Intelligent electronic devices(IEDs)are interconnected via communication networks and play pivotal roles in transmitting grid-related operational data and executing control instructions.In the context of the heightene...Intelligent electronic devices(IEDs)are interconnected via communication networks and play pivotal roles in transmitting grid-related operational data and executing control instructions.In the context of the heightened security challenges within smart grids,IEDs pose significant risks due to inherent hardware and software vulner-abilities,as well as the openness and vulnerability of communication protocols.Smart grid security,distinct from traditional internet security,mainly relies on monitoring network security events at the platform layer,lacking an effective assessment mechanism for IEDs.Hence,we incorporate considerations for both cyber-attacks and physical faults,presenting security assessment indicators and methods specifically tailored for IEDs.Initially,we outline the security monitoring technology for IEDs,considering the necessary data sources for their security assessment.Subsequently,we classify IEDs and establish a comprehensive security monitoring index system,incorporating factors such as running states,network traffic,and abnormal behaviors.This index system contains 18 indicators in 3 categories.Additionally,we elucidate quantitative methods for various indicators and propose a hybrid security assessment method known as GRCW-hybrid,combining grey relational analysis(GRA),analytic hierarchy process(AHP),and entropy weight method(EWM).According to the proposed assessment method,the security risk level of IEDs can be graded into 6 levels,namely 0,1,2,3,4,and 5.The higher the level,the greater the security risk.Finally,we assess and simulate 15 scenarios in 3 categories,which are based on monitoring indicators and real-world situations encountered by IEDs.The results show that calculated security risk level based on the proposed assessment method are consistent with actual simulation.Thus,the reasonableness and effectiveness of the proposed index system and assessment method are validated.展开更多
The remaining useful life(RUL) prediction of mechanical products has been widely studied for online system performance reliability, device remanufacturing, and product safety(safety awareness and safety improvement). ...The remaining useful life(RUL) prediction of mechanical products has been widely studied for online system performance reliability, device remanufacturing, and product safety(safety awareness and safety improvement). These studies incorporated many di erent models, algorithms, and techniques for modeling and assessment. In this paper, methods of RUL assessment are summarized and expounded upon using two major methods: physics model based and data driven based methods. The advantages and disadvantages of each of these methods are deliberated and compared as well. Due to the intricacy of failure mechanism in system, and di culty in physics degradation observation, RUL assessment based on observations of performance variables turns into a science in evaluating the degradation. A modeling method from control systems, the state space model(SSM), as a first order hidden Markov, is presented. In the context of non-linear and non-Gaussian systems, the SSM methodology is capable of performing remaining life assessment by using Bayesian estimation(sequential Monte Carlo). Being e ective for non-linear and non-Gaussian dynamics, the methodology can perform the assessment recursively online for applications in CBM(condition based maintenance), PHM(prognostics and health management), remanufacturing, and system performance reliability. Finally, the discussion raises concerns regarding online sensing data for SSM modeling and assessment of RUL.展开更多
AIM To explore the agreement between the mini-mental state examination(MMSE) and montreal cognitive assessment(Mo CA) within community dwelling older patients attending an old age psychiatry service and to derive and ...AIM To explore the agreement between the mini-mental state examination(MMSE) and montreal cognitive assessment(Mo CA) within community dwelling older patients attending an old age psychiatry service and to derive and test a conversion formula between the two scales.METHODS Prospective study of consecutive patients attending outpatient services.Both tests were administered by the same researcher on the same day in random order.RESULTS The total sample(n = 135) was randomly divided into two groups.One to derive a conversion rule(n = 70),and a second(n = 65) in which this rule was tested.The agreement(Pearson's r) of MMSE and Mo CA was 0.86(P < 0.001),and Lin's concordance correlation coefficient(CCC) was 0.57(95%CI:0.45-0.66).In the second sample Mo CA scores were converted to MMSE scores according to a conversion rule from the first sample which achieved agreement with the original MMSE scoresof 0.89(Pearson's r,P < 0.001) and CCC of 0.88(95%CI:0.82-0.92).CONCLUSION Although the two scales overlap considerably,the agreement is modest.The conversion rule derived herein demonstrated promising accuracy and warrants further testing in other populations.展开更多
The achievement progresses of investigation and studies on marine hazardous geology are summarized and presentsd in the late 20 century in China. The importance, research value and present-day studies of marine hazard...The achievement progresses of investigation and studies on marine hazardous geology are summarized and presentsd in the late 20 century in China. The importance, research value and present-day studies of marine hazardous geology, a newly developing branch of geoscience, are well expatiated. Several often confused concepts and theories are explained and redefined here. The comment on the means of investigations, assessment of marine hazardous geology, as well as its evolution, innovation, existing questions and future tasks are also introduced and presented. The concepts of 'hazard geology', geohazard', 'map of marine hazard geology', 'integrated evaluaton on seafloor stablity' are respectively discussed, including their definition, research objects, methods and contents. The types and classification of marine hazardous geology, principles and methods of marine hazardous geology map compilation, the assessment methods and models of marine hazardous geology environment and seafloor stability and so on are also discussed.展开更多
