Showing papers by "Arizona State University published in 1982"
TL;DR: In this paper, the authors measured the adsorption isotherms in solutions with ionic strengths of 0.01 at 25°C and measured over the arsenite and arsenate concentration range 10−7−10−3 M and the pH range 4−10.
1,154 citations
632 citations
15 Sep 1982
TL;DR: In this paper, it is shown that by taking this overdetermined parametric evaluation approach, a reduction in data-induced model parameter hypersensitivity is obtained, and a corresponding improvement in modeling performance results.
Abstract: In seeking rational models of time series, the concept of approximating second-order statistical relationships (i.e., the Yule-Walker equations) is often explicitly or implicitly invoked. The parameters of the hypothesized rational model are typically selected so that these relationships "best represent" a set of autocorrelation lag estimates computed from time series observations. One of the objectives of this paper will be that of establishing this fundamental approach to the generation of rational models. An examination of many popular contemporary spectral estimation methods reveals that the parameters of a hypothesized rational model are estimated upon using a "minimal" set of Yule-Walker equation evaluations. This results in an undesired parameter hypersensitivity and a subsequent decrease in estimation performance. To counteract this parameter hypersensitivity, the concept of using more than the minimal number of Yule-Walker equation evaluations is herein advocated. It is shown that by taking this overdetermined parametric evaluation approach, a reduction in data-induced model parameter hypersensitivity is obtained, and a corresponding improvement in modeling performance results. Moreover, upon adapting a singular value decomposition representation of an extended-order autocorrelation matrix estimate to this procedure, a desired model order determination method is obtained and a further significant improvement in modeling performance is achieved. This approach makes possible the generation of low-order high-quality rational spectral estimates from short data lengths.
516 citations
TL;DR: In this article, the Raman spectra of crystalline calcium aluminate, anorthite and silica polymorphs are discussed in relation to their crystal structures, and compared with the corresponding glasses.
312 citations
TL;DR: In this paper, the persuasive impact of source credibility was examined in two situations, where a highly credible source was more effective than a moderately credible source when the communication recommended buying a...
Abstract: The persuasive impact of source credibility is examined in two situations. A highly credible source was more effective than a moderately credible source when the communication recommended buying a ...
303 citations
TL;DR: This survey describes all the results known to the authors as of approximately August 1981 and describes the effect on bandwidth of local operations such as refinement and contraction of graphs, bounds on bandwidth in terms of other graph invariants, the bandwidth of special classes of graph, and approximate bandwidth algorithms for graphs and matrices.
Abstract: The bandwidth problem for a graph G is to label its n vertices vi with distinct integers f(vi) so that the quantity max{| f(vi) − f(vi)| : (vi vj) ∈ E(G)} is minimized. The corresponding problem for a real symmetric matrix M is to find a symmetric permutation M' of M so that the quantity max{| i − j| : m'ij ≠ 0} is minimized. This survey describes all the results known to the authors as of approximately August 1981. These results include the effect on bandwidth of local operations such as refinement and contraction of graphs, bounds on bandwidth in terms of other graph invariants, the bandwidth of special classes of graphs, and approximate bandwidth algorithms for graphs and matrices. The survey concludes with a brief discussion of some problems related to bandwidth.
301 citations
273 citations
259 citations
TL;DR: This paper examined the incidence and dynamics of abuse between premarital partners at all levels of commitment and found that abuse typically began after some degree of commitment was established, although the effect of abuse on the relationship was not routinely seen as detrimental.
Abstract: Little research has examined the incidence and dynamics of abuse between premarital partners at all levels of commitment. The present questionnaire study found the incidence of premarital abuse to be substantial and largely reciprocal in nature. Abuse typically began after some degree of commitment was established. Abuse was usually seen as caused by anger, although the effect of abuse on the relationship was not routinely seen as detrimental. It appeared that one possible explanation for abuse in these relationships was that those who stayed in abusive situations reported having fewer alternatives to the violent relationship than those who had terminated an abusive liaison. In general, the respondents had negative attitudes toward violence in relationships. However, those who had experienced abuse were more accepting of violence than those who had not experienced premarital abuse. The discussion focuses on several suggestions for further research to construct a clearer picture of premarital abuse.
