ppxscal/embedding_network huggingface dataset:
Top-Down Approach to Segmentation of Prostate Boundaries in Ultrasound Images
Authors: Ahmed Jendoubi, Jianchao Zeng, Mohamed F. Chouikha
Venue: Proceedings of the 33rd Applied Imagery Pattern Recognition Workshop (2004)

Ultrasound has been increasingly used in surgical procedures of the prostate in recent years. Segmentation of prostate boundaries from ultrasound images is clinically useful in such situations as accurate volume measurement, and tumor margin estimation, and it can also provide real-time targeted image guidance during procedures such as biopsy and ablation. Automatic segmentation of the prostate, however, is a challenging task since the ultrasound images usually have high level of speckle noises due to large amount of random scatters and thus they have a very low signal-to-noise ratio. As a result, physicians have to use manual methods to draw contours of the prostate, slice by slice, in order to calculate prostate volume information. This is a tedious work and apparently it delays the whole clinical procedures. In addition, accuracy of the segmented prostate boundaries cannot be guaranteed due to significant variations among different physicians or with the same physician at different times.In this paper, we will present a top-down approach to the segmentation of prostate ultrasound images using a snake model, as compared to most existing bottom-up methods. Special measures were taken to deal with the high speckle noises and complex shapes of prostate boundaries. In general, median filtering proved to be effective in removing speckle noises. We extensively evaluated most of the existing edge detection methods and found that the logic combination of Laplacian of Gaussian (LoG) and Sobel operator provided the best performance in finding the useful image gradients. Parameters of the snake were dynamically optimized, and the shape information of the prostate was used as a strong guidance during the deformation process of the snake model. Experimental results with several ultrasound prostate images with various levels of noises were presented to demonstrate the effectiveness of the proposed approach.
Global software development at siemens: experience from nine projects
Authors: James D. Herbsleb, Daniel J. Paulish, Matthew Bass
Venue: Proceedings of the 27th international conference on Software engineering (2005)

We report on the experiences of Siemens Corporation in nine globally-distributed software development projects. These projects represent a range of collaboration models, from co-development to outsourcing of components to outsourcing the software for an entire project. We report experience and lessons in issues of project management, division of labor, ongoing coordination of technical work, and communication. We include lessons learned, and conclude the paper with suggestions about important open research issues in this area.
Analysis of the limitations of multiple client handling in a Java server environment
Authors: Simon Beloglavec, Marjan Heričko, Matjaž B. Jurič, Ivan Rozman
Venue: ACM SIGPLAN Notices (2005)

A server infrastructure in web servers, message servers and other parallel systems use a variation of two software architectures for providing concurrency: threaded or event-driven. This paper analyzes the performance limitations of concurrent applications implemented in Java. Both architectures have been evaluated and compared with various design patterns, which combine the best practices from both architectures. For each architecture the suitability for handling a large volume of client requests, the efficient management of a server load, the influence of client request structures, and the physical size of a client request, have been studied. The discussed Java APIs are core technologies for high-level APIs, used in developing web and distributed applications. The research also includes performance comparison on various platforms and discusses performance variation on various versions of a Java runtime. The paper contributes to the understanding of Java-based server architecture capabilities. Core server software architectures and required Java libraries are compared, the reasons for the limitations are identified and guidelines for choosing proper combinations are given.
CoDIMS: an adaptable middleware system for scientific visualization in Grids: Research Articles
Authors: F. Porto, G. Giraldi, J. C. Oliveira, R. Silva, B. Schulze
Venue: Concurrency and Computation: Practice Experience (2004)

In this paper we propose a middleware infrastructure adapted for supporting scientific visualization applications over a Grid environment. We instantiate a middleware system from CoDIMS, which is an environment for the generation of configurable data integration middleware systems. CoDIMS adaptive architecture is based on the integration of special components managed by a control module that executes users workflows. We exemplify our proposal with a middleware system generated for computing particles' trajectories within the constraints imposed by a Grid environment. Copyright &copy; 2004 John Wiley & Sons, Ltd.
Reconfigurable Object Consistency Model
Authors: Christiane V. Pousa, Luis F. W. Goes, Carlos A. P. S. Martins
Venue: Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Workshop 8 - Volume 09 (2005)

