The evaluation of Istanbul airspace design from the perspective of complexity and safety

The approach, descent, and climb phases of flights in terminal maneuvering areas (TMAs) are some of the critical parts of a flight in which more than half of accidents happen. For an ANSP (Air Navigation Service Provider), to fulfill the responsibility with a high-quality service degree while maintaining safety, these difficult areas should be designed carefully and equipped with the most efficient procedures. Point merge system (PMS), which is defined as a systemized method for sequencing arrival flows, is launched in Istanbul's new TMA (LTFM TMA) being designed by DHMI (Devlet Hava Meydanları Isletmesi) to improve safety and efficiency. In this paper, the airspace complexity is based on adjusted density and structural index, and safety indicators. To investigate the effects of the radical changes made in re-organized LTFM TMA on the safety issue in comparison with the previous terminal maneuvering area, LTBA TMA, six months' data consisting of 75215 arrival and departure flights are used. Results reflect that the LTFM TMA, one of the world's busiest terminal airspaces, has statistically significantly lower scores in terms of conflict numbers per aircraft, complexity metrics, adjusted density, the hour of interactions, and flight hours than LTBA TMA. Lastly, there exists no longer a significant relationship between conflict types and complexity after launching the new design and structure.     

离心式血液泵水力特性设计及其试验研究

借助商业软件NREC开展离心式血液泵的水力特性设计,其设计流量为5 L/min,设计转速为5000 r/min,得到离心叶轮和蜗壳的三维结构设计方案,并针对其全通道网格进行设计工况下三维流场的定常数值模拟研究.对其溶血性指标进行分析,发现离心式血液泵中95％ 区域切应力小于150 Pa,最大切应力小于500 Pa,满足人体对血液泵溶血性的要求.搭建离心式血液泵流量-压升特性试验测试平台,以质量分数为0.06％ 的黄原胶溶液为流动介质进行试验研究,试验结果显示在设计转速下的实际体积流量偏大于设计流量,整体压升在6550 Pa左右.     

Using CRM to Model Firm Performance in a Business-to-Business Market

Customer relationship management (CRM) is the widely accepted approach for gathering, examining, understanding and translating information related to customers into managerial action. CRM is investigated in the context of new product performance (NPP). CRM enhances NPP as well as firm performance. This study investigates the impact of CRM on NPP through the moderation of top management support and an innovative culture, as well as the impact of CRM on firm performance through the mediation of NPP. A questionnaire survey is used for data collection from marketing managers of 159 firms in Pakistan in the B-to-B market. Hypotheses were tested using SEM in SMART PLS. This research shows that CRM directly affects firm performance, while NPP partially mediates the relationship of CRM and firm performance. These findings have significant implications for the practitioner. This study delivers insights to managers and academicians about the role of CRM in enhancing NPP and improving firm performance. In general, the study provides new insights into CRM by integrating top management support and an innovative culture. The research extends our understanding that top management support and innovative culture do not moderate the relationship of CRM with new product performance in a B-to-B context.     

Some issues in blockchain for accounting and the supply chain,with an application of distributed databases to virtual organizations

This paper reviews some recent blockchain‐based applications for information capture, distribution and preservation. As part of that review, this paper examines two key concerns with current blockchain designs for accounting and supply chain transactions: data independence and multiple semantic models for the same information distribution problem. Blockchain applications typically integrate database, application and presentation tiers all in the same ledger. This results in a general inability to query information in the ledger and other concerns. Further, since most applications appear to be private blockchain applications, there is a concern of agents needing to accommodate multiple blockchains depending on who their trading partners are and what they request. Finally, this paper uses a distributed database to design a ‘blockchain‐like’ system for virtual organizations.     

