ppxscal/embedding_network huggingface dataset:
Output-sensitive algorithms for optimally constructing the upper envelope of straight line segments in parallel
Authors: N. Gupta, S. Chopra
Venue: Journal of Parallel and Distributed Computing (2007)

The importance of the sensitivity of an algorithm to the output size of a problem is well-known especially if the upper bound on the output size is known to be not too large. In this paper we focus on the problem of designing very fast parallel algorithms for constructing the upper envelope of straight-line segments that achieve the O(nlogH) work-bound for input size n and output size H. When the output size is small, our algorithms run faster than the algorithms whose running times are sensitive only to the input size. Since the upper bound on the output size of the upper envelop problem is known to be small (n@a(n)), where @a(n) is a slowly growing inverse-Ackerman's function, the algorithms are no worse in cost than the previous algorithms in the worst case of the output size. Our algorithms are designed for the arbitrary CRCW PRAM model. We first describe an O(logn.(logH+loglogn)) time deterministic algorithm for the problem, that achieves O(nlogH) work bound for H=@W(logn). We then present a fast randomized algorithm that runs in expected time O(logH.loglogn) with high probability and does O(nlogH) work. For logH=@W(loglogn), we can achieve the running time of O(logH) while simultaneously keeping the work optimal. We also present a fast randomized algorithm that runs in O@?(logn/logk) time with nk processors, k>log^@W^(^1^)n. The algorithms do not assume any prior input distribution and the running times hold with high probability.
Multivariate Density-Based 3D Shape Descriptors
Authors: Ceyhun Burak Akgul, Bulent Sankur, Francis Schmitt, Yucel Yemez
Venue: Proceedings of the IEEE International Conference on Shape Modeling and Applications 2007 (2007)

We address the 3D object retrieval problem using multivariate density-based shape descriptors. Considering the fusion of first and second order local surface information, we construct multivariate features up to five dimensions and process them by the kernel density estimation methodology to obtain descriptor vectors. We can compute these descriptors very efficiently using the fast Gauss transform algorithm. We also make use of descriptor level information fusion by concatenating descriptor vectors to increase their discrimination power further. To render the resulting descriptors storage-wise efficient, we develop two analytical tools, marginalization and probability density suppression, for descriptor dimensionality reduction. The experiments on two different databases, Princeton Shape Benchmark and Sculpteur, show that, boosted with both feature level and descriptor level information fusion, and powered with fast computational schemes, the density-based shape description framework enables effective and efficient 3D object retrieval.
Wireless Sensor Network: Research vs. Reality Design and Deployment Issues
Authors: Mohamed Youssef, Naser El-Sheimy
Venue: Proceedings of the Fifth Annual Conference on Communication Networks and Services Research (2007)

The availability of low cost, low power, and miniature embedded processors, radios, and sensors, integrated on a single chip, is leading to the use of wireless communications and computing for interacting with the physical world in many civilian and military applications. The resulting systems, called Wireless Sensor Networks (WSN). The advances in the integration of complex wireless integrated products and the increase in performance and functionality of the design tools, the requirements and properties of a single device (sensor node) are well understood. Yet it is not simple and straightforward to implement WSN concepts into a functional prototype system or even a commercial product. This tutorial will address the key factors in WSN design. The capabilities of the current WSNs will be examined. The new security scenarios for WSN will be illustrated. Different localization techniques in WSN will be discussed and compared. Future trends in WSN research will be introduced.
Feature peeling
Authors: Muhammad Muddassir Malik, Torsten Möller, M. Eduard Gröller
Venue: Proceedings of Graphics Interface 2007 (2007)

We present a novel rendering algorithm that analyses the ray profiles along the line of sight. The profiles are subdivided according to encountered peaks and valleys at so called transition points. The sensitivity of these transition points is calibrated via two thresholds. The slope threshold is based on the magnitude of a peak following a valley, while the peeling threshold measures the depth of the transition point relative to the neighboring rays. This technique separates the dataset into a number of feature layers. The user can scroll through the layers inspecting various features from the current view position. While our technique has been inspired by opacity peeling approach, we demonstrate that we can reveal detectable features even in the third and forth layers for both CT and MRI datasets.
Experiences building PlanetLab
Authors: Larry Peterson, Andy Bavier, Marc E. Fiuczynski, Steve Muir
Venue: Proceedings of the 7th USENIX Symposium on Operating Systems Design and Implementation - Volume 7 (2006)

This paper reports our experiences building PlanetLab over the last four years. It identifies the requirements that shaped PlanetLab, explains the design decisions that resulted from resolving conflicts among these requirements, and reports our experience implementing and supporting the system. Due in large part to the nature of the "PlanetLab experiment," the discussion focuses on synthesis rather than new techniques, balancing system-wide considerations rather than improving performance along a single dimension, and learning from feedback from a live system rather than controlled experiments using synthetic workloads.
Firefly-inspired Heartbeat Synchronization in Overlay Networks
Authors: Ozalp Babaoglu, Toni Binci, Mark Jelasity, Alberto Montresor
Venue: Proceedings of the First International Conference on Self-Adaptive and Self-Organizing Systems (2007)

