ppxscal/embedding_network huggingface dataset:
Markov-Based OVSF Code Assignment Scheme and Call Admission Control for Wideband-CDMA Communication Systems
Authors: Ben-Jye Chang, Min-Xiou Chen, Ren-Hung Hwang, Chun-Huan Chuang
Venue: Wireless Personal Communications: An International Journal (2005)

For the reason of the orthogonal characteristic of the Orthogonal Variable Spreading Factor (OVSF) code tree in Wideband CDMA (WCDMA) systems, code blocking increases as traffic load (i.e. Erlang load) or the required rate increases. This causes inefficient utilization of channelization codes. Hence, how to efficiently manage the resource of channelization codes of the OVSF code tree in WCDMA systems is an important issue and has been studied extensively. There are two aspects to achieve efficiency including code assignment and code reassignment. In the aspect of code assignment, an efficient code assignment scheme reduces code blocking probability significantly. In the aspect of code reassignment, code reassignment results in several drawbacks, such as large overhead of computation, high complexity of codes moving, and long call setup time for a new request call, etc. Therefore, in this paper we focus on the first aspect of how to efficiently assign the channelization codes. Additionally, most researches did not consider the analysis of tree state with dynamic traffic load and their analysis lack of systematic call admission control (CAC) mechanism. Therefore, in this paper, we first propose the Markov decision process (MDP) based analysis to assign channelization codes efficiently. Next, we extend the MDP-based approach as the call admission control mechanism to maximize the system revenue while reducing blocking probability. Furthermore, a bit string masking algorithm is proposed to reduce the time complexity of tree managing and searching for available channelization codes. Numerical results indicate that the proposed MDP approach yields the best fractional reward loss, code blocking reward loss, and code blocking ratio as compared to that of other schemes, including the random, left most, and crowded first schemes.
Concept-Based Term Weighting for Web Information Retrieval
Authors: John Zakos, Brijesh Verma
Venue: Proceedings of the Sixth International Conference on Computational Intelligence and Multimedia Applications (2005)

In this paper we present a novel technique for determining term importance by exploiting concept-based information found in ontologies. Calculating term importance is a significant and fundamental aspect of most information retrieval approaches and it is traditionally determined through inverse document frequency (IDF). We propose concept-based term weighting (CBW), a technique that is fundamentally different to IDF in that it calculates term importance by intuitively interpreting the conceptual information in ontologies. We show that when CBW is used in an approach for web information retrieval on benchmark data, it performs comparatively to IDF, with only a 3.5% degradation in retrieval accuracy. While this small degradation has been observed the significance of this technique is that 1) unlike IDF, CBW is independent of document collection statistics, 2) it presents a new way of interpreting ontologies for retrieval, and 3) it introduces an additional source of term importance information that can be used for term weighting.
Security of Critical Control Systems Sparks Concern
Authors: David Geer
Venue: Computer (2006)

Internet connectivity can make operations more convenient, but it also can leave critical industrial control systems vulnerable to the same attacks that threaten other online activities.
Secure off-the-record messaging
Authors: Mario Di Raimondo, Rosario Gennaro, Hugo Krawczyk
Venue: Proceedings of the 2005 ACM workshop on Privacy in the electronic society (2005)

At the 2004 Workshop on Privacy in the Electronic Society (WPES), Borisov, Goldberg and Brewer, presented "Off the Record Messaging" (OTR), a protocol designed to add end-to-end security and privacy to Instant Messaging protocols. An open-source implementation of OTR is available and has achieved considerable success.In this paper we present a security analysis of OTR showing that, while the overall concept of the system is valid and attractive, the protocol suffers from security shortcomings due to the use of an insecure key-exchange protocol and other problematic design choices.On the basis of these findings, we propose alternative designs and improvements that strengthen the security of the system and provide the originally intended features of the protocol, including deniability, in a sound and well-defined sense.
VETO - Enabling a P2P-based Market for Composed Servic
Authors: Jan Gerke, Burkhard Stiller
Venue: Proceedings of the The IEEE Conference on Local Computer Networks 30th Anniversary (2005)

