The fuzzy sets theory is introduced into the fatigue reliability analysis. The concepts of maximizing set and minimizing set are developed to decide the ordering value of each fuzzy number, and these values can be use...The fuzzy sets theory is introduced into the fatigue reliability analysis. The concepts of maximizing set and minimizing set are developed to decide the ordering value of each fuzzy number, and these values can be used to determine the order of the fuzzy numbers. On the basis of the works mentioned above, the membership function defining the fuzzy safety event can be calculated, and then the fuzzy reliability in the case of stress and fuzzy fatigue strength is deduced. An example is given to illustrate the method.展开更多
Here we generalize the "BBH"-asymptotic analysis to a simplified mathematical model for tho planar ferromaguets and antiferromagnets. To develop such a static theory is a necessary step for a rigorous mathem...Here we generalize the "BBH"-asymptotic analysis to a simplified mathematical model for tho planar ferromaguets and antiferromagnets. To develop such a static theory is a necessary step for a rigorous mathematical justification of dynamical laws for the magnetic vortices formally derived in [1] and [2].展开更多
The issues of solvability and construction of a solution of the Fredholm integral equation of the first kind are considered. It is done by immersing the original problem into solving an extremal problem in Hilbert spa...The issues of solvability and construction of a solution of the Fredholm integral equation of the first kind are considered. It is done by immersing the original problem into solving an extremal problem in Hilbert space. Necessary and sufficient conditions for the existence of a solution are obtained. A method of constructing a solution of the Fredholm integral equation of the first kind is developed. A constructive theory of solvability and construction of a solution to a boundary value problem of a linear integrodifferential equation with a distributed delay in control, generated by the Fredholm integral equation of the first kind, has been created.展开更多
To treat resistant Escherichia coli infection in chicks, Ampicillin was stabilized with a synthetic aluminum-magnesium silicate (AMS) to prolong its bioavailability. Its dose was also reduced to minimize adverse side ...To treat resistant Escherichia coli infection in chicks, Ampicillin was stabilized with a synthetic aluminum-magnesium silicate (AMS) to prolong its bioavailability. Its dose was also reduced to minimize adverse side effects. Vitamins A, C, E and Selenium levels in the chicks’ feeds were increased to enhance immune response of the chicks. E. coli coloning forming units, per ml of bile of the chicks, treated with Ampicillin and with Ampicillin in AMS, were: 228800.00 ± 90103.50 and 134500.00 ± 44937.97 at 10 mg/kg, 104400.00 ± 36024.44 and 34800.00 ± 8014.97 at 7.5 mg/kg, 198400.00 ± 129301.80 and 156800.00 ± 109392.70 at 5 mg/kg. Mean bacterial loads of the untreated groups, fed normal feed and those fed the fortified feed were 824400.00 ± 322424.80 and 534800.00 ± 277832.80. At 7.5 mg/kg. Ampicillin in the AMS, effectively (P E. coli infection in chicks, fed immune-stimulants, with the infection rate reduced by 95.8%.展开更多
Minimizing transportation time and getting optimal solutions are always considered as important factors while solving transportation problem. This paper shows a new approach for finding initial basic solution for tran...Minimizing transportation time and getting optimal solutions are always considered as important factors while solving transportation problem. This paper shows a new approach for finding initial basic solution for transportation problem which reduces cost of transportation more than any transportation method such as LCM, northwest, Vogel’s approximation and so on. This method has been illustrated by taking an example;afterwards, it compares basic initial feasible solution with other methods IBF and optimal dictate solutions such as MODI and Steppingstone method.展开更多
Open pit mining operations utilize large scale and expensive equipment. For the mines implementing shovel and truck operation system, trucks constitute a large portion of these equipment and are used for hauling the m...Open pit mining operations utilize large scale and expensive equipment. For the mines implementing shovel and truck operation system, trucks constitute a large portion of these equipment and are used for hauling the mined materials. In order to have sustainable and viable operation, these equipment need to be utilized efficiently with minimum operating cost. Maintenance cost is a significant proportion of the overall operating costs. The maintenance cost of a truck changes non-linearly depending on the type, age and truck types. A new approach based on stochastic integer programming (SIP) techniques is used for annually scheduling a fixed fleet of mining trucks in a given