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1.
为了研究骨料形态对再生混凝土材料力学性能的影响,基于势能原理的基面力元法,利用图像处理技术和MATLAB软件,建立了再生混凝土真实骨料细观模型。应用FORTRAN分析软件对再生混凝土试件进行单轴拉伸试验的数值模拟,研究了真实骨料细观模型再生混凝土宏观应力-应变曲线变化规律和试件的破坏形态。结果显示,真实骨料模型得到的宏观应力-应变曲线和试验曲线吻合度较高,骨料形状对试件的破坏形态影响较小。模型可真实地模拟再生混凝土在单轴拉伸作用下的损伤破坏过程,准确地反映试件的实际骨料形态。  相似文献   
2.
This paper examines the effects of disclosing greenhouse gas (GHG) information mandatorily on the cost of equity capital (COC) using a longitudinal unbalanced panel database of the United Kingdom's FTSE 350 firms for the period 2011–2016. We use a nonlinear panel quantile regression (PQR) model to examine the relationship between GHG disclosure (GHGD) and COC in the United Kingdom. This technique was supplemented by conducting a two-step generalised method of moment (GMM) estimation to address any concerns related to the potential existence of endogeneity problems. Our findings suggest that high-level GHGD appeared to be negatively associated with COC up to a certain level, which is known as the turning point; then, any increase in GHGD is likely to increase the COC. This means that the nonlinear association between GHGD and COC is evidenced in our study and takes a U shape. Likewise, our findings are associative of a moderating effect of the 2013 carbon disclosure regulation (CDR) on the GHGD–COC nexus. We argue that mandatory GHGD and GHG risk are linked so that those companies that are associated with higher GHG risk have a tendency to be better disclosers. Consequently, we urge regulators to design GHGD regulations in a way that mirrors corporate environmental risk and leads to a lower COC in order to align the interests of corporations with those of the society at large.  相似文献   
3.
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   
4.
提出行业性风险暴发的"腐蚀效应"理论,即存在着一种特殊的行业风险暴发过程:行业中各个企业的倒闭是沿着企业的资质链从低到高的顺序发生的.该过程的存在得到了数据回归证实.对于科技金融等新兴行业,警惕和积极防范腐蚀效应,对防范行业性风险具有重要意义.对于客户信任高度依赖的新兴行业,如金融科技等,最容易出现腐蚀效应.因此,在一度高速膨胀的网络贷款领域出现腐蚀效应具有一定必然性."腐蚀效应"的存在也否定了当前把网络贷款行业大面积爆雷的原因归咎于其开展"增信服务"的普遍观点,真正引发风险的原因是网络贷款行业中的企业资质参差不齐和无序竞争造成的无谓成本的大幅增加.从政府对行业的管理视角来看,在促进行业发展时不忘记防范风险十分重要.这在实质上是对制度-制度接口的设计问题.因此应当以制度设计理论来指导防范风险政策的制定,才能取得更好的效果.  相似文献   
5.
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   
6.
How are novel organizations able to build a positive reputation while attempting to enter into a system with established organizations? To address this, we examined the field of elite‐level amateur hockey. Private Secondary Schools (PSS) are novel in that they offer a nontraditional pathway for players with respect to fielding elite‐level hockey teams. Findings from interviews with PSS with elite‐level hockey programs revealed that PSS highlight their Selection Processes, Player Development Practices, and the enhanced Player Experience in an effort to build a positive reputation. This study contributes to the literature on reputation by showing that novel organizations can build a reputation through highlighting the unique value they add. Copyright © 2016 ASAC. Published by John Wiley & Sons, Ltd.  相似文献   
7.
This study back-tests a marginal cost of production model proposed to value the digital currency Bitcoin. Results from both conventional regression and vector autoregression (VAR) models show that the marginal cost of production plays an important role in explaining Bitcoin prices, challenging recent allegations that Bitcoins are essentially worthless. Even with markets pricing Bitcoin in the thousands of dollars each, the valuation model seems robust. The data show that a price bubble that began in the Fall of 2017 resolved itself in early 2018, converging with the marginal cost model. This suggests that while bubbles may appear in the Bitcoin market, prices will tend to this bound and not collapse to zero.  相似文献   
8.
This paper is amongst the first to examine coopetition strategy for sustainable development at the network level. Companies who want to successfully implement complex innovative technologies that support sustainable development need to collaborate with other actors of the innovation ecosystem, including their competitors, so that they can develop standards, interoperable products, pool knowledge, and resources and bundle forces to compete against other technologies. Collaboration with competitors brings benefits, but also many risks. We investigated how firms cope with these risks when establishing an innovation ecosystem to implement a new technology in society. We conducted research in the Dutch smart grids sector and explored how these firms minimize inherent risks of coopetition. We found that system‐building actors in the Dutch smart grid field not only minimize inherent risks, but from the start of their collaboration they implement so‐called enablers to prevent these risks upfront.  相似文献   
9.
Aims: The EINSTEIN-Extension trial (EINSTEIN-EXT) found that continued treatment with rivaroxaban for an additional 6 or 12 months (vs placebo) after 6–12 months of initial anticoagulation significantly reduced the risk of recurrent venous thromboembolism (VTE) with a small non-significant increased risk of major bleeding (none fatal or in critical site). This study aimed to compare total healthcare cost between rivaroxaban and placebo, based on the EINSTEIN-EXT event rates.

Methods: Total healthcare cost was calculated as the sum of treatment and clinical event costs from a US managed care perspective. Treatment duration and event rates were obtained from the EINSTEIN-EXT study. Adjustment on treatment duration was made by assuming a 10% non-adherence rate. Drug costs were based on wholesale acquisition costs. Cost estimates for clinical events (i.e. recurrent deep vein thrombosis [DVT], recurrent pulmonary embolism, major bleeding, clinically relevant non-major bleeding) were determined from the literature. Results were examined over a ±20% range of each cost component and over 95% confidence intervals (CIs) of event rate differences in deterministic (one-way) and probabilistic sensitivity analyses (PSA).

Results: Total healthcare cost was $1,454 lower for rivaroxaban-treated (vs placebo-treated) patients in the base-case, with a lower clinical event cost fully offsetting drug cost. The cost savings of recurrent DVT alone (–$3,102) was greater than drug cost ($2,723). Total healthcare cost remained lower for rivaroxaban in the majority (73%) of PSA (cost difference [95% CI]?=?–$1,454 [–$2,396, $1,231]).

Limitations: This study was conducted over the 1-year observation period of the EINSTEIN-EXT trial, which limited “real-world” applicability and examination of long-term economic impact. Assumptions on drug and clinical event costs were US-based and, thus, not applicable to other healthcare systems.

Conclusions: Total healthcare costs were estimated to be lower for patients continuing rivaroxaban therapy compared to those receiving placebo in VTE patients who had completed 6–12 months of VTE treatment.  相似文献   
10.
《The World Economy》2018,41(6):1664-1694
This paper studies the consequences of parallel trade in a two‐country model. It compares a coinsurance scheme (consumers pay a percentage of the drug price) and an indemnity insurance scheme (reimbursement is independent of the drug price) with respect to changes in copayments and public health expenditure. In the destination country, copayments for patients decrease to a larger extent under indemnity insurance, whereas reductions in public health expenditure occur only under coinsurance. In the source country, copayments increase less under coinsurance, whereas health expenditure is reduced more under indemnity insurance. In both countries, total expenditure under parallel trade is lower.  相似文献   
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