With the acceleration of the construction of quantum communication networks,scholars have proposed different quantum communication protocols for different application scenarios.However,few scholars pay attention to th...With the acceleration of the construction of quantum communication networks,scholars have proposed different quantum communication protocols for different application scenarios.However,few scholars pay attention to the risk assessment process before communication.In this paper,we propose a novel quantum risk assessment model based on quantum teleportation technology with two three-qubit GHZ states.Only by using Bell states measurements(BSMs)and two-qubit projective measurements(PJMs),the communicators can recovery any arbitrary two-qubit state.This protocol can transmit two-dimension risk assessment factors with better security performance.On the one hand,more sufficient evaluation factors allow the two communicating parties to more objectively evaluate the risk level of communication with the other party,and on the other hand,it also improves the qubit efficiency of the protocol.Moreover,we introduce the third party in this scheme can be semi-trusted,which must be full-trusted in our previous work.This change can reduce the dependence of the communication parties on the third-party organization and improve the privacy of communication.The security analysis shows that this scheme can resist internal and external attacks,and the quantum circuit diagrams also prove that our protocol is physically easier to implement.展开更多
Due to continuing aging and heavy utilization of many bridges and the limited available funds, the importance of proper bridge condition state assessment has risen recently, which is the crucial point for rational dec...Due to continuing aging and heavy utilization of many bridges and the limited available funds, the importance of proper bridge condition state assessment has risen recently, which is the crucial point for rational decision-making on MR&R activities. This paper presents a prototype of the concrete bridge condition state assessment system (CBCSAS) with the following sub-modules: inspection, parameter recognition, structural assessment, main cause identification and priority-to-action. And multi-layer neural networks, which may combine with fuzzy set theory or not, are performed to realize the structural assessment with embedding expert knowledge into the assessment system.展开更多
Wave energy resources assessment is a very important process before the exploitation and utilization of the wave energy. At present, the existing wave energy assessment is focused on theoretical wave energy conditions...Wave energy resources assessment is a very important process before the exploitation and utilization of the wave energy. At present, the existing wave energy assessment is focused on theoretical wave energy conditions for interesting areas. While the evaluation for exploitable wave energy conditions is scarcely ever performed. Generally speaking, the wave energy are non-exploitable under a high sea state and a lower sea state which must be ignored when assessing wave energy. Aiming at this situation, a case study of the East China Sea and the South China Sea is performed. First, a division basis between the theoretical wave energy and the exploitable wave energy is studied. Next, based on recent 20 a ERA-Interim wave field data, some indexes including the spatial and temporal distribution of wave power density, a wave energy exploitable ratio, a wave energy level, a wave energy stability, a total wave energy density, the seasonal variation of the total wave energy and a high sea condition frequency are calculated. And then the theoretical wave energy and the exploitable wave energy are compared each other; the distributions of the exploitable wave energy are assessed and a regional division for exploitable wave energy resources is carried out; the influence of the high sea state is evaluated. The results show that considering collapsing force of the high sea state and the utilization efficiency for wave energy, it is determined that the energy by wave with a significant wave height being not less 1 m or not greater than 4 m is the exploitable wave energy. Compared with the theoretical wave energy, the average wave power density, energy level, total wave energy density and total wave energy of the exploitable wave energy decrease obviously and the stability enhances somewhat. Pronounced differences between the theoretical wave energy and the exploitable wave energy are present. In the East China Sea and the South China Sea, the areas of an abundant and stable exploitable wave energy are primarily located in the north-central part of the South China Sea, the Luzon Strait, east of Taiwan, China and north of Ryukyu Islands; annual average exploitable wave power density values in these areas are approximately 10-15 kW/m; the exploitable coefficient of variation (COV) and seasonal variation (SV) values in these areas are less than 1.2 and 1, respectively. Some coastal areas of the Beibu Gulf, the Changjiang Estuary, the Hangzhou Bay and the Zhujiang Estuary are the poor areas of the wave energy. The areas of the high wave energy exploitable ratio is primarily in nearshore waters. The influence of the high sea state for the wave energy in nearshore waters is less than that in offshore waters. In the areas of the abundant wave energy, the influence of the high sea state for the wave energy is prominent and the utilization of wave energy is relatively difficult. The developed evaluation method may give some references for an exploitable wave energy assessment and is valuable for practical applications.展开更多