251 citations
TL;DR: In this paper, the authors compared the surface temperatures after the eruptions of Tambora (1815), Krakatau (1883), and Agung (1963) and found that the changes in surface temperatures were of similar magnitude, even though the amount of material injected into the stratosphere by these three events differed greatly.
236 citations
TL;DR: In this paper, a structural model for the silica-alumina glass system is proposed, which is consistent with the stable or metastable immiscibility suggested along this join, and the essential features of this model include a modified silica structure at low alumina content, and structure-broken regions at high alumina compositions, with silicon in tetrahedral coordination, but aluminium assuming a variety of bonding geometries.
Abstract: Solar furnace melting and fast-quench techniques have been used to prepare SiO2Al2O3 glasses to high alumina content (near 60 mol% Al2O3), which have been studied by Raman spectroscopy. These spectra may not be simply interpreted. The structures of crystalline compounds in the SiO2Al2O3 system are discussed in relation to their vibrational spectra. On the basis of this discussion and other considerations, a structural model for the silica-alumina glass system is proposed, which is consistent with the stable or metastable immiscibility suggested along this join. The essential features of this model include a modified silica structure at low alumina content, and “structure-broken” regions at high alumina compositions, with silicon in tetrahedral coordination, but aluminium assuming a variety of bonding geometries. These are proposed to include aluminate tetrahedra with higher polymerization than simple corner-sharing, and less well-defined polyhedra of higher average coordination number.
TL;DR: The South African tree Combretumcaffrum has been shown to contain a constituent capable of significantly reversing astrocyte formation employing the National Cancer Institute's 9ASK system.
Abstract: The South African tree Combretumcaffrum has been shown to contain a constituent capable of significantly reversing astrocyte formation employing the National Cancer Institute's 9ASK system. The con...
TL;DR: In this article, the q-Lommel polynomials are shown to be orthogonal with respect to a purely discrete measure with bounded support, which is then used to prove that the prositive zeros of x−νJ(2)v(x; q) are real simple and interlace with the zero of x −ν − 1J( 2)v + 1(x, q), when ν > −1.
TL;DR: Rainbow trout, Salmo gairdneri, were fed pelleted food ad libitum for 35 and 50 days, and visceral lipid contributed most to energy metabolism among the depots investigated, and the U/S ratio rose in viscera and liver and decreased in muscle.
Abstract: Rainbow trout, Salmo gairdneri, were fed pelleted food ad libitum for 35 and 50 days. Lipid deposits were determined in the viscera, liver and muscle (epaxial and hypaxial). Most of the lipid accumulated in the viscera, but the lipid content of liver and epaxial muscle also increased. Hypaxial muscle lipid content remained the same throughout the feeding period. Upon starving the fish for 27 and 48 days following 50 days of feeding, visceral lipid contributed most to energy metabolism among the depots investigated. Muscle also contributed a considerable share while the absolute amount derived from the liver was much smaller.
Patterns of fatty acid mobilization during starvation were also investigated. Saturated acids were preferentially mobilized from the viscera, resulting in a rise in the percentage of monoenes and polyunsaturates. In liver, the percentage of saturates remained relatively constant whereas the percentage of monoenes declined and polyunsaturates increased. In muscle, a substantial increase in saturates was caused by a decline in monoenes; polyunsaturate content remained constant. As a result of these shifts in relative fatty acid composition the U/S (unsaturates to saturates) ratio rose in viscera and liver and decreased in muscle. The UI (unsaturation index) responded in essentially the same way. Possible explanations for preferential fatty acid utilization are discussed in terms of energetics and structural relationships.
TL;DR: An approach to spatial analysis which is more closely tailored to archaeological objectives and archaeological data than are more "traditional" quantitative techniques such as nearest neighbor analysis is discussed.
