This paper discusses some issues on human reliability model of time dependent human behavior. Some results of the crew reliability experiment on Tsinghua training simulator in China are given, Meanwhile, a case of ca...This paper discusses some issues on human reliability model of time dependent human behavior. Some results of the crew reliability experiment on Tsinghua training simulator in China are given, Meanwhile, a case of calculation for human error probability during anticipated transient without scram (ATWS) based on the data drew from the recent experiment is offered.展开更多
The majority of existing papers about spectrum sensing have the assumption that secondary users(SUs) are stationary. However,mobility is an essential feature of mobile communications networks. In this paper,the detect...The majority of existing papers about spectrum sensing have the assumption that secondary users(SUs) are stationary. However,mobility is an essential feature of mobile communications networks. In this paper,the detection performance of spectrum sensing by mobile SUs was analyzed. Three performance metrics,i.e.,detection probability,miss detection probability and false alarm probability,were thoroughly investigated. In our analysis,a critical variable was the real-time received primary user signal power by a mobile SU. Its probability distribution and mathematical expectation were analytically derived. Moreover,the three performance metrics in single-node spectrum sensing and multi-node collaborative spectrum sensing systems were also derived. Extensive simulations were performed. The results are consistent with the theoretical analysis. And it is concluded that SU mobility has a significant impact on the detection probability and the miss detection probability,but not on the false alarm probability.展开更多
In order to understand the influence of brittleness and confining stress on rock cuttability,the indentation tests were carried out by a conical pick on the four types of rocks.Then,the experimental results were utili...In order to understand the influence of brittleness and confining stress on rock cuttability,the indentation tests were carried out by a conical pick on the four types of rocks.Then,the experimental results were utilized to take regression analysis.The eight sets of normalized regression models were established for reflecting the relationships of peak indentation force(PIF)and specific energy(SE)with brittleness index and uniaxial confining stress.The regression analyses present that these regression models have good prediction performance.The regressive results indicate that brittleness indices and uniaxial confining stress conditions have non-linear effects on the rock cuttability that is determined by PIF and SE.Finally,the multilayer perceptual neural network was used to measure the importance weights of brittleness index and uniaxial confining stress upon the influence for rock cuttability.The results indicate that the uniaxial confining stress is more significant than brittleness index for influencing the rock cuttability.展开更多
AIM: To perform a systematic meta-analysis to in- vestigate the association between X-ray repair crosscomplementing group 1 (XRCC1) polymorphisms and hepatocellular carcinoma (HCC) risk. METHODS: Relevant studie...AIM: To perform a systematic meta-analysis to in- vestigate the association between X-ray repair crosscomplementing group 1 (XRCC1) polymorphisms and hepatocellular carcinoma (HCC) risk. METHODS: Relevant studies extracted from PubMed, Embase, Wanfang, VIP and the Chinese National Knowledge Infrastructure databases up to March 2012 were included in the study. Stata software, version 11.0, was used for the statistical analysis. The odds ratios (ORs) and 95% confidence interval (CI) of the XRCC1 polymorphisms in HCC patients were analyzed and compared with healthy controls. The meta-analysis was performed using fixed-effect or random-effect methods, depending on the absence or presence of significant heterogeneity. RESULTS: Eleven studies with 2075 HCC cases and 2604 controls met our eligibility criteria (four studies, 888 cases and 938 controls for Arg194Trp, four studies, 858 cases and 880 controls for Arg280His, and nine studies, 1845 cases and 2401 controls for Arg399Gln). The meta-analysis revealed no associations between the Arg194Trp and Arg399GIn polymorphisms of the XRCC1 gene and HCC risk under all contrast models (codominant, dominant and recessive models) in the overall analysis and sensitivity analysis (the studies with controls not in the Hardy-Weinberg equilibrium were excluded). For XRCC1 Arg280His polymorphism, the overall analysis revealed the significant associa- tion between the His/His genotype and the increased risk of HCC (His/His vs Arg/Arg model, OR: 1.96, 95% CI: 1.03-3.75, P = 0.04). However, sensitivity analysis showed an altered pattern of result and non-significant association (OR: 2.06, 95% CI: 0.67-6.25, P = 0.20). The heterogeneity hypothesis test did not reveal any heterogeneity, and Begg's and Egger's tests did not find any obvious publication bias. CONCLUSION: The XRCC1 Arg194Trp and Arg399GIn polymorphisms are not associated with HCC risk. More rigorous association studies are needed to verify the involvement ofXRCC1 Arg280His polymorphism in HCC susceptibility.展开更多
