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241.
In spite of significant improvements in video data retrieval, a system has not yet been developed that can adequately respond to a user’s query. Typically, the user has to refine the query many times and view query results until eventually the expected videos are retrieved from the database. The complexity of video data and questionable query structuring by the user aggravates the retrieval process. Most previous research in this area has focused on retrieval based on low-level features. Managing imprecise queries using semantic (high-level) content is no easier than queries based on low-level features due to the absence of a proper continuous distance function. We provide a method to help users search for clips and videos of interest in video databases. The video clips are classified as interesting and uninteresting based on user browsing. The attribute values of clips are classified by commonality, presence, and frequency within each of the two groups to be used in computing the relevance of each clip to the user’s query. In this paper, we provide an intelligent query structuring system, called I-Quest, to rank clips based on user browsing feedback, where a template generation from the set of interesting and uninteresting sets is impossible or yields poor results.
Ramazan Savaş Aygün (Corresponding author)Email:
  相似文献   
242.
A theory has been developed to simulate spin-wave resonance (SWR) modes in the multilayer systems consisting of alternate magnetic and nonmagnetic layers. An equation of motion of magnetization with Gilbert-type damping parameter for simulating SWR modes was used. It has been realized that the theory developed for the magnetic multilayer films is suitable to study the spin dynamics and extract various magnetic parameters. It has been shown that SWR modes strongly depend on an effective magnetic anisotropy constant (K eff), interlayer exchange coupling constant (A 12) and effective magnetization (M eff). The nature of the effective magnetic anisotropy and interlayer exchange coupling constants has been investigated by using the developed SWR theory in detail. The separation between optic and acoustic modes strongly depends on the magnitude of the interlayer exchange coupling constant, whereas the relative position of the acoustic and optic modes depends on the sign of \(A_{12}\). With increasing the interlayer exchange coupling constant, the resonance field of the optic mode decreases (increases) for ferromagnetic (antiferromagnetic) coupling. When the effective magnetic anisotropy constant increases, the resonance field of the acoustic and optic modes increases for both the ferromagnetic and antiferromagnetic couplings. The increasing of the effective magnetization results in decreasing of the resonance field of SWR mode at parallel geometry, whereas that of SWR mode increases at the perpendicular geometry. The results are compatible to the other theories and experimental results.  相似文献   
243.
This letter presents the experimental results of a novel planar antenna design which is synthesized using simplified composite left/right‐handed transmission‐line (SCRLH‐TL), which is a version of a conventional composite left/right handed‐transmission‐lines (CRLH‐TL), however, with the omission of shunt‐inductance in the unit‐cell. SCRLH‐TL exhibits a right‐handed response with nonlinear dispersion properties and a smooth Bloch‐impedance distribution. Arranged within the inner slot of the antenna are three smaller rectangular patch radiators. Each patch radiator is embedded with an E‐shaped notch, and located in the antenna conductor is a larger E‐shaped notch next to the 50‐Ω termination. The E‐shaped notches constitute SCRLH‐TL property. The gap in the slot between the smaller patches and the conductor next to the larger E‐shaped notch determines the impedance bandwidth of the antenna. The dimensions of the smaller patches determine the radiation characteristics of the antenna. The antenna is excited using a conductor‐backed coplanar waveguide transmission‐line. The antenna covers a bandwidth of 7.3 GHz between 0.7 GHz and 8GHz, which corresponds to 167.81%. In this band, the antenna resonates at 4.75 GHz and 7 GHz; the gain and radiation efficiency at these frequencies are 4 dBi—80% and 3.6 dBi—73%, respectively. The antenna's performance was validated through measurement. The antenna has dimensions of 0.0504λ0 × 0.0462λ0 × 0.0018λ0, where λ0 is free‐space wavelength at 700 MHz. © 2016 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:217–225, 2016.  相似文献   
244.
Matrix converter is an energy conversion device which directly connects a three-phase voltage source to a three-phase load without dc-link components. Therefore, the output of the matrix converter is directly affected by the disturbance or imbalance in the input voltages. Many researchers have made an effort to overcome this problem in recent years. In this paper, the behaviors of the matrix converter controlled with the optimum-amplitude Venturini method are investigated and a novel compensation technique based on fuzzy logic controller is proposed to eliminate the undesirable influences of the input voltage under the distorted input voltage conditions. The proposed technique is based on closed loop control of the three-phase output current to enhance the output performance of the matrix converter. The mathematical model of the proposed system is developed. The simulation of the development model is performed in Matlab&Simulink. Some results demonstrating validity of the proposed compensation technique are presented.  相似文献   
245.
Peroxidase enzyme was purified for the first time from white cabbage (Brassica oleracea var. capitata f. alba) in a single step using affinity chromatography and some biochemical characteristics of the purified enzyme were determined. The peroxidase was purified 24.7-fold with an overall recovery of 4.3% and a specific activity of 964.5. The molecular weight of the purified peroxidase was approximately 73.2 kDa as calculated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and it showed maximum activity at pH 6.5 and 30°C. For the guaiacol substrate, the KM and Vmax values were found as 3.19 mM and 0.2 EU/mL, respectively. Additionally, the IC50 and Ki values were determined as 0.517 and 0.994 ± 0.453 mM, respectively, for 4-aminobenzohydrazide. 4-amino benzohydrazide showed non-competitive inhibition.  相似文献   
246.
