ppxscal/embedding_network huggingface dataset:
Relationship of student self-directedness, computer self-efficacy, and student satisfaction to persistence in online higher education programs
Authors: Dennis Lee Robinson
Venue:  (2008)

The goal of this study was to investigate the relationship between persistence in an online program of study and self-directedness, computer self-efficacy, and student satisfaction. Online education has become a critical component in providing all types of instruction, including higher education courses and programs. With growth in this delivery method low persistence rates have surfaced as a problem with many students leaving online programs before completion. The participants in this study were students enrolled in Web-based online courses at the University of Louisville during the spring semester of 2008 (N = 258). The participants each completed a survey designed to measure self-directedness, satisfaction with learning online, computer self efficacy, and intent to persist. The method selected for this study was a correlation/prediction using linear multiple regression (ordinary least squares regression) to analyze to what extent the predictor variables predict the dependent variable. The independent variables investigated were computer self-efficacy, self-directedness, and student satisfaction along with demographic variables gender, age, college experience, online experience. The dependent variable was intention to take another online course. Findings in the present study indicated that self-directedness, computer self-efficacy, and satisfaction, were all significant predictors of intent to take additional online courses. The demographic variables also had a significant relationship to the dependent variable. Significance of the findings and implications for future research are discussed. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Indoor Positioning and Navigation with Camera Phones
Authors: Alessandro Mulloni, Daniel Wagner, Istvan Barakonyi, Dieter Schmalstieg
Venue: IEEE Pervasive Computing (2009)

This low-cost indoor navigation system runs on off-the-shelf camera phones. More than 2,000 users at four different large-scale events have already used it. The system uses built-in cameras to determine user location in real time by detecting unobtrusive fiduciary markers. The required infrastructure is limited to paper markers and static digital maps, and common devices are used, facilitating quick deployment in new environments. The authors have studied the application quantitatively in a controlled environment and qualitatively during deployment at four large international events. According to test users, marker-based navigation is easier to use than conventional mobile digital maps. Moreover, the users' location awareness in navigation tasks improved. Experiences drawn from questionnaires, usage log data, and user interviews further highlight the benefits of this approach.
Free (reaction less) torqie generation fiction or reality
Authors: Bojidar Djordjev
Venue: Proceedings of the 4th WSEAS/IASME international conference on Dynamical systems and control (2008)

This article addresses all the conventional objections concerning a based on gyroscopic effects Free (reaction less) Torque Generation and Pendulum Tests according the requirements of the NASA TM-2006-214390 AIAA-2006-4913 [1] Figures 4 and 5 accepted about rotation.
The use of a controlled wireless testbed in courses
Authors: Peter Steenkiste
Venue: ACM SIGCSE Bulletin (2009)

Wireless networking has become a popular topic in both undergraduate and graduate courses. However, putting together good assignments in wireless networking is difficult because the behavior of the wireless network depends strongly on the physical environment. We have used a wireless networking testbed based on signal propagation emulation in a number of wireless networking courses. The wireless emulator supports highly realistic experiments, while also offering a high degree of control and repeatability. This combination is very useful in a teaching context. In this paper we give an overview of the wireless emulator and we describe how it was used to support assignments and open-ended projects in several courses.
Simple a posteriori error estimators for the h-version of the boundary element method
Authors: S. Ferraz-Leite, D. Praetorius
Venue: Computing (2008)

The h-h/2-strategy is one well-known technique for the a posteriori error estimation for Galerkin discretizations of energy minimization problems. One considers to estimate the error , where is a Galerkin solution with respect to a mesh and is a Galerkin solution with respect to the mesh obtained from a uniform refinement of . This error estimator is always efficient and observed to be also reliable in practice. However, for boundary element methods, the energy norm is non-local and thus the error estimator &eta; does not provide information for a local mesh-refinement. We consider Symm’s integral equation of the first kind, where the energy space is the negative-order Sobolev space . Recent localization techniques allow to replace the energy norm in this case by some weighted L 2-norm. Then, this very basic error estimation strategy is also applicable to steer an h-adaptive algorithm. Numerical experiments in 2D and 3D show that the proposed method works well in practice. A short conclusion is concerned with other integral equations, e.g., the hypersingular case with energy space , respectively, or a transmission problem.
Bending Virtual Spring-Damper: A Solution to Improve Local Platoon Control
Authors: Jean-Michel Contet, Franck Gechter, Pablo Gruer, Abderrafiaa Koukam
Venue: Proceedings of the 9th International Conference on Computational Science: Part I (2009)

