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Values of the Times of Marx's Theory of Science and Technology Progress and Utilization of Natural Resources 被引量:1
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作者 Jiefang ZHU 《Meteorological and Environmental Research》 CAS 2020年第4期78-82,共5页
Marx's theory of scientific and technological progress and utilization of natural resources is an indispensable and important part of Marx's economic theory.To realize the harmonious unification of man and nat... Marx's theory of scientific and technological progress and utilization of natural resources is an indispensable and important part of Marx's economic theory.To realize the harmonious unification of man and nature,man must correctly understand the effect of scientific and technological progress on the use of natural resources,fundamentally solve the problem that scientific and technological progress cannot replace the position of natural resources in economic development,and objectively evaluate the relationship between human power and the power of nature.Grasping and comprehending the scientific connotation of Marx's theory of scientific and technological progress and utilization of natural resources has a very important theoretical value and practical significance for saving and effectively using natural resources and building an environment-friendly society. 展开更多
关键词 Scientific and technological progress Utilization of natural resources values of the times
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Influence of Initial Value of Transient Time Step on Numerical Simulation of Blow Molding Balloon 被引量:3
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作者 Jinyao Bian Guobao Jin +1 位作者 Peng Qin Guanghui Dai 《American Journal of Computational Mathematics》 2020年第2期266-274,共9页
The correlation between the initial time value of transient iterative parameters and the blowing pressure in the numerical simulation process of blowing balloon is investigated by POLYFLOW. The results show that: 1) A... The correlation between the initial time value of transient iterative parameters and the blowing pressure in the numerical simulation process of blowing balloon is investigated by POLYFLOW. The results show that: 1) As the blow molding pressure increases, the boundary value of the iterative time step decreases rapidly at first and then slowly. At the end of the first step of iterative calculation for each boundary value, the balloon parison is in the mold core cavity. 2) If the initial time value of transient iterative parameters is smaller than the boundary value of the iterative time step, the balloon parison is still in the mold core cavity at the end of the first iteration. However, if the iterative calculation continues, the calculation process may be interrupted when the time step is smaller than the initial time value of the transient iterative parameters, which makes the blow molding simulation of balloon unable to continue. 3) It is suggested that the initial time value of transient iterative parameters is one order of magnitude smaller than the boundary value of the iterative time step to complete smoothly the simulation of blow molding balloon. 展开更多
关键词 Transient Iteration time-Step Initial time Value Balloon Forming Blow Molding Pressure
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A Note on the Expectation Value of Time
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作者 Yigal Ronen 《Journal of Modern Physics》 2016年第6期459-460,共2页
In this note, the expectation value of time based on quantum mechanics formalism is derived. It is found that the expectation value of time does not depend on space.
关键词 Expectation Value of time Space Dependence time Operator
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Development potential of the Northeast Passage based on a multinomial-logit-based stochastic user equilibrium model
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作者 ZHOU Xuelian HU Maixiu 《Advances in Polar Science》 CSCD 2023年第1期45-55,共11页
We developed a multinomial-logit-based stochastic user equilibrium(MNL SUE)model incorporating time value of cargo to investigate future proportions of cargo flow through the Northeast Passage(NEP)and the Suez Canal R... We developed a multinomial-logit-based stochastic user equilibrium(MNL SUE)model incorporating time value of cargo to investigate future proportions of cargo flow through the Northeast Passage(NEP)and the Suez Canal Route between representative ports.We studied navigation during the ice-free and ice-covered seasons using sea ice projections for 2070 based on 1991–2021 NEP ice data.Sailing distance and time between selected ports are lower via the NEP than the Suez Canal Route.Under the scenario of year-round operation of the NEP,the proportion of cargo flow through the NEP is estimated to be 68.5%,which represents considerable commercial potential.Proportions are higher for the ice-free season and for ports at high latitudes.We also assessed flow under different scenarios.Under the scenario of fuel price increase,proportion of flow through the NEP in the ice-covered season is expected to increase.If time value is ignored,flow through the NEP is expected to increase all year round.If shippers become more cost-conscious,flow through the NEP is also expected to increase. 展开更多
关键词 Northeast Passage multinomial-logit-based stochastic user equilibrium(MNL SUE) time value scenario analysis
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How does trip frequency distort time value to impact congestion charging schemes?
