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31.
Patrizia Russo Maria Francesca Costabile Christopher James Pettit 《International journal of human-computer interaction》2018,34(1):57-72
Planning Support Systems (PSS) are computer-based tools that assist professionals in land use planning activities. Although several researchers acknowledge the importance of such tools in planning practice, PSS use is limited due to their poor fit to users’ needs and expectations as well as to their low usability. This article presents a study carried out in three different countries, namely, Australia, Italy, and Switzerland, aiming at investigating in-depth the current situation regarding the adoption of PSS and identifying factors preventing their wider use, devoting particular attention to the quality of such systems from the point of view of their users. The study also aimed at analyzing planners’ expectations in order to identify relevant features that PSS should provide. The main part of the study consisted of 35 interviews with planning experts. A follow-up focus group with six further participants was also performed. The results confirmed some findings of previous studies but also revealed new insights. This article provides suggestions on how to address the emerging issues, as well as pathways for creating software that can be adopted and used with satisfaction in the planning practice. 相似文献
32.
N. Mu K. Y. Jung N. M. Yanar G. H. Meier F. S. Pettit G. R. Holcomb 《Oxidation of Metals》2012,78(3-4):221-237
The oxidation behavior of a number of Fe–Cr- and Ni–Cr-based alloys was studied in atmospheres relevant to oxyfuel combustion at 650?°C. Oxidation was greatly enhanced in ferritic model alloys exposed in low p(O2) CO2?+?30%H2O and Ar?+?30%H2O gases. Rapidly growing iron oxides appear to be porous and gas permeable. Transition from non-protective to protective oxidation occurs on alloys with higher Cr contents between 13.5 and 22?wt% in H2O. Excess oxygen, usually found in the actual oxyfuel combustion environments, disrupts the selective oxidation of Fe–Cr alloys by accelerating vaporization of early-formed Cr2O3 in combination with accelerated chromia growth induced by the H2O. Rapid Cr consumption leads to the nucleation and rapid growth of iron oxides. On the contrary, Ni–Cr alloys are less affected by the presence of H2O and excess O2. The difference between Fe–Cr and Ni–Cr alloys is not clear but is postulated to involve less acceleration of chromia growth by water vapor for the latter group of alloys. 相似文献
33.
Pettit Jeremy W.; Roberts Robert E.; Lewinsohn Peter M.; Seeley John R.; Yaroslavsky Ilya 《Canadian Metallurgical Quarterly》2011,25(1):127
Longitudinal trajectories of depressive symptoms, perceived support from family, and perceived support from friends were examined among 816 emerging adults (480 women; 59%). In the context of a larger longitudinal investigation on the predictors and course of depression, data were drawn from eight self-report questionnaire assessments that roughly spanned the third decade of life. An age-based scaling approach was used to model trajectories of depressive symptoms and perceived social support between the ages of 21 and 30. Associative models of the relations between depressive symptoms and perceived social support from family and friends were tested. Results indicated that depressive symptoms decreased and perceived social support increased during the study period. Associative models suggested that among women, higher initial levels of perceived support from family predicted slower decreases in depressive symptoms (b = .34, p 相似文献
34.
Changes in isozymes and peanut protein molecular weights were determined in mature peanuts treated with chitosan and/or Aspergillus flavus. Enzymes involved with the synthesis of phenolic compounds were analyzed. Cinnamyl alcohol dehydrogenase (CAD), glutamate dehydrogenase (GDH), and glucose‐6‐phosphate dehydrogenase (G6PDH) were resolved by native‐PAGE using gradient gels containing 8–25% polyacrylamide while polyphenoloxidases (PPO) were resolved with 10–15% polyacrylamide. Anodic peroxidase (PRX) and shikimate dehydrogenase (SKD) were detected by IEF‐PAGE (pi range of 4.0–6.5). Chitosan induced enzyme activities of PPO (Rf=0.34) and SKD (pl=5.22; pl=4.85) in viable seeds while A. flavus enhanced activities of G6PDH (Rf=0.44), GDH (Rf=0.14), PRX (pl=4.00), PPO (Rf=0.27), and SKD (pl=4.56; pl=4.27). Chitosan + A. flavus promoted GDH (Rf=0.14; Rf=0.20; Rf=0.25) and SKD (pl=4.56; pl=4.04) activities. SKD with five isozyme bands was a better marker for comparing the effects of elicitors. Chitosan and chitosan + A. flavus treated seeds did not have any protein molecular weight changes over 72 h. By 48 h after inoculation of mature seeds with A. flavus, an early change in protein composition of moderately susceptible cultivar of peanuts, Starr, was detected by non‐denaturing gel electrophoresis. Resistant cultivar J‐11 exhibited a delay in alteration of protein composition until 72 h. Manipulation of specific enzyme activities could help elucidate biochemical mechanisms in elicitor‐host interaction and control contamination by aflatoxin‐producing fungi. 相似文献
35.
