Showing papers by "Purdue University published in 1986"

Gender and Helping Behavior. A Meta-Analytic Review of the Social Psychological Literature

Abstract: According to our social-role theory of gender and helping, the male gender role fosters helping that is heroic and chivalrous, whereas the female gender role fosters helping that is nurturant and caring. In social psychological studies, helping behavior has been examined in the context of short-term encounters with strangers. This focus has tended to exclude from the research literature those helping behaviors prescribed by the female gender role, because they are displayed primarily in long-term, close relationships. In contrast, the helping behaviors prescribed by the male gender role have been generously represented in research findings because they are displayed in relationships with strangers as well as in close relationships. Results from our meta-analytic review of sex differences in helping behavior indicate that in general men helped more than women and women received more help than men. Nevertheless, sex differences in helping were extremely inconsistent across studies and were successfully predicted by various attributes of the studies and the helping behaviors. These predictors were interpreted in terms of several aspects of our social-role theory of gender and helping.

Employee Turnover: A Meta-Analysis and Review with Implications for Research

Abstract: Studies of employee turnover are reviewed using meta-analytic techniques. The findings indicate that almost all of the 26 variables studied relate to turnover. The findings also indicate that study variables including population, nationality, and industry moderate relationships between many of the variables and turnover. It is suggested that future research on employee turnover: (1) report study variables, (2) continue model testing rather than simply correlating variables with turnover, and (3) incorporate study variables into future models.

Shape Discrimination Using Fourier Descriptors

Abstract: Description or discrimination of boundary curves (shapes) is an important problem in picture processing and pattern recognition Fourier descriptors (FD's) have interesting properties in this respect. First, a critical review is given of two kinds of FD's. Some properties of the FD's are given and a distance measure is proposed, in terms of FD's, that measures the difference between two boundarv curves. It is shown how FD's can be used for obtaining skeletons fobjects. Finally, experimental results are given in character recognition and machine parts recognition.

Types of Synergy and Economic Value: The Impact of Acquisitions on Merging and Rival Firms

Abstract: Summary Acquisitions, in gene-al, have been demionstrated to create economic valle. The intuitive reason ulndlerlying this value creation stems either firon an ability to redulce costs of the comtibined entity, an ability to charge higher prices, or both. Current research in the area attributes these abilities to an opportutnity to utilize a specialized resource. Oul focus in this study is to comnpare three broad classes of resources that contribute to the creation of value. Following the conventionial wisdom, these r esouirces are classified as cost of capital related (resullting in financial syneergy), cost of production related (resuilting in operational synergy), anid price related (resulting in collusive synergy). Given the limitations of our sample and research design, we find that collusive synergy is, on average, associated with the highest value. Furthem; the resoulrces behind financial synergy tend to create mnore value than the resouirces behind operational synergy.

Stack filters

Abstract: The median and other rank-order operators possess two properties called the threshold decomposition and the stacking properties. The first is a limited superposition property which leads to a new architecture for these filters; the second is an ordering property which allows an efficient VLSI implementation of the threshold decomposition architecture. Motivated by the success of rank-order filters in a wide variety of applications and by the ease with which they can now be implemented, we consider in this paper a new class of filters called stack filters. They share the threshold decomposition and stacking properties of rank-order filters but are otherwise unconstrained. They are shown to form a very large class of easily implemented nonlinear filters which includes the rank-order operators as well as all compositions of morphological operators. The convergence properties of these filters are investigated using techniques similar to those used to determine root signal behavior of median filters. The results obtained include necessary conditions for a stack filter to preserve monotone regions or edges in signals. The output distribution for these filters is also found. All the stack filters of window width 3 are determined along with their convergence properties. Among these filters are found two which we have named asymmetric median filters. They share all the properties of median filters except that they remove impulses of one sign only; that is, one removes only positive going edges, the other removes only negative going edges, while the median filter removes impulses of both signs. This investigation of the properties of stack filters thus produces several new, useful, and easily implemented filters.