operation, over the life of mine (multi-year time horizon) to minimize maintenance cost. The maintenance cost data in mining usually has uncertainty caused from the variability of the operational conditions at mines. To estimate the cost, usually historic data from different operations for new mines, and/or the historic data at the operating mines are used. However, maintenance cost varies depending on road conditions, age of equipment and many other local conditions at an operation. Traditional models aim to estimate the maintenance cost as a deterministic single value and financial evaluations are based on the estimated value. However, it does not provide a confidence on the estimate. The proposed model in this study assumes the truck maintenance cost is a stochastic parameter due to the significant level of uncertainty in the data and schedules the available fleet to meet the annual production targets. The scheduling has been performed by applying both the proposed stochastic and deterministic approaches. The approach provides a distribution for the maintenance cost of the optimized equipment schedule minimizing the cost.展开更多
This paper deals with regularity properties for minimizing sequences of some integral functionals related to the nonlinear elasticity theory.Under some structural conditions,we derive that the minimizing sequence and ...This paper deals with regularity properties for minimizing sequences of some integral functionals related to the nonlinear elasticity theory.Under some structural conditions,we derive that the minimizing sequence and the derivatives of the sequences have some regularity properties by using the Ekeland variational principle.展开更多
In this paper, the authors give some applications of F-uniformly distributedsequences, which are suggested in their previous paper under the same title, in experimen-tal design, experiments with mixtures, geometric pr...In this paper, the authors give some applications of F-uniformly distributedsequences, which are suggested in their previous paper under the same title, in experimen-tal design, experiments with mixtures, geometric probability and simulation.展开更多
Let ψ be a certain set of graphs.A graph is called a minimizing graph in the set ψ if its least eigenvalue attains the minimum among all graphs in ψ.In this paper,we determine the unique minimizing graph in ψn,whe...Let ψ be a certain set of graphs.A graph is called a minimizing graph in the set ψ if its least eigenvalue attains the minimum among all graphs in ψ.In this paper,we determine the unique minimizing graph in ψn,where ψn denotes the set of connected graphs of order n with cut vertices.展开更多
AIM: To investigate the effect of the ‘‘minimizing tacrolimus' ' strategy on long-term survival of patients after liver transplantation(LT).METHODS: We conducted a retrospective study of 319 patients who rec...AIM: To investigate the effect of the ‘‘minimizing tacrolimus' ' strategy on long-term survival of patients after liver transplantation(LT).METHODS: We conducted a retrospective study of 319 patients who received LT between January 2009 and December 2011 at the First Affiliated Hospital of Zhejiang University School of Medicine. Following elimination of ineligible patients, 235 patients were included in the study. The relationship between early tacrolimus(TAC)exposure and survival period was analyzed by Kaplan Meier curves. Adverse effects related to TAC were eval-uated by the χ2 test. Routine monitoring of blood TAC concentration(TC) was performed using the PRO-TracTM Ⅱ Tacrolimus Elisa Kit(Diasorin, United States). RESULTS: Of 235 subjects enrolled in the study, 124(52.8%) experienced adverse effects due to TAC. When evaluating mean TC, the survival time of patients with a mean TC < 5 ng/mL was significantly shorter than that in the other groups(911.3 ± 131.6 d vs 1381.1 ± 66.1 d, 911.3 ± 131.6 d vs 1327.3 ± 47.8 d, 911.3 ± 131.6 d vs 1343.2 ± 83.1 d, P < 0.05), while the survival times of patients with a mean TC of 5-7, 7-10 and 10-15 ng/mL were comparable. Adverse effects due to TAC in all four groups were not significantly different. When comparing the standard deviation(SD) of TC among the groups, the survival time of patients with a SD of 2-4 was significantly longer than that in the other groups(1388.8 ± 45.4 d vs 1029.6 ± 131.3 d, 1388.8 ± 45.4 d vs 1274.9 ± 57.0 d, P < 0.05), while in patients with a SD < 2 and SD > 4, the survival time was not statistically different. Adverse effects experienced in all three groups were not statistically different. In Cox regression analysis, male patients and those with a primary diagnosis of benign disease, mean TC > 5 ng/mL and TC SD 2-4 had better outcomes.CONCLUSION: The early ‘‘minimizing tacrolimus' ' strategy with a mean TC of 5-10 ng/mL and SD of 2-4 was beneficial in terms of long-term survival after LT.展开更多
