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81.
AbstractThis special issue brings together material culture and the history of emotions to explore the emotive properties of textiles in Northwest Europe from the seventeenth to the early twentieth centuries. It is the first detailed study of the changing emotional meanings of a particular type of material - textiles - from the metallic lace adorning christening robes, to union cloth burial clothes. The six articles are contributed by historians and museum professionals from a range of disciplines. These authors harness a variety of sources and methodologies to interrogate the emotional repertoire of textiles, and the emotive process of research itself. 相似文献
82.
Time-variable simulation of soil vapor intrusion into a building with a combined crawl space and basement 总被引:1,自引:0,他引:1
A time-variable one-dimensional model (called ViM for Vapor Intrusion Model)to predict indoor vapor concentrations in a dwelling with a combined basement and crawl space has been developed. ViM predicts vapor concentrations in each of the three compartments. Volatile chemicals that intrude into the dwelling are assumed to originate from soil, groundwater (where an attenuating plume is simulated), or ambient air. Processes included in the model are advection, diffusion, biodecay, and adsorption in the soil column; transport by diffusion and advection into individual crawl space and basement compartments; advection from each compartment into an overlying dwelling space; and exchange of ambient air and indoor air. The time-variable concentration fields are solved by first transforming the partial and ordinary differential equations into Laplace space, solving the resulting ordinary differential equations or algebraic equations, and numerically inverting those equations. This approach was an expedient way of handling the coupling between the subsurface and the dwelling. ViM was applied to a building (Building 20) located at the former Moffett Field Naval Air Station, in Mountain View, CA. The building is a former bachelor officer's quarters. The shallow groundwater beneath the building is contaminated with a number of volatile chemicals, including trichloroethene, cis-1,2-dichloroethene, and trans-1,2-dichloroethene, all of which were simulated. Using indoor air data collected in 2003-2004, and other field data collected prior to that time, the accuracy of the model's predictions was demonstrated. ViM's results were also compared against a version of the steady-state Johnson and Ettinger model (1) that was modified to accommodate a dwelling with a combined crawl space and basement (called the JEM model in this paper). The predictions from the JEM model were consistently higher than the predictions from ViM, but still near the upper range of the observed data. 相似文献
83.
O'Neill SM Lamb BK Chen J Claiborn C Finn D Otterson S Figueroa C Bowman C Boyer M Wilson R Arnold J Aalbers S Stocum J Swab C Stoll M Dubois M Anderson M 《Environmental science & technology》2006,40(4):1286-1299
The Community Multi-Scale Air Quality (CMAQ) modeling system was used to investigate ozone and aerosol concentrations in the Pacific Northwest (PNW) during hot summertime conditions during July 1-15, 1996. Two emission inventories (El) were developed: emissions for the first El were based upon the National Emission Trend 1996 (NET96) database and the BEIS2 biogenic emission model, and emissions for the second El were developed through a "bottom up" approach that included biogenic emissions obtained from the GLOBEIS model. The two simulations showed that elevated PM2.5 concentrations occurred near and downwind of the Interstate-5 corridor along the foothills of the Cascade Mountains and in forested areas of central Idaho. The relative contributions of organic and inorganic aerosols varied by region, but generally organic aerosols constituted the largest fraction of PM2.5. In wilderness areas near the 1-5 corridor, organic carbon from anthropogenic sources contributed approximately 50% of the total organic carbon with the remainder from biogenic precursors, while in wilderness areas in Idaho, biogenic organic carbon accounted for 80% of the total organic aerosol. Regional analysis of the secondary organic aerosol formation in the Columbia River Gorge, Central Idaho, and the Olympics/Puget Sound showed that the production rate of secondary organic carbon depends on local terpene concentrations and the local oxidizing capacity of the atmosphere, which was strongly influenced by anthropogenic emissions. Comparison with observations from 12 IMPROVE sites and 21 ozone monitoring sites showed that results from the two El simulations generally bracketed the average observed PM parameters and that errors calculated for the model results were within acceptable bounds. Analysis across all statistical parameters indicated that the NW-AIRQUEST El solution performed better at predicting PM2.5, PM1, and beta(ext) even though organic carbon PM was over-predicted, and the NET96 El solution performed better with regard to the inorganic aerosols. For the NW-AIRQUEST El solution, the normalized bias was 30% and the normalized absolute error was 49% for PM2.5 mass. The NW-AIRQUEST solution slightly overestimated peak hourly ozone downwind of urban areas, while the NET96 solution slightly underestimated peak values, and both solutions over-predicted average 03 concentrations across the domain by approximately 6 ppb. 相似文献
84.
