Fast polygonal approximation of digitized curves

We describe a new technique for fast “scan-along” computation of piecewise linear approximations of digital curves in 2-space. Our method is derived from earlier work on the theory of minimum-perimeter polygonal approximations of digitized closed curves.We demonstrate the specialization of this technique to the case where the error is measured as the largest Hausdorff-Euclidean distance between the approximation and the given digitized curve. We illustrate the application of this procedure to the boundaries of the images of a lung and a rib in chest radiographs.     

Relation of triglycerides to phosphoglycerides in fungi

Lipids of the fungiPhycomyces blakesleeanus, Lipomyces lipoferus, Glomerella cingulata andCoprinus comatus have been analyzed by physical and chemical methods. Triglycerides were the largest fraction of all the lipids in these fungi but significant amounts of phosphoglycerides were also present. The presence of relatively large amounts of triglycerides and phosphoglycerides, and the fatty acid patterns of these glycerides, suggests that formation of the tri- and phosphoglycerides involves participation of key intermediates from a common pathway of synthesis. The triglycerides ofGlomerella cingulata have been studied in more detail than those of the other species. It has been found, using preparative thin-layer chromatography and analytical gas-liquid chromatography, thatG. cingulata triglycerides comprise one fraction of saturated and monoenoic fatty acids, another fraction of saturated, mono-, and dienoic acids and two fractions containing varying proportions of saturated, mono-, di-, and trienoic fatty acids.     

An illusory interpretation of the first factor of the MMPI: A reply to Shweder.

Critically evaluates R. A. Shweder's (see record 1978-20144-001) reinterpretation of the meaning of the 1st factor of the MMPI. The solitary coefficient on which he predicates his reinterpretation is shown to be heightened as a function of sample selection, the pooling of judgments when individual judgments are appropriate, and the particular mix of MMPI scales analyzed. Further, Shweder's rationale for his interpretation depends on the factually incorrect assumption of high interrelationships among MMPI items. Finally, Shweder's reinterpretation of the 1st factor of the MMPI offers no explanation whatsoever for the existence of individual differences in response to the questionnaire nor does it explain the many correlates of the MMPI and related questionnaires to real-world criteria. Until this reinterpretation can be extended to apply to the broadly ranging criterion correlates of personality inventories, it is of little interest. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The TRIUMF Time Projection Chamber Data Acquisition System

The Time Projection Chamber (TPC) at TRIUMF was developed for the search for muon-electron conversion, a lepton number violating process. This paper describes the data acquisition system in use for the last two years. Basic components of the system are a multi-crate CAMAC acquisition system, external memory, PDP 11/40 and VAX 11/780 coupled through DECNET. A discussion of the various software packages for data-taking and on-line track reconstruction follows.     

ON THE RECURSIVE FITTING OF SUBSET AUTOREGRESSIONS

Abstract. In fitting a vector autoregressive process which may include lags up to and including lag K , we may wish to search for the subset vector autoregressive process of size k (where k is the number of lags with non-zero coefficient matrices, k = 1, 2, K ) which has the minimum generalized residual variance. This paper provides a recursive procedure, which is initialized by evaluating all 'forwardand'backward' autoregressions in which k = 1. The recursion then allows one to develop successively all subsets of size k = 2, k = 3 up to k = K .
The optimum subset vector autoregression is found by employing the proposed recursive procedures in conjunction with model selection criteria. This approach is used on simulated data to assess its performance and to re-examine the annual trappings of the Canadian lynx investigated by Tong (1977).     

Training family physicians in behavioral aspects of primary care: The psychologist's role.

Describes a comprehensive system for training general practice residents to integrate behavioral science knowledge into all aspects of their work. This system provides guidelines for information gathering, goal-oriented assessment, and treatment planning. A program used to train residents in this system is outlined. Results of a study evaluating this training show that residents were able to incorporate only the diagnostic phase of the system. Implications are discussed for the psychologist faculty member's role in such training. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Durability and generalizability of persistence training.

40 male and 40 female college students experienced either partial reinforcement (persistence training) or continuous reinforcement on either of 2 instrumental tasks (finger shuttle or button press) as therapy for failure-induced depression and subsequently were exposed to protracted failure (extinction). Following this initial extinction phase all Ss received continuous reinforcement on a common instrumental task (button press) as therapy and then encountered extinction (consecutive failure trials) for a 2nd time. Results show that increased persistence occasioned by partial-reinforcement therapy was able to survive interpolated periods of extinction and continuous reinforcement; that is, durable persistence training effects were shown. Furthermore, persistence training effects were shown to be generalizable (the persistence advantage associated with partial-reinforcement therapy transferred across topographically different responses), but the generalization process was not a complete one. The results are discussed within the frameworks of frustration theory and alternative cognitive theories. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Behavioral effects of a noisy environment: Task involvement versus passive exposure.

Compared the effects of noise under active task involvement as opposed to passive exposure, using 80 undergraduate Ss who were assigned to 1 of 4 conditions representing 2 * 2 combinations of task vs no task and noise vs quiet. Performance on a dial-monitoring task was unaffected by noise. Ratings of interest and tenseness were significantly higher under the task condition; tenseness was also higher under noise. On a posttest of resistance to frustration, both noise groups, regardless of task condition, showed a smaller degree of persistence on insoluble puzzles than the no-noise groups. Results suggest that aftereffects of noise are not dependent on the power of noise to disrupt task performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interpersonal behavior of depressive individuals in a mixed-motive game.

100 undergraduates were selected as Ss on the basis of their scores on the Beck Depression Inventory, a short form of the MMPI, and the Fear Survey Schedule. Three groups of Ss (depressed, nondepressed/other psychological problems, and normal) interacted with a same-sex normal person in a modified Prisoner's Dilemma procedure in which each player's relative power was manipulated. Dyads also had several opportunities to exchange communications during the game. Results indicate that when depressed Ss were in the high-power role, the interactive pattern in the Prisoner's Dilemma procedure was relatively exploitive and noncooperative. High-power depressed Ss also displayed elevation in communications of self-devaluation/sadness and helplessness. This array of behaviors elicited noncooperativeness, extrapunitiveness, and expressions of helplessness in their normal partners. Depressives in the low-power role exhibited no unique game behaviors but communicated self-devaluation and helpless messages; and in addition, they tended to blame their partner for their devalued condition—a pattern that elicited more ingratiating behaviors in their normal partners. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)