ppxscal/embedding_network huggingface dataset:
On balking from an empty queue
Authors: Moshe Haviv, Yoav Kerner
Venue: Queueing Systems: Theory and Applications (2007)

The intuition while observing the economy of queueing systems, is that one's motivation to join the system, decreases with its level of congestion. Here we present a queueing model where sometimes the opposite is the case. The point of departure is the standard first-come first-served single server queue with Poisson arrivals. Customers commence service immediately if upon their arrival the server is idle. Otherwise, they are informed if the queue is empty or not. Then, they have to decide whether to join or not. We assume that the customers are homogeneous and when they consider whether to join or not, they assess their queueing costs against their reward due to service completion. As the whereabouts of customers interact, we look for the (possibly mixed) join/do not join Nash equilibrium strategy, a strategy that if adopted by all, then under the resulting steady-state conditions, no one has any incentive not to follow it oneself. We show that when the queue is empty then depending on the service distribution, both `avoid the crowd' (ATC) and `follow the crowd' (FTC) scenarios (as well as none-of-the-above) are possible. When the queue is not empty, the situation is always that of ATC. Also, we show that under Nash equilibrium it is possible (depending on the service distribution) that the joining probability when the queue is empty is smaller than it is when the queue is not empty.
Java Multithreading based Parallel Preconditioned Generalized Conjugate Gradient type methods
Authors: Victor N. Epitropou, Konstantinos M. Giannoutakis, George A. Gravvanis
Venue: Proceedings of the Sixth International Symposium on Parallel and Distributed Computing (2007)

A new class of Java multithreading based parallel approximate inverse preconditioning is introduced, for efficiently solving sparse arrow-type linear systems. The Parallel Explicit Preconditioned Biconjugate Conjugate Gradient - STAB method for shared memory systems is presented in order to examine the parallel behavior of this scheme using explicit approximate inverses as the suitable preconditioner. Design and implementation issues of Java's multithreading techniques are also discussed. The performance in terms of speedups and parallel efficiencies of the method, using Java multithreading, is illustrated by solving sparse arrow-type linear systems. Static and dynamic workload scheduling systems implemented in Java and the results of their use are presented and discussed.
Security Constraints in Access Control of Information System Using UML Language
Authors: Aneta Poniszewska-Maranda
Venue: Proceedings of the 15th IEEE International Workshops on Enabling Technologies: Infrastructure for Collaborative Enterprises (2006)

Process of security administration in an information system is a complex task. Many security constraints should be expressed in order to define in the proper way the security policy. The security constraints can be classified into two groups. The first group represents the constraints classified by system application and the second group the constraints required by global security policy. The application developer can define the security constraints that should by associated to the application. On the other hand, the security administrator who knows well the global security policy can set up the constraints on the global level. The objective of this paper is to present and implement the security constraints of security schema in information system based on RBAC model. The security constraints can be described using the standard tool, like the UML language and in particular one of its part - the OCL language.
Analysis of MPR Selection in the OLSR Protocol
Authors: Dang Nguyen, Pascale Minet
Venue: Proceedings of the 21st International Conference on Advanced Information Networking and Applications Workshops - Volume 02 (2007)

Mobile ad hoc networks have very attractive intrinsic qualities. However they will be adopted only if they are able to support applications with QoS requirements. They should provide a route providing the QoS requested by a flow. The OLSR routing protocol can be extended for that purpose. OLSR relies on multipoint relay (MPR) selection that has an important effect on the routing protocol's performances. Indeed, the overhead generated by the OLSR protocol and more particularly the flooding efficiency depend on MPR selection. Moreover, MPRs are used as intermediate nodes in the routes. The analysis of MPR selection presented in this paper, gives quantitative results and also takes QoS support into account. Simulations on large and dense networks show that our analysis is highly accurate.
Multi-Stage Real Time Health Monitoring via ZigBee in Smart Homes
Authors: S. Dagtas, G. Pekhteryev, Z. Sahinoglu
Venue: Proceedings of the 21st International Conference on Advanced Information Networking and Applications Workshops - Volume 02 (2007)

We present a framework for a wireless health monitoring system within a smort home using ZigBee technology. Vital signals are collected and processed using a 3-tiered architecture. The first stage is the mobile device carried on the body that runs a number of wired and wireless probes. This device is also designed to perform some basic processing such as the heart rate and fatal failure detection. At the second stage, further processing is performed by a local server using the raw data transmitted by the mobile device continuously. The raw data is also stored at this server. The processed data as well as the outcomes of the analyses are then transmitted to the service provider center for experts' review for diagnosis as well as storage. The main advantages of the proposed framework are (1) The ability to detect signals wirelessly within a Body Area Network (BAN) (2) Low-power and reliable data sensing through ZigBee network nodes and (3) Optimized analysis of data through an adaptive tiered architecture that maximizes the utility of processing and computational capacity at each of three stages. We are currently building a prototype of the proposed system using in-house ECG probes and ZigBee radio modules.
Factors in novice programmers' poor tracing skills
Authors: Vesa Vainio, Jorma Sajaniemi
Venue: ACM SIGCSE Bulletin (2007)

