ppxscal/embedding_network huggingface dataset:
Virtual chat in an enquiry-based team project
Authors: Adrian Albin-Clark
Venue: Proceedings of the 13th annual conference on Innovation and technology in computer science education (2008)

In an enquiry-based first year team project, students are encouraged to develop their social skills through both non-technical and technical activities which, over the course of the year, increase in complexity, and have higher demands in terms of interaction. During a short period of tutor absence, two virtual chat sessions were conducted to maintain continuity in the tutorial programme. The interactions were analysed by examining a chat log, which showed a work ethic similar to that usually encountered in a traditional tutorial. Potential uses of chat software are then considered for other areas of this course unit.
Context Awareness Systems Design and Reasoning
Authors: Jin Song Dong, Yuzhang Feng, Jing Sun, Jun Sun
Venue: Proceedings of the Second International Symposium on Leveraging Applications of Formal Methods, Verification and Validation (2006)

This paper reports a recent research investigation on an integrated formal approach to model and verify sensor constraints in the context awareness systems.
Runtime adaptation in a service-oriented component model
Authors: Florian Irmert, Thomas Fischer, Klaus Meyer-Wegener
Venue: Proceedings of the 2008 international workshop on Software engineering for adaptive and self-managing systems (2008)

Developing software applications which manage, optimize or adapt themselves at runtime requires an architecture which provides adaptation of software components at runtime. An architecture model that has gained a lot of attention in recent years is SOA (service-oriented architecture). In a SOA environment services as well as applications build up complex dependencies. Therefore it is crucial for self-managing SOA applications to adapt services at runtime without interference of the application execution and the service availability. In this paper, we discuss the problems arising from the requirement of runtime adaptation and present our solution by replacing service implementations at execution time in a service-oriented component model. For a seamless integration we strive for a transparent and atomic replacement of a service implementation in respect to the other services/applications.
Efficient search in file-sharing networks
Authors: Paul Burstein, Alan Jay Smith
Venue: Proceedings of the 13th International Conference on Parallel and Distributed Systems - Volume 01 (2007)

Currently, the most popular file-sharing applications have used either centralized or flood-based search algorithms. Napster has been successful in providing a centralized index with presumably perfect query recall. Succeeding, more distributed protocols like Gnutella and Kazaa have used flood-based search procedures in which a query is propagated through an unstructured network. Query result quality in such networks suffers as queries for items that are rare have high probabilities of not being found as the entire corpus is not covered during a search. In this paper, we present a new and improved implementation of a distributed file-sharing system yielding (1) query result quality better than flooding and close to a centralized index, and (2) low-maintenance network overhead. These improvements result from our optimized approaches to (a) high churn rates (clients and servers frequently entering and leaving the system) and (b) skewed workloads (high variation in access frequencies vs. key). High churn rates are addressed by keeping all data in soft state, which is periodically refreshed, such that the loss of a server or client is quickly reflected in the indexes; higher refresh rates imply fewer false positives. Skewed workloads are load balanced with the use of a layer of indirection for placing and locating data, such that data is partitioned and distributed based on the frequency of use. A trace-driven prototype evaluation based on Gnutella system traces shows that our prototype implementation achieves a low network bandwidth, attains max-average load ratios within a factor of three across all servers, and has positive recall values for over 90% of all queries, despite a high churn rate; the recall would be 100% absent churn.
Limiting behavior of the Alizadeh-Haeberly-Overton weighted paths in semidefinite programming
Authors: Zhaosong Lu, Renato D. C. Monteiro
Venue: Optimization Methods Software (2007)

This paper studies the limiting behavior of weighted infeasible central paths for semidefinite programming obtained from centrality equations of the form X S+SX=2 ν W, where W is a fixed positive definite matrix and ν>0 is a parameter, under the assumption that the problem has a strictly complementary primal-dual optimal solution. We present a different and simpler proof than the one given by Preiß and Stoer [Preiß, M. and Stoer, J., 2004, Analysis of infeasible-interior-point paths arising with semidefinite linear complementarity problems. Mathematical Programming 99, 499-520.] that a weighted central path as a function of ν can be extended analytically beyond 0. In addition, the characterization of the limit points of the path and its normalized first-order derivatives is also provided. We also derive an error bound on the distance between a point lying in a certain neighborhood of the central path and the set of primal-dual optimal solutions. Finally, we make some observation for the superlinear convergence of some primal-dual interior point SDP algorithms using AHO neighborhood.
A linearly convergent method for broadcast data allocation
Authors: Kuen-Fang Jea, Jen-Ya Wang, Shih-Ying Chen
Venue: Computers Mathematics with Applications (2008)

