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41.

Introduction

The purpose of this study was to develop an integrated methodology that links occupant injury risk functions, estimated in the laboratory, with real world medical treatment costs by using the abbreviated injury score (AIS). Using our model, the expected medical treatment costs for crash injuries to various body regions and of different severities can be investigated.

Methods

First, the simulation results are compared with NHTSA crash data. We used a modified kinematics simulation model that incorporates an F = Eb function as a supplement to the previous Steffan's model to obtain a more accurate acceleration history a(t). Second, head injury criteria HIC36 can be calculated from a(t), and we use the injury probability P as a function of HIC36, as proposed by Kuppa, to obtain the injury risk function for various AIS values. Third, medical treatment cost models for various AIS values can be calculated by using a regression cost model with real world data. Finally, the injury risk function and medical treatment cost models are linked through AIS values. We establish an integrated methodology and predict medical costs and car safety data using real world police reports, medical treatment costs, and laboratory simulation results.

Results

Using head injuries in frontal crashes as an example, we focus on simulation parameters for different vehicle models, with and without airbags. We specifically examine impact closing speed, Delta-V, and impact directions.

Conclusion

Simulation results can be used to supplement insufficient real crash data, in particular ΔV, and injury risk results from police crash reports.

Impact on industry

The proposed integrated methodology may provide the vehicle industry with a new safety assessment method. Real crash data coupling provides consumers with more realistic and applicable information.  相似文献   
42.
Tsai WT  Liu SC  Chen HR  Chang YM  Tsai YL 《Chemosphere》2012,89(2):198-203
Biochars have received increasing attention in recent years because of their properties pertaining to soil fertility and contaminant immobilization as well as serving as carbon sinks. In this work, a series of biochars were produced from dried swine manure waste by slow pyrolysis at different temperatures (i.e., 673-1073 K). The characterization of the resulting biochars was examined for its relevance to its potential use as soil amendment. It was found that the pore properties, ash contents and pH values of all swine-manure-derived biochars basically increased as temperature increased, while the yield and nitrogen/oxygen contents decreased with increasing temperature as a result of pyrolytic volatilization during pyrolysis. From the organic and inorganic elements analyses, the manure-derived biochar was rich in soil nutrients such as N, P, Ca, Mg, and K. Furthermore, the pore, surface and chemical properties were also consistent with the observations of the SEM-EDS, XRD and FTIR. This result suggested that the mesoporous manure-derived biochar could be used as an excellent medium to soil environment.  相似文献   
43.
A number of activated carbons derived from waste tires were further impregnated by gaseous elemental sulfur at temperatures of 400 and 650 degrees C, with a carbon and sulfur mass ratio of 1:3. The capabilities of sulfur diffusing into the micropores of the activated carbons were significantly different between 400 and 650 degrees C, resulting in obvious dissimilarities in the sulfur content of the activated carbons. The sulfur-impregnated activated carbons were examined for the adsorptive capacity of gas-phase mercuric chloride (HgC1) by thermogravimetric analysis (TGA). The analytical precision of TGA was up to 10(-6) g at the inlet HgCl2 concentrations of 100, 300, and 500 microg/m3, for an adsorption time of 3 hr and an adsorption temperature of 150 degrees C, simulating the flue gas emitted from municipal solid waste (MSW) incinerators. Experimental results showed that sulfur modification can slightly reduce the specific surface area of activated carbons. High-surface-area activated carbons after sulfur modification had abundant mesopores and micropores, whereas low-surface-area activated carbons had abundant macropores and mesopores. Sulfur molecules were evenly distributed on the surface of the inner pores after sulfur modification, and the sulfur content of the activated carbons increased from 2-2.5% to 5-11%. After sulfur modification, the adsorptive capacity of HgCl2 for high-surface-area sulfurized activated carbons reached 1.557 mg/g (22 times higher than the virgin activated carbons). The injection of activated carbons was followed by fabric filtration, which is commonly used to remove HgCl2 from MSW incinerators. The residence time of activated carbons collected in the fabric filter is commonly about 1 hr, but the time required to achieve equilibrium is less than 10 min. Consequently, it is worthwhile to compare the adsorption rates of HgCl2 in the time intervals of < 10 and 10-60 min.  相似文献   
