Public key encryption scheme with keyword search (PEKS) enables us to search the encrypted data in a cloud server with a keyword, and no one can obtain any infor- mation about the encrypted data without the trapdoor...Public key encryption scheme with keyword search (PEKS) enables us to search the encrypted data in a cloud server with a keyword, and no one can obtain any infor- mation about the encrypted data without the trapdoor corresponding to the keyword. The PEKS is useful to keep the management of large data storages secure such as those in a cloud. In this paper, to protect against quantum computer attacks, we present a lattice-based identity-based encryption scheme with key- word search. We have proved that our scheme can achieve ciphertext indistinguishability in the random oracle model, and our scheme can also achieve trapdoor security. In particular, our scheme can designate a unique tester to test and return the search results, therefore it does not need a secure channel. To the best of our knowledge, our scheme is the first iden- tity-based encryption scheme with keyword search from lattice assumption.展开更多
This thesis focuses on corporate decision-making and innovation as a process of the system as a whole. The innovative nature of the activities is to change the existing state of technology or management, and that re-c...This thesis focuses on corporate decision-making and innovation as a process of the system as a whole. The innovative nature of the activities is to change the existing state of technology or management, and that re-combination of factors of production or knowledge base of the organization. Decision-making and innovation is a concentrated expression of the entrepreneurial ability and achievements. Proposed an optimized model of decision-making and innovation, and for the first time put forward the concept of "decision-making innovation manipulation critical platform" and manipulation instructions, provide a guiding framework for corporate decision-making innovation and capacity building, and has a certain practical significance.展开更多
This thesis focuses on corporate decision-making and innovation as a process of the system as a whole. The innovative nature of the activities is to change the existing state of technology or management, and that re-c...This thesis focuses on corporate decision-making and innovation as a process of the system as a whole. The innovative nature of the activities is to change the existing state of technology or management, and that re-combination of factors of production or knowledge base of the organization. Decision-making and innovation is a concentrated expression of the entrepreneurial ability and achievements. Proposed an optimized model of decision-making and innovation, and for the first time put forward the concept of "decision-making innovation manipulation critical platform" and manipulation instructions, provide a guiding framework for corporate decision-making innovation and capacity building, and has a certain practical significance.展开更多
With the advent of knowledge, knowledge has become a key resource of economic increase and growth. More and more enterprises begin to adopt knowledge management to enhance the competitiveness of enterprises, however, ...With the advent of knowledge, knowledge has become a key resource of economic increase and growth. More and more enterprises begin to adopt knowledge management to enhance the competitiveness of enterprises, however, knowledge management is not simply the use of information technology, but need to establish corresponding corporate culture environment. Therefore, building corporate culture adapting to knowledge management is an important concern.展开更多
Distributed key value storage systems are among the most important types of distributed storage systems currently deployed in data centers. Nowadays, enterprise data centers are facing growing pressure in reducing the...Distributed key value storage systems are among the most important types of distributed storage systems currently deployed in data centers. Nowadays, enterprise data centers are facing growing pressure in reducing their power consumption. In this paper, we propose GreenCHT, a reliable power management scheme for consistent hashing based distributed key value storage systems. It consists of a multi-tier replication scheme, a reliable distributed log store, and a predictive power mode scheduler (PMS). Instead of randomly placing replicas of each object on a number of nodes in the consistent hash ring, we arrange the replicas of objects on nonoverlapping tiers of nodes in the ring. This allows the system to fall in various power modes by powering down subsets of servers while not violating data availability. The predictive PMS predicts workloads and adapts to load fluctuation. It cooperates with the multi-tier replication strategy to provide power proportionality for the system. To ensure that the reliability of the system is maintained when replicas are powered down, we distribute the writes to standby replicas to active servers, which ensures failure tolerance of the system. GreenCHT is implemented based on Sheepdog, a distributed key value storage system that uses consistent hashing as an underlying distributed hash table. By replaying 12 typical real workload traces collected from Microsoft, the evaluation results show that GreenCHT can provide significant power savings while maintaining a desired performance. We observe that GreenCHT can reduce power consumption by up to 35%-61%.展开更多
