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521.
Ivan W.H. Fung Vivian W.Y. Tam Tommy Y. Lo Lori L.H. Lu 《International Journal of Project Management》2010
Problems on occupational health and safety are commonly occurred in the construction industry, including falling of materials or person from height, stepping on objects and injured by hand tools. Key of dealing with project safety and risk assessment in construction industry is important, thus, way on doing assessment and liability of assessment are necessary for all professionals. However, it is found that those professionals prone to heavily rely on their own experiences and knowledge on decision making on risk assessment, which lack of a systematic approach and lack of ways to check the reliability of the decisions. This paper investigates the need for people involved in construction to take systematic and effective risk assessments for different trades. 14 common types of trades, accidents, and accident causes are explored, in addition to suitable risk assessment methods and criteria. A Risk Assessment Model (RAM) is then developed for assessing risk levels as various project stages with various work trades. A case study is used to prove the workability and reliability of the developed RAM in the practical industry. The developed RAM is found to be benefit for predicting high-risk construction activities and thus preventing accidents occurred based on a set of historical accident data. 相似文献
522.
Barkley Russell A.; Fischer Mariellen; Smallish Lori; Fletcher Kenneth 《Canadian Metallurgical Quarterly》2002,111(2):279
This study examined the persistence of attention-deficit/hyperactivity disorder (ADHD) into young adulthood using hyperactive (N=147) and community control (N=71) children evaluated at ages 19-25 years. ADHD was rare in both groups (5% vs. 0%) based on self-report but was substantially higher using parent reports (46% vs. 1.4%). Using a developmentally referenced criterion (+2 SD), prevalence remained low for self-reports (12% vs. 10%) but rose further for parent reports (66% vs. 8%). Parent reports were more strongly associated with major life activities than were self-reports. Recollections of childhood ADHD showed moderate correlations with actual parent ratings collected in childhood, which suggests some validity for such recollections. The authors conclude that previous follow-up studies that relied on self-reports might have substantially underestimated the persistence of ADHD into adulthood. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
523.
Hydrological drought has wide-ranging impacts on water quality, nutrient and carbon metrics, and given the uncertainty of climate change and the predicted increased frequency and intensity of drought in the future, investigations into changes induced by drought become increasingly important. This study compared physicochemical parameters (temperature, conductivity, pH and DO), nutrients (TN, NOX [NO2 + NO3], NH3 and TP) and carbon (TOC and DOC) between hydrological drought conditions (2006–2008) and hydrological normal conditions (2016–2019) at five sites along the lower Savannah River (Georgia, USA). Although we had predicted that water temperatures would increase from drought, we instead found temperature was significantly lower during drought conditions. Levels of pH and DO were significantly higher during drought. Further, TN, TOC and DOC concentrations were significantly lower during drought, but NOX concentrations were significantly higher during drought. Conductivity varied at the lower river sites, being significantly higher during drought at sites located below the city of Augusta, GA. These complex changes could be attributed to volume reductions coupled with an increase in the percentage of total flow originating from groundwater as well as limnetic reservoir inputs, persistent point source pollution, reduced natural catchment inputs and/or reduced floodplain interactions. The changes that occurred during drought may be disruptive to aquatic life, not only from reduced water quantity but also due to a scarcity of some biologically essential materials and lower food resources, combined with artificially high levels of some other potentially stressful materials. 相似文献