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The numbers of traffic accidents and its associated mortalities are decreasing every year in Japan. However, there continue to be cases of deaths and injuries caused by malicious driving including drunk driving. The forensic autopsy of traffic accident victims is important to determine the cause of death as well as the responsibility of traffic accidents. In this study, we investigated the cases of forensic autopsies related to traffic accidents, reported between 2013 and 2017, at the Department of Legal Medicine of Tokyo Women's Medical University. In this period, 22 autopsies were performed for traffic accidents; however, only 6 of them were associated with alcohol consumption. Most traffic accidents occurred during the night, and in one case, the victim was found lying on the road. Furthermore, there were 4 cases in which drugs in the blood or urine of the victim were detected; however, the actual relationship with the cause of death and traffic accident was not identified. It was also found necessary to take measures against pedestrian drinking. Moreover, only a few drugs led to a decrease in driving ability, highlighting the necessity of further data is necessary to provide insights into the type of drug consumed and the cause of accident.  相似文献   
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For the theoretical consideration of a system for reducing skin friction, a mathematical model was derived to represent, in a two-phase field, the effect on skin friction of the injection of micro air bubbles into the turbulent boundary layer of a liquid stream. Based on the Lagrangian method, the equation of motion governing a single bubble was derived. The random motion of bubbles in a field initially devoid of bubbles was then traced in three dimensions to estimate void fraction distributions across sections of the flow channel, and to determine local bubble behavior. The liquid phase was modeled on the principle of mixing length. Assuming that the force exerted on the liquid phase was equal to the fluid drag generated by bubble slip, an equation was derived to express the reduction in turbulent shear stress. Corroborating experimental data were obtained from tests using a cavitation tunnel equipped with a slit in the ceiling from which bubbly water was injected. The measurement data provided qualitative substantiation of the trend shown by the calculated results with regard to the skin friction ratio between cases with and without bubble injection as function of the distance downstream from the point of bubble injection.List of symbols B law of wall constant - C f local coefficient of skin friction - C f0 local coefficient of skin friction in the absence of bubbles - d b bubble diameter [m] - g acceleration of gravity [m/s2] - k 1 k4 proportional coefficient - k L turbulent energy of the liquid phase [m2/s2] - L representative length [m] - l b mean free path of a bubble [m] - m A added mass of a single bubble [kg] - m b mass of a single bubble [kg] - N x ,N y ,N z force perpendicular to the wall or ceiling exerted on a bubble adhering to that wall or ceiling [N] - P absolute pressure [Pa] - Q G rate of air supply [/min] - q L (i) turbulent velocity at the ith time increment [m/s] - R> ex Reynolds number defined by Eq. 32 - T *L integral time scale of the liquid phase [s] - U velocity of the main stream [m/s] - ,¯v,¯w time-averaged velocity components [m/s] - u,v,w turbulent velocity components [m/s] - û L ,vL root mean square values of liquid phase turbulence components in thex- and y-directions [m/s] - V volume of a single bubble [m3] - X,Y,Z components of bubble displacement [m] - x s ,y s ,z s coordinate of a random point on a sphere of unit diameter centered at the coordinate origin - root mean square of bubble displacement in they-direction in reference to the turbulent liquid phase velocity [m] - local void fraction - m mean void fraction in a turbulent region - regular random number - R v increment of the horizontal component of the force acting on a single bubble, defined by Eq. 22 [N] - t time increment [s] - 1 reduction of turbulent stress [N/m2] - L rate of liquid energy dissipation [m2/s3] - m coefficient defined by Eq. 30 - law of wall constant in the turbulent region in absence of bubbles - 1 law of wall constant in the turbulent region in presence of bubbles  相似文献   
3.
