ppxscal/embedding_network huggingface dataset:
A measurement study of vehicular internet access using in situ Wi-Fi networks
Authors: Vladimir Bychkovsky, Bret Hull, Allen Miu, Hari Balakrishnan, Samuel Madden
Venue: Proceedings of the 12th annual international conference on Mobile computing and networking (2006)

The impressive penetration of 802.11-based wireless networks in many metropolitan areas around the world offers, for the first time, the opportunity of a "grassroots" wireless Internet service provided by users who "open up" their 802.11 (Wi-Fi) access points in a controlled manner to mobile clients. While there are many business, legal, and policy issues to be ironed out for this vision to become reality, we are concerned in this paper with an important technical question surrounding such a system: can such an unplanned network service provide reasonable performance to network clients moving in cars at vehicular speeds.To answer this question, we present the results of a measurement study carried out over 290 "drive hours" over a few cars under typical driving conditions, in and around the Boston metropolitan area (some of our data also comes from a car in Seattle). With a simple caching optimization to speed-up IP address acquisition, we find that for our driving patterns the median duration of link-layer connectivity at vehicular speeds is 13 seconds, the median connection upload bandwidth is 30 KBytes/s, and that the mean duration between successful associations to APs is 75 seconds. We also find that connections are equally probable across a range of urban speeds (up to 60 km/hour in our measurements). Our end-to-end TCP upload experiments had a median throughput of about 30 KBytes/s, which is consistent with typical uplink speeds of home broadband links in the US. The median TCP connection is capable of uploading about 216 KBytes of data.Our high-level conclusion is that grassroots Wi-Fi networks are viable for a variety of applications, particularly ones that can tolerate intermittent connectivity. We discuss how our measurement results can improve transport protocols in such networks.
An operating system for a small computer
Authors: H. K. Hodge
Venue: ACM SIGSMALL Newsletter (1981)

Let me begin by defining what I consider to be a SMALL computer, in order to filter out any uninterested readers: an 8-bit CPU, 65K of address space, a dual floppy disk drive, printer and CRT. Why, with the cost of hardware (although not necessarily peripherals) continuing to decline, concern oneself with such an archaic setup? Three reasons (at least): it is what we at K-R have available; neither our budget nor our applications justify anything larger (at present); and it is fun. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Wireless Broadband Internet Access in Korea
Authors: Yoon Ju Lee, Sung Cheol Chang, Young Il Kim, Song In Choi, Jee Hwan Ahn
Venue: Proceedings of the International Conference on Systems and Networks Communication (2006)

This paper discusses the new technology of the Wireless Broadband (WiBro) Internet Access System based on IEEE 802.16d and 802.16e. It has the advantages of a seamless service by mobility of mobile cellular, and high-speed data transmission and low cost of WLAN. The WiBro system is designed to provide broadband Internet access to the mobile users by a seamless service. WiBro services could be a solution that satisfies customers' need on new mobile data services overcoming existing restrictions. The standardization and technology development for WiBro
Building a Relational Robot to be Student's Private Learning Secretary
Authors: Len-Yan Sun, Chih-Wei Chang, Gwo-Dong Chen, Jorng-Tzong Horng
Venue: Proceedings of the Sixth IEEE International Conference on Advanced Learning Technologies (2006)

Relational robot is an intelligent conversational agent designed to be a learning secretary for student to notify student of using our learning website on time. In this paper we will discuss some modules of relational robot to let it play a learning secretary role; it contains interaction module (verbal communication unit, nonverbal communication unit and process unit), internet interface, and communication interface with structure dialogue.
The Neurophysiology of Response Competition: Motor Cortex Activation and Inhibition following Subliminal Response Priming
Authors: Peter Praamstra, Ellen Seiss
Venue: Journal of Cognitive Neuroscience (2005)

Some widely used tasks in cognitive neuroscience depend on the induction of a response conflict between choice alternatives, involving partial activation of the incorrect response before the correct response is emitted. Although such ''conflict tasks'' are often used to investigate frontal-lobe-based conflict-monitoring processes, it is not known how response competition evolves in the motor cortex. To investigate the dynamics of motor cortex activation during response competition, we used a subliminal priming task that induced response competition while bypassing preresponse stage processing conflict. Analyses of movement-related EEG potentials supported an interaction between competing responses characterized by reciprocal inhibition. Inhibitory interactions between response channels contribute to the resolution of response conflict. However, the reciprocal inhibition at motor cortex level seemed to operate independent of higher level conflict-monitoring processes, which were relatively insensitive to response conflict induced by subliminal priming. These results elucidate how response conflict causes interference as well as the conditions under which frontal-lobe-based interference control processes are engaged.
How Do Movie Viewers Perceive Scene Structure from Dynamic Cues
Authors: Loong-Fah Cheong, Xu Xiang
Venue: Proceedings of the 2006 IEEE Computer Society Conference on Computer Vision and Pattern Recognition - Volume 1 (2006)

