Showing papers by "University of Delaware published in 1979"
TL;DR: For example, this article found that stressed individuals feel significantly better after exposure to nature scenes rather than to American urban scenes lacking nature elements, and that the salient effect of the nature exposures was to increase positive affect, including feelings of affection friendliness, playfulness, and elation.
Abstract: Summary and Discussion The findings suggest that stressed individuals feel significantly better after exposure to nature scenes rather than to American urban scenes lacking nature elements. Compared to the influences of the urban scenes, the salient effect of the nature exposures was to increase Positive Affect — including feelings of affection friendliness, playfulness, and elation. The increase in positive affect produced by the nature scenes is consistent with the finding that the nature exposures also significantly reduced Fear Arousal. According to psychological theories, a reduction in arousal or activation produces pleasurable feelings if an individual is experiencing stress or excessive arousal (Berlyne, 1971, pp. 81–82). In contrast to the nature scenes, the urban views tended to work against emotional well‐being. The major effect of the urban scenes was to significantly increase Sadness. There was also a consistent but non‐significant tendency for the urban scenes to‐aggravate feelings of Anger/...
687 citations
TL;DR: In this paper, the authors used the quasi-static Mononobe-Okabe analysis for the prediction of earthquake dynamic forces on a gravity retaining wall, and showed that wall inertia effects are of the same order as the dynamic soil thrust.
Abstract: First, the paper shows that in order to use the quasi-static Mononobe-Okabe analysis for the prediction of earthquake dynamic forces on a gravity retaining wall, wall inertia effects must be included. Second, a design procedure is developed in which the designer chooses an acceptable level of wall displacement: he then computes the design wall weight which will restrict displacement in an earthquake to the predetermined level. Wall inertia effects are shown to be of the same order as the dynamic soil thrust, and to be sensitive to vertical acceleration and to base and wall friction. Design recommendations are given which relate to proposed American provisions for seismic zoning.
324 citations
TL;DR: SSS scores were found to be elevated in persons reporting a history of manic-depressive or sociopathic spectrum (including alcoholism and drug abuse) disorder, but were not related to general psychopathology, unipolar depression, schizophrenia, or neurosis.
Abstract: A sample of 2,115 persons responded to an article in a popular magazine by taking the Sensation Seeking Scale (SSS) and supplying personal information by mail, including data about past treatment, hospitalization, and diagnosis of psychiatric disorders. Subjects falling into certain diagnostic categories were closely matched with controls from the same sample who reported no history, treatment, or diagnosis of disorder. SSS scores were not related to general psychopathology, unipolar depression, schizophrenia, or neurosis, but were found to be elevated in persons reporting a history of manic-depressive or sociopathic spectrum (including alcoholism and drug abuse) disorder.
292 citations
TL;DR: Four experiments show that in a VM paradigm sequential presentation of the display leads to increases in accuracy and decreases in latency, taken as confirming evidence for the proposed two-stage visual search model.
Abstract: A two-stage visual search model is described. Four experiments show that in a VM paradigm sequential presentation of the display leads to increases in accuracy and decreases in latency. Slower presentation rates allow for faster transfer of the target from iconic to short-term memory. When target and background items are dissimilar, transfer to short-term memory need not take place and decisions can be made on the basis of the Stage 1 analysis. These results are taken as confirming evidence for the proposed model.
238 citations
TL;DR: In this article, a macroscopic model for predicting the strength of composite laminate containing a circular notch is introduced, which quantifies the reduction in strength of a given composite material or laminate due to the circular notch.
Abstract: A macroscopic model for predicting the strength of a composite laminate containing a circular notch is introduced A property, which quantifies the reduction in strength of a given composite material or laminate due to a circular notch, is proposed The superposition of notched strength data for several important composite material systems and laminate stacking sequences is achieved through development of a notched strength-radius superposition method and the definition of radius shift parameters, ac and am The superposition allows prediction of the in fluence of laminate stacking sequence upon notched strength In addition, data for composite material systems or laminates of common stress concen tration factor is shown to superimpose by use of the developed shift parameters
209 citations
01 Jan 1979
TL;DR: Zuckerman has pursued the conceptualization and measurement of sensation seeking with such success that it is beginning to take its place alongside such long-established concepts as introversion and extraversion as discussed by the authors.
Abstract: Zuckerman has pursued the conceptualization and measurement of sensation seeking with such success that it is beginning to take its place alongside such long-established concepts as introversion and extraversion. Zuckerman conceives sensation seeking as a motive that can be measured as both trait and state.
200 citations
TL;DR: In this paper, the effect of substrate critical surface tension on the rate of microbiological attachment to solid surfaces immersed in natural seawater is considered and a model based on interfacial tension and the work of Good and co-workers is presented which accounts for the presence of both types of behavior.