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作者 Maosheng Li Hangcong Li 《Transportation Safety and Environment》 EI 2024年第1期22-39,共18页
A notable feature of a city or region with close economic and social connections with its neighbours is its highly mixed local and external traffic,and in some cases the external traffic volume is almost as high as th... A notable feature of a city or region with close economic and social connections with its neighbours is its highly mixed local and external traffic,and in some cases the external traffic volume is almost as high as that of local traffic.Whilst local traffic volume may be largely made up of the same regular local commuters making frequent trips,external traffic from outside of the city(region)may not be the same people making regular trips to/from the city.However,from a large pool of people making infrequent trips to/from the city,the existence of external traffic is proven by data from the licence plate recognition system of road vehicles in Changde,China.The function of value of time correlated with the income/wage rate and trip frequency is exploited and verified statistically.The time value distorted by trip frequency is defined as perceived time value(PTV),which also influences the way travellers perceive any travel impedance such as congestion delay and toll charges.This paper analyses the price of anarchy(POA)when explicitly considering the travel frequency of the trip-makers and their PTV,and compares with previous analysis without considering travel frequency.We show that when travel frequency is considered,the optimal toll of congested road pricing schemes which converts road traffic flow from user equilibrium into system optimization is much lower than that without considering travel frequency.The cost of licence plate auction cannot be treated as a congestion toll,which is only a threshold of vehicle ownership.That travellers choose routes by PTV rather than TV(time value)is proven by an example of Heishipu Bridge in Changsha,Hunan Province,China. 展开更多
关键词 road congestion charging travel frequency perceived time value road traffic impedance price of anarchy
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A Study on Marine Region Carrying Capacity and Eco-compensation 被引量:4
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作者 MA Caihua YOU Kui +2 位作者 MA Weiwei XIE Jun LI Fengqi 《Journal of Ocean University of China》 SCIE CAS 2012年第2期253-256,共4页
With the using up of land resources, people are beginning to pay attention to the exploitation of the ocean and the use of marine resources is becoming more and more intense. Whether and how the ocean can be sustainab... With the using up of land resources, people are beginning to pay attention to the exploitation of the ocean and the use of marine resources is becoming more and more intense. Whether and how the ocean can be sustainably exploited as it is being exploited is an academic hot topic. This question is addressed in this paper based on the theories of carrying capacity of a marine region and marine eco-compensation, and the amount of the loss is calculated by the method of Time Value of Capital. This thesis covers the study of eco-compensation between two specific subjects with clear compensation objects, and as a defined approach and standard, the proposed method has good operability and positive practical significance in the good use of the ocean. 展开更多
关键词 carrying capacity of marine region marine eco-compensation time value of capital
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A Double Shot Noise Process and Its Application in Insurance 被引量:2
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作者 Angelos Dassios Jiwook Jang 《Journal of Mathematics and System Science》 2012年第2期82-93,共12页
The authors consider a compound Cox model of insurance risk with the additional economic assumption of a positive interest rate. As the authors note a duality result relating a compound Cox model of insurance risk wit... The authors consider a compound Cox model of insurance risk with the additional economic assumption of a positive interest rate. As the authors note a duality result relating a compound Cox model of insurance risk with a positive interest rate and a double shot noise process, the authors analyze a double shot noise process systematically for its theoretical distributional properties, based on the piecewise deterministic Markov process theory, and the martingale methodology. The authors also obtain the moments of aggregate accumulated/discounted claims where the claim arrival process follows a Cox process with shot noise intensity. Removing the parameters in a double shot noise process gradually, the authors show that it becomes a compound Cox process with shot noise intensity, a single shot noise process and a compound Poisson process. Numerical comparisons are shown between the moments (i.e. means and variances) of a compound Poisson model and their counterparts of a compound Cox model with/without considering a positive interest rate. For that purpose, the authors assume that claim sizes and primary event sizes follow an exponential distribution, respectively. 展开更多
关键词 Double shot noise process a Cox process stochastic intensity and time value of claims aggregate accumulated/discounted claims.
