AN EXCESS INVENTORY MODEL OF DETERIORATING ITEMS TAKING ACCOUNT OF PRESENT VALUE

In this study, both deterioration and present value are considered to derive an economic time supply when there is excess inventory. An excess inventory model is developed for a deterministic perpetual inventory system. Our goal in this research is to maximize the net benefit during the infinite planning horizon. Numerical examples are provided lo illustrate the theory, ft is demonstrated that the percentage of extra net benefit when present value is considered is at least 24%. The percentage of the extra net benefit when deterioration is considered is over 16%. When both present value and deterioration are considered, the net benefit increase is over 50%. Thus the consideration of present value and deterioration is significant.     

窗墙比对室内热舒适性指标PMV影响的研究

通过建立数学模型进行数值模拟计算,在相同节能改造方案下,对窗墙比与热舒适性之间的变化关系进行了研究。研究表明:窗墙比为0.2时室内舒适性指标较高,但窗墙比为0.32和0.4时的室内舒适性指标基本相同,而且窗墙比为0.32时的室内舒适性指标稍小于窗墙比为0.4时的室内舒适性指标,这与通常窗户越小越舒适的说法有所不同。     

产业链“波粒二象性”研究——论产业链的特性、结构及其整合

由于对产业链特性认识不清，产业链的研究总是处于夹缝之中，依附于产业或企业的研究。正如光既不是“波”也不是“粒子”一样，产业链实际上是一个具有“波粒二象性”的特殊产业组织。它的结构也不是通常的产业纵向关联形式，而是类似“玻尔原子”结构式的企业关联状态。这种特性和结构就决定了产业链研究的核心问题是如何整合产业链，完成产业创新和实现产业价值。解决的主要思路就是根据产业链的“波粒二象性”来调控产业链间的企业关系，促进产业链条的优化。特别是在企业之间形成“量子纠缠”．推动“量子跃迁”。“量子纠缠”是为了无形“隐性知识”在产业链条中的“隐性传输”．“量子跃迁”是为了有形“中间产品”在产业链条间的“显性传输”。     

酸性离子液体[Emim]HSO4催化合成丁二酸二乙酯

采用两步法合成并表征了酸性离子液体[Emim]HSO4,并用于催化合成丁二酸二乙酯,考察了醇酸物质的量比、反应时间、反应温度、催化剂用量对酯收率的影响。其最佳工艺条件如下:n(乙醇)∶n(丁二酸)=3∶1、反应温度为70℃、反应时间为4h、催化剂用量为总质量的5%。在此最佳反应条件下酯收率可达75.02%。考察了酸性离子液体重复使用性能,离子液体重复使用7次后,催化活性基本不变。     

Valuation and Efficiency in the Market for Creatively Financed Houses

This paper examines two alternative approaches to valuing the impact of creative financing on housing prices. The cash equivalence adjustment which is the generally accepted approach is compared to an approach known as the financed fee valuation adjustment which is argued to be theoretically superior. A sample of 45 matched pairs of condominium sales in which one of the units is creatively financed and the other is conventionally financed is employed to test which model is most effective at explaining the market adjustment for creative financing. The authors are unable to reject the hypothesis that the housing market being examined is efficient and that the financed fee valuation adjustment is a superior model for valuing the impact of creative financing.     

高效液相色谱法测定盐酸咪唑苯脲的含量

建立了高效液相色谱法测定盐酸咪唑苯脲的含量。采用Amethyst C18色谱柱(4.6mm×150mm,5μm);以乙腈-缓冲液(缓冲液为5mmol/L辛烷磺酸钠溶液,含0.1%(体积分数)三乙胺,用冰乙酸调节pH值为3.2)为流动相,乙腈与缓冲液体积比为30︰70;流速为1.0mL/min;检测波长为239nm;柱温为30℃。在39.32～137.62μg/mL范围内,盐酸咪唑苯脲峰面积与质量浓度呈良好的线性关系(r=0.999 3),平均回收率约为99.50%(n=9),RSD值约为0.52%。     

