ppxscal/embedding_network huggingface dataset:
A new EIFS strategy for IEEE 802.11e wireless LANs
Authors: Chia-Wei Tuan, Ho-Ting Wu, Mei-Ting Chaung
Venue: Proceedings of the International Conference on Mobile Technology, Applications, and Systems (2008)

To improve the performance of IEEE 802.11e, many methods based on admission control mechanisms and adaptive contention window adjustment algorithms are proposed. In this paper, however, we do not use such typical approach to achieve this goal. Instead, we propose a new EIFS strategy for improving the performance in IEEE 802.11e. In IEEE 802.11e specification, the EIFS time delay is activated after a node initiates an unsuccessful transmission. The new EIFS strategy has the same activation mechanism as the specification. The major difference between the standard EIFS and the new EIFS strategy is when to deactivate such time delay. In specification, a node deactivates the EIFS time delay whenever any nodes in system have a successful transmission. However, in our proposed EIFS strategy, a node deactivates the EIFS time delay only when itself has a successful transmission. Performance results via simulations have shown that this new strategy is able to boost the system performance significantly over a wide range of scenarios. In addition, we analyze this strategy in details and reveal the tradeoff and the cost to implement this new strategy.
Closed-form analysis of end-to-end network delay with Markov-modulated Poisson and fluid traffic
Authors: Paolo Giacomazzi
Venue: Computer Communications (2009)

This paper develops a method for using traffic sources modelled as a Markov-modulated Poisson process (MMPP) and Markov-modulated fluid process (MMFP) in the framework of the bounded-variance network calculus, a novel stochastic network calculus framework for the approximated analysis of end-to-end network delay. The bounded-variance network calculus is an extension to multi-hop end-to-end paths of the Choe's and Shroff's Central-Limit-Theorem-based analysis of isolated network nodes. The input of the analysis is the statistical traffic envelope of sources, which is not available for generic MMPP and MMFP sources. The paper provides two statistical traffic envelopes, named two-moment and linear envelope, for general MMPP and MMFP sources, which can be used as an input of Central-Limit-Theorem-based frameworks for the analysis of network delay and, in turn, make it possible to use the rich collection of MMPP and MMFP models of voice, audio, data and video sources available in the literature. In this way, it is possible to avoid the computational complexity of traditional Markov analysis of end-to-end delay with MMPP and MMFP sources. With the linear envelope we can use simple analytical closed-form solutions for many important schedulers.
A distributed operating system for a powerful system with dynamic architecture
Authors: Steven I. Kartashev, Svetlana P. Kartashev
Venue: Proceedings of the June 7-10, 1982, national computer conference (1982)

The paper discusses the organization of a distributed operating system for dynamic architecture. It shows that the operating system must feature two types of distribution: (a) functional or vertical, whereby it is distributed among functional units in accordance with the types of conflicts that should be resolved; and (b) modular or horizontal, whereby it is distributed among modules performing the same functions. In a dynamic architecture there are three types of conflicts: memory, reconfiguration, and I/O. This leads to the division of OS into three subsystems: (1) a processor OS that resolves memory conflicts, (2) a monitor OS that resolves reconfiguration conflicts, and (c) an I/O OS that resolves all types of I/O conflicts. The paper presents a detailed organization for the processor operating system.
The Africa e-governance academy (AfeGA)
Authors: Pierre Dandjinou, Ben Akoh
Venue: Proceedings of the 2nd International Conference on Theory and Practice of Electronic Governance (2008)

This paper focuses on the creation of an e-Governance Academy for West Africa. It defines the process for the institutionalization of the academy thus far, including the stakeholder process, funding, and sustainability. It also defines the process going forward, including future partnership that must be sought, the role of the academy and its impact on countries in Africa.
Photoluminescence in n and p modulation-doped GaInNAs/GaAs quantum wells
Authors: M. Yılmaz, Y. Sun, N. Balkan, B. Ulug, A. Ulug, M. Sopanen, O. Reentilä, M. Mattila, C. Fontaine, A. Arnoult
Venue: Microelectronics Journal (2009)

