A statistic-based benchmark was proposed for performance assessment and monitoring of model predic- tive control; the benchmark was straightforward and achievable by recording a set of output data only when the contro...A statistic-based benchmark was proposed for performance assessment and monitoring of model predic- tive control; the benchmark was straightforward and achievable by recording a set of output data only when the control performance was good according to the user’s selection. Principal component model was built and an auto- regressive moving average filter was identified to monitor the performance; an improved T2 statistic was selected as the performance monitor index. When performance changes were detected, diagnosis was done by model validation using recursive analysis and generalized likelihood ratio (GLR) method. This distinguished the fact that the per- formance change was due to plant model mismatch or due to disturbance term. Simulation was done about a heavy oil fractionator system and good results were obtained. The diagnosis result was helpful for the operator to improve the system performance.展开更多
Background： Many studies examining individual-level correlates in youth utilize self-report rather than objective measures of physical activity （PA）. This utilization of self-report may result in associations that ...Background： Many studies examining individual-level correlates in youth utilize self-report rather than objective measures of physical activity （PA）. This utilization of self-report may result in associations that are not present when examining objectively measured PA. The present study investigates the relationship between hypothesized correlates of PA with objectively and subjectively measured PA. Methods： Participating children （n 232, 101 males, mean age - 12.3 years） provided a minimum of four monitored days of PA （via accelerometer） and completed a survey assessing moderate-to-vigorous physical activity （MVPA）, sport competence, appearance, enjoyment, and self-efficacy. Height and weight were measured and body mass index （BMI） was calculated. Results： Hierarchical regression models controlling for sex, race, and BMI Z-score showed that only sex and BMI Z-score were significant correlates of objective MVPA while only sex was a significant correlate of objective total PA. However, in a separate model examining the relationship with subjective MVPA, enjoyment of PA and self-efficacy for PA were the only significant correlates of self-reported PA. Conclusion： Measuring MVPA via self-report versus accelerometry produces considerably different results in a sample of young adolescents. Future studies should use caution when selecting outcome measures if the intent is to identify modifiable correlates of MVPA in youth.展开更多
Internet of things has been widely applied to industrial control, smart city and environmental protection, in these applica- tion scenarios, sensing node needs to make real-time response to the feedback control of the...Internet of things has been widely applied to industrial control, smart city and environmental protection, in these applica- tion scenarios, sensing node needs to make real-time response to the feedback control of the application layer. Therefore, it is nec- essary to monitor whether or not awareness nodes are trusted in real time, but the existing mechanisms for trusted certification lack the real-time measurement and tracking of the sensing node. To solve the above problems, this paper proposes a dynamic metric based authentication mechanism for sensing nodes of Internet of things. Firstly, the dynamic trustworthiness measure of the sensing nodes is carried out by introducing the computational function such as the trust function, the trust- worthiness risk assessment function, the feed- back control function and the active function of the sensing node. The dynamic trustworthi- ness measure of sensing nodes from multiple dimensions can effectively describe the change of trusted value of sensing nodes. Then, on the basis of this, a trusted attestation based on node trusted measure is realized by using the revocable group signature mechanism of local verifier. The mechanism has anonymity, un- forgeability and traceability, which is proved the security in the standard model. Simulationexperiments show that the proposed trusted attestation mechanism is flexible, practical and ef｜Scient and has better attack resistance. It can effectively guarantee the reliable data transmission of nodes and realize the dynamic tracking of node reliability, which has a lower impact on system performance.展开更多
Surveying control network optimization design is related to standards, such as precision, reliability, sensitivity and the cost, and these standards are related closely to each other. A new method for surveying contro...Surveying control network optimization design is related to standards, such as precision, reliability, sensitivity and the cost, and these standards are related closely to each other. A new method for surveying control network simulation optimization design is proposed. This method is based on the inner reliability index of the observation values.展开更多
