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101.
An iterative array is proposed which can be used to carry out binary division based on the principle of successive subtraction. The function of each cell of the array is dependent on the result of subtraction in the array. 相似文献
102.
Compared J. L. Holland's occupational categories with groups of occupations that resulted from the application of L. L. McQuitty and J. A. Clark's iterative intercolumnar correlational analysis to the scales of the Strong Vocational Interest Blank, the Minnesota Vocational Interest Inventory, and the Kuder Occupational Interest Survey for men and women. Results indicate that clusters of occupations exist that are internally consistent, and these usually agreed with the groups of occupations in Holland's classification. The hierarchical structure of the clusters followed the hexagonal ordering of Holland's occupational categories suggested in other studies. In addition, the usefulness of all 3 letters in Holland's occupational classification was supported. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Smith D. Leasel; Pruitt Dean G.; Carnevale Peter J. 《Canadian Metallurgical Quarterly》1982,42(5):876
Augmented the research design used by H. H. Kelley et al (1967) to examine negotiation about the division of a common reward to include 2 factors expected to interact with bargainer's limit: time pressure and the other bargainer's toughness. Five hypotheses were tested: (1) Concession rate is lower the higher a bargainer's limit; (2) concession rate is greater under high, as opposed to low, time pressure; (3) bargainer toughness is mismatched, that is, the greater the other's initial demand and the slower the other's concessions, the larger will be the S's concessions; (4) concession rate is more influenced by limit level under high, as opposed to low, time pressure; and (5) mismatching of the other's toughness is more pronounced under high time pressure than under low. Ss were 48 female undergraduates. All hypotheses were supported except Hypothesis 3, which received partial support. Ss conceded slowly when the other conceded slowly and rapidly when the other conceded rapidly. A possible explanation for this finding is that matching occurs when it is possible to judge the fairness of the other's offers. When this is possible, bargainers engage in reciprocity. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
A miniature, implantable force transducer has been developed for the extraluminal measurement of segmental smooth muscle contractility and has been applied to the oviduct in the Macaca mulatta. The force transducer makes use of a commercially available piezoresistive silicon strain sensor bonded to a flexible metal strip. The device is housed in a tissue compatible, gas sterilizable tubule upon which are placed sutures for subsequent extraluminal attachment to an organ. 相似文献
105.
The characteristics of a new type of capacitance spectroscopy of deep traps in semiconductors are reviewed. A double radiation
source technique is employed, the first source controlling the occupation of the traps and the characteristic time constant
of the experiment, the second probing the spectral distribution of traps by selectively photoinducing emission to the conduction
and valence bands. Time differentiation enhances the detectivity of the traps and minimizes drift problems. Typical spectra
obtained with this quasi-equilibrium spectroscopic technique are described. The chromium trap in GaAs presents a distinctive
feature with interesting properties which are discussed. Comparisons with thermal capacitance measurements are made, showing
the complementary nature of the two methods. The use of the technique to detect out-diffusion of Cr from an insulating substrate
into an epitaxial layer is described. 相似文献
106.
A. Dean 《Microelectronics Reliability》1981,21(6):779-782
This paper discusses the development programme used for a VLSI bipolar process for the production of a 2000 Gate ULA. 相似文献
107.
Reconstruction and quantification of the carotid artery bifurcation from 3-D ultrasound images 总被引:4,自引:0,他引:4
Barratt DC Ariff BB Humphries KN Thom SA Hughes AD 《IEEE transactions on medical imaging》2004,23(5):567-583
Three-dimensional (3-D) ultrasound is a relatively new technique, which is well suited to imaging superficial blood vessels, and potentially provides a useful, noninvasive method for generating anatomically realistic 3-D models of the peripheral vasculature. Such models are essential for accurate simulation of blood flow using computational fluid dynamics (CFD), but may also be used to quantify atherosclerotic plaque more comprehensively than routine clinical methods. In this paper, we present a spline-based method for reconstructing the normal and diseased carotid artery bifurcation from images acquired using a freehand 3-D ultrasound system. The vessel wall (intima-media interface) and lumen surfaces are represented by a geometric model defined using smoothing splines. Using this coupled wall-lumen model, we demonstrate how plaque may be analyzed automatically to provide a comprehensive set of quantitative measures of size and shape, including established clinical measures, such as degree of (diameter) stenosis. The geometric accuracy of 3-D ultrasound reconstruction is assessed using pulsatile phantoms of the carotid bifurcation, and we conclude by demonstrating the in vivo application of the algorithms outlined to 3-D ultrasound scans from a series of patient carotid arteries. 相似文献
108.
A quantitative method was developed for the determination of heme (ferriprotoporphyrin IX) using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS). The method was designed for forensic characterization of the use of blood agar in preparation of Bacillus spores. An alkali wash of 0.3 M ammonium hydroxide was used to solubilize heme from spore samples. The wash was concentrated and analyzed by MALDI-TOFMS. Experimental parameters were optimized to obtain the best signal intensity, maximize signal reproducibility, and improve day-to-day repeatability of the measurement. Sinapinic acid was found to be the best matrix. A sandwich sample preparation protocol was determined to increase the shot-to-shot and point-to-point reproducibility of the measurement. Cobalt(III) protoporphyrin was used as an internal standard and the analyte/internal standard ratio responses from solutions of known concentrations were used to construct a calibration curve (R(2) = 0.993). Limits of detection and quantitation for heme were calculated to be approximately 0.4 (200 fmol) and 0.8 microM (400 fmol), respectively. Spore samples prepared on blood agar and nonblood agar were analyzed using the method. Heme was detected at a concentration of approximately 0.3 ng/mg of spore on samples prepared on blood agar and purified by extensive washing. Heme was not detected on spore samples prepared without blood. 相似文献
109.
A pore closure model of gas-solid reactions has been extended to include the effect of bulk flow and reversible reactions. Both effects are shown to be of major importance in the chlorination of magnesia. During the course of reaction the controlling resistance is shown to change from pore diffusion to product layer diffusion to pore diffusion caused by closure of the pore. 相似文献
110.