基于网络的物资招标采购系统的开发与应用

以某大型机械制造企业的招标采购管理为背景 ,介绍了基于网络的物资招标采购系统的系统构架、系统功能、开发模式以及系统特点。该系统实现了物资招标采购活动的电子化过程控制 ,加强了供应链上各企业间的信息传递 ,为企业物资招标系统的开发提供了可借鉴的经验     

反相微乳法合成淀粉微球的研究

以可溶性淀粉为原料,环氧氯丙烷为交联剂,Span60为乳化剂,植物油为油相,采用反相微乳法合成淀粉微球.以吸附量为指标进行正交试验,得到淀粉微球的最佳合成条件为：淀粉浓度14%、油相用量100 mL、乳化剂用量0.75 g、交联剂用量4.8 mL、搅拌速度1 200 r/min.利用红外光谱和电子显微镜对产物进行表征,证明了可溶性淀粉与环氧氯丙烷发生了交联反应.     

超超临界1000MW机组自起停控制系统

以海门电厂1000 MW机组为例,介绍了其自起停控制系统(APS)的设计、系统结构及功能。APS可使机组按照程序自动起停设备,降低了误操作率,缩短了机组起动时间,提高了机组运行的安全性和经济性。在APS设计中,合理地设置程序断点是实现APS功能的关键。     

重庆市竞技体育的发展战略

采用调查访问法、文献资料法等，对重庆市竞技体育的发展状况、有利条件与制约因素进行了分析研究，探讨了实现重庆市竞技体育发展的战略途径与对策，针对重庆市竞技体育的管理体制、竞技体育人才、资金投入、体育设施等方面存在的问题提出了具体的改进措施。     

Clustering analysis of ancient celadon based on SOM neural network

In the study, chemical compositions of 48 fragments of ancient ceramics excavated in 4 archaeological kiln sites which were located in 3 cities (Hangzhou, Cixi and Longquan in Zhejiang Province, China) have been examined by energy-dispersive X-ray fluorescence (EDXRF) technique. Then the method of SOM was introduced into the clustering analysis based on the major and minor element compositions of the bodies, the results manifested that 48 samples could be perfectly distributed into 3 locations, Hangzhou, Cixi and Longquan. Because the major and minor element compositions of two Royal Kilns were similar to each other, the classification accuracy over them was merely 76.92%. In view of this, the authors have made a SOM clustering analysis again based on the trace element compositions of the bodies, the classification accuracy rose to 84.61%. These results indicated that discrepancies in the trace element compositions of the bodies of the ancient ceramics excavated in two Royal Kiln sites were more distinct than those in the major and minor element compositions, which was in accordance with the fact. We argued that SOM could be employed in the clustering analysis of ancient ceramics. Supported by the Research Foundation of City University of Hong Kong (Grant No. 7001104)     

Improved Reliability Performances of SONOS-Type Devices Using Hot-Hole Erase Method by Novel Negative FN Operations

Several novel negative Fowler-Nordheim (FN) operations for hot-hole-erased SONOS-type devices are studied. By using p⁺-poly gate instead of n⁺-poly gate, gate injection is greatly suppressed, and the device shows self-convergent V_T after -FN. By using this self-converging property, -FN operation can be applied to both erased and programmed states in various sequences/algorithms. In the erase state, a short -FN channel erase called "soft erase" can be performed after hot-hole sector erase. It provides a strong electrical annealing effect to recover the hot-hole damages. On the other hand, "refill" is a shorter version of the soft erase method that expels shallow-level electrons and replaces them with deeper level ones. A spectrum blue shift model is proposed to explain the shifting of the trapped-electron energy distribution to a bluer (deeper) spectrum during refill. Various soft erase and refill conditions are examined to study the charge loss mechanism. The experimental results exhibit superior retention by combining the suitable soft erase and refill conditions. We find that the vertical charge losses measured by V_G -accelerated retention test at room temperature (25 degC) are highly correlated to that measured at high temperature baking (150 degC), and a reliability model is proposed to explain these mechanisms.     

Device modeling of ferroelectric memory field-effect transistor for the application of ferroelectric random access memory

An improved theoretical analysis on the electrical characteristics of ferroelectric memory field-effect transistor (FeMFET) is given. First, we propose a new analytical expression for the polarization versus electric field (P-E) for the ferroelectric material. It is determined by one parameter and explicitly includes both the saturated and nonsaturated hysteresis loops. Using this expression, we then examine the operational properties for two practical devices such as the metal-ferroelectric-insulator-semiconductor field-effect transistor (MFIS-FET) and metal-ferroelectric-metal-insulator-semiconductor field-effect transistor (MFMIS-FET) as well. A double integral also has been used, in order to include the possible effects due to the nonuniform field and charge distribution along the channel of the device, to calculate the drain current of FeMFET. By using the relevant material parameters close to the (Bi, La)/sub 4/Ti/sub 3/O/sub 12/ (BIT) system, accurate analyses on the capacitors and FeMFET's at various applied biases are made. We also address the issues of depolarization field and retention time about such a device.     

Hybrid Dirac semimetal-based photodetector with efficient low-energy photon harvesting

Despite the considerable effort, fast and highly sensitive photodetection is not widely available at the low-photon-energy range (～meV) of the electromagnetic s...     

单相大容量核电变压器漏磁场及局部过热研究

本文中作者对单相超大容量核电变压器由漏磁产生的损耗和结构件温升计算方法进行了研究,通过实测值和计算值的对比,验证了本文提出的计算方法的正确性。     

基于多指标体系的10kV配电网投资分配评价

随着配电网投资规模逐步加大,亟需确立一套评价配电网投资分配合理性的指标和方法。从安全性、可靠性、经济性、灵活性、协调性和环境影响性6方面建立了10 kV配电网投资分配评价指标体系。采用模糊数学综合评价方法进行10 kV配电网投资分配的综合评价。为了兼顾客观数据以及投资分配者对各数据重视程度对指标权重的影响,采用基于盲数理论的赋权法进行指标赋权。对我国东南某省电力公司2010、2011年10kV配电网投资分配结果进行了评价,评价结果显示其分配结果较为合理。