In the study of warm clouds,there are many outstanding questions.Cloud droplet size distributions are much wider,and warm rain is initiated in a shorter time and with a shallower cloud depth than theoretical expectati...In the study of warm clouds,there are many outstanding questions.Cloud droplet size distributions are much wider,and warm rain is initiated in a shorter time and with a shallower cloud depth than theoretical expectations.This review summarizes the studies related to the effects of turbulent fluctuations and turbulent entrainment-mixing on the broadening of droplet size distributions and warm rain initiation,including observational,laboratorial,numerical,and theoretical achievements.Particular attention is paid to studies by Chinese scientists since the 1950s,since most results have been published in Chinese.The review reveals that high-resolution observations and simulations,and laboratory experiments,are needed because knowledge of the detailed physical processes involved in the effects of turbulence and entrainment-mixing on cloud microphysics still remains elusive.The effects of turbulent fluctuations and entrainment-mixing processes have been unrealistically separated in most theoretical studies.They could be unified by further advancement of a systems theory into a predictive theory.Developing parameterizations for the effects of fluctuations and entrainment-mixing processes is still in its infancy,and more studies are warranted.展开更多
Uncertainties in engineering design may lead to low reliable solutions that also exhibit high sensitivity to uncontrollable variations. In addition, there often exist several conflicting objectives and constraints in ...Uncertainties in engineering design may lead to low reliable solutions that also exhibit high sensitivity to uncontrollable variations. In addition, there often exist several conflicting objectives and constraints in various design environments. In order to obtain solutions that are not only "multi-objectively" optimal, but also reliable and robust, a probabilistic optimization method was presented by integrating six sigma philosophy and multi-objective genetic algorithm. With this method, multi-objective genetic algorithm was adopted to obtain the global Pareto solutions, and six sigma method was used to improve the reliability and robustness of those optimal solutions. Two engineering design problems were provided as examples to illustrate the proposed method.展开更多
Dynamic running law of the hydraulic driving system decides the hoisting cage velocity curve in a hoisting cycle and is decided by the characteristic of the hydraulic driving system and by the operating speed of hoist...Dynamic running law of the hydraulic driving system decides the hoisting cage velocity curve in a hoisting cycle and is decided by the characteristic of the hydraulic driving system and by the operating speed of hoist driver. The paper studies the dynamic running law of hydraulic driving system, analyses the influence of driver operating speed on the dynamic running characteristic, and points out the reasonable driver operating speed to control the dynamic stress in rope and to reduce the oscillation of rope system.展开更多
基金supported by the National Key Research and Development Program of China[grant number 2017YFA060 4000]the China Meteorological Administration Special Public Welfare Research Fund[grant number GYHY201406001]+5 种基金the National Natural Science Foundation of China(NSFC)[grant number 91537108]the Natural Science Foundation of Jiangsu Province,China[grant number BK20160041]the U.S.Department of Energy’s BER Atmospheric System Research Program[grant number DE-SC00112704]the Six Talent Peak Project in Jiangsu,China[grant number 2015-JY-011]the 333 High-level Talents Training Project in Jiangsu[grant number BRA2016424]the NSFC[grant number 41305120]
文摘In the study of warm clouds,there are many outstanding questions.Cloud droplet size distributions are much wider,and warm rain is initiated in a shorter time and with a shallower cloud depth than theoretical expectations.This review summarizes the studies related to the effects of turbulent fluctuations and turbulent entrainment-mixing on the broadening of droplet size distributions and warm rain initiation,including observational,laboratorial,numerical,and theoretical achievements.Particular attention is paid to studies by Chinese scientists since the 1950s,since most results have been published in Chinese.The review reveals that high-resolution observations and simulations,and laboratory experiments,are needed because knowledge of the detailed physical processes involved in the effects of turbulence and entrainment-mixing on cloud microphysics still remains elusive.The effects of turbulent fluctuations and entrainment-mixing processes have been unrealistically separated in most theoretical studies.They could be unified by further advancement of a systems theory into a predictive theory.Developing parameterizations for the effects of fluctuations and entrainment-mixing processes is still in its infancy,and more studies are warranted.
基金The National Natural Science Foundation of China(No. 50475020)
文摘Uncertainties in engineering design may lead to low reliable solutions that also exhibit high sensitivity to uncontrollable variations. In addition, there often exist several conflicting objectives and constraints in various design environments. In order to obtain solutions that are not only "multi-objectively" optimal, but also reliable and robust, a probabilistic optimization method was presented by integrating six sigma philosophy and multi-objective genetic algorithm. With this method, multi-objective genetic algorithm was adopted to obtain the global Pareto solutions, and six sigma method was used to improve the reliability and robustness of those optimal solutions. Two engineering design problems were provided as examples to illustrate the proposed method.
文摘Dynamic running law of the hydraulic driving system decides the hoisting cage velocity curve in a hoisting cycle and is decided by the characteristic of the hydraulic driving system and by the operating speed of hoist driver. The paper studies the dynamic running law of hydraulic driving system, analyses the influence of driver operating speed on the dynamic running characteristic, and points out the reasonable driver operating speed to control the dynamic stress in rope and to reduce the oscillation of rope system.
