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81.

Smart vehicles form pervasive environment to enhance user experience through multimedia enabled infotainment systems. In order to realize effective infotainment system for vehicles, we need to have context-aware applications that use latest (live) information for enhanced user experience. Such latest information is abundantly available on the Internet due to explosive growth of Web 3.0, which can be accessed through wireless communication infrastructures such as VANETs and LTE. In this paper we propose a cloud-based middleware framework, InCloud, for vehicular infotainment application development. The proposed framework follows service oriented architecture in which data filtering and fusion functionalities are delegated to the cloud. Data filtering and fusion reduce the data flow over wireless link. Furthermore, because most of the processing is done on the cloud, the client becomes lightweight and loosely coupled with Internet resources and underlying platforms in vehicles. We also propose a class-based fusion method for combining information from multiple resources on the Internet. The efficacy of the proposed framework is validated by developing three infotainment applications for vehicles: context-aware music, news, and an enhanced Direction (eDirection) application.

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82.
83.
Stanton NA  Walker GH  Young MS  Kazi T  Salmon PM 《Ergonomics》2007,50(8):1209-1234
This paper reports on the study of an advanced driver coaching system. The study distinguishes between different types of post-licensure programmes in order to explore a system based on a model of identifying and responding to hazards, called 'information, position, speed, gear and acceleration' (IPSGA). Previous literature has been sceptical about the benefits of advanced driver education; thus, the current study was designed to control for the effects of coaching drivers in the 'IPSGA' system (the treatment group) against the effects of being accompanied (control group 1), as well as the mere effects of time (control group 2). Measures were taken before the driver coaching began (as a baseline measure) and again after 8 weeks (to see if any changes had occurred). These measures included driver knowledge via a post-drive interview, observations of driving skill and driver attitude using a locus of control scale. The results suggest that advanced driver coaching using the IPSGA system had a beneficial effect on all of these measures. Drivers in the coaching condition improved their situation awareness, driving skills and reduced attributions of external locus of control. The study lends support to the case for one-to-one individualized driver coaching using a systematic model of driving.  相似文献   
84.
We propose a new strategy to synthesize heat exchanger networks with detailed designs of individual heat exchangers. The proposed strategy uses a multistep approach by first obtaining a heat exchanger network topology through solving a modified version of the mixed integer nonlinear programming (MINLP) stage-wise superstructure of Yee and Grossmann, which includes a smoothed LMTD approximation and pressure drops. In a second nonlinear programming (NLP) suboptimization step, we allow for nonisothermal mixing to solve problems with or without exchanger bypasses. The selected heat exchangers along with the mass and energy balances obtained are then used to design the network with detailed exchanger designs through solving a sequence of NLPs for individual heat exchanger designs. The NLPs are based on the detailed discretized optimization models of Kazi et al., which solve quickly and reliably to obtain heat exchangers based on rigorous, first-principles derived coupled differential equations. These models solve a differential algebraic equation system and do not rely on usual assumptions associated with other heuristic-based exchanger design methods, such as log mean temperature difference and FT correction factors. These detailed exchanger designs are then used to update the network optimization model through sets of correction factors on heat exchanger area, number of shells, heat transfer coefficients, and pressure drops of each exchanger design, in a method based on that of Short et al. The method solves reliably, guaranteeing feasible exchangers for every potential network generated by the shortcut models, through validation with rigorous heat exchanger models at every iteration. In addition, the method does not increase the nonlinearity of the MINLP model, nor does it require any manual intervention or initialization from the user. Three examples are solved and the results are compared to those obtained in the literature.  相似文献   
85.
The stress-strain relation of aluminum (Al) alloy foam cell wall was evaluated by the instrumented sharp indentation method. The indentation in a few micron ranges was performed on the cell wall of Al-alloy foam having a composition of Al-3wt.%Si-2wt.%Cu-2wt.%Mg as well as its precursor (material prior to foaming). To extract the stress-strain relation in terms of yield stressσ y, strain hardening exponentn and elastic modulusE, the closed-form dimensionless relationships between load-indentation depth curve and elasto-plastic property were used. The tensile properties of precursor material of Al-alloy foam were also measured independently by uni-axial tensile test. In order to verify the validity of the extracted stress-strain relation, it was compared with the results of tensile test and finite element (FE) analysis. A modified cubicspherical lattice model was proposed to analyze the compressive behavior of the Al-alloy foam. The material parameters extracted by the instrumented nanoindentation method allowed the model to predict the compressive behavior of the Al-alloy foam accurately.  相似文献   
86.