Based on the covariant prolongation structure technique,we construct the integrable higher-order deformations of the(2+1)-dimensional Heisenberg ferromagnet model and obtain their su(2) × R(λ) prolongation struc...Based on the covariant prolongation structure technique,we construct the integrable higher-order deformations of the(2+1)-dimensional Heisenberg ferromagnet model and obtain their su(2) × R(λ) prolongation structures.By associating these deformed multidimensional Heisenberg ferromagnet models with the moving space curve in Euclidean space and using the Hasimoto function,we derive their geometrical equivalent counterparts,i.e.,higher-order(2+1)-dimensional nonlinear Schrdinger equations.展开更多
With increasing numbers and types of nature reserves(NRs),objective evaluation and comparison of the effects of different nature NRs on conservation efforts are of great importance for protecting species diversity,ens...With increasing numbers and types of nature reserves(NRs),objective evaluation and comparison of the effects of different nature NRs on conservation efforts are of great importance for protecting species diversity,ensuring reasonable national economic input,and adjusting government management schemes.Developing a method for the combined assessment of flagship or umbrella species and ecosystem quality will improve the evaluation of NRs.However,it is also important to establish a new framework for rapid evaluation of ecosystem quality,supported by the advantages of scientific,economic,and regular principles.Here,we proposed a new framework that incorporates the novel concept of ideal references into evaluation systems,which will facilitate the comparison of results from different periods and regions.Furthermore,from the perspective of making the framework as objective,rapid,and economical as possible,we recommended some key ecological indicators,such as net primary productivity,soil organic matter,plant diversity,for use in the new evaluation framework.The new framework,referred to as“ideal reference and key indicators”(IRKI),can sufficiently meet the requirements for the rapid evaluation of ecosystem quality both regionally and nationally.Furthermore,IRKI can identify the restoration potential and restoration periods of NRs,thus facilitating the rational distribution of resources and enhancing the protective effect.There are many types of NRs in China,and it is necessary to partially alter the assessment methods or parameters for different types of NRs.Overall,IRKI provides a simple,clear,and comparable framework that will strongly enhance the conservation of protected areas(PAs)and facilitate the standardization of management practices.展开更多
基金supported by the National Natural Science Foundation of China (No.61370203)China Postdoctoral Science Foundation Funded Project (No.2017M623008)+1 种基金Scientific Research Starting Project of SWPU (No.2017QHZ023)State Scholarship Foundation of China Scholarship Council (No.201708515149)
文摘Public key encryption scheme with keyword search (PEKS) enables us to search the encrypted data in a cloud server with a keyword, and no one can obtain any infor- mation about the encrypted data without the trapdoor corresponding to the keyword. The PEKS is useful to keep the management of large data storages secure such as those in a cloud. In this paper, to protect against quantum computer attacks, we present a lattice-based identity-based encryption scheme with key- word search. We have proved that our scheme can achieve ciphertext indistinguishability in the random oracle model, and our scheme can also achieve trapdoor security. In particular, our scheme can designate a unique tester to test and return the search results, therefore it does not need a secure channel. To the best of our knowledge, our scheme is the first iden- tity-based encryption scheme with keyword search from lattice assumption.
文摘This thesis focuses on corporate decision-making and innovation as a process of the system as a whole. The innovative nature of the activities is to change the existing state of technology or management, and that re-combination of factors of production or knowledge base of the organization. Decision-making and innovation is a concentrated expression of the entrepreneurial ability and achievements. Proposed an optimized model of decision-making and innovation, and for the first time put forward the concept of "decision-making innovation manipulation critical platform" and manipulation instructions, provide a guiding framework for corporate decision-making innovation and capacity building, and has a certain practical significance.
