基于GB/T 29309标准的HALT测试技术分析

本文以标准GB/T 29309-2012为基础,以某款开关电源为例,对HALT试验设备、工作极限与破坏极限、试验步骤及设备运行中注意点等方面展开介绍,为电子产品可靠性测试提供相关探讨。     

制定粉尘卫生标准的新趋势——介绍欧洲的经验并提出几点建议

介绍了近年来欧洲国家新的粉尘卫生标准及其监测、管理方法,分析其制定粉尘卫生标准的经验,并与我国的粉尘卫生标准情况做了初步的比较,提出了建立我国新分级分类粉尘卫生标准体系的建议。     

Seeing the wood for the trees: the role of woody resources for the construction of gender specific household cultural artefacts in non-traditional communities in the Eastern Cape, South Africa

There is a growing wealth of data capturing the direct-use values of the environment and recognition of forests and wild resources as representing “the poor manȁ9s overcoat”. This focus has however resulted in an emphasis on the utilitarian values of wild resources for rural livelihoods and has for the most part overlooked their cultural values. In tangent to these developments within the field of anthropology there has been increased attention directed towards the relationship between biodiversity and human diversity over the past decade. This has resulted in the recognition of what the Declaration of Belem calls an ȁ8inextricable linkȁ9 between biological and cultural diversity. The term bio-cultural diversity has been introduced as a concept denoting this link. Consequently there is a need for more elaborate assessments of the various ways in which different groups of people find value in biodiversity. The aim of this paper is to demonstrate the cultural significance of wild harvested plant resources for the maintenance of two gender specific cultural artefacts for amaXhosa people in South Africa, to assess the persistence of these practices in rapidly modernizing communities. We demonstrate the endurance of these ancient cultural artefacts in present-day peri-urban communities and suggest that they point to the need for improved understanding of the significance of bio-cultural diversity. The findings of the study should not be interpreted as illustrating stagnation in the traditional past, but rather as pointing at the need for improved understanding of the significance of bio-cultural diversity in a dynamic sense.     

滑坡体三维构造及稳定性分析

采用体元技术建立滑坡体真三维模型,通过基本三棱柱体构建具有复杂曲面结构的空间组合体,每个单元都赋予不同的属性,为滑坡体三维稳定性分析提供基本的前、后处理功能.以此为基础,并结合三维极限平衡分析计算方法,开发了相关的滑坡三维模拟与稳定性分析软件,并成功应用于清江库岸大型滑坡的三维仿真计算.     

基于模糊聚类关联分析法的煤与瓦斯突出程度分析

运用模糊聚类分析方法对煤与瓦斯突出的样本集合进行分类,建立了不同突出程度的模糊模式.用关联分析确定待分析样本与模式的关联程度,以此预测预报样本的煤与瓦斯突出危险程度.实例分析表明,与模糊聚类分类后、将模式与待预报样本组成新样本集合进行聚类分析并以此分类结果进行预报的方法相比,这种预报方法不仅可靠程度高,而且能定量描述待报样本与模式的亲和程度.     

多元可燃性混合气体临界氧浓度的测定

可燃性气体(蒸气)的临界氧浓度目前只限于对单元气体混合物的研究,且影响因素较少提及。通过实验测定了人工煤气、液化石油气的爆炸极限和临界氧浓度,对可燃性气体(蒸气)临界氧浓度的影响因素进行了研究,所测定的数据为煤气、液化石油气的安全防爆工作提供了依据。     

防护鞋靴有害物质限量值研究

本文对防护鞋靴有害物质限量值研究进行了阐述。参考国内外标准,设定防护鞋靴有害物质限制项目和限量值。在检测分析我国具有市场代表性的16个防护鞋靴产品中有害物质含量数据基础上,判断设定限制项目及限量值的可行性。检测结果表明我国防护鞋靴生产技术水平基本能够达到限量要求,设定的限量值可以作为制定国家标准的参考依据。     

天津市土壤元素背景值的地域差异及成因分析

论述了天津土壤中Cu,Pb等13种微量元素背景值在行政区，土壤类型中的差异规律，并分析了引起元素背景值地域差异的原因。     

人地协同论：可持续发展模型构建的基础

人地协同论是在陆地系统科学、非线性系统理论基础上建立起来的关于可持续发展的一个数理模型,它以社会与自然的交互作用、交界面性质及其演化规律为研究对象。本文根据系统生态学理论,提出了关于可持续生存的数学定义。     

Criteria for the evaluation of dioxins in the environment

In FRG and other countries unequivocal criteria for the limitation of dioxins (PCDD's/PCDF's) in food like vegetables and fruits are lacking. These have to be directly associated with the limitation of dioxins in the soil and the deposition of particulate matter as the two main pathways for plant contamination. Based on recent investigations in the vicinity of cable-waste incinerators in Northrhine-Westphalia with comparatively high contents of dioxins in garden plants and soils and other sources of dioxins, considerations are given for the establishment of the criteria urgently needed.