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961.
Construction of eukaryotic recombinant vector of renalase and its expression as a eukaryotic protein
Renalase is a secreted amine oxidase that metabolizes catecholamines. It has been proposed to modulate blood pressure and
heart rate and its downregulation might result in hypertension. Despite its potential relevance for human health, the biochemical
characterization of renalase is still scarce. The aim of this study is to synthesize the human renalase eukaryotic protein
by genetic engineering. The human renalase gene was amplified by polymerase chian reaction (PCR). After digestion by BamH
I and Xho I enzymes, the DNA fragments were cloned into the transfer vector, pFastBacHTb-Fc, to generate the pFastBacHTb-renalase
expression vector. The ligation products were transformed into E. coli DH10Bac to obtain recombinant transposon rBacmid-renalase. The recombinant transposon was further transferred into insect
high-V cells, and the recombinant human renalase eukaryotic protein was expressed successfully. 相似文献
962.
Guoyan Cao John Michelini Karolos Grigoriadis Behrouz Ebrahimi Matthew A. Franchek 《智能交通系统杂志
》2016,20(6):516-531
》2016,20(6):516-531
In this article, a systematic strategy is proposed to identify severe driving events occurrence correlation with time and location. The proposed approach, which is constructed based on batch clustering and real-time clustering techniques, incorporates historical and real-time data to predict the time and location of severe driving events. Batch clustering is implemented with the combination of subtractive clustering and fuzzy c-means clustering to generate clusters representing the initial correlation patterns. Real-time clustering is then developed to create and update real-time correlation patterns on the foundation of the batch clustering using the evolving Gustafson–Kessel like (eGKL) algorithm. In both clustering processes, the correlation of the events within time domain is identified first, and then two different levels of accurate correlations are conducted for the location domain. Real-time data of operating vehicles each equipped with a data acquisition and wireless communication platform are used to validate the proposed strategy. Batch clustering results reveal the severe braking events distribution and concentration at daytime and nighttime. Real-time clustering provides and updates the variation of the correlations/intercorrelation of different regions. Drivers can be notified of the potential severe driving locations through maps showing the driving routes. Through the variation of the correlations, drivers can recognize the events occurrence at different times and locations. The generated time series can be potentially used to develop spatial-time models for regions to model and forecast the events occurrence. 相似文献
963.
Abstract The use of fossil fuels in transportation is an important topic as a result of growing concerns over global warming. Automobile petrol demand has been of particular interest to researchers and policy-makers, given that the automobile is a major contributor to the enhanced greenhouse effect. This paper forecasts Australia's automobile petrol demand up to the year 2020 based on the best performing forecasting model selected out of eight models. In order to establish ways to reduce the demand for petrol, and the consequent by-product of reducing the amount of greenhouse gas emissions, we have estimated the impact on CO2 for several potential policy instruments, using Transportation and Environment Strategy Impact Simulator (an integrated transport, land use and environmental strategy impact simulation programme). We find that a carbon tax of AU$0.50/kg can reduce automobile kilometres by 5.9%, resulting in reduced demand for petrol and a reduction in CO2 of 1.5%. 相似文献
964.
Zheng Li John M. Rose David A. Hensher 《Transportation Research Part A: Policy and Practice》2010,44(1):16-38
Transport fuel consumption and its determinants have received a great deal of attention since the early 1970s. In the literature, different types of modelling methods have been used to estimate petrol demand, each having methodological strengths and weaknesses. This paper is motivated by an ongoing need to review the effectiveness of empirical fuel demand forecasting models, with a focus on theoretical as well as practical considerations in the model-building processes of different model forms. We consider a linear trend model, a quadratic trend model, an exponential trend model, a single exponential smoothing model, Holt’s linear model, Holt–Winters’ model, a partial adjustment model (PAM), and an autoregressive integrated moving average (ARIMA) model. More importantly, the study identifies the difference between forecasts and actual observations of petrol demand in order to identify forecasting accuracy. Given the identified best-forecasting model, Australia’s automobile petrol demand from 2007 through to 2020 is presented under the “business-as-usual” scenario. 相似文献
965.
966.
