ppxscal/embedding_network huggingface dataset:
Average-case performance analysis of scheduling random parallel tasks with precedence constraints on mesh connected multicomputer systems
Authors: Keqin Li
Venue: Journal of Parallel and Distributed Computing (2006)

We investigate the problem of scheduling parallel tasks with precedence constraints on mesh connected multicomputer systems. It is still an open problem on whether there exists an approximation algorithm with finite asymptotic worst-case and/or average-case performance bound for this scheduling problem. As an early attempt to solve our problem, we propose and analyze the performance of a level-by-level scheduling algorithm LL. In fact, we solve a special case of the problem when all tasks request for square submeshes and run on a square mesh system whose size is a power of 2. There are three basic techniques in algorithm LL, i.e., the level-by-level scheduling strategy for handling precedence constraints, the largest-task-first algorithm for scheduling tasks in the same level, and the two-dimensional buddy system for system partitioning and processor allocation. Algorithm LL does not have a finite worst-case performance bound; however, it has quite acceptable average-case performance. The main contribution of the paper is to show that under the assumptions that task sizes are independent and identically distributed (i.i.d.) random variables with a common probability distribution, and that task execution times are i.i.d. random variables with finite mean and variance, and that the probability distributions of task sizes and execution times are independent of each other, for wide task graphs and typical task size distributions, algorithm LL has an asymptotic average-case performance bound about two for all probability distributions of task execution times.
Performance analysis using CPN tools
Authors: Lisa Wells
Venue: Proceedings of the 1st international conference on Performance evaluation methodolgies and tools (2006)

This paper provides an overview of new facilities for performance analysis using Coloured Petri Nets and the tool CPN Tools. Coloured Petri Nets is a formal modeling language that is well suited for modeling and analyzing large and complex systems. The new facilities include support for collecting data during simulations, for generating different kinds of performance-related output, and for running multiple simulation replications. A simple example of a network protocol is used to illustrate the flexibility of the new facilities.
Enhancing design education for engineering students: supporting planning, tracking, and reflection
Authors: Jennifer Turns
Venue: Proceedings of the 1996 international conference on Learning sciences (1996)

In my research, I am concerned with the issue of enhancing the learning that arises out of project experiences, specifically the learning of engineering design from term-long, group project experiences. Within this context, I have two goals. My first goal is to understand the types of problems which arise in learning engineering design in such contexts and to develop a framework for describing these problems. My second goal is to design, develop and evaluate activity structures and associated technology resources that address the problems that arise with respect to learning in these contexts. In particular, I am exploring how the activities of planning and tracking, performed within a specially designed environment, can be incorporated into the project experiences in order to help learners recognize and capitalize on learning opportunities that arise naturally from the project experience.
From mechanical to meaningful classroom questions
Authors: Elizabeth S. Charles, Sabina Karkin, Christopher Kramer, Janet L. Kolodner
Venue: Proceedings of the 7th international conference on Learning sciences (2006)

While observing two project-based inquiry classrooms, we noticed and became intrigued by the markedly different development of science discourse practices across the two classes. Both were taught by the same teacher, used the same curriculum materials, engaged in the same learning activities, and were comprised of equally engaged and high achieving honors students. Yet over a 20-week period, the question-asking and answering practices of students in the two classes diverged considerably. While students in Class A were still struggling to adopt the practices modeled by the teacher, students in Class B were taking the initiative to ask each other to explain trends identified in investigations and working out explanations together. Investigating differences between these two near-identical enactments has allowed us to identify changes in question-asking practices that lead to productive interpretations and science discourse. We offer explanations for the differences between the classes and for the changes observed over time.
PD-type controller in terms of generalized velocity components
Authors: P. Herman
Venue: International Journal of Robotics and Automation (2006)

In this paper the usefulness of equations of motion expressed in terms of generalized velocity components (GVC)is considered. Based on these equations, a PD-type controller for a rigid serial manipulator is proposed. The GVC differ from well-known quasi-velocities because they contain both kinematics and dynamics parameters of the system. Introducing GVC allows us to obtain two first-order differential equations instead of one second-order equation. As a consequence, the controller in terms of GVC is decoupled. Additionally, some interesting features are observable if the GVC controller is used. They arise from the fact that some quantities can be determined for each joint or for each link individually.
A Novel Matrix Norm Based Gaussian Kernel for Feature Extraction of Images
Authors: Jun-Bao Li, Shu-Chuan Chu, Jeng-Shyang Pan, Jiun-Huei Ho
Venue: Proceedings of the 2006 International Conference on Intelligent Information Hiding and Multimedia (2006)

