New two-dimensional fuzzy C-means clustering algorithm for image segmentation

To solve the problem of poor anti-noise performance of the traditional fuzzy C-means (FCM) algorithm in image segmentation, a novel two-dimensional FCM clustering algorithm for image segmentation was proposed. In this method, the image segmentation was converted into an optimization problem. The fitness function containing neighbor information was set up based on the gray information and the neighbor relations between the pixels described by the improved two-dimensional histogram. By making use of the global searching ability of the predator-prey particle swarm optimization, the optimal cluster center could be obtained by iterative optimization, and the image segmentation could be accomplished. The simulation results show that the segmentation accuracy ratio of the proposed method is above 99%. The proposed algorithm has strong anti-noise capability, high clustering accuracy and good segment effect, indicating that it is an effective algorithm for image segmentation.

Spatial distribution patterns of anorectal atresia/stenosis in China:Use of two-dimensional graph-theoretical clustering

AIM:To investigate the spatial distribution patterns of anorectal atresia/stenosis in China.METHODS:Data were collected from the Chinese Birth Defects Monitoring Network(CBDMN),a hospital-based congenital malformations registry system.All fetuses more than 28 wk of gestation and neonates up to 7 d of age in hospitals within the monitoring sites of the CBDMN were monitored from 2001 to 2005.Two-dimensional graph-theoretical clustering was used to divide monitoring sites of the CBDMN into different clusters according to the average incidences of anorectal atresia/stenosis in the different monitoring sites.RESULTS:The overall average incidence of anorectal atresia/stenosis in China was 3.17 per 10000 from 2001 to 2005.The areas with the highest average incidences of anorectal atresia/stenosis were almost always focused in Eastern China.The monitoring sites were grouped into 6 clusters of areas.Cluster 1 comprised the monitoring sites in Heilongjiang Province,Jilin Province,and Liaoning Province;Cluster 2 was composed of those in Fujian Province,Guangdong Province,Hainan Province,Guangxi Zhuang Autonomous Region,south Hunan Province,and south Jiangxi Province;Cluster 3 consisted of those in Beijing Municipal City,Tianjin Municipal City,Hebei Province,Shandong Province,north Jiangsu Province,and north Anhui Province;Cluster 4 was made up of those in Zhejiang Province,Shanghai Municipal City,south Anhui Province,south Jiangsu Province,north Hunan Province,north Jiangxi Province,Hubei Province,Henan Province,Shanxi Province and Inner Mongolia Autonomous Region;Cluster 5 consisted of those in Ningxia Hui Autonomous Region,Gansu Province and Qinghai Province;and Cluster 6 included those in Shaanxi Province,Sichuan Province,Chongqing Municipal City,Yunnan Province,Guizhou Province,Xinjiang Uygur Autonomous Province and Tibet Autonomous Region.CONCLUSION:The fi ndings in this research allow the display of the spatial distribution patterns of anorectal atresia/stenosis in China.These will have important guiding significance for further analysis of relevant environmental factors regarding anorectal atresia/ stenosis and for achieving regional monitoring for anorectal atresia/stenosis.

DPGL:The Direct3D9-based Parallel Graphics Library for Multi-display Environment

The emergence of high performance 3D graphics cards has opened the way to PC clusters for high performance multi- display environment. In order to exploit the rendering ability of PC clusters, we should design appropriate parallel rendering algorithms and parallel graphics library interfaces. Due to the rapid development of Direct3D, we bring forward DPGL, the Direct3D9-based parallel graphics library in D3DPR parallel rendering system, which implements Direct3D9 interfaces to support existing Direct3D9 application parallelization with no modification. Based on the parallelism analysis of Direct3D9 rendering pipeline, we briefly introduce D3DPR parallel rendering system. DPGL is the fundamental component of D3DPR. After presenting DPGL three layers architecture, we discuss the rendering resource interception and management. Finally, we describe the design and implementation of DPGL in detail, including rendering command interception layer, rendering command interpretation layer and rendering resource parallelization layer.

