ppxscal/embedding_network huggingface dataset:
Multi-scale plasma simulation by the interlocking of magnetohydrodynamic model and particle-in-cell kinetic model
Authors: Tooru Sugiyama, Kanya Kusano
Venue: Journal of Computational Physics (2007)

Many kinds of simulation models have been developed to understand the complex plasma systems. However, these simulation models have been separately performed because the fundamental assumption of each model is different and restricts the physical processes in each spatial and temporal scales. On the other hand, it is well known that the interactions among the multiple scales may play crucial roles in the plasma phenomena (e.g. magnetic reconnection, collisionless shock), where the kinetic processes in the micro-scale may interact with the global structure in the fluid dynamics. To take self-consistently into account such multi-scale phenomena, we have developed a new simulation model by directly interlocking the fluid simulation of the magnetohyrdodynamics (MHD) model and the kinetic simulation of the particle-in-cell (PIC) model. The PIC domain is embedded in a small part of MHD domain. The both simulations are performed simultaneously in each domain and the bounded data are frequently exchanged each other to keep the consistency between the models. We have applied our new interlocked simulation to Alfven wave propagation problem as a benchmark test and confirmed that the waves can propagate smoothly through the boundaries of each domain.
Intelligent fuzzy distance and cruise control for passenger cars
Authors: Henning Holzmann, Stefan Germann, Christoph Halfmann, Rolf Isermann
Venue: Journal of Intelligent Fuzzy Systems: Applications in Engineering and Technology (1998)

As individual and commercial traffic flow on roads and highways grows enormously the number of traffic jams and accidents increases as well. Therefore, modern vehicle research is not only focused on adapting driving comfort to the growing traffic density in order to retain the advantages of individualized mobility, but also on improving passengers' safety. One way to improve safety and comfort of manually driven cars is to assist the driver by an Adaptive Distance and Cruise Control system (ACC). This paper deals with the design and implementation of a combined control structure using conventional techniques for vehicle acceleration control on the one hand and fuzzy control algorithms for vehicle velocity and intervehicle distance control on the other hand. In this application, the major advantage using a fuzzy representation is the possibility to describe the subjective comfort and safety demands of drivers by linguistic formulation.
Genetic programming of conventional features to detect seizure precursors
Authors: Otis Smart, Hiram Firpi, George Vachtsevanos
Venue: Engineering Applications of Artificial Intelligence (2007)

This paper presents an application of genetic programming (GP) to optimally select and fuse conventional features (C-features) for the detection of epileptic waveforms within intracranial electroencephalogram (IEEG) recordings that precede seizures, known as seizure precursors. Evidence suggests that seizure precursors may localize regions important to seizure generation on the IEEG and epilepsy treatment. However, current methods to detect epileptic precursors lack a sound approach to automatically select and combine C-features that best distinguish epileptic events from background, relying on visual review predominantly. This work suggests GP as an optimal alternative to create a single feature after evaluating the performance of a binary detector that uses: (1) genetically programmed features; (2) features selected via GP; (3) forward sequentially selected features; and (4) visually selected features. Results demonstrate that a detector with a genetically programmed feature outperforms the other three approaches, achieving over 78.5% positive predictive value, 83.5% sensitivity, and 93% specificity at the 95% level of confidence.
Domain-Specific Information Retrieval Based on Improved Language Model
Authors: Kai Kang, Kunhui Lin, Changle Zhou, Feng Guo
Venue: Proceedings of the Fourth International Conference on Fuzzy Systems and Knowledge Discovery - Volume 02 (2007)

There are two key ingredients in the general framework of language models used in information retrieval, one is importance weighting, the other is word relationship computing. A series of improvements are made to these ingredients of the general framework of language models which is used in domain-specific information retrieval. First, an EM algorithm is proposed to estimate the importance weights of query terms, and the Bayesian smoothing is used to compute the productive probabilities of important terms. Next, a new algorithm based on Dynamic Bayesian Network is proposed for obtaining the explanation probabilities between terms. Experiment shows that the improved model performs remarkably better for domain-specific information retrieval than some traditional retrieval techniques, and the extended framework has good expansibility.
Mesh Simplification Algorithm Based on Quadrangle Collapse
Authors: Hua-hong Chen, Xiao-nan Luo, Ruotian Ling
Venue: Proceedings of the Fourth International Conference on Image and Graphics (2007)

