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1.
Multimedia Tools and Applications - Facial expression is the most common technique is used to convey the expressions of human beings. Due to different ethnicity and age, faces differ from one...  相似文献   
2.
We recently identified three areas of Sp1 binding located between -568 and -453 of the 5' flanking region of the murine alpha2(I) collagen promoter which are necessary for optimal activity. We now identify two additional regions of Sp1 binding located at -371 to -351 (region 4) and at -690 to -613 (region 5), which when mutated increased promoter activity in transfected rat hepatic stellate cells indicating they contain negative regulatory elements. AP-2 bound to region 4 while YY1 bound most strongly to region 5. AP-2 decreased Sp1 binding to region 4 and had a dual effect on Sp1 binding to region 5 decreasing and increasing Sp1 binding at low and high concentrations of AP-2, respectively. YY1 enhanced Sp1 binding to both regions. AP-2 inhibited or enhanced the stimulatory effect of a transfected Sp1 expression vector on the alpha2(I) collagen promoter in Drosophila cells at low or high AP-2 expression, respectively. YY1 enhanced or inhibited the activation of the promoter by low or high Sp1 expression, respectively. This study identifies two negative regulatory elements in the murine alpha2(I) collagen promoter and shows that AP-2 and YY1 interact with Sp1 at these sites and can inhibit the activating action of Sp1.  相似文献   
3.
The detected contrast and dynamic ranges of Cd1-xZnxTe semiconductor detectors have been measured, within the X-ray diagnostic energy range, using a contrast sensitivity phantom. The aim of this study is to optimize the image quality parameters of these solid state ionization devices for flat panel digital radiographic applications. The experimental results of this study indicate that Cd1-xZnxTe detectors have excellent detected contrast response and large dynamic range  相似文献   
4.
Hydrogen bonding interaction within a small ensemble of water molecules, that within a group of water molecules and end-groups of Z-dol and Z-tetraol, and the effect of electrolyte ionic pair such as LiCl upon these interactions were examined by the molecular dynamics method based on the potential given by a semi-empirical SCF quantum mechanics. It was revealed that the strength of the hydrogen bond increased rapidly as the size of droplet increased, relating to the population density of hydroxyl units, and that such interaction was amplified significantly by the presence of electrolyte ionic pair. An extraordinary interaction was thus predicted between Z-tetraol and aqueous solution of alkali halide. An experimental study thence conducted revealed that Z-tetraol and aqueous NaCl solution (2 M) formed an extremely stable water-in-oil type emulsion. The emulsion consists of spheroids of several nanometers across wherein several thousands of water molecules are encased by several tens of Z-tetraol end-groups. The interfacial layer of each spheroid is formed and stabilized by the hydrogen bonding interaction between the hydroxyl units of the tetraol-ends and water molecules enhanced by the electrolyte ionic pairs. When disks coated with Z-tetraol were tested for flyability at high humidity, the head-disk interaction detected acoustically increased with time. Spontaneous formation of globules resulting from interaction of tetraol end-groups and water molecules assisted by ubiquitously present alkali halide contaminant would account for the observed increase of the head-disk interaction. Possible structures of perfluoropolyether lubricants ideal for magnetic disk application are discussed.  相似文献   
5.

Face expression recognition has been proved as a challenging task in image processing. Many related works on facial expression recognition had done but they faced several challenges during the classification of data with the stored database. It carried out various workflows on improvisation of classifiers based on deep learning but they have been lagging in understanding facial expression mainly because of disastrous forgetting, time management, data mixing, and data overfitting, etc. Ignoring all these challenges would lead to inaccurate recognition of facial expressions. Hence to overcome all the above issues this work proposed a model named adaptive increasing-margin adversarial neural iterative model involves triple threat filtration techniques along with modified scaling density-based spatial clustering of applications with noise and dual feature model for obtaining a better quality featured image. Advance back propagation artificial neural network model is initiated to overcome catastrophic forgetting, underfitting of data, over fitting of data, etc. Thus, the proposed work achieves better efficiency as well as high accuracy in terms of facial expression recognition.

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6.
