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1.
The purpose of this study was to determine if ultrasonographic measurement of multiple cross-sectional areas combined with linear dimensions of the bladder could be used as a method of estimating bladder volume in the dog, and, if so, to compare the accuracy of this estimation with that described previously using linear measurements alone. Fifty-two live dogs undergoing investigation for urological disease and 37 fresh canine cadavers were used for bladder volume determination. Maximal length, depth, width, and area were measured from the maximal longitudinal and transverse sonograms in each living animal. In cadavers, the cross-sectional area of the longitudinal section of the bladder was measured at one centimeter intervals, and the measurements were summed. Based on sequential partial regression analysis, the cross-sectional area of the longitudinal section of the bladder and length were the best predictors of actual bladder volume in living animals. However, based on the cadaver experiment, the best predictor of actual bladder volume was summed parasagittal area alone, and, in cadavers, this was a much better predictor of actual bladder volume than the combination of the cross-sectional area of the longitudinal section of the bladder and length. The formula derived in living dogs using the cross-sectional area of the longitudinal section of the bladder and length gave a less accurate estimation of bladder volume than a previously published formula where only linear measurements were used.  相似文献   
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Aurel J. Acher   《Water research》1982,16(4):405-410
A study of the sunlight irradiation effects, during the winter, on two herbicides present in sensitized, frozen, aqueous solutions is reported. These solutions of bromacil (3-sec-butyl-5-bromo-6-methyluracil) and of terbacil (3-t-butyl-5-chloro-6-methyluracil) were exposed directly to sunlight or covered by different layers of ice. Both herbicides were rapidly decomposed by sunlight in the presence of sensitizers like methylene blue (1.0 ppm), rose bengal (2.0 ppm), and riboflavin (4.0 ppm), at different pH (6.8, 8.2 and 9.1) of the solutions.The best results were obtained in the alkaline range of pH. At least 70 or 75% (at pH 9.1) and 25 or 60% (at pH 8.2) of the initial amounts of bromacil or terbacil, respectively, were decomposed in the first 2 h of irradiation, using the above sensitizers. At pH 6.8, a practical rate of photodecomposition reaction was observed only in the terbacil experiments.When the frozen samples were covered by ice blocks, up to 11 cm thick, the amount of incident light reaching them was usually attenuated, but the photodecomposition reaction rates remained high enough to be of practical value.The extract residues of the irradiated solutions (6 h, pH 8.2) of bromacil (1.0 ppm MB) and terbacil (2.0 ppm RF), analyzed by TLC and by GC-MS, were found herbicide free. Only minute amounts of one and four decomposition products were present in the concentrated solutions of these residues of bromacil and terbacil, respectively.  相似文献   
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The numerical simulation of the distillation and absorption/desorption process is made possible by coupling a transient two‐phase simulation in a structured packing with a model for the simulation of the species transfer. The two‐phase flow is modeled by the volume of fluid (VoF) method. The simulation of the locally resolved species transfer is conducted using the generalised continuous species transfer (GCST) model. The simulation data are evaluated for the separation efficiency of the tested packing by calculating the HETP value.  相似文献   
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Feature Models (FMs) are a popular formalism for modeling and reasoning about the configurations of a software product line. As the manual construction of an FM is time-consuming and error-prone, management operations have been developed for reverse engineering, merging, slicing, or refactoring FMs from a set of configurations/dependencies. Yet the synthesis of meaningless ontological relations in the FM – as defined by its feature hierarchy and feature groups – may arise and cause severe difficulties when reading, maintaining or exploiting it. Numerous synthesis techniques and tools have been proposed, but only a few consider both configuration and ontological semantics of an FM. There are also few empirical studies investigating ontological aspects when synthesizing FMs. In this article, we define a generic, ontologic-aware synthesis procedure that computes the likely siblings or parent candidates for a given feature. We develop six heuristics for clustering and weighting the logical, syntactical and semantical relationships between feature names. We then perform an empirical evaluation on hundreds of FMs, coming from the SPLOT repository and Wikipedia. We provide evidence that a fully automated synthesis (i.e., without any user intervention) is likely to produce FMs far from the ground truths. As the role of the user is crucial, we empirically analyze the strengths and weaknesses of heuristics for computing ranking lists and different kinds of clusters. We show that a hybrid approach mixing logical and ontological techniques outperforms state-of-the-art solutions. We believe our approach, environment, and empirical results support researchers and practitioners working on reverse engineering and management of FMs.  相似文献   
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X-ray structural and scanning electron microscope analyses show that the difference in the growth of the grains obtained by chemical molecular beam deposition (CMBD) depends on the sample composition. The Cd-enriched samples were of poor quality, while the samples grown at close stoichiometries were polycrystalline, had large grain size, and were uniform in their thickness.  相似文献   
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We examined the different personality dimensions between depression and anxiety with Cloninger's seven-factor model of temperament and character. The Temperament and Character Inventory (TCI), which measures four temperament and three character dimensions of Cloninger's personality theory (125-item short version), the Self-rating Depression Scale (SDS), and the State-Trait Anxiety Inventory (STAI) were administered to 223 Japanese students. With hierarchical regression analysis, the SDS score was predicted by scores of Harm-Avoidance, Self-Directedness, and Self-Transcendence, even after controlling for the STAI score. The STAI score was predicted by scores of Self-Directedness and Cooperativeness, even after controlling for the SDS score. More importance should be attached to these dimensions of character because they might contribute to both depression and anxiety.  相似文献   
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PURPOSE: Advances in cerebral vascular imaging suggest that patients with critical levels of carotid artery stenosis (> 70%) who have symptoms can be identified accurately and necessary information about the intracranial and extracranial circulation obtained before surgery without conventional angiography. We have used carotid duplex imaging in combination with magnetic resonance angiography (MRA) to evaluate 20 patients with symptomatic ipsilateral high-grade carotid stenosis. METHODS: All patients underwent CT and magnetic resonance imaging brain scans, as well as MRA and conventional arteriography of the cerebral circulation. Magnetic resonance angiograms were obtained with two-dimensional phase contrast and time-of-flight techniques. Phase contrast was used for intracranial vascular imaging and for determining qualitative flow velocities and the direction of blood flow in the circle of Willis. Two-dimensional time of flight was used to assess the carotid bifurcations. RESULTS: Twenty patients with symptoms (six with strokes, 11 with transient ischemic attacks, and three with amaurosis fugax) had duplex evidence of high-grade carotid stenoses. Computed tomographic and magnetic resonance brain scans were positive for cerebral infarction in six patients with clinical strokes. Comparison of MRA with conventional angiography was 91% accurate for high-grade stenoses and occlusions (sensitivity 100% and specificity 90% for stenosis; sensitivity/specificity was 100% for complete occlusion). Comparison of duplex imaging with conventional angiography demonstrated 86% accuracy for detection of severe stenosis or occlusion (sensitivity 94% and specificity 89% for stenosis; sensitivity and specificity were 100% for complete occlusion). CONCLUSIONS: This study suggests that combined use of MRA and duplex imaging is accurate for detection and evaluation of high-grade carotid stenoses in patients with symptoms.  相似文献   
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