Reflectance properties of soils

Abstract: Publisher Summary This chapter discusses the reflectance properties of soils. In delineating differences among soils and in describing the characteristics of a soil profile, color is one of the most useful attributes for documenting these differences. Soil visible reflectance, or color, is a differentiating characteristic for many classes in all modern soil classification systems and is an essential part of the definitions for both surface and subsurface diagnostic horizons. The chapter includes instrumentation for reflectance measurements. Instruments that are used to measure the reflectance of soil are divided into two broad classes—namely, spectroradiometers and multiband radiometers. Multiband radiometers contain several optical filters to define the spectral bandpasses. These spectral bandpasses are selected to sample discrete portions of the optical spectrum, e.g., the Landsat multispectral scanner or the thematic mapper bands. The character of reflected light from a soil surface depends on the nature of the surface and the intensity and spectral quality of the radiation incident upon the surface. The soil surface may be irradiated by direct sunlight, scattered skylight, and thermal radiation from the surroundings.

On the Cahn-Hilliard equation

Abstract: where y, Yl and )'2 are constants with y > 0, arises in the study of phase separation in cooling binary solutions such as alloys, glasses and polymer mixtures; see CAHN & HILLIARD [1958], NOVICK-COHEN & SEGEL [1984], NOVICK-COHEN [1985] and the references cited therein. Here u(x, t) is a perturbation of the concentration of one of the phases and (1-1 a) is the equation of conservation of mass with the mass flux J being 0 [ 02U] or-Ox 9(u) -y~--~x2j. (1-2)

Melting and Solidification of a Pure Metal on a Vertical Wall

Abstract: Etude experimentale de l'ecoulement de convection naturelle dans la phase liquide et de son influence sur le mouvement de l'interface liquide-solide et sur le transfert de chaleur au cours de la fusion et de la solidification de gallium a haute purete sur une paroi verticale

Partitioning and Mapping Algorithms into Fixed Size Systolic Arrays

Abstract: A technique for partitioning and mapping algorithms into VLSI systolic arrays is presented in this paper. Algorithm partitioning is essential when the size of a computational problem is larger than the size of the VLSI array intended for that problem. Computational models are introduced for systolic arrays and iterative algorithms. First, we discuss the mapping of algorithms into arbitrarily large size VLSI arrays. This mapping is based on the idea of algorithm transformations. Then, we present an approach to algorithm partitioning which is also based on algorithm transformations. Our approach to the partitioning problem is to divide the algorithm index set into bands and to map these bands into the processor space. The partitioning and mapping technique developed throughout the paper is summarized as a six step procedure. A computer program implementing this procedure was developed and some results obtained with this program are presented.

Differences between the mechanism of action of MDMA, MBDB, and the classic hallucinogens. Identification of a new therapeutic class: entactogens.

Abstract: (1986). Differences Between the Mechanism of Action of MDMA, MBDB, and the Classic Hallucinogens. Identification of a New Therapeutic Class: Entactogens. Journal of Psychoactive Drugs: Vol. 18, MDMA: Proceedings of the Conference, pp. 305-313.

Affect intensity and reactions to daily life events.

Abstract: Deux etudes effectuees aupres de 249 sujets examinent les differences individuelles dans l'intensite de la reponse affective a des niveaux identiques de stimulation declenchant une emotion

The site of attachment in human rhinovirus 14 for antiviral agents that inhibit uncoating

Abstract: WIN 51711 and WIN 52084 are structurally related, antiviral compounds that inhibit the replication of rhino (common cold) viruses and related picornaviruses. They prevent the pH-mediated uncoating of the viral RNA. The compounds consist of a 3-methylisoxazole group that inserts itself into the hydrophobic interior of the VP1 beta-barrel, a connecting seven-membered aliphatic chain, and a 4-oxazolinylphenoxy group (OP) that covers the entrance to an ion channel in the floor of the "canyon." Viral disassembly may be inhibited by preventing the collapse of the VP1 hydrophobic pocket or by blocking the flow of ions into the virus interior.

Entrepreneurship and paths to business ownership

Abstract: Alternative paths to ownership are examined, including starting, purchasing or inheriting a firm, as well as being promoted or brought in by existing owners. It is hypothesized that these involve different ‘degrees of entrepreneurship’, which will be reflected in the profiles of owner-managers who have followed each path. Data on 1756 owner-managers are used to test hypotheses relating path to ownership to: the entrepreneurs' background characteristics; motivations and attitudes; and previous careers, incubator organizations and processes of starting.

