对于海量实时数据而言,基于Flink on YARN平台可以对这些数据进行并行化处理。在接下来的工作机制和相关技术中,重点分析了基于此平台典型的流架构的数据传输模式,在此基础上,比对了流处理系统和批处理系统的差异点。对于不同数据处理系...对于海量实时数据而言,基于Flink on YARN平台可以对这些数据进行并行化处理。在接下来的工作机制和相关技术中,重点分析了基于此平台典型的流架构的数据传输模式,在此基础上,比对了流处理系统和批处理系统的差异点。对于不同数据处理系统,分析总结了Flink所面临的一些挑战,希望以此为Flink的进一步研究提供参考。展开更多
This paper investigates the main scale analysis of the aerodynamic noise in the foremost bogie area by the large-eddy simulation(LES)and the Ffowcs Williams-Hawkings(FW-H)analogy.The mechanism of the aerodynamic noise...This paper investigates the main scale analysis of the aerodynamic noise in the foremost bogie area by the large-eddy simulation(LES)and the Ffowcs Williams-Hawkings(FW-H)analogy.The mechanism of the aerodynamic noise in this area has been excavated.The aerodynamic excitation results show that the bogie divides the bogie compartment into two cavities,each of which contains a large circulating flow and presents multi-peak characteristics in the frequency domain.The far-field noise results suggest that in the speed range of 200−350 km/h,the aerodynamic noise mechanism in the bogie area is the same.Cavity noise is the main noise mechanism in the foremost bogie area,and the bogie divides the bogie cabin into two cavities,thereby changing the aerodynamic noise in this area.展开更多
A graphics processing unit(GPU)-accelerated discontinuous Galerkin(DG)method is presented for solving two-dimensional laminar flows.The DG method is ported from central processing unit to GPU in a way of achieving GPU...A graphics processing unit(GPU)-accelerated discontinuous Galerkin(DG)method is presented for solving two-dimensional laminar flows.The DG method is ported from central processing unit to GPU in a way of achieving GPU speedup through programming under the compute unified device architecture(CUDA)model.The CUDA kernel subroutines are designed to meet with the requirement of high order computing of DG method.The corresponding data structures are constructed in component-wised manners and the thread hierarchy is manipulated in cell-wised or edge-wised manners associated with related integrals involved in solving laminar Navier-Stokes equations,in which the inviscid and viscous flux terms are computed by the local lax-Friedrichs scheme and the second scheme of Bassi&Rebay,respectively.A strong stability preserving Runge-Kutta scheme is then used for time marching of numerical solutions.The resulting GPU-accelerated DG method is first validated by the traditional Couette flow problems with different mesh sizes associated with different orders of approximation,which shows that the orders of convergence,as expected,can be achieved.The numerical simulations of the typical flows over a circular cylinder or a NACA 0012 airfoil are then carried out,and the results are further compared with the analytical solutions or available experimental and numerical values reported in the literature,as well as with a performance analysis of the developed code in terms of GPU speedups.This shows that the costs of computing time of the presented test cases are significantly reduced without losing accuracy,while impressive speedups up to 69.7 times are achieved by the present method in comparison to its CPU counterpart.展开更多
The available data on tidal currents spanning periods greater than six months for the continental shelf of the East China Sea (26°30.052′N, 122°35.998′E) were analyzed using several methods. Tidal Current ...The available data on tidal currents spanning periods greater than six months for the continental shelf of the East China Sea (26°30.052′N, 122°35.998′E) were analyzed using several methods. Tidal Current Harmonic Analysis results demonstrated that semi-diurnal tides dominated the current movement. The tidal currents of the principal diurnal and semidiurnal rotated clockwise with depth, with the deflection of the major semi-axes to the right in the upper layer and to the left in the lower layer. The vertical structures of two principal semi-diurnal constituents-M2 and S2-were similar, which indicates that the tidal currents are mainly barotropic in this area. The main features of the variation of the four principal tidal constituents with depth demonstrate that the currents in this region are influenced by the upper and lower boundary layers. Therefore, the tidal constituents of the shallow water are similar. Different vertical modes were calculated based on the Empirical Orthogonal Function (EOF) analysis of the Eastern and Northern components of the tidal currents, with a variance contribution for the zero-order model of at least 90%. The variance contribution of the baroclinic model is minimal, which further reveals a strong barotropic character for the tidal currents of this region.展开更多