Consistency is an important issue in Distributed Shared Memory (DSM) systems. These systems share a set of objects or virtual memory pages. The data sharing enables the applications in workloads to access the data concurrently. But, these concurrent accesses can generate some inconsistencies in the shared data state. The consistency models are responsible for managing consistency of shared data for the workloads. In this work, we propose, present and analyze a reconfigurable consistency model for object based DSMs. We called this consistency model ROCoM (Reconfigurable Object Consistency Model). ROCoM behavior was represented using a reconfigurable algorithm (RA) and it analysis was made using a simulation tool (ClusterSim - Cluster Simulation Tool). Our results show that ROCoM, on average, had 55% better performance than the other traditional consistency models.
Hidden challenges on teaching web software engineering
Authors: Katia Passos, Eric Freeman, Cerise Wuthrich, Catherine Stringfellow
Venue: Journal of Computing Sciences in Colleges (2004)

The evolution of data communication technology has increased Internet traffic with negative effects on the user's response time. An existing mechanism to combat such effect is Web caching, in which intermediary systems are used to temporarily store information that may be retrieved by multiple users or by a same user multiple times. Software engineers, designing applications for this new environment, depend on techniques that emphasize the satisfaction of the users' requirements and the availability of computing resources on the processing site. However, software engineering classes may be overlooking some of these problems. In this paper, caching problems related to Web applications are presented. Knowing these problems exist is important in software engineering web-based applications.
Evolution of Neural Architecture Fitting Environmental Dynamics
Authors: Genci Capi, Kenji Doya
Venue: Adaptive Behavior - Animals, Animats, Software Agents, Robots, Adaptive Systems (2005)

Temporal and sequential information is essential to any agent continually interacting with its environment. In this paper, we test whether it is possible to evolve a recurrent neural network controller to match the dynamic requirement of the task. As a benchmark, we consider a sequential navigation task where the agent has to alternately visit two rewarding sites to obtain food and water after first visiting the nest. To achieve a better fitness, the agent must select relevant sensory inputs and update its working memory to realize a non-Markovian sequential behavior in which the preceding state alone does not determine the next action. We compare the performance of a feed-forward and recurrent neural control architectures in different environment settings and analyze the neural mechanisms and environment features exploited by the agents to achieve their goal. Simulation and experimental results using the Cyber Rodent robot show that a modular architecture with a locally excitatory recur rent layer outperformed the general recurrent controller.
Distributed Shared Arrays: An Integration of Message Passing and Multithreading on SMP Clusters
Authors: Ramzi Basharahil, Brian Wims, Cheng-Zhong Xu, Song Fu
Venue: The Journal of Supercomputing (2005)

This paper presents a Distributed Shared Array runtime system to support Java-compliant multithreaded programming on clusters of symmetric multiprocessors (SMPs). As a hybrid of message passing and shared address space programming models, the DSA programming model allows programmers to explicitly control data distribution so as to take advantage of the deep memory hierarchy, while relieving them from error-prone orchestration of communication and synchronization at run-time. The DSA system is developed as an integral component of mobility support middleware for grid computing so that DSA-based virtual machines can be reconfigured to adapt to the varying resource supplies or demand over the course of a computation. The DSA runtime system also features a directory-based cache coherence protocol in support of replication of user-defined sharing granularity and a communication proxy mechanism for reducing network contention. We demonstrate the programmability of the model in a number of parallel applications and evaluate its performance on a cluster of SMP servers, in particular, the impact of the coherence granularity.
Opinion observer: analyzing and comparing opinions on the Web
Authors: Bing Liu, Minqing Hu, Junsheng Cheng
Venue: Proceedings of the 14th international conference on World Wide Web (2005)

The Web has become an excellent source for gathering consumer opinions. There are now numerous Web sites containing such opinions, e.g., customer reviews of products, forums, discussion groups, and blogs. This paper focuses on online customer reviews of products. It makes two contributions. First, it proposes a novel framework for analyzing and comparing consumer opinions of competing products. A prototype system called Opinion Observer is also implemented. The system is such that with a single glance of its visualization, the user is able to clearly see the strengths and weaknesses of each product in the minds of consumers in terms of various product features. This comparison is useful to both potential customers and product manufacturers. For a potential customer, he/she can see a visual side-by-side and feature-by-feature comparison of consumer opinions on these products, which helps him/her to decide which product to buy. For a product manufacturer, the comparison enables it to easily gather marketing intelligence and product benchmarking information. Second, a new technique based on language pattern mining is proposed to extract product features from Pros and Cons in a particular type of reviews. Such features form the basis for the above comparison. Experimental results show that the technique is highly effective and outperform existing methods significantly.
Improving involvment in a groupware system
Authors: Guillaume Durand, Laurence Vignollet
Venue: Proceedings of the 15th French-speaking conference on human-computer interaction on 15eme Conference Francophone sur l'Interaction Homme-Machine (2003)