Abstract: This article discusses an approach to spatial analysis which is more closely tailored to archaeological objectives and archaeological data than are more "traditional" quantitative techniques such as nearest neighbor analysis. Heuristic methods, methods which make use of the problem context and which are guided in part by intuitively derived "rules," are discussed in general and with reference to the problem of spatial analysis in archaeology. A preliminary implementation of such a method is described and applied to artificial settlement data and artifact distributions from the Magdalenian camp of Pincevent. Finally, the prospects for further development of heuristic methods are elaborated. SPATIAL ANALYSIS MAY BE SEEN as a process of searching for theoretically meaningful patterns in spatial data. Of course, this problem has been approached by archaeologists in several ways. The most obvious method of spatial analysis is the visual examination of a point distribution on a map with relevant background information in mind. This intuitive approach has been forsaken (and berated) by many archaeologists with greater aspirations to rigor, in favor of quantitative techniques of spatial analysis, such as nearest neighbor analysis. These techniques generally yield a summary statistic which attempts to characterize the spatial pattern with a single number and perhaps test its significance. The summary statistic is commonly compared from period to period or from area to area. This article reports the progress of an experiment in an alternative approach to the analysis of spatial patterns. This approach, the heuristic approach, is synthetic in that it attempts to open the way for the use of contextual knowledge and human expertise within a formal (computerexecuted) procedure for aiding human-directed spatial analysis. This presentation starts with a brief review of "traditional" quantitative approaches to spatial analysis. It is followed by a discussion of heuristic approaches to problem solving and their application to spatial analysis in archaeology. In the next section, heuristic procedures that have been developed are applied to artificial data sets and then to an analysis of actual data from the Magdalenian camp of Pincevent. The article closes with a discussion of the conclusions of this experiment and prospects for further development.
TL;DR: Incentive theory is extended to account for concurrent chained schedules of reinforcement to demonstrate that incentive theory provides an accurate and integrated account of many of the phenomena of choice.
Abstract: Incentive theory is extended to account for concurrent chained schedules of reinforcement. The basic model consists of additive contributions from the primary and secondary effects of reinforcers, which serve to direct the behavior activated by reinforcement. The activation is proportional to the rate of reinforcement and interacts multiplicatively with the directive effects. The two free parameters are q, the slope of the delay of reinforcement gradient, whose value is constant across many experiments, and b, a bias parameter. The model is shown to provide an excellent description of all results from studies that have varied the terminal-link schedules, and of many of the results from studies that have varied initial-link schedules. The model is extended to diverse modifications of the terminal links, such as varied amount of reinforcement, varied signaling of the terminal-link schedules, and segmentation of the terminal-link schedules. It is demonstrated that incentive theory provides an accurate and integrated account of many of the phenomena of choice.
TL;DR: Computer image-processing techniques may be used to combine three-dimensional representations of the energy relations of pyroclasts moving under the influence of gravity with digital topographic models of volcanoes to generate theoretical hazard maps.
Abstract: Volcanic hazard maps of surge boundaries and deposit thickness can be created by using a simplified eruption model based on an "energy line" concept of pyroclastic surge and flow emplacement. Computer image-processing techniques may be used to combine three-dimensional representations of the energy relations of pyroclasts moving under the influence of gravity (defined by an "energy cone") with digital topographic models of volcanoes to generate theoretical hazard maps. The deposit boundary and thickness calculated for the 18 May 1980 eruption of Mount St. Helens are qualitatively similar to those actually observed.
TL;DR: More than 60% of single respondents reported having experienced abusive or aggressive behaviors or having inflicted them during courtship as discussed by the authors, and a hypothesized relationship between social class and violence in courtship was not supported, however.
Abstract: Challenging Gelles’ (1972) assertion that violence between intimates is likely to occur only within a family context, more than 60% of a sample of 371 single respondents reported having experienced abusive or aggressive behaviors or having inflicted them during courtship. Theoretical considerations and empirical consistencies derived from the marital violence literature supported hypothesized relationships between more serious courting relationships and violence and between experienced childhood violence and the occurrence of violence in courtship. A hypothesized relationship between social class and violence in courtship was not supported, however. A conflict theory framework and propositions extracted from choice and exchange theory explain these findings. The extent of courtship violence documented here is in all probability an underestimate of its actual occurrence.
