ppxscal/embedding_network huggingface dataset:
Multiple block structure-preserving reduced order modeling of interconnect circuits
Authors: Ning Mi, Sheldon X. -D. Tan, Boyuan Yan
Venue: Integration, the VLSI Journal (2009)

In this paper, we propose a generalized multiple-block structure-preserving reduced order interconnect macromodeling method (BSPRIM). Our approach extends the structure-preserving model order reduction (MOR) method SPRIM [R.W. Freund, SPRIM: structure-preserving reduced-order interconnect macromodeling, in: Proceedings of International Conference on Computer Aided Design (ICCAD), 2004, pp. 80-87] into more general block forms. We first show how an SPRIM-like structure-preserving MOR method can be extended to deal with admittance RLC circuit matrices and show that the 2q moments are still matched and symmetry is preserved. Then we present the new BSPRIM method to deal with more circuit partitions for linear dynamic circuits formulated in impedance and admittance forms. The reduced models by BSPRIM will still match the 2q moments and preserve the circuit structure properties like symmetry as SPRIM does. We also show that BSPRIM can build the compact models with similar size and accuracy of that produced by traditional projection based methods but using less computation costs. Experimental results show that BSPRIM outperforms SPRIM in terms of accuracy with more partitions and outperforms PRIMA with less CPU times for generating the same accurate models.
ProfDistS
Authors: Matthias Wolf, Benjamin Ruderisch, Thomas Dandekar, Jörg Schultz, Tobias Müller
Venue: Bioinformatics (2008)

Motivation: The Profile Neighbor Joining (PNJ) algorithm as implemented in the software ProfDist is computationally efficient in reconstructing very large trees. Besides the huge amount of sequence data the structure is important in RNA alignment analysis and phylogenetic reconstruction. Results: For this ProfDistS provides a phylogenetic workflow that uses individual RNA secondary structures in reconstructing phylogenies based on sequence-structure alignments—using PNJ with manual or iterative and automatic profile definition. Moreover, ProfDistS can deal also with protein sequences. Availability: ProfDistS is freely available for non-commercial use for Windows, Linux and MAC operating systems at http://profdist.bioapps.biozentrum.uni-wuerzburg.de. Contact:tobias.mueller@biozentrum.uni-wuerzburg.de; matthias.wolf@biozentrum.uni-wuerzburg.de
What makes a good bug report?
Authors: Nicolas Bettenburg, Sascha Just, Adrian Schröter, Cathrin Weiss, Rahul Premraj, Thomas Zimmermann
Venue: Proceedings of the 16th ACM SIGSOFT International Symposium on Foundations of software engineering (2008)

In software development, bug reports provide crucial information to developers. However, these reports widely differ in their quality. We conducted a survey among developers and users of APACHE, ECLIPSE, and MOZILLA to find out what makes a good bug report. The analysis of the 466 responses revealed an information mismatch between what developers need and what users supply. Most developers consider steps to reproduce, stack traces, and test cases as helpful, which are at the same time most difficult to provide for users. Such insight is helpful to design new bug tracking tools that guide users at collecting and providing more helpful information. Our CUEZILLA prototype is such a tool and measures the quality of new bug reports; it also recommends which elements should be added to improve the quality. We trained CUEZILLA on a sample of 289 bug reports, rated by developers as part of the survey. In our experiments, CUEZILLA was able to predict the quality of 31--48% of bug reports accurately.
Propagating functional dependencies with conditions
Authors: Wenfei Fan, Shuai Ma, Yanli Hu, Jie Liu, Yinghui Wu
Venue: Proceedings of the VLDB Endowment (2008)

