ppxscal/embedding_network huggingface dataset:
A phenomenographic study of students' attitudes toward the use of multiple media for learning
Authors: Stavros Demetriadis, Evangelos Triantfillou, Andreas Pombortsis
Venue: Proceedings of the 8th annual conference on Innovation and technology in computer science education (2003)

Multimedia offer a variety of coding formats for presenting information and this variability is generally valued as a positive characteristic of any multimedia learning environment. This study investigates the idea that students' attitudes concerning the use of multiple media for learning exhibit a considerable variability (different feelings, modes of use, preferences and dislikes) and information about these various stances may help designers and educators to better integrate and use multiple media for educational purposes. Employing a phenomenographic research methodology students' attitudes were recorded, categorised and related to parameters such as their learning styles. Results of the study indicate that a) visual dynamic media (animation and digital movies) capture students' interest and generate subjective feelings of better learning, b) digital movies may enhance the perceived authenticity of the educational setting and this also increases students' interest, c) students transfer to the digital medium the need for learning techniques that they use in the printed medium and experience feelings of restriction if the environment does not adequately support the same techniques or satisfactory alternatives, d) acceptance of audio varies significantly depending on perceptual preferences of students and e) students displaying a high abstract conceptualisation learning style express preference for studying more abstract content using printed matter.
Analysis and Optimization of Enhanced MTCMOS Scheme
Authors: Rahul M. Rao, Jeffrey L. Burns, Richard B. Brown
Venue: Proceedings of the 17th International Conference on VLSI Design (2004)

Stacking of "off" transistors has been shown to reducesub-threshold leakage of the stack. This paper presents ananalysis of optimal selection of device widths for suchstacked configurations for total leakage reduction. Weshow that forced stacking always results in an increase ingate leakage if identical performance is desired. Wefurther present an analysis of optimal width ratios for sub-thresholdand gate leakage reduction, and derive boundson the input occurrence probability that ensures totalleakage reduction with forced stacking. We demonstratethat leakage is greatly minimized if the stack is optimizedfor gate leakage rather than for sub-threshold leakage.Finally, we investigate optimization for total leakage andshow that as gate leakage becomes dominant, optimizationfor gate leakage will be identical to total leakageoptimization.
Financial evaluation of information systems investments
Authors: Charlene A. Dykman
Venue: Technologies & methodologies for evaluating information technology in business (2003)

Information systems represent a significant investment for most organizations, regardless of the industry. Managers need to understand that the decision to spend millions, or billions, of dollars on an information system should be analyzed just like any other major purchase. It seems that general management often just "gives in" to the "expert power" of the technologists, both internal and external to the organization. Calculating the Return on Investment (ROI) of an information system acquisition may not be quite as simple or straightforward as doing so for other capital expenditures. However, it is still possible, and necessary, to do the financial analysis. Discussed in this chapter are the issues involved in evaluating information system investment decisions as well as the applicability of various financial measures to evaluation of IS projects.
A Mille Plateaux manifesto
Authors: Achim Szepanski
Venue: Organised Sound (2001)

The label Mille Plateaux focuses on concepts like virtuality, noise, machinism and digitality. In the most simple case, digital music simulates something that does not exist as a reality; it generates something new. It is the result of the teamwork of numerous authorities such as the 'musician', the programmer and the authority of the software program. Today, computer digital music can be seen as screen-based music, i.e. sounds become visible and images audible, but one can often forget that there is no mutual correspondence; and that this is simply a mechanism whereby a given program secretly directs the programmer towards significant ways of performing, creating apparently absolute relationships between image and sound. On the other hand, with the increasing complexity of software, the programmer loses insight into internal communication structures. Such complex programs are full of errors and can even act on their own initiative. Programmers and musicians who navigate through today's systems function as designers. But this is less a question of the design of a program's operation surfaces but of the programming of software and the navigation by its logic. One has to discuss the medial conditions of digital music, the more user-friendly the software, the less transparent is the medium itself; i.e. the more transparent the functions of a computer or a synthesizer (say, with the use of preset sounds), the stronger the medium proves to be non-transparent. Digital music is more about opening up given program structures; internal ramifications and program hierarchies are to be discovered.
Vector Associative Memory Models
Authors: B. V. Kryzhanovskii, L. B. Litinskii
Venue: Automation and Remote Control (2003)

