ppxscal/embedding_network huggingface dataset:
SYN-MAC: a distributed medium access control protocol for synchronized wireless networks
Authors: Hongyi Wu, Anant Utgikar, Nian-Feng Tzeng
Venue: Mobile Networks and Applications (2005)

In this paper, we propose a novel medium access control (MAC) protocol, called SYN-MAC (for SYNchronized MAC), based on a binary countdown approach tailored for wireless networks. SYN-MAC has several attractive features such as simplicity, robustness, high efficiency, fairness, and quality of service capability. We evaluate SYN-MAC in terms of collision probability, system throughput, and packet delay, via both analysis and simulation. Our results show that, with properly chosen parameters, SYN-MAC can achieve a very low collision probability, packet delay tolerance, and extremely high channel efficiency (of >90%) under a wide range of traffic load. As a result, SYN-MAC may serve as an alternative to IEEE 802.11 for the wireless stations in synchronized networks.
Performance potentials of compiler-directed data speculation
Authors: Youfeng Wu, Li-Ling Chen, R. Ju, J. Fang
Venue: Proceedings of the 2003 IEEE International Symposium on Performance Analysis of Systems and Software (2003)

Compiler-directed data speculation has been implemented on Itanium systems to allow for a compiler to move a load across a store even when the two operations are potentially aliased This not only breaks data dependency to reduce critical path length, but also allows a load to be scheduled far apart from its uses to hide cache miss latencies. However, the effectiveness of data speculation is affected by the sophistication of alias analysis technique as well as the aggressiveness of the instruction scheduler. In general, the more sophisticated is the alias analysis technique, the less performance gain is from data speculation, and the more aggressive is the instruction scheduler, the more opportunity is for data speculation. In this paper we evaluate in various scenarios the performance potentials of data speculation for SPEC2000C benchmarks. For each scenario, we determine the performance contributions of data speculation due to both critical path reduction and cache miss latency reduction. We also show interesting statistics about the effects of scheduling constraints, the percentage of critical dependencies, the impacts of cache miss latencies, and the distances between the load locations before and after data speculation.
Splitting with weight windows to control the likelihood ratio in importance sampling
Authors: Pierre L'Ecuyer, Bruno Tuffin
Venue: Proceedings of the 1st international conference on Performance evaluation methodolgies and tools (2006)

Importance sampling (IS) is the most widely used efficiency improvement method for rare-event simulation. When estimating the probability of a rare event, the IS estimator is the product of an indicator function (that the rare event has occurred) by a likelihood ratio. Reducing the variance of that likelihood ratio can increase the efficiency of the IS estimator if (a) this does not reduce significantly the probability of the rare event under IS, and (b) this does not require much more work. In this paper, we explain how this can be achieved via weight windows and illustrate the idea by numerical examples. The savings can be large in some situations. We also show how the technique can backlash when the weight windows are wrongly selected.
Study on Intelligent Service Mode of Hydrological Information
Authors: CHENG Hongqi, XIE Jiancang, WANG Ni, ZHANG Yongjing, YUE Xinli
Venue: Proceedings of the 2006 International Conference on Hybrid Information Technology - Volume 01 (2006)

On the basis of agent technology, an intelligent service model for flood control decision-making support system is established. In this system, the rough sets theory is applied to execute the diagnosis and return with the individualized information for different users. This model can display the diagnosed information in the display mode specified by the user and in the display all unwanted information are eliminated. The observation data from 511 hydrological stations are used as the database to establish the intelligent service model for the hydrological information of the Yellow River.
Michael C. Jaeger
Authors: Michael C. Jaeger, Gero Muhl
Venue: Proceedings of the The 8th IEEE International Conference on E-Commerce Technology and The 3rd IEEE International Conference on Enterprise Computing, E-Commerce, and E-Services (2006)

