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1.
马小龙  谷宇 《科技和产业》2023,23(14):147-151
小农户与现代农业发展的有机衔接是当前实施乡村振兴战略的关键措施,农业生产托管正是实现小农户与现代农业有机衔接的最有效途径。探究农业生产托管中组织关系的演化及动力机制可以对农业生产托管有更清晰的认识,更好地推进农业生产托管,为进一步规范农业生产托管提出对策建议。  相似文献   
2.
We apply dynamic data envelopment analysis (DEA) to estimate dynamic cost inefficiency for a sample of European Union (EU) large meat processing firms over the period 2005–2012 and decompose this into the contributions of technical and allocative inefficiency. The estimation of dynamic inefficiencies controls for adjustment costs associated with firms’ investments. We further contribute by measuring dynamic cost inefficiencies and their components with regard to own region group (managerial inefficiencies) and the gap between the pooled frontier and the region-specific frontier (programme inefficiencies). Results show that technical inefficiency tends to be the largest component of cost inefficiency when both conducting the analysis for the EU as a whole and estimating a region-specific frontier. Results suggest significant differences in cost, technical, and allocative inefficiencies between meat processing firms in eastern, western and southern EU countries. We also find that the gaps between the pooled and region-specific frontiers tend to be small to negligible, which suggests that the main source of pooled inefficiencies are shortcomings in managerial practices rather than differences in region-specific conditions.  相似文献   
3.
In mergers and acquisitions, the acquiring firm must combine two firms’ resources and capabilities so that the outcome yields value. In individual firms, the marketing & sales, and R&D functions have typically developed intertwined and complex relationships over time. These multifaceted dependencies may obscure the integration of the firms and their functions. In order to reveal to what extent cross-functional relationships determine the success or failure of an acquisitions, we have made one of the first attempts to study merging firms’ function-specific capabilities, underlying microfoundations, and their cross-functional relationships during the integration process—instead of focusing on acquisition capabilities as such. We use longitudinal data from two cross-border acquisitions between US and Finnish SMEs. Our results indicate that major differences between merging firms’ cross-functional microfoundations—that is, their structures, processes, routines, and skills—might either enforce or erode the seemingly promising synergies at the product and market levels, depending on managerial awareness of their nature.  相似文献   
4.
本文在一个三阶段动态博弈框架下,对政府随机审计过程中的政府审计机关与政府审计对象以及国家与政府审计对象之间的动态博弈特征进行了分析。分析结果显示:政府审计机关与政府审计对象之间存在一个纯策略纳什均衡,而国家和政府审计对象之间存在一个混合策略纳什均衡。政府审计对象接受国家实质性审计的概率是政府审计对象被政府机关审计发现违规或不作为后的惩罚倍数的单调递减函数,而政府审计对象的违规或不作为的概率分别是政府审计对象被政府机关审计发现违规或不作为后的惩罚倍数和政府审计对象的应尽义务或责任的单调递减函数,却是政府审计机关审计行为成本的单调递增函数。同时,结合研究结论和中国政府审计全覆盖的现实,给出了一些政策建议。  相似文献   
5.
I study points programs, such as frequent flyer and other rewards programs, as a revenue management tool. I develop a two‐period contracting model where a capacity‐constrained firm faces consumers who privately learn their valuations over time. The firm cannot commit to long‐term contracts, but it can commit to allocate any unsold capacity through a points program. This points scheme creates an endogenous and type‐dependent outside option for consumers, which generates novel incentives in the firm's pricing problem. It induces the firm to screen less ex interim, and to offer lower equilibrium prices, reversing the intuition of demand cannibalization.  相似文献   
6.
We price an American floating strike lookback option under the Black–Scholes model with a hypothetic static hedging portfolio (HSHP) composed of nontradable European options. Our approach is more efficient than the tree methods because recalculating the option prices is much quicker. Applying put–call duality to an HSHP yields a tradable semistatic hedging portfolio (SSHP). Numerical results indicate that an SSHP has better hedging performance than a delta-hedged portfolio. Finally, we investigate the model risk for SSHP under a stochastic volatility assumption and find that the model risk is related to the correlation between asset price and volatility.  相似文献   
7.
Natural resources influence economic performance through many different mechanisms, both beneficial and harmful. Some of these mechanisms tend to set in fast while others are rather slow. This suggests that pooling the long- and short-run effect as typical in the resource empirical literature may lead to incorrect inferences. This article provides an evaluation of the income contribution of natural resources using a panel cointegration approach that allows for short-run dynamic heterogeneity while imposing the restriction of long-run homogeneity. It finds, in a sample of developing countries over the period 1990–2012, that natural resources are a curse in the long run. The evidence is robust to alternative dynamic specifications, different measures and types of natural resource wealth, and controlling for regional effects.  相似文献   
8.
ABSTRACT

This study takes a micro standpoint to quantitatively verify the extent to which local interactions affect the expansion of dynamic social networks. By reviewing and synthesizing the theoretical literature in this article, we seek to establish a pragmatic analytical framework to capture the underlying functioning of local interactions. It then aims to produce findings on seven distinct marketing campaigns in which the real-world virtual communities offer intact time-series connections. In our considered cases, the firm-to-consumer interactivity plays a pivotal role in social media marketing while the customer-driven influence advances individual information transmission. The significant positive relationships demonstrate features of interactivity within subgroups including reciprocal edges and directed 3-cliques associated with the evolution of the virtual community by electronic word-of-mouth (WOM) of both firm-to-consumer and consumer-to-consumer interactions. More importantly, the attenuation of local interactions to a large extent leads to the cut-off point of the growth of the dynamic social network.  相似文献   
9.
为了加快低密度奇偶校验(LDPC)码的译码速度,有效改善LDPC码的译码性能,针对校验节点更新过程中的对数似然比(LLR)值的大小,设计了一种LDPC码的动态加权译码方法。以IEEE 802.16e标准的奇偶校验矩阵为例,根据LLR值的变化规律,利用增长因子和抑制因子对和积译码算法和最小和译码算法进行动态加权。仿真结果显示,基于动态加权的译码方法相对于传统译码方法误码率都有明显改进,译码复杂度也有所降低。  相似文献   
10.
The effect of different supplementary feeding rates for grazing cattle on high-altitude pastures dynamics was evaluated. A field experiment was carried out during three years in a subalpine pasture area of the Eastern Alps. The investigated pasture area was 40?ha, located between 1820 and 2230?m?a.s.l. Two paddocks were chosen in the experiment and two herds of 12 cattle each were kept in the two enclosures for 5 weeks. For the first herd (HS), the supplementary feeding rate was 4.8?kg?OM?head?1 per day, while for the second herd (LS), the rate was 1.6?kg?OM?head?1 per day. The amount of herbage consumed by each cattle was determined using the n-alkane technique. To monitor the pasture vegetation dynamics, eight metal exclusion cages were placed in each paddock to determine herbage growth, utilization rates, vegetation composition and animal grazing selectivity. Grazing behaviour of dairy cattle, in terms of herbage intake and species selection was affected by the different feeding rates. Cattle grazing Paddock HS consumed 1.9?kg?OM?day?1 of herbage less than Paddock LS. In the LS paddock, cattle grazed higher phytomass rates. When the animals were fed by higher concentrate rates, a more selective grazing seemed to significantly increase the pasture necromass component. The lower grazing selectivity favoured the development of species as Nardus stricta and Deschampsia caespitosa, which are well known for their low palatability. Distinct vegetation dynamic patterns were observed, with a reduction of hair grass and an increase of legumes in the Paddock LS.  相似文献   
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