TL;DR: In this article, the enthalpies of solution in molten 2PbO · B 2 O 3 at 985 K were reported for series of glasses xCa 0.5 AlO 2 -(1− x ) SiO 2 (O ≤ x ≤ 0.99) and xNaAlO 2 −(1 − x )SiO 2 0.4 (0 ≤ x ≥ 0.56).
TL;DR: In this article, the concept of generation and recombination lifetimes is discussed and the regimes of device operation where they apply are discussed and it is shown experimentally for the first time that the two can be very different in magnitude.
Abstract: The purpose of this brief is to discuss the concept of generation and recombination lifetimes, a concept frequently confused in the literature. The regimes of device operation where they apply is discussed and it is shown experimentally for the first time that the two can be very different in magnitude.
TL;DR: Evidence is presented supporting the conclusion that the GN contributes relatively little to fundamental taste reactivity, but is deeply involved in cognitive (learning and memorial) taste processes; that is, “reactive salience" to taste stimuli is preserved following GN ablation, while “associative salience” is markedly degraded.
Abstract: Research findings related to the functional significance of the gustatory neocortical system of the rat are reviewed and interpreted. Studies of gustatory neocortex (GN) involvement in taste-related cognitive processes are emphasized after briefly reviewing GN anatomy and physiology. Evidence is presented supporting the conclusion that the GN contributes relatively little to fundamental taste reactivity, but is deeply involved in cognitive (learning and memorial) taste processes; that is, “reactive salience” to taste stimuli is preserved following GN ablation, while “associative salience” is markedly degraded. Apparent functional similarities between GN and other sensory neocortical areas are emphasized throughout the paper, and a hierarchical view of gustatory system functioning is addressed.
TL;DR: Carbynes have recently attracted attention as possible interstellar dust constituents and as carriers of presolar noble gases in meteorites, and their existence and that of the related mineral chaoite are questioned.
Abstract: Almost 15 years have passed since carbynes entered the literature as new forms of elemental carbon. They recently attracted attention as possible interstellar dust constituents and as carriers of presolar noble gases in meteorites. Their existence and that of the related mineral chaoite are questioned, and a reevaluation of previous data is suggested.
TL;DR: In this article, the diurnal variation of the differences in the brightness temperatures between each of the four surface-sensing IRTM (infrared thermal mapper) wavelength bands is used to separate the average grain size determined by the thermal inertia into the surface block population and the inertia of the fine component.
Abstract: The goal of the study presented here is to use the diurnal variation of the differences in the brightness temperatures between each of the four surface-sensing IRTM (infrared thermal mapper) wavelength bands to separate the average grain size determined by the thermal inertia into the surface block population and the inertia of the fine component. It is noted that the thermal emissivity of the surface can also be determined and that this in turn can be used to estimate compositional variations. What is more, the atmospheric dust content can be estimated and used to infer sources and sinks of airborne dust. Owing to the number of unknowns, observations at more than one time of day are necessary to determine each of these parameters independently. The data discussed here were obtained by the IRTM, which had five thermal channels centered at 7, 9, 11, 15, and 20 microns and one channel that measured solar reflectance for from 0.3 to 3.0 microns.
TL;DR: In this article, the authors pointed out that characteristic styles of degradation and modification of obvious Martian basins make it possible to recognize more subtle expressions and reveal the long-lasting influence of basin formation on the crust of Mars.
Abstract: It is pointed out that characteristic styles of degradation and modification of obvious Martian basins make it possible to recognize more subtle expressions. This approach is seen as providing not only additional basins to the existing inventory but also fundamental clues for initial impact basin structure and stratigraphy. It also reveals the long-lasting influence of basin formation on the crust of Mars in spite of extensive erosion and resurfacing. Consideration is given to five clear examples of modified impact basins, and regions around each that have undergone similar processes (fracturing, collapse, channeling) are delineated. These processes among the different basins are then compared, and similar zones of modification are correlated with concentric basin rings. Consideration is then given to the implications of these observations for current models of basin formation and to the role of impact basins in controlling regional tectonics. The results indicate that large multiring impact scars leave a major but sometimes subtle imprint on the geologic structure of stable crustal regions on Mars.