In today's businesses we can see the trend that serviceoriented architectures (SOA) represent the main paradigm for IT infrastructures. In this setting, a software offers its functionality as an electronic service to other software in a network. In order to realise more complex tasks or business processes that are comprised of individual services, compositions of these are formed. For specific application cases such as the timedependent trading of goods or the IT-based management of natural disasters, service compositions are anticipated to provide soft real-time characteristics. Soft real-time characteristics for service compositions involve the QoS-based trading of services as well as a real-time conforming trading process that is capable of optimising the QoS in predictable and feasible amount of time. This paper will discuss the two aspects and introduce two heuristics for the QoS-aware trading that show feasible computational efforts. Based on a software simulation, the performance of these algorithms is discussed.
Learning Pathological Characteristics from User's Relevance Feedback for Content-Based Mammogram Retrieval
Authors: Chia-Hung Wei, Chang-Tsun Li
Venue: Proceedings of the Eighth IEEE International Symposium on Multimedia (2006)

Content-based image retrieval (CBIR) has been proposed to address the problem of image retrieval from medical image databases. Relevance feedback, explaining the user's query concept, can be used to bridge the semantic gap and improve the performance of CBIR systems. This paper proposes a learning method for relevance feedback, which utilizes probabilistic model to generalize the 2-class problem and provide an estimate of probability of class membership. To build the probabilistic model, support vector machine (SVM) is applied to classify the mammograms, and then scale them to the probability of class membership. Experimental results show that the proposed learning method can effectively improve the average precision rate from 40% to 62% through five iterations of relevance feedback rounds.
Reunion: Complexity-Effective Multicore Redundancy
Authors: Jared C. Smolens, Brian T. Gold, Babak Falsafi, James C. Hoe
Venue: Proceedings of the 39th Annual IEEE/ACM International Symposium on Microarchitecture (2006)

To protect processor logic from soft errors, multicore redundant architectures execute two copies of a program on separate cores of a chip multiprocessor (CMP). Maintaining identical instruction streams is challenging because redundant cores operate independently, yet must still receive the same inputs (e.g., load values and shared-memory invalidations). Past proposals strictly replicate load values across two cores, requiring significant changes to the highly-optimized core. We make the key observation that, in the common case, both cores load identical values without special hardware. When the cores do receive different load values (e.g., due to a data race), the same mechanisms employed for soft error detection and recovery can correct the difference. This observation permits designs that relax input replication, while still providing correct redundant execution. In this paper, we present Reunion, an execution model that provides relaxed input replication and preserves the existing memory interface, coherence protocols, and consistency models. We evaluate a CMP-based implementation of the Reunion execution model with full-system, cycle-accurate simulation. We show that the performance overhead of relaxed input replication is only 5% and 6% for commercial and scientific workloads, respectively.
Minimizing churn in distributed systems
Authors: P. Brighten Godfrey, Scott Shenker, Ion Stoica
Venue: Proceedings of the 2006 conference on Applications, technologies, architectures, and protocols for computer communications (2006)

A pervasive requirement of distributed systems is to deal with churn-change in the set of participating nodes due to joins, graceful leaves, and failures. A high churn rate can increase costs or decrease service quality. This paper studies how to reduce churn by selecting which subset of a set of available nodes to use.First, we provide a comparison of the performance of a range of different node selection strategies in five real-world traces. Among our findings is that the simple strategy of picking a uniform-random replacement whenever a node fails performs surprisingly well. We explain its performance through analysis in a stochastic model.Second, we show that a class of strategies, which we call "Preference List" strategies, arise commonly as a result of optimizing for a metric other than churn, and produce high churn relative to more randomized strategies under realistic node failure patterns. Using this insight, we demonstrate and explain differences in performance for designs that incorporate varying degrees of randomization. We give examples from a variety of protocols, including anycast, over-lay multicast, and distributed hash tables. In many cases, simply adding some randomization can go a long way towards reducing churn.
A ROD based Fuzzy packet loss differentiating algorithm for TCP in the hybrid wired/wireless network
Authors: Jong-Hyouk Lee, Tai-Myoung Chung
Venue: Proceedings of the International Conference on Systems and Networks Communication (2006)

