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991.
992.
Attitudes towards public transport (PT) in New Zealand’s three largest cities (Auckland, Wellington, and Christchurch) were
examined in a cross-sectional survey of drivers. A measure of prejudice to PT was developed to assess the strength and nature
of attitudinal differences. Auckland residents had the highest levels of PT prejudice while Wellington residents had the lowest,
and these differences were not related to demographic differences between the samples. Direct contact with PT was associated
with reduced levels of PT prejudice, but measures of indirect contact, beliefs about using PT, and environmental attitudes
were stronger predictors of PT prejudice scores. Controlling for these variables resulted in the difference in PT prejudice
levels between Wellington and Christchurch becoming non-significant, while the differences between Auckland and the other
two cities remained. This suggests that the difference between Wellington and Christchurch was primarily based on social norms
regarding PT prejudice, while quality of service was a factor in the difference between Auckland and the other two cities.
It is suggested that campaigns promoting PT ridership should focus both on the quality of service and on presenting PT usage
as socially normal. 相似文献
993.
In order to study the influence of wind mixing on the spring variability of the plankton production of the north western Corsican coastal area, a one-dimensional (1D), vertical, coupled hydrodynamic/biological model (ECOHYDROMV) is used. A hydrodynamic 1D model of the water column with a k–l turbulent closure is applied. The biological model comprises six state variables, representing the plankton ecosystem in the spring period: phytoplankton, copepods, nitrate, ammonium, particulate organic matter of phytoplanktonic origin and particulate organic matter of zooplanktonic origin. The system is influenced by turbulence (expressed by the vertical eddy diffusivity), temperature and irradiance. The model takes into account momentum and heat surface fluxes computed from meteorological data in order to simulate a typical spring atmospheric forcing for the considered area. Results show that primary production vertical structure is characterised by a subsurface maximum which deepens with time and is regulated by the opposite gradients of nitrate concentration and irradiance. Surface plankton productivity is mainly controlled by turbulent vertical transport of nutrients into the mixed layer. The short time scale variability of turbulent mixing generated by the wind appears to be responsible for the plurimodal shape of plankton blooms, observed in the considered area. Furthermore, the model is applied to the study of the spring evolution of the plankton communities off the bay of Calvi (Corsica) for the years 1986 and 1988. In order to initiate and validate the model, time series of hydrological, chemical and biological data have been used. The model reproduces accurately the spring evolution of the phytoplankton biomass measured in situ and illustrates that its strong variability in those years was in close relation to the variability of the wind intensity. 相似文献
994.
Bonnet weight reduction and VRU protection: Design proposals implementing non-conventional materials
G. Belingardi G. Chiandussi E. Gobetto A. Scattina 《International Journal of Automotive Technology》2010,11(6):831-842
The use of non-conventional and innovative materials is increasingly important in automotive design. They allow reductions
in the weights of structures with consequent reductions in fuel consumption and carbon dioxide emissions. At the same time,
they ensure excellent safety levels. Once excellent results in terms of active and passive safety have been obtained, the
attention of car manufacturers, and of the public opinion, is focused on the safety of vulnerable road users (VRU), pedestrians
and cyclists. Some examples concerning the redesign of a bonnet with the double targets of weight reduction and pedestrian
safety are illustrated. Hybrid metal/plastic and more conventional metal sheet solutions are compared. The static performance
(stiffness and denting resistance), as well as the impact against a pedestrian head, are evaluated by means of FEM models
along with actual regulations. 相似文献
995.
T. H. S. Li C. J. Huang C. C. Chen 《International Journal of Automotive Technology》2010,11(4):581-592
A novel tracking and almost disturbance decoupling problem of multi-input, multi-output (MIMO) nonlinear systems based on
feedback linearization and a multi-layered feedforward neural network approach has been proposed. The feedback linearization
and neural network controller guarantees exponentially global uniform ultimate bounded stability and almost disturbance decoupling
performance without using any learning or adaptive algorithms. The new approach renders the system to be stable with the almost
disturbance decoupling property at each step when selecting weights to enhance the performance if the proposed sufficient
conditions are maintained. One example, which cannot be solved by the existing approach of the almost disturbance decoupling
problem because it requires the sufficient conditions that the nonlinearities that multiply the disturbances satisfy structural
triangular conditions, is proposed to exploit the fact that the tracking and the almost disturbance decoupling performances
are easily achieved by the proposed approach. In order to demonstrate the practical applicability, a famous half-car active
suspension system is investigated. 相似文献
996.
现代化有轨电车系统在中国城市的发展前景 总被引:1,自引:0,他引:1
为什么在中国城市发展现代化有轨电车系统呢?这种交通方式有哪些优点和不足之处呢?通过对现代化有轨电车系统的主要特点的阐述,充分显示了现代有轨电车系统满足中国城市交通需求的独特魅力。 相似文献
997.
S. S. Merola P. Sementa C. Tornatore 《International Journal of Automotive Technology》2011,12(1):93-101
In this paper, flame front propagation during normal and abnormal combustion was investigated. Cycle-resolved flame emission
imaging was applied in the combustion chamber of a port fuel injection-boosted spark ignition engine. The engine was fueled
with a mixture of 90% iso-octane and 10% n-heptane by volume (Primary Reference Fuel 90: PRF90) and commercial gasoline. The
combustion process was monitored from the flame kernel formation until the exhaust valves opened. Different phenomena associated
with abnormal combustion were analyzed, including the fuel deposition burning. Moreover, the ignition surfaces and end-gas
auto-ignitions were investigated in terms of timing, location and frequency of occurrence. The analysis was performed by considering
different knocking intensities for both the selected fuels. 相似文献
998.
999.
This paper builds up a typical model of a parallel hybrid electric vehicle and develops model predictive controllers for this
model to control the speeds and torques for fast clutch engagement with high driving comfort and low jerk. Some modified algorithms
for model predictive controllers are studied to improve their ability to track the desired speed setpoints, subject to input
and output constraints. 相似文献
1000.
H.N. Li C.K. Chau M.S. Tse S.K. Tang 《Transportation Research Part D: Transport and Environment》2009,14(4):264-271
This study estimates the willingness-to-pay value for a one dB(A) change over a range of initial noise levels for a sample population in Hong Kong. It establishes a protocol for estimating the willingness-to-pay values by first establishing an annoyance–dB relationship. The protocol takes into account the characteristics that the probability of being annoyed at a particular level varied with the initial objective noise level, and the annoyance–dB relationship varied for a range of initial annoyance level. The study shows that household income level and initial annoyance levels exert considerable influences on the individual’s willingness-to-pay values. However, age and educational level were found not to exert any significant influence on individual’s willingness-to-pay values. 相似文献