To minimize losses between harvest and retail display, a system is needed to track temperature and RH exposure of fresh produce and predict its quality at each step of the distribution chain. With accurate models, suc...To minimize losses between harvest and retail display, a system is needed to track temperature and RH exposure of fresh produce and predict its quality at each step of the distribution chain. With accurate models, such system could （1） identify problematic situations before losses occur; （2） become a management tool for decision makers; and （3） help quantify the real impact of individual inappropriate conditions. A project was initiated to develop models required for such a decision system. Because the data required to develop models were not available for most fruit and vegetables, a series of storage trials was planned for measuring changes in physiological and microbial quality, and development of physiological disorders and/or diseases, as a function of time, temperature and RH. To meet this objective, controlled environment mini-chambers were designed, built and instrumented for measuring the effect of traceable environmental conditions encountered during storage and transportation of fresh horticultural produce of similar size and shape as tomato. Detailed design and performance evaluation of these mini-chambers are presented.展开更多
In order to construct the trusted network and realize the trust of network behavior,a new multi-dimensional behavior measurement model based on prediction and control is presented.By using behavior predictive equation...In order to construct the trusted network and realize the trust of network behavior,a new multi-dimensional behavior measurement model based on prediction and control is presented.By using behavior predictive equation,individual similarity function,group similarity function,direct trust assessment function,and generalized predictive control,this model can guarantee the trust of an end user and users in its network.Compared with traditional measurement model,the model considers different characteristics of various networks.The trusted measurement policies established according to different network environments have better adaptability.By constructing trusted group,the threats to trusted group will be reduced greatly.Utilizing trusted group to restrict individuals in network can ensure the fault tolerance of trustworthiness of trusted individuals and group.The simulation shows that this scheme can support behavior measurement more efficiently than traditional ones and the model resists viruses and Trojans more efficiently than older ones.展开更多
A cantilever coordinate measuring machine(CCMM)is proposed according to the in-situ measurement requirement of workpieces with complex structures limited by the finite space of the5-axes computerized numerical control...A cantilever coordinate measuring machine(CCMM)is proposed according to the in-situ measurement requirement of workpieces with complex structures limited by the finite space of the5-axes computerized numerical control(CNC)processing site.Factors affecting uncertainty of measurement(UM)are classified and analyzed on the basis of uncertainty evaluation criteria,and the estimation technique of UM for measuring systems is presented.UM of the CCMM is estimated from the factors such as temperature,error motions as well as the mechanism deformations.Measurement results show that the actual measurement error is smaller than that of measurement requirement.展开更多
This is a greenhouse ecological parameters measurement and control system, the system implements the data collection of field temperature, humidity and carbon dioxide by using the 1-wire bus network which consist of 1...This is a greenhouse ecological parameters measurement and control system, the system implements the data collection of field temperature, humidity and carbon dioxide by using the 1-wire bus network which consist of 1-wire bus temperature sensor, 1-wire bus humidity sensor, Analog-to-Digital Converter（ADC）, CO2 sensor and intelligent battery monitor.展开更多
The study presents possibilities for reconstruction of electric power supply systems in Bulgarian Black Sea resorts and possibilities to use statistical methods in energy planning. The paper shows the use of classic s...The study presents possibilities for reconstruction of electric power supply systems in Bulgarian Black Sea resorts and possibilities to use statistical methods in energy planning. The paper shows the use of classic statistical methods in combination with advanced digital measurement systems in order to obtain the correlation dependencies, nature of energy consumption and opportunities for energy forecasting. The main purpose of the study is to obtain statistical dependencies of the nature of power consumption and correlations between electricity consumption and ambient temperature in order to improve the accuracy of energy planning. The analysis includes application of energy management systems for proper energy planning, improving economical efficiency and reducing power and energy losses.展开更多
基金Supported by the National Natural Science Foundation of China (Nos.60474051, 60534020), the Key Technology and Devel-opment Program of Shanghai Science and Technology Department (No.04DZ11008), and the Program for New Century Ex-cellent Talents in the University of China (NCET).
