Three species of the genus Lista Walker are recognized from China, as a supplement of the former work. Among them, two species are described as new to science, namely L. furcillatusa Wang, Chen & Wu sp. nov. and L...Three species of the genus Lista Walker are recognized from China, as a supplement of the former work. Among them, two species are described as new to science, namely L. furcillatusa Wang, Chen & Wu sp. nov. and L. menglaensis Wang, Chen & Wu sp. nov. One species, L. monticola Yamanaka, 2000, is reported from China for the first time. Adults and genitalia of the three species are illustrated. Moreover, a key to the Chinese species and an updated checklist of the genus are provided.展开更多
Power system equipment outages are one of the most important factors affecting the reliability and economy of power systems.It is crucial to consider the reliability of the planning problems.In this paper,a generation...Power system equipment outages are one of the most important factors affecting the reliability and economy of power systems.It is crucial to consider the reliability of the planning problems.In this paper,a generation expansion planning(GEP)model is proposed,in which the candidate generating units and energy storage systems(ESSs)are simultaneously planned by minimizing the cost incurred on investment,operation,reserve,and reliability.The reliability cost is computed by multiplying the value of lost load(VOLL)with the expected energy not supplied(EENS),and this model makes a compromise between economy and reliability.Because the computation of EENS makes the major computation impediment of the entire model,a new efficient linear EENS formulation is proposed and applied in a multi-step GEP model.By doing so,the computation efficiency is significantly improved,and the solution accuracy is still desirable.The proposed GEP model is illustrated using the IEEE-RTS system to validate the effectiveness and superiority of the new model.展开更多
Uncertainty must be well addressed in transmission expansion planning(TEP)problem,and it significantly affects the reliability and cost-effectiveness of power systems.Owing to the complex operating environment of powe...Uncertainty must be well addressed in transmission expansion planning(TEP)problem,and it significantly affects the reliability and cost-effectiveness of power systems.Owing to the complex operating environment of power systems,it is crucial to consider different types of uncertainties during the planning stage.In this paper,a robust TEP model is proposed by considering multiple uncertainties and active load.Specifically,in this model,the uncertainties of wind power output and contingency probability are considered simultaneously.The uncertainties are described by scenario and interval,and the Benders decomposition technique is applied to solve the model.The feasibility and effectiveness of the proposed model are illustrated using the IEEE RTS and IEEE 118-node systems.展开更多
Three species of the genus Stericta are described as new to science, S. melasiversusa sp. nov., S. penicilasa sp. nov. and S. hampsoni sp. nov. And a new combination, Stericta melanobasis（Hampson, 1906） comb. nov., ...Three species of the genus Stericta are described as new to science, S. melasiversusa sp. nov., S. penicilasa sp. nov. and S. hampsoni sp. nov. And a new combination, Stericta melanobasis（Hampson, 1906） comb. nov., was transferred from the genus Lepidogma. All adults and their genital structures are illustrated. The differences between the genus Stericta and it allied genera are discussed.展开更多
Graphene is the most attractive carbon-based material at present and attracting increasing attention as promising candidates for applications in numerous areas, because of its extraordinary chemical, thermal and mecha...Graphene is the most attractive carbon-based material at present and attracting increasing attention as promising candidates for applications in numerous areas, because of its extraordinary chemical, thermal and mechanical properties. In this paper, we discussed an innovative and simple method to synthesize titanium dioxide （TiO2） nanoclusters, using graphene as a mid-step template not as a component of final product. Using this method, the graphene was firstly fully coated with TiO2 nanoparticles by the thermal decomposition of titanium （IV） isopropoxide in a supercritical carbon dioxide （SC-CO2） at 200 ℃; the developed TiO2/graphene composites then were heated in an oxygen atmosphere. Eventually the TiO2 nanoclusters were obtained. The prepared TiO2 nanoclusters showed irregular features with high surface coverage, providing promises in a wide range of applications, especially for photo-degradation of organic compounds in aqueous solution under the radiation of UV-light.展开更多