Service-oriented peer-to-peer architectures combine the benefits of service-oriented architectures and peer-to-peer networks, such as loose coupling and scalability. They also support service composition, the combining of existing services into new ones. Until now, only composition service strategies for a single peer acting as a service composer have been investigated. Therefore, this paper investigates the market for composed services. It is shown that this market forms an oligopoly and, thus, requires incentive-compatible service pricing. In consequence, the vickrey procurement auction VETO has been developed determining the pricing mechanism in a fully distributed manner. It is proven that VETO is incentive-compatible and maximizes the market's welfare. Furthermore, the VETO protocol is specified and it is shown that this protocol prevents collusion within the auction. Still, VETO upholds the peer-to-peer paradigm by only relying on the peers which are taking part in the auction, no additional trusted entities or super-peers are required.
Overcoming Limitations of Approximate Query Answering in OLAP
Authors: Alfredo Cuzzocrea
Venue: Proceedings of the 9th International Database Engineering & Application Symposium (2005)

Two important limitations of approximate query answering in OLAP are recognized and investigated. These limitations are: (i) scalability of the techniques, i.e. their reliabiliy on highly-dimensional data cubes, and (ii) need for guarantees on the degree of approximation of the answers. In this paper, we focus on the first limitation, and propose adopting the well-known Karhunen-Loeve Transform (KLT) to obtain dimensionality reduction of data cubes, thus devising a transformation methodology that is independent by the number of dimensions of the data cubes. To tailor the KLT for the specific OLAP context, effective optimizations are also proposed, by taking into account the query-consciousness feature. Finally, some encouraging preliminary experimental results are presented.
The Fast Fourier Transform for Experimentalists, Part V: Filters
Authors: Denis Donnelly
Venue: Computing in Science and Engineering (2006)

This fifth segment in what has turned out to be a six-part series on the fast Fourier transform (FFT) will be the last to deal solely with methods or ideas associated with the transform process itself.
Automatically Identifying Special and Common Unit Tests for Object-Oriented Programs
Authors: Tao Xie, David Notkin
Venue: Proceedings of the 16th IEEE International Symposium on Software Reliability Engineering (2005)

Developers often create common tests and special tests, which exercise common behaviors and special behaviors of the class under test, respectively. Although manually created tests are valuable, developers often overlook some special or even common tests. We have developed a new approach for automatically identifying special and common unit tests for a class without requiring any specification. Given a class, we automatically generate test inputs and identify common and special tests among the generated tests. Developers can inspect these identified tests and use them to augment existing tests. Our approach is based on statistical algebraic abstractions, program properties (in the form of algebraic specifications) dynamically inferred based on a set of predefined abstraction templates. We use statistical algebraic abstractions to characterize program behaviors and identify special and common tests. Our initial experience has shown that a relatively small number of common and special tests can be identified among a large number of generated tests and these identified tests expose common and special behaviors that deserve developers' attention.
SVM Feature Selection for Classification of SPECT Images of Alzheimer's Disease Using Spatial Information
Authors: Jonathan Stoeckel, Glenn Fung
Venue: Proceedings of the Fifth IEEE International Conference on Data Mining (2005)

