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21.
Although researchers and practitioners increasingly focus on health promotion in organizations, research has been mainly fragmented and fails to integrate different organizational levels in terms of their effects on employee health. Drawing on organizational climate and social identity research, we present a cascading model of organizational health climate and demonstrate how and when leaders' perceptions of organizational health climate are linked to employee well-being. We tested our model in two multisource studies (NStudy 1 = 65 leaders and 291 employees; NStudy 2 = 401 leader–employee dyads). Results showed that leaders' perceptions of organizational health climate were positively related to their health mindsets (i.e., their health awareness). These in turn were positively associated with their health-promoting leadership behavior, which ultimately went along with better employee well-being. Additionally, in Study 1, the relationship between perceived organizational health climate and leaders' health mindsets was moderated by their organizational identification. High leader identification strengthened the relationship between perceived organizational health climate and leaders' health mindsets. These findings have important implications for theory and practice as they show how the dynamics of an organizational health climate can unfold in organizations and how it is related to employee well-being via the novel concept of health-promoting leadership.  相似文献   
22.
The decisions a researcher makes at the model building stage are crucial for parameter identification. This paper contains a number of applied tips for solving identifiability problems and improving the strength of DSGE model parameter identification by fine-tuning the (1) choice of observables, (2) functional specifications, (3) model features and (4) choice of structural shocks. We offer a formal approach based on well-established diagnostics and indicators to uncover and address both theoretical (yes/no) identifiability issues and weak identification from a Bayesian perspective. The concepts are illustrated by two exemplary models that demonstrate the identification properties of different investment adjustment cost specifications and output-gap definitions. Our results provide theoretical support for the use of growth adjustment costs, investment-specific technology, and partial inflation indexation.  相似文献   
23.
Air transport deregulation has lead to an increase of air traffic, together with a reduction of air fares. Air fare reduction has narrowed operational margins of airlines, bringing financial and employment instability. This has brought airlines to pay increasing attention to flying costs reduction. Two important components of flying costs airlines can try to cut modifying the planned flight are en route charges and operational costs. We rely on Demand Data Repository (DDR2) data to calculate deviations from planned flight trajectories to analyse the extent to what airlines try to cut operational costs making shorter flights than planned if possible, and cut en route charges providing a planned flight with lower en route charges than the planned flight. Our findings show that there is no generalised strategy among airlines to reduce en-route charges asking for deviations of the planned route. On the other hand, airlines are achieving savings of operational costs regularly. Higher savings per nautical mile are obtained in night flights, with longer planned distance and operated by low cost carriers.  相似文献   
24.
This research assesses the impact of the integration of Continuous Climb operations (CCOs) on Air Traffic Control (ATC) workload. The methodology encompasses different modules: CCO, standard departing and arriving trajectories extracted from an external database, an ad-hoc algorithm for detecting and solving conflicts, and an ATC-workload model with the inclusion of CCO-task modifications. Monte Carlo simulations evaluates different combinations of these modules. Then, a sensitivity analysis is performed to evaluate two parameters: the impact of the calibration of the maximum ATC workload and the percentage increase of the CCO tasks on the ATC workload. The methodology is applied to a case study at Palma airport in Spain. Extensive numerical simulations are executed based on the integration of CCOs into the system from 0% to 100%. The integration of CCOs implies the increase of the ATC workload in the Control Tower (TWR) and the reduction in the Approach Control Centre (APP). The sensitivity analysis shows that the decrease in the increase of CCO-task workload barely affects the number of CCOs that can be operated without exceeding the workload limits. Conversely, the reduction of the ATC workload calibration allows the integration of CCOs around 50% in the case of 90% TWR calibration and up to 100% in the case of 80%.  相似文献   
25.
This paper proposes to analyze control strategies for arrival air traffic at an airport using a classical queuing model. The parameters of our model are estimated by means of a data-driven analysis of two years of radar tracks and flight plans for arrival flights at Tokyo International Airport from 2016 to 2017. Our results show that increasing the capacity with one or two more aircraft in the airspace up to 60 NM around the airport significantly mitigates arrival delays, even when assuming future, increased arrival traffic volumes. The outcomes of this study provide insights into the effectiveness of arrival control strategies and are seen as a means to recommend scenarios to be further analyzed with human-in-the-loop simulations.  相似文献   
26.