Epipaschiinae,a subfamily of Pyralidae,has characteristic features distinct from other groups of Pyralidae,such as the thick scales and labial palpi usually upturned.This subfamily is a relative smaller group in Pyral...Epipaschiinae,a subfamily of Pyralidae,has characteristic features distinct from other groups of Pyralidae,such as the thick scales and labial palpi usually upturned.This subfamily is a relative smaller group in Pyralidae,and currently reports over 700 species worldwide(Solis,1992,1994;Nuss et al.,2021).Solis(1992)listed 287 known epipaschiine species all over the world,including 273 species from Old World.In China,the first checklist of Epipaschiinae was systematically summarized by Lu and Guan(1953),including 8 genera and 53 species.展开更多
How many species of life are there on Earth?This is a question that we want to know but cannot yet answer.Some scholars speculate that the number of species may reach 2.2 billion when considering cryptic diversity and...How many species of life are there on Earth?This is a question that we want to know but cannot yet answer.Some scholars speculate that the number of species may reach 2.2 billion when considering cryptic diversity and that each morphology-based insect species may contain an average of 3.1 cryptic species.With nearly two million described species,such high estimates of cryptic diversity would suggest that cryptic species are widespread.The development of molecular species delimitation has led to the discovery of a large number of cryptic species,and cryptic biodiversity has gradually entered ourfield of vision and attracted more attention.This paper introduces the concept of cryptic species,how they evolve,and methods by which they may be discovered and confirmed,and provides theoretical and methodological guidance for the study of hidden species.A workflow of how to confirm cryptic species is provided.In addition,the importance and reliability of multi-evidence-based integrated taxonomy are reaffirmed as a way to better standardize decision-making processes.Special focus on cryptic diversity and increased funding for taxonomy is needed to ensure that cryptic species in hyperdiverse groups are discoverable and described.An increased focus on cryptic species in the future will naturally arise as more difficult groups are studied,and thereby,we mayfinally better understand the rules governing the evolution and maintenance of cryptic biodiversity.展开更多
This paper proposes a novel frequency aware robust economic dispatch (FARED) approach to exploit the synergistic capability of accommodating uncertain loads and renewable generation by accounting for both the frequenc...This paper proposes a novel frequency aware robust economic dispatch (FARED) approach to exploit the synergistic capability of accommodating uncertain loads and renewable generation by accounting for both the frequency regulation effect and optimal participation mechanism of secondary regulation reserves for conventional units in response to uncertainties in the robust optimization counterpart of security constrained economic dispatch.The FARED is formulated as a robust optimization problem.In this formulation the allowable frequency deviation and the possible load or renewable generation curtailments are expressed in terms of variable uncertainty sets.The variables in the formulation are described as interval variables and treated in affine form.In order to improve the computational tractability,the dominant constraints which canbe the candidates of tight transmission constraints are determined by complementarity constraints.Then the robust optimization problem is simplified to a bilinear programming problem based on duality theory.Finally,the effectiveness and efficiency of the proposed method are illustrated based on several study cases.展开更多
Si materials are widely considered to be the next-generation anode to replace the current commercial graphite-based anode due to its high energy density.However,the large volume variation of silicon during(de)lithiati...Si materials are widely considered to be the next-generation anode to replace the current commercial graphite-based anode due to its high energy density.However,the large volume variation of silicon during(de)lithiation process leads to rapid capacity decay,hindering its commercial application.Although the various hollow structure designs of Si nanomaterials have improved their cycling stability in the laboratory,the high-pressure calendering process in the current industrial electrode preparation process might collapse the hollow structure and weaken the structural advantages of hollow silicon anode materials.In this work,a silicon carbon composite material(Si@3DC)in which Si nanoparticles were anchored on a three-dimensional carbon framework through carbon films was prepared by a simple proton exchange method.The three-dimensional carbon framework with multiple hierarchical pores of Si@3DC was compatible with the high-pressure calendering process,but also could provide expansion space for Si nanoparticles during the lithiation process,and ensure good electronic and ionic conductivity.The carbon film on the surface of Si nanoparticles promoted the formation of stable solid electrolyte interphase(SEI)films,ensuring the good cycle stability of Si@3DC.展开更多
