176 research outputs found

    Study on Operations Strategy of FP Company

    Get PDF
    论文摘要 运作战略是运作管理中最重要的组成部分之一,它是企业战略在运作领域的细化,是从运作的角度对企业战略的支持和体现,同时也是企业运作系统及管理的指导纲领,其最终目的是提升企业的生存竞争力。 本文基于运作管理相关理论,针对中国电子变压器行业和FP公司发展的历史与现状以及存在的主要问题,利用PEST、五力模型、SWOT和价值链等分析工具,比较系统、深入地分析了FP公司的内、外部环境因素以及运作竞争的重点,进行了FP公司的运作战略规划,提出了生产运作系统的使命、生产组织方式和生产运作目标,并对FP公司运作战略的具体实施包括设计支持企业运作竞争重点的运作系统、重塑支持企业战略的文化、变革组...Abstract Operations strategy is one of the most important parts of operations management. It is the refinement of company strategy in the field of operations . It is a support to the company strategy from the perspective of operations and is meanwhile the guideline of the company operations and management system with the ultimate target of raising the competitiveness of a company. On the basis o...学位:工商管理硕士院系专业:管理学院工商管理教育中心(MBA中心)_工商管理硕士(MBA)学号:X200515512

    Conversion of Biomass into Levulinate Esters as Novel Energy Chemicals

    Get PDF
    生物质是唯一可替代化石资源获取液态燃料和化学品的可再生资源,近年来由生物质转化合成乙酰丙酸酯引起了研究者们越来越广泛的关注。乙酰丙酸酯是一类重要的化学中间体和新能源化学品,具有高的反应特性和广泛的工业应用价值。目前开发的从生物质资源出发转化合成乙酰丙酸酯的潜在合成途径可概括为4种:直接酸催化醇解法、经乙酰丙酸酯化、经5-氯甲基糠醛醇解和经糠醇醇解。本文分别介绍了这4种转化合成途径的化学反应过程及最新研究进展,从反应合成工艺、催化体系、经济可行性等方面评述了各自的特点与发展趋势,并分析了目前工业规模转化生物质合成乙酰丙酸酯仍面临的一些科学难点。最后,对今后该领域的研究前景进行了展望。Biomass is the only renewable resources on the earth that can derive liquid fuel and fine chemicals to replace the petroleum-based chemicals.In recent years,the development of bioenergy concerning the synthesis of levulinate esters from biomass via chemical/catalytic process has attracted more and more concerns,and extensive research is being carried out worldwide.Levulinate esters,like methyl levulinate,ethyl levulinate,and butyl levulinate,are a kind of important intermediates and energy chemicals having high reactivity and widespread application in many fields.Up to now,there are four developed potential pathways for the synthesis of levulinate esters from biomass conversion,including the direct acid-catalyzed alcoholysis of biomass,the esterification of levulinic acid that from hydrolysis of biomass,the alcoholysis of 5-(chloromethyl)furfural derived from biomass,and the alcoholysis of furfuryl alcohol that from hydrogenation of furfural.In this review,the chemical reaction process and recent research progress for the above four pathways are introduced.The characteristic and development tendency of these pathways are reviewed from the production process,catalytic system and economic feasibility.Based on the present research situation,the technology and engineering barriers for the conversion of biomass to levulinate esters in commercial scales are analyzed and discussed,and the future research trend in the field is prospected.国家重点基础研究发展计划(973)项目(No.2010CB732201);国家自然科学基金项目(No.50776035);中央高校基本业务费专项资金项目(No.2010121077)资

    企业典型产品生命周期曲线的Logistic随机模型的拟合与应用

    Get PDF
    对企业产品生命周期的识别、特别是对典型产品生命周期的识别构成了产品生命周期理论的基础和难点。虽然lOgISTIC模型可用于产品生命周期的识别,但由于该模型参数的非线性性,在估计方法上存在一定困难。文章结合三段倒数和值法与fISHEr-Pry变换对典型产品生命周期的lOgISTIC随机模型进行拟合,并给出实证分析结果。不仅从曲线特征上适用于拟合典型产品生命周期,同时又满足了反映经济现象随机性特性的要求。教育部人文社会科学2007年度重大项目(07JJD790145

    基于Alamouti编码方案的多天线系统的BER性能研究

    Get PDF
    分析了采用Alamouti编码方案(ACS)的两发射天线和多接收天线系统(2Tx mRx)的工作原理,介绍了传输符号分离的一般分析方法。在平坦衰落信道中,导出了系统传输MPSK调制信号的比特误码率理论式。从理论上证明了采用ACS的2Tx mRx系统与同阶MRC接收分集有相同的分集增益。对最大似然(ML)判决估计器给出了易于理解和实现的仿真算法。理论和仿真结果均表明:ACS与相同的最大比合并(MRC)分集阶数的性能一样

    永磁同步电机混沌系统的单输入反馈全局指数稳定控制

    Get PDF
    针对永磁同步电机混沌系统,结合Lyapunov稳定性与比较原理理论,分别对参数确定和参数不确定的永磁同步电机混沌系统提出一种单输入线性反馈全局指数稳定控制器.该控制器不仅结构简单,而且可以通过调整指数收敛速率,实现永磁同步电机混沌系统的全局指数稳定控制.分别对参数确定与参数不确定的永磁同步电机混沌系统进行数值模拟,进一步验证了所提方案的有效性.福建省教育厅中青年教师教育科研项目(JAT170091)福建省自然科学青年基金(2019J05024)福州大学科研启动项目(XRC-17028

