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41.
学前儿童平板电脑导航按钮交互设计评价指标的建立,有利于交互设计在学前儿童平板电脑中的优化和改良.从学前儿童体验视角出发,创建平板电脑导航按钮交互设计的多维度多层次评价指标,该方法以创建多维度多层次评价指标为基础,根据D-S证据理论设计评价指标的决策矩阵,利用层次分析法确定评价指标权重.最后以优学派儿童平板电脑"童话故事"界面导航按钮8个优化设计方案对比分析与评价为例,验证了所提出方法的合理性与有效性.  相似文献   
42.
随着我国高职教育的迅速发展,以“工学结合”为特色的课程标准广泛应用于高职院校烹饪专业的教学中。食品营养与卫生课程是一门重要的课程,为进一步提升该课程的教学质量,培养学生的职业能力和职业素养。本文结合食品营养与卫生课程教学改革现状,提出教学改革途径,以期实现食品营养与卫生教学质量的进一步提升。  相似文献   
43.
《Business Horizons》2021,64(6):787-797
Global institutions face costly infrastructure disruption from cyberthreats such as ransomware attacks. The global threat of ransomware attacks has continued to increase over time. Although it is important to conduct a cost-benefit evaluation and to weigh the risks prior to engaging, a new emerging option of dealing with ransomware attacks should be considered. I outline an interdisciplinary approach to cybernegotiation combining features of online dispute resolution and terrorist hostage theory. In this novel cyber-based dispute system design, the Wade and seek method is the application of traditional hostage negotiation theory used to help businesses mitigate the costs of ransomware attacks.  相似文献   
44.
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.  相似文献   
45.
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.  相似文献   
46.
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.  相似文献   
47.
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。  相似文献   
48.
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。  相似文献   
49.
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.  相似文献   
50.
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.  相似文献   
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