甲基三硫代膦酸二乙酯合成反应液的气相色谱-质谱分析

在OPCW第18次水平考试土样中检测到一未知化合物,经多种分析技术测定,判断可能是甲基三硫代膦酸二乙酯．对合成甲基三硫代膦酸二乙酯的反应液进行了气相色谱一质谱测定,并对此反应液中的部分产物进行了质谱解析．     

循环经济与可持续发展

循环经济和知识经济并称为21世纪发展新亮点,也是世纪之交人类社会可持续发展的两大趋势。人类社会在经历了漫长的发展历史之后,正处于一种大量的资源、能量的耗费,大量的废物进入生存环境的状态,自然环境一次又一次向人类敲响警钟。本文试从循环经济这一视角来对其与可持续发展的问题进行探讨。     

论陈毅军旅诗的人格魅力

陈毅素有“一代儒将”,“元帅诗人”之美誉,他的诗作多达350余篇,在社会上广为流传,其作品以大气磅礴的风格和正直不阿的人格著称。本文撷取陈毅军旅诗的名篇,从坚贞不渝的革命气节、不畏艰险的英雄气概、爱憎分明的坦荡胸怀等三个方面阐发陈毅诗词的人格魅力。     

瞿秋白武装斗争思想形成的历史考察

瞿秋白武装斗争思想的形成发展经历了三个历史阶段:1919年至1925年“五卅运动”是其萌芽时期;1925年“五卅运动”后至1927年“八七会议”前,是其基本形成时期;1927年“八七会议”至1931年1月中共六届四中全会,是其成熟时期。就其形成原因来看,旅俄经历是首要原因,中国革命斗争发展的实际需要是客观原因,担任党的主要领导人是主观原因。瞿秋白武装斗争思想是我党历史上较早对武装斗争问题给予重视和阐述的一个重要理论成果。     

解放战争时期中共遏制美国介入中国内战之探析

解放战争时期,中国共产党全面分析第二次世界大战后国内外形势,利用强大的苏联、东欧人民民主国家的存在,及东方被压迫民族反殖民主义风起云涌的斗争等有利国际形势,克服党内军内惧怕美国的思想,认真考量对美斗争的策略,尽可能减小并最终遏制了美国卷入中国内战的可能性。     

非线性评估中权重的敏感性分析

分析了非线性评估中权重的敏感性问题,给出了分析的思路和计算方法,并得出判断权重敏感的方法,定义了多维权重的敏感度,并由算例说明评价值的敏感性和权重的关系.     

面向新化学威胁形式的防护技术与装备

近年来,化学威胁的形式发生了变化,出现了类化学战、化学恐怖以及针对平民和环境的次生危害,给防化科研和防化工作提出了新的挑战。分析传统化学战与这三类新化学威胁形式的异同点发现,这些新威胁形式之间有着较多的共同点,而与传统化学战威胁形式则有较大差异。中国拥有为数众多的大型化工生产、储存设施,这些设施很可能成为袭击的目标,因此必须转变化学防护观念,尽快研究防化新技术、新装备,建立国家动员机制。     

Optimal replacement of continuously degrading systems in partially observed environments

Motivated by wind energy applications, we consider the problem of optimally replacing a stochastically degrading component that resides and operates in a partially observable environment. The component's rate of degradation is modulated by the stochastic environment process, and the component fails when it is accumulated degradation first reaches a fixed threshold. Assuming periodic inspection of the component, the objective is to minimize the long‐run average cost per unit time of performing preventive and reactive replacements for two distinct cases. The first case examines instantaneous replacements and fixed costs, while the second considers time‐consuming replacements and revenue losses accrued during periods of unavailability. Formulated and solved are mixed state space, partially observable Markov decision process models, both of which reveal the optimality of environment‐dependent threshold policies with respect to the component's cumulative degradation level. Additionally, it is shown that for each degradation value, a threshold policy with respect to the environment belief state is optimal if the environment alternates between two states. The threshold policies are illustrated by way of numerical examples using both synthetic and real wind turbine data. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 395–415, 2015     

Selling to strategic and loss‐averse consumers: Stocking,procurement, and product design policies

Motivated by the presence of loss‐averse decision making behavior in practice, this article considers a supply chain consisting of a firm and strategic consumers who possess an S‐shaped loss‐averse utility function. In the model, consumers decide the purchase timing and the firm chooses the inventory level. We find that the loss‐averse consumers' strategic purchasing behavior is determined by their perceived gain and loss from strategic purchase delay, and the given rationing risk. Thus, the firm that is cognizant of this property tailors its inventory stocking policy based on the consumers' loss‐averse behavior such as their perceived values of gain and loss, and their sensitivity to them. We also demonstrate that the firm's equilibrium inventory stocking policy reflects both the economic logic of the traditional newsvendor inventory model, and the loss‐averse behavior of consumers. The equilibrium order quantity is significantly different from those derived from models that assume that the consumers are risk neutral and homogeneous in their valuations. We show that the firm that ignores strategic consumer's loss‐aversion behavior tends to keep an unnecessarily high inventory level that leads to excessive leftovers. Our numerical experiments further reveal that in some extreme cases the firm that ignores strategic consumer's loss‐aversion behavior generates almost 92% more leftovers than the firm that possesses consumers’ loss‐aversion information and takes it into account when making managerial decisions. To mitigate the consumer's forward‐looking behavior, we propose the adoption of the practice of agile supply chain management, which possesses the following attributes: (i) procuring inventory after observing real‐time demand information, (ii) enhanced design (which maintains the current production mix but improves the product performance to a higher level), and (iii) customized design (which maintains the current performance level but increases the variety of the current production line to meet consumers’ specific demands). We show that such a practice can induce the consumer to make early purchases by increasing their rationing risk, increasing the product value, or diversifying the product line. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 435–453, 2015     

Optimal and asymptotically optimal policies for assemble‐to‐order n‐ and W‐systems

We consider two specially structured assemble‐to‐order (ATO) systems—the N‐ and W‐systems—under continuous review, stochastic demand, and nonidentical component replenishment leadtimes. Using a hybrid approach that combines sample‐path analysis, linear programming, and the tower property of conditional expectation, we characterize the optimal component replenishment policy and common‐component allocation rule, present comparative statics of the optimal policy parameters, and show that some commonly used heuristic policies can lead to significant optimality loss. The optimality results require certain symmetry in the cost parameters. In the absence of this symmetry, we show that, for systems with high demand volume, the asymptotically optimal policy has essentially the same structure; otherwise, the optimal policies have no clear structure. For these latter systems, we develop heuristic policies and show their effectiveness. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 62: 617–645, 2015