This article presents a local control approach to linear vehicle platooning. Linear platoon systems are sets of vehicles that use local or global perception capabilities to form a train configuration, without any hard grip element. Public transportation is beginning to interest in platoon systems as a technological base to conceive new services. The main problem related to platoon system's control corresponds with maintaining inter-vehicle distance. In literature, the platoon's geometry control problem is treated according to two approaches: global or local vehicle control. This paper focuses on a local approach which does not require sophisticated sensors and/or costly road equipment. This local control approach intends to obtain very good global matching to arbitrary trajectories, only from local perception which consists in measuring the vectorial distance between a given vehicle and its predecessor. The behavior of each platoon vehicle is determined from a physics inspired multi agent interaction model based on a virtual spring-damper. Furthermore, stability, platoon safety properties are checked using physics and mathematical proofs. Finally, simulation is used to measure trajectory error and inter-vehicle distance evolution.
Living with Constraints
Authors: Alan K. Mackworth
Venue: Proceedings of the 22nd Canadian Conference on Artificial Intelligence: Advances in Artificial Intelligence (2009)

In order to thrive, an agent must satisfy dynamic constraints deriving from four sources: its internal structure, its goals and preferences, its external environment and the coupling between its internal and external worlds. The life of any agent who does not respect those constraints will be out of balance. Based on this framing of the problem of agent design, I shall give four perspectives on the theme of living with constraints, beginning with a theory of constraint-based agent design and a corresponding experiment in robot architecture. Second, I shall touch briefly on a personal historical note, having lived with the evolving concept of the pivotal role of constraints throughout my research life. Third, I shall outline our work on the design of two assistive technology prototypes for people with physical and mental disabilities, who are living with significant additional constraints. Finally, I shall suggest our collective failure to recognize, satisfy and live with various constraints could explain why many of the worlds we live in seem to be out of kilter. This approach hints at ways to restore the balance. Some of the work discussed is joint with Jim Little, Alex Mihailidis, Pinar Muyan-Ozçelik, Robert St-Aubin, Pooja Viswanathan, Suling Yang, and Ying Zhang.
Binary action search for learning continuous-action control policies
Authors: Jason Pazis, Michail G. Lagoudakis
Venue: Proceedings of the 26th Annual International Conference on Machine Learning (2009)

Reinforcement Learning methods for controlling stochastic processes typically assume a small and discrete action space. While continuous action spaces are quite common in real-world problems, the most common approach still employed in practice is coarse discretization of the action space. This paper presents a novel method, called Binary Action Search, for realizing continuousaction policies by searching efficiently the entire action range through increment and decrement modifications to the values of the action variables according to an internal binary policy defined over an augmented state space. The proposed approach essentially approximates any continuous action space to arbitrary resolution and can be combined with any discrete-action reinforcement learning algorithm for learning continuous-action policies. Binary Action Search eliminates the restrictive modification steps of Adaptive Action Modification and requires no temporal action locality in the domain. Our approach is coupled with two well-known reinforcement learning algorithms (Least-Squares Policy Iteration and Fitted Q-Iteration) and its use and properties are thoroughly investigated and demonstrated on the continuous state-action Inverted Pendulum, Double Integrator, and Car on the Hill domains.
Codetrail: Connecting source code and web resources
Authors: Max Goldman, Robert C. Miller
Venue: Journal of Visual Languages and Computing (2009)

When faced with the need for documentation, examples, bug fixes, error descriptions, code snippets, workarounds, templates, patterns, or advice, software developers frequently turn to their web browser. Web resources both organized and authoritative as well as informal and community-driven are heavily used by developers. The time and attention devoted to finding (or re-finding) and navigating these sites is significant. We present Codetrail, a system that demonstrates how the developer's use of web resources can be improved by connecting the Eclipse integrated development environment (IDE) and the Firefox web browser. Codetrail uses a communication channel and shared data model between these applications to implement a variety of integrative tools. By combining information previously available only to the IDE or the web browser alone (such as editing history, code contents, and recent browsing), Codetrail can automate previously manual tasks and enable new interactions that exploit the marriage of data and functionality from Firefox and Eclipse. Just as the IDE will change the contents of peripheral views to focus on the particular code or task with which the developer is engaged, so, too, the web browser can be focused on the developer's current context and task.
Finding Funding: Grantwriting From Start to Finish, Including Project Management and Internet Use, 5th edition
Authors: Ernest W. Brewer, Charles Achilles
Venue:  (2007)

The fifth edition of this bestseller brings the reader up-to-date with newly researched Web sites and effective strategies for writing government, foundation, and private grants.
Reducing message-length variations in resource-constrained embedded systems implemented using the Controller Area Network (CAN) protocol
Authors: Mouaaz Nahas, Michael J. Pont, Michael Short
Venue: Journal of Systems Architecture: the EUROMICRO Journal (2009)