Yoder SF Henning WR Mills EW Doores S Ostiguy N Cutter CN 《Journal of food protection》2012,75(1):14-21
Numerous antimicrobial interventions are capable of reducing the prevalence of harmful bacteria on raw meat products. There is a need to identify effective and inexpensive antimicrobial interventions that could, in practice, be used in very small meat plants because of limited financial, space, and labor resources. Eight antimicrobial compounds (acetic acid, citric acid, lactic acid, peroxyacetic acid, acidified sodium chlorite, chlorine dioxide, sodium hypochlorite, and aqueous ozone) were applied at various concentrations with small, hand-held spraying equipment, and bactericidal effectiveness was examined. Beef plate pieces were inoculated with fecal slurry containing a pathogen cocktail (Escherichia coli O157:H7, Salmonella Typhimurium, Campylobacter coli, and Campylobacter jejuni) and natural populations of aerobic plate counts, coliforms, and E. coli. Antimicrobial solutions were applied to beef surfaces via a portable, pressurized hand-held spray tank, and treated surfaces were subjected to appropriate methods for the enumeration and isolation of pathogens and hygiene indicators. Relative antimicrobial effectiveness was determined (from greatest to least): (i) organic acids, (ii) peroxyacetic acid, (iii) chlorinated compounds, and (iv) aqueous ozone. Using the equipment described, a 2% lactic acid rinse provided 3.5- to 6.4-log CFU/cm(2) reductions across all bacterial populations studied. Conversely, aqueous ozone yielded 0.02- to 2.9-log CFU/cm(2) reductions in pathogens and hygiene indicators, and did not differ significantly from a control tap water rinse (P = 0.055 to 0.731). This 2% lactic acid rinse will be subsequently combined with a previously described water wash to create a multistep antimicrobial intervention that will be examined under laboratory conditions and validated in very small meat plants. 相似文献
85.
A suite of five representative samples from a freshly opened adit in the Fording River Coal Deposits, BC was taken at selected distances from the surface to the 45.7 m depth of the seam to provide material for studying the progress of coal oxidation under natural conditions. The ‘as-mined’ < 28 US mesh material from each sample was subjected to standard proximate, ultimate and free swelling index (FSI) analyses, followed by quantitative evaluation of surface oxidation states, using several techniques concurrently. Correlation of the results indicates a progressive decrease in oxidation from a very high level for the surface sample, with FSI 1, to a relatively low oxidation level for samples taken at 22.9 m and 45.7 m distances. Solvent extracts show a progressive decrease in the ratio of soluble aliphatic-to-aromatic compounds from surface to deep coal and in the amount of carboxylate groups. Oxidized coals require pretreatment with dilute acids in order to convert phenolate and carboxylate salts into phenols and carboxylic acids respectively; the analytical results for the latter are then increased by a factor of 4–6. 相似文献
86.