The Hopfield model effectively stores a comparatively small number of initial patterns, about 15% of the size of the neural network. A greater value can be attained only in the Potts-glass associative memory model, in which neurons may exist in more than two states. Still greater memory capacity is exhibited by a parametric neural network based on the nonlinear optical signal transfer and processing principles. A formalism describing both the Potts-glass associative memory and the parametric neural network within a unified framework is developed. The memory capacity is evaluated by the Chebyshev&ndash;Chernov statistical method.
An exploratory study of the differences between face-to-face and computer-mediated reference interactions
Authors: Charlotte Elizabeth Ford
Venue:  (2003)

This research furthers our understanding of reference service in the networked, digital library by addressing the question: How do face-to face reference interactions differ from computer-mediated reference interactions? A library was identified which offered face-to-face, e-mail, and chat reference service. Twelve librarians were observed as they provided all three types of service, for a period of three weeks. Over 100 face-to-face interactions were tape recorded and transcribed. E-mail and real-time computer interactions from the same time period (over 100 in each medium) were captured and stripped of identifying information. The data were then entered into a QSR database. Content analysis and discourse analysis were used to determine how the types of questions asked by users varied across media; how the types of responses varied across media; and how interactivity varied across media. Observations and brief interviews were also used to document these differences. While library users in face-to-face interactions asked more questions, similarities were found in the types of substantive questions asked across media. Librarians responding face-to-face were more likely to verify understanding, to draw users into interactions, and to instruct users. A wider variety of sources was used, collaborative use of sources was more common, and the number of back-and-forth exchanges was higher in face-to-face interactions. Computer-mediated interactions were more time consuming; fewer words were exchanged, but the exchange was more balanced. Chat reference service was found to hold promise for question negotiation.
A Hybrid Descent Method for Global Optimization
Authors: K. F. C. Yiu, Y. Liu, K. L. Teo
Venue: Journal of Global Optimization (2004)

In this paper, a hybrid descent method, consisting of a simulated annealing algorithm and a gradient-based method, is proposed. The simulated annealing algorithm is used to locate descent points for previously converged local minima. The combined method has the descent property and the convergence is monotonic. To demonstrate the effectiveness of the proposed hybrid descent method, several multi-dimensional non-convex optimization problems are solved. Numerical examples show that global minimum can be sought via this hybrid descent method.
Transaction management in Hermes
Authors: D. P. Bradshaw, R. L. Sunday, P. Å. Larson
Venue: Proceedings of the 1991 conference of the Centre for Advanced Studies on Collaborative research (1991)

The main objective of our research is to provide efficient mechanisms for storing and accessing bulk data using Hermes. The approach is to provide concurrent access to large shared data stores within and outside the Hermes environment. We propose that this could be achieved practically by creating a transaction abstraction within Hermes that will allow atomic access to internally shared data and participation in transactions with other non-Hermes environments.This paper outlines a method for integrating transaction management, lock management and recovery management facilities within Hermes. Integration takes place in two phases. First, we present our model of the transaction abstraction within the Hermes programming environment. Then, we outline an implementation of the abstraction based on Camelot primitives within the Hermes runtime environment.
Digital media in computer science curricula
Authors: Yue-Ling Wong, Jennifer Burg, Victoria Strokanova
Venue: ACM SIGCSE Bulletin (2004)

"Digital media" is one of those unfortunate terms that means different things in different contexts. This difficulty of definition -- along with its association with art, communication, architecture, and film -- puts digital media on the margins of traditional computer science curricula. This paper reviews the types of digital media programs current in higher education; proposes a curriculum model for digital media instruction that is firmly grounded in computer science at the same time that it interfaces easily with digital art; and describes specially-designed course material that serves the interdisciplinary need while preserving the rigor of the computer science discipline.
Computational models for defenses against internet-based attacks
Authors: Kathleen M. Carley
Venue:  (2003)

Internet-based attacks have become an important concern to the government and business since more systems are reliant upon the Internet to exchange information. In particular, distributed denial of service (DDOS) attacks have been used as a prevalent way to compromise the availability of networks or information services. The economic incentives of Internet Service Providers (ISPs) to provide DDOS defenses and the public policy concerns to deploy these defenses have not been formally investigated previously. Security services, such as Virtual Private Networks, have been provided by ISPs as optional network services to deal with the secrecy of data transportation. In the case of DDOS attacks, ISPs provide DDOS defenses that ensure the availability of the subscribers' online services. This dissertation proposes that ISPs provide DDOS defenses on their network as security services to their subscribers and studies the service models for providing the defenses and the public policies needed to facilitate the provision of the defenses. The focus will be on the DDOS defenses that actively filter out ongoing attack traffic. This dissertation analyzes how the side effects of defenses influence the provision of the defenses and investigates the economic incentives for the service provision. The contributions of this dissertation are as follows: First, this dissertation categorizes the current defenses that actively respond against DDOS attacks at network routers based on attack detection algorithms and attack responses. Secondly, the service provision model is analyzed based on the performance efficiency of DDOS defenses under various network topologies and various settings in the technology. Next, the economic incentives for ISPs to offer defense services are then analyzed based on empirical data. To operate the DDOS defense services cost effectively, ISPs should set the filter location closer to the attack sources and price subscribers based on their willingness to pay. Finally, cooperation among multiple ISPs on providing the defenses is analyzed. In order to improve the quality of the defenses when attacks are distributed, ISPs should cooperate with other highly influential ISPs. Public policies should encourage source filtering and provide incentives for highly influential ISPs to deploy DDOS defenses.
A simple and energy-efficient routing protocol for radio networks
Authors: Amitava Datta, Subbiah Soundaralakshmi
Venue: Proceedings of the 2003 ACM symposium on Applied computing (2003)

