A multiple secret sharing scheme can share a group of secrets in each sharing session, which is very useful especially in sharing large secrets. However, most of the existing multiple secret sharing schemes are （t, n...A multiple secret sharing scheme can share a group of secrets in each sharing session, which is very useful especially in sharing large secrets. However, most of the existing multiple secret sharing schemes are （t, n） threshold schemes, so they are fit for only threshold applications and unfit for the applications of general access structures. Due to the fact that a （t, n） threshold scheme could only handle a small fraction of the secret sharing idea, a novel multi-secret sharing scheme is proposed, which is designed based on general access structures. The security of this scheme is the same as that of Shamir＇s threshold secret sharing scheme. Compared with the existing multiple secret sharing schemes, the proposed scheme can provide greater capabilities for many applications because it is able to deal with applications of general access structures.展开更多
Under the requirement of everything over IP, network service shows the following characteristics:(1) network service increases its richness;(2) broadband streaming media becomes the mainstream. To achieve unified mult...Under the requirement of everything over IP, network service shows the following characteristics:(1) network service increases its richness;(2) broadband streaming media becomes the mainstream. To achieve unified multi-service bearing in the IP network, the largescale access convergence network architecture is proposed. This flat access convergence structure with ultra-small hops, which shortens the service transmission path, reduces the complexity of the edge of the network, and achieves IP strong waist model with the integration of computation, storage and transmission. The key technologies are also introduced in this paper, including endto-end performance guarantee for real time interactive services, fog storing mechanism, and built-in safety transmission with integration of aggregation and control.展开更多
For the applied limitation of the existing threshold decryption schemes based on the(t,n) structure, an identity-based threshold decryption scheme which can be applied on the access structure is proposed through desig...For the applied limitation of the existing threshold decryption schemes based on the(t,n) structure, an identity-based threshold decryption scheme which can be applied on the access structure is proposed through designing a special distribution algorithm of the private key shares.The generation and distribution of private key shares,the encryption,the decryption and the combination are introduced in detail.The validity and security of the scheme are proved and analyzed.Comparisons with the existing schemes show that the proposed scheme is more flexible.展开更多
Memory access fast switching structures in cluster are studied,and three kinds of fast switching structures（ FS,LR2 SS,and LAPS） are proposed. A mixed simulation test bench is constructed and used for statistic of d...Memory access fast switching structures in cluster are studied,and three kinds of fast switching structures（ FS,LR2 SS,and LAPS） are proposed. A mixed simulation test bench is constructed and used for statistic of data access delay among these three structures in various cases. Finally these structures are realized on Xilinx FPGA development board and DCT,FFT,SAD,IME,FME,and de-blocking filtering algorithms are mapped onto the structures. Compared with available architectures,our proposed structures have lower data access delay and lower area.展开更多
A group oriented cryptosystem for the vector space access structure was proposed. This cryptosystem adopts self-certified public keys. It allows the participants of an authorized subset to cooperatively access an encr...A group oriented cryptosystem for the vector space access structure was proposed. This cryptosystem adopts self-certified public keys. It allows the participants of an authorized subset to cooperatively access an encrypted message. All data delivered in the cryptosystem are public. Therefore it does not need a partial decrypting results combiner and any secure communication channel. The security of the group oriented cryptosystem is based on the intractability of the discrete log problem and difficulty of factoring large integers. The suspected attacks can not break it.展开更多
Natural gas is expected to play a much more important role in China in future decades, and market reform is crucial for its rapid market penetration. At present, the main gas fields, pipelines and liquefied natural ga...Natural gas is expected to play a much more important role in China in future decades, and market reform is crucial for its rapid market penetration. At present, the main gas fields, pipelines and liquefied natural gas(LNG) infrastructure are mainly monopolized by large state-owned companies, and one of the important market reform policies is to open up LNG import rights to smaller private companies and traders. Therefore, in the present study, a game theoretical model is proposed to analyze and compare the impacts of different market structures on infrastructure deployment and social welfare. Moreover, a support vector machine-based rolling horizon stochastic method is adopted in the model to simulate real LNG price fluctuations. Four market reform scenarios are proposed considering different policies such as business separation, third-party access(TPA) and their combinations. The results indicate that, with third-party access(TPA)entrance into the LNG market, the construction of LNG infrastructure will be promoted and more gas will be provided at lower prices, and thus the total social welfare will be improved greatly.展开更多
