on the IBM PC/XT/AT computers. The description is intended to give the reader a general feel and an overview of the installation process. The book provides detailed layouts and descriptions to identify the various cables and to set the proper jumpers on the controllers. The books then describes the software installation process where the hard disk is formatted and partitioned. It is recommend that the reader follows the installation instructions provided by the manufacturer of his/her particular disk when actually instaling the disk. The book then provides numerous samples of configuration and start-up files as well as a brief description of RAM disks and Cache programs.
Hodge's hypothesis
Authors: Hodge H. K.
Published: April 2007

Is there anyone who has not heard of Fermat's Last Theorem? It may be that his famous statement is not the end of the story.
Book review: Using Novell Netware by Bill Lawrence (Que Books)
Authors: Julius Tab
Published: April 2007

I must say I was pleasantly surprised when I read "Using Novell Netware". It's mistitled perhaps, because it deals entirely with the installation of networks and the network administration thereof. Yet it's certainly a book I wish I had when I was dealing with my first network.
Book review: 1-2-3 Macro Library (3rd Edition) by David Paul Ewing (QUE Corporation 1990)
Authors: Manrique Cecilia G.
Published: April 2007

This hefty 734-page book isolates a major feature of Lotus 1-2-3 which is the creation, development and use of MACROS as a tool to facilitate one's work with spreadsheets. Macros are especially useful when one realizes the number of repetitive keystrokes that can be reduced in a given work session if one only knew how and if the software package were capable of storing your keystrokes. Anymore now, most productivity packages whether they be wordprocessors, spreadsheets or databases come equipped with these keystroke-saving features called MACROS. Thus, learning how to make use of MACROS can certainly save the user a lot of keystrokes. However, one should already be proficient in the basics of spreadsheet operations before tackling this book. It assumes the reader already is well-versed in the various features of 1-2-3 and therefore does not even introduce how to create a macro in its first chapter.
Book review: The Big Mac Book by: Neil J. Salkind (Que Corporation 1989)
Authors: Bruning Ronald K.
Published: April 2007

When given the opportunity to review
The Big Mac Book
, I was exited at the possibility of picking up bits and pieces of information that I had not known before. Unfortunately, I was somewhat disappointed when I finished reading the almost-1000 page tome at what little information I had actually picked up.
Real-time integration
Authors: Hodge H. K.
Published: April 2007

That sounds somewhat redundant, doesn't it? What it means will become clear in the course of this narrative.
An object-oriented data model for partition processing in distributed databases
Authors: Mithani Rizwan
Published: April 2007

Data replication in a distributed database system can lead to inconsistencies when communication breaks down due to partition failures. Correctness can be ensured if the data model used for representing and manipulating data properly captures real-world semantics.An object-oriented data model which attempts to bridge the gap between real-world semantics and its representation is proposed. Essentially, data is stored in an attributed graph with the nodes representing real-world objects and the arcs representing the relationships between them. A superimposed rule system is employed in the model to enforce consistency and semantic constraints.The model easily incorporates partition processing strategies like Data-patching, Quorum Consensus and Failure mode integrity constraints.
Analysis and refutation of the LCAS
Authors: Kahan W.
Published: April 2007

A Language Compatible Arithmetic Standard (LCAS) has been proposed as International Standard ISO/IEC 10967:1991 for
Language Compatible Arithmetic
, Project JTC.22.28, Version 3.1 (1 March 1991), by Drs. Mary Payne and Brian Wichmann. An earlier version appeared in both ACM SIGNUM and ACM SIGPLAN 25 1 (Jan. 1990). The following remonstrance has been sent to ANSI X3-T2, the American committee in charge of the proposal:This proposed Language Compatible Arithmetic Standard is
so severely flawed that the computing world must reject it
.
Time-critical information services
Authors: Horan Thomas A. , Schooley Benjamin L.
Published: April 2007