Many applications of Virtual Reality require 3D models. In this paper, quadrangles in the triangle mesh are defined. We put forward a quadrangle collapse based mesh simplification algorithm which can rapidly produce high approximations of 3D models. The algorithm uses iterative collapse of quadrangle to simple models and maintains surface error approximations using quadric matrices. Three vertices and six faces are collapsed in one iteration, thereby the algorithm can rapidly generate high-quality approximations of polygonal models with minimal times of collapses than Garland's and Pan's algorithms. The experiment results demonstrate the efficiency of the new algorithm.
RKPianGraphSort: a graph based sorting algorithm
Authors: Rajat K. Pal
Venue: Ubiquity (2007)

Sorting is a well-known problem frequently used in many aspects of the world of computational applications. Sorting means arranging a set of records (or a list of keys) in some (increasing or decreasing) order. In this paper, we propose a graph based comparison sorting algorithm, designated as RKPianGraphSort, that takes time Θ(n2) in the worst-case, where n is the number of records in the given list to be sorted.
Models for Dynamic Load Balancing in a Heterogeneous Multiple Processor System
Authors: Yuan-Chieh Chow
Venue: IEEE Transactions on Computers (1979)

Queueing models for a simple heterogeneous multiple processor system are presented, analyzed, and compared. Each model is distinguished by a job routing strategy which is designed to reduce the average job turnaround time by balancing the total load among the processors. In each case an arriving job is routed by a job dispatcher to one of m parallel processors. The job routing strategies are divided into two classes: deterministic and nondeterministic. The nondeterministic policies are described by state independent branching probabilities. For the deterministic policies, the next processor is chosen to minimize or maximize the expected value of a performance related criterion function.
Superquadrics and Angle-Preserving Transformations
Authors: A. H. Barr
Venue: IEEE Computer Graphics and Applications (1981)

A new and powerful family of parametric shapes extends the basic quadric surfaces and solids, yielding a variety of useful forms.
Studying the Nedap/Groenendaal ES3B voting computer: a computer security perspective
Authors: Rop Gonggrijp, Willem-Jan Hengeveld
Venue: Proceedings of the USENIX Workshop on Accurate Electronic Voting Technology (2007)

The Nedap/Groenendaal ES3B voting computer is being used by 90% of the Dutch voters. With very minor modifications, the same computer is also being used in parts of Germany and France. In Ireland the use of this machine is currently on hold after significant doubts were raised concerning its suitability for elections. This paper details how we installed new software in Nedap ES3B voting computers. It details how anyone, when given brief access to the devices at any time before the election, can gain complete and virtually undetectable control over the election results. It also shows how radio emanations from an unmodified ES3B can be received at several meters distance and used to tell what is being voted. We conclude that the Nedap ES3B is unsuitable for use in elections, that the Dutch regulatory framework surrounding e-voting currently insufficiently addresses security, and we pose that not enough thought has been given to the trust relationships and verifiability issues inherent to DRE class voting machines.
Performance Adjustment of an APL Interpreter
Authors: M. Maekawa
Venue: IEEE Transactions on Software Engineering (1982)

An APL interpreter is analyzed to examine how microprogramming can improve its performance. Also examined is how the modularization method or program structure affects performance improvement. Two basic modularization methods, function and data modularizations, are investigated. We rind that the performance gain may reach 100-time speed-up and that a proper selection of modules is very important to obtain the maximum performance gain under a limited microprogram memory. We also find that both the function and the data modularizations provide the same degree of performance improvement despite the finding that they tend to affect the complementary parts of a program.
A replication process of metallic micro-mold by using parylene embossing and electroplating
Authors: Sung-Won Youn, Hiroshi Goto, Masaharu Takahashi, Shoji Oyama, Yasuhiko Oshinomi, Kinya Matsutani, Ryutaro Maeda
Venue: Microelectronic Engineering (2008)

