ppxscal/embedding_network huggingface dataset:
Variant parametric types: A flexible subtyping scheme for generics
Authors: Atsushi Igarashi, Mirko Viroli
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (2006)

We develop the mechanism of variant parametric types as a means to enhance synergy between parametric and inclusion polymorphism in object-oriented programming languages. Variant parametric types are used to control both the subtyping between different instantiations of one generic class and the accessibility of their fields and methods. On one hand, one parametric class can be used to derive covariant types, contravariant types, and bivariant types (generally called variant parametric types) by attaching a variance annotation to a type argument. On the other hand, the type system prohibits certain method/field accesses, according to variance annotations, when these accesses may otherwise make the program unsafe. By exploiting variant parametric types, a programmer can write generic code abstractions that work on a wide range of parametric types in a safe manner. For instance, a method that only reads the elements of a container of numbers can be easily modified so as to accept containers of integers, floating-point numbers, or any subtype of the number type.Technical subtleties in typing for the proposed mechanism are addressed in terms of an intuitive correspondence between variant parametric and bounded existential types. Then, for a rigorous argument of correctness of the proposed typing rules, we extend Featherweight GJ---an existing formal core calculus for Java with generics---with variant parametric types and prove type soundness.
A New Hybrid Data Structure for 3D GIS
Authors: Wu Huixin, Xue Huifeng
Venue: Proceedings of the First International Conference on Innovative Computing, Information and Control - Volume 1 (2006)

In order to represent 3D GIS spatial entity effectively, a hybrid data structure model called BOT model (block octree tetrahedron model) is presented on the basis of geological block model, which combines octree and tetrahedral network (TEN) structures. With BOT generation algorithm, the block model is redivided with octree as general shape description and TEN as partial precise description, in which different gradations of grey are used to stand for different attributes of unit blocks. To reduce the memory space, a linear BOT coding technology is proposed as well. Finally, a 3D simulation system was developed to evaluate the performance of the approach proposed. The results of simulation experiments made with empirical data demonstrate that the BOT model holds merits of both octree and TEN and can represent 3D objects more effectively and precisely.
Application Specific Instruction Set Processor for Adaptive Video Motion Estimation
Authors: S. Momcilovic, T. Dias, N. Roma, L. Sousa
Venue: Proceedings of the 9th EUROMICRO Conference on Digital System Design (2006)

Motion estimation is the most demanding operation of a video encoder, corresponding to at least 80% of the overall computational cost. With the proliferation of portable handheld devices that support digital video coding, dataadaptive motion estimation algorithms have been required to dynamically configure the search pattern not only to avoid unnecessary computations and memory accesses but also to save energy. This paper proposes an Application Specific Instruction Set Processor (ASIP) to implement data-adaptive motion estimation algorithms, that is characterized by a specialized data-path and minimum and optimized instruction set. Due to its low-power nature, this architecture is specially adequate to develop motion estimators for portable, mobile and battery supplied devices. A cycle-based accurate simulator was also developed for the proposed ASIP and fast and data-adaptive search algorithms have been implemented, namely, the four-step search and the motion vector field adaptive search algorithms. Based on the proposed ASIP and the considered adaptive algorithms, several motion estimators were synthesized in 0.13ìm CMOS technology. Experimental results show that very-low power adaptive motion estimators have been achieved to encode QCIF video sequences.
Low power methodologies in energy managed computer systems
Authors: Massoud Pedram
Venue:  (2005)