This study focused on a multi-indicator assessment methodology for governmental environmental auditing of water protection programs. The environmental status of Wuli Lake in China was assessed using the global indicat...This study focused on a multi-indicator assessment methodology for governmental environmental auditing of water protection programs. The environmental status of Wuli Lake in China was assessed using the global indicators (driver-status-response) developed by the Commission on Sustainable Development, and four additional indicators proposed by the author: water quality, pollution load, aquatic ecosystem status, and lake sediment deposition. Various hydrological, chemical, biological and environmental parameters were used to estimate the values of the indicators for assessment of environmental status of the lake based on time series data sets for twenty years. The indicators proposed can be customized to meeting the needs for particular assessment of water protection programs. This method can be used to evaluate the performance of national environmental protection programs and provide technical support for environmental auditors.展开更多
Computer networks face a variety of cyberattacks.Most network attacks are contagious and destructive,and these types of attacks can be harmful to society and computer network security.Security evaluation is an effecti...Computer networks face a variety of cyberattacks.Most network attacks are contagious and destructive,and these types of attacks can be harmful to society and computer network security.Security evaluation is an effective method to solve network security problems.For accurate assessment of the vulnerabilities of computer networks,this paper proposes a network security risk assessment method based on a Bayesian network attack graph(B_NAG)model.First,a new resource attack graph(RAG)and the algorithm E-Loop,which is applied to eliminate loops in the B_NAG,are proposed.Second,to distinguish the confusing relationships between nodes of the attack graph in the conversion process,a related algorithm is proposed to generate the B_NAG model.Finally,to analyze the reachability of paths in B_NAG,the measuring indexs such as node attack complexity and node state transition are defined,and an iterative algorithm for obtaining the probability of reaching the target node is presented.On this basis,the posterior probability of related nodes can be calculated.A simulation environment is set up to evaluate the effectiveness of the B_NAG model.The experimental results indicate that the B_NAG model is realistic and effective in evaluating vulnerabilities of computer networks and can accurately highlight the degree of vulnerability in a chaotic relationship.展开更多
Failure mechanisms of power transformers are complex and uncertain; it is difficult to determine index weights of insulation state. Therefore, it is a challenge to acquire an accurate assessment of insulation state of...Failure mechanisms of power transformers are complex and uncertain; it is difficult to determine index weights of insulation state. Therefore, it is a challenge to acquire an accurate assessment of insulation state of power transformers. In this paper, an assessing strategy for transformer insulation is proposed base on part-division of transformer and a comprehensive weight determination method. An index system of transformer is established on the basis of part-division of transformer. Each index’s weight is consisted of two parts, the constant weight and the variable weight, which are determined by improved analytic hierarchy process (AHP) and entropy method respectively. Af- ter categorizing insulation state into four levels and standardizing assessing indexes, a Cauchy membership function is forged, and a fuzzy algorithm is employed to simulate the uncertainty of the insulation state. Finally, a confidence criterion is employed to perform part-division based condition assessment of transformer. Case studies reveal that the proposed assessing strategy method is effective, convenient, and practical; with the new strategy, potential failures of transformers can be forecasted and insulation state of transformer parts can also be as- sessed. Furthermore, the assessing results can be used to guide condition-based maintenance.展开更多
Background: Worldwide elderly population and their life expectancy are increasing gradually. Longevity in most cases brings down poorer health as well as functional status. Thus, it is necessary to understand the prob...Background: Worldwide elderly population and their life expectancy are increasing gradually. Longevity in most cases brings down poorer health as well as functional status. Thus, it is necessary to understand the problems as well as social, psychological, and medical needs of elderly people in order to plan their optimal care. Objectives: To assess the mental health status (depression and memory state) of elderly people attending Geriatric clinic in medical city, and to determine the influence of some sociodemographic factors on elderly mental health status. Subjects and Method: A cross-sectional study was conducted among elderly people aged 60 years and more who attended geriatric clinic of medical city in Baghdad, from 1st of April to the end of June 2015. Special questionnaire form had been used for data collection via direct interview. The evaluation of the mental state was performed by using modified version of Wechsler Memory Scale and geriatric depression scale. Results: A total of 400 elderly persons were enrolled in the study, 109 (27.3%) of them had impaired memory. The analysis of data revealed that the age and marital status had statistical significant association with memory state. Nearly three quarter (72.8%) of study group had depression according to geriatric depression scale. The majority of studied women had depression (90%), and the same percentage was observed among widowed elders joining in the study.展开更多