The Controller Area Network (CAN) protocol is widely used in low-cost embedded systems. CAN uses ''Non Return to Zero'' (NRZ) coding and includes a bit-stuffing mechanism. Whilst providing an effective mechanism for clock synchronization, the bit-stuffing mechanism causes the CAN frame length to become (in part) a complex function of the data contents: variations in frame length can have a detrimental impact on the real-time behaviour of systems employing this protocol. In this paper, two software-based mechanisms for reducing the impact of CAN bit stuffing are considered and compared. The first approach considered is a modified version of a technique described elsewhere (e.g. Nolte et al. [T. Nolte, H.A. Hansson, C. Norstrom, Minimizing CAN response-time jitter by message manipulation, in: Proceedings of the Eighth IEEE Real-Time and Embedded Technology and Applications Symposium (RTAS 2002), San Jose, California, 2002]). The second approach considered is a form of software bit stuffing (SBS). In both cases, not only the impact on message-length variations is addressed but also the implementation costs (including CPU and memory requirements) involved in creating practical implementation of each technique on a range of appropriate hardware platforms. It is concluded that the SBS technique is more effective in the reduction of message-length variations, but at the cost of an increase in CPU time and memory overheads and a reduction in the available data bandwidth. The choice of the most appropriate technique will, therefore, depend on the application requirements and the available resources.
A survey of biometric technology based on hand shape
Authors: Nicolae Duta
Venue: Pattern Recognition (2009)

Automated biometric systems have emerged as a more reliable alternative to the traditional personal identification solutions. One of the most popular biometrics is hand shape due to its ease of use, non-intrusiveness and public acceptance. This paper presents a survey of the technology used in hand shape-based biometric systems. We first review the component modules including the algorithms they employ. Next we discuss system taxonomies, performance evaluation methodologies, testing issues and US government evaluations. A summary of the accuracy results reported in the literature is also provided. We next describe some of the commercial hand shape biometric systems as well as some recent successful deployments. Finally, we mention a few limitations of the hand shape biometric and give some directions for future research.
Design patterns for monitoring and evaluating CSCL processes
Authors: D. Persico, F. Pozzi, L. Sarti
Venue: Computers in Human Behavior (2009)

Both quantitative and qualitative methods are being increasingly used to investigate the learning dynamics that take place within CSCL environments. Since such practices are a crucial aspect of the CSCL field, Design Patterns (DPs) can be used for capitalizing on experience and sharing know-how among practitioners. This paper describes three DP instances that have been developed and fine tuned by a community of practice consisting of researchers, instructional designers and tutors with the aim of supporting monitoring and evaluation of CSCL interactions. The DP solutions are based on a set of indicators, some of quantitative and some of qualitative nature, as well as on the methods to gauge these indicators, starting from data tracked by the e-learning system. The process of development of these DPs is described and examples of use are reported and discussed in order to advance the instructional design field and inform the development of CSCL systems. The proposed DPs belong to a Language, aimed at describing tracking problems in different types of e-learning systems and at capturing in their solutions the know-how developed by communities of experts in the different fields.
How we refactor, and how we know it
Authors: Emerson Murphy-Hill, Chris Parnin, Andrew P. Black
Venue: Proceedings of the 2009 IEEE 31st International Conference on Software Engineering (2009)

Much of what we know about how programmers refactor in the wild is based on studies that examine just a few software projects. Researchers have rarely taken the time to replicate these studies in other contexts or to examine the assumptions on which they are based. To help put refactoring research on a sound scientific basis, we draw conclusions using four data sets spanning more than 13 000 developers, 240 000 tool-assisted refactorings, 2500 developer hours, and 3400 version control commits. Using these data, we cast doubt on several previously stated assumptions about how programmers refactor, while validating others. For example, we find that programmers frequently do not indicate refactoring activity in commit logs, which contradicts assumptions made by several previous researchers. In contrast, we were able to confirm the assumption that programmers do frequently intersperse refactoring with other program changes. By confirming assumptions and replicating studies made by other researchers, we can have greater confidence that those researchers' conclusions are generalizable.
Calculi for Service-Oriented Computing
Authors: Roberto Bruni
Venue: Formal Methods for Web Services: 9th International School on Formal Methods for the Design of Computer, Communication, and Software Systems, SFM 2009, Bertinoro, Italy, June 1-6, 2009, Advanced Lectures (2009)

