ppxscal/embedding_network huggingface dataset:
Enhancing Data Flow Testing of Classes through Design by Contract
Authors: Yogesh Singh, Anju Saha
Venue: Proceedings of the Seventh IEEE/ACIS International Conference on Computer and Information Science (icis 2008) (2008)

Design by Contract (DbC) is a methodology to construct quality software. DbC associates the contract pecification (pre and postconditions of methods of class and class invariant) with the design of a class. In this paper, we combine data flow testing and Design by Contract to develop a testing technique called “Data flow testing using Contract”. In this technique a class flow graph is generated from the contract specification of the class and then conventional data flow testing is applied to find the test cases. The advantage of using contract specification is that: it is executable and hence a method in a test case is only executed if its precondition and class invariant are satisfied. If they are not satisfied then it leads to an infeasible sequence. Also, if after executing a method its postcondition is not satisfied then it leads to implementation error in the method. We also compare the testing of a DbC class with a conventional class and find that the number of du pairs is reduced in a DbC class because some of the conditions in conventional class become the part of the precondition in a DbC class.
Architectural challenges of ultra large scale systems
Authors: Mehdi Mirakhorli, Amir Azim Sharifloo, Fereidoon Shams
Venue: Proceedings of the 2nd international workshop on Ultra-large-scale software-intensive systems (2008)

Sheer scale of ULS systems will change everything and make it impossible to rely on our current knowledge and techniques of software development. At first, we need to fully understand the nature and derived challenges from characteristics of these systems, then we should introduce new ideas for how to develop them. As architecture is the key artifact in development of ultra large scale systems, this topic is at the top of the agenda in this research area. In this position paper we try to investigate architectural issues unique to a ULS system, discuss and debat the architectural challenges posed by these systems.
Group mirrors to support interaction regulation in collaborative problem solving
Authors: Patrick Jermann, Pierre Dillenbourg
Venue: Computers Education (2008)

Two experimental studies test the effect of group mirrors upon quantitative and qualitative aspects of participation in collaborative problem solving. Mirroring tools consist of a graphical representation of the group's actions which is dynamically updated and displayed to the collaborators. In addition, metacognitive tools display a standard for desirable behavior. Results show that a mirroring tool did not substantively affect the behavior of subjects while a metacognitive tool led to increased participation in dialogue, including more frequent and precise planning.
On the minimal density of triangles in graphs
Authors: Alexander a. Razborov
Venue: Combinatorics, Probability and Computing (2008)

For a fixed ρ ∈ [0, 1], what is (asymptotically) the minimal possible density g3(ρ) of triangles in a graph with edge density ρ? We completely solve this problem by proving that <disp-formula><graphic xlink="S0963548308009085_eqnU1" mime-subtype="gif"><alt-text>$$ g_3(\rho) =\frac{(t-1)\ofb{t-2\sqrt{t(t-\rho(t+1))}}\ofb{t+\sqrt{t(t-\rho(t+1))}}^2}{t^2(t+1)^2},$$</alt-text></graphic></disp-formula> where <inline-graphic mime-subtype="gif" xlink="S0963548308009085_inline1"><alt-text>$t\df \lfloor 1/(1-\rho)\rfloor$</alt-text></inline-graphic> is the integer such that <inline-graphic mime-subtype="gif" xlink="S0963548308009085_inline2"><alt-text>$\rho\in\bigl[ 1-\frac 1t,1-\frac 1{t+1}\bigr]$</alt-text></inline-graphic>.
Signal Separation for Non-invasive Monitoring of Foetal Heartbeat
Authors: R. Acharyya, Neil Scott, Eberhard Deuss, Paul Teal, Jurgen Flierl
Venue: Proceedings of the 2008 International Conference on BioMedical Engineering and Informatics - Volume 02 (2008)

