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31.
In recent decades, agricultural production in the U.S. has continued to shift to large-scale operations, raising concerns about the economic viability of small and midsized farms. To understand whether economies of size provided an incentive for the consolidation of production, the study estimates the total factor productivity (TFP) of five size classes of grain-producing farms in the U.S. Heartland (Corn Belt) region. Using quinquennial Agricultural Census data from 1982 to 2012 the study also compares TFP growth rates across farm sizes to gain insight into whether observed productivity differences are likely to persist. The finding of a strong positive relationship between farm size and TFP suggests that consolidation of production has contributed to recent aggregate productivity growth in the crop sector. The study estimates the extent to which sectoral productivity growth can be attributed to structural change versus other factors including technological change. The study also explores some tradeoffs associated with policies that raise the productivity of small versus large farms.  相似文献   
32.
Retailing strategy is one of the most crucial factors for industries. A proper retailing strategy can help to enhance consumer service and increase the industry's profit. An improved approach to retailing is suggested in this research to deliver superior customer service while maximizing profits in a dynamic system. The study analyzes a retailing strategy for a demand with cross-price elasticity upon the retail price. A product's cross-price elasticity and the system reliability are critical factors in retailing. Understanding the cross-price elasticity of demand between products helps retailers to make pricing decisions that maximize profits by maintaining demand. Imperfect products are produced due to an imperfect production system. The imperfect ones must be adjusted with some costs to make them perfect for better retailing. The system failure rate is crucial for retailing under cross-price elasticity of demand patterns. Production system reliability, cross-price elasticity of demand, and consumer service are all essential factors that can impact a company's success in the market. The production rate is considered time- and system failure rate-dependent. Contradictory to the literature, a dynamical system is proposed for improved retail management, which is solved using the Euler-Lagrange theory. Finally, one can achieve the expected maximum profit for this retail system with optimum selling prices for different products by reducing the system failure rate. Some numerical illustrations with graphical representations are provided to validate the current study. Numerical examples show that applying cross-price elasticity of demand for more than two identical products provides 35% more profit for the retail industry than a single type of product.  相似文献   
33.
Motivated by the European sovereign debt crisis, we propose a hybrid sovereign default model that combines an accessible part taking into account the evolution of the sovereign solvency and the impact of critical political events, and a totally inaccessible part for the idiosyncratic credit risk. We obtain closed‐form formulas for the probability that the default occurs at critical political dates in a Markovian setting. Moreover, we introduce a generalized density framework for the hybrid default time and deduce the compensator process of default. Finally, we apply the hybrid model and the generalized density to the valuation of sovereign bonds and explain the significant jumps in long‐term government bond yields during the sovereign crisis.  相似文献   
34.
Interest in supporting local and regional food systems is rising and food hubs have attracted considerable attention among Federal, State, and local policymakers. This study explores the problem of endogenous hub location in fresh produce value chains in the Northeastern United States. To overcome limitations in the literature, we incorporate the effects of economies of scale and production seasonality into our models. Three experimental models are designed to examine the effects of alternatively applying yearly, quarterly, and monthly data on model solutions. We explicitly assess how interactions of scale economies and seasonality influence the structure and spatial attributes of an optimal regional produce aggregation hub system. The three models generate marketed different solutions and in many respects they lead to different conclusions about developing local/regional supply chains. The monthly model allows for production seasonality and actual hub operation cycle frequency and thus leads to more efficient hub solution with rich policy implications.  相似文献   
35.
《Journal of Retailing》2019,95(4):111-115
Sensory elements are an important aspect of both offline and online retail stores and can non-consciously influence consumer judgments and purchase behavior. In offline settings, ambient factors like scent, lighting, and music have been shown to influence customers’ shopping experiences and their buying behaviors. For online retail outlets, sensory factors related to color, display patterns, and layouts can have significant effects on consumer behavior. Sensory elements have strong managerial relevance since they can non-consciously influence behaviors and because they are relatively easy to change; for example, it requires minimal effort to change the lighting or the music at a physical retail store or the display pattern for an online store. The eight papers in this special issue address theoretical and practical issues related to how different sensory elements can strongly influence retail practices. These papers focus on underexplored topic areas and also on emerging technologies, which stimulate thoughts for further research in these areas.  相似文献   
36.