This study demonstrated a replication process for metallic micro-mold that combines the parylene-C (poly-chloro-p-xylylene C) hot-embossing and electroplating techniques. A nickel original master was fabricated using the deep RIE silicon etching followed by the electroplating process. Then, the patterned fields composed of arrays of 25@mm-high, 10@mm-wide and 1mm-long lines with 10@mm spacing in nickel molds were successfully replicated on the 60@mm-thick parylene-C films by the hot-emboss process. Under complete filling conditions, the deviation of the replicated micropattern was less than 2.4%. The electroplated copper successfully filled parylene-C replica master patterns with the aspect ratio of 2.5 without the void formation by both adding organic addictives and controlling the seed layer thickness. After electroplating, the copper micro-mold could be successfully separated from the parylene-C replica master.
An EAI Pattern-Based Comparison of Spaces and Messaging
Authors: Daniel Martin, Daniel Wutke, Thorsten Scheibler, Frank Leymann
Venue: Proceedings of the 11th IEEE International Enterprise Distributed Object Computing Conference (2007)

Enterprise Application Integration (EAI) is a major chal- lenge for enterprises to ensure optimal utilization of their landscape of diverse applications. Enterprise Application Integration Patterns help to ease this problem by describing recurring EAI problems and proposing possible solutions. As of today, Message-oriented Middleware (MOM) is state- of-the-art for EAI integration middleware infrastructures. However, Space-based computing (SBC) has been found to offer essentially the same qualities as MOM in terms of asynchronous, reliable and loosely coupled communication and might therefore provide a suitable alternative to MOM in the field of EAI. The objective of this paper is to pro- vide a comparison of MOM and SBC from an application's point of view through an in-depth analysis of EAI patterns, assuming SBC instead of MOM as their underlying middle- ware.
A Web Collaborative Learning System Based on Multi-agent
Authors: Zhengyou Wang, Jianhua Ming
Venue: Proceedings of the Third International Conference on Natural Computation - Volume 05 (2007)

On the basis of concept, characteristics and related work of collaborative learning, this paper proposes a practical and efficient way based on multi-agent technology. At first, the paper introduces a collaborative learning framework which supporting group learning and illustrated the whole learning process. Secondly, the paper presents some key issues to implementation of the virtual learning environment, such as intelligent grouping, intelligent question & answer system, knowledge management, evaluation of group-learning effectiveness. Learning practice verifies the validity of the system.
Adapting an open-source web-based assessment system for the automated assessment of programming problems
Authors: Olly Gotel, Christelle Scharff
Venue: Proceedings of the sixth conference on IASTED International Conference Web-Based Education - Volume 2 (2007)

This paper describes the adaptation of an open-source web-based assessment system to support the teaching and assessment of programming fundamentals. WeBWorK is a system that has been used effectively in mathematics for a number of years and the nature of its underlying engine makes it particularly well-suited to the problems from this discipline. It is accessible for instructors to contribute problems and free for students to use. A community has built up around WeBWorK to share problem sets in mathematics. Within computer science, many of the web-based programming delivery and assessment systems are commercial initiatives; students pay to use them and problem sets are administered centrally. This paper describes a project that is adapting WeBWorK for use in computer science and presents initial findings from its use over one academic year. Our on-going and future work is summarized, and the broader potential highlighted.
A Gestalt theoretic perspective on the user experience of location-based services
Authors: Jeni Paay, Jesper Kjeldskov
Venue: Proceedings of the 19th Australasian conference on Computer-Human Interaction: Entertaining User Interfaces (2007)