A blind source separation algorithm is successfully applied to extract foetal heartbeat from a set of acoustic data collected from pregnant women. Several different variations of Independent Component Analysis (ICA) algorithms are applied and tested with actual data and it has been observed that ICA based on maximization of cummulants has successfully separated the foetal as well as the mother’s heart beat.
Learning in Friedberg numberings
Authors: Sanjay Jain, Frank Stephan
Venue: Information and Computation (2008)

In this paper we consider learnability in some special numberings, such as Friedberg numberings, which contain all the recursively enumerable languages, but have simpler grammar equivalence problem compared to acceptable numberings. We show that every explanatorily learnable class can be learnt in some Friedberg numbering. However, such a result does not hold for behaviourally correct learning or finite learning. One can also show that some Friedberg numberings are so restrictive that all classes which can be explanatorily learnt in such Friedberg numberings have only finitely many infinite languages. We also study similar questions for several properties of learners such as consistency, conservativeness, prudence, iterativeness and non-U-shaped learning. Besides Friedberg numberings, we also consider the above problems for programming systems with K-recursive grammar equivalence problem.
Network distance estimation with dynamic landmark triangles
Authors: Zhihua Wen, Michael Rabinovich
Venue: ACM SIGMETRICS Performance Evaluation Review (2008)

This paper describes an efficient and accurate approach to estimate the network distance between arbitrary Internet hosts. We use three landmark hosts forming a triangle in two-dimensional space to estimate the distance between arbitrary hosts with simple trigonometrical calculations. To improve the accuracy of estimation, we dynamically choose the "best" triangle for a given pair of hosts using a heuristic algorithm. Our experiments show that this approach achieves both lower computational and network probing cost over the classic landmarks-based approach while producing more accurate estimates.
Adaptive Bandwidth Management and Reservation Scheme in Heterogeneous Wireless Networks
Authors: I-Shyan Hwang, Bor-Jiunn Hwang, Ling-Feng Ku, Pen-Ming Chang
Venue: Proceedings of the 2008 IEEE International Conference on Sensor Networks, Ubiquitous, and Trustworthy Computing (sutc 2008) (2008)

In order to support multiple types of service with different QoS requirements in heterogeneous wireless networks, efficient resource management, call admission control strategies, and mobility management are important issues. In this paper, we propose Bandwidth Management Strategy 1 (BMS1), Bandwidth Management Strategy 2 (BMS2) and reservation scheme with Fuzzy controller for real-time services. Simulation result shows that the proposed methods balance resource utilization outperforms the previous work and traditional CAC by improving the call reject probability (CRP).
A Web-Based Interactive Monitoring System for Molecular Simulation
Authors: Jun Lee, Taedoo Hwang, Jonghyun Lee, Sungjun Park, YoungJin Choi, Karpjoo Jeong, Jee-In Kim
Venue: Proceedings of the 2007 Frontiers in the Convergence of Bioscience and Information Technologies (2007)

Molecular simulation such as molecular dynamics requires high computing capacity of large scale clusters or supercomputers to complete its experiment. Since it is hard to calculate with general computer, high computing power such as grid computing is required through the web. After the simulation, the result file is created and replicated to the web. To analysis the experiment, biologist has to download it, but large amount of file takes many times to download and analysis the result. We propose a web-based interactive monitoring system for molecular simulation. The grid system is used for computing equations of molecular simulations. The results can be viewed through 3D animations and manipulated by interactive manners. The operations can be performed through web browsers over the Internet. The proposed system was evaluated in performance in comparison with previous approaches. The proposed system enable biologist to analysis the simulation results five times faster than previous tools.
Molecular modeling ab initio methods and numerical integration
Authors: Elise de Doncker
Venue: Proceedings of the 10th WSEAS International Conference on APPLIED MATHEMATICS (2006)

