This study presented a simulation-based two-stage interval-stochastic programming （STIP） model to support water resources management in the Kaidu-Konqi watershed in Northwest China. The modeling system coupled a dis...This study presented a simulation-based two-stage interval-stochastic programming （STIP） model to support water resources management in the Kaidu-Konqi watershed in Northwest China. The modeling system coupled a distributed hydrological model with an interval two-stage stochastic programing （ITSP）. The distributed hydrological model was used for establishing a rainfall-runoff forecast system, while random parameters were pro- vided by the statistical analysis of simulation outcomes water resources management planning in Kaidu-Konqi The developed STIP model was applied to a real case of watershed, where three scenarios with different water re- sources management policies were analyzed. The results indicated that water shortage mainly occurred in agri- culture, ecology and forestry sectors. In comparison, the water demand from municipality, industry and stock- breeding sectors can be satisfied due to their lower consumptions and higher economic values. Different policies for ecological water allocation can result in varied system benefits, and can help to identify desired water allocation plans with a maximum economic benefit and a minimum risk of system disruption under uncertainty.展开更多
This paper introduces a practical solving scheme of gradetransition trajectory optimization(GTTO) problems under typical certificate-checking–updating framework. Due to complicated kinetics of polymerization,differen...This paper introduces a practical solving scheme of gradetransition trajectory optimization(GTTO) problems under typical certificate-checking–updating framework. Due to complicated kinetics of polymerization,differential/algebraic equations(DAEs) always cause great computational burden and system non-linearity usually makes GTTO non-convex bearing multiple optima. Therefore, coupled with the three-stage decomposition model, a three-section algorithm of dynamic programming(TSDP) is proposed based on the general iteration mechanism of iterative programming(IDP) and incorporated with adaptivegrid allocation scheme and heuristic modifications. The algorithm iteratively performs dynamic programming with heuristic modifications under constant calculation loads and adaptively allocates the valued computational resources to the regions that can further improve the optimality under the guidance of local error estimates. TSDP is finally compared with IDP and interior point method(IP) to verify its efficiency of computation.展开更多
Aim: We devised a self-care supporting program targeting patients with early stages of secondary lower-limb lymphedema. The program incorporates “Simple exercises to replace lymphatic drainage” based on lymphatic fl...Aim: We devised a self-care supporting program targeting patients with early stages of secondary lower-limb lymphedema. The program incorporates “Simple exercises to replace lymphatic drainage” based on lymphatic flow. The purpose of this study was to consider the feasibility of continuing this program. Methods: The participants were patients in the early stages of secondary lower-limb lymphedema after gynecological cancer surgery and lymphedema therapists with more than five years of experience. Patients continued self-care at home after being briefed on the program, and they were analyzed on their self-care continuity status one month later based on a self-administered questionnaire survey and self-care notes. We interviewed the lymphedema therapists about this program to discuss the feasibility of continuing it and obtain feedback. Results: The patients who participated in the study were six women who underwent surgery with lymph node dissection for gynecological cancer. The therapists were five nurses and one occupational therapist. The patient understood the importance of all items in the self-care. “Observation,” “Touching,” and “Skin care” were relatively easy to continue. “Lymph drainage” and “Exercise” were continued with “Simple exercises to replace lymphatic drainage”. “Other exercises” were able to continue by adding distance and time to daily activities. Furthermore, “Measurement” and “Recording” became a burden and were difficult to continue. Nonetheless, this program was generally approved by the lymphedema therapists. They also pointed out the content and format of the self-care notes as improvements. Conclusions: We found that the self-care supporting program that incorporated “Simple exercises to replace lymphatic drainage” might be feasible to continue self-care for patients with early stages of secondary lower-limb lymphedema. Furthermore, we found that we needed to improve the “Measurement” and “Recording” sections of this program.展开更多
