ppxscal/embedding_network huggingface dataset:
Improving the Aggregate Throughput of Access Points in IEEE 802.11 Wireless LANs
Authors: X. James Dong, Mustafa Ergen, Pravin Varaiya, Anuj Puri
Venue: Proceedings of the 28th Annual IEEE International Conference on Local Computer Networks (2003)

In IEEE 802.11 wireless LANs, the DCF access methodand the PCF access method operate alternatively withina superframe to service the time-varying traffic demands.Due to different medium access mechanisms deployed byDCF and PCF, they work well for some particular types oftraffic scenarios respectively, while their performance maydegrade under some other types of traffic demands. Noneof them can keep high performance under all types of trafficdemands. In this paper, we propose an adaptive control algorithmto keep the aggregate throughput of access pointsclose to the best capacity of both DCF mode and PCF modeupon various traffic requests, by dynamically adjusting theduration of DCF mode and PCF mode within a superframebased on recent traffic scenarios in wireless LANs. We modifiedthe MAC module of IEEE 802.11 wireless LANs inOPNET to support our algorithm. Extensive simulationshave been done using OPNET. The simulation results showthat high performance of access points is achieved duringthe dynamic traffic demands. The new control algorithmonly requires simple extensions to the MAC layer of accesspoints and is compatible with the MAC layer definedin IEEE 802.11 standard.
E-business security issues for SMEs in a virtual hosting environment
Authors: Neville I Williams
Venue: Proceedings of the 1st international symposium on Information and communication technologies (2003)

The Small and medium Enterprise (SME) sector is often reliant on external internet services due to their limited internal expertise in technological and other non-core business areas. As a result they are potentially more prone to overlook or be unaware of important security issues when they expand their web presence into the commercial transactions segment of e-business.In this paper the basis of those security issues will be examined with respect to the virtual web hosting environment, to clarify for e-business merchants and customers alike what the current technology does allow and to expose potential security leak sources and possible solutions. While the discussion will use Business to Consumer (B2C) as an example, the issues described are equally relevant to other forms of e-business.
Interactive Cross-Language Document Selection
Authors: Douglas W. Oard, Julio Gonzalo, Mark Sanderson, Fernando López-Ostenero, Jianqiang Wang
Venue: Information Retrieval (2004)

The problem of finding documents written in a language that the searcher cannot read is perhaps the most challenging application of cross-language information retrieval technology. In interactive applications, that task involves at least two steps: (1) the machine locates promising documents in a collection that is larger than the searcher could scan, and (2) the searcher recognizes documents relevant to their intended use from among those nominated by the machine. This article presents the results of experiments designed to explore three techniques for supporting interactive relevance assessment: (1) full machine translation, (2) rapid term-by-term translation, and (3) focused phrase translation. Machine translation was found to better support this task than term-by-term translation, and focused phrase translation further improved recall without an adverse effect on precision. The article concludes with an assessment of the strengths and weaknesses of the evaluation framework used in this study and some remarks on implications of these results for future evaluation campaigns.
Bounds on the max and min bisection of random cubic and random 4-regular graphs
Authors: J. Díaz, N. Do, M. J. Serna, N. C. Wormald
Venue: Theoretical Computer Science (2003)

In this paper, we present a randomized algorithm to compute the bisection width of cubic and 4-regular graphs. The analysis of the proposed algorithms on random graphs provides asymptotic upper bounds for the bisection width of random cubic and random 4-regular graphs with n vertices, giving upper bounds of 0.174039n for random cubic, and of 0.333333n for random 4-regular. We also obtain asymptotic lower bounds for the size of the maximum bisection, for random cubic and random 4-regular graphs with n vertices, of 1.32697n and 1.66667n, respectively. The randomized algorithms are derived from initial greedy algorithm and their analysis is based on the differential equation method.
JUTS: J-sim urban traffic simulator
Authors: David Hartman, Jaroslav Kačcer
Venue: Proceedings of the 2nd international conference on Principles and practice of programming in Java (2003)

The JUTS system is a pseudoparallel Java and J-Sim based simulation graphical tool. It deals with complex urban traffic systems from the microscopic point of view. The simulation process can be visualized, either online during its run or offline from a result file. JUTS uses XML to store maps, temporal configuration data and other description elements, that enables flexibility of use. The core of the system uses J-Sim for implementation of simulation primitives.
Agent-Based Transactions on Distributed Object Servers
Authors: Masashi Shiraishi, Tomoya Enokido, Makoto Takizawa
Venue: Proceedings of the 2003 International Conference on Computer Networks and Mobile Computing (2003)