Gaussian kernel is widely used in Support Vector Machines and many other kernel methods, and it is most often deemed to provide a local measure of similarity between vectors, which causes large storage requirements and large computational effort for transforming images to vectors owing to its viewing images as vectors. A novel matrix norm based Gaussian kernel (M-Gaussian kernel) which views images as matrices is proposed to solve the problem. Experiments conducted on ORL face database show the effectiveness of the proposed M-Gaussian kernel.
A garbage-collecting typed assembly language
Authors: Chris Hawblitzel, Heng Huang, Lea Wittie, Juan Chen
Venue: Proceedings of the 2007 ACM SIGPLAN international workshop on Types in languages design and implementation (2007)

Typed assembly languages usually support heap allocation safely, but often rely on an external garbage collector to deallocate objects from the heap and prevent unsafe dangling pointers. Even if the external garbage collector is provably correct, verifying the safety of the interaction between TAL programs and garbage collection is nontrivial. This paper introduces a typed assembly language whose type system is expressive enough to type-check a Cheney-queue copying garbage collector, so that ordinary programs and garbage collection can co-exist and interact inside a single typed language. The only built-in types for memory are linear types describing individual memory words, so that TAL programmers can define their own object layouts, method table layouts, heap layouts, and memory management techniques.
Histogram-based image retrieval using Gauss mixture vector quantization
Authors: Sangoh Jeong, R. M. Gray
Venue: Proceedings of the 2003 International Conference on Multimedia and Expo - Volume 1 (2003)

Histogram-based image retrieval requires some form of quantization since the raw color images result in large dimensionality in the histogram representation. Simple uniform quantization disregards the spatial information among pixels in making histograms. Since traditional vector quantization (VQ) with squared-error distortion employs only the first moment, it neglects the relationship among vectors. We propose Gauss mixture vector quantization (GMVQ) as the quantization method for a histogram-based image retrieval to capture the spatial information in the image via the Gaussian covariance structure. Two common histogram distance measures are used to evaluate the similarity of histograms resulting from GMVQ. Our result shows that GMVQ with a quadratic discriminant analysis (QDA) distortion outperforms the two typical quantization methods in the histogram- based image retrieval.
Iterated integrals, Gelfand-Leray residue, and first return mapping
Authors: J.-P. Françoise, M. Pelletier
Venue: Journal of Dynamical and Control Systems (2006)

Recently, one of the authors gave an algorithm for calculating the first nonzero Poincaré-Pontryagin function of a small polynomial perturbation of a polynomial Hamiltonian, under a generic hypothesis. We generalize this algorithm and show that any Poincaré-Pontryagin function of order l, denoted by Ml, can be written as a sum of an iterated integral of length at most l and of a combination of all previous Poincaré-Pontryagin functions, M1, M2,...,Ml-1, and their derivatives. This extends some results obtained recently and allows to identify the Bautin ideal with the ideal generated by iterated integrals.
An Energy-Efficient and Access Latency Optimized Indexing Scheme for Wireless Data Broadcast
Authors: Yuxia Yao Xueyan Tang, Ee-Peng Lim, Aixin Sun
Venue: IEEE Transactions on Knowledge and Data Engineering (2006)

Data broadcast is an attractive data dissemination method in mobile environments. To improve energy efficiency, existing air indexing schemes for data broadcast have focused on reducing tuning time only, i.e., the duration that a mobile client stays active in data accesses. On the other hand, existing broadcast scheduling schemes have aimed at reducing access latency through nonflat data broadcast to improve responsiveness only. Not much work has addressed the energy efficiency and responsiveness issues concurrently. This paper proposes an energy-efficient indexing scheme called MHash that optimizes tuning time and access latency in an integrated fashion. MHash reduces tuning time by means of hash-based indexing and enables nonflat data broadcast to reduce access latency. The design of hash function and the optimization of bandwidth allocation are investigated in depth to refine MHash. Experimental results show that, under skewed access distribution, MHash outperforms state-of-the-art air indexing schemes and achieves access latency close to optimal broadcast scheduling.
KawaWiki: A Semantic Wiki Based on RDF Templates
Authors: Kensaku Kawamoto, Yasuhiko Kitamura, Yuri Tijerino
Venue: Proceedings of the 2006 IEEE/WIC/ACM international conference on Web Intelligence and Intelligent Agent Technology (2006)

A Semantic Wiki is a collaborative Semantic Web authoring system based on the Wiki framework. It provides a scheme where anonymous users on the Internet can collaborate with each other to build a Semantic Web site. Contrasting to traditional Wikis, it is not easy for end users to author Semantic Wiki pages from scratch without knowledge of the complex RDF/OWL syntax and of ontologies to share semantic information. We propose a new Semantic Wiki system called "KawaWiki" on which end and expert users can collaborate to build a Semantic Web site. KawaWiki generates RDF and Wiki pages based on its RDF templates and validates their consistency with the RDFS description. The RDFS description can be created by importing Web ontologies on the Internet. KawaWiki aims at providing a scheme where end users, expert users and ontologists seamlessly collaborate to publish semantically consistent RDF and Wiki pages in a Wiki way.
Information Hiding Method in Digital Audio Signal Based on Perfect Codes
Authors: Lin-na Zhou, Cui-qing Liu, Xi-jian Ping, Tao Zhang, Yun-he Wang
Venue: Proceedings of the 2006 International Conference on Intelligent Information Hiding and Multimedia (2006)