Membrane proteins are an important kind of proteins embedded in the membranes of cells and play crucial roles in living organisms, such as ion channels,transporters, receptors. Because it is difficult to determinate t...Membrane proteins are an important kind of proteins embedded in the membranes of cells and play crucial roles in living organisms, such as ion channels,transporters, receptors. Because it is difficult to determinate the membrane protein's structure by wet-lab experiments,accurate and fast amino acid sequence-based computational methods are highly desired. In this paper, we report an online prediction tool called Mem Brain, whose input is the amino acid sequence. Mem Brain consists of specialized modules for predicting transmembrane helices, residue–residue contacts and relative accessible surface area of a-helical membrane proteins. Mem Brain achieves aprediction accuracy of 97.9% of ATMH, 87.1% of AP,3.2 ± 3.0 of N-score, 3.1 ± 2.8 of C-score. Mem BrainContact obtains 62%/64.1% prediction accuracy on training and independent dataset on top L/5 contact prediction,respectively. And Mem Brain-Rasa achieves Pearson correlation coefficient of 0.733 and its mean absolute error of13.593. These prediction results provide valuable hints for revealing the structure and function of membrane proteins.Mem Brain web server is free for academic use and available at www.csbio.sjtu.edu.cn/bioinf/Mem Brain/.展开更多
This paper analyzed characteristics of tourism resources in Ji'an City,and carried out quantitative analysis of local tourism resources based on agglomeration effect of resources,connectivity analysis,and accessib...This paper analyzed characteristics of tourism resources in Ji'an City,and carried out quantitative analysis of local tourism resources based on agglomeration effect of resources,connectivity analysis,and accessibility analysis. The results showed that the city has poor loop of tourism network,major scenic areas(spots) have moderate network accessibility,in view of this,suggestions for the optimum development of local tourism industry were proposed.展开更多
In this paper the authors wish to introduce an application of the gravitational model through two concrete examples. In their investigation the gravitational model was transformed to analyze the spatial structure of E...In this paper the authors wish to introduce an application of the gravitational model through two concrete examples. In their investigation the gravitational model was transformed to analyze the spatial structure of Europe, and the impact of accessibility in Hungary. In this analysis not only the size of gravitational forces but their direction can also be measured. Displacements were illustrated by a bi-dimensional regression, which gives a new perspective to the investigation of spatial structure.展开更多
Recently, a tunable fiber Bragg grating(FBG) was developed by using stress-responsive colloidal crystals. In this paper, we have simulated the application of these nanoparticles into the super-structured fiber Bragg g...Recently, a tunable fiber Bragg grating(FBG) was developed by using stress-responsive colloidal crystals. In this paper, we have simulated the application of these nanoparticles into the super-structured fiber Bragg grating(SSFBG) written with perfect sequences derived from a short maximal-length sequence. A tunable SSFBG will be available to overcome the prohibitive temperature variation of the optical codecs. Nevertheless,we presented a method to implement coherent time spreading optical code-division multiple-access(OCDMA) where a unique code(or perfect sequence) can be reused and mixed with different wavelengths to obtain a tunable wavelength-division multiplexing(WDM)system. In order to maximize the binary throughput, we have selected a unique short maximal-length sequence composed of 7 chips that can be tuned with 7 different optical wavelengths. We found thousands of different tunable combinations that presented power contrast ratios(P/C) higher than 12 dB. When a WDM-OCDMA system used 2 different combinations simultaneously, the perfect binary detection with error correction codes was achieved successfully. The tunable SSFBG with colloidal crystals will be a simple and good alternative choice for fiber-to-the-home(FTTH) communications.展开更多