Cognitive decline in Parkinson’s disease (PD) is defined as dementia which affects activities of daily living (ADL) function. Dementia is one of the recognized issues in the treatment of Parkinson’s disease patients...Cognitive decline in Parkinson’s disease (PD) is defined as dementia which affects activities of daily living (ADL) function. Dementia is one of the recognized issues in the treatment of Parkinson’s disease patients (PDP) as it is becoming a major contributor to morbidity. The objective of our study was to evaluate the cognitive decline in Parkinson’s disease patients (PDP) and the influence of cognition on daily living function deterioration in cognitively impaired and cognitively unimpaired PDP. Cognitively impaired PDP (n = 24), and cognitively unimpaired PDP (n = 16) were administered MoCA and MMSE performance based tests for cognitive measurements and Alzheimer’s Disease Cooperative Study Activities of Daily Living Inventory (ADCS-ADL) to determine everyday functioning. The significances of MoCA and MMSE among cognitively impaired PDP and cognitively unimpaired PDP in univariant analysis were P < 0.001 and P < 0.05. In partial correlation, MoCA was strongly related to ADL function as compare to MMSE (r = 0.623, P = 0.001). Cognitively impaired PDP showed significantly lower score on visuo-construction and attention. Among all variables of MoCA domains, attention is strongly associated with instrumental activity daily living (IADL) scores (logistic regression coefficient = 0.672, P = 0.01). These results suggest that dementia affects daily living performances especially the IADL tasks like attention and execution. Therefore, the assessment of complex daily activities particularly IADL is probably useful for the diagnosis of early stage cognitive impairment in PDP. Further MMSE test is less sensitive than MoCA for detecting significant cognitive decline in PDP and impaired attention is an important determinant of ADL functions in cognitively impaired PDP.展开更多
Due to the increasingly serious environmental pollution and destruction,especially humans' unreasonable activities,the ecological and economic system(EES) issues of Northwest region in China have attracted more an...Due to the increasingly serious environmental pollution and destruction,especially humans' unreasonable activities,the ecological and economic system(EES) issues of Northwest region in China have attracted more and more attention of the researchers.Aiming at evaluating its ecological and economic system health,a multi-objective evaluation framework called PressureState-Response(PSR) was established to describe the ecological and economic health situations.Meanwhile,an integrative set pair model combining set pair analysis(SPA) and fuzzy analytic hierarchy process(FAHP) was proposed to assess the ecological and economic system.Then the EES status of five northwest provinces(Shanxi,Gansu,Qinghai,Ningxia and Xinjiang) of Northwest region in China was evaluated during 1985 to 2009.The EES development trends of five provinces are obtained.In general,the health values of five provinces showed a rising trend.The health values of five provinces grew rapidly during 1985 to 2000.After 2000,the health values of five provinces still followed the present growth trend,but the growth is relatively smooth.The results show that the method proposed is effective for assessing the health of ecological and economic system.展开更多
This paper presents a new method of damage condition assessment that allows accommodating other types of uncertainties due to ambiguity, vagueness, and fuzziness that are statistically nondescribable. In this method, ...This paper presents a new method of damage condition assessment that allows accommodating other types of uncertainties due to ambiguity, vagueness, and fuzziness that are statistically nondescribable. In this method, healthy observations are used to construct a fury set representing sound performance characteristics. Additionally, the bounds on the similarities among the structural damage states are prescribed by using the state similarity matrix. Thus, an optimal group fuzzy sets representing damage states such as little, moderate, and severe damage can be inferred as an inverse problem from healthy observations only. The optimal group of damage fuzzy sets is used to classify a set of observations at any unknown state of damage using the principles of fitzzy pattern recognition based on an approximate principle . This method can be embedded into the system of Structural Health Monitoring (SHM) to give advice about structural maintenance and life predictio comes from Reference [ 9 ] for damage pattern recognition is presented n. Finally, a case and discussed. The study, which compared result illustrates our method is more effective and general, so it is very practical in engineering.展开更多
Using the method of trophic state-composite index (TSI-CI ) and the 12 months of monitoring data in 2010,we carry out initial exploration of the status of ecosystem health in Wuli Lake. First,we select four indicators...Using the method of trophic state-composite index (TSI-CI ) and the 12 months of monitoring data in 2010,we carry out initial exploration of the status of ecosystem health in Wuli Lake. First,we select four indicators,Chla,SD,TP and TN,to conduct trophic state assessment using weighted index method; then after selecting physical,chemical and biological indicators to conduct nondimensionalization processing,we calculate the composite index and conduct comprehensive assessment. The results show that in 2010,the status of ecosystem health in Wuli Lake was the best in July,worst in August; when the composite trophic state indicators with Chla as the representative increase or decrease significantly and cross different nutritional grades,TSI will significantly deviate from CI,and the relationship between the two in the other time is not prominent.展开更多
保护状况评估(State of Conservation,SOC)是世界遗产的评估管理环节,目的是持续掌握遗产所面临的各类威胁。文章解读世界遗产SOC评估机制及其发展、完善过程,分析其影响因素指标体系,并结合世界遗产的典型案例,阐释SOC评估在世界遗产...保护状况评估(State of Conservation,SOC)是世界遗产的评估管理环节,目的是持续掌握遗产所面临的各类威胁。文章解读世界遗产SOC评估机制及其发展、完善过程,分析其影响因素指标体系,并结合世界遗产的典型案例,阐释SOC评估在世界遗产保护管理实践中的应用和实效。建议在我国城乡文化遗产保护管理中,建立影响因素评估标准化指标体系以及有效的跟踪和退出机制,以维护文化遗产的价值和遗产名录的可信度,使有限的保护资源得以集中利用。展开更多
基金The financial support from the Program for Science and Technology of Henan Province of China(Grant No.242102210148)Henan Center for Outstanding Overseas Scientists(Grant No.GZS2022011)Songshan Laboratory Pre-Research Project(Grant No.YYJC032022022).