A fuzzy pattern recognition loss differentiating algorithm in hybrid wired/wireless network is proposed, which distinguishes losses due to congestion from losses due to wireless error by ascribing the loss to the most likely pattern, congestion or wireless error, based on the packet ROD feature. The loss nature differentiating is a fuzzy problem, different reasons can influence the judgment at the same time, but all most the current researches take simple two values logic to this problem, so it is hard for them to get satisfying performance. In this paper, we take fuzzy pattern recognition logic on this fuzzy question based on the ROD feature of the probing packet in the loss pair. Simulation shows it performs better than the current TCP mechanism.
Approximation of SαS léy processes in Lp norm
Authors: Jakob Creutzig
Venue: Journal of Approximation Theory (2006)

We determine the weak asymptotic behavior of linear and Kolmogorov widths of the SαS Lévy process in the Banach spaces Lp, p ∈ [1, ∞) for α ∈ (0, 2). This complements earlier work by Maiorov and Wasilkowski, who treated the case α = 2, i.e., the Wiener process.
Listening to Action-related Sentences Activates Fronto-parietal Motor Circuits
Authors: Marco Tettamanti, Giovanni Buccino, Maria Cristina Saccuman, Vittorio Gallese, Massimo Danna, Paola Scifo, Ferruccio Fazio, Giacomo Rizzolatti, Stefano F. Cappa, Daniela Perani
Venue: Journal of Cognitive Neuroscience (2005)

Observing actions made by others activates the cortical circuits responsible for the planning and execution of those same actions. This observation&ndash;execution matching system (mirror-neuron system) is thought to play an important role in the understanding of actions made by others. In an fMRI experiment, we tested whether this system also becomes active during the processing of action-related sentences. Participants listened to sentences describing actions performed with the mouth, the hand, or the leg. Abstract sentences of comparable syntactic structure were used as control stimuli. The results showed that listening to action-related sentences activates a left fronto-parieto-temporal network that includes the pars opercularis of the inferior frontal gyrus (Broca's area), those sectors of the premotor cortex where the actions described are motorically coded, as well as the inferior parietal lobule, the intraparietal sulcus, and the posterior middle temporal gyrus. These data provide the first direct evidence that listening to sentences that describe actions engages the visuomotor circuits which subserve action execution and observation.
Throughput-delay analysis of interrupt-driven kernels with DMA enabled and disabled in high-speed networks
Authors: K. Salah, K. El-Badawi
Venue: Journal of High Speed Networks (2006)

Interrupt processing can be a major bottleneck in the end-to-end performance of high-speed networks. The performance of Gigabit network end hosts or servers can be severely degraded due to interrupt overhead caused by heavy incoming traffic. Under heavy network traffic, the system performance will be negatively affected due to interrupt overhead caused by the incoming traffic. In particular, excessive latency and significant degradation in system throughput can be experienced. In this paper, we present a throughput-delay analysis of such behavior. We develop analytical models based on queueing theory and Markov processes. In our analysis, we consider and model three systems: ideal, PIO, and DMA. In ideal system, the interrupt overhead is ignored. In PIO, DMA is disabled and copying of incoming packets is performed by the CPU. In DMA, copying of incoming packet is performed by DMA engines. For high-speed network hosts, both PIO and DMA can be desirable configuration options. The analysis yields insight into understanding and predicting the impact of system and network choices on the performance of interrupt-driven systems when subjected to light and heavy network loads. Simulations and reported experimental results show that our analytical models are valid and give a good approximation.
Open Hand Detection in a Cluttered Single Image using Finger Primitives
Authors: M. Baris Caglar, Niels Lobo
Venue: Proceedings of the 2006 Conference on Computer Vision and Pattern Recognition Workshop (2006)

