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991.
摩托车振动对比测试及舒适性评价 总被引:1,自引:0,他引:1
针对两辆不同企业生产的同排量发动机的摩托车,测试了发动机常用转速下摩托车坐垫和手把位置的振动加速度响应,并进行了对比。根据国际标准ISO2631和ISO5349分别对两辆摩托车进行了振动舒适性评价,形成的摩托车振动舒适性测试和客观评价方法对同类产品有重要的参考价值。 相似文献
992.
从服装舒适性的角度出发,引出服装舒适性整理的重要性.介绍了几种重要的服装舒适性整理方法以及整理后面料的性能比较,为业内研究人员提供一定的指导与参考. 相似文献
993.
The recent Indian Railway budget proposes upgrading and development of fifty railway stations to world class standards. These stations act as crucial transport nodes for effective operation of the railway network and passenger well being. One of the important aspects regarding passenger satisfaction in these places is an acceptable thermal environment. This article studies the thermal comfort of passengers in a large and significant railway station in South India in the summer month of June. The study entails field measurements and questionnaire responses from 402 individuals over a period of fifteen days. The thermal comfort is estimated using the air temperature and the PET (Physiological Equivalent Temperature) scale. The neutral temperature obtained through questionnaire surveys is 31.93 °C. In presence of fair air movement, there is some relaxation to neutral temperature, although the range of relaxation is much narrower than the models presented by other researchers. Comparing the Thermal sensation votes (ASHRAE 7-point scale) with comfort votes (Bedford 7-point scale), it is observed that the passengers exhibit high tolerance and adaptivity. Further, some observations are made on the relationship between the nature of waiting areas and their spatial influence on passenger thermal comfort. 相似文献
994.
Urban waterbodies play important roles in the aesthetics, ecology and human interactions of city life. However, their effect on human comfort has rarely been evaluated. The conference center for the Shanghai World Expo 2010 is located along the waterfront of the Huangpu River. Over 25 days of high temperatures ≥35 °C are predicted during the conference period. Proper planning and construction of littoral zone environments near the waterbodies in the World Expo garden could improve the comfort of visitors. In this study, the effects of the waterbody, vegetation and wind conditions on temperature and humidity in littoral zones were analyzed using on-site measurements and a calculated heat index from the littoral zone of Huansha Lake in Huangxing Park, Shanghai on hot summer days. An index for evaluating human comfort in the littoral zone was then established for use at the Shanghai World Expo Garden. This index was tested at an artificial lake in Luxun Park, Shanghai and its effectiveness was demonstrated. The results showed that during the high temperature hours of a hot summer day, a waterbody can effectively improve human comfort in the littoral zone. The area 10–20 m from the water's edge shows the greatest improvement in thermal comfort. Appropriate landscaping in the littoral area can have a synergistic effect, further improving the effects of the waterbody on human comfort. The data from this study provide scientific guidance for the design of littoral zones near waterbodies in the garden of the Shanghai World Expo 2010. 相似文献
995.
In this paper, the topic of thermal comfort for buildings with double skin façades and single skin façades is demonstrated and discussed. A long-term monitoring was performed in 280 office rooms distributed over 28 buildings in Germany. The survey methods were based on sensor measurements and data simultaneously gathered from questionnaire given to office users. The authors take into consideration the operative temperature, vertical gradient temperature, draught rate, radiation asymmetry, relative humidity and carbon dioxide concentration. The aim is to determine the individual sensory perception of the indoor environment and compare it to the actually measured indoor climate in buildings with double skin façades and single skin façades. In regards to the thermal comfort results, in general, it is shown that double skin façades buildings have slight advantages in relation to single skin façades buildings. 相似文献
996.
阐述了基于坐姿受力状况和计算机辅助几何设计技术相结合的汽车座椅分离式骨架靠背设计方法。首先在保证腰弧曲线的正常形状和保证肩靠与腰靠的正常高度与宽度的前提下,设计了骨架靠背的中心脊线轮廓和边界轮廓线;利用中心脊线和边界线上取等比例点并构造样条线的方法,设计了横向断面线。然后运用双三次混合Coons曲面构造得到靠背的型面方程,并对型面进行详细设计。冲压生产得到靠背并完成座椅总成装配后,通过试验得到座椅的幅频响应特性。结果表明,该座椅骨架靠背的设计方法是合理的,可以有效降低频率响应,改善乘坐舒适性。 相似文献
997.