Distributed databases allow us to integrate data from different sources which have not previously been combined. In this article, we are concerned with the situation where the data sources are held in a distributed database. Integration of the data is then accomplished using the Dempster–Shafer representation of evidence. The weighted sum operator is developed and this operator is shown to provide an appropriate mechanism for the integration of such data. This representation is particularly suited to statistical samples which may include missing values and be held at different levels of aggregation. Missing values are incorporated into the representation to provide lower and upper probabilities for propositions of interest. The weighted sum operator facilitates combination of samples with different classification schemes. Such a capability is particularly useful for knowledge discovery when we are searching for rules within the concept hierarchy, defined in terms of probabilities or associations. By integrating information from different sources, we may thus be able to induce new rules or strengthen rules which have already been obtained. We develop a framework for describing such rules and show how we may then integrate rules at a high level without having to resort to the raw data, a useful facility for knowledge discovery where efficiency is of the essence. © 1997 John Wiley & Sons, Inc. 相似文献
87.
An investigation of how emergency vehicle lighting (EVL) can be improved is reported with reference to an analysis of police vehicle road traffic accidents (Study 1). In Study 2, 37 regular drivers were shown film clips of a marked police vehicle, in which flash rate (1 Hz, 4 Hz) and pattern (single, triple pulse) were varied on the blue Light Emitting Diode (LED) roofbar. Results indicate a 4 Hz flash rate conveys greater urgency than a 1 Hz rate, while a 1 Hz, single flash combination was ranked the least urgent of all combinations. Participants claimed they would leave significantly more space before pulling out in front of an approaching police car (gap acceptance) in the 4 Hz single pulse condition in comparison to other EVL combinations. The preliminary implications for which flash characteristics could prove most optimal for emergency service use are discussed with regard to effects on driver perception and expected driving behaviour. 相似文献
88.
This paper reviews the literatures on housing and ontological security and the meaning of the home in order to derive specific examples of the psycho-social benefits of the home which can be assessed through empirical research. A postal survey measuring these psycho-social benefits was distributed to a random sample of adults in eight local authority districts in West Central Scotland. From the responses to the survey, three factors were constructed relating to the home as a haven, as a locus of autonomy and as a source of status for the occupants. Multivariate analysis showed that housing tenure is less important as an influence upon the attainment of psycho-social benefits from the home than the neighbourhood context and the incidence of problems with the home. Further, those factors negatively associated with psycho-social benefits appear to be more important than those factors positively associated with such benefits. This suggests that future research should focus on the fact that what detracts from psycho-social benefits may be more important than what contributes to them. A further important finding is that, after controlling for other influences, people living alone derive more benefits from the home as a haven and as a locus of autonomy than people in multi-person households. 相似文献
89.
Golden Charles J.; Kuperman Sally K.; Osmon David C. 《Canadian Metallurgical Quarterly》1980,11(5):797
Sought to identify the relative standing of clinical psychology programs by evaluating their frequency of publication in the major clinical journals. In addition, the relative contribution of university programs, hospital programs, medical centers, and other institutions to the clinical literature was investigated. It was found that although American Psychological Association (APA)-approved university clinical programs are responsible for the largest number of articles in the sample examined, (14 journals for the years 1975, 1976, and 1977), 6 of every 10 articles were published either by non-APA-approved academic programs or by individuals in other institutional settings. The general reputation of universities did not reflect their productivity in the clinical journals. The article includes an analysis of the major sources of publication in the clinical literature and an evaluation of the meaning of these findings for clinical psychology. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
Golden Charles J.; Kuperman Sally K.; MacInnes William D.; Moses James A. 《Canadian Metallurgical Quarterly》1981,49(4):606
Cross-validated the use of a short form of the Halstead Category Test as suggested by D. A. Calsyn et al (see record 1981-02450-001). For 60 Ss (mean age 36.72 yrs), it was found that the total score estimated from their formula (based on the 1st 4 subtests of the Category Test) correlated .88 with the overall score. The formula was cross-validated in 3 samples with all correlations above .83. It was found that the formula could reliably predict who would exceed the cutoff of the entire test, with an overall accuracy across the 4 samples of 184 out of 205. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献