ppxscal/embedding_network huggingface dataset:
Line/Polygon Classification: A Study of the Complexity of Geometric Computation
Authors: R. B. Tilove
Venue: IEEE Computer Graphics and Applications (1981)

Illuminating the techniques of computational geometry, an analysis of two LPC algorithms compares their efficiency for handling polygon-clipping problems.
Concurrency with Erlang
Authors: Steve Vinoski
Venue: IEEE Internet Computing (2007)

Have you ever devised what you thought was a good solution to a really difficult problem, only to find that the answer would've been almost trivial with a different tool or approach? One of the primary reasons concurrency is so hard is that popular imperative programming languages such as Java and C++ essentially require state to be shared among threads. With multiple threads running on multiple CPUs, more than one program pathway can be active simultaneously, and without the appropriate safeguards in place, the threads can read partial values and overwrite each other's data, resulting in bogus values and application instability. One way to avoid the problems with shared state is to simply avoid it, but that's impractical in a language like C++ or Java. A better way to avoid shared state is to switch to a programming language specifically designed to do exactly that. Erlang is one such language.
Children's navigation of hyperspace: are spatial skills important?
Authors: S. Jones, G. E. Burnett
Venue: Proceedings of the sixth conference on IASTED International Conference Web-Based Education - Volume 2 (2007)

Hypertext is becoming increasingly popular as a platform for educational material, allowing the user autonomy and flexibility in choosing a route through the presented information. However, the required decision-making process places extra cognitive demands on the user, and this may result in disorientation and the phenomenon known as "lost in hyperspace". Individuals with high spatial ability appear to demonstrate superior navigational skills within hypertext, completing tasks more quickly and with fewer errors then those with low spatial ability. They tend to form more accurate internal representations, or cognitive maps, of hypertext systems that correspond better to the underlying physical structure. Little research has been carried out with children to assess their formation of cognitive maps of hyperspace. In this study, 32 children aged 10-11 years from a primary school in the UK were given search tasks to complete on an environmental Web site. Various measures were made of their navigational efficiency, their degree of lostness, and their ability to complete a map of the routes they had traversed. Those with high spatial ability completed the tasks in shorter time, became lost less frequently, and completed the maps more accurately. This paper discusses the implications of these results to the success of hypertext learning environments for learners with low spatial ability.
Path Planning Algorithm for Mobile Robot Based on Path Grids Encoding Novel Mechanism
Authors: Han-dong Zhang, Bao-hua Dong, Yu-wan Cen, Rui Zheng, Shuji Hashimoto, Ryo Saegusa
Venue: Proceedings of the Third International Conference on Natural Computation - Volume 04 (2007)

Novel fixed-length decimal encoding mechanism is proposed, which is for techniques of path planning of mobile robot based on an improved genetic algorithm. Effective path grids are adopted to identify the robot's motion surrounding. The obstacles can be described as polygons based on the given grids. The only vertexes of every obstacles polygon have corresponding unique decimal series value by the intersection of the grids. Then the planning paths of the mobile robot are encoded into decimal encode string, which equals to the sum of the numbers of all effective vertexes of polygons in path grids. In the chromosome, the decimal value of each nonzero bit is the code of vertex about corresponding obstacle for the path planning. The sequence of vertexes in a chromosome is that in the planning path. Such an encoding manner has the excellent adaptation for fixed-length decimal encoding mechanism; it also easily overcomes the trap of obstacles in path planning algorithm. The algorithm makes the path planning more simple and effective, and speeds up convergent speed of the algorithm. Numerical simulation to the problem shows the efficiency of the proposed algorithm.
Scheduling Algorithms for I/O Blockings with a Multi-frame Task Model
Authors: Shan Ding, Hiroyuki Tomiyama, Hiroaki Takada
Venue: Proceedings of the 13th IEEE International Conference on Embedded and Real-Time Computing Systems and Applications (2007)

