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801.
为了有效提高建筑施工企业现场安全管理的效率,使企业能够明确自身现场安全管理的状况,保证安全管理的有序进行,借鉴项目管理成熟度模型(K-PMMM)和软件成熟度模型(CMM),构建建筑施工企业现场安全管理成熟度评价指标体系。考虑指标之间的关联性和评价过程的模糊性、随机性,同时使调查问卷统计数据的信息量得到充分表达,分别运用测量模型确定评价指标的权重和云模型进行成熟度评价,构建基于测量-云模型(M-CM)的建筑施工企业现场安全管理成熟度评价模型,并利用MATLAB进行仿真分析。将模型应用到实际建筑工程项目中,结果表明,该工程项目的成熟度等级为可管理级,评价结果与现场实际情况相吻合。 相似文献
802.
Joon Seok Kong Oh Hyun Kim Hyun Youk Hee Young Lee Chan Young Kang Sil Sung 《Traffic injury prevention》2018,19(8):S151-S153
AbstractObjective: The purpose of this study is to investigate the injury patterns of noncatastrophic accidents by individual age groups.Methods: Data were collected from the Korean In-Depth Accident Study database based on actual accident investigation. The noncatastrophic criteria were classified according to U.S. experts from the Centers for Disease Control and Prevention’s recommendations for field triage guidelines of high-risk automobile crash criteria by vehicle intrusions more than 12 in. on occupant sites (including the roof) and more than 18 in. on any site. The Abbreviated Injury Scale (AIS) was used to determine injury patterns for each body region. Severely injured patients were classified as Maximum Abbreviated Injury Scale (MAIS) 3 or higher.Results: In this study, the most significant injury regions were the head and neck, extremities, and thorax. In addition, the incidence of severe injury among elderly patients was nearly 1.6 times higher than that of non-elderly patients. According to age group, injured body regions among the elderly were the thorax, head and neck, and extremities, in that order. For the non-elderly groups, these were head and neck, extremities, and thorax. Severe injury rates were slightly different for the elderly group (head and neck, abdomen) and non-elderly group (thorax, head and neck).Conclusions: In both age groups, the rate of severe injury is proportional to an increase in crush extent zone. Front airbag deployment may have a relatively significant relationship to severe injuries. 相似文献
803.
Sang-Keun Song Zang-Ho Shon Yoo-Keun Kim Yoon-Hee Kang In-Bo Oh Chang-Hoon Jung 《Atmospheric environment (Oxford, England : 1994)》2010,44(5):713-723
The influence of ship emissions on ozone (O3) concentrations in a coastal area (CA) including Busan port, Korea was examined based on a numerical modeling approach during a high O3 episode. The analysis was performed by two sets of simulation scenarios: (1) with ship emissions (e.g., TOTAL case) and (2) without ship emissions (e.g., BASE case). A process analysis (PA) (the integrated processes rate (IPR) and integrated reaction rate (IRR) analyses) was used to evaluate the relative contributions of individual physical and chemical processes in O3 production in and around the CA (e.g., sites of Dong Sam (DS) and Dae Yeon (DY)). The model study suggested the possibility that pollutant gases emitted from the ships traversing Busan port can exert a direct impact on the O3 concentration levels in the CA. Largest impacts of ship emissions on the O3 concentrations were predicted at the coast (up to 15 ppb) and at inland locations (about 5 ppb) due to both the photochemical production of pollutant gases emitted from the ships and meteorological conditions. From the PA, the photochemical production of O3 (P(O3)) due to ship emissions in the CA was found to increase by a mean of 1.5 ppb h?1 (especially by ≥10 ppb h?1 at the DS site) during the day. 相似文献
804.
Daiwen Kang Rohit Mathur S. Trivikrama Rao 《Atmospheric environment (Oxford, England : 1994)》2010,44(18):2203-2212
The National Air Quality Forecast Capacity (NAQFC) system, which links NOAA’s North American Mesoscale (NAM) meteorological model with EPA’s Community Multiscale Air Quality (CMAQ) model, provided operational ozone (O3) and experimental fine particular matter (PM2.5) forecasts over the continental United States (CONUS) during 2008. This paper describes the implementation of a real-time Kalman Filter (KF) bias-adjustment technique to improve the accuracy of O3 and PM2.5 forecasts at discrete monitoring locations. The operational surface-level O3 and PM2.5 forecasts from the NAQFC system were post-processed by the KF bias-adjusted technique using near real-time hourly O3 and PM2.5 observations obtained from EPA’s AIRNow measurement network. The KF bias-adjusted forecasts were created daily, providing 24-h hourly bias-adjusted forecasts for O3 and PM2.5 at all AIRNow monitoring sites within the CONUS domain. The bias-adjustment post-processing implemented in this study requires minimal computational cost; requiring less than 10 min of CPU on a single processor Linux machine to generate 24-h hourly bias-adjusted forecasts over the entire CONUS domain.The results show that the real-time KF bias-adjusted forecasts for both O3 and PM2.5 have performed as well as or even better than the previous studies when the same technique was applied to the historical O3 and PM2.5 time series from archived AQF in earlier years. Compared to the raw forecasts, the KF forecasts displayed significant improvement in the daily maximum 8-h O3 and daily mean PM2.5 forecasts in terms of both discrete (i.e., reduced errors, increased correlation coefficients, and index of agreement) and categorical (increased hit rate and decreased false alarm ratio) evaluation metrics at almost all locations during the study period in 2008. 相似文献
805.