Demand response(DR) is important to account for behaviors of the demand side to yield an optimal dispatch result. However, it is difficult for energy suppliers to collect customers' private information unless ther...Demand response(DR) is important to account for behaviors of the demand side to yield an optimal dispatch result. However, it is difficult for energy suppliers to collect customers' private information unless there is an incentive mechanism for customers to do so. Therefore,this paper proposes a new integrated generation–consumption dispatch based on compensation mechanism considering DR behavior. Firstly, in light of the dayahead load forecast data, we deduce the utility function model of different customers. By subtracting generating units' operation cost from consumers' total utility, the dispatch model has a decentralized demand participant structure based on this utility function. The utility function is used to describe consumers' preferences and energy consumption behaviors. Secondly, an effective compensation mechanism is designed to ensure customers to select the level of compensation appropriate to their willingness to curtail load. Finally, a new dispatch model is proposed that incorporates the DR compensation mechanism into the generation–consumption dispatch model. The new model can improve the interaction of generation and consumption,and benefit both the energy supplier and its customers. The proposed model is piecewise linearized and solved by a mixed-integer linear programming method. It is tested on a six-bus system and the IEEE 118-bus system. Simulation results show that the proposed model can realize both maximum social welfare and Pareto optimal results.展开更多
Attribute-based encryption with keyword search(ABKS)achieves both fine-grained access control and keyword search.However,in the previous ABKS schemes,the search algorithm requires that each keyword to be identical bet...Attribute-based encryption with keyword search(ABKS)achieves both fine-grained access control and keyword search.However,in the previous ABKS schemes,the search algorithm requires that each keyword to be identical between the target keyword set and the ciphertext keyword set,otherwise the algorithm does not output any search result,which is not conducive to use.Moreover,the previous ABKS schemes are vulnerable to what we call a peer-decryption attack,that is,the ciphertext may be eavesdropped and decrypted by an adversary who has sufficient authorities but no information about the ciphertext keywords.In this paper,we provide a new system in fog computing,the ciphertext-policy attribute-based encryption with dynamic keyword search(ABDKS).In ABDKS,the search algorithm requires only one keyword to be identical between the two keyword sets and outputs the corresponding correlation which reflects the number of the same keywords in those two sets.In addition,our ABDKS is resistant to peer-decryption attack,since the decryption requires not only sufficient authority but also at least one keyword of the ciphertext.Beyond that,the ABDKS shifts most computational overheads from resource constrained users to fog nodes.The security analysis shows that the ABDKS can resist Chosen-Plaintext Attack(CPA)and Chosen-Keyword Attack(CKA).展开更多
The outage of power system equipment is one of the most important factors that affect the reliability and economy of power system.It is crucial to consider the influence of contingencies elaborately in planning proble...The outage of power system equipment is one of the most important factors that affect the reliability and economy of power system.It is crucial to consider the influence of contingencies elaborately in planning problem.In this paper,a distributionally robust transmission expansion planning model is proposed in which the uncertainty of contingency probability is considered.The uncertainty of contingency probability is described by uncertainty interval based on the outage rate of single equipment.An epigraph reformulation and Benders decomposition are applied to solve the proposed model.Finally,the feasibility and effectiveness of the proposed model are illustrated on the IEEE RTS system and the IEEE 118-bus system.展开更多
It is proved that for almost all sufficiently large even integers n,the prime variable equation n=p1+p2,p1∈Pγis solvable,with 13/15〈γ≤1,where Pγ={p|p=[m^1/γ],for integer m and prime p}is the set of the Piatetsk...It is proved that for almost all sufficiently large even integers n,the prime variable equation n=p1+p2,p1∈Pγis solvable,with 13/15〈γ≤1,where Pγ={p|p=[m^1/γ],for integer m and prime p}is the set of the Piatetski-Shapiro primes.展开更多