Experimental results concerning the steady-state photoluminescence (PL) studies in n and p modulation doped and undoped GaInNAs/GaAs quantum wells are presented. The effects of modulation, type of doping and nitrogen concentration on the PL and the temperature dependence of the band gap, carrier localization and non-radiative recombination are investigated. Increasing the nitrogen composition decreases energy band gap as expected. The n-type modulation doping eliminates most of the defect-related effects and blue shifts the energy band gap. However, the p-type doping gives rise to additional features in the PL spectra and red shifts energy band gap further compared to the n-type-doped material.
A methodology to identify characteristics of the dynamic of mobile networks
Authors: A. Scherrer, P. Borgnat, E. Fleury, J. L. Guillaume, C. Robardet
Venue: Proceedings of the 4th Asian Conference on Internet Engineering (2008)

We propose in this paper a novel framework for the study of dynamic mobility networks. We address the characterization of dynamics by proposing an in-depth description and analysis of two real-world data sets. We show in particular that links creation and deletion processes are independent of other graph properties and that such networks exhibit a large number of possible configurations, from sparse to dense. From those observations, we propose simple yet very accurate models that allow to generate random mobility graphs with similar temporal behavior as the one observed in experimental data.
The worked-example effect: Not an artefact of lousy control conditions
Authors: Rolf Schwonke, Alexander Renkl, Carmen Krieg, Jörg Wittwer, Vincent Aleven, Ron Salden
Venue: Computers in Human Behavior (2009)

Recently it has been argued that the worked-example effect, as postulated by Cognitive Load Theory, might only occur when compared to unsupported problem-solving, but not when compared to well-supported or tutored problem-solving as instantiated, for example, in Cognitive Tutors. In two experiments, we compared a standard Cognitive Tutor with a version that was enriched with faded worked examples. In Experiment 1, students in the example condition needed less learning time to acquire a comparable amount of procedural skills and conceptual understanding. In Experiment 2, the efficiency advantage was replicated. In addition, students in the example condition acquired a deeper conceptual understanding. The present findings demonstrate that the worked-example effect is indeed robust and can be found even when compared to well-supported learning by problem-solving.
An Adaptive Memory-Based Approach Based on Partial Enumeration
Authors: Enrico Bartolini, Vittorio Maniezzo, Aristide Mingozzi
Venue: Learning and Intelligent Optimization: Second International Conference, LION 2007 II, Trento, Italy, December 8-12, 2007. Selected Papers (2008)

We propose an iterative memory-based algorithm for solving a class of combinatorial optimization problems. The algorithm generates a sequence of gradually improving solutions by exploiting at each iteration the knowledge gained in previous iterations. At each iteration, the algorithm builds an enumerative tree and stores at each tree level a set of promising partial solutions that will be used to drive the tree exploration in the following iteration.We tested the effectiveness of the proposed method on an hard combinatorial optimization problem arising in the design of telecommunication networks, the Non Bifurcated Network Design Problem, and we report computational results on a set of test problems simulating real life instances.
Computer graphics in context: an approach to a first course in computer graphics
Authors: Steve Cunningham
Venue: ACM SIGGRAPH ASIA 2008 educators programme (2008)

A context for a computer science course is defined to be a field outside computer science in which the technical course context can be used. We use the term "context" because it gives us a way to see how the computer science content and the application area relate to each other. And we say that the course is taught in context is this other field is used throughout the course for motivation, examples, and projects. We consider the idea of developing a computer graphics course in a context and discuss how that context can be used to engage students in the subject, to learn how to express ideas in the subject through computer graphics, and to build a sense of community within a class. This kind of engagement, expression, and community building are well known to make a subject more attractive as well as to broaden and deepen learning.
Subthreshold FIR Filter Architecture for Ultra Low Power Applications
Authors: Biswajit Mishra, Bashir M. Al-Hashimi
Venue: Integrated Circuit and System Design. Power and Timing Modeling, Optimization and Simulation: 18th International Workshop, PATMOS 2008, Lisbon, Portugal, September 10-12, 2008. Revised Selected Papers (2009)