Multi-relaxation-time lattice Boltzmann simulations of lid driven flows using graphics processing unit

Large eddy simulation （LES） using the Smagorinsky eddy viscosity model is added to the two-dimensional nine velocity components （D2Q9） lattice Boltzmann equation （LBE） with multi-relaxation-time （MRT） to simulate incompressible turbulent cavity flows with the Reynolds numbers up to 1 × 10^7. To improve the computation efficiency of LBM on the numerical simulations of turbulent flows, the massively parallel computing power from a graphic processing unit （GPU） with a computing unified device architecture （CUDA） is introduced into the MRT-LBE-LES model. The model performs well, compared with the results from others, with an increase of 76 times in computation efficiency. It appears that the higher the Reynolds numbers is, the smaller the Smagorinsky constant should be, if the lattice number is fixed. Also, for a selected high Reynolds number and a selected proper Smagorinsky constant, there is a minimum requirement for the lattice number so that the Smagorinsky eddy viscosity will not be excessively large.

Cluster Analysis on the Nucleotide Sequences of Six Genes in Rice

[ Objective] This study aimed to construct four-dimensional graphics of nucleotide sequences of six genes in rice （ GluB-6, GtuB-7, PDIL2, OsMPK1, OsCATC, OsCATA） and to conduct phase-space clustering, thus demonstrating the relationship between the structure and function of rice genes. [ Method ] Base sequences were represented by four-dimensional graphics and clustered in the phase space. The relationship between clustering results and biological characteristics of these genes were analyzed. [ Result] Genes with similar four-dimensional graphics exhibit similar biological characteristics. [ Conclusion] Four-dimensional graphics of genes with different functions and base lengths present phase-space relationship with their biological functions, which provided an effective way for the prediction of gene function.

Synthesis and Spectroscopic Study of a New Li-B-V-O Cluster Compound

In this paper,the synthesis of a novel polyoxovanadiumborate[Li(H2O)3]3[V12B18O48(OH)12(OH)]·(H2O)5by hydrothermal method.FTIR,2DFTIR and UV-Vis absorption spectroscopy were employed to explore the relationships between structure and properties of 3-D compound 1.

Real-time color holographic video reconstruction using multiple-graphics processing unit cluster acceleration and three spatial light modulators

We demonstrate real-time three-dimensional(3D)color video using a color electroholographic system with a cluster of multiple-graphics processing units(multi-GPU)and three spatial light modulators(SLMs)corresponding respectively to red,green,and blue(RGB)-colored reconstructing lights.The multi-GPU cluster has a computer-generated hologram(CGH)display node containing a GPU,for displaying calculated CGHs on SLMs,and four CGH calculation nodes using 12 GPUs.The GPUs in the CGH calculation node generate CGHs corresponding to RGB reconstructing lights in a 3D color video using pipeline processing.Real-time color electroholography was realized for a 3D color object comprising approximately 21,000 points per color.

Real-time electroholography using a single spatial light modulator and a cluster of graphics-processing units connected by a gigabit Ethernet network

Systems containing multiple graphics-processing-unit(GPU)clusters are difficult to use for real-time electroholography when using only a single spatial light modulator because the transfer of the computer-generated hologram data between the GPUs is bottlenecked.To overcome this bottleneck,we propose a rapid GPU packing scheme that significantly reduces the volume of the required data transfer.The proposed method uses a multi-GPU cluster system connected with a cost-effective gigabit Ethernet network.In tests,we achieved real-time electroholography of a three-dimensional(3D)video presenting a point-cloud 3D object made up of approximately 200,000 points.

Efficient parallel implementation of a density peaks clustering algorithm on graphics processing unit

The density peak （DP） algorithm has been widely used in scientific research due to its novel and effective peak density-based clustering approach. However, the DP algorithm uses each pair of data points several times when determining cluster centers, yielding high computational complexity. In this paper, we focus on accelerating the time-consuming density peaks algorithm with a graphics processing unit （GPU）. We analyze the principle of the algorithm to locate its computational bottlenecks, and evaluate its potential for parallelism. In light of our analysis, we propose an efficient parallel DP algorithm targeting on a GPU architecture and implement this parallel method with compute unified device architecture （CUDA）, called the ‘CUDA-DP platform＇. Specifically, we use shared memory to improve data locality, which reduces the amount of global memory access. To exploit the coalescing accessing mechanism of CPU, we convert the data structure of the CUDA-DP program from array of structures to structure of arrays. In addition, we introduce a binary search-and-sampling method to avoid sorting a large array. The results of the experiment show that CUDA-DP can achieve a 45-fold acceleration when compared to the central processing unit based density peaks implementation.

