1921065
Partitioning loops with variable dependence distances
A new technique to parallelize loops with variable distance vectors is presented. The method extends previous methods in two ways. First, the present method makes it possible for array subscripts to be any linear combination of all loop indices. The solutions to the linear dependence equations established from such array subscripts are characterized by a pseudo distance matrix (PDM). Second, it allows us to exploit loop parallelism from the PDM by applying unimodular and partitioning transformations that preserve the lexicographical order of the dependent iterations. The algorithms to derive the PDM, to find a suitable loop transformation and to generate parallel code are described, showing that it is possible to parallelize a wider range of loops automatically.
31072695
Making XML document markup international
In name and in practice, the World-Wide Web (hereafter Web) is used around the World beyond English-speaking areas. This creates a tremendous need to internationalize standard terminology used in the technologies that make the Web possible. Existing efforts on XML internationalization (i18n) and localization (i10n) have focused on the content of XML documents instead of the terms used in markup (annotations) such as elements and attributes. The SGML standard ISO 8879 supports the use of Unicode (ISO 10646) throughout a document, including markups. However, most elements and attributes of XML documents are still defined in English, thereby limiting their use among non-English speakers. This paper presents an XSLT-based method that can completely localize the markup of XML documents into different natural languages. We also describe how the proposed technique can be applied to translation problems in programming (e.g. C and Java) or documentation (e.g. LATEX or other formatting languages) so that a program or a document can be converted to and from an XML format.
4001661
Configuring common personal software: a requirements-driven approach
We investigate the personalization capabilities of common personal software systems. We use a typical e-mail client as an example of such a system, and examine the configuration screens it offers to its users. We discover that each configuration value reflects each of the ways with which the user goals can be satisfied. Thus, we construct a goal model in which alternative ways for satisfying high level goals are matched with alternative system configurations. This way, automatic configuration of the system by reasoning about the overlaying goal model can be achieved. We find that the vast majority of the configuration options that refer to system functionality can be configured using this method, facilitating thereby the personalization tasks for users with no technical background, and ensuring, at the same time, consistency and meaningfulness in the configuration result.
7902088
Performance visualizations using XML representations
The intermediate representation (IR) forms the information exchanged among different passes of program compilation. The intermediate format proposed for extensibility and persistence is written in XML. In this way, the program transformations that were internal to the compiler become visible. The hierarchical structure of XML makes a natural representation for the abstract syntax tree (AST). A compiler can parse the program source into an IR, then output it as an XML document. Separated by orthogonal namespaces, other IRs are also presented in the same XML document, gathering program information such as dependence vectors, transforming matrices, iteration spaces dependence graphs and cache reuse distances. This XML document can be exchanged between the compiler and program visualizers for parallelism and locality.
11134282
Visualizing the impact of the cache on program execution
The global cache misses ratio of a program does not reveal the time distribution of the memory reference patterns in detail. On the other hand, cache visualization is hampered by the huge amount of memory references to display. Therefore, many visualizers focus on a snapshot of the cache content, instead of viewing all memory transactions. A cache visualizer is introduced which presents the integral cache behavior of a program in several complementary views: the density view of the cache misses shows the hot spots of the program; the reuse distances view shows the data locality and its effect on performance; the histogram view shows the periodical patterns that occurs in the trace. In a number of experiments, the visualizer has been used to characterize the cache behavior and effectively improve the cache behavior and program performance.
11507388
JPT: A Java Parallelization Tool
PVM is a succesfull programming environment for distributed computing in the languages C and Fortran. Recently several implementations of PVM for Java have been added, making PVM programming accessible to the Java community. 
 
With PVM for Java however, the user still needs to partition the problem, calculate the data partitioning and program the message passing and synchronization. In this paper, JPT is introduced, a parallelization tool which generates PVM code from a serial Java program. JPT automatically detects parallel loops and generates master and slave PVM programs.