文摘Intelligent electronic devices(IEDs)are interconnected via communication networks and play pivotal roles in transmitting grid-related operational data and executing control instructions.In the context of the heightened security challenges within smart grids,IEDs pose significant risks due to inherent hardware and software vulner-abilities,as well as the openness and vulnerability of communication protocols.Smart grid security,distinct from traditional internet security,mainly relies on monitoring network security events at the platform layer,lacking an effective assessment mechanism for IEDs.Hence,we incorporate considerations for both cyber-attacks and physical faults,presenting security assessment indicators and methods specifically tailored for IEDs.Initially,we outline the security monitoring technology for IEDs,considering the necessary data sources for their security assessment.Subsequently,we classify IEDs and establish a comprehensive security monitoring index system,incorporating factors such as running states,network traffic,and abnormal behaviors.This index system contains 18 indicators in 3 categories.Additionally,we elucidate quantitative methods for various indicators and propose a hybrid security assessment method known as GRCW-hybrid,combining grey relational analysis(GRA),analytic hierarchy process(AHP),and entropy weight method(EWM).According to the proposed assessment method,the security risk level of IEDs can be graded into 6 levels,namely 0,1,2,3,4,and 5.The higher the level,the greater the security risk.Finally,we assess and simulate 15 scenarios in 3 categories,which are based on monitoring indicators and real-world situations encountered by IEDs.The results show that calculated security risk level based on the proposed assessment method are consistent with actual simulation.Thus,the reasonableness and effectiveness of the proposed index system and assessment method are validated.
基金Supported by Fundamental Research Funds for the Central Universities of China(Grant No.DUT17GF214)
文摘The remaining useful life(RUL) prediction of mechanical products has been widely studied for online system performance reliability, device remanufacturing, and product safety(safety awareness and safety improvement). These studies incorporated many di erent models, algorithms, and techniques for modeling and assessment. In this paper, methods of RUL assessment are summarized and expounded upon using two major methods: physics model based and data driven based methods. The advantages and disadvantages of each of these methods are deliberated and compared as well. Due to the intricacy of failure mechanism in system, and di culty in physics degradation observation, RUL assessment based on observations of performance variables turns into a science in evaluating the degradation. A modeling method from control systems, the state space model(SSM), as a first order hidden Markov, is presented. In the context of non-linear and non-Gaussian systems, the SSM methodology is capable of performing remaining life assessment by using Bayesian estimation(sequential Monte Carlo). Being e ective for non-linear and non-Gaussian dynamics, the methodology can perform the assessment recursively online for applications in CBM(condition based maintenance), PHM(prognostics and health management), remanufacturing, and system performance reliability. Finally, the discussion raises concerns regarding online sensing data for SSM modeling and assessment of RUL.
文摘AIM To explore the agreement between the mini-mental state examination(MMSE) and montreal cognitive assessment(Mo CA) within community dwelling older patients attending an old age psychiatry service and to derive and test a conversion formula between the two scales.METHODS Prospective study of consecutive patients attending outpatient services.Both tests were administered by the same researcher on the same day in random order.RESULTS The total sample(n = 135) was randomly divided into two groups.One to derive a conversion rule(n = 70),and a second(n = 65) in which this rule was tested.The agreement(Pearson's r) of MMSE and Mo CA was 0.86(P < 0.001),and Lin's concordance correlation coefficient(CCC) was 0.57(95%CI:0.45-0.66).In the second sample Mo CA scores were converted to MMSE scores according to a conversion rule from the first sample which achieved agreement with the original MMSE scoresof 0.89(Pearson's r,P < 0.001) and CCC of 0.88(95%CI:0.82-0.92).CONCLUSION Although the two scales overlap considerably,the agreement is modest.The conversion rule derived herein demonstrated promising accuracy and warrants further testing in other populations.
文摘The achievement progresses of investigation and studies on marine hazardous geology are summarized and presentsd in the late 20 century in China. The importance, research value and present-day studies of marine hazardous geology, a newly developing branch of geoscience, are well expatiated. Several often confused concepts and theories are explained and redefined here. The comment on the means of investigations, assessment of marine hazardous geology, as well as its evolution, innovation, existing questions and future tasks are also introduced and presented. The concepts of 'hazard geology', geohazard', 'map of marine hazard geology', 'integrated evaluaton on seafloor stablity' are respectively discussed, including their definition, research objects, methods and contents. The types and classification of marine hazardous geology, principles and methods of marine hazardous geology map compilation, the assessment methods and models of marine hazardous geology environment and seafloor stability and so on are also discussed.