On the role of verifiability and commitment in credence goods markets

A client has a problem, but does not know whether it is serious or minor. She consults an expert who can correctly diagnose and fix her problem. This paper characterizes the equilibrium pricing and recommendation strategies of an expert under the assumptions that i) the type of treatment is verifiable by the client, ii) the client has the option of rejecting any treatment recommendation, and iii) the expert is not liable for the outcome of the treatment. It is found, for any parameter configuration, that there exist equilibria in which the expert makes fraudulent recommendations resulting in inefficient treatment. The market outcome is compared with that under an alternative market environment in which the expert is liable for treatment outcome but the type of treatment performed is non-verifiable. It is shown that for some parameter configurations the equilibrium is more efficient when liability is in place than when the treatment is verifiable. These findings stand in sharp contrast to the received wisdom that the market outcome under verifiability of treatment is efficient while the market outcome under liability for outcome is not. Finally, this paper shows that the existence of some honest experts may induce more fraudulent behavior by opportunistic experts.     

Centralized and Decentralized Contracts in a Moral Hazard Environment

We study the optimal allocation of the contracting capacity in a moral hazard environment. Centralizing is superior when the principal is able to establish all the contracts with the agents simultaneously and she is able to monitor side contracting between the agents. Otherwise, decentralizing can be a superior strategy. We apply our results to a firm's decision on which outlets to franchise. They suggest that franchising is more likely to occur the further the store is from headquarters, the more isolated it is and in those activities where the risk is low. This conclusion is consistent with empirical studies.     

GNSS抗干扰中LCMV算法研究及仿真

由于GNSS卫星信号强度极小,容易受到强信号干扰,针对如何有效抗干扰问题,将基于功率倒置天线阵列LCMV算法在一定的数学模型基础上利用理论进行推演,并稍加改进避免了矩阵求逆,然后通过Matlab仿真加以验证,最后为该算法的实现进行了硬件设计。提出了以FPGA结合DSP的处理方案,利用FPGA完成射频采集,由DSP进行抗干扰处理以及LCMV算法实现。     

QC小组运行的有效方法

结合生产实际，从6方面阐述了大庆油田公司如何使QC小组有效运行的方法：全员参与是QC小组有效运行的前提；素质培养是QC小组有效运行的基础；过程管理是QC小组有效运行的保证；探索创新是QC小组有效运行的关键；奖励机制是QC小组有效运行的手段；成果推广转化是QC小组有效运行的价值体现。     

论能源新形势下的我国节能认证活动

能源问题是全球共同关注的一个战略性问题。我国是能源消费大国,能源需求大,而国内能源贮备不足,节能任务十分迫切。为适应新形势下的节能需要,我们建议应采取节能认证的手段,大力促进节能工作的发展。     

Base-stock policies for the lost sales inventory system with Poisson demand and Erlangian lead times

The base-stock policies for the studied inventory system can easily be evaluated through Erlang's loss formula when the lead times are mutually independent. This is often the case only if the base-stock $S$ is one. If $S$ is larger than one, the Erlangian lead times become stochastically dependent under the realistic assumption that the replenishment orders do not cross in time. We make this assumption and show for any positive $S$ that the number of replenishment orders outstanding has an equilibrium distribution which is a slightly modified truncated version of a negative binomial distribution. It turns out to be easy to compute the stock-out frequency recursively for $S=1,2,\dots .$ For each $S$, the average stock can be specified in terms of this frequency. We prove that the frequency is convex in $S$. It is therefore straightforward to compute the base-stock for which the average cost is minimized and to compute the minimum average cost. Our numerical study illustrates that the minimum average cost is very sensitive to the shape parameter describing the Erlangian lead times, which is in sharp contrast to the complete insensitivity when lead times are independent.     

水产品中孔雀石绿及其代谢物快速检测方法研究

建立一种简便、快速的检测水产品中孔雀石绿及其代谢物残留量的方法。采用乙腈提取、固相萃取柱净化浓缩,氧化剂将隐性孔雀石绿氧化为孔雀石绿,用化学比色法观察结果,从而建立一种简便、快速的初筛方法。加标回收率为70%～95%,相对标准偏差为5.46%～9.90%,孔雀石绿及代谢物的检出限分别为2μg/kg和4μg/kg。本方法相对于国标法操作更简便快速,适用于大批量样品检测。     

风网互补技术在丛式井组的应用探讨

介绍了长庆油田地区风能资源测试、统计和分析的方法,得出了长庆油田基本位于风能可利用区的结论;针对长庆油田现状,提出了分布式风网互补供电系统在油田丛式井组上应用的方案;并对风力发电进行了效果测试分析。     