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Research on Leak Location of Liquid-filled Pipe Based on Frequency Dispersion Characteristics
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作者 Lijun XIONG Ping LU +1 位作者 Yun YANG Li LI 《Mechanical Engineering Science》 2021年第1期19-27,共9页
Due to the material problems and force majeure factors,the leakage will be occurred on the liquid-filled pipe resulting in waste of resources,environmental pollution and even endangering safety.Acoustic wave detection... Due to the material problems and force majeure factors,the leakage will be occurred on the liquid-filled pipe resulting in waste of resources,environmental pollution and even endangering safety.Acoustic wave detection technology is widely used in buried pipeline leak detection,this technology mainly uses the wave(n=0,s=1)in the pipeline acoustic wave to locate the leak.When the leakage acoustic signal propagates along the liquid-filled pipe,the frequency dispersion characteristics can be obtained by wavelet decomposition.And there is a time delay(time difference)value between the leaky acoustic signals collected by the sensors at both ends of the leak.The outputs show that the results obtained by wavelet decomposition are in good agreement with the theoretical calculation results.Based on the obtained dispersion relation,the time delay values at different characteristic frequencies are analyzed by the cross-correlation method,and the leak location accuracy is discussed.This research content provides theoretical support and engineering application guidance for pipe leakage location technology. 展开更多
关键词 Liquid-filled pipe Frequency dispersion characteristics Leak location time delay estimation value
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Evaluation and Effectiveness of Reallocating Traffic Signal Timing at Corridors with High Freight Volume
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作者 Ijeoma Ihuoma-Walter Celeste Chavis Adewole Oladele 《Journal of Architectural Environment & Structural Engineering Research》 2022年第2期25-33,共9页
The COVID-19 pandemic drastically altered traffic patterns across the globe.With more people staying at home and relying on delivery services,there was a reduction in passenger car traffic but an increase in freight t... The COVID-19 pandemic drastically altered traffic patterns across the globe.With more people staying at home and relying on delivery services,there was a reduction in passenger car traffic but an increase in freight traffic.This study investigates the changes in traffic volume and mode splits during the COVID-19 pandemic at the intersection of Broening Highway and Holabird Avenues and investigates traffic signal reallocation strategies that account for the changes in traffic.This study considers morning peak traffic volumes before and during COVID.A methodology was developed to evaluate and measure freight volumes and emissions.From the literature,the cost per kilogram of CO,VOC,and NOx was$5.85,$3,37,and$12.53,respectively.The intersection operated at a level of service(LOS)of C both pre-COVID and during COVID.Traffic volume decreased by 24.3%during COVID at the study location;car volumes declined by 50%,and truck volumes increased by 130%.The total rate of emissions decreased by 22.6%. 展开更多
关键词 Multi-modal transportation Signalized intersection FREIGHT Vehicle and persons delay COVID Value of time
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INVENTORY REPLENISHMENT POLICY FOR THE DECISION MAKER WITH PRESENT-BIASED PREFERENCE AND TIME-INCONSISTENCY UNDER INFLATION 被引量:1
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作者 Yongwu Zhou Zhaozhan Lin 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2017年第5期628-645,共18页
Due to bounded rationality, people often rush for instantaneous gratification if the decisions involve immediate rewards, but procrastinate if the decisions involve immediate costs. Present-biased preference and time-... Due to bounded rationality, people often rush for instantaneous gratification if the decisions involve immediate rewards, but procrastinate if the decisions involve immediate costs. Present-biased preference and time-inconsistency will be more salient when people are making inter-temporal decisions to trade off rewards and costs in the future. People outweigh the present and their preference for the outcome in the furore will decline over time. Incorporating present-biased preference and time-inconsistency under quasi-hyperbolic discounting, time value of money under inflation and time-varying demand with shortages completely backlogged, we develop an inventory replenishment model for a deteriorating item. Inventory replenishment policies that benefit the decision maker are as follows. With the increase of time-inconsistency, one can increase ordering number and decrease fraction of shortages; with the increase of hazard rate within an upper limit, one can increase ordering number and decrease fraction of shortage; with the increase of compounded discount rate, one can increase ordering number and fraction of shortage. Hyperbolic discounting increases the ordering number and decreases the final profit, and the degree of hyperbolic discounting strengthens such outcomes. As a result, the optimal policy for a decision maker is to keep as rational as possible when making inter-temporal decisions. 展开更多