In this paper, we first overview some traditional relaying technologies, and then present a Network Coding-Aware Cooperative Relaying (NC2R) scheme to improve the performance of downlink transmission for relayaided ...In this paper, we first overview some traditional relaying technologies, and then present a Network Coding-Aware Cooperative Relaying (NC2R) scheme to improve the performance of downlink transmission for relayaided cellular networks. Moreover, systematic performance analysis and extensive simulations are performed for the proposed NC2R and traditional relaying and non-relaying schemes. The results show that NCR outperforms conventional relaying and non-relaying schemes in terms of blocking probability and spectral efficiency, especially for cell-edge users. Additionally, the location selections for relays with NCR are also discussed. These results will provide some insights for incorporating network coding into next-generation broadband cellular relay mobile systems.展开更多
The cloud computing has been growing over the past few years, and service providers are creating an intense competitive world of business. This proliferation makes it hard for new users to select a proper service amon...The cloud computing has been growing over the past few years, and service providers are creating an intense competitive world of business. This proliferation makes it hard for new users to select a proper service among a large amount of service candidates. A novel user preferences-aware recommendation approach for trustworthy services is presented. For describing the requirements of new users in different application scenarios, user preferences are identified by usage preference, trust preference and cost preference. According to the similarity analysis of usage preference between consumers and new users, the candidates are selected, and these data about service trust provided by them are calculated as the fuzzy comprehensive evaluations. In accordance with the trust and cost preferences of new users, the dynamic fuzzy clusters are generated based on the fuzzy similarity computation. Then, the most suitable services can be selected to recommend to new users. The experiments show that this approach is effective and feasible, and can improve the quality of services recommendation meeting the requirements of new users in different scenario.展开更多
In this paper, the energy-efficient power control problem in cognitive radio (CR) networks is studied not only to provide energy-efficient transmission, but also to guarantee the normal operation of primary users (...In this paper, the energy-efficient power control problem in cognitive radio (CR) networks is studied not only to provide energy-efficient transmission, but also to guarantee the normal operation of primary users (PUs). Moreover, the static energy-efficient power control (SEPC) algorithm is proposed in static scenario to maximize the capacity of secondary users (SUs) and to reduce the power consumption according to the interference from PU to SU. Furthermore, based on the analysis of PU's dynamic feature with Markov chain and SEPC algorithm,the dynamic energy-efficient power control (DEPC) algorithm is proposed taking into account the probability of detection and false alarm caused by sensing errors. Extensive simulation results show that the performance of the proposed algorithms is significantly improved compared with the existing algorithm.展开更多
The relative difficulty of capturing and conveying knowledge is determined on the diversity of knowledge types. It is necessary to interpret the consciously capturing process of the knowledge that is formed unconsciou...The relative difficulty of capturing and conveying knowledge is determined on the diversity of knowledge types. It is necessary to interpret the consciously capturing process of the knowledge that is formed unconsciously. Storytelling is important in the capturing and conveying of tacit knowledge. Culture, structure, system, and the knowledge holders within the organization also affect the transfer of personal knowledge. The company M, has successfully created knowledge based on transfer of personal knowledge by leveraging the organization mechanism "The board of advisors". In order to elucidate the process, the author analyzed the recordings of the passing on contents using the protocol analysis.展开更多
文摘This paper discusses some issues on human reliability model of time dependent human behavior. Some results of the crew reliability experiment on Tsinghua training simulator in China are given, Meanwhile, a case of calculation for human error probability during anticipated transient without scram (ATWS) based on the data drew from the recent experiment is offered.