An optimization design technique to obtain global solution for a two-stage operational amplifier(op-amp) with frequency compensation is presented.This frequency compensation technique can adjust the equivalent resista...An optimization design technique to obtain global solution for a two-stage operational amplifier(op-amp) with frequency compensation is presented.This frequency compensation technique can adjust the equivalent resistance to guarantee that the phase margin is stable even though circumstance temperature varies.Geometric programming is used to optimize the component values and transistor dimensions.It is used in this analog integrated circuit design to calculate these parameters automatically.This globally optimal amplifier obtains minimum power while other specifications are fulfilled.展开更多
该文提出一种考虑故障后多阶段恢复的智能软开关(soft open point,SOP)柔性互联配电网(flexible interconnected distribution network,FIDN)可靠性评估方法,其特征在于将基于SOP的FIDN网络拓扑状态通过优化过程的决策变量显式表达,建...该文提出一种考虑故障后多阶段恢复的智能软开关(soft open point,SOP)柔性互联配电网(flexible interconnected distribution network,FIDN)可靠性评估方法,其特征在于将基于SOP的FIDN网络拓扑状态通过优化过程的决策变量显式表达,建立面向FIDN可靠性评估的混合整数线性规划模型,从而实现FIDN可靠性评估。首先,分析FIDN多阶段恢复过程,提出一种多阶段恢复过程解耦建模的FIDN可靠性评估框架;然后,基于SOP正常运行和不同故障下的外特性,建立面向可靠性评估的SOP等效模型,构建FIDN节点-支路状态关联模型以实现网络拓扑状态显式化;之后,考虑SOP转供功率约束及短时过载能力,建立不同策略下的SOP快速转供模型;在此基础上,考虑SOP快速转供、故障点上游恢复、联络开关切换转供、孤岛运行等多阶段恢复过程,建立面向FIDN可靠性评估的混合整数线性规划模型;最后,在改进的37节点系统上验证所提方法的有效性。展开更多
Oil and gas pipeline networks are a key link in the coordinated development of oil and gas both upstream and downstream.To improve the reliability and safety of the oil and gas pipeline network, inspections are implem...Oil and gas pipeline networks are a key link in the coordinated development of oil and gas both upstream and downstream.To improve the reliability and safety of the oil and gas pipeline network, inspections are implemented to minimize the risk of leakage, spill and theft, as well as documenting actual incidents. In recent years, unmanned aerial vehicles have been recognized as a promising option for inspection due to their high efficiency. However, the integrated optimization of unmanned aerial vehicle inspection for oil and gas pipeline networks, including physical feasibility, the performance of mission, cooperation, real-time implementation and three-dimensional(3-D) space, is a strategic problem due to its large-scale,complexity as well as the need for efficiency. In this work, a novel mixed-integer nonlinear programming model is proposed that takes into account the constraints of the mission scenario and the safety performance of unmanned aerial vehicles. To minimize the total length of the inspection path, the model is solved by a two-stage solution method. Finally, a virtual pipeline network and a practical pipeline network are set as two examples to demonstrate the performance of the optimization schemes. Moreover, compared with the traditional genetic algorithm and simulated annealing algorithm, the self-adaptive genetic simulated annealing algorithm proposed in this paper provides strong stability.展开更多
We present an approximation-exact penalty function method for solving the single stage stochastic programming problem with continuous random variable. The original problem is transformed into a determinate nonlinear p...We present an approximation-exact penalty function method for solving the single stage stochastic programming problem with continuous random variable. The original problem is transformed into a determinate nonlinear programming problem with a discrete random variable sequence, which is obtained by some discrete method. We construct an exact penalty function and obtain an unconstrained optimization. It avoids the difficulty in solution by the rapid growing of the number of constraints for discrete precision. Under lenient conditions, we prove the equivalence of the minimum solution of penalty function and the solution of the determinate programming, and prove that the solution sequences of the discrete problem converge to a solution to the original problem.展开更多
