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美日企业两种组织形态效率比较 被引量:1
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作者 张振华 《当代经济研究》 CSSCI 北大核心 2004年第4期43-45,共3页
虽然人们在组织形态的类型方面,又发展出许多变种混合形式,但是在大型工业企业的管理上主要有两种基本的组织结构,即集中的职能结构类型和分权的事业部制结构。本文通过对企业组织形态的成因分析和美日企业两种组织形态的效率比较,提出... 虽然人们在组织形态的类型方面,又发展出许多变种混合形式,但是在大型工业企业的管理上主要有两种基本的组织结构,即集中的职能结构类型和分权的事业部制结构。本文通过对企业组织形态的成因分析和美日企业两种组织形态的效率比较,提出了成功的企业都力图在集权和分权之间保持平衡的观点。这对我国企业组织形态的建立和创新有重要的借鉴意义。 展开更多
关键词 美国 日本 企业管理 组织形态效率 事业部结构 职能结构
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基于四叉树算法的“三区空间”形态效率评价方法 被引量:2
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作者 夏俊楠 魏伟 +2 位作者 尹力 洪梦谣 薄立明 《地球信息科学学报》 CSCD 北大核心 2023年第3期450-467,共18页
面向多尺度、全要素、长时序“三区空间”形态效率格局解析及其演化机制分析,构建基于“四叉树”算法的“三区空间”识别方法,以“形态效率值”作为空间形态效率的核心衡量手段,构建统一、可比较的“三区空间”形态效率衡量渠道;运用Du... 面向多尺度、全要素、长时序“三区空间”形态效率格局解析及其演化机制分析,构建基于“四叉树”算法的“三区空间”识别方法,以“形态效率值”作为空间形态效率的核心衡量手段,构建统一、可比较的“三区空间”形态效率衡量渠道;运用Dugam基尼系数和空间计量回归分析方法,验证基于“四叉树”算法对国土空间形态描述的有效性,并挖掘形态效率及其变化的影响机制,为宏、中、微观各尺度国土空间的形态监测提供数据适应性强、判别精度高的基础支撑方法。以长江经济带为实证对象,对该典型区域“三区空间”形态效率的特征、变化差异及演化机制进行分析,研究发现:(1)近40年来,城镇空间成片开发水平快速提升,形态效率提升0.46,而农业空间集中连片水平剧烈下降0.17,生态空间基本不变;(2)长江经济带“三区空间”开发保护存在中西部后发地区城镇空间无序开发、全域农业空间形态破碎以及东部地区大规模侵蚀生态空间完整性的风险;(3)关注资源环境承载能力脆弱、社会经济处于高速发展阶段、区位条件相对较差地区的“三区空间”形态效率变化,并制定空间结构与形态优化的相关政策,是优化长江经济带三区空间形态效率的关键。 展开更多
关键词 四叉树 长江经济带 三区空间 土地利用 形态效率 国土空间形态 国土空间规划 国土空间监测
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Genotypic Variation in Root Morphological Characteristics of Common Bean in Relation to Phosphorus Efficiency 被引量:10
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作者 廖红 严小龙 《Acta Botanica Sinica》 CSCD 2001年第11期1161-1166,共6页
Root morphology in plants may be related to phosphorus (P) efficiency by affecting the absorption characteristics of the root system. However, genotypic variation in root morphological characteristics of common bean (... Root morphology in plants may be related to phosphorus (P) efficiency by affecting the absorption characteristics of the root system. However, genotypic variation in root morphological characteristics of common bean ( Phaseolus vulgaris L.) as affected by P availability has not been well clarified. In the present study, systematic studies were conducted in a P-buffered sand culture system using three pairs of common bean parental materials with contrasting root traits in response to P deficiency. The results indicate that P availability significantly affects bean root morphology. Common bean tends to have smaller root system, shorter and coarser roots at low P availability. Genotypic variation in root morphology was observed among different genotypes in response to P availability. The P efficient genotypes appear to have larger, finer and longer root systems than the P inefficient genotypes, and such a variation was particularly obvious in the basal roots. From allomeric analysis, we found that morphological characteristics of the basal roots contribute more to P efficiency than those of the tap roots. Further studies with the F-9 recombinant inbred lines derived from one of the most contrasting parental pairs, DOR364 and G19833, confirmed the above findings, indicating that those morphological characteristics are inheritable hence provide potential for genetic improvement. 展开更多
关键词 common bean root morphology phosphorus efficiency genotypic variation
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Inchworm locomotion gait for snakelike robot 被引量:1
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作者 孙洪 马培荪 王光荣 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期556-560,共5页
