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11.
曹文 《价值工程》2021,40(3):155-157
针对富水砂层盾构接收易发生渗漏、涌砂、安全风险大等问题。在大量工程实践基础上,总结出以控制地下水为重点、坚持预防为主的施工理念,形成端头加固、止水帷幕、环箍注浆及止水装置的富水地层盾构接收技术,牢筑三道止水防线。技术成果在多项依托工程中成功应用,确保了该类地层盾构接收安全和风险可控。  相似文献   
12.
从效率差异视角构建国家创新影响力评价方法,揭示“一带一路”沿线国家创新要素流动倾向性以促进交流合作。运用DEA模型测算各国创新效率,根据DEA原理识别国家间的认可关系,构建创新网络并用节点特征向量中心度表示各国创新影响力,分析创新影响力类型、创新网络特征及创新投入冗余率与产出不足率。结果发现,各国创新效率存在显著差距;各国分别处于创新网络中心、核心和边缘位置,国家创新影响力依次递减;按照创新要素相对强度,沿线国家可分为6种创新类型;最后,提出沿线国家间开展创新交流与合作的必要性和途径。  相似文献   
13.
Upgrading in global value chains (GVCs) is an important path for developing countries to move along to capture higher benefits. Several qualitative studies of GVCs have identified two main upgrading types: economic (product, process, functional, and inter-sectoral) and social upgrading. The upgrading concept is widespread in productive sectors such as processed food, which has become a key export for developing countries. However, they have confronted multiple product standards required by global buyers. This study uses a case study of Thailand’s processed food exports (TPFEs). Although Thailand is a leading exporter of processed food, the country needs to upgrade in many areas related to production to meet global product standards and requirements. If Thailand fails to comply with global product standards, it will lose its export competitiveness. This study uses a gravity model to evaluate the impact of economic and social upgrading (EUP and SUP) on TPFEs. Our results show that upgrading types are significant in TPFEs, particularly for exports to developed countries. Process upgrading has a negative impact on TPFEs because of increased production costs to comply with product standards. However, process upgrading can lead to increased producers’ and exporters’ knowledge about how to comply with international standards. Consequently, process upgrading exhibits a lagged positive effect on TPFEs.  相似文献   
14.
文章通过对黑龙江省高效节水现状,存在问题的分析,结合黑龙江省高效节水发展的支撑能力,阐述黑龙江省节水增粮目标、任务及总体布局,为黑龙江省2012—2015年节水增粮实施提供依据。  相似文献   
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In this article, we investigate the existence of long-run common trends between imports and remittances in 11 Central and Eastern European countries which are part of the European Union. Using the Engle–Granger two-step procedure, we determine that for all countries in our sample there are no long-run common trends (no cointegration) between imports and remittances. However, the results are mixed when running a Granger causality test. For nine countries, we can establish either a bidirectional or unidirectional Granger causality, indicating that past values of one variable have predictive content on the other variable. In two countries, there is no Granger causality between imports and remittances.  相似文献   
17.
Are poor macroeconomic outcomes primarily the result of economic policies, or of deeper underlying state fragility problems in sub‐Saharan Africa? We attempt to answer this question by using carefully specified dynamic panel regression techniques to show how state fragility conditions help to explain the differences in the macroeconomic performance of sub‐Saharan African economies, and to identify the most plausible mechanisms of transmission. We find that countries with greater fragility suffer higher macroeconomic volatility and crisis; they also experience weaker growth. When we disaggregate state fragility into its various components, we find that it is the security and social components that have the strongest causal impact on macroeconomic outcomes, while the political component is, at best, weak. Therefore, we conclude that it is state fragility conditions, and not necessarily macroeconomic policies, that are of first‐order importance in explaining the differences in macroeconomic performance for African countries. The knock‐on effects are mostly mediated through the fiscal channel, the aid channel, and the finance channel. Accordingly, we recommend that interventions in fragile states should best focus on exploiting the potential for using fiscal policy, aid, and finance as instruments to improve macroeconomic outcomes in sub‐Saharan Africa.  相似文献   
18.
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   
19.
《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   
20.
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   
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