Hand Detection plays an important role in human computer interaction (HCI) applications, as well as surveillance. We propose a hand detection technique that is robust to different skin color, illumination and shadow irregularities by exploiting the geometric properties of the hand. We first obtain the responses from two detectors that operate independently on the test image to identify parallel finger edges and curved fingertips. These responses are then grouped by using two decision trees trained on each primitive class, yielding two separate collections of groups. The final merging algorithm returns candidate hands in a given single image by comparing groups across each collection and merging those that satisfy a scoring function. The proposed system is robust to the size and the orientation of the hand, with the single requirement that one or more fingers are visible. The system is the first to successfully detect hands in an uncontrolled environment, without training on the skin color within a single image or using motion information.
Automating Climate Science: Large Ensemble Simulations on the TeraGrid with the GriPhyN Virtual Data System
Authors: Veronika Nefedova, Robert Jacob, Ian Foster, Zhengyu Liu, Yun Liu, Ewa Deelman, Gaurang Mehta, Mei-Hui Su, Karan Vahi
Venue: Proceedings of the Second IEEE International Conference on e-Science and Grid Computing (2006)

Ensemble simulations are a promising technique for identifying the signal of atmospheric response to extra-tropical sea surface temperature variability with high statistical significance. The basic idea is to perform multiple simulations from slightly different initial conditions and then to study the average signal of the ensemble. A significant obstacle to performing such ensemble simulations is the bookkeeping required to prepare, execute, and track the progress of hundreds of different computations. We describe an ensemble simulation experiment in which the Fast Ocean Atmosphere Model was run on the U.S. TeraGrid. In this experiment, we used the GriPhyN Virtual Data System to manage our ensemble simulations and their execution on distributed resources, achieving dramatic (order-of-magnitude) reductions in turnaround time relative to previous manual experiments.
Distributed Lagrangean relaxation protocol for the generalized mutual assignment problem
Authors: Katsutoshi Hirayama
Venue: Proceedings of the fifth international joint conference on Autonomous agents and multiagent systems (2006)

We present a new formulation of distributed task assignment, Generalized Mutual Assignment Problem (GMAP), which is derived from a typical NP-hard combinatorial optimization problem that has been studied for many years mainly in the operations research community. Then, to solve the GMAP, we introduce a novel distributed solution protocol using Lagrangean decomposition and distributed constraint satisfaction, where the agents solve their individual optimization problems and coordinate their locally optimized solutions through a distributed constraint satisfaction technique. Next, to produce quick agreement between the agents on a feasible solution with reasonably good quality, we provide a parameter that controls the range of "noise" mixed with increment/decrement in a Lagrangean multiplier and report our experimental results indicating that the parameter may allow us to control tradeoffs between the quality of a solution and the cost of finding it.
An Abandoned/Removed Objects Detection Algorithm and Its Evaluation on PETS Datasets
Authors: Paolo Spagnolo, Andrea Caroppo, Marco Leo, Tommaso Martiriggiano, Tiziana D'Orazio
Venue: Proceedings of the IEEE International Conference on Video and Signal Based Surveillance (2006)

In this paper, a new method for a robust and efficient analysis of video sequences is presented; it allows the extraction of foreground objects and the classification of static foreground regions as abandoned or removed objects (ghosts). As a first step, the moving regions in the scene are detected by subtracting to the current frame a background model continuously adapted. Then, a shadow removing algorithm is used to extract the real shape of detected objects. Finally, moving objects are classified as abandoned or removed by matching the boundaries of static foreground regions. The method was successfully tested on both real image sequences acquired in our laboratory and some sequences from the PETS 2006 Datasets.
Regularizing generalized linear systems by means a derivative feedback
Authors: M. I. Garcia-Planas
Venue: Proceedings of the 2003 International Conference on Physics and Control - Volume 4 (2003)