文摘A statistic-based benchmark was proposed for performance assessment and monitoring of model predic- tive control; the benchmark was straightforward and achievable by recording a set of output data only when the control performance was good according to the user’s selection. Principal component model was built and an auto- regressive moving average filter was identified to monitor the performance; an improved T2 statistic was selected as the performance monitor index. When performance changes were detected, diagnosis was done by model validation using recursive analysis and generalized likelihood ratio (GLR) method. This distinguished the fact that the per- formance change was due to plant model mismatch or due to disturbance term. Simulation was done about a heavy oil fractionator system and good results were obtained. The diagnosis result was helpful for the operator to improve the system performance.
基金funded by the Centers for Disease Control and Prevention(K01-DP001126)
文摘Background： Many studies examining individual-level correlates in youth utilize self-report rather than objective measures of physical activity （PA）. This utilization of self-report may result in associations that are not present when examining objectively measured PA. The present study investigates the relationship between hypothesized correlates of PA with objectively and subjectively measured PA. Methods： Participating children （n 232, 101 males, mean age - 12.3 years） provided a minimum of four monitored days of PA （via accelerometer） and completed a survey assessing moderate-to-vigorous physical activity （MVPA）, sport competence, appearance, enjoyment, and self-efficacy. Height and weight were measured and body mass index （BMI） was calculated. Results： Hierarchical regression models controlling for sex, race, and BMI Z-score showed that only sex and BMI Z-score were significant correlates of objective MVPA while only sex was a significant correlate of objective total PA. However, in a separate model examining the relationship with subjective MVPA, enjoyment of PA and self-efficacy for PA were the only significant correlates of self-reported PA. Conclusion： Measuring MVPA via self-report versus accelerometry produces considerably different results in a sample of young adolescents. Future studies should use caution when selecting outcome measures if the intent is to identify modifiable correlates of MVPA in youth.
基金supported by the National Natural Science Foundation of China (The key trusted running technologies for the sensing nodes in Internet of things: 61501007, The research of the trusted and security environment for high energy physics scientific computing system: 11675199)General Project of science and technology project of Beijing Municipal Education Commission: KM201610005023+2 种基金the outstanding personnel training program of Beijing municipal Party Committee Organization Department (The Research of Trusted Computing environment for Internet of things in Smart City: 2014000020124G041)The key technology research and validation issue for the emergency treatment telemedicine public service platform which integrates the military and civilian and bases on the broadband wireless networks (No.2013ZX03006001-005)the issue belongs to Major national science and technology projects
文摘Internet of things has been widely applied to industrial control, smart city and environmental protection, in these applica- tion scenarios, sensing node needs to make real-time response to the feedback control of the application layer. Therefore, it is nec- essary to monitor whether or not awareness nodes are trusted in real time, but the existing mechanisms for trusted certification lack the real-time measurement and tracking of the sensing node. To solve the above problems, this paper proposes a dynamic metric based authentication mechanism for sensing nodes of Internet of things. Firstly, the dynamic trustworthiness measure of the sensing nodes is carried out by introducing the computational function such as the trust function, the trust- worthiness risk assessment function, the feed- back control function and the active function of the sensing node. The dynamic trustworthi- ness measure of sensing nodes from multiple dimensions can effectively describe the change of trusted value of sensing nodes. Then, on the basis of this, a trusted attestation based on node trusted measure is realized by using the revocable group signature mechanism of local verifier. The mechanism has anonymity, un- forgeability and traceability, which is proved the security in the standard model. Simulationexperiments show that the proposed trusted attestation mechanism is flexible, practical and ef｜Scient and has better attack resistance. It can effectively guarantee the reliable data transmission of nodes and realize the dynamic tracking of node reliability, which has a lower impact on system performance.
