Cheminformatics analysis and learning in a data pipelining environment

Summary Workflow technology is being increasingly applied in discovery information to organize and analyze data. SciTegic's Pipeline Pilot is a chemically intelligent implementation of a workflow technology known as data pipelining. It allows scientists to construct and execute workflows using components that encapsulate many cheminformatics based algorithms. In this paper we review SciTegic's methodology for molecular fingerprints, molecular similarity, molecular clustering, maximal common subgraph search and Bayesian learning. Case studies are described showing the application of these methods to the analysis of discovery data such as chemical series and high throughput screening results. The paper demonstrates that the methods are well suited to a wide variety of tasks such as building and applying predictive models of screening data, identifying molecules for lead optimization and the organization of molecules into families with structural commonality.     

Analysis of the Pressure Gradients According to Capsule Flow Mechanism

This study investigated the experimental coefficient in the mathematical correlation for the pressure gradient of spherical capsule train flow according to flow regimes. The investigation was carried out in the 1.2 × 10⁴ < Re < 1.5 × 10⁵ range and under transport concentration of 5 – 30 %. Deviation between the pressure drops measured by experiment and the mathematical correlation was calculated based on new experimental coefficients. The total pressure gradient in the two‐phase flow of the mixture was distinguished as pressure gradients caused by homogeneous flow and those caused by pressure drops, depending on the rotational movement of the capsules. The experimental findings indicate that at lower concentrations, the losses caused by the rotational movement are low, but the losses caused by the homogeneous flow are high. Losses caused by the rotational movement increase as the concentration increases.     

基于FPGA和DSP实现的实时图像压缩

利用FPGA的并行分布流水特点,选用exilinx公司的50万门级芯片XCV400E,设计并实现CIF格式(352×288象素)图像实时DCT变换.该设计采用乒乓模式,只需设计一个快速算法模块(F×C^T)就解决了C×F×C^T的实现算法.当视频信号通过数字化后逐行输入FPGA,在行、场同步信号和采样时钟的控制下,每输入一组数据(8个),就进行行向量与C^T的矩阵乘运算(F×C^T),并将结果按转置方式保存,每输入一个数进行一次(1×8)×(1×8)矩阵运算,每行进行352×(1×8)×(8×8)次矩阵运算,其中44次(1×8)×(8×8)矩阵运算的结果需要按转置形式(H^T=(F×C^T)^T)存储;当输入下一组8行数据时,对该组数据进行与前述8行数据相同的矩阵运算,而对刚做完(F×C^T)运算的8行相应结果,则按正常顺序取出进行(H^T×C^T)运算,将结果按转置形式(G^T=C×H)输出.从而以实时流水的方式完成C×F×C^T运算.功能仿真、时序仿真和与TMS320C62X系统的成功对接验证了本设计及算法的正确性.     

基于XC2V1000型FPGA的FIR抽取滤波器的设计与实现

介绍XC2V1000型现场可编程门阵列(FPGA)的主要特性和FIR抽取滤波器的工作原理,重点阐述用XC2V1000实现FIR抽取滤波器的方法,并给出仿真波形和设计特点.     

A Practical Parallel Algorithm for All-Pair Shortest Path Based on Pipelining

On the basis of Floyd algorithm with the extended path matrix, a parallel algorithm which resolves all-pair shortest path （APSP） problem on cluster environment is analyzed and designed. Meanwhile, the parallel APSP pipelining algorithm makes full use of overlapping technique between computation and communication. Compared with broadcast operation, the parallel algorithm reduces communication cost. This algorithm has been implemented on MPI on PC-cluster. The theoretical analysis and experimental results show that the parallel algorithm is an efficient and scalable algorithm.     

一种基于椭圆曲线的流水线实现方法

提出了一种基于椭圆曲线的流水线实现方法,来解决串行计算的效率低下问题.通过分析椭圆曲线密码运算的数据相关性,在不增加模乘器面积的前提下,采用三级流水线,提高了椭圆曲线密码的运算速度,并给出适用于椭圆曲线密码VLSI设计的流水线的实现流程.     

A pipelined implementation of the Winograd FFT for satellite on-board multi-carrier demodulation

This paper discusses the implementation of a pipelined architecture for implementing large block size Winograd FFTs. The advantages of using the Winograd over the Cooley-Tukey radix-2 FFT are discussed and some estimates of possible power consumption of a silicon implementation of the architecture are made.     

基于FPGA的浮点FIR滤波器的设计与实现

针对短波宽带接收机系统中信号动态范围大的特点，自定义了24位的浮点格式，并采用流水线技术设计了该格式浮点数的加法和乘法运算单元。在分析了各种FIR滤波器优缺点的基础上．结合FPGA的特点给出了转置型FIR校正滤波器设计方案。最后，以数据率为2．5MS／S的宽带信号为输入，Ahera公司的EP2S60F672C5芯片为硬件平台仿真实现了10通道短波宽带接收机的250阶FIR校正滤波器，最高运行速率达到130MHz以上。     

A parallel version of a fast algorithm for singular integral transforms

The mathematical foundation of an algorithm for fast and accurate evaluation of singular integral transforms was given by Daripa [9,10,12]. By construction, the algorithm offers good parallelization opportunities and a lower computational complexity when compared with methods based on quadrature rules. In this paper we develop a parallel version of the fast algorithm by redefining the inherently sequential recurrences present in the original sequential formulation. The parallel version only utilizes a linear neighbor-to-neighbor communication path, which makes the algorithm very suitable for any distributed memory architecture. Numerical results and theoretical estimates show good parallel scalability of the algorithm. This revised version was published online in June 2006 with corrections to the Cover Date.     

JPEG解码器IP核的设计与实现

介绍了基于静止图像压缩标准JPEG解码器IP核的设计与实现.设计采用适于硬件实现的IDCT算法结构,通过增加运算并行度和流水线技术相结合的方法以提高处理速度.根据Huffman码流特点,采用新的Huffman并行解码硬件实现结构,用简单的算术运算代替复杂的配对模式,解码速度快,硬件成本低.该IP核可方便地集成到诸如数码...