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631.
本文通过对产销量大的低配车型顶盖合拼的工艺优化,对前横梁、中横梁和后横梁的上件工艺方案及其定位夹具优化,开发新一代中横梁、后横梁的定位夹具,将中横梁、前横梁等零件的定位方法模块化,形成一种整体解决方案,具有较高的应用推广价值.  相似文献   
632.
文章从分析定位标定系统海试数据处理结果入手,提出利用拟合检定方法评估水声测量定位精度。仿真测试和海试数据验证结果表明,利用拟合检定方法评估的水声定位精度比实际标定精度偏小,基本可以反映实际测量数据的标定精度,作出置信分析的拟合评估精度值更接近实际标定精度值。此方法可以作为定位标定的补充,给出测量精度指标的估计值。  相似文献   
633.
遥控潜器工作母船动力定位系统   总被引:2,自引:1,他引:1  
针对我国第一艘装备动力定位系统的遥控潜器工作母船,本文重点介绍了动力定位系统的运动控制数学模型,基本控制原理,系统组成,工作方式,综合显示与集中操纵设计思想,遥控潜器工作母船已完成航行试验,结果表明:在最大风速13米/秒时,动力定位系统控位均方差在5m之内。长期实际应用证明:系统运动可靠,人机界面形象直观,操纵灵活。  相似文献   
634.
章建峰  詹佳  董九洋  缪凯祥 《船舶工程》2019,41(S1):170-173
船舶动力定位系统,主要实现船舶在要求的作业活动中保持设定的经纬度或者相对于海床的固定位置,或者期望的运动方向,即在风、流、浪产生的力作用在船舶的情况下,动力定位系统能够通过各推进器控制船舶,并使船舶按照操作者的指令移动、保持位置或航向,同时,符合相应规范要求。本文主要介绍船舶动力定位系统的总体设计,包括硬件框架设计和软件框架设计。最后,给出了基于这种总体设计的动力定位系统实船试验结果。  相似文献   
635.
Cycling and walking are being promoted in many urban areas as alternatives to motorised transport for health, environmental, and financial reasons. The reduced congestion and resulting decrease in the overall amount of pollution reduced can be expected to result in health benefits for the community. However, active commuters, due to their increased respiration rates and often increased travel times can expect to receive larger doses of air pollution compared with those using motorised forms of transport. However, given the large dropoff in concentrations away from a road, it can be expected that significant reductions can be achieved even with relatively small increases in separation between the path of cyclists/pedestrians and motor vehicles.This study presents a simple methodology for calculating the separation needed for cyclists and pedestrians to experience the same air pollution dose as car commuters. An example is given based on carbon monoxide (CO) data collected in a field campaign consisting of a car driver, a cyclist and a pedestrian travelling on a 2600 metre loop of road in Auckland. For this case study, the estimated distance from the centreline needed for cyclists and pedestrians to receive an equivalent dose of CO as motorists was found to range from 5.8 to 14.2 m depending on the commuting mode and the dispersion state of the atmosphere at the site. This was equal to a CO concentration reduction of 0.1–0.14 ppm per metre. Recommendations on facility modifications and route selections have been made to make active mode commuting safer.  相似文献   
636.
乔国瑞 《船舶》2020,(2):29-35
管道挖沟动力定位工程船是一艘集首部拖缆作业系统、尾部拖缆作业系统以及其他多项水下作业功能的海底施工作业船舶,为配合其作业功能,对诸多大型作业设备进行结构加强,并创新性地设计凹形首柱拖缆槽和导缆圆尾。通过计算分析,对横剖面进行优化,校核总纵强度以及校核主要设备加强结构的局部强度,对船体振动进行评估并采取一定的减振措施。  相似文献   
637.
This study examines the users’ acceptance and usage of mobile payments, focusing on the mobile ticketing technologies applied in a public transport context. We investigate the main predictors of the intention to use mobile ticketing and the relation between those predictors, considering the prominent literature on users’ technology acceptance background and extending the knowledge through an innovative contribution. The main models of reference in this study are the Technology Acceptance Model (TAM), the Diffusion of Innovation Model (DOI) and the Unified Theory of Acceptance and Use of Technology (UTAUT) model. The new model that we proposed is called the Integrated Model on Mobile Payment Acceptance (IMMPA), and it was designed specifically for mobile payments in the public transport, on the basis of the models previously mentioned. It was developed by mixing the variables of the existing models and adding new ones tailored to the mobile payment/ticketing framework. The theoretical framework was tested using the Structural Equation Models. The results show that the intention to use a technology is affected by the Usefulness, Ease of use and the Security of that technology. Moreover, the Usefulness is simultaneously influenced by the Ease of use, the Compatibility with users’ values and needs and their Attitude towards mobile services. Furthermore, the model confirms the direct relation between the intention to use a technology and its actual usage. The new predictor, that is the Attitude towards mobile services, includes those requirements that every mobile ticketing payment must address in this context: complete information, further information about time and delay, speed of use, intuitive interface, and path customisation. Another new construct detected is the Security, in reference to mobile payment. Because it could represent an obstacle to mobile ticketing distribution, it must be considered by market operators. The originality of the paper addresses the realisation of a new model, the IMMPA, which was specifically designed for mobile payment in the public transport.  相似文献   
638.
639.
针对城市轨道交通信号系统测速定位,详细分析了常用的轮轴速度传感器、多普勒雷达及加速度计的测速原理,并深入分析了各传感器的误差影响因素、失效模式以及传感器的复杂性。对目前常用的4种组合测速定位方案,从方案的测量精度、成本、系统可靠性、设备安装、安全性评估等方面进行了分析比较,给出了各种测速定位方案的优缺点。分析比较结果表明,速度传感器+加速度计+应答器的组合测速定位方案具有一定的发展优势。  相似文献   
640.
In this paper, graphical-user-interface (GUI) software for simulation and fuzzy-logic control of a remotely operated vehicle (ROV) using MATLABTM GUI Designing Environment is proposed. The proposed ROV...  相似文献   
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