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701.
Objective: The shape of the current physical and computational surrogates of children used for restraint system assessments is based largely on standard anthropometric dimensions. These scalar dimensions provide valuable information on the overall size of the individual but do not provide good guidance on shape or posture. This study introduced the development of a parametric model that statistically predicts individual child body shapes in seated postures with a few given parameters.

Methods: Surface geometry data from a laser scanner of children ages 3 to 11 (n = 135) were standardized by a 2-level fitting method using intermediate templates. The standardized data were analyzed by principal component analysis (PCA) to efficiently describe the body shape variance. Parameters such as stature, body mass index, erect sitting height, and 2 posture variables related to torso recline and lumbar spine flexion were associated with the PCA model using regression.

Results: When the original scan data were compared with the predictions of the model using the given subject dimensions, the average root mean square error for the torso was 9.5 mm, and the 95th percentile error was 17.35 mm.

Conclusions: For the first time, a statistical model of child body shapes in seated postures is available. This parametric model allows the generation of an infinite number of virtual children spanning a wide range of body sizes and postures. The results have broad applicability in product design and safety analysis. Future work is needed to improve the representation of hands and feet and to extend the age range of the model. The model presented in this article is publicly available online through HumanShape.org.  相似文献   

702.
Cracking, steam reforming, dry reforming, and combined steam and dry reforming of toluene in model syngas were performed using catalysts to simulate tar removal produced during biomass gasification. The catalysts were prepared by adding Ru, Ca, and Mn to Ni-based catalysts, and their properties were measured using BET, pulse CO chemisorption, XRD and TG. In steam and dry reforming of toluene, a high toluene conversion was observed with increasing Ca content in the catalyst and catalysts containing Ca showed a higher activity than those containing Mn. In combined steam-dry reforming with syngas, 1%CaNiRu/Al2O3 indicated a conversion of 93.9% at 800°C.  相似文献   
703.
In this study, mercury (Hg) leaching characteristics of the waste treatment residues (fly ash, bottom ash, sludge, and phosphor powder) generated from various sources (municipal, industrial, medical waste incinerators, sewage sludge incinerator, oil refinery, coal-fired power plant, steel manufacturing plant, fluorescent lamp recycler, and cement kiln) in Korea were investigated. First, both Hg content analysis and toxicity characteristic leaching procedure (TCLP) testing was conducted for 31 collected residue samples. The Hg content analysis showed that fly ash from waste incinerators contained more Hg than the other residue samples. However, the TCLP values of fly ash samples with similar Hg content varied widely based on the residue type. Fly ash samples with low and high Hg leaching ratios (RL) were further analyzed to identify the major factors that influence the Hg leaching potential. Buffering capacity of the low-RL fly ash was higher than that of the high-RL fly ash. The Hg speciation results suggest that the low-RL fly ashes consisted primarily of low-solubility Hg compounds (Hg2Cl2, Hg0 or HgS), whereas the high-RL fly ashes contain more than 20% high-solubility Hg compounds (HgCl2 or HgSO4).  相似文献   
704.

An initial reclamation of the Young Dong coal mine site, located in northeastern South Korea, was completed in 1995. Despite the filling of the adit with limestone, acid rock drainage (ARD) enters Young Dong tributary and is then discharged to Imgok Creek. This ARD carries an average of 500 mg CaCO3/l of mineral acidity, primarily as Fe(II) and Al. Before spring runoff, the flow of Imgok Creek is 3.3–4 times greater than that of the tributary and has an alkalinity of 100 mg CaCO3/l, which is sufficient to eliminate the mineral acidity and raise the pH to about 6.5. From April through September 2008, there were at least two periods of high surface flow that affects the flow of ARD from the adit. Flow of ARD reaches 2.8 m3/min during spring runoff. This raised the concentrations of Fe and Al in the confluence with Imgok Creek. However, by 2 km downstream the pH of the Imgok Creek is 6.5 and only dissolved Fe is above the Korean drinking water criteria (0.30 mg/l). This suggests only a minor impact of Young Dong Creek water on Imgok Creek. Acid digestion of the sediments in Imgok Creek and Young Dong Tributary reveals considerable abundances of heavy metals, which could have a long-term impact on water quality. However, several water-based leaching tests, which better simulate the bioavailable metals pool, released only Al, Fe, Mn, and Zn at concentrations exceeding the criteria for drinking water or aquatic life.

