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1.
A study was conducted from 1978 to late 1984 of the survival of inner-city street trees planted by the Oakland, California urban forestry program. The tree survival rate of approximately 60 to 70 percent from the trees planted in neighborhood parkways through urban forestry sponsored block parties contrasted sharply with less than one percent survival of trees planted earlier by the Model Cities program without community participation or ceremonial plantings. Explanations for the high tree survival were tested using participant observation, interviews with residents, and a small panel. Tree survival was not found to be related to the explanations provided by urban forestry ideology; namely, that residents had been educated to hold both instrumental and expressive values toward trees. Rather, the explanation appeared to be the function of an unintended solution to the issue of parkway ownership. The tree planting process which included species selection meetings and tree planting ceremonies tended to define the parkway trees as a resident's property, thus decreasing the significance of the parkway-property barrier. The generality of the Oakland illustration is discussed.  相似文献   
2.
The distribution of fracture intensities occurring during compression of puffed corn meal extrudates was described using an exponential function, and parameters from that analysis were used as fracturability indices. Since “jagged” or oscillating stress-strain functions are typical for porous and brittle materials, fracture intensities were determined by measuring the abrupt, sequential reductions in stress produced during compression. Both distribution exponent and cumulative fracture stress correlated strongly with fracturability measured by other techniques, including fractal and Fourier analysis of stress-strain functions. Distribution parameters also indicated textural differences due to process parameters (structural modification through addition of different levels of sucrose) and storage conditions (equilibration at various relative humidities).  相似文献   
3.
ABSTRACT: This study on the development of citizen participation in Israel is based on the findings of a case study of Israel's Project Renewal, a comprehensive community renewal and development program which resembles Urban Renewal, Model Cities, and the War on Poverty programs in the US. The author reviews the characteristics of the Israeli political system which traditionally have denied a meaningful role for citizen participation. He compares the practice with the intent of Project Renewal to foster the participation of neighborhood residents. Finally, he comments on the unique v. the universal character of the Israeli experience with citizen participation: Will Israel follow the US pattern of increased citizen participation in community development programs?  相似文献   
4.
As a first step toward understanding how noctuid moths evolve species-specific pheromone communication systems, we hybridized and backcrossed two closely related moth species, Heliothis virescens (Hv) and H. subflexa (Hs), which differ qualitatively and quantitatively in their multi-component sex pheromone blends. We used amplified fragment length polymorphism (AFLP) marker-based mapping of backcross families to determine which of the 30 autosomes in these moths contained quantitative trait loci (QTL) controlling the percentages of specific chemical components in the pheromone blends. In two previous backcrosses to Hs, we found a strong depressive effect of Hv-chromosome 22 on the percentage of three acetate components in the pheromone gland. These acetates are present in Hs and absent in Hv. Here, we describe how we introgressed Hv-chromosome 22 into the genomic background of Hs. Selection for Hv-chromosome 22 started from backcross 3 (BC3) females. All females that had Hv-chromosome 22 and a low percentage of acetates (< 3% of the total amount of pheromone components present) were backcrossed to Hs males. In BC5 to BC8, we determined whether Hv-chromosome 22 was present by a) running only the primer pairs that would yield the markers for that chromosome, and/or b) determining the relative percentages of acetates in the pheromone glands. Either or both genotype and phenotype were used as a criterion to continue to backcross these females to Hs males. In BC9, we confirmed the isolation of Hv-chromosome 22 in the Hs genomic background, and backcrossed the males to Hs females to eliminate the Hv-sex chromosome as well as mitochondrial DNA. The pheromone composition was determined in BC3, BC5, and BC11 females with and without Hv-chromosome 22. All backcross females with Hv-chromosome 22 contained significantly less acetates than females without this chromosome. In addition, BC3 females with Hv-chromosome 22 contained significantly more Z11-16:OH than BC3 females without Hv-chromosome 22. However, in BC5 and BC11 females, the correlation between Z11-16:OH and Hv-chromosome 22 was lost, suggesting that there are separate QTL for the acetates and for Z11-16:OH, and that the relative amount of the alcohol component is only affected in epistasis with other (minor) QTL. Now that we have succeeded in isolating the chromosome that has a major effect on acetate production, we can test in behavioral experiments whether the presence of acetates may have been a driving force for a shift in pheromone composition. Such tests are necessary to move towards an evolutionary understanding of the differentiation in sexual communication in Heliothis spp. moths.  相似文献   
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ACCR导线是种新型导线,它看上去与传统的ACSR基本相同,但它是由合成材料和耐热铝合金组成.它的主要特点是高强度、重量轻(钢芯的1/3),良好的传导性能(钢芯的3倍)以及热膨胀系数低(钢芯的1/2),因此可以在低弛度重量大线段替代钢导线.美国在2个不同地点对这种新型导线进行现场试验,以验证其各种性能.  相似文献   
7.
In our experiments with the pulsed Oribtron MASER, we have noted that there is an upward chirp in frequency even though the anode voltage is decreasing. We have found theoretically that this is a natural consequence of the negative-mass instability and the chirp rate can be predicted from this theory. Experimental data we have obtained is also in good agreement with these predictions.  相似文献   
8.
FRED COHEN 《EDPACS》2013,47(6):17-23
Abstract

Auditing Software Development: A Manual With Case Studies, by S. Rao Vallabhaneni. John Wiley and Sons (605 Third Avenue, New York, 10158-0012), 1990, 439 pp. Includes a glossary and bibliography. Price: $75.00, plus shipping and handling charges.

Computer Crime: Techniques For Preventing And Detecting Crime In Financial Institutions, by Gregory Wold and Robert Shriver. Bankers Publishing (60 Gould Center, Rolling Meadows IL 60008), 1989, 255 pp. Includes a glossary. Price: $49, with a discount for BAI members.  相似文献   
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Fuzzy logic controllers have been used increasingly in industrial applications. We introduce the probabilistic controller as an alternative to fuzzy logic controllers. The probabilistic controller is a 'universal' controller with a structure closely analogous to a popular type of fuzzy logic controller, but it is not based on fuzzy logic.  相似文献   
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