Decision makers often face the need of performance guarantee with some sufficiently high proba-bility. Such problems can be modelled using a discrete time Markov decision process (MDP) with a probabilitycriterion for ...Decision makers often face the need of performance guarantee with some sufficiently high proba-bility. Such problems can be modelled using a discrete time Markov decision process (MDP) with a probabilitycriterion for the first achieving target value. The objective is to find a policy that maximizes the probabilityof the total discounted reward exceeding a target value in the preceding stages. We show that our formula-tion cannot be described by former models with standard criteria. We provide the properties of the objectivefunctions, optimal value functions and optimal policies. An algorithm for computing the optimal policies forthe finite horizon case is given. In this stochastic stopping model, we prove that there exists an optimal deter-ministic and stationary policy and the optimality equation has a unique solution. Using perturbation analysis,we approximate general models and prove the existence of ε-optimal policy for finite state space. We give anexample for the reliability of the satellite systems using the above theory. Finally, we extend these results tomore general cases.展开更多
As there are many heavily sedimentladen rivers in China, with high sediment concentration and a large quantity of sediment load, the sedimentation problems of the reservoirs built on those rivers are so serious that t...As there are many heavily sedimentladen rivers in China, with high sediment concentration and a large quantity of sediment load, the sedimentation problems of the reservoirs built on those rivers are so serious that the amount of sediment deposited in the reservoirs is great and the rate of sedimentation is accelerated. According to the statistics, up to the end of 1981, a total amount of 11.5×109m3 of sediment were accumulated in those reservoirs, i.e. 14.2% of the total designed capacity were lost. The average annual loss in storage capacity reached 2.3 percent, being the highest in the world. Silting of impounding lakes not only has an effect on the benefits of the reservoirs and seriously threatens the life of reservoirs, but also results in many environmental problems which were not fully estimated in the planning of the reservoirs. In this paper, the situation of reservoir deposition in China are described from the following aspects: 1) the characteristics of hydrology and sediment of the rivers; 2) the seriousness of reservoir sedimentation in China; 3) problems caused by reservoir deposition; 4) the methods of minimizing sediment deposition, etc.展开更多
A WiMAX-ZigBee energy management system for green education has been developed. The system helps to resolve the disgusting environmental problems. This paper explores the concept of energy management and introduces an...A WiMAX-ZigBee energy management system for green education has been developed. The system helps to resolve the disgusting environmental problems. This paper explores the concept of energy management and introduces an Energy Management System located at campus areas. Analysis shows that 30% energy can be saved from the total energy consumption which translates to a saving of 72 thousand million kWh of energy annually. Such saving reduces 48 million tons of CO2 emission for the environment.展开更多
基金This project is supported by National Naied Science Foundation of China(59475043). Manuscript received on July 8,1999 revised m
文摘The fuzzy sets theory is introduced into the fatigue reliability analysis. The concepts of maximizing set and minimizing set are developed to decide the ordering value of each fuzzy number, and these values can be used to determine the order of the fuzzy numbers. On the basis of the works mentioned above, the membership function defining the fuzzy safety event can be calculated, and then the fuzzy reliability in the case of stress and fuzzy fatigue strength is deduced. An example is given to illustrate the method.
基金Supported by the Dean's Dissertation FellowshipSupported by a NSF grant
文摘Here we generalize the "BBH"-asymptotic analysis to a simplified mathematical model for tho planar ferromaguets and antiferromagnets. To develop such a static theory is a necessary step for a rigorous mathematical justification of dynamical laws for the magnetic vortices formally derived in [1] and [2].
文摘The issues of solvability and construction of a solution of the Fredholm integral equation of the first kind are considered. It is done by immersing the original problem into solving an extremal problem in Hilbert space. Necessary and sufficient conditions for the existence of a solution are obtained. A method of constructing a solution of the Fredholm integral equation of the first kind is developed. A constructive theory of solvability and construction of a solution to a boundary value problem of a linear integrodifferential equation with a distributed delay in control, generated by the Fredholm integral equation of the first kind, has been created.
