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131.
We deal with dynamic revenue management (RM) under competition using the nonatomic‐game approach. Here, a continuum of heterogeneous sellers try to sell the same product over a given time horizon. Each seller can lower his price once at the time of his own choosing, and faces Poisson demand arrival with a rate that is the product of a price‐sensitive term and a market‐dependent term. Different types of sellers interact, and their respective prices help shape the overall market in which they operate, thereby influencing the behavior of all sellers. Using the infinite‐seller approximation, which deprives any individual seller of his influence over the entire market, we show the existence of a certain pattern of seller behaviors that collectively produce an environment to which the behavior pattern forms a best response. Such equilibrium behaviors point to the suitability of threshold‐like pricing policies. Our computational study yields insights to RM under competition, such as profound ways in which consumer and competitor types influence seller behaviors and market conditions. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 365–385, 2014  相似文献   
132.
针对不同作战平台上多个武器单元对一批目标进行射击时的武器目标分配问题,建立了该问题的数学模型。采用混沌人工鱼群算法对动态条件下的武器目标分配问题进行求解,并设计一个实例进行仿真实验。仿真结果表明,在时间约束条件下该算法较遗传算法更具优越性,验证了混沌人工鱼群算法用于动态武器目标分配的有效性。  相似文献   
133.
利用粒子群优化算法和最小二乘支持向量机,建立了地球静止轨道高能电子通量(1.8-3.5MeV)在线预测模型。针对粒子群优化算法,提出了一种新的粒子群多样性测度计算方法,有效改善了其早熟收敛现象;基于改进的粒子群优化算法优化最小二乘支持向量机的正则化参数和核参数;利用滑动时间窗口策略更新模型数据,设计变量选择触发机制以及模型的再学习机制实现模型的在线预测功能。[根据题目的调整,对摘要做了相应改动]通过对2000年电子通量监测数据和相关太阳风、地磁参数等实际数据进行提前1-3天的预测实验,表明了所建在线预测模型具有较高的预测性能,有一定的实用价值。  相似文献   
134.
A critical issue for many governments is boosting the adoption rates of products or technologies that enhance consumer surplus or total social welfare. Governments may, for example, pay subsidies to producers or to consumers to stimulate the manufacture or consumption of specific products, for example, energy-efficient appliances or more effective drugs. This research proposes a strategic government investment policy, namely, share acquisition, and demonstrates its effectiveness in reaching societal objectives. We consider a Cournot quantities-choice market comprised of homogeneous firms where the government intervenes to buy shares, and turning private firms into state-owned enterprises. We recognize that purchasing a single private firm is the optimal policy for the government to reach its societal objectives. Additionally, taking into consideration financial constraints, we find that the optimal stake increases with the budget. Compared with the optimal output-based subsidy policy, when the budget is low, the optimal government investment policy induces a higher consumer surplus. In addition, in differentiated Cournot competition, under which firms compete in selling substitutable products, we find that when the budget is sufficient, the optimal stake purchased first decreases and then increases according to the substitutability level among products.  相似文献   
135.
Grand strategic theorists share an historical emphasis on interstate conflict, yet in contrast to the more frequent intrastate conflicts, these represent only 7 of the some 273 US military deployments since 1900. We argue that these intrastate conflicts limit the utility of regional balances of power in mitigating forms of conflict that the US may consider inimical to its national security interests. When considering potential changes to US force posture and grand strategy, American coercive statecraft should be theorised along a broader strategic continuum encompassing the full range of conflict.  相似文献   
136.
和谐社会语境下的宽严相济的刑事政策是传统的惩办与宽大相结合刑事政策的复归,它应当是新时期的基本刑事政策。任何刑事政策都应实践性地转化为刑法规范,宽严相济的刑事政策也应当加速其刑法化的进程。我国现行刑罚结构总体上存在着“当轻不轻“‘当重不重”的倒挂性局面,应尽快修改刑法来根本扭转刑罚轻重失衡的局面。宽严相济的刑事政策强调“宽”与“严”二者不可偏废,当下风行于刑法学界的一元的轻刑论应当为我们所摒弃。  相似文献   
137.
针对脉冲修正弹自身控制离散不连续特征,开展了脉冲修正弹脉冲控制参数优化设计方法研究。考虑到脉冲成本和精度的双重要求,选择以脉冲发动机工作次数和脱靶量最少为双目标函数,并在风干扰的条件下,提出了以脉冲控制时间间隔为离散脉冲控制参数设计变量建立优化模型,以此发展了一种改进型递减惯性权重粒子群优化脉冲控制参数的方法,提高了修正参数优化收敛速度。仿真结果表明,该算法能快速有效地获得最优解,为在干扰条件下寻找最优的脉冲修正参数和脉冲工作方式提供了一种优化设计思路。  相似文献   
138.
ABSTRACT

With the world’s ninth largest economy and comprising nearly 60% of South America’s GDP, 47% of its territory, and 49% of its population, Brazil has become a regional power and an important actor in world affairs over recent decades. This scenario has led the government to re-evaluate its role in the world order, resulting in the enactment of the National Defence Policy, whose objective was to consolidate the country as a regional power while at the same time addressing national security issues, promoting economic development through a series of defence programmes, restructuring the defence industrial base, fostering innovation through technology and knowledge transfer to Brazil, and indigenous research and development. However, the policy’s implementation suffers from several challenges discussed in this article, which may test the capability and competence of Brazilian policymakers, military, industrialists, and other individuals and organisations involved in its implementation.  相似文献   
139.
The 1981 Defence Review undertaken by John Nott as Secretary of State for Defence controversially and dramatically cut the capabilities of the Royal Navy’s surface fleet. Many of those involved in these decisions have emphasised the budgetary and politico-strategic drivers for these reductions in capability, and the first generation of academic analysis has broadly followed this position. However, recently released government and private archival sources demonstrate that Nott’s review was initially much more severe than thought, and that this was due as much to the presumptions and assumptions of the key decision makers as to any strategic or budgetary factors.  相似文献   
140.
有限次故障小修模型   总被引:1,自引:1,他引:0  
针对具有小修的维修策略问题,在提出一定的假设条件后,建立经过长期运行后的单位时间期望损失的模型,研究并分析了有限次故障小修模型,最后通过相应的示例验证了研究结果。  相似文献   
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