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31.
PC软件产品竞争性升级的定价研究   总被引:1,自引:1,他引:1       下载免费PDF全文
通过Hotelling模型对PC软件产品竞争性升级进行了研究,重点分析了网络外部性、转换成本、升级产品质量(或功能)的提高对升级定价及其竞争策略的影响.主要成果包括以下几个方面(1)在消费者静态预期的条件下,网络规模大的厂商总是偏好不兼容,网络规模小的厂商偏好全兼容.(2)分析了影响版本升级价格、竞争性价格和全价的相关因素.(3)解释了转换成本和实施竞争性升级的关系.(4)分析了厂商夺取竞争对手厂商客户的条件以及争夺新客户的竞争策略.对厂商的竞争性升级定价具有重要的理论指导意义.  相似文献   
32.
非畅流流域跨界水污染纠纷管理模型研究   总被引:4,自引:0,他引:4       下载免费PDF全文
结合我国流域的非畅流特点,提出了流域各地区作为独立决策单元、污染物人为调控和地区间污染物间接不影响等几个基本假设,构建了我国流域跨界水污染描述模型.分析了我国目前正在执行的污染物削减指令配额模型的优缺点,提出用行政、税收、排污权交易等手段解决我国日益严重的流域跨界水污染纠纷问题,为此建立了合作协调模型、税收宏观调控模型、排污权交易宏观调控模型.通过对淮河流域跨界水污染纠纷的具体应用分析了各种管理模型的资源利用效率.最后,通过各种管理模型的对比分析,指出选择合适的管理模型应与流域的实际情况相匹配.  相似文献   
33.
自组织建模方法和GDP增长模型研究   总被引:9,自引:3,他引:9  
经济系统的复杂性决定了经济变动及影响因素解释的困难性。本文阐述了一种经济系统复杂性研究的有效方法-自组织建模方法,同时应用此方法建立一个解释我国GDP增长的自组织模型,分析影响我国经济增长的主要因素,并在此基础上提出相应的对策思路。  相似文献   
34.
在食品安全威胁下,农户重新定义了“为自家生产”和“为市场生产”的差别化生产行为。基于经济理性行为假设认为农户存在以确保自家食品安全为动机的生存理性。根据在5省区收集的827份农村入户调研数据,对农户差别化生产行为进行具体分析,描述了差别化生产行为总体特征,并测量农户食品安全自我保护意识、威胁感知程度和信息渠道等因素。运用Probit模型验证了命题:以食品安全自我保护意识为特征的生存理性,支配了农户为确保自家消费安全而进行的差别化生产。  相似文献   
35.
ProblemWomen commonly experience emotional distress following miscarriage but do not receive the support they need from healthcare providers.BackgroundMiscarriage can result in psychological morbidity; however, appropriate support at the time of a miscarriage can lead to better psychological outcomes. Early Pregnancy Assessment Services (EPASs) are dedicated outpatient services considered the “gold standard” for miscarriage care. Little is known about the psychosocial support EPASs provide in Australia.AimsThe aim of this study was to explore the provision of psychosocial support in Australian EPASs.MethodsSemi-structured interviews were conducted with 29 purposively sampled key-informants from 13 EPASs. Interviews were audio-recorded, transcribed, and thematically analysed.FindingsConsiderable variation was found in how EPASs functioned and their provision of psychosocial support. Many services were co-located with antenatal services, run by doctors with limited experience and most did not offer any psychosocial training to staff specific to EPAS. Referrals for additional support were generally not offered for first trimester miscarriages, and follow-up typically focused on physical management rather than emotional wellbeing. All EPAS staff demonstrated a strong commitment to providing best possible care to women within their own clinical setting and acknowledged the need for improved psychosocial support.ConclusionThis study provides the first exploration of Australian EPASs’ provision of psychosocial support. It has shown that while health care professionals working in EPASs are dedicated to providing the best possible care to women within their clinical setting, psychosocial support is very limited and could be improved.  相似文献   
36.
The evaluation of hazards from complex, large scale, technologically advanced systems often requires the construction of computer implemented mathematical models. These models are used to evaluate the safety of the systems and to evaluate the consequences of modifications to the systems. These evaluations, however, are normally surrounded by significant uncertainties related to the uncertainty inherent in natural phenomena such as the weather and those related to uncertainties in the parameters and models used in the evaluation.