文摘To treat resistant Escherichia coli infection in chicks, Ampicillin was stabilized with a synthetic aluminum-magnesium silicate (AMS) to prolong its bioavailability. Its dose was also reduced to minimize adverse side effects. Vitamins A, C, E and Selenium levels in the chicks’ feeds were increased to enhance immune response of the chicks. E. coli coloning forming units, per ml of bile of the chicks, treated with Ampicillin and with Ampicillin in AMS, were: 228800.00 ± 90103.50 and 134500.00 ± 44937.97 at 10 mg/kg, 104400.00 ± 36024.44 and 34800.00 ± 8014.97 at 7.5 mg/kg, 198400.00 ± 129301.80 and 156800.00 ± 109392.70 at 5 mg/kg. Mean bacterial loads of the untreated groups, fed normal feed and those fed the fortified feed were 824400.00 ± 322424.80 and 534800.00 ± 277832.80. At 7.5 mg/kg. Ampicillin in the AMS, effectively (P E. coli infection in chicks, fed immune-stimulants, with the infection rate reduced by 95.8%.
文摘Minimizing transportation time and getting optimal solutions are always considered as important factors while solving transportation problem. This paper shows a new approach for finding initial basic solution for transportation problem which reduces cost of transportation more than any transportation method such as LCM, northwest, Vogel’s approximation and so on. This method has been illustrated by taking an example;afterwards, it compares basic initial feasible solution with other methods IBF and optimal dictate solutions such as MODI and Steppingstone method.
文摘Open pit mining operations utilize large scale and expensive equipment. For the mines implementing shovel and truck operation system, trucks constitute a large portion of these equipment and are used for hauling the mined materials. In order to have sustainable and viable operation, these equipment need to be utilized efficiently with minimum operating cost. Maintenance cost is a significant proportion of the overall operating costs. The maintenance cost of a truck changes non-linearly depending on the type, age and truck types. A new approach based on stochastic integer programming (SIP) techniques is used for annually scheduling a fixed fleet of mining trucks in a given operation, over the life of mine (multi-year time horizon) to minimize maintenance cost. The maintenance cost data in mining usually has uncertainty caused from the variability of the operational conditions at mines. To estimate the cost, usually historic data from different operations for new mines, and/or the historic data at the operating mines are used. However, maintenance cost varies depending on road conditions, age of equipment and many other local conditions at an operation. Traditional models aim to estimate the maintenance cost as a deterministic single value and financial evaluations are based on the estimated value. However, it does not provide a confidence on the estimate. The proposed model in this study assumes the truck maintenance cost is a stochastic parameter due to the significant level of uncertainty in the data and schedules the available fleet to meet the annual production targets. The scheduling has been performed by applying both the proposed stochastic and deterministic approaches. The approach provides a distribution for the maintenance cost of the optimized equipment schedule minimizing the cost.
基金supported by National Natural Science Foundation of China(Grant No.12071021)Natural Science Foundation of Hebei Province(Grant No.A2019201120)+4 种基金the Key Science and Technology Project of Higher School of Hebei Province(Grant No.ZD2021307)supported by the Postgraduate Innovation Project of Hebei Province(Grant No.CXZZSS2020005)supported by Natural Science Foundation of Hebei Province(Grant No.A2018201285)Science and Technology Project of Hebei Education Department(Grant No.QN2020145)Research Funds of Hebei University(Grant No.8012605)。
文摘This paper deals with regularity properties for minimizing sequences of some integral functionals related to the nonlinear elasticity theory.Under some structural conditions,we derive that the minimizing sequence and the derivatives of the sequences have some regularity properties by using the Ekeland variational principle.
基金This work was supported by The Chinesse National Science Fund and Academia Sinics.
文摘In this paper, the authors give some applications of F-uniformly distributedsequences, which are suggested in their previous paper under the same title, in experimen-tal design, experiments with mixtures, geometric probability and simulation.
基金Supported by the Supported by the National Natural Science Foundation of China (Grant No. 11071002)Key Project of Chinese Ministry of Education (Grant No. 210091)+4 种基金Anhui Provincial Natural Science Foundation(Grant No. 10040606Y33)Anhui University Innovation Team Project (Grant No. KJTD001B)Project of Anhui Province for Young Teachers Research Support in Universities (Grant No. 2008JQl021)Project of Anhui Province for Excellent Young Talents in Universities (Grant No. 2009SQRZ017ZD)the Natural Science Foundation of Department of Education of Anhui Province (Grant No. KJ2010B136)
文摘Let ψ be a certain set of graphs.A graph is called a minimizing graph in the set ψ if its least eigenvalue attains the minimum among all graphs in ψ.In this paper,we determine the unique minimizing graph in ψn,where ψn denotes the set of connected graphs of order n with cut vertices.