Heartbeat synchronization strives to have nodes in a distributed system generate periodic, local "heartbeat events approximately at the same time. Many useful distributed protocols rely on the existence of such heartbeats for driving their cycle-based execution. Yet, solving the problem in environments where nodes are unreliable and messages are subject to delays and failures is non-trivial. We present a heartbeat synchronization protocol for overlay networks inspired by mathematical models of flash synchronization in certain species of fireflies. In our protocol, nodes send flash messages to their neighbors when a local heartbeat triggers. They adjust the phase of their next heartbeat based on incoming flash messages using an algorithm inspired by mathematical models of firefly synchronization. We report simulation results of the protocol in various realistic failure scenarios typical in overlay networks and show that synchronization emerges even when messages can have significant delay subject to large jitter.
Portable multithreading: the signal stack trick for user-space thread creation
Authors: Ralf S. Engelschall
Venue: Proceedings of the annual conference on USENIX Annual Technical Conference (2000)

This paper describes a pragmatic but portable fallback approach for creating and dispatching between the machine contexts of multiple threads of execution on Unix systems that lack a dedicated user-space context switching facility. Such a fallback approach for implementing machine contexts is a vital part of a user-space multithreading environment, if it has to achieve maximum portability across a wide range of Unix flavors. The approach is entirely based on standard Unix system facilities and ANSI-C language features and especially does not require any assembly code or platform specific tricks at all. The most interesting issue is the technique of creating the machine context for threads, which this paper explains in detail. The described approach closely follows the algorithm as implemented by the author for the popular user-space multithreading library GNU Portable Threads (GNU Pth, [25]) which this way quickly gained the status of one of the most portable user-space multithreading libraries.
Fast Rendering for a Multifinger Haptic Display
Authors: Blake Hannaford, Rainer Leuschke
Venue: Proceedings of the Second Joint EuroHaptics Conference and Symposium on Haptic Interfaces for Virtual Environment and Teleoperator Systems (2007)

An algorithm is described for fast rendering of surfaces for haptic interaction with multiple fingers. The algorithm uses a human-defined geometrical map to quickly cache surface triangles for constant time solution of the collision detection problem. The map is a 1, 2, or 3 dimensional manifold onto which it is easy to project the haptic interaction point. Dividing it's surface into quantized bins allows easy reference to a small set of triangles which can be checked for collision. Although the algorithm relies on some one-time manual input (i.e. defining the contact map), it represents a significant increase in speed without a substantial memory penalty.
Towards Secure Mobile P2P Systems
Authors: James Walkerdine, Simon Lock
Venue: Proceedings of the Second International Conference on Internet and Web Applications and Services (2007)

The growth of mobile devices with near PC equivalent capabilities has brought with it the possibility of mobile P2P systems. However, the nature of mobile devices brings additional issues that need to be considered, especially for when considering system security. This paper presents our initial work on the EU funded PEPERS project that seeks to support the development of secure mobile P2P applications. A core part of this support is with the design and development of a mobile P2P security platform.
Performance Modeling and Prediction of Parallel and Distributed Computing Systems: A Survey of the State of the Art
Authors: Sabri Pllana, Ivona Brandic, Siegfried Benkner
Venue: Proceedings of the First International Conference on Complex, Intelligent and Software Intensive Systems (2007)

Performance is one of the key features of parallel and distributed computing systems. Therefore, in the past a significant research effort was invested in the development of approaches for performance modeling and prediction of parallel and distributed computing systems. In this paper we identify the trends, contributions, and drawbacks of the state of the art approaches. We describe a wide range of the performance modeling approaches that spans from the high-level mathematical modeling to the detailed instruction-level simulation. For each approach we describe how the program and machine are modeled and estimate the model development and evaluation effort, the efficiency, and the accuracy. Furthermore, we present an overall evaluation of the presented approaches.
Temperature-limited microprocessors: Measurements and design implications
Authors: Hendrik F. Hamann, Alan Weger, James Lacey, Zhigang Hu, Pradip Bose, Erwin Cohen, Jamil Wakil
Venue: Proceedings of the 20th International Conference on VLSI Design held jointly with 6th International Conference: Embedded Systems (2007)