关键词 Inventory replenishment time-varying demand time value of money time-inconsistency bounded rationality hyperbolic discounting
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An approach towards estimating critical value of waiting time at transit stops 被引量:1
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作者 Subhojit Roy Debasis Basu 《Journal of Traffic and Transportation Engineering(English Edition)》 CSCD 2021年第2期257-266,共10页
Waiting time at transit stops is found to be an influential policy variable for a passenger’s decision on whether to undertake a given transit service. With regard to policy framework for improvement of operational s... Waiting time at transit stops is found to be an influential policy variable for a passenger’s decision on whether to undertake a given transit service. With regard to policy framework for improvement of operational service headway of a transit service and thereby its waiting time, the necessity to have knowledge on its critical value becomes inevitable. The critical value of waiting time for passengers waiting at transit stops is that duration beyond which passengers are found to be no more interested to wait for a that transit service. The paper demonstrates an approach for estimating the critical value of waiting time at urban transit stops with reference to public transport services such as city bus and shared-auto operational in Bhubaneswar, India. The critical value of waiting time is estimated from the point on cumulative distribution curve of waiting time frequency distribution, at which the maximum rate of change of the slope of curve occurs. The work assumes two positively skewed distributions such as gamma and log-normal for observed distributional pattern of waiting time. The work identifies that gamma distribution is comparatively fitting the observed data better than log-normal distribution. The study reveals that the critical value of waiting time for city bus passengers is about twice than that of shared auto passengers.Though, the study presents new information on critical values of waiting time with reference to an urban area of a developing country, it also demonstrates an experience on application of probability distribution functions for understanding distributional pattern of waiting time. 展开更多
关键词 Traffic engineering Waiting time at transit stop Critical value of waiting time Probability density function Gamma and log-normal distribution
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Maxima and sum for discrete and continuous time Gaussian processes
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作者 Yang CHEN ZhongquanTAN 《Frontiers of Mathematics in China》 SCIE CSCD 2016年第1期27-46,共20页
We study the asymptotic relation among the maximum of continuous weakly and strongly dependent stationary Gaussian process, the maximum of this process sampled at discrete time points, and the partial sum of this proc... We study the asymptotic relation among the maximum of continuous weakly and strongly dependent stationary Gaussian process, the maximum of this process sampled at discrete time points, and the partial sum of this process. It is shown that these two extreme values and the sum are asymptotically independent if the grid of the discrete time points is sufficiently sparse and the Gaussian process is weakly dependent, and asymptotically dependent if the grid points are Pickands grids or dense grids. 展开更多
关键词 Continuous time process DEPENDENCE discrete time process extreme value Gaussian process SUM
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THE SYMMETRIC POSITIVE SOLUTIONS OF 2n-ORDER BOUNDARY VALUE PROBLEMS ON TIME SCALES
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作者 Yangyang Yu Linlin Wang Yonghong Fan 《Annals of Applied Mathematics》 2016年第3期311-321,共11页
In this paper, we are concerned with the symmetric positive solutions of a 2n-order boundary value problems on time scales. By using induction principle,the symmetric form of the Green's function is established. In o... In this paper, we are concerned with the symmetric positive solutions of a 2n-order boundary value problems on time scales. By using induction principle,the symmetric form of the Green's function is established. In order to construct a necessary and sufficient condition for the existence result, the method of iterative technique will be used. As an application, an example is given to illustrate our main result. 展开更多
