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321.
Mei-Ting Tsai Chih-Peng Chu 《Transportation Research Part D: Transport and Environment》2012,17(2):145-148
This paper investigates a parking reservation mechanism to reduce car cruising to find parking. To consider the benefits for drivers and parking facility providers, we charge drivers for making reservations in addition to parking fees, by introducing a reservation pricing model that makes reservation prices equivalent to the value of saved search time. By modeling the number of vacant spaces as a stochastic variable, and applying binomial pricing methods, parking reservation prices are obtained. Numerical examples based on the data for two parking facilities in Taiwan are given. 相似文献
322.
Singfat Chu 《Transportation Research Part A: Policy and Practice》2012,46(10):1541-1550
Permit or license plate quotas are highly effective albeit controversial policy tools for managing growth in the vehicle population and thereby, adverse traffic congestion. A judicious distribution of the scarce permits that targets the dual objectives of price efficiency and social diversity in vehicle ownership can however mitigate the controversy. This paper scrutinizes the attainment levels of these two objectives within Singapore’s multi-categorical Vehicle Quota System in two time periods (1991–1998 and 2002–2011) which differ in the number of permit allocation categories, the auction format used (sealed versus open bids) and in the frequency of distribution (monthly versus semimonthly). The lessons derived are contrasted to the other two jurisdictions which have also implemented quotas on their vehicle registrations namely, Shanghai and Beijing. 相似文献
323.
This study looks at the degrees of interference for multiple cranes that work simultaneously at six major container terminals in the port of Kaohsiung. The results confirm that there are different degrees of mutual crane interference among terminals where different operational modes are adapted in the container yards. RTG handling systems show a very high value of aggregate cranes exponent f, with nearly no interference, as long as the number of allocated cranes is no more than the number of truck lanes under each crane. While SC systems reveal a relatively larger degree of mutual interference as the number of cranes increase. 相似文献
324.
Intestinal infection is a major type of traumat-ic infections[lj. Intestinal dysbacteriosis is one ofreasons which cause the translocation of intestinalconditioned pathogen and endotoxin, and subse-quently intestinal infectionL2j. To correct dysbacte-riosis quickly and to recover intestinal micro--e-cosystem are important ways in the control of trau-matic infection. Synbiotics and probiotics are regu-lators of intestinal micro--ecosystem['3,no report ontheir use for the treatment of intestinal… 相似文献
325.
目的 将具有全长血小板生成素 (TPO)活性的N端截短血小板生成素cDNA(T1 84)作为目的基因 ,在中华仓鼠卵巢细胞 (CHO)中成功表达。方法 将N端截短血小板生成素cDNA克隆入以二氢叶酸还原酶 (DHFR)为筛选扩增基因的 pDC B真核表达载体 ,通过不断提高MTX浓度 ,促进N端截短血小板生成素在CHO细胞中的表达。结果 构建了N端截短血小板生成素cDNA的真核表达质粒 ,并能在CHO细胞中高效表达。结论 N端截短血小板生成素cDNA在CHO细胞中成功表达 ,其产物具有全长TPO的活性。 相似文献
326.
空泡水筒中螺旋桨模型试验的筒壁影响和修正 总被引:1,自引:0,他引:1
在中国船舶科学研究中心工作段直径为0.8米的水筒中,试验了三个几何相似的螺旋桨模型。用激光测速仪测量了螺旋桨前后不同截面的水筒流速分布,也测量了筒壁上的压力分布。对水筒中进行无空泡、有空泡和超空泡螺旋桨试验时,应如何进行筒壁影响的修正,提供了依据。同时还指出,水筒中螺旋桨的推力或负荷系数与水池敞水试验值相同时,其流场仍然是不同的。 相似文献
327.
Vijay K. Garg Yun Lung Wang Kuang-Han Chu 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1984,13(2):73-92
The dynamic performance of a flat car is studied herein. The performance indices include roll angles, lateral accelerations, center plate loads, side bearing loads, wheel loads and spring deflections. These variables are maximum when the car is running at its critical speed, corresponding to either the rock and roll, or the bounce mode. The Association of American Railroads' (AAR) Flexible Carbody Model was used. The input for vertical track irregularities used in the simulation was generated from published spectra for U.S. Federal Railroad Administration (FRA) Class 4 track. After studying the car's performance with various column loads and spring suspensions, it was found that the most commonly used column load of 4,000 lbs. (17.8 kN) should be used. The spring suspension used in the original car design should also be adopted, in order to avoid spring. bottoming. 相似文献
328.
坐落于软土地基上的斜坡式防波堤结构会产生较大的地基沉降,通过物理模型试验研究在软土地基上地基沉降量较大的情况下,斜坡式防波堤堤身和护面块体的稳定性.试验结果表明,较大的地基沉降量对斜坡堤堤身和护面块体稳定的影响有限. 相似文献
329.
用力学分析的方法,解决船舶非单点搁浅时船底受力大小及脱浅拖力最小值的计算方法问题,并由此提出船舶自行脱浅的两种方法。 相似文献
330.