To establish a universal and easily controlled gait for practical use of snakelike robot movement, an inchworm locomotion gait model based on a serpenoid curve is presented. By analyzing the relations of two adjacent ... To establish a universal and easily controlled gait for practical use of snakelike robot movement, an inchworm locomotion gait model based on a serpenoid curve is presented. By analyzing the relations of two adjacent waves in the process of locomotion and doing an approximation of the serpenoid curve, the motion function of relative angles between two adjacent links and the absolute angles between each link and the baseline on the traveling curve are built. Two efficiency criterions of the gait are given as the energy loss function f and the unit displacement in one cycle dunit.Three parameters of the criterions affecting the efficiency of the gait ( the number of links that form the traveling wave n, the included angle between two adjacent links α, and the phase difference of adjacent included angles β) are discussed by simulations and experiments. The results show that f is insensitive to n; raising n increases dunit significantly; the maximum wave amplitude of α is a decreasing function of n; and increasing α reduces the displacement influence off when n is determined. The gait model is suitable for different inchworm locomotions of a snakelike robot whose traveling waves are formed by different numbers of identical links. A wave formed by more links or a greater relative angle between two adjacent links both lead to greater velocity of the movement. 展开更多
关键词 snakelike robot multilink inchworm locomotion gait efficiency criterion
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Effects of Silicon at Different Concentrations on Morphology and Photosynthetic Physiological Mechanism of Japonica Rice 被引量:1
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作者 陈亮 蔡丽萍 +2 位作者 周彬 石妍 饶梦 《Agricultural Science & Technology》 CAS 2012年第9期1877-1880,1907,共5页
[Objective] The aim was to explore effects of silicon at different concentrations on morphology and photosynthetic physiological mechanism of japonica rice. [Method] Seedlings of japonica rice were treated with silico... [Objective] The aim was to explore effects of silicon at different concentrations on morphology and photosynthetic physiological mechanism of japonica rice. [Method] Seedlings of japonica rice were treated with silicon at different concentrations (0, 30, 80, 130 and 180 mg/L of sodium silicate); silicon contents were measured with Molybdenum blue spectrophotometric method in root, stem and leaf; plant height, root length and number in different treatment groups were measured with tools; chlorophyll a and b, and a/b in leaf and stem of rice in different groups were measured. [Result] Silicon contents in vegetative organs were as follows: stem〉leaf〉 root; when silicon was 80 mg/L, japonica ecotype was shortest; when silicon was 30 mg/L, root length of the rice was shortest and root number was least; when silicon was 30 mg/L, contents of chlorophyll a and b were highest and chlorophyll a/b achieved the peak when silicon was 80 mg/L. [Conclusion] Silicon at proper concen- tration would improve lodging-resistance and efficiency of photosynthesis, further enhancing yield of japonica rice. 展开更多
关键词 Japonica ecotype Silicon concentration Morphological characteristics Photosynthetic efficiency
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知识经济如“何” 知识如何“经济” 如何知识经济?
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作者 许计海 秦宝文 《河北企业》 2000年第10期32-33,共2页
知识经济的出现只是本世纪末的事,我们对它的认识还应该说仅仅是开始,故近年来围绕知识经济问题确不乏仁智之见。本文也想就此问题谈几点看法,以共商榷。(一)知识经济如"何"?这应当是认识事物的第一思维层次。不论从理论上讲... 知识经济的出现只是本世纪末的事,我们对它的认识还应该说仅仅是开始,故近年来围绕知识经济问题确不乏仁智之见。本文也想就此问题谈几点看法,以共商榷。(一)知识经济如"何"?这应当是认识事物的第一思维层次。不论从理论上讲,还是从实践上讲,知识经济都应该说是远比农业经济、工业经济更为复杂的社会经济现象。从历史唯物主义的观点讲,知识经济是社会生产力发展的必然产物。严格地说,经济作为人类独有的社会范畴,从产生之日起就是靠知识支撑的,就是以知识的转化形态存在着的,人类从刀耕火种的生存方式中(此时还没有出现经济) 展开更多
关键词 知识经济 功能形态 效率形态 技术落差 人才
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如何面对知识经济?
