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1.
Working with survivors of political torture and war trauma can trigger strong emotional responses in the therapist. As more survivors seek treatment, it is essential to identify and develop robust support systems for therapists who help their clients confront nearly unspeakable experiences. The emotional reactions of 6 psychotherapists who worked with traumatized survivors in a refugee treatment center were explored. The psychotherapists' reactions were compared with those of therapists who worked in different treatment settings with other presenting problems. The results of the study show that the strong level of responsibility therapists feel for their traumatized clients may hide an emotional strain and may lead to burnout. Suggestions are offered for supporting therapists in this difficult but important work. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
Parameter extraction for bipolar transistors   总被引:1,自引:0,他引:1  
Different methods of extracting the DC Gummel-Poon bipolar transistor model parameters are reviewed. First the shortcomings of the classical extraction schemes for the intrinsic model are presented together with some improved procedures. Finally the extraction of the series resistances is addressed.  相似文献   
3.
The effect of 2 months of treatment with the oral growth hormone (GH) secretagogue MK-677 on markers of bone metabolism was determined in healthy obese male subjects. This was a randomized, double-blind, parallel, placebo-controlled study. Twenty-four healthy obese males, 19-49 years of age, with body mass index > 30 kg/m2 were treated with MK-677 (25 mg/day; n = 12) or placebo (n = 12) for 8 weeks. MK-677 increased markers of bone formation; a 23% increase in the carboxy-terminal propeptide of type I procollagen levels and a 28% increase in procollagen III peptide levels were seen with as little as 2 weeks of MK-677 treatment (p < 0.01 and p = 0.001 vs. placebo, respectively) while a 15% increase in serum levels of osteocalcin was not detected until 8 weeks of treatment (p < 0.01 vs. placebo). Markers of bone resorption were induced within 2 weeks of treatment with MK-677; serum levels of the carboxy-terminal cross-linked telopeptide of type I collagen were increased 26% at 8 weeks (p = 0.001 vs. placebo), and urine hydroxyproline/creatinine and calcium/creatinine ratios at 8 weeks were increased by 23% (p < 0.05 vs. placebo) and 46% (p < 0.05 vs placebo), respectively, MK-677 increased serum insulin-like growth factor binding protein-5 (IGFBP-5) by 43-44% after 2-8 weeks of treatment (p < 0.01 vs. placebo). Serum IGFBP-4 was increased by 25% after 2 weeks of treatment (p < 0.001 vs. placebo) but no significant change from baseline was observed after 8 weeks of treatment. Plasma interleukin-6 was not significantly changed by active treatment. In conclusion, short-term treatment of healthy obese male volunteers with the GH secretagogue MK-677 increases markers of both bone resorption and formation. Large increases in serum levels of IGF-1 and IGFBP-5 and a transient increase in serum IGFBP-4 were found. Future long-term studies are needed to investigate if prolonged treatment with MK-677 increases bone mass.  相似文献   
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We have performed an extended replication of the Porter-Votta-Basili experiment comparing the Scenario method and the Checklist method for inspecting requirements specifications using identical instruments. The experiment has been conducted in our educational context represented by a more general definition of a defect compared to the original defect list. Our study involving 24 undergraduate students manipulated three independent variables: detection method, requirements specification, and the order of the inspections. The dependent variable measured is the defect detection rate. We found the requirements specification inspected and not the detection method to be the most probable explanation for the variance in defect detection rate. This suggests that it is important to gather knowledge of how a requirements specification can convey an understandable view of the product and to adapt inspection methods accordingly. Contrary to the original experiment, we can not significantly support the superiority of the Scenario method. This is in accordance with a replication conducted by Fusaro, Lanubile and Visaggio, and might be explained by the lack of individual defect detection skill of our less experienced subjects.  相似文献   
6.