The dependency propagation problem is to determine, given a view defined on data sources and a set of dependencies on the sources, whether another dependency is guaranteed to hold on the view. This paper investigates dependency propagation for recently proposed conditional functional dependencies (CFDs). The need for this study is evident in data integration, exchange and cleaning since dependencies on data sources often only hold conditionally on the view. We investigate dependency propagation for views defined in various fragments of relational algebra, CFDs as view dependencies, and for source dependencies given as either CFDs or traditional functional dependencies (FDs). (a) We establish lower and upper bounds, all matching, ranging from PTIME to undecidable. These not only provide the first results for CFD propagation, but also extend the classical work of FD propagation by giving new complexity bounds in the presence of finite domains. (b) We provide the first algorithm for computing a minimal cover of all CFDs propagated via SPC views; the algorithm has the same complexity as one of the most efficient algorithms for computing a cover of FDs propagated via a projection view, despite the increased expressive power of CFDs and SPC views. (c) We experimentally verify that the algorithm is efficient.
Choosing attribute weights for item dissimilarity using clikstream data with an application to a product catalog map
Authors: Martijn Kagie, Michiel van Wezel, Patrick J.F. Groenen
Venue: Proceedings of the 2008 ACM conference on Recommender systems (2008)

In content- and knowledge-based recommender systems often a measure of (dis)similarity between items is used. Frequently, this measure is based on the attributes of the items. However, which attributes are important for the users of the system remains an important question to answer. In this paper, we present an approach to determine attribute weights in a dissimilarity measure using clickstream data of an e-commerce website. Counted is how many times products are sold and based on this a Poisson regression model is estimated. Estimates of this model are then used to determine the attribute weights in the dissimilarity measure. We show an application of this approach on a product catalog of MP3 players provided by Compare Group, owner of the Dutch price comparison site http://www.vergelijk.nl, and show how the dissimilarity measure can be used to improve 2D product catalog visualizations.
Accuracy estimate and optimization techniques for SimRank computation
Authors: Dmitry Lizorkin, Pavel Velikhov, Maxim Grinev, Denis Turdakov
Venue: Proceedings of the VLDB Endowment (2008)

The measure of similarity between objects is a very useful tool in many areas of computer science, including information retrieval. SimRank is a simple and intuitive measure of this kind, based on graph-theoretic model. SimRank is typically computed iteratively, in the spirit of PageRank. However, existing work on SimRank lacks accuracy estimation of iterative computation and has discouraging time complexity. In this paper we present a technique to estimate the accuracy of computing SimRank iteratively. This technique provides a way to find out the number of iterations required to achieve a desired accuracy when computing SimRank. We also present optimization techniques that improve the computational complexity of the iterative algorithm from O(n4) to O(n3) in the worst case. We also introduce a threshold sieving heuristic and its accuracy estimation that further improves the efficiency of the method. As a practical illustration of our techniques we computed SimRank scores on a subset of English Wikipedia corpus, consisting of the complete set of articles and category links.
Effects of atmospheric water and surface wind on passive microwave retrievals of sea ice concentration: a simulation study
Authors: Dong-Bin Shin, Long S. Chiu, Pablo Clemente-Colon
Venue: International Journal of Remote Sensing (2008)

The atmospheric effects on the retrieval of sea ice concentration from passive microwave sensors were examined using simulated data typical for the Arctic summer. The simulation includes atmospheric contributions of cloud liquid water (CLW), water vapour (WV) and surface wind on the microwave signatures. A plane parallel radiative transfer model was used to compute brightness temperatures at SSM/I frequencies over surfaces that contained open water, first-year (FY) ice, multi-year (MY) ice and their combinations. Synthetic retrievals were performed using the NASA Team (NT) algorithm for the estimation of sea ice concentrations. Our results show that if the satellite sensor's field of view is filled with only FY ice, the retrieval is hardly affected by the atmospheric conditions because of the high contrast between emission signals from the FY ice surface and the atmosphere. Pure MY ice concentration is generally underestimated because of the low MY ice surface emissivity, which results in the enhancement of emission signals from the atmosphere. In marginal ice areas, the atmospheric and surface effects tend to degrade the accuracy at low sea ice concentrations. FY ice concentration is overestimated and MY ice concentration is underestimated in the presence of atmospheric water and surface wind at low ice concentration. Moreover, strong surface wind appears to be more important than atmospheric water in contributing to the retrieval errors of total ice concentrations over marginal ice zones.
Learning to extract form labels
Authors: Hoa Nguyen, Thanh Nguyen, Juliana Freire
Venue: Proceedings of the VLDB Endowment (2008)

