ppxscal/embedding_network huggingface dataset:
Study of content-based image retrieval using parallel computing technique
Authors: Yongquan Lu, Pengdong Gao, Rui Lv, Zhiwu Su, Wenhua Yu
Venue: Proceedings of the 2007 Asian technology information program's (ATIP's) 3rd workshop on High performance computing in China: solution approaches to impediments for high performance computing (2007)

In this paper, we implement a parallel technique to a content-based image retrieval system and investigate the influence of different hardware devices on the retrieval system performance. Our system is developed on cluster architecture. The feature extraction and similarity comparison of visual features, which are widely used for the content-based image retrieval, are realized by using the parallel computing technique. Therein, the feature vector, which identifies one image uniquely, is composed of several different color features. Numerical experiments have demonstrated that the parallel computing techniques can be applied to significantly improve the performance of retrieval system.
Enhancing the general background of CS students through a computing history course
Authors: Paolo Giangrandi, Claudio Mirolo
Venue: Proceedings of the 13th annual conference on Innovation and technology in computer science education (2008)

The Italian Association of Automatic Computing (AICA) promotes the introduction of academic courses on the computing history. Also the University of Udine participates in this project by offering an elective course in the CS and IT programs. After the first two years of this new experience, we attempt to outline what is emerging from the analysis of the students' answers to a couple of specifically designed questionnaires and to the examination tests. A major point of interest is that the course helps us to get some insight on our students' general background and attitude toward culture. In particular, the first observations seem to indicate that they are rather curious about the technological artifacts, but come with a poor historical picture and then have difficulty putting science and technology in a historical perspective. Although our analysis reveals some positive trends, it is not easy to assess the course effectiveness in this respect because of the lack of suitable benchmarks.
Mobile spatial audio interfaces
Authors: Owen Noel Newton Fernando, Michael Cohen, Adrian David Cheok
Venue: Proceedings of the 9th international conference on Human computer interaction with mobile devices and services (2007)

For an increasing amount of people (especially young people), the mobile phone, and not the computer, is becoming their main media device and portal to the virtual world. Mobile phones have become a ubiquitous technology and for many people an important tool for communication and information access. Mobile telephony offers an interesting platform for building multipresence-enabled applications that utilize the phone as a social or commercial assistant. The main objective of this research is to develop multipresence-enabled audio windowing systems for visualization, attention, and privacy awareness of narrowcasting (selection) functions in collaborative virtual environments (CVEs) for mobile devices such as 3rd- and 4th-generation mobile phones. Mobile audio windowing system enhances auditory information on mobile phones and encourages modernization of office- and mobile-based conferencing.
Applying telepresence to incident management: The virtual incident command center
Authors: Julius S. Gyorfi Eric R. Buhrke Mark A. Tarlton Juan M. Lopez George T. Valliath
Venue: Presence: Teleoperators and Virtual Environments (2008)

This paper describes an application of telepresence technology to the incident management domain. The system combines national guidelines for incident management with many aspects of collaborative virtual environments to enable effective communication between first responders in the field and remotely located command personnel. A brief overview of existing incident management systems is given, followed by a set of requirements for future systems. We then describe our virtual incident command center (VICC) prototype, explain how it addresses the requirements, and outline our future plans. Finally, we report feedback from ongoing demonstrations of the prototype system that supports our contention that VICC represents a unique solution to the incident management problem.
Sprouting search-an algorithmic framework for asynchronous parallel unconstrained optimization
Authors: árpád Bhurmen, Tadej Tuma
Venue: Optimization Methods Software (2007)

Direct search optimization algorithms are becoming an important alternative to well-established gradient based methods. Due to the fact that a single cost function evaluation may take a substantial amount of time, optimization can be a lengthy process. In order to shorten the run time one often resorts to parallel algorithms. Asynchronous algorithms are particularly efficient since they have no synchronization points. This paper is an attempt to establish a convergence theory for a class of such parallel direct search algorithms. The notion of a search direction generator (SDG) is introduced. An algorithmic framework for parallel distributed optimization methods based on SDGs is presented along with the corresponding convergence theory. The theory almost completely decouples the stepsize control from the sufficient descent requirement, which is necessary for the finite termination of the algorithm's inner loop. The proposed framework has several attributes considered very favourable in loosely coupled parallel systems (e.g. clusters of workstations), such as fault tolerance and scalability. The framework is illustrated by optimizing a set of test problems on a cluster of workstations. In all tested cases, a speedup was obtained that increased with the increasing number of workstations. Fault tolerance and scalability of the framework were also demonstrated by removing and adding workstations to the cluster while an optimization run was in progress.
QoS in wireless sensor networks: survey and approach
Authors: José-F Martínez, Ana-B Garcí, Iván Corredor, Lourdes López, Vicente Hernández, Antonio Dasilva
Venue: Proceedings of the 2007 Euro American conference on Telematics and information systems (2007)