文摘This thesis focuses on corporate decision-making and innovation as a process of the system as a whole. The innovative nature of the activities is to change the existing state of technology or management, and that re-combination of factors of production or knowledge base of the organization. Decision-making and innovation is a concentrated expression of the entrepreneurial ability and achievements. Proposed an optimized model of decision-making and innovation, and for the first time put forward the concept of "decision-making innovation manipulation critical platform" and manipulation instructions, provide a guiding framework for corporate decision-making innovation and capacity building, and has a certain practical significance.
文摘With the advent of knowledge, knowledge has become a key resource of economic increase and growth. More and more enterprises begin to adopt knowledge management to enhance the competitiveness of enterprises, however, knowledge management is not simply the use of information technology, but need to establish corresponding corporate culture environment. Therefore, building corporate culture adapting to knowledge management is an important concern.
文摘Distributed key value storage systems are among the most important types of distributed storage systems currently deployed in data centers. Nowadays, enterprise data centers are facing growing pressure in reducing their power consumption. In this paper, we propose GreenCHT, a reliable power management scheme for consistent hashing based distributed key value storage systems. It consists of a multi-tier replication scheme, a reliable distributed log store, and a predictive power mode scheduler (PMS). Instead of randomly placing replicas of each object on a number of nodes in the consistent hash ring, we arrange the replicas of objects on nonoverlapping tiers of nodes in the ring. This allows the system to fall in various power modes by powering down subsets of servers while not violating data availability. The predictive PMS predicts workloads and adapts to load fluctuation. It cooperates with the multi-tier replication strategy to provide power proportionality for the system. To ensure that the reliability of the system is maintained when replicas are powered down, we distribute the writes to standby replicas to active servers, which ensures failure tolerance of the system. GreenCHT is implemented based on Sheepdog, a distributed key value storage system that uses consistent hashing as an underlying distributed hash table. By replaying 12 typical real workload traces collected from Microsoft, the evaluation results show that GreenCHT can provide significant power savings while maintaining a desired performance. We observe that GreenCHT can reduce power consumption by up to 35%-61%.
基金Supported by National Natural Science Foundation of China under Grant Nos. 10975102 and 11031005Beijing Municipal Commission of Education under Grant No. KZ201210028032
文摘Based on the covariant prolongation structure technique,we construct the integrable higher-order deformations of the(2+1)-dimensional Heisenberg ferromagnet model and obtain their su(2) × R(λ) prolongation structures.By associating these deformed multidimensional Heisenberg ferromagnet models with the moving space curve in Euclidean space and using the Hasimoto function,we derive their geometrical equivalent counterparts,i.e.,higher-order(2+1)-dimensional nonlinear Schrdinger equations.
基金The Chinese Academy of Sciences Strategic Priority Research Program(XDA23080401)The National Natural Science Foundation of China(32171544,31988102).
文摘With increasing numbers and types of nature reserves(NRs),objective evaluation and comparison of the effects of different nature NRs on conservation efforts are of great importance for protecting species diversity,ensuring reasonable national economic input,and adjusting government management schemes.Developing a method for the combined assessment of flagship or umbrella species and ecosystem quality will improve the evaluation of NRs.However,it is also important to establish a new framework for rapid evaluation of ecosystem quality,supported by the advantages of scientific,economic,and regular principles.Here,we proposed a new framework that incorporates the novel concept of ideal references into evaluation systems,which will facilitate the comparison of results from different periods and regions.Furthermore,from the perspective of making the framework as objective,rapid,and economical as possible,we recommended some key ecological indicators,such as net primary productivity,soil organic matter,plant diversity,for use in the new evaluation framework.The new framework,referred to as“ideal reference and key indicators”(IRKI),can sufficiently meet the requirements for the rapid evaluation of ecosystem quality both regionally and nationally.Furthermore,IRKI can identify the restoration potential and restoration periods of NRs,thus facilitating the rational distribution of resources and enhancing the protective effect.There are many types of NRs in China,and it is necessary to partially alter the assessment methods or parameters for different types of NRs.Overall,IRKI provides a simple,clear,and comparable framework that will strongly enhance the conservation of protected areas(PAs)and facilitate the standardization of management practices.