Results 61 to 70 of about 13,453 (210)
Analysis of tax increase in the perspective of industry transformation——Base the data of Wuxi [PDF]
, 2015 改革开放以来，中国经济保持了30多年的资本拉动型高速增长，只是到近年才开始进入中速增长,从横向的世界范围内对比，我国的经济增速仍然处于高位运行。一直以来我国税收增长处于一种超GDP增长的态势，这种态势随着2008年经济危机发生出现了拐点，税收增长速度开始下降，可以说我国的税收增长也进入了一种“新常态”，经济总量导引的税收增长模式难以为继。目前我国经济正在从总量增长模式逐步向产业结构性调整模式转变，我国产业转型正在发生内涵性的改变，从原来注重三大产业结构比重的水平性变化向更具创新力、竞争性的层次性变革 ...
查琴琴
core
MXene‐Based Electromagnetic Attenuation Materials in Microwave and Terahertz Bands
Rare Metals, EarlyView.ABSTRACT MXenes exhibit considerable potential for developing high‐performance electromagnetic (EM) shielding and absorption materials operating across microwave and terahertz frequencies, due to their tunable surface chemistry and exceptional charge carrier transport properties.
Guozheng Zhang +9 more
wiley +1 more source
The Impact of Venture Capital on the IPO Process of Private Enterprises in China [PDF]
, 2016 当前我国经济步入“新常态”，经济结构优化升级，体现出创新驱动发展的新特点。在此背景下，民营企业数量剧增，成为“新常态”的主力军，对国民经济的贡献越来越多；同时资本和技术要素地位越来越重要，关注风险投资对民营企业的影响具有较高的研究价值。本文选题风险投资对我国民营企业首发上市的影响，集中关注风险投资给民营企业首发上市价格方面（发行价格、首日收盘价格）所带来的作用。风险投资是现代金融学研究的热点，关于其对被投资企业所起的作用国外有正面的认证监督功效假说和反面的逆向选择理论、市场力量假说 ...
黄小娟
core
Rare Metals, EarlyView.ABSTRACT Organic‐inorganic metal halide perovskite solar cells (PSCs) are promising for photovoltaics due to their excellent optoelectronic properties. However, achieving high efficiency and stability remains challenging, mainly due to defects and energy losses at the electron transport layer (ETL)/perovskite interface.
Jiahui Jin +8 more
wiley +1 more source
A High Capacity‐Long Cycling Concurrent Strategy of Ti3C2/MgH2 for Lithium Storage
Rare Metals, EarlyView.ABSTRACT The excellent electrical conductivity and superior cycling stability render Ti3C2 MXene a promising Li ion battery anode. Nevertheless, the practical implementation of Ti3C2 MXene in commercial applications faces significant challenges, predominantly due to the low specific capacity.
Tingting Xu +9 more
wiley +1 more source
Jianzhu Gangjiegou Jinzhan, 2010 针对5种典型单层球面网壳结构型式（联方型、施威德勒型、凯威特型、三向格子型和短程线型）,本文采用基于离散变量的序列两级截面优化算法对一百个不同跨度（30m60m）、不同矢高（1/31/7）的网壳进行截面优化设计,在截面优化设计结果中提取选型所需的优秀样本,一个优秀样本由3部分组成:跨度,矢跨比和该跨度、矢跨比下用钢量最少的网壳结构类型;然后利用BP人工神经网络对复杂非线性映射关系的模拟能力建立网壳跨度、矢跨比与用钢量最少的网壳型式之间的映射关系,避免了结构选型优化的多维、多重非线性模型的求解困难 ...
陈世英, 郭玉霞, 鹿晓阳
doaj
probability neural network based on particle swarm optimization algorithm [PDF]
, 2016 标签分布学习是近几年发展起来的解决多标签分类问题的方法。该方法基于这样的假设：属于不同标签的实例可能会存在部分的共同特征，因此在学习过程中，每个实例都可以对不同的标签做出贡献，这极大地降低了学习的难度。条件概率神经网络作为解决这个模型的算法，在进行分类时具有独特的优势，然而如何对其进行有效的训练，从而找到最优参数却是一个困难的问题。 本文对条件概率神经网络的优化进行了研究，在考虑标签分布的性质和条件概率神经网络的结构特点之后，从三个方面改进了条件概率神经网络，并将改进的条件概率神经网络应用于年龄估计问题，
徐骏捷
core
Rare Metals, EarlyView.ABSTRACT Transition metal‐based amorphous/crystalline (a/c) heterostructured catalysts have garnered significant attention due to their exceptional activity, stability, and cost‐effectiveness. However, the precise synergistic regulation of interfacial composition and phase states remains challenging.
Haoran Li +3 more
wiley +1 more source
Dianci bileiqi, 2013 圆柱头盘形悬式瓷绝缘子（简称圆柱头产品）,结构规整,加工量小,生产效率高,但大吨位产品头部结构过大。笔者从轻量、节约、稳定的角度出发,用有限元法对圆柱头产品进行结构优化,采用ANSYS软件,设计三层台阶的钢脚结构,最终优化出高性能与稳定性的头部结构。
高军
doaj
Rare Metals, EarlyView.ABSTRACT Organic‐inorganic hybrid perovskites (OIHPs) with white‐light emission have significant potential in solid‐state lighting and display due to the designable structure and excellent luminescent properties. However, OIHPs are prone to damage during bending due to the brittleness of crystals, which limits their application in the field of flexible
Jinyu Xu +8 more
wiley +1 more source