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941.
Ernest Ropiquet Hilgard earned the Gold Medal Award as a gifted generalist, who has made scientific contributions to nearly every field of psychology, most notably in learning and states of consciousness; a deep student of psychological history and systems; a man of conscience, concerned with social issues and the applications of psychology to human welfare; a leader and statesman in social science research policy and education; and above all, a teacher, through his writings, his work with students, and his example. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
942.
943.
Presents the citation of the 1970 American Psychological Association's Distinguished Scientific Contribution Award winner, Robert Duncan Luce. The award citations reads: "For his leadership in the development of theories that range from social behavior, to learning and memory, to perception and psychophysics. By his judicious use of mathematical methods he has contributed significantly to the development of psychology as a quantitative science. The hallmark of his research has been to take an extremely simple set of axioms and explore in detail their implications for a wide range of phenomena. For example, in his theory of choice, a general axiom concerning selections from related sets of alternatives is shown to have important applications in such diverse fields as psychophysics, learning, and social utility. Mathematical theory dominates his work, but it is by no means anti-empirical; it has been a stimulus for many important experimental studies. His recent contribution to the theory of measurement has broad ramifications not only for psychology but for the general methodology of all sciences." Personal biographic information is also included, along with a list of the recipient's scientific writings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
944.
945.
Develops a time-series methodology for approaching data in a range of research settings and presents a design package using the time series as a method to eliminate major sources of rival hypotheses. A mathematical model with special considerations for application is offered which maximizes the utility of time-series data for generating and testing hypotheses. (21 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
946.
Notes that electrolytic lesions of the centrum-medianum and parafascicularis complex of the thalamus produce, in the rat, large deficits of both acquisition and retention of active-avoidance responses, especially in the 2-way shuttle-box test. The effect of such lesions on 26 male cats and 6 male and 2 female macaques was examined. It was found that lesions in the cat did not produce significant effects, either with acoustical or visual CS, during postoperative relearning. Moreover, rate of extinction was not affected. Negative results were also found in monkeys. These lesions did not modify the threshold of flinch or jump responses to electric shock in either species. (20 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
947.
On August 29, 1978, at the annual meeting of the APA in Toronto, the American Psychological Foundation announced the recipients of the Gold Medal Award, the Distinguished Contribution to Education in Psychology Award, a special award for Unique Contribution in the Teaching of Psychology, and the National Media Awards. George Albee, President of the APF, made the presentations. Ernest R. Hilgard received the Gold Medal Award; Douglas K. Candland was given the Teaching Award; and Robert S. Daniel was the recipient of the Unique Contribution in the Teaching of Psychology Award. National Media Award winners were Robert M. Stern and William J. Ray, Emily Hahn, Elizabeth Einstein, Eric Braun, and Stephen Glauber and Dan Rather. Other members of the APF are Wilbert J. McKeachie (Vice-President}, Boris E. Cherney (Treasurer), Charles A. Kiesler (Secretary), Kenneth B. Clark, Anne Anastasi, Leona E. Tyler, Albert Bandura, Donald T. Campbell, and Theodore H. Blau. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
948.
Announces changes in the list of APA-Approved Doctoral Programs in Professional (Clinical, Counseling, and School) Psychology and Predoctoral Internship Programs in Psychology. These changes update the listings published in the December 1980 American Psychologist (pp. 1111- 1118). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
949.
Assessment of elastic parameters of human skin using dynamic elastography   总被引:4,自引:0,他引:4  
Sonoelastography and transient elastography are two ultrasound-based techniques that facilitate noninvasive characterization of the viscoelastic properties of soft tissues by investigating their response to shear mechanical excitation. Young's modulus is the principle assessment parameter. Because it defines local tissue stiffness, it is of major interest for the medical imaging and cosmetic industries as it could replace subjective palpation by yielding local, quantitative information. In this paper, we describe a new high-resolution device capable of measuring local Young's modulus in very thin layers (1-5 mm) and devoted to the in vivo evaluation of the elastic properties of human skin. It uses an ultrasonic probe (50 MHz) for tracking the displacements induced by a 300 Hz shear wave generated by a ring surrounding the transducer. The displacements are measured using a conventional cross-correlation technique between successive ultrasonic back-scattered echoes. First, this noninvasive technique has been experimentally proven to be accurate for investigating elasticity in different skin-mimicking phantoms. Second, data were acquired in vivo on human forearms. As expected, Young's modulus was found to be higher in the dermis than in the hypodermis and other soft tissues.  相似文献   
950.
Electromechanical properties of (1-x)Pb (Mg1/3Nb2/3)O3-xPbTiO3 (PMN-PT) single crystals with x = 0.35 were investigated as a function of different external disturbances. The polarization dependence on the electromechanical properties was first studied in order to determine the best polarization path. The correlation with X-ray measured phase ratio is presented and shows that the maximum of electromechanical properties may be correlated with a minimum rhombohedral/tetragonal phase ratio. Temperature, stress, electric field, and time (aging) stability was studied in order to determine performance-limiting factors of these materials. The rhombohedral/tetragonal phase transition is observed on temperature (80 degrees C), inducing a decrease of the electromechanical coupling factor (from 85% to 50%); but the whole properties are recovered while returning to room temperature. Stress measurement shows a large depoling of sample for stresses above 30 MPa. The PMN-PT single crystals were found to be surprisingly stable during aging, except for mechanical and dielectric losses. The same tendency was found on alternating current (AC) electric field dependence.  相似文献   
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