基金supported by National Natural Science Foundation of China under Grand No.61671183
文摘The majority of existing papers about spectrum sensing have the assumption that secondary users(SUs) are stationary. However,mobility is an essential feature of mobile communications networks. In this paper,the detection performance of spectrum sensing by mobile SUs was analyzed. Three performance metrics,i.e.,detection probability,miss detection probability and false alarm probability,were thoroughly investigated. In our analysis,a critical variable was the real-time received primary user signal power by a mobile SU. Its probability distribution and mathematical expectation were analytically derived. Moreover,the three performance metrics in single-node spectrum sensing and multi-node collaborative spectrum sensing systems were also derived. Extensive simulations were performed. The results are consistent with the theoretical analysis. And it is concluded that SU mobility has a significant impact on the detection probability and the miss detection probability,but not on the false alarm probability.
基金Project(51904333) supported by the National Natural Science Foundation of China。
文摘In order to understand the influence of brittleness and confining stress on rock cuttability,the indentation tests were carried out by a conical pick on the four types of rocks.Then,the experimental results were utilized to take regression analysis.The eight sets of normalized regression models were established for reflecting the relationships of peak indentation force(PIF)and specific energy(SE)with brittleness index and uniaxial confining stress.The regression analyses present that these regression models have good prediction performance.The regressive results indicate that brittleness indices and uniaxial confining stress conditions have non-linear effects on the rock cuttability that is determined by PIF and SE.Finally,the multilayer perceptual neural network was used to measure the importance weights of brittleness index and uniaxial confining stress upon the influence for rock cuttability.The results indicate that the uniaxial confining stress is more significant than brittleness index for influencing the rock cuttability.
基金Supported by International Science and Technology Cooperation Program of the Ministry of Science and Technology,No.010S2012ZR0058the National Basic Research Program of China,No. 2012CB526706+2 种基金the Innovation Program of Shanghai Municipal Education Commission,No.13ZZ060the Fund of Shanghai Municipal Health Bureau,No. 2008Y077the Special Program for Military Medicine,No. 2010JS15
文摘AIM: To perform a systematic meta-analysis to in- vestigate the association between X-ray repair crosscomplementing group 1 (XRCC1) polymorphisms and hepatocellular carcinoma (HCC) risk. METHODS: Relevant studies extracted from PubMed, Embase, Wanfang, VIP and the Chinese National Knowledge Infrastructure databases up to March 2012 were included in the study. Stata software, version 11.0, was used for the statistical analysis. The odds ratios (ORs) and 95% confidence interval (CI) of the XRCC1 polymorphisms in HCC patients were analyzed and compared with healthy controls. The meta-analysis was performed using fixed-effect or random-effect methods, depending on the absence or presence of significant heterogeneity. RESULTS: Eleven studies with 2075 HCC cases and 2604 controls met our eligibility criteria (four studies, 888 cases and 938 controls for Arg194Trp, four studies, 858 cases and 880 controls for Arg280His, and nine studies, 1845 cases and 2401 controls for Arg399Gln). The meta-analysis revealed no associations between the Arg194Trp and Arg399GIn polymorphisms of the XRCC1 gene and HCC risk under all contrast models (codominant, dominant and recessive models) in the overall analysis and sensitivity analysis (the studies with controls not in the Hardy-Weinberg equilibrium were excluded). For XRCC1 Arg280His polymorphism, the overall analysis revealed the significant associa- tion between the His/His genotype and the increased risk of HCC (His/His vs Arg/Arg model, OR: 1.96, 95% CI: 1.03-3.75, P = 0.04). However, sensitivity analysis showed an altered pattern of result and non-significant association (OR: 2.06, 95% CI: 0.67-6.25, P = 0.20). The heterogeneity hypothesis test did not reveal any heterogeneity, and Begg's and Egger's tests did not find any obvious publication bias. CONCLUSION: The XRCC1 Arg194Trp and Arg399GIn polymorphisms are not associated with HCC risk. More rigorous association studies are needed to verify the involvement ofXRCC1 Arg280His polymorphism in HCC susceptibility.
