ppxscal/embedding_network huggingface dataset:
A parallel and randomized algorithm for large-scale discrete dual-Vt assignment and continuous gate sizing
Authors: Tai-Hsuan Wu, Lin Xie, Azadeh Davoodi
Venue: Proceeding of the 13th international symposium on Low power electronics and design (2008)

We propose a parallel and randomized algorithm to solve the problem of discrete dual-Vt assignment combined with continuous gate sizing which is an important low power design technique in high performance domains. This combinatorial optimization problem is particularly difficult to solve on large-sized circuits. We first introduce a hybrid algorithm which combines the existing heuristics and convex formulations for this problem to achieve a better tradeoff between the runtime of the algorithm and the quality of generated solution. We then extend our algorithm to include parallelism and randomization. We introduce a unique utilization of parallelism to better identify the optimization direction. Consequently, we can reduce both the number of iterations in optimization as well as improve the quality of solution. We further use random sampling to avoid being trapped in local minima and to focus the optimization effort on the more "promising" regions of the solution space. Our algorithm improves the average power by 37% compared to an approach which is based on solving a continuous convex program and applying discretization. Power improvement is over 50% for larger benchmarks for an implementation on a grid of 9 computers.
Bounds on the cover time
Authors: A. Z. Broder, A. R. Karlin
Venue: Proceedings of the 29th Annual Symposium on Foundations of Computer Science (1988)

A particle that moves on a connected unidirected graph G with n vertices is considered. At each step the particle goes from the current vertex to one of its neighbors, chosen uniformly at random. The cover time is the first time when the particle has visited all the vertices in the graph, starting from a given vertex. Upper and lower bounds are presented that relate the expected cover time for a graph to the eigenvalues of the Markov chain that describes the above random walk. An interesting consequence is that regular expander graphs have expected cover time theta (n log n).
Performance analysis of an evolutionary algorithm for fault detection in t-diagnosable multi-processor systems
Authors: M. Elhadef, L. B. Romdhane, B. Ayeb
Venue: International Journal of Parallel, Emergent and Distributed Systems (2007)

In this paper, we present a performance analysis of an evolutionary approach for fault identification in t-diagnosable systems, i.e. systems in which the set of t permanently faulty units could be unambiguously identified. The proposed algorithm is based on evolutionary/genetic computing and is shown to correctly identify the set of faulty units. Simulation results are more than encouraging and should stimulate future research.
A Primer for Real-Time Simulation of Large-Scale Networks
Authors: Jason Liu
Venue: Proceedings of the 41st Annual Simulation Symposium (anss-41 2008) (2008)

Real-time network simulation refers to simulating computer networks in real time so that the virtual network can interact with real implementations of network protocols, network services, and distributed applications. In this paper, we present the motivation behind real-time network simulation and compare it against other major networking research tools, including analytical models, physical testbeds, simulation, and emulation. We introduce PRIME, a parallel real-time network simulator, and provide a summary of techniques that allow PRIME to model large-scale networks and interact with many real applications under the real-time constraint. We also discuss ongoing research efforts that will allow real-time network simulation to assume important roles at supporting future networking research.
A Model for Dynamic Integration of Ontologies in P2P/DAKS Coalitions
Authors: S. M. Deen, K. Ponnamperuma, M. Takizawa
Venue: Proceedings of the 22nd International Conference on Advanced Information Networking and Applications (2008)

The paper presents a model for the dynamic integration of global ontologies from peer ontologies in peer to peer data and knowledge sharing (P2P/DAKS) networks, and demonstrates its effectiveness. The peer ontologies from peer schemas (possibly heterogeneous) have to be created within some rules, as discussed. The integration is carried out with the help of a graph based inclusion algorithm to determine the semantic closeness of inter-ontology concepts. The effectiveness of the model is demonstrated by comparing its results with those of a WordNet-based approach.
An Interactive Fire Animation on a Mobile Environment
Authors: DongGyu Park, SangHyuk Woo, MiRiNa Jo, DoHoon Lee
Venue: Proceedings of the 2008 International Conference on Multimedia and Ubiquitous Engineering (2008)

In computer graphics, fluid-like motion is an important and challenging problem with many applications. Currently, the graphical performance and resolution of the mobile phone is highly improved; therefore, mobile 3D games are more and more popular items in the field of mobile services. Yet interactive physically-based fluid simulation is still challenging for mobile platforms. Stable and fast fluid simulation methods are well developed in PC and console games, but fluid simulation and interactive fluid models still have many problems in the mobile environment. We studied and implemented physically-based models for fluids like fire and smoke effects on a Mobile 3D environment.
Validating Secure Connections between Wireless Devices in Pervasive Computing Using Data Matrix
Authors: Seunghyun Im
Venue: Proceedings of the 2008 International Conference on Multimedia and Ubiquitous Engineering (2008)