A transactional agent is a mobile agent which manipulates objects in one or more than one object server so as to satisfy some constraint like ACID (atomicity, consistency, isolation, and durability). An agent leaves a surrogate agent on an object server on leaving the object server. A surogate holds objects manipulated by the agent and recreates an agent if the agent is faulty. We discuss how to implement transactional agents for database servers in Aglets and evaluate access time of transactional agents compared with client-server model.
Processing in-route nearest neighbor queries: a comparison of alternative approaches
Authors: Shashi Shekhar, Jin Soung Yoo
Venue: Proceedings of the 11th ACM international symposium on Advances in geographic information systems (2003)

Nearest neighbor query is one of the most important operations in spatial databases and their application domains, e.g., location-based services, advanced traveler information systems, etc. This paper addresses the problem of finding the in-route nearest neighbor (IRNN) for a query object tuple which consists of a given route with a destination and a current location on it. The IRNN is a facility instance via which the detour from the original route on the way to the destination is smallest. This paper addresses four alternative solution methods. Comparisons among them are presented using an experimental framework. Several experiments using real road map datasets are conducted to examine the behavior of the solutions in terms of three parameters affecting the performance. Our experiments show that the computation costs for all methods except the precomputed zone-based method increase with increases in the road map size and the query route length but decreases with increase in the facility density. The precomputed zone-based method shows the most efficiency when there are no updates on the road map.
Schottky--ohmic transition in nickel silicide/SiC-4H system: is it really a solved problem?
Authors: F. La Via, F. Roccaforte, V. Raineri, M. Mauceri, A. Ruggiero, P. Musumeci, L. Calcagno, A. Castaldini, A. Cavallini
Venue: Microelectronic Engineering (2003)

The transition from Schottky to ohmic contact in the nickel silicide/SiC system during annealing from 600 to 950 °C was investigated by measuring the electrical properties of the contact and by analyzing the microstructure of the silicide/SiC interface. The graphite clusters formed by carbon atoms during silicidation are uniformly distributed into the silicide layer after annealing at 600 °C and they agglomerate into a thin layer far from the silicide/SiC interface after annealing at 950 °C. At this temperature an increase of the Schottky barrier height was measured, while deep level transient spectroscopy evidences the absence of the 0.5 eV peak related to the carbon vacancies.
Numerical solution of the two-dimensional time independent Schr&#x00F6;dinger equation with exponential-fitting methods
Authors: Z. Kalogiratou, Th. Monovasilis, T. E. Simos
Venue: Proceedings of the international conference on Computational methods in sciences and engineering (2003)

The solution of the two-dimensional time-independent Schrödinger equation is considered by partial discretization. We apply exponential-fitting methods for the solution of the discretized problem which is an ordinary differential equation problem. All methods are applied for the computation of the eigenvalues of the two-dimensional harmonic oscillator and the two-dimensional Henon-Heils potential. The results are compared with the results produced by full discretization.
Integrating usability engineering into the computer science curriculum: a proposal
Authors: Evelyn P. Rozanski, Nan C. Schaller
Venue: Proceedings of the 8th annual conference on Innovation and technology in computer science education (2003)

The authors propose a model for incorporating usability engineering into the undergraduate computer science curriculum using an example curriculum from an accredited undergraduate computer science program in the United States. This model proposes that human-computer interaction and usability engineering concepts be integrated throughout the computer science curriculum rather than treated as disjoint topics.
A Novel Technique Towards Eliminating the Global Clock in VLSI Circuits
Authors: G. Hazari, M. P. Desai, A. Gupta, S. Chakraborty
Venue: Proceedings of the 17th International Conference on VLSI Design (2004)

As the feature size offered by VLSI technology shrinks,circuit performance as well as circuit complexity increases.This puts considerable pressure on the synchronousdesign methodology, mainly due to the difficultyof routing a low skew high frequency clocks signalacross a large die.On the other hand, the synchronousdesign methodology offers the benefits of amature design flow and a comprehensive set of designtools.In this paper, we present an approach towards theelimination of the global clock signal in a synchronousdesign.We present a novel partitioning strategy andthe design of a distributed asynchronous controller forthis purpose.The transformed circuit can have performancecomparable or possibly superior to the originalsynchronous circuit (provided clock could be distributedin the first place).The technique is demonstrated by apilot design in a .18 micron TSMC process, and is agood candidate for a clock-less design methodology builtaround the principle of desynchronization.
Speculating to reduce unnecessary power consumption
Authors: Enric Musoll
Venue: ACM Transactions on Embedded Computing Systems (TECS) (2003)