TL;DR: Topaz rhyolites are fluorine-rich alkaline silicic lavas and shallow intrusives that are characterized by the presence of topaz (Al 2 SiO 4 F 2 ) in gas cavities, commonly associated with Mn-Fe garnet, bixbyite, pseudobrookite, specularite, quartz, and other minerals as mentioned in this paper.
Abstract: Topaz rhyolites are fluorine-rich alkaline silicic lavas and shallow intrusives that are characterized by the presence of topaz (Al 2 SiO 4 F 2 ) in gas cavities, commonly associated with Mn-Fe garnet, bixbyite, pseudobrookite, specularite, quartz, and other minerals. In the western United States, Cenozoic (0.5-50 m.y. old for dated examples) topaz rhyolites occur on both sides of the Colorado Plateau (in Colorado, New Mexico, Arizona, Utah, and Nevada) and in Idaho and Montana. They also occur in a single linear belt in Mexico. Their enrichment in lithophile (fluorophile) elements (Li, Rb, Cs, U, Th, Nb, Ta, Sn, W, Be, etc.) leads to the term rare metal rhyolites. Similar F-rich rocks from Mongolia and the Soviet Union have been called ongonites. Topaz rhyolites appear to represent a special class of the bimodal or high silica rhyolites of the western United States.Their extensional tectonic setting and geochemical characteristics suggest that topaz rhyolites are the extrusive equivalents of anorogenic or residual (A- or R-type) granites. Their petrogenesis presumably involves partial melting of Precambrian continental crust (they appear to be restricted to areas of such crust) in the presence of a high heat flow (which tends to enrich F in solids at the expense of H 2 O). Mafic magmas may provide the heat for melting. Further differentiation may depend on (1) zone refining during ascent, (2) extreme fractional crystallization, (3) dehydration due to early pyroclastic volcanism, and (4) apical enrichment of near-surface magma chambers due to liquid state processes.Practical interest in topaz rhyolites results, in part, from the spatial and genetic association with volcanogenic deposits of Be, U, Sn, and F. Spor Mountain, Utah, provides the best example of this type of mineralization. Topaz rhyolite lavas from productive districts tend to be relatively phenocryst rich, poor in miarolitic cavities, and granophyrically crystallized. Vitrophyres, where present, are exceptionally rich in F and fluorophile elements, and rare earth patterns are exceptionally fiat (low La/Yb ratios) and have pronounced negative Eu anomalies. Near-surface country rocks penetrated by the volcanic vents were reactive (carbonate rocks) and water tables were presumably high.Most topaz rhyolite lavas are not associated wth volcanogenic mineralization. These nonproductive lavas are generally phenocryst poor, distinctly flow banded, lithophysa rich, and spherulitically-crystallized. Vitrophyres are less enriched in F and fluorophile elements, country rocks are nonreactive, and water tables could have been low.Topaz rhyolites of both the productive and nonproductive type may be valuable indicators of subsurface mineralization. Their distribution coincides very closely with that of (1) fluorite and silver-base metal districts, (2) the central and eastern tungsten belts of Kerr (1946), and (3) topaz-rich porphyry Mo-W deposits of the Climax and Henderson type. Topaz rhyolite volcanic vent areas might then reflect the existence of large F-rich magma chambers below with (1) subvolcanic breccia, porphyry, and greisen vein deposits of Mo, W, Sn, and other elements, (2) base and precious metal veins and fluorite-rich replacements, and (3) more deeply seated rare metal pegmatites.
TL;DR: In this paper, a brief description of the experiments performed to obtain data on windblown particles and abrasion of rocks in a simulated Martian environment is given, and preliminary results are presented and combined with Viking meteorological data in estimating rates of wind-abrasion at the VL-1 site on Mars.
