海上采油油轮增设油气分离装置的探讨

胜利油田海上边际油井受环境条件的制约,安装采油的油气分离装置也较简单;由此产出的原油中含有20%天然气进入油轮,给整个采油的油轮带来危险并给操作人员带来危害。在采油油轮上增设油气处理装置后,既改善了油轮操作人员的工作环境,消除了油轮事故隐患,又节约了在原平台上增设油气分离设施的费用,保护了采油油轮操作者的安全与健康,保障了安全生产。笔者依据胜利油田海上采油油轮的生产作业状况,论述在采油油轮上增设油气分离装置的必要性,并对所增设的设备及施工条件作了初步探讨。同时还论证了海上采油油轮增设油气分离装置,是改善操作人员的工作环境和消除事故隐患的必要措施。     

Accurate power-sharing,voltage regulation,and SOC regulation for LVDC microgrid with hybrid energy storage system using artificial neural network

ABSTRACT

In this paper, an artificial neural network-based control strategy is proposed for low voltage DC microgrid (LVDC microgrid) with a hybrid energy storage system (HESS) to improve power-sharing between battery and supercapacitor (SC) to suit the demand-generation imbalance, maintain state-of-charge (SOC) within boundaries and thereby to regulate the dc bus voltage. The conventional controller cannot track the SCs current rapidly with the high-frequency component that will place dynamic stress on the battery, further resulting in shorter battery life. The significant advantage is that in the proposed control strategy, redirections of unwaged battery currents to SCs for fast compensations enhance battery life span. The proposed control strategy effectiveness was investigated by simulations, including a comparison of overshoot/undershoot and settling time in dc bus voltage with a conventional control strategy. The results have been experimentally verified by hardware-in-loop (HIL) on a field-programmable gate array (FPGA)-based real-time simulator.     

CRITICAL STATE OF SALT-WATER UPCONING BENEATH ARTESIAN DISCHARGE WELLS1

ABSTRACT: An approach, based on the realization of the vertical components of flow is presented to determine the free surface of gravity wells and the shape of salt-water upconing in artesian aquifers. The transitional stages from pumping fresh water to pumping salt water at the critical condition are discussed. Vertical hydraulic resistances, being determined and included in the flow domain, allow the use of the finite-difference approximation in a simple form. The suggested approach implies the use of either simple modeling or computing techniques.     

复杂矿井通风系统分支阻力可调性数值研究

笔者应用数字实验方法 ,通过调节分支阻力 ,研究它对通风系统的影响。研究结果表明 :当一些分支的阻力调到接近完全隔断风流的极大值时 ,网络分析结果仍然正常 ,不影响迭代技术 ;同样也说明了分支阻力预先输入的可行性 ;各分支阻力的变化对通风系统的影响程度是不一样的 ,这由分支在通风网络中的位置决定 ;通过分析 ,给出了通风系统中两风机的相互影响的情况。     

局域网内ARP协议攻击及解决办法

地址解析协议(ARP,Address Resolution Protocol)是用于关联某个3层(网络层)地址(如IP地址)和某个两层(数据链路层)地址(MAC地址)。由于ARP协议的自身的缺陷,使得ARP协议在使用的过程中存在着盗用IP地址和ARP欺骗等严重的安全问题。笔者在对ARP协议简要介绍的基础上,主要分析了利用ARP协议漏洞进行网络攻击的原理和攻击的常见方式,并提出相关的ARP攻击的解决办法。     

基于贝叶斯网络分类的土壤盐渍化遥感监测

贝叶斯网络是一种将贝叶斯概率方法和有向无环图的网络拓扑结构有机结合的概率模型.采用贝叶斯网络分类对具有典型干旱特征的库车县土壤盐渍化情况进行监测,首先应用条件独立性测试原理建立贝叶斯网络结构,把研究区遥感数据进行离散化,然后应用贝叶斯定理作为分类原则,将每个像元分为像元最大概率的类别.研究结果表明该方法来分类6种地类的整体分类精度达到96%,并为该区盐渍地面积,空间分布等特征监测提供较好的依据.     

太湖叶绿素a浓度预测模型初探

以太湖2005年的监测资料为基础,运用多元统计回归和BP人工神经网络方法构建模型,探求叶绿素a与水深、水温、营养盐等10项环境因子之间的关系,通过验证发现BP模型对叶绿素a浓度的拟合值与叶绿素a浓度的实测值之间的均方误差为220．3059,优于统计回归模型的235．4569;此外对两种模型进行了灵敏度测试,结果都显示总磷不是太湖叶绿素a浓度的限制因子,而水深、水温、总氮的变化对叶绿素a浓度影响显著。本研究对太湖叶绿素a浓度预测模型的建立是十分有意义的。     

Advancing the climate regime through linking domestic emission trading systems?

More and more countries are incorporating the instrument of emissions trading into their national climate policies. This emerging mosaic of emissions trading schemes (ETS) raises the question of whether they should be linked with each other. From an economic point of view, linking of domestic schemes is supposed to increase the economic efficiency of carbon markets. In addition, linking is also expected by some to yield substantial political benefits in terms of the evolution of the UNFCCC/Kyoto regime. However, these optimistic prospects are based on a best-case scenario where all major countries establish environmentally effective emissions trading systems and then link them with each other. Real-life politics might develop rather differently. This paper therefore examines to what extent the current status of emissions trading in industrialised countries provides a basis for reinforcing and moving forward the international climate regime through linking domestic ETS. After comparing emerging emissions trading schemes from an institutional perspective, it emerges that not only emissions trading is at a very early stage in most countries, in addition the emerging systems are probably going to be designed very differently from the EU ETS. While for some design features such as the coverage design differences do not matter, there are some areas where the plans in many non-EU countries look crucially different from the EU system. The outlook for a linked international ETS is therefore currently still very uncertain. Given this state of affairs, the EU should pro-actively engage with the non-EU countries to try to harmonise their developing national emissions trading schemes with the EU ETS, widely disseminate the lessons it has learned from the EU ETS, strongly make the case for environmental integrity and at the same time make clear that systems that want to link to the EU ETS will need to meet certain quality criteria.

2010年2月27日智利地震地球球型自由振荡研究

利用中国数字地震台网（CDSN）5个台站的波形资料,采用功率谱密度估计方法,提取了智利地震激发的地球球型自由振荡,并与地球初步参考模型（PREM）的理论自由振荡周期进行对比,发现球型振荡振型周期与地球初步参考模型预测的球型自由振荡周期基本吻合。所得结果可以进一步用来研究地震震源机制和地球内部结构,并对大地震的震源破裂分布给出一定的约束。     

Towards networked governance: improving interagency communication and collaboration for disaster risk management and climate change adaptation in Australia

Major disasters, such as bushfires or floods, place significant stress on scarce public resources. Climate change is likely to exacerbate this stress. An integrated approach to disaster risk management (DRM) and climate change adaptation (CCA) could reduce the stress by encouraging the more efficient use of pooled resources and expertise. A comparative analysis of three extreme climate-related events that occurred in Australia between 2009 and 2011 indicated that a strategy to improve interagency communication and collaboration would be a key factor in this type of policy/planning integration. These findings are in accord with the concepts of Joined-up Government and Network Governance. Five key reforms are proposed: developing a shared policy vision; adopting multi-level planning; integrating legislation; networking organisations; and establishing cooperative funding. These reforms are examined with reference to the related research literature in order to identify potential problems associated with their implementation. The findings are relevant for public policy generally but are particularly useful for CCA and DRM.