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961.
[1]结构噪声核心价值与理论逻辑解读第三部分:WPA法与机理分析…吴崇建,雷智洋,吴有生(1)[2]搁置脚载荷作用下的甲板压力分布特征实验和数值分析…熊群飞,徐志亭,王福花,王德禹(10)[3]船用钢板高频感应加热热源简化计算方法…张正星,赵耀,胡小才,杨振(18)[4]载运履带式车辆装备的船舶局部强度校核…陈益平,张勇(25)[5]水下爆炸下舰艇不同部位冲击环境数值分析…董九亭,刘建湖,汪俊,刘国振(32)[6]推力轴承基座结构形式对潜艇振动噪声的影响…孙谦,刘文玺,周其斗,纪刚(39)[7]基于统计能量法研究肋骨对双层圆柱壳声辐射特性的影响…张恺,纪刚,周其斗,李宗威(46)[8]阻尼材料粘贴面积灵敏度分析…徐建龙,彭利国,潘国雄,魏笔(53)[9]多点锚泊定位系统布锚夹角的影响及优化分析…韩森,贾宝柱,孙文正,顾一鸣(61)[10]舵空化的精细流场及其非定常水动力性能数值计算…于安斌,叶金铭,王友乾(68)[11]参数化单元边界元法解势流速度场问题…刘梦超,刘延俊,薛钢,吴瀚崚(77)[12]舰船动力系统排烟对甲板上方空间温度场影响的数值分析…张佳佳,付云鹏,叶正华,孙鹏,钟兢军,杨木肖(85)[13]机舱区域人员疏散仿真分析…叶正华,黄志刚,蒲晓亮(91)[14]星型空压机曲柄连杆机构动力学特性分析…李超博,楼京俊,吴海平,石迎潮(97)[15]水润滑橡胶轴承摩擦振动特征分析…彭伟才,谈宇航(103)[16]基于NESO的潜艇航向滑模控制器设计…陆斌杰,李文魁,陈尔明(108)[17]通过式消磁站线圈系统仿真设计…周炜昶,郭成豹(114)[18]基于优势度测量的舰船电子信息系统方案优选…曲全福,李金鹏(121)[19]基于反潜探测能力的舰队搜潜队形优化研究…张诗,闵绍荣,朱忍胜,余明晖,高艺哲(126)[20]基于改进禁忌搜索算法的舰载机保障作业调度…李梦龙,余明晖(132)[21]基于离散蝙蝠算法的舰船作战系统测试性分析…范苗,许一川,谢定君,彭辉(139)  相似文献   
962.
[1]水下接触爆炸下多舱防护结构载荷特性及动响应研究进展…吴庭翱,张弩,侯海量,吴国民,周心桃(1)[2]水下接触爆炸作用下泡沫夹芯板耗能机理研究…赵延杰,郝轶,刘建湖,张攀(13)[3]飞片撞击冲击波载荷在液舱中的弥散效应…赵延杰,汪俊,郝轶,张伦平,刘建湖(23)[4]舷侧防护结构抗导弹动能穿甲防护性能数值仿真…叶帆,刘见华,王福花(32)[5]舱内爆炸载荷下箱型梁船体节点结构强度分析…张弩,刘均,李凯,李德聪(39)[6]耐压抗冲覆盖层在水下爆炸载荷作用下的冲击防护特性…殷彩玉,金泽宇,谌勇,华宏星(46)[7]极间弹体偏转电磁力的影响因素仿真研究…陈恩涛,刘建湖,张显丕,张伦平(53)[8]200 t级浮动冲击平台水下爆炸试验低频冲击响应数据分析…张磊,杜志鹏,吴静波,计晨,张春辉,冯麟涵(60)[9]水下爆炸气泡对舰船冲击环境的影响…曾令玉,蔡尚,王诗平(66)[10]敷设橡胶圆板近场水下爆炸数值模拟…金泽宇,殷彩玉,谌勇,华宏星(72)[11]空爆载荷下功能梯度泡沫铝夹层板动响应数值仿真…李春鹏,张攀,刘均,程远胜(77)[12]基于时域分析的设备抗冲击连接件简化方法…李海涛,刘建湖,何斌,王海坤,裴度(85)[13]舰艇气瓶基座结构抗冲击性能评估方法…郭君,孙占忠,黄式璋,李晓文(90)[14]空腔结构入水冲击加速度和压力响应试验仿真分析…张岳青,庞多,蔡卫军,李建辰(97)[15]实尺度舰船舱内炮弹静爆试验方法…杜志鹏,张磊,赵鹏铎(103)[16]尖头弹侵彻金属板花瓣型破口成形过程仿真分析…伍星星,刘建湖,张伦平,孟利平,汪俊(110)[17]基于物质点法的弹体侵彻靶板破甲特性数值模拟…秦业志,姚熊亮,王志凯,王莹(118)[18]基于典型舰船结构特征的陆地靶标设计方案…吴子奇,徐振桓,王志凯,王治,姚熊亮(125)[19]反舰导弹战斗部近距空爆的毁伤威胁性分析…赵传,王树山,马瑾,谭朝明(131)[20]舰船舱内爆炸载荷特征与板架毁伤规律分析…姚熊亮,屈子悦,姜子飞,王志凯,王治(140)[21]改进的3阶WENO-N3格式及其在内爆炸载荷计算中的应用…徐维铮,吴卫国(149)  相似文献   
963.
