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1.
An empirical study is reported comparing biserial r and triserial r for 100 samples from each of three populations (product-moment r's of .28, .66, and .91). The empirical standard deviations of triserial r were consistently lower than the standard errors of biserial r. Furthermore, "… the simple formula can be safely used when the high and low groups do not differ by more than .10." (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

2.
"In connection with some work on the topic of the core curriculum, the Education and Training Board Committee on Doctoral Education received letters from thirteen 'elder statesmen' in reply to the following three questions: What is a psychologist? What are his methods? What facts should he know?" Excerpted statements from the letters of Allport, Boring, Carmichael, Dashiell, Elliott, Hilgard, Leeper, Merrill, Murphy, Robert Sears, Tolman, W. L. Wells, and Woodworth are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

3.
Forgiveness is proposed to be an important pathway through which the effects of religion on health are mediated. Three separate studies were conducted to examine this hypothesis. In Study 1, older adults (n = 605) completed measures of forgiveness, religiosity, and health. Feeling forgiven by God fully mediated associations between frequency of attendance, frequency of prayer, and belief in a watchful God with successful aging. Self-forgiveness and forgiveness of others partially mediated the religion–health relationships. In Study 2, 253 older adults completed measures of trait forgiveness, religiosity, and health. Trait forgiveness fully mediated associations between prayer and intrinsic religiosity with illness symptoms and 5 dimensions of successful aging. In Study 3, 80 middle-aged men and women completed state and trait forgiveness measures, as well as religiosity and health measures. State forgiveness fully mediated the relationships between existential well-being and both symptoms and medications, and trait forgiveness fully mediated the relationship between religious well-being and both intrinsic religiosity and quality of sleep. State forgiveness partially mediated the relationships between spirituality and both sleep and depression. Within adults, unselected with regard to religious affiliations or beliefs, a variety of religious variables, health outcomes, and forgiveness measures were interrelated. In the majority of cases, forgiveness either partially or fully mediated the religion–health relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

4.
Analysis of amount of publication by Associates of the APA between 1946 and 1953 indicates an increasing rate which by 1958 would require at least a doubling in size of the journals published by the Association. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

5.
《Acta Metallurgica》1988,36(9):2393-2397
In this series of papers, the constitutive equations used to analyze concurrent shear and densification are critically evaluated. In Part I, it is shown that the sintering materials are not linearly viscoelastic, so Laplace transform techniques cannot be applied. This is not a serious limitation, however, because the relevant deformation of the matrix can be treated as purely viscous flow. Assuming that the strains produced by sintering and applied stresses are linearly additive, a simple constitutive equation is obtained. This will be compared with other constitutive equations from the literature in Part II.  相似文献   

6.
《Acta Metallurgica》1986,34(3):415-424
Theory of diffraction from h.c.p. crystals undergoing martensitic transformation to the f.c.c. structure through a non-random insertion of deformation faults is developed. From a comparison of the theoretically predicted diffraction effects with those experimentally observed on single crystals of ZnS, it is shown that the thermally induced transformations in this material are growth controlled while the deformation induced transformation is nucleation controlled.  相似文献   

7.
《Acta Metallurgica》1986,34(3):405-413
A new approach based on diffraction evidence for the involvement of shear at the atomic level is proposed to elucidate the mechanism of the f.c.c. to h.c.p. martensitic transformation. This approach is based on the analysis of the intensity distribution along streaked reciprocal lattice rows observed on diffraction patterns recorded from partially transformed f.c.c. crystals. The relevant theory of diffraction from crystals undergoing f.c.c.-h.c.p. transformation by non-random insertion of deformation faults is developed. This approach, as distinct from the conventional microstructural approach, can be especially useful in situations where the transformation strains are self accommodating in nature, such that there is no observable surface relief effect.  相似文献   

