全文获取类型
收费全文 | 480篇 |
免费 | 3篇 |
专业分类
公路运输 | 282篇 |
综合类 | 13篇 |
水路运输 | 106篇 |
铁路运输 | 2篇 |
综合运输 | 80篇 |
出版年
2021年 | 2篇 |
2020年 | 2篇 |
2019年 | 4篇 |
2018年 | 28篇 |
2017年 | 36篇 |
2016年 | 25篇 |
2015年 | 6篇 |
2014年 | 39篇 |
2013年 | 57篇 |
2012年 | 38篇 |
2011年 | 46篇 |
2010年 | 36篇 |
2009年 | 52篇 |
2008年 | 38篇 |
2007年 | 4篇 |
2006年 | 9篇 |
2005年 | 7篇 |
2004年 | 5篇 |
2003年 | 9篇 |
2002年 | 5篇 |
2001年 | 2篇 |
2000年 | 5篇 |
1999年 | 5篇 |
1998年 | 3篇 |
1997年 | 5篇 |
1996年 | 2篇 |
1995年 | 4篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1988年 | 1篇 |
1976年 | 1篇 |
1973年 | 4篇 |
排序方式: 共有483条查询结果,搜索用时 15 毫秒
481.
J. Hwang D. Lee K. Huh H. Na H. Kang 《International Journal of Automotive Technology》2011,12(1):119-124
The longitudinal and lateral vehicle control techniques have been widely used in several active driver assistance systems.
The adaptive cruise control, lane keeping assistant control, vehicle platooning and stop-and-go control are typical examples
of the most important applications. In this study, a novel path planning method is proposed considering the driving environment
such as road shape, ego vehicle and surrounding vehicles’ movement. The relative distance and velocity between the ego vehicle
and surrounding vehicles are identified with respect to the predicted lane shape in front of the ego vehicle. Based on the
identified information, the road shape and surrounding vehicles are mapped into the intensity image and the desired vector
for the ego vehicle’s movement is determined by the maximum intensity density tracing method. The desired vehicle path is
followed by the acceleration/deceleration control and the steering assist control, respectively. In order to evaluate the
performance of the proposed system, simulations are conducted and compared with ACC systems. 相似文献
482.
Sahbi Khanfir Kazuhiko Hasegawa Vishwanath Nagarajan Kouichi Shouji Seung Keon Lee 《Journal of Marine Science and Technology》2011,16(4):472-490
With a recent increase in ship capacity and propulsion performance, a wide-beam ship fitted with a twin-rudder system has
been adopted in many cases. However, to improve ship manoeuvring, it is still necessary to have a better understanding of
rudder-hull interactions in twin-rudder ships. Captive model tests (oblique towing and circular motion test) as well as free-running
tests with a single-propeller twin-rudder ship and a twin-propeller twin-rudder ship are carried out. The effect of drift
angle on the rudder forces and some peculiar phenomena concerning rudder normal force for twin-rudder ships are evaluated.
A method for estimating the hull-rudder interaction coefficients based on free-running experimental results is proposed. 相似文献
483.
From suspended particles to strata: The fate of terrestrial substances in the Gaoping (Kaoping) submarine canyon 总被引:1,自引:0,他引:1
James T. Liu Jia-Jang Hung Hui-Ling Lin Chih-An Huh Chon-Lin Lee Ray T. Hsu Ya-Wen Huang Joel C. Chu 《Journal of Marine Systems》2009,76(4):417
The river–sea system consisting of the Gaoping (new spelling according to the latest government's directive, formerly spelled Kaoping) River (KPR), shelf, and Submarine Canyon (KPRSC) located off southern Taiwan is an ideal natural laboratory to study the source, pathway, transport, and fate of terrestrial substances. In 2004 during the flood season of the KPR, a system-wide comprehensive field experiment was conducted to investigate particle dynamics from a source-to-sink perspective in the KPRSC with the emphasis on the effect of particle size on the transport, settling, and sedimentation along the pathway. This paper reports the findings from (1) two sediment trap moorings each configured with a Technicap PPS 3/3 sediment trap, and an acoustic current meter (Aquadopp); (2) concurrent hydrographic profiling and water sampling was conducted over 8 h next to the sediment trap moorings; and (3) box-coring in the head region of the submarine canyon near the mooring sites. Particle samples from sediment traps were analyzed for mass fluxes, grain-size composition, total organic carbon (TOC) and nitrogen (TN), organic matter (OM), carbonate, biogenic opal, polycyclic aromatic hydrocarbon (PAH), lithogenic silica and aluminum, and foraminiferal abundance. Samples from box cores were analyzed for grain-size distribution, TOC, particulate organic matter (POM), carbonate, biogenic opal, water content, and 210Pbex. Water samples were filtered through 500, 250, 63, 10 µm sieves and 0.4 µm filter for the suspended sediment concentration of different size-classes.Results show that the river and shelf do not supply all the suspended particles near the canyon floor. The estimated mass flux near the canyon floor exceeds 800 g/m2/day, whose values are 2–7 times higher than those at the upper rim of the canyon. Most of the suspended particles in the canyon are fine-grained (finer than medium silt) lithogenic sediments whose percentages are 90.2% at the upper rim and 93.6% in the deeper part of the canyon.As suspended particles settle through the canyon, their size-composition shows a downward fining trend. The average percentage of clay-to-fine-silt particles (0.4–10 µm) in the water samples increases from 22.7% above the upper rim of the canyon to 56.0% near the bottom of the canyon. Conversely, the average percentage of the sand-sized (> 63 µm) suspended particles decreases downward from 32.0% above the canyon to 12.0% in the deeper part of the canyon. Correspondingly, the substrate of the canyon is composed largely of hemipelagic lithogenic mud. Parallel to this downward fining trend is the downward decrease of concentrations of suspended nonlithogenic substances such as TOC and PAH, despite of their affinity to fine-grained particles.On the surface of the canyon, down-core variables (grain size, 210Pbex activity, TOC, water content) near the head region of the canyon show post-depositional disturbances such as hyperpycnite and turbiditic deposits. These deposits point to the occurrences of erosion and deposition related to high-density flows such as turbidity currents, which might be an important process in submarine canyon sedimentation. 相似文献