[1] 喷水推进和泵喷推进的概念:共性、特性及区别…王永生(1)[2] 船舶推进轴系方案设计的关键技术研究进展…赖国军,刘金林,雷俊松,夏极,周瑞平,曾凡明(10)[3] 基于交互式赋权与证据推理的船舶主机优选…赵瑞嘉,谢新连,赵家保,王郅翔(22)[4] 锌镍单液流电池二维瞬态放电模型…姚寿广,赵倩,赵云辉,孙晓飞,程杰(28)[5] 柴油机舷侧排气喷淋流动及传热模拟…王振,吴炜,杨先勇,安一峰,刘元春(36)[6] 多光谱反演火焰温度及烟黑体积分数研究…章奇,司梦婷,王东旭,王安振,李灿,王振,罗自学,娄春,程强(42)[7] 船舶推进轴系弯—纵耦合效应的非线性振动特性…徐鹏,邹冬林,吕芳蕊,塔娜,饶柱石(49)[8] 饱和含液穿孔板条水润滑艉轴承减振性能研究…金勇,邝俊信,田相玉,劳坤胜,欧阳武,刘正林(58)[9] 水下航行体推进轴系多状态下的变形特征分析…余桐泉,李天匀,刘圣超,朱翔(64)[10] 基于体积力的海水自流循环系统流速确定方法…陈康,姚志崇,周恩东,夏彬(70)[11] 某船用柴油机排气管路流动分析及均匀性评估…李本钶,黄冰阳,李艳华,聂富成,叶晓明(77)[12] 潜艇通气管进气阀阻力特性分析及优化…胡海滨,周睿,周哲,刘义军(85)[13] 深海爬游机器人多腿位姿对巡游稳定性的影响…张康,王磊,冷文军,陈虹(90)[14] 水炮系统添加剂减阻分析及方案设想…林芃,高一民,蔡伟华,陈轶君,陈红超(98)[15] 水平开口有限空间油池火燃烧特性分析…陈兵,张世奇,时训先,黎昌海,陆守香(106)[16] 机械排烟时补风口高度对竖直单开口舱室火灾烟气特性的影响…邱金水,任广鲁,刘伯运,陈如木(112)[17] 邻近雷击电场环境模拟装置的设计与实现…王可,段艳涛,石立华,黄瑞涛,陈海林(119)[18] 密闭空间内爆炸准静态压力理论计算研究…徐维铮,吴卫国(124)[19] 基于波动理论的共振转换器减振特性分析…李良伟,赵耀(131)[20] 基于动柔度方法的管路动力吸振器设计研究…张琳,李华峰,陈勇,张涛,丁杨建(138)[21] 基于整数线性规划方法的舰载机航空保障资源优化调度…谭大力,王云飞,于连飞,朱承(145)[22] 基于视觉测量的舰载机空间定位方法…刘佳铭(152)[23] 罗经方位对准的收敛时间分析…何东旭,葛磊,张鑫,臧新乐(159)  相似文献   
964.
In 2009, the US government spent more than $42 billion on the federal-aid highway program. Most of this money was raised from motor vehicle taxes, whose proceeds are deposited in the highway trust fund. Federal motor vehicle user taxes flow into the fund and aid expenditures flow out from it to build and maintain highways and other transportation infrastructure. With so much money at stake it should be no surprise that expenditure decisions are the subject of intense political debate. Chief among these debates is the conflict between donor states, whose residents pay more in highway user taxes than the state receives in federal highway aid and donee states, whose residents pay less in highway user taxes than the state receives in highway aid. While this geographic redistribution has been masked recently by infusions of general fund revenue into the trust fund, the debate nevertheless continues. This paper attempts to understand why some states are donors and others are donees by simultaneously testing four hypotheses about the geographic redistribution of federal highway dollars that relate to a state’s highway need, economic condition, level of urbanization, and representation on the key Congressional oversight committees. The analyses show that redistribution does not favor states with larger highway systems, more highway use, or lower median incomes, all of which are different indicators of need. Instead, states that are less urban and better represented on the four key Congressional committees generally benefit from redistribution. These findings indicate that the user tax revenues are not used in places where they are most needed. Thus they provide little empirical support for any compelling policy argument for continued geographic redistribution of federal highway user tax dollars.  相似文献   
965.