In this study, an interval probability-based inexact two-stage stochastic (IP-ITSP) model is developed for environmental pollutants control and greenhouse gas (GHG) emissions reduction management in regional energy sy...In this study, an interval probability-based inexact two-stage stochastic (IP-ITSP) model is developed for environmental pollutants control and greenhouse gas (GHG) emissions reduction management in regional energy system under uncertainties. In the IP-ITSP model, methods of interval probability, interval-parameter programming (IPP) and two-stage stochastic programming (TSP) are introduced into an integer programming framework;the developed model can tackle uncertainties described in terms of interval values and interval probability distributions. The developed model is applied to a case of planning GHG -emission mitigation in a regional electricity system, demonstrating that IP-ITSP is applicable to reflecting complexities of multi-uncertainty, and capable of addressing the problem of GHG-emission reduction. 4 scenarios corresponding to different GHG -emission mitigation levels are examined;the results indicates that the model could help decision makers identify desired GHG mitigation policies under various economic costs and environmental requirements.展开更多
Having lectured in some universities and polytechnics in Nigeria, the researchers observed problems in course allocations. There are no lay-down techniques on how courses should be allocated with respect to the minimu...Having lectured in some universities and polytechnics in Nigeria, the researchers observed problems in course allocations. There are no lay-down techniques on how courses should be allocated with respect to the minimum and maximum credit a lecturer should carry in a semester. Many lecturers were overloaded while others were under-loaded. For this reason, dynamic programming model was developed for allocating courses among lecturers in the Nigerian universities using the Department of Statistics, Federal University of Technology Owerri, as a case study. From our analysis, we observed that among all the optimal allocations discovered in the study, the best optimal allocation policy was achieved at the point (1, 2, 1, 2). Allocation of courses in this order will yield an optimal credit hour of 12 per lecturer per semester.展开更多
AIM:To investigate if and how programmed death type-1(PD-1)expression affects the natural course of hepatitis B virus(HBV)infection. METHODS:Sixty-four patients in different natural stages of chronic HBV infection wer...AIM:To investigate if and how programmed death type-1(PD-1)expression affects the natural course of hepatitis B virus(HBV)infection. METHODS:Sixty-four patients in different natural stages of chronic HBV infection were enrolled in this study.PD-1 expression in total T cells was detected by flow cytometry.Levels of total CD8+T cell responses and proliferation in relation to PD-1 expression levels were analyzed with intracellular staining and PD-1/ PD-L1 blockage. RESULTS:The PD-1 expression in T cells was dynamically changed during the natural course of chronic HBV infection,did not significantly increase in the immune tolerance phase,and returned to normal in the inactive virus carrier stage.Blockage of the PD-1/PD-L1 pathway could not affect the T-cell response in the immune tolerance and inactive virus carrier stages of chronic HBV infection.However,it could significantly restore the T-cell response in the immune clearance stage of chronic HBV infection.Furthermore,the PD-1 expression level in T cells was associated with the alanine aminotransferase level during the immune clearance stage of chronic HBV infection. CONCLUSION:The PD-l/PD-L1 pathway plays a different role in T-cell response during the natural course of chronic HBV infection.展开更多
基金supported by the National Basic Research Program of China(2010CB951002)the Dr.Western-funded Project of Chinese Academy of Science(XBBS201010 and XBBS201005)+1 种基金the National Natural Sciences Foundation of China (51190095)the Open Research Fund Program of State Key Laboratory of Hydro-science and Engineering(sklhse-2012-A03)
文摘This study presented a simulation-based two-stage interval-stochastic programming （STIP） model to support water resources management in the Kaidu-Konqi watershed in Northwest China. The modeling system coupled a distributed hydrological model with an interval two-stage stochastic programing （ITSP）. The distributed hydrological model was used for establishing a rainfall-runoff forecast system, while random parameters were pro- vided by the statistical analysis of simulation outcomes water resources management planning in Kaidu-Konqi The developed STIP model was applied to a real case of watershed, where three scenarios with different water re- sources management policies were analyzed. The results indicated that water shortage mainly occurred in agri- culture, ecology and forestry sectors. In comparison, the water demand from municipality, industry and stock- breeding sectors can be satisfied due to their lower consumptions and higher economic values. Different policies for ecological water allocation can result in varied system benefits, and can help to identify desired water allocation plans with a maximum economic benefit and a minimum risk of system disruption under uncertainty.