文摘Surveying control network optimization design is related to standards, such as precision, reliability, sensitivity and the cost, and these standards are related closely to each other. A new method for surveying control network simulation optimization design is proposed. This method is based on the inner reliability index of the observation values.
文摘To minimize losses between harvest and retail display, a system is needed to track temperature and RH exposure of fresh produce and predict its quality at each step of the distribution chain. With accurate models, such system could （1） identify problematic situations before losses occur; （2） become a management tool for decision makers; and （3） help quantify the real impact of individual inappropriate conditions. A project was initiated to develop models required for such a decision system. Because the data required to develop models were not available for most fruit and vegetables, a series of storage trials was planned for measuring changes in physiological and microbial quality, and development of physiological disorders and/or diseases, as a function of time, temperature and RH. To meet this objective, controlled environment mini-chambers were designed, built and instrumented for measuring the effect of traceable environmental conditions encountered during storage and transportation of fresh horticultural produce of similar size and shape as tomato. Detailed design and performance evaluation of these mini-chambers are presented.
基金This work was supported by the National Basic Research Pro-gram of China under Crant No.2007CB311100 Funds of Key Lab of Fujlan Province University Network Security and Cryp- toll1009+3 种基金 the National Science Foundation for Young Scholars of China under Crant No.61001091 Beijing Nature Science Foundation under Crant No. 4122012 ＂Next-Generation Broad-band Wireless Mobile Communication Network＂ National Sci-ence and Technology Major Special Issue Funding under Grant No. 2012ZX03002003 Funding Program for Academic tturmn Resources Development in Institutions of Higher Learning Under the Jurisdiction of Beijing Municipality of Chi-na.
文摘In order to construct the trusted network and realize the trust of network behavior,a new multi-dimensional behavior measurement model based on prediction and control is presented.By using behavior predictive equation,individual similarity function,group similarity function,direct trust assessment function,and generalized predictive control,this model can guarantee the trust of an end user and users in its network.Compared with traditional measurement model,the model considers different characteristics of various networks.The trusted measurement policies established according to different network environments have better adaptability.By constructing trusted group,the threats to trusted group will be reduced greatly.Utilizing trusted group to restrict individuals in network can ensure the fault tolerance of trustworthiness of trusted individuals and group.The simulation shows that this scheme can support behavior measurement more efficiently than traditional ones and the model resists viruses and Trojans more efficiently than older ones.
基金National Natural Science Foundation of China(No.51375338)
文摘A cantilever coordinate measuring machine(CCMM)is proposed according to the in-situ measurement requirement of workpieces with complex structures limited by the finite space of the5-axes computerized numerical control(CNC)processing site.Factors affecting uncertainty of measurement(UM)are classified and analyzed on the basis of uncertainty evaluation criteria,and the estimation technique of UM for measuring systems is presented.UM of the CCMM is estimated from the factors such as temperature,error motions as well as the mechanism deformations.Measurement results show that the actual measurement error is smaller than that of measurement requirement.
文摘This is a greenhouse ecological parameters measurement and control system, the system implements the data collection of field temperature, humidity and carbon dioxide by using the 1-wire bus network which consist of 1-wire bus temperature sensor, 1-wire bus humidity sensor, Analog-to-Digital Converter（ADC）, CO2 sensor and intelligent battery monitor.
文摘The study presents possibilities for reconstruction of electric power supply systems in Bulgarian Black Sea resorts and possibilities to use statistical methods in energy planning. The paper shows the use of classic statistical methods in combination with advanced digital measurement systems in order to obtain the correlation dependencies, nature of energy consumption and opportunities for energy forecasting. The main purpose of the study is to obtain statistical dependencies of the nature of power consumption and correlations between electricity consumption and ambient temperature in order to improve the accuracy of energy planning. The analysis includes application of energy management systems for proper energy planning, improving economical efficiency and reducing power and energy losses.