Neopterin is a diagnostic or a prognostic biomarker for several pathologies including renal diseases. However, the association between neopterin status and causative main reasons such as diabetes and hypertension for renal disease remains unclear. The aim of the study was to evaluate neopterin levels in diabetes and hypertension patients treated with/without hemodialysis. According to primary renal disorders, the patients undergoing hemodialysis were classified into 4 groups as diabetic nephropathy, hypertensive nephropathy, reflux nephropathy or interstitial nephritis, and others. The controls consisted of healthy subjects, hypertensive subjects, and diabetic individuals without any renal disorder. In the study, both urinary and serum neopterin levels were measured using high performance liquid chromatography and enzyme‐linked immunosorbant assay in patients undergoing regular hemodialysis therapy (n=71). The effects of the duration of hemodialysis and treatment of erythropoietin and/or iron on neopterin levels were also evaluated. Neopterin levels were found to be higher in hemodialysis patients than in the healthy controls (P<0.05). A significant difference in neopterin levels was also found between diabetic control patients and diabetic nephropathy patients (P<0.05). A similar significant difference was detected in neopterin levels between hypertensive patients with/without nephropathy (P<0.05). Neopterin may be an early critical marker for progression of nephropathy in diabetic and hypertensive patients in early stages.  相似文献   
247.
In daily life, expanded polystyrene foams (EPS) are widely used as packaging material, construction material, and in household appliances as well as many others. On the other hand, waste EPS has caused lots of environmental pollutions because it cannot be decomposed in nature. Utilization of waste EPS in concrete technology is more common. In this study, a new recycling process developed of the waste EPS foams by using heat treatment. Its characters and process are described in this paper, as well as its experimental system. This technique reduces the volume of waste EPS about 20 times of the original. Before the heat treatment, the average density, thermal conductivity and compressive strength of waste EPS foams were 10 kg/m3, 0.0368 W/mK, and 0.12 MPa, respectively. The best result of modification was determined at 130 °C and 15 min. After the modification, density, thermal conductivity and compressive strength of waste EPS, increased to 217 kg/m3, 0.0555 W/mK and 8.29 MPa, respectively. This new material, which is obtained after the heat treatment, is called modified waste EPS (MEPS).  相似文献   
248.
2-Aminothiazole (2AT) was electrochemically polymerized on a Pt electrode using cyclic voltammetry (CV) technique from 0.01 M monomer containing 0.3 M ammonium oxalate solution. The high quality poly-2-aminothiazole (pAT) films with a light-brownish color were obtained on the Pt surface. The electrochemical behavior of the pAT-coated Pt electrode (Pt/pAT) was investigated in monomer-free 0.3 M ammonium oxalate solution by CV technique. The chemical structure characterization was investigated by UV–vis spectroscopy (UV–vis) and Fourier transform infrared spectroscopy (FTIR) techniques. The surface morphology of the polymer film was examined by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The surface morphology studies showed that, a homogeneous and compact film was formed on the Pt surface. Further, thermogravimetric analysis (TGA), differential thermal analysis (DTA) and differential scanning calorimetry (DSC) techniques were used to investigate the thermal properties of the polymer film. It was found that the thermal stability of the pAT film is relatively high. The solubility of the pAT was tested in common organic solvents as well as in acidic and basic solutions.  相似文献   
249.
Phenol based novalac, resol and the blend of both resins were used as binders in briquette production from coke breeze. The effects of the amount of catalyst on the tensile strength of the cured briquette were studied. The results obtained have indicated that the highest tensile strength could not be attained unless the blend of novalac and resol was used as binder. The most suitable blend was the binder prepared from the hydrochloric acid catalyzed novalac of F/P = 0.5 and the N/P = 0.3 catalyzed resol of F/P = 2.0. When this blend was used as a binder the tensile strength of the cured briquettes did not drop even if they were carbonized at 470 °C and 570 °C. Their strengths at these carbonization temperatures were 67 MPa and 72 MPa respectively, and the rise in the temperature resulted in some increase in their strength. These results show the fact that as the formed coke briquettes descends from the top of the blast furnace, the rise in temperature will not deteriorate their strength; it will probably improve their properties. Therefore, only curing at 200 °C for 2 h will be sufficient for the briquettes to be used as substitute for metallurgical coke in the blast furnace.  相似文献   
250.
This paper reexamines the inter-temporal link between energy consumption and income in six developing countries with diverse economic backgrounds and energy statistics, in a production function framework. We employ the generalized variance decompositions and generalized impulse response techniques to see if the growth of income and energy consumption contains considerable information to predict each other. In all countries, energy appears as an essential factor of production. Results indicate that energy may be a relatively more important input than labor and/or capital in some countries. Hence, neutrality of energy does not seem to hold.  相似文献   
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