Policy challenges and approaches for the conservation of mangrove forests in Southeast Asia

Many drivers of mangrove forest loss operate over large scales and are most effectively addressed by policy interventions. However, conflicting or unclear policy objectives exist at multiple tiers of government, resulting in contradictory management decisions. To address this, we considered four approaches that are being used increasingly or could be deployed in Southeast Asia to ensure sustainable livelihoods and biodiversity conservation. First, a stronger incorporation of mangroves into marine protected areas (that currently focus largely on reefs and fisheries) could resolve some policy conflicts and ensure that mangroves do not fall through a policy gap. Second, examples of community and government comanagement exist, but achieving comanagement at scale will be important in reconciling stakeholders and addressing conflicting policy objectives. Third, private‐sector initiatives could protect mangroves through existing and novel mechanisms in degraded areas and areas under future threat. Finally, payments for ecosystem services (PES) hold great promise for mangrove conservation, with carbon PES schemes (known as blue carbon) attracting attention. Although barriers remain to the implementation of PES, the potential to implement them at multiple scales exists. Closing the gap between mangrove conservation policies and action is crucial to the improved protection and management of this imperiled coastal ecosystem and to the livelihoods that depend on them.     

A new approach to quantitative assessment of reliability of passive systems

The objective of this paper is to show how probabilistic reliability can be assessed for complex systems in the absence of statistical data on their operating experience, based on performance evaluation of the dominant underlying physical processes. The approach is to distinguish between functional and performance probabilities when dealing with the quantification of the overall probability of a system to perform a given function in a given period of time (reliability). In the case of systems where sufficient statistical operating experience data are available, one can focus the quantitative evaluation entirely on the assessment of the functional probability for a given active item (e.g. a pump) by assuming that the specification, layout, construction and installation is such that the item is providing the assigned performance, e.g. in the form of generating the required flow rate. This is how traditional probabilistic safety assessments (PSAs) focus the reliability analysis for the various safety features on the calculation of values for the availability per demand. In contrast, for various systems relevant in advanced technical applications, such as passive safety features in innovative reactor designs, it is essential to evaluate both functional and performance probabilities explicitly and combine the two probabilities later on. This is of course due to the strong reliance of passive safety systems on inherent physical principles. In practice, this means that, for example, in case of a passive cooling system based on natural circulation of a given medium, one has to evaluate and to assess the probability to have a medium condition and a flow rate such that a cladding temperature, represented by a probability distribution, can be hold at a required level. A practical example of this method is given for the case of the reliability assessment of a residual passive heat removal system. General conclusions are drawn regarding reliability estimation of complex, interconnected systems in the absence of statistical performance data, such as for infrastructures.     

Enriching blast furnace gas by removing carbon dioxide

Blast furnace gas (BF gas) produced in the iron making process is an essential energy resource for a steel making work. As compared with coke oven gas, the caloric value of BF gas is too low to be used alone as fuel in hot stove because of its high concentrations of carbon dioxide and nitrogen. If the carbon dioxide in BF gas could be captured efficiently, it would meet the increasing need of high caloric BF gas, and develop methods to reusing and/or recycling the separated carbon dioxide further. Focused on this, investigations were done with simple evaluation on possible methods of removing carbon dioxide from BF gas and basic experiments on carbon dioxide capture by chemical absorption. The experimental results showed that in 100 minutes, the maximum absorbed doses of carbon dioxide reached 20 g/100 g with ionic liquid as absorbent.     

惯性约束聚变设施设计建造中的安全性工作

国家点火设施是隶属美国能源部的一座惯性约束激光聚变设施 ,目前正在美国劳伦斯里弗摩尔国家实验室进行建造。描述了其在设计和建造中的安全性工作过程     

基于模糊网络和时间依赖的应急车辆调度优化研究

突发灾害的应急物资调度是减轻人民财产损失、防止次生灾害发生、保障社会稳定的必要支撑。借助模糊数学中的三角模糊数学方法对不确定的需求信息特征进行描述,用模糊函数积分确定车辆在路段的模糊行驶时间。以应急车辆调度的总时间最短为调度的主要目标,同时配送数量应最大限度地满足需求点的需求量为次要目标建立应急车辆调度模型。然后设计粒子群算法对模型进行求解。最后通过算例,验证建立的模型拟合现实中的情况,结果不是确定数值,而是模糊数值范围的优化。     