8.
前言周期表中的Ⅳ-a族元素和稀土族元素与Al一样,在化学上是非常活泼的元素,在冶炼上作为钢水脱氧剂或净化剂,是极重要的元素。此外,Ⅳ-a族元素由于在钢中能形成具有适当溶解度的碳化物,V-a族元素能形成碳化物和氮化物,因而可以说在新钢种的设计和材质的改善和提高方面,在材料学上也是非常有意义的元素,钢铁冶炼方面与这些元素有关的基础  相似文献   

9.
《Acta Metallurgica Materialia》1992,40(12):3475-3495
Two-dimensional Monte Carlo simulations of recrystallization have been carried out in the presence of incoherent and immobile particles for a range of different particle fractions, a range of stored energies and a range of densities of potential nuclei (embryos). For stored energies greater than a critical value (H/J > 1) the recrystallization front can readily pass the particles leading to a random density of particles on the front and a negligible influence of particles on the recrystallization kinetics. At lower stored energies the particles pin the recrystallization front leading to incomplete recrystallization. However at very low particle fractions, when the new grain has grown much larger than the matrix grains, before meeting any particles, the new grains can complete the consumption of the deformed grains giving complete “recrystallization” by a process that appears to be similar to abnormal grain growth. Particles are, as reported previously, very effective at pinning grain boundaries, both of the deformed and recrystallized grains, when boundaries migrate under essentially the driving force of boundary energy alone. Such boundaries show a density of particles that rises rapidly from the random value found at the start of the simulation. As a consequence, particles very strongly inhibit normal grain growth after recrystallization. Such growth can only occur if the as-recrystallized grain size is less than the limiting grain size seen in the absence of recrystallization. Under these circumstances a small increment of grain growth occurs until the grain boundaries once again acquire a higher than random density of particles.  相似文献   

10.
The self consistent model of Molinari et al.[Acta metall.35, 2983 (1987)] is modified with the help of the finite element results of Gilormini and Germain [Int. J. Solids Struct., 23, 413 (1987)]. The modification implies the introduction of a new scalar parameter in the interaction law of the self consistent model. In this first part, the model is established and the new parameter is tuned so that the self consistent predictions and the results of the finite element predictions for a spherical inclusion in an infinite matrix nearly coincide. A simple relation between the new parameter and the value of the strain rate sensitivity has been found.  相似文献   

11.
《Acta Metallurgica》1984,32(3):423-434
A quantitative study of cavitation damage and fracture of a superplastic copper alloy, Coronze 638, has been made. Cavities are found to nucleate at large particles present in the form of stringers. The size and shape of cavities, as well as the level of damage up to fracture are essentially independent of strain rate over regions I and II of the σ−ϵ curve, as are the true strain to fracture and the development of t instabilities. As the strain rate increases into region III, the level of damage to failure decreases, while the true failure strain increases and necks become sharper. Extensive cavity coalescence is observed up to strains of about 1.5, producing a number of large (> 100 μm) cavities which exhibit a high stability, and little tendency to coalescence. This allows the sample to sustain a very high level of cavitation without failure. The mechanism of cavity growth for small isolated cavities (< 10 μm) is thought to be diffusive growth constrained by matrix creep at low strain rates, with a transition to plasticity controlled growth at large strain rates. For larger cavities growth appears to be entirely creep controlled. Final fracture occurs by the material exhaustion in the ligaments between voids once the reduction in the cross section exceeds about 30%. No large instability either in flow or damage seems to be involved in this process.  相似文献   

12.
《Acta Metallurgica Materialia》1993,41(12):3473-3482
A computer model of fatigue crack nucleation, based on the concept of random slip, has been developed with guidance from surface observations of slip behavior within a persistent slip band (PSB), using bright field viewing and interferometry. The observations provide direct experimental determination of the parameters needed in the model. The computer simulations show that crack nucleation, defined as an intrusion of 4 μm depth, occurs in good agreement with the observed number of cycles, and that the generated PSB profiles agree well in appearance with those of real PSB's. The model also can account (indirectly) for crack nucleation at PSB edges, as is often observed, when local strain variations within actual PSB's are considered; the local strain tends to be higher at the edges of PSB's. It is shown that earlier model of crack nucleation based on random slip can be rehabilitated if up-to-date understanding on slip behavior is taken into consideration.  相似文献   