Subthreshold design has been proposed as an effective technique for designing signal processing circuits needed in wireless sensor nodes powered by sources with limited energy. In this paper we propose a subthreshold FIR architecture which brings the benefits of reduced leakage energy, reduced minimum energy point, reduced operating voltage and increased operating frequency when compared with recently reported subthreshold designs. We shall demonstrate this through the design of a 9-tap FIR filter operating at 220mV with operational frequency of 126kHz/sample consuming 168.3nW or 1.33pJoules/sample. Furthermore, the area overhead of the proposed method is less than that of the transverse structure often employed in subthreshold filter designs. For example, a 9-tap filter based on transverse structure has 5&times; higher area than the filter designed using our proposed method.
Hardware-accelerated gradient noise for graphics
Authors: Josef B. Spjut, Andrew E. Kensler, Erik L. Brunvand
Venue: Proceedings of the 19th ACM Great Lakes symposium on VLSI (2009)

A synthetic noise function is a key component of most computer graphics rendering systems. This pseudo-random noise function is used to create a wide variety of natural looking textures that are applied to objects in the scene. To be useful, the generated noise should be repeatable while exhibiting no discernible periodicity, anisotropy, or aliasing. However, noise with these qualities is computationally expensive and results in a significant fraction of the run time for scenes with rich visual complexity. We propose modifications to the standard algorithm for computing synthetic noise that improve the visual quality of the noise, and a parallel hardware implementation of this improved noise function that allows the use of reduced precision arithmetic during the noise computation. The result is a special-purpose function unit for producing synthetic noise that computes high-quality noise values approximately two orders of magnitude faster than software techniques. The circuit, using a commercial CMOS cell library in a 65nm process, would run at 1GHz and consume 325μm x 325μm of chip area.
Layout decomposition for double patterning lithography
Authors: Andrew B. Kahng, Chul-Hong Park, Xu Xu, Hailong Yao
Venue: Proceedings of the 2008 IEEE/ACM International Conference on Computer-Aided Design (2008)

In double patterning lithography (DPL) layout decomposition for 45nm and below process nodes, two features must be assigned opposite colors (corresponding to different exposures) if their spacing is less than the minimum coloring spacing [11, 9, 5]. However, there exist pattern configurations for which pattern features separated by less than the minimum color spacing cannot be assigned different colors. In such cases, DPL requires that a layout feature be split into two parts. We address this problem using a layout decomposition algorithm that includes graph construction, conflict cycle detection, and node splitting processes. We evaluate our technique on both real-world and artificially generated testcases in 45nm technology. Experimental results show that our proposed layout decomposition method effectively decomposes given layouts to satisfy the key goals of minimized line-ends and maximized overlap margin. There are no design rule violations in the final decomposed layout.
Billiard instruction system for beginners with a projector-camera system
Authors: Akira Suganuma, Yusuke Ogata, Atsushi Shimada, Daisaku Arita, Rin-ichiro Taniguchi
Venue: Proceedings of the 2008 International Conference on Advances in Computer Entertainment Technology (2008)

The purpose of our work is to develop an instruction system for billiards for beginners using a projector-camera system. The direction and strength of shot are quite important in order to make the shot successful. The player's shooting stance is also important to shoot the cue-ball exactly. The direction and strength of shot and the proper shooting stance are non-symbolic information which is difficult to send to the beginner. It is generally useful that the beginner easily gets these kinds of information. We use a projector to resolve this problem. In this paper, we describe the method recognizing objects on the table, the method calculating a shooting path and shot difficulty, and the method showing the supporting information. We have confirmed experimental effectiveness of our support information.
User-focused database management
Authors: Alon Y. Halevy
Venue: Proceedings of the 13th international conference on Intelligent user interfaces (2009)

This talk describes two projects whose over goal is to make database management systems usable by a wider audience. Dataspaces aim to eliminate the upfront effort involved in creating a database. Data mangement for collaboration attempts to shift the focus of data mangement to supporting users in their natural environments and workflow.
Adaptive resource allocation for efficient patient scheduling
Authors: Ivan B. Vermeulen, Sander M. Bohte, Sylvia G. Elkhuizen, Han Lameris, Piet J. M. Bakker, Han La Poutré
Venue: Artificial Intelligence in Medicine (2009)

