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1.
杨天雨  周玉新 《物流科技》2021,(2):44-45,55
随着互联网的快速发展,我国的手机愈发成为一部掌上电脑,通过手机进行外卖订餐已经成为现代高校大学生的日常状态,外卖的物流配送大大改变了学生的生活饮食方式。但是高校周围的外卖物流配送也容易导致很多问题,影响大学生的生活。针对高校外卖的特殊性,文章以互联网下逐渐形成的O2O模式来研究高校外卖物流配送的现状与发展,并且针对存在的问题提出相关建议。  相似文献   
2.
We consider a general local‐stochastic volatility model and an investor with exponential utility. For a European‐style contingent claim, whose payoff may depend on either a traded or nontraded asset, we derive an explicit approximation for both the buyer's and seller's indifference prices. For European calls on a traded asset, we translate indifference prices into an explicit approximation of the buyer's and seller's implied volatility surfaces. For European claims on a nontraded asset, we establish rigorous error bounds for the indifference price approximation. Finally, we implement our indifference price and implied volatility approximations in two examples.  相似文献   
3.
This paper studies the expansion of an option price (with bounded Lipschitz payoff) in a stochastic volatility model including a local volatility component. The stochastic volatility is a square root process, which is widely used for modeling the behavior of the variance process (Heston model). The local volatility part is of general form, requiring only appropriate growth and boundedness assumptions. We rigorously establish tight error estimates of our expansions, using Malliavin calculus. The error analysis, which requires a careful treatment because of the lack of weak differentiability of the model, is interesting on its own. Moreover, in the particular case of call–put options, we also provide expansions of the Black–Scholes implied volatility that allow to obtain very simple formulas that are fast to compute compared to the Monte Carlo approach and maintain a very competitive accuracy.  相似文献   
4.
Irrigation water rights and their governance structures constitute the foundation of local water institutions and profoundly influence water resource allocations, irrigated agricultural productivity and other consumptive water uses in the arid climate zones. This article explores the regional structures of irrigation water rights and water governance and empirically analyses the priority effects of water rights on irrigated agriculture at the micro level in Idaho, an arid and semiarid state in the western United States. We integrate a unique data set of water rights and water supplies with agricultural features and environmental characteristics into our empirical analysis. Results indicate that seniority in water resources allocation has significant, positive effects on both the average crop revenue and crop water use efficiency. Local water rights structures differ significantly in seniority and water sources from region to region. In response to the heterogeneity in local water rights structures, the aforementioned effect of allocative priority of water rights on average crop revenue per hectare and crop water productivity varies significantly, reaching up to an 87% difference, when measured across regions. In addition, the priority effects of water rights are nonlinear, which reflects the influence of historical patterns of water rights establishment on water institutions to date.  相似文献   
5.
本文从人口流动的区位黏性这一全新视角,将地方政府性债务的李嘉图等价命题纳入新经济地理研究框架进行理论分析。为了进一步揭示理论模型的政策含义,采用空间计量方法验证沿海地区地方政府性债务的局部正相关特征。最优的债务政策取决于经济系统的初始条件,在非对称经济结构已经存在的情况下,单纯建设本地区的基础设施只会降低区域内的交易成本,这对于那些仅着眼于投巨资用于城市“硬件”建设的地方政府来说显然是一叶障目。建议依靠基础设施网络提高区域协同创新能力,培育规模报酬递增的专业化产业集群。  相似文献   
6.
Aims: To estimate the cost to hospitals of materials (i.e. medications, equipment, and supplies) required to administer common interventions for post-surgical analgesia after total knee arthroplasty (TKA), including single-injection peripheral nerve block (sPNB), continuous peripheral nerve block (cPNB), periarticular infiltration of multi-drug cocktails, continuous epidural analgesia, intravenous patient-controlled analgesia (IV PCA), and local infiltration of bupivacaine liposome injectable suspension (BLIS).

Materials and methods: This analysis was conducted using a mixed methods approach combining published literature, publicly available data sources, and administrative data, to first identify the materials required to administer these interventions, and then estimate the cost to the hospital of those materials. Medication costs were estimated primarily using the Wholesale Acquisition Costs (WAC), the cost of reusable equipment was obtained from published sources, and costs for disposable supplies were obtained from the US Government Services Administration (GSA) database. Where uncertainty existed about the technique used when administering these interventions, costs were calculated for multiple scenarios reflecting different assumptions.