The details of the power distribution of state of the art CMOS chips (e.g., local regions of high power (or hotspots), which disproportionally drive up junction temperatures) can have a severe impact on reliability, manufacturing yield and chip performances. In this paper we discuss the results of a recently developed technique (Spatially-resolved imaging of micro-processor power (SIMP)), which can measure power and temperature distributions of high power chips (e.g., microprocessors) under full operating conditions. Specifically, we present detailed microprocessor power distributions for different workloads with and without power/thermal management. The data yields a more comprehensive understanding of the relationships between hotspots and the respective designs, layouts, floorplans, micro-architectures and thermal/power management schemes, which is discussed in detail.
Efficient sampling and feature selection in whole sentence maximum entropy language models
Authors: S. F. Chen
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1999. on 1999 IEEE International Conference - Volume 01 (1999)

Conditional maximum entropy models have been successfully applied to estimating language model probabilities of the form P(w|h), but are often to demanding computationally. Furthermore, the conditional framework does not lend itself to expressing global sentential phenomena. We have previously introduced a non-conditional maximum entropy language model which directly models the probability of an entire sentence or utterance. The model treats each utterance as a "bag of features", where features are arbitrary computable properties of the sentence. Using the model is computationally straightforward since it does not require normalization. Training the model requires efficient sampling of sentences from an exponential distribution. In this paper, we further develop the model and demonstrate its feasibility and power. We compare the efficiency of several sampling techniques. implement smoothing to accommodate rare features, and suggest an efficient algorithm for improving the convergence rate. We then present a novel procedure for feature selection, which exploits discrepancies between the existing model and the training corpus. We demonstrate our ideas by constructing and analyzing competitive modes in the Switchboard domain.
Genetic programming with smooth operators for arithmetic expressions: diviplication and subdition
Authors: R. K. Ursem, T. Krink
Venue: Proceedings of the Evolutionary Computation on 2002. CEC '02. Proceedings of the 2002 Congress - Volume 02 (2002)

This paper introduces the smooth operators for arithmetic expressions as an approach to smoothening the search space in Genetic Programming (GP). Smooth operator GP interpolates between arithmetic operators such as * and /, thereby allowing a gradual adaptation to the problem. The suggested approach is compared to traditional GP on a system identification problem.
Eye-balls: juggling with the virtual
Authors: Joe Marshall, Steve Benford, Tony Pridmore
Venue: Proceedings of the 6th ACM SIGCHI conference on Creativity cognition (2007)

The authors will introduce and demonstrate a novel computer vision based system for augmented performance. Unlike previous systems, which have primarily focused on 'high art' forms such as modern dance, this system is designed for use during a juggling performance. The system allows a juggler to interact with a computer through their movements, and the movements of the balls, to create audio and visual projections which respond to their performance. This system has been designed in an iterative process involving amateur and professional performers, in order to create a system which is truly accessible. In particular, this project takes inspiration from mass market interactive entertainment and has been developed to only use commodity hardware and to be easily distributable, in order to allow it to be used within the small, self funded groups common in the circus arts community.
Channel-number-compressed multi-channel acoustic echo canceller for high-presence teleconferencing system with large display
Authors: A. Nakagawa
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 02 (2000)

Sound localization is important to make conversation easy between local and remote sites in a teleconference. This requires a multi-channel sound system having a multi-channel acoustic echo canceller (MAEC). The appropriate number of channels is determined from a trade-off between high presence and MAEC performance, so it is not possible to increase the channel number by much. We propose a channel-number-compressed MAEC to provide teleconferencing systems that exhibit high presence. The channel number of the MAEC inputs is compressed and that of its outputs is expanded.
Exploiting partial knowledge of satisfying assignments
Authors: Kazuo Iwama, Suguru Tamaki
Venue: Discrete Applied Mathematics (2007)

Recently Schoning has shown that a simple local-search algorithm for 3SAT achieves the currently best upper bound, i.e., an expected time of 1.334^n. In this paper, we show that this algorithm can be modified to run much faster if there is some kind of imbalance in satisfying assignments and we have a (partial) knowledge about that. Especially if a satisfying assignment has imbalanced 0's and 1's, i.e., p"1n 1's and (1-p"1)n 0's, then we can find a solution in time 1.260^n when p"1=13 and 1.072^n when p"1=0.1. Such an imbalance often exists in SAT instances reduced from other problems. As a concrete example, we investigate a reduction from 3DM and show our new approach is nontrivially faster than its direct algorithms. Preliminary experimental results are also given.
A study on behavioral structure of artificial market based on adaptive game
Authors: T. Hamada, H. Kawamura, M. Yamamoto, A. Ohuchi
Venue: Proceedings of the Evolutionary Computation on 2002. CEC '02. Proceedings of the 2002 Congress - Volume 02 (2002)

We analyze the behavior of players in the situation where they recognize an identical situation as a simple market-like place differently. In our model a player considers the others as a representative player. We examine the player's behavior when with and without fluidity of players.
A Comment on "Multibeam Antenna-Based Topology Control with Directional Power Intensity for Ad Hoc Networks"
Authors: Saralees Nadarajah
Venue: IEEE Transactions on Mobile Computing (2007)

