油藏高含水阶段CO_2水气交替驱研究及应用

针对油田开发中后期含水率高难控制的问题,提出了CO2水气交替驱提高采收率的方法,采取室内驱替实验和矿场试验对驱油效果进行了评价。室内实验表明:岩心高含水阶段水气交替驱提高采收率效果明显,原油粘度和水气体积比对驱替效率的影响存在最佳区间。矿场试验表明:水气交替注入后单井日产油量提高22倍,含水率下降24.7%,阶段累积增油4721.2t,具有向其他高含水油田推广应用的价值。     

柔性测斜仪在公路边坡自动化监测中应用研究

为了深入理解营运高速公路高边坡深部位移的变形机理,更好地进行防灾减灾工作,使用阵列式位移传感器(SAA)对营运高速公路高边坡进行深部位移动态监测,并同时使用人工测斜仪进行数据对比分析。通过4G网络建立了无线数据传输系统,实现对边坡体全天候监测。试验结果表明:在营运高速公路高边坡深部位移监测中,使用阵列式位移传感系统与无线数据传输系统进行监测,不仅能够实时监测到边坡体深部位移的变形情况,还能判断出滑移面具体位置。相较于人工测斜仪监测,阵列式位移传感系统测量精度和效率更高,在公路高边坡监测中具有广阔的发展前景。     

基于施工全过程的深圳某深基坑工程监测分析

以深圳某深基坑工程为例,基于施工全过程的监测数据,分析不同施工阶段的沉降、水平位移、锚索轴向拉力和基坑周边地下水位的变化规律.监测数据显示基坑周边地面沉降、立柱沉降、支护桩水平变形和基坑周边地面变形均在报警值范围内,表明该基坑支护方案是合理的.此外,坑内土方开挖卸荷会导致坑底产生回弹变形,立柱有微弱隆起变形.临近的地铁风亭结构沉降与水平变形均最明显.部分监测点累积地下水位下降幅度超过报警值和控制值.施工单位需采取合适的措施(如回灌)控制因地下水位大幅下降引起的基坑附加沉降.     

直接基于位移的抗震设计理论及应用

基于位移的抗震设计是指在一定水准的设计地震作用下,以预期的结构位移反应为设计目标,从而实现结构在设计地震作用下的预期性能要求。文章简要阐述直接基于位移的抗震设计理论及方法,介绍用该方法对框架结构进行设计的设计过程,并提出了该方法在今后的研究和应用中需要解决的问题。     

新型油水分离剂在现场的试验评价

孤岛油田进入特高含水开发期，注聚、稠油热采等三次采油工艺和其他增产措施应用后，采出液的原油密度和粘度增大、聚合物含量增加，使原油脱水和污水处理难度越来越大、对在孤岛采油厂四号联合站进行现场测试的最新研制的油水分离剂的油水分离效果．进行了全面系统的分析评价。     

天然气长输管道氮气隔离法投产置换工艺研究

以长庆气田至呼和浩特天然气管道建设工程为背景，探讨了氮气隔离法置换工艺在天然气长输管道投产中的应用。通过对采用单隔离器和无隔离器的两种天然气置换工艺进行分析比较，得出了无隔离器的氮气隔离置换工艺是目前比较理想的天然气置换工艺。     

Two empirical issues in the analysis for the effect of free streaming on music CD and concerts

We address the two measurement issues in the analysis for the effect of free streaming on the consumption of CD and live concerts. One is measurement type for usage of free files and the other is how to measure consumption of ancillary markets, live concerts. Our results indicate that CD purchase is not affected by free streaming use, not supporting the displacement or sampling effect. Meanwhile, results clearly show that streaming use increases the expenditure for music concerts, supporting positive externality of free files. Regarding the measurement issues, we find better goodness-of-fit when we use the continuous time variable rather than the dichotomous dummy for streaming use and find a clearer externality when we use the expenditure rather than frequency for the consumption of concerts.     

基于FLAC3D隧道初期支护方案研究—以青医西院区站隧道为例

利用FLAC3D软件建立两种不同初期支护方式作用下的隧道模型,对隧道的开挖与支护过程进行模拟,分析围岩与支护结构的受力和变形,对比其应力分布和围岩位移情况,选出更为合理的支护方案。研究发现：预应力锚杆能够及时为隧道围岩提供支护作用,不存在支护时效的问题,而普通水泥砂浆锚杆需等地层产生变位后才能发挥作用。     

An equilibrium displacement approach to oligopoly market analysis: an application to trade in the Korean infant formula market

This article uses an equilibrium displacement model (EDM) to assess the impact of a change in trade policy in the Korean infant formula market that is assumed to be oligopolistic. Domestic oligopolists compete in a market for a homogenous good with importing firms who enjoy the same level of market power as the domestic producers. Within an EDM framework, we investigate how the market adjusts to a new equilibrium in response to an external policy shock that improves access to foreign goods. Our empirical work consists of two steps. We first econometrically estimate the market demand elasticity and market power parameter. Then, using these estimates, we simulate our EDM model to assess the distributional effects of tariff cuts and other changes in marginal cost. Simulation results show that, with a lower market price and increased consumption, the change in consumer surplus resulting from tariff reduction is unambiguously positive, but that the change in social welfare can be in either direction, depending on who receives market rents associated with imports. When importing firms are domestic, the domestic welfare change is definitely positive. However, in the case of foreign importing firms, the direction of the welfare change crucially depends on the demand elasticity.