44.
A Micro-Orifice Uniform Deposition Impactor (MOUDI) and a Nano-MOUDI were employed to determine the size-segregated mass distributions of ambient particulate matter (PM) and water-soluble ionic species for particulate constituents. In addition, gas precursors, including HCl, HONO, HNO3, SO2, and NH3 gases, were analyzed by an annular denuder system. PM size mass distribution, mass concentration, and ionic species concentration were measured during the day and at night during episode and non-episode periods in winter and summer. Average total suspended particle (TSP) concentrations during episode days in winter were as high as 153?±?33 μg/m3, and PM mass concentrations in summer were as low as one-third of that in winter. Generally, PM concentration at night was higher than that in the daytime in southern Taiwan during the sampling periods. In winter during the episode periods, the size-segregated mass distribution of PM mass concentration was mostly in the 0.32–3.2-μm range, and the PM concentration increased significantly in the range of 0.32–3.2 μm at night. Ammonium, nitrate, and sulfate were the dominant water-soluble ionic species in PM, contributing 34–48 % of TSP mass. High concentrations of ammonia (12.9–49 μg/m3) and SO2 (2.6–27 μg/m3) were observed in the gas precursors. The conversion ratio was high in the PM size range of 0.18–3.2 μm both during the day and at night in winter, and the conversion ratio of episode days was 20 % higher than that of non-episode days. The conversion factor was high for both nitrogen and sulfur species at nighttime, especially on episode days.  相似文献   
45.
The hysteresis of capillary pressure versus saturation (PS) relation is an important constitutive relation in multiphase flow, since the PS relation is widely used to predict PS relations in the simulation of the non-aqueous phase liquids (NAPLs). This work examined the performance of the scaling rule on predicting the PS relationship and then studied the joint impact of the scaling and hysteresis on the multiphase NAPL flow simulation. Various experimental PS values of distinct fluid pairs were compared with the scaled PS curves using the scaling rule. The comparison indicated that the prediction of PS is more accurate when the water–air PS curve is used to scale other PS curves. The joint impact of the scaling and hysteresis on the NAPLs flow simulation was then investigated by numerical simulation studies. The NAPL simulator was used to simulate the outcome of several scenarios based on a system with water–NAPL–air in a hypothetical sand tank. For both gasoline and trichloroethylene, the difference of the injected NAPL volume between no hysteretic and hysteretic simulations over a given time period was the smallest when the water–air PS curve was used to scale other P–S curves. Simulation results of this study are valuable references for predicting the distribution of NAPLs.  相似文献   
46.
Hourly concentrations of ozone (O(3)), 55 volatile organic compounds (VOCs, ozone precursors) and nitrogen oxides (NOx) were measured at an upwind urban site, a downwind suburban site, and a rural site in central Taiwan, from January 2003 to December 2006. VOC and NOx mean concentrations showed a gradient from high to low across the urban (56 ppb and 34 ppb), suburban (38 ppb and 27 ppb) and rural sites (25 ppb and 21 ppb) but a reverse gradient in ozone across these sites (24, 27, and 29 ppb, respectively). Although there was about twice the difference in VOC concentrations between the urban and rural sites, nearly 65% ozone formation potential was contributed to by the same 9 VOCs. Seasonal patterns showed peak ozone levels in autumn and minima in summer at the urban site, but minima in winter at the downwind suburban and rural sites. Ozone precursor levels, on the other hand, were lowest in summer and highest in winter. The diurnal pattern showed that ozone levels peaked one hour later at the rural site than at the urban site. The ethylbenzene to m,p-xylene ratio, an indicator of the age of the air mass, increased from 0.4 at the urban site to 0.6 at the suburban site and 0.8 at the rural site during daily peak ozone times. This finding suggests the transport of ozone and precursors from upwind to downwind producing elevated ozone levels in the suburban and rural areas. Ozone episodes occurred mostly in days with a mean midday UV index of 6.5 (1 UV index=100 J m(-2)) and wind speed at 1.3 m s(-1) at all three sites.  相似文献   