Cinema viewed from a location other than a Canonical Viewing Point (CVP) presents distortions to the viewer in both its static and dynamic aspects. Past works have investigated mainly the static aspect of this problem and attempted to explain why viewers still seem to perceive the scene very well. The dynamic aspect of depth perception, which is known as structure from motion, and its possible distortion, have not been well investigated. In this paper, we derive the dynamic depth cues perceived by the viewer and use the so-called isodistortion framework to understand its distortion. The result is that viewers seated at a reasonably central position experience a shift in the intrinsic parameters of their visual systems. Despite this shift, the key properties of the perceived depths remain largely the same, being determined in the main by the accuracy to which extrinsic motion parameters can be recovered. For a viewer seated at a non-central position and watching the movie screen with a slant angle, the view is related to the view at the CVP by a homography, resulting in various aberrations such as non-central projection.
Effects of conceptual representation on learning from hypermedia
Authors: Lei Liu, Surabhi Marathe, Cindy E. Hmelo-Silver
Venue: Proceedings of the 7th international conference on Learning sciences (2006)

Studying complex systems is increasingly important in many domains. Several features shared by complex systems hinder deep understanding. For example, understanding complex systems involves thinking about multiple interdependent levels, non-linear causality and/or emergence. Conceptual representations offer opportunities to become integrating frameworks across different domains. This study investigates how alternative conceptual representations embodied in hypermedia can help middle school students better understand a complex system, the human respiratory system. We designed two versions of instructional hypermedia based on structure-behavior-function theory. SBF is a conceptual representation that is part of the disciplinary toolbox of biologists and thus is an appropriate representation for learning in this domain. One hypermedia was function-centered while the other was structure-centered. We contrasted the instructional effects of these two alternative conceptual representations. Students using the function-centered hypermedia developed deeper understanding than those using the structure-centered version on one of the two measures. Implications and limitations are discussed.
Towards Rules and Laws for Software Factories and Evolvability: A Case-Driven Approach
Authors: Herwig Mannaert, Jan Verelst, Kris Ven
Venue: Proceedings of the International Conference on Software Engineering Advances (2006)

The ever-growing size and complexity of software systems creates a strong need for a major improvement in productivity in the software development process. However, automated production does not yet have an equivalent in the software development industry. Maintenance costs in particular, due to changes in requirements, remain extremely high in most software systems. Structured component models, component-based development processes, and initiatives for software factories are trying to tackle these issues. This paper states that there is a need to establish firm rules and laws that govern the process of software changes and evolvability. In order to contribute to the process of discovering these rules and laws, a case-driven approach is used. Based on a highly structured and large-scale codebase, an attempt is made to identify and quantify impacts and propagations of basic changes. Though the study is limited to a single codebase, the purpose is to contribute to an inductive reasoning process that may one day establish laws for software evolvability, similar to the mathematical foundation of systems theory.
Generating mobile device user interfaces for diagram-based modelling tools
Authors: Dejin Zhao, John Grundy, John Hosking
Venue: Proceedings of the 7th Australasian User interface conference - Volume 50 (2006)

Mobile display devices such as phones and PDAs have become very widely available and used. However, most content on these devices is limited to text, static images and motion video. Displaying and interacting with dynamic diagrammatic content on such devices is difficult, as is engineering applications to implement such functionality. We describe a set of plug-in components for a meta-diagramming tool that enable a diagram type to be visualized and interacted with on mobile devices. Key features of our approach include generating diagram content from an existing meta-tool, run-time user configuration of diagram appearance and navigation, and multi-level, zoomable diagrams and diagram content. We describe our experiences prototyping, using and evaluating this new mobile device diagramming technology
Large-scale Satellite Image Browsing using Automatic Semantic Categorization
Authors: Ashish Parulekar, Ritendra Datta, Jia Li, James Z. Wang
Venue: Proceedings of the Tenth IEEE International Conference on Computer Vision Workshops (2005)

We approach the problem of large-scale satellite image browsing from a content-based retrieval and semantic categorization perspective. A two-stage method for query based automatic retrieval of satellite image patches is proposed. The semantic category of query patches are determined and patches from that category are ranked based on an image similarity measure. Semantic categorization is done by a learning approach involving the two-dimensional multi-resolution hidden Markov model (2-D MHMM). Patches that do not belong to any trained category are handled using a support vector machine (SVM) based classifier. Experiments yield promising results in modeling semantic categories within satellite images using 2-D MHMM, producing accurate and convenient browsing. We also show that prior semantic categorization improves retrieval performance.
Integration of Top-down and Bottom-up Information for Image Labeling
Authors: Takahiro Toyoda, Keisuke Tagami, Osamu Hasegawa
Venue: Proceedings of the 2006 IEEE Computer Society Conference on Computer Vision and Pattern Recognition - Volume 1 (2006)

