The authors use numerical model integral products in a third level forecast of synthetically multi-level analog forecast technology.This is one of the strongest points of this study,which also includes the re-ducing m...The authors use numerical model integral products in a third level forecast of synthetically multi-level analog forecast technology.This is one of the strongest points of this study,which also includes the re-ducing mean vacant-forecast rate method,which pos-sesses many advantages with regard to filtering the analog term.Moreover,the similitude degree between samples is assessed using a combination of meteorological elements,which works better than that described using a single element in earlier analog forecast studies.Based on these techniques,the authors apply the model output,air sounding,surface observation and weather map data from 1990 to 2002 to perform an analog experiment of the quasi-stationary front rainstorm.The most important re-sults are as follows:(1) The forecast successful index is 0.36,and was improved after the forecast model was re-vised.(2) The forecast precise rate (0.59) and the lost-forecast rate (0.33) are also better than those of other methods.(3) Based on the model output data,the syn-thetically multilevel analog forecast technology can pro-duce more accurate forecasts of a quasi-stationary front rainstorm.(4) Optimal analog elements reveal that trig-gering mechanisms are located in the lower troposphere while upper level systems are more important in main-taining the phase of the rainstorm.These variables should be first taken into account in operational forecasts of the quasi-stationary front rainstorm.(5) In addition,experi-ments reveal that the position of the key zone is mainly decided by the position of the system causing the heavy rainfall.展开更多
Low-tempemture stress is a major abiotic stress influencing plant growth, economic yield and quality worldwide. Precise and reliable identification and test of plant cold resistance is a foundation for exploring low-t...Low-tempemture stress is a major abiotic stress influencing plant growth, economic yield and quality worldwide. Precise and reliable identification and test of plant cold resistance is a foundation for exploring low-temperature damages, cold resistance mechanism of plants, cultivating and innovating quality cold-re- sistant germplasm resources, which is rather important for woody plants because their perennial and large-sized characteristics. Generally, most researches on plant cold-resistant physiology focused on identification and utilization of cold resistance worldwide, and a few on test methods of cold resistance, but cold resistance mechanism has been less reported. Therefore, researches on methods of identifying and testing plant resistance have achieved considerable progress, accumulated much experience and formed characteristics gradually in terms of methodology. Current methods of identifying plant cold resistance include open field/outdoor culti- vation evaluation, cold and frost damage investigation, simulated cold weather, and mathematical model forecast. And the methods of testing plant cold resistance include growth condition test, frozen index investigation, electrolyte leakage, bioelectrical impedance mapping and so on. Synthesizing the methods of identifying and testing plant cold resistance should be a key matter in the present and future researches and application of plant cold resistance physiology, improvement and in- novation of the identification and test will be an important direction of the future researches. Identification and test of plant cold resistance based on genomies, meta- bonomics and proteomics should be the new trend of the researches on physiology and ecology of plant cold resistance.展开更多
Under the current situation of the cosmetics industry,this paper compares the different technical fields of cosmetics at home and abroad and the development status of cosmetic raw materials,discusses the reasons why f...Under the current situation of the cosmetics industry,this paper compares the different technical fields of cosmetics at home and abroad and the development status of cosmetic raw materials,discusses the reasons why foreign cosmetic raw materials still occupy the majority of the country,and summarizes the development status of the number of patent applications,cosmetic safety and efficacy evaluation methods,animal substitution and in vitro evaluation technology for cosmetics,the combination of digital beauty and cosmetics and localization of testing equipment,and suggestions on the development of China’s future cosmetic original technology capabilities.展开更多
A maximum test in lieu of forcing a choice between the two dependent samples t-test and Wilcoxon signed-ranks test is proposed. The maximum test, which requires a new table of critical values, maintains nominal α whi...A maximum test in lieu of forcing a choice between the two dependent samples t-test and Wilcoxon signed-ranks test is proposed. The maximum test, which requires a new table of critical values, maintains nominal α while guaranteeing the maximum power of the two constituent tests. Critical values, obtained via Monte Carlo methods, are uniformly smaller than the Bonferroni-Dunn adjustment, giving it power superiority when testing for treatment alternatives of shift in location parameter when data are sampled from non-normal distributions.展开更多
