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171.
停车产业化政策研究   总被引:2,自引:0,他引:2  
为了解决机动化带来的停车问题,在我国推动停车事业产业化发展是大势所趋。介绍了一些国家和城市的停车产业化政策,分析了目前制约停车产业化发展的因素,并以北京市“停车难”的典型区域为案例,进行了增设停车场方案的投资回收期估算。认为在必要的政策扶持下,停车场可以实现产业化发展,投资者可以获得经济回报。最后,提出了一些促进停车产业化发展的政策建议。  相似文献   
172.
结合上海市徐汇区黄浦江滨水区的规划研究,提出该地区的规划功能定位及其一系列的综合开发构想。打造徐汇滨水区成为联合国“人居.环境”的典范工程。  相似文献   
173.
黄河兰州市区段河道规划与整治   总被引:1,自引:0,他引:1  
黄河兰州市区 4 5km河段经过建国以来五十多年的规划建设 ,已经建成了能够防御黄河百年一遇流量 6 50 0m3 /s洪水的河堤 4 5.4km ,黄河 4 0km风情线已初具规模 ,在黄河两岸沿滨河绿带建设成了开放式大型带状公园 ,逐步提高了兰州市的综合防洪能力  相似文献   
174.
The importance of vehicle safety cannot be exaggerated in today’s mobile societies. Many manufacturers, associates related to vehicles and universities make an effort to improve vehicle safety by developing new technologies, applying high strength steel to the body structure etc. However, the majority of these efforts are focused on decreasing injury. It is absolutely important to minimize injury, but a more important aspect is coping with vehicle accidents. That is, As undeniably important as it is to minimize potential injuries, it is critical that experts focus on developing ways to keep drivers out of situations likely to lead to crashes in the first place. The purpose of this paper is to determine what the most critical factor is when coping with an unfamiliar driving situation. The answer is to provide a wide-open field of vision, especially for the driver. The driver’s field of vision is obstructed by the vehicle’s A-pillar. To solve this, the A-pillar obstruction angle, which is the angle between the driver’s eyes and the A-pillar should be decreased. This paper purposes three-methods for decreasing this angle structurally and applying a slim A-pillar which is as the best solution to decrease the A-pillar obstruction angle and ensure the drivers field of vision at the same time  相似文献   
175.
A 3000 cc diesel engine attached to an engine dynamo was used to test three newly developed electrostatic Diesel Particulate matter filtration Systems (DPS 1, 2, and 3) under four steady-state engine operating conditions: idle, 2000 rpm with no load, and 2000 rpm under 25% and 50% loads. Of the two developed alternatives, DPS 1 and DPS 2, DPS 2 comprises an ionization section, electrostatic field additional section and Flow-Through Filter (FTF), which achieved almost 90% removal of particulate matter (PM) under the engine’s operating conditions, and the efficiency of the FTF was maintained between 20% and 50%. Comparing the long-term performance of DPS 2 and DPS 3 (effectively a serial combination of two DPS 2s) with a commercially-available Diesel Particulate Filter (DPF), the DPS 2 and DPS 3 achieved almost the same efficiency for removing PM as the DPF but had significantly improved (75%∼90% lower) differential pressure drops.  相似文献   
176.
A fault detection method with parity equations is proposed in this paper. Due to its low cost implementation, the velocity of the motor is not measurable in electric parking brake (EPB) systems. Therefore, residuals are not reliable when estimating the motor velocity with a low-resolution encoder. In this paper, we propose a fault detection method with sensorless estimation using current ripples that estimates the position and velocity of the motor by detecting periodical oscillations of the armature current caused by rotor slots. In addition, this method can estimate the position and velocity of the motor with less computational effort than a state observer. Moreover, the method is less sensitive to motor parameters than model-based estimation methods. The effectiveness of this method is validated with experimental data, and the simulation results show that various faults have their own residual patterns. Therefore, we can detect the presence of faults by monitoring the residual signals.  相似文献   
177.
This paper describes the on-line debugging software developed by our research team. The software has five functions and can be helpful in achieving rapid development for hybrid electric buses. In addition, the software can monitor system states continuously and also modify parametric maps or update control programs using its on-line programming function. Based on the on-line debugging system, the hybrid propulsion control system is designed, and all the working modes of the hybrid electric bus are tested. Finally, experiments are carried out that verify that the debugging system is feasible and reliable. The test results show that the hybrid electric bus can reduce fuel consumption by about 19.1 percent, in comparison with conventional buses.  相似文献   
178.
The power split type hybrid system transmits engine power by dividing it into the electrical unit and the mechanical unit. Its power transmission efficiency is highest at the mechanical point (MP), where the full power is transmitted to the mechanical unit. In this study, the equation for the MP was derived for the gear ratios of a general 4-node lever model. The MP characteristics for the transmission ratio (TR) of the input split and compound split structures were examined using the equation derived. Using the examined input split and compound split structures, a systematic design method for the dual mode power split transmission was proposed. In the dual mode power split transmission, the MP could be positioned at the desired TR, and the input split and compound split modes could be selectively used according to the clutch combination, which leads to the operation of the vehicle within a high system efficiency range.  相似文献   
179.
We investigated the effects of injection parameters such as injection pressure, ambient pressure, and ambient temperature on spray characteristics. We calculated the turbulence occurring point (t c ), defined as the time required to generate a vortex, and the deceleration point (t b ), defined as the time when spray penetration begins to decelerate, to elucidate the breakup mechanism of the test injectors. The spray velocity coefficient (Cv) was obtained to evaluate the spray characteristics. As the ambient pressure increases in the case of a slit injector, Cv decreases. We investigated the effects of nozzle tip shape according to injection pressure, ambient pressure, and fuel properties on spray characteristics and provide a Cv value of 0.38 for the swirl injector with a spray angle of 60° and the slit injector under atmospheric conditions. The value of Cv in the case of a slit injector was reduced by increasing the ambient pressure. Our results suggest that Cv of a swirl injector is constant regardless of changes in ambient pressure, injection pressure, and fuel properties. On the other hand, Cv of a slit injector is altered by changes in ambient pressure.  相似文献   
180.
An electronic throttle consists of a DC motor, spur gears, a return spring, a position sensor, power electronics and an electronic control unit. Fast and precise position control of this electromechanical system is relatively difficult due to very high friction and the strong nonlinearity of the spring. Simple application of linear control, such as PID, fails. In this paper, two new controller structures suitable for different reference signal types are described. The key component of the position controller is the friction compensator based on either/both feedforward or feedback principles. The quality of the resulting behavior was measured using several criteria including the measure of control activity around the equilibrium position. The control activity directly influences the vibration, the noise and the wear of the servo system. The proposed controllers demonstrated superior behavior compared with other published structures.  相似文献   
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