This paper proposes a novel framework that integrates bottom-up information and top-down information for scene understanding. Bottom-up information is derived from local features of texture and color. Top-down information is generated from a holistic image context. The information is integrated effectively by extension of the Ising model, which is a simple model of ferromagnetism. Locally and globally consistent image recognition is achieved through an iterative process. The proposed method showed 91.8% accuracy in road-image labeling, which is superior to results obtained using only bottom-up information (81.9%) and the best accuracy obtained using the other method (90.7%).
Agent-Based Negotiation Techniques for a Grid: The Prophet Agents
Authors: Massimo Orazio Spata, Giuseppe Pappalardo, Salvatore Rinaudo, Tonio Biondi
Venue: Proceedings of the Second IEEE International Conference on e-Science and Grid Computing (2006)

The aims of this research are to introduce a new transparent control paradigm and to consolidate Grid resources by a statistical approach based on Agents and on Queuing Theory. These goals are obtained through the creation of a new category of Agents called "Prophet Agents" with an agent-based peer-to-peer framework named JADE, created using the Java programming language. The goal of Prophet Agents inside a Grid is to estimate workload and completion time of a given job class in a specific class of servers. Moreover, agents are used to automate the "matchmaking" process and to consolidate Grid resources by adding new computing servers if necessary.
Implementation of dispatching algorithms for elevator systems using reconfigurable architectures
Authors: Daniel M. Muñoz, Carlos H. Llanos, Mauricio Ayala-Rincón, Rudi van Els, Renato P. Almeida
Venue: Proceedings of the 19th annual symposium on Integrated circuits and systems design (2006)

Elevator Group Control Systems (EGCSs) manage multiple elevators in a building transporting efficiently passengers. The performance of an EGCS is measured by means of several metrics such as the average waiting time of passengers, the percentage of the passengers waiting more than some predetermined time, power consumption, among others. Four elevator dispatching algorithms are analyzed and implemented using reconfigurable architectures based on FPGAs. The system is based on Local Controller Systems (LCSs), one for each elevator, and a protocol based on an RS485 network for interconnecting the LCSs. The FPGAs implement the LCSs. A Java interface was implemented for testing and monitoring the system and the EGCS function. The novelty of this approach is that the LCSs are capable to run the different dispatching algorithms, which are suitable for different passenger traffic situations, while the EGCS only must determine the best algorithm to be run in each LCS. The data traffic in the network is reduced given that the EGCS is not directly involved in calculating next floors to be visited. The algorithms were described in VHDL and implemented on Spartan3 FPGA based boards.
Selecting and Composing Web Services through Iterative Reformulation of Functional Specifications
Authors: Jyotishman Pathak, Samik Basu, Robyn Lutz, Vasant Honavar
Venue: Proceedings of the 18th IEEE International Conference on Tools with Artificial Intelligence (2006)

We propose a specification-driven approach to Web service composition. The proposed framework allows users to start with a high-level, possibly incomplete specification of a desired (goal) service that is to be realized using a subset of the available component services. These services are represented by the system using transition systems augmented with guards over variables with infinite domains and are used to determine a strategy for their composition that would realize the goal service. In the event that the goal service cannot be realized using the available services, the system identifies the cause(s) for such failure which can then be used by the developer to reformulate the goal specification. Thus, the system supportsWeb service composition through iterative refinement of the functional specifications. We present a prototype implementation in tabled-logic programming environment that illustrates the key features of the proposed approach.
Delay analysis of packet scheduling with multi-users diversity in wireless CDMA systems
Authors: Sung Kyung Kim, Chung Gu Kang
Venue: Wireless Networks (2005)

There have been a number of studies that investigate efficient packet scheduling schemes to support quality of service of multiple real-time data users and to increase capacity of non-real-time users sharing a wireless channel. We consider the problem of scheduling transmissions of multiple data users sharing the same wireless channel so as to satisfy delay or throughput and present a general packet scheduling, called MBCS (Multi-users Best Channel Scheduling) which takes advantage of the multi-user diversity of a mobile wireless system. In this paper, a queuing model that represents radio resource management for supporting packet data services is developed for the purpose of evaluating the performance of wireless CDMA systems. Numerical results show that delay performance of the proposed scheduler is higher than that of the Single-user Best Channel Scheduler (SBCS) depending on the time-varying channel status.
Low voltage actuated RF micromechanical switches fabricated using CMOS-MEMS technique
Authors: Ching-Liang Dai, Jing-Han Chen
Venue: Microsystem Technologies (2006)