Emergency medical services have never been more ready for the implementation of time-critical interorganizational information services for the public good.
Theoretical reflections on agile development methodologies
Authors: Nerur Sridhar , Balijepally VenuGopal
Published: April 2007

The traditional goal of optimization and control is making way for learning and innovation.
Envisioning intelligent information technologies through the prism of web intelligence
Authors: Zhong Ning , Liu Jiming , Yao Yiyu
Published: April 2007

Users and businesses alike get to turn their raw data into new science, technology, and money.
Fixing federal e-voting standards
Authors: Barr Earl , Bishop Matt , Gondree Mark
Published: April 2007

Without a threat model and a system model, voting standards cannot ensure the integrity or accuracy of the voting process.
Human-computer interaction
Authors: Carver Liz , Turoff Murray
Published: April 2007

Building the computer as part of the emergency management team ensures that people continue to do the things they do well, supported by the technology, not driven by it.
Collaborative adhocracies and mix-and-match technologies in emergency management
Authors: Mendonça David , Jefferson Theresa , Harrald John
Published: April 2007

Using the emergent interoperability approach to address unanticipated contingencies during emergency response.
The (un)predictability of computer science graduate school admissions
Authors: Ward Nigel
Published: April 2007

Providing a general calculator for students to compare where they are likely to get accepted for graduate school.
Software engineering education (SEEd)
Authors: Henderson Peter B.
Published: April 2007

In my last column I mentioned the article in Money Magazine regarding the Best Jobs in America. The number one rated job was software engineer (Check out the following URL for more information http://money.cnn.com/magazines/moneymag/bestjobs/). A number of people responded to my column and were skeptical about my optimistic viewpoint. They basically pointed out several things: First, jobs in many hot areas tend to either be cyclic or fade away (recall the line from the Beatles song 19
th
Nervous Breakdown - "your father's still perfecting ways of making sealing wax"). Second, one typically does not pursue a career in engineering just to make money. It is something one must like and enjoy as a career path. Please keep these in mind when advising students, however, I still feel optimistic about careers in software engineering for students who are interested in software development and the management of software projects.
Hacking with love
Authors: Wing Michael
Published: April 2007

I like pasta. As a kid, I ate spaghetti a couple times a week, sometimes more often. We made sauce from whatever was at hand, usually canned tomatoes and frozen hamburger, though today I prefer fancier versions like marinara made from fresh ingredients and sausage. I always enjoy sharing dinner with Edo and Patty. Patty is a fabulous cook and Edo, born and raised in Italy, is proud of, dare I say passionate about, his heritage. Edo once explained in great depth over a couple of bottles of Italian wine that what I like isn't Italian food, but an American transmogrification. I had heard comments to that effect before but, until then, I hadn't met anyone who knew enough and cared enough to explain. Then I read
Heat
, in which Bill Buford writes about making and obsessing over Italian food.
Surfing the net for software engineering notes
Authors: Doernhoefer Mark
Published: April 2007

In addition to all of the free and open source software (FOSS) and specialized information available on the web, the Internet is also a great place to get specific answers to your specific problems. There are thousands of forums where you can post a question and, hopefully, some kind soul will post a reply. These help forums vary in quality and depth of information, but if you're stuck on a particular problem, it can't hurt to toss your question out to the masses. Even if you don't get the exact answer to your question or some of the replies are dead wrong, you may benefit from the responses in that they may give you a new way of looking at the problem. You just might get that bolt of lightning you need to solve the problem by yourself.
Risks to the public
Authors: Neumann Peter G.
Published: April 2007

Edited by Peter G. Neumann (Risks Forum Moderator and Chairman of the ACM Committee on Computers and Public Policy), plus personal contributions by others, as indicated. Opinions expressed are individual rather than organizational, and all of the usual disclaimers apply. We address problems relating to software, hardware, people, and other circumstances relating to computer systems. To economize on space, we include pointers to items in the online Risks Forum: (R i j) denotes RISKS vol i number j. Cited RISKS items generally identify contributors and sources, together with URLs. Official RISKS archives are available at www.risks.org (which redirects to Newcastle and gets you nice html formatting and a search engine courtesy of Lindsay Marshall; http://catless.ncl.ac.uk/Risks/i.j.html gets you (R i j)) and at ftp://www.sri.com/risks.
The impact of research on middleware technology
Authors: Emmerich Wolfgang , Aoyama Mikio , Sventek Joe
Published: April 2007

