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271.
<正>Chinese Journal of Population Resources and Environment,Print ISSN 1004-2857,Online ISSN 2325-4262,Volume 11,2013.Chinese Journal of Population Resources and Environment(www.tandfonline.com/tpre)is a peer-reviewed journal published in March,June,September,and December by TaylorFrancis,4 Park Square,Milton Park,Abingdon,Oxon,OX14 4RN,UK.  相似文献   
272.
Under the pressure of sustained growth in energy consumption in China, the implementation of a carbon pricing mechanism is an effective economic policy measure for promoting emission reduction, as well as a hotspot of research among scholars and policy makers. In this paper, the effects of carbon prices on Beijing’s economy are analyzed using input–output tables. The carbon price costs are levied in accordance with the products’ embodied carbon emission. By calculation, given the carbon price rate of 10 RMB/t-CO2, the total carbon costs of Beijing account for approximately 0.22–0.40% of its gross revenue the same year. Among all industries, construction bears the largest carbon cost. Among export sectors, the coal mining and washing industry has much higher export carbon price intensity than other industries. Apart from traditional energy-intensive industries, tertiary industry, which accounts for more than 70% of Beijing’s economy, also bears a major carbon cost because of its large economic size. However, from 2007 to 2010, adjustment of the investment structure has reduced the emission intensity in investment sectors, contributing to the reduction of overall emissions and carbon price intensity.  相似文献   
273.
In order to analyze the factors influencing carbon emissions in the region of Beijing–Tianjin–Hebei and to explore the pathways to developing a low-carbon economy, this paper begins with the terminal energy consumption of three industries and residential consumption, and constructs an identical equation which is composed of population size, level of economic development, energy intensity, the proportion of energy consumption, energy structure, and the coefficient of carbon emissions. Based on the data of terminal energy consumption during 2000–2012, various factors are analyzed and their contribution is measured by Logarithmic Mean Divisia Index (LMDI). The results show that the levels of population and economy have a positive driving effect while energy intensity, energy structure, and carbon intensity have a negative driving effect; the proportion of energy consumption had a negative driving effect prior to 2006, then changed to positive. Among suggestions for a low-carbon economy are controlling population size, improving the quality of economic development, supporting research into new energy technology, accelerating regional integration and optimizing industrial structure, and enhancing environmental protection and spreading the concept of a low-carbon economy.  相似文献   
274.
275.
In order to investigate the effects of branch tunnels on explosion propagation, experiments were performed in five different configuration tunnels (straight configuration and configurations with 1 branch, 2 branches, 3 branches and 4 branches). Pressure and flame transducers were used to record the history of the pressure development and track the velocity of the flame front. It was shown that the branch tunnels had ability to enhance the maximum overpressure, rate of overpressure rise, and deflagration index (KG) of the gasoline–air mixture explosion due to the turbulence induced by the branch tunnels. The overpressure rise rate and KG of the explosion increased as a function of the number of branch tunnels. Experiments also showed that the maximum flame speed increased as the branch number increasing from 0 to 3 due to the enlargement of turbulence induced by the branch tunnels. However, an increase of branch number did not always lead to an enhancement of flame speed because the heat loss was intensified resulting from the increase of flame surface caused by the branch tunnels. When the number of branch tunnels exceeded 3, the maximum flame speed dropped.  相似文献   
276.
The finite difference time domain method (FDTD) is frequently used for the numerical solution of a wide variety of electromagnetic (EM) problems and, among them, those concerning human exposure to EM fields. In many practical cases related to the assessment of occupational EM exposure, large simulation domains are modeled and high space resolution adopted, so that strong memory and central processing unit power requirements have to be satisfied. To better afford the computational effort, the use of parallel computing is a winning approach; alternatively, subgridding techniques are often implemented. However, the simultaneous use of subgridding schemes and parallel algorithms is very new. In this paper, an easy-to-implement and highly-efficient parallel graded-mesh (GM) FDTD scheme is proposed and applied to human–antenna interaction problems, demonstrating its appropriateness in dealing with complex occupational tasks and showing its capability to guarantee the advantages of a traditional subgridding technique without affecting the parallel FDTD performance.  相似文献   
277.
In vehicle–pedestrian collisions, lower extremities of pedestrians are frequently injured by vehicle front structures. In this study, a finite element (FE) model of THUMS (total human model for safety) was modified in order to assess injuries to a pedestrian lower extremity. Dynamic impact responses of the knee joint of the FE model were validated on the basis of data from the literature. Since in real-world accidents, the vehicle bumper can impact the lower extremities in various situations, the relations between lower extremity injury risk and impact conditions, such as between impact location, angle, and impactor stiffness, were analyzed. The FE simulation demonstrated that the motion of the lower extremity may be classified into a contact effect of the impactor and an inertia effect from a thigh or leg. In the contact phase, the stress of the bone is high in the area contacted by the impactor, which can cause fracture. Thus, in this phase the impactor stiffness affects the fracture risk of bone. In the inertia phase, the behavior of the lower extremity depends on the impact locations and angles, and the knee ligament forces become high according to the lower extremity behavior. The force of the collateral ligament is high compared with other knee ligaments, due to knee valgus motions in vehicle-pedestrian collisions.  相似文献   
278.
279.
Objective: Bicycle riding is increasingly popular in Taiwan, but the number of cyclists injured and cyclists' death rates are both increasing. The aim of this study was to investigate the different characteristics and clinical outcomes of traffic accident–related head injuries among cyclists in urban and rural areas.

Methods: Records of 812 patients (533 urban and 279 rural) admitted to 27 hospitals in Taipei City and Hualien County as the result of a traumatic head injury while bicycling between 1998 and 2013 were retrieved for study. Demographics, details about the accident, protective helmet use, and clinical outcomes were then subjected to analysis.

Results: Urban victims were more likely to be injured during morning and early evening rush hours and rural victims during the day; most urban victims were between 19 and 34 years of age and injured in the slow lane; rural victims tended to be younger or older and were injured in the fast lane (all P ≤.001). Riders who wore a helmet were less likely to suffer loss of consciousness (odds ratio [OR] = 0.31), amnesia (OR = 0.069), neurological disorders (OR = 0.205), or facial fractures (OR = 0.369). Older age, more severe head injuries, and bicycle–motor vehicle collisions influenced the severity of symptoms on admission and the residual effects at discharge.

Conclusions: Differences in the characteristics of injuries in urban and rural areas and the utilization of protective helmets may help government authorities adopt appropriate policies to promote safer and more enjoyable cycling.  相似文献   

280.
Amniocentesis was performed at 17.3 weeks in a pregnancy with severe intrauterine growth retardation. Cytogenetic studies on amniocytes were normal, 46,XX, and the pregnancy was continued. The diagnosis of Smith–Lemli–Opitz syndrome was suspected in the neonatal period and confirmed by the presence of 7-dehydrocholesterol (7-DHC) in the plasma (0.4 mmol/l, normal = not detectable) associated with a low total cholesterol concentration (0.4 mmol/l, normal = 2.56 ± 0.23). Retrospective analysis of the amniotic fluid sample revealed an elevated level of 7-DHC (0.022 mmol/l; normal = undetectable). Therefore measurement of 7-DHC levels in amniotic fluid during the second trimester of pregnancy is useful for the prenatal diagnosis of Smith–Lemli–Opitz syndrome in families at risk and should be considered in cases of severe growth retardation of unknown aetiology for which amniotic fluid is available and in which a normal chromosomal pattern in amniocytes is present.  相似文献   
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