This paper describes the techniques for establishing secure associations between mobile devices in pervasive computing where the communications are often established with minimal priori knowledge. An improved method for securing the association by comparing a hashed key using Data Matrix will be presented. A Data Matrix displayed or printed on another device in the association is captured with a built-in digital camera. The image is then used to validate the device's public key.
A Discussion Information-Structuring Model Based on the Toulmin Formalism
Authors: Caiquan Xiong, Ying Pan, Dehua Li
Venue: Proceedings of the First International Workshop on Knowledge Discovery and Data Mining (2008)

In the course of discussion, the group will produce a lot of discussion information, in which the consensus is hided. This paper proposes a discussion information-structuring model for consensus building. The model divided a statement into several parts such as premise, warrant, modality, claim etc., according to the Toulmin argument formalism. "Modelity" is designed as a quantitative scale that reflects the expert's attitude to the claim, while premise and warrant are used to provide demonstration for the expert views. We can reach a consensus by computing the value of modality. The model is a comprehensive description of the discussion information, and can effectively manage the discussion information and do consensus building.
Mining usage expertise from version archives
Authors: David Schuler, Thomas Zimmermann
Venue: Proceedings of the 2008 international working conference on Mining software repositories (2008)

In software development, there is an increasing need to find and connect developers with relevant expertise. Existing expertise recommendation systems are mostly based on variations of the Line 10 Rule: developers who changed a file most often have the most implementation expertise. In this paper, we introduce the concept of usage expertise, which manifests itself whenever developers are using functionality, e.g., by calling API methods. We present preliminary results for the ECLIPSE project that demonstrate that our technique allows to recommend experts for files with no or little history, identify developers with similar expertise, and measure the usage of API methods.
A short note on singular values of optimal and superoptimal preconditioned matrices
Authors: Xiao-Qing Jin, Yi-Min Wei
Venue: International Journal of Computer Mathematics (2007)

In this short note, we prove that given any nonsingular matrix, the singular values of the superoptimal preconditioned matrix do not exceed the corresponding singular values of the optimal preconditioned matrix.
Fractal characteristic-based endpoint detection for whispered speech
Authors: Xueqin Chen, Heming Zhao
Venue: Proceedings of the 6th WSEAS International Conference on Signal, Speech and Image Processing (2006)

In this paper, a fractal based approach is proposed to detect endpoints in whispered speech. The underlying principle is based on the fact that whispered speech is sufficiently chaotic and thus can be analyzed using fractal theory. Due to the different scope of fractal dimensions of silence, noise and speech segment, speech/non-speech segment could be determined from that with a simple decision scheme. The results of experiments, which have been performed on two databases and different methods, show the efficiency of the proposed whispered speech segmentation algorithm.
Robust multiple description image coding over wireless networks based on wavelet tree coding, error resilient entropy coding, and error concealment
Authors: Daewon Song, Lei Cao, Chang Wen Chen
Venue: Journal of Visual Communication and Image Representation (2008)

In this paper, we propose an integrated robust multiple description coding (MDC) scheme for compressed still images over error-prone channels with both packet loss and random bit errors. Multiple descriptions are first generated independently by using multiple description scalar quantizer (MDSQ). To achieve an excellent error resilient capability for each description, multiple bitstreams are then generated based on wavelet trees along the spatial orientations. The spatial orientation trees in the wavelet domain are individually encoded using SPIHT. Error propagation is thus limited within each bitstreams. However, synchronization words are usually needed to avoid error propagation across multiple independent bitstreams. In order to maintain high compression efficiency robust synchronization, we adopt error resilient entropy coding (EREC) to re-organize these variable-length bitstreams into fixed-length data slots before multiplexing and transmission. Therefore, the synchronization of the start of each bitstream can be automatically obtained at the receiver. Finally, to alleviate the devastating image degradation resulted from errors in the beginning of the bitstreams, we propose an error concealment technique to both constrain the EREC/MDC decoding and post-process the decoded wavelet coefficients. With analysis and experimental results, we have demonstrated how each of these components has contributed to the overall robustness of the proposed transmission of compressed images over wireless channels.
TCP Connection Scheduler in Single IP Address Cluster
Authors: Hajime Fujita, Hiroya Matsuba, Yutaka Ishikawa
Venue: Proceedings of the 2008 Eighth IEEE International Symposium on Cluster Computing and the Grid (2008)

