According to the basic concepts of precision and the principles of analysis of variance (ANOVA), precision types for experiments and variety comparison in regional crop trials (RCT) were studied and developed; expecte...According to the basic concepts of precision and the principles of analysis of variance (ANOVA), precision types for experiments and variety comparison in regional crop trials (RCT) were studied and developed; expected variety comparison precision (EVCP) and realized variety comparison precision (RVCP) and the corresponding statistical indexes of them were proposed. It was explained that experimental precision (EP) and variety comparison precision (VCP) are two kinds of precision of RCT; EP includes error precision and variety mean precision, which can be measured respectively by the coefficient of variation of single observation's error (CVe) and the coefficient of variation of variety mean's error (CVy); VCP includes EVCP and RVCP, which can be measured respectively by the detectable least relative difference (DLRD) and the relative least significant distance (RLSD); EP is an important factor of VCP but not identical to it; RVCP is the realization of EVCP. Besides error, experimental design and GE interaction and ANOVA model affect VCP. Several application examples for these precision indexes were presented, and the precision of regional cotton trials in the Yellow River Valley and the Changjiang Valley were investigated through the historical data of RCTs from 1980 to 1999.展开更多
The impact of initial guess and grid resolutions on the analysis and prediction has been investigated over the Indian region. For this purpose, an univariate objective analysis scheme and a primitive equation barotrop...The impact of initial guess and grid resolutions on the analysis and prediction has been investigated over the Indian region. For this purpose, an univariate objective analysis scheme and a primitive equation barotropic model have been used. The impact of initial guess and the resolutions on analysis and prediction is discussed.展开更多
Bijie Experimental Region takes the ecological construction as the guarantee and takes population control as the key,to promote development-oriented poverty reduction and explore benign interaction between development...Bijie Experimental Region takes the ecological construction as the guarantee and takes population control as the key,to promote development-oriented poverty reduction and explore benign interaction between development-oriented poverty reduction and ecological construction and population control.Development-oriented poverty reduction model includes combination of raising crops and livestock,coordinated development of multiple wealth sources,transferring labor,and partner assistance;ecological construction model includes"Five sons passed imperial examinations",desertification control,agricultural circular economy,and project promotion;population control models includes human-land linkage,combination of favorable policies and propaganda and education,and combination of ambition arousing and education promotion.展开更多
Water hammer phenomenon involves the transformation of kinetic energy in pressure energy, this transformation occurs as the fluid conditions change inside the pipe in quite a short time. Industry requires to affront f...Water hammer phenomenon involves the transformation of kinetic energy in pressure energy, this transformation occurs as the fluid conditions change inside the pipe in quite a short time. Industry requires to affront frequent flow interruptions in pipe systems due to the closing of valves or stopping of pumping equipment. This phenomenon can initiate serious damages like destruction of the pipe system involving leakage of the working fluid to the environment. If the system operates in a fragile environment, as in cold regions, concern about the consequences of leakage increases due to the variation of physical properties of fluid as well as the pipe material as a function of the temperature. Water hammer effects can be controlled focusing efforts on reducing the pressure increment that takes place once the phenomenon is presented. Some methods try to reduce the time of closure or the rate of change before the closure using special valves, others install additional elements to absorb the pressure surge and dissipate energy, others install relief valves to release the pressure, and others try to split the problem is smaller sections by installing check valves with dashpot or non-return valves. Splitting the pipeline into shorter sections is often used to help preventing the pipeline length of water falling back after a pump stops. In this paper the numerical results of maximum and minimum pressure values at both ends of a closed section are compared to experimental data. The numerical results follow the experimental trends.展开更多
Power industry is one of the key fields for energy conservation and emissions reduction (ECER) in China. In order to achieve the nation's overall energy consumption target and pollutant emission target set by the ...Power industry is one of the key fields for energy conservation and emissions reduction (ECER) in China. In order to achieve the nation's overall energy consumption target and pollutant emission target set by the 11th Five-Year Plan, to build the resource-conservation and environment-friendly society during the 11th Five-Year Plan period (2006-2010), it is crucial to implement the policy of "Large (units) In and Small (units) Out (LISO)" (i.e., replacing small units with large ones) and accelerate the retirement of small thermal units. According to the statistics, the power industry has made a significant progress in SO2 emission reduction during the first half of 2007. Specifically, with 18.3% growth in power generation, the SO2 emission was reduced by 5.2% compared with the same period in 2006. By the end of July 2007, the retired small units have totaled 6950 MW, 85% of which belongs to the five major power generation groups such as Guodian and Huadian. In this article, the achievements and remaining issues in Henan, Jiangsu, Sichuan Power Companies and East China Grid Company were presented and discussed thoroughly.展开更多