Many industrial products made from fossil fuels cause the problems of global warming, depletion of fossil fuel resources and decrease of the land by landfill. In this report, the amounts of CO2 emissions as the environmental load and the specific energy consumptions as the depletion of fossil fuel resources of biodegradable plastics and conventional plastic as food trays are compared using life cycle assessment methodology. The amount of CO2 emission of PHB (poly(3-hydroxybutyrate-co-4-hydroxybutyrate)) tray was the smallest among those of trays of other plastics. The specific energy consumption of SPCL (starch/polycaprolactone) was the smallest among those of trays of other plastics. It clearly reveals that the utilization of the biodegradable plastics is an effective way of alternatives of the conventional plastics.  相似文献   
4.
她就像一抹燃烧的嫣红,溶化冬日的冰雪,也融化你心中渴望战斗的血液。她是火焰的女皇。  相似文献   
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A method of enveloping the hull with a sheet of microbubbles is discussed. It forms part of a study on means of reducing the skin friction acting on a ship's hull. In this report, a bubble traveling through a horizontal channel is regarded as a diffusive particle. Based on this assumption, an equation based on flow flux balance is derived for determining the void fraction in approximation. The equation thus derived is used for calculation, and the calculation results are compared with reported experimental data. The equation is further manipulated to make it compatible with a mixing length model that takes into account the presence of bubbles in the liquid stream. Among the factors contained in the equation thus derived, those affected by the presence of bubbles are the change of mixing length and the difference in the ratio of skin friction between cases with and without bubbles. These factors can be calculated using the mean void fraction in the boundary layer determined by the rate of air supply into the flow field. It is suggested that the ratio between boundary layer thickness and bubble diameter could constitute a significant parameter to replace the scale effect in estimating values applicable to actual ships from corresponding data obtained in model experiments.List of symbols a 1 proportionality constant indicating directionality of turbulence - B law-of-the-wall constant - C f local skin-friction coefficient in the presence of bubbles - C f0 local skin-friction coefficient in the absence of bubbles - d b bubble diameter (m) - g acceleration of gravity (m/s2) - j g flow flux of gas phase accountable to buoyancy (m/s) - j t flow flux of gas phase accountable to turbulence (m/s) - k 4 constant relating reduction of liquid shear stress by bubble presence to decrease of force imparted to bubble by its displacement due to turbulence - l b mixing length of gas phase (m) - l m mixing length of liquid phase (m) - l mb diminution of liquid phase mixing length by bubble presence (m) - Q G rate of air supply to liquid stream (l/min) - q /g velocity of bubble rise (m/s) - 2R height of horizontal channel (m) - T * integral time scale (s) - U m mean stream velocity in channel (m/s) - U friction velocity in channel (m/s) - V volume of a bubble (m3) - u, ¯ v time-averaged stream velocities inx- andy-directions, respectively (m/s) - u, v turbulent velocity components inx- andy-directions, respectively (m/s) - v root mean square of turbulence component in they-direction (m/s) - root mean square of bubble displacement iny-direction with reference to turbulent liquid phase velocity (m) - y displacement from ceiling (m) - local void fraction - m mean void fraction in boundary layer - m constant relating local void fraction to law-of-the-wall constant - t reduction of turbulent stress (N/m2) - law-of-the-wall constant in turbulent liquid region in absence of bubbles - 1 law-of-the-wall constant in turbulent liquid region in presence of bubbles - 2 law-of-the-wall constant in gas phase - m constant indicating representative turbulence scale (m) - viscosity (Pa × s) - v kinematic viscosity (m2/s) - density (kg/m3) Suffixes G gas - L liquid - 0 absence of bubbles  相似文献   
7.
Yuki 《家用汽车》2008,(12):128-128
蒋大维现在后悔得要死。他那张沮丧的脸,仿佛刚与500万彩票失之交臂。 “小娴,他是怎么回事,一副想要自杀的样子。”大维的死党杨晓磊刚刚来到聚会地点,有点搞不清状况。 “他啊,昨天跟人去买了一辆车,回来就这样了。”小娴一副无奈的样子。 “是不是拿到了很大的优惠啊,恩,我能理解他的心情。”蒋大维老吹嘘自己买车占了天大的便宜,看到别人的东西更便宜肯定是欲哭无泪。  相似文献   
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