From the development of modern transportation to the current era of high-speed transportation networks, the Beijing-Tianjin-Hebei(BTH) region has always played a national leading role in land transportation developmen...From the development of modern transportation to the current era of high-speed transportation networks, the Beijing-Tianjin-Hebei(BTH) region has always played a national leading role in land transportation development of China. In order to explore the long-term evolutionary characteristics of land transportation in the BTH region, this paper utilized a temporal scale of 100 years to systematically interpret the development process of the land transportation network. Taking 13 cities within the BTH region as research anchor cities, we took into account "leaping" mode of transportation in order to investigate the evolution of accessibility. Our research shows the following results:(1) The land transportation network in the BTH region has undergone five stages of development: the initial period of modernization(1881–1937); the period of stagnation of transportation development(1937–1949); the network expansion period(1949–1980); the period of trunk construction(1980–1995), and the period of high-speed transportation network development(1995–present). The network structure centered around Beijing has existed from the outset of modern transportation development.(2) The accessibility spatial pattern of land transportation in BTH region has evolved from expansion along traffic corridors to the formation of concentric circles. The stratified circular structure of transportation in anchor cities has gradually developed into a contiguous development pattern.(3) There are clear hierarchical differences in the transportation structures of anchor cities. Beijing has always been at the top of this hierarchy, while the hierarchical position of Zhangjiakou has fallen noticeably since 1949. The Beijing-Tianjin region was the first region to form a short-duration transportation circle structure, while the transportation advantages of the central part of Hebei Province, which is located in the center of the BTH transportation region, have yet to be realized.展开更多
Predicted relative solvent accessibility (RSA) provides useful information for prediction of binding sites and reconstruction of the 3D-structure based on a protein sequence. Recent years observed development of sever...Predicted relative solvent accessibility (RSA) provides useful information for prediction of binding sites and reconstruction of the 3D-structure based on a protein sequence. Recent years observed development of several RSA prediction methods including those that generate real values and those that predict discrete states (buried vs. exposed). We propose a novel method for real value prediction that aims at minimizing the prediction error when compared with six existing methods. The proposed method is based on a two-stage Support Vector Regression (SVR) predictor. The improved prediction quality is a result of the developed composite sequence representation, which includes a custom-selected subset of features from the PSI-BLAST profile, secondary structure predicted with PSI-PRED, and binary code that indicates position of a given residue with respect to sequence termini. Cross validation tests on a benchmark dataset show that our method achieves 14.3 mean absolute error and 0.68 correlation. We also propose a confidence value that is associated with each predicted RSA values. The confidence is computed based on the difference in predictions from the two-stage SVR and a second two-stage Linear Regression (LR) predictor. The confidence values can be used to indicate the quality of the output RSA predictions.展开更多
本文针对高校财务报销流程中存在的信任缺失、报销效率低下等问题,提出了一种以项目为导向的区块链高校报销平台模型。针对多项目环境下参与者角色的动态性,引入基于属性的访问控制(attribute-based access control,ABAC)模型,实现了细...本文针对高校财务报销流程中存在的信任缺失、报销效率低下等问题,提出了一种以项目为导向的区块链高校报销平台模型。针对多项目环境下参与者角色的动态性,引入基于属性的访问控制(attribute-based access control,ABAC)模型,实现了细粒度的权限管理。针对传统单链结构难以有效处理项目和发票之间的复杂逻辑关系,设计了主链-副链的双链存储结构以及对应的逻辑交易算法,解决了不同报销状态及与项目之间复杂的对应关系。为提高查询效率,设计了一种基于Merkle树索引表(Merkle tree index table,MTIT)的查询算法。实验结果表明,本设计在不同交易量下均展现出良好的性能稳定性,能够满足高校日常财务管理的需求。展开更多
基金Supported bythe National Basic Research Programof China(973 Program G1999035805)
文摘A multiple secret sharing scheme can share a group of secrets in each sharing session, which is very useful especially in sharing large secrets. However, most of the existing multiple secret sharing schemes are （t, n） threshold schemes, so they are fit for only threshold applications and unfit for the applications of general access structures. Due to the fact that a （t, n） threshold scheme could only handle a small fraction of the secret sharing idea, a novel multi-secret sharing scheme is proposed, which is designed based on general access structures. The security of this scheme is the same as that of Shamir＇s threshold secret sharing scheme. Compared with the existing multiple secret sharing schemes, the proposed scheme can provide greater capabilities for many applications because it is able to deal with applications of general access structures.
基金supported by The National Key Technology R&D Program (Grant No. 2011BAH19B00)The National Basic Research Program of China (973) (Grant No. 2012CB315900)The National High Technology Research and Development Program of China (863) (Grant No. 2015AA016102)
文摘Under the requirement of everything over IP, network service shows the following characteristics:(1) network service increases its richness;(2) broadband streaming media becomes the mainstream. To achieve unified multi-service bearing in the IP network, the largescale access convergence network architecture is proposed. This flat access convergence structure with ultra-small hops, which shortens the service transmission path, reduces the complexity of the edge of the network, and achieves IP strong waist model with the integration of computation, storage and transmission. The key technologies are also introduced in this paper, including endto-end performance guarantee for real time interactive services, fog storing mechanism, and built-in safety transmission with integration of aggregation and control.