Look-ahead preview control application to the high-mobility tracked vehicle model with trailing arms
Okhyun Kang Youngjin Park Youn-sik Park Moonsuk Suh 《Journal of Mechanical Science and Technology》2009,23(4):914-917
Preview control involves using forward road information acquired from preview sensors in designing a controller. Preview control,
which is composed of feedback and feed-forward input parts can lead to better performance than feedback control alone. In
this paper, application of the preview control based on the active suspension to tracked vehicles will be introduced. The
suspension unit of the tracked vehicle is in the form of a trailing arm type to increase the wheel travel. Because the preview
control has been developed for the linear time-invariant system, a linearized model of the system is required. A linear model
of the tracked vehicle, which the preview controller is designed based upon, is generated without considering the dynamics
of the track elements for simplification. On the other hand, the nonlinear model, which the performance of the controlled
system is investigated based upon, is generated by using Recurdyn™, commercial software. The nonlinear model includes nonlinear
damping and stiffness characteristics of hydraulic suspension units(HSUs). From the simulation results for RRC 9, performance
enhancement of the preview control will be shown in terms of ride comfort by using ISO 2631 under the assumption that actuators
are ideal and the velocity of the vehicle is constant.
This paper was presented at the 4th Asian Conference on Multibody Dynamics(ACMD2008), Jeju, Korea, August 20–23, 2008.
Okhyun Kang received his B.S. degree in M. E. from Busan National University, Korea, in 2004. He then received his M.S. from KAIST in
2006 and is currently Ph.D candidate at M.E. Engineering at KAIST in Korea.
Youngjin Park received his B.S. and M.S. degrees in M. E. from Seoul National University in 1980 and 1982, respectively. He then received
his Ph.D. degree from University of Michigan in 1987. He is currently a Professor at the School of M. E. at KAIST in Korea.
Younsik Park received a B.S. degree in M. E. from Seoul National University in 1972. He then received his M.S. and Ph.D. degrees from
Iowa State University in 1979 and 1981, respectively. He is currently a Professor at the School of M. E. at KAIST in Korea.
Moonsuk Suh received a B.S. degree in M. E. from Hanyang University in 1976. He then received his M.S. and Ph.D. degrees from Michigan
State University in 1984 and 1989, respectively. Dr. Suh is currently a Principal Researcher at Agency for Defense Development
in Korea. 相似文献
998.
BU Yan XIANG Zhongxia HUANG Tian ZHANG Xu WANG Xinghua 《机械工程学报(英文版)》2009,22(1):21-26
This paper investigates the dynamic design methodology of mountain bikes with rear suspension. Firstly, a multi-rigid body dynamic model of rider and mountain bike coupled system is constructed. The rider model includes 19 skeletons, 18 joints and 118 main muscles. Secondly, to validate the feasibility of the model, an experiment test is designed to reflect the real cycling status. Finally,aiming at enhancing the performance of the rider vibration comfort, the scale parameters of rear suspension are optimized with computer simulation and uniform design. The mathematical model in the vibration performance and the design variables is constructed with regression analysis. The result shows that when the length of side link is 90 mm, the length of connected rod is 336.115 1 mm and the included angle between absorber and side link is 60°, the mountain bike has better vibration comfort. This study and relevant conclusions are of practical importance to the design of the mountain bike's rear suspension system. 相似文献
999.
The thermal environment and thermal comfort of a building are greatly affected by the design of the building interface form. Most contemporary architectural designs consider only the relations between architectural form and architectural beauty. Few studies on the correlation of architectural form and thermal comfort address the influence of architectural form on thermal comfort and thermal environment. These studies are particularly important for gymnasium architectures located in hot and humid areas, which have high requirements for thermal comfort. This paper presents an experimental investigation and an analysis of the effect of the building interface form of gymnasiums on thermal comfort in hot and humid subtropical regions durings ummer. Results showed that the influence of the top interface forms on thermal comfort is mainly dominated by the mean radiant temperature, which could be controlled to improve thermal comfort. The influence of side interface forms on thermal comfort is mainly dominated by air velocity, and thermal comfort could be improved by promoting natural ventilation on the side interface form design to reduce indoor heat. This research enhanced our understanding of the relation between the interface form and the thermal comfort of gymnasiums. In addition, this paper provides a theoretical reference for the sustainable design of gymnasiums in hot and humid climates. 相似文献
1000.
为探究女性身体不同部位对服装的压力感知及其舒适范围,基于物理心理学极限阶梯法原理进行实验测试与计算,推导服装压力舒适阈限。筛选 50 位在校女大学生作为测试受体,依次测试 9个不同部位的服装压力;设计开发双环扣式可连续调节束带,实现束带对人体各测试部位的施加压力尽可能等距变化并保持稳定。得出 9个部位的压力舒适阈限分别为:腹侧点最大,为 2 753 Pa;其次是肩中点和肩胛骨点,分别为1671、1633 Pa;再次是腋下点、后腰侧点、腹凸点和高腰侧点,分别为1 305、1 284、1 260、1 156 Pa;前腰中点和前胸下部的压力舒适阈限最小,为955、937Pa。 相似文献