Service-oriented business process generation is a key activity in the ServiceOriented Architecture(SOA)business lifecycle,and most of the other activities such as application execution depend on the business process b...Service-oriented business process generation is a key activity in the ServiceOriented Architecture(SOA)business lifecycle,and most of the other activities such as application execution depend on the business process being developed.After the business requirements are acquired,a developer has to use specific programming technologies to orchestrate web services to generate a deployable business process.It is time-consuming to specify all the business processes from lowlevel web services,especially for an enterprise that focuses on a series of similar businesses.This paper proposes a rapid service-oriented business process generation method with domain-specific assets specified in ontology systems.Assets with different levels of granularity are reused to refine the high level business process framework for executable business processes using the Business Process Executional Language(BPEL).The new methodology significantly simplifies service-oriented business process generation by reusing assets to construct business processes.A business process generation tool is also implemented to support the efficient visual design of SOA processes with the proposed method.This paper verifies the proposed method using a shipment tracking case.The studies show that the number of reusable assets increases significantly as these projects progress,and the business process generation speed also increases at the same time.展开更多
Inclination of capital groups--which realize widening impact field of media-to media sector due to relationships based on interests, and relationships/dilemmata between the governing parties and the capital owners hav...Inclination of capital groups--which realize widening impact field of media-to media sector due to relationships based on interests, and relationships/dilemmata between the governing parties and the capital owners have paved the way for a unilateral media structure not hearing the voice of others/local people. It is seen that the main stream media becomes more and more under direction of capital groups. Because of the effects created by the Second World War II, also war and media relation has gain different dimensions. Together with this differentiation, a new notion was born in the field of journalism during occupation period of the lraq by the USA--Embedded Journalism This notion, called as ＂embedded journalism＂ in English can be translated as ＂yapismislik--attachment＂, ＂gomulmusluk---embeddedness＂, and ＂yamanmis-patched＂ in Turkish. In this connection, developments which have also been realized in the media economics in line with globalization process as seen all other aspects of life, changing of ownership structure in the media, and increase of concentrations, monopolization will be scrutinized in our study in addition how the fact of embedded journalism has affected the most important mission of journalism, objectivity within the framework of relations between journalism and government.展开更多
Through analysis of cloud computing and characteristics, the paper described cloud computing infrastructure architecture. Mainly discusses cloud computing advantages in the use of the library and the use should pay at...Through analysis of cloud computing and characteristics, the paper described cloud computing infrastructure architecture. Mainly discusses cloud computing advantages in the use of the library and the use should pay attention to the problem, on this basis, we propose a cloud- based library information platform construction model to analyze the basic architecture of cloud computing, cloud-depth study calculated at the library information platform and database access patterns operating mode, and cloud computing future development and application prospects.展开更多
文摘对于海量实时数据而言,基于Flink on YARN平台可以对这些数据进行并行化处理。在接下来的工作机制和相关技术中,重点分析了基于此平台典型的流架构的数据传输模式,在此基础上,比对了流处理系统和批处理系统的差异点。对于不同数据处理系统,分析总结了Flink所面临的一些挑战,希望以此为Flink的进一步研究提供参考。
基金Project(2017YFB1201103)supported by the National Key Research and Development Plan of ChinaProject(2019zzts540)supported by the Graduate Student Independent Innovation Project of Central South University,China。
文摘This paper investigates the main scale analysis of the aerodynamic noise in the foremost bogie area by the large-eddy simulation(LES)and the Ffowcs Williams-Hawkings(FW-H)analogy.The mechanism of the aerodynamic noise in this area has been excavated.The aerodynamic excitation results show that the bogie divides the bogie compartment into two cavities,each of which contains a large circulating flow and presents multi-peak characteristics in the frequency domain.The far-field noise results suggest that in the speed range of 200−350 km/h,the aerodynamic noise mechanism in the bogie area is the same.Cavity noise is the main noise mechanism in the foremost bogie area,and the bogie divides the bogie cabin into two cavities,thereby changing the aerodynamic noise in this area.
