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1.
杨楠 《价值工程》2021,40(15):47-48
基于工程项目管理沙盘实验和工程项目实施控制的相关理论,运用工程项目管理沙盘从施工方案与进度计划的制定,材料购买方式,施工队伍进出场安排以及融资方式选择等方面对世纪大桥工程进行实验模拟,并运用赢得值理论结合分析软件进行成本控制与优化,寻找影响工程项目实施控制的因素,从而得到最优方案.  相似文献   
2.
Aims: Depression is the most frequent comorbidity reported among patients with rheumatoid arthritis (RA). Comorbid depression negatively impacts RA patients’ health-related quality-of-life, physical function, mental function, mortality, and experience of pain and symptom severity. The objective of this study was to assess healthcare utilization, expenditures, and work productivity among patients with RA with or without depression.

Materials and methods: Data from adult patients who had at least two visits each related to RA and depression over a 1-year period were extracted from the Truven Health MarketScan research databases. Outcomes comprised healthcare resource utilization, work productivity loss, and direct healthcare costs comparing patients with RA with depression (n?=?3,478) vs patients with RA without depression (n?=?43,222).

Results: Patients with RA and depression had a significantly greater relative risk of hospitalization and number of all-cause and RA-related hospitalizations, utilization of emergency services, days spent in the hospital, physician visits, and RA-related surgeries compared with RA patients without depression. Patients with RA and depression had a higher risk of and experienced more events and days of short-term disability compared with patients without depression. The incremental adjusted annual all-cause and RA-related direct costs were $8,488 (95% CI = $6,793–$10,223) and $578 (95% CI = –$98–$1,243), respectively, when comparing patients with RA and depression vs RA only.

Limitations: The current analysis is subject to the known limitations of retrospective studies based on administrative claims data.