196 citations
182 citations
TL;DR: In this paper, the projected gasoline to mid-distillate ratio through the year 2000 and beyond is given, where the shift is away from high octane fuels requiring a relatively high aromatics content and a relatively low hydrogen content to highly paraffin-based fuels having a high hydrogen content.
Abstract: During the last decade there has been increased interest in the production of synthetic fuels and chemicals feedstocks from coal and oil shale due to declining petroleum reserves. Table 1 gives the projected gasoline to mid-distillate ratio through the year 2000 and beyond; the shift is away from high-octane fuels requiring a relatively high aromatics content and a relatively low hydrogen content to highly paraffin-based fuels having a high hydrogen content. Figure 1 shows the projected United States energy supply and demand through the year 1990 [2], Current petroleum production in the contiguous United States is about 9 million bbl/day and has declined at a rate of about 0.5 million bbl/day per year for a number of years. Alaskan oil will arrest this decline in production briefly but will not make up for even the loss in the rate of petroleum production incurred in the contiguous 48 states during the last 5 years. In all probability, declining production from current oil fields will not be offs...
181 citations
TL;DR: In this article, a unified shell-model description of nuclear deformation valid throughout the periodic table is presented, and it is shown that deformation is produced by the isoscalar component of the neutron-proton interaction in this region, as in the lighter ($2s,$1d$)-shell region.
Abstract: A unified shell-model description of nuclear deformation valid throughout the periodic table is presented. Microscopic calculations for the Zr and Mo isotopes are carried out in the frameworks of the shell model and the Hartree-Fock-Bogoliubov method, respectively, to study the shape transition in these nuclei. It is shown that deformation is produced by the isoscalar component of the neutron-proton ($n\ensuremath{-}p$) interaction in this region, as in the lighter ($2s$,$1d$)-shell region. Deformation sets in when the $T=0$ $n\ensuremath{-}p$ interaction dominates over the sphericity-favoring pairing interaction between $T=1$ pairs of nucleons. When shell effects are important, as for the light and medium-weight regions mentioned above, the simultaneous occupation of neutrons and protons of spin-orbit "partner" orbitals plays a crucial role in determining the onset of deformation. However, their effect is probably less important in the rare-earth and transuranic regions due to the rapid accumulation of single-particle orbitals.NUCLEAR STRUCTURE Microscopic description of nuclear deformation; shell-model calculations of $^{96}\mathrm{Zr}$, $^{98}\mathrm{Zr}$, and $^{100}\mathrm{Zr}$; HFB calculations of $^{98}\mathrm{Mo}$-$^{110}\mathrm{Mo}$; discussion of light and heavy deformed nuclei; relation to interacting boson approximation.
177 citations
TL;DR: In this article, the results of white-cap coverages of the ocean surface obtained by previous investigators in both the Atlantic Ocean and the Pacific Ocean are reanalyzed and the variation of coverage with wind velocity appears to be related to the rate of energy supplied by the wind.
Abstract: Results of white-cap coverages of the ocean surface obtained by previous investigators in both the Atlantic Ocean and the Pacific Ocean are reanalyzed. The variation of coverage with wind velocity appears to be related to the rate of energy supplied by the wind. The coverage is also found to vary with stability conditions of the atmospheric surface layer. Empirical formulas are deduced for various sea states and stability conditions, and application of these formulas to remote sensing of marine wind velocity is discussed.
TL;DR: In this article, the plane boundary value problem for the Laplacian with Dirichlet data on one part and Neumann data on the remaining part of the boundary is converted into a system of Fredholm integral equations.
Abstract: Although the plane boundary value problem for the Laplacian with given Dirichlet data on one part Γ2 and given Neumann data on the remaining part Γ2 of the boundary is the simplest case of mixed boundary value problems, we present several applications in classical mathematical physics. Using Green's formula the problem is converted into a system of Fredholm integral equations for the yet unknown values of the solution u on Γ2 and the also desired values of the normal derivatie on Γ1. One of these equations has principal part of the second kind, whereas that one of the other is of the first kind. Since any improvement of constructive methods requires higher regularity of u but, on the other hand, grad u possesses singularities at the collision points Γ1 ∩ Γ2 even for C∞ data, u is decomposed into special singular terms and a regular rest. This is incorporated into the integral equations and the modified system is solved in appropriate Sobolev spaces. The solution of the system requires to solve a Fredholm equation of the first kind on the arc Γ2 providing an improvement of regularity for the smooth part of u. Since the integral equations form a strongly elliptic system of pseudodifferential operators, the Galerkin procedure converges. Using regular finite element functions on Γ1 and Γ2 augmented by the special singular functions we obtain optimal order of asymptotic convergence in the norm corresponding to the energy norm of u and also superconvergence as well as high orders in smoother norms if the given data are smooth (and not the solution).