基金partially supported by the National Natural Science Foundation of China(No.11972189)the Natural Science Foundation of Jiangsu Province(No.BK20190391)+1 种基金the Natural Science Foundation of Anhui Province(No.1908085QF260)the Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘A graphics processing unit(GPU)-accelerated discontinuous Galerkin(DG)method is presented for solving two-dimensional laminar flows.The DG method is ported from central processing unit to GPU in a way of achieving GPU speedup through programming under the compute unified device architecture(CUDA)model.The CUDA kernel subroutines are designed to meet with the requirement of high order computing of DG method.The corresponding data structures are constructed in component-wised manners and the thread hierarchy is manipulated in cell-wised or edge-wised manners associated with related integrals involved in solving laminar Navier-Stokes equations,in which the inviscid and viscous flux terms are computed by the local lax-Friedrichs scheme and the second scheme of Bassi&Rebay,respectively.A strong stability preserving Runge-Kutta scheme is then used for time marching of numerical solutions.The resulting GPU-accelerated DG method is first validated by the traditional Couette flow problems with different mesh sizes associated with different orders of approximation,which shows that the orders of convergence,as expected,can be achieved.The numerical simulations of the typical flows over a circular cylinder or a NACA 0012 airfoil are then carried out,and the results are further compared with the analytical solutions or available experimental and numerical values reported in the literature,as well as with a performance analysis of the developed code in terms of GPU speedups.This shows that the costs of computing time of the presented test cases are significantly reduced without losing accuracy,while impressive speedups up to 69.7 times are achieved by the present method in comparison to its CPU counterpart.
基金supported by the National Basic Research Program of China (2007CB411807)the National Natural Science Foundation of China (40806072,41176009)
文摘The available data on tidal currents spanning periods greater than six months for the continental shelf of the East China Sea (26°30.052′N, 122°35.998′E) were analyzed using several methods. Tidal Current Harmonic Analysis results demonstrated that semi-diurnal tides dominated the current movement. The tidal currents of the principal diurnal and semidiurnal rotated clockwise with depth, with the deflection of the major semi-axes to the right in the upper layer and to the left in the lower layer. The vertical structures of two principal semi-diurnal constituents-M2 and S2-were similar, which indicates that the tidal currents are mainly barotropic in this area. The main features of the variation of the four principal tidal constituents with depth demonstrate that the currents in this region are influenced by the upper and lower boundary layers. Therefore, the tidal constituents of the shallow water are similar. Different vertical modes were calculated based on the Empirical Orthogonal Function (EOF) analysis of the Eastern and Northern components of the tidal currents, with a variance contribution for the zero-order model of at least 90%. The variance contribution of the baroclinic model is minimal, which further reveals a strong barotropic character for the tidal currents of this region.
基金supported by the National Natural Science Foundation of China under GrantNo.61003067the National Basic ResearchProgram(973 Program)under Grants No.2013CB329102,No.2011CB302704the National Natural Science Foundation of Chinaunder Grants No.61132001,No.61171102,No.61001118
文摘Service-oriented business process generation is a key activity in the ServiceOriented Architecture(SOA)business lifecycle,and most of the other activities such as application execution depend on the business process being developed.After the business requirements are acquired,a developer has to use specific programming technologies to orchestrate web services to generate a deployable business process.It is time-consuming to specify all the business processes from lowlevel web services,especially for an enterprise that focuses on a series of similar businesses.This paper proposes a rapid service-oriented business process generation method with domain-specific assets specified in ontology systems.Assets with different levels of granularity are reused to refine the high level business process framework for executable business processes using the Business Process Executional Language(BPEL).The new methodology significantly simplifies service-oriented business process generation by reusing assets to construct business processes.A business process generation tool is also implemented to support the efficient visual design of SOA processes with the proposed method.This paper verifies the proposed method using a shipment tracking case.The studies show that the number of reusable assets increases significantly as these projects progress,and the business process generation speed also increases at the same time.
文摘Inclination of capital groups--which realize widening impact field of media-to media sector due to relationships based on interests, and relationships/dilemmata between the governing parties and the capital owners have paved the way for a unilateral media structure not hearing the voice of others/local people. It is seen that the main stream media becomes more and more under direction of capital groups. Because of the effects created by the Second World War II, also war and media relation has gain different dimensions. Together with this differentiation, a new notion was born in the field of journalism during occupation period of the lraq by the USA--Embedded Journalism This notion, called as ＂embedded journalism＂ in English can be translated as ＂yapismislik--attachment＂, ＂gomulmusluk---embeddedness＂, and ＂yamanmis-patched＂ in Turkish. In this connection, developments which have also been realized in the media economics in line with globalization process as seen all other aspects of life, changing of ownership structure in the media, and increase of concentrations, monopolization will be scrutinized in our study in addition how the fact of embedded journalism has affected the most important mission of journalism, objectivity within the framework of relations between journalism and government.
文摘Through analysis of cloud computing and characteristics, the paper described cloud computing infrastructure architecture. Mainly discusses cloud computing advantages in the use of the library and the use should pay attention to the problem, on this basis, we propose a cloud- based library information platform construction model to analyze the basic architecture of cloud computing, cloud-depth study calculated at the library information platform and database access patterns operating mode, and cloud computing future development and application prospects.