基金Supported by the National Basic Research Program of China(2012CB720500)the National High Technology Research and Development Program of China(2013AA040702)
文摘This paper introduces a practical solving scheme of gradetransition trajectory optimization(GTTO) problems under typical certificate-checking–updating framework. Due to complicated kinetics of polymerization,differential/algebraic equations(DAEs) always cause great computational burden and system non-linearity usually makes GTTO non-convex bearing multiple optima. Therefore, coupled with the three-stage decomposition model, a three-section algorithm of dynamic programming(TSDP) is proposed based on the general iteration mechanism of iterative programming(IDP) and incorporated with adaptivegrid allocation scheme and heuristic modifications. The algorithm iteratively performs dynamic programming with heuristic modifications under constant calculation loads and adaptively allocates the valued computational resources to the regions that can further improve the optimality under the guidance of local error estimates. TSDP is finally compared with IDP and interior point method(IP) to verify its efficiency of computation.
文摘Aim: We devised a self-care supporting program targeting patients with early stages of secondary lower-limb lymphedema. The program incorporates “Simple exercises to replace lymphatic drainage” based on lymphatic flow. The purpose of this study was to consider the feasibility of continuing this program. Methods: The participants were patients in the early stages of secondary lower-limb lymphedema after gynecological cancer surgery and lymphedema therapists with more than five years of experience. Patients continued self-care at home after being briefed on the program, and they were analyzed on their self-care continuity status one month later based on a self-administered questionnaire survey and self-care notes. We interviewed the lymphedema therapists about this program to discuss the feasibility of continuing it and obtain feedback. Results: The patients who participated in the study were six women who underwent surgery with lymph node dissection for gynecological cancer. The therapists were five nurses and one occupational therapist. The patient understood the importance of all items in the self-care. “Observation,” “Touching,” and “Skin care” were relatively easy to continue. “Lymph drainage” and “Exercise” were continued with “Simple exercises to replace lymphatic drainage”. “Other exercises” were able to continue by adding distance and time to daily activities. Furthermore, “Measurement” and “Recording” became a burden and were difficult to continue. Nonetheless, this program was generally approved by the lymphedema therapists. They also pointed out the content and format of the self-care notes as improvements. Conclusions: We found that the self-care supporting program that incorporated “Simple exercises to replace lymphatic drainage” might be feasible to continue self-care for patients with early stages of secondary lower-limb lymphedema. Furthermore, we found that we needed to improve the “Measurement” and “Recording” sections of this program.
基金the Shanghai Application Material(AM) Research Foundation (No.08700740700)
文摘An optimization design technique to obtain global solution for a two-stage operational amplifier(op-amp) with frequency compensation is presented.This frequency compensation technique can adjust the equivalent resistance to guarantee that the phase margin is stable even though circumstance temperature varies.Geometric programming is used to optimize the component values and transistor dimensions.It is used in this analog integrated circuit design to calculate these parameters automatically.This globally optimal amplifier obtains minimum power while other specifications are fulfilled.
文摘该文提出一种考虑故障后多阶段恢复的智能软开关(soft open point,SOP)柔性互联配电网(flexible interconnected distribution network,FIDN)可靠性评估方法,其特征在于将基于SOP的FIDN网络拓扑状态通过优化过程的决策变量显式表达,建立面向FIDN可靠性评估的混合整数线性规划模型,从而实现FIDN可靠性评估。首先,分析FIDN多阶段恢复过程,提出一种多阶段恢复过程解耦建模的FIDN可靠性评估框架;然后,基于SOP正常运行和不同故障下的外特性,建立面向可靠性评估的SOP等效模型,构建FIDN节点-支路状态关联模型以实现网络拓扑状态显式化;之后,考虑SOP转供功率约束及短时过载能力,建立不同策略下的SOP快速转供模型;在此基础上,考虑SOP快速转供、故障点上游恢复、联络开关切换转供、孤岛运行等多阶段恢复过程,建立面向FIDN可靠性评估的混合整数线性规划模型;最后,在改进的37节点系统上验证所提方法的有效性。
基金part of the Program of "Study on Optimization and Supply-side Reliability of Oil Product Supply Chain Logistics System" funded under the National Natural Science Foundation of China, Grant Number 51874325
文摘Oil and gas pipeline networks are a key link in the coordinated development of oil and gas both upstream and downstream.To improve the reliability and safety of the oil and gas pipeline network, inspections are implemented to minimize the risk of leakage, spill and theft, as well as documenting actual incidents. In recent years, unmanned aerial vehicles have been recognized as a promising option for inspection due to their high efficiency. However, the integrated optimization of unmanned aerial vehicle inspection for oil and gas pipeline networks, including physical feasibility, the performance of mission, cooperation, real-time implementation and three-dimensional(3-D) space, is a strategic problem due to its large-scale,complexity as well as the need for efficiency. In this work, a novel mixed-integer nonlinear programming model is proposed that takes into account the constraints of the mission scenario and the safety performance of unmanned aerial vehicles. To minimize the total length of the inspection path, the model is solved by a two-stage solution method. Finally, a virtual pipeline network and a practical pipeline network are set as two examples to demonstrate the performance of the optimization schemes. Moreover, compared with the traditional genetic algorithm and simulated annealing algorithm, the self-adaptive genetic simulated annealing algorithm proposed in this paper provides strong stability.