Molecular quantum mechanics relates molecular properties to the motion and interactions of the constituting electrons and nuclei. In principle, solving the Schrödinger equation HΨ = EΨ, leading to ab initio approaches (independent of experiment), can predict chemical phenomena. We consider the study of molecules using Hartree's self-consistent field approximation. Computationally, the Hartree-Fock method requires evaluating large sets of integrals, of forms which depend on the type of basis functions used for the expansion of the wave functions. We explore Slater type basis functions and numerical integration for the resulting integrals.
Hybrid Integration of Bandgap Reference Circuits Using Silicon ICs and Germanium Devices
Authors: Jae Wook Kim, Boris Murmann, Robert Dutton
Venue: Proceedings of the 9th international symposium on Quality Electronic Design (2008)

Low-voltage hybrid silicon-germanium bandgap reference circuits that can defy the voltage scaling limits of those realized in purely silicon-based technologies are implemented. Germanium diodes replace silicon diodes in two conventional bandgap reference circuits fabricated in a 0.18-um Si CMOS process, and experimental results validate the benefit of exploiting a low bandgap material. The output references are measured as 670 mV and 310 mV with 9.3 mV (287 ppm/°C) and 4.6 mV (302 ppm/°C) variation, respectively, over 5 ~ 56 °C. In addition, the high temperature characteristics limiting the operation range related to low bandgap are investigated.
Optimal recursive digital filter design using improved genetic algorithm
Authors: Morris Abraham Gnanamuthu Ezra, K. Ramar, C. Eswaran
Venue: Proceedings of the 6th WSEAS International Conference on Signal, Speech and Image Processing (2006)

In the process of designing digital recursive filters to satisfy a given magnitude response. the designer may end up with an unstable filter. This unstable filter can be stabilized using methods such as Planar Least Sqare Inverse technique, Complex Ceptrum Method etc. The Planar Least Square Inverse technique is supposed to preserve the desired magnitude response which is found to be not true in all cases. Hence a new method of designing recursive filters using the improved genetic optimization algorithm is presented in this paper. The optimally designed filter will be stable and will have a magnitude response almost similar to the desired magnitude response.
Resource Allocation for Coexisting ZigBee-Based Personal Area Networks
Authors: Niwat Thepvilojanapong, Shinji Motegi, Akira Idoue, Hiroki Horiuchi
Venue: Proceedings of the Seventh International Conference on Networking (2008)

Personal healthcare is a promising market of a Personal Area Network (PAN). The PAN consists of a data collector and multiple wearable sensors which must send data to the collector according to the frequency specified by each PAN. The data collector may be any hand-held or portable device, e.g., a mobile phone, a PDA, or a wristwatch. An individual user needs a PAN in order to detect, track, or manage his/her health. Multiple PANs for such purposes are likely to coexist in a same area, especially a place where a large number of users exist. Because multiple PANs must share resources (e.g., wireless channels, transmitting time) in this scenario, a problem of packet collisions among such PANs is unavoidable. As a result, the personal healthcare system using PAN cannot be provided as a service for the users because the data collector cannot collect sensing data from each sensor correctly. This paper proposes an adaptive scheme to allocate resources for coexisting PANs. The scheme distinguishes a PAN and a node when allocating resources such as wireless channel and transmitting time. Resources are dynamically allocated according to the current number of PANs that exist in the same area. In particular, the proposed scheme automatically reallocates resources when any PANs come into or leave from the coexisting area. As one of salient features, the scheme allocates transmitting time to meet a requirement on reporting interval determined by an application. Thus applications that are sensitive to delay can collect sensing data correctly and in time. The evaluation results show that our scheme achieves higher packet delivery rate than the standard ZigBee.
HOVER: hybrid on-demand distance vector routing for wireless mesh networks
Authors: Stephan Mir, Asad Amir Pirzada, Marius Portmann
Venue: Proceedings of the thirty-first Australasian conference on Computer science - Volume 74 (2008)

