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GARY T. ANDERSON JU ZHENG RICHARD WYETH ALAN JOHNSON JOE BISSETT THE POSCH GROUP 《国际通用系统杂志》2013,42(6):879-896
Abstract A method of performing prognostic modeling of disease states is proposed. The technique uses rough sets to extract rules from a database. The data is then reformatted into a fuzzy logic template, and a learning algorithm is used to adjust the fuzzy set membership functions. The method is applied to the POSCH problem, which looks at risk factors associated with the progression of coronary artery disease. The POSCH data has several shortcomings, including a limited number of cases, correlated inputs, as well as noise on both the inputs and outcome. The problem was to predict progression of atherosclerosis in the LAD three years after baseline based on physiologic data available at baseline. The proposed rough/fuzzy set method correctly predicted progression of atherosclerotic disease in 69% of the patients, which is statistically better than neural network, rough set and logistic models performed. 相似文献
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A reflectance colorimeter with 32°C incubation/detection temperature successfully quantitated total and psychrotrophic microflora in raw milk. Correlations between reflectance colorimetry and the Standard Plate Count improved with preliminary incubation time: .50 (no preliminary incubation), .74 (24 h at 7°C), to .84 (48 h at 7°C). Correlations between reflectance colorimetry and the Psychrotrophic Bacterial Count were better than those achieved with the Standard Plate Count and improved: .53 (no preliminary incubation). 80 (24 h at 7°C), to .91 (48 h at 7°C). The 48 h preliminary incubation method would cost less and data would be available in 48 to 72 h compared to the 98 to 240 h for psychrotrophic plating methods. A second sample set (no preliminary incubation) could be analyzed to identify high-count samples in less than 24 h. Color detection times following sample refrigeration for 24 h at 0, 4. and 7°C were significantly different from samples tested before refrigeration. Identical sample time/temperature storage conditions are suggested 相似文献
15.
GARY CHINGA PER OLAV JOHNSEN ROBERT DOUGHERTY† ELISABETH LUNDEN BERLI‡ & JOACHIM WALTER§ 《Journal of microscopy》2007,227(3):254-265
This study presents the development of an ImageJ plugin for surface characterization. Based on gradient analysis, parameters, such as the gradient magnitude, orientation, mean resultant vector and surface area are derived. A comparative study of supercalendered (SC) papers was performed to verify the surface representations yielded by a laser profilometer. The surface representations of samples covered with carbon and gold were compared to untreated samples. The results confirm the suitability of gold coating for reducing the artefacts encountered on laser profilometry surface representations of paper. In addition, a complete scanning electron microscopy analysis is performed on the assessed samples to quantify the surface fraction covered by mineral fillers and to reveal the true 3D microstructure of SC surfaces. The influence of filler coverage and filler type on the gloss level of commercial SC papers is evaluated. The relationship between the surface topography, gloss and PPS roughness for a series of commercial SC papers is established. 相似文献
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GARY C. VEZZOLI 《Journal of the American Ceramic Society》1972,55(2):65-67
The electrical resistance of liquid sulfur was measured from just below the polymerization temperature to the vaporization point. Turning points in the resistance vs temperature curve, resulting presumably from polymerization and depolymerization, and a sharp decrease in resistance at 212°C agree well with previous results. Between ∼230° and 420°C, the resistance decreased without discontinuity. The resistance of selenium increased sharply by 3 orders of magnitude on melting and then decreased steadily by 5 orders of magnitude until the experiment was ended at 700°C. In both liquids, the electrical resistance as a function of temperature decreased more rapidly than that of an ideal intrinsic semiconductor whose molecular structure is stable over the temperature interval investigated. This rapid decrease is believed to result from chain dissociation and ring scission. 相似文献
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Sodium phosphate and a series of compounds containing Na, Zr, Si, P, and O were found to react with sodium at 380°C. The reaction products formed phosphine on hydrolysis. On the basis of these reactions and some thermodynamic calculations, it is not likely that any materials containing P-O bonds will be stable to sodium at the temperatures required for the Na-S battery or Na heat engine operation. 相似文献
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VLADIMIR D. KRSTIC PATRICK S. NICHOLSON GARY R. PURDY 《Journal of the American Ceramic Society》1981,64(8):451-455
Precipitation was studied for LiF single crystals containing up to 4 wt% MgF2 . Replica electron microscopy observations, combined with hardness and lattice parameter measurements, showed that, irrespective of the level of MgF2 , precipitation consistently occurs during quenching. Rapidly cooled crystals with lower MgF2 concentrations (<1 wt%) develop large cruciform particles of a metastable phase with approximate composition MgF2 -6LiF. Lower cooling rates or higher MgF2 contents caused transformation of these metastable particles to rod-shaped stable MgF2 phase. This occurs via nucleation on the metastable crosses. The large misfit between the LiF matrix and the MgF2 phase causes development of an incoherent interface and an associated disturbance of a propagating crack was observed near each MgF2 particle. 相似文献
19.
