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31.
Diabetic Retinopathy (DR) has become a widespread illness among diabetics across the globe. Retinal fundus images are generally used by physicians to detect and classify the stages of DR. Since manual examination of DR images is a time-consuming process with the risks of biased results, automated tools using Artificial Intelligence (AI) to diagnose the disease have become essential. In this view, the current study develops an Optimal Deep Learning-enabled Fusion-based Diabetic Retinopathy Detection and Classification (ODL-FDRDC) technique. The intention of the proposed ODL-FDRDC technique is to identify DR and categorize its different grades using retinal fundus images. In addition, ODL-FDRDC technique involves region growing segmentation technique to determine the infected regions. Moreover, the fusion of two DL models namely, CapsNet and MobileNet is used for feature extraction. Further, the hyperparameter tuning of these models is also performed via Coyote Optimization Algorithm (COA). Gated Recurrent Unit (GRU) is also utilized to identify DR. The experimental results of the analysis, accomplished by ODL-FDRDC technique against benchmark DR dataset, established the supremacy of the technique over existing methodologies under different measures.  相似文献   
32.
Prevention of cervical cancer becomes essential and is carried out by the use of Pap smear images. Pap smear test analysis is laborious and tiresome work performed visually using a cytopathologist. Therefore, automated cervical cancer diagnosis using automated methods are necessary. This paper designs an optimal deep learning based Inception model for cervical cancer diagnosis (ODLIM-CCD) using pap smear images. The proposed ODLIM-CCD technique incorporates median filtering (MF) based pre-processing to discard the noise and Otsu model based segmentation process. Besides, deep convolutional neural network (DCNN) based Inception with Residual Network (ResNet) v2 model is utilized for deriving the feature vectors. Moreover, swallow swarm optimization (SSO) based hyperparameter tuning process is carried out for the optimal selection of hyperparameters. Finally, recurrent neural network (RNN) based classification process is done to determine the presence of cervical cancer or not. In order to showcase the improved diagnostic performance of the ODLIM-CCD technique, a series of simulations occur on benchmark test images and the outcomes highlighted the improved performance over the recent approaches with a superior accuracy of 0.9661.  相似文献   
33.
An explicit second-order finite-difference computer model was developed and optimized for solution of the Shallow Water Equations. The model was applied to the Feather River below the Oroville Dam and Thermalito Afterbay near Gridley, California. Two versions of the computer model were constructed to run on either Central Processing Units or Graphical Processing Units, utilizing Fortran, C, C++, and the NVIDIA Compute Unified Device Architecture (CUDA) parallel computing platform. The underlying algorithm utilizes a structured grid and is capable of handling the wetting and drying of cells. It was developed with view to maximizing stability while maintaining accuracy, and allowing for flexibility of the computational domain. Comparisons with analytical and observed results showed the proposed methodology to be robust, accurate, and efficient. The models were applied to a section of the Feather River where observations of flow depths and volumetric flow rates are available for multiple flood events. The domain surface was partially developed using high-resolution photogrammetric data obtained through use of unmanned aerial vehicles. Runtimes and results were compared to the United States Bureau of Reclamations’ implicit finite-volume numerical method and with field observation with generally good correspondence.  相似文献   
34.
The collision prevention system is one of most important research issues on vehicle safety technology. Sending worming messages within the right time and reliable transmission will get prevention of a possible vehicle accident. The communication standards of vehicular networks (VANET) are unable to guarantee the delivery of critical messages within tight deadlines. Indeed, the transmission collisions are handled with probabilistic manner that can reduce the transmission latency; however, it is inept to predict an upper bound value of this delay to verify the deadline. In this paper, we propose a medium access protocol that ensures the delivery of critical messages within a deadline. It is a hard real-time system with delay constant guarantee. We are focusing on improving the EDCA medium access protocol to prioritize critical messages and to get access to the transmission channel within a predictable communication delay. We create a new enhanced access protocol that is compatible with the IEEE 802.11p VANET standards and adapted to real-time communication requirements related to the vehicle collision avoidance problem.  相似文献   
35.
论述了建筑可持续发展的三个重要方面,即经济增长、社会进步和有效保护环境。具体包括有效地利用自然资源、减少能源消耗、减少废气排放量、减少浪费、更有效地利用土地、减少对施工现场的影响及创造更好的就业条件。着重讨论了钢结构的可持续发展。建造过程中采用钢结构的优势在于高速、预制、安全、较少的废弃物、具备工厂生产和现场施工条件。  相似文献   
36.