  相似文献   
705.
The objectives of this study were to survey elementary school students regarding the environmental conditions of their elementary schools and to assess the relationship between air pollution and allergic disease using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Therefore, this study was designed as a cross-sectional study. In this study, seven elementary schools were selected and they were classified into three categories. The selection included one school with no traffic-related or other pollutants, three with traffic-related pollutants, and three with traffic-related and other pollutants from industrial and filling station sources. The ISAAC questionnaire survey was given to all of the students except to those in the 1st grade who were presumed to be less likely to be exposed to the school environment than the remainder of the students attending those seven schools. The assessment of allergic disease was conducted on a total of 4,545 students. Three school zones with critical exposure were selected within each school and they were evaluated based on the levels of black carbon (BC), PM10, SO2, NO2, and O3. There was a significant increase in the risks based on the odds ratios of treatment experiences (within 1 year) for allergy-related diseases such as asthma and allergic rhinitis (a) in the school group with traffic-related pollutants and the school group with complex pollutants were 2.12 (1.41–3.19) and 1.59 (1.06–2.37), respectively, in comparison to the school groups with no exposure to pollutants. This was determined based on the odds ratio of symptoms and treatment experiences for allergy-related diseases by group based on the home town zone as a reference. Also, in the case of atopic dermatitis, the odds ratio of treatment experiences (within 1 year) was 1.42 (1.02–1.97), which indicated elevated risks compared to the students in the S1 school. A regression analysis was used to assess the relationship between the substances and the symptomatic experiences within the last year. There were significant increases in the odds ratio of the symptoms associated with allergic rhinitis and the BC and SO2 in the complex pollution areas. The results of the assessment of the relationship between atopic dermatitis-associated symptoms and O3 showed that the odds ratio increased with statistical significance.  相似文献   
706.
Product quality-based eco-efficiency applied to digital cameras   总被引:1,自引:0,他引:1  
When calculating eco-efficiency, there are considerable confusion and controversy about what the product value is and how it should be quantified. We have proposed here a quantification method for eco-efficiency that derives the ratio of the multiplication value of the product quality and the life span of a product to its whole environmental impact based on Life Cycle Assessment (LCA). In this study, product quality was used as the product value and quantified by the following three steps: (1) normalization based on a value function, (2) determination of the subjective weighting factors of the attributes, and (3) calculation of product quality of the chosen products. The applicability of the proposed method to an actual product was evaluated using digital cameras. The results show that the eco-efficiency values of products equipped with rechargeable batteries were higher than those products that use alkaline batteries, because of higher quality values and lower environmental impacts. The sensitivity analysis shows that the proposed method was superior to the existing methods, because it enables to identify the quality level of the chosen products by considering all products that have the same functions in the market and because, when adding a new product, the calculated quality values in the proposed method do not have to be changed.  相似文献   
707.
In this study, the photochemical degradation of livestock wastewater was carried out by the Fenton and Photo-Fenton processes. The effects of pH, reaction time, the molar ratio of Fe(2 +)/H(2)O(2), and the Fe(2 +) dose were studied. The optimal conditions for the Fenton and Photo-Fenton processes were found to be at a pH of 4 and 5, an Fe(2 +) dose of 0.066 M and 0.01 M, a concentration of hydrogen peroxide of 0.2 M and 0.1 M, and a molar ratio (Fe(2 +)/H(2)O(2)) of 0.33 and 0.1, respectively. The optimal reaction times in the Fenton and Photo-Fenton processes were 60 min and 80 min, respectively. Under the optimal conditions of the Fenton and Photo-Fenton processes, the chemical oxygen demand (COD), color, and fecal coliform removal efficiencies were approximately 70--79, 70--85 and 96.0--99.4%, respectively.  相似文献   
708.
Perchlorate, a known thyroid endocrine disruptor, contaminates surface waters near military instillations where solid fuel rocket motors are manufactured or assembled. To assess potential perchlorate exposure to fish and the human population which may feed on them, fish were collected around the Naval Weapons Industrial Reserve Plant in McLennan County, TX, and analyzed for the presence of the perchlorate anion. The sampling sites included Lake Waco and Belton Lake, and several streams and rivers within their watersheds. The general tendency was that perchlorate was only found in a few species sampled, and perchlorate was not detected in every individual within these species. When detected in the fish, perchlorate tissue concentrations were greater than that in the water. This may be due to highly variable perchlorate concentrations in the water coupled with individual-level variation in elimination from the body, or to routes of exposure other than water.  相似文献   
709.
In this paper, an assessment method is proposed for ecodesign improvement options using global warming and economic performance indicators. A reduction in the GHG emissions in the entire life cycle stages of a product was chosen as the global warming performance of the product. The external cost which converts the external effect of global warming into a monetary value was chosen as the global warming performance indicator in order to measure the performance of the GHG reduction of the product. The life cycle cost (LCC) of the product was chosen as the economic performance indicator to measure the performance of the life cycle cost reduction of the product. The assessment method based on the two performance indicators was applied to the liquid crystal display (LCD) panel for a case study.  相似文献   
710.
There are two approaches in the application of satellite sensors to marine pollution studies. Satellite sensors are used to observe and characterize ocean pollutants such as industrial wastes and oil. in addition, satellite observations provide information useful in illuminating processes such as eutrophi-cation or air-sea exchange of CO2, that are important in determining the distribution and fate of pollutants.

Satellite technology is an important tool in monitoring and studying ocean pollution. Visible sensors have been used to observe and characterize sewage sludge and industrial wastes dumped at sea. Oil slicks have been observed with Landsat, AVHRR and SAR imagery. Besides directly detecting pollutants, satellite sensors are useful for analyzing ocean processes that are influential in the fate of pollutants. These processes include eutrophication of coastal waters and the distribution of suspended matter. the fate of excess CO2 can be addressed using scatterometer-derived estimates of wind speeds to determine the CO2 exchange coefficient at the sea surface on a global scale.  相似文献   
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