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41.
Electrochemical techniques were used to investigate the effect of cysteine (cys) on the dissolution behavior of Cu10Ni alloy in sulfide-polluted salt water through the analysis of the alloy electrochemical behavior including Tafel polarization and electrochemical frequency modulation (EFM) along with scanning electron microscopy (SEM) and energy dispersive X-ray diffraction (EDX). The results showed that cys acts as a mixed type inhibitor. The dissolution rate decreases with increasing cys concentration and increases with increasing the temperature. An adherent layer of inhibitor molecules on the alloy surface is proposed to account for their inhibitive action. The adsorption of cys on the active cathodic sites was found to follow the Langmuir adsorption isotherm from which the thermodynamic parameters of adsorption and corrosion processes were determined and discussed. A synergistic effect was observed between cys and potassium iodide (KI). EFM data are in good agreement with SEM and EDX results.  相似文献   
42.
Clean Technologies and Environmental Policy - The refining industry is an energy-intensive industry; most of the energy is consumed in heating and cooling requirements. Revamping or retrofitting of...  相似文献   
43.
The considerable development in Saudi Arabia has obliged testing stations to make great strides in a short time. Here, scientists at the Materials Testing Laboratory in Riyadh explain how they used an accelerated procedure to predict the compressive strength of different Portland cements within 30 hours. The results were on average within ± 5 per cent of the strengths revealed by the conventional watercuring methods.  相似文献   
44.
Emergency Department (ED) triage is a process of determining illness severity and accordingly assigning patient priority. The Emergency Severity Index (ESI) is a 5-level acuity categorization system that aides in triage. This paper compared the capabilities of predicting ESI level using ordinal logistic regression (OLR), artificial neural networks (NNs), and naïve Bayesian networks (NBNs). Data were obtained from Susquehanna Williamsport Hospital for 947 patients over a one month period in 2008. It contained the assigned ESI level, chief complaint, systolic blood pressure, pulse, respiration rate, temperature, oxygen saturation level (SaO2), age, gender, and pain level. An OLR model was fit using a subset of these covariates. NBNs and NNs were modeled to relax the inherent assumptions of linearity and covariate independence in logistic regression. These three techniques were compared using incremental training dataset sizes between 50% and 100% of given data. All models were >60% accurate using the entire dataset for training. It was found that NBNs and NNs were robust to data size changes and all models had evaluation speeds of less than 0.5 s. At this time the use of NBNs is recommended considering speed, accuracy, data utilization, model flexibility, and interpretability of the model.  相似文献   
45.
Multimedia Tools and Applications - The imbalance and multi-dimension are two common problems in the medical image datasets, which affect the performances of the image processing procedures. The...  相似文献   
46.
Although most designers prefer the p-y curve method as compared to elastic continuum or finite-element analysis of laterally loaded pile behavior, the profession has reached a state where it is time that closer scrutiny be given to the traditional “Matlock-Reese” p-y curves used in the analysis. The traditional p-y curves were derived from a number of well-instrumented field tests that reflect a limited set of conditions. To consider these p-y curves as unique is questionable. As important as such curves have been to advancing the practice from elastic to nonlinear beam on elastic foundation analysis, such calibrated∕verified p-y curves reflect the specific field test conditions (particularly the pile properties) encountered. As presented in this paper, there are additional influences such as pile bending stiffness, pile cross-sectional shape, pile-head fixity, and pile-head embedment that have an effect on the resulting p-y curves. It is argued that strain wedge (SW) model formulation can be used to characterize such effects. SW model analysis predicts the response of laterally loaded piles and has shown very good agreement with actual field tests in sand, clay, and layered soils. The advantage of the SW model is that it is capable of taking into account the effect of changes in soil and pile properties on the resulting p-y curves.  相似文献   
47.
