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1.
大型综合室内亲子乐园属于高大空间,设有游乐设施和游戏的特殊性使得对空间的舒适性要求一致,但是送风气流遇阻严重,室内存在较多气流死角,影响室内空气质量和儿童健康。因此其空调设计不仅需要考虑温度、风速的空间均匀度,还要考虑各点的空气龄和PMV-PPD指标。以天津某亲子乐园为研究对象,利用scSTREAM软件对适用于该房间的辐射供冷加新风、置换通风、混合通风三种空调方式的送风效果进行数值模拟分析,从流场的均匀性、人员的热舒适性等方面对模拟结果进行探讨,研究结果表明辐射供冷加新风方式的空间均匀性和PMV指标最佳,混合通风方式的空气龄最小。 相似文献
2.
J. Giacomin M. S. Shayaa E. Dormegnie L. Richard 《International Journal of Industrial Ergonomics》2004,33(6):56-541
The human perception of rotational hand–arm vibration has been investigated by means of a test rig consisting of a rigid frame, an electrodynamic shaker unit, a rigid steering wheel, a shaft assembly, bearings and an automobile seat. Fifteen subjects were tested while seated in a driving posture. Four equal sensation tests and one annoyance threshold test were performed using sinusoidal excitation at 18 frequencies in the range from 3 to 315 Hz. In order to guarantee the generality of the equal sensation data, the four tests were defined to permit checks of the possible influence of three factors: reference signal amplitude, psychophysical test procedure and temporary threshold shift caused by the test exposure. All equal sensation tests used a reference sinusoid of 63 Hz at either 1.0 or 1.5 m/s2 r.m.s. in amplitude. The four equal sensation curves were similar in shape and suggested a decrease in human sensitivity to hand–arm rotational vibration with increasing frequency. The slopes of the equal sensation curves changed at transition points of approximately 6.3 and 63 Hz. A frequency weighting, called Ws, was developed for the purpose of evaluating steering wheel rotational vibration. The proposed Ws has a slope of 0 dB per octave over the frequency range from 3 to 6.3 Hz, a slope of −6 dB per octave from 6.3 to 50 Hz, a slope of 0 dB per octave from 50 to 160 Hz and a slope of −10 dB per octave from 160 to 315 Hz. Ws provides a possible alternative to the existing Wh frequency weighting defined in International Standards Organisation 5349-1 (2001) and British Standards Institution BS 6842 (1987).
Relevance to industry
For the manufacturers of tyres, steering systems and other vehicular components the proposed Ws frequency weighting provides a more accurate representation of human perception of steering wheel rotational vibration than the Wh weighting of ISO 5349-1 and BS6842. 相似文献
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童克波 《自动化与仪器仪表》2014,(6):200-202
电梯作为高层建筑中大量使用的机电一体化设备,为了改善乘坐的舒适度、节能,电梯的控制系统中广泛使用交流变压变频调速,作为变压变频控制装置,变频器以其成熟的技术和可靠性被应用于电梯控制系统中,与其他类型交流调速系统相比具有运行效率高、节能效果显著,电梯运行乘坐舒适等优点。本文以日本富士电梯专用变频器5000G11UD为控制器,组成电梯变频调速系统,从理论上分析了实现电梯乘坐舒适、节能的控制关键点,并给出了实际操作方法,具体应用取得了较好的效果。 相似文献
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This paper presents a method for generating gaits for a one-legged articulated hopping robot. A static optimization procedure
produces the initial joint velocities for the flight phase, using the principle of conservation of angular momentum and assuming
(nearly) passive flight. Two novel objective functions for this static optimization enable one to choose different gaits by
simply changing a few parameters. A dynamic optimization procedure yields a solution for the flight trajectory that minimizes
control effort. The stance phase (when the foot is touching the ground) becomes a standard two point boundary value problem,
also solved with a dynamic optimization procedure. During the stance phase, the physical joint limitations, ground reaction
forces, and the trajectory of the zero-moment point all constrain the solution. After these single-phase optimizations, a
complete-cycle optimization procedure, incorporating both flight and stance phases, further reduces the control effort and
balances the motion phases. In simulation, the leg hops on even ground and up stairs, exhibiting energy-efficient and intuitively
satisfying gaits. 相似文献
8.
代杰 《自动化与信息工程》2009,30(3):46-48
电梯作为现代高层建筑的垂直交通工具,得到了快速发展,其拖动技术已经发展到了调频调压调速,其逻辑控制也由PLC代替原来的继电器控制。文章在已有的通用变频器的基础上,采用PLC对电梯进行控制,通过合理的选择和设计,提高了电梯的控制水平,并改善了电梯运行的舒适感,使电梯达到了较为理想的控制效果。 相似文献
9.
本文在深入研究8B10B编、解码原理的基础上,利用其DWS特性,用Verilog HDL语言实现编、解码算法的描述,并通了modelsim仿真.在ISE9.1i平台上综合后下载到FPGA上实现具体的硬件电路,同时分析了系统各项性能.在PCI Express总线上,实现了一个性能良好的8810B编解码系统,它具有很好的可移植性以及一定的实用价值. 相似文献
10.
Quality Function Deployment is proposed as an effective design method to integrate ergonomics needs and comfort into hand tool design because it explicitly addresses the translation of customer needs into engineering characteristics. A crucial step during QFD concerns the linking of engineering characteristics to customer needs in the House of Quality by the design team. It is generally assumed (looking at all the QFD success stories) that design teams can accurately predict the correlations between customer needs and engineering characteristics (also referred to as “Whats”/“Hows” correlations). This paper explicitly tests this assumption by comparing the “Whats”/“Hows” correlations estimated by a design team with those observed in a systematic user evaluation study, which has not been done before. Testing the assumption is important, because inaccurate estimates may lead to ergonomically ineffective (re)design of hand tools and a waste of company resources. Results revealed that the design team's correlation estimates were not as accurate as is generally assumed. Twenty-five percent of the estimates differed significantly with those observed in the user evaluation study. Thus, QFD is a useful method to assist design teams in designing ergonomically more comfortable hand tools, but only on the condition that the correlations between customer needs and engineering characteristics are validated, preferably by means of a systematic user evaluation study. 相似文献