Flood frequency and routing processes at a confluence of the middle Yellow River in China

Floods cause environmental hazards and influence on socio‐economic activities. In this study, we evaluated the historic flood frequency at a confluence in the middle Yellow River, China. A non‐parametric, multivariate, empirical, orthogonal function matrix model, which consists of time correlation coefficients of flood discharge at different gauge stations and flood events was used for the analysis of flood frequency. The model addresses the characteristics of confluent floods such as frequency and the probability in multiple tributary rivers. Flood frequency analysis is often coupled with studies of hydrological routing processes that reduce the flood capacity of the rivers. Flood routing to the confluence were simulated using kinematic wave theory. Results of this flood frequency analysis showed that flooding frequency has intensified in the past 500 years, especially during the 19th century. Flooding in streams above the confluence was more frequent than in streams below the confluence. Over the last 2000 years, concurrent flooding in multiple tributary rivers accounted for 67.5% of the total flooding in the middle Yellow River. Simulation of flood routing processes shows that the decreased flooding capacity and elevated river bed of the shrunken main channel leads to an increased flood wave propagation time (24–52.3 h) in the study area after 1995. The model indicates that human activities, such as constructions of the Sanmenxia Dam, have changed flood routing boundary conditions and have contributed to the increased flood frequency at the confluence. Copyright © 2007 John Wiley & Sons, Ltd.     

10000m^3天然气球罐用WEL—TEN610CF钢焊接冷裂纹敏感性

WEL-TEN610CF钢是日本新日铁公司生产的低裂纹敏感性高强钢,结合我国首台国产化10 000 m3天然气球罐用37 mm厚WEL-TEN610CF钢焊接性试验研究,对该钢焊接冷裂纹敏感性进行了综合评定,为其焊接工艺的制订提供了可靠的依据。     

钻井企业技术创新评价模型研究

随着中国钻井企业改革的深化和市场经济的不断发展完善，在中国钻井企业中将会出现技术创新的热潮。以当前钻井企业所面临的问题与挑战为背景，根据近年来国内外技术创新与评价理论的最新研究成果，结合当前钻井企业技术创新的实际，构建了钻井企业技术创新评价指标体系，运用层次分析法和模糊综合评价法构建了钻井企业的技术创新评价模型，并进行了实例分析。     

The use of natural essential oils as antimicrobial solutions in paper packaging. Part II

We have assessed the antimicrobial, vapor-phase activity of the following natural essential oils (EOs) when used in paraffin-based “active coatings” for paper packaging materials intended to come into contact with foods: clove (Sygzium aromaticum), cinnamon (Cinnamomum zeylanicum), and oregano (Origanum vulgare) EOs, and cinnamaldehyde-enriched cinnamon EO. To our knowledge, this is the first time that such an approach has been presented for consideration by the scientific community.     

油田单井平均日产油量经济极限确定方法

从f(n,t)曲线的研究出发,得到了求解油田单井平均日产油量经济极限值的数学方程式,介绍了用曲线交汇法求解的过程,分析了油田月递减余率和原油销售价是影响油田单井平均日产油量经济极限的主要因素。该方法在油田开发调整方案的编制和油田开发规划部署工作中将起到一定的作用。     

Efficient Management of Persistent Knowledge

Although computer speed has steadily increased and memory is getting cheaper, the need for storage managers to deal efficiently with applications that cannot be held into main memory is vital. Dealing with large quantities of clauses implies the use of persistent knowledge and thus, indexing methods are essential to access efficiently the subset of clauses relevant to answering a query. We introduce PerKMan, a storage manager that uses G-trees, and aims at efficient manipulation of large amounts of persistent knowledge. PerKMan may be connected to Prolog systems that offer an external C language interface. As well as the fact that the storage manager allows different arguments of a predicate to share a common index dimension in a novel manner, it indexes rules and facts in the same manner. PerKMan handles compound terms efficiently and its data structures adapt their shape to large dynamic volumes of clauses, no matter what the distribution. The storage manager achieves fast clause retrieval and reasonable use of disk space.     

提高储层预测精度技术思路与对策

采用地质、地震、测井人员协同一体化作业，对地下地质目标进行综合预测与评价，可提高储层预测精度，降低预测结果的多解性。主要方法是针对不同的区块，采用不同的方法和对策，首先从单井储层划分对比入手，建立储层沉积模式，同时对地震数据目的层段进行精细解释，建立地层构造模式，用沉积、构造等地质规律来指导和约束反演；利用测井资料对地震资料进行精细标定，建立各井的单井波阻抗模型，建立井数据和地震数据沟通的桥梁；在严格的测井约束、地质模型约束、层位控制下进行储层反演；充分利用地质、地震反演结果、地震参数提取及分析结果、测井、测试和分析化验等资料对储层预测结果进行综合分析与评价。该方法应用于长庆、大庆、准噶尔等实际区块，取得了较好的效果。     

表达式句法分析及求值算法在优化设计中的应用

针对优化设计技术在机械工程领域的使用特点提出了一种应用表达式分析与求值原理以避免对每个优化模型或实例均需编程求解的解决方法,论述了该方法的要求、原理、实现过程及应用程序框架。     

麦胚高蛋白乳粉的研制及营养评价

研究了用麦胚浆液与牛乳混合生产高蛋白奶粉的方法。产品的主要特点是具有较高含量的赖氨酸，谷胱甘肽，磷脂，胆碱，不饱和脂肪酸等，这些成分对人体具非了非常的好健脑，抗衰老作用。     

高分辨率电阻率测井仪在薄层评价中的应用

传统的测井仪器无法克服纵向分辨率和径向探测深度这一矛盾，高分辨率电阻率测井仪（HDRT）测量精度好、探测深度大且垂向分辨率高，能够准确识别薄互层、评价薄油气层，准确记录油层厚度，可为精细描述油气田地下地质状态提供更多依据。