正在研发的中国聚变工程实验堆(China Fusion Engineering Test Reactor,CFETR)集成设计平台包括物理设计平台和工程设计平台,工程设计平台采用模块化方式,包括磁体、真空室、偏滤器、中子学等模块。模块设计中涉及用计算流体动力学(Com...正在研发的中国聚变工程实验堆(China Fusion Engineering Test Reactor,CFETR)集成设计平台包括物理设计平台和工程设计平台,工程设计平台采用模块化方式,包括磁体、真空室、偏滤器、中子学等模块。模块设计中涉及用计算流体动力学(Computational Fluid Dynamics,CFD)软件来对堆内部件开展热工水力分析,CFD的热源项包括中子学计算产生的核热,而中子学分析软件(如Monte Carlo N particle transport code,MCNP)核热输出结果文件存在CFD软件无法直接读取等问题。因此,基于网格-网格插值和点-点插值法,开发了中子学与CFD核热耦合模块,提供两种途径实现高精度的三维核热耦合。使用CFX软件,以CFETR的一种氦冷陶瓷包层(Helium Cooled Ceramic Breeder blanket,HCCB)中增殖单元模块为对象,进行了热工水力分析,计算结果表明了核热耦合模块功能的可靠性。展开更多
This paper focuses on some key problems in web community discovery and link analysis.Based on the topic-oriented technology,the characteristics of a bipartite graph are studied.An Х bipartite core set is introduced t...This paper focuses on some key problems in web community discovery and link analysis.Based on the topic-oriented technology,the characteristics of a bipartite graph are studied.An Х bipartite core set is introduced to more clearly define extracting ways.By scanning the topic subgraph to construct Х bipartite graph and then prune the graph with i and j ,an Х bipartite core set,which is also the minimum element of a community,can be found.Finally,a hierarchical clustering algorithm is applied to many Х bipartite core sets and the dendrogram of the community inner construction is obtained.The correctness of the constructing and pruning method is proved and the algorithm is designed.The typical datasets in the experiment are prepared according to the way in HITS（hyperlink-induced topic search）.Ten topics and four search engines are chosen and the returned results are integrated.The modularity,which is a measure of the strength of the community structure in the social network,is used to validate the efficiency of the proposed method.The experimental results show that the proposed algorithm is effective and efficient.展开更多
The aim of this paper is to present the main results arisen from the joint efforts of the public-private partnership in being between CCII （Centro Cultura Innovativa d＇Impresa） of University of Salento and Apphia s...The aim of this paper is to present the main results arisen from the joint efforts of the public-private partnership in being between CCII （Centro Cultura Innovativa d＇Impresa） of University of Salento and Apphia s.r.l.. This paper will focus on the results of the core of the OBSS （on board stability system） module that, starting from the exact 3D geometry of a ship hull, described by a discrete model in a standard format, the distribution of all weights onboard and the data acquired by the system, calculates ship floating conditions （in draught, heel and trim）. The proposed approach is based on geometry meshes represented by an universally accepted file format （named OBJ） first developed by Wavefront Technologies. Demonstration of the validity of the results is done by the authors using as hull model a simple rectangular box.展开更多
Kernel hooks are very important con- trol data in OS kernel. Once these data are com- promised by attackers, they can change the control flow of OS kemel＇s execution. Previ- ous solutions suffer from limitations in t...Kernel hooks are very important con- trol data in OS kernel. Once these data are com- promised by attackers, they can change the control flow of OS kemel＇s execution. Previ- ous solutions suffer from limitations in that： 1） some methods require modifying the source code of OS kernel and kernel modules, which is less practical for wide deployment; 2） other methods cannot well protect the kernel hooks and function return addresses inside kernel mo- dules whose memory locations cannot be pre- determined. To address these problems, we propose OPKH, an on-the-fly hook protection system based on the virtualization technology. Compared with previous solutions, OPKH off- ers the protected OS a fully transparent envi- ronment and an easy deployment. In general, the working procedure of OPKH can be di- vided into two steps. First, we utilise the me- mory virtualization for offiine profiling so that the dynamic hooks can be identified. Second, we exploit the online patching technique to in- strument the hooks for run-time protection. The experiments show that our system can pro- tect the dynamic hooks effectively with mini- mal performance overhead.展开更多