Intensive ambient air sampling was conducted in Tampa, FL, during October and November of 2002. Fine particulate matter (PM(2.5)) was collected at 30 min resolution using the Semicontinuous Elements in Aerosol Sampler II (SEAS-II) and analyzed off-line for up to 45 trace elements by high-resolution ICPMS (HR-ICPMS). Divalent reactive gaseous mercury and particulate bound mercury were also measured semicontinuously (2 h). Application of the United States Environmental Protection Agency's (EPA) Unmix receptor model on the 30 min resolution trace metals data set identified eight possible sources: residual oil combustion, lead recycling, coal combustion, a Cd-rich source, biomass burning, marine aerosol, general industrial, and coarse dust contamination. The source contribution estimates from EPA Unmix were then run in a nonparametric wind regression (NWR) model, which convincingly identified plausible source origins. When the 30 min ambient concentrations of trace elements were time integrated (2 h) and combined with speciated mercury concentrations, the model identified only four sources, some of which appeared to be merged source profiles that were identified as separate sources by using the 30 min resolution data. This work demonstrates that source signatures that can be captured at 30 min resolution may be lost when sampling for longer durations.  相似文献   
7.
Kasai  Paul H.  Raman  Vedantham 《Tribology Letters》2002,12(2):117-122
It has been shown earlier that addition of X1P (partially fluorinated hexaphenoxy cyclotriphosphazene) to the lubricant Z-DOL markedly increases the durability of the magnetic disk system. Its efficacy has been attributed to the strong nucleophilic property of the triphosphazene ring. It follows that perfluoropolyethers terminated with nucleophilic end groups should exhibit a durability comparable to that of the Z-DOL/X1P mixture. To this end perfluoropolyethers with dialkylamine end groups were conceived and synthesized as better alternatives to Z-DOL or to the Z-DOL/X1P mixed system. Examination of the newly synthesized lubricant revealed that (1) perfluoropolyethers with dialkylamine end groups are resistant to the degradation process catalyzed by Lewis acid (e.g., aluminum oxide), (2) disks lubricated with these lubes have durability significantly better than those lubricated with Z-DOL, (3) in the drive system with disks lubricated with these lubes, the issue of the silicon oxide formation from siloxane contaminant is effectively contained (owing to the absence of degraded lube), and (4) the HDI system with disks lubricated with these lubes performs well even in the most aggressive atmospheric condition, i.e., nitrogen with 0% relative humidity.  相似文献   
8.
The timing characteristics of a planar Cd1-xZnx Te sample at each frequency of a scanning square-wave test pattern, has been measured. This study is aimed at evaluating the speed characteristics of a Cd1-xZnxTe detector for X-ray imaging and computed tomographic (CT) applications. The experimental results of this study indicate that the temporal response of a Cd1-xZnxTe detector based X-ray system, improves significantly by optimizing the X-ray tube and detector parameters  相似文献   
9.
In this paper, the detective quantum efficiency (DQE) of cadmium zinc telluride (CZT) detector samples for digital radiography has been measured. Specifically, this study is aimed at investigating the zero-frequency DQE(0) under different X-ray tube and detector parameters. The experimental results of this study indicate that the DQE(0) of the CZT samples is strongly dependent upon the irradiation geometry. This is attributed to the incomplete charge collection process, which can be further improved by controlling the purity of the samples and the contact type.  相似文献   
10.
Considerable evidence exists to support the hypothesis that the hippocampus and related medial temporal lobe structures are crucial for the encoding and storage of information in long-term memory. Few human imaging studies, however, have successfully shown signal intensity changes in these areas during encoding or retrieval. Using functional magnetic resonance imaging (fMRI), we studied normal human subjects while they performed a novel picture encoding task. High-speed echo-planar imaging techniques evaluated fMRI signal changes throughout the brain. During the encoding of novel pictures, statistically significant increases in fMRI signal were observed bilaterally in the posterior hippocampal formation and parahippocampal gyrus and in the lingual and fusiform gyri. To our knowledge, this experiment is the first fMRI study to show robust signal changes in the human hippocampal region. It also provides evidence that the encoding of novel, complex pictures depends upon an interaction between ventral cortical regions, specialized for object vision, and the hippocampal formation and parahippocampal gyrus, specialized for long-term memory.  相似文献   
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