This paper deals with the problem of the engagement of individuals in a mediatized joint activity. After introducing this problem and the social aspects that it raises, we are concerned with the solutions brought to this problem in online communities. Lastly, we describe our approach based on the intervention of a software agent, the mediator, resulting from an organizational model : the participation model.
Trust in multi-agent systems
Authors: Sarvapali D. Ramchurn, Dong Huynh, Nicholas R. Jennings
Venue: The Knowledge Engineering Review (2004)

Trust is a fundamental concern in large-scale open distributed systems. It lies at the core of all interactions between the entities that have to operate in such uncertain and constantly changing environments. Given this complexity, these components, and the ensuing system, are increasingly being conceptualised, designed, and built using agent-based techniques and, to this end, this paper examines the specific role of trust in multi-agent systems. In particular, we survey the state of the art and provide an account of the main directions along which research efforts are being focused. In so doing, we critically evaluate the relative strengths and weaknesses of the main models that have been proposed and show how, fundamentally, they all seek to minimise the uncertainty in interactions. Finally, we outline the areas that require further research in order to develop a comprehensive treatment of trust in complex computational settings.
Reflection Components Decomposition of Textured Surfaces Using Linear Basis Functions
Authors: Robby T. Tan, Katsushi Ikeuchi
Venue: Proceedings of the 2005 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR'05) - Volume 1 - Volume 01 (2005)

Most existing methods of reflection components decomposition using a single color image require color segmentation. Few methods that employ local operations are able to avoid the requirement; however, they usually suffer from color discontinuity problems. In this paper, we introduce a decomposition method using a single color image that does not require (global) color segmentation or (local) color discontinuity detection. The method principally utilizes the coefficients of the reflectance basis functions of input image and its specular-free image. Combining those coefficients enables us to find the diffuse coefficients of the specular pixels for every surface color. As a result, the decomposition becomes a well-posed problem and able to be solved in closed-form equations. Our experimental results on real complex textured images show the effectiveness of our proposed method.
Geo-Consistency for Wide Multi-Camera Stereo
Authors: Marc-Antoine Drouin, Martin Trudeau, Sebastien Roy
Venue: Proceedings of the 2005 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR'05) - Volume 1 - Volume 01 (2005)

This paper presents a new model to overcome the occlusion problems coming from wide baseline multiple camera stereo. Rather than explicitly modeling occlusions in the matching cost function, it detects occlusions in the depth map obtained from regular efficient stereo matching algorithms. Occlusions are detected as inconsistencies of the depth map by computing the visibility of the map as it is reprojected into each camera. Our approach has the particularity of not discriminating between occluders and occludees. The matching cost function is modified according to the detected occlusions by removing the offending cameras from the computation of the matching cost. The algorithm gradually modifies the matching cost function according to the history of inconsistencies in the depth map, until convergence. While two graph-theoretic stereo algorithms are used in our experiments, our framework is general enough to be applied to many others. The validity of our framework is demonstrated using real imagery with different baselines.
The High Performance Embedded Computing Software Initiative: C++ and Parallelism Extensions to the Vector, Signal, and Image Processing Library Standard
Authors: Dan Campbell
Venue: Proceedings of the 2004 Users Group Conference (2004)

The High Performance Embedded Computing Software Initiative (HPEC-SI) program is developing a unified computation and communication Application Programming Interface (API) and framework for high performance signal processing tasks on parallel computers. The goalof the program is to address the high cost of software in Department of Defense (DoD)systems by improving the portability and productivity of signal processing application development threefold, while improving performance by one half compared to current practices. This paper describes the motivation for the HPEC-SI program, its goals and approaches, and progress of the HPEC-SI Working Groups in extending the Vector, Signal, and Image Processing Library (VSIPL) standard to C++ and transparent operation in parallel computing systems. The current draft version of the C++ extensions to VSIPL is described,and highlights of its advantages are considered. This paper also examines results from the Demonstration Working Group, and describes requirements and plans developed by the Applied Research Working Group for data parallel extensions to VSIPL and describes Development Working Group progress so far in developing parallel VSIPL.
High Performance Constraint Satisfaction Problem Solving: State-Recomputation versus State-Copying
Authors: Jigang Yang, Scott D. Goodwin
Venue: Proceedings of the 19th International Symposium on High Performance Computing Systems and Applications (2005)