A broadcast-based single IP cluster aims at being both scalable and available. However, existing systems can only employ static traffic assignment based on incoming packets. In this paper we propose FTCS, a newTCP connection dispatching mechanism that enables a single IP clusterto use more flexible load balancing algorithms. In this mechanism, one of the cluster nodes acts as a master node. A centralized connection scheduler runs on the master node in order to dispatch TCP connectionsto nodes of the clusters. Since connections are scheduled by asingle scheduler, the master node is able to employ arbitrary scheduling algorithms. Once a TCP connection is established on a node, succeeding communication is handled without involving the master node. When the master node fails, one of the nodes takes over the role of the master node. Therefore the master node does not becomea single point of failure. Benchmark results using SPECweb2005 Support benchmark show that a four-node Linux cluster using FTCS balances workloads well and successfully handles 13% more requests than the existing method, on average.
Geometric correction accuracy of different satellite sensor images: application of figure condition
Authors: E. Sertel, S. H. Kutoglu, S. Kaya
Venue: International Journal of Remote Sensing (2007)

In this study, the figure condition method was introduced to analyse the accuracy of geometric correction. Figure condition denotes the transformation ability of estimated model parameters for a given transformation model, and it can be used in a geometric correction procedure. To study the figure condition, multisensor satellite images were geometrically corrected using ground control points obtained by different methods. The accuracy of each geometric model was analysed by means of the root mean square error of unit weight and variance-covariance matrix of unknown parameters. Then, an error propagation law was applied to the geometric model in order to investigate the transformation ability of the model parameters and estimate error values of geometric correction for the whole image surface. The results of the research demonstrated that the figure condition can be applied to geometric correction, and error values of the whole study area can be obtained with this new approach without using check points.
C-TREND: Temporal Cluster Graphs for Identifying and Visualizing Trends in Multiattribute Transactional Data
Authors: Gediminas Adomavicius, Jesse Bockstedt
Venue: IEEE Transactions on Knowledge and Data Engineering (2008)

Organizations and firms are capturing increasingly more data about their customers, suppliers, competitors, and business environment. Most of this data is multi-attribute (multi-dimensional) and temporal in nature. Data mining and business intelligence techniques are often used to discover patterns in such data; however, mining temporal relationships typically is a complex task. We propose a new data analysis and visualization technique for representing trends in multi-attribute temporal data using a clustering-based approach. We introduce C-TREND, a system that implements the temporal cluster graph construct, which maps multi-attribute temporal data to a two-dimensional directed graph that identifies trends in dominant data types over time. In this paper, we present our temporal clustering-based technique, discuss its algorithmic implementation and performance, demonstrate applications of the technique by analyzing data on wireless networking technologies and baseball batting statistics, and introduce a set of metrics for further analysis of discovered trends.
USING A THEOREM PROVER FOR REASONING ON CONSTRAINT PROBLEMS
Authors: Marco Cadoli, Toni Mancini
Venue: Applied Artificial Intelligence (2007)

The efficiency of systems for constraint programming (CP) is currently highly affected by the actual formulation of the input problem. To this end, several choices have to be made by modelers in order to write efficient specifications and handle instances of realistic size, and this, of course, represents a major obstacle to reach full declarativeness. Several structural properties of problem specifications have been investigated in order to provide techniques that reformulate a constraint program into one which is more efficiently evaluable by the solver at hand. In this paper we consider two such properties, symmetries and functional dependencies among variables, and show that, by characterizing problem specifications as logical formulae, the task of deciding whether such properties hold, and consequently that of performing the relevant reformulations, can be practically mechanized by means of automated theorem proving (ATP) technology. In particular, we report the results on using ATP technology for checking the existence of symmetries, checking whether a given constraint is symmetry-breaking, and checking the existence of functional dependencies in a specification. The output of the reasoning phase is a transformed constraint program, consisting in a reformulated specification and, possibly, a search strategy. We show our techniques on problems such as graph coloring, Sailco inventory, and protein folding.
Discovering bucket orders from full rankings
Authors: Jianlin Feng, Qiong Fang, Wilfred Ng
Venue: Proceedings of the 2008 ACM SIGMOD international conference on Management of data (2008)

