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排序方式: 共有496条查询结果,搜索用时 31 毫秒
1.
William M. Pitts Martin Werrel Marco Fernandez Mary A. Long Evan A. Eisenberg James Filliben Cory D. Runyon 《火与材料》2021,45(1):127-154
Fire spread and growth on real‐scale four cushion mock‐ups of residential upholstered furniture (RUF) were investigated with the goal of identifying whether changes in five classes of materials (barrier, flexible polyurethane foam, polyester fiber wrap, upholstery fabric, and sewing thread), referred to as factors, resulted in statistically significant changes in burning behavior. A fractional factorial experimental design plus practical considerations yielded a test matrix with 20 material combinations. Experiments were repeated a minimum of two times. Measurements included fire spread rates derived from video recordings and heat release rates (HRRs). A total of 13 experimental parameters (3 based on the videos and 10 on the HRR results), referred to as responses, characterized the measurements. Statistical analyses based on Main Effects Plots (main effects) and Block Plots (main effects and factor interactions) were used. The results showed that three of the factors resulted in statistically significant effects on varying numbers of the 13 responses. The Barrier and Fabric factors had the strongest main effects with roughly comparable magnitudes. Foam was statistically significant for fewer of the responses and its overall strength was weaker than for Barrier and Fabric. No statistically significant main effects were identified for Wrap or Thread. Multiple two‐term interactions between factors were identified as being statistically significant. The Barrier*Fabric interaction resulted in the highest number of and strongest statistically significant effects. The existence of two‐term interactions means that it will be necessary to consider their effects in approaches designed to predict the burning behavior of RUF. 相似文献
2.
建造以乡土植物为主体的园林绿地 总被引:31,自引:2,他引:31
指出外来植物扰乱生态平衡、破坏自然环境与人文景观以及对人们生活的严重影响等各种弊端,对园林绿化的现状以及方式方法进行了反思,提出以乡土植物为主体的园林绿地建设是城市园林绿化的惟一出路.最后,指出在进行以乡土植物为主体的城市园林绿地建设过程中存在的问题及解决办法. 相似文献
3.
再生水灌溉城市园林绿地对植物矿质元素和土壤性状的影响研究 总被引:2,自引:0,他引:2
采用示范区绿地调查的方法,研究了再生水灌溉对北京地区有代表性的园林植物生长状况的影响,并采集植物叶片和立地土壤进行相关指标的化验分析。结果表明,再生水灌溉区植物生长良好,叶色正常,试验期内大部分植物外观未见有明显异常现象;叶片矿质元素总体上表现出升高的趋势;银杏、油松、连翘、紫薇、榆叶梅、玉兰、栾树等植株叶片内钠元素含量增加,钾元素含量则有所下降;叶片矿质元素含量均在正常范围内;土壤中全盐量、水溶性钠、交换态钠和氯化物均表现出升高趋势,但目前尚未达到盐害水平。最后对加强再生水在园林中的应用提出了几条建议。 相似文献
4.
Media as Educator,Media as Disruptor: Conceptualizing the Role of Social Context in Media Effects 下载免费PDF全文
We document how social contexts serve to refract media effects. We theorized the relationship between media use and individual‐level knowledge (and attitude) would be stronger when community‐level knowledge (and attitude) was low than when it was high. Data come from a national survey (N = 12,608 women and 1,237 men) conducted in Nepal. Knowledge and stigma toward people living with HIV were the 2 dependent variables. Hypotheses were tested 12 times: across the use of 3 media (newspaper, radio, television) × 2 study outcomes (knowledge and attitudes) × 2 genders. Predicted interactions were supported in 9 of the 12 tests. Findings point to the need to take into account the role of community factors in theorizing about media effects. 相似文献
5.
Beyond Cognitive Framing Processes: Anger Mediates the Effects of Responsibility Framing on the Preference for Punitive Measures 下载免费PDF全文
A new stream of research indicates that framing effects are based on emotional as well as cognitive processes. However, it is not entirely clear whether emotions mediate framing effects and what the moderators of emotional mediation processes are. To address these questions, we conducted an experiment in which the framing of responsibility for a social problem was manipulated (ambivalent vs. high‐responsibility frame). We find that the high‐responsibility frame increased the preference for punitive measures by increasing responsibility beliefs and eliciting anger. Furthermore, we find that trait anger moderates the framing effect on anger and that responsibility beliefs are positively associated with anger intensity. The significance of these findings for framing research and suggestions for future studies are discussed. 相似文献
6.