The middleware market represents a sizable segment of the overall Information and Communication Technology market. In 2005, the annual middleware license revenue was reported by Gartner to be in the region of 8.5 billion US Dollars. In this article we address the question whether research had any involvement in the creation of the technology that is being sold in this market? We attempt a scholarly discourse. We present the research method that we have applied to answer this question. We then present a brief introduction into the key middleware concepts that provide the foundation for this market. It would not be feasible to investigate any possible impact that research might have had. Instead we select a few very successful technologies that are representative for the middleware market as a whole and show the existence of impact of research results in the creation of these technologies. We investigate the origins of web services middleware, distributed transaction processing middleware, message oriented middleware, distributed object middleware and remote procedure call systems. For each of these technologies we are able to show ample influence of research and conclude that without the research conducted by PhD students and researchers in university computer science labs at Brown, CMU, Cambridge, Newcastle, MIT, Vrije, and University of Washington as well as research in industrial labs at APM, AT&T Bell Labs, DEC Systems Research, HP Labs, IBM Research and Xerox PARC we would not have middleware technology in its current form. We summarise the article by distilling lessons that can be learnt from this evidenced impact for future technology transfer undertakings.
Estimation of travel distance from visual motion in virtual environments
Authors: Frenz Harald , Lappe Markus , Kolesnik Marina , Bührmann Thomas
Published: April 2007

Distance estimation of visually simulated self-motion is difficult, because one has to know or make assumptions about scene layout to judge ego speed. Discrimination of the travel distances of two sequentially simulated self-motions in the same scene can be performed quite accurately (Bremmer and Lappe 1999; Frenz et al., 2003). However, the indication of the perceived distance of a single movement in terms of a spatial interval results in a depth scaling error: Intervals are correlated with the true travel distance, but underestimate travel distance by about 25% (Frenz and Lappe, 2005). Here we investigated whether the inclusion of further depth cues (disparity/motion parallax/figural cues) in the virtual environment allows more veridical interval adjustment. Experiments were conducted on a large single projection screen and in a fully immersive computer-animated virtual environment (CAVE). Forward movements in simple virtual environments were simulated with distances between 1.5 and 13 m with varying speeds. Subjects indicated the perceived distance of each movement in terms of a depth interval on the virtual ground plane. We found good correlation between simulated and indicated distances, indicative of an internal representation of the perceived distance. The slopes of the fitted regression lines revealed an underestimation of distance by about 25% under all conditions. We conclude that estimation of travel distance from optic flow is subject to scaling when compared to static intervals in the environment, irrespective of additional depth cues.
Gender differences in cue preference during path integration in virtual environments
Authors: Fortenbaugh Francesca C. , Chaudhury Sidhartha , Hicks John C. , Hao Lei , Turano Kathleen A.
Published: April 2007

Three studies were conducted to examine whether men and women differ in how they recalibrate their path-integration systems when walking without vision in virtual environments. Distance cues provided by a scene and a tone, which ended each trial, were placed in conflict. Participants briefly viewed a room with a target, which was offset from their midlines and hung inside a doorframe on the far wall. After viewing, participants walked to the target's position until a tone sounded, ending the trial. In two experiments the doorframe was placed at 6 m and the tone sounded at 4 or 8 m. The rooms had minimal or photorealistic texturing applied. The third experiment used photorealistic texturing, but here the tone sounded at 6 m and the doorframe was presented at 4 or 8 m. Path angles were recorded to estimate perceived distance to the target. In all conditions tested, the women failed to scale their path angles. The men, however, scaled their path-angles with the auditory cue in the minimal-texture condition, but with the visual cue in the photorealistic-texture conditions. These results suggest that gender differences exist in the way that humans recalibrate their path-integration systems when walking without vision in virtual environments.
A feedback-controlled interface for treadmill locomotion in virtual environments
Authors: Lichtenstein Lee , Barabas James , Woods Russell L. , Peli Eli
Published: April 2007