基金This work is supported by the National Natural Science Foundation of China(No.61572086,No.61402058)the Key Research and Development Project of Sichuan Province(No.20ZDYF2324,No.2019ZYD027,No.2018TJPT0012)+3 种基金the Innovation Team of Quantum Security Communication of Sichuan Province(No.17TD0009)the Academic and Technical Leaders Training Funding Support Projects of Sichuan Province(No.2016120080102643)the Application Foundation Project of Sichuan Province(No.2017JY0168)the Science and Technology Support Project of Sichuan Province(No.2018GZ0204,No.2016FZ0112).
文摘With the acceleration of the construction of quantum communication networks,scholars have proposed different quantum communication protocols for different application scenarios.However,few scholars pay attention to the risk assessment process before communication.In this paper,we propose a novel quantum risk assessment model based on quantum teleportation technology with two three-qubit GHZ states.Only by using Bell states measurements(BSMs)and two-qubit projective measurements(PJMs),the communicators can recovery any arbitrary two-qubit state.This protocol can transmit two-dimension risk assessment factors with better security performance.On the one hand,more sufficient evaluation factors allow the two communicating parties to more objectively evaluate the risk level of communication with the other party,and on the other hand,it also improves the qubit efficiency of the protocol.Moreover,we introduce the third party in this scheme can be semi-trusted,which must be full-trusted in our previous work.This change can reduce the dependence of the communication parties on the third-party organization and improve the privacy of communication.The security analysis shows that this scheme can resist internal and external attacks,and the quantum circuit diagrams also prove that our protocol is physically easier to implement.
文摘Due to continuing aging and heavy utilization of many bridges and the limited available funds, the importance of proper bridge condition state assessment has risen recently, which is the crucial point for rational decision-making on MR&R activities. This paper presents a prototype of the concrete bridge condition state assessment system (CBCSAS) with the following sub-modules: inspection, parameter recognition, structural assessment, main cause identification and priority-to-action. And multi-layer neural networks, which may combine with fuzzy set theory or not, are performed to realize the structural assessment with embedding expert knowledge into the assessment system.
基金The Dragon III Project of the European Space Agency and Ministry of Science and Technology of China under contract No.10412the Ocean Renewable Energy Special Fund Project of State Oceanic Administration of China under contract No.GHME2011ZC07the National Natural Science Foundation of China(NSFC)under contract No.41176157
文摘Wave energy resources assessment is a very important process before the exploitation and utilization of the wave energy. At present, the existing wave energy assessment is focused on theoretical wave energy conditions for interesting areas. While the evaluation for exploitable wave energy conditions is scarcely ever performed. Generally speaking, the wave energy are non-exploitable under a high sea state and a lower sea state which must be ignored when assessing wave energy. Aiming at this situation, a case study of the East China Sea and the South China Sea is performed. First, a division basis between the theoretical wave energy and the exploitable wave energy is studied. Next, based on recent 20 a ERA-Interim wave field data, some indexes including the spatial and temporal distribution of wave power density, a wave energy exploitable ratio, a wave energy level, a wave energy stability, a total wave energy density, the seasonal variation of the total wave energy and a high sea condition frequency are calculated. And then the theoretical wave energy and the exploitable wave energy are compared each other; the distributions of the exploitable wave energy are assessed and a regional division for exploitable wave energy resources is carried out; the influence of the high sea state is evaluated. The results show that considering collapsing force of the high sea state and the utilization efficiency for wave energy, it is determined that the energy by wave with a significant wave height being not less 1 m or not greater than 4 m is the exploitable wave energy. Compared with the theoretical wave energy, the average wave power density, energy level, total wave energy density and total wave energy of the exploitable wave energy decrease obviously and the stability enhances somewhat. Pronounced differences between the theoretical wave energy and the exploitable wave energy are present. In the East China Sea and the South China Sea, the areas of an abundant and stable exploitable wave energy are primarily located in the north-central part of the South China Sea, the Luzon Strait, east of Taiwan, China and north of Ryukyu Islands; annual average exploitable wave power density values in these areas are approximately 10-15 kW/m; the exploitable coefficient of variation (COV) and seasonal variation (SV) values in these areas are less than 1.2 and 1, respectively. Some coastal areas of the Beibu Gulf, the Changjiang Estuary, the Hangzhou Bay and the Zhujiang Estuary are the poor areas of the wave energy. The areas of the high wave energy exploitable ratio is primarily in nearshore waters. The influence of the high sea state for the wave energy in nearshore waters is less than that in offshore waters. In the areas of the abundant wave energy, the influence of the high sea state for the wave energy is prominent and the utilization of wave energy is relatively difficult. The developed evaluation method may give some references for an exploitable wave energy assessment and is valuable for practical applications.