A task that suspends itself to wait for an I/O completion or to wait for an event from another node in distributed environments is called an I/O blocking task. In conventional hard real-time scheduling theories, there exist several approaches to schedule such I/O blocking tasks within the conventional framework of rate monotonic analysis (RMA). However, most of them are pessimistic. In this paper, we propose effective algorithms that can schedule a task set which includes I/O blocking tasks under dynamic priority assignment. We present a new critical instant theorem for multi-frame task set under dynamic priority assignment. The schedulability is analyzed under the new critical instant theorem. For the schedulability analysis , this paper presents saturation summation which is used to calculate maximum interference function (MIF). With the saturation summation, the schedulability of a task set including I/O blocking tasks can be analyzed more accurately. We propose an algorithm which is based on a Frame Laxity Monotonic Scheduling (FLMS). Genetic algorithm is also applied. From our experiments, we can conclude that the FLMS can significantly reduce the time of the calculation time, and GA can improve task schedulability ratio than the FLMS.
Putting more genetics into genetic algorithms
Authors: Donald S. Burke, Kenneth A. De Jong, John J. Grefenstette, Connie Loggia Ramsey, Annie S. Wu
Venue: Evolutionary Computation (1998)

The majority of current genetic algorithms (GAs), while inspired by natural evolutionary systems, are seldom viewed as biologically plausible models. This is not a criticism of GAs, but rather a reflection of choices made regarding the level of abstraction at which biological mechanisms are modeled, and a reflection of the more engineering-oriented goals of the evolutionary computation community. Understanding better and reducing this gap between GAs and genetics has been a central issue in an interdisciplinary project whose goal is to build GA-based computational models of viral evolution. The result is a system called Virtual Virus (VIV). VIV incorporates a number of more biologically plausible mechanisms, including a more flexible genotype-to-phenotype mapping. In VIV the genes are independent of position, and genomes can vary in length and may contain noncoding regions, as well as duplicative or competing genes. Initial computational studies with VIV have already revealed several emergent phenomena of both biological and computational interest. In the absence of any penalty based on genome length, VIV develops individuals with long genomes and also performs more poorly (from a problem-solving viewpoint) than when a length penalty is used. With a fixed linear length penalty, genome length tends to increase dramatically in the early phases of evolution and then decrease to a level based on the mutation rate. The plateau genome length (i.e., the average length of individuals in the final population) generally increases in response to an increase in the base mutation rate. When VIV converges, there tend to be many copies of good alternative genes within the individuals. We observed many instances of switching between active and inactive genes during the entire evolutionary process. These observations support the conclusion that noncoding regions serve as scratch space in which VIV can explore alternative gene values. These results represent a positive step in understanding how GAs might exploit more of the power and flexibility of biological evolution while simultaneously providing better tools for understanding evolving biological systems.
Improved Time and Parallel Processor Bounds for Fortran-Like Loops
Authors: R. W. Heuft
Venue: IEEE Transactions on Computers (1982)

Dynamic characteristics of program execution must be studied in order to calculate meaningful time and parallel processor bounds. The paper entitled "Time and Parallel Processor Bounds for Fortran-Like Loops" [1] studies only the static interaction between statements within a program to arrive at these bounds. Consequently, very loose bounds are obtained for certain programs. Improved estimates of time and processor bounds are provided for two of the example programs presented in the above-mentioned paper. These estimates are based on an expression of the relationship between operations which calculate values and operations which later use those values as operands.
K-Nearest Oracle for Dynamic Ensemble Selection
Authors: A. H. -R. Ko, R. Sabourin, A. Britto Jr.
Venue: Proceedings of the Ninth International Conference on Document Analysis and Recognition - Volume 01 (2007)