In this paper, we deal with an NP-hard minimization problem, performing data allocation over multiple broadcast channels in the wireless environment. Our idea is to solve the discrete case of such a problem by the concept of gradient in the Euclidean space R^n. The theoretical basis of the novel idea ensures the near-optimality of our solution. Furthermore, the experimental results show that the problem can be solved quickly.
Nonparametric Bayesian filtering for location estimation, position tracking, and global localization of mobile terminals in outdoor wireless environments
Authors: Mohamed Khalaf-Allah
Venue: EURASIP Journal on Advances in Signal Processing (2008)

The mobile terminal positioning problem is categorized into three different types according to the availability of (1) initial accurate location information and (2) motion measurement data. Location estimation refers to the mobile positioning problem when both the initial location and motion measurement data are not available. If both are available, the positioning problem is referred to as position tracking. When only motion measurements are available, the problem is known as global localization. These positioning problems were solved within the Bayesian filtering framework. Filter derivation and implementation algorithms are provided with emphasis on the mapping approach. The radio maps of the experimental area have been created by a 3D deterministic radio propagation tool with a grid resolution of 5 m. Real-world experimentation was conducted in a GSM network deployed in a semiurban environment in order to investigate the performance of the different positioning algorithms.
Towards Interactive Visualization for Exploring Conserved Motifs in Noncoding DNA Sequence
Authors: Clare Bates Congdon, H. Rex Gaskins, Gerardo M. Nava, Carolyn Mattingly
Venue: Proceedings of the 2007 Frontiers in the Convergence of Bioscience and Information Technologies (2007)

Computational inference of putative functional elements in noncoding DNA sequence can significantly hasten the search for verified functional elements, such as transcription factor binding sites. However, while computational methods are able to identify promising putative elements, the number of regions of interest may remain unrealistic for experimental validation. Visualization of putative functional elements can assist tremendously in identifying the regions of greatest interest; interactive vizualization allows researchers additional means of asking and answering questions about putative elements. For example, interactive visualizations allow one to look at motifs in the context of verified functional elements or other putative elements, interactively altering the amount of information displayed and the level of resolution at which it is displayed. The work presented here describes initial efforts toward interactive visualization of putative functional elements specifically for our work with conserved elements.
A study of concurrent real-time garbage collectors
Authors: Filip Pizlo, Erez Petrank, Bjarne Steensgaard
Venue: ACM SIGPLAN Notices (2008)

Concurrent garbage collection is highly attractive for real-time systems, because offloading the collection effort from the executing threads allows faster response, allowing for extremely short deadlines at the microseconds level. Concurrent collectors also offer much better scalability over incremental collectors. The main problem with concurrent real-time collectors is their complexity. The first concurrent real-time garbage collector that can support fine synchronization, STOPLESS, has recently been presented by Pizlo et al. In this paper, we propose two additional (and different) algorithms for concurrent real-time garbage collection: CLOVER and CHICKEN. Both collectors obtain reduced complexity over the first collector STOPLESS, but need to trade a benefit for it. We study the algorithmic strengths and weaknesses of CLOVER and CHICKEN and compare them to STOPLESS. Finally, we have implemented all three collectors on the Bartok compiler and runtime for C# and we present measurements to compare their efficiency and responsiveness.
Regularity estimates for convex multifunctions
Authors: A. D. Ioffe, Y. Sekiguchi
Venue: Mathematical Programming: Series A and B (2008)

The main result of the paper contains an exact formula for the rate of regularity of a set-valued mapping with a convex graph. As a consequence we find an exact expression for the rate of regularity of set-valued mappings associated with so-called constraint systems. It turns out that the rate is equal to the upper bound of Robinson-type estimates over all norms in the graph space of the homogenized mapping majorizing the norm of the underlying space. We further introduce a concept of a perfectly regular mapping and find some criteria for perfect regularity.
Exploiting temporal relations in mining hepatitis data
Authors: Tu-Bao Ho, Canh-Hao Nguyen, Saori Kawasaki, Si-Quang Le, Katsuhiko Takabayashi
Venue: New Generation Computing (2007)

Various data mining methods have been developed last few years for hepatitis study using a large temporal and relational database given to the research community. In this work we introduce a novel temporal abstraction method to this study by detecting and exploiting temporal patterns and relations between events in viral hepatitis such as "event A slightly happened before event B and B simultaneously ended with event C". We developed algorithms to first detect significant temporal patterns in temporal sequences and then to identify temporal relations between these temporal patterns. Many findings by data mining methods applied to transactions/graphs of temporal relations shown to be significant by physician evaluation and matching with published in Medline.
Activity-based pen computing
Authors: James A. Landay
Venue: Proceedings of the 4th Eurographics workshop on Sketch-based interfaces and modeling (2007)