R. J. Allport 《运输评论》2013,33(4):365-384
This paper is concerned with the majority of developing nations who lack large resources for public sector projects. It questions the basis of much mass transit planning and attempts to put forward a more efficient way of reaching decisions. It calls extensively on experience of Metro Manila, capital of the Philippines, where an innovative system of metropolitan planning and administration is throwing a new light on ‘appropriate’ investment in such developing cities.

Mass transit systems as currently conceived in such developing cities—fully segregated rail‐based systems—are unlikely to be affordable (at least for many years) and in consequence scarce resources should not be devoted to developing and evaluating them. Rather, the principal objective should be to provide low‐cost, affordable mass transit—affordable to governments and to passengers. This almost certainly points to road‐based systems, or predominantly at‐grade light rail transit (LRT) systems, which are usually regarded as ‘obviously unworkable’ in developing city environments.

This judgement is questioned and it is suggested the potential of LRT to provide appropriate low‐cost mass transit is not being realized. An approach to determining its potential applicability is proposed. If feasible it should be evaluated against road‐based systems before decisions to implement new mass transit systems are taken.

While circumstances vary between countries the central message of this paper—that public sector resources have a very high opportunity cost which make all but the lowest‐cost mass transit systems very difficult to justify—will hold in all but the higher‐income developing economies.  相似文献   
966.
This paper considers the problem of freeway incident detection within the general framework of computer‐based freeway surveillance and control. A new approach to the detection of freeway traffic incidents is presented based on a discrete‐time stochastic model of the form ARIMA (0, 1, 3) that describes the dynamics of traffic occupancy observations. This approach utilizes real‐time estimates of the variability in traffic occupancies as detection thresholds, thus eliminating the need for threshold calibration and lessening the problem of false‐alarms. Because the moving average parameters of the ARIMA (0, 1, 3) model change over time, these parameters can be updated occasionally. The performance of the developed detection algorithm has been evaluated in terms of detection rate, false‐alarm rate, and average time‐lag to detection, using a total of 1692 minutes of occupancy observations recorded during 50 representative traffic incidents.  相似文献   
967.
In this paper, the application of a model representing the impact of interaction between transport costs and the location of housing, population, job employment, shopping and land is described. Two particular uses of the model are considered. Firstly, the effects of changing transport costs upon people of different social status in terms of money and time spent on travelling are examined and compared with results based upon the assumption that the location of population and employment are not responsive to changes in transport cost, as in the conventional transport demand model. Secondly, the effects of six land use‐transport policy sets are examined in terms of the impact upon urban morphology, and the opportunities and travel behaviour of the three social groups. The effects are also compared with the objectives of the strategies.  相似文献   
968.
This paper presents the development and assessment of models to estimate pedestrian demand based on the level of pedestrian activity (high and low). As activity varies by the time of the day, temporal variations were evaluated by considering different time periods. Data collected at 128 low and 48 high pedestrian activity signalized intersections (a total of 176 signalized intersections) in the City of Charlotte, North Carolina were used to develop and assess the models using stepwise regression analysis through backward elimination of independent variables (includes demographic, land use, and network characteristics). The use of different buffer widths (proximal area) to extract these characteristics was also evaluated. Results, in general, show that pedestrian demand varied by the level of activity, explanatory variables extracted by buffer width, and time of the day. The estimates from the models could be used in transportation planning (identify required pedestrian facilities, resource allocation), safety, and operational analyses. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
969.
According to the Belgrade Master Plan for 2021, the public transportation system for the city and its region will include three rail modes: a modernized existing tramway, regional rail, and a new light rail transit (LRT) mode. In the coming years all three rail modes should be developed simultaneously and in a coordinated manner. The introduction of LRT is to be realized in several phases, and its first line will partially follow the alignment of an existing tramway line. As the present tramway vehicles are obsolete, new rolling stock must be designed and purchased to be compatible with many of the elements of the LRT. Ways to adjust the new tramways to the LRT rolling stock represent the central topic of this paper. The basic technical and operating characteristics of the new tramway are defined with respect to their required compatibility with the LRT stock and infrastructure.  相似文献   
970.
There is little information in the literature on the relation between rural speed and safety. The wide variation in rural speed limits that are applied in different countries tends to confirm that this relation is poorly understood. The changes in fatal, injury and all accidents that followed a change in the rural speed limit in seven countries were regressed against the change in vehicle mean speed. The results showed that speed significantly affects safety and that within certain limits the relation is linear. The regressions indicated that a 1 km/h reduction in speed will reduce all severities of accidents by between 4 and 5%. It is suggested that part of this reduction is due to a change in economic factors.  相似文献   
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