Heap overflow attack is one of the major memory corruption attacks that have become prevalent for decades. To defeat this attack,many protection methods are proposed in recent years. However,most of these existing met...Heap overflow attack is one of the major memory corruption attacks that have become prevalent for decades. To defeat this attack,many protection methods are proposed in recent years. However,most of these existing methods focus on user-level heap overflow detection. Only a few methods are proposed for kernel heap protection. Moreover,all these kernel protection methods need modifying the existing OS kernel so that they may not be adopted in practice. To address this problem,we propose a lightweight virtualization-based solution that can protect the kernel heap buffers allocated for the target kernel modules. The key idea of our approach is to combine the static binary analysis and virtualization technology to trap a memory allocation operation of the target kernel module,and then add one secure canary word to the end of the allocated buffer. After that,a monitor process is launched to check the integrity of the canaries. The evaluations show that our system can detect kernel heap overflow attacks effectively with minimal performance cost.展开更多
The author＇s process of cold fusion, was announced to International Conference on Emerging Nuclear Energy Systems in 2007, then exposed to International Conference on Emerging Nuclear Energy Systems in 2009, and has ...The author＇s process of cold fusion, was announced to International Conference on Emerging Nuclear Energy Systems in 2007, then exposed to International Conference on Emerging Nuclear Energy Systems in 2009, and has been applied since June, 2007 in a non-member border country of the European Union, for safety reasons, the product, of a large module of 300 cm x 40 cm, using energy of mass of 600 megawatts per hour, and unique waste, 300 cubic meters of pure water a day, instantly drinkable. The presentation which the author shall make, will contain, if it is possible, several demonstrations of a portable module, producing one megawatt per hour, and in waste one cubic meter of water per day： the authors are able to stop the module at any time. The civil applications of this process, the author developed in the articles published on the site of the European Scientific Parliament 2010, and diverse modules were the object of a protocol signed by large Asian country.展开更多
The author＇s Process of Cold Fusion firstly was announced at the International Conference on Emerging Nuclear Energy Systems in 2007, after that it was presented at the International Conference on Emerging Nuclear En...The author＇s Process of Cold Fusion firstly was announced at the International Conference on Emerging Nuclear Energy Systems in 2007, after that it was presented at the International Conference on Emerging Nuclear Energy Systems in 2009. The product has already been applied since June, 2007. It was developed as a large Module of 300 cm x 40 cm, producing energy at 600 megawatts per hour, with unique waste of about 300 cubic meters of pure drinkable instant water a day. There is also a Portable Module, producing about 1 megawatt per hour, having in waste about 1 cubic meter of pure drinkable instant water a day. The important details： （1） we have the ability to stop the Module at any time; （2） the civil applications of this process is mentioned at the articles, published on the website of the European Scientific Parliament in the year of 2010; （3） the diverse modules became the object of special protocols, signed with a number of countries all over the world.展开更多
Fixed-point attractors with global stability manifest themselves in a number of gene regulatory networks. This property indicates the stability of regulatory networks against small state perturbations and is closely r...Fixed-point attractors with global stability manifest themselves in a number of gene regulatory networks. This property indicates the stability of regulatory networks against small state perturbations and is closely related to other complex dynamics. In this paper, we aim to reveal the core modules in regulatory networks that determine their global attractors and the relationship between these core modules and other motifs. This work has been done via three steps. Firstly, inspired by the signal transmission in the regulation process, we extract the model of chain-like network from regulation networks. We propose a module of "ideal transmission chain(ITC)", which is proved sufficient and necessary(under certain condition) to form a global fixed-point in the context of chain-like network. Secondly, by examining two well-studied regulatory networks(i.e., the cell-cycle regulatory networks of Budding yeast and Fission yeast), we identify the ideal modules in true regulation networks and demonstrate that the modules have a superior contribution to network stability(quantified by the relative size of the biggest attraction basin). Thirdly, in these two regulation networks, we find that the double negative feedback loops, which are the key motifs of forming bistability in regulation, are connected to these core modules with high network stability. These results have shed new light on the connection between the topological feature and the dynamic property of regulatory networks.展开更多