Much of pen-computing research to date has focused on how to properly recognize the end user's strokes. Instead, we advocate an activity-driven approach to designing high-value pen-based applications. This will not only result in pen-based applications better suited to target activities but also potentially broaden the research scope of pen-based computing. In this talk I will first discuss why we need a new design methodology, activity-based design, for pen-based computing and then show how it might be applied to pen-based applications and new handheld computing platforms. I will also highlight some of the underlying sensing and inference technologies that can be leveraged to create richer activity-based applications. 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
Custom-specific UV nanoimprint templates and life-time of antisticking layers
Authors: H. Schmitt, M. Zeidler, M. Rommel, A. J. Bauer, H. Ryssel
Venue: Microelectronic Engineering (2008)

UV nanoimprint lithography (UV NIL) is attracting more and more interest, because of its potential to become a high-resolution, low-cost patterning technique. To establish UV NIL as a low-cost patterning technique, the costs of single templates, today obtained from 6025 quartz mask blanks, have to be reduced and the life-time of the antisticking layers has to be optimized. Within this work, a process flow was developed to obtain 49 UV nanoimprint templates with a dimension of 12.5x12.5mm^2 out of a fused silica substrate with a diameter of 150mm. After sawing, etching, and cleaning, the template surfaces were covered with an antisticking layer. Next, the templates were glued onto a template holder to enable their handling with the nanoimprint tool NPS300 from Suss MicroTec. With this process flow, the prize of one single template was strongly reduced compared to quartz templates obtained from 6025 quartz mask blanks. In addition, the life-time of antisticking layers was investigated. For this purpose, the change of the surface tension of antisticking layers after an increasing number of imprints into different UV curing materials was measured and the best combination of antisticking layer and UV curing material was figured out. Finally, silicon substrates were patterned with the optimized template.
Gröbner-free normal forms for boolean polynomials
Authors: Michael Brickenstein, Alexander Dreyer
Venue: Proceedings of the twenty-first international symposium on Symbolic and algebraic computation (2008)

This paper introduces a new method for interpolation of Boolean functions using Boolean polynomials. It was motivated by some problems arising from computational biology, for reverse engineering the structure of mechanisms in gene regulatory networks. For this purpose polynomial expressions have to be generated, which match known state combinations observed during experiments. Earlier approaches using Gröbner techniques have not been powerful enough to treat real-world applications. The proposed method avoids expensive Gröbner basis computations completely by directly calculating reduced normal forms. The problem statement can be described by Boolean polynomials, i.e. polynomials with coefficients in {0,1} and a degree bound of one. Therefore, the reference implementations mentioned in this work are built on the top of the PolyBoRi framework, which has been designed exclusively for the treatment of this special class of polynomials. A series of randomly generated examples is used to demonstrate the performance of the direct method. It is also compared with other approaches, which incorporate Gröbner basis computations.
Privacy Issues in Mobile Advertising
Authors: Evelyne Beatrix Cleff
Venue: International Review of Law, Computers and Technology (2007)

The emergence of the wired Internet and mobile telecommunication networks is creating new opportunities for advertisers to generate new revenue streams through mobile users. As consumer adoption of mobile technology continues to increase, it is only a question of time when mobile advertising becomes an important part of marketing strategies. The development of mobile advertising, however, will be dependent on acceptance and usability issues in order to ensure permission-based advertising. Growing concerns about the protection of the users' privacy have been raised since mobile advertising may become extremely intrusive practices in an intimate personal space. This article focuses on the evaluation of legal problems raised by this novel form of advertising. It is assumed that a technological design, which is in line with the legal framework, will ensure that the benefits of mobile advertising and the consumer willingness to accept mobile advertising will increase.
System architecture for closed-loop PLM
Authors: H. -B. Jun, J. -H. Shin, D. Kiritsis, P. Xirouchakis
Venue: International Journal of Computer Integrated Manufacturing (2007)

The closed-loop product life cycle management (closed-loop PLM) system focuses on tracking and managing the information of whole product life cycle, with possible feedback of information to product life cycle phases. It provides opportunities to reduce the inefficiency of life cycle operations and gain competitiveness. Thanks to the advent of hardware and software related to product identification technologies, e.g. radio frequency identification (RFID) technology, recently the closed-loop PLM has been highlighted as a tool of companies to enhance the performance of their business models. However, implementing the PLM system requires a high level of coordination and integration. To this end, it is prerequisite to investigate what are the main components for closed-loop PLM and how they are related to each other. To address this need, the curent study focuses on the system architecture of closed-loop PLM with respect to business model, hardware, and software.
Observations on Liner Prediction Based Blind Source Extraction Algorithms
Authors: Min Gan, Hongfa Wang, Guoying Yue, Nan Xie, Haibo Zhang
Venue: Proceedings of the Seventh IEEE/ACIS International Conference on Computer and Information Science (icis 2008) (2008)