文摘According to the basic concepts of precision and the principles of analysis of variance (ANOVA), precision types for experiments and variety comparison in regional crop trials (RCT) were studied and developed; expected variety comparison precision (EVCP) and realized variety comparison precision (RVCP) and the corresponding statistical indexes of them were proposed. It was explained that experimental precision (EP) and variety comparison precision (VCP) are two kinds of precision of RCT; EP includes error precision and variety mean precision, which can be measured respectively by the coefficient of variation of single observation's error (CVe) and the coefficient of variation of variety mean's error (CVy); VCP includes EVCP and RVCP, which can be measured respectively by the detectable least relative difference (DLRD) and the relative least significant distance (RLSD); EP is an important factor of VCP but not identical to it; RVCP is the realization of EVCP. Besides error, experimental design and GE interaction and ANOVA model affect VCP. Several application examples for these precision indexes were presented, and the precision of regional cotton trials in the Yellow River Valley and the Changjiang Valley were investigated through the historical data of RCTs from 1980 to 1999.
文摘The impact of initial guess and grid resolutions on the analysis and prediction has been investigated over the Indian region. For this purpose, an univariate objective analysis scheme and a primitive equation barotropic model have been used. The impact of initial guess and the resolutions on analysis and prediction is discussed.
文摘Bijie Experimental Region takes the ecological construction as the guarantee and takes population control as the key,to promote development-oriented poverty reduction and explore benign interaction between development-oriented poverty reduction and ecological construction and population control.Development-oriented poverty reduction model includes combination of raising crops and livestock,coordinated development of multiple wealth sources,transferring labor,and partner assistance;ecological construction model includes"Five sons passed imperial examinations",desertification control,agricultural circular economy,and project promotion;population control models includes human-land linkage,combination of favorable policies and propaganda and education,and combination of ambition arousing and education promotion.
文摘Water hammer phenomenon involves the transformation of kinetic energy in pressure energy, this transformation occurs as the fluid conditions change inside the pipe in quite a short time. Industry requires to affront frequent flow interruptions in pipe systems due to the closing of valves or stopping of pumping equipment. This phenomenon can initiate serious damages like destruction of the pipe system involving leakage of the working fluid to the environment. If the system operates in a fragile environment, as in cold regions, concern about the consequences of leakage increases due to the variation of physical properties of fluid as well as the pipe material as a function of the temperature. Water hammer effects can be controlled focusing efforts on reducing the pressure increment that takes place once the phenomenon is presented. Some methods try to reduce the time of closure or the rate of change before the closure using special valves, others install additional elements to absorb the pressure surge and dissipate energy, others install relief valves to release the pressure, and others try to split the problem is smaller sections by installing check valves with dashpot or non-return valves. Splitting the pipeline into shorter sections is often used to help preventing the pipeline length of water falling back after a pump stops. In this paper the numerical results of maximum and minimum pressure values at both ends of a closed section are compared to experimental data. The numerical results follow the experimental trends.
文摘Power industry is one of the key fields for energy conservation and emissions reduction (ECER) in China. In order to achieve the nation's overall energy consumption target and pollutant emission target set by the 11th Five-Year Plan, to build the resource-conservation and environment-friendly society during the 11th Five-Year Plan period (2006-2010), it is crucial to implement the policy of "Large (units) In and Small (units) Out (LISO)" (i.e., replacing small units with large ones) and accelerate the retirement of small thermal units. According to the statistics, the power industry has made a significant progress in SO2 emission reduction during the first half of 2007. Specifically, with 18.3% growth in power generation, the SO2 emission was reduced by 5.2% compared with the same period in 2006. By the end of July 2007, the retired small units have totaled 6950 MW, 85% of which belongs to the five major power generation groups such as Guodian and Huadian. In this article, the achievements and remaining issues in Henan, Jiangsu, Sichuan Power Companies and East China Grid Company were presented and discussed thoroughly.