关键词 symmetric positive solutions boundary value problems induction principle time scales iterative technique
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MANAGING REDISTRIBUTION OF TOLL REVENUE WITH USER HETEROGENEITY 被引量:1
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作者 Shu-Xian Xu Tian-Liang Liu Hai-Jun Huang 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2014年第3期330-342,共13页
With the explicit consideration of user heterogeneity, i.e., each user has a different value of time (VOT), this paper examines the system efficiency and social equity of toll revenue redistribution in a bi-mode tra... With the explicit consideration of user heterogeneity, i.e., each user has a different value of time (VOT), this paper examines the system efficiency and social equity of toll revenue redistribution in a bi-mode transportation system. Three schemes of distributing the road toll revenue are proposed, which respectively consider efficiency, equity, as well as efficiency and equity together. With mild assumptions, we prove that the number of auto-motorists decreases and the total social cost increases with transit subsidy share when only marginal operating cost of the transit is covered by its fare. However, when average fixed cost of the transit is further covered, the total social cost is a "U" shape curve against the transit subsidy share. Numerical results show that the well designed toll revenue redistribution schemes can make the system more equitable while keeping high efficiency. With the increase of user heterogeneity, the Gini coefficient becomes larger while the total social cost goes down. 展开更多
关键词 Mode choice value of time toll revenue redistribution efficiency EQUITY
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THE BOUND OF PRICE OF ANARCHY FOR MULTI-CLASS AND MULTI-CRITERIA TRAFFIC EQUILIBRIUM PROBLEM
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作者 Kedong CHEN Daoli ZHU +1 位作者 Yihong HU Jianlin LIU 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2012年第1期77-93,共17页
In this paper, we use the variational method to study the efficiency loss of user equilibrium for the multi-class, multi-criterion traffic equilibrium with general tolls and a discrete set of value of. time. By introd... In this paper, we use the variational method to study the efficiency loss of user equilibrium for the multi-class, multi-criterion traffic equilibrium with general tolls and a discrete set of value of. time. By introducing three important parameters k1, k2, k3, we derive several bounds of price of anarchy for this problem when tolls are considered and not considered as part of the system cost, with the cost-based criterion. 展开更多
关键词 Value of time variational method price of anarchy multi-class multi-criterion traffic equilibrium
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Models of Choosing the Financial Compensation Strategy for Flight Delay
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作者 Mingliang Han 《Journal of Systems Science and Information》 2009年第3期253-259,共7页
At present, most airlines adopted generally the same amount of compensa- tion strategy when needing to provide financial compensation to all flight delay passengers. However, due to the existence of differences in tra... At present, most airlines adopted generally the same amount of compensa- tion strategy when needing to provide financial compensation to all flight delay passengers. However, due to the existence of differences in travel time value, ticket fare, as well as the expectation of compensation for flight delays, the gap between the effect of same amount of compensation and many passengers' (especially the high-value ones) expectations is large, it results in that airlines need to pay higher cost of compensation, but the total effect of compensation for passengers are not better. This paper advanced four financial com- pensation strategies for flight delays, summarized their own characteristics, and took into account the interests of both airlines and passengers, built the optimization models of the four financial compensation strategies under the restriction of the airline's compensation cost and on the goal of the maximum total effectiveness of the financial compensation to all passengers. Finally, based on the specific circumstances of the flight delays, the paper discussed the method for airline to choose the optimal financial compensation strategy through solving four models and comparing the compensation effectiveness. 展开更多
关键词 flight delay financial compensation STRATEGY MODEL time value
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