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141.
Richard J. Murray 《Information Systems Management》1991,8(3):7-15
In today's competitive world, many organizations are pursuing total quality improvement programs, and as a result of these initiatives, are seeking to define world class capabilities. The organizations with these aspirations are trying to improve product and service quality, business process quality, or delivered quality, and are becoming aware that information technology is playing a more substantial role in realizing these quality goals. 相似文献
142.
Overcoming contextual limitations on problem-solving transfer. 总被引:1,自引:0,他引:1
Five experiments investigated transfer from multiple analogs to a superficially dissimilar target problem. When subjects explicitly compared the analogs and then immediately attempted to solve the target problem in the context of a single experiment, transfer was obtained with significant frequency even without a hint that the analogs and target were related. Prehint transfer was sharply reduced or eliminated when the source analogs and the target were presented in different contexts, even when the transfer test was immediate. However, prehint transfer was enhanced, even after a context shift and a week-long delay between reading the source analogs and solving the problem, when the following conditions were met: The target problem was reworded slightly to emphasize a structural feature that it shared with the analogs; three rather than two source analogs were provided; and detailed, schema-oriented questions were used to help subjects focus on the problem-relevant aspects of the stories. Although spontaneous transfer between small numbers of dissimilar analogs is difficult to obtain, it can be achieved by manipulations that foster abstraction of a problem schema from the training examples. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
143.
144.
Robert Comrie Stanley Affrossman David Hayward Richard A. Pethrick 《The Journal of Adhesion》2002,78(11):967-985
Broadband dielectric measurements (10 -2 to 3 GHz) are reported on the effects of exposure of thick film adhesive-bonded structures to moisture. Measurement of the dielectric properties over a broad frequency range allows identification of water both in voids and as a molecular dispersion in the matrix. Changes in the low frequency region of the dielectric spectrum can be attributed to a combination of processes associated with plasticisation of the adhesive, interfacial polarisation effects, and hydration of the surface oxide layer. The data obtained are complemented by mechanical testing and failure analysis of the bond structure measured as a function of the time of exposure. This study indicates that for thick film adhesives the ageing characteristics are apparently independent of the surface treatment. In one of the joints studied an additional feature is identified which appears to correlate with the premature aging of the joint structure. 相似文献
145.
Carl A. Soderstrom Patricia C. Dischinger Gordon S. Smith J.Richard Hebel David R. McDuff David A. Gorelick Timothy J. Kerns Shiu M. Ho Kathleen M. Read 《Accident; analysis and prevention》1997,29(6):715-721
A structured in-depth interview employing standardized criteria was used to determine the prevalence of lifetime and current alcohol dependence (alcoholism) in unselected consecutive patients admitted to a regional Level I trauma center. Of 629 patients, 157 (25.0%) were current alcoholics at the time of injury. An additional 87 (13.8%) were diagnosed as lifetime non-current alcoholics. There was no significant difference in the rates of current alcohol dependence among patients injured in vehicular crashes (23.5%), other unintentional trauma victims (29.3%), and those injured as a result of violence (24.6%). Of BAC + (blood alcohol concentration positive) patients, 54.5% were current alcoholics. However, 14.4% of alcohol-negative patients were also diagnosed as alcohol dependent. 相似文献
146.
Recovery of residual oil using the alkali/surfactant/polymer process: effect of alkali concentration
An experimental study was conducted to examine the effectiveness of sodium carbonate in alkali, surfactant and polymer combined slugs in recovering waterflood residual oil. The effects of sodium carbonate concentration on the slug viscosity, interfacial tension, and phase behavior were first examined. Core flood experiments were conducted with unfired linear Berea sandstone cores. The incremental oil recovery, oil cut, residual resistance factor, and chemical propagation were measured for each flood.A significant oil bank was formed for all combined slugs having sodium carbonate concentration ≥1 wt%. The incremental oil recovery, oil cut and the injectivity of the combined slugs greatly improved as sodium carbonate concentration was increased. The effect of sodium carbonate concentration on chemical propagation was dramatic for the synthetic surfactant; a slight delay in surfactant breakthrough and a much slower rate of surfactant propagation were observed at high sodium carbonate concentrations.The results obtained in the present study indicate that the residual oil was recovered by two mechanisms: low interfacial tension and wettability reversal. The former mechanism is dominant at sodium carbonate concentrations ≤1 wt%, whereas the latter plays an important role only at high sodium carbonate concentrations. 相似文献
147.
