高压XLPE电缆缓冲层烧蚀故障机理分析与结构优化

高压交联聚乙烯(cross-linked polyethylene,XLPE)电缆缓冲层烧蚀故障频发,在行业内引起广泛关注。电缆结构优化有利于解决放电烧蚀问题,文中从缓冲层放电灼伤机理角度出发,建立电缆有限元模型进行电场仿真,分析讨论不同结构参数下气隙电场分布的变化,并开展模拟试验对结构优化方案进行研究。结果表明：在满足电缆设计要求的前提下,减小缓冲层厚度、减小轧纹深度、增加金属套和缓冲层的挤压深度有利于减弱接触不良导致的气隙电场畸变;平滑铝套结构与缓冲层的接触电阻较小,在抑制缓冲层放电烧蚀故障方面具有优势。     

计算机控制系统在热水蒸汽锅炉改造中的应用

本文应用了先进的工业PC控制机,实现了对中小型燃煤热水蒸汽锅炉的自动控制设计和改造。系统包括:水位控制、炉压控制、燃烧控制、事故监控等控制环节,提出了模糊控制模型。使工业热水蒸汽锅炉系统具有抗干扰能力强,运行安全稳定,使用简便,经济节能,自动化控制程度高,适应性强等优势。改造后的系统可使燃料燃烧充分,降低污染,提高了蒸汽质量。     

A simulation analysis of the detectability of understory burns in miombo woodlands

The miombo woodlands of southern Africa are one of the most extensively burned biomes in the tropics. The detectability of understory burns in these woodlands was assessed with a sensitivity analysis approach, based on a hybrid geometrical-optical radiative transfer model. Model input data were obtained from a variety of sources, including field biometry and spectroradiometry, and satellite data. The effects of variable tree percent cover, leaf area index, stand density, burn scar age, illumination and observation geometry, and spectral region, were taken into account. Detectability of understory burns was defined as the spectral separability of burned and unburned understory, measured with the Jeffries-Matusita distance, for all possible combinations of the green, red, and near-infrared channels of the Moderate Resolution Imaging Spectrometer (MODIS) sensor. Single channels, or pairwise combinations of channels perform poorly at detecting understory burns, but a large improvement in detectability is obtained for the combination of the three spectral domains. The detectability of understory burns is largely insensitive to the effects of stand structure and illumination/observation geometry, and depends primarily on burn scar age. Our results agree with those of previous satellite-based studies of burns scar detectability in African savanna woodlands.     

Transforming Growth Factor-Beta in Skeletal Muscle Wasting

Transforming growth factor-beta (TGF-β) is part of a family of molecules that is present in many body tissues and performs many different functions. Evidence has been obtained from mice and human cancer patients with bony metastases and non-metastatic disease, as well as pediatric burn patients, that inflammation leads to bone resorption and release of TGF-β from the bone matrix with paracrine effects on muscle protein balance, possibly mediated by the generation of reactive oxygen species. Whether immobilization, which confounds the etiology of bone resorption in burn injury, also leads to the release of TGF-β from bone contributing to muscle wasting in other conditions is unclear. The use of anti-resorptive therapy in both metastatic cancer patients and pediatric burn patients has been successful in the prevention of muscle wasting, thereby creating an additional therapeutic niche for this class of drugs. The liberation of TGF-β may be one way in which bone helps to control muscle mass, but further investigation will be necessary to assess whether the rate of bone resorption is the determining factor for the release of TGF-β. Moreover, whether different resorptive conditions, such as immobilization and hyperparathyroidism, also involve TGF-β release in the pathogenesis of muscle wasting needs to be investigated.     

An intervention to reduce kerosene-related burns and poisonings in low-income South African communities.

Objective: Unintentional injury rates in low- and middle-income countries are up to 50 times higher than high-income nations. In South Africa, kerosene (paraffin) is a leading cause of poisoning and burns, particularly in low-income communities where it serves as a primary fuel for light, cooking, and heating. This study tested a community-based intervention to reduce kerosene-related injury risk. The intervention used a train-the-trainers model, whereby expert trainers train local paraprofessionals, who in turn deliver educational materials to community residents. The intervention was theory-driven, pragmatically motivated, and culturally sensitive. Design: Prospective quasi-experimental intervention design with nonequivalent case versus control groups. Main Outcome Measures: Three primary outcome measures were considered: self-reported knowledge of kerosene safety, observed practice of safe kerosene use, and self-reported recognition of risk for kerosene-related injury. Results: ANOVA models suggest a large and significant increase in self-reported kerosene-related knowledge in the intervention community compared to the control community. There were smaller, but statistically significant changes, in kerosene-related safety practices and recognition of kerosene injury risk in the intervention community compared to the control community. Conclusion: The intervention was successful. A train-the-trainers model might be an effective educational tool to reduce kerosene-related injury risk in low-income communities within low- and middle-income countries. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

液化天然气工厂可能出现的人身伤害及防治措施

液化天然气工厂作为生产LNG的装置,其操作人员要面临LNG的低温特性及天然气———空气混合物的可燃性可能带来的人身伤害。针对这些可能出现的人身伤害做了讨论,并提出相应的防治措施。     

The reliability and validity of the Perceived Stigmatization Questionnaire (PSQ) and the Social Comfort Questionnaire (SCQ) among an adult burn survivor sample.

In this study, 361 adult burn survivors completed the Perceived Stigmatization Questionnaire (PSQ), the Social Comfort Questionnaire (SCQ), and other measures. Both the PSQ and SCQ had good internal consistency indices. Factor analysis of the PSQ yielded 3 factors (absence of friendly behavior, confused/staring behavior, and hostile behavior). The SCQ had 1 factor. Conjoint factor analysis with measures of related constructs (body esteem, body-esteem importance, depression, social support) suggested that PSQ and SCQ measure distinct constructs. Correlations with the related psychosocial constructs and burn characteristics suggested the PSQ and SCQ have good convergent and discriminant validity. Limitations of the study are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

热防护服装热湿传递模型研究及发展趋势

 合理地评价热防护服装的热防护性能对减少消防员的皮肤烧伤具有重要的意义。本文主要回顾并评价了热防护服装的热湿传递模型国内外的研究现状,包括皮肤传热模型及其烧伤评价模型、单层或多层面料的一维和二维热湿传递以及整体服装的三维热湿传递模型等,并比较分析了这些模型的应用缺陷,预测了热防护服装热湿传递模型研究未来的发展趋势。热湿传递模型的研究不仅可以为热防护服装的使用提供科学的理论指导以减少皮肤烧伤或蒸汽烧伤,而且能够进一步推动服装热防护性能测试技术的发展,满足我国“安全发展”和“公共安全防治”的技术需要。