The uncertainty in gust loads on a rigid, flat-plate airfoil at zero angle-of-attack due to imprecise knowledge of the gust parameters is quantified. The loads are computed using the unsteady vortex lattice model, which includes temporal variations in wake vorticity and the associated downwash on the airfoil. The non-intrusive formulation of the polynomial chaos expansion in terms of the multivariate Hermite polynomials is employed to quantify the uncertainty in the predicted unsteady lift. The expansion coefficients were estimated through Latin hypercube sampling of the parameters in the vertical and streamwise gust spectra. The first-order chaos expansion in terms of the uncertain spectral parameters was found to be sufficient for representing the stochastic aerodynamic lift, which was found to be most sensitive to imprecision in the standard deviation of the vertical component of the gust. These conclusions were found to be unaffected by ignoring the effects of gusts on the locations of the shed vortices in the airfoil’s wake. 相似文献
36.
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38.
MD Moody SC Pettit W Shao L Everitt DD Loeb CA Hutchison R Swanstrom 《Canadian Metallurgical Quarterly》1995,207(2):475-485
Substitution of glycine with glutamic acid at position 48 of the human immunodeficiency virus protease resulted in an enzyme with reduced activity on one of the protease processing sites in the viral Pol polyprotein precursor. Cleavage at this site was restored by a second-site substitution in the substrate replacing an aspartic acid with either glycine or asparagine. These results suggest that the glutamic acid side chain in the mutant protease has an unfavorable charge-charge interaction with this position in the substrate. Cleavage of a processing site in the viral Gag polyprotein precursor with the mutant enzyme was enhanced, and this enhancement was dependent on the presence of an arginine residue in the substrate, again suggesting a charge-charge interaction. The potential for such interactions was confirmed using molecular modeling. The effect of the position 48 substitution was attributed to a 10-fold increase in Km for the processing site in Pol. These results indicate that the addition of a side chain at position 48 can alter the specificity of the HIV-1 protease to substrate in a sequence specific manner and that compensatory changes can be made in the substrate. 相似文献
39.
Deater-Deckard Kirby; Dodge Kenneth A.; Bates John E.; Pettit Gregory S. 《Canadian Metallurgical Quarterly》1996,32(6):1065
The aim of this study was to test whether the relation between physical discipline and child aggression was moderated by ethnic-group status. A sample of 466 European American and 100 African American children from a broad range of socioeconomic levels were followed from kindergarten through 3rd grade. Mothers reported their use of physical discipline in interviews and questionnaires, and mothers, teachers, and peers rated children's externalizing problems annually. The interaction between ethnic status and discipline was significant for teacher- and peer-rated externalizing scores; physical discipline was associated with higher externalizing scores, but only among European American children. These findings provide evidence that the link between physical punishment and child aggression may be culturally specific. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
The laboratories of the U.S. Customs Service frequently encounter the major analytical problem of determining the country
of origin of imported commodities. This is particularly challenging with natural products. This paper will describe the process
for one such commodity —pistachio nuts.
Two approaches were taken, high performance liquid chromatography (HPLC) and Differential Scanning Calorimetry (DSC). It was
found that the results of these two techniques were complimentary and confirmatory. The HPLC data was obtained on the petroleum
ether soluble fraction of the pistachio nuts while the DSC runs evaluated both this fraction and the whole nut. The HPLC results
were further investigated by collecting fractions from the eluting peaks, derivatizing them to form the methyl ester of the
fatty acids, and profiling by gas chromatography to confirm the triglycerides originally present. The U.S. Customs Service
is currently using DSC area ratios to screen imported pistachio nuts for country of origin. 相似文献