Virtual environments (VEs) allow safe, repeatable, and controlled evaluations of obstacle avoidance and navigation performance of people with visual impairments using visual aids. Proper simulation of mobility in a VE requires an interface, which allows subjects to set their walking pace. Using conventional treadmills, the subject can change their walking speed by pushing the tread with their feet, while leveraging handrails or ropes (self-propelled mode). We developed a feedback-controlled locomotion interface that allows the VE workstation to control the speed of the treadmill, based on the position of the user. The position and speed information is also used to implement automated safety measures, so that the treadmill can be halted in case of erratic behavior.

We compared the feedback-controlled to the self-propelled mode by using speed-matching tasks (follow a moving object or match the speed of an independently moving scene) to measure the efficacy of each mode in maintaining constant subject position, subject control of the treadmill, and subject pulse rates. In addition, we measured the perception of speed in the VE on each mode.

The feedback-controlled mode required less physical exertion than self-propelled. The average position of subjects on the feedback-controlled treadmill was always within a centimeter of the desired position. There was a smaller standard deviation in subject position when using the self-propelled mode than when using the feedback-controlled mode, but the difference averaged less than 6 cm across all subjects walking at a constant speed. Although all subjects underestimated the speed of an independently moving scene at higher speeds, their estimates were more accurate when using the feedback-controlled treadmill than the self-propelled.
Heading assessment by “tunnel vision” patients and control subjects standing or walking in a virtual reality environment
Authors: Apfelbaum Henry , Pelah Adar , Peli Eli
Published: April 2007

Virtual reality locomotion simulators are a promising tool for evaluating the effectiveness of vision aids to mobility for people with low vision. This study examined two factors to gain insight into the verisimilitude requirements of the test environment: the effects of treadmill walking and the suitability of using controls as surrogate patients. Ten “tunnel vision” patients with
retinitis pigmentosa
(RP) were tasked with identifying which side of a clearly visible obstacle their heading through the virtual environment would lead them and were scored both on accuracy and on their distance from the obstacle when they responded. They were tested both while walking on a treadmill and while standing, as they viewed a scene representing progress through a shopping mall. Control subjects, each wearing a head-mounted field restriction to simulate the vision of a paired patient, were also tested. At wide angles of approach, controls and patients performed with a comparably high degree of accuracy, and made their choices at comparable distances from the obstacle. At narrow angles of approach, patients' accuracy increased when walking, while controls' accuracy decreased. When walking, both patients and controls delayed their decisions until closer to the obstacle. We conclude that a head-mounted field restriction is not sufficient for simulating tunnel vision, but that the improved performance observed for walking compared to standing suggests that a walking interface (such as a treadmill) may be essential for eliciting natural perceptually guided behavior in virtual reality locomotion simulators.
Engineering a cache-oblivious sorting algorithm
Authors: Brodal Gerth Stølting , Fagerberg Rolf , Vinther Kristoffer
Published: April 2007

This paper is an algorithmic engineering study of cache-oblivious sorting. We investigate by empirical methods a number of implementation issues and parameter choices for the cache-oblivious sorting algorithm Lazy Funnelsort and compare the final algorithm with Quicksort, the established standard for comparison-based sorting, as well as with recent cache-aware proposals. The main result is a carefully implemented cache-oblivious sorting algorithm, which, our experiments show, can be faster than the best Quicksort implementation we are able to find for input sizes well within the limits of RAM. It is also at least as fast as the recent cache-aware implementations included in the test. On disk, the difference is even more pronounced regarding Quicksort and the cache-aware algorithms, whereas the algorithm is slower than a careful implementation of multiway Mergesort, such as TPIE.
Efficient models for timetable information in public transportation systems
Authors: Pyrga Evangelia , Schulz Frank , Wagner Dorothea , Zaroliagis Christos
Published: April 2007

