Optimizing convolution operations on GPUs using adaptive tiling

The research domain of Multimedia Content Analysis (MMCA) considers all aspects of the automated extraction of knowledge from multimedia data. High-performance computing techniques are necessary to satisfy the ever increasing computational demands of MMCA applications. The introduction of Graphics Processing Units (GPUs) in modern cluster systems presents application developers with a challenge. While GPUs are well known to be capable of providing significant performance improvements, the programming complexity vastly increases. To this end, we have extended a user transparent parallel programming model for MMCA, named Parallel-Horus, to allow the execution of compute intensive operations on the GPUs present in the cluster. The most important class of operations in the MMCA domain are convolutions, which are typically responsible for a large fraction of the execution time. Existing optimization approaches for CUDA kernels in general as well as those specific to convolution operations are too limited in both performance and flexibility. In this paper, we present a new optimization approach, called adaptive tiling, to implement a highly efficient, yet flexible, library-based convolution operation for modern GPUs. To the best of our knowledge, our implementation is the most optimized and best performing implementation of 2D convolution in the spatial domain available to date.     

DISCWorld: an environment for service-based matacomputing

We describe our DISCWorld system for wide-area, high-performance metacomputing in which we adopt a high-level, service-based approach. Users’ client programs request combinations of services from a set of server nodes which communicate at a peer-based level. DISCWorld is a constrained metacomputing system, running only the service operations its participating resource administrators have chosen to provide and advertise, and provides a common integration environment for clients to access these services and developers to make them available. We discuss our software architecture and experiences building DISCWorld using Java and CORBA components, and the associated research issues for metacomputing that we are addressing.     

Analysis of lipid classes by solid-phase extraction and high-performance size-exclusion chromatography

An improved method to analyze lipid classes of edible oils and fats by solid-phase extraction (SPE) and high-performance size-exclusion chromatography (HPSEC) is presented. A mixture of lipid standards was fractionated by the solid-phase extraction procedure (NH₂ phase) into polar and nonpolar fractions; these were then submitted to analysis by HPSEC. The size-exclusion chromatographic columns were three styrene/divinylbenzene columns with pore sizes of 100 Å and 50 Å. Light-scattering was used for the detection system, and the parameters of the detector were optimized to minimize the difference between the responses of the compounds studied. With this procedure it was possible to separate the following lipid classes: triacylglycerols, diacylglycerols, monoacylglycerols and free fatty acids, sterols, sterol esters, tocopherols and carotenoids. Quantitative analysis was studied for a light-scattering detector with several lipid standards of different molecular weights and unsaturation levels.     

Contingent Behaviours

Michelle Addington questions the accepted Modernist conception of the interior as a hermetically sealed envelope. She highlights the vicissitudes in attitudes that have existed over time to interior and exterior conditions by flagging up the 19th-century pursuit of ventilation and the permeable outside wall, which was pursued in the quest for public sanitation and a misguided belief in the ‘toxic’ interior. Copyright © 2009 John Wiley & Sons, Ltd.     

片式高频噪声滤波组件及其应用（1）

片式高频噪声滤波组件有一个最大的优点,即在小尺寸内可以实现较高的插入损耗。这里有几种不同的滤波组件,如LC滤波器、RC滤波器、π型滤波器、T型滤波器和高性能的滤波组件,等等。在这篇文章里要分两期来讨论它们的结构、性能和应用,这是第一部分。     

日地空间信息分布式协同高性能计算框架

以日地系统活动规律研究为背景,基于美国新近提出的应用于大规模科学计算领域的组件规范CCA（Common Component Architecture）,设计提出了日地空间信息分布式协同高性能计算框架DCHF-SI,它集物理模型组件化封装、模拟应用的构建和管理、模型互操作、分布式容错和计算驾驭可视化等服务于一体,能够充分利用网络集成大量的分布式高性能计算资源和空间物理模型资源来构建多物理松耦合模拟应用,支持日地空间信息的分布式协同高性能计算,解决了多物理耦合模拟的复杂性问题,最终为空间天气预报服务系统提供支持。     

Phytochemical and Antioxidant Profile of Pigmented and Non-Pigmented Rice Cultivars of Arunachal Pradesh,India

This study was carried out to determine the phytochemical and antioxidant properties of two pigmented rice cultivars viz., Lingkang taker ame, Umling ame, and a non-pigmented rice Pungpo taker ame. Fourier transform infrared and high-performance liquid chromatography analysis of phenolic compounds were carried out for the rice cultivars. The highest level of total phenolic, anthocyanin, and scavenging activities were observed in Umling ame cultivar. Fourier transform infrared result of rice cultivars showed wide range of frequency (1131.60–3538.75 cm^–1) which confirmed the presence of various phenolic compounds. Seven phenolic acids were detected in the rice cultivars. The highest value of salicylic acid (302.06 ± 0.01 mg/L), ferulic acid (17.21 ± 0.02 mg/L), apigenin (7.03 ± 0.01 mg/L), and gallic acid (0.98 ± 0.04 mg/L) were detected in Umling ame; whereas the highest value of quercetin (611.46 ± 0.01 mg/L) and caffeic acid (1.83 ± 0.01 mg/L) were found in Pungpo taker ame and Lingkang taker ame cultivars, respectively. Results revealed that the colored rice Umling ame showed higher phenolic content than other two rice cultivars Lingkang taker ame and Pungpo taker ame.     

3500中厚板热矫直机在线改造

详细分析了某钢厂3500中厚板老式热矫直机各主要结构和性能,分析了影响原设备矫直能力的各个薄弱环节,针对性提出了升级改造的设计方案,改造效果显著,可为同类设备提供借鉴。     

浅谈地铁防水高性能混凝土配合比设计

本文结合在建福州地铁1号线白湖亭站工程实际,浅谈地铁防水高性能混凝土配合比优化设计。     

Development and validation of an HPLC-based screening method to acquire polyhydroxyalkanoate synthase mutants with altered substrate specificity

A rapid and convenient method for the compositional analysis of polyhydroxyalkanoate (PHA) was developed using high-performance liquid chromatography (HPLC) and alkaline sample pretreatment in a 96-well plate format. The reliability of this system was confirmed by the fact that a mutant with a D171G mutation of Aeromonas caviae PHA synthase (PhaC(Ac)), which gained higher reactivity toward 3-hydroxyhexanoate (3HHx), was selected from the D171X mutant library. Together with D171G mutant, several single mutants showing high reactivity toward 3HHx were isolated by the HPLC assay. These new mutants and double mutants combined with an N149S mutation were used to synthesize P(3-hydroxybutyrate-co-3HHx) in Ralstonia eutropha PHB(-)4 from soybean oil as carbon source, achieving higher levels of 3HHx fraction than the wild-type enzyme. Based on these results, the high-throughput screening system will serve as a powerful tool for exploring new and beneficial mutations responsible for regulating copolymer composition of PHA.