As we see, blind source extraction (BSE) is advantageous over blind source separation (BSS) when obtaining some underlying source signals from high dimensional signals. Among a variety of BSE algorithms, a large number of algorithms are based on linear prediction (LP-BSE). In this paper we reveal that they are, in nature, minor component analysis (MCA) algorithms, and thus they have some problems that are inherent in MCA algorithms. We also find a switch phenomenon of online LP-BSE algorithms, showing that different parts of a singly extracted signal are the counterparts of different source signals. The two issues should be noticed when one applies these algorithms to practical applications. Computer simulations are given to confirm these observations.
Comparing capacity building frameworks for computer science education in underdeveloped countries: an Asian and African perspective
Authors: Jandelyn D. Plane, Isabella Venter
Venue: Proceedings of the 13th annual conference on Innovation and technology in computer science education (2008)

In this paper, programs for capacity building in computer science education of developing countries are being compared in terms of: the type of framework implemented; its advantages and disadvantages; the influence of societal issues and language on the perceived success of the framework and finally how the technology used for communication, influence the success of the program. Since both researchers are actively engaged in four of the projects, participative observation is the preferred qualitative research methodology used. We have found that: each framework has different benefits; many of the challenges are consistent across many less technologically developed countries; and that improved communication technologies make it easier to have alliances and support between computer science departments at universities on different continents. This paper is a report on research currently in progress.
Generalizations of Pixel-Value Differencing Steganography for Data Hiding in Images
Authors: Jen-Chang Liu, Ming-Hong Shih
Venue: Fundamenta Informaticae (2008)

Generalizations of the pixel-value differencing (PVD) method for data hiding in graylevel images are proposed. Two extensions of the PVD method are analyzed: the block-based approach and the Haar-based approach. For the block-based PVD, the cover image is divided into non-overlapping horizontal or square blocks of n pixels. In each block, n &minus; 1 differences are calculated between consecutive pixels. These differences are classified to embed the secret message. For the Haar-based PVD, the 2-D integer Haar wavelet is applied to decomposed the cover image. The high-frequency components are used to hide message. Higher level of Haar decomposition allows more bits to be embedded. For both proposed generalizations, the capacity of the embeddedmessage is significantly increased. Moreover, both generalizations are invulnerable to the RS-diagram and histogram steganalysis.
Sketching concurrent data structures
Authors: Armando Solar-Lezama, Christopher Grant Jones, Rastislav Bodik
Venue: Proceedings of the 2008 ACM SIGPLAN conference on Programming language design and implementation (2008)

We describe PSketch, a program synthesizer that helps programmers implement concurrent data structures. The system is based on the concept of sketching, a form of synthesis that allows programmers to express their insight about an implementation as a partial program: a sketch. The synthesizer automatically completes the sketch to produce an implementation that matches a given correctness criteria. PSketch is based on a new counterexample-guided inductive synthesis algorithm (CEGIS) that generalizes the original sketch synthesis algorithm from Solar-Lezama et.al. to cope efficiently with concurrent programs. The new algorithm produces a correct implementation by iteratively generating candidate implementations, running them through a verifier, and if they fail, learning from the counterexample traces to produce a better candidate; converging to a solution in a handful of iterations. PSketch also extends Sketch with higher-level sketching constructs that allow the programmer to express her insight as a "soup" of ingredients from which complicated code fragments must be assembled. Such sketches can be viewed as syntactic descriptions of huge spaces of candidate programs (over 108 candidates for some sketches we resolved). We have used the PSketch system to implement several classes of concurrent data structures, including lock-free queues and concurrent sets with fine-grained locking. We have also sketched some other concurrent objects including a sense-reversing barrier and a protocol for the dining philosophers problem; all these sketches resolved in under an hour.
Effective on-line algorithms for reliable due date quotation and large-scale scheduling
Authors: Philip Kaminsky, Zu-Hsu Lee
Venue: Journal of Scheduling (2008)

We consider the sequencing of a series of jobs that arrive at a single processor over time. At each job's arrival time, a due date must be quoted for the job, and the job must complete processing before its quoted due date. The objective is to minimize the sum (or average) of quoted due dates, or equivalently, the average quoted lead time. In this paper, we propose on-line heuristics for this problem and characterize the conditions under which these heuristics are asymptotically optimal. Computational testing further demonstrates the relative effectiveness of these heuristics under various conditions.