Constraint Satisfaction Problems (CSPs) in Artificial Intelligence have been an important focus of research and have been a useful model for various applications. Most CSP solving techniques rely on a single processor. With the increasing popularization of multiple processors, parallel search methods are becoming alternatives to speed up search processing. In this paper, we present a forward checking algorithm that solves non-binary CSPs by distributing different branches of the search tree to different processors, i.e., an OR-parallel approach. However, the problem is how to efficiently communicate the state of the search among processors. Two parallel communication models, namely, state-recomputation and state-copying via message passing, are implemented and evaluated. The experimental results demonstrate that when constraints are tight, the state-recomputation model has better performance than the state-copying model, but when constraints are loose, the state-copying model is a better choice.
Region streams: functional macroprogramming for sensor networks
Authors: Ryan Newton, Matt Welsh
Venue: Proceeedings of the 1st international workshop on Data management for sensor networks: in conjunction with VLDB 2004 (2004)

Sensor networks present a number of novel programming challenges for application developers. Their inherent limitations of computational power, communication bandwidth, and energy demand new approaches to programming that shield the developer from low-level details of resource management, concurrency, and in-network processing. We argue that sensor networks should be programmed at the global level, allowing the compiler to automatically generate nodal behaviors from a high-level specification of the network's global behavior.This paper presents the design of a functional macroprogramming language for sensor networks, called Regiment. The essential data model in Regiment is based on region streams, which represent spatially distributed, time-varying collections of node state. A region stream might represent the set of sensor values across all nodes in an area or the aggregation of sensor values within that area. Regiment is a purely functional language, which gives the compiler considerable leeway in terms of realizing region stream operations across sensor nodes and exploiting redundancy within the network.We describe the initial design and implementation of Regiment, including a compiler that transforms a macroprogram into an efficient nodal program based on a token machine. We present a progresssion of simple programs that illustrate the power of Regiment to succinctly represent robust, adaptive sensor network applications.
Watermark Based Digital Rights Management
Authors: Piyali Mandal, Ashish Thakral, Shekhar Verma
Venue: Proceedings of the International Conference on Information Technology: Coding and Computing (ITCC'05) - Volume I - Volume 01 (2005)

The business of content providers is being threatened by technology advances in hardware, software and IP networks resulting in an increasing amount of illegal copies available online as well as offline. Digital Rights Management standards are being developed for the digital content and Digital Watermarking, a popular technique for content authentication and forgery prevention is viewed as an enabling technology to protect distributed content from unauthorized reuse, or reuse with inadequate credit. This paper establishes the role of an administrative body, by the name of Central Watermarking Body, in sharing the responsibilities of the content providers, in securing the genuine content and in protecting the rights of the customers by allowing them to judge if the content they have paid for, is genuine. The paper also highlights the objectives, technological details, the economic feasibility, the issues pertaining to the practical implementation and the limitations of the Watermark based DRM model.
Computational Modeling of Coupled Dynamic Phase Transformations in Shape Memory Alloys
Authors: D. Roy Mahapatra, R. V. N. Melnik
Venue: Proceedings of the 19th International Symposium on High Performance Computing Systems and Applications (2005)

In spite of several modeling approaches to understand the shape memory alloy (SMA) behaviour, many difficulties exist because of the various limitations of the existing free energy models. Associated phase kinetics coupled with the thermoelstodynamics is still not fully tractable. A new dynamic model of 3D SMA is developed in this paper which employs an improved version of the microscopic Landau theory. Essential properties of the single and multi-variant martensitic phase transformations are recovered using consistent steps, which eliminates the problem of non-uniqueness of energy partitioning and relaxes the oversensitivity of the free energy due to many unknown material constants in previously reported models. The newly developed microscopic model is incorporate in a variationally formulated finite element framework. Newmarkýs time integration scheme is adopted and the condition for consistent iteration to solve the strongly nonlinear system at each time step is highlighted. Banded assembly of the discretized system matrix is performed in parallel. A parallel PCG method with Jacobi preconditioner is employed to solve the system at each time step.