文摘正在研发的中国聚变工程实验堆(China Fusion Engineering Test Reactor,CFETR)集成设计平台包括物理设计平台和工程设计平台,工程设计平台采用模块化方式,包括磁体、真空室、偏滤器、中子学等模块。模块设计中涉及用计算流体动力学(Computational Fluid Dynamics,CFD)软件来对堆内部件开展热工水力分析,CFD的热源项包括中子学计算产生的核热,而中子学分析软件(如Monte Carlo N particle transport code,MCNP)核热输出结果文件存在CFD软件无法直接读取等问题。因此,基于网格-网格插值和点-点插值法,开发了中子学与CFD核热耦合模块,提供两种途径实现高精度的三维核热耦合。使用CFX软件,以CFETR的一种氦冷陶瓷包层(Helium Cooled Ceramic Breeder blanket,HCCB)中增殖单元模块为对象,进行了热工水力分析,计算结果表明了核热耦合模块功能的可靠性。
基金The National Natural Science Foundation of China(No.60773216)the National High Technology Research and Development Program of China(863Program)(No.2006AA010109)+1 种基金the Natural Science Foundation of Renmin University of China(No.06XNB052)Free Exploration Project(985 Project of Renmin University of China)(No.21361231)
文摘This paper focuses on some key problems in web community discovery and link analysis.Based on the topic-oriented technology,the characteristics of a bipartite graph are studied.An Х bipartite core set is introduced to more clearly define extracting ways.By scanning the topic subgraph to construct Х bipartite graph and then prune the graph with i and j ,an Х bipartite core set,which is also the minimum element of a community,can be found.Finally,a hierarchical clustering algorithm is applied to many Х bipartite core sets and the dendrogram of the community inner construction is obtained.The correctness of the constructing and pruning method is proved and the algorithm is designed.The typical datasets in the experiment are prepared according to the way in HITS（hyperlink-induced topic search）.Ten topics and four search engines are chosen and the returned results are integrated.The modularity,which is a measure of the strength of the community structure in the social network,is used to validate the efficiency of the proposed method.The experimental results show that the proposed algorithm is effective and efficient.
文摘The aim of this paper is to present the main results arisen from the joint efforts of the public-private partnership in being between CCII （Centro Cultura Innovativa d＇Impresa） of University of Salento and Apphia s.r.l.. This paper will focus on the results of the core of the OBSS （on board stability system） module that, starting from the exact 3D geometry of a ship hull, described by a discrete model in a standard format, the distribution of all weights onboard and the data acquired by the system, calculates ship floating conditions （in draught, heel and trim）. The proposed approach is based on geometry meshes represented by an universally accepted file format （named OBJ） first developed by Wavefront Technologies. Demonstration of the validity of the results is done by the authors using as hull model a simple rectangular box.
基金supported in part by the National High Technology Research and Development Program of China(863 Program)under Grant No.2009AA01Z433the Project of National Ministry under Grant No.A21201-10006the Open Foundation of State Key Laboratory of Information Security(Institute of Information Engineering,Chinese Academy of Sciences)under Grant No.2013-4-1
文摘Kernel hooks are very important con- trol data in OS kernel. Once these data are com- promised by attackers, they can change the control flow of OS kemel＇s execution. Previ- ous solutions suffer from limitations in that： 1） some methods require modifying the source code of OS kernel and kernel modules, which is less practical for wide deployment; 2） other methods cannot well protect the kernel hooks and function return addresses inside kernel mo- dules whose memory locations cannot be pre- determined. To address these problems, we propose OPKH, an on-the-fly hook protection system based on the virtualization technology. Compared with previous solutions, OPKH off- ers the protected OS a fully transparent envi- ronment and an easy deployment. In general, the working procedure of OPKH can be di- vided into two steps. First, we utilise the me- mory virtualization for offiine profiling so that the dynamic hooks can be identified. Second, we exploit the online patching technique to in- strument the hooks for run-time protection. The experiments show that our system can pro- tect the dynamic hooks effectively with mini- mal performance overhead.
