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511.
一种新型三角形组合振子超宽带天线   总被引:1,自引:1,他引:0  
以三角形振子天线为基础对天线结构进行改进,提出了一种新型三角形组合振子天线.仿真研究表明该天线与普通三角形振子天线相比,具有更好的宽频带特性,而且尺寸更小.对三角形组合振子天线的输入阻抗特性进行了分析,仿真结果表明该天线在0.13~2GHz频带范围内,具有稳定的阻抗带宽,说明所设计的天线具有超宽带特性.  相似文献   
512.
This meta‐analysis investigates the direction and strength of the relationship between diversity in culturally diverse teams and team creativity/innovation. We distinguish the effects of two diversity levels (i.e., surface level vs. deep level) in culturally diverse teams and examine the moderators suggested by the socio‐technical systems framework (i.e., team virtuality and task characteristics in terms of task interdependence, complexity, and intellectiveness). Surface‐level diversity in culturally diverse teams is not related to team creativity/innovation, whereas deep‐level diversity in culturally diverse teams is positively related to team creativity/innovation. Moreover, surface‐level diversity in culturally diverse teams and team creativity/innovation are negatively related for simple tasks but unrelated for complex tasks. Deep‐level diversity in culturally diverse teams and team creativity/innovation is positively related for collocated teams and interdependent tasks but unrelated for noncollocated teams and independent tasks. We discuss the theoretical and practical implications.  相似文献   
513.
This multistudy research examines the unit‐level relationship between promotive voice behavior and management innovation. Study 1 utilizes multisource data from 62 work units and reports that willingness to discuss ideas mediates the unit‐level relationship between promotive voice and management innovation. The results of Study 1 also show that the unit's available resources make the relationship stronger between promotive voice and willingness to discuss ideas. Study 2 employs a scenario‐based design to constructively replicate and expand the results of Study 1, utilizing a sample of 100 working adults. The results of the second study also show that resource availability positively moderates the relationship between promotive voice and willingness to discuss ideas. Furthermore, Study 2 shows that the indirect effect of promotive voice on management innovation through willingness to discuss ideas is stronger when more resources are made available to the work units. This moderated‐mediation effect is shown to be significant using two different operationalizations of management innovation. The implications for theory and practice are discussed.  相似文献   
514.
建筑施工企业在安全资金的投入和使用上都存在不合理的现象,为提高企业的安全管理水平,确保安全投入高效性,有必要对建筑施工企业的安全投入结构进行优化.通过调查问卷的形式调研65个建筑施工项目的安全管理人员,筛选出主要安全投入要素.然后运用解释结构模型(ISM)结合层次分析法(AHP)构建安全投入结构优化模型.并且,根据调查...  相似文献   
515.
运用"流变-突变"理论分析煤矿安全投入的效果,发现其随着时间的推移也表现出"安全流变-突变"的特征。笔者指出,安全投入应该是持续的、不断进行的,不能靠期初一次性安全投入解决,而且后续安全投入应该选择在最佳时段(即不安全度加速发展阶段)进行,最晚不能超过安全突变的预警点,这样才能使系统的安全流变阶段能够尽量延长,从而最大限度地发挥所有安全投入的效果,缓解我国煤矿安全投入需求增长与安全投入不足的矛盾。  相似文献   
516.
知识网络是由创造、转移、吸收和应用知识的行为主体在知识的传播与交流过程中彼此联结而形成的网络结构。以国际ISI和国内VIP数据库中2000~2009年发表于生物技术领域的合著论文作者信息统计数据为数据源,基于社会网络分析的理论和方法,从国际和国内省级层面运用UCINET和Pajek软件分析知识网络的空间极化和扩散规律。总体上看网络仍处于量的扩张期,网络的稳健性正在逐步提高,网络结构开始向成熟型转变。国际层面上看,知识网络的空间极化现象明显。国内层面上看,知识网络由等级结构向扁平结构转变,空间上相应地经历了由一极向多核再向多中心发展的过程。依据知识网络空间分布特征,将知识交流区域分为知识集聚区、知识门户区、知识途径区及知识边缘区四大类型,并对我国的技术创新政策提出对策建议  相似文献   
517.