An explicit analytical expression is derived for computing the expected number of symmetric neighbors considered by Huang and Shen [1]. The expression involves a well-known special function. The practical advantages of using the analytical expression are established.
Robust matching pursuits video transmission using the HIPERLAN/1 air interface standard
Authors: P. Czerepinski
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 04 (2000)

Matching pursuits over a basis of separable Gabor functions has been demonstrated to outperform DCT methods for low bit rate video coding. This paper introduces an error resilient implementation of the matching pursuits algorithm, based on the error resilient positional code. Coded video is transmitted using the simulated HIPERLAN/1 air interface standard, which recommends ARQ as a means of overcoming channel errors. This may be unsuitable for real time and broadcast applications. Therefore, a modified HIPERLAN/1 receiver is proposed in this paper, which does not use ARQ to retransmit erroneous packets but instead passes them to the video decoder to exploit error resilience. This strategy provides an acceptable reconstruction quality for average bit error rates equal to 1 in 1000 and is superior to a standard compliant system in the absence of ARQ. This confirms that wireless LAN standards should support a transparent mode for video applications.
Development of Multi-Object Tracking System Based on Omni-Directional Vision Sensor
Authors: Tang Yiping, Ye Yongjie, Jin Haimin
Venue: Proceedings of the 16th International Conference on Artificial Reality and Telexistence--Workshops (2006)

Omni-Directional Vision Sensor (ODVS) is one of important components of sensor networks. Design of ODVS, embedded Linux ODVS, video server of ODVS, and software development of ODVS applications are studied in this paper. In addition, the applications of multi-object automatic tracking systems based on ODVS are described in details. Moreover, experimental results are proposed. This research is significant for sensor networks to be efficiently and effectively implemented.
A Novel Routing Protocol Integrate Power Balance for Ad Hoc Networks
Authors: Shih Yang Lin, Jian Pan Li, Lin Yu Wu, Guang Ming Wu
Venue: Proceedings of the Third International Conference on Networking and Services (2007)

In the recent years, there are many researches proposed various way to increase the performance of the wireless network. In this paper, we found some drawbacks from the protocol ILAR. There are some nodes around the border of the broadcast coverage might move out soon easily, it leads routing path to broken. Another problem in the ILAR is it may have another better forwarding node can be chose. On the other hand, a relay node could fail due to it usually relays data packets. Therefore we proposed a novel routing protocol integrate power balance scheme (NRMPB) to improve the problems above. Furthermore, the NRMPB employs the position information and addition the power saving scheme to balance the energy of each nodes and longer whole networks live. The simulation results our scheme has better performance than other scheme.
Shaping the Post-merger Information Systems Integration Strategy
Authors: Maria Alaranta, Stefan Henningsson
Venue: Proceedings of the 40th Annual Hawaii International Conference on System Sciences (2007)

Many researchers and business professionals have emphasized the importance and difficulties of successful information systems (IS) integration in the context of mergers and acquisitions (M&A). However, existing research remains sparse, failing to explain how firms design their IS integration strategy and its relation to successful IS integration. In order to overcome this shortcoming, we adapt six dimensions of strategic IS planning to the post-merger integration situation, namely comprehensiveness, formalization, focus, flow, participation, and consistency in the post-merger IS integration context. We then use two indepth cases studies to shed light on these constructs. We find evidence that contradicts the typical view presented in the M&A literature, and argue that there are several different approaches to post-merger IS integration planning. In the analysis, we point out specific differences between the cases that eventually lead up to these fundamentally different approaches to IS integration design.
Experiences in measuring the reliability of a cache-based storage system
Authors: Dan Lambright
Venue: Proceedings of the 1st conference on Industrial Experiences with Systems Software - Volume 1 (2000)

We present our experiences in benchmarking the reliability of the cache component of a storage system in a development environment. The reliability metrics we measured are availability from the standpoint of the host and maintainability from the standpoint of the system operator. We created errors using software fault injection, and measured their impact using a combination of performance measurement techniques and the rehearsal of maintenance procedures. This paper gives three case studies. The first two describe experiments that recreate very specific breakdowns in the software logic, and the third describes an experiment simulating a memory hardware failure that creates unpredictable effects. We found that, taken together, these various techniques gave us a useful picture of how well our cache management software tolerated faults.
Estimation of penalty parameters for symmetric interior penalty Galerkin methods
Authors: Yekaterina Epshteyn, Béatrice Rivière
Venue: Journal of Computational and Applied Mathematics (2007)

This paper presents computable lower bounds of the penalty parameters for stable and convergent symmetric interior penalty Galerkin methods. In particular, we derive the explicit dependence of the coercivity constants with respect to the polynomial degree and the angles of the mesh elements. Numerical examples in all dimensions and for different polynomial degrees are presented. We show the numerical effects of loss of coercivity.