基金Project supported by the International Project between The Netherlands Royal Academy of Arts and Sciences and Chinese Academy of Sciences (No. 04CDP014) the National Natural Science Foundation of China (No. 40471130)
文摘This study focused on a multi-indicator assessment methodology for governmental environmental auditing of water protection programs. The environmental status of Wuli Lake in China was assessed using the global indicators (driver-status-response) developed by the Commission on Sustainable Development, and four additional indicators proposed by the author: water quality, pollution load, aquatic ecosystem status, and lake sediment deposition. Various hydrological, chemical, biological and environmental parameters were used to estimate the values of the indicators for assessment of environmental status of the lake based on time series data sets for twenty years. The indicators proposed can be customized to meeting the needs for particular assessment of water protection programs. This method can be used to evaluate the performance of national environmental protection programs and provide technical support for environmental auditors.
基金This work was partially supported by the National Natural Science Foundation of China(61300216,Wang,H,www.nsfc.gov.cn).
文摘Computer networks face a variety of cyberattacks.Most network attacks are contagious and destructive,and these types of attacks can be harmful to society and computer network security.Security evaluation is an effective method to solve network security problems.For accurate assessment of the vulnerabilities of computer networks,this paper proposes a network security risk assessment method based on a Bayesian network attack graph(B_NAG)model.First,a new resource attack graph(RAG)and the algorithm E-Loop,which is applied to eliminate loops in the B_NAG,are proposed.Second,to distinguish the confusing relationships between nodes of the attack graph in the conversion process,a related algorithm is proposed to generate the B_NAG model.Finally,to analyze the reachability of paths in B_NAG,the measuring indexs such as node attack complexity and node state transition are defined,and an iterative algorithm for obtaining the probability of reaching the target node is presented.On this basis,the posterior probability of related nodes can be calculated.A simulation environment is set up to evaluate the effectiveness of the B_NAG model.The experimental results indicate that the B_NAG model is realistic and effective in evaluating vulnerabilities of computer networks and can accurately highlight the degree of vulnerability in a chaotic relationship.
基金Project supported by Fund for Innovative Research Groups of China (51021005)Fundamental Research Fund for the Central Universities of China(CDJRC10150004)
文摘Failure mechanisms of power transformers are complex and uncertain; it is difficult to determine index weights of insulation state. Therefore, it is a challenge to acquire an accurate assessment of insulation state of power transformers. In this paper, an assessing strategy for transformer insulation is proposed base on part-division of transformer and a comprehensive weight determination method. An index system of transformer is established on the basis of part-division of transformer. Each index’s weight is consisted of two parts, the constant weight and the variable weight, which are determined by improved analytic hierarchy process (AHP) and entropy method respectively. Af- ter categorizing insulation state into four levels and standardizing assessing indexes, a Cauchy membership function is forged, and a fuzzy algorithm is employed to simulate the uncertainty of the insulation state. Finally, a confidence criterion is employed to perform part-division based condition assessment of transformer. Case studies reveal that the proposed assessing strategy method is effective, convenient, and practical; with the new strategy, potential failures of transformers can be forecasted and insulation state of transformer parts can also be as- sessed. Furthermore, the assessing results can be used to guide condition-based maintenance.
文摘Background: Worldwide elderly population and their life expectancy are increasing gradually. Longevity in most cases brings down poorer health as well as functional status. Thus, it is necessary to understand the problems as well as social, psychological, and medical needs of elderly people in order to plan their optimal care. Objectives: To assess the mental health status (depression and memory state) of elderly people attending Geriatric clinic in medical city, and to determine the influence of some sociodemographic factors on elderly mental health status. Subjects and Method: A cross-sectional study was conducted among elderly people aged 60 years and more who attended geriatric clinic of medical city in Baghdad, from 1st of April to the end of June 2015. Special questionnaire form had been used for data collection via direct interview. The evaluation of the mental state was performed by using modified version of Wechsler Memory Scale and geriatric depression scale. Results: A total of 400 elderly persons were enrolled in the study, 109 (27.3%) of them had impaired memory. The analysis of data revealed that the age and marital status had statistical significant association with memory state. Nearly three quarter (72.8%) of study group had depression according to geriatric depression scale. The majority of studied women had depression (90%), and the same percentage was observed among widowed elders joining in the study.