One of the key challenges of computer system design is the management and conservation of energy. This challenge is evident in a number of ways. The goal may be to extend the battery lifetime in a portable, wireless device. The processing power, memory, and network bandwidth of such devices are rapidly increasing, resulting in an increase in demand for higher power dissipation, while the battery capacity is improving at a slow pace. Other goals may be to limit the cooling requirements of a computer system or to reduce the financial cost of operating a large computing facility. In this thesis, we focus on techniques to extend the battery lifetime in battery-powered electronic systems. Ideally, the problem of managing the energy consumed by computing devices should be addressed at all levels of system design---from low power circuits to applications capable of adapting to the available energy source. Many research and industrial efforts are currently focusing on developing low-power hardware as well as energy-aware application software in the design of energy-efficient computing systems. The objective in this research is to explore what can be done within systems resource management functions/policies to improve energy usage without requiring any specialized, low-power hardware and any explicit assistance from application software and compilers. This thesis focuses on developing methodologies and techniques for OS-directed energy management of the display subsystem in a high-performance, state-of-the-art computer system. By tackling this problems, we can provide effective OS-directed mechanisms, with corresponding software support, for reducing the overall power consumption of portable systems through a significant reduction in power dissipation of the display subsystem. Notice that this problem is an important example of changing the quality of objects displayed so as to improve the energy efficiency of the display subsystem at an undetectable or possibly acceptable level of image fidelity degradation. Advantages of our proposed techniques are that they require no hardware changes (or at maximum, they require self-contained minor changes, such as adding a DC-DC converter module), need no application software or compiler cooperation (although this information can be helpful, if it is provided), are employed at the runtime with the OS supervision and direct involvement (so that any timing-critical task can be executed within the required deadline), and finally, are highly flexible and scalable. In part two, energy management problem is studied in network of interacting systems. Wireless sensors are adopted as an example of energy manageable systems and as an application scenario the key problem of preventing disruptions or attacks on the flow of commodities and services in a large supply network, i.e., Network Safeguarding problem, is considered. The goal is to maximize the Monitoring Lifetime (MoL) of the sensor network subject to minimum levels of performance and Quality of Service (QoS) in the supply network. (Abstract shortened by UMI.)
The Impact of Agility on a Bachelor's Degree in Computer Science
Authors: Carol Wellington, Thomas Briggs, C. Dudley Girard
Venue: Proceedings of the conference on AGILE 2006 (2006)

Shippensburg University offers a Computer Science degree with the choice of five concentrations including Software Engineering. We first introduced agility as an XP component in part of our two-semester product development sequence. Within the software engineering concentration, agile concepts spread into our course on Software Metrics and Process Management. With that experience, our faculty have become interested in including agile concepts into other courses. This paper describes how a number of our undergraduate courses, the content of our computer science core, and our department's general health have been affected by agile techniques and philosophies.
A Modal Interpretation of the Logic of Interrogation
Authors: Rani Nelken, Chung-Chieh Shan
Venue: Journal of Logic, Language and Information (2006)

We propose a novel interpretation of natural-language questions using a modal predicate logic of knowledge. Our approach brings standard model-theoretic and proof-theoretic techniques from modal logic to bear on questions. Using the former, we show that our interpretation preserves Groenendijk and Stokhof's answerhood relation, yet allows an extensional interpretation. Using the latter, we get a sound and complete proof procedure for the logic for free. Our approach is more expressive; for example, it easily treats complex questions with operators that scope over questions. We suggest a semantic criterion that restricts what natural-language questions can express. We integrate and generalize much previous work on the semantics of questions, including Beck and Sharvit's families of subquestions, non-exhaustive questions, and multi-party conversations.
Resource-Driven Collaborative Component Deployment in Mobile Environments
Authors: Peter Rigole, Yolande Berbers
Venue: Proceedings of the International Conference on Autonomic and Autonomous Systems (2006)

Two techniques are presented in this paper that address the issue of hosting applications in a ubiquitous computing space: (1) context-aware component deployment and (2) self-adaptive component deployment configurations. The former focusses on deploying an application, which is composed of fine-grained components, in a mobile distributed computing environment based on resource information that is spread through context-data. The latter focusses on letting the component deployment configuration adapt itself when the resources in the environment change due to device mobility. Both techniques are solved using a single mechanism that is based on an extended version of collaborative reinforcement learning (CRL) in the design of our component deployment framework. In order to find local optimal solutions for deploying a component-based application in a distributed resource constrained environment, the CRL method balances the resource consumption of components on several nodes that are in each other's proximity.
3D Target Scale Estimation and Motion Segmentation for Size Preserving Tracking in PTZ Video
Authors: Yi Yao, Besma Abidi, Mongi Abidi
Venue: Proceedings of the 2006 Conference on Computer Vision and Pattern Recognition Workshop (2006)

In size preserving video tracking, the camera's focal length (zoom) is adjusted automatically to compensate for the changes in the target's image size caused by the relative motion between the camera and the target. The accurate estimation of these changes is paramount to the system performance. The existing method of choice for real-time target scale estimation applies structure from motion (SFM) based on the weak perspective projection model [1]. We design a target scale estimation algorithm with linear solution based on the more advanced paraperspective projection model. Another key problem in SFM based algorithms is the separation between foreground and background features (image corners), especially when composite camera and target motions are involved. This paper also addresses a fast foreground/background separation algorithm, the affine shape method. The resulting segmentation automatically adapts to the target's 3D geometry and motion. Experimental results illustrate the effectiveness of the proposed scale estimation and segmentation algorithms in tracking translating and rotating objects with a PTZ camera while preserving their sizes.
Implementation and Optimization of H.264/AVC Encoder on Blackfin (ADSP-BF537) Processor
Authors: Shi-lei Yan, Jian-wei Sun
Venue: Proceedings of the International Conference on Computational Inteligence for Modelling Control and Automation and International Conference on Intelligent Agents Web Technologies and International Commerce (2006)

