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本文基于国内外油气管道完整性管理(PIM)成果的基础,从数据收集和研究、高后果区分析、完整性评估、管道检测与执行、管道维护修复、效能分析等方面进行具体PIM描述,从体系文件、标准规范、系统平台、支持技术、实施应用五个层面构建PIM管理体系框架。 相似文献
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范例教学法在《SQL Server数据库》教学中的应用 总被引:1,自引:0,他引:1
介绍了范例教学法及其基本原则,选择学生成绩管理系统为教学实例,通过外键约束这一知识点的讲解探讨了范例教学法在该课程教学的应用,在实际教学中取得较好的效果,为其他实践性强的课程教学提供了参考。 相似文献
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H. Jochemsen 《Potato Research》2008,51(1):59-73
Because of objections and worries related to genetically modified organisms (GMOs), the approval of GMO crops is a long and
expensive process. Recently some researchers argued that a specific form of genetic modification, cisgenesis, would be safer
and ethically more acceptable and therefore require a less stringent assessment. In this paper cisgenesis, as defined in recent
literature, is ethically evaluated. After some general remarks on ethics in science and technology, two different basic attitudes
towards reality are sketched as an evaluative framework for interventions in nature. Combined with general characteristics
of biotechnology in agriculture and a view of the role of genetic information in organisms, that framework helps to formulate
an ethical distinction between and evaluation of cisgenesis and transgenesis. It is argued that there is a significant ethical
difference between transgenesis and cisgenesis, but that nevertheless any form of genetic modification should be integrated
in a broader normative understanding of agriculture in order to work towards a more sustainable agriculture.
相似文献
H. JochemsenEmail: |
4.
《Arid Land Research and Management》2013,27(4):389-400
The intent of long-term ecological monitoring is to document changes in important properties of biological communities. At the least, a long-term monitoring system should be designed to detect long-term trends in three key attributes: soil and site stability, hydrologic function, and the biotic integrity of the system. There are four basic guidelines for developing integrated soil-vegetation monitoring systems for rangelands. These are: (1) identifying a suite of indicators which are consistently correlated with the functional status of one or more critical ecosystem processes and/or properties; (2) selecting base indicators on site specific objectives and resource concerns, and inherent soil and site characteristics; (3) using spatial variability in developing and interpreting indicators to make them more representative of ecological processes; and (4) interpreting indicators in the context of an understanding of dynamic, nonlinear ecological processes. To the extent possible, indicators should reflect early changes in ecological processes and indicate that a more significant change is likely to occur. In addition to these guidelines, measurements included in long-term monitoring systems should be rapidly applied, simple to understand, inexpensive to use, and quantitatively repeatable. 相似文献
5.
作为人类灵魂工程师的教师,其职业特殊性决定其更强的社会期望性,决定其应该坚守大义、廉洁自律、公正从教。而高校辅导员与生俱来的政治特性、教师干部双重身份以及“德高为师”的工作特征,决定其应该成为教师行业廉洁从教的标兵。在社会学视角下,运用角色、群体等社会学理论,从个人、群体、社会三维度探析高校辅导员廉洁从教的应然性发现:廉洁从教既是辅导员个体发展的道德内化,又是辅导员职业群体的行业要求,还是社会对辅导员的道德共识。而实现高校辅导员“廉洁从教”主客观相统一、内外部相和谐,关键在于制度约束、道德宣扬、文化建设、社会监督、政策激励等多方并举。 相似文献
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辨析了物质文化遗产、非物质文化遗产的概念,运用大量案例解剖了物质文化遗产中的非物质性和非物质文化遗产中的物质性,并探讨了2种文化遗产之间的区别与联系,进而指出对文化遗产真实性、完整性保护的重要意义。 相似文献
8.
本文从分析稳定与强度,整体性和失稳类别入手,着重讨论了结构稳定的基本概念。对设计者真正处理好稳定问题具有一定的指导意义。 相似文献
9.
浮游生物完整性指数在浙江水源地水质评价中的应用 总被引:5,自引:1,他引:4
2009年9月和2010年8月依次对浙江省4座大中型水库水源地的浮游生物现状进行了调查,采用浮游生物完整性指数(P-IBI)评价方法对数据进行统计分析。经过对22个备选参数的筛选,构建了以藻类密度、藻类平均体重、藻类生物多样性指数、浮游动物/浮游植物、潜在产毒藻类丰度、不可食藻类密度比为入选参数的浮游生物完整性评价体系;进一步利用该评价体系对4座水库的水生态健康程度进行分级评价。结果表明,4座水库的P-IBI评价分值依次为1.216、5.157、3.304和3.542;P-IBI等级依次为差、优、良、良。评价结果能够较好地反映浙江省水源地的富营养化、藻类水华风险程度等水生态健康状况。 相似文献
10.
Harvesting of forests causes a range of disturbances, including changes to hydrology, nutrient inputs, water quality, food sources, habitat structure and channel morphology, which can impact streams over several years and are reflected in changes in community structure. We aimed to determine the relative magnitudes of impact and rates of recovery of benthic macroinvertebrate communities, and associated changes in biotic indices (Quantitative Macroinvertebrate Community Index and an Index of Biotic Integrity), in reaches of different sized streams within progressively logged catchments. We conducted annual summer surveys over seventeen years in fifteen New Zealand streams that differed in size (upstream catchment area between 40 and 2360 ha, mean channel widths between 2.5 and 16 m) and harvest intensity in the surrounding catchment. The largest post-harvest changes in biotic indices and community structures occurred in streams draining relatively small to medium catchments (<500 ha) where >40% of the upstream catchment had been harvested, and particularly after harvesting of overstorey riparian vegetation adjacent to study reaches. The impacts of harvest on invertebrate communities were less evident in wider streams draining catchments over 500 ha, but the largest changes from pre-harvest biotic indices and community structure still generally occurred after harvesting of riparian vegetation along these streams. The changes in community structure after harvesting of riparian vegetation typically included increases in the densities of Diptera, Mollusca and Oligochaetes, and decreases in the densities of Ephemeroptera. These results demonstrate that impacts on benthic macroinvertebrate communities increased as the proportion of upstream catchment harvested increased and/or after riparian vegetation was harvested. Some of the communities in headwater streams had largely recovered towards pre-harvest structures, whereas post-harvest recovery was less evident in relatively large streams, over the duration of the study. 相似文献