Location-based services provide mobile users with information and functionality tailored to their geographical location. Within recent years these kinds of context-aware mobile systems have received increasing attention from software industry as well as from researchers within a wide range of computing disciplines. However, while a lot of research has been done into sensing, adapting and philosophizing over the complex concept of "context", little theoretically based knowledge exists about why, from a user experience perspective, some context-aware system designs work well and why others don't. Contributing to this discussion, this paper suggests the perspective of "Gestalt theory" as a potential theoretical framework for understanding the use of this class of computer systems, and argues that describing the user experience of location-based services through Gestalt theory's principles of proximity, closure, symmetry, continuity, and similarity can help explain how people make sense of small and fragmented pieces of information on mobile devices in context.
A Fast and Stable Algorithm for Obstacle-Avoiding Rectilinear Steiner Minimal Tree Construction
Authors: Pei-Ci Wu, Jhih-Rong Gao, Ting-Chi Wang
Venue: Proceedings of the 2007 Asia and South Pacific Design Automation Conference (2007)

In routing, finding a rectilinear Steiner minimal tree (RSMT) is a fundamental problem. Today's design often contains rectilinear obstacles, like macro cells, IP blocks, and pre-routed nets. Therefore obstacle-avoiding RSMT (OARSMT) construction becomes a very practical problem. In this paper we present a fast and stable algorithm for this problem. We use a partitioning based method and an ant colony optimization based method to construct obstacle-avoiding Steiner minimal tree (OASMT). Besides, two heuristics are proposed to do the rectilinearization and refinement to further improve wirelegnth. The experimental results show our algorithm achieves the best wirelength results in most of the test cases and the runtime is very small even for the larger cases each of which has both the number of terminals and the number of obstacles more than 100.
Weighted order statistic and fuzzy rules CFAR detector for Weibull clutter
Authors: Amir Zaimbashi, Mohammad Reza Taban, Mohammad Mehdi Nayebi, Yaser Norouzi
Venue: Signal Processing (2008)

Order statistic (OS) CFAR processor is a powerful detector, but similar to many other CFAR detectors, suffers from clutter edge as well as interfering targets. To overcome these problems, two derivations of this detector have been developed. These are order statistic greatest of (OSGO) and order statistic smallest of (OSSO) CFAR processors. The cost, paid for this improvement, is a considerable decrease in detection probability for homogenous Weibull clutter. Furthermore, a substantial performance degradation of OSGO in interfering target (high target masking effect) and an excessive false alarm of OSSO in clutter edge, also, occur. This behavior is a result of non-soft rules used in these two detectors. This paper proposes a weighted order statistic and fuzzy rules-CFAR detector, which employs some soft rules based on fuzzy logic to cure the mentioned problems. Our simulation results demonstrate that considering realistic Weibull clutter, the proposed detector gives better detection probability than that of OSGO and OSSO detectors. Moreover, considering the problems of clutter edge and interfering target, the performance of the method is comparable to the best performance of the OSGO and OSSO detectors in different conditions.
Reputation Systems for Fighting Pollution in Peer-to-Peer File Sharing Systems
Authors: Cristiano Costa, Jussara Almeida
Venue: Proceedings of the Seventh IEEE International Conference on Peer-to-Peer Computing (2007)

Content pollution is a de facto problem in several currently popular Peer-to-Peer file sharing systems. Previously proposed strategies to fight content pollution include a peer reputation system named Scrubber as well as the alternative Credence object reputation system. This paper builds on previous work into three directions. First, it evaluates the cost-effectiveness of Scrubber and Credence in reducing pollution dissemination when polluters make use of collusion and Sybil attacks. Second, it modifies the Scrubber system to increase its effectiveness, in particular under collusion. Finally, it proposes a hybrid peer and object reputation system that combines the benefits of both strategies. We performed an extensive evaluation of all three systems, for various configurations and pollution mechanisms, as well as collusion and Sybil attacks. Our results show that the new hybrid system is much more effective and robust to malicious actions than any individual strategy, even in very uncooperative and unreliable peer communities.
A Grid-based Spatial Association Mining Method
Authors: Xiaohui Zhao, Yu Fang
Venue: Proceedings of the Sixth International Conference on Grid and Cooperative Computing (2007)