A wireless sensor network (WSN) is a computer wireless network composed of spatially distributed and autonomous tiny nodes -- smart dust sensors, motes -, which cooperatively monitor physical or environmental conditions. Nowadays these kinds of networks support a wide range of applications, such as target tracking, security, environmental control, habitat monitoring, source detection, source localization, vehicular and traffic monitoring, health monitoring, building and industrial monitoring, etc. Many of these applications have strong requirements for end-to-end delay and losses during data transmissions. In this work we have classified the main mechanisms that have been proposed to provide Quality of Service (QoS) in WSN at Medium Access Control (MAC) and network layers. Finally, taking into account some particularities of the studied MAC- and network-layer protocols, we have selected a real application scenario in order to show how to choose an appropriate approach for guaranteeing performance in a WSN deployed application.
Searching blogs and news: a study on popular queries
Authors: Aixin Sun, Meishan Hu, Ee-Peng Lim
Venue: Proceedings of the 31st annual international ACM SIGIR conference on Research and development in information retrieval (2008)

Blog/news search engines are very important channels to reach information about the real-time happenings. In this paper, we study the popular queries collected over one year period and compare their search results returned by a blog search engine (i.e., Technorati) and a news search engine (i.e., Google News). We observed that the numbers of hits returned by the two search engines for the same set of queries were highly correlated, suggesting that blogs often provide commentary to current events reported in news. As many popular queries are related to some events, we further observed a high cohesiveness among the returned search results for these queries.
Estimation of semi-sparse radar range profiles
Authors: Yngve Selén, Petre Stoica
Venue: Digital Signal Processing (2008)

We study the use of semi-sparse models, i.e., models having a few coefficients that are significantly larger than the rest, for estimation of range profiles in radar and other active sensing applications. The estimation of such range profiles is equivalent to estimation of a vector of regression coefficients in an underdetermined linear system. Each coefficient corresponds to a certain range bin in the illuminated area. If a range bin contains a target the reflections from that bin will, in some applications, result in a value of the corresponding coefficient which is significantly larger than the value corresponding to a target-free range bin. Under the assumption of a mixture of semi-sparse linear Gaussian models, we derive the minimum mean square error (MMSE) estimate of the range profile. We then find computationally efficient approximations of this MMSE estimate. As a by-product we also obtain a maximum a posteriori (MAP) target detector that does not require the choice of any detection threshold. The performances of our methods are illustrated via numerical examples.
Recovery of Encryption Keys from Memory Using a Linear Scan
Authors: Christopher Hargreaves, Howard Chivers
Venue: Proceedings of the 2008 Third International Conference on Availability, Reliability and Security (2008)

As encrypted containers are encountered more frequently the need for live imaging is likely to increase. However, an acquired live image of an open encrypted file system cannot later be verified against any original evidence, since when the power is removed the decrypted contents are no longer accessible. This paper shows that if a memory image is also obtained at the same time as the live container image, by the design of on-the-fly encryption, decryption keys can be recovered from the memory dump. These keys can then be used offline to gain access to the encrypted container file, facilitating standard, repeatable, forensic file system analysis. The recovery method uses a linear scan of memory to generate trial keys from all possible memory positions to decrypt the container. The effectiveness of this approach is demonstrated by recovering TrueCrypt decryption keys from a memory dump of a Windows XP system.
Conductivity Reconstruction of Brain Edema Based on Improved Adaptive Genetic Algorithm
Authors: Jicheng Liu, Kama Huang, Yayi Hu, Qing Chen
Venue: Proceedings of the 2008 International Conference on BioMedical Engineering and Informatics - Volume 02 (2008)

In order to estimate the progression or regression of edema at the bedside continuously, based the theoretic model, an improved Adaptive Genetic Algorithm(AGA) has been applied in optimization of conductivity reconstruction. Dynamic crossover and mutation operators, which are based on Haiming Distance, are brought forward in this paper to maintain generation’s diversity. As a contrast, the Simple GA(SGA) has also been applied in same optimization of brain edema. It is shown the AGA not only has satisfied efficiency but also has enhanced the capability to converge to the best answer.
Facilitating a Well-Founded Approach to Autonomic Systems
Authors: Simon Dobson
Venue: Proceedings of the Fifth IEEE Workshop on Engineering of Autonomic and Autonomous Systems (2008)

