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1.
Non-ischemic dilated cardiomyopathy encompasses a wide spectrum of myocardial disorders, characterized by left ventricular dilatation with systolic impairment and increased risk of sudden cardiac death. In spite of all the therapeutic progress that has been made in recent years, dilated cardiomyopathy continues to be an important cause of cardiac transplant, being associated with an enormous cost burden for health care systems worldwide. Predicting the prognosis of patients with dilated cardiomyopathy is essential to individualize treatment. Late gadolinium enhancement-cardiac magnetic resonance imaging, microvolt T-wave alternans, and genetic testing have emerged as powerful tools in predicting sudden cardiac death occurrence and maximizing patient’s selection. Despite all these new diagnostic modalities, additional tests to complement or replace current tools are required for better risk stratification. Therefore, biomarkers are an easy and important tool that can help to detect patients at risk of adverse cardiovascular events. Additionally, identifying potential biomarkers involved in dilated cardiomyopathy can provide us important information regarding the diagnostic, prognostic, risk stratification, and response to treatment for these patients. Many potential biomarkers have been studied in patients with dilated cardiomyopathy, but only a few have been adopted in current practice. Therefore, the aim of our review is to provide the clinicians with an update on the well-known and novel biomarkers that can be useful for risk stratification of patients with non-ischemic dilated cardiomyopathy.  相似文献   
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Spatial diversity can be induced by using wireless relay stations, which cooperate by amplifying and retransmitting the information received from a source to a destination station. In this context we propose a distributed space-time coding (DSTC) system based on the Alamouti codes. We characterize the symbol error rate of systems with one and two non-regenerative relays using bounds and high signal-to-noise ratio (SNR) approximations. The asymptotic (high SNR) symbol error probability formulas are used to optimize the power allocation in the DSTC system. Furthermore, using the asymptotic symbol error probability formulas we argue that the DSTC system has at least 1.5 times the diversity achieved by point-to-point transmissions with the same bandwidth. Simulations show not only that the DSTC outperforms the amplify-and-forward cooperative system with orthogonal transmissions, but also convolutional encoded one-hop transmissions with the same information rate as the DSTC system. Assuming full channel knowledge at the source and the relays, we find an optimum cooperative system by minimizing the bit error rate of the DSTC system with one and two non-regenerative relays subject to fixed transmit energy constraints at each radio. Numerical results show that the DSTC system with two relays performs very close to the optimum cooperative system.  相似文献   
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This letter reports on the extraction of the threshold voltage of laterally diffused MOS transistors. A clear analysis of the device physics is performed, highlighting the correlation between the change of the electron charge distribution along the channel and the device capacitance variations when the gate voltage is swept. Using numerical simulations, it is shown that the peak of the gate-to-drain capacitance is related to the transition of the surface from weak to moderate inversion in the intrinsic MOS transistor at the location of the maximum doping concentration, which corresponds to the threshold voltage of the device according to the MOS theory. Comparison between conventional I/sub D///spl radic/g/sub m/ extraction and the new proposed capacitance peak method is performed on both technology computer-aided design simulations and measurements in order to confirm the new experimental technique and related theory.  相似文献   
4.
The esterification of cellulose hydroxyl groups with natural carboxylic acids in mild conditions represents an adequate pathway in obtaining cellulose derivatives with different useful properties. In this article, authors report the synthesis of new mixed ester of cellulose and cellulose acetate nicotinate (CAN) , in a homogenous medium using DMF as solvent, cellulose acetate (CA) as starting cellulosic material, and nicotinic acid as an esterification agent in the presence of p-toluenesulfonyl chloride and pyridine. FTIR and NMR techniques were used to prove the binding of nicotinoyl group at free hydroxyl groups of CA. The obtained CAN was electrospun by electrospinning technique to obtain adsorbent ultrafine fibers, evidenced by SEM images, with high specific surface area. Monolayer Langmuir and empirical Leundrich isotherms were used to assess the adsorption capacity for rhodamine B dye of electrospun CAN in comparison with that of electrospun CA used as starting material. Langmuir isotherm led to a better assessment of experimental data suggesting that the adsorption is mainly determined by hydrogen bonds formed between carboxylic OH hydrogen bonding donor and pyridine N hydrogen bonding acceptor. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47772.  相似文献   
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Post-dryout heat transfer to high pressure water was investigated experimentally in vertical tubes and annuli containing various flow obstacles. The operational conditions during the experiments were as follows: mass flux from 500 to 1750 kg/m2 s, pressure from 5 to 9 MPa, inlet subcooling from 10 to 40 K and heat flux up to 1.5 MW/m2. Five different test sections were used in experiments: three annular test sections with inner diameter 12.7 mm and outer diameter 24.3 mm, containing cylindrical and grid flow obstacles in the upper part, and two tubular test sections with inner diameter 24.3 mm with and without pin flow obstacles. The heated length in all test sections was 3650 mm. The wall temperature was measured with 88 thermocouples located along the inner rod and the outer tube surfaces. Due to the presence of flow obstacles, only developing post-dryout heat transfer was observed. Selected post-dryout heat transfer correlations were compared to the experimental data. It has been concluded that all tested correlations predict significantly higher wall temperatures than those obtained in the present experiment. A simple correction function to the Saha model has been suggested which significantly improves the agreement between the correlation and the present data.  相似文献   
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This work considers a SET (single event transient) fault simulation technique to evaluate the probability that a transient pulse, born in the combinational logic, may be latched in a storage cell. Fault injection procedures and a fast fault simulation algorithm for transient faults were implemented around an event driven simulator. A statistical analysis was implemented to organize data sampled from simulations. The benchmarks show that the proposed algorithm is capable of injecting and simulating a large number of transient faults in complex designs. Also specific optimizations have been carried out, thus greatly reducing the simulation time compared to a sequential fault simulation approach.  相似文献   
9.
This paper presents an overview of test and reliability approaches for approximate computing architectures. We focus on how specific methods for test and reliability can be used to improve the characteristics of approximate computing in terms of power consumption, area, life expectancy and precision. This paper does not address specification and design of approximate hardware/software/algorithms, but provides an in-depth knowledge on how the reliability and test related techniques can be efficiently used to maximize the benefits of approximate computing.  相似文献   
10.
The high sensitivity of nanotube transistors is used for the first time as a probe to study charge dynamics at a dielectric/polymer (polythiophene) interface, an inorganic/organic junction of particular importance for organic solar cells, and organic field effect transistors (OFETs). A carbon nanotube field effect transistor is coated with a thin film of a photoconductive polymer and photoexcited so as to generate carriers in the structure. Comparison between devices using SiO2 and TiO2 as gate dielectric reveals the critical role of the dielectric and clearly elucidates the relative contributions of the polymer and the dielectric layers on the separation, trapping, and relaxation of photogenerated charges.  相似文献   
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