Hybrid Wireless Mesh Networks are a combination of mobile ad hoc networks and infrastructure wireless mesh networks, consisting of two types of nodes: mobile Mesh Clients and static Mesh Routers. Mesh Routers, which are typically equipped with multiple radios, provide a wireless multi-hop backhaul. The resource constrained Mesh Clients also participate in the routing and forwarding of packets to extend the reach of the network. Current ad-hoc routing protocols have been designed for relatively homogeneous networks and do not perform well in Hybrid Wireless Mesh Networks. In this paper, we present HOVER (Hybrid On-demand Distance Vector Routing), a modified version of the AODV routing protocol, that achieves significant performance improvements in terms of packet delivery and latency in Hybrid Wireless Mesh Networks. Our modifications include a link quality estimation technique based on HELLO packets, a new routing metric that differentiates between node types, and a channel selection scheme that minimises interference in multi-radio mesh networks. We present an evaluation of our improvements via extensive simulations. We further show the practicality of the protocol through prototype implementation and provide measurement results obtained from our test-bed.
Proceedings of the 2008 conference on BEyond time and errors: novel evaLuation methods for Information Visualization
Venue: AVI (2008)

Information visualization systems allow users to produce insights, innovations, and discoveries. However, to understand these complex behaviors, evaluation efforts must be targeted at the component level, the system level, and the work environment level. Some components can be evaluated with metrics that can be observed or computed but many others require empirical user evaluations. Usability studies still tend to be designed in an ad hoc manner, focusing on particular systems, addressing only time and errors issues, or failing to produce reusable and robust results. Intrinsic quality metrics are rare despite their necessity for true comparative evaluations. Controlled experiments are the most common evaluation technique but there is a growing sense in the community that information visualization systems need new approaches to evaluation, such as longitudinal field studies, insight based evaluation and metrics adapted to the exploratory nature of discovery. We can conclude that while the overall use of information visualizations is accelerating, the growth of techniques for the evaluation of these systems has been slow. Our community is confronted with questions such as: &bull; "For this set of task, which visualization is best?" &bull; "How can I measure the utility of a visualization?" &bull; "Does the visualization I developed meet the target users' needs?" An initial workshop, BELIV'06, was conducted at the Advanced Visual Interfaces (AVI) conference to address these questions. The workshop was well attended, featuring lively discussions about the limits of current practices and several novel exploratory techniques for evaluation were presented. Attendees have repeatedly expressed to us the wish to repeat the workshop. For BELIV'08 our aim was twofold: we would like (1) to continue the exploration of novel evaluation methods and (2) structure the knowledge on evaluation in information visualization around a schema, where researchers can easily identify unsolved problems and research gaps. The scientific program of BELIV'08 is based on two different contributions: research papers and position papers. Research papers have been presented together with position papers, in order to produce a more animated discussion. Continuing the line of BELIV'06, research papers are published in the ACM Digital Library.
Time-division multiuser MIMO with statistical feedback
Authors: Kai-Kit Wong, Jia Chen
Venue: EURASIP Journal on Advances in Signal Processing (2008)

This paper investigates a time-division multiuser multiple-input multiple-output (MIMO) antenna system in K-block flat fading where users are given individual outage rate probability constraints and only one user accesses the channel at any given time slot (or block). Assuming a downlink channel and that the transmitter knows only the statistical information about the channel, our aim is to minimize the overall transmit power for achieving the users' outage constraint by jointly optimizing the power allocation and the time-sharing (i.e., the number of time slots) of the users. This paper first derives the so-called minimum power equation (MPE) to solve for the minimum transmit power required for attaining a given outage rate probability of a single-user MIMO block-fading channel if the number of blocks is predetermined. We then construct a convex optimization problem, which can mimic the original problem structure and permits to jointly consider the power consumption and the probability constraints of the users, to give a suboptimal multiuser time-sharing solution. This is finally combined with the MPE to provide a joint power allocation and time-sharing solution for the time-division multiuser MIMO system. Numerical results demonstrate that the proposed scheme performs nearly the same as the global optimum with inappreciable difference.
Automatic acquisition of inflectional lexica for morphological normalisation
Authors: J. Šnajder, B. Dalbelo Bašić, M. Tadić
Venue: Information Processing and Management: an International Journal (2008)