While it is desirable for all computing and communications systems to have well-defined and verifiable behaviour, autonomic systems must additionally guarantee that their adaptive behaviour is correct, both in the sense of responding appropriately to changes in context and in the sense of continuing to meet the high-level requirements of the system. Ensuring such high levels of "process" correctness poses a significant challenge for system designers. Formal methods provide a valuable tool to assist in the design, analysis and verification processes. The goals of the ACF’s semantics working group is to identify formal techniques that may be applicable to the development of autonomic systems, and to promote the understanding of these techniques within the research community.
Serializable isolation for snapshot databases
Authors: Michael J. Cahill, Uwe Röhm, Alan D. Fekete
Venue: Proceedings of the 2008 ACM SIGMOD international conference on Management of data (2008)

Many popular database management systems offer snapshot isolation rather than full serializability. There are well-known anomalies permitted by snapshot isolation that can lead to violations of data consistency by interleaving transactions that individually maintain consistency. Until now, the only way to prevent these anomalies was to modify the applications by introducing artificial locking or update conflicts, following careful analysis of conflicts between all pairs of transactions. This paper describes a modification to the concurrency control algorithm of a database management system that automatically detects and prevents snapshot isolation anomalies at runtime for arbitrary applications, thus providing serializable isolation. The new algorithm preserves the properties that make snapshot isolation attractive, including that readers do not block writers and vice versa. An implementation and performance study of the algorithm are described, showing that the throughput approaches that of snapshot isolation in most cases.
Error estimates for abstract linear---quadratic optimal control problems using proper orthogonal decomposition
Authors: M. Hinze, S. Volkwein
Venue: Computational Optimization and Applications (2008)

In this paper we investigate POD discretizations of abstract linear---quadratic optimal control problems with control constraints. We apply the discrete technique developed by Hinze (Comput. Optim. Appl. 30:45---61, 2005) and prove error estimates for the corresponding discrete controls, where we combine error estimates for the state and the adjoint system from Kunisch and Volkwein (Numer. Math. 90:117---148, 2001; SIAM J. Numer. Anal. 40:492---515, 2002). Finally, we present numerical examples that illustrate the theoretical results.
SecCOSEn - A Key Management Scheme for Securing Chain Oriented Sensor Networks
Authors: Quazi Ehsanul Kabir Mamun, Sita Ramakrishnan
Venue: Proceedings of the Communication Networks and Services Research Conference (2008)

Resource-constraint nature of Wireless Sensor Network (WSN) turns the security issue certainly into a big challenge. An efficient key management scheme is the pre-requisite to ensure security in WSN. In this paper we present two versions of a secured key management protocol (SecCOSEN) adopted on COSEN, a chain oriented sensor network, which is used for periodic data collection. SecCOSEN uses partial key pre-distribution and symmetric crypto-graphy techniques. Where as one version of SecCOSEN protocol uses shared partial keys in a sensor chain the other version uses private partial keys. Both versions of SecCOSEN show high resilience to different security attacks. The protocol outperforms other random key pre-distribution protocols in the sense that it requires lower space, lower communication overhead and offers very high session key candidates. A comparative discussion between the two versions is also provided.
Approximate algorithms for credal networks with binary variables
Authors: Jaime Shinsuke Ide, Fabio Gagliardi Cozman
Venue: International Journal of Approximate Reasoning (2008)

This paper presents a family of algorithms for approximate inference in credal networks (that is, models based on directed acyclic graphs and set-valued probabilities) that contain only binary variables. Such networks can represent incomplete or vague beliefs, lack of data, and disagreements among experts; they can also encode models based on belief functions and possibilistic measures. All algorithms for approximate inference in this paper rely on exact inferences in credal networks based on polytrees with binary variables, as these inferences have polynomial complexity. We are inspired by approximate algorithms for Bayesian networks; thus the Loopy 2U algorithm resembles Loopy Belief Propagation, while the Iterated Partial Evaluation and Structured Variational 2U algorithms are, respectively, based on Localized Partial Evaluation and variational techniques.
Testing an Interrelationship Matrix-Based Method Designed for Assisting in e-Marketplace Selection
Authors: John L. Hopkins, Dennis F. Kehoe
Venue: Electronic Markets (2007)