长江经济带城市创新能力差异的时空格局演变   总被引:1,自引:0,他引:1  
以长江经济带130个城市作为空间观测单元,以专利申请量作为衡量各城市创新能力的指标,对长江经济带各城市2000~2014年创新能力的空间分布及演化进行分析。研究表明:(1)从时空总体演变来看,长江经济带城市创新能力表现出非常显著的区域差异,且呈现出由渐进式集聚向缓慢扩散的发展趋势。(2)从空间聚类分布来看,长江经济带创新能力较高的城市主要分布在东部的长三角地区和中西部的省会城市地区。(3)从空间分布演变来看,长江经济带城市创新能力表现出显著的空间自相关,空间分布集聚态势增强,但在地理空间的差异上呈现出缩小的趋势,且不同集聚区在不同空间范围上都表现出一定的扩展与收缩态势。(4)城市的经济发展水平、创新主体、创新投入及创新基础设施的差异性,对长江经济带城市创新能力呈现出不均衡的空间分布产生重要影响。  相似文献   
518.
This paper constructed extended CDM model to study the effects of environmental regulation on industrial innovation and productivity based on the perspective of strong and weak “Porter hypothesis”, by using 28 manufacturing industry panel data of 2003–2014. The findings reveal that: (1) the impact of environmental regulation on R&D intensity lags behind. In the long run, environmental regulation intensity has a significant role in promoting R&D investment in manufacturing industry. (2) The R&D has a significant role in promoting the substantial innovation of manufacturing industry, and has a strong lag and continuity. However, the R&D intensity has no obvious effect on strategic innovation of manufacturing industry. (3) The substantial innovation doesn’t significantly promote the economic performance of manufacturing industry, but it has a significant role in promoting the energy performance of manufacturing industry, and the substantial innovation plays a significant role in promoting environmental performance in the long term. The strategic innovation significantly promotes the economic performance of manufacturing industry, and it inhibits the energy performance and has no significant effect on environmental performance in the short term. It can promote the energy performance of manufacturing industry, but significantly inhibit environmental performance in the long term. (4) Environmental regulation has significantly suppressed the substantive innovation and strategic innovation of manufacturing industry, and the weak Porter hypothesis has not yet been supported. In the short term, environmental regulation inhibits manufacturing economic performance, but it can promote energy and environmental performance. In the long run, environmental regulation promotes the economic and energy performance of manufacturing industry, but it inhibits environmental performance. The establishment of strong Porter hypothesis has a certain scenario.  相似文献   
519.
The Government of Canada has committed that Canada’s total greenhouse gas (GHG) emissions be reduced by 17% from 2005 levels by 2020. The new Renewable Fuels Regulations required 2% renewable content in diesel fuel and heating distillate oil and 5% for gasoline. This represents approximately 2.1 billion liters of ethanol and 600 million liters of biodiesel requirement per year, which would reduce GHG emissions by more than four million tones. Canada is expected to consume more fuel ethanol compared to its production capacity. The above mandates as well as the gap in consumption and production of biofuel will have enormous impact on the Canadian economy. In this backdrop, an input–output model of the Canadian economy is developed to estimate the macroeconomic impact of the ethanol and biodiesel production in Canada. The impacts on sectoral prices have also been calculated. Simulation exercises have been attempted to reach the mandates using modified Leontief model. Results show that agriculture sector is affected because of feedstock use in the biofuel sector. Mining and manufacturing industries also show a considerable impact. In addition, the impact on commodity prices cannot be ignored. Finally, to meet the target of Copenhagen commitment, the nation needs to revise the blending capacity of ethanol and biodiesel.  相似文献   
520.
Abstract

Re-distributed manufacturing (RDM), broadly described as manufacturing done at a smaller-scale and locally, could be beneficial to business and urban society through creating jobs, reducing the environmental impacts of production, and improving resilience to future disturbances. Consideration of RDM within a city-region requires the consideration of a wide range of issues – societal, technical, economic and environmental. This paper presents the results of a study into the potential for RDM to contribute to a sustainable, resilient city in the face of a range of expected future disturbances on the city and on manufacturing sectors. The study took an integrated assessment approach which incorporated the development of a conceptual framework; a ‘strawman’ causal loop diagram which was reviewed by participants in a workshop; and a stock and flow system dynamics model that represents our understanding about the structure and behaviour of urban manufacturing. Several key themes emerged: similarities between RDM and traditional manufacturing, availability of physical space for RDM to be done, achieving urban resilience through RDM by enabling responsiveness to disturbances, changes in environmental impacts from production, additions or losses in jobs, the competitiveness of local manufacturing, and skills and innovation for RDM technologies. Further work is recommended.  相似文献   
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