基于T-S模型的一类时滞非线性系统模型预测控制

针对具有状态时滞特性的非线性离散系统,利用线性矩阵不等式的方法和Lyapunov稳定性理论,研究了基于状态反馈的非线性系统模型预测控制问题。基于T-S模糊模型对非线性离散系统进行描述并给出一种"min-max"预测控制算法,采用模型预测控制与模糊理论相结合的方法,利用平行分布补偿的原理,通过在每一个采样时刻优化无穷时域的性能指标,来求解在范数有界条件下相应的状态反馈控制律,讨论了预测控制器的设计问题,分析了此设计问题的可解性,给出了状态反馈控制器基于线性矩阵不等式的设计算法,保证了系统的稳定性,通过仿真实例证明了所提控制算法的有效性及系统的稳定性。该方法能够在化工、冶金、机械等具有时滞特性的工业生产过程中得到很好的应用。     

企业质量文化初探

介绍了质量文化建设的内涵,包括质量观念(理念)文化、质量行为准则、质量体系建设文化、质量创新质量文化、质量品牌战略文化、质量宣教培训文化。就如何培育优良的质量文化进行了初步的探讨,指出,"质量是企业的生命"的观念是质量文化建设的灵魂;领导观念创新是质量文化建设的关键;质量方针是质量文化建设的核心;质量管理创新是质量文化建设的源泉;质量品牌经营是质量文化建设亮点;实施卓越绩效管理模式是质量文化建设的动力;用户满意是质量文化建设的目标。     

德国金融危机救援行动的评析及对中国的启示

德国经济受到了金融危机的严重影响,但其经济体系未遭受根本性破坏,其重要原因之一是德国采取了比较有效的经济救援措施。一是金融救市计划,主要用于救助银行,稳定金融市场:二是先后出台的两套经济刺激计划,主要用于劳动市场促进、直接公共投资、以旧换新的汽车置换补贴。德国的经济救援行动主要遵从了四条基本准则:一是政府有限参与的准则:二是维护市场机制的准则;三是遵循现有政策框架的准则;四是强调政策及时性的准则。中国在4万亿元的经济刺激计划中,应当实现三个转变:①从注重应对危机的短期手段向注重完善市场机制的长期战略转变;②从关注公共投资数量向关注公共投资效益转变;③从单纯的减税和降息向改善企业经营环境转变。     

流管法天然裂缝性低渗透油藏数值模拟研究

天然裂缝性低渗透砂岩油藏开发潜力巨大,进行相关数值模拟研究对于保证油田高产稳产具有重要的意义。为实现天然裂缝性低渗透油藏的快速数值模拟研究工作,以反九点井网为例建立概念模型,运用流管法结合等效连续介质模型进行数值模拟研究,绘制渗流模板,建立适合天然裂缝性低渗透砂岩油藏的数值模拟研究方法。将流管法应用于实际区块开展数值模拟研究,与常用软件模拟结果对比,发现流管法结合等效连续介质模型适用于天然裂缝性低渗透油藏的数值模拟研究工作。     

网络组织视角下产业集群社会责任建设研究

产业集群是产业网络诸多组织形态中的一种。由于地理临近性和紧密的网络关系,集群内企业的社会责任不再是一种"个体行为",从产业集群层面寻求合作共赢而共同推进社会责任建设已经成为必然趋势。因而,本文引入"网络组织"分析视角,提出了"产业集群社会责任"的概念。在此基础上,提出了基于"Hub节点企业"助推的产业集群社会责任"层级建设"模式,首先利用网络分析工具,构建产业集群Hub节点企业识别指数,继而提出遵循产业集群"点式—链式—网式"社会责任建设的层级推进模式。     

2，3-环戊烯并吡啶的气相色谱分析

通过对色谱分离条件的优化,建立了2,3-环戊烯并吡啶的气相色谱分析方法。色谱条件为SE-30毛细管色谱柱(25 m×0.22 mm×0.25μm);载气(N2)流速为1.0 mL/min;柱温为130℃;进样器温度为200℃;分流进样模式,分流比为100∶1。对合成样品进行了测定,线性回归方程为A=440.84c+33 088,r=0.999 3,线性范围为2~500 mg/L,方法的检出限为0.2 mg/L,平均回收率为99.4%,相对标准偏差为1.30%。