In this paper we describe a new approach to extract element labels from Web form interfaces. Having these labels is a requirement for several techniques that attempt to retrieve and integrate information that is hidden behind form interfaces, such as hidden Web crawlers and metasearchers. However, given the wide variation in form layout, even within a well-defined domain, automatically extracting these labels is a challenging problem. Whereas previous approaches to this problem have relied on heuristics and manually specified extraction rules, our technique makes use of a learning classifier ensemble to identify element-label mappings; and it applies a reconciliation step which leverages the classifier-derived mappings to boost extraction accuracy. We present a detailed experimental evaluation using over three thousand Web forms. Our results show that our approach is effective: it obtains significantly higher accuracy and is more robust to variability in form layout than previous label extraction techniques.
Software Innovation for E-Government Expansion
Authors: Stefania Pierno, Luigi Romano, Luisa Capuano, Massimo Magaldi, Luca Bevilacqua
Venue: Proceedings of the OTM 2008 Confederated International Conferences, CoopIS, DOA, GADA, IS, and ODBASE 2008. Part I on On the Move to Meaningful Internet Systems: (2008)

SIEGE (Software Innovation for E-Government Expansion) is an ongoing research project, co-funded by the Italian Ministry for Scientific Research.SIEGE is being carried out by Engineering, the leading Italian IT company, in partnership with DIIMA, the department for informatics and applied mathematics of Salerno University.As its name suggests, SIEGE deals with software innovation in the field of e-Government.It is being focused on research topics widely recognized by the e-Government research community as relevant to bring efficiency and innovation in public service delivery: interoperability, workflow management system, GRID and semantics.In this paper we describe our effort to accommodate them into a coherent architectural model. Believing that the sharing of "resources" will be paramount in supporting delivery of innovative, and cost efficient e-Government services, we chose an OGSA based architecture.
On the error-correcting capability of LDPC codes
Authors: K. Sh. Zigangirov, A. E. Pusane, D. K. Zigangirov, D. J. Costello,  Jr.
Venue: Problems of Information Transmission (2008)

We consider the ensemble of low-density parity-check (LDPC) codes introduced by Gallager [1]. The Zyablov-Pinsker majority-logic iterative algorithm [2] for decoding LDPC codes is analyzed on the binary symmetric channel. An analytical lower bound on the error-correcting capability ¿ max that grows linearly in the code block length is obtained.
Context-based design of robotic systems
Authors: Daniele Calisi, Luca Iocchi, Daniele Nardi, Carlo Matteo Scalzo, Vittorio Amos Ziparo
Venue: Robotics and Autonomous Systems (2008)

The need for improving the robustness, as well as the ability to adapt to different operational conditions, is a key requirement for a wider deployment of robots in many application domains. In this paper, we present an approach to the design of robotic systems, that is based on the explicit representation of knowledge about context. The goal of the approach is to improve the system's performance, by dynamically tailoring the functionalities of the robot to the specific features of the situation at hand. While the idea of using contextual knowledge is not new, the proposed approach generalizes previous work, and its advantages are discussed through a case study including several experiments. In particular, we identify many attempts to use contextual knowledge in several basic functionalities of a mobile robot such as: behavior, navigation, exploration, localization, mapping and perception. We then show how re-designing our mobile platform with a common representation of contextual knowledge, leads to interesting improvements in many of the above mentioned components, thus achieving greater flexibility and robustness in the face of different situations. Moreover, a clear separation of contextual knowledge leads to a design methodology, which supports the design of small specialized system components instead of complex self-contained subsystems.
An adaptive resource partitioning algorithm for SMT processors
Authors: Huaping Wang, Israel Koren, C. Mani Krishna
Venue: Proceedings of the 17th international conference on Parallel architectures and compilation techniques (2008)

