The paper presents the research for the purpose of selecting microorganisms into the production process of "chao" to improve the quality of "chao" products and ensure food safety. Several analytical methods such a...The paper presents the research for the purpose of selecting microorganisms into the production process of "chao" to improve the quality of "chao" products and ensure food safety. Several analytical methods such as determination of formal nitrogen, determination of the protease hydrolysis activity, sensory evaluation method, experimental procedure, methods of analysis and processing of empirical data were used in this study. The findings showed that two out of four selected microorganism strains (one strain of fungi and three strains of bacteria denoted NM1, VK1, VK2, VK3, respectively) were the most appropriate for the cooperation among them and the production of %hao", which were coded NM1 and VK1. The suitable mixing proportion of strains of NM1 and VK1 was determined at 1:1.25, compatible with the 1:100 ratio of the varieties of microorganisms (in powder form) to tofu.展开更多
大规模开发和利用风能有利于实现电力系统清洁低碳转型,是实现国家“碳达峰、碳中和”战略目标的重要技术手段,但风电出力的强不确定性对电力系统区域间可用输电能力(available transfer capability,ATC)评估带来了全新的挑战,传统用于...大规模开发和利用风能有利于实现电力系统清洁低碳转型,是实现国家“碳达峰、碳中和”战略目标的重要技术手段,但风电出力的强不确定性对电力系统区域间可用输电能力(available transfer capability,ATC)评估带来了全新的挑战,传统用于求解计及风电出力不确定性的概率ATC评估模型在计算效率和计算精度方面均存在一定的不足。为此,该文提出一种基于多项式混沌展开(polynomialchaos expansion,PCE)的电力系统概率ATC评估方法,该方法首先构建基于机会约束的电力系统概率ATC评估模型;然后,根据风电出力预测误差的概率分布特征,选择对应的正交多项式为基函数以近似风电出力预测误差及电力网络中与之相关联的其他随机变量;进一步,借助Galerkin投影和基于一阶矩、二阶矩的机会约束转化方法,将所构建的机会约束模型的概率约束转化为确定性约束,实现基于机会约束的概率ATC评估模型向易于求解的确定性优化模型的转化;进而,将概率ATC评估模型的求解问题转化为ATC的最优多项式逼近系数的求解问题,根据求得的最优多项式逼近系数和选取的基函数计算电力系统ATC的概率分布特征;最后,通过修改后的PJM-5节点测试系统、IEEE-118节点测试系统及吉林西部电网实际算例验证了所提基于多项式混沌展开的电力系统概率ATC评估方法的准确性和有效性。展开更多
文摘The paper presents the research for the purpose of selecting microorganisms into the production process of "chao" to improve the quality of "chao" products and ensure food safety. Several analytical methods such as determination of formal nitrogen, determination of the protease hydrolysis activity, sensory evaluation method, experimental procedure, methods of analysis and processing of empirical data were used in this study. The findings showed that two out of four selected microorganism strains (one strain of fungi and three strains of bacteria denoted NM1, VK1, VK2, VK3, respectively) were the most appropriate for the cooperation among them and the production of %hao", which were coded NM1 and VK1. The suitable mixing proportion of strains of NM1 and VK1 was determined at 1:1.25, compatible with the 1:100 ratio of the varieties of microorganisms (in powder form) to tofu.
基金funded by NERC grant NE/M012190/1, China Scholarship Council (No. 201708320317)National Natural Science Foundation of China (Grant No. 41974073, Grant No. 41404053, Grant No. 41604134, Grant No. 41174165, Grant No. 41974073)+3 种基金Special Project for Meteo-scientific Research in the Public Interest (Grant No. GYHY201306073-2)Macao Foundation and the pre-research project on Civil Aerospace Technologies No. D020308 and D020303 funded by China’s National Space Administrationopening fund of State Key Laboratory of Lunar and Planetary Sciences (Macao University of Science and Technology) (Macao FDCT grant No. 119/2017/A3)the Specialized Research Fund for State Key Laboratory of Space Weather, Graduate Research and Practice Innovation Program (KYCX17_0896),the Specialized Research Fund for State Key Laboratory of Space Weather
文摘大规模开发和利用风能有利于实现电力系统清洁低碳转型,是实现国家“碳达峰、碳中和”战略目标的重要技术手段,但风电出力的强不确定性对电力系统区域间可用输电能力(available transfer capability,ATC)评估带来了全新的挑战,传统用于求解计及风电出力不确定性的概率ATC评估模型在计算效率和计算精度方面均存在一定的不足。为此,该文提出一种基于多项式混沌展开(polynomialchaos expansion,PCE)的电力系统概率ATC评估方法,该方法首先构建基于机会约束的电力系统概率ATC评估模型;然后,根据风电出力预测误差的概率分布特征,选择对应的正交多项式为基函数以近似风电出力预测误差及电力网络中与之相关联的其他随机变量;进一步,借助Galerkin投影和基于一阶矩、二阶矩的机会约束转化方法,将所构建的机会约束模型的概率约束转化为确定性约束,实现基于机会约束的概率ATC评估模型向易于求解的确定性优化模型的转化;进而,将概率ATC评估模型的求解问题转化为ATC的最优多项式逼近系数的求解问题,根据求得的最优多项式逼近系数和选取的基函数计算电力系统ATC的概率分布特征;最后,通过修改后的PJM-5节点测试系统、IEEE-118节点测试系统及吉林西部电网实际算例验证了所提基于多项式混沌展开的电力系统概率ATC评估方法的准确性和有效性。