BOVINE MUSCLE TENDERNESS AS RELATED TO PROTEIN SOLUBILITY 总被引:1,自引:0,他引:1
ABSTRACT— The longissimus (modest degree of marbling) from forty beef ribs selected 48–56 hr post-mortem was used in two trials. Trial I involved A, C and E maturity ribs (10 each classification). Each rib was subjectively scored for texture (fresh) and adjacent longissimus samples were removed for the determination of protein solubility (fresh) and tenderness. Tenderness (cooked muscle) was measured with a Warner-Bratzler shear and taste panel. Protein solubilities were determined using 0.154M Krebs-Ringer-Bicarbonate buffer, 0.2M KCl + 0.01M K phosphate buffer, 1.1M Kl + 0.1M K phosphate buffer, and 0.03M K phosphate buffer. Trial II involved 10 A maturity ribs. The 0.2M KCl, 1.1M Kl and 0.03M K phosphate buffers as described for trial I were used for protein extraction. Additionally, sarcomere length was measured in formalin. Multiple regression equations were developed to predict tenderness in trial II. Protein solubilities were not significantly different between the carcass maturity groups although there were trends toward increased solubility as maturity increased. Tenderness tended to decrease from A to E maturity indicating a negative relationship between protein solubility and tenderness. Several significant negative correlations between protein solubility and tenderness were found in trial I (A maturity group) and trial II. Additionally, several significant negative correlations between texture and solubility were calculated. Correlations within the C and E maturity groups were variable and showed no definite trends. Multiple regression analyses showed that a combination of protein solubilities, texture score and sarcomere length accounted for 88% of the variation in shear force and 72% of the variation in taste panel tenderness. 相似文献
20.
REEXAMINED DISPLACEMENT AS FORMULATED BY E. J. MURRAY AND M. M. BERKUN (SEE 30:3). SIMILARITY TO THE GOAL AND SPATIAL PLACEMENT OF THE ALLEYS WERE MANIPULATED WITH AN ADDITIONAL VARIABLE OF BRIGHTNESS (BLACK) AND TEXTURE (HARDWARE CLOTH FLOOR) PREFERENCE IN 24 SPRAGUE-DAWLEY RATS. SS TRAVELED LEAST DOWN THE WHITE SMOOTH-FLOOR ALLEYS, MIDWAY DOWN THE GREY SCREEN-FLOOR ALLEYS, AND FARTHEST DOWN THE BLACK HARDWARE CLOTH-FLOOR ALLEYS. THIS OCCURRED REGARDLESS OF THE SPATIAL ARRANGEMENT OF THE ALLEYS OR THE COLOR OF THE ALLEY IN WHICH SS RECEIVED THE INITIAL APPROACH-AVOIDANCE TRAINING. SS TRAINED IN THE NONPREFERRED (WHITE) ALLEYS TOOK A GREATER NUMBER OF TRIALS TO RECOVER FROM APPROACH-AVOIDANCE CONFLICT THAN SS TRAINED IN THE PREFERRED (BLACK) ALLEYS. THE IMPORTANCE OF A PREFERENCE VARIABLE IN STUDIES OF CONFLICT BEHAVIOR IS STRESSED. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献