文摘We present an approximation-exact penalty function method for solving the single stage stochastic programming problem with continuous random variable. The original problem is transformed into a determinate nonlinear programming problem with a discrete random variable sequence, which is obtained by some discrete method. We construct an exact penalty function and obtain an unconstrained optimization. It avoids the difficulty in solution by the rapid growing of the number of constraints for discrete precision. Under lenient conditions, we prove the equivalence of the minimum solution of penalty function and the solution of the determinate programming, and prove that the solution sequences of the discrete problem converge to a solution to the original problem.
文摘In this study, an interval probability-based inexact two-stage stochastic (IP-ITSP) model is developed for environmental pollutants control and greenhouse gas (GHG) emissions reduction management in regional energy system under uncertainties. In the IP-ITSP model, methods of interval probability, interval-parameter programming (IPP) and two-stage stochastic programming (TSP) are introduced into an integer programming framework;the developed model can tackle uncertainties described in terms of interval values and interval probability distributions. The developed model is applied to a case of planning GHG -emission mitigation in a regional electricity system, demonstrating that IP-ITSP is applicable to reflecting complexities of multi-uncertainty, and capable of addressing the problem of GHG-emission reduction. 4 scenarios corresponding to different GHG -emission mitigation levels are examined;the results indicates that the model could help decision makers identify desired GHG mitigation policies under various economic costs and environmental requirements.
文摘Having lectured in some universities and polytechnics in Nigeria, the researchers observed problems in course allocations. There are no lay-down techniques on how courses should be allocated with respect to the minimum and maximum credit a lecturer should carry in a semester. Many lecturers were overloaded while others were under-loaded. For this reason, dynamic programming model was developed for allocating courses among lecturers in the Nigerian universities using the Department of Statistics, Federal University of Technology Owerri, as a case study. From our analysis, we observed that among all the optimal allocations discovered in the study, the best optimal allocation policy was achieved at the point (1, 2, 1, 2). Allocation of courses in this order will yield an optimal credit hour of 12 per lecturer per semester.
基金Supported by Grants from the"Yucai"Research Program of Changhai Hospital
文摘AIM:To investigate if and how programmed death type-1(PD-1)expression affects the natural course of hepatitis B virus(HBV)infection. METHODS:Sixty-four patients in different natural stages of chronic HBV infection were enrolled in this study.PD-1 expression in total T cells was detected by flow cytometry.Levels of total CD8+T cell responses and proliferation in relation to PD-1 expression levels were analyzed with intracellular staining and PD-1/ PD-L1 blockage. RESULTS:The PD-1 expression in T cells was dynamically changed during the natural course of chronic HBV infection,did not significantly increase in the immune tolerance phase,and returned to normal in the inactive virus carrier stage.Blockage of the PD-1/PD-L1 pathway could not affect the T-cell response in the immune tolerance and inactive virus carrier stages of chronic HBV infection.However,it could significantly restore the T-cell response in the immune clearance stage of chronic HBV infection.Furthermore,the PD-1 expression level in T cells was associated with the alanine aminotransferase level during the immune clearance stage of chronic HBV infection. CONCLUSION:The PD-l/PD-L1 pathway plays a different role in T-cell response during the natural course of chronic HBV infection.