    应用光合色素标记物研究2001年2~6月厦门西海域浮游植物群落结构

    Get PDF
    利用反相高效液相色谱(RP-HPLC)对厦门西海域2001年2~6月的浮游植物色素进行了测定,并首次运用CHEMTAX软件对该海域进行了浮游植物群落组成的分析,同时分析了环境因子对群落组成的作用.我们首先改进了RP-HPLC分离方案,分离的时间缩短了近1/3,达到了提高分离效率的目的.利用改进后的RP-HPLC方案进行色素分析显示,厦门西海域2001年2~6月期间,主要的特征色素是岩藻黄素(fucoxanthin)、19’-丁酰基氧化岩藻黄素(19’-butanoyloxyfucoxanthin)、19’-己酰基氧化岩藻黄素(19’-hexanoyloxyfucoxanthin)和多甲藻素(peridinin),月平均含量分别在267.824~655.076、20.118~126.764、65.693~214.115、26.955~203.927μg/m3的范围变动.CHEMTAX计算的结果进一步表明:硅藻是主要优势类群,其次是定鞭金藻和甲藻,分别占总生物量的36.14%~79.27%、4.50%~37.40%和4.83%~21.37%.总生物量从2月到6月呈增长趋势,温度是主要的决定因子.硅藻和定鞭金藻所占生物量的份额呈相反趋势变化,表明种间竞争也是重要的因素之一

    Surface texture analysis for ultra-precision flycutting machining based on the dynamic characteristics of machine tools

    Get PDF
    采用超精密飞切加工技术可获得软脆性平面光学元件的最终表面,而元件表面微观形貌的加工可控性对于光学元件使用性能有直接影响。首先运用多尺度小波分解方法,对飞切机床的加工表面波纹进行了特征提取,得到了工件表面波纹的频率组成及占比;然后通过对机床主轴系统的有限元分析,结合冲击振动测试,找到了与工件表面波纹对应的模态;最后通过对机床的在线振动测试及加工实验进一步明确了飞切加工表面微波纹的成因。结果表明:表面波纹在17 mm左右的空间周期上存在最大的分量,显著影响光学元件的精度和使用效果,该波纹由主轴系统在间断切削的冲击响应所引起,可以通过改变主轴结构实现波纹频率和幅值的控制。Ultra-precision flycutting is widely used to machine soft and brittle plane optical elements,and the controllability of micro surface texture affects the performance of the element directly. The multi-scale wavelet decomposition was used to detect the wave feature of the optical element machined by flycutting machine tool,and the frequency and percent of the waves were achieved. The relevant modals of those waves were found by the finite element analysis and the response test of the spindle system. Particularly,online vibration test and machining experiments were conducted to verify the factor bringing about the micro surface texture on the element. The results show that the micro surface texture at a space period of 17 mm is the most prominent and will make worse observably the accuracy and application of the element,which is caused by the response of the spindle system during the machining process. In addition,modifying the structure of spindle system can make a difference on the amplitude and frequency of the wave.国家级基金(2013ZX04006011-102-001

    退火温度对Cu_(NPs)@ZnO纳米复合薄膜结构与光学性能的影响

    Get PDF
    使用磁控溅射结合惰性气体冷凝的方法制备了Cu纳米粒子,通过将Cu纳米粒子沉积与ZnO离子束溅射原位复合的方法制得了CuNPs@ZnO纳米复合薄膜,并研究了退火温度对CuNPs@ZnO纳米粒子复合薄膜的结构和光学性能的影响。通过对样品的表征发现所得产物中存在着低温条件下难以形成的立方相、岩盐结构的ZnO。并且,样品的微观形貌、结晶性和光学性能随着退火温度的变化而发生显著地变化

    包埋固定化EM菌的氨氮去除特性研究

    Get PDF
    采用PVA-硼酸包埋固定化EM菌,在好氧、批式运行条件下,系统考察不同的工艺参数对固定化EM菌的氨氮去除性能的影响。结果表明:用PVA-硼酸包埋法固定EM的小球对氨氮的去除是EM生物降解、包埋小球自身吸附的共同结果;以贝壳粉末作为添加剂、包埋离心后的EM有利于提高包埋小球的强度及脱氨效果。经过6个运行周期,氨氮的去除率可达到90%以上;较多EM包埋量仅在运行初期有助于提高脱氨效果,长期使用PVA小球时的最适宜的EM包菌量体积比为10∶3

    Investigation of the Association Between Bovine Serum Albumin(BSA) and Aluminum Tetrasulfonated Phthalocyanine(AlS4 Pc) by Fluorescence Anisotropy

    No full text
    Fluorescence anisotropy was employed for the investigation of the association between AlS 4Pc and BSA.The average binding number of AlS 4Pc to BSA was calculated and the constants of association reaction occurring in the medium of pH 7 0 were shown.The results revealed that the interaction between AlS 4Pc and BSA was strong, which implied that AlS 4Pc may be stored and transferred by serum albumin.The merits of the method used were also pointed out.国家自然科学基金!(批准号:29775021)资
    corecore