We consider two approaches that model timetable information in public transportation systems as shortest-path problems in weighted graphs. In the
time-expanded
approach, every event at a station, e.g., the departure of a train, is modeled as a node in the graph, while in the
time-dependent
approach the graph contains only one node per station. Both approaches have been recently considered for (a simplified version of) the earliest arrival problem, but little is known about their relative performance. Thus far, there are only theoretical arguments in favor of the time-dependent approach. In this paper, we provide the first extensive experimental comparison of the two approaches. Using several real-world data sets, we evaluate the performance of the basic models and of several new extensions towards realistic modeling. Furthermore, new insights on solving bicriteria optimization problems in both models are presented. The time-expanded approach turns out to be more robust for modeling more complex scenarios, whereas the time-dependent approach shows a clearly better performance.
To teach is to touch lives forever
Authors: Gal-Ezer Judith
Published: April 2007

The title of this talk comes from a little book that I bought years ago, compiled by S.M. Scott. It includes fictional stories and quotations about teaching, reminiscences by former pupils about their teachers, etc. The title of the book is what caught my eye, since this is how I like to view the role teachers ought to play in people's lives.I truly believe that teachers constitute the cornerstone of any successful implementation of a program of study, on any level. Moreover, I think that beyond the mastery of the actual professional material they plan to teach, good teachers should also have deep and broad knowledge of the entire subject of which that material is part, and they must have the ability to convey the material to others correctly and reliably, to provide perspective, and to infuse the students with interest, curiosity, and enthusiasm. All this requires an educator to be more of an intellectual, at least in what concerns the relevant field at large.In the talk I'll try to elaborate on the teachers' role, and to discuss the principles that should underlie a good study program, while emphasizing high school computer science curricula. Thus, I will touch upon what I think should be the core issues for computer science education research. I will also share some anecdotes from my own life, which at the time motivated me to get involved in teaching and educating, in designing computer science study programs and in their implementation, and paved the way to my doing research on teaching the fundamentals of computer science.
Dynamic object viewers for data structures
Authors: Cross James H. , Hendrix T. Dean , Jain Jhilmil , Barowski Larry A.
Published: April 2007

The jGRASP lightweight IDE has been extended to provide object viewers that automatically generate dynamic, state-based visualizations of data structures in Java. These viewers provide multiple synchronized visualizations of data structures as the user steps through the source code in either debug or workbench mode. This tight integration in a lightweight IDE provides a unique and promising environment for learning data structures. Initial classroom use has demonstrated the object viewers' potential as an aid to students who are learning to write and modify classes representing data structures. Recently completed controlled experiments with CS2 students indicate that these viewers can have a significant positive impact on student performance.
Which pointer errors do students make?
Authors: Adcock Bruce , Bucci Paolo , Heym Wayne D. , Hollingsworth Joseph E. , Long Timothy , Weide Bruce W.
Published: April 2007

A model and a taxonomy to characterize pointer manipulations are introduced, along with an instrumentation technology that leverages them to provide students with immediate reports of pointer errors in C++ programs. Data collected from CS2 student assignments show that the vast majority of student pointer errors either would not have been noticed at all, or would have been detected only much later in execution, if this infrastructure were not used. Possible applications of the underlying technology--both to conduct long-term educational research into students' understanding of pointers, and to improve pedagogy directly--are discussed.
Eccles' model of achievent-related choices
Authors: Eidelman Larisa , Hazzan Orit
Published: April 2007