水力压裂技术是实现低渗油气及地热储层的高效开发利用的关键技术手段,为了研究干热岩型地热储层水力压裂过程中水力裂缝的扩展规律,本文使用粘结单元法(Cohesive Zone Method,CZM)研究了压裂液排量、压裂液粘度以及水平地应力差对水力...水力压裂技术是实现低渗油气及地热储层的高效开发利用的关键技术手段,为了研究干热岩型地热储层水力压裂过程中水力裂缝的扩展规律,本文使用粘结单元法(Cohesive Zone Method,CZM)研究了压裂液排量、压裂液粘度以及水平地应力差对水力裂缝形态的影响,并利用正交试验对上述压裂工艺参数的组合进行优化。结果表明:压裂液排量对水力裂缝的长度具有重要影响,而压裂液的粘度对水力裂缝的宽度具有显著影响;压裂液的排量和粘度的增加,促进了分支裂缝的萌生和扩展;水平地应力差为1 MPa时,本文所建立的模型在压裂液排量和粘度分别取0.004 m3/s和0.07 Pa·s条件下,可获得最佳的压裂改造效果;随着压裂液的排量和粘度的持续增加,当压裂液的排量和粘度分别超过0.004 m3/s和0.07 Pa·s后,继续增加压裂液的排量和粘度将导致水力裂缝的长度和宽度的减小,可见在实际压裂过程中不能盲目通过提高压裂液的排量和粘度的方式实现对压裂效果的持续改进。本文丰富了干热岩储层改造的数值模拟手段,相关研究成果有望为干热岩型地热资源开采过程中裂缝扩展行为预测和压裂工艺参数的优化提供技术支撑。展开更多
基金financially supported by the National Basic Research Program of China (Grant No. 2009CB421 401)
文摘The authors use numerical model integral products in a third level forecast of synthetically multi-level analog forecast technology.This is one of the strongest points of this study,which also includes the re-ducing mean vacant-forecast rate method,which pos-sesses many advantages with regard to filtering the analog term.Moreover,the similitude degree between samples is assessed using a combination of meteorological elements,which works better than that described using a single element in earlier analog forecast studies.Based on these techniques,the authors apply the model output,air sounding,surface observation and weather map data from 1990 to 2002 to perform an analog experiment of the quasi-stationary front rainstorm.The most important re-sults are as follows:(1) The forecast successful index is 0.36,and was improved after the forecast model was re-vised.(2) The forecast precise rate (0.59) and the lost-forecast rate (0.33) are also better than those of other methods.(3) Based on the model output data,the syn-thetically multilevel analog forecast technology can pro-duce more accurate forecasts of a quasi-stationary front rainstorm.(4) Optimal analog elements reveal that trig-gering mechanisms are located in the lower troposphere while upper level systems are more important in main-taining the phase of the rainstorm.These variables should be first taken into account in operational forecasts of the quasi-stationary front rainstorm.(5) In addition,experi-ments reveal that the position of the key zone is mainly decided by the position of the system causing the heavy rainfall.
基金Supported by the National Natural Science Fundation of China(No.31270674)
文摘Low-tempemture stress is a major abiotic stress influencing plant growth, economic yield and quality worldwide. Precise and reliable identification and test of plant cold resistance is a foundation for exploring low-temperature damages, cold resistance mechanism of plants, cultivating and innovating quality cold-re- sistant germplasm resources, which is rather important for woody plants because their perennial and large-sized characteristics. Generally, most researches on plant cold-resistant physiology focused on identification and utilization of cold resistance worldwide, and a few on test methods of cold resistance, but cold resistance mechanism has been less reported. Therefore, researches on methods of identifying and testing plant resistance have achieved considerable progress, accumulated much experience and formed characteristics gradually in terms of methodology. Current methods of identifying plant cold resistance include open field/outdoor culti- vation evaluation, cold and frost damage investigation, simulated cold weather, and mathematical model forecast. And the methods of testing plant cold resistance include growth condition test, frozen index investigation, electrolyte leakage, bioelectrical impedance mapping and so on. Synthesizing the methods of identifying and testing plant cold resistance should be a key matter in the present and future researches and application of plant cold resistance physiology, improvement and in- novation of the identification and test will be an important direction of the future researches. Identification and test of plant cold resistance based on genomies, meta- bonomics and proteomics should be the new trend of the researches on physiology and ecology of plant cold resistance.
文摘Under the current situation of the cosmetics industry,this paper compares the different technical fields of cosmetics at home and abroad and the development status of cosmetic raw materials,discusses the reasons why foreign cosmetic raw materials still occupy the majority of the country,and summarizes the development status of the number of patent applications,cosmetic safety and efficacy evaluation methods,animal substitution and in vitro evaluation technology for cosmetics,the combination of digital beauty and cosmetics and localization of testing equipment,and suggestions on the development of China’s future cosmetic original technology capabilities.
文摘A maximum test in lieu of forcing a choice between the two dependent samples t-test and Wilcoxon signed-ranks test is proposed. The maximum test, which requires a new table of critical values, maintains nominal α while guaranteeing the maximum power of the two constituent tests. Critical values, obtained via Monte Carlo methods, are uniformly smaller than the Bonferroni-Dunn adjustment, giving it power superiority when testing for treatment alternatives of shift in location parameter when data are sampled from non-normal distributions.