Over the past decade an extraordinary increase has been experienced in the practice of B2B online trading. Portals, hubs, brokerages, and in particular electronic marketplaces (e-marketplaces) have emerged as everyday channels for business trading. The decision process behind joining such an e-marketplace, and evaluating which particular ones offer the best mix of services for a particular business's requirements, is not a straightforward undertaking. There are a host of variants on offer, numerous different membership schemes, service ranges, functionality types, product ranges, and technology platforms in existence, so it can prove to be a very confusing process for any prospective company contemplating joining. In earlier work (Hopkins and Kehoe 2006) an interrelationship matrix-based method was developed for evaluating, and rating, the appropriateness of a range of services offered by e-marketplaces in comparison with specific customer requirements. The system was designed to be used not only for evaluating existing e-marketplaces, but also in assisting with the design of new ones, and was intended be of equal value to both buyers and sellers. This paper now describes how the developed system has been tested, in two case study environments, in order to gauge its suitability for e-marketplace evaluation at both component level and sector level.
Automated anthropometric data collection using 3D whole body scanners
Authors: Jun-Ming Lu, Mao-Jiun J. Wang
Venue: Expert Systems with Applications: An International Journal (2008)

The development of three-dimensional (3D) whole body scanner opens opportunities for measuring human body more efficiently. While taking measurements from 3D scanning data, markers are usually placed on human body to facilitate landmarking and data collection. But the procedure of placing markers is very tedious and may involve human errors. The objective of this study is to develop an automated anthropometric data collection system to eliminate manual intervention. For 3D image analysis, the first step is to segment the body parts by analyzing the 2D silhouette. Then we use the approximate location estimates as the references for performing initial searches of the landmarks. Subsequently, four algorithms including silhouette analysis, minimum circumference determination, gray-scale detection, and human-body contour plots are developed to extract 12 landmarks and three characteristic lines on human body. Finally, from the results of automated landmarking, 104 anthropometric data can be obtained. To evaluate the validity and reliability of the automated anthropometric data collection system, 189 human subjects were scanned and the scanning data were processed by the system. The results demonstrated that the system was very effective and robust. Based on the newly developed system, many applications can be extended.
Trends in Security Product Evaluations
Authors: Richard E. Smith
Venue: Information Systems Security (2007)

Government-endorsed security evaluations, like those performed under the Common Criteria (CC), use established techniques of software quality assurance to try to evaluate product security. Despite high costs and disputed benefits, the number of evaluated products has grown dramatically since 2001, doubling between 2003 and 2005 and leaping again in 2006. Using details from more than 860 security evaluations, this paper looks at the types of products evaluated, the "assurance levels" achieved, where the evaluations occur, and ongoing participation by product vendors. These observations are combined with other lessons learned to make recommendations on product evaluation strategies.
A class of logic problems solvable by linear programming
Authors: M. Conforti
Venue: Proceedings of the 33rd Annual Symposium on Foundations of Computer Science (1992)

Several problems of propositional logic, such as satisfiability, MAXSAT and logical inference, can be formulated as integer programs. The authors consider sets of clauses for which these integer programs can be solved as linear programs. They prove that balanced sets of clauses have this property.
Space-time opportunities for multiple agents: a constraint-based approach
Authors: T. Neutens, F. Witlox, N. Van De Weghe, P. H. De Maeyer
Venue: International Journal of Geographical Information Science (2007)

Constraint-based models and models constructing accessibility measures mainly focus on single agents having only one available transport mode. However, numerous cases exist where multiple agents or groups of individuals with different available transport modes want to participate in a joint activity at a certain location. The aim of this paper is to provide new insights into representing and reasoning about feasible space-time opportunities for multiple agents. Relying on concepts of time geography, we propose a conceptual framework in order to determine interaction spaces for groups of individuals. Besides availability of means of transport and the locations of each individual, minimum activity duration and opening hours of opportunities are taken into account. The reasoning about space and time is visualized in three dimensions using a hybrid (CAD/GIS) system.
A Federated Physical and Logical Access Control Enforcement Model
Authors: Stéphane Onno
Venue: Proceedings of the 2008 Third International Conference on Availability, Reliability and Security (2008)

This paper addresses the confidentiality of valuable content while the content is being accessed. Confidentiality threats such as information leakage by shoulder surfing or content theft may occur on critical assets. A person having access to a protected zone may therefore access to content which is unauthorized to him. This could be disastrous for the information of a top secret document or for a valuable digital film. An unprotected content could be attacked in two conditions: one if a protected content can be accessed without protected zone access restrictions or second if a protected zone can be accessed without logical access restrictions. To tackle these threats, this paper proposes a Federated Physical and Logical Access Control Enforcement Model. The model enforces a protected zone access control for logical content access together with a content-based access control for physical zone access. The access authorizations to content and to zone are dynamically linked together. Accordingly, it ensures that at every moment, contents currently edited can be processed by any user inside the protected zone. A formalized model example enforces a global Bell-Lapadula policy for a protected zone. Applicability is discussed for post-production film facilities and high sensitive protected zones such as government or defense facilities.