Results: The total cost of materials (i.e. medications, equipment, and supplies) required to provide post-surgical analgesia was $41.88 for sPNB with bupivacaine; $756.57 for cFNB with ropivacaine; $16.38 for periarticular infiltration with bupivacaine, morphine, methylprednisolone, and cefuroxime; $453.84 for continuous epidural analgesia with fentanyl and ropivacaine; $178.94 for IV PCA with morphine; and $319.00 for BLIS.

Limitations: This analysis did not consider the cost of healthcare providers required to administer these interventions. In addition, this analysis focused on the cost of materials and, therefore, did not consider aspects of relative efficacy or safety, or how the choice of intervention for post-surgical analgesia might impact outcomes such as length of stay, re-admissions, discharge status, adverse events, or total hospitalization costs.

Conclusions: This study provided an estimate of the costs to hospitals for materials required to administer commonly used interventions for post-surgical analgesia after TKA.  相似文献   
7.
Joint production of knowledge (JPK) is said to facilitate proactive mitigation of risks in marine resource management. However, lack of consensus on who should be involved, when it is happening and the exact mechanisms of sharing knowledge has precluded the development of an effective implementation framework. Here, we explore one approach to building a post-normal science, one that both includes local ecological knowledge and bridges scientific silos. We first identify several actions of knowledge production and then provide an Atlantic Canadian case study, drawn from an assessment of the impact of aquaculture on American lobster, to illustrate necessary actions on the road to JPK. Key actions include theorizing relationships, agreeing on key concepts, specifying, and interpreting required data, identifying principles and making evaluations. We fill a lacuna in the JPK literature by: first, defining knowledge as the result of a set of actions; second, using knowledge generating actions to explore how different knowledge sets come together to contribute to JPK; and third, identifying how knowledge actions can facilitate or inhibit JPK. We conclude that this list of the essential actions of knowledge production is necessary to the successful development of alternative approaches to risk.  相似文献   
8.
China’s reform on central–local fiscal reform has slowed down in recent years. The appointment of a new finance minister experienced in local government affairs is expected to renew the reform affirmed by the Chinese Communist Party (CCP) congress in late 2017. China has unprecedentedly identified a comprehensive list of 81 national basic public services as entitlements. Eighteen of them are subject to national and local standards, and co-financed by central and local governments. A new cost-sharing method for 10 of these services classifies sub-national jurisdictions into five tiers, in which the central government’s share declines from 80% to 10%. These measures, effective in 2019, aim at creating a ‘harmonious and moderately prosperous society’.  相似文献   
9.
This study explores the cost-reduction effects of local government consolidation, using data from Japanese municipalities. We use municipal panel data from Japan for the years 2000, 2005 and 2010, a data set including numerous consolidation cases. Reverse causality between consolidation decisions and size of municipal expenditure is a concern in the voluntary consolidation of local governments. An instrumental variable (IV) methodology is employed to deal with possible endogeneity associated with consolidation decisions. The main finding is that municipal current expenditure per capita increases immediately after consolidation, but then gradually declines. Because consolidation seems to increase per capita expenditure in the absence of the effect of this long-term declining trend, incorporating this trend into estimation is crucial in cost-efficiency analysis of consolidation. It is also shown that conventional panel data regressions yield biased consolidation effects, suggesting the superiority of the IV approach.  相似文献   
10.
[目的]进一步揭示土地财政已存在的区域差异规律,为构建更为科学、切实可行的政策建议,推动"征地→批租"地方政府土地财政模式转型提供新的研究视角。[方法]文献资料方法和比较研究方法。[结果]现有研究证实了土地财政规模及依赖程度、财政收入激励下地方政府土地出让方式、土地财政推动经济增长、土地财政影响居民收入消费及公共品供给、土地财政与城市用地规模联动关系等方面,在全国范围内都存在东部、中部、西部的区域差异。国外保有环节的房地产税是地方政府持续的财政资金来源;同时,是促进房地产市场有序发展、抑制城市蔓延的有效政策工具。[结论]未来研究方向是以地市为单元,探明各类土地财政构成要素对于经济增长、居民收入与消费及产业服务化、城市公共品供给、城市各类用地规模增长的影响内在机理;构建区域差别化的保有环节房地产税征收管理政策方案。  相似文献   
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