A novel information hiding method in digital audio signal by using the encoding redundancy of perfect codes is presented in this paper. Researches on perfect codes and its syndrome of the codeword show that the syndrome of a codeword depends only on the error, not on the codeword transmitting. A mapping encoding between secret message and codeword error map is built. According to the error map, we can embed secret messages by modifying the codeword of perfect codes. In this paper we propose a particular example of perfect codes that carrying secret messages with its encoding redundancy. Theoretical analysis and experimental results show that this method has good security.
Incentive compatible medium access control in wireless networks
Authors: Nassir BenAmmar, John S. Baras
Venue: Proceeding from the 2006 workshop on Game theory for communications and networks (2006)

The current IEEE 802.11 medium access control standard is being deployed in coffee shops, in airports and even across major cities. The terminals accessing these wi-fi access points do not belong to the same entity, as in corporate networks, but are usually individually owned and operated. Entities sharing these network resources have no incentive in following protocol rules other than to optimize their overall utility, usually a function of throughput and delay. We briefly discuss shortfalls of the current IEEE 802.11 standard in environments where terminals are competing for a common bandwidth resource, and then we introduce a new MAC protocol designed with the above considerations. Thus the new Incentive Compatible MAC (ICMAC) protocol is more suited for these open environments, without compromising the overall network performance.
Adopting Model-Driven Development for Integrated Services and Appliances in Home Network Systems
Authors: Hiroshi Igaki, Masahide Nakamura, Ken-ichi Matsumoto, Mikio Aoyama
Venue: Proceedings of the XIII Asia Pacific Software Engineering Conference (2006)

The technology of a home network system (HNS) allows integration of several kinds of home appliances to provide a user with value-added integrated services. Development of the integrated HNS services requires implementation of the appliance components (with APIs) and the services, according to each home-network environment. There are various implementation standards such as DLNA, ECHONET, OSGi and Jini for the HNS applications. Therefore, even if a developer can choose the optimal one, it's very difficult to develop the integrated services by composing a new HNS implementation. In this paper, we propose a model-driven development of integrated HNS service applications. In our former manuscript, platform-independent design language for verifying HNS service scenarios was proposed. Our model-driven developmentmethod uses this design language as a meta-model of integrated HNS services. By model transformation to concrete implementation together with verification by SMV(Symbolic Model Checking), productivity and quality of this kind of HNS applications are improved.
Distributed Multimedia Streaming Systems in Peer-to-Peer Overlay Networks
Authors: Tomoya Enokido, Youhei Tanaka, Valbona Barolli, Makoto Takizawa
Venue: Proceedings of the Eighth IEEE International Symposium on Multimedia (2006)

A multimedia contents are distributed to peers and a contents peer which holds contents can provide other peers with the contents in peer-to-peer (P2P) overlay networks. Multimedia streaming is more significant than downloading ways in multimedia applications from security and economical reasons. We discuss distributed multi-source streaming models. Here, a collection of multiple contents peers in parallel transmit packets of a multimedia content to a leaf peer to realize the reliability and scalability. Even if not only some number of peers stop by fault and are degraded in performance but also some number of packets are lost and delayed, a leaf peer can receive a content at the required rate. We discuss how to allocate packets to each contents peer. We discuss a gossip-based, DAG-based coordination protocol (DCoP) to synchronize multiple contents peers. We evaluate DCoP in terms of how long it takes and how many messages are transmitted to synchronize multiple contents peers.
P-tree structures and event horizon: efficient event-set implementations
Authors: Katerina Asdre, Stavros D. Nikolopoulos
Venue: Proceedings of the 37th conference on Winter simulation (2005)

This paper describes efficient data structures, namely the Indexed P-tree, Block P-tree, and Indexed-Block P-tree (or IP-tree, BP-tree, and IBP-tree, respectively, for short), for maintaining future events in a general purpose discrete event simulation system, and studies the performance of their event set algorithms under the event horizon principle. For comparison reasons, some well-known event set algorithms were also selected and studied; that is, the Dynamic-heap and the P-tree algorithms. To gain insight into the performance of the proposed event set algorithms and allow comparisons with the other selected algorithms, they are tested under a wide variety of conditions in an experimental way. The time needed for the execution of the Hold operation is taken as the measure for estimating the average time complexity of the algorithms. The experimental results show that the BP-tree algorithm and the IBP-tree algorithm behave very well with all the sizes of the event set and their performance is almost independent from the stochastic distributions.
Experimental investigation of the impacts of virtual reality on discrete-event simulation
Authors: Justice I. Akpan, Roger J. Brooks
Venue: Proceedings of the 37th conference on Winter simulation (2005)