Hydraulic butterfly valves have been widely applied in marine engineering because of their large switching torque, low pressure
loss and suitability for large and medium diameter pipelines. Due to control problems resulting from switching angular speeds
of the hydraulic butterfly valve, a throttle-governing control mode has been widely adopted, and detailed analysis has been
carried out worldwide on the structural principle concerning speed-regulation and the load torque on the shaft while opening
or closing a hydraulic butterfly valve. However relevant reports have yet been published on the change law, the error and
the influencing factors of the rotational angular velocity of the hydraulic butterfly valve while opening and closing. In
this article, research was based on some common specifications of a hydraulic butterfly valve with a symmetrical valve flap
existing in a marine environment. The throttle governing system supplied by the accumulator to achieve the switching of the
hydraulic control valve was adopted, and the mathematical models of the system were established in the actual conditions while
the numerical simulations took place. The simulation results and analysis show that the rotational angular velocity and the
error of the hydraulic butterfly valve while switching is influenced greatly by the drainage amount of the accumulator, resulting
in pressure loss in the pipeline, the temperature of hydraulic medium and the load of the hydraulic butterfly valve. The simulation
results and analysis provide a theoretical basis for the choice of the total capacity of the accumulator and pipeline diameters
in a throttle governing system with a hydraulic butterfly valve. It also determines the type and specification of the hydraulic
butterfly valve and the design of motion parameters of the transported fluid. 相似文献
967.
Joseph Broach Jennifer Dill John Gliebe 《Transportation Research Part A: Policy and Practice》2012,46(10):1730-1740
To better understand bicyclists’ preferences for facility types, GPS units were used to observe the behavior of 164 cyclists in Portland, Oregon, USA for several days each. Trip purpose and several other trip-level variables recorded by the cyclists, and the resulting trips were coded to a highly detailed bicycle network. The authors used the 1449 non-exercise, utilitarian trips to estimate a bicycle route choice model. The model used a choice set generation algorithm based on multiple permutations of path attributes and was formulated to account for overlapping route alternatives. The findings suggest that cyclists are sensitive to the effects of distance, turn frequency, slope, intersection control (e.g. presence or absence of traffic signals), and traffic volumes. In addition, cyclists appear to place relatively high value on off-street bike paths, enhanced neighborhood bikeways with traffic calming features (aka “bicycle boulevards”), and bridge facilities. Bike lanes more or less exactly offset the negative effects of adjacent traffic, but were no more or less attractive than a basic low traffic volume street. Finally, route preferences differ between commute and other utilitarian trips; cyclists were more sensitive to distance and less sensitive to other infrastructure characteristics for commute trips. 相似文献
968.
Sloshing phenomenon in the liquid cargo carriers has caught the attention of researchers as the interaction between the sloshing
waves and structure is one of the key point and difficulty in the study of sloshing. In this paper, we captured the free surface
with a volume of fluid (VOF) method and then calculated the motions and responses of the structure by adopting the Reynolds-averaged
Navier-Stokes (RANS) equations for the whole fluid domain. With the use of user defined functions (UDF) in Fluent, the interaction
between fluid and structure was then simulated. As a reasonable simplification, the authors studied the response of a single
cantilever in a tank under sloshing loads; Further study should pay more attention to the mechanisms of interaction between
sloshing waves and elastic structures. 相似文献
969.
For the large-scale application requirements of the belt-type networks, the mathematical modeling as well as quantitative
analysis for the scalability of the network based on average path length is completed in this paper, and the theorem for the
scale scalability of the belt-type networks is derived. The theorem provides a calculation formula for the upper limit of
node scale theory of the belt-type networks and a calculation formula for the upper limit of single node load theory. 相似文献
970.
Workshop 3A focussed on matters of institutional design that seem likely to improve public transport outcomes. It started by defining high level outcome goals, as measures of ultimate public transport success, and then identified the major societal issues that public transport systems can help to resolve. These issues were separately defined for Southern African and western settings. The importance of taking an integrated approach to transport, particularly land use/transport integration, was seen as fundamental to goal achievement. Workshop papers provided many and varied examples of this importance, ranging from PPPs for major public transport projects to system design issues and contracting out of services. The Workshop included detailed discussion on paratransit development in Southern Africa, where relationship management is proving to be critical, in-line with much previous Thredbo discussion about the important role of trusting partnerships. Parallels and contrasts were drawn with paratransit in western settings. Competition in passenger rail was also a focus, with some questioning of the benefits of franchising. Discussion concluded by proposing recommendations for policy and research and suggesting agenda items for future Thredbo Conferences. 相似文献