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951.
952.
The aim of this paper is to study traffic properties in an on/off-ramp system with a bus stop close to the on/off ramp. The location of the bus stop in the on/off-ramp (thereafter downstream or upstream case) is discussed. The simulation results show that in the two ramp systems, the reasons for traffic congestions are different. In the on-ramp system, buses and cars coming from on-ramp interweave each other, while in the off-ramp system, busesinterweave with cars exiting to off-ramp. Thus, in the on-ramp (off-ramp) system, the upstream (downstream) bus stop is helpful to reduce the interweaving situation. Moreover, the negative effect will disappear when the distance between the bus stop and the on/off-ramp is more than 20 cells (i.e. 150 m). These qualitative findings may provide some suggestions on traffic management and optimization. 相似文献
953.
A continuum traffic flow model with the consideration of coupling effect for two-lane freeways 总被引:2,自引:0,他引:2
A new higher-order continuum model is proposed by considering the coupling and lane changing effects of the vehicles on two adjacent lanes. A stability analysis of the proposed model provides the conditions that ensure its linear stability. Issues related to lane changing, shock waves and rarefaction waves, local clustering and phase transition are also investigated with numerical experiments. The simulation results show that the proposed model is capable of providing explanations to some particular traffic phenomena commonly observable in real traffic flows. 相似文献
954.
955.
A new method to determine the minimum measurement time interval needed to obtain the equivalent continuous A-weighted sound pressure level with a designated reliability is presented. This method considers variations in the noise emission from passing vehicles. To verify the validity and availability, simulation experiments based on our dynamic model are examined under various traffic conditions. A statistic quantity, the mean time interval between two maximum sound pressure levels consecutively observed during the reference measurement time interval, is introduced in the experimental analysis. Additionally, the theoretical analysis includes another statistic quantity corresponding to the mean time interval, the mean recurrence time of the maximum sound pressure level, when the transition probability, rate of heavy vehicles, and probability distribution of vehicles passing the observation point during the reference measurement time interval are known. 相似文献
956.
In this paper, an extended Biham–Middleton–Levine (BML) model is proposed to simulate complex characteristics of four-directional traffic flow by considering the effect of slow-to-start. The simulation results show that the system does not exhibit a sharp transition from moving phase to jamming phase, which is consistent with the results of the latest studies about the original BML model. Differently from the structure geometric patterns in previous studies, a new phase separation phenomenon, i.e., the coexistence of multiple free flow stripes and multi-local jams, can be observed. The formation mechanisms of typical dynamic patterns are also explored. Furthermore, a mean field analysis for the maximum velocity in the moving phase is obtained, which is in good accordance with simulation results. In addition, an interesting feature is found that this new coexistence phenomenon of two phases is determined only by the effect of slow-to-start and is completely independent of traffic light (only considering red light and green light) period. 相似文献
957.
We are developing an optical layer-2s witch network that uses both wavelength-division multiplexing and time-division multiplexing technologies for efficient traffic aggregation in metro networks.For efficient traffic aggregation,path bandwidth control is key because it strongly affects bandwidth efficiency.For this paper,we propose a dynamic time-slot allocation method that uses periodic information of difference values of traffic variation.This method can derive near-optimal allocation with lower computational cost,which enlarges the maximum available network size compared with conventional time-slot allocation methods.Numerical results show that the proposed method enables dynamic path control in 1K-node-scale optical layer-2s witch network,which leads to cost-effective metro networks. 相似文献
958.
Andrei Reztsov 《Complexity》2016,21(5):328-330
Self‐organising traffic lights (SOTL) are considered a promising instrument for the development of more efficient adaptive traffic control systems. In this paper, we explain why this technology should be scrutinised and carefully reviewed. Research projects based on SOTL currently under way should be reviewed too. © 2015 Wiley Periodicals, Inc. Complexity 21: 328–330, 2016 相似文献
959.
Takashi Nagatani 《Applied Mathematical Modelling》2012,36(2):702-711
A model for the facing pedestrian traffic on a passage with a partition line at rush hour is developed. The model is described by a bi-directional cellular automaton (CA) model with four species. The CA model is not stochastic but deterministic. If the passage is congested and the local density is superior to the threshold, walkers to the east and to the west try to move separately changing their lane as the traffic rule is imposed on pedestrians at a high density. Walkers move freely ignoring the partition line at a low density. The traffic-rule effect at rush hour is taken into account in addition to the excluded-volume effect and bi-directionality. The pedestrian behavior under the traffic rule is clarified. 相似文献
960.
We propose a simple cellular automaton for traffic flow within the fundamental diagram, which could reproduce aspects of the three-phase theory. This so-called average space gap model (ASGM) is based on the Nagel–Schreckenberg model with additional slow-to-start and anticipation rules. The anticipation rule takes into account the average space gap of multiple leading vehicles and conveys to the model its three-phase property. Due to the anticipation rule, ASGM can show the transition from free flow to synchronized flow. Due to the slow-to-start rule, ASGM can show the spontaneous wide moving jam emerges in the synchronized flow. Simulations are carried out for periodic and open boundary conditions. Under periodic boundary condition, the fundamental diagram, and the properties of synchronized flow are studied. Under open boundary condition, different congested patterns induced by an on-ramp are analyzed. We found that the ASGM produces the same spatiotemporal dynamics as many of the more complex three-phase models. Due to its simplicity and its close relation to conventional slow-to-start models, this model can shed light on the relation between ‘two-phase’ and three-phase models. 相似文献