Objective: Efficient scheduling of patient appointments on expensive resources is a complex and dynamic task. A resource is typically used by several patient groups. To service these groups, resource capacity is often allocated per group, explicitly or implicitly. Importantly, due to fluctuations in demand, for the most efficient use of resources this allocation must be flexible. Methods: We present an adaptive approach to automatic optimization of resource calendars. In our approach, the allocation of capacity to different patient groups is flexible and adaptive to the current and expected future situation. We additionally present an approach to determine optimal resource openings hours on a larger time frame. Our model and its parameter values are based on extensive case analysis at the Academic Medical Hospital Amsterdam. Results and conclusion: We have implemented a comprehensive computer simulation of the application case. Simulation experiments show that our approach of adaptive capacity allocation improves the performance of scheduling patients groups with different attributes and makes efficient use of resource capacity.
Pointless tainting?: evaluating the practicality of pointer tainting
Authors: Asia Slowinska, Herbert Bos
Venue: Proceedings of the 4th ACM European conference on Computer systems (2009)

This paper evaluates pointer tainting, an incarnation of Dynamic Information Flow Tracking (DIFT), which has recently become an important technique in system security. Pointer tainting has been used for two main purposes: detection of privacy-breaching malware (e.g., trojan keyloggers obtaining the characters typed by a user), and detection of memory corruption attacks against non-control data (e.g., a buffer overflow that modifies a user's privilege level). In both of these cases the attacker does not modify control data such as stored branch targets, so the control flow of the target program does not change. Phrased differently, in terms of instructions executed, the program behaves 'normally'. As a result, these attacks are exceedingly difficult to detect. Pointer tainting is considered one of the onlymethods for detecting them in unmodified binaries. Unfortunately, almost all of the incarnations of pointer tainting are flawed. In particular, we demonstrate that the application of pointer tainting to the detection of keyloggers and other privacybreaching malware is problematic. We also discuss whether pointer tainting is able to reliably detect memory corruption attacks against non-control data. Pointer tainting generates itself the conditions for false positives. We analyse the problems in detail and investigate various ways to improve the technique. Most have serious drawbacks in that they are either impractical (and incur many false positives still), and/or cripple the technique's ability to detect attacks. In conclusion, we argue that depending on architecture and operating system, pointer tainting may have some value in detecting memory orruption attacks (albeit with false negatives and not on the popular x86 architecture), but it is fundamentally not suitable for automated detecting of privacy-breaching malware such as keyloggers.
Designing for Semantic Access: A Video Browsing System
Authors: Silvia Hollfelder, Andre Everts, Ulrich Thiel
Venue: Proceedings of the IEEE International Conference on Multimedia Computing and Systems - Volume 2 (1999)

Users of browsing applications often have vague information needs which can only be described in conceptual terms. Therefore, a video browsing system must accept conceptual queries for preselection and offer mechanisms for interactive inspection of the result set by the user. In this paper, we describe a MM-DBMS that we extended with the following components: The retrieval engine calculates relevance values for the results of a conceptual query by feature aggregation on video shot granularity to offer conceptual, content-based access. An intelligent client buffer strategy employs these relevance values to enable flexible user interactions during browsing. The admission control module admits whole browsing sessions by predicting required resources from query results to reduce startup delays within a session.
Image, appearance and vanity in the use of media spaces and video conference systems
Authors: Jose Eurico de Vasconcelos Filho, Kori M. Inkpen, Mary Czerwinski
Venue: Proceedings of the ACM 2009 international conference on Supporting group work (2009)