Discovering a bucket order B from a collection of possibly noisy full rankings is a fundamental problem that relates to various applications involving rankings. Informally, a bucket order is a total order that allows "ties" between items in a bucket. A bucket order B can be viewed as a "representative" that summarizes a given set of full rankings {T1, T2, ..., Tm}, or conversely B can be an "approximation" of some "ground truth" G where the rankings {T1, T2, ..., Tm} are simply the "linear extensions" of G. Current work of finding bucket orders such as the dynamic programming algorithm is mainly developed from the "representative" perspective, which maximizes items' intra-bucket similarity when forming a bucket. The underlying idea of maximizing intra-bucket similarity is realized via minimizing the sum of the deviations of median ranks within a bucket. In contrast, from the "approximation" perspective, since each observed full ranking Ti is simply a linear extension of the given "ground truth" bucket order G, items in a big bucket b in G are forced to have different median ranks, and as a result b will have a big sum of deviations. Thus, minimizing the sum of deviations may result in an undesirable scenario that big buckets are mostly decomposed into small ones. In this paper, we propose a novel heuristic called Abnormal Rank Gap to capture the inter-bucket dissimilarity for better bucket forming. In addition, we propose to use the "closeness" on multiple quantile ranks to determine if two items should be put into the same bucket. We develop a novel bucket order discovering method termed the Bucket Gap algorithm. Our extensive experiments demonstrate that the Bucket Gap algorithm significantly outperforms the major related work, i.e., the Bucket Pivot algorithm. In particular, the error distance of the generated bucket order can be reduced by about 30% on a real paleontological dataset and the noise tolerance can be increased from 30% to 50% in the synthetic dataset.
Interactive Reconfiguration of Urban Layouts
Authors: Daniel G. Aliaga, Bedřich Beneš, Carlos A. Vanegas, Nathan Andrysco
Venue: IEEE Computer Graphics and Applications (2008)

The layout of an urban space is a complex collection of man-made structures arranged in parcels, city blocks, and neighborhoods. An editor for interactively reconfiguring city layouts exploits geographical information system (GIS) data and provides tools to expand, scale, replace, and move parcels and blocks while efficiently exploiting their connectivity and zoning.
Performance Assessment of Enhanced Just-in-Time Protocol in OBS Networks Taking into Account Control Packet Processing and Optical Switch Configuration Times
Authors: Joel José Puga Coelho Rodrigues, Mário Marques Freire
Venue: Proceedings of the 22nd International Conference on Advanced Information Networking and Applications - Workshops (2008)

Enhanced Just-in-Time (E-JIT) is a new one-way resource reservation protocol for optical burst switching (OBS) networks. This paper investigates the effect of control packet (setup message) processing time and optical switch configuration time on the performance of OBS mesh networks for E-JIT protocol. A performance assessment of E-JIT is presented in comparison with Just-in-Time (JIT) protocol for the following mesh optical burst switching networks: degree-three and degree-four chordal rings, Mesh-torus, NSFNET, ARPANET, and the European Optical Network (EON). Among those topologies, for topologies with nodal degree around three D3T(1,19,7) leads to the best performance, while the worst performance is observed for ARPANET. For network topologies with nodal degree around four, D4T(1,19,3,9) leads to the best performance and the worst is presented by EON. It was shown that the network performance is almost independent of the optical switch configuration time for values smaller than 0.1ms. It was shown that the burst loss probability increases with the increase of the control packet processing time and it was observed that E-JIT may lead to a better performance than JIT.
A curriculum framework for implementing information technology in school education to foster information literacy
Authors: Siu Cheung Kong
Venue: Computers Education (2008)

A literature review of the development of the information technology (IT) curriculum in recent decades in Hong Kong reveals that the aim of the curriculum has shifted from Computer Studies to the development of information literacy (IL). Based on a survey of all schools in Hong Kong and in response to the demand for IL in society, a curriculum framework is proposed that fosters the IL of students. The curriculum framework is based on the rationale of significant learning and designed on the principles of providing authenticity and creating reflection. It consists of three parts: a core IT curriculum; use of knowledge about IT and information processing across curricula; and a school culture that fosters IL. Four issues that are critical for the successful implementation of the proposed curriculum framework are discussed: school-based implementation models; the provision of service learning activities; support from parents; and reduction of the digital divide between students.
Assessing readiness of IP networks to support desktop videoconferencing using OPNET
Authors: K. Salah, P. Calyam, M. I. Buhari
Venue: Journal of Network and Computer Applications (2008)

OPNET is a powerful network design and simulation tool that has gained popularity in industry and academia. However, there exists no known simulation approach on how to deploy a popular real-time network service such as videoconferencing. This paper demonstrates how OPNET can be leveraged to assess the readiness of existing IP networks to support desktop videoconference. To date, OPNET does not have built-in features to support videoconferencing or its deployment. The paper offers remarkable details on how to model and configure OPNET for such a purpose. The paper considers two types of video traffic (viz. fixed and empirical video packet sizes). Empirical video packet sizes are collected from well-known Internet traffic traces. The paper presents in-depth analysis and interpretation of simulation results and shows how to draw proper engineering conclusions.