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941.
942.
知识型企业能力集优化及其组织智商   总被引:1,自引:0,他引:1  
知识型企业是具有动态优化能力集合的有机生命体 .为具备快速应变能力 ,知识型企业在组织结构上应是由智能单元、中央决策智能单元通过适时、适当连接形成的动态网络 .本文基于知识型企业的生存与发展的定义 ,给出知识型企业生命体动态优化的能力集的子集———能力基的概念 ,研究了能力基的动态优化过程 ;本文证明了知识型企业生命体智能单元间联权重的变化率———生命体智商 ,随知识型企业生命体应变能力的提高而提高 ;应变能力的提高 ,通过智能单元间权重的变化而实现  相似文献   
943.
944.
945.
农民工问题与对策   总被引:5,自引:0,他引:5  
农民工作为一弱势群体,其存在是有历史和经济原因的,也与政策和社会环境有关。农民进城打工不仅给自己带来许多好处,也为城市和整个社会的发展作出了巨大的贡献。必须采取一系列措施,使农民工的生存状况和待遇得到改善。  相似文献   
946.
A new site-specific nutrient management approach was developed to break the apparent attainable yield barrier of 6 t·ha−1 in the double rice cropping system of Zhejiang. On-farm experiments involving 21 rice-growing farmer families and NPK long-term experiments commenced in 1997 in the central part of Zhejiang Province to assess the status of soil fertility and productivity under intensive rice-rice cropping. A new site-specific nutrient management (SSNM) approach has been developed for this studied area. Field-specific fertilizer recommendations are calculated considering indigenous nutrient supply, reasonable grain yield targets and corresponding nutrient demand, nutrient balance and nutrient use efficiency, as well as socio-economic factors. The agronomic performance of SSNM was tested against the farmer's fertilizer practice (FFP) in four 1998–1999 cropping seasons. Across seasons and years, SSNM consistently increased plant nutrient uptake, grain yield and profit by about 10%–15% compared to the FFP. Yield levels of 7.5 t·ha−1 or more seem achievable and sustainable through introduction of SSNM and improved extension services in Zhejiang Province. Project supported by the International Fertilizer Industry Association(IFA), the Potash and Phosphate Institute, Canada (PPIC), and International Potash Institute(IPI).  相似文献   
947.
A novel floating foundation to support the NREL offshore 5 MW wind turbine was designed conceptually by combining the characteristics of barge and Spar. The main focus was structural design and hydrodynamic modelling. Based on this novel floating foundation, the hydrodynamic performance was investigated in the frequency domain and time domain by using the wave analysis software HydroD and DeepC from Det Norske Veritas. The frequency domain analysis was conducted to investigate the effects of the incident wave angle and water depth. The time-domain analysis was carried out to evaluate the response of the floating foundation under a selected operational condition. The hydrodynamic performances of this floating foundation with respect to time series and response spectra were also investigated in this study.  相似文献   
948.
1IntroductionIt is i mportant for the economic development of acountry to maintain the stabilization of exchange rate,so the intervention of exchange rate has become thetopic of the main concerns of the economic and math-ematical circles[1-5].To maintain the stabilization ofexchange rate,many countries use target zone re-gi mes,that is,the central banks intervene in the for-eign exchange market such that the exchange ratestays within the interval[a,b].There are fixed costand cost proportional …  相似文献   
949.
Chang  Xin  Zhang  Chengyu  Gao  Lan  Liu  Xiao  You  Shengping  Qi  Wei  Wang  Kang  Guo  Xin  Su  Rongxin  Lu  Han  He  Zhimin 《天津大学学报(英文版)》2019,25(5):488-496
2,5-Furandicarboxylic acid(FDCA) is a potential biorenewable chemical for applications including plastics, polyamides, drugs, etc. The selective biosynthesis of FDCA from 5-hydroxymethylfurfural(HMF) by a specific enzyme poses a great challenge. In this study, we reported an efficient strategy to produce FDCA from HMF by the tandem biocatalysis of laccase(Cot A-TJ102@UIO-66-NH_2) and Novozym 435. For the first step, a nanoparticle metal–organic framework was synthesized as a carrier to immobilize Cot A-TJ102@UIO-66-NH_2, which was assigned for the production of 5-formyl-2-furancarboxylic acid(FFCA) and featured an enzyme loading of 255.54 mg/g, specific activity of 135.90 U/mg, and solid loading ratio of 99.65%. Under optimal conditions, an ideal FFCA yield of 98.5% was achieved, and the Cot A-TJ102@UIO-66-NH_2 presented a high recycling capacity after 10 cycles. For the second step, Novozym 435 was applied for the further conversion of FFCA into FDCA, presenting a high FDCA yield of 95.5% under the optimized conditions. Novozym 435 also exhibited a high recyclability after eight cycles. As a result, the tandem biocatalysis strategy provided a 94.2% FDCA yield from HMF, indicating its excellence as a method for FDCA production.  相似文献   
950.
中国共产党作为我国的执政党,其执政方式的确立及演变有一个历史过程,取决于各方面的因素。在新的历史条件下,也要适应国情和社会环境的变化而不断的改进,从而使党的领导效能趋向优化,更快的把我们国家带入现代化社会。本文就试图从法律角度来研究我党执政方式的演变与改进,更好的推进依法治国方略的贯彻实施。  相似文献   
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