低碳视角下东北三省耕地利用生态效率及分区研究

【目的】低碳视角下耕地利用生态效率及分区研究,对于区域耕地低碳利用和用地结构调整具有重要意义,是形成耕地数量、质量及生态“三位一体”保护格局,推进耕地生态文明建设的重要举措。【方法】构建低碳视角下耕地利用生态效率指标体系,借助超效率SBM模型(Super slacks-based measure)和ArcGIS软件揭示研究区耕地利用生态效率时空分异特征,并运用两维图论聚类法进行耕地利用生态分区,提出各分区方向。【结果】①2010—2020年研究区耕地利用生态效率呈波动下降趋势,核密度波峰呈“双峰—单峰—双峰”的分布特征,主峰由“宽峰”转变为“尖峰”,两极分化特征明显,地区差异逐渐缓解;②低效率型波峰由“双峰”向“单峰”转变,生态效率极化现象趋于好转;中效率型波峰为“一主一小”的双峰形态,生态效率呈现两极分化的区域聚集现象;高效率型主峰高度降低,生态效率内部差异逐步减小;③耕地利用生态效率存在集聚效应,形成北高南低的空间分布格局,热点区向南扩展,冷点区围绕西南部移动,呈“收缩—扩大—收缩”趋势。④将耕地利用划分为耕地利用生态先导区、均衡区、互补区和升级区4个区,制定区域差异化的耕地低碳利用措施。【结论】研究结果有利于东北三省耕地低碳利用和优化用地布局,以期为实现耕地可持续利用,推进耕地生态文明建设提供一定理论参考。

Real-time spatiotemporal division multiplexing electroholography for 1,200,000 object points using multiple-graphics processing unit cluster

Computationally, the calculation of computer-generated holograms is extremely expensive, and the image quality deteriorates when reconstructing three-dimensional(3 D) holographic video from a point-cloud model comprising a huge number of object points. To solve these problems, we implement herein a spatiotemporal division multiplexing method on a cluster system with 13 GPUs connected by a gigabit Ethernet network.A performance evaluation indicates that the proposed method can realize a real-time holographic video of a3 D object comprising ~1,200,000 object points. These results demonstrate a clear 3 D holographic video at32.7 frames per second reconstructed from a 3 D object comprising 1,064,462 object points.

基于数字报历史优秀版面的样式智能生成与微调

在传统报纸印刷行业中,设计人员需要根据设计规则进行人工排版,其排版过程造价成本较高且耗时耗力。为提高排版效率,研究提出一种基于历史优秀版面的样式自动生成与微调方法。为了从数据中学习到报纸排版的风格,创建一个包含丰富的设计元素参数信息的电子报数据库,这些特征信息能够有效地反映报纸的布局。对于给定的新闻文章,首先根据历史优秀版面训练概率模型来推断电子报版面的样式,并结合固定约束和用户约束保证样式有效,同时构建美学设计原理的量化方法进一步实现样式微调。最后通过定性和定量评估,表明新方法可以生成满足视觉美观性、层次性和可读性的报纸。本文方法可为版面设计样式智能生成提供参考。

全媒体交互式演播室集群设计与实践

为节约成本,丽水市广播电视台在实施演播室高清化改造过程中,基于资源共享和集中控制管理理念,将6个独立的演播室改造建设为一个演播室集群,引入先进的图文系统丰富节目创作形态,融合新媒体内容,打造全媒体交互式演播室集群。文章重点介绍该演播室的设计与建设情况。

土地整理优先度评价方法及其应用研究

将主成分分析与两维图论聚类分析有机结合,确立了土地整理优先度的评价方法,并将其应用于宁波市鄞州区土地整理的评价工作中,取得了良好的实际效果.

分层Dirichlet过程及其应用综述

Dirichlet过程是一种应用于非参数贝叶斯模型中的随机过程,特别是作为先验分布应用在概率图模型中.与传统的参数模型相比,Dirichlet过程的应用更加广泛且模型更加灵活,特别是应用于聚类问题时,该过程能够自动确定聚类数目和生成聚类中心的分布参数.因此,近年来,在理论和应用上均得到了迅速的发展,引起越来越多的关注.本文首先介绍Dirichlet过程,而后描述了以Dirichlet过程为先验分布的Dirichlet过程混合模型及其应用,接着概述分层Dirichlet过程及其在相关算法构造中的应用,最后对分层Dirichlet过程的理论和应用进行了总结,并对未来的发展方向作了探讨.