基金supported by the State Key Laboratory of Rail Traffic Control and Safety,Beijing Jiaotong University under Grant No.RCS2012ZT008the National Key Basic Research Program of China(973Program)under Grant No.2012CB316100(2)+1 种基金the National Natural Science Foundation of China under Grants No.61201203,No.61171064the Fundamental Research Funds for the Central Universities under Grant No.2012JBM030
文摘In this paper, we first overview some traditional relaying technologies, and then present a Network Coding-Aware Cooperative Relaying (NC2R) scheme to improve the performance of downlink transmission for relayaided cellular networks. Moreover, systematic performance analysis and extensive simulations are performed for the proposed NC2R and traditional relaying and non-relaying schemes. The results show that NCR outperforms conventional relaying and non-relaying schemes in terms of blocking probability and spectral efficiency, especially for cell-edge users. Additionally, the location selections for relays with NCR are also discussed. These results will provide some insights for incorporating network coding into next-generation broadband cellular relay mobile systems.
基金Project(61272148) supported by the National Natural Science Foundation of ChinaProject(2014FJ3122) supported by the Science and Technology Project of Hunan Province,China
文摘The cloud computing has been growing over the past few years, and service providers are creating an intense competitive world of business. This proliferation makes it hard for new users to select a proper service among a large amount of service candidates. A novel user preferences-aware recommendation approach for trustworthy services is presented. For describing the requirements of new users in different application scenarios, user preferences are identified by usage preference, trust preference and cost preference. According to the similarity analysis of usage preference between consumers and new users, the candidates are selected, and these data about service trust provided by them are calculated as the fuzzy comprehensive evaluations. In accordance with the trust and cost preferences of new users, the dynamic fuzzy clusters are generated based on the fuzzy similarity computation. Then, the most suitable services can be selected to recommend to new users. The experiments show that this approach is effective and feasible, and can improve the quality of services recommendation meeting the requirements of new users in different scenario.
基金the National Natural Science Foundation of China,Beijing Municipal Natural Science Foundation,the Key Project of Ministry of Industry and Information Technology,the National Youth Science Foundation
文摘In this paper, the energy-efficient power control problem in cognitive radio (CR) networks is studied not only to provide energy-efficient transmission, but also to guarantee the normal operation of primary users (PUs). Moreover, the static energy-efficient power control (SEPC) algorithm is proposed in static scenario to maximize the capacity of secondary users (SUs) and to reduce the power consumption according to the interference from PU to SU. Furthermore, based on the analysis of PU's dynamic feature with Markov chain and SEPC algorithm,the dynamic energy-efficient power control (DEPC) algorithm is proposed taking into account the probability of detection and false alarm caused by sensing errors. Extensive simulation results show that the performance of the proposed algorithms is significantly improved compared with the existing algorithm.
文摘The relative difficulty of capturing and conveying knowledge is determined on the diversity of knowledge types. It is necessary to interpret the consciously capturing process of the knowledge that is formed unconsciously. Storytelling is important in the capturing and conveying of tacit knowledge. Culture, structure, system, and the knowledge holders within the organization also affect the transfer of personal knowledge. The company M, has successfully created knowledge based on transfer of personal knowledge by leveraging the organization mechanism "The board of advisors". In order to elucidate the process, the author analyzed the recordings of the passing on contents using the protocol analysis.