47.
The fate of herbicides trifluralin, pendimethalin, alachlor and metolachlor in paddy field soils amended with plant materials was investigated. The plant materials were purple sesbania, vegetable soybean and rice straw. The investigation was performed at two temperatures (25 and 40 degrees C) and two soil water moistures (60 and 90% water-holding capacity). The results showed linear and Freudlich equations described the adsorption of amide compound to soil. Adsorption coefficient (K(d)) fit to linear equation were in general greater in plant material-amended soils than in non-amended soil, especially in soil amending with rice straw. Increasing temperature and soil water moisture content shortened the half-lives of compounds in various treated soils. The movement of compounds in the soil columns showed the maximum distribution of aniline type compound, trifluralin and pendimethalin, appeared at the upper top of 0 to 5 and 0 to 10 cm of soil column, respectively, and of anilide type, alachlor and metolachlor, were distributed at 0 to 25 cm of the soil column. The mobility of chemicals in the different treated soils was simulated by the behavior assessment model (BAM). There was no significant difference among different plant material incubated soils on dissipation and mobility of compounds in soils.  相似文献   
48.
Lin CW  Cheng YW  Tsai SL 《Chemosphere》2007,69(9):1485-1491
The influence of zinc, manganese, and nickel on the degradation of MTBE (methyl tert-butyl ether), by an aerobic MTBE-degrading strain, Ochrobactrum cytisi, were investigated. The result showed that unlike previous findings, O. cytisi was able to degrade MTBE through direct metabolism when MTBE was present as the only carbon source. The degradation rate of MTBE was rapid, completed within 80 h. MTBE biodegradation by this strain was stimulated at low concentrations of Zn(2+) (1-5 mg l(-1)) and Mn(2+) (1-5 mg l(-1)) but inhibited at high concentrations of Zn(2+) (20 mg l(-1)) and Mn(2+) (20 mg l(-1)), and at low concentration of Ni(2+) (1-4 mg l(-1)). Kinetic parameters for MTBE degradation in the presence or absence of metals were obtained through nonlinear regression and a least-square minimization procedure. In all cases, a good agreement was achieved between kinetic simulations and experimental results.  相似文献   
49.
Estimation of waste generation from floods   总被引:1,自引:0,他引:1  
A framework of correlation for estimating the amount of waste generation from floods is developed. Flood waste data were collected from four recent typhoons in Taiwan. Parameters affecting the flood waste are analyzed. Population density, flooded area and amount of total rainfall are chosen as the correlating parameters for the model development, and regression diagnostics are performed to check the validity of the collected data. The simple linear model is shown to be incapable of correlating the flood waste data. An exponential model is proposed and shown to give acceptable correlation with the flood waste data spanning five orders of magnitude. The model can be useful in the planning of waste cleanup after floods.  相似文献   
50.
ABSTRACT: Major parameters and optimum storage volumes of rooftop rain water harvesting systems (RRWHSs) have not been investigated in detail in Taiwan. Accordingly, the four major parameters of RRWHSs were herein identified and elucidated using a simulation method. Because the performance of the RRWHSs is sensitive to the runoff coefficient, a field experiment was conducted to determine the runoff coefficient more precisely for various types of roofs. A simulation model including production theory was developed and employed to estimate the most cost effective combination of the roof area and the storage capacity that best supplies a specific volume of water. Consequently, the expansion path of optimum solutions for different volumetric reliability of water supply can be determined. Additionally, the method based on the marginal rate of substitution can be used for determining the rational volumetric reliability. The procedures developed herein constitute an effective tool for preliminarily estimating the most satisfactory storage capacity of any specific roof area and for determining the rational reliability of a corresponding water supply.  相似文献   
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