文摘Cognitive decline in Parkinson’s disease (PD) is defined as dementia which affects activities of daily living (ADL) function. Dementia is one of the recognized issues in the treatment of Parkinson’s disease patients (PDP) as it is becoming a major contributor to morbidity. The objective of our study was to evaluate the cognitive decline in Parkinson’s disease patients (PDP) and the influence of cognition on daily living function deterioration in cognitively impaired and cognitively unimpaired PDP. Cognitively impaired PDP (n = 24), and cognitively unimpaired PDP (n = 16) were administered MoCA and MMSE performance based tests for cognitive measurements and Alzheimer’s Disease Cooperative Study Activities of Daily Living Inventory (ADCS-ADL) to determine everyday functioning. The significances of MoCA and MMSE among cognitively impaired PDP and cognitively unimpaired PDP in univariant analysis were P < 0.001 and P < 0.05. In partial correlation, MoCA was strongly related to ADL function as compare to MMSE (r = 0.623, P = 0.001). Cognitively impaired PDP showed significantly lower score on visuo-construction and attention. Among all variables of MoCA domains, attention is strongly associated with instrumental activity daily living (IADL) scores (logistic regression coefficient = 0.672, P = 0.01). These results suggest that dementia affects daily living performances especially the IADL tasks like attention and execution. Therefore, the assessment of complex daily activities particularly IADL is probably useful for the diagnosis of early stage cognitive impairment in PDP. Further MMSE test is less sensitive than MoCA for detecting significant cognitive decline in PDP and impaired attention is an important determinant of ADL functions in cognitively impaired PDP.
基金supported in partially by the National Society Science Fund of China(Grant No.09CJY020)the Special Fund of State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,China(Grant No. 2011585312)+1 种基金the Fundamental Research Funds for the Central Universities of Hohai University2010 Jiangsu Province Qing Lan Project
文摘Due to the increasingly serious environmental pollution and destruction,especially humans' unreasonable activities,the ecological and economic system(EES) issues of Northwest region in China have attracted more and more attention of the researchers.Aiming at evaluating its ecological and economic system health,a multi-objective evaluation framework called PressureState-Response(PSR) was established to describe the ecological and economic health situations.Meanwhile,an integrative set pair model combining set pair analysis(SPA) and fuzzy analytic hierarchy process(FAHP) was proposed to assess the ecological and economic system.Then the EES status of five northwest provinces(Shanxi,Gansu,Qinghai,Ningxia and Xinjiang) of Northwest region in China was evaluated during 1985 to 2009.The EES development trends of five provinces are obtained.In general,the health values of five provinces showed a rising trend.The health values of five provinces grew rapidly during 1985 to 2000.After 2000,the health values of five provinces still followed the present growth trend,but the growth is relatively smooth.The results show that the method proposed is effective for assessing the health of ecological and economic system.
基金This paper is supported by the National High Technology Research and Development Program ("863" Program) of China under Grant No.2006AA04Z437
文摘This paper presents a new method of damage condition assessment that allows accommodating other types of uncertainties due to ambiguity, vagueness, and fuzziness that are statistically nondescribable. In this method, healthy observations are used to construct a fury set representing sound performance characteristics. Additionally, the bounds on the similarities among the structural damage states are prescribed by using the state similarity matrix. Thus, an optimal group fuzzy sets representing damage states such as little, moderate, and severe damage can be inferred as an inverse problem from healthy observations only. The optimal group of damage fuzzy sets is used to classify a set of observations at any unknown state of damage using the principles of fitzzy pattern recognition based on an approximate principle . This method can be embedded into the system of Structural Health Monitoring (SHM) to give advice about structural maintenance and life predictio comes from Reference [ 9 ] for damage pattern recognition is presented n. Finally, a case and discussed. The study, which compared result illustrates our method is more effective and general, so it is very practical in engineering.
基金Supported by Project of Wuxi Municipal Development and Reform Commission (2115019)
文摘Using the method of trophic state-composite index (TSI-CI ) and the 12 months of monitoring data in 2010,we carry out initial exploration of the status of ecosystem health in Wuli Lake. First,we select four indicators,Chla,SD,TP and TN,to conduct trophic state assessment using weighted index method; then after selecting physical,chemical and biological indicators to conduct nondimensionalization processing,we calculate the composite index and conduct comprehensive assessment. The results show that in 2010,the status of ecosystem health in Wuli Lake was the best in July,worst in August; when the composite trophic state indicators with Chla as the representative increase or decrease significantly and cross different nutritional grades,TSI will significantly deviate from CI,and the relationship between the two in the other time is not prominent.
文摘保护状况评估(State of Conservation,SOC)是世界遗产的评估管理环节,目的是持续掌握遗产所面临的各类威胁。文章解读世界遗产SOC评估机制及其发展、完善过程,分析其影响因素指标体系,并结合世界遗产的典型案例,阐释SOC评估在世界遗产保护管理实践中的应用和实效。建议在我国城乡文化遗产保护管理中,建立影响因素评估标准化指标体系以及有效的跟踪和退出机制,以维护文化遗产的价值和遗产名录的可信度,使有限的保护资源得以集中利用。