中空纤维膜生物反应器处理二甲苯废气 总被引:4,自引:2,他引:2
采用中空纤维膜生物反应器(HFMB)去除气态二甲苯,研究比较了不同进口浓度、停留时间以及悬浮液中生物量对二甲苯净化效果的影响。实验结果表明:随着进口浓度的增加二甲苯净化效率先升高后平稳,生化降解能力(EC)则明显升高;随着停留时间的增加,二甲苯的净化效率明显增加。实验发现最佳的实验条件是:悬浮液循环速率50 L/h,pH值介于6.5到7.5之间,溶解氧6 mg/L左右,停留时间tR=8.8 s;二甲苯的处理效率可达到92%以上。结果还显示二甲苯净化效率随悬浮液循环流速的变化而波动不大,进口二甲苯的组成对净化效率也有一定的影响。与传统的生物法相比,膜生物反应器可以实现气相和液相的分离以及减少占地面积,具有很好的发展前景。 相似文献
806.
Kim KH Mishra VK Kang CH Choi KC Kim YJ Kim DS 《Journal of environmental management》2006,78(2):170-182
The ionic composition of PM2.5 and PM10 was investigated using PM samples collected from Seoul and Busan during the winter of 2002. Based on the measurement data, we attempted to investigate the relative roles of different source processes in the composition of airborne particles at the two distinct urban areas. According to our measurements, the major components of both PM fractions were clearly distinguished from each other at the two different sites. It was found that the ionic concentrations in coarse fractions were generally compatible with each other at the two sites (NH(4)(+), NO(3)(-), NSSS, etc.). However, differences in their concentration levels were significant in the fine fractions and their mass concentration levels in Seoul exhibit threefold enhancement relative to Busan. The results further indicated that anthropogenic signatures were generally more evident in the fine rather than coarse fractions at both sites. However, a comparison of the coarse fraction data indicated the dominance of natural (oceanic) processes at the Busan site and conservative relationships among the different ionic components. The results of the back trajectory analysis confirmed that air mass movement patterns influence the ionic compositions of PM across different particle fractions and between different study sites. 相似文献
807.
808.
可持续发展的理论与宏观调控模式 总被引:8,自引:0,他引:8
从可持续发展观和可持续发展战略出发,分析了传统发展观和发展模式的特点及其主要弊端;进而根据有关国际性文件中的可持续发展概念,给出了中国人易于理解的描述及其基本内涵,强调了人与自然和谐、发展与资源环境相协调是可持续发展的核心,并结合实例阐明了协同学理论是可持续发展的基本理论依据;在分析发展与资源环境相协调的基础条件之后,重点论述了它们之间的协调机制,提出了可持续发展的宏观调控模式。 相似文献
809.
To analyze polycyclic aromatic hydrocarbons (PAHs) at an urban site in Seoul, South Korea, 24-hr ambient air PM2.5 samples were collected during five intensive sampling periods between November 1998 and December 1999. To determine the PAH
size distribution, 3-day size-segregated aerosol samples were also collected in December 1999. Concentrations of the 16 PAHs
in the PM2.5 particles ranged from 3.9 to 119.9 ng m−3 with a mean of 24.3 ng m−3.An exceptionally high concentration of PAHs(∼120 ng m−3) observed during a haze event in December 1999 was likely influenced more by diesel vehicle exhaust than by gasoline exhaust,
as well as air stagnation, as evidenced by the low carbon monoxide/elemental carbon (CO/EC) ratio of 205 found in this study
and results reported by previous studies.
The total PAHs associated with the size-segregated particles showed unimodal distributions. Compared to the unimodal size
distributions of PAHs with modal peaks at < 0.12 μm measured in highway tunnels in Los Angeles (Venkataraman and Friedlander,
1994), four- to six-ring PAHs in our study had unimodal size distributions, peaking at the larger size range of 0.28–0.53
μm, suggesting the coagulation of freshly emitted ultrafine particles during transport to the sampling site. Further, the
fraction of PAHs associated with coarse particles(> 1.8 μm) increased as the molecular weight of the PAHs decreased due to
volatilization of fine particles followed by condensation onto coarse particles. 相似文献
810.