基于模态应变能密度理论的网架结构损伤识别方法

为了研究网架结构的损伤检测方法,根据应变能密度理论,提出采用单元模态应变能密度差值作为网架结构损伤识别指标的方法,以损伤单元模态应变能密度差值的大小初步确定单元的损伤程度。分析了5种具有代表性的损伤工况,并在数值计算结果中引入了白噪声。结果显示,在一阶模态下,针对单损伤、多损伤和轻微损伤、严重损伤等不同损伤工况,损伤杆件的模态应变能密度差值均为高值。因此,该方法可以有效识别出网架结构的损伤位置,根据损伤单元的模态应变能密度差值大小初步确定单元的损伤程度,且在一定的噪声水平下具有较强的鲁棒性,对网架结构损伤识别具有参考价值。     

政府投资工程总承包项目设计优化认定与收益归属研究

工程总承包模式以设计与施工的高度融合,日益在建筑业受到青睐。但由于政府投资项目中存在有关结余资金上缴国库等规定,容易导致政府投资工程总承包项目下设计优化产生的成果是进行分成或作为结余资金上缴界定不清。鉴于此,本文通过政策文件,并结合政府投资项目特点,分析政府投资工程总承包项目设计优化的情形认定以及在不同结算依据和合同计价方式下设计优化收益归属的界定,为有效激励总承包单位积极进行设计优化奠定基础。     

Examining the change in wellbeing following a holiday

Building on existing evidence that tourism contributes to wellbeing, this study aims to investigate how both hedonic and eudaimonic wellbeing changes after a holiday. A longitudinal inquiry involving three waves of observation (during, the fourth week, and the eighth week following a holiday) was carried out in five tourism cities in China, using Latent Growth Curve models to analyze change. Results suggest that life satisfaction – an indicator of hedonic wellbeing – does not decline as expected whereas other indicators of hedonic wellbeing declined dramatically in the first month and then mildly in the second month following a holiday. Comparatively, eudaimonic wellbeing declined gradually and mildly during the same two-month intervals. Higher levels of optimal tourism experiences predicted slower declines of both hedonic and eudaimonic wellbeing. Theoretical, methodological, and practical implications are discussed.     

Value co-creation in sustainable tourism: A service-dominant logic approach

To mainstream sustainability, we need to understand the value gained from sustainability by users. We apply a user-centred design methodology to develop an agile, iterative, incremental and reflexive process to understand the sustainability value proposition for Lufthansa City Center travel agents. We analyse the failure of sustainability communications within the online platforms used by these agents and explore why the agents factor out sustainability information during the customer sales process. We identify how agents and customers understand sustainability, and we explore opportunities to co-create sustainability value. Furthermore, we prototype, and then test, methods of empowering travel agents to communicate sustainability to their customers as a value-adding proposition.     

Assessing job crafting competencies to predict tradeoffs between competing outcomes

We introduce the job crafting competency construct and apply it to predict tradeoffs between competing outcomes that are inherent in job crafting, like performance and well-being or engagement and withdrawal. Job crafting competencies are the clusters of individual knowledge, skills, and abilities that are necessary to achieve personal objectives through effective job crafting problem-solving. We create a framework of job crafting competencies consisting of comprehensive/simplistic heuristic information use and approach/avoidance problem-solving skills. In Study 1, we operationalize competencies as profiles demonstrated through an aptitude-oriented assessment that predicts differences in outcomes. Five distinct profiles emerged in a sample of 174 workers. The high-volume analytic problem-solving profile was associated with higher performance and strain, while the ambivalent acquiescence profile was associated with lower performance and strain. The practical problem-solving profile minimized tradeoffs between performance and strain. Rapid problem-solving and low-volume analytic problem-solving profiles were variants in between these other patterns. Study 2 used a survey of 323 workers to support the uniqueness of the five competencies, and their relationships with approach/avoidance job crafting, engagement, and withdrawal. The research identifies a new job crafting individual difference (job crafting competencies) to delineate outcomes and tradeoffs according to unique competency profiles.     

参数化机械设计中的线图处理

在机械设计中往往需要进行线图处理,本文介绍了使用VB语言对V带轮、齿轮等零件在设计时须应用线图处理设计的一种思路和方法,从而使计算机语言与机械设计紧密结合,提高设计的精准度,提高设计效率达到事半功倍的效果。