Conclusions: This study suggested increased healthcare utilization, work productivity loss, and economic burden among RA patients due to comorbid depression. These findings emphasize the importance of managing depression and including depression as a factor when devising treatment algorithms for patients with RA.  相似文献   
3.
周霞  王楠  毕添宇  陈震  季鹏 《城市发展研究》2021,28(6):中插1-中插7
国家级新区是国家区域空间生产策略的体现,新时期高质量发展对其空间优化提出新要求.基于产城融合、区域协同与双效提升的高质量发展目标体系,构建国家级新区空间优化效果—效率双评价四分图模型,比较分析浦东、滨海等6个国家级新区2011~2017年空间优化水平.研究发现:(1)6个国家级新区空间优化水平整体呈现马太效应,低效果—低效率的新区间差距呈扩大趋势.(2)国家级新区空间优化水平存在南高北低的区域差异,南部4个新区中,2010年前成立的新区空间优化水平更高.(3)国家级新区空间优化效果与效率总体均值呈现类雁形与"乀"形变化.从以动态评价赋能精准施策、以绿色创新推动产城融合、以开放协调带动新区合作、以双效提升引导差异化发展等方面提出国家级新区空间优化的建议.  相似文献   
4.
We examine risk profiles of the Portuguese stock market index component stocks using a novel approach to the classical capital asset pricing model (CAPM). Specifically, we estimate the CAPM via fractal regressions that allow studying the marginal effects at selected scales. In this way, we can reveal whether the risk is perceived differently by market participants with different investment horizons. Apart from the analysis itself, we provide new statistical insights into the issue of separating and comparing the scale-specific effects with statistical validity. We find several stocks deviating from an expected risk perception homogeneity across investment horizons. This is true for both analysed periods, i.e. before and after the global financial crisis. There are also several stocks that changed their relationship to the market portfolio in between, which has strong implications for possible portfolio construction. The proposed methodology is not limited to financial topics but can be used in any discipline where the scale-specific marginal effects might be of interest.  相似文献   
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6.
One of the questions associated with facilitated problem structuring is how the micro level of actors’ multimodal communications, contributes to the emergence of a macro level, framing the possibilities for action in a workshop. This paper shows a way to study this macro level, building the visualization of the conversations’ structure starting from a boundary games theory micro analysis of the interactions. Our empirical evidence comes from following a group of academic consultants working to define a value proposition for their activity. We focus on analyzing two out of nine workshops that were felt diametrically opposite in terms of facilitation and achievements. Moving from the micro towards an upward level, three configurations building the structure are identified—shifting, branching and converging. The work carried out allows us to: (1) visualize the structure of conversations in a problem structuring context, (2) highlight the role of multimodal communications in building the conversations and (3) construct an interpretation bridging the micro and macro readings of a workshop. This knowledge is useful for facilitators guiding the dynamic of a workshop and for researchers looking forward to understanding how micro level interactions build higher levels of the social phenomenon of intervention.  相似文献   
7.
In this paper we investigate the long-run relationship between public debt and economic growth in the Spanish economy for the period 1851–2013. We develop a cliometric analysis of the debt–growth nexus using novel time series methods. We find some support for a negative relationship between both variables, but no clear evidence of a debt threshold. The estimated long-run elasticity in a one-break model shows a tendency to decrease over time from a nonsignificant 0.011 to a ?0.070, indicating that a 10 percentage increase in the public debt-to-GDP ratio is associated with 0.70 percentage points lower real economic growth. Indeed, we find for the first subsample (1851–1939) either “decoupling” or “saturation,” while in the second subsample (1940–2000) the long-run elasticity coefficient becomes negative and significant. When we extend our analysis up to 2013, we find a break in 1971 coinciding with the twilight of Franco’s dictatorship and the Spanish transition to democracy.  相似文献   
8.
In this paper, we consider the problem of assessing the “level of small-worldness” of a graph and of detecting small-worldness features in real networks. After discussing the limitations of classical approaches, based on the computation of network indicators, we propose a new procedure, which involves the comparison of network structures at different “observation scales”. This allows small-world features to be caught, even if “hidden” deeply into the network structure. Applications of the procedure to both simulated and real data show the effectiveness of the proposal, also in distinguishing between different small-world models and in detecting emerging small-worldness in dynamical networks.  相似文献   
9.
This paper presents a picture of the landscape of consumer law and policy in Ghana and reviews the scope of protection of consumer interests with specific regard to product safety and liability, consumer sales, and telecommunication services. It assesses the legislative and policy framework on consumer contracts, product safety, and unfair commercial practices; discusses the role of national agencies in enforcing safety standards; and highlights some critical consumer issues in telecommunications service delivery. The paper examines the regulatory framework on other consumer issues such as advertising, labelling, and marketing of consumer products; terms and conditions of consumer contracts; and after sales services including the enforcement of guarantees, warranties, refund, and return policies. The paper also discusses the extent of external influence on the development of consumer law and policy in Ghana and reviews the level of interaction with other legal systems and supranational bodies in the three focal areas. The contribution also explores areas of Ghana’s consumer protection framework which could benefit from guidance from the EU transnational model on consumer protection and makes recommendations for the enhancement of the emerging legislative and policy regime on consumer protection in Ghana.  相似文献   
10.
This study examines the influence of the valence of online customer reviews on sales outcomes based on prospect theory. Numerous studies have revealed the importance of customer reviews in online marketing. However, only few studies have explored the impact of online customer reviews on sales outcomes in the dynamic process. Prior studies in behavioral economics literature have indicated that people differently value gains and losses and that losses have more emotional impact than an equivalent amount of gains. This study verifies whether prospect theory applies to the relation between online customer reviews and sales outcomes. Relevant data were collected from Amazon.co.jp, and three statistical models were employed to investigate the relation between the two factors. Major findings confirm that negative customer reviews considerably impact online sales than positive reviews. Furthermore, the findings indicate that the marginal effects of positive and negative reviews decrease with the increase in their volume. The results of this study will enable marketers to compare the relative sales effects of different types of customer reviews and improve the effectiveness of customer service management.  相似文献   
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