Novice programmers' program tracing skills have been found to be poor but the difficulties leading to inefficient tracing are not well known. To study this issue, we conducted exploratory interviews that included program comprehension tasks with novice students and analyzed comprehension protocols to identify specific difficulties affecting novices' ability to trace programs. Based on the qualitative analysis, we describe four specific difficulties students had with program tracing-single value tracing, confusing function and structure, inability to use external representations, and inability to raise abstraction level-and discuss ways to help students to overcome these difficulties.
A Robust Error Concealment Algorithm in Wireless Networks
Authors: Jianwei Niu, Congying Wei, Rui He, Jian Ma
Venue: Proceedings of the 21st International Conference on Advanced Information Networking and Applications Workshops - Volume 02 (2007)

Compressed video sequences are very vulnerable to channel disturbances when transmitted through the burst-packet-loss wireless channels. Transmission errors not only corrupt the current frame, but may also propagate to succeeding frames. We find that a number of current proposed post-processing error concealment methods exploit the spatial/temporal redundancy in the video stream can not actually conceal the transmission errors effectively, because they ignored the fact that the neighboring blocks can be easily lost by the burst packet losses and the correlation was considered only in the current frame, which all limited the ability to obtain an optimal recovery. In this paper, a novel error concealment algorithm is proposed for video transmissions in a wireless environment. Simulation proves that the proposed algorithm can be chosen as good trade-off between video quality and computational load in wireless networks.
Interactive presentation: Task scheduling under performance constraints for reducing the energy consumption of the GALS multi-processor SoC
Authors: Ryo Watanabe, Masaaki Kondo, Masashi Imai, Hiroshi Nakamura, Takashi Nanya
Venue: Proceedings of the conference on Design, automation and test in Europe (2007)

The present paper focuses on applications that are periodic and have both latency and throughput constraints. For these applications, pipeline scheduling is effective for reducing energy consumption. Thus, the present paper proposes a pipelined task scheduling method for minimizing the energy consumption of GALS MP-SoC under latency and throughput constraints. First, we model target GALS MP-SoC architecture and application tasks. We then show that the energy optimization problem under this model belongs to the class of Mixed-Integer Linear Programming. Next, we propose a new scheduling method based on simulated annealing for the purpose of solving this problem quickly. Finally, experimental results demonstrate that the proposed method achieves a significant energy reduction on a real application under a practical architecture.
On-chip communication architecture exploration: A quantitative evaluation of point-to-point, bus, and network-on-chip approaches
Authors: Hyung Gyu Lee, Naehyuck Chang, Umit Y. Ogras, Radu Marculescu
Venue: ACM Transactions on Design Automation of Electronic Systems (TODAES) (2007)

Traditionally, design-space exploration for systems-on-chip (SoCs) has focused on the computational aspects of the problem at hand. However, as the number of components on a single chip and their performance continue to increase, a shift from computation-based to communication-based design becomes mandatory. As a result, the communication architecture plays a major role in the area, performance, and energy consumption of the overall system. This article presents a comprehensive evaluation of three on-chip communication architectures targeting multimedia applications. Specifically, we compare and contrast the network-on-chip (NoC) with point-to-point (P2P) and bus-based communication architectures in terms of area, performance, and energy consumption. As the main contribution, we present complete P2P, bus-, and NoC-based implementations of a real multimedia application (i. e. the MPEG-2 encoder), and provide direct measurements using an FPGA prototype and actual video clips, rather than simulation and synthetic workloads. We also support the experimental findings through a theoretical analysis. Both experimental and analysis results show that the NoC architecture scales very well in terms of area, performance, energy, and design effort, while the P2P and bus-based architectures scale poorly on all accounts except for performance and area, respectively.
Incremental MLLR speaker adaptation by fuzzy logic control
Authors: Ing-Jr Ding
Venue: Pattern Recognition (2007)