Worldwide surveys indicate that the number of women studying undergraduate-level Computer Science is constantly decreasing. Based on data collected in Israel, significant differences were found in the percentages of fale high school students studying advanced-level Computer Science among different sectors. More specifically, while the percentage of fale high school students studying advanced-level Computer Science is about 50% for the Arab
minority
sector, the percentage of fale students studying Computer Science at the same level among the Jewish
majority
sector is only about 25%. This situation was investigated by using both qualitative and quantitative research tools. The paper illustrates the analysis of the data within the model of 'achievent-related choices' developed by Eccles and her colleagues.
Plagiarism detection using feature-based neural networks
Authors: Engels Steve , Lakshmanan Vivek , Craig Michelle
Published: April 2007

This paper focuses on the use of code features for automatic plagiarism detection. Instead of the text-based analyses employed by current plagiarism detectors, we propose a system that is based on properties of assignments that course instructors use to judge the similarity of two submissions. This system uses neural network techniques to create a feature-based plagiarism detector and to measure the relevance of each feature in the assessment. The system was trained and tested on assignments from an introductory computer science course, and produced results that are comparable to the most popular plagiarism detectors.
Funding opportunities in computer science education at the national science foundation
Authors: Burge Mark , Burley Diana , Taylor Harriet
Published: April 2007

We are actively seeking to increase both the number and competitiveness of proposals to NSF's Course, Curriculum, and Laboratory Improvement (CCLI) program. Funding for computer science education programs at NSF responds directly to the total proposal pressure, so increasing both the number of proposals and the competitiveness of those proposals increases the amount of funding NSF targets for computer science education.
Towards a syllabus repository for computer science courses
Authors: Tungare Manas , Yu Xiaoyan , Cameron William , Teng GuoFang , Pérez-Quiñones Manuel A. , Cassel Lillian , Fan Weiguo , Fox Edward A.
Published: April 2007

A syllabus defines the contents of a course, as well as other information such as resources and assignments. In this paper, we report on our work towards creating a syllabus repository of Computer Science courses across universities in the USA. We present some statistics from our initial collection of 8000+ syllabi. We show a syllabus creator that is integrated with Moodle [5] moodle_2006_moodle, an open-source course management system, which allows for the creation of a syllabus for a particular course. Among other information, it includes knowledge units from the Computing Curricula 2001 body of knowledge. The goal of the syllabus repository is to provide added value to the Computer Science Education community, and we present some such offerings. We conclude by presenting our future plans for the syllabus repository. These include using automated techniques to collect and classify syllabi, providing recommendations to instructors when creating a syllabus, and allowing the community to share their syllabi automatically. The syllabus collection will be part of the Computing and Information Technology Interactive Digital Educational Library (CITIDEL), a collection of the National Science Digital Library (NSDL).
InfoTraffic
Authors: Arnold Ruedi , Langheinrich Marc , Hartmann Werner
Published: April 2007

The use of suitable examples is a key to teach abstract, theoretical concepts. Interactive computer software allows us to use such examples to create attractive learning environments that not only appeal to students, but also enhance knowledge transfer in class. However, developing such highly specialized systs is costly, resulting in only few of these tools being developed for higher education. This article introduces Info Traffic, a collection of new learning environments to support the introduction offundamentalconcepts of computer science and mathatics in order to be of long-lived value. We describe the didactical concepts behind the interactive and concrete approach of Info Traffic, and illustrate th through two of its learning environments -- one targeted at propositional logic, the other at queueing theory.
A multi-expertise application-driven class
Authors: Nita-Rotaru Cristina , Dark Melissa , Popescu Voicu
Published: April 2007

In this paper we report on our experience of teaching a multi-expertise application-driven course in which upper-level undergraduate and entry-level graduate students from computer science, computer graphics technology, and educational science worked together to design, develop and evaluate a distance learning system. We describe the activities pursued in the class, the interactions between the various groups of students, as well as the challenges and advantages ensuing from the great variety of student backgrounds. The success of the course is measured in two ways. First, the class achieved the goal of building a distance learning system that surpasses the state of the art by improving the integration of the remote students into regular on-campus learning. Second, a survey conducted at the end of the course indicates that the application-driven, collaborative, and multi-expertise structure of the class provided a uniquely effective learning experience.