A radio network (RN) is a distributed system where each node is a small hand-held commodity device called a station, running on batteries. Each station spends energy while transmitting or receiving a message i.e., when the station is awake. A station conserves power by going into a sleep mode. Since it is not possible to recharge batteries when the stations are on a mission, it is extremely important that the stations spend energy only when it is necessary. In this paper, we design an energy-efficient protocol for permutation routing on a single-hop radio network, where each station is within the transmission range of all other stations. An instance of the permutation routing problem involves p stations of an RN, each storing n/p packets. Each packet has a unique destination address which is the identity of the destination station to which the packet should be sent. Our goal is to route all the packets to their destinations while spending as little energy as possible. From simulation results, it is clear that our protocol performs better than an existing protocol by Nakano et al. [12], when each station routes packets with random destination addresses. We also assume that k &laquo; p &laquo; n, where, n, p and k are respectively the number of packets, number of stations and number of channels in the network.
Performance Analysis of IP Paging Protocol in IEEE 802.11 Networks
Authors: Sangheon Pack, Ved Kafle, Yanghee Choi
Venue: Proceedings of the 28th Annual IEEE International Conference on Local Computer Networks (2003)

Recently, IEEE 802.11 wireless networks have beenwidely deployed in public areas for mobile Internet services.In the public wireless LAN systems, paging functionis necessary to support various advanced services (e.g.Voice over IP and message applications) and to provide efficientpower management scheme. In next-generation mobilenetworks, the so-called all-IP networks, the pagingfunction will be supported in the IP layer (i.e. IP paging).When IP paging protocol is deployed in IEEE 802.11 wirelessnetworks, it may utilize the power saving mechanismsupported in the IEEE 802.11 standard for more efficientpower management. However, since the current power savingmechanism is based on a periodical wake-up mechanismwith a fixed interval, it is difficult to optimize the powersaving performance. In this paper, we analyze the performanceof IP paging protocol over IEEE 802.11 Power SavingMode (PSM). We define a wake-up cost and a pagingdelay cost. Then, we study the effect of varying the lengthof the wake-up interval and the session arrival rate. Inaddition, we analyze the distribution of the session blockingprobability due to the coarse-grained wake-up interval.Also, we investigate the optimal wake-up interval to minimizethe total cost through simulations. These results indicatethat it is necessary to find the optimal wake-up intervalin order to minimize the total cost while satisfying the givenpaging delay constraints.
A-mediAS: an adaptive event notification system
Authors: Annika Hinze
Venue: Proceedings of the 2nd international workshop on Distributed event-based systems (2003)

Event Notification Services inform about the occurrences of events that are of special interest for their users. Upcoming systems for event notification cover multiple applications and integrate event data from different sources. A Main challenge is the evaluation of user profiles under various and changing application requirements. Of particular interest are (1) the profile evaluation using differing semantics and (2) high filter performance under changing system load. This paper introduces the design and implementation of A-mediAS -- an adaptive event notification system. We present a case study of a remote monitoring application, which shows the effective adaptation of the evaluation semantics in A-mediAS. We describe different event filtering strategies and show their adaptation to varying event and profile distributions. Finally, we analyze the filter performance for different workload scenarios.
Formal Verification of C Language Based VLSI Designs
Authors: Masahiro Fujita
Venue: Proceedings of the 17th International Conference on VLSI Design (2004)