40955801
Polarimetric SAR image segmentation using texture partitioning and statistical analysis
This paper presents a new technique for partitioning polarimetric synthetic aperture radar (POL-SAR) imagery into regions of homogeneous polarimetric backscattering properties. The method consists of two cascaded steps: an initial texture segmentation of one image derived from the POL-SAR data, and a polarimetric statistical region merging process that refines and modifies the initial segmentation. In the first stage, a morphological region-based image partitioning technique, the watershed algorithm, plays the key role. While in the second stage, the region adjacency graph and the segment dissimilarity measures derived from the Wishart model and the K distribution are applied. The overall segmentation algorithm has been tested using real 4-look POL-SAR imagery and sample results are provided in the paper. The main innovation of this work is the utilization of the K distribution in the segmentation process.
2412157
Optimal adaptive bandwidth monitoring for QoS based retrieval
Network aware multimedia delivery applications are a class of applications that provide certain level of quality of service (QoS) guarantees to end users while not assuming underlying network resource reservations. These applications guarantee QoS parameters like media object transmission time limit by actively monitoring the available bandwidth of the network and adapting the object to a target size that can be transmitted within a given time limit. A critical problem is how to obtain an accurate enough estimation of available bandwidth while not wasting too much time in bandwidth testing. In this paper, we present an algorithm to determine optimal amount of bandwidth testing given a probabilistic confidence level for network-aware multimedia object retrieval applications. The model treats the bandwidth testing as sampling from an actual bandwidth population. It uses statistical estimation method to quantify the benefit of each new bandwidth-testing sample, which is used to determine the optimal amount of bandwidth testing by balancing the benefit with the cost of each sample. Our implementation and experiments shows the algorithm determines the optimal amount of bandwidth testing effectively with minimum computation overhead.
123116880
Shadow Graphs and 3D Texture Reconstruction
We present methods for recovering surface height fields such as geometric details of 3D textures by incorporating shadow constraints. We introduce shadow graphs which give a new graph-based representation for shadow constraints. It can be shown that the shadow graph alone is sufficient to solve the shape-from-shadow problem from a dense set of images. Shadow graphs provide a simpler and more systematic approach to represent and integrate shadow constraints from multiple images. To recover height fields from a sparse set of images, we propose a method for integrated shadow and shading constraints. Previous shape-from-shadow algorithms do not consider shading constraints while shape-from-shading usually assumes there is no shadow. Our method is based on collecting a set of images from a fixed viewpoint as a known light source changes its position. It first builds a shadow graph from shadow constraints from which an upper bound for each pixel can be derived if the height values of a small number of pixels are initialized correctly. Finally, a constrained optimization procedure is designed to make the results from shape-from-shading consistent with the height bounds derived from the shadow constraints. Our technique is demonstrated on both synthetic and real imagery.
14491026
An iterative method for optimizing FIR filters synthesized using the two-stage frequency-response masking technique
An efficient technique for drastically reducing the number of multipliers and adders in narrow-transition band linear-phase finite-impulse response filters is to use one-stage or multistage frequency-response masking (FRM) approaches as originally introduced by Lim. It has been observed recently that for the one-stage FRM approach the filter complexity can be considerably reduced by iteratively optimizing the periodic filter and masking filters by properly sharing the frequency-response-shaping responsibilities in their respective frequency regions. In this paper, a similar iterative method is applied to the two-stage FRM structure to reduce the filter complexity even more. An example taken from the literature is included illustrating that the number of adders and multipliers for the resulting filters are less than 75 percent compared with the original designs.
5420099
A new approach to estimating the expected first hitting time of evolutionary algorithms
The expected first hitting time is an important issue in theoretical analyses of evolutionary algorithms since it implies the average computational time complexity. In this paper, by exploiting the relationship between the convergence rate and the expected first hitting time, a new approach to estimating the expected first hitting time is proposed. This approach is then applied to four evolutionary algorithms which involve operators of mutation, mutation with population, mutation with recombination, and time-variant mutation, respectively. The results show that the proposed approach is helpful for analyzing a broad range of evolutionary algorithms.