TL;DR: Diets containing both I. galbana and T. pseudonana invariably supported greater growth than diets consisting solely of either species, indicating synergism in the relative food values of the species.
TL;DR: In this article, the adsorption characteristics of Cu(II) in the presence of chelating agents was investigated in the laboratory, and the results showed that the addition of Chelating Agents improved the extent of the adaption, although ligand:Cu(II)-NTA-γ-Al2O3 system.
TL;DR: Gel filtration, NaDodSO, gel electrophoresis, and amino acid analysis suggest that the enzyme is a tetramer, comprised of subunits of about 42 000 molecular weight, containing 3-4 molecules Mammalian fatty acyl-CoA dehydrogenases are flavo- proteins participating in the first dehydrogenation step of fatty acid oxidation.
Abstract: Comparatively large amounts of an acyl-CoA dehydrogenase have been obtained from pig kidney by a procedure which does not involve prior isolation of mito- chondria. The pattern of substrate specificity and the extent of substrate-induced bleaching of the flavin chromophore, using butyryl-, octanoyl-, and palmitoyl-CoA, suggest that the enzyme be classified as a general acyl-CoA dehydrogenase. The purified flavoprotein exhibits absorbance ratios at 272, 373, and 446 nm of 5.7:0.65:1.0, respectively, with an ex- tinction coefficient for bound flavin adenine dinucleotide (FAD) of 15.4 mM-' cm-' at 446 nm. Gel filtration, NaDodSO, gel electrophoresis, and amino acid analysis in- dicate that the enzyme is a tetramer, comprised of subunits of about 42 000 molecular weight, containing 3-4 molecules Mammalian fatty acyl-CoA dehydrogenases are flavo- proteins participating in the first dehydrogenation step of fatty acid @-oxidation which leads to the formation of a,@-unsat- urated acyl-CoA derivatives (Beinert, 1963). The reducing equivalents are then passed to a second component, electron transfer flavoprotein (ETF;' Crane et al., 1956), which in- teracts with the respiratory chain, possibly at the level of a
TL;DR: In this article, a large variety of barites collected from marine and continental environments was analyzed by neutron activation for the rare earth elements (REE) La, Ce, Sm, Eu and Dy.
TL;DR: In this article, the formation of supported molybdate catalysts was investigated using laser Raman spectroscopy, and the effect of variations in the preparation procedure was investigated.
TL;DR: The high productivity of this resident fish population indicates that F. heteroclitus makes an important contribution to the energy transfers within tidal marshes, and is summarized in a model of changes in age and size class structure over an annual cycle.
TL;DR: Four species of bivalve molluscs were fed diets consisting of varying proportions of the yeast Candida utilis and the diatom Thalassiosira pseudonana and growth of soft tissue in Crassostrea virginica decreased with the amount of yeast in the diet.
TL;DR: The maximum number of new neutrinos with superweakly interacting, light (ensuremath{\lesssim} MeV) particles is between 1 and 20 in the universe as mentioned in this paper.
Abstract: Previous work has used the primordial abundance of $^{4}\mathrm{He}$ to infer limits on the number of neutrinos with full-strength neutral-current weak interactions. By accounting for the quark-gluon constituents of hadrons, we extend the analysis to earlier times and higher temperatures and densities and, therefore, to considerably weaker interactions. The maximum number of new, superweakly interacting, light (\ensuremath{\lesssim} MeV) particles is between \ensuremath{\sim}1 and \ensuremath{\sim}20.
TL;DR: In this paper, a thin film photovoltaic cell of CdS/Cu 2 S was designed and fabricated to achieve high energy conversion efficiency of 14-15% using a (CdZn)S/cu 2 S junction.
TL;DR: Photopic contrast thresholds to sinusoidal gratings were measured in five goldfish by conditioning respiration in a Pavlovian paradigm, finding the limit of full summation previously found for the light-adapted goldfish.
TL;DR: In this paper, the conformation of polymer molecules or of micelles is known to change when a stress or deformation-rate field is applied to a fluid, and the resulting entropy changes must lead to diffusion of the species effected toward regions of minimum stress level in any system in which the stress varies with position.
Abstract: The conformation of polymer molecules or of micelles is known to be changed when a stress or deformation-rate field is applied to a fluid. Thermo dynamic considerations suggest that the resulting entropy changes must lead to diffusion of the species effected toward regions of minimum stress level in any system in which the stress varies with position. That is to say, spatial stress gradients inevitably appear to give rise to spatial concentration gradients. Such flows differ intrinsically, therefore, from homogeneous flows in which the stress field, hence the fluid concentration levels and properties, are uniform throughout the continuum. Preliminary measurements of these concentration fields are reported and consequences of this phenomenon in several flow processes are considered.
