Geometry of shadows

Shadows provide a strong source of information about the shapes of surfaces. We analyze the local geometric structure of shadow contours on piecewise smooth surfaces. Particular attention is paid to intrinsic shadows on a surface: that is, shadows created on a surface by the surface's own shape and placement relative to a light source. Intrinsic shadow contours provide useful information about the direction of the light source and the qualitative shape of the underlying surface. We analyze the invariants relating surface shape and light-source direction to the shapes and singularities of intrinsic shadow contours. The results suggest that intrinsic shadows can be used to directly infer illuminant tilt, qualitative global surface structure, and, at intersections with surface creases, the concavity/convexity of a surface. We show that the results obtained for point sources of light generalize in a straightforward way to extended light sources, under the assumption that light sources are convex.     

Normality and projective techniques.

The major purpose of this article is to point out how the concept of normality has been used and misused in research with projective techniques at the present time. 18 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Intrapsychic outcome in projective identification

Four possible outcomes of projective identification (Klein, 1946) are identified. First is a parallel sending, receiving, and giving back between both parties. Second, there is an inability to access the receiver, leading to annihilation anxieties. Third is an experience of the receiver not being able to process the message, leading to the sender's fantasy of hurting or destroying the object. Finally, there is the experience of the object becoming outraged at being asked to receive a message and subsequently attacking the sender. These are all fantasy states that come about in the context of the most basic of human communications, the process of projective identification. Projective identification is a fantasy-dominated experience and a dialectical process within both interpersonal and intrapsychic forums. These four potential states are separated for theoretical purposes but are always cross-influencing and creating each other in the unconscious. The situations described between mother and infant are paralleled in the analytic situation, the difference being the chronological and developmental passage of time and the evolution of the original fantasy material.     

Geometry of grain boundaries

The first part of this paper deals with the problem of describing and measuring microstructure in exact terms. The Euclidean parameters: volume, area, length, and angle can be measured and expressed only in terms of the total of each in unit volume. Average properties, such as average grain diameter, are accessible only through the topological parameters, specifically number in unit volume, which can be measured only by serial sectioning. The parameters which have been used to represent the concept of grain size are analyzed and shown in most cases to represent a function of grain boundary area. In a second section of this paper the geometric problem of plastic slip through a grain boundary is analyzed. A method is proposed by which all of the components of the deformation, as well as the crystallographic directions, can be manipulated simultaneously through the use of a stereographic projection. The third section of this paper is concerned with the geometry of grain growth. The polycrystalline state is described as a grain boundary network, which must respond to the requirements of surface tension. The several topological changes in a network which can contribute to grain growth are described.     

On the classification of projective techniques.

Projective tests may be classified in 6 different ways: attributes of the test material itself; techniques employed in constructing the test (rational vs. empirical); manner of interpreting the test (i.e., formal analysis vs. content analysis); purpose of the test; differences in the administration of the test (i.e., group vs. individual); type of response they elicit (i.e., story construction vs. association). Though all the classification schemas have merit it is argued that the "type of response" approach is most likely to be closely related to the actual psychological process involved in the test since this points to what the S is actually doing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Assessment of annihilation anxiety from projective tests

This report details procedures to measure annihilation anxiety, a concept derived from Freud's 1926 formulation of traumatic anxiety. A 25-item pencil-and-paper inventory administered to patient and to nonpatient samples is described, along with a brief summary of earlier findings. The delineation of nine interrelated experiential components of annihilation anxiety provides the background for the construction of Rorschach and TAT measures of the concept. Findings comparing the pencil-and-paper inventory and the projective test measures are presented as well as examples of responses judged to reflect annihilation anxiety from Rorschach and TAT protocols.     

Borderline diagnosis in projective assessment.

Reviews 36 publications on projective testing of borderlines to determine the extent to which the disorder can be defined. The data show that although borderlines can be distinguished as a group from neurotics and schizophrenics, the differences are small, and there is considerable overlap among these diagnostic groups. No specific psychological mechanisms have been identified that typify borderlines and are not also found among neurotics, schizophrenics, or both. These findings imply that borderline pathology cannot be exclusively attributed to trauma from any particular period of development and that no specifically focused therapeutic approach is appropriate for most borderlines. Theoretical and technical approaches helpful for borderlines are also helpful for at least some neurotics and psychotics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Direct versus projective measurement of achievement motivation.

Tested the predictive validity of 3 techniques for measuring need for achievement (n Ach): (1) TAT projection (scored in 2 ways), (2) Ss' self-reports on a rating scale, and (3) 2 self-peer ranking measures. Ss were 72 male undergraduates. In the self-peer ranking measures, each S listed 10 of his friends and then rated himself in relation to each friend. The criterion measures were class grades and 2 short laboratory tasks. Neither the scores derived from the TAT protocols nor the rating scale self-reports were related to any criterion measure. Both of the self-peer ranking scores were significantly correlated with grades. It was concluded that n Ach was conscious and subject to direct self-report if the means of responding is made specific. (20 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Situational effects on a projective test.