基金Supported by National S and T Major Program,No.2012 ZX10002004National Natural Science Foundation of China,No.81373160 and No.81302074
文摘AIM: To investigate the effect of the ‘‘minimizing tacrolimus' ' strategy on long-term survival of patients after liver transplantation(LT).METHODS: We conducted a retrospective study of 319 patients who received LT between January 2009 and December 2011 at the First Affiliated Hospital of Zhejiang University School of Medicine. Following elimination of ineligible patients, 235 patients were included in the study. The relationship between early tacrolimus(TAC)exposure and survival period was analyzed by Kaplan Meier curves. Adverse effects related to TAC were eval-uated by the χ2 test. Routine monitoring of blood TAC concentration(TC) was performed using the PRO-TracTM Ⅱ Tacrolimus Elisa Kit(Diasorin, United States). RESULTS: Of 235 subjects enrolled in the study, 124(52.8%) experienced adverse effects due to TAC. When evaluating mean TC, the survival time of patients with a mean TC < 5 ng/mL was significantly shorter than that in the other groups(911.3 ± 131.6 d vs 1381.1 ± 66.1 d, 911.3 ± 131.6 d vs 1327.3 ± 47.8 d, 911.3 ± 131.6 d vs 1343.2 ± 83.1 d, P < 0.05), while the survival times of patients with a mean TC of 5-7, 7-10 and 10-15 ng/mL were comparable. Adverse effects due to TAC in all four groups were not significantly different. When comparing the standard deviation(SD) of TC among the groups, the survival time of patients with a SD of 2-4 was significantly longer than that in the other groups(1388.8 ± 45.4 d vs 1029.6 ± 131.3 d, 1388.8 ± 45.4 d vs 1274.9 ± 57.0 d, P < 0.05), while in patients with a SD < 2 and SD > 4, the survival time was not statistically different. Adverse effects experienced in all three groups were not statistically different. In Cox regression analysis, male patients and those with a primary diagnosis of benign disease, mean TC > 5 ng/mL and TC SD 2-4 had better outcomes.CONCLUSION: The early ‘‘minimizing tacrolimus' ' strategy with a mean TC of 5-10 ng/mL and SD of 2-4 was beneficial in terms of long-term survival after LT.
基金We thank the referees for their valuable comments and suggestions.This work was supported by the National Natural Science Foundation of China(Grant No.19871046).
文摘Decision makers often face the need of performance guarantee with some sufficiently high proba-bility. Such problems can be modelled using a discrete time Markov decision process (MDP) with a probabilitycriterion for the first achieving target value. The objective is to find a policy that maximizes the probabilityof the total discounted reward exceeding a target value in the preceding stages. We show that our formula-tion cannot be described by former models with standard criteria. We provide the properties of the objectivefunctions, optimal value functions and optimal policies. An algorithm for computing the optimal policies forthe finite horizon case is given. In this stochastic stopping model, we prove that there exists an optimal deter-ministic and stationary policy and the optimality equation has a unique solution. Using perturbation analysis,we approximate general models and prove the existence of ε-optimal policy for finite state space. We give anexample for the reliability of the satellite systems using the above theory. Finally, we extend these results tomore general cases.
文摘As there are many heavily sedimentladen rivers in China, with high sediment concentration and a large quantity of sediment load, the sedimentation problems of the reservoirs built on those rivers are so serious that the amount of sediment deposited in the reservoirs is great and the rate of sedimentation is accelerated. According to the statistics, up to the end of 1981, a total amount of 11.5×109m3 of sediment were accumulated in those reservoirs, i.e. 14.2% of the total designed capacity were lost. The average annual loss in storage capacity reached 2.3 percent, being the highest in the world. Silting of impounding lakes not only has an effect on the benefits of the reservoirs and seriously threatens the life of reservoirs, but also results in many environmental problems which were not fully estimated in the planning of the reservoirs. In this paper, the situation of reservoir deposition in China are described from the following aspects: 1) the characteristics of hydrology and sediment of the rivers; 2) the seriousness of reservoir sedimentation in China; 3) problems caused by reservoir deposition; 4) the methods of minimizing sediment deposition, etc.
文摘A WiMAX-ZigBee energy management system for green education has been developed. The system helps to resolve the disgusting environmental problems. This paper explores the concept of energy management and introduces an Energy Management System located at campus areas. Analysis shows that 30% energy can be saved from the total energy consumption which translates to a saving of 72 thousand million kWh of energy annually. Such saving reduces 48 million tons of CO2 emission for the environment.