早晚航班对飞行员疲劳程度的影响

航空公司为了提高飞机利用率,导致早晚班的比重明显增加.由于飞行员生物节律的改变,致使其疲劳程度加深.为了保证飞行安全,减缓飞行疲劳,合理排班,需要对执行早晚班的飞行员的疲劳系数进行研究.通过对20名飞行员以及10名飞行学员进行电话访谈,了解到他们早晚班的疲劳程度,进而改进西南航空局可用机组疲劳系数的计算公式,优化了每名飞行员早晚班疲劳系数的计算公式.     

二噁英的理化性质及在乳及乳制品中污染的研究进展

本文主要分析了二噁英的理化性质,重点介绍了乳及乳制品中二噁英的污染情况,并提出有效措施给予预防和解决,以有效降低二噁英在乳及乳制品中的危害性,确保乳及乳制品行业的健康发展。通过对二噁英的理化性质进行研究,为乳及乳制品的安全生产提供可靠保障,以实现经济与社会效益的最大化。     

基于标准数据的创新程度提升路径研究

创新程度在资源配置中的作用日趋明显，但目前创新程度常以专利作为测量值。随着标准在产业发展中引导性增强，作为创新重要产出的标准在创新程度提升中的地位日渐凸显。提出一个以标准数据为依据，通过对标准创新程度值的测量，结合国际国内创新程度四分图模型，研究具体领域创新程度提升路径。以信息技术应用领域标准为分析对象，结合国际标准化组织颁布标准和中国标准，确定信息技术在各应用领域创新现状。结果显示：信息技术在办公系统和银行业务两个领域应用的国际国内创新程度都很低，应在完成产业升级后逐渐淘汰；其在健康关怀领域应用的国际发展前景良好但国内创新程度很低，是重点研究领域。随后，对信息技术在健康关怀领域应用的国际和国内标准具体内容进行对比分析，发现中国与国际发展存在差距，并以国际国内创新程度为依据对位于四分图不同区域的信息技术应用领域创新程度提升提出合理建议。     

The effects of credit default swaps on corporate investment

ABSTRACT

This paper examines how credit default swaps (CDS) affect the corporate investment of the referenced entities. We document a significant reduction in corporate investment after CDS trading, a result that is robust to alternative model specifications and a set of endogeneity tests. Our findings of the increased firm risk and cost of capital support the costly external capital channel. The cross-sectional variations in CDS effects demonstrate that both reduced monitoring and the empty creditor problem might be the underlying forces driving the costly external capital channel. Our additional analysis implies that CDS trading is associated with an enhancement in investment efficiency for firms that are prone to overinvestment.     

Capital asset pricing model in Portugal: Evidence from fractal regressions

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.     

The Structure of Problem Structuring Conversations: A Boundary Games Approach

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.     

Public debt and economic growth in Spain, 1851–2013

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.     

Structural comparisons of networks and model-based detection of small-worldness

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.     

What We Should Know About House Reconstruction Costs?

The Journal of Real Estate Finance and Economics - This paper presents two important analyses, which have been derived from a rich dataset supplied by an important Property & Casualty...