This paper presents the results of experimental studies that were undertaken to test the impacts of Virtual Reality (VR) on Discrete-Event Simulation (DES). The experiments focused on spotting errors in the DES model. The models were developed in 2D and 3D/VR displays using WITNESS. The 2D display used icons and other visualization techniques that confine its scope to essentially flat 2D surface. On the other hand, the 3D display was represented by means of a three-axis spatial position (XYZ) plots, but appeared on a two-dimensionally mappings, otherwise known as 2.5D. The experiments involved paid participants who were recruited from amongst the staff and students of Lancaster University, UK. The results showed that it is easier, and faster to spot errors in 3D/VR model than in 2D. The findings also indicated that users can easily understand the modeled operation of 3D/VR display compared to 2D, irrespective of background or technical ability.
Available Bandwidth Estimation in IEEE802.11b Network Based on Non-Intrusive Measurement
Authors: Chen Chen, Changxing Pei, Liunai An
Venue: Proceedings of the Seventh International Conference on Parallel and Distributed Computing, Applications and Technologies (2006)

In this paper,we present a non-intrusive and timebased mechanism to estimate the available bandwidth of a node with the nodes collision and backoff stage taken into account. We first give a new definition of available bandwidth in IEEE802.11b network to reflect the collision and contention between nodes.Then,the investigated node obtains the NAV information of its neighbors within the measurement duration through CSMA/CA mechanism and stores the information into its routing buffers.Subsequently,we obtain the available bandwidth of the investigated node by calculate the ratio of its channel accessible time to the measurement duration,which should subtract the sum of NAV values of its neighbors and the backoff time itself from the measurement duration.Simulation shows the proposed scheme is accurate and can completely reflect the collision and contention between nodes.
On the convergence enhancment of the wavelet transform based LMS
Authors: S. Attallah, M. Najim
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1995. on International Conference - Volume 02 (1995)

The wavelet transform least mean squares algorithm (WTLMS) has been recently proposed as an alternative to the simple and transform based (DCT) LMS algorithms, because of its faster convergence. In this paper, we first show the influence of the regularity of the wavelet low-pass filter on the convergence behavior of the normalized WTLMS algorithm (NWTLMS). Then, we show that the subband decomposition of the input signal along a regular subband tree, which splits the signal frequency band uniformly, gives better results, i.e., a faster convergence rate than the dyadic subband tree, which splits the signal frequency band dyadically. Finally, we show that perfect reconstruction quadrature mirror filters (PR-QMFs), which are less regular, can lead to as good results while the multiplier-free PR-QMFs offer, furthermore, a very reduced computational complexity, and hence can be used as an alternative to the wavelet filters for accelerating the convergence rate of the NWTLMS algorithm.
Enhancing virtual reality with artificial life: reconstructing a flooded European mesolithic landscape
Authors: Eugene Ch'ng, Robert J. Stone
Venue: Presence: Teleoperators and Virtual Environments (2006)

The fusion of Virtual Reality and Artificial Life technologies has opened up a valuable and effective technique for research in the field of dynamic archaeological reconstruction. This paper describes early evaluations of simulated vegetation and environmental models using decentralized Artificial Life entities. The results demonstrate a strong feasibility for the application of integrated VR and Artificial Life in solving a 10,000 year old mystery shrouding a submerged landscape in the Southem North Sea, off the east coast of the United Kingdom. Three experimental scenarios with dynamic, "artificial" vegetation are observed to grow, reproduce, and react to virtual environmental parameters in a way that mimics their physical counterparts. Through further experimentation and refinement of the Artificial Life rules, plus the integration of additional knowledge from subject matter experts in related scientific fields, a credible reconstruction of the ancient and, today, inaccessible landscape may be within our reach.
Spatial Divide and Conquer with Motion Cues for Tracking through Clutter
Authors: Zhaozheng Yin, Robert Collins
Venue: Proceedings of the 2006 IEEE Computer Society Conference on Computer Vision and Pattern Recognition - Volume 1 (2006)

Tracking can be considered a two-class classification problem between the foreground object and its surrounding background. Feature selection to better discriminate object from background is thus a critical step to ensure tracking robustness. In this paper, a spatial divide and conquer approach is used to subdivide foreground and background into smaller regions, with different features being selected to distinguish between different pairs of object and background regions. Temporal cues are incorporated into the process using foreground motion prediction and motion segmentation. Appearance weight maps tailored to each spatial region are merged and combined with the motion information to form a joint weight image suitable for mean-shift tracking. Examples are presented to illustrate that divide and conquer feature selection combined with motion cues handles spatial background clutter and camouflage well.