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31.
For the development of 19-plex Y STR system and polymorphism studies in locl ethnic populations sixteen markers of non-recombining regions (NRY) of Y chromosome, which show high power of discrimination among individuals, were selected in this study. Blood samples (600) were e.ollected from the males of three most common castes of Pakistani population (Arnin, Awan and Rajput) with different parent lineages. Three markers (DYS385a/b, DYS389Ⅰ/Ⅱ and YCAⅡa/b) among 16 Y STRs are double-targeted regions of the Y chromosome and thus provide two polymorphie peaks for each respective primer set. These 16 Y-STRs were developed into Megaplex system for simultaneous amplification of all markers within the population. The overall power of discrimination observed in focused populations was 60.5%, 66.5% and 55% in Rajput, Awan and Arain casts respectively. This discrimination power will be helpful in haman identification for forensic casework studies including sexual assaults and paternity testing.  相似文献   
32.
This paper considers the determination of the maximum shipping capacity of the Suez canal. Initially, some assumptions are made in order to calculate the ‘theoretical’ maximum capacity in terms of ‘standard ships’. This last term defines ships which transit the Canal at a given speed and at a given time interval from the vessel ahead and astern.

Data has been collected from the Canal Zone, the analysis of which provides the necessary information regarding speeds of vessels at different sections of the Canal, time gaps between different classes of ship at different nodes of the Canal, and relationships between time widths of convoys and numbers of ships in those convoys at different points of the Canal.

This data has then been used to calculate the maximum capacity of the Canal in terms of ‘real ships’. For that purpose four schemes have been devised, each taking a different mix of categories of ships. A sensitivity analysis has been undertaken in order to investigate the effect of each class of ship on the real maximum shipping capacity of the Canal. The last two schemes take into consideration the effect of the future introduction of supertankers.  相似文献   
33.
IntroductionThemainfeatureoftheC-DTListhatithasaphaseerrordetectorwithlinearcharacteristics,whichmeansthatithasawiderlock-inr...  相似文献   
34.
The positioning quality of global navigation satellite system (GNSS), or GNSS quality of service (QoS), is a major factor impacting real-time navigation performance. Commonly requested routes (i.e., shortest or fastest) may include areas with poor GNSS QoS, which can subsequently degrade navigation performance. To provide alternative routes with high or acceptable GNSS QoS along a route, a novel optimal routing for navigation systems/services based on GNSS QoS by utilizing integrated GNSS (iGNSS) QoS prediction is presented in this article. New routing criteria based on GNSS QoS are maximum availability, maximum accuracy, maximum continuity, and maximum reliability. Two experiments were conducted to compare GNSS QoS-based routes against shortest routes. In one experiment, routes were simulated, and in another, generated routes based on GNSS QoS were evaluated against GPS-based trajectories as ground truths. The results show that GNSS QoS-based routes provide routes with higher QoS, more than 50%, and longer, about 50%, than shortest routes.  相似文献   
35.
In this paper, a method for designing a statistically valid sample of bridges is proposed. The need for such a sampling procedure arises from the impracticality of a detailed analysis of the structural effects of new candidate truck configurations on the whole bridge inventory. In this study, a set of bridges from the national inventory was determined for the purpose of selecting a bridge sample. This set of bridges is referred to as the population. The selection of bridges for inclusion in the population was based on the status of the bridge, type of service, structural material, structural system type and functional class. The stratified sampling method was used in the determination of the required sample sizes. According to this method, the population was first divided into sub-populations, or strata. These sub-populations were non-overlapping. In turn, each strata was divided into sub-strata. The characteristics of each sub-stratum were estimated and combined to determine the characterics of the strata. Then the characteristics of the strata were combined to determine the characteristics of the bridge population. A comparison of the results based on the sample and bridge population was conducted in order to verify the validity of the proposed sampling procedure.  相似文献   
36.
The benefit, in terms of social surplus, from introducing congestion charging schemes in urban networks is depending on the design of the charging scheme. The literature on optimal design of congestion pricing schemes is to a large extent based on static traffic assignment, which is known for its deficiency in correctly predict travel times in networks with severe congestion. Dynamic traffic assignment can better predict travel times in a road network, but are more computational expensive. Thus, previously developed methods for the static case cannot be applied straightforward. Surrogate‐based optimization is commonly used for optimization problems with expensive‐to‐evaluate objective functions. In this paper, we evaluate the performance of a surrogate‐based optimization method, when the number of pricing schemes, which we can afford to evaluate (because of the computational time), are limited to between 20 and 40. A static traffic assignment model of Stockholm is used for evaluating a large number of different configurations of the surrogate‐based optimization method. Final evaluation is performed with the dynamic traffic assignment tool VisumDUE, coupled with the demand model Regent, for a Stockholm network including 1240 demand zones and 17 000 links. Our results show that the surrogate‐based optimization method can indeed be used for designing a congestion charging scheme, which return a high social surplus. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
37.
A map-matching algorithm is an integral part of every navigation system and reconciles raw and inaccurate positional data (usually from a global positioning system [GPS]) with digital road network data. Since both performance (speed) and accuracy are equally important in real-time map-matching, an accurate and efficient map-matching algorithm is presented in this article. The proposed algorithm has three steps: initialization, same-segment, and next-segment. Distance between the GPS point and road segments, difference between the heading of the GPS point and direction of road segments, and difference between the direction of consecutive GPS points and direction of road segments are used to identify the best segment among candidates near intersections. In contrast to constant weights applied in existing algorithms, the weight of each criterion in this algorithm is dynamic. The weights of criteria are calculated for each GPS point based on its: (a) positional accuracy, (b) speed, and (c) traveled distance from previous GPS point. The algorithm considers a confidence level on the assigned segment to each GPS point, which is calculated based on the density and complexity of roads around the GPS point. The evaluation results indicate 95.34% correct segment identification and 92.19% correct segment assignment. The most important feature of our algorithm is that the high correct segment identification percentage achieved in urban areas is through a simple and efficient weight-based method that does not depend on any additional data or positioning sensors other than digital road network and GPS.  相似文献   
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