Alzheimer's disease is the most frequent type of dementia for elderly patients. Due to aging populations the occurrence of this disease will increase in the next years. Early diagnosis is crucial to be able to develop more powerful treatments. Brain perfusion changes can be a marker for Alzheimer's disease. In this article we study the use of SPECT perfusion imaging for the diagnosis of Alzheimer's disease differentiating between images from healthy subjects and images from Alzheimer's disease patients. Our classification approach is based on a linear programming formulation similar to the 1-norm support vector machines. In contrastwith other linear hyperplane-based methods that perform simultaneous feature selection and classification, our proposed formulation incorporates proximity information about the features and generates a classifier that does not just select the most relevant voxels but the most relevant "areas" for classification resulting in more robust classifiersthat are better suitable for interpretation. This approach is compared with the classical Fisher linear discriminant (FLD) classifier as well as with statistical parametric mapping (SPM). We tested our method on data from four European institutions. Our method achieved sensitivity of 84.4% at 90.9% specificity, this is considerable better the human experts. Our method also outperformed the FLD and SPM techniques. We conclude that our approach has the potential to be a useful help for clinicians.
Tracking Human Breath in Infrared Imaging
Authors: Zhen Zhu, Jin Fei, Ioannis Pavlidis
Venue: Proceedings of the Fifth IEEE Symposium on Bioinformatics and Bioengineering (2005)

In this paper, we propose a novel tracker to capture the human breathing signal through an infrared imaging method. Human facial physiology information is used to select salient thermal features on the human face as good features to track. The major component of the tracker is Mean Shift Localization (MSL)-based particle filtering. A special measurement model is designed for particle filtering so that the tracker can handle significant head movement and object occlusion. The breathing signal is achieved based on tracking results. The experiments show that the tracker is robust and stable and the recovered breathing signal is clear enough for breathing functionality computation.
A Social and Physical Inter-Generational Computer Game for the Elderly and Children: Age Invaders
Authors: Adrian David Cheok, ShangPing Lee, Sameera Kodagoda, Khoo Eng Tat, Le Nam Thang
Venue: Proceedings of the Ninth IEEE International Symposium on Wearable Computers (2005)

The cultural gap between the young and the old has been enlarging in our modern age, especially with respect to the use and adoption of technology. Children nowadays enjoy playing computer games while there is very little participation by the elderly in this entertainment area. This paper introduces "Age Invaders", a novel game which allows the elderly to play harmoniously together with children in physical space. The system also allows natural social-physical interactions amongst generations, both physically and through the internet.
Differential Deserialization for Optimized SOAP Performance
Authors: Nayef Abu-Ghazaleh, Michael J. Lewis
Venue: Proceedings of the 2005 ACM/IEEE conference on Supercomputing (2005)

SOAP, a simple, robust, and extensible protocol for the exchange of messages, is the most widely used communication protocol in the Web services model. SOAP's XML-based message format hinders its performance, thus making it unsuitable in high-performance scientific applications. The deserialization of SOAP messages, which includes processing of XML data and conversion of strings to in-memory data types, is the major performance bottleneck in a SOAP message exchange. This paper presents and evaluates a new optimization technique for removing this bottleneck. This technique, called differential deserialization (DDS), exploits the similarities between incoming messages to reduce deserialization time. Differential deserialization is fully SOAPcompliant and requires no changes to a SOAP client. A performance study demonstrates that DDS can result in a significant performance improvement for some Web services.
On-Line Signature Verification With Two-Stage Statistical Models
Authors: Liang Wan, Bin Wan
Venue: Proceedings of the Eighth International Conference on Document Analysis and Recognition (2005)

Signature verification is a challenging task, because only a small set of genuine samples can be acquired and usually no forgeries are available in real application. In this paper, we propose a new two-stage statistical system for automatic on-line signature verification. Our system is composed of a simplified GMM model for global signature features, and a discrete HMM model for local signature features. To be practical, we introduce specific simplification strategies for model building and training. Our system requires only 5 genuine samples for new users and relies on only 3 global parameters for quick and efficient system tuning. Experiments are conducted to verify the effectiveness of our system.
RACE on a Physically Distributed and Logically Shared Memory System
Authors: Seongwoon Kim, Ando Ki, Bogwan Kim
Venue: Proceedings of the 18th International Conference on Systems Engineering (2005)