For handwritten pattern recognition, multiple classifier system has been shown to be useful in improving recognition rates. One of the most important issues to optimize a mul- tiple classifier system is to select a group of adequate clas- sifiers, known as Ensemble of Classifiers (EoC), from a pool of classifiers. Static selection schemes select an EoC for all test patterns, and dynamic selection schemes select different classifiers for different test patterns. Nevertheless, it has been shown that traditional dynamic selection does not give bet- ter performance than static selection. We propose four new dynamic selection schemes which explore the property of the oracle concept. The result suggests that the proposed schemes are apparently better than the static selection using the major- ity voting rule for combining classifiers.
Capacity analysis of MIMO MRC systems in correlated rayleigh fading environments
Authors: Xianyi Rui, Ronghong Jin, Junping Geng
Venue: Wireless Personal Communications: An International Journal (2007)

In this paper, we analyze the capacity of multiple-input multiple-output systems employing maximal ratio combining under Rayleigh fading environments in the presence of spatial fading correlation at the transmitter or receiver. Based on statistical properties of the largest eigenvalue of correlated complex Wishart matrices, the exact closed-form expressions for the cumulative distribution function and the probability density function of the output signal-to-noise ratio are presented. The results are used to analyze the outage and ergodic capacities of the systems. The analysis shows that ergodic capacity improves with the increase of the channel correlation coefficient and the analytical results are validated by Monte Carlo simulations.
Author Index - HPDC-14
Venue: Proceedings of the High Performance Distributed Computing, 2005. HPDC-14. Proceedings. 14th IEEE International Symposium (2005)

With the increasing cost of providing computing and storage facilities for research capability, it has become important that universities make increasingly efficient use of their existing resources. The strategy developed at the University of Bristol has involved the design and construction of a campus grid. This has enabled better utilization of spare capacity on available systems connected to the grid and also the separation, for the first time, of those applications that require parallel compute resources (i.e. closely coupled systems) and those that require serial resources. The overall implementation of this strategy was driven by two prime considerations. Firstly, the contributing cluster systems are, in the main, very heavily used and connecting them onto the grid must be done in a non-invasive way to ensure currently executing applications don't have to be interrupted or any other cluster operations compromised. Secondly, the grid has been considered by many scientific users to be over hyped. This implied that we needed to get a system up and running quickly however 'simple' it was to prove the concept was viable. It was hoped that involving real users at an early stage of the grid's construction would lead to them evangelising about the system and thus, encourage more users to use the system. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Realization of Fault-Tolerant Machines Linear Code Application
Authors: A. Sengupta
Venue: IEEE Transactions on Computers (1981)

This correspondence deals with the fault-tolerant realization of a sequential machine using error-correcting (n,k) linear codes. Earlier works in the same area confine their attention to modified Reed-Muller Code and perfect Hamming Code and achieve the realization using a number of majority logic gates, which makes the entire realization quite complex. The realization discussed in this paper needs a smaller number of circuit components with less complexity.
The Politics of DDoS Attacks
Authors: Greg Goth
Venue: IEEE Distributed Systems Online (2007)

News about distributed-denial-of-service attacks on Estonian government Web sites might have represented more smoke than fire, but it also revealed a new political battlefield. Networking veterans say public officials' accusations can make ad hoc "hacktivism" seem like a state-sponsored attack. When you add porous network defenses and a credulous media, you've got the potential for a real problem.
A posteriori error estimation and basis adaptivity for reduced-basis approximation of nonaffine-parametrized linear elliptic partial differential equations
Authors: N. C. Nguyen
Venue: Journal of Computational Physics (2007)

