我国生态环境监测网络建设成效与展望

2015年中央全面深化改革领导小组审议通过《生态环境监测网络建设方案》,推动全国生态环境监测网络建设取得重大成就.对照《生态环境监测网络建设方案》提出的"全面设点,完善生态环境监测网络"方面的任务与要求,对生态环境监测网络建设成效进行客观评估,并对生态环境监测面临的形势与不足进行了深入剖析.针对加强生态环境监测网络建设...     

Internal corrosion hazard assessment of oil & gas pipelines using Bayesian belief network model

A substantial amount of oil & gas products are transported and distributed via pipelines, which can stretch for thousands of kilometers. In British Columbia (BC), Canada, alone there are over 40,000 km of pipelines currently being operated. Because of the adverse environmental impact, public outrage and significant financial losses, the integrity of the pipelines is essential. More than 37 pipe failures per year occur in BC causing liquid spills and gas releases, damaging both property and environment. BC oil & gas commission (BCOGS) has indicated metal loss due to internal corrosion as one of the primary causes of these failures. Therefore, it is of a paramount importance to timely identify pipelines subjected to severe internal corrosion in order to improve corrosion mitigation and pipeline maintenance strategies, thus minimizing the likelihood of failure. To accomplish this task, this paper presents a Bayesian belief network (BBN)-based probabilistic internal corrosion hazard assessment approach for oil & gas pipelines. A cause-effect BBN model has been developed by considering various information, such as analytical corrosion models, expert knowledge and published literature. Multiple corrosion models and failure pressure models have been incorporated into a single flexible network to estimate corrosion defects and associated probability of failure (PoF). This paper also explores the influence of fluid composition and operating conditions on the corrosion rate and PoF. To demonstrate the application of the BBN model, a case study of the Northeastern BC oil & gas pipeline infrastructure is presented. Based on the pipeline's mechanical characteristics and operating conditions, spatial and probabilistic distributions of corrosion defect and PoF have been obtained and visualized with the aid of the Geographic Information System (GIS). The developed BBN model can identify vulnerable pipeline sections and rank them accordingly to enhance the informed decision-making process.     

A neuro-fuzzy algorithm for assessment of health,safety, environment and ergonomics in a large petrochemical plant

Process plants such as petrochemical units have been continuously trying to improve Health, Safety, Environment and Ergonomics (HSEE) programs. This study proposes an adaptive network-based fuzzy inference system (ANFIS) for assessment of HSEE programs in a petrochemical plant. The proposed neuro-fuzzy approach is applied to a set of operators in the petrochemical unit to show its applicability and superiority. To achieve the objectives of this study, standard questionnaires with respect to HSEE are completed by operators. The average results for each category of HSEE are used as inputs and accomplishment of HSEE programs is used as output for the algorithm. Moreover, this algorithm is used to rank operators performance with respect to HSEE. Finally, the algorithm identifies efficient operators with respect to HSEE. This is the first study that introduces an intelligence algorithm for assessment and improvement of HSEE program in a petrochemical plant.     

非线性理论在开采沉陷中的应用

简要介绍了近年来把非线性理论应用于矿山开采沉陷领域的一些研究成果,主要包括两大部分：（１）神经网络理论在开采沉陷中的应用;（２）离散单元法在开采沉陷中的应用     

大气环境质量综合评价的B－P网络模型

选取大气环境质量的三级标准作为３个学习样本，以ＳＯ＿２，ＮＯ＿ｘ和ＴＳＰ三种污染物的三级标准浓度限值作为样本的输入特征值，建立了三参数的Ｂ－Ｐ网络大气环境质量综合评价模型，用该模型对３１个测点的大气环境质量进行评价，并与模糊数学和灰色系统法的评价结果比较，表明Ｂ－Ｐ网络用于大气环境质量评价具有优越性。     

网络有效性:评价旅游活动对环境影响的一个新指标

旅游会给环境带来一定的负面影响,而旅游区的游径往往是这种影响的集中体现地。游径的构建方式、空间格局在很大程度上决定了旅游对环境的影响程度。但目前景观生态学中相关的廊道指标不能对此做出有效的评价。论文以九寨沟国家级自然保护区为案例研究地,克服现有廊道指标只单一考虑空间特性的局限,将廊道的空间格局与生态功能结合起来,采用运筹学的方法,提出网络有效性这个新的指标。在九寨沟案例研究地的应用表明,与传统景观生态学指标连通度和环通度相比,网络有效性指标能够直观地反映游径的利用状况,也能够较好地反映旅游的环境影响程度,从而为旅游管理提供依据。     

我校图书馆自动化建设的实践与思考

本文简述了我校图书馆自动化建设的历史进程，分析了图书馆自动化建设的现状、达到的效果和尚存在的问题，并针对这些问题，提出了相应的改进措施。     

北京市数字遥测地震台网技术系统

地球科学是一门观测科学,地震观测是研究与应用工作的基础。因此,布设科学合理、运行稳定可靠的观测台网,可更好地为地震监测预报、地震应急以及科学研究提供保障。本文较系统的介绍了北京市数字遥测地震台网,并就系统建设过程中的一些技术问题进行了论述。     

真空排污系统管网的铺设

污水在压差的作用下 ,向前运动一段时间后 ,回落到各提升段的低洼处 ,所引起的激励波继续向前传播 ,激发前方静止的污水再次运动起来。这样经多次提升 ,污水越过上坡进入收集罐。由于只考虑向下坡度小于 2 %的管线的摩擦损失及各提升段的静压头损失 ,因此 ,根据不同的系统运行水平 ,污水提升高度可达 4.5～ 6m ,输送距离可达4km。     

人工神经网络模型在石油资源预测中的应用

锦270井区大凌河油层是盆地大幅度沉降条件下的产物，以深陷湖环境为主，发育湖底扇浊积岩。准确预测大凌河油层的砂体分布和泥质含量，是勘探目标选择的关键。由于钻井资料少，不能反映储层横向变化。为了准确预测储层的横向变化，综合钻井地质资料和地震勘探资料，并为了反映地震资料的多个参数与储层横向变化间的非线性相关关系，采用人工神经网络模型进行预测，计算了大凌河油层砂层厚度和泥质含量的平面分布。依据计算结果，分析了有利油气区的分布，并给出了几点结论。