This paper presents a fuzzy control mechanism for conventional maximum likelihood linear regression (MLLR) speaker adaptation, called FLC-MLLR, by which the effect of MLLR adaptation is regulated according to the availability of adaptation data in such a way that the advantage of MLLR adaptation could be fully exploited when the training data are sufficient, or the consequence of poor MLLR adaptation would be restrained otherwise. The robustness of MLLR adaptation against data scarcity is thus ensured. The proposed mechanism is conceptually simple and computationally inexpensive and effective; the experiments in recognition rate show that FLC-MLLR outperforms standard MLLR especially when encountering data insufficiency and performs better than MAPLR at much less computing cost.
Privilege messaging: an authorization framework over email infrastructure
Authors: Brent ByungHoon Kang, Gautam Singaraju, Sumeet Jain
Venue: Proceedings of the 20th conference on Large Installation System Administration (2006)

The current email infrastructure is burdened by multiple resource constraints and a plethora of security issues. Apart from the fact that email users are spending more time and effort sifting through unsolicited emails, more serious problems such as Phishing are on the rise. This can be attributed to a fundamental shortcoming in the current email infrastructure: a lack of an authorization framework. This allows any user to create content in anyone's mailbox. In this paper, we revisit the fundamental problem of nonexistent authorization and discuss the design of an effective authorization service overlaying the existing email infrastructure. We propose Privilege Messaging (P-Messaging), a fine-granular authorization framework that operates on the principle that a sender requires a set of privileges in order to send messages, simultaneously enables the receiver's infrastructure server to verify the messages before accepting it. We present a prototype implementation and discuss its benefits. An automatic classification of email can be effectively performed based on the privilege-tag. Privilege-tag can provide flexible and fine-granular reputation management than current domain-based solutions. The use of privilege-tag as entry ID in a white-list can be more manageable than the use of individual email address. Finally, the privilege-tag can be used as an email header, retaining the benefits of currently deployed MTA architecture, namely reliability and flexibility.
Extrinsic Recalibration in Camera Networks
Authors: Chris, Maarten Dumont, Philippe Bekaert
Venue: Proceedings of the Fourth Canadian Conference on Computer and Robot Vision (2007)

This work addresses the practical problem of keeping a camera network calibrated during a recording session. When dealing with real-time applications, a robust calibration of the camera network needs to be assured, without the burden of a full system recalibration at every (un)intended camera displacement. In this paper we present an efficient algorithm to detect when the extrinsic parameters of a camera are no longer valid, and reintegrate the displaced camera into the previously calibrated camera network. When the intrinsic parameters of the cameras are known, the algorithm can also be used to build ad-hoc distributed camera networks, starting from three calibrated cameras. Recalibration is done using pairs of essential matrices, based on image point correspondences. Unlike other approaches, we do not explicitly compute any 3D structure for our calibration purposes.
Design and implementation of HDTV encoder system with parallel processing architecture
Authors: Hongkai Xiong, Songyu Yu, Wei Ye
Venue: Proceedings of the The 8th International Conference on Communication Systems - Volume 02 (2002)

This paper presents a design procedure for an HDTV encoder with parallel processing architecture, which could get out the dilemma lying in high-speed digital processing circuitry and real-time compression. In the proposed system, an original HDTV picture is split to multiple sub-pictures of MPEG-2 MP@ML level, and then multiple sub-picture encoding modules (SEM) perform, respectively and simultaneously, MPEG-2 coding in the light of a joint rate control scheme. A normative HDTV PES stream of MPEG-2 MP@HL is built up by compositing multiple ES streams with different bit-rate. The paper hits the high points and supply appropriate implementation strategy during the propose design framework.
Towards a Requirements-driven Workbench for Supporting Software Certification and Accreditation
Authors: Seok-Won Lee, Robin A. Gandhi, Siddharth Wagle
Venue: Proceedings of the 29th International Conference on Software Engineering Workshops (2007)

Security certification activities for software systems rely heavily on requirements mandated by regulatory documents and their compliance evidences to support accreditation decisions. Therefore, the design of a workbench to support these activities should be grounded in a thorough understanding of the characteristics of certification requirements and their relationships with certification activities. To this end, we utilize our findings from the case study of a certification process of The United States Department of Defense (DoD) to identify the design objectives of a requirements-driven workbench for supporting certification analysts. The primary contributions of this paper are: identifying key areas of automation and tool support for requirements-driven certification activities; an ontology-driven dynamic and flexible workbench architecture to address process variability; and a prototype implementation.
A longitudinal study of intellectual development of engineering students: what really counts in our curriculum?
Authors: B. Palmer
Venue: Proceedings of the 30th Annual Frontiers in Education - Volume 02 (2000)

