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1.
基于严寒区京沈客专朝阳试验段路基基床的温度监测资料分析,研究不同厚度聚氨酯保温板对高速铁路路基混凝土基床温度变化特性影响.测试结果表明:①铺设聚氨酯保温板能够有效阻断严寒区环境与路基基床间的热量传递,保温效果与板厚相关;②地温大多数时间呈阳高阴低现象,同时阴、阳坡路基温差波动幅度随埋深逐渐减小;③基床表层阴、阳面各测点的温度变化起始时间一致,而阴面的冻结时间比阳面晚一个月.由此表明,保温板能够有效降低环境与混凝土道床之间的热交换,但是对路基阴、阳坡的影响存在差异.建议在严寒地区高速铁路路基阳、阴坡可以采取不同厚度的聚氨酯保温板,减小阴阳坡地温差异,保持季冻土路基温度变化稳定. 相似文献
2.
Bouncing Back from Extreme Weather Events: Some Preliminary Findings on Resilience Barriers Facing Small and Medium‐Sized Enterprises
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George Halkos Antonis Skouloudis Chrisovaladis Malesios Konstantinos Evangelinos 《Business Strategy and the Environment》2018,27(4):547-559
Extreme weather events (EWEs) pose unprecedented threats to modern societies and represent a much‐debated issue strongly interlinked with current development policies. Small and medium‐sized enterprises (SMEs), which constitute a driving force of economic growth, employment and total value added, remain highly vulnerable to and ill prepared for such environmental perturbations. This study investigates barriers to SMEs’ resilience to EWEs in an attempt to shed light on enabling factors that can define effective organizational responses to non‐linear environmental stimuli. Relying on structural equation modeling and data gathered from 109 SMEs that recently experienced EWE impacts, we link the general concept of SMEs’ resilience barriers to EWEs with a series of elements to determine specific internal and external factors that contribute the most to EWE resilience. In particular, external barriers of institutional conditions and mechanisms of support and guidance as well as internal barriers of resources and managerial perceptions are found to be the most critical ones in determining resilience. The assessment offers essential research evidence for practitioners on SME management and sets forth linkages with current mechanisms for policy interventions towards an appropriate resilience agenda for SMEs. Copyright © 2018 John Wiley & Sons, Ltd and ERP Environment 相似文献
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4.
Simon P. Anderson
ystein Foros Hans Jarle Kind 《Journal of Economics & Management Strategy》2019,28(1):125-137
Consumer “multihoming” (watching two TV channels, or buying two news magazines) has surprisingly important effects on market equilibrium and performance in (two‐sided) media markets. We show this by introducing consumer multihoming and advertising finance into the classic circle model of product differentiation. When consumers multihome (attend more than one platform), media platforms can charge only incremental value prices to advertisers. Entry or merger leaves consumer prices unchanged under consumer multihoming, but leaves advertiser prices unchanged under single‐homing: Multihoming flips the side of the market on which platforms compete. In contrast to standard circle results, equilibrium product variety can be insufficient under multihoming. 相似文献
5.
Environmental Policy,Sustainable Development,Governance Mechanisms and Environmental Performance
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We investigate the effects of environmental policy (Climate Change Act – CCA), sustainable development frameworks (Global Reporting Initiative – GRI; UN Global Compact – UNGC) and corporate governance (CG) mechanisms on environmental performance (carbon reduction initiatives – CRIs; actual carbon performance – GHG emissions) of UK listed firms. We use the generalized method of moments (GMM) estimation technique to analyse data consisting of 2245 UK firm‐year observations over the 2002–2014 period. First, we find that the CCA has a positive effect on CRIs, and this effect is stronger in better‐governed firms. Second, we find that the GRI‐based framework is positively associated with CRIs. Third, we find that firms with poor CG structures have lower actual carbon performance compared with their better‐governed counterparts. Overall, our evidence suggests that firms can symbolically conform to environmental policy (CCA) and sustainable development frameworks (GRI, UNGC) by engaging in CRIs without necessarily improving actual environmental performance (GHG emissions) substantively. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment 相似文献
6.
OLESYA GRISHCHENKO SARAH MOUABBI JEAN‐PAUL RENNE 《Journal of Money, Credit and Banking》2019,51(5):1053-1096
We use several U.S. and euro‐area surveys of professional forecasters to estimate a dynamic factor model of inflation featuring time‐varying uncertainty. We obtain survey‐consistent distributions of future inflation at any horizon, both in the U.S. and the euro area. Equipped with this model, we propose a novel measure of the anchoring of inflation expectations that accounts for inflation uncertainty. Our results suggest that following the Great Recession, inflation anchoring improved in the United States, while mild de‐anchoring occurred in the euro area. As of our sample end, both areas appear to be almost equally anchored. 相似文献
7.
ABSTRACTThe aviation e-service system is an important part of support for business communication in regions covered by Belt and Road initiative. In exploring the role of airline companies in this system, we examine the structure of the network, which consists of airlines interconnections based on small data of individual attributes of aviation companies in aviation e-services, and study these interconnections across different groups using block modeling. The heuristic solution of airline companies in development of international communication and cooperation is further discussed. Among our policy implications for global managers, we suggest the enhancement of cross-regional cooperation among airlines. 相似文献
8.
冯儒梅 《中小企业管理与科技》2021,(9)
随着我国电网逐渐向智能电网迈进,信息技术在电能传输、转换、分配、调度等方面的应用,使电力企业可以进行结构调整,提高电力系统管理水平。据统计,2011年,我国电力信息化投资达220亿元,2012-2015年,电力工程建设稳步推进。为了促进电力企业全面开展项目成本核算和有效控制,提高电力工程项目的效益,确定了典型方案设计模块,通过定额规则库与典型方案设计相匹配的方法,解决了安装过程中定额第一版遗留的一些问题,并通过设计选型等措施加强了成本控制。 相似文献
9.
为检查工程质量,查找输水系统可能存在的问题并消除隐患,保障电站安全运行,福建仙游抽水蓄能电站在投产发电前,要对输水发电系统进行充水试验与放空排水试验,在试验过程中监测输水系统的应力、应变与渗漏水情况。本文以尾水系统为例,介绍了试验所应具备的工程条件、工作程序及技术要求、试验成果分析和存在问题处理等。试验表明,仙游抽水蓄能电站尾水系统设计合理,施工质量优良,结构可靠,可供同类工程参考与借鉴。 相似文献
10.
方芳 《中小企业管理与科技》2021,(7)
成本管理是预算管理和绩效管理的前提,企业需要正确地将成本进行分类、计量和归集。恰当的成本管理制度可以帮助企业提升运营效率和业务绩效,同时企业的流程改善、突破和优化与成本管理密不可分。另外,管理者需要令客户对产品和服务满意,并且有效控制各项成本。企业成本管理不是单纯地降低成本,而是通过利用成本分析工具,有效地管理和规划资源,进而提高总体运营效率,保证企业总体绩效的持续改善。论文通过成本计算制度的制定方法和业务流程改善分析技术两方面对成本管控进行探讨。 相似文献