Real-time video images communication needs efficient implementation and optimization about the video compression algorithms on power-efficient platforms. To meet such needs several compression methodologies and techniques have been proposed and standardized. This paper presents the implementation details of H.264/AVC (the latest standard for video compression) encoder on ADSP-BF537 processor based Analog Devices BF537-STAMP board, and gives several optimization techniques which have been concurrently employed in this work to improve the performance of the encoder. In this paper, the improvement in performance has been evaluated for each optimization step and the results of the optimization demonstrate the potential of the lowpower Micro-Signal Architecture of Blackfin processor as a good choice for next generation embedded multimedia applications.
Theta Responses Are Involved in Lexical&ndash;Semantic Retrieval during Language Processing
Authors: Marcel C.M. Bastiaansen, Marieke Van Der Linden, Mariken Ter Keurs, Ton Dijkstra, Peter Hagoort
Venue: Journal of Cognitive Neuroscience (2005)

Oscillatory neuronal dynamics, observed in the human electroencephalogram (EEG) during language processing, have been related to the dynamic formation of functionally coherent networks that serve the role of integrating the different sources of information needed for understanding the linguistic input. To further explore the functional role of oscillatory synchrony during language processing, we quantified event-related EEG power changes induced by the presentation of open-class (OC) words and closed-class (CC) words in a wide range of frequencies (from 1 to 30 Hz), while subjects read a short story. Word presentation induced three oscillatory components: a theta power increase (4&ndash;7 Hz), an alpha power decrease (10&ndash;12 Hz), and a beta power decrease (16&ndash;21 Hz). Whereas the alpha and beta responses showed mainly quantitative differences between the two word classes, the theta responses showed qualitative differences between OC words and CC words: A theta power increase was found over left temporal areas for OC words, but not for CC words. The left temporal theta increase may index the activation of a network involved in retrieving the lexical&ndash;semantic properties of the OC items.
Distributed, self-organizing replica placement in large scale networks
Authors: Dan Rubenstein
Venue:  (2006)

Emerging large scale distributed networking systems, such as P2P file sharing systems, sensor networks, and ad hoc wireless networks, require replication of content, functionality, or configuration to enact or optimize communication tasks. The placement of these replicated resources can significantly impact performance. In this thesis, we present self-organizing, fully distributed, asynchronous, scalable algorithms and protocols that can be used to place replicated resources in desirable locations in three different environments. We first explore theoretical properties of replica placement problems at a fundamental level, and develop a fully distributed protocol in the context of a graph with colored nodes, where a node's color indicates the replica/task that it is assigned. In this theoretical work, we introduce a novel mechanism with which each node in the network decides its own color, resulting in a graph coloring such that each node is close to any arbitrary replicated color. The combination of theoretical results and simulation show that the protocol stabilizes quickly to a coloring that is close to the optimal under a set of optimization criteria. We then study the distributed server placement problem in large-scale client-server networks, such as content distribution networks (CDN) and online gaming networks, as a real-world application of our replica placement algorithm. The problem is explored in the context of a server coloring problem, where each server node is assigned a color that represents a particular server resource. Simulation results show that the distributed algorithm quickly generates a placement for multiple colors simultaneously, and reduces the expected client-server distance by almost half compared to the distance when the assignment of replicated servers is done at random. Last, we design, implement, and evaluate a distributed channel assignment algorithm in multi-hop 802.11 mesh networks, taking a further step toward validating the effectiveness of our replica placement mechanism. While we take the same strategy in addressing the distributed assignment problem in a self-organizing manner, we also make a significant number of new contributions that deal with the unique challenges present in the wireless networking environment, from algorithmic modifications to resolving implementation-specific issues. Experimental results obtained from the testbed show that our channel assignment algorithm improves the network's capacity by 50% in comparison to a homogeneous channel assignment and by 20% in comparison to a random assignment.
The impact of individual learner characteristics and synchronous computer-mediated communication on language production in learners of english
Authors: Robert Ariew
Venue:  (2006)