The operating conditions of wind turbines(WTs)in the same wind farm(WF)may share similarities due to their shared manufacturing process,control strategy,and operating environment.However,the similarities of WTs are se...The operating conditions of wind turbines(WTs)in the same wind farm(WF)may share similarities due to their shared manufacturing process,control strategy,and operating environment.However,the similarities of WTs are seldom considered in WT anomaly detection,resulting in the disregard of useful information.This paper proposes a method to improve the reliability and accuracy of WT anomaly detection using the supervisory control and data acquisition(SCADA)data of multiple WTs in the same WF.First,a similarity assessment method based on a comparison of different observation time series is proposed,which objectively quantifies the similarities of WT operating conditions.Then,the SCADA data of the target WT and selected WTs that are similar are used to establish several estimation models through a long short-term memory(LSTM)algorithm.LSTM models that exhibit good estimation performance are used to construct a combined estimation model that estimates the variations in the monitored variables of the target WT.Finally,an anomaly detection method that jointly compares the effective value and information entropy of the residuals is proposed to identify anomalies.The effectiveness and accuracy of the proposed method are verified using the data of two actual WFs.展开更多
The hardness of NTRU problem affects heavily on the securities of the cryptosystems based on it.However,we could only estimate the hardness of the specific parameterized NTRU problems from the perspective of actual at...The hardness of NTRU problem affects heavily on the securities of the cryptosystems based on it.However,we could only estimate the hardness of the specific parameterized NTRU problems from the perspective of actual attacks,and whether there are worst-case to average-case reductions for NTRU problems like other lattice-based problems(e.g.,the Ring-LWE problem)is still an open problem.In this paper,we show that for any algebraic number field K,the NTRU problem with suitable parameters defined over the ring of integers R is at least as hard as the corresponding Ring-LWE problem.Hence,combining known reductions of the Ring-LWE problem,we could reduce worst-case basic ideal lattice problems,e.g.,SIVPγproblem,to average-case NTRU problems.Our results also mean that solving a kind of average-case SVPγproblem over highly structured NTRU lattice is at least as hard as worst-case basic ideal lattice problems in K.As an important corollary,we could prove that for modulus q=Õ(n^(5.5)),average-case NTRU problem over arbitrary cyclotomic field K with[K:Q]=n is at least as hard as worst-case SIVP_(γ)problems over K with γ=Õ(n^(6)).展开更多
基金supported by the National Key R&D Program of China(2016YFE0203100)the National Natural Science Foundation of China(31772489,31750002)the grant(Y229YX5105)from Key Laboratory of Zoological Systematics and Evolution,Chinese Academy of Sciences
文摘Three species of the genus Lista Walker are recognized from China, as a supplement of the former work. Among them, two species are described as new to science, namely L. furcillatusa Wang, Chen & Wu sp. nov. and L. menglaensis Wang, Chen & Wu sp. nov. One species, L. monticola Yamanaka, 2000, is reported from China for the first time. Adults and genitalia of the three species are illustrated. Moreover, a key to the Chinese species and an updated checklist of the genus are provided.
基金supported by project of State Grid Shandong Electric Power Company(52062520000Q)the National Key Research and Development Program of China(2019YFE0118400)。
文摘Power system equipment outages are one of the most important factors affecting the reliability and economy of power systems.It is crucial to consider the reliability of the planning problems.In this paper,a generation expansion planning(GEP)model is proposed,in which the candidate generating units and energy storage systems(ESSs)are simultaneously planned by minimizing the cost incurred on investment,operation,reserve,and reliability.The reliability cost is computed by multiplying the value of lost load(VOLL)with the expected energy not supplied(EENS),and this model makes a compromise between economy and reliability.Because the computation of EENS makes the major computation impediment of the entire model,a new efficient linear EENS formulation is proposed and applied in a multi-step GEP model.By doing so,the computation efficiency is significantly improved,and the solution accuracy is still desirable.The proposed GEP model is illustrated using the IEEE-RTS system to validate the effectiveness and superiority of the new model.
基金supported by a project of the State Grid Shandong Electric Power Company(52062520000Q)the National Key Research and Development Program of China(2019YFE0118400).