This study investigates the fabrication of radio frequency (RF) micromechanical switches with low actuation voltage using the commercial 0.35&#x00a0;&#x03bc;m double polysilicon four metal (DPFM) complementary metal oxide semiconductor (CMOS) process and the post-process. The advantages of RF micromechanical switches include low pull-down voltage and ease of post-processing. Three types of RF micromechanical switches are designed and manufactured. The RF switches are capacitive type, and the structures of the switches comprise coplanar waveguide (CPW) transmission lines, supported springs and a suspended membrane. The post-process requires only a wet etching silicon dioxide layer. Experimental results show that type-c switch needs only a pull-down voltage of 7&#x00a0;V.
CMOS image sensors for sensor networks
Authors: Eugenio Culurciello, Andreas G. Andreou
Venue: Analog Integrated Circuits and Signal Processing (2006)

We report on two generations of CMOS image sensors with digital output fabricated in a 0.6 ¿m CMOS process. The imagers embed an ALOHA MAC interface for unfettered self-timed pixel read-out targeted to energy-aware sensor network applications. Collision on the output is monitored using contention detector circuits. The image sensors present very high dynamic range and ultra-low power operation. This characteristics allow the sensor to operate in different lighting conditions and for years on the sensor network node power budget.
Java Annotated Concurrency Based on the Concurrent Package
Authors: Hong Zhu, Zhaolin Yin, Ying Ding
Venue: Proceedings of the Seventh International Conference on Parallel and Distributed Computing, Applications and Technologies (2006)

JAC is an extended Java that introduces a higher level of concurrency, hiding threads and separating thread synchronization from application logic in a declarative fashion. java.util.concurrent package provides some excellent and powerful concurrent components. This paper introduces how to reconstruct the JAC precompiler to improve the JAC using concurrent package. The new precompiler can create Java code based on the concurrent package.
Run-time reconfigurabilility and other future trends
Authors: J. Becker, M. Hübner
Venue: Proceedings of the 19th annual symposium on Integrated circuits and systems design (2006)

Research laboratories all over the world work in the field of embedded systems. Since dynamic and partial reconfiguration found its way from academic labs to industry research and development groups, investigation for system integration of real-world applications is a challenging task. Novel trends show, that the exploitation of dynamic and partial reconfiguration in embedded systems provide flexibility in different kind of applications. Reliability, failure-redundancy and run-time adaptivity by usage of real-time hardware reconfiguration are important keywords for actual and future embedded systems. What is the impact of this more and more established methodology for future embedded systems and where are additional challenges and benefits.
Helping the Teacher to Re-Organize Tasks in a Collaborative Learning Activity: An Agent-Based Approach
Authors: Thibault Carron, Jean-Charles Marty, Jean-Mathias Heraud, Laure France
Venue: Proceedings of the Sixth IEEE International Conference on Advanced Learning Technologies (2006)

Our work aims at providing teachers with an observation tool making the learning task flexible and more adaptive. The main point of this paper deals with an agent approach to support the observation task of the teacher during a learning session. A multi-agent system architecture is proposed and discussed.
Experimental Control of a Two-Dof Flexible Robot Manipulator by Optimal and Sliding Methods
Authors: A. Sanz, V. Etxebarria
Venue: Journal of Intelligent and Robotic Systems (2006)

This paper presents an experimental study of a robust control scheme for flexible-link robotic manipulators. The design is based on a simple strategy for trajectory tracking which exploits the two-time scale nature of the flexible part and the rigid part of the dynamic equations of this kind of robotic arms: A slow subsystem associated with the rigid motion dynamics and a fast subsystem associated with the flexible link dynamics. Two experimental approaches are considered. In a first test an LQR optimal design strategy is used, while a second design is based on a sliding-mode scheme. Experimental results on a laboratory two-dof flexible manipulator show that this composite approach achieves good closed-loop tracking properties for both design philosophies, which compare favorably with conventional rigid robot control schemes.
Estimates for n-widths of the Hardy-type operators (Addendum to "Improved estimates for the approximation numbers of the Hardy-type operators")
Authors: J. Lang
Venue: Journal of Approximation Theory (2006)

Consider the Hardy-type operator T: LP (a,b) → LP (a,b), -∞ ≤ a < b ≤ ∞, which is defined by (Tf)(x) = v(x) ∫ax u(t)f(t)dt. It is shown that ρn (T) = 1/n αP ∫ab u(x)v(x)+O(n-2), where ρn (T) stands for any of the following: the Kolmogorov n-width, the Gel'fand n-width, the Bernstein n-width or the nth approximation number of T.