In this paper, building to grid (B2G) and vehicle to grid (V2G) have been defined with clear and practical understanding. Both of them are new generation technologies which are the essential part of smart city living and crowd energy clustering. Firstly, an in-detailed overview has been provided with an introduction to B2G and V2G followed by a historical overview and theoretical analysis in respect to smart city planning. Next, a review is conducted on current and previous smart living research, which deals with B2G and V2G. Efficient B2G and V2G implementations in practical cases then have been discussed. Lastly, both of these technical prospects have been analyzed in crowd energy diagram.  相似文献   
87.
Streamflow simulation is often challenging in mountainous watersheds because of irregular topography and complex hydrological processes. Rates of change in precipitation and temperature with respect to elevation often limit the ability to reproduce stream runoff by hydrological models. Anthropogenic influence, such as water transfers in high altitude hydropower reservoirs increases the difficulty in modeling since the natural flow regime is altered by long term storage of water in the reservoirs. The Soil and Water Assessment Tool (SWAT) was used for simulating streamflow in the upper Rhone watershed located in the south western part of Switzerland. The catchment area covers 5220 km2, where most of the land cover is dominated by forest and 14 % is glacier. Streamflow calibration was done at daily time steps for the period of 2001–2005, and validated for 2006–2010. Two different approaches were used for simulating snow and glacier melt process, namely the temperature index approach with and without elevation bands. The hydropower network was implemented based on the intake points that form part of the inter-reservoir network. Subbasins were grouped into two major categories with glaciers and without glaciers for simulating snow and glacier melt processes. Model performance was evaluated both visually and statistically where a good relation between observed and simulated discharge was found. Our study suggests that a proper configuration of the network leads to better model performance despite the complexity that arises for water transaction. Implementing elevation bands generates better results than without elevation bands. Results show that considering all the complexity arising from natural variability and anthropogenic influences, SWAT performs well in simulating runoff in the upper Rhone watershed. Findings from this study can be applicable for high elevation snow and glacier dominated catchments with similar hydro-physiographic constraints.  相似文献   
88.
The transverse modal behavior of Metal-Insulator (Oxide)-Semiconductor (MIS) heterostructure injection lasers is analyzed. MIS structures have been proposed by Jain and Marciniec as an alternate approach to p-n heterojunctions to obtain minority carrier injection and subsequent lasing action. In the modal analysis the MIS structure is treated as an asymmetrical three-layer slab waveguide with appropriate boundary conditions. Numerical computations of electric field strength, intensity and confinement factor P are presented for various GaAs and InP based MIS structures. A comparison of the output characteristics of a GaAs MIS laser with a conventional GaAs p-n double heterostructure laser is also reported.  相似文献   
89.
An extremely sensitive and selective voltammetric method was developed for the determination of roxarsone (ROX) at a newly modified carbon paste microelectrode in Britton–Robinson buffer (BRB) at pH 2.0. The electrode is based on a disposable plastic pipette tip filled with carbon paste based on a mixture of graphite powder and Amberlite XAD-4 (5:1, w/w). The experimental parameters, such as pH, type of the buffer, mode of voltammetry, accumulation potential, accumulation time, and stirring rate were optimized. The reduction peak current dependences were linear for the concentration of ROX from 2.0 to 100 μM. The method showed reproducible results with RSD (n?=?11) of <2.0 %. The limit of detection (LOD) and limit of quantification (LOQ) were 0.53 and 1.76 μM, respectively. ROX showed that there was no apparent surface passivation indicating the suitability of the modified electrode for ROX detection. The developed method was successfully applied for the determination of ROX in poultry feed and poultry litter collected from various localities of Hyderabad.  相似文献   
90.
Cognitive radio sensor network (CRSN) is an intelligent and reasonable combination of cognitive radio technology and wireless sensor networks. It poses significant challenges to the design of topology maintenance techniques due to dynamic primary-user activities, which in turn decreases the data delivery performance of the network as well as it’s lifetime. This paper aims to provide a solution to the CRSN clustering and routing problem using an energy aware event-driven routing protocol (ERP) for CRSN. Upon detection of an event, the ERP determines eligible nodes for clustering according to local positions of CRSN nodes between the event and the sink and their residual energy levels. Cluster-heads are selected from the eligible nodes according to their residual energy values, available channels, neighbors and distance to the sink. In ERP, cluster formation is based on relative spectrum awareness such that channels with lower primary user appearance probability are selected as common data channels for clusters. For data routing, ERP employs hop-by-hop data forwarding approach through the CHs and primary/secondary gateways towards the sink. Through extensive simulations, we demonstrate that the proposed ERP provides with better network performances compared to those of the state-of-the-art protocols under a dynamic spectrum-aware data transmission environment.  相似文献   
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