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991.
HIPS (Human Information Processing Laboratory’s Image processing System) is a software system for image processing that runs under the UNIX operating system. HIPS is modular and flexible: it provides automatic documentation of its actions, and is relatively independent of special equipment. It has proved its usefulness in the study of the perception of American Sign Language (ASL). Here, we demonstrate some of its applications in the study of vision, and as a tool in general signal processing. Ten examples of HIPS-generated stimuli and—in some cases—analyses are provided, including the spatial filtering analysis of two types of visual illusions; the study of frequency channels with sine-wave gratings and band-limited noise; 3-dimensional perceptual reconstruction from 2-dimensional images in the kinetic depth effect; the perception of depth in random dot stereograms and cinematograms; and the perceptual segregation of objects induced by differential dot motion. Finally, examples of noise-masked, cartoon coded, and hierarchically encoded ASL images are provided.  相似文献   
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Psychophysical thresholds for the detection of vibration delivered to the thenar eminence of the right hands of young males and females were measured every other day for 30–34 days. The frequency of the vibratory stimulus was either 15 or 250 Hz. The sinusoidal stimuli applied through a 3.0-cm2 contactor were 700 msec in duration and had rise-fall times of 25 msec. Stimulus amplitude was measured with a calibrated accelerometer mounted on the moving element of the vibrator. Data were plotted as a function of successive days in the menstrual cycle. Thresholds for detecting the 15-Hz stimulus did not change significantly, whereas thresholds for detecting the 250-Hz stimulus varied significantly over the menstrual cycle. The 250-Hz threshold became progressively lower as subjects approached the onset of menstruation. After the onset of menstruation, the 250-Hz threshold gradually increased, reaching a maximum value approximately 12 or 13 days later. Soon after the 12th or 13th day of the cycle, the threshold again began to decline and continued to decline until the onset of the next menstrual cycle. The thresholds of women taking birth control pills did not change systematically over the testing period.  相似文献   
993.
A least-squares algorithm for fitting ultrametric and path length or additive trees to two-way, two-mode proximity data is presented. The algorithm utilizes a penalty function to enforce the ultrametric inequality generalized for asymmetric, and generally rectangular (rather than square) proximity matrices in estimating an ultrametric tree. This stage is used in an alternating least-squares fashion with closed-form formulas for estimating path length constants for deriving path length trees. The algorithm is evaluated via two Monte Carlo studies. Examples of fitting ultrametric and path length trees are presented.G. De Soete is Aspirant of the Belgian Nationaal Fonds voor Wetenschappelijk Onderzoek at the University of Ghent, Belgium. W. S. DeSarbo and J. D. Carroll are Members of Technical Staff at AT&T Bell Laboratories, Murray Hill, N.J. G. W. Furnas is Member of Technical Staff at Bell Communications Research, Murray Hill, N.J.  相似文献   
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Differences between academic and nonacademic psychologists may be viewed as immutable, worthy of encouragement, or as a situation which the latter group must remedy by becoming “more scientific.” We contend that for community psychology, which perceives theory, application, and action as valid aspects of its broad paradigm, it would be most adaptive toexplicitly address the challenge of managing a balance between diversity and cohesion. There are signs that the present leadership of Division 27 recognizes aspects of this problem and is reconsidering the role and purpose of the Division as an organizing framework for the discipline (Trickett, Note 3). It is our view that engendering a commitment from various subgroups within the membership to addressing the disparities revealed by our respondents is required for resolving what we see as major obstacles to future development of the discipline. The conceptual and empirical approach presented in this study can be an important tool in forging constructive solutions to the challenges we have presented.  相似文献   
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Spirituality is a significant factor in recovery from alcoholism, whatever definition of this condition one may use. One aspect of alcohol abuse is its apparent relationship to the balance between brain hemispheres. Excessive use of alcohol anesthetizes the object-based, language-oriented functions of the left hemisphere, associated with an action mode of consciousness. This allows greater engagement of the right-hemisphere receptive mode, which is also associated with religious experience. A model of spirituality based on achieving a balance between hemisphere functions and modes of consciousness could provide a non-chemical alternative to excessive use of alcohol.  相似文献   
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Lenneberg suggested that a chimpanzee's linguistic ability could be tested by presenting sentences containing two prepositional phrases joined by a conjunction. This would involve joining two semantic propositions, and thus represents a more complex test of chimpanzee syntactic competence than previously attempted. Jane, a five year-old language trained chimpanzee, was tested on her ability to both produce and comprehend sentences involving a preposition (in or behind) and a conjunction (and). The results from production and comprehension were substantially the same. Jane showed the ability to appropriately deploy and, behind and in, but displayed very little flexibility in their use. It is suggested that a chimpanzee may be able to learn some rules of syntax but is not able to be creative with that syntax.  相似文献   
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