基金supported in part by National Natural Science Foundation of China (NSFC) under Grant No.61602035the National Key Research and Development Program of China under Grant No.2016YFB0800700+1 种基金the Opening Project of Shanghai Key Laboratory of Integrated Administration Technologies for Information SecurityOpen Found of Key Laboratory of IOT Application Technology of Universities in Yunnan Province under Grant No.2015IOT03
文摘Heap overflow attack is one of the major memory corruption attacks that have become prevalent for decades. To defeat this attack,many protection methods are proposed in recent years. However,most of these existing methods focus on user-level heap overflow detection. Only a few methods are proposed for kernel heap protection. Moreover,all these kernel protection methods need modifying the existing OS kernel so that they may not be adopted in practice. To address this problem,we propose a lightweight virtualization-based solution that can protect the kernel heap buffers allocated for the target kernel modules. The key idea of our approach is to combine the static binary analysis and virtualization technology to trap a memory allocation operation of the target kernel module,and then add one secure canary word to the end of the allocated buffer. After that,a monitor process is launched to check the integrity of the canaries. The evaluations show that our system can detect kernel heap overflow attacks effectively with minimal performance cost.
文摘The author＇s process of cold fusion, was announced to International Conference on Emerging Nuclear Energy Systems in 2007, then exposed to International Conference on Emerging Nuclear Energy Systems in 2009, and has been applied since June, 2007 in a non-member border country of the European Union, for safety reasons, the product, of a large module of 300 cm x 40 cm, using energy of mass of 600 megawatts per hour, and unique waste, 300 cubic meters of pure water a day, instantly drinkable. The presentation which the author shall make, will contain, if it is possible, several demonstrations of a portable module, producing one megawatt per hour, and in waste one cubic meter of water per day： the authors are able to stop the module at any time. The civil applications of this process, the author developed in the articles published on the site of the European Scientific Parliament 2010, and diverse modules were the object of a protocol signed by large Asian country.
文摘The author＇s Process of Cold Fusion firstly was announced at the International Conference on Emerging Nuclear Energy Systems in 2007, after that it was presented at the International Conference on Emerging Nuclear Energy Systems in 2009. The product has already been applied since June, 2007. It was developed as a large Module of 300 cm x 40 cm, producing energy at 600 megawatts per hour, with unique waste of about 300 cubic meters of pure drinkable instant water a day. There is also a Portable Module, producing about 1 megawatt per hour, having in waste about 1 cubic meter of pure drinkable instant water a day. The important details： （1） we have the ability to stop the Module at any time; （2） the civil applications of this process is mentioned at the articles, published on the website of the European Scientific Parliament in the year of 2010; （3） the diverse modules became the object of special protocols, signed with a number of countries all over the world.
基金supported by the National Natural Science Foundation of China(Grant No.11331011)Support from the Center for Statistical Science of Peking University was also gratefully acknowledged
文摘Fixed-point attractors with global stability manifest themselves in a number of gene regulatory networks. This property indicates the stability of regulatory networks against small state perturbations and is closely related to other complex dynamics. In this paper, we aim to reveal the core modules in regulatory networks that determine their global attractors and the relationship between these core modules and other motifs. This work has been done via three steps. Firstly, inspired by the signal transmission in the regulation process, we extract the model of chain-like network from regulation networks. We propose a module of "ideal transmission chain(ITC)", which is proved sufficient and necessary(under certain condition) to form a global fixed-point in the context of chain-like network. Secondly, by examining two well-studied regulatory networks(i.e., the cell-cycle regulatory networks of Budding yeast and Fission yeast), we identify the ideal modules in true regulation networks and demonstrate that the modules have a superior contribution to network stability(quantified by the relative size of the biggest attraction basin). Thirdly, in these two regulation networks, we find that the double negative feedback loops, which are the key motifs of forming bistability in regulation, are connected to these core modules with high network stability. These results have shed new light on the connection between the topological feature and the dynamic property of regulatory networks.