文摘Uncertainty must be well addressed in transmission expansion planning(TEP)problem,and it significantly affects the reliability and cost-effectiveness of power systems.Owing to the complex operating environment of power systems,it is crucial to consider different types of uncertainties during the planning stage.In this paper,a robust TEP model is proposed by considering multiple uncertainties and active load.Specifically,in this model,the uncertainties of wind power output and contingency probability are considered simultaneously.The uncertainties are described by scenario and interval,and the Benders decomposition technique is applied to solve the model.The feasibility and effectiveness of the proposed model are illustrated using the IEEE RTS and IEEE 118-node systems.
基金supported by the National Natural Science Foundation of China(31471959,31750002)the National Basic Research Program of China(2014FY110100)
文摘Three species of the genus Stericta are described as new to science, S. melasiversusa sp. nov., S. penicilasa sp. nov. and S. hampsoni sp. nov. And a new combination, Stericta melanobasis（Hampson, 1906） comb. nov., was transferred from the genus Lepidogma. All adults and their genital structures are illustrated. The differences between the genus Stericta and it allied genera are discussed.
基金financial support from iNANO through the Danish National Research Foundationthe National Natural Science Foundation of China to the Sino-Danish Center of Excellence on"The Self-assembly and Function of Molecular Nanostructures on Surfaces"+6 种基金the Carlsberg Foundationthe Villum Foundationthe National Natural Science Foundation of China(No.51003021)China Postdoctoral Science Special Foundation(Nos.201003420 and20090460067)UTC Exploration Project(CASC-HIT12-1C03)Opening Project of Key Laboratory of Solid Waste Treatment and Resource Recycle,Ministry of Education(12zxgk10)Harbin City Science and Technology Projects(2013DB4BP031)
文摘Graphene is the most attractive carbon-based material at present and attracting increasing attention as promising candidates for applications in numerous areas, because of its extraordinary chemical, thermal and mechanical properties. In this paper, we discussed an innovative and simple method to synthesize titanium dioxide （TiO2） nanoclusters, using graphene as a mid-step template not as a component of final product. Using this method, the graphene was firstly fully coated with TiO2 nanoparticles by the thermal decomposition of titanium （IV） isopropoxide in a supercritical carbon dioxide （SC-CO2） at 200 ℃; the developed TiO2/graphene composites then were heated in an oxygen atmosphere. Eventually the TiO2 nanoclusters were obtained. The prepared TiO2 nanoclusters showed irregular features with high surface coverage, providing promises in a wide range of applications, especially for photo-degradation of organic compounds in aqueous solution under the radiation of UV-light.
基金supported by the National Natural Science Foundation of China(31772489)。
文摘Epipaschiinae,a subfamily of Pyralidae,has characteristic features distinct from other groups of Pyralidae,such as the thick scales and labial palpi usually upturned.This subfamily is a relative smaller group in Pyralidae,and currently reports over 700 species worldwide(Solis,1992,1994;Nuss et al.,2021).Solis(1992)listed 287 known epipaschiine species all over the world,including 273 species from Old World.In China,the first checklist of Epipaschiinae was systematically summarized by Lu and Guan(1953),including 8 genera and 53 species.
基金supported by the Ningxia Hui Autonomous Region Agricultural Science and Technology Independent Innovation Fund(NGSB20211405)Key Laboratory of the Zoological Systematics and Evolution of the Chinese Academy of Sciences(2008DP173354)the Survey of Wildlife Resources in Key Areas of Tibet(ZL202203601).
文摘How many species of life are there on Earth?This is a question that we want to know but cannot yet answer.Some scholars speculate that the number of species may reach 2.2 billion when considering cryptic diversity and that each morphology-based insect species may contain an average of 3.1 cryptic species.With nearly two million described species,such high estimates of cryptic diversity would suggest that cryptic species are widespread.The development of molecular species delimitation has led to the discovery of a large number of cryptic species,and cryptic biodiversity has gradually entered ourfield of vision and attracted more attention.This paper introduces the concept of cryptic species,how they evolve,and methods by which they may be discovered and confirmed,and provides theoretical and methodological guidance for the study of hidden species.A workflow of how to confirm cryptic species is provided.In addition,the importance and reliability of multi-evidence-based integrated taxonomy are reaffirmed as a way to better standardize decision-making processes.Special focus on cryptic diversity and increased funding for taxonomy is needed to ensure that cryptic species in hyperdiverse groups are discoverable and described.An increased focus on cryptic species in the future will naturally arise as more difficult groups are studied,and thereby,we mayfinally better understand the rules governing the evolution and maintenance of cryptic biodiversity.