In this paper, we extend the earlier work [M. Barrault, Y. Maday, N. C. Nguyen, A.T. Patera, An ''empirical interpolation'' method: application to efficient reduced-basis discretization of partial differential equations, C.R. Acad. Sci. Paris, Serie I 339 (2004) 667-672; M.A. Grepl, Y. Maday, N.C. Nguyen, A.T. Patera, Efficient reduced-basis treatment of nonaffine and nonlinear partial differential equations, M2AN Math. Model. Numer. Anal. 41 (3) (2007) 575-605.] to provide a posteriori error estimation and basis adaptivity for reduced-basis approximation of linear elliptic partial differential equations with nonaffine parameter dependence. The essential components are (i) rapidly convergent reduced-basis approximations - (Galerkin) projection onto a space W"N^u spanned by N global hierarchical basis functions which are constructed from solutions of the governing partial differential equation at judiciously selected points in parameter space; (ii) stable and inexpensive interpolation procedures - methods which allow us to replace nonaffine parameter functions with a coefficient-function expansion as a sum of M products of parameter-dependent coefficients and parameter-independent functions; (iii) a posteriori error estimation - relaxations of the error-residual equation that provide inexpensive yet sharp error bounds for the error in the outputs of interest; (iv) optimal basis construction - processes which make use of the error bounds as an inexpensive surrogate for the expensive true error to explore the parameter space in the quest for an optimal sampling set; and (v) offline/online computational procedures - methods which decouple the generation and projection stages of the approximation process. The operation count for the online stage - in which, given a new parameter value, we calculate the output of interest and associated error bounds - depends only on N, M, and the affine parametric complexity of the problem; the method is thus ideally suited for repeated and reliable evaluation of input-output relationships in the many-query or real-time contexts.
New and improved architectures for Montgomery modular multiplication
Authors: M. Sudhakar, R. V. Kamala, M. B. Srinivas
Venue: Mobile Networks and Applications (2007)

In this paper an improved Montgomery multiplier, based on modified four-to-two carry-save adders (CSAs) to reduce critical path delay, is presented. Instead of implementing four-to-two CSA using two levels of carry-save logic, authors propose a modified four-to-two CSA using only one level of carry-save logic taking advantage of pre-computed input values. Also, a new bit-sliced, unified and scalable Montgomery multiplier architecture, applicable for both RSA and ECC (Elliptic Curve Cryptography), is proposed. In the existing word-based scalable multiplier architectures, some processing elements (PEs) do not perform useful computation during the last pipeline cycle when the precision is not equal to an exact multiple of the word size, like in ECC. This intrinsic limitation requires a few extra clock cycles to operate on operand lengths which are not powers of 2. The proposed architecture eliminates the need for extra clock cycles by reconfiguring the design at bit-level and hence can operate on any operand length, limited only by memory and control constraints. It requires 2∼15% fewer clock cycles than the existing architectures for key lengths of interest in RSA and 11∼18% for binary fields and 10∼14% for prime fields in case of ECC. An FPGA implementation of the proposed architecture shows that it can perform 1,024-bit modular exponentiation in about 15 ms which is better than that by the existing multiplier architectures.
Beamauth: two-factor web authentication with a bookmark
Authors: Ben Adida
Venue: Proceedings of the 14th ACM conference on Computer and communications security (2007)

We propose BeamAuth, a two-factor web authentication technique where the second factor is a specially crafted bookmark. BeamAuth presents two interesting features: (1) only server-side deployment is required alongside any modern, out-of-the-box web browser on the client side, and (2) credentials remain safe against many types of phishing attacks, even if the user fails to check proper user interface indicators. BeamAuth is deployable immediately by any login-protected web server with only minimal work, and it neither weakens nor interferes with other anti-phishing techniques. We believe BeamAuth may be most useful in preventing a number of phishing attacks at high-value single sign-on sites, e.g. OpenID providers.
Independent component analysis in the blind watermarking of digital images
Authors: J. J. Murillo-Fuentes
Venue: Neurocomputing (2007)

