小麦保险费率厘定:基于小波分析与非参数估计法

合理厘定保险费率是农作物保险开展的重要前提,可为政府保费补贴等支农政策提供决策依据.本文以北京市冬小麦为样本,采用小波分析和非参数估计方法相结合的方法,改进了农作物保险纯费率厘定方法,提高了计算结果的合理性与准确性,即,利用小波分析法确定作物单产的趋势产量,并在非参数高斯函数为核密度函数设定,借助Silverman的"经验法则”确定带宽,确定了样本数据的概率分布模型,最终完成了北京市冬小麦保险纯费率厘定过程.     

中国乘用车物质代谢与碳减排策略

中国是全球最大的汽车制造和消费国,汽车行业带来的资源消耗和温室气体排放受到了学者的广泛关注.辨析汽车行业的物质资源代谢特征和碳减排潜力可为落实循环经济政策和实现可持续发展提供科学依据.本文基于动态物质流模型,预测了中国乘用车中21种物质材料的代谢特征,评估了乘用车使用过程中的碳减排潜力.研究结果表明:①1949-201...     

Red blood cell recognition and posture estimation in microfluidic chip based on lensless imaging

On the one hand, lensless imaging technology has become one of the key technologies to achieve point-of-care testing; on the other hand, microfluidic technology has shown great application potential in the field of biological detection. Using mainstream lensless imaging technology to achieve biological cell imaging in microfluidic chips has technical limitations. In particular, it is more difficult to achieve lensless imaging for non-spherical cells in microfluidic chips such as red blood cells. Achieving red blood cell recognition and posture estimation in a microfluidic chip under the lensless imaging, combined with mainstream lensless imaging technology, can provide more effective red blood cell morphological parameters for medical diagnosis. In this paper, the method for red blood cell recognition and posture estimation in microfluidic chips based on lensless imaging is given. First, the relevant theoretical basis is introduced. Then, the models of red blood cell recognition and posture estimation in microfluidic chips based on lensless imaging are given. The effect of red blood cell flipping on lensless imaging is analyzed in the modeling process. Finally, the effectiveness of the proposed method is verified by experiments. Experiments show that the proposed method can well achieve red blood cell recognition and posture estimation through the shape characteristics of red blood cells.     

基于BP神经网络的纤维混凝土力学性能预测模型

基于BP神经网络预测模型对不同材料掺量的纤维混凝土进行混凝土力学性能预测,找到适宜的隐藏层单元数和误差目标值.通过将预测数据和实测数据进行对比,研究该预测模型对于混杂纤维混凝土强度预测的可行性.经检验当隐藏层单元数为9个,目标误差值为1e-7时,预测值的准确性最高.     

中职校幼师专业合唱课的训练方法的探索

针对中职校幼师专业学生音乐基础参差不齐的现象,为提高学生的二部歌曲合唱水平,本文总结出一套行之有效的训练方法,即把握音准、节奏,选择适当的作品,注重情感演绎和合唱意识的培养。     

“自学引导型”课堂教学模式的实践探究

本文从改革信息技术课堂教学的现状出发,提出了开展＂自学引导型＂课堂教学模式的愿望。在简要说明＂自学引导型＂教学模式的基本涵义后,针对信息技术课的具体课堂教学过程进行教学实践。运用小组合作式的＂自学引导型＂课堂教学模式,在课堂教学中充分调动学生自主学习、探究性学习的思维方式,突出了信息技术教育在新一轮课程改革中学生的主体地位和作用。     

动态外部环境下的集群企业知识网络演化研究

本文立足于对集群企业知识网络中网络关系演化机理的分析,阐述了动态外部环境在网络关系层面的影响。在此基础上,文章通过对企业知识网络所处集群情境中规模与异质性的分析,构建了动态外部环境影响整体网络演化方式的四维度分析模型,并通过实证研究详细描述了南京大明路汽车销售与服务产业集群中企业知识网络受动态外部环境影响的演化历程。     

高校青年教师职业生涯设计和培养的路径研究

建设高水平的大学,必须加强青年教师职业生涯的设计和培养。针对青年教师的特点,结合学校发展战略和青年教师培养的实际情况,找准目标定位,分析存在问题,提出相应对策,对建立健全高校青年教师职业生涯设计和培养体系,强化教学和科研能力,制定科学、合理的培养机制,具有现实意义。     

日本“福岛核事故”灾后救援现场亲历与思考

中科院代表团应邀于2015年3月25日实地考察了日本"福岛核事故"的灾后救援现场。文章详细介绍了代表团在现场的所见所闻,重点介绍了反应堆厂房应急处理、反应堆冷却水处理、地下水隔离等核事故应急措施及其工程实施进展,同时结合我国核电发展情况,建议我国在全面总结和吸取福岛核事故的经验教训,学习日本的核事故应急处理处置技术和程序,积极加强与日本在核与辐射安全领域的科技合作。     

Guazia,the earliest ovule without cupule but with unique integumentary lobes

The earliest ovules in the Late Devonian (Famennian) are surrounded by a cupule that is involved in both protection and pollination, and generally have free integumentary lobes. Here we report a new taxon from the Famennian of China, Guazia dongzhiensis gen. et sp. nov. The terminally borne ovule is apparently acupulate (without cupule) and has four radially arranged wing-like integumentary lobes that are extensively fused, and folded lengthwise and inwards. Guazia provides evidence that not all Devonian seeds possess a cupule and it increases their diversity in integumentary lobes. This genus also suggests that the integuments develop new functions, probably including wind dispersal at the expense of the cupules.