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作者 许计海 秦宝文 《科技与企业》 2000年第12期25-26,共2页
关键词 知识经济 动能形态 效率形态 文化形态 产业形态
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模块化机器人的模块形态特性 被引量:1
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作者 刘策越 刘建功 +1 位作者 刘扬 Andres Faina 《吉林大学学报(工学版)》 EI CAS CSCD 北大核心 2019年第1期199-208,共10页
针对目前尚无一种通用的方法对模块形态与模块化机器人的性能关系进行分析研究,以EMERGE模块形态为目标对象,基于进化设计的思想,提出一种模块形态的评估方法。首先,依据模块可用的连接面数量及其相对位置对模块形态进行分类分析。然后... 针对目前尚无一种通用的方法对模块形态与模块化机器人的性能关系进行分析研究,以EMERGE模块形态为目标对象,基于进化设计的思想,提出一种模块形态的评估方法。首先,依据模块可用的连接面数量及其相对位置对模块形态进行分类分析。然后采用结构化的进化设计策略,以平面的移动任务为算例,在机器人仿真平台中分别对由不同种类形态的模块组建的机器人进化,得到每种模块形态下性能最优的机器人,并比较各自的性能。最后,对不同种类的最优性能的仿真机器人进行实体机器人验证。结果表明该评估方法可有效提高设计高性能模块化机器人的效率,仿真和实体机器人试验验证了方法的有效性。 展开更多
关键词 自动控制技术 模块化机器人 模块形态 形态和控制的进化 统计分析 形态效率
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Effects of spin-coating speed on the morphology and photovoltaic performance of the diketopyrrolopyrrole-based terpolymer 被引量:1
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作者 Fen Wu Rongyan Hou +2 位作者 Liang Yang Bin Zhao Songting Tan 《Science China Chemistry》 SCIE EI CAS CSCD 2016年第4期466-471,共6页
Polymer solar cells(PSCs) were fabricated by combining a diketopyrrolopyrrole-based terpolymer(PTBT-HTID-DPP) as the electron donor, and [6,6]-phenyl C_(61) butyric acid methyl ester(PC_(61)BM) as the electron accepto... Polymer solar cells(PSCs) were fabricated by combining a diketopyrrolopyrrole-based terpolymer(PTBT-HTID-DPP) as the electron donor, and [6,6]-phenyl C_(61) butyric acid methyl ester(PC_(61)BM) as the electron acceptor, and the power conversion efficiency(PCE) of 4.31% has been achieved under AM 1.5 G(100 m W cm^(-2)) illumination condition via optimizing the polymer/PC_(61)BM ratio, the variety of solvent and the spin-coating speed. The impact of the spin-coating speed on the photovoltaic performance of the PSCs has been investigated by revealing the effects of the spin-coating speed on the morphology and the absorption spectra of the polymer/PC_(61)BM blend films. When the thickness of the blend films are adjusted by spin-coating a fixed concentration with different spin-coating speeds, the blend film prepared at a lower spin-coating speed shows a stronger absorption per unit thickness, and the correspond device shows higher IPCE value in the longer-wavelength region. Under the conditions of similar thickness, the blend film prepared at a lower spin-coating speed forms a more uniform microphase separation and smaller domain size which leads to a higher absorption intensity per unit thickness of the blend film in long wavenumber band, a larger short-circuit current density(J_(sc)) and a higher power conversion efficiency(PCE) of the PSC device. Noteworthily, it was found that spin-coating speed is not only a way to control the thickness of active layer but also an influencing factor on morphology and photovoltaic performance for the diketopyrrolopyrrole-based terpolymer. 展开更多
关键词 polymer solar cells device optimization spin-coating speed MORPHOLOGY absorption per unit thickness
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