The RACE (Remote Access Cache coherency Enforcement) protocol is a cache coherency protocol that uses a full-mapped directory-based cache protocol to provide a consistent memory through multi-level memory hierarchy consisting of a number of processor caches, physically distributed shared-memory, and third level caches. In this paper, we have proposed a RACE protocol which can be used in the physically distributed and logically shared memory system.
Layer-2 Mobility Management in HybridWired/Wireless Systems
Authors: Jidong Wang, Lichun Bao
Venue: Proceedings of the Second International Conference on Quality of Service in Heterogeneous Wired/Wireless Networks (2005)

In hybrid wired and wireless systems, mobile hosts constantly changes points of attachment to the wired networks, causing frequent disruptions to the ongoing network traffic. An infrastructure supported approach is required to meet the stringent delay and jitter requirements in non-disrupted services. We propose a mobility management scheme, called Personal AP, to support seamless roaming. In Personal AP systems, the network attachment information, i.e., the association states, of a mobile station is extracted, and handed off from one physical access point to another along with the mobile station, thus eliminating the mobile station from reassociating with new access points. Simulation results show that Personal AP can greatly reduce the handoff latencies, and is suitable to support delay-sensitive multimedia applications.
State complexity of linear conjunctive languages
Authors: Alexander Okhotin
Venue: Journal of Automata, Languages and Combinatorics (2004)

The ε-free languages generated by linear conjunctive grammars have recently been proved to be exactly the languages accepted by trellis automata. This paper begins the study of the descriptional complexity of this language family by comparing the number of states in automata with the size of grammars. The state complexity of the languages (aC)+ and {an(bCn)+ | n ≥ 1} is determined (it is C and C + 3 respectively), leading to an exact expression for the worst-case complexity of all set-theoretic operations and to the non-uniqueness of minimal automata. A superpolynomial lower bound and an exponential upper bound for the succinctness tradeoff between linear conjunctive grammars and trellis automata are established.
An Algorithm for In-Core Frequent Itemset Mining on Streaming Data
Authors: Ruoming Jin, Gagan Agrawal
Venue: Proceedings of the Fifth IEEE International Conference on Data Mining (2005)

Frequent itemset mining is a core data mining operation and has been extensively studied over the last decade. This paper takes a new approach for this problem and makes two major contributions. First, we present a one pass algorithm for frequent itemset mining, which has deterministic bounds on the accuracy, and does not require any out-of-core summary structure. Second, because our one pass algorithm does not produce any false negatives, it can be easily extended to a two pass accurate algorithm. Our two pass algorithm is very memory efficient, and allows mining of datasets with large number of distinct items and/or very low support levels. Our detailed experimental evaluation on synthetic and real datasets shows the following. First, our one pass algorithm is very accurate in practice. Second, our algorithm requires significantly lower memory than Manku and Motwani's one pass algorithm and the multi-pass Apriori algorithm. Our two pass algorithm outperforms Apriori and FP-tree when the number of distinct items is large and/or support levels are very low. In other cases, it is quite competitive, with possible exception of cases where the average length of frequent itemsets is quite high.
Dual Purpose Multi-User Semi-Immersive Hapto-Acoustic Virtual Environment
Authors: Tony Adriaansen
Venue: Proceedings of the Digital Image Computing on Techniques and Applications (2005)

Our hapto-acoustic virtual environment we call the "haptic-workbench" [1], has remained unchanged since 1994. Recent changes in available projector hardware technology now means that the system can be modified to address some inherent limitations in terms of user participation. In addition, the proposed changes are now more viable, whereas only six months ago such modifications were prohibitively expensive or not possible. Up to now the system has used active stereo for 3D graphics visualization but this implementation limits effective participation to one person. The new dual purpose environment is a more versatile system which may be used in one of two ways; a) single user mode or b) large volume display mode where many users can simultaneously participate. The semi-immersive attributes of the former haptic-workbench are retained in single user mode and when in large volume display mode the system allows multiple user involvement and interaction. The new dual purpose multi-user environment removes some of the restrictions which effectively limit interaction to one person operating in a narrow viewing space, is not limited to rooms needing special seating or lighting and addresses the increasing need for a sense of presence and interaction with many persons simultaneously. Groups of up to 30 can now experience the collaborative virtual environment (CVE) [2] rather than single user at a time and when networked allows the system to be used for educational interaction in a classroom setting with the possibility of similar numbers at each end. Methodology and some traps and pitfalls are discussed in terms of differing technologies used in generating the real time 3D stereo models and the realisation of the new system is given.
A Multi-point Distributed Random Variable Accelerator for Monte Carlo Simulation in Finance
Authors: Nicola Bruti Liberati, Filippo Martini
Venue: Proceedings of the 5th International Conference on Intelligent Systems Design and Applications (2005)