Abstract: A brief description is given of the experiments performed to obtain data on windblown particles and abrasion of rocks in a simulated Martian environment. Preliminary results are presented and combined with Viking meteorological data in estimating rates of wind abrasion at the VL-1 site on Mars. Attention is also given to the implications that the results have for Martian surface history. Calculations of the present rates of abrasion by windblown particles on Mars yield values ranging from 0.021 cm/yr to nearly zero, depending on the target, the agent of abrasion, and the availability of windblown particles.
TL;DR: In this paper, the authors summarized the findings from surveys of faculty and students on academic dishonesty conducted at an American university and found that over 56% of the students admitted to cheating but methods of prevention or detection are not adequate as only 3% were caught.
Abstract: This paper summarizes the findings from surveys of faculty and students on academic dishonesty conducted at an American university. Two separate surveys administered to a sample of 364 engineering students and 80 faculty indicated the attitudes and occurrences of cheating. While 62% of the students admitted to copying homework or laboratory reports, only 51% of the faculty considered this cheating. Students (38%) and faculty (86%) believe “second-time” cheaters should be expelled from the university. Of students, 68% believe competition for grades is the major reason for cheating. Over 56% of the students admitted to cheating but methods of prevention or detection are not adequate as only 3% were caught. Monitoring during exams is a deterrent to cheating according to almost half the students. Surveys of students and faculty and a quiz for faculty on cheating have increased awareness about students' cheating and reduced its incidence.
TL;DR: In this article, the authors presented alternating current electrical conductivity (σ) data for AgIAl2O3, AgI-SiO2 and fly ash, as a function of composition, temperature, and frequency.
TL;DR: In this paper, the authors derived the viscosity of the lower mantle by making comparisons of the observed secular motions of the earth's rotation axis with theoretical results from a layered viscoelastic, rotating earth, which has been subjected to glacial forcing.
Abstract: Until recently most estimates of the deep mantle viscosity were based on analyses of postglacial uplifts, and there were no serious estimates of the sensitivity of the derived viscosity solutions to variations of the input parameters, such as those associated with the surface loading. In this paper the viscosity of the lower mantle is arrived at by making comparisons of the observed secular motions of the earth's rotation axis with theoretical results from a layered viscoelastic, rotating earth, which has been subjected to glacial forcing. Our model, consisting of an elastic lithosphere, a two-layer, adiabatically stratified viscoelastic mantle, and an inviscid core, is essentially analytical, and this makes it economically feasible to use as an aid in conducting an extensive sensitivity analysis of the lower mantle viscosity from changes in the parameters connected with the deglaciation phenomenon. Both sets of rotational data, polar wander and nontidal deceleration of the length of the day, have been employed to constrain the viscosity structure. On the basis of this type of investigation, the viscosity of the lower mantle is found invariably to be larger than that of the upper mantle and lies between 1 and 4×1022 P. Our results, which just rely on the second degree harmonic of the strain field, also lead to a determination of an upper bound to the thickness of the globally averaged lithosphere. This value, ranging between 130 and 190 km, suggests that strong lateral heterogeneities between oceanic and continental plates may extend a few hundred kilometers into the upper mantle.
TL;DR: In this article, the authors argue that in most cases involving only one potential defendant, the conventional interpretation of the preponderance standard is appropriate, but they note an important exception.
Abstract: The preponderance-of-the-evidence standard usually is understood to mean that the plaintiff must show that the probability that the defendant is in fact liable exceeds 1/2. Several commentators and at least one court have suggested that in some situations it may be preferable to make each defendant pay plaintiff's damages discounted by the probability that the defendant in question is in fact liable. This article analyzes these and other decision rules from the standpoint of statistical decision theory. It argues that in most cases involving only one potential defendant, the conventional interpretation of the preponderance standard is appropriate, but it notes an important exception. The article also considers cases involving many defendants, only one of whom could have caused the injury to plaintiff. It argues that ordinarily the single defendant most likely to have been responsible should be liable for all the damages, even when the probability associated with this defendant is less than 1/2. At the same time, it identifies certain multiple-defendant cases in which the rule that weights each defendant's damages by the probability of that defendant's liability should apply.