"The Rosenzweig Picture-Frustration Study was administered to 154 engineers and accountants. The test booklets of a comparable sample of 60 engineers and accountants who had taken the Rosenzweig as part of an appraisal procedure in a psychological consulting organization were scored in an equivalent manner to those of the survey sample." Those who took the test anonymously showed much less impunitiveness. From Psyc Abstracts 36:04:4HG86M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Body sensation and perception of projective stimuli.

2 studies were carried out to test the general hypothesis that body experience may influence responses to projective stimuli. Specifically, it was proposed that the more aware an individual is of his stomach the more frequently he will produce stomach-related themes (e.g., nutritive) when imaginatively elaborating inkblots. Stomach awareness was measured by means of a technique which involves comparing the prominence of one's own stomach with a series of other paired body sectors. Studies 1 and 2 involved 102 and 93 Ss, respectively. In both instances there was significant support for the hypothesis. The findings suggest that body experiences may play a meaningful role in the individual's response to various types of unstructured stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Bias in postdiction from projective tests.

"These results, within the limitations imposed by the particular array of test items and by the generalizability of results obtained from the study of a single person, suggest that the data of projective tests predispose toward an over-estimation of maladjustive trends in postdiction situations." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Some shortcomings in projective test validation.

"This paper has sought to demonstrate that the negative or inconclusive results obtained in many validity studies of projective techniques are, in part at least, determined by important defects in the experimental conceptualization of the problem. The major deficiencies noted were (a) a tendency to ignore the significant avoidant aspects of behavior as reflected in the test data, and (b) a failure to recognize the importance of the generalization gradient from test to predictive situation as a relevant variable affecting predictive accuracy." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Art and science in projective techniques.

Many psychologists seem to feel that lacunae exist between the scientific and utilitarian status of projective techniques. They may either condemn projective techniques for their apparent lack of scientific validity or excessively praise them for their ability to generate artistic and intuitive meaning. The gap between science and art is not irreconcilable. Long ago, Leonardo da Vinci pointed out that sublime art could not occur unless the artist carefully and patiently studied the sciences that pertain to art. For Leonardo there was no immutable division between art and science, and he further felt that good science made for great art. Leonardo's propositions about art and science can also be applied to the field of projective techniques. Careful precision, rigor, and specification (science) has, and can continue to lead to conclusions that are extremely useful in terms of the practical application of projective techniques (art). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Downstream Hydraulic Geometry of Alluvial Channels

This study extends the earlier contribution of Julien and Wargadalam in 1995. A larger database for the downstream hydraulic geometry of alluvial channels is examined through a nonlinear regression analysis. The database consists of a total of 1,485 measurements, 1,125 of which describe field data used for model calibration. The remaining 360 field and laboratory measurements are used for validation. The data used for validation include sand-bed, gravel-bed, and cobble-bed streams with meandering to braided planform geometry. The five parameters describing downstream hydraulic geometry are: channel width W, average flow depth h, mean flow velocity V, Shields parameter τ*, and channel slope S. The three independent variables are discharge Q, median bed particle diameter ds, and either channel slope S or Shields parameter τ* for dominant discharge conditions. The regression equations were tested for channel width ranging from 0.2 to 1,100?m, flow depth from 0.01 to 16?m, flow velocity from 0.02 to 7?m/s, channel slope from 0.0001 to 0.08, and Shields parameter from 0.001 to 35. The exponents of the proposed equations are comparable to those of Julien and Wargadalam (1995), but based on R2 values of the validation analysis, the proposed regression equations perform slightly better.     

Bed-Form Geometry in Sand-Bed Flows

A new method is proposed for predicting relative bed-form height h∕d in sand-bed flows. The proposed method is based on the concept of relating energy loss due to form drag to the head loss across a sudden expansion in open channel flows. A unique feature of the proposed method is that it can be applied to various bed forms, i.e., ripples, dunes, antidunes∕standing waves, and transitional bed regimes that occur in alluvial flows. The relation thus developed was applied to a large number (251 flows, 14 different data sets) of laboratory and river data, and was found to give good agreement with the observed h∕d values. In a comparison of prediction accuracies with seven existing relationships, the proposed method was found to give significantly better agreements with the observed data. Future improvements in the prediction of h∕d will depend on improved formulations of the two parameters incorporated in the present relation, i.e., energy loss coefficient K, and the relative bed-form length L∕d for various bed configurations. More research is needed to develop better formulations for these parameters.