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61.
Image processing on encoded video sequences 总被引:2,自引:0,他引:2
This paper presents a novel approach to processing encoded video sequences prior to complete decoding. Scene changes are easily detected using DCT coefficients in JPEG and MPEG encoded video sequences. In addition, by analyzing the DCT coefficients, regions of interest may be isolated prior to decompression, increasing the efficiency of any subsequent image processing steps, such as edge detection. The results are currently used in a video browser and are part of an ongoing research project in creating large video databases. The procedure is detailed with several examples presented and studied in depth. 相似文献
62.
The increase in the off-state current for sub-quarter micron CMOS technologies is making conventional IDDQ testing ineffective. Since natural process variation together with low-VTH devices can significantly increase the absolute leakage value and the variation, choosing a single threshold for IDDQ testing is impractical. One of the potential solutions is the cooling of the chip during current testing. In this paper we analyze the impact of CMOS technology scaling on the thermal behavior of different leakage current mechanisms in n-MOSFETs and estimate the effectiveness of low temperature IDDQ testing. We found that the conventional single threshold low temperature IDDQ testing is not effective for sub-quarter micron CMOS technologies and propose the low temperature ΔIDDQ test method. The difference between pass and fail current limits was estimated more than 200× for 0.13-μm CMOS technology. 相似文献
63.
The effectiveness of single threshold I
DDQ measurement for defect detection is eroded owing to higher and more variable background leakage current in modern VLSIs. Delta I
DDQ is identified as one alternative for deep submicron current measurements. Often delta I
DDQ is coupled with voltage and thermal stress in order to accelerate the failure mechanisms. A major concern is the I
DDQ limit setting under normal and stressed conditions. In this article, we investigate the impact of voltage and thermal stress on the background leakage. We calculate I
DDQ limits for normal and stressed operating conditions of 0.18 m n-MOSFETs using a device simulator. Intrinsic leakage current components of transistor are analyzed and the impact of technology scaling on effectiveness of stressed I
DDQ testing is also investigated. 相似文献
64.
Paolo Montangero Michele Liberatore Giuseppina Arman 《Quality and Reliability Engineering International》1991,7(4):261-265
OBIC and PL imaging modes of a SOM have been successfully applied to the failure analysis of catastrophically degraded DC-PBH lasers. High lateral resolution, variable in-depth penetration and selective excitation are the most interesting features. A degradation mechanism has been found due to the development of leakage paths in the confining junctions. 相似文献
65.
The dynamic behaviour of binary blends of linear polystyrene fractions in the terminal zone of the relaxation spectrum presents interesting peculiarities which have been discussed in a previous paper by Montfort. The viscoelastic properties are characterized by a representation in the complex plane of viscosities. In this paper, we propose an empirical blending law which represents such behaviour over a large range of frequencies. The conclusions of this law on the limiting values of η0 and J0e are compared with those deduced from the blending laws of Graessley and BMEO. 相似文献
66.
Arman Hasan Abdelghany Osman Saima Mahmoud Abu Aldahan Ala Mahmoud Bahaa Hussein Saber Fowler Abdel-Rahman 《Bulletin of Engineering Geology and the Environment》2021,80(6):4221-4233
Bulletin of Engineering Geology and the Environment - Petrological features of carbonate rocks that exert control on their mechanical and physical properties are examined in the study presented... 相似文献
67.
A series of La1−xSbxFeO3 was prepared using the conventional solid state method. XRD revealed the formation of the orthorhombic structure with space group Pbnm. The data showed that, the molar magnetic susceptibility and coercive field HC were increased from 9.16 × 10−3 to 26.9 × 10−3 emu g−1 mol and 1196 to 5465 Oe from for LaFeO3 to La0.95Sb0.05FeO3, respectively. The coercive field (HC) of the sample with x = 0.05 increased 6 times than that of the parent LaFeO3 and the saturation magnetization (Ms) was increased from 0.1614 emu g−1 for the parent LaFeO3 to 0.2654 emu g−1 for the doped sample. The dielectric constant (?′) was increased with increasing the Sb3+ content. The ac conductivity (σ) increases from 2.36 × 10−3 Ω−1 m−1 for the LaFeO3 to 30 × 10−3 Ω−1 m−1 for the sample La0.95Sb0.05FeO3 at T = 553 K and frequency 1 MHz. The sample La0.95Sb0.05FeO3 is concluded to be a novel single phase multiferroic material. 相似文献
68.
In this communication we describe a segmentation technique which combines two properties in an iterative and hierarchial matter to correctly segment and classify the given cell images. The technique is applied to digital images taken from microscope slides of cultured rat liver cells, and the goal is to classify these cells into one of three possible classes. The first class cells (I) are morphologically normal and stain the darkest. The second class cells (II) are slightly damaged showing both nuclear and cytoplasmic swelling with resultant lessening of staining affinity. The third class cells (III) are markedly damaged as demonstrated by the presence of cytoplasmic vacuolization, or are completely disintegrated. First class cells are classified by taking advantage of their staining affinity; the original gray level image is segmented into four gray levels. The darkest is then classified as type I. Type III cells are classified by using high business as a characteristic; the standard deviation of the original image is segmented into four business levels. The highest level is classified as type III cell. Assuming only the three cell types are present in any given image, the remaining non-background unclassified pixels are determined to belong to type II cells. 相似文献
69.
The drilling of a number of boreholes to determine the soil profile of a given area is time consuming and costly. This paper
describes estimated soil profiles obtained using a model based on artificial neural networks (ANN). ANN is a powerful data-modelling
tool capable of capturing and representing complex relationships between input and output. It deals with many multi-variate
problems for which an exact analytical model does not exist or is very difficult and time consuming to develop. The main settlement
in the Adapazari region was selected to demonstrate the capability of such model. The results obtained using ANN are promising
when compared with the soil profile obtained from boreholes.
相似文献
70.
Che Sidik Nor Azwadi Mohammadjavad Zeinali Arman Safdari Alieh Kazemi 《Numerical Heat Transfer, Part A: Applications》2013,63(12):906-920
Heat transfer behavior in a 2-D square lid-driven cavity has been studied for various pertinent Reynolds and Rayleigh numbers. The lattice Boltzmann method, a numerical tool based on the particle distribution function is applied to simulate a thermal fluid flow problem. Bhatnagar-Gross-Krook (BGK) is combined with the double population thermal Lattice Boltzmann model to solve mixed convection in a square cavity. An adaptive-network-based fuzzy inference system (ANFIS) method is trained and validated using BGK Lattice Boltzmann model results. The results show that the trained ANFIS model successfully predicts the temperature and flow fields in a few seconds with acceptable accuracy. 相似文献