General purpose graphic processing unit （GPU） calculation technology is gradually widely used in various fields. Its mode of single instruction, multiple threads is capable of seismic numerical simulation which has ...General purpose graphic processing unit （GPU） calculation technology is gradually widely used in various fields. Its mode of single instruction, multiple threads is capable of seismic numerical simulation which has a huge quantity of data and calculation steps. In this study, we introduce a GPU-based parallel calculation method of a precise integration method （PIM） for seismic forward modeling. Compared with CPU single-core calculation, GPU parallel calculating perfectly keeps the features of PIM, which has small bandwidth, high accuracy and capability of modeling complex substructures, and GPU calculation brings high computational efficiency, which means that high-performing GPU parallel calculation can make seismic forward modeling closer to real seismic records.展开更多
Information Commons(IC,信息共享中心)是20世纪90年代国外高校图书馆为适应用户需求的变化而建立起来的一种新型的图书馆服务模式。本文阐明了IC兴起的背景及其发展和应用;分析了其构成要素和服务模式;从4个方面探讨了对我国图书馆的...Information Commons(IC,信息共享中心)是20世纪90年代国外高校图书馆为适应用户需求的变化而建立起来的一种新型的图书馆服务模式。本文阐明了IC兴起的背景及其发展和应用;分析了其构成要素和服务模式;从4个方面探讨了对我国图书馆的启示和借鉴作用。展开更多
In the paper, a general framework for large scale modeling of macroeconomic and financial time series is introduced. The proposed approach is characterized by simplicity of implementation, performing well independentl...In the paper, a general framework for large scale modeling of macroeconomic and financial time series is introduced. The proposed approach is characterized by simplicity of implementation, performing well independently of persistence and heteroskedasticity properties, accounting for common deterministic and stochastic factors. Monte Carlo results strongly support the proposed methodology, validating its use also for relatively small cross-sectional and temporal samples.展开更多
The key to large-scale parallel solutions of deterministic particle transport problem is single-node computation performance. Hence, single-node computation is often parallelized on multi-core or many-core computer ar...The key to large-scale parallel solutions of deterministic particle transport problem is single-node computation performance. Hence, single-node computation is often parallelized on multi-core or many-core computer architectures. However, the number of on-chip cores grows quickly with the scale-down of feature size in semiconductor technology. In this paper, we present a scalability investigation of one energy group time-independent deterministic discrete ordinates neutron transport in 3D Cartesian geometry(Sweep3D) on Intel's Many Integrated Core(MIC) architecture, which can provide up to 62 cores with four hardware threads per core now and will own up to 72 in the future. The parallel programming model, Open MP, and vector intrinsic functions are used to exploit thread parallelism and vector parallelism for the discrete ordinates method, respectively. The results on a 57-core MIC coprocessor show that the implementation of Sweep3 D on MIC has good scalability in performance. In addition, the application of the Roofline model to assess the implementation and performance comparison between MIC and Tesla K20 C Graphics Processing Unit(GPU) are also reported.展开更多
Having been excluded from the category of public libraries in China for a long time,the functions and facilities of rural libraries were scattered in diverse cultural projects,thus presenting a separately constructed ...Having been excluded from the category of public libraries in China for a long time,the functions and facilities of rural libraries were scattered in diverse cultural projects,thus presenting a separately constructed and multiply managed situation,in which rural libraries were low in efficiency,weak in professional quality,and difficult to continue their development.It is urgent to promote the construction of integrated platform for services in rural libraries.Pingqiao District in Xinyang has constructed 18 standardized rural libraries in villages and towns in accordance with the concept of public libraries,and tried to integrate the functions of public library previously decentralized in projects of rural public cultural services into these rural libraries,which has led to the initial formation of an integrated platform of services in rural libraries.Although there still exist some dilemmas in the system and the mechanism and difficulties in professional development,the experience suggests that the public library system in rural China will develop in the following directions,that is,led by the developmental concept of advanced culture,adhering to the principles of government leadership and overall urban-rural development,then to construct a regional library network service system,in which municipal libraries are positioned as the core of the system,the libraries at the county level as the center,the libraries in villages,towns and agencies as the sections,the libraries in community streets and farmers’ reading rooms as the branches,and book mobiles as the supplements.展开更多
基金supported by the National Natural Science Foundation of China (Nos 40974066 and 40821062)National Basic Research Program of China (No 2007CB209602)
文摘General purpose graphic processing unit （GPU） calculation technology is gradually widely used in various fields. Its mode of single instruction, multiple threads is capable of seismic numerical simulation which has a huge quantity of data and calculation steps. In this study, we introduce a GPU-based parallel calculation method of a precise integration method （PIM） for seismic forward modeling. Compared with CPU single-core calculation, GPU parallel calculating perfectly keeps the features of PIM, which has small bandwidth, high accuracy and capability of modeling complex substructures, and GPU calculation brings high computational efficiency, which means that high-performing GPU parallel calculation can make seismic forward modeling closer to real seismic records.
文摘In the paper, a general framework for large scale modeling of macroeconomic and financial time series is introduced. The proposed approach is characterized by simplicity of implementation, performing well independently of persistence and heteroskedasticity properties, accounting for common deterministic and stochastic factors. Monte Carlo results strongly support the proposed methodology, validating its use also for relatively small cross-sectional and temporal samples.
基金Supported by National Natural Science Foundation of China(Nos.61402039,61170083,60970033,61373032 and 91430218)National High Technology Research and Development Program of China(No.2012AA01A301)+1 种基金China Postdoctoral Science Foundation(No.2014M562570)National Key Basic Research Program of China(No.61312701001)
文摘The key to large-scale parallel solutions of deterministic particle transport problem is single-node computation performance. Hence, single-node computation is often parallelized on multi-core or many-core computer architectures. However, the number of on-chip cores grows quickly with the scale-down of feature size in semiconductor technology. In this paper, we present a scalability investigation of one energy group time-independent deterministic discrete ordinates neutron transport in 3D Cartesian geometry(Sweep3D) on Intel's Many Integrated Core(MIC) architecture, which can provide up to 62 cores with four hardware threads per core now and will own up to 72 in the future. The parallel programming model, Open MP, and vector intrinsic functions are used to exploit thread parallelism and vector parallelism for the discrete ordinates method, respectively. The results on a 57-core MIC coprocessor show that the implementation of Sweep3 D on MIC has good scalability in performance. In addition, the application of the Roofline model to assess the implementation and performance comparison between MIC and Tesla K20 C Graphics Processing Unit(GPU) are also reported.
文摘Having been excluded from the category of public libraries in China for a long time,the functions and facilities of rural libraries were scattered in diverse cultural projects,thus presenting a separately constructed and multiply managed situation,in which rural libraries were low in efficiency,weak in professional quality,and difficult to continue their development.It is urgent to promote the construction of integrated platform for services in rural libraries.Pingqiao District in Xinyang has constructed 18 standardized rural libraries in villages and towns in accordance with the concept of public libraries,and tried to integrate the functions of public library previously decentralized in projects of rural public cultural services into these rural libraries,which has led to the initial formation of an integrated platform of services in rural libraries.Although there still exist some dilemmas in the system and the mechanism and difficulties in professional development,the experience suggests that the public library system in rural China will develop in the following directions,that is,led by the developmental concept of advanced culture,adhering to the principles of government leadership and overall urban-rural development,then to construct a regional library network service system,in which municipal libraries are positioned as the core of the system,the libraries at the county level as the center,the libraries in villages,towns and agencies as the sections,the libraries in community streets and farmers’ reading rooms as the branches,and book mobiles as the supplements.