Credit Cards as Spending Facilitating Stimuli A Conditioning Interpretation

Abstract: Four experiments and one study were conducted to test the hypothesis that stimuli associated with spending can elicit spending responses. In all experiments, credit card stimuli were either present or absent in situations in which subjects were given an opportunity to spend. Credit card stimuli directed spending such that the probability, speed, or magnitude of spending was enhanced in the presence of credit card cues. A conditioning explanation was used to interpret the results.

A Model-Based Method for Rotation Invariant Texture Classification

Abstract: This paper presents a new model-based approach for texture classification which is rotation invariant, i.e., the recognition accuracy is not affected if the orientation of the test texture is different from the orientation of the training samples. The method uses three statistical features, two of which are obtained from a new parametric model of the image called a ``circular symmetric autoregressive model.'' Two of the proposed features have physical interpretation in terms of the roughness and directionality of the texture. The results of several classification experiments on differently oriented samples of natural textures including both microtextures and macrotextures are presented.

Aeroelastic tailoring - Theory, practice, and promise

Abstract: Aeroelastic tailoring technology is reviewed with reference to the historical background, the underlying theory, current trends, and specific applications. The specific application discussed include the Transonic Aircraft Technology program, an Advanced Design Composite Aircraft, the Wing/Inlet Advanced Development program, and the forward-swept wing. Finally, the future of aeroelastic tailoring and the development of an aeroelastic tailoring analysis and design tool under the Automated Strength-Aeroelastic Design program are examined.

Reanalysis of the Eo uml tvös experiment

Abstract: We have carefully reexamined the results of the experiment of E\"otv\"os, Pek\'ar, and Fekete, which compared the accelerations of various materials to the Earth. We find that the E\"otv\"os-Pek\'ar-Fekete data are sensitive to the composition of the materials used, and that their results support the existence of an intermediate-range coupling to baryon number or hypercharge.

Burst detection with single-point velocity measurements

Abstract: An evaluation of the effectiveness of the VITA, Quadrant, TPAV, U -level, Positive slope, and VITA with slope burst-detection algorithms has been done by making direct comparisons with flow visualization. Measurements were made in a water channel using an X-type hot-film probe located in the near-wall region. Individual ejections from bursts which contacted the probe were identified using dye flow visualization. The effectiveness of each of the detection algorithms was found to be highly dependent on the operational parameters, i.e. threshold levels and averaging or window times. These parameters were adjusted so that the number of events detected by each of the algorithms corresponded to the number of ejections identified by flow visualization, while the probability of a false detection was minimized. Comparing the detection algorithm using these optimum parameter settings, the Quadrant technique was found to have the greatest reliability with a high probability of detecting the ejections and a low probability of false detections. Furthermore, it was found that the ejections detected by the Quadrant technique could be grouped into bursts by analysing the probability distribution of the time between ejections.

Dependence of energy gap on x and T in Zn 1 − x Mn x Se: The role of exchange interaction

Abstract: Photoluminescence and reflectivity measurements have been carried out on ${\mathrm{Zn}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{Mn}}_{\mathrm{x}}$Se solid solutions in the complete range of crystal compositions, 0\ensuremath{\le}x\ensuremath{\le}0.55. The features of the photoluminescence and reflectivity data near the band edge enabled us to determine values of the fundamental band gap as a function of Mn molar fraction x and temperature (8 K\ensuremath{\le}T\ensuremath{\le}300 K). The energy gap in crystals with compositions in the vicinity of the zinc-blende--wurtzite structural transition (0.2\ensuremath{\lesssim}x\ensuremath{\lesssim}0.3) exhibited a scatter of values, probably associated with the presence of various polytypes (as evidenced by transmission-electron-microscopy measurements). The dependence of ${E}_{g}$ on x is anomalous for 0\ensuremath{\le}x\ensuremath{\le}0.2, showing a minimum in the ${E}_{g}$ vs x curve. A simple model (in terms of second-order perturbation theory in s-d and p-d interactions) relates this minimum to a maximum observed in the magnetic susceptibility as a function of x. For samples with x\ensuremath{\gtrsim}0.35, the ${E}_{g}$ dependence on T shows an onset of an additional blue shift as the temperature is lowered below \ensuremath{\sim}150 K. This onset, though not reproduced by our simple calculation, appears to be also related to the presence of s-d and p-d interactions.