The power consumption of current processors keeps increasing in spite of aggressive circuit design techniques and process shrinks. One of the reasons for this increase is the complexity of the microarchitecture required to achieve the performance that each processor generation demands. These techniques, such as branch prediction and on-chip level two caches, increase not only the power consumption of the committed instructions, but also the useless power associated with those block accesses that generate results that are not needed for the correct execution and commit of the instructions.In this work, the different accesses that a particular block receives are classified into four different components, based on whether the accesses are performed by instructions of the correct path or the wrong (mispredicted) path, and also based on whether the results of the accesses are needed or not for the correct execution of the instructions. Out of the four components, only one accounts for the useful accesses to the block, that is, accesses performed to correctly execute instructions that will be committed. The other three components account for the useless activity on the block. The simulations performed indicate that, if the useless power dissipation of a high-performance processor could be totally removed with no performance degradation, the overall processor power consumption would be reduced by as much as 65&percnt; compared to the same processor in which all the blocks are accessed every cycle.This work then proposes a microarchitectural technique that targets the reduction of the useless power dissipation. The technique consists of predicting whether the result of a particular block of logic will be useful in order to execute the instructions (no matter whether the instructions will be eventually committed or not). If it is predicted useless, then the block is disabled.A case example is presented where two blocks are predicted for low power: the on-chip L2 cache for instruction fetches and the branch target buffer (BTB). The IPC versus power-consumption design space is explored for a particular microprocessor architecture. Both the average and the peak power consumption are targeted. High-level estimations are done to show that it is plausible that the ideas described might produce a significant reduction in useless block accesses. As an example, 65&percnt; accesses to the L2 cache can be eliminated at a 0.2&percnt; IPC degradation, and about 5&percnt; accesses to the BTB can be saved at the penalty of 0.7&percnt; IPC reduction.
Path search on rectangular floorplan
Authors: C. S. Ying, J. S. L. Wong, X. L. Hong, E. Q. Wang
Venue: Proceedings of the conference on European design automation (1990)

Wiring among rectangular blocks is an important component in hierarchical layout. This paper presents algorithms for path search on rectangular floorplan. A fast Steiner tree algorithm of linear complexity is proposed based on a new heuristic of converging search. Taking into account the positional distribution of terminals on the floorplan, it finds the subconnections for each terminal simultaneously and in an order independent manner; this often yields global optimum connection of terminals. Experimental results show that the new algorithm out-performs other popular sequential methods for the problem at hand in most cases.
A generator of pseudo-random numbers sequences with maximum period
Authors: Sergio Sánchez, Regino Criado, Carlos Vega
Venue: Proceedings of the international conference on Computational methods in sciences and engineering (2003)

This work presents several guidelines in order to show that it is possible to choose in an adequate manner the parameters a, b and m of the linear congruential generator xn+1 = (aċxn+b) mod m in order to maximize the period of the generated series of pseudo-random numbers, in such a manner that the period obtained is close to the theoretical upper bound of m!.
AVE: automated home video editing
Authors: Xian-Sheng HUA, Lie LU, Hong-Jiang ZHANG
Venue: Proceedings of the eleventh ACM international conference on Multimedia (2003)

In this paper, we present a system that automates home video editing. This system automatically extracts a set of highlight segments from a set of raw home videos and aligns them with user supplied incidental music based on the content of the video and incidental music. We developed an approach for extracting temporal structure and determining the importance of a video segment in order to facilitate the selection of highlight segments. Additionally we extract temporal structure, beats and tempos from the incidental music. In order to create more professional-looking results, the selected highlight segments satisfy a set of editing rules and are matched to the content of the incidental music. This task is formulated as a non-linear 0-1 programming problem and the rules are embedded as constraints. The output video is rendered by connecting the selected highlight video segments with transition effects and the incidental music.
Rotational-Position-Aware Real-Time Disk Scheduling Using a Dynamic Active Subset (DAS)
Authors: Lars Reuther, Martin Pohlack
Venue: Proceedings of the 24th IEEE International Real-Time Systems Symposium (2003)

