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If an IT system is so so hopelessly and fundamentally flawed that there's no practical way to address its deficiencies one by one, a clean slate initiative might be the only way out of the swamp. The key is to make sure the drivers are sound, the process is retrospective, the solution is robust, and expectations are realistic. 相似文献
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Argues that most theorists in the realm of psychotherapy have not behaved like detached, impartial scientists but like itinerant proselytizers. In more recent times, a bias of a different kind has entered the field. "Hermeneutics," "social constructionism," and "postpositivism," although by no means synonymous, all offer a worldview that differs from established tenets of scientific data collection and objective measurement. These complex intellectual traditions emphasize that recordings of reality are mere projections and creations of the observer. The double impact of subjectivity and bias renders little hope for an optimistic future. A possible solution lies in the expansion of a broad-based social and cognitive learning theory that incorporates testable notions and empirically based clinical observations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Es werden die experimentellen und numerischen Ergebnisse dargelegt, um die gesamte Spannungs-Dehnungs-Kurve des Zugversuches mit sechs Kennwerten zu beschreiben. Dies sind: Elastizitätsmodul, Streckgrenze, Fließdehnung, Zugfestigkeit, Gleichmaßdehnung und Verfestigungsmodul. Dadurch werden auch im überelastischen Bereich numerische Beziehungen möglich zwischen: Verformungen und Spannungen, Dehngrenzen, Tangenten-Modulen und Arbeitsvermögen. Die Beziehungen erweitern die Ermittlung von Last- und Eigenspannungen, und die Berechnungen beim plastischen Umformen, beim Traglastverfahren und beim Messen von Kerbspannungen. 相似文献
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Bachant Janet L.; Lynch Arthur A.; Richards Arnold D. 《Canadian Metallurgical Quarterly》1996,13(1):153
The authors respond to the "relational" issue of Psychoanalytic Psychology (PP; Vol. 12, No. 1) and support Karol Marshall's remonstration about the need to clarify what exactly the category relational refers to. It is noteworthy that in this issue of PP the relational thinkers do not engage the specific topics of our essay. The author's article attempted to review the most comprehensive relational thinkers of that time across theoretical variables. Relationalists have begun to spell out the technical consequences of their perspective in recent discussions of neutrality, authority, and self-disclosure, among other issues. This is a useful trend in the relational literature, and we hope it continues. We are concerned, however, that the relational thinkers writing in this issue tend to dismiss the contributions to PP 12(1) because the perspectives presented there did not satisfy the relationalist vision of how scientific exchange should be undertaken. Although we feel that it is important for emerging points of view to be able to elaborate assumptions, constructs, and principles within their own framework and in their own way, constructive dialogue, much less a comparative analysis of the contributions and limitations of different points of view, requires that we have some common ground. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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OBJECTIVE: To examine the utility of single breath CO2 analysis as a noninvasive measure of cardiac output. SETTING: An animal laboratory in a university-affiliated medical center. DESIGN: A prospective, animal cohort study comparing 21 parameters derived from single breath CO2 analysis with cardiac output determined by an ultrasonic flow probe. SUBJECTS: Six healthy adult sheep. METHODS: The single breath CO2 analysis station consists of a mainstream capnometer, a variable orifice pneumotachometer, a signal processor, and computer software with capability for both on- and off-line data analysis. Twenty-one derived components of the CO2 expirogram were evaluated as predictors of cardiac output. Cardiac output was manipulated by successive injections of a hydraulic constrictor placed around the inferior vena cava. MEASUREMENTS AND MAIN RESULTS: Thirty-four measurements of cardiac output were available for comparison with derived variables from the CO2 expirogram. Stepwise linear regression identified two variables that were most predictive of cardiac output: a) the angle between the slope lines for phase II and III of the CO2 expirogram divided by the volume of CO2 per breath (angle/mL CO2); and b) the slope of phase II. The multivariate equation was highly statistically significant and explained 94% of the variance (adjusted r2 = .94, p < .0001). The bias and precision of the calculated cardiac output were .00 and .23, respectively. The mean percent difference for the cardiac output estimate derived from the single breath CO2 analysis station was 0.36%. CONCLUSIONS: Our data indicate that analysis of the CO2 expirogram can yield accurate information about the cardiovascular system. Specifically, two variables derived from a plot of expired CO2 concentration vs. expired volume predict changes in cardiac output in healthy adult sheep with an adjusted coefficient of determination of .94. Prospective application of this technology in the setting of lung injury and rapidly changing physiology will be essential in determining the clinical usefulness of the technique. 相似文献
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Skeleton weed, centaurea juncea, is a declared weed in Western Australia because it competes with grain crops for nutrients and moisture. When it is found during harvesting, mechanised teams search and eradicate it. In an earlier report of field trials (Hartley et al, 1989) it was reported that search teams' detection rate was poor and since search teams had usually never seen skeleton weeds, visual discrimination learning was to be expected and observed during searches. The present study investigated the nature of this discrimination learning in a laboratory by developing a training programme of colour photographic slides of weeds in stubble. Subjects receiving specific training with feedback on their performance compared with those receiving pseudo-training showed a significant improvement in detections. Subsequently the benefit of the programme was validated in a field trial. 相似文献
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The synthesis of a series of dyes derived from reaction of 2-methyl-4-(N-ethyl-N-hydroxyethyl)amino, lidicyano-styrene with acid chlorides, chloroformates, isocyanates and isothiocyanates is described. Data relevant to dye characterization by electron-impact induced fragmentation is reported. Dyeing and fastness properties of the dyes on cellulose secondary acetate, cellulose triacetate, nylon 6.6 and polyester fibres are discussed in terms of dye structure. Comparison is made between some related dyes derived from 2-methyl-4-(N-ethyl-N-β-aminoethyljamino-β,βdicyanostyrene. 相似文献