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排序方式: 共有1414条查询结果,搜索用时 31 毫秒
651.
This study proposes a methodological framework to incorporate latent factors, including direct and indirect perceptions, as the explanatory variables in a discrete choice models using revealed preference and stated preference data sets. The methodology requires the estimation of a model system comprising of a discrete choice model and the structural and measurement equations of a latent variable model. The application involves the evaluation of responses to the new high occupancy vehicle (HOV) lanes on the Sun Yat‐Sen Freeway in Taiwan. The results obtained from this study provide valuable insights into the planning and assessment of HOV lanes. 相似文献
652.
在施工阶段推行一切以数据说话,一切以书面为根据,做好提前预控,对重点部位、关键工序进行动态控制。在施工管理过程中,抓"重点部位"的质量控制,对工程施工做到全过程、全方位的质量监控,从而有效的实现工程项目施工的全面质量控制。 相似文献
653.
N. Oppenchaim 《Recherche - Transports - Sécurité》2011,27(2):93-103
Do the working-class teenagers have a specific and homogeneous use of the space outside their neighbourhood? Do they have different practices of mobility when they live in “Zones Urbaines Sensibles” (ZUS)? These questions have hardly been investigated in contrast to these teenagers’ use of the space inside their neighbourhood. Yet, in spite of a mobility potential lower than that of other teenagers, they spend a lot of time outside their neighbourhood. Among these teenagers, those residing in the ZUS experiment personal autonomy at a younger age in taking public transportation. Also, one notes a greater immobility of girls. Beyond these gender disparities, a closer look at the daily mobility reveals five predominant ways of using the space outside the neighbourhood — public transportation being part of this space. These ways are tightly linked to the nature of the relationship with that neighbourhood. These five predominant ways, influenced by social and territorial variables, depict the heterogeneity of the inhabitants of the ZUS and of the current working class. 相似文献
654.
Pinyung Chen Shinhung Chang Rongshun Chen 《International Journal of Automotive Technology》2017,18(4):663-670
This paper is aimed to propose a decoupled self-tuning proportional plus integral (PI) controller with simple law for an idling stop system applied to scooters. An integrated starter generator (ISG) of the idling stop system is designed with a high efficiency permanent magnet synchronous motor (PMSM). The PMSM used as an ISG must have a high torque characteristic to ensure that the engine can be accelerated up to firing speed. A conventional and useful control algorithm named PI control is unable to handle motor current very well for dynamic load, parametric variation, and external disturbance, especially in a vehicle application. Therefore, a robust algorithm for current control in an ISG is proposed. The decoupled selftuning PI controller based on the Lyapunov stability theorem is utilized to guarantee the control performance. Numerical simulations demonstrate the effectiveness of the proposed control algorithm. Experimental results show that the engine of a 150 cm3 scooter can be cranked to reach firing speed by a ISG within 0.1?0.2 second. The proposed method is simple, robust, as well as stable for idling stop system, and can be effectively implemented. 相似文献
655.
锰粉加工工人心血管功能的调查研究 总被引:2,自引:1,他引:1
对 55 名锰粉加工工人和 56 名对照工人的调查结果显示,工人工作地点 Mn O2 浓度几何均值为 196 m g/m 3 (锰尘 017~22.24 m g/m 3 ),样品超标率 887% 。接触组头晕头痛、睡眠障碍、容易疲劳和记忆不良的主诉率明显高于对照组( P<005~001)。接触组和对照组的心电图异常、高血压和低舒张压检出率未见显著性差异,其心率、 P R间期、 Q R S波、收缩压和舒张压的均值比较也没有显著性差异。接触组心电图异常和低舒张压的 O R分别是 1.56(95% 可信区间为 070~3.50)和 2.08(95% 可信区间为 018~23.57)。 相似文献
656.
Chang Doo Jang Tae Hoon Kim Dae Eun Ko Thomas Lamb Yun Sok Ha 《Journal of Marine Science and Technology》2005,10(4):211-216
In a shipyard, line heating and triangle heating are two major processes carried out by skilled workers to form curved plates
in various shapes under various heating conditions. There have been many studies on line heating, but triangle heating has
rarely been studied owing to its complicated heating process with irregular multiheating paths and highly concentrated heat
input. Triangle heating is the most labor-intensive job. Hence, it is essential for most shipyards to study the automation,
as well as the improvement, of the triangle heating process in order to increase hull-forming productivity. In this study,
a pioneering attempt to simulate triangle heating was made. A circular disk-spring model is proposed as an analysis model
for the elastoplastic procedure of triangle heating, and the inherent strain method is also used to analyze the deformation
of plates. The results of the simulation were compared with those of experiments and showed good agreement. It is shown that
the present approach and the model used in this study are effective and efficient for simulating triangle heating for the
steel plate forming process in shipbuilding. 相似文献
657.
658.
分析了在军用机场规划建设转运站的必要性,阐述了军用机场现状,探讨了军用机场转运站的保障功能、建设内容与能力标准要求,并提出了需关注的相关配套措施,为军用机场转运站规划建设提供理论指导。 相似文献
659.
660.