Improvements in methods for disinfecting fresh-cut cantaloupe could reduce spoilage losses and reduce the risk of foodborne illness from human pathogen contamination. The objective of this study was to investigate the feasibility of using hot-water treatment in combination with low-dose irradiation to reduce native microbial populations while maintaining the quality of fresh-cut cantaloupe. Whole cantaloupes were washed in tap water at 20 or 76 degrees C for 3 min. Fresh-cut cantaloupe cubes, prepared from the washed fruit, were then packaged in clamshell containers, and half the samples were exposed to 0.5 kGy of gamma radiation. Native microflora populations and sensory qualities were evaluated during the subsequent 7 days of storage at 4 degrees C. The hot-water surface pasteurization reduced the microflora population by 3.3 log on the surface of whole fruits, resulting in a lower microbial load on the fresh-cut cubes compared with cubes cut from fruit treated with cold water. Irradiation of cubes prepared from untreated fruit to an absorbed dose of 0.5 kGy achieved a low microbial load similar to that of cubes prepared from hot-water-treated fruit. The combination of the two treatments was able to further reduce the microflora population. During storage, the headspace atmosphere of the packages was not significantly influenced by any of the treatments. Color, titratable acidity, pH, ascorbic acid, firmness, and drip loss were not consistently affected by treatment with irradiation, hot water, or the combination of the two. Cubes prepared from hot-water-treated whole fruit had slightly lower soluble solids content. The combination of hot-water pasteurization of whole cantaloupe and low-dose irradiation of packaged fresh-cut melon can reduce the population of native microflora while maintaining the quality of this product.  相似文献   
37.
Narrow laser beams directed from aircraft may at times pass through the exhaust plume of the engines and potentially degrade some of the laser beam characteristics. This paper reports on controlled studies of laser beam deviation arising from propagation through turbulent hot gases, in a well-characterized laboratory burner, with conditions of relevance to aircraft engine exhaust plumes. The impact of the temperature, laser wavelength, and turbulence length scale on the beam deviation has been investigated. It was found that the laser beam displacement increases with the turbulent integral length scale. The effect of temperature on the laser beam angular deviation, σ, using two different laser wavelengths, namely 4.67 μm and 632.8 nm, was recorded. It was found that the beam deviation for both wavelengths may be semiempirically modeled using a single function of the form, σ=a(b+(1/T)(2))(-1), with two parameters only, a and b, where σ is in microradians and T is the temperature in °C.  相似文献   
38.
In this paper, we have discussed the application of new nonlinear recursive controllers on Josephson junction (JJ) chaotic systems. Controlling bifurcation as well as chaos has been rapidly advancing in the last decade. Thus, emphasis has been placed on control design techniques which result in prescribed nonlinear performance dynamics for practical controlled processes. This study has shown that a nonlinear recursive controller is effective in controlling an undesirable JJ chaotic behavior. In addition to that, the synchronization of two JJ chaotic nonlinear dynamical systems can be used to advantage in communication systems. In fact, communication security is promising through chaos. Using nonlinear control method, we have demonstrated that it is possible to achieve synchronization in electronic circuits such as JJ. The study showed the effectiveness of the designed controller in communication signal synchronization. For the purpose of verification and comparison, we designed a control signal based on master and slave concept.  相似文献   
39.
The problem of cross-flow forced heat transfer from a horizontal cylinder with multiple equally spaced low conductivity baffles on its outer surface was investigated numerically. The effect of several combinations of baffles and baffle heights on the average Nusselt number was studied over a wide range of Reynolds numbers. The results showed that there was an optimal number of baffles for a minimum Nusselt number for a given value of baffle height and Reynolds number. Short baffles slightly increased the Nusselt number at small Reynolds number values.  相似文献   
40.
In the present paper, a numerical investigation is conducted on film cooling performance from novel sister-shaped single-hole schemes. Based on the sister hole film cooling technique, shaped holes are formed by merging discrete sister holes to a primary hole. Simulations are performed at four blowing ratios of 0.25, 0.5, 1, and 1.5. The novel-shaped holes resulted in a significant reduction in the jet liftoff effect in comparison with a cylindrical and a forward-diffused shaped hole. Moreover, film cooling effectiveness is notably increased at the high blowing ratios of 1 and 1.5.  相似文献   
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