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101.
We have developed an advanced inversion charge model for both n-type and p-type symmetrical Double-Gate MOSFETs where quantum mechanical effects (QMEs) have been included. By doing so, the role of different crystallographic orientations was successfully taken into account. Self-consistent Poisson and Schrödinger simulators were used to check the accuracy of the model presented. As a starting point, a classical inversion charge centroid model was considered. Afterwards, an inversion charge model was developed including QMEs by means of a corrected oxide capacitance. The validity of the model was checked for the three common wafer orientations (1 0 0), (1 1 0) and (1 1 1) and for devices with different silicon layer (tSi) and oxide (tox) thicknesses. As it will be shown, the model reproduces correctly the simulation data both in the subthreshold and in the strong inversion operation regime.  相似文献   
102.
Reference has been made in the literature of the variability in the clinical presentation of deficiency of complex III of the respiratory chain, identifying up to the moment, four groups, the first of which is characterized by hipotonia and wearness starting at variable ages. We report a new case of mitochondrial myopathy due to deficiency of this complex and included within this first group, and consider the importance of defining the clinical and histochemical characteristics of this polymorphous entity.  相似文献   
103.
Electron transport properties in SiC quantized inversion layers have been studied by means of a Monte Carlo procedure. It has been observed that the contribution of polar-optical phonon scattering produces a significant influence of the effective-electric field on the high longitudinal field transport regime, this being the main difference of SiC with respect to standard Si inversion layers. The energy- and momentum-relaxation times have been calculated and the results suggest that electron velocity overshoot effects are less important than in Si metal-oxide semiconductor field effect transistors. The electron mobility is not very different from their silicon counterparts, but the saturation velocity is higher.  相似文献   
104.
The hepatitis C virus (HCV) subtype distribution among intravenous drug users (IVDU), and patients without this risk of acquiring HCV infection, was evaluated. The patients included in the study were 51 with chronic type C hepatitis (36 IVDU and 25 coinfected by HIV-1), and 31 on haemodialysis. Genotyping was performed on 71 viraemic patients, with the following distribution: 25.4%, 1a; 54.9%, 1b; 8.5%, 3a; 7%, mixed (1a, 1b; 3a, 1a; 3a, 1b; 2 x 3a, 2a); 1.4%, 4; and 2.8%, non-typeable. When subtypes were related to IVDU practice, the statistical significance was p < 0.01 for subtypes 1a (48.5% vs 7.5%, for IVDU and non-IVDU, respectively) and 1b (16.1% vs 85.1%). No relation between HIV-1 coinfection and subtype distribution was observed among IVDU patients. The results suggest that among young IVDU of Southern Spain the emerging HCV subtype is 1a.  相似文献   
105.
Metal‐halide perovskites have emerged as promising materials for optoelectronics applications, such as photovoltaics, light‐emitting diodes, and photodetectors due to their excellent photoconversion efficiencies. However, their instability in aqueous solutions and most organic solvents has complicated their micropatterning procedures, which are needed for dense device integration, for example, in displays or cameras. In this work, a lift‐off process based on poly(methyl methacrylate) and deep ultraviolet lithography on flexible plastic foils is presented. This technique comprises simultaneous patterning of the metal‐halide perovskite with a top electrode, which results in microscale vertical device architectures with high spatial resolution and alignment properties. Hence, thin‐film transistors (TFTs) with methyl‐ammonium lead iodide (MAPbI3) gate dielectrics are demonstrated for the first time. The giant dielectric constant of MAPbI3 (>1000) leads to excellent low‐voltage TFT switching capabilities with subthreshold swings ≈80 mV decade?1 over ≈5 orders of drain current magnitude. Furthermore, vertically stacked low‐power Au‐MAPbI3‐Au photodetectors with close‐to‐ideal linear response (R2 = 0.9997) are created. The mechanical stability down to a tensile radius of 6 mm is demonstrated for the TFTs and photodetectors, simultaneously realized on the same flexible plastic substrate. These results open the way for flexible low‐power integrated (opto‐)electronic systems based on metal‐halide perovskites.  相似文献   
106.
The extant literature has highlighted the importance of knowledge transfer between a buyer and its supply network for strengthening supply chain competence. This is a bi-directional exchange where the buyer and supply network each act as the sender and receiver of knowledge. Prior research has however largely focused on the knowledge recipient only. We consider both sender and recipient using two key dynamic capabilities related to knowledge transfer: (i) desorptive capacity, which enables the safe transfer of knowledge from the sender; and, (ii) absorptive capacity, which enables the acquisition and assimilation of external knowledge by the recipient. Using the concept of ‘fit’, we investigate whether organisations strengthen supply chain competence when their desorptive capacity exceeds that of their supply network's (positive misfit) and consider the moderating role of the organisation’s and supply network’s absorptive capacity. Multiple regression analysis of survey data from 250 firms identifies an inverted U-shaped relationship between positive desorptive capacity misfit and supply chain competence. Further, this relationship is shown to be moderated by the supply network’s absorptive capacity level. The paper furthers our understanding of supply chain knowledge management enabling buyers and their supply networks to achieve more successful knowledge transfer outcomes.  相似文献   
107.
Intervention teams act in hostile scenarios where reducing mission times and accident risks is critical. In these situations, the availability of accurate information about the environment plays a key role in ensuring the well-being of rescuers and victims. This information required to plan the interventions in indoor emergencies encompasses the location of fires and the presence of dangerous gases. Robotics and remote sensing technologies can help emergency teams to obtain this information in real-time without exposing themselves. Additionally, the accurate simulation of the environments allows the teams to plan their interventions, creating routes to safely access the affected areas and evacuate the victims. This article presents a robotic solution developed to satisfy the demands of intervention teams. More specifically, it describes an autonomous ground robot that can obtain real-time location and environmental data from indoor fires, as well as a simulator that reproduces these emergency scenarios and facilitates mission planning. In this way, emergency teams can know the conditions in the scenario before, during, and after the intervention. Thus, risks are minimized by improving their situational awareness and reducing their exposure times during the mission. The system has been developed and validated in collaboration with the end-users and under realistic harsh environments. During these experiments, the robot was used to detect fire sources and cold smoke and provide environmental information to firefighters. Additionally, the simulator provided alternative routes for accessing and exiting the scene faster and safer by dodging potentially dangerous areas.  相似文献   
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