Scheduling disk requests with service guarantees hasto bring the demand to meet guarantees in line with theneed to optimize disk utilization. This paper presents thedesign, implementation and experimental evaluation of adisk-scheduling framework which optimizes the disk utilizationunder the constraints of both hard and statistical serviceguarantees. The framework is based on two principles:1) upon each scheduling decision, the calculation ofa subset of the outstanding disk requests such that all serviceguarantees can be enforced under worst-case assumptionsand 2) the scheduling of this subset based on the rotationalposition of requests in order to improve the diskutilization. Results are presented through an implementationof the scheduling framework in DROPS, the DresdenReal-Time Operating System.
The M/G/1 FIFO Queue with Several Customer Classes
Authors: Onno J. Boxma, Tetsuya Takine
Venue: Queueing Systems: Theory and Applications (2003)

In this note we present short derivations of the joint queue length distribution in the M/G/1 queue with several classes of customers and FIFO service discipline.
Bases for projective modules in An (k)
Authors: Jesús Gago-Vargas
Venue: Journal of Symbolic Computation (2003)

Let An(k) be the Weyl algebra, with k a field of characteristic zero. It is known that every projective finitely generated left module is free or isomorphic to a left ideal. Let M be a left submodule of a free module. In this paper we give an algorithm to compute the projective dimension of M. If M is projective and rank(M) ≥ 2 we give a procedure to find a basis.
Ventricular function analysis from gated blood pool single photon emission computed tomography images
Authors: Serge D. C. Van Kriekinge
Venue:  (2003)

In this dissertation we reviewed approaches used in cardiac modeling in general and blood pool gated SPECT (BPGS) in particular, and designed two discrete models to solve specific issues associated with BPGS images such as partial volume effects and spillover, with the ultimate goal of measuring volumes and ejection fractions for the left-ventricle (LV) and right ventricle (RV). First we chose to analyze data based on its orientation within a spherical coordinate system attached to the ventricles. The dual ventricular surfaces (DVS) algorithm allowed for fine-tuning of the parameters that drive the extraction of endocardial surfaces through the selection of weight functions, but at the same time optimizing the selection of these functions can be challenging. The second model separated processing into two surface extraction problems where the expected variability of count profiles across each surface was lower than across single ventricular surfaces. The bi-ventricular and septal surfaces (BVSS) algorithm proved more robust than the DVS algorithm due to improved septal surface extraction. Because volumetric measurements are sensitive to small offsets in surface location, accuracy and reproducibility of the measurements were decreased by potential errors in surface localization. Accuracy, as measured by the difference with a &ldquo;gold standard,&rdquo; can be improved by combining automatic ROI selection using the robust BVSS surface extraction algorithm with count-based calculations within the selected region of interest (ROI). A threshold set at 35% of the maximum voxel value within the ROI, as validated by a phantom experiment, provides more accurate and more reproducible LV measurements than other techniques investigated. RV measurements demonstrated fair correlation with planar multigated acquisitions (MUGA) but a more widely accepted RV gold standard is needed for complete validation of the techniques. A limited comparison with first-pass (FP) data showed that BPGS correlated better with FP than MUGA did. The combination of a robust, automated three-dimensional ROI selection mechanism with reproducible count-based measurements opens the door to operator-independent ventricular function calculations and the phase analysis technique developed in this dissertation may in turn lead to a completely automated processing pipeline for BPGS images.
Automatic expressive lighting for interactive scenes
Authors: Ian Horswill
Venue:  (2003)

Advances in computer graphics have led to the development of interactive entertainment applications with complex 3D graphical environments. Lighting is becoming increasingly important in such applications not only because of its role in illumination, but also because of its utility in directing the viewer's gaze to important areas and evoking moods. However, lighting design is a complex process, and is especially problematic for interactive applications. Rendering time for such applications is linear in the number of lights used, thus restricting the number of lights used in real-time rendering engines to 8 or fewer; yet current practice in the animation industry is to use 32 lights or more per scene. Moreover, the scene's spatial configuration, mood, dramatic intensity, and the relative importance of different characters, all change unpredictably in real time, necessitating continual redesign as the characters and camera move. Current systems, however, use fixed, manually designed lighting. This manual design is labor intensive and leads to partially invisible characters, unmotivated or distracting color changes, and frustration for the player/audience. In this dissertation, I present a new approach to lighting design for interactive scenes. I will describe this approach using the Expressive Lighting Engine (ELE) that I have developed. ELE uses non-linear constraint optimization to automatically and unobtrusively adjust lighting in real-time, utilizing traditional cinematic and theatrical lighting design theory. This approach accommodates variations in spatial and dramatic configurations that occur during interactive scenes. ELE also allows artists to author lighting changes and override its decisions. ELE accommodates artistic desires, but also maintains style and visual continuity within an interactive scene.