We consider generalized linear time invariant systems in the form Ex(t) = Ax(t) + Bu(t) with E, A /spl isin/ M/sub n/spl times/m/(/spl Copf/), B /spl times/ M/sub n/spl times/m/(/spl Copf/), arising naturally in a variety of circumstances fro example they are used in modelling of mechanical multibody system. Obviously, the regularity condition det E /spl ne/ 0 guarantees the existence and uniqueness of solutions. In this work we study necessary and sufficient conditions in order that the matrix E can be regularized by means of a derivative feedback, that is to say conditions that ensure the existence if a control u(t) = -Vx/spl dot/(t) + w(t) with V /spl isin/ M/sub n/spl times/m/(/spl Copf/) such that the matrix E + BV in the closed loop system (E + BV)x/spl dot/(t) = Ax(t) + Bw(t) is regular and consequently the closed loop system is uniquely solvable. We also study conditions for controllability of the closed loop system ensuring the existence of feedback w(t) = Ux(t) + w(t) with V /spl isin/ M/sub n/spl times/m/(/spl Copf/), such that the system (E + BV)x/spl dot/(t) = (A + BU)x(t) + Bw(t) has a stable solution. Finally, a stratification of the space of orbits of the systems that can be regularized is presented.
Optimization of Dual-Speed TAM Architectures for Efficient Modular Testing of SOCs
Authors: Anuja Sehgal, Krishnendu Chakrabarty
Venue: IEEE Transactions on Computers (2007)

The increasing complexity of system-on-chip (SOC) integrated circuits has spurred the development of versatile automatic test equipment (ATE) that can simultaneously drive different channels at different data rates. Examples of such ATEs include the Agilent 93000 series tester based on port scalability and the test processor-per-pin architecture and the Tiger system from Teradyne. The number of tester channels with high data rates may be constrained in practice, however, due to ATE resource limitations, the power rating of the SOC, and scan frequency limits for the embedded cores. Therefore, we formulate the following optimization problem: Given two available data rates for the tester channels, an SOC-level test access mechanism (TAM) width W, an upper limit V (V
Blurring the lines: learning and assessing in quadrant D some key lessons from four successive years of embedded assessment design in our sustainable earth project
Authors: Ken Rose, Martin Block
Venue: Proceedings of the 7th international conference on Learning sciences (2006)

This design paper describes some of the main characteristics of four successive iterations of an embedded assessment activity used in our annual "Sustainable Earth" project. The details shared here come mainly from a comparative analysis of our last two assessment design cycles, highlighting differences between two common activity structures: a culminating student presentation and a global summit debate. We found that reframing the task and attending to a few specific elements of the teachers' and students' roles both before and during the activity resulted in two significant impacts. First, the debate activity transformed the student learning that took place in terms of its rigor and relevance, making it more characteristic of what we describe as "Quadrant D learning." Second, the debate greatly increased our teachers' ability to assess their students' learning of desired content and skills, making it an even more effective embedded assessment activity than the final presentation alone.
Biomedical computing and visualization
Authors: Chris R. Johnson, David M. Weinstein
Venue: Proceedings of the 29th Australasian Computer Science Conference - Volume 48 (2006)

Computers have changed the way we live, work, and even recreate. Now, they are transforming how we think about and treat human disease. In particular, advanced techniques in biomedical computing, imaging, and visualization are changing the face of biology and medicine in both research and clinical practice. The goals of biomedical computing, imaging and visualization are multifaceted. While some images and visualizations facilitate diagnosis, others help physicians plan surgery. Biomedical simulations can help to acquire a better understanding of human physiology. Still other biomedical computing and visualization techniques are used for medical training. Within biomedical research, new computational technologies allow us to "see" into and understand our bodies with unprecedented depth and detail. As a result of these advances, biomedical computing and visualization will help produce exciting new biomedical scientific discoveries and clinical treatments. In this paper, we give an overview of the computational science pipeline for an application in neuroscience and present associated research results in medical imaging, modeling, simulation, and visualization [1].