It is widely recognised that process calculi stay to concurrent computing as lambda-calculus stays to sequential computing; in fact, they lay abstract, rigorous foundations for the analysis of interactive, communicating systems. Nowadays, the increasing popularity of Service-Oriented Computing (SOC) challenges the quest for novel abstractions tailored to the well-disciplined handling of specific issues, like long running interactions, orchestration, and unexpected events. In fact, these features emerge neatly in most SOC applications and need to be studied as first-class aspects, whereas they would be obfuscated if dealt with by sophisticated encoding in traditional process calculi. This paper overviews some of the most recent proposals emerged in the literature, pointing out their main characteristics and presents in more detail one such proposal, called CaSPiS, by providing several examples to give evidence of its flexibility. No prior acquaintance with process calculi is assumed, indeed a gentle introduction to their basics is provided before the more advanced material be presented.
Complexity of Subsumption in the EL Family of Description Logics: Acyclic and Cyclic TBoxes
Authors: Christoph Haase, Carsten Lutz
Venue: Proceeding of the 2008 conference on ECAI 2008: 18th European Conference on Artificial Intelligence (2008)

We perform an exhaustive study of the complexity of subsumption in the EL family of lightweight description logics w.r.t. acyclic and cyclic TBoxes. It turns out that there are interesting members of this family for which subsumption w.r.t. cyclic TBoxes is tractable, whereas it is EXPTIME-complete w.r.t. general TBoxes. For other extensions that are intractable w.r.t. general TBoxes, we establish intractability already for acyclic and cyclic TBoxes.
Definability in Logic and Rough Set Theory
Authors: Tuan-Fang Fan, Churn-Jung Liau, Duen-Ren Liu
Venue: Proceeding of the 2008 conference on ECAI 2008: 18th European Conference on Artificial Intelligence (2008)

Rough set theory is an effective tool for data mining. According to the theory, a concept is definable if it can be written as a Boolean combination of equivalence classes induced from classification attributes. On the other hand, definability in logic has been explicated by Beth's theorem. In this paper, we propose two data representation formalisms, called first-order data logic (FODL) and attribute value-sorted logic (AVSL), respectively. Based on these logics, we explore the relationship between logical definability and rough set definability.
An examination of cluster identification-based algorithms for vertical partitions
Authors: Chun-Hung Cheng, Jaideep Motwani
Venue: International Journal of Business Information Systems (2009)

A major objective in database physical design is to minimise disk access in processing database transactions. Vertical partitioning is a major design approach to ensure fewer disk accesses. In this paper, we consider the use of Cluster Identification (CI)-based approaches to produce vertical partitions in database design. To produce partitions, the existing CI-based approaches either remove attributes or duplicate attributes in the branching scheme. It turns out that the former sometimes gives undesirable partitions and that the latter produces overlapping partitions. To overcome these deficiencies, we propose to remove accesses in the branching scheme. Illustrative examples are used to show the effectiveness of this branching scheme. A computational study is also conducted. In addition, the new approach is extended to deal with a vertical partition case considering frequencies of accesses.
Proceedings of the 2009 Workshop on Middleware for Ubiquitous and Pervasive Systems
Venue: ACM International Conference Proceeding Series; Vol. 389 (2009)

The research interest in the area of pervasive and ubiquitous computing has recently experienced a significant grown. Such computing scenarios include applications endowed with context awareness and adaptive capacities and sensor-instrumented environments where devices communicate through a Wireless Network. The building of software solutions for such scenarios involves a wide range of challenges due to the myriad of different applications to be considered, the specific requirements of such applications, as well as the multitude of hardware devices and communication technologies that constitute the pervasive and ubiquitous computing. In order to address such challenges, researchers should investigate different and distinct areas of computing ranging from new technologies of Wireless Sensor and Actuator Networks and context provision platforms to software engineering techniques. Initial approaches to build software for pervasive and ubiquitous computing were based on the ad-hoc development of applications specifically tailored for a target technology and hardware platform. Recently, researchers have investigated the adoption of more structured and systematic approaches of development as those based on the employment of middleware platforms. Given the current context, the Workshop on Middleware for Ubiquitous and Pervasive Systems (WMUPS) seeks to establish a forum for researches on the essential middleware services, abstractions and infrastructures as well as software engineering techniques and processes for busting the developing of software systems for pervasive and ubiquitous computing in general. Moreover, we intend to provide an effusive forum to discuss middleware concepts and services applied to a core technology in this scenario which are the Wireless Sensor and Actuator Networks (WSAN). The review process was conducted as following. Each paper was reviewed by at least three independent referees, which evaluated the works according to significance, technical content, style, clarity, and relevance to the workshop. Given the goal of a workshop of providing a forum to prospective works, we encouraged authors to submit recent and innovative ideas even if they are not still completely validated. We also suggested the reviewers of taken such goal into account when evaluating the submitted works. We had a severe conflict in one of the submitted papers which was solved by asking for a fourth review.