田璐玚 《科技和产业》2023,23(13):175-182
智慧居家养老服务的协同供给可以形成社会联动效应,降低公共服务成本。运用公共服务协同供给分析框架,通过交叉分类方法从协同主体的利益与目标两个变量的耦合性出发分析广西钦州市智慧居家养老项目中养老服务主体间不同种类的协同关系,可以从加强政府领导、形成合作联盟、建立市场标准、创新扶持政策4个方面完善政府、企业、社会组织之间不同类型的协同供给,实现社会资源的高效利用以及向智慧居家养老服务的发展和转变。  相似文献   
37.
Artificial intelligence (AI) has captured substantial interest from a wide array of marketing scholars in recent years. Our research contributes to this emerging domain by examining AI technologies in marketing via a global lens. Specifically, our lens focuses on three levels of analysis: country, company, and consumer. Our country-level analysis emphasizes the heterogeneity in economic inequality across countries due to the considerable economic resources necessary for AI adoption. Our company-level analysis focuses on glocalization because while the hardware that underlies these technologies may be global in nature, their application necessitates adaptation to local cultures. Our consumer-level analysis examines consumer ethics and privacy concerns, as AI technologies often collect, store and process a cornucopia of personal data across our globe. Through the prism of these three lenses, we focus on two important dimensions of AI technologies in marketing: (1) human–machine interaction and (2) automated analysis of text, audio, images, and video. We then explore the interaction between these two key dimensions of AI across our three-part global lens to develop a set of research questions for future marketing scholarship in this increasingly important domain.  相似文献   
38.
This paper develops an approach to evaluating designs for digitalisation interventions in purchasing and supply management (PSM), and identifies some fundamental design principles for such interventions. A set of advanced technologies for digitalisation and a theory-based set of seven value drivers for PSM are identified for the proposed grid to facilitate the design of applications and interventions for digitalising PSM. The grid relates the digital technologies to the PSM value drivers in a matrix-like manner, allowing the structured consideration of the space defined by these two dimensions. The proposed approach to the strategic evolution of digitalisation in PSM is tested and its utility is demonstrated in analyses of practitioner literature and multiple case-study-based perspectives on PSM digitalisation. Two fundamental design principles relating to the use of the grid, or to the filling of its space, are set out, thus the research provides new theoretical perspectives on the design of advanced forms of PSM digitalisation. The proposed grid may be used in application design, communicating current and future states of PSM digitalisation to stakeholders, and specifically in developing a future-oriented strategy with a digitalization element for the PSM function.  相似文献   
39.
为解决实际应用中克拉维酸钾峰与后相邻杂质的分离度达不到要求的问题,建立了一种同时测定阿莫西林克拉维酸钾片中阿莫西林和克拉维酸钾含量的新方法,采用反相高效液相色谱法(RP-HPLC),Ultimate AQ-C_(18)色谱柱(4.6mm×250 mm,5μm),以pH值为4.4的0.05 mol/L磷酸二氢钠缓冲液为流动相,柱温为35℃,流速为1.0mL/min,检测波长为220nm。结果表明:阿莫西林和克拉维酸钾两主峰与相邻杂质得到完全基线分离,分离度大于1.5;克拉维酸钾对照品溶液质量浓度为0.050 0~0.500 1mg/mL时与峰面积的线性关系良好(r=0.999 8),平均回收率(n=9)为100.14%,RSD值为0.24%;阿莫西林对照品溶液质量浓度为0.100 0~1.000 1mg/mL时与峰面积的线性关系良好(r=0.999 9),平均回收率(n=9)为100.45%,RSD值为0.17%。与原有的《中华人民共和国药典》方法相比,新的阿莫西林克拉维酸钾片含量测定方法专属性好,准确度高,操作简便快捷,结果可靠,可作为一种质量控制方法。  相似文献   
40.
刘艳 《科技和产业》2018,(11):49-52
Catapults(弹射中心)作为一种新型研发组织形式,在英国创新发展战略的实施中扮演着重要角色。精准的组织功能定位、高效的组织管理运作模式和紧密的网络化组织关系,是Catapults组织管理模式创新的重要三大重要内容。为我国新型研发机构的培育和发展提供了良好的参考样本。  相似文献   
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