基金the National Natural Science Foundation of China(No.60374066)
文摘For the applied limitation of the existing threshold decryption schemes based on the(t,n) structure, an identity-based threshold decryption scheme which can be applied on the access structure is proposed through designing a special distribution algorithm of the private key shares.The generation and distribution of private key shares,the encryption,the decryption and the combination are introduced in detail.The validity and security of the scheme are proved and analyzed.Comparisons with the existing schemes show that the proposed scheme is more flexible.
基金Supported by the National Natural Science Foundation of China(61272120,61634004,61602377)the Shaanxi Provincial Co-ordination Innovation Project of Science and Technology(2016KTZDGY02-04-02)Scientific Research Program Funded by Shannxi Provincial Education Department(17JK0689)
文摘Memory access fast switching structures in cluster are studied,and three kinds of fast switching structures（ FS,LR2 SS,and LAPS） are proposed. A mixed simulation test bench is constructed and used for statistic of data access delay among these three structures in various cases. Finally these structures are realized on Xilinx FPGA development board and DCT,FFT,SAD,IME,FME,and de-blocking filtering algorithms are mapped onto the structures. Compared with available architectures,our proposed structures have lower data access delay and lower area.
文摘A group oriented cryptosystem for the vector space access structure was proposed. This cryptosystem adopts self-certified public keys. It allows the participants of an authorized subset to cooperatively access an encrypted message. All data delivered in the cryptosystem are public. Therefore it does not need a partial decrypting results combiner and any secure communication channel. The security of the group oriented cryptosystem is based on the intractability of the discrete log problem and difficulty of factoring large integers. The suspected attacks can not break it.
基金financial support of the National Natural Science Foundation of China (Grant No. 71774171)Science Foundation of China University of Petroleum, Beijing (No. 2462017YB11)
文摘Natural gas is expected to play a much more important role in China in future decades, and market reform is crucial for its rapid market penetration. At present, the main gas fields, pipelines and liquefied natural gas(LNG) infrastructure are mainly monopolized by large state-owned companies, and one of the important market reform policies is to open up LNG import rights to smaller private companies and traders. Therefore, in the present study, a game theoretical model is proposed to analyze and compare the impacts of different market structures on infrastructure deployment and social welfare. Moreover, a support vector machine-based rolling horizon stochastic method is adopted in the model to simulate real LNG price fluctuations. Four market reform scenarios are proposed considering different policies such as business separation, third-party access(TPA) and their combinations. The results indicate that, with third-party access(TPA)entrance into the LNG market, the construction of LNG infrastructure will be promoted and more gas will be provided at lower prices, and thus the total social welfare will be improved greatly.
基金supported by the National Natural Science Foundation of China(Nos.61671288,91530321,61603161)Science and Technology Commission of Shanghai Municipality(Nos.16JC1404300,17JC1403500,16ZR1448700)
文摘Membrane proteins are an important kind of proteins embedded in the membranes of cells and play crucial roles in living organisms, such as ion channels,transporters, receptors. Because it is difficult to determinate the membrane protein's structure by wet-lab experiments,accurate and fast amino acid sequence-based computational methods are highly desired. In this paper, we report an online prediction tool called Mem Brain, whose input is the amino acid sequence. Mem Brain consists of specialized modules for predicting transmembrane helices, residue–residue contacts and relative accessible surface area of a-helical membrane proteins. Mem Brain achieves aprediction accuracy of 97.9% of ATMH, 87.1% of AP,3.2 ± 3.0 of N-score, 3.1 ± 2.8 of C-score. Mem BrainContact obtains 62%/64.1% prediction accuracy on training and independent dataset on top L/5 contact prediction,respectively. And Mem Brain-Rasa achieves Pearson correlation coefficient of 0.733 and its mean absolute error of13.593. These prediction results provide valuable hints for revealing the structure and function of membrane proteins.Mem Brain web server is free for academic use and available at www.csbio.sjtu.edu.cn/bioinf/Mem Brain/.
基金Supported by"Twelfth Five-year Plan"of Social Science Research Program of Jilin Provincial Development of Education(2012NO.532,2013NO.333)
文摘This paper analyzed characteristics of tourism resources in Ji'an City,and carried out quantitative analysis of local tourism resources based on agglomeration effect of resources,connectivity analysis,and accessibility analysis. The results showed that the city has poor loop of tourism network,major scenic areas(spots) have moderate network accessibility,in view of this,suggestions for the optimum development of local tourism industry were proposed.
文摘In this paper the authors wish to introduce an application of the gravitational model through two concrete examples. In their investigation the gravitational model was transformed to analyze the spatial structure of Europe, and the impact of accessibility in Hungary. In this analysis not only the size of gravitational forces but their direction can also be measured. Displacements were illustrated by a bi-dimensional regression, which gives a new perspective to the investigation of spatial structure.
