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61.

At lower noise levels, the majority of filter-based impulse noise removal approaches outperform each other. The purpose of this paper is to design an efficient adaptive pulse coupled neural network (APCNN) technique with improved alpha guided grey wolf optimization (IAgGWO) for the elimination of high-density impulse noise. This noise reduction technique is divided into two stages: the detection of noisy pixels and the replacement of a noisy pixel with a data pixel. The IAgGWO technique is utilised to isolate the optimal values for identifying impulse noisy pixels, and the APCNN filtering technique is used to supplant them. This technique provides more accurate and clean filtered images while preserving critical edge pixel information. To demonstrate the IAgGWO-APCNN strategy's efficacy, various degrees of impulse noise were applied to the image and tested. With PSNR of 42 percent, SSIM of 99 percentand STD of 40 percent on satellite pictures, the suggested noise removal model has proved its unshakable consistency in terms of both qualitative and quantitative assessment.

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62.
Our aim is to study the heat transfer processes in a cooling circuit. In this project, a mild steel plate of 1.1 m?×?1.1 m?×?6 mm dimensions is used. Square pipes are embedded in a liner plate, through which the water is circulated to remove heat from the reactor vault. To improve the contact between the pipes and the liner, the pipes are welded to the liner throughout their length. A heater plate simulating main vessel was placed, and the electrical heaters were laid all over the inner surface of main vessel. The square pipes were made to let the water flow through them, and the flow rate is set using a flow meter and this water is heated by convection and it is condensed by passing through a heat exchanger. Thermocouples are fixed at different locations of cooling pipes, the liner and the water inlet/outlet.  相似文献   
63.
The interaction between the amphiphilic drug amitriptyline hydrochloride (AMT) and the nonionic surfactants used in drug delivery has been investigated. Herein, we report the micellization behavior of AMT in presence of ethoxylated alkyl phenols in aqueous medium and the clouding phenomenon in the absence and presence of different nonionic surfactants in buffer solution. The values of critical micelle concentration (CMC) of AMT obtained using the conductivity method, decrease as nonionic surfactant concentration increases. With an increase in temperature, the CMC first increases and then decreases. At 303.15 K, the maximum CMC values were obtained with or without nonionic surfactant. The results obtained indicate attractive interactions (synergism) between the two mixing amphiphiles in solution. The experimentally obtained critical micelle concentration (CMC) values are always lower than ideal CMC values. Micellar mole fraction (X1) values, calculated by different proposed models, show the contribution of nonionic surfactant concentration. At a fixed drug concentration (50 mmol kg?1) and pH (=6.7) nonionic surfactants show continuous increase in cloud point (CP). Increase in drug concentration and pH, in the presence of fixed amounts of nonionic surfactant, increases and decreases the CP, respectively.  相似文献   
64.
A comparative study was carried out on the development of ultrafine-grained dual-phase (DP) (ferrite–martensite) structures in a low-carbon microalloyed steel processed using two thermomechanical processing routes, (i) intercritical deformation and (ii) warm-deformation and intercritical annealing. The samples were deformed using Gleeble3500® simulator, maintaining a constant total strain (ε = 1) and strain rate ( $ \dot \varepsilon $  = 1/s). Evolution of microstructure and micro-texture was investigated by SEM, TEM, and EBSD. Ultrafine-grained DP structures could be formed by careful selection of deformation temperature, T def (for intercritical deformation) or annealing temperature, T anneal (for warm-deformation and annealing). Overall, the ferrite grain sizes ranged from 1.5 to 4.0 μm, and the sizes and fractions of the uniformly distributed fine-martensitic islands ranged from 1.5 to 3.0 μm and 15 to 45 pct, respectively. Dynamic strain-induced austenite-to-ferrite transformation followed by continuous (dynamic) recrystallization of the ferrite dictated the grain refinement during intercritical deformation, while, continuous (static) recrystallization by pronounced recovery dictated the grain refinement during the warm-deformation and the annealing. Regarding intercritical deformation, the samples cooled to T def indicated finer grain size compared with the samples heated to T def, which are explained in terms of the effects of strain partitioning on the ferrite and the heating during deformation. Alpha-fiber components dominated the texture in all the samples, and the fraction of high-angle boundaries (with >15 deg misorientation) increased with the increasing T def or T anneal, depending on the processing schedule. Fine carbide particles, microalloyed precipitates and austenitic islands played important roles in defining the mechanism of grain refinement that involved retarding conventional ferrite recrystallization and ferrite grain growth. With regard to the intercritical deformation, warm-deformation followed by annealing is a simpler process to control in the rolling mill; however, the need for high-power rolling mill and controlled annealing facility imposes industrial challenges.  相似文献   
65.