This paper discusses about formal verification techniquestargeting C based VLSI design descriptions. Recently there arelots of attentions into the use of C programming language (or itsextensions) for describing hardware as well as software with anintention to support hardware-software co-design processes with asingle language. Here we first discuss about such designmethodologies by which system level descriptions for hardware-softwarecombined systems can be uniformly and smoothlyrefined into implementation in RTL for hardware and assemblylanguages for software. Starting from regular C programminglanguage descriptions, the design methodologies repeat a numberof small refinement steps and gradually adding more and moredetails into the target designs. We also discuss about formalverification of system level descriptions in those designmethodologies from the viewpoint of formal verification. Sincesuch descriptions have essentially concurrency and C must beextended to be able to represent such concurrency, an effectiveand efficient formal verification of synchronization of concurrentprocesses is one of the most important issues in system leveldesigns. We present model checking and equivalence checkingmethods targeting the design methodology that can checkcorrectness of design descriptions with preliminary experimentalresults. The proposed formal verification methods will support thedesign methodologies and are very efficient by utilizing the factthat the design methodologies consist of lots of small refinementsteps.
Outdoor virtual reality
Authors: Bruce H. Thomas, Wayne Piekarski
Venue: Proceedings of the 1st international symposium on Information and communication technologies (2003)

This paper presents our novel concept Outdoor Virtual Reality. By using outdoor augmented reality techniques we propose to build very wide area virtual reality systems, outdoor virtual reality. The concept of outdoor virtual reality is compared and contrasted to traditional definitions of augmented reality and virtual reality. We present our flexible Tinmith-evo5 software architecture as a platform to build outdoor virtual reality applications. We have constructed two outdoor virtual reality applications, a 3D visualisation tool and an outdoor game.
An ethnographic, action-based approach to human experience in virtual environments
Authors: Anna Spagnolli, Diego Varotto, Giuseppe Mantovani
Venue: International Journal of Human-Computer Studies (2003)

This paper addresses a sensitive issue, of presence experienced by people interacting with a virtual environment (VE). Understanding 'presence', both theoretically and empirically, is important for designers interested in building effective computer-mediated environments for learning and work activities. The concept of presence has been treated mostly as a state of mind, to be investigated through 'objective' and 'subjective' measurement devices. The authors propose to add a different approach, which can address presence as an action-based process. This approach considers presence as the ongoing result of the actions performed in an environment and the local and cultural resources deployed by actors. In this sense, 'presence' can be captured by monitoring the sequence of participants' actions and the aspects of the environment that are involved in this process; discourse/interaction analysis represents a fitting method for this goal. Sequences of interaction with a virtual library are used to illustrate some core aspects of an ethnographic, action-based approach to presence, such as the action possibilities envisaged by participants, the configuration of the virtual objects, the norms that regulate the interaction, the resources that are imported in the VE. These aspects are a necessary step to understand users' presence in the VE and to plan consequent interventions to ameliorate the design of the interface.
Data Placement and Query Processing Based on RPE Parallelisms
Authors: Yaxin Yu, Guoren Wang, Ge Yu, Gang Wu, Junan Hu, Nan Tang
Venue: Proceedings of the 27th Annual International Conference on Computer Software and Applications (2003)

The basic idea behind parallel database systems is toperform operations in parallel to reduce the response timeand improve the system throughput. Data placement is a keyfactor on the performance of parallel database systems. Thispaper proposes two data partition strategies to declusterXML documents with very large size, Path Schema basedPath Instance Balancing (PSPIB) strategy, in which allpath instances with the same path schema in a data tree aredeclustered evenly over all sites, and Node Schema basedNode Round-Robin (NSNRR) strategy, in which all nodeobjects with the same node schema in a data tree aredeclustered over all sites in a round-robin way. Accordingly,two query processing algorithms are proposed based on thetwo partition methods, Parallel Path Merge (PPM)algorithm and Parallel Pipelining Path Join (PPPJ)algorithm. The performance analysis and evaluation on thetwo data placement strategies and corresponding queryprocessing algorithms are given in this paper.
How to look busy while being as lazy as ever: the Implementation of a lazy functional debugger
Authors: Henrik Nilsson
Venue: Journal of Functional Programming (2001)

This article describes the implementation of a debugger for lazy functional languages like Haskell. The key idea is to construct a declarative trace which hides the operational details of lazy evaluation. However, to avoid excessive memory consumption, the trace is constructed one piece at a time, as needed during a debugging session, by automatic re-execution of the program being debugged. The article gives a fairly detailed account of both the underlying ideas and of our implementation, and also presents performance figures which demonstrate the feasibility of the approach.
On an approximate minimax circle closest to a set of points
Authors: Saul I. Gass, Christoph Witzgall
Venue: Computers and Operations Research (2004)

We show how the Chebychev minimax criterion for finding a circle closest to a set of points can be approximated well by standard linear programming procedures.