文摘Recently, a tunable fiber Bragg grating(FBG) was developed by using stress-responsive colloidal crystals. In this paper, we have simulated the application of these nanoparticles into the super-structured fiber Bragg grating(SSFBG) written with perfect sequences derived from a short maximal-length sequence. A tunable SSFBG will be available to overcome the prohibitive temperature variation of the optical codecs. Nevertheless,we presented a method to implement coherent time spreading optical code-division multiple-access(OCDMA) where a unique code(or perfect sequence) can be reused and mixed with different wavelengths to obtain a tunable wavelength-division multiplexing(WDM)system. In order to maximize the binary throughput, we have selected a unique short maximal-length sequence composed of 7 chips that can be tuned with 7 different optical wavelengths. We found thousands of different tunable combinations that presented power contrast ratios(P/C) higher than 12 dB. When a WDM-OCDMA system used 2 different combinations simultaneously, the perfect binary detection with error correction codes was achieved successfully. The tunable SSFBG with colloidal crystals will be a simple and good alternative choice for fiber-to-the-home(FTTH) communications.
基金National Natural Science Foundation of China,No.41701122,No.41430635China Postdoctoral Science Foundation,No.2017M611854,No.2016M600356
文摘From the development of modern transportation to the current era of high-speed transportation networks, the Beijing-Tianjin-Hebei(BTH) region has always played a national leading role in land transportation development of China. In order to explore the long-term evolutionary characteristics of land transportation in the BTH region, this paper utilized a temporal scale of 100 years to systematically interpret the development process of the land transportation network. Taking 13 cities within the BTH region as research anchor cities, we took into account "leaping" mode of transportation in order to investigate the evolution of accessibility. Our research shows the following results:(1) The land transportation network in the BTH region has undergone five stages of development: the initial period of modernization(1881–1937); the period of stagnation of transportation development(1937–1949); the network expansion period(1949–1980); the period of trunk construction(1980–1995), and the period of high-speed transportation network development(1995–present). The network structure centered around Beijing has existed from the outset of modern transportation development.(2) The accessibility spatial pattern of land transportation in BTH region has evolved from expansion along traffic corridors to the formation of concentric circles. The stratified circular structure of transportation in anchor cities has gradually developed into a contiguous development pattern.(3) There are clear hierarchical differences in the transportation structures of anchor cities. Beijing has always been at the top of this hierarchy, while the hierarchical position of Zhangjiakou has fallen noticeably since 1949. The Beijing-Tianjin region was the first region to form a short-duration transportation circle structure, while the transportation advantages of the central part of Hebei Province, which is located in the center of the BTH transportation region, have yet to be realized.
文摘Predicted relative solvent accessibility (RSA) provides useful information for prediction of binding sites and reconstruction of the 3D-structure based on a protein sequence. Recent years observed development of several RSA prediction methods including those that generate real values and those that predict discrete states (buried vs. exposed). We propose a novel method for real value prediction that aims at minimizing the prediction error when compared with six existing methods. The proposed method is based on a two-stage Support Vector Regression (SVR) predictor. The improved prediction quality is a result of the developed composite sequence representation, which includes a custom-selected subset of features from the PSI-BLAST profile, secondary structure predicted with PSI-PRED, and binary code that indicates position of a given residue with respect to sequence termini. Cross validation tests on a benchmark dataset show that our method achieves 14.3 mean absolute error and 0.68 correlation. We also propose a confidence value that is associated with each predicted RSA values. The confidence is computed based on the difference in predictions from the two-stage SVR and a second two-stage Linear Regression (LR) predictor. The confidence values can be used to indicate the quality of the output RSA predictions.
文摘本文针对高校财务报销流程中存在的信任缺失、报销效率低下等问题,提出了一种以项目为导向的区块链高校报销平台模型。针对多项目环境下参与者角色的动态性,引入基于属性的访问控制(attribute-based access control,ABAC)模型,实现了细粒度的权限管理。针对传统单链结构难以有效处理项目和发票之间的复杂逻辑关系,设计了主链-副链的双链存储结构以及对应的逻辑交易算法,解决了不同报销状态及与项目之间复杂的对应关系。为提高查询效率,设计了一种基于Merkle树索引表(Merkle tree index table,MTIT)的查询算法。实验结果表明,本设计在不同交易量下均展现出良好的性能稳定性,能够满足高校日常财务管理的需求。