新型絮凝剂的制备与应用

选用花岗闪长岩为原料 ,通过一系列的化学熔融聚合反应制成新型絮凝剂———聚硅酸铁铝盐絮凝剂。试验室和生产应用试验结果表明 ,该絮凝剂成本低 ,效果好 ,皮革废液经处理出水水质达到污水综合排放标准 (GB8978-1 996)。     

Enriching blast furnace gas by removing carbon dioxide

Blast furnace gas (BF gas) produced in the iron making process is an essential energy resource for a steel making work. As compared with coke oven gas, the caloric value of BF gas is too low to be used alone as fuel in hot stove because of its high concentrations of carbon dioxide and nitrogen. If the carbon dioxide in BF gas could be captured efficiently, it would meet the increasing need of high caloric BF gas, and develop methods to reusing and/or recycling the separated carbon dioxide further. Focused on this, investigations were done with simple evaluation on possible methods of removing carbon dioxide from BF gas and basic experiments on carbon dioxide capture by chemical absorption. The experimental results showed that in 100 minutes, the maximum absorbed doses of carbon dioxide reached 20 g/100 g with ionic liquid as absorbent.     

Root causes of hydrocarbon leaks on offshore petroleum installations

Hydrocarbon leaks on offshore installations may result in severe consequences to personnel, to the environment and to assets. In order to prevent such leaks, it is crucial to understand their root causes. The objective of this paper is to study the circumstances of hydrocarbon leaks on the Norwegian continental shelf (NCS). In the study, all reported hydrocarbon leaks from process inventories on all offshore installations on the NCS, with an initial leak rate higher than 0.1 kg/s in the period 2008–2014, have been considered. This includes 78 hydrocarbon leaks, of which about 60% have occurred during manual intervention on normally pressurized systems. The dominating activity when leaks occur is preventive maintenance. A significant fraction of the leaks occur during the preparation for maintenance; such a preparation is typically carried out during the night shift. About half of the leaks are associated with wellhead area and manifolds, separation and compression systems. A substantial fraction of the leaks can be associated with verification faults, dominated by the failure to comply with procedural requirements that are needed to carry out independent verification.     

人的失误理论研究进展

人的失误理论研究已进入结合认知心理学并以人的失误动态过程为研究热点的阶段。笔者回顾了人的失误理论研究的进展,讨论了相关的人的认知行为类型、认知失误的基本概念和人的失误模型。例如适用于不同情景和应用条件的几种模型:刺激-调制-响应(S-O-R)模型;失误的决策阶梯(Step-ladder)模型;通用GEMS模型以及Worledge认知模型。由于人的行为的复杂性和难以预测性造成了人的可靠性分析(HRA)的困难,因此,对人的行为的深入了解必须从人的行为特性及其规律性入手,将人的可靠性分析与行为科学理论结合起来,揭示人的失误发生的内在规律。与此同时,重点分析了概率安全评价技术(PSA)中如何对人的失误事件进行定量估计;如何考虑人的心理因素影响的几种重要的人的失误理论模型,并对今后这该领域中的研究方向进行了讨论。     

PSA application for a PCB detoxification plant

 Polychlorinated biphenyls (PCBs), a type of persistent organic pollutants (POPs), are considered to be endocrine disrupters. According to the Stockholm Convention on POPs, PCB detoxification is being accelerated globally. We have developed an environmentally sound chemical PCB detoxification plant using the ultraviolet ray/catalyst method. The purpose of this paper is to check the design methodology for the PCB detoxification plant by the application of probabilistic safety analysis. First, possible hazardous events were determined; second, the weakest points in these hazardous events were established; and third, the impact when failures arise at the weak points in the system were studied. We clarified the preventive measures as follows. To prevent PCBs leaking into the environment, select leak-tight valves for the piping containing PCBs, and reduce the number of valves. To prevent fire or explosions due to leaks of an inflammable mixture, select leak-tight valves, reduce the number of valves installed in the piping, and improve the reliability of the suppression tank in the isopropyl alcohol (IPA) recovery unit. Received: February 27, 2001 / Accepted: June 17, 2002