Flow problems with moving boundaries and interfaces include fluid–structure interaction (FSI) and a number of other classes of problems, have an important place in engineering analysis and design, and offer some formidable computational challenges. Bringing solution and analysis to them motivated the Deforming-Spatial-Domain/Stabilized Space–Time (DSD/SST) method and also the variational multiscale version of the Arbitrary Lagrangian–Eulerian method (ALE-VMS). Since their inception, these two methods and their improved versions have been applied to a diverse set of challenging problems with a common core computational technology need. The classes of problems solved include free-surface and two-fluid flows, fluid–object and fluid–particle interaction, FSI, and flows with solid surfaces in fast, linear or rotational relative motion. Some of the most challenging FSI problems, including parachute FSI, wind-turbine FSI and arterial FSI, are being solved and analyzed with the DSD/SST and ALE-VMS methods as core technologies. Better accuracy and improved turbulence modeling were brought with the recently-introduced VMS version of the DSD/SST method, which is called DSD/SST-VMST (also ST-VMS). In specific classes of problems, such as parachute FSI, arterial FSI, ship hydrodynamics, fluid–object interaction, aerodynamics of flapping wings, and wind-turbine aerodynamics and FSI, the scope and accuracy of the FSI modeling were increased with the special ALE-VMS and ST FSI techniques targeting each of those classes of problems. This article provides an overview of the core ALE-VMS and ST FSI techniques, their recent versions, and the special ALE-VMS and ST FSI techniques. It also provides examples of challenging problems solved and analyzed in parachute FSI, arterial FSI, ship hydrodynamics, aerodynamics of flapping wings, wind-turbine aerodynamics, and bridge-deck aerodynamics and vortex-induced vibrations.  相似文献   
7.
Steady-state compressive creep rate of La0.5Sr0.5Fe0.5Co0.5O3−δ (LSFC) and La0.5Sr0.5CoO3−δ (LSC) is reported in the temperature region 900°–1050°C and stress range 5–28 MPa. The stress exponents for the two materials were 1.71±0.18 and 1.24±0.15, respectively. The activation energy for creep was considerably higher for LSC (619±56 kJ/mol) than for LSFC (392±28 kJ/mol). The grain size exponent for LSC was 1.28±0.14. Considerably higher creep rates were observed for both materials in N2 compared with air. Relaxation by creep of chemical-induced stresses in oxygen-permeable membranes is addressed, especially at low partial pressure of oxygen.  相似文献   
8.
Youmans RJ  Ohlsson S 《Ergonomics》2008,51(4):441-475
The operation of machines typically requires attention to instruments that signal the state of the machine. One safeguard against primary instrument malfunction is to provide backup instruments, but this works only if the operators react to malfunction by switching attention to the backups. Little is known about the effect of negative outcomes or feedback on allocation of attention to backup instruments. Four experiments demonstrated that prior practice causes operators of a simulated machine to adapt to instrument malfunction by changing to a suboptimal decision rule rather than by reallocating attention to a different set of instruments. This fallacy appears linked to the operators' failures to notice feedback that they should switch during the simulations and operators' failures to correctly interpret outcome feedback following the simulations. The results raise theoretical questions and warn interface designers not to overrate backup instruments.  相似文献   
9.
Abstract— The primary goal of this study was to find a measurement method for motion blur which is easy to carry out and gives results that can be reproduced from one lab to another. This method should be able to also take into account methods for reduction of motion blur such as backlight flashing. Two methods have been compared. The first method uses a high‐speed camera that permits us to directly picture the blurred‐edge profile. The second one exploits the mathematical analysis of the motion‐blur formation to construct the blurred‐edge profile from the temporal step response. Measurement results and method proposals are given and discussed.  相似文献   
10.
This article investigates the relationship between the control situation framework, as presented by Bjørkli et al. (Cogn Technol Work 9:67–80, 2007), and observed operator action and communication in high-speed craft operation in the Norwegian Royal Navy. The reported data include two series of events during sailing in the Norwegian archipelago where uncertainty of ship position, challenges of manoeuvring and navigation strategies are addressed. The results indicate that the navigators perform actions and communicate in accordance with the key features of the control situation framework, and thus adapt to the interrelation between control possibilities and control requirements. The navigators were guided by explicit knowledge of the functional characteristics of psychical and temporal dynamics, which were actualized in manoeuvring. It indicates that the control situation framework can be used to describe the models the operators use.  相似文献   
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