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21.
When heavy-duty commercial vehicles (HDCVs) must engage in emergency braking, uncertain conditions such as the brake pressure and road profile variations will inevitably affect braking control. To minimize these uncertainties, we propose a combined longitudinal and lateral controller method based on stochastic model predictive control (SMPC) that is achieved via Chebyshev–Cantelli inequality. In our method, SMPC calculates braking control inputs based on a finite time prediction that is achieved by solving stochastic programming elements, including chance constraints. To accomplish this, SMPC explicitly describes the probabilistic uncertainties to be used when designing a robust control strategy. The main contribution of this paper is the proposal of a braking control formulation that is robust against probabilistic friction circle uncertainty effects. More specifically, the use of Chebyshev–Cantelli inequality suppresses road profile influences, which have characteristics that are different from the Gaussian distribution, thereby improving both braking robustness and control performance against statistical disturbances.Additionally, since theKalman filtering (KF) algorithm is used to obtain the expectation and covariance used for calculating deterministic transformed chance constraints, the SMPC is reformulated as a KF embedded deterministic MPC. Herein, the effectiveness of our proposed method is verified via a MATLAB/Simulink and TruckSim co-simulation.  相似文献   
22.
The water-absorption properties of various vehicles were evaluated in rats whose stratum corneum had been stripped off over the application site. Polyethylene glycol (PEG) applied to the site effectively absorbed the exudate, but other applied ointments absorbed little exudate or water. By the PEG ointment, the exudate was absorbed continuously and extensively, and a linear relationship was obtained between the amount of water absorbed and the square root of time. To establish an acceptable alternative in vitro method for the design of a suitable ointment for treating skin ulcers with exudate, in vitro evaluations were performed by three methods: the Franz cell method, the cellulose membrane diffusion method and the spontaneous water uptake method. The membrane diffusion method, and the spontaneous water uptake method appeared to be acceptable alternatives to the in vivo method in evaluating the water absorption of ointments. It is a simple and useful method for preliminary formulation studies of ointments for the treatment of skin ulcers with exudate.  相似文献   
23.
ELID-lap grinding is a method of constant pressure grinding which utilizes an electrically conductive wheel and the electrolytic in-process dressing (ELID) method. This method has the advantage of using micro grain-wheels above #10 000 and also, through simple modification, can be used on existing lap machines. To find the characteristics of metal-resin bonded wheels developed for ELID-lap grinding, experiments on the grinding of brittle materials were performed using wheels with a variety of grain diameters. The wheels used in the experiments were #8000, #120 000 and #3 000 000 metal-resin bonded diamond wheels (#8000 MRB-D, #120 000 MRB-D and #3 000 000 MRB-D wheels). The workpieces were silicon and glass. The results of the experiments showed that stable grinding can be achieved with the #8000 to #3 000 000 MRB-D wheels. With the #3 000 000 MRB-D wheel, very smooth surface finishes were obtained for both silicon (PV 2.8 nm) and glass (PV 2.5 nm). Atomic Force Microscope (AFM) and Scanning Electron Microscope (SEM) observations indicated these surfaces to be very smooth in the order of several nanometers, obtained by mechanical removal using an ultrafine wheel.  相似文献   
24.
The microstructures and mechanical properties of binary and ternary Cr-based alloys containing Nb, Zr, or both Nb and Zr, have been studied in both the as-cast and annealed conditions. The level of alloying in each instance was targeted to lie below, or approximately at, the maximum solubility in chromium. The as-cast microstructures of these alloys consisted of Cr-rich solid solution surrounded by small amounts of interdendritic Cr–Cr2X eutectic structure. Annealing at 1473 K resulted in solid-state precipitation of the Cr2X Laves phase in the Cr–Nb and Cr–Nb–Zr alloys, but not in the Cr–Zr alloys. The binary Cr2Nb phase consisted of an extensively twinned ({111}<112> twins) C15 structure whereas the presence of Zr modifies its appearance substantially; the twinned C15 structure persists. Oxides were occasionally present and their compositions were qualitatively determined. Vickers hardness primarily depended upon the volume fraction of the Cr2X Laves phase present. Age hardening due to solid-state precipitation of Cr2X Laves phase within the Cr-rich matrix was observed in the Nb-containing alloys. The room temperature bend strength of the alloys was strongly affected by the presence of grain-boundary Cr2X phase. It is considered that porosity as well as oxides in the alloys also lowers their bend strength.  相似文献   
25.
This paper proposes a unified approach to linear controller synthesis that employs various LMI conditions to represent control specifications. We define a comprehensive class of LMIs and consider a general synthesis problem described by any LMI of the class. We show a procedure that reduces the synthesis problem, which is a BMI problem, to solving a certain LMI. The derived LMI condition is equivalent to the original BMI condition and also gives a convex parametrization of all the controllers that solve the synthesis problem. The class contains many of widely-known LMIs (for H norm, H2 norm, etc.), and hence the solution of this paper unifies design methods that have been proposed depending on each LMI. Further, the class also provides LMIs for multi-objective performance measures, which enable a new formulation of controller design through convex optimization. © 1998 John Wiley & Sons, Ltd.  相似文献   
26.