Simultaneous Multithreading (SMT) increases processor throughput by allowing the parallel execution of several threads. However, fully sharing processor resources may cause resource monopolization by a single thread or other misallocations, resulting in overall performance degradation. Static resource partitioning techniques have been suggested, but are not as effective as dynamically controlling the resource usage of each thread since program behavior does change during its execution. In this paper, we propose an Adaptive Resource Partitioning Algorithm (ARPA) that dynamically assigns resources to threads according to thread behavior changes. ARPA analyzes the resource usage efficiency of each thread in a time period and assigns more resources to threads which can use them in a more efficient way. The purpose of ARPA is to improve the efficiency of resource utilization, thereby improving overall instruction throughput. Our simulation results on a set of 42 multiprogramming workloads show that ARPA outperforms the traditional fetch policy ICOUNT by 55.8% with regard to overall instruction throughput and achieves a 33.8% improvement over Static Partitioning. It also outperforms the current best dynamic resource allocation technique, Hill-climbing, by 5.7%. Considering fairness accorded to each thread, ARPA attains 43.6%, 18.5% and 9.2% improvements over ICOUNT, Static Partitioning and Hill-climbing, respectively, using a common fairness metric.
A self-adaptive placement protocol for mobile directories in MANETs
Authors: Sergio Gonzalez-Valenzuela, Son T. Vuong, Victor C.M. Leung
Venue: Proceedings of the 11th international symposium on Modeling, analysis and simulation of wireless and mobile systems (2008)

We present our Service Directory Placement Protocol (SDPP), a multi-directory scheme for service discovery in Mobile Ad-hoc Networks (MANETs). SDPP promotes the use of both fixed and mobile directories co-existing in a hybrid setting comprised of devices with different memory availability. Our proposed system is based on a heuristic approach, whose performance is optimized by formulating the directory-placement problem as a Semi-Markov Decision Process solved by Q-Learning. Performance evaluations reveal typical performance gains ranging between 15% and 75% of SDPP compared with a default broadcast approach for MANETs comprised of hosts moving at pedestrian speeds. A two-step process for practical implementation based on "off-line" computer simulations is also described.
A mapping and localization framework for scalable appearance-based navigation
Authors: Siniša Šegvić, Anthony Remazeilles, Albert Diosi, François Chaumette
Venue: Computer Vision and Image Understanding (2009)

This paper presents a vision framework which enables feature-oriented appearance-based navigation in large outdoor environments containing other moving objects. The framework is based on a hybrid topological-geometrical environment representation, constructed from a learning sequence acquired during a robot motion under human control. At the higher topological layer, the representation contains a graph of key-images such that incident nodes share many natural landmarks. The lower geometrical layer enables to predict the projections of the mapped landmarks onto the current image, in order to be able to start (or resume) their tracking on the fly. The desired navigation functionality is achieved without requiring global geometrical consistency of the underlying environment representation. The framework has been experimentally validated in demanding and cluttered outdoor environments, under different imaging conditions. The experiments have been performed on many long sequences acquired from moving cars, as well as in large-scale real-time navigation experiments relying exclusively on a single perspective vision sensor. The obtained results confirm the viability of the proposed hybrid approach and indicate interesting directions for future work.
Topography-based modeling to estimate percent vegetation cover in semi-arid Mu Us sandy land, China
Authors: Cunyong Ju, Tijiu Cai, Xiaohui Yang
Venue: Computers and Electronics in Agriculture (2008)

Desertification is an important ecological and environmental problem that concerns the whole globe. Percent vegetation cover is closely related to occurrence and degree of desertification, and its estimation is essential to monitoring and assessing land desertification. Normalized Different Vegetation Index (NDVI), an indicator widely employed to estimate percent vegetation cover, did not work well because of heterogeneous topographical features and vegetation cover in Mu Us sandy land. We selected variables according to correlations between them and vegetation cover fraction and estimated percent vegetation cover with the general regression neural network (GRNN) model and partial least squares (PLSs) regression linear model. Results indicated that correlations between remote sensing indices and vegetation cover fraction varied with topographical feature types. We also found that if field samples were classified with topographical features before estimation, prediction precision of the model was improved for individual plots. This research provides new alternatives for more precise vegetation cover estimation in the semi-arid area of China.
An environmental perspective on large-scale genome clustering based on metabolic capabilities
Authors: Gabi Kastenmüller, Johann Gasteiger, Hans-Werner Mewes
Venue: Bioinformatics (2008)