In the early 1990's several national reports called for reform in engineering education and suggested that the current preparation of engineering students fell short of the skills and competencies that would be required of practising engineers. Many engineering colleges across the country sought to address these problems with curricular reforms that incorporated more hands-on design work into the engineering curricula. The task of assessing the effectiveness of these design-infused curricula presents a critical challenge for engineering educators. At Penn State, we developed a longitudinal assessment program to evaluate the qualitative changes in students' thinking as they progressed through the engineering curriculum. This paper presents a summary of the results of the first longitudinal component of this assessment.
Multivariate analysis of student performance in large engineering economy classes
Authors: W. G. Sullivan
Venue: Proceedings of the 26th Annual Frontiers in Education - Volume 01 (1996)

Based on multivariate data collected over three years, linear regression equations are developed and used to assess student learning in large sections of engineering economy taught at Virginia Tech. In each year (1993, 1994 and 1995), more than 350 students in the fall semester voluntarily participated in this research. This paper presents the principal findings of the study and demonstrates the use of multivariate linear regression for evaluating student performance (learning) in engineering economy.
Mace: language support for building distributed systems
Authors: Charles Edwin Killian, James W. Anderson, Ryan Braud, Ranjit Jhala, Amin M. Vahdat
Venue: Proceedings of the 2007 ACM SIGPLAN conference on Programming language design and implementation (2007)

Building distributed systems is particularly difficult because of the asynchronous, heterogeneous, and failure-prone environment where these systemsmust run. Tools for building distributed systems must strike a compromise between reducing programmer effort and increasing system efficiency. We present Mace, a C++ language extension and source-to-source compiler that translates a concise but expressive distributed system specification into a C++ implementation. Mace overcomes the limitations of low-level languages by providing a unified framework for networking and event handling, and the limitations of high-level languages by allowing programmers to write program components in a controlled and structured manner in C++. By imposing structure and restrictions on how applications can be written, Mace supports debugging at a higher level, including support for efficient model checking and causal-path debugging. Because Mace programs compile to C++, programmers can use existing C++ tools, including optimizers, profilers, and debuggers to analyze their systems.
Voronoi diagram in optimal path planning
Authors: Priyadarshi Bhattacharya, Marina L. Gavrilova
Venue: Proceedings of the 4th International Symposium on Voronoi Diagrams in Science and Engineering (2007)

In this paper, we provide an algorithm based on Voronoi diagram to compute an optimal path between source and destination in the presence of simple disjoint polygonal obstacles. We evaluate the quality of the path based on clearance from obstacles, overall length and smoothness. We provide a detailed description of the algorithm for Voronoi diagram maintenance and dynamic updates. Experimental results demonstrate superior performance of the method in relation to other path planning algorithms.
A proof on the minimum and permissible sampling rates for the first-order sampling of bandpass signals
Authors: Y. Wu
Venue: Digital Signal Processing (2007)

In this paper, we present a rigorous mathematical proof on the minimum sampling rate as well as all acceptable sampling rates (independent of band position) for the first-order sampling of bandpass signals. It is shown that the minimum sampling rate is between 2@s (Nyquist rate) and 3@s, where @s is the bandwidth of a bandpass signal. It is also noted that the Nyquist rate is actually an asymptotic sampling rate for the first-order sampling of bandpass signals. A so-called csinc interpolator is used in the reconstruction of a bandpass signal from its samples, which makes the sampling theorem for bandpass signals congruent with the sampling theorem for lowpass signals.
Internet Security: Intrusion Detection and Prevention in Mobile Systems
Authors: Joseph G. Tront, Randy C. Marchany
Venue: Proceedings of the 40th Annual Hawaii International Conference on System Sciences (2007)

Daily commerce on the Internet consists of billions of dollars worth of transactions many of which occur between mobile and portable devices such as internet phones, PDAs, notebook computers and other similar devices. Unfortunately, the wireless Internet has become the lurking grounds for electronic n'er-do-wells who are constantly jeopardizing the processes of business.
Dynamic Speed and Sensor Rate Adjustment for Mobile Robotic Systems
Authors: Ala' Qadi, Steve Goddard, Jiangyang Huang, Shane Farritor
Venue: Proceedings of the 19th Euromicro Conference on Real-Time Systems (2007)

Mobile robotic systems must sense constraints imposed by a dynamically changing environment and predictably react to those changes in real-time. Complexity arises in mobile robotic systems because the computing platform travels through the environment with which the system is interacting. These systems have spatio-temporal requirements in the sense that correct behavior is defined in terms of both space and time. The focus of this paper is mobile robotic platforms that must sense their environment and avoid obstacles as they navigate from one point to another. We present a design and analysis methodology for these platforms that integrates spatio-temporal attributes with fixed priority realtime scheduling through the use of zone and processing window abstractions. We propose an algorithm for adjustment of the processing window in order maximize the speed of the robot as it faces obstacles in the environment.