As computer technology advances rapidly in the past decades, incorporating computer technology into classroom teaching has been popular, especially in the area of foreign language education because of its potential benefits. Among computer technology, computer mediated communication (henceforth, CMC) is widely used in language classrooms for its benefits, for example, more equal participation, a less stressful learning environment, and increased output (Chun, 1998; Kern, 1995; Warschauer, 1996). In addition, due to the hybrid nature of CMC, learners are allowed to have more time to process input, monitor and edit output (Kelm, 1992; Warschauer, 1996) resulting in more accurate and complex language production compared to face-to-face conversation. (Beauvois, 1992, 1995; Kern, 1995; Pellettieri, 2000; Sotillo, 2000; Warschauer, 1995, 1996). Several studies examined another benefits of CMC - the development of oral proficiency (Abrams, 2003; Beauvois, 1998b; Payne Whitney, 2002; Kost, 2004); however, the results of these studies are consistent, suggesting that oral proficiency may be enhanced by synchronous online discussion. Instead of investigating whether synchronous CMC is beneficial for all students, the present study aims to investigate the extent to which the factors such as personality types, amount of participation and previous experience using chat contribute most to the development of oral skills. That is, the present study focuses on individual, affective variables that could affect the effects of CMC on spoken language development among beginning learners of English. Employing a pre and post one-group comparison design, 16 students participated in the study and their oral skills were measure by two interviews and the interviews were scored by a native speaker informant and the researcher based on the scoring rubric that was adopted from the previous study (Payne Whitney, 2002). The results of repeated measures ANOVA revealed none of factors identified in the study were statistically significant. The results, however, should be interpreted that the use of CMC in language classroom does not disservice any group of students with a specific personality type or previous experience using chat. With numerous benefits known, chatting remains a valuable pedagogical tool to promote second language learning.
Integration of XML schemas at various "severity" levels
Authors: Pasquale De Meo, Giovanni Quattrone, Giorgio Terracina, Domenico Ursino
Venue: Information Systems (2006)

This paper presents a novel approach for the integration of a set of eXtensible Markup Language (XML) Schemas. The proposed approach is specialized for XML, almost automatic, semantic and "light". Further, an original peculiarity is that it is parametric w.r.t, a "severity" level against which the integration task is performed. The paper describes the approach in all details, illustrates various theoretical results, presents the experiments we have performed for testing it and, finally, compares it with various related approaches already proposed in the literature.
A Cross Media Platform for Personalized Leisure & Entertainment: The POLYMNIA Approach
Authors: Vasilios Anagnostopoulos, Sotiris Chatzis, Constantinos Lalos, Anastasios Doulamis, Dimitrios Kosmopoulos, Theodora Varvarigou, Helmut Neuschmied, Georg Thallinger, Stuart E. Middleton, Matthew Addis, Eduardo Bustos, Fabrizio Giorgini
Venue: Proceedings of the Second International Conference on Automated Production of Cross Media Content for Multi-Channel Distribution (2006)

The POLYMNIA project aims to develop an intelligent cross-media platform for personalised leisure and entertainment in thematic parks or venues. The system allows the visitors to be the real protagonist in the venue. Towards this goal, POLYMNIA platform is equipped with innovative imaging technologies for real time detection, localisation and tracking of ì human contentî , i.e., the human visitor within the recoding being made in real-time by the system. No constraints are imposed on the variation of the environment. New, content-based media representation and organisation schemes will be developed to provide scalable, efficient and user-oriented description of the ì human contentî , enabling efficient retrieval, access, and delivery across heterogeneous media platforms. In addition, adaptive mechanisms are employed to update the system response to the current usersí information needs and preferences.
Detection of nonstationary random signals in colored noise
Authors: W. T. Padgett, D. B. Williams
Venue: Proceedings of the Acoustics, Speech, and Signal Processing,1994. on IEEE International Conference - Volume 04 (1994)

This paper describes a novel method for detecting nonstationary signals in colored noise. A first order complex autoregressive, or AR(1), signal model is used which restricts the application of the detector to low order signals, i.e., those which are well modeled by a low order AR process and have only a single spectral peak. The detector assumes the noise covariance is stationary and known. The likelihood function is estimated in the frequency domain because the model simplifies, and the nonstationary frequency estimate can be obtained by an algorithm which approximates the Viterbi algorithm. The AR model parameters are then used to form the appropriate covariance matrix and the approximate likelihood is calculated. Therefore, the detector uses efficient approximations to approximate the generalized likelihood ratio test (GLRT). Simulation results are shown to compare the detector with the known signal likelihood ratio test.