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141.
于荣陈枫唐润 《河海大学学报(哲学社会科学版)》2018,20(6):42-49
农产品质量已经引起公众的广泛关注。考虑由一个供应商和一个零售商构成的两级农产品供应链,构建零售商主导下的Stackelberg分散决策博弈模型和两者协同合作下的集中决策博弈模型,以供应商和零售商的最优质量努力水平为状态变量,利用逆向求解法得出供应商和零售商的最优质量决策。研究表明:在一定条件下,农产品供应链中主体的合作可以实现供应商、零售商和整个供应链系统利润的Pareto改善,在此基础上分析实现Pareto改善的条件以推动农产品供应链达到协调。 相似文献
142.
进入模式是经济组织配置资源的重要手段。以工商资本对农户经营活动的控制权程度为依据,将工商资本投资农业的进入模式划分为“松散型”、“半紧密型”、“紧密型”三种类型。利用对广东、湖北、江苏以及云南四省151个投资主体的调查数据,采用有序逻辑回归模型分析生产因素、市场因素、制度因素以及生产技术传递能力对工商资本投资农业的进入模式选择的影响。结果表明:耕地资源优势越弱,工商资本投资农业选择紧密型进入模式的可能性越高;市场潜力越大,越倾向于选择紧密型进入模式;非正式制度越不利,选择紧密型进入模式的可能性越低;生产技术的传递能力越弱,越倾向于选择紧密型进入模式。 相似文献
143.
兰州市洒水治污政策变迁路径与动力研究——基于定性比较分析法 总被引:1,自引:0,他引:1
以兰州市洒水车治污政策为研究案例,应用清晰集定性比较分析法(Crisp-set QCA)研究地方政府具体环保政策的变迁问题。分析发现,自上而下的政治压力、公众舆论压力、媒介压力、专家压力以及领导变更等五类8个解释变量可以作为案例政策变迁的驱动因素,其中,中央媒介压力是政策变迁的必要条件。按照不同的驱动因素组合,兰州洒水治污政策变迁有4种演进路径,其中,最短路径是“中央媒介压力且网络媒介压力”与“领导批示且中央媒介压力”。此外,在本政策案例中,领导批示不但没有促成政策变迁,甚至不构成变迁的必要条件。无论是“地方领导留言板”,还是“门户网站留言板”均非政策变迁的充分或必要条件,因此未能彰显公民参与在政策问题建构中的权力扩大,公众并没有实质拥有建构权,也未能成为建构主体,仅依赖互动平台的构建是无法打破原有的政策问题建构秩序的,因而也不能促使政策变迁彰显民意。 相似文献
144.
《Women and birth : journal of the Australian College of Midwives》2021,34(6):e575-e583
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
145.
研究需求受价格和商誉共同影响下易逝品动态定价与广告投资策略的联合决策问题。在初始库存确定的情形下,在某待定销售周期内,企业通过投入广告提升自身商誉从而拓宽市场,以企业利润最大化为目标,建立联合最优动态定价及广告投资策略模型。应用庞特里亚金极大值原理,求得不同系统参数下最优动态定价和广告投资策略及最优的销售周期。通过数值算例验证方法的有效性,结合参数灵敏度分析检验系统参数对最优策略的影响并给出相应管理意义。 相似文献
146.
《Journal of Statistical Computation and Simulation》2012,82(1-4):175-196
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
147.
ABSTRACTIn the case of a disease spreading over a time-scale comparable to the average lifetime in a host population, when the infectiousness of individuals depends on the tine since the onset of infection and when infections involve both drug-sensitive and drug-resistant strains of a pathogen, resistance may develop during the treatment of drug-sensitive strains. If increasing the treatment rate reduces the reproduction number of the drug-sensitive strain to a value below the reproduction number of the drug-resistant strain, then the disease may persist at a boundary equilibrium where only drug-resistant infection is present. 相似文献
148.
The problem of constructing control charts for fuzzy data has been considered in literature. The proposed transformation approaches and direct fuzzy approaches have their advantages and disadvantages. The representative values charts based on transformation methods are often recommended in practical application. For representing a fuzzy set by a crisp value, the weight of importance of the members assigned with some membership levels in a fuzzy set should be considered, and the possibility theory can be employed to deal with such problem. In this article, we propose to employ the weighted possibilistic mean (WPM), weighted interval valued possibilistic mean (WIVPM) of fuzzy number as a sort of representative values for the fuzzy attribute data, and establish new fuzzy control charts with WPM and WIVPM. The performance of the charts is compared to the existing fuzzy charts with a fuzzy c-chart example via newly defined average number of inspection for variation of control state. 相似文献
149.
耿荃 《天津市财贸管理干部学院学报》2012,14(3):88-90
e7T中华财会网网络技术的发展对企业内部会计控制产生了深远的影响,文章从网络环境下内部会计控制呈现的新特点着手,分析了网络环境下内部会计控制系统所面临的风险,对存在的问题及其成因作了尝试性的探讨,提出了完善、加强内部会计控制的建议,以期达到提高网络环境下内部会计控制质量的目的。 相似文献
150.