空铁联运是综合交通一体化发展的重要组成部分,欧美国家已积累了许多经验,我国也逐渐出现一批与民航机场建设在一起的铁路车站,探索空铁联运的发展模式。对现有铁路空铁联运车站的布局特征、服务特征和运量特征进行分析,总结规律、提出建议,为我国空铁联运的发展方向提供参考。  相似文献   
27.
基于星载极化SAR数据的农作物分类识别进展评述   总被引:1,自引:0,他引:1  
[目的]农作物播种面积信息不仅可为农情监测和作物估产提供重要的数据保障,还是国家制定粮食政策和经济计划的重要依据。快速、准确地获取农作物播种面积信息能为农业生产管理提供决策支持。极化SAR不受云雨天气的影响,在农作物遥感监测方面具有巨大的应用潜力,有效利用极化SAR数据进行农作物识别研究对促进雷达技术在国家农业遥感监测和农业供给侧结构性改革中发挥更大作用具有重要意义。[方法]以星载极化SAR技术的发展过程为论述主线,从单、双极化SAR数据,单、双极化SAR数据结合光学影像,全极化SAR数据三个发展阶段,对极化SAR数据在农作物分类识别中的研究与应用进行总结,并对比分析不同的识别特征、融合算法以及分类算法的优缺点。[结果]以往研究存在以下不足:当前研究多以识别水稻为主,对于难以识别的旱地作物研究较少;目前对旱地作物识别精度不高,平均识别精度不足85%;缺乏对不同作物散射机制及其随时相变化的研究,导致分类算法机理性不足,普适性较差。[结论]在今后的研究中,旱地作物散射机制的定量确定,如何利用散射机制及其变化来提高旱地作物遥感识别精度和普适性;目前分类算法大都是基于光学影像设计,如何利用SAR特殊的成像方式优化设计适用于极化SAR数据的分类算法,得到更高的分类精度;如何更好的跟光学遥感等多源数据(光学数据、GIS数据等)结合来提高精度,将成为未来极化SAR农作物识别中三个亟需重点解决的问题。  相似文献   
28.
Anecdotal evidence has shown that retail price promotions can help small and medium-sized retailers enhance their sales, and thus profits. However, most marketing managers usually stop a promotion after a certain duration. This study aims to explain why these retailers discontinue their price promotion. Our approach posits that overall contributions of a price promotion to the product profit progressively diminish with time. In this study, we present a theoretical framework to explain the relationship between duration and profit effects of price promotion and propose statistical models to empirically examine this framework using point-of-sale (POS) data. Our findings provide empirical support that the effect of price promotion on the product profit has a downward trend with elapsed time. The results are helpful for marketers to understand how price promotions dynamically influence product profit and when the promotion should be terminated.  相似文献   
29.
黄昱方  刘雪洁 《技术经济》2020,39(10):181-188
基于社会认同理论,研究人力资源管理动机归因(HRA)对知识共享的影响以及组织认同的中介作用机制,同时探讨任务互依性的调节作用。通过602份员工企业员工的调研数据,采用Mplus7.0软件构建有调节的中介模型进行检验。结果表明:承诺型HRA促进知识分享,控制型HRA削弱知识分享,组织认同完全中介了这一过程;任务互依性强化了组织认同与知识分享的正向关系,在任务互依性较高的情况下,强化了承诺型HRA对知识分享的正向影响,削弱了控制型HRA对知识分享的负向影响。  相似文献   
30.
Multi-airport systems are growing in number and size globally, despite being afflicted by known inefficiencies due to the interferences between the flows of neighbouring airports. A macroscopic empirical approach is proposed in this paper to estimate the capacity penalties and demonstrated by a numerical case study for Beijing, which is projected to become one of the busiest metroplexes in Asia. The Pareto envelopes of the theoretical and observed peak hour capacities are statistically analysed to quantify the penalties in a comparable metroplex and are subsequently modulated by a sigmoid correlation function. The analysis predicts the practical capacity of Daxing, the penalty incurred by the pre-existing Capital airport and by the total multi-airport system. Various findings are drawn and discussed, highlighting the needs for further research.  相似文献   
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