Emergency Department (ED) crowding is a major problem in the U.S. like in many other countries world-wide. This problem is adversely affecting the safety of the patients who rely on receiving a timely treatment in EDs. As a part of solving this problem, a triage process is utilized. Triage is a pre-hospital process by which patients are sorted according to the severity of their illnesses or injuries. Improvements to this process would affect the patient flow positively, and in turn would enhance patient satisfaction and quality of care. In a previous study, we developed a triage algorithm that uses Fuzzy Analytic Hierarchy Process (FAHP) and Multi-Attribute Utility Theory (MAUT) to rank the patients according to their characteristics: chief complaint, age, gender, pain level, and vital signs. The main purpose of this study is to compare two triage systems using Discrete Event Simulation (DES); one system uses the typical Emergency Severity Index (ESI), and the other uses the FAHP and MAUT algorithm. Overall, there was no strong statistical evidence that either system would do better than the other for all the performance measures when the average is taken across all ESI levels. On the other hand, the collected simulated data by each ESI level showed that the FAHP–MAUT algorithm tends to balance the time-to-bed (TTB) and length of stay (LOS) for ESI levels 2–5. In terms of the percentage of tardy patients, FAHP–MAUT system significantly outperforms the ESI system for ESI levels 4 and 5; 34% vs. 61% and 25% vs. 70%, respectively. Both systems were performing about equally for ESI level 1 and level 3 patients; 25% vs. 26% and 64% vs. 67%, respectively. While ESI system slightly outperforms FAHP–MAUT system for ESI level 2 patients, 56% vs. 66%. Based on these results, we recommend using FAHP–MAUT not only because it performs better in terms of minimizing the number of patients with longer than the allotted upper limits of wait times, but also it reduces potential bias and errors in decision making in clinical settings; and thus, it can be used as the basis of an expert system to advise triage nurses.  相似文献   
48.
Zaky  Zaky A.  Ahmed  Ashour M.  Aly  Arafa H. 《SILICON》2022,14(6):2765-2777
Silicon - A highly-sensitive remote temperature sensor based on Tamm resonance is proposed using a one-dimensional photonic crystal. The proposed structure is prism/Ag/Toluene/SiO2...  相似文献   
49.
工程结构服役期间经常由于使用功能改变或使用荷载增加而需要对结构进行加固改造。为研究经碳纤维布粘贴加固后的玄武岩纤维增强塑料(BFRP)筋-工程用水泥基复合材料(ECC)-混凝土组合梁的受弯性能,对3组共12根不同ECC高度替换率(0、0.29和0.58)的BFRP筋-ECC-混凝土组合梁底分别粘贴1、2和3层碳纤维布的加固构件及未加固构件进行静力受弯性能试验。研究碳纤维布粘贴层数和ECC高度替换率对组合梁受弯承载力和破坏形态的影响。试验结果表明:采用受拉性能优异的ECC替代受拉区部分混凝土形成的ECC-混凝土组合梁不仅可提高构件承载力,还可有效改善构件抵抗开裂和变形的能力;组合梁底粘贴3层碳纤维布,裂缝宽度可降至未加固试件的10%,受弯承载力提高20%,挠度降低50%。借鉴钢筋混凝土理论,基于合理的基本假定和简化的材料本构模型,提出粘贴碳纤维布加固的组合梁受弯承载力计算式,并给出碳纤维布强度折减系数,理论预测值与试验实测值吻合良好。  相似文献   
50.
Bagasse is a solid waste that remains after crushing sugarcane. Since bagasse is used as a fuel in sugar mills, characterization of its thermal degradation is rather important in order to use it efficiently. Thermal analysis of bagasse was carried out using differential thermal analysis (DTA) and thermogravimetry (TG) under oxidizing and inert atmospheres. Kinetic studies were based on weight loss obtained from TG analysis. Thermal degradation of bagasse takes place in two stages: volatilization and carbonization. The reaction rate, activation energy, entropy change, enthalpy change, and Gibbs free energy for the two thermal stages were calculated. The results indicated that activation energy for the volatilization stage is higher than that of decarbonization stage, and that both the rate constant and activation energy for combustion are higher than those of pyrolysis. © 1996 John Wiley & Sons, Inc.  相似文献   
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