引水隧洞二衬刚度与施作时机优选及系统构建

二次衬砌结构刚度与施作时机优选是隧洞工程中关键问题之一,对于引水隧洞穿越软弱流变围岩洞段则尤为突出.为研究引水隧洞开挖过程中时空效应耦合作用对二衬优选的影响,基于现场围岩和支护结构实测应力变形数据,采用三维粘弹塑性有限元方法,结合开挖和支护设计实际工况考虑二次衬砌施作距掌子面不同距离和不同二衬刚度(厚度),分析了围岩变...     

不同设计基准期地震动参数取值

提出了不同的设计基准期所对应的地震烈度及地震动参数的计算方法，并通过工程实例，对不同设计基准期的地震动参数进行了设计计算。     

安塞油田长6低渗透油藏重复压裂机理与效果分析

采用理论与实际相结合的思路,建立了重复压裂弹性变形方程以及裂缝扩展判据和裂缝流量公式。采用应变能强度作为判据,可以计算出压裂裂缝的扩展方向。裂缝的转向半径随着压裂液视粘度的上升而增大。根据低渗透油藏的生产特点和人工裂缝的渗流特征建立的油藏与裂缝渗流的数学模型可计算重复压裂后流体的采出(注入)量。进行了裂缝导流能力试验,研究了裂缝参数对重复压裂后的动态影响。重复压裂要取得理想的增产效果,一靠尽可能延长支撑缝长,增大泄油面积;二靠增大导流能力。大型重复压裂就是采用大砂量、大排量进行压裂,增大裂缝长度,采用高强度的支撑剂增大了压裂后油层的导流能力。对安塞油田长6层地质特征进行的重复水力压裂作了效果分析。     

2004年河北省的降水特性

结合防汛水情工作的实际，从水文水资源角度系统、客观又有所侧重地分析了2004年河北省降水的时空分布特性、关键性降水出现时机及落区对我省水库蓄水的影响、大中型水库洼淀汛末蓄水状况，不仅探讨了风调雨顺之年的基本特征，而且有助于探索洪水资源化的实现途径。还为及时了解掌握2004年水资源动态变化的新情况，以便合理安排今冬明春生产、生活及生态用水提供了科学依据。     

语音信号实时传输中的动态变长分帧算法

本文给出了一种动态的变长语音分帧算法,此算法以分析语音信号的时域特性为基础,利用音节之间存在空隙这一特性,基于对语音信号中不同性质的音段的分布特性分析,通过动态的阈值调整来实现动态的变长分帧,算法简单快速。实验证明,这一算法能够针对背景噪声的变化,动态调整语音的分帧长度,从而满足实时传输的需要。     

具有行蓄洪区的复杂水系实时洪水预报研究

建立确定和随机相结合的预报模型对复杂水系的实时洪水预报进行研究.确定性模型采用分布式概念性模型进行流域流量过程预报;基于马斯京根法、水文水位法与扩散波非线性水位法,构建河道流量和水位模拟的综合法对河道以及行蓄洪区的洪水进行预报.随机模型采用基于误差自回归的时变遗忘因子最小二乘递推法对误差进行实时校正.以淮河鲁台子以上流域为例,具有行蓄洪区的干流洪水采用河道流量和水位模拟的综合法与实时校正模型按节点有机结合的方法进行预报.预报模型在2007年的大洪水预报中得到了检验,取得了较高的精度.     

提高特高含水期油藏采收率的方法及应用效果

针对胜索油田二区9-10单元的层间非均质和平面非均质性，运用水动力学方法，采用周期注水及增压注水改善单元的水驱油效果。经过6a的实施，单元的开发形势趋好，单元采收率提高9.62%，增加可采储量341.5kt，对同类型非均质性油藏改善水驱油效果，提高最终采收率具有借鉴意义。     

Assessment of impact of water diversion projects on ecological water uses in arid region

In arid regions, large-scale water diversion from rivers leads to significant changes in river flow regimes, which may have large impacts on ecological water uses of river-dependent ecosystems, such as river, lake, wetland, and riparian ecosystems. To assess the integrated impact of water diversion on ecological water uses, we proposed a hierarchy evaluation model composed of four layers representing the evaluation goal, sub-areas of the influenced region, evaluation criteria, and water diversion schemes, respectively. The evaluation criteria for different types of ecological water uses were proposed, and the analytical hierarchy process was used for the integrated assessment. For a river ecosystem, the percentage of mean annual flow was used to define the grade of environmental flow. For a lake ecosystem, water recharge to the lake to compensate the lake water losses was used to assess the ecological water use of a lake. The flooding level of the wetland and the groundwater level in the riparian plain were used to assess the wetland and riparian ecological water uses, respectively. The proposed model was applied to a basin in northern Xinjiang in northwest China, where both water diversion and inter-basin water transfer projects were planned to be carried out. Based on assessment results for the whole study area and two sub-areas, an appropriate scheme was recommended from four planning schemes. With the recommended scheme, ecological water uses of the influenced ecosystems can be maintained at an acceptable level. Meanwhile, economical water requirements can be met to a great extent.     

武汉市长丰低闸施工期安全监测资料分析

对武汉市长江烂泥湖堤长丰低闸重建施工期间的安全监测资料进行了分析。重点分析了闸过水箱涵的结构缝开合、不均匀沉降等变形监测量变化特征及发展趋势 ,并由此对长丰低闸在施工期的安全状态进行了评判