Media spaces and videoconference systems are beneficial for connecting separated co-workers and providing rich contextual information. However, image sharing communication tools may also touch on sensitive spots of the human psyche related to personal, perceived image issues (e.g., appearance, self-image, self-presentation and vanity). We conducted two user studies to examine the impact of self-image concerns on the use of media spaces and videoconference systems. Our results suggest that personal, perceived image concerns have a considerable impact on the comfort level of users and may hinder effective communication [8]. We also found that image filtering techniques can help users feel more comfortable. Our results revealed that distortion filters, which are frequently cited to help preserve privacy, do not tend to be the ones preferred by users. Instead, users seemed to favor filters that make subtle changes to their appearance, or, in some instances, they preferred to use a surrogate instead.
Removing Node Overlaps Using Multi-sphere Scheme
Authors: Takashi Imamichi, Yohei Arahori, Jaeseong Gim, Seok-Hee Hong, Hiroshi Nagamochi
Venue: Graph Drawing: 16th International Symposium, GD 2008, Heraklion, Crete, Greece, September 21-24, 2008. Revised Papers (2009)

In this paper, we consider the problem of removing overlaps of labels in a given layout by changing locations of some of the overlapping labels, and present a new method for the problem based on a packing approach, called multi-sphere scheme. More specifically, we study two new variations of the label overlap problem, inspired by real world applications, and provide a solution to each problem. Our new approach is very flexible to support various operations such as translation, translation with direction constraints, and rotation. Further, our method can support labels with arbitrary shapes in both 2D and 3D layout settings. Our extensive experimental results show that our new approach is very effective for removing label overlaps.
Conditional fault hamiltonian connectivity of the complete graph
Authors: Tung-Yang Ho, Yuan-Kang Shih, Jimmy J. M. Tan, Lih-Hsing Hsu
Venue: Information Processing Letters (2009)

A path in G is a hamiltonian path if it contains all vertices of G. A graph G is hamiltonian connected if there exists a hamiltonian path between any two distinct vertices of G. The degree of a vertex u in G is the number of vertices of G adjacent to u. We denote by @d(G) the minimum degree of vertices of G. A graph G is conditional k edge-fault tolerant hamiltonian connected if G-F is hamiltonian connected for every F@?E(G) with |F|==3. The conditional edge-fault tolerant hamiltonian connectivity HC"e^3(G) is defined as the maximum integer k such that G is k edge-fault tolerant conditional hamiltonian connected if G is hamiltonian connected and is undefined otherwise. Let n>=4. We use K"n to denote the complete graph with n vertices. In this paper, we show that HC"e^3(K"n)=2n-10 for n@?{4,5,8,10}, HC"e^3(K"4)=0, HC"e^3(K"5)=2, HC"e^3(K"8)=5, and HC"e^3(K"1"0)=9.
Optimal distributed real-time scheduling of flexible manufacturing networks modeled as hybrid dynamical systems
Authors: A. V. Savkin, J. Somlo
Venue: Robotics and Computer-Integrated Manufacturing (2009)

The paper considers a class of flexible manufacturing networks. We employ hybrid dynamical systems to model such networks. The main and new achievement of the paper is that we propose a distributed implementable in real time scheduling rule such that the corresponding closed-loop system is stable and optimal. In stable systems the processes converge to periodic ones. The paper gives computing relations for the determination of the parameters of the periodic processes. These are very much suitable for planning purposes. On this basis-and this, we consider, is also a new, significant result-optimal arrival (demand) rates determination method is proposed. Quality characteristics are outlined. Field of application of hybrid dynamical approach for FMS scheduling is analyzed. The results open perspectives for MRP level task planning. Example and simulation results are presented.
Global asymptotic stability analysis of nonlinear differential equations in hybrid bidirectional associative memory neural networks with distributed time-varying delays
Authors: Yongqiang Zhou, Shouming Zhong, Mao Ye, Zhiyuan Shi
Venue: Neurocomputing (2009)

In this paper, the problem on an unique equilibrium solution of the bidirectional associative memory neural networks with distributed time-varying delays is investigated via Lyapunov stability theory. By using topological degree theory and M-matrix theory, several sufficient conditions ensuring the existence, uniqueness and global asymptotic stability of equilibrium solution are derived. An illustrative example is given to demonstrate the effectiveness of the obtained results.