The pricing and hedging of complex derivative securities via Monte Carlo simulations of stochastic differential equations constitutes an intensive computational task. To achieve "real time" execution, as often required by fi- nancial institutions, one needs highly efficient implementations of the multi-point distributed random variables underlying the simulations. In this paper a fast and flexible dedicated hardware solution is proposed. A comparative performance analysis demonstrates that the hardware solution is bottleneck-free and flexible, and significantly increases the computational efficiency of the software solution.
The Neural-based Segmentation of Cursive Words using Enhanced Heuristics
Authors: Chun Ki Cheng, Michael Blumenstein
Venue: Proceedings of the Eighth International Conference on Document Analysis and Recognition (2005)

This paper presents an Enhanced Heuristic Segmenter (EHS) and an improved neural-based segmentation technique for segmenting cursive words and validating prospective segmentation points respectively. The EHS employs two new features, ligature detection and a neural assistant, to locate prospective segmentation points. The improved neural-based segmentation technique can then be used to examine the prospective segmentation points by fusion of confidence values obtained from left and centre character recognition outputs in addition to the segmentation point validation (SPV) output. The improved neural-based segmentation technique uses a recently proposed feature extraction technique (Modified Direction Feature) for representing the segmentation points and characters to enhance the overall segmentation process. The EHS and the neural-based segmentation technique have been implemented and tested on a benchmark database providing encouraging results.
Monitoring virtual memory with vmstat
Authors: Brian K. Tanaka
Venue: Linux Journal (2005)

Need to monitor performance on your systems? vmstat helps you understand when memory is the bottleneck.
A small set of axioms for residuated logic
Authors: Nehad N. Morsi
Venue: Information Sciences: an International Journal (2005)

We show that a set of three axioms, together with modus ponens, suffices to build up a formal system for the class R of all quadruples (L, ≤, T,J), in which (L,≤) is a partially ordered set with a top element, and T is a triangular norm on (L,≤) that has a residuated implication J. We show that this R is not a variety.
Investigating the Anomalous States of Knowledge hypothesis in a real-life problem situation: A study of history and psychology undergraduates seeking information for a course essay: Research Articles
Authors: Charles Cole, John Leide, Jamshid Beheshti, Andrew Large, Martin Brooks
Venue: Journal of the American Society for Information Science and Technology (2005)

The authors present a study of the real-life information needs of 59 McGill University undergraduates researching essay topics for either a history or psychology course, interviewed just after they had selected their essay topic. The interview's purpose was to transform the undergraduate's query from general topic terms, based on vague conceptions of their essay topic, to an information need-based query. To chart the transformation, the authors investigate N. J. Belkin, R. N. Oddy, and H. M. Brooks' Anomalous States of Knowledge (ASK) hypothesis (1982a, 1982b), which links the user's ASK to a relevant document set via a common code based on structural facets. In the present study an interoperable structural code based on eight essay styles is created, then notions of structural facets compatible with a high-impact essay structure are presented. The important findings of the study are: (a) the undergraduates' topic statements and terms derived from it do not constitute an effective information need statement because for most of the subjects in the study the topic terms conformed to a low-impact essay style; (b) essay style is an effective interoperable structural code for charting the evolution of the undergraduate's knowledge state from ASK to partial resolution of the ASK in an information need statement. &copy; 2005 Wiley Periodicals, Inc.