The Grid is a distributed computing infrastructure that supports the sharing and coordinated use of various resources in virtual organizations. The Grid can be used for compute intensive tasks and data intensive applications. Data mining algorithms are intensive compute and data, and spatial data are heterogeneous, multidimensional and stored at various places. Therefore, the Grid can provide a computing and data management platform for spatial data. In this paper, a Grid-based spatial association mining method, Grid-based spatial Apriori algorithm (GSAA), is presented to find hidden relations and regularities in the grid framework. The main thoughts of GSAA are described. We adopt GSAA in a traffic information system. It discovers the inherent connections and relative factors, and finds the causes of traffic accidents and the places where the traffic accidents often take place. It proves to improve the traffic conditions of cities in the grid framework effectively.
Inquiry to the Effectiveness of Genetic Algorithms for Accurate Global Optimization of Continuous Functions
Authors: Xiaoping Zheng, Xinwei Ding
Venue: Proceedings of the Third International Conference on Natural Computation - Volume 04 (2007)

For a given precision of optimization, whether and how fast an algorithm achieves it can be used as a testing standard of performance. Compared with the search efficiency of random sampling, the performance of conventional binary coded genetic algorithm (GA) used for accurate global optimization is tested in this paper. It is found that the efficiency of GA in exploration and exploitation is not even better than that of random sampling because of simultaneous operation of these two processes. The Hamming cliff which may occur in the binary coded genetic algorithms is difficult to be bridged by conventional crossover strategies. The accuracy of solution obtained by GA through limited generations of evolution can not be well assured and evaluated. Based on the results, the strategies to improve the performance of GA are suggested.
A Petri Net Model for Evaluating Packet Buffering Strategies in a Network Processor
Authors: Girish B.C., R. Govindarajan
Venue: Proceedings of the Fourth International Conference on Quantitative Evaluation of Systems (2007)

Previous studies have shown that buffering packets in DRAM is a performance bottleneck. In order to understand the impediments in accessing the DRAM, we developed a detailed Petri net model of IP forwarding application on IXP2400 that models the different levels of the memory hierarchy. The cell based interface used to receive and transmit packets in a network processor, leads to some small size DRAM accesses. Such narrow accesses to the DRAM expose the bank access latency, reducing the bandwidth that can be realized. With real traces up to 30% of the accesses are smaller than the cell size, resulting in 7.7% reduction in DRAM bandwidth. To overcome this problem, we propose buffering these small chunks of data in the on chip scratchpad memory. This scheme also exploits greater degree of parallelism between different levels of the memory hierarchy. Using real traces from the internet, we show that the transmit rate can be improved by an average of 21% over the base scheme without the use of additional hardware. Further, the impact of different traffic patterns on the network processor resources is studied. Under real traffic conditions, we show that the data bus which connects the off-chip packet buffer to the microengines, is the obstacle in achieving higher throughput.
Perturbation-based Fault Screening
Authors: Paul Racunas, Kypros Constantinides, Srilatha Manne, Shubhendu S. Mukherjee
Venue: Proceedings of the 2007 IEEE 13th International Symposium on High Performance Computer Architecture (2007)

Fault screeners are a new breed of fault identification technique that can probabilistically detect if a transient fault has affected the state of a processor. We demonstrate that fault screeners function because of two key characteristics. First, we show that much of the intermediate data generated by a program inherently falls within certain consistent bounds. Second, we observe that these bounds are often violated by the introduction of a fault. Thus, fault screeners can identify faults by directly watching for any data inconsistencies arising in an application's behavior. We present an idealized algorithm capable of identifying over 85% of injected faults on the SpecInt suite and over 75% overall. Further, in a realistic implementation on a simulated Pentium-III-like processor, about half of the errors due to injected faults are identified while still in speculative state. Errors detected this early can be eliminated by a pipeline flush. In this paper, we present several hardware-based versions of this screening algorithm and show that flushing the pipeline every time the hardware screener triggers reduces overall performance by less than 1%