We propose a new method for the blind robust watermarking of digital images based on independent component analysis (ICA). We apply ICA to compute some statistically independent transform coefficients where we embed the watermark. The main advantages of this approach are twofold. On the one hand, each user can define its own ICA-based transformation. These transformations behave as ''private-keys'' of the method. On the other hand, we will show that some of these transform coefficients have white noise-like spectral properties. We develop an orthogonal watermark to blindly detect it with a simple matched filter. We also address some relevant issues as the perceptual masking of the watermark and the estimation of the detection probability. Finally, some experiments have been included to illustrate the robustness of the method to common attacks and to compare its performance to other transform domain watermarking algorithms.
A Virus Immunization Model Based on Communities in Large Scale Networks
Authors: Jianhua Sun, Jizha Qin, Shu Chen, Hao Chen, Dingding Li
Venue: Proceedings of the Eighth ACIS International Conference on Software Engineering, Artificial Intelligence, Networking, and Parallel/Distributed Computing - Volume 03 (2007)

With the development of computers and Internet, more and more people use email. Viruses of email have caused large damages. Traditional intentional immunization based on nodes degree does not take the positions of infected nodes into account, and protects the nodes which have high degree. We introduce the concept of community into the research field of virus and immunization, and propose an immunization model based on communities. According to the different stages of virus infection, this model immunizes infected communities or healthy communities, which slows down the virus spreading rate and keeps virus from spreading to more communities. Degree immunization can not keep the virus in a part of communities, and as a result the infected nodes diffuse in almost all communities. Communities immunization can keep the virus in a certain number of communities. These two models are different in the ratio of infected communities and infected communities vector. In summary, communities immunization is different from the degree immunization completely, and is a novel and effective scheme.
Timelines of creativity: A study of intellectual innovators in information science
Authors: Blaise Cronin, Lokman I. Meho
Venue: Journal of the American Society for Information Science and Technology (2007)

We explore the relationship between creativity and both chronological and professional age in information science using a novel bibliometric approach that allows us to capture the shape of a scholar's career. Our approach draws on D.W. Galenson's (2006) analyses of artistic creativity, notably his distinction between conceptual and experimental innovation, and also H.C. Lehman's (1953) seminal study of the relationship between stage of career and outstanding performance. The data presented here suggest that creativity is expressed in different ways, at different times, and with different intensities in academic information science. &copy; 2007 Wiley Periodicals, Inc.
The contribution of critical IS research
Authors: Bernd Carsten Stahl, Carole Brooke
Venue: Communications of the ACM (2008)

Solving ongoing external problems may require looking inward first.
Exploiting open-source projects to study software design
Authors: Christopher P. Fuhrman
Venue: Informatics in education (2007)

This article presents an approach to using open-source tools and open-source projects to add realistic and practical examples to a course on software design in a professional master's program of software engineering. Students are encouraged to use object-oriented, open-source software projects available on the Internet, and to analyze their design attributes using open-source tools, to hopefully improve their designs using documented design patterns and other design strategies. The proposed approach provides a variety of realistic examples for study, which can vary from semester to semester, without the instructor having to prepare complicated realistic examples or to rely on over-simplified examples in textbooks. Because the course and the approach are relatively new, a quantifiable assessment of the pedagogical approach has not been presented. However, the argument is made that realistic examples provide for better learning, and evidence is provided to show the feasibility of the approach. The instructor's role is more of a mentor than a traditional teacher, as every open-source project is different from a design perspective.
A Cheating Detection Mechanism based on Fuzzy Reputation Management of P2P MMOGs
Authors: Xiang-bin Shi, Liu Fang, Du Ling, Chen Xiao-hong, Xing Yuan-sheng
Venue: Proceedings of the Eighth ACIS International Conference on Software Engineering, Artificial Intelligence, Networking, and Parallel/Distributed Computing - Volume 02 (2007)

The false decision ratio in MMOGs is quite high because of the fixed parameter thresholds deployed in the cheating detection mechanism. This paper introduces the trust management into the cheating detection mechanism, and proposes a FuzzyTD algorithm. The algorithm updates player's reputation vector calculated from his history data of the game, and then adjusts the game parameter thresholds further. Therefore, the false decision ratio reduces. The simulation results show that the false decision ratio is much lower, and the performance is much better by introducing the FuzzyTD algorithm.