Ion V. Nicolaescu Gabriel Tardos Richard E. Riman 《Journal of the American Ceramic Society》1994,77(9):2265-2272
A thermogravimetric method for the measurement of carbon, nitrogen, and oxygen in aluminum nitride is described. Since carbon oxidation occurs at lower temperatures than the oxidation of the aluminum compounds, thermogravimetric analyses in the respective temperature regimes can yield measurement of the oxygen, nitrogen, and carbon content. Thermogravimetric analyses were performed on mixtures of aluminum nitride and carbon with various concentrations in order to evaluate the accuracy of this method. The results were compared with those obtained by the hot gas extraction method. Errors produced by overlapping of the temperature ranges of the reactions were evaluated and experimental conditions were optimized to minimize error. This method can produce reliable results at elemental concentrations higher than a few percent. The absolute errors of the C/AI, N/Al, and O/Al atomic ratios were less then 0.02. The detection limit was evaluated to 0.2 wt% of each element. The applicability of the method to the study of the kinetics of the nitridation reaction was demonstrated. 相似文献
148.
Afam I Jideani Richard K Owusu Apenten H G Muller 《Journal of the science of food and agriculture》1994,65(4):465-476
The effect of cooking on proteins from acha and durum wheat was assessed from an analysis of protein extractability, gel electrophoretic profiles, in-vitro protein digestibility (IVPD) and the amino acid compositions of wholemeal flour and residue proteins. Heating wholemeal flour samples at 100–140°C (t = 10–40 min) resulted in 0–30% and 45–55% decreases in acha and durum protein solubility, respectively. In general, high molecular weight (30–70 k Da) protein subunits were more susceptible to heat damage. For both cereals, sodium dodecyl sulphate (SDS; 10 g litre?1) and/or dithiothrcitol (DTT; 10 mM ) increased protein solubility in unheated and heated samples. The IVPD index was 90–91% and was not significantly altered by cooking (100–120°C, t = 40 min). Cooking at extreme temperatures (140°C, t = 40 min) reduced the IVPD by 8% (P = 0.05). Osborne fractionation resulted in a durum or acha residue level of 7.8% or 55.2%. Treatment with solvent containing propanol, SDS and/or DTT at room temperature followed by SDS-polyacrylamide gel electrophoresis of non-solubilised proteins showed that the glutelin fraction of acha, with the exception of a 65 kDa subunit, was insoluble owing to strong inter-subunit hydrophobic and disulphide interactions. Wholemeal acha flour and residue protein showed a significantly greater level of hydrophobic and sulphur amino acids as well as glutamine which is associated with H-bonding. The possibility that cereal protein solubility is also dependent on protein-carbohydrate links is discussed. 相似文献
149.
Although all-optical networks were being thought about almost ten years ago, until recently it would have been premature to talk about such networks as being truly usable. Now, ways of removing most of the roadblocks to practicality have come clearly into view. It is generally agreed that time-division packet switching in the form of asynchronous transfer mode (ATM) is likely to constitute the next generation of networking, both local and wide area; but what about the generation after that? While people are evolving SONET/ATM, the present Internet, and such emerging ambitions as the National Information Infrastructure (NII), in order to serve the needs anticipated for the next decade, optical fiber is being steadily installed at a rate of 700 miles per day in the United States alone. Furthermore, this resource is being extended steadily outward from the telco or cable provider backbone into customer premises, so that within the lifetime of the ATM generation, we may expect extremely rich fiber connectivity of a large number of homes and offices 相似文献
150.
Sodowsky Gargi Roysircar; Taffe Richard C.; Gutkin Terry B.; Wise Steven L. 《Canadian Metallurgical Quarterly》1994,41(2):137
Presents the Multicultural Counseling Inventory (MCI), a self-report instrument that measures multicultural counseling competencies. Study 1 comprised 604 psychology students, psychologists, and counselors in a midwestern state. In Study 2, respondents were a national random sample of 320 university counselors. Instrument analysis included exploratory principal-axis factor analysis with oblique rotation, assessment of factor congruence between the factor structures of the 2 samples, LISREL confirmatory factor analysis to test the relative goodness of fit of 6 competing factor models of the MCI, and tests of internal consistency reliabilities. Results indicate that the MCI has 4 factors: Multicultural Counseling Skills, Multicultural Awareness, Multicultural Counseling Relationship, and Multicultural Counseling Knowledge. A higher order, more general multicultural counseling factor is also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献