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51.
福州市三次产业结构变化分析 总被引:1,自引:0,他引:1
基于福州市1997-2007年统计数据,采用产业结构偏离度、产业结构变动度、区位熵、偏离-份额分析法,从产业结构效益、产业结构变化及在福建省所处地位、产业结构对经济增长贡献,三个方面衡量福州市产业结构变化情况并分析其对经济增长的影响。 相似文献
52.
汽车博物馆是汽车历史的浓缩,是汽车工业的承载体.通过对国内外典型汽车博物馆建筑实例进行剖析,分析汽车博物馆建筑设计理念,探讨汽车博物馆建筑设计的方法. 相似文献
53.
A time-optimal aircraft-following model is introduced to address air traffic flow interference by velocity reduction. The objective function is set up as minimizing the recovery time during which the separation minima are not infringed and the separation of the air traffic flow returns to the initial separation at the terminal time. Pontryagin’s minimum principle is used to solve the optimum aircraft-following velocity control law. An analytical minimum safe following separation is also provided under the time-optimal control law. The simulation results show that the precision first-order tracking accuracy is achieved without losing the separation.
相似文献54.
能耗的持续增长是当前电信企业面临的重大问题,能耗监测体系和能耗管理系统的不健全,导致电信相关企业对能耗的实际情况不能全面的掌握,以至于节能改造项目的实施也存在诸多问题。根据要求,某通信集团公司将集中建设能耗管理平台,对电能进行集中管理。目前某省通信公司已有的能耗管理平台存在耗电量统计不准确,人性化设计较弱,采集信息显示不完整,无法提供全网能耗分析需求的信息等问题。本系统的改造建设以现有能耗管理平台为基础,通过网管中心虚拟化方式,构建全面的能耗管理平台,对电能实现集中管理,并为之后的节能减排项目提供技术支撑。本文所涉及的实践知识和技术资料可为之后相关领域的能耗管控相关工程提供参考和指导。 相似文献
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The new hybrid elements are proposed by combing modified Hermitian wavelet elements with ANASYS elements. Then hybrid elements are substituted into finite element formulations to solve the load identification. Transfer matrix can be constructed by using the inverse Newmark algorithm and hybrid finite element method. Loads can obtain through the responses and the transfer matrix. Load identification law was studied under different excitation cases in rod and Timoshenko beam. Regularization method is adopted to solve ill-posed inverse problem of load identification. Compared with ANSYS results, hybrid elements and HCSWI elements can accurately identify the applied load. Numerical results show that the algorithm of hybrid elements is effective. The accuracy of hybrid elements and HCSWI elements can be verified by comparing the load identification result of ANASYS elements with the experiment data. Hermitian wavelet finite element methods have high accuracy advantage but it is difficult to apply the engineering practice. In practical engineering, complex structure can be analyzed by using the hybrid finite element methods which can be obtained the high accuracy in the crucial component. 相似文献
57.
In the environment of space radiation, the high-energy charged particles or high-energy photons acting on a spacecraft can cause either temporary device degradation or permanent failure. The traditional probability model is difficult to obtain reliable estimation of unit radiation resistance performance with small samples. Considering that different products will change differently after high-energy particle radiation, we construct a model based on the gamma degradation process. This model can efficiently describe the law of unit radiation resistance variation with the total radiation dose levels under the effect of the total dose and displacement damage. Finally, the proposed model is used to assess the anti-radiation performance of the N-channel power MOSFET device STRH60N20FSY3 produced by STM to obtain average unit radiation resistance, survival probability, survival function, etc. 相似文献
58.
This study aimed to improve the hydraulic potential properties of the slag. Therefore, a method of dynamic hydrothermal synthesis was applied to synthesize calcium silicate hydrate. The phases and nanostructures were characterized by XRD, FTIR, TEM, and BET nitrogen adsorption. The infl uence of alkalinity of steel slag on its structures and properties was discussed. The experimental results show that, the main product is amorphous calcium silicate hydrate gel with fl occulent or fi brous pattern with a BET specifi c surface area up to 77 m2/g and pore volume of 0.34 mL/g. Compared with low alkalinity steel slag, calcium silicate hydrate synthesized from higher alkalinity steel slag is prone to transform to tobermorite structure. 相似文献
59.
研究以鸡肉脂肪为主要原料制备肉味香精的前体物质,通过单因素和正交试验确定氧化反应的最佳反应条件.结果表明氧化鸡肉脂肪的最佳条件是:氧化温度为120℃,氧化时间为3h,VE的添加量为1.0%,不添加水和NaCl.在最优条件下进行氧化试验,得到产物的酸值和过氧化值分别为1.472 mg/g和193.51 mmol/kg,感官评价值为4.905,具有典型特征的鸡肉香气. 相似文献
60.
Hailin Yu Yifan Xia Hanwen Zhang Xinjian Gong Pengfei Geng Zhenwei Gao Yinghan Wang 《应用聚合物科学杂志》2021,138(6):49803
In this work, semiinterpenetrating polymer network (semi-IPN), consisting of sulfonated poly (arylene ether sulfone) (SPAES) and crosslinked vinyl imidazole grafted polysulfone (VMPSU), is prepared and characterized. FTIR, EDS, and solubility test indicate the successful preparation of amphoteric membranes. The semi-IPN amphoteric membranes exhibit better stability than pure SPAES membrane, as demonstrated by thermogravimetric analysis and ex situ immersion testing results. More importantly, it is shown that the amphoteric membrane can effectively hinder vanadium ion crossover through the membrane, which is attributed to the semi-IPN structure and Donnan exclusion. As expected, the amphoteric membrane containing 20% VMPSU exhibits the highest proton selectivity (6.86 × 104 S min cm−3), comparing to pristine SPAES (1.90 × 104 S min cm−3) as well as Nafion117 (1.31 × 104 S min cm−3). 相似文献