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E. E. Sampson (see PA, Vols 62:8675 and 63:8604) has argued for the adoption of a new attitude toward science (Paradigm II) that dispenses with the traditional ideal of value-free observation and analysis (Paradigm I). It is argued that the epistemological underpinnings of Paradigm I science do not support the preferential treatment accorded to value-free observation, but rather lead to a radical relativism wherein value-free observations are indistinguishable from value-laden ones. The internal analysis of Paradigm I thus arrives at the same critical conclusion as Sampson. (6 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Comments on K. J. Gergen's (see record 1986-00014-001) rejection of the empiricist claim that observation can or should determine whether statements about the world are accepted by science and his postulation that science is a social activity that can be analyzed in terms of social concepts. The present author delineates several theoretical options that are available to anti-empiricists and sociologs and discusses difficulties associated with less plausible options. (4 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The article presents results of the investigation of the quantitative evaluation of the degree of damage, described by the measure of accumulated plastic strain obtained in a static tensile test, using selected non-destructive techniques. Inconel 718 alloy was tested. The tests were conducted using a new type of specimens of variable cross-sectional area of measuring part. This provided a continuous distribution of plastic strain in the gage part of the specimen. The permanent deformation that varies along the sample axis enables an analysis of damage induced by a plastic deformation. The proposed method enables replacing the series of specimens by one sample. Degradation of the alloy corresponds with the changes of the electromagnetic properties of the material—the phase angle of the complex impedance of the eddy current, as well as with acoustics properties of material—acoustic birefringence of ultrasonic waves. It allows to determine the degree of damage of the material using noninvasive, non-destructive methods. Using the damage parameter proposed by Johnson it is possible to obtain the correlation between the non-destructive results and a damage degree of the material. The presented testing method delivers information about changes in the material structure caused by permanent deformation.

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In this work, a model is presented, which is the basis of a quality control concept for the injection molding process. Contrary to statistical methods, this model uses physical dependencies of two quality parameters on four influencing parameters. The influences of holding pressure, holding time, melt temperature, and mold temperature on part mass and dimensions are described based on the fundamental material behavior such as pvT‐data or energy equation. Furthermore, the influence of viscosity changes is indirectly taken into account using the injection work. Assuming only small deviations of the influencing parameters around an optimized operating point, the four parameters are treated as being independent from each other. With this assumption, a product ansatz was chosen with different functions for each influencing factor. Applying basic algebra, the starting equation was transformed into a form that describes either the change in part mass or characteristic part dimensions as a function of the influencing factors. The final equation for the part mass contains six model parameters, whereas nine model parameters are necessary for the equation for the part length. To obtain those model parameters some systematic experiments are required. Once the parameters are known, the model is able to calculate the change of the target values when the influencing factors vary around the operating point. The model was tested experimentally with focus on dimensions using a plastic cover made of an acrylonitrile butadiene styrene (ABS) grade. For the investigated part geometry and material grade, the process behavior was described well by the model. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
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Purpose: The purpose of this study was to determine the relationship between the working alliance and employment outcomes in persons with severe mental illness receiving vocational services. Another purpose of this study was to determine whether working alliance differences exist between clients receiving evidence-based supported employment services and those receiving traditional stepwise vocational services. Design: This study was a secondary analysis of a 2-year randomized controlled trial comparing two employment programs providing services to people with severe mental illness. Results: Contrary to expectations, no overall relationship was found between the working alliance and employment outcomes. As predicted, supported employment participants each assigned to a single vocational worker had more positive working alliances than participants served by a team of vocational workers in the traditional vocational program. Conclusions/Implications: The lack of an association between the working alliance and employment outcomes is inconsistent with previous literature. Further research is needed using standardized working alliance measures and larger samples that include both working and nonworking clients. Evidence-based supported employment, which employs individual caseloads, seems to foster better relationships than a team-based vocational approach, although future research is needed to replicate this finding. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Comments on an article by A. W. Staats (see record 1992-03794-001) recommending a unified positivism to save psychology's threatened scientific status. However, while a unified psychology might be desirable, the disparate bodies of empirical data may not lend themselves to a unified positivism that assumes underlying principles connecting all the data. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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RATIONALE AND OBJECTIVES: The authors evaluate the role of low-field strength magnetic resonance imaging (MRI) compared with sonography in the evaluation of degenerative changes of tendons, with histologic correlation, based on investigations of horse cadavers. METHODS: Low-field MRI and sonography was performed in 42 hours specimens for the evaluation of tendons and ligaments. Magnetic resonance imaging included sagittal and axial T1-weighted, T2-weighted, and gradient echo images. Sonography and MR images were evaluated for degenerative changes or tears and the findings were correlated with the histologic results. RESULTS: Using histologic findings as a gold standard, the accuracy for the sonographic evaluation was 65.9%, sensitivity was 16.7%, and specificity was 100%. The corresponding data for low-field MR imaging were 70.5% accuracy, 44.4% sensitivity, and 88.5% specificity. CONCLUSIONS: Low-field MRI investigation allows more accurate staging of tendinous changes than sonography. It is more reproducible and potentially includes the advantages of the combined evaluation of bones, ligaments, and soft tissue.  相似文献   
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