基金supported by the National Basic Research Program of China (973 Program) (No.2013CB228205)the National Natural Science Foundation of China (No.51177091, No.51477091)
文摘This paper proposes a novel frequency aware robust economic dispatch (FARED) approach to exploit the synergistic capability of accommodating uncertain loads and renewable generation by accounting for both the frequency regulation effect and optimal participation mechanism of secondary regulation reserves for conventional units in response to uncertainties in the robust optimization counterpart of security constrained economic dispatch.The FARED is formulated as a robust optimization problem.In this formulation the allowable frequency deviation and the possible load or renewable generation curtailments are expressed in terms of variable uncertainty sets.The variables in the formulation are described as interval variables and treated in affine form.In order to improve the computational tractability,the dominant constraints which canbe the candidates of tight transmission constraints are determined by complementarity constraints.Then the robust optimization problem is simplified to a bilinear programming problem based on duality theory.Finally,the effectiveness and efficiency of the proposed method are illustrated based on several study cases.
基金supported financially by the National Key Research and Development Program of China(No.2017YFB0307701).
文摘Si materials are widely considered to be the next-generation anode to replace the current commercial graphite-based anode due to its high energy density.However,the large volume variation of silicon during(de)lithiation process leads to rapid capacity decay,hindering its commercial application.Although the various hollow structure designs of Si nanomaterials have improved their cycling stability in the laboratory,the high-pressure calendering process in the current industrial electrode preparation process might collapse the hollow structure and weaken the structural advantages of hollow silicon anode materials.In this work,a silicon carbon composite material(Si@3DC)in which Si nanoparticles were anchored on a three-dimensional carbon framework through carbon films was prepared by a simple proton exchange method.The three-dimensional carbon framework with multiple hierarchical pores of Si@3DC was compatible with the high-pressure calendering process,but also could provide expansion space for Si nanoparticles during the lithiation process,and ensure good electronic and ionic conductivity.The carbon film on the surface of Si nanoparticles promoted the formation of stable solid electrolyte interphase(SEI)films,ensuring the good cycle stability of Si@3DC.
基金supported by National Natural Science Foundation of China(No.51477091,No.51407106)
文摘Demand response(DR) is important to account for behaviors of the demand side to yield an optimal dispatch result. However, it is difficult for energy suppliers to collect customers' private information unless there is an incentive mechanism for customers to do so. Therefore,this paper proposes a new integrated generation–consumption dispatch based on compensation mechanism considering DR behavior. Firstly, in light of the dayahead load forecast data, we deduce the utility function model of different customers. By subtracting generating units' operation cost from consumers' total utility, the dispatch model has a decentralized demand participant structure based on this utility function. The utility function is used to describe consumers' preferences and energy consumption behaviors. Secondly, an effective compensation mechanism is designed to ensure customers to select the level of compensation appropriate to their willingness to curtail load. Finally, a new dispatch model is proposed that incorporates the DR compensation mechanism into the generation–consumption dispatch model. The new model can improve the interaction of generation and consumption,and benefit both the energy supplier and its customers. The proposed model is piecewise linearized and solved by a mixed-integer linear programming method. It is tested on a six-bus system and the IEEE 118-bus system. Simulation results show that the proposed model can realize both maximum social welfare and Pareto optimal results.
基金National Cryptography Development Fund(MMJJ20180210)the National Natural Science Foundation of China(Grant Nos.61832012 and 61672019).