We define the new idea of blind image repair as a process of correcting one or more different and unknown types of distortions afflicting an image. These distortions could introduce linear or non-linear degradations, compression artifacts, noise, etc., or combinations of these. Thus the concept encompasses denoising, deblurring, deblocking, deringing, and other post-acquisition image improvement processes that address distortions. The problem is distortion-blind when the natures of the distortion processes are unknown prior to analyzing the image. Towards solving this problem, we describe a new framework for repairing an image that has undergone an unknown set of distortions, based on identifying the distortion(s) present in the image (if any) and applying possibly multiple distortion-specific image repair algorithms. Our philosophy is based on the principle that the task of general purpose image repair is one of agglomeration, i.e., the algorithm should embody multiple high-performing distortion-specific repair modules such that seamless general purpose image repair is achieved. Our proposed framework – the GEneral-purpose No-reference Image Improver (GENII) – enables the design of algorithms that are blind to distortion type as well as to distortion parameters, and only requires as input the distorted image to be repaired. The GENII framework is modular and easily extensible to image repair problems beyond those considered here. GENII operates by using natural scene statistic models to identify distortion, to perceptually optimize the distortion parameter(s), to assess the quality of the intermediate repaired images, and to perceptually optimize the repair processes. We explain the general purpose image repair framework and one specific realization, dubbed GENII-1, which assumes that the image has been affected by one or more of four possible distortion types.The performance of GENII-1 is evaluated on 4000 distorted images, and shown to deliver substantial improvements in both quantitative and qualitative visual quality.  相似文献   
66.
Hot forming is an important forming method for production of small and medium sized single-piece pressure vessel dish ends. Thinning of the blank material with increased degree of forming is quite obvious. Present work shows finite element (FE) analysis of hot forming of single-piece hemispherical dish end (SPHDE) for predicting maximum thinning of blank during forming. Thinning analysis is performed for SPHDE of two different ferrous material grades SA-387 Gr22 and SA-516 as per ASME, Section II, Part A (2004). Percentage thinning results of FE analysis are verified with the practical material thinning data. Based on the thinning analysis, empirical relation for calculation of percentage thinning as a function of different dish ends′ geometry parameters is proposed. Empirically predicted percentage thinning is observed to be in good agreement with practical and FE simulation results. Thinning results obtained based on proposed FE simulation and empirical model can be helpful to design engineer in selecting thickness of developed blank considering thinning allowance for hot forming of SPHDE. Thinning analysis data can be used for optimizing the dish end geometrical parameters for minimum thinning during forming.  相似文献   
67.
Metallurgical and Materials Transactions A - Two different high-strength B-containing microalloyed steel strips produced in industrial processing conditions, one treated with Ti and the other...  相似文献   
68.
It is necessary to synthesize new material for the advancements of the technology. In this study, new and novel poly(2-anisidine)@zirconium tungstate(P2A/ZrW_2O_8) was synthesized by simple so-gel method. Physicochemical characterization of P2A/ZrW_2O_8 was done by thermogravimetric analysis(TGA), scanning electron microscopy(SEM), X-ray powder diffraction(XRD), Fourier transform infrared spectroscopy(FTIR), ion exchange and simultaneous four probe dc conductivity studies. The conductivity study revealed its highly semiconducting nature, in the range of 10~(-1)–10~(-2) S·cm~(-1). Ion-exchange capabilities of the composite make it applicable for cation-exchange studies. The result of distribution studies(Kd) revealed its selectivity towards Cd~(2+) compared to other metal ions. This property of the composite was utilized for designing Cd~(2+) selective membrane electrode. Several important physical parameters of the ion-selective electrode were determined, such as Nernstian slope(32.32 mV·decade~(-1)), working pH range was 2.0–4.0 and response time was found ~ 17 s.The analytical utility of this wave like composite membrane electrode was as, indicator electrode in various potentiometric titrations.  相似文献   
69.
70.
This research evaluated an offline vacuum decay leak detection system for 1775-ml polyethylene terephthalate (PET) bottles. These bottles were filled with water and pulped and unpulped orange juice and induction sealed with an aluminum liner and an outer 38-mm continuous thread polypropylene cap. The objectives of this study were to evaluate (i) minimum leak size sensitivity of the instrument; (ii) ability to identify weak but nonleaking seals; (iii) effect of varying fill heights on the equipment's sensitivity; and (iv) percentage of false-positive and negative results likely to be obtained during a normal test run. To meet these objectives, leaks 5, 10, 15, 20, 30, 40, and 50 microm were created in the PET bottles. A second set of bottles was induction sealed at high voltage and 1, 1.5, 2, 2.5, 3, 3.5, and 4 s of dwell time. A third set of bottles with good seals was filled with differing headspace measurements of brimful, 1, 2, 3, 4, and 5 cm. After optimizing the equipment, leak tests on random sets of leaking and nonleaking bottles showed 0.0% false-positive and 0.0% negative identifications. Results showed 5-microm minimum leak size detection for bottles filled with all products. Optimum seal conditions were >2 but <3 s at high voltage. Product fill heights >2 to < or =3 cm did not affect the efficiency of the equipment. These results show that this vacuum decay system has potential for use in identifying leaks in PET bottles used for food packaging.  相似文献   
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