TL;DR: In this article, a semi-infinite transversely isotropic medium with the plane boundary parallel to the plane of isotropy is solved by using the potential function method, where the Green's function solutions are expressed in terms of harmonic and bi-harmonic functions which are obtained by the separation of variables method.
TL;DR: Host plants and animals and the parasite species which attack them have recently been shown to conform to the species-area relation consistent with the theory of island biogeography, and it is suggested that parasite species richness asymptotically approaches an upper limit established mainly by host "island" size.
Abstract: Host plants and animals and the parasite species which attack them have recently been shown to conform to the species-area relation consistent with the theory of island biogeography (Dritschilo et al., 1975; Opler, 1974; Seifert, 1975; Strong, 1974a, b; Strong and Levin, 1975; Strong et al., 1977; Tepedino and Stanton, 1976). This pattern, supplemented by additional statistical analysis in some examples (Dritschilo et al., 1975; Strong, 1974q, b; Strong et al., 1977) has suggested that parasite species richness asymptotically approaches an upper limit established mainly by host "island" size and that recent evolutionary age has an insignificant effect on the number of species which attack the host. Although a logarithmic fit to the species-area relation cannot be taken as a confirmation of the equilibrium theory per se (Lynch and Johnson, 1974; Simberloff, 1974, 1976), and although there are some minor statistical deficiencies in the data presentation (Haas, 1975; Kuris and Blaustein, 1977), this relation is a robust empirical generalization with wide application. Host island studies have been of two types based on what is defined as an island and the time scale involved in approach to the asymptote. In one type, each individual host or a small patch of hosts is taken as an island with the species pool being all of those species known to attack that host in that part of its range (Brown and Kodric-Brown, 1977; Price, 1976; Seifert, 1975; Simberloff, 1976a; Strong, 1974b, 1976; Strong et al., 1977; Tepedino and Stanton, 1976; Ward and Lakhani, 1977). Area effects are due to the size of individual hosts or host patches, and distance effects are due to the distance between hosts or patches. All species on an individual host or patch for a given sampling episode must be assessed; and if equilibrium is established, turnover would occur in ecological time. Often, particularly in areas with high seasonality, the condition of the host changes through time, and an asymptote is never reached before the end of the season, for example in cushion plants in Wyoming (Tepedino and Stanton, 1976), in soybeans in Illinois (Price, 1976), and in small salt marsh islands in Florida (Rey and McCoy, pers. comm.).
TL;DR: In this article, the shape transition in the Zr isotopes is investigated in the framework of the Shell Model, and the neutron-proton interaction between selected orbitals is found to be instrumental for the onset of deformation in this neutron-rich region.
TL;DR: In this paper, the concept of activity parameter as an internal state variable is introduced as an yardstick for the degree of swelling and the rate of evolution of this has been related directly to relaxation time.
TL;DR: For every viscoelastic fluid studied in the contraction geometry, it was found that increasing the flow rate beyond a certain limit resulted in disturbance to the stable entry flow patterns described in Parts I and II as discussed by the authors.
Abstract: For every viscoelastic fluid studied in the contraction geometry, it was found that increasing the flow rate beyond a certain limit resulted in disturbance to the stable entry flow patterns described in Parts I and II. An examination of the development of the entry flow disturbances was carried out using still and cine photography. Still photographs are presented to illustrate the characteristics of the unstable flow patterns. The time varying nature of the flow has been recorded on a cine film Flow Patterns in Abrupt Entry Flow of Viscoelastic Fluids which is available for loan. Critical condition criteria for the onset of the periodic flow disturbances were obtained in terms of the fundamental fluid properties and are presented and compared with other suggested criteria for the onset of unstable entry flow of viscoelastic fluids.
Patent•
29 May 1979TL;DR: In this article, the authors proposed a technique for manufacturing durable, reliable solar cells by a continuous process suitable for large-scale manufacture, in substance, providing a reel of thin metal foil substrate and forming on the substrate a series of layers operative to form a photovoltaic junction, short prevention blocking layers, contacts and integral encapsulation.
Abstract: A technique for manufacturing durable, reliable solar cells by a continuous process suitable for large-scale manufacture involves, in substance, providing a reel of thin metal foil substrate and forming on the substrate a series of layers operative to form a photovoltaic junction, short prevention blocking layers, contacts and integral encapsulation. The foil substrate is processed as a continuous reel substantially until final testing at which point, if desired, it can be cut into individual cells for deployment. In comparison with a batch process, the continuous technique can reduce manufacturing cost by as much as a factor of two.