文摘Attribute-based encryption with keyword search(ABKS)achieves both fine-grained access control and keyword search.However,in the previous ABKS schemes,the search algorithm requires that each keyword to be identical between the target keyword set and the ciphertext keyword set,otherwise the algorithm does not output any search result,which is not conducive to use.Moreover,the previous ABKS schemes are vulnerable to what we call a peer-decryption attack,that is,the ciphertext may be eavesdropped and decrypted by an adversary who has sufficient authorities but no information about the ciphertext keywords.In this paper,we provide a new system in fog computing,the ciphertext-policy attribute-based encryption with dynamic keyword search(ABDKS).In ABDKS,the search algorithm requires only one keyword to be identical between the two keyword sets and outputs the corresponding correlation which reflects the number of the same keywords in those two sets.In addition,our ABDKS is resistant to peer-decryption attack,since the decryption requires not only sufficient authority but also at least one keyword of the ciphertext.Beyond that,the ABDKS shifts most computational overheads from resource constrained users to fog nodes.The security analysis shows that the ABDKS can resist Chosen-Plaintext Attack(CPA)and Chosen-Keyword Attack(CKA).
文摘The outage of power system equipment is one of the most important factors that affect the reliability and economy of power system.It is crucial to consider the influence of contingencies elaborately in planning problem.In this paper,a distributionally robust transmission expansion planning model is proposed in which the uncertainty of contingency probability is considered.The uncertainty of contingency probability is described by uncertainty interval based on the outage rate of single equipment.An epigraph reformulation and Benders decomposition are applied to solve the proposed model.Finally,the feasibility and effectiveness of the proposed model are illustrated on the IEEE RTS system and the IEEE 118-bus system.
基金Project supported by the Foundation of Shandong Provincial Education Department in China(No.03F06)the Grant for Doctoral Fellows in Shandong Finance Institute
文摘It is proved that for almost all sufficiently large even integers n,the prime variable equation n=p1+p2,p1∈Pγis solvable,with 13/15〈γ≤1,where Pγ={p|p=[m^1/γ],for integer m and prime p}is the set of the Piatetski-Shapiro primes.
文摘The operating conditions of wind turbines(WTs)in the same wind farm(WF)may share similarities due to their shared manufacturing process,control strategy,and operating environment.However,the similarities of WTs are seldom considered in WT anomaly detection,resulting in the disregard of useful information.This paper proposes a method to improve the reliability and accuracy of WT anomaly detection using the supervisory control and data acquisition(SCADA)data of multiple WTs in the same WF.First,a similarity assessment method based on a comparison of different observation time series is proposed,which objectively quantifies the similarities of WT operating conditions.Then,the SCADA data of the target WT and selected WTs that are similar are used to establish several estimation models through a long short-term memory(LSTM)algorithm.LSTM models that exhibit good estimation performance are used to construct a combined estimation model that estimates the variations in the monitored variables of the target WT.Finally,an anomaly detection method that jointly compares the effective value and information entropy of the residuals is proposed to identify anomalies.The effectiveness and accuracy of the proposed method are verified using the data of two actual WFs.
基金supported by the National Key Research and Development Program of China (2018YFA0704702)the National Natural Science Foundation of China (Grant No.61832012).
文摘The hardness of NTRU problem affects heavily on the securities of the cryptosystems based on it.However,we could only estimate the hardness of the specific parameterized NTRU problems from the perspective of actual attacks,and whether there are worst-case to average-case reductions for NTRU problems like other lattice-based problems(e.g.,the Ring-LWE problem)is still an open problem.In this paper,we show that for any algebraic number field K,the NTRU problem with suitable parameters defined over the ring of integers R is at least as hard as the corresponding Ring-LWE problem.Hence,combining known reductions of the Ring-LWE problem,we could reduce worst-case basic ideal lattice problems,e.g.,SIVPγproblem,to average-case NTRU problems.Our results also mean that solving a kind of average-case SVPγproblem over highly structured NTRU lattice is at least as hard as worst-case basic ideal lattice problems in K.As an important corollary,we could prove that for modulus q=Õ(n^(5.5)),average-case NTRU problem over arbitrary cyclotomic field K with[K:Q]=n is at least as hard as worst-case SIVP_(γ)problems over K with γ=Õ(n^(6)).