Another use of these models is to evaluate strategies for improving information used in the modeling process itself. While sensitivity analysis is useful in defining variables in the model that are important, uncertainty analysis provides a tool for assessing the importance of uncertainty about these variables. A third complementary technique, is decision analysis. It provides a methodology for explicitly evaluating and ranking potential improvements to the model. Its use in the development of information gathering strategies for a nuclear waste repository are discussed in this paper.  相似文献   
37.
As the civil law expression of internet plus transactions, the legal relations in online trading platform transactions constitute a complex aggregate of legal relationships composed of groups of legal relations. Specifically, they consist of three basic interlinked legal relationships: Contract relations for online trading platform services between the platform provider and the seller or service provider, and between the platform provider and the consumer. This includes the sales or service contract relations between the triad of the seller, the service provider and the consumer. These relations contain five kinds of major content, viz., the provision of transaction space, the publishing of transaction information, price escrow payment, distribution and delivery of the commodity, and transaction credit evaluation. They involve three forms of supplementary legal relations: the supplementary contract relationship between the platform provider and a third party payment institution; between the seller and third party credit reporting agency; and between the seller and a logistics enterprise. The three forms of supplementary contractual legal relations are set up to act on the major contents of the basic legal relationships in online transactions. On the basis of the online trading platform service contract relationships between the platform provider and the triad of the seller, the service provider and the consumer, the flow of the above- mentioned legal relations centers on the contract of sales or service set up between the seller, the service provider and the consumer to accomplish the aim of the online transaction, meet social needs and boost economic development.  相似文献   
38.
The objective of this article is to discuss a needed paradigm shift in disaster risk analysis to emphasize the role of the workforce in managing the recovery of interdependent infrastructure and economic systems. Much of the work that has been done on disaster risk analysis has focused primarily on preparedness and recovery strategies for disrupted infrastructure systems. The reliability of systems such as transportation, electric power, and telecommunications is crucial in sustaining business processes, supply chains, and regional livelihoods, as well as ensuring the availability of vital services in the aftermath of disasters. There has been a growing momentum in recognizing workforce criticality in the aftermath of disasters; nevertheless, significant gaps still remain in modeling, assessing, and managing workforce disruptions and their associated ripple effects to other interdependent systems. The workforce plays a pivotal role in ensuring that a disrupted region continues to function and subsequently recover from the adverse effects of disasters. With this in mind, this article presents a review of recent studies that have underscored the criticality of workforce sectors in formulating synergistic preparedness and recovery policies for interdependent infrastructure and regional economic systems.  相似文献   
39.
环境对量子控制系统的消相干揭示了一个事实,即量子世界里的系统将是一种全新的系统,它是某种开放的、数学的、并且是基于量子逻辑的系统。笔者认为,假如仍然还是立足经典思维,则系统的独立性将难以得到保证,传统的整体论也将变得自相矛盾。只有发展全新的"量子整体论",并在这种新的框架下去审视和建构量子系统,我们才有可能重新获得某种连贯一致的整体论。  相似文献   
40.
Louis Anthony Cox  Jr. 《Risk analysis》2012,32(11):1919-1934
Extreme and catastrophic events pose challenges for normative models of risk management decision making. They invite development of new methods and principles to complement existing normative decision and risk analysis. Because such events are rare, it is difficult to learn about them from experience. They can prompt both too little concern before the fact, and too much after. Emotionally charged and vivid outcomes promote probability neglect and distort risk perceptions. Aversion to acting on uncertain probabilities saps precautionary action; moral hazard distorts incentives to take care; imperfect learning and social adaptation (e.g., herd‐following, group‐think) complicate forecasting and coordination of individual behaviors and undermine prediction, preparation, and insurance of catastrophic events. Such difficulties raise substantial challenges for normative decision theories prescribing how catastrophe risks should be managed. This article summarizes challenges for catastrophic hazards with uncertain or unpredictable frequencies and severities, hard‐to‐envision and incompletely described decision alternatives and consequences, and individual responses that influence each other. Conceptual models and examples clarify where and why new methods are needed to complement traditional normative decision theories for individuals and groups. For example, prospective and retrospective preferences for risk management alternatives may conflict; procedures for combining individual beliefs or preferences can produce collective decisions that no one favors; and individual choices or behaviors in preparing for possible disasters may have no equilibrium. Recent ideas for building “disaster‐resilient” communities can complement traditional normative decision theories, helping to meet the practical need for better ways to manage risks of extreme and catastrophic events.  相似文献   
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