Using Fuzzy Cost‐Based FMEA,GRA and Profitability Theory for Minimizing Failures at a Healthcare Diagnosis Service 下载免费PDF全文
Samira Abbasgholizadeh Rahimi Afshin Jamshidi Daoud Ait‐Kadi Angel Ruiz 《Quality and Reliability Engineering International》2015,31(4):601-615
This paper proposes an integrated approach to identify, evaluate and improve the potential failures in a service setting. This integrated approach combines Fuzzy cost‐based service‐specific FMEA (FCS‐FMEA), Grey Relational Analysis (GRA) and profitability theory for better prioritization of the service failures by considering cost as an important issue and using the profitability theory in a way that the corrective actions costs are taken into account. Considering profitability with FCS‐FMEA and GRA reduces the losses caused by failure occurrence. Besides, a maximization linear mathematical problem is used to select the best mix of failures to be repaired. We apply our approach to an academic example concerning the potential failures diagnosis of the Internal Medicine service of a hospital located in Seoul, Korea. We applied our approach and solved the associated maximization problem by a commercial solver, producing an optimal solution which indicates the most convenient mix of failures to be repaired by considering available budget. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
7.
This paper explores the public's understanding of 'sustainable energy', focusing upon hydrogen, which for most is unfamiliar. We report reactions to a first tour of the recently established 'Hydrogen Research and Demonstration Centre' in the Valleys of South Wales, which was guided by its scientists and engineers. The visitors lived within 50 miles and fell into three age-categories: 14-year old Baccalaureate students; 18–19 year old students at Tertiary College; and adult- members of a Citizens' Panel. They took part in six focus groups which were facilitated, recorded and then analysed thematically by independent sociologists. The paper examines themes on which the groups agreed or disagreed, and how clear or ambiguous their discourse was. While broad consensus was reached on benefits, costs and safety of hydrogen, there were differences in how groups imagined incorporating it into their lives. In conclusion, we draw lessons for securing wider public commitment to sustainable energy. 相似文献
8.
Effects of strain on the corrosion behaviour of X80 steel 总被引:1,自引:0,他引:1
The effects of strain on the corrosion behaviour of X80 steel in 0.62 M NaCl aqueous solution were investigated in the present paper. An increase in strain causes the corrosion resistance of the specimen to present a down and up trend, with the lowest point at about 1.0 × 10−3. When the strain increases further, corrosion resistance decreases again until the strain reaches 5.5 × 10−3. After that, corrosion resistance improves with the increase in strain and tends to be relatively stable. The variation of corrosion resistance has much to do with the surface activity and behaviour of dislocation on the surface of the specimen. 相似文献
9.
Hydrogen solubility and diffusivity of Fe–Cr–Ni austenitic stainless steels were measured through exposure to gaseous hydrogen at a pressure of 10 MPa over the temperature range 110–235 °C. The hydrogen solubility depended on the alloy compositions, whereas the diffusion coefficients were nearly identical at a given temperature. Hydrogen uptake in the stable austenitic steels by exposure to high-pressure gaseous hydrogen led to some loss of ductility, while their fracture surfaces showed evidence of plastic deformation. This was attributed to the enhanced inhomogeneity of plastic deformation in the presence of hydrogen and the increased stress for plastic instability with increasing hydrogen concentration. 相似文献
10.
目的 探讨比较强化降脂与介入治疗治疗在冠心病二级预防中的效果。方法 选取2009年1月至2010年1月于我院进行治疗的120例冠心病患者为研究对象,将其随机分为A组(强化降脂组)60例和B组(介入治疗组)60例,后将2组患者的心肌梗死发生率、心绞痛发生率、再次住院率及治疗前及治疗后1个月及3个月的血脂、血清hs-CRP、UA水平进行检测及比较。结果 经研究比较发现,A组的心肌梗死发生率、心绞痛发生率、再次住院率均低于B组,A组治疗后1个月及3个月的血清TG、TC及LDL-C、hs-CRP、UA水平均明显低于B组,而血清HDL-C的水平则高于B组,P均<0.05,均有显著性差异。结论 强化降脂治疗在冠心病二级预防中的效果较好,值得临床推广及应用。 相似文献