13.
14.
Presents a critical analysis of the 3rd edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-III). Improvements over DSM-II are acknowledged; it is suggested, however, that problems with larger issues (e.g., multiaxial, diagnosis, operational criteria, and the medical model) overshadow these positive features. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
Consistent with a positive psychology perspective, this longitudinal study investigated relations between positive and negative nonwork experiences (i.e., feeling recovered, thinking about the positive and negative aspects of one’s work during leisure time) with different job performance dimensions. In total, 358 employees working with persons with special needs responded to two questionnaires at an interval of 6 months. Results from hierarchical regression analyses showed that feeling recovered during leisure time predicted an increase in task performance after 6 months. This relation was mediated by occupational self-efficacy. Positive work reflection was found to predict an increase in proactive behavior (personal initiative, creativity) and organizational citizenship behavior. Negative work reflection was unrelated to job performance. Our results emphasize the role of positive nonwork experiences for employees’ job performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
MR.WU JIANCHANG WAS AP-POINTED THE PRESIDENT OF CHI-NA NATIONAL NONFERROUSMETALS INDUSTRY CORPORA-TION (CNNC) AS OF SEPTEMBER19,1994 BY THE STATE COUNCILOF THE PEOPLE'S REPUBLIC OFCHINA;AT THE SAME TIME,MR.FEI ZEIWEN WAS REMOVEDFROM THE POSITION.  相似文献   

17.
Sport participation among children and youth is ubiquitous in U.S. society. As such, it is imperative to understand how and under what conditions youth engagement in organized sport promotes or interferes with development. Each article in this special section has a unique lens on sport programs and advances our understanding about the contributions of individual characteristics, features of the context, and the process between the two that leads to different developmental trajectories for youth. In combination, the perspectives and findings provided in these articles can help guide future research and the development of programs and interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
Although positive emotion research has begun to flourish, the extremes of positive emotion remain understudied. The present research used a multimethod approach to examine positive emotional disturbance by comparing participants at high and low risk for episodes of mania, which involves elevations in positive emotionality. Ninety participants were recruited into a high or low mania risk group according to responses on the Hypomanic Personality Scale. Participants' subjective, expressive, and physiological emotional responses were gathered while they watched two positive, two negative, and one neutral film clip. Results suggested that participants at high risk for mania reported elevated positive emotion and irritability and also exhibited elevated cardiac vagal tone across positive, negative, and neutral films. Discussion focuses on the implications these findings have for the diagnosis and prevention of bipolar disorder, as well as for the general study of positive emotion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
《Acta Metallurgica》1982,30(1):251-255
An electrochemical cell method has been used to measure the diffusivity of hydrogen in Pd-Au solid solutions in the temperature range 273–360 K and in the concentration range 1–50 at.% Au. Up to 10 at.% Au the mobility of H in the metal lattice is virtually unaffected by the presence of Au in the solid solution. There is then an increase in mobility with increasing Au-concentration.This phenomenon has been interpreted in terms of a statistical model in which interstitial sites adjacent to Au atoms act as antitraps.  相似文献   

20.
《Acta Metallurgica》1982,30(1):245-250
Elastic data have been measured for Pd-based solid solutions containing Cu, Au, and Ag in the concentration range 0–50 at.% of substitutional solute and in the temperature range 300–1200 K.The elastic data have been used to evaluate a statistical mechanical model for solid solutions of hydrogen in Pd-based solutions containing noble metals. The elastic data are used to calculate that contribution to the partial thermodynamic functions of the dissolved interstitial atoms which arises due to the change in the specific volume of the metal lattice as the substitutional atom concentration is varied.  相似文献   

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