基于图形处理器的数据流快速聚类

在数据流环境下,聚类算法不仅需要有较高的聚类质量,同时需要有实时处理速度.因而,提出了一类基于图形处理器(graphics processing unit,简称GPU)的快速聚类方法,包括基于K-means的基本聚类方法、基于GPU的数据流聚类以及数据流簇进化分析方法.这些方法的共同特点是充分利用了GPU强大的处理能力和流水线特性.与以往具有独立框架的数据流聚类算法不同,这些基于GPU的聚类算法具有同一框架和多种聚类分析功能,为数据流聚类分析提供了统一的平台.从分析可知,数据流聚类分析的核心操作实际上就是距离计算和比较.基于这一认识,利用GPU的子素向量处理功能进行距离计算.性能验证实验是在配有Pentium IV3.4G CPU和NVIDIA GeForce 6800 GT显卡的PC上进行的.综合分析和实验结果表明,基于GPU的数据流聚类算法比传统的CPU算法平均快7倍,从而为高速数据流应用提供了良好的支持.

原子团簇P_8的同分异构体预测

根据由激光产生的磷原子团簇正离子的质谱图所出现具有规律"奇幻数"的线索，即从开始质谱图的信号强度以8为周期变化，可以推断出从开始稳定的磷原子团簇正离子是以P8为结构单元依次聚合而生成的。使用分子图形软件设计出19种P8的同分异构体，并进行分子力学、PM3半经验量子化学和ADF密度泛函优化．所有的模型中的磷原子均采用二配位和三配位成键．从各异构体成键能量的比较中可得知，笼状结构比平面结构稳定，平面环越大越不稳定，最稳定的P8构型是由12个单键组成的楔状结构．虽然目前还没有P8的实验数据，但在某些单质磷和含磷化合物中含有P8楔状结构单元．楔状结构的P8可认为是由2个很稳定正四面体P4分别断裂4个键后重新生成4个键而产生的．

基于数据挖掘的海上交通流数据特征分析

将基于数据挖掘的聚类分析和图形化属性分析方法引入海上交通流数据特性分析领域。阐述了数据挖掘的基本思想与方法,并着重介绍了使用开源数据挖掘工具WEKA对某海上航道的交通流数据进行的数据挖掘实验。实验综合使用聚类分析和图形化属性分析两种方法得到该航道的特性信息,其结果证明利用数据挖掘方法可得到有价值的交通特性信息,并能为海上交通的有效管理提供有力的决策依据。

图形处理器通用计算关键技术研究综述

当前图形处理器的通用计算取得长足发展,为适应通用计算图形处理器在硬件体系结构和软件支持方面完成相应调整和改变,面对各种应用领域中数据规模增大的趋势,多GPU系统和GPU集群的研究应用日趋增多.以流处理器及图形处理器硬件体系为依据,介绍学术和工业领域中流处理器及图形处理器体系变化趋势.从软件编程环境、硬件计算与通信等方面展开讨论,阐述通用计算中图形处理器的关键问题,包括编程模型及语言的发展和方向,存储模型的量化研究、访存模式和行为的优化以及分布式存储管理的热点问题,典型通信原型系统的对比及通信难点的分析,GPU片内和片间的负载均衡,可靠性和容错计算,GPU功耗评测及低功耗优化的研究进展.综述在海量数据处理、智能计算、复杂网络、集群应用领域中图形处理器的研究进展及成果.总结在通用计算发展中存在的技术问题和未来挑战.

HPLC/ELSD指纹图谱和星座图聚类法在清开灵注射液质量评价中的应用

目的对清开灵注射液的质量进行科学评价,为有效控制中药质量提供一种可靠方法。方法采用HPLC/ELSD指纹图谱技术结合星座图聚类法,测定不同厂家的18个批次清开灵注射液的指纹图谱,并评价产品质量。结果本法直观、准确地表达了产品的质量信息。结论本法是中药质量评价的一种直观、合理、有效的技术手段。