Dual two-phase intermetallic alloys composed of geometrically close-packed (GCP) structures of Ni3Al (L12) and Ni3V (D022) containing Nb were investigated in terms of microstructural evolution during low-temperature annealing (aging) and the related mechanical properties. The eutectoid region, i.e. the prior Al phase (Ni solid solution) is composed of the lamellar-like structure consisting of Ni3Al (L12) and Ni3V (D022) even at an early aging stage, and then coarsen with increasing aging time. The lamellar-like structure tend to align along direction and on {001} plane in the prior A1 phase (or the L12 phase). In a wide range of temperature, the dual two-phase intermetallic alloys showed high yield and tensile strength, and also reasonable tensile ductility, accompanied with ductile fracture mode. The observed mechanical properties were less sensitive to the microstructural evolution during low-temperature annealing (aging), meaning that the present dual two-phase intermetallic alloy is promising for a new type of high-temperature structural material.  相似文献   
27.
In this paper, we present novel organic light‐emitting diode (OLED) display panel compensation technologies for large‐sized ultra‐high‐definition OLED TVs considering variations of threshold voltage, mobility, channel size, OLED efficiency, and OLED uniformity. Using these technologies, we have successfully launched 55‐, 65‐ and 77‐in. ultra‐high‐definition OLED TVs.  相似文献   
28.
The incidence of tuberculosis is rising in the United States. Similarly, the incidence of pulmonary tuberculosis in Taiwan is increasing, but that of large bowel tuberculosis in this region has not been reported. The purpose of this study was to investigate the changing disease pattern and to determine some possible surgical prognostic factors for large bowel tuberculosis. Seventy cases of large bowel tuberculosis treated at our institute during the period 1965-1995 were reviewed and analyzed. A steady decline in the case number of large bowel tuberculosis were noted from 1975, but there seems to be a slight increase in cases since 1990. The average age of these patients was 65.1 years, and none had human immunodeficiency virus infection. The ileocecum is the most common region of involvement. Of these 70 patients, 59 had not been definitively diagnosed until surgery. Active pulmonary tuberculosis was found in 18 patients (25.7%). The incidence of postoperative pulmonary complications was higher in patients with active pulmonary tuberculosis or disseminating large bowel tuberculosis. Postoperative abdominal complications, including intestinal obstruction, abdominal cutaneous fistula, and wound infection, were seen in 13 patients, none of whom had active pulmonary tuberculosis. Although the incidence of tuberculosis has been reduced for years, it is now rising. Physicians should bear in mind the possibility of large bowel tuberculosis in patients with intestinal obstruction without specific origin. Postoperative respiratory care is important for patients with pulmonary tuberculosis, with either active or disseminating lesions.  相似文献   
29.
We have reported previously that loop diuretics, especially azosemide and ethacrynic acid, may act not only on the AVP receptor site, but also on the post-AVP receptor site in rat renal tubular basolateral membranes. The purpose of this study was to examine whether loop diuretics (furosemide, azosemide, ethacrynic acid) affect the post-AVP receptor components, using GTP-gamma S, forskolin and cholera toxin as tools acting distal to the receptor. Adenylate cyclase activity stimulated by 10(-9)M AVP was inhibited more potently by azosemide and ethacrynic acid than by furosemide at the concentration of 10(-3) M. Azosemide and ethacrynic acid at concentrations above 10(-4) M also significantly decreased the enzyme activity that was stimulated by 10(-7) M GTP-gamma S and 10(-5)M forskolin, while significant inhibition by furosemide was observed only at 10(-3)M. In addition, the inhibitory effect of these loop diuretics on cholera toxin-stimulated enzyme activity was almost similar to the results observed in AVP-, GTP-gamma S- or forskolin-stimulated the enzyme activity. From these results, we conclude that loop diuretics, especially azosemide and ethacrynic acid, directly affect adenylate cyclase in part as well as the AVP receptor site.  相似文献   
30.
Ultra-fast microwave sintering in a multi-mode domestic microwave oven with selective susceptor and spacer has been proved to be an effective and facile method in the manufacturing of anode support solid oxide fuel cell (SOFC). Two anode support SOFCs were fabricated by using ultra-fast microwave sintering and conventional thermal sintering techniques, separately. The performances of the two cells were measured and compared in a temperature range of 700-800 °C. The microstructures of the two cells after the measurements were compared qualitatively based on SEM images. FIB-SEM technique was used to reconstruct the 3-D microstructure of both anode and cathode. The quantitative comparison of 3-D reconstructions shows the application potential and the advantages of microwave technique in SOFCs manufacturing.  相似文献   
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