Motivation: In principle, an organism's ability to survive in a speci.c environment, is an observable result of the organism's regulatory and metabolic capabilities. Nonetheless, current knowledge about the global relation of the metabolisms and the niches of organisms is still limited. Results: In order to further investigate this relation, we grouped species showing similar metabolic capabilities and systematically mapped their habitats onto these groups. For this purpose, we predicted the metabolic capabilities for 214 sequenced genomes. Based on these predictions, we grouped the genomes by hierarchical clustering. Finally, we mapped different environmental conditions and diseases related to the genomes onto the resulting clusters. This mapping uncovered several conditions and diseases that were unexpectedly enriched in clusters of metabolically similar species. As an example, Encephalitozoon cuniculi—a microsporidian causing a multisystemic disease accompanied by CNS problems in rabbits— occurred in the same metabolism-based cluster as bacteria causing similar symptoms in humans. Supplementary information: Supplementary data are available at Bioinformatics online. Contact: g.kastenmueller@helmholtz-muenchen.de
Centralized feedback-driven rate allocation mechanism for CSMA/CA-based wireless mesh networks
Authors: Kamran Jamshaid, Paul A.S. Ward
Venue: Proceedings of the 11th international symposium on Modeling, analysis and simulation of wireless and mobile systems (2008)

Wireless Mesh Networks (WMNs) based on commodity 802.11 radios exhibit extreme unfairness, including starvation, in the presence of backlogged traffic sources. While the underlying reasons for this performance degradation are well understood, yet only a few of the proposed solutions are compatible with the current generation of closed 802.11 firmware/hardware. Most existing proposals limit sources to their fair share through a distributed rate control mechanism, in the process incurring a significant overhead to enable such local computation of fair rates. In prior work we validated the feasibility of centralized rate control in WMNs, assuming knowledge of network topology and link interference. In this work we remove this requirement and propose a zero-overhead centralized rate controller. This controller can be implemented at traffic aggregation points such as gateway routers. Its response is driven by a feedback-based mechanism, allowing it to adapt to changes in network and traffic conditions. Simulations show that our controller can improve the fairness metrics by a factor of 3 over networks without any rate control, and is within 2% of the fairness metrics achieved by a centralized controller with omniscient knowledge of network topology and link interference.
On Medical Image Filtering Based on Rough Set Theory
Authors: Yi Xie
Venue: Proceedings of the 2008 Fifth International Conference on Fuzzy Systems and Knowledge Discovery - Volume 05 (2008)

Medical images contain much pathology information. In order to denoise the images with speckle noise and fuzzy edge, a new medical image filtering method based on rough set theory is proposed on the basis of analyzing the traditional filtering methods. Through dividing the appropriate subset, the rough sets filter is realized by applying different denoise method to different subsets. Experimental results show that the proposed method can reduce the noise and improve the peak signal/ noise ratio (PSNR). It also has the advantage of calculating easy and flexibility.
A comparative study on thyroid disease diagnosis using neural networks
Authors: Feyzullah Temurtas
Venue: Expert Systems with Applications: An International Journal (2009)

Thyroid hormones produced by the thyroid gland help regulation of the body's metabolism. Abnormalities of thyroid function are usually related to production of too little thyroid hormone (hypothyroidism) or production of too much thyroid hormone (hyperthyroidism). Thyroid disease diagnosis via proper interpretation of the thyroid data is an important classification problem. In this study, a comparative thyroid disease diagnosis were realized by using multilayer, probabilistic, and learning vector quantization neural networks. For this purpose, thyroid disease dataset which is taken from UCI machine learning database was used.