Due to natural language morphology, words can take on various morphological forms. Morphological normalisation - often used in information retrieval and text mining systems - conflates morphological variants of a word to a single representative form. In this paper, we describe an approach to lexicon-based inflectional normalisation. This approach is in between stemming and lemmatisation, and is suitable for morphological normalisation of inflectionally complex languages. To eliminate the immense effort required to compile the lexicon by hand, we focus on the problem of acquiring automatically an inflectional morphological lexicon from raw corpora. We propose a convenient and highly expressive morphology representation formalism on which the acquisition procedure is based. Our approach is applied to the morphologically complex Croatian language, but it should be equally applicable to other languages of similar morphological complexity. Experimental results show that our approach can be used to acquire a lexicon whose linguistic quality allows for rather good normalisation performance.
Towards individualized software engineering: empirical studies should collect psychometrics
Authors: Robert Feldt, Richard Torkar, Lefteris Angelis, Maria Samuelsson
Venue: Proceedings of the 2008 international workshop on Cooperative and human aspects of software engineering (2008)

Even though software is developed by humans, research in software engineering primarily focuses on the technologies, methods and processes they use while disregarding the importance of the humans themselves. In this paper we argue that most studies in software engineering should give much more weight to human factors. In particular empirical software engineering studies involving human developers should always consider collecting psychometric data on the humans involved. We focus on personality as one important psychometric factor and present initial results from an empirical study investigating correlations between personality and attitudes to software engineering processes and tools. We discuss what are currently hindering a more wide-spread use of psychometrics and how overcoming these hurdles could lead to a more individualized software engineering.
Two-dimensional Imaging and Tracking of Single Quantum dot-FRET
Authors: Jiamin Li, Danying Lin, Wanyun Ma
Venue: Proceedings of the 2008 International Conference on BioMedical Engineering and Informatics - Volume 02 (2008)

Using a custom-made setup ICCD-DualView-TIRFM system, we have successfully performed two-dimensional imaging and tracking of fluorescence resonance energy transfer (FRET)–occurring single quantum dot and its energy acceptor Cy5. This work laid a foundation for the further application of quantum dot-FRET in life sciences.
Spectral analysis of microarray gene expression time series data of Plasmodium falciparum
Authors: Liping Du, Shuanhu Wu, Alan Wee-Chung Liew, David K. Smith, Hong Yan
Venue: International Journal of Bioinformatics Research and Applications (2008)

We propose a new strategy to analyse the periodicity of gene expression profiles using Singular Spectrum Analysis (SSA) and Autoregressive (AR) model based spectral estimation. By combining the advantages of SSA and AR modelling, more periodic genes are extracted in the Plasmodium falciparum data set, compared with the classical Fourier analysis technique. We are able to identify more gene targets for new drug discovery, and by checking against the seven well-known malaria vaccine candidates, we have found five additional genes that warrant further biological verification.
On the use of organisation modelling techniques to address biological organisation
Authors: Tibor Bosse, Catholijn M. Jonker, Jan Treur
Venue: Multiagent and Grid Systems (2007)

This paper explores how the dynamics of complex biological processes can be modelled and simulated as an organisation of multiple agents. This modelling perspective identifies organisational structure occurring in complex decentralised processes and handles complexity of the analysis of the dynamics by structuring these dynamics according to an organisational structure. More specifically, dynamic properties at different levels of aggregation in the organisational structure are identified, and related to each other according to the organisational structure. The applicability of this organisational modelling approach to address complexity in biological context is illustrated by two case studies: the organisation of intracellular processes and the organisation of the circulatory system.
A scalability study of web-native information visualization
Authors: Donald W. Johnson, T. J. Jankun-Kelly
Venue: Proceedings of graphics interface 2008 (2008)

Several web-native information visualization methods (SVG, HTML5's Canvas, native HTML) are studied to contrast their performances at different data scales. Using Java implementations of parallel coordinates and squarified treemaps for comparison, we explore the design space of these web-based technologies in order to determine what design trade-offs are required.