万家寨引黄工程隧洞掘进与衬砌

山西省万家寨引黄工程的实践说明，在一定洞径范围内采用TBM法施工，六角形管片衬砌，能够实现高速度与高质量的统一，为大型跨流域调水工程提供了可借鉴的经验。本文对引黄工程采用TBM法施工不同阶段的质量状况进行了初步总结，重点讨论了止水设置，豆砾石回填灌浆，护盾形式，导向杆与连接销等主要结构问题。     

An adaptive color similarity function suitable for image segmentation and its numerical evaluation

In this article, we present an adaptive color similarity function defined in a modified hue‐saturation‐intensity color space, which can be used directly as a metric to obtain pixel‐wise segmentation of color images among other applications. The color information of every pixel is integrated as a unit by an adaptive similarity function thus avoiding color information scattering. As a direct application we present an efficient interactive, supervised color segmentation method with linear complexity respect to the number of pixels of the input image. The process has three steps: (1) Manual selection of few pixels in a sample of the color to be segmented. (2) Automatic generation of the so called color similarity image (CSI), which is a gray level image with all the gray level tonalities associated with the selected color. (3) Automatic threshold of the CSI to obtain the final segmentation. The proposed technique is direct, simple and computationally inexpensive. The evaluation of the efficiency of the color segmentation method is presented showing good performance in all cases of study. A comparative study is made between the behavior of the proposed method and two comparable segmentation techniques in color images using (1) the Euclidean metric of the a* and b* color channels rejecting L* and (2) a probabilistic approach on a* and b* in the CIE L*a*b* color space. Our testing system can be used either to explore the behavior of a similarity function (or metric) in different color spaces or to explore different metrics (or similarity functions) in the same color space. It was obtained from the results that the color parameters a* and b* are not independent of the luminance parameter L* as one might initially assume in the CIE L*a*b* color space. We show that our solution improves the quality of the proposed color segmentation technique and its quick result is significant with respect to other solutions found in the literature. The method also gives a good performance in low chromaticity, gray level and low contrast images. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 156–172, 2017     

Wood processing variables and adhesive joint performance

In order to obtain a bonded wood product from the tree, wood must be subjected to a series of processes. These include, among others, vital processes like drying of the green wood and machining of the surfaces of the dried wood in preparation for bonding. However, when wood is machined with dull blades, thermal degradation of the wood frequently occurs. The effects of kiln drying and thermal degradation of wood on the performance of the adhesive joints subsequently formed from such wood were investigated. Tapered double cantilever beam (TDCB) test specimens obtained from hard maple and phenol–resorcinol–formaldehyde (PRF) adhesives were used in the investigations. The enhancement of fracture energy due to the reduction in the moisture content of wood, the improved performance of adhesive joints due to rejointing of wood surfaces before bonding, and the reduction of adhesive joint strength resulting from thermal degradation of wood are presented and discussed.     

开发区生态系统健康评估体系的探讨

在国内外学者对生态系统及生态系统健康理论研究的基础上,提出了开发区生态系统的概念及开发区生态系统健康的概念,并结合开发区生态系统的功能和特点,运用系统分析理论建立了开发区生态系统健康指标体系,提出了开发区生态系统健康标准及评价等级,构建了开发区生态系统健康评价模型。通过实例分析,该评价模型能够为开发区的开发、规划提供依据,使开发区在产业发展的同时也能够为人类提供一个优良的生态环境,促使自然-经济-社会系统协调发展。     

APPLICATION OF LBM-SGS MODEL TO FLOWS IN A PUMPING-STATION FOREBAY

A 2-D Lattice Boltzmann Method (LBM) coupled with a Sub-Grid Stress (SGS) model is proposed and validated by flows around a non-submerged spur dike in a channel. And then the LBM-SGS model is further applied to flows in a pumping-station forebay. Shallow water equations are numerically solved by the LBM and the turbulence can be taken into account and modeled efficiently by the Large Eddy Simulation (LES) model. The bounce-back scheme of the non-equilibrium part of the distribution function is used at the inlet boundary, the normal gradient of the distribution function is set as zero at the outlet boundary and the bounce-back scheme is applied to the solid wall to ensure non-slip boundary conditions. Firstly, the model successfully predicts the flow characteristics around a spur dike, such as circulating flow, velocity and water depth distributions. The results are verified by the experimental data and compared to the results obtained by conventional Smagoringsky Model (SM) of LES. Finally, the LBM-SGS model is used to further predict the flow characteristics in a forebay, such as secondary flow and water level. The comparisons show that the model scheme has the capacity to simulate complex flows in shallow water with reasonable accuracy and reliability.     

EXPERIMENTAL INVESTIGATION OF EFFECT OF TIDE ON COASTAL GROUNDWATER TABLE

In this article,a tide simulation system based on a two-way water pump technique is developed.Using this system and numerical simulations,the groundwater table fluctuation characteristics,relative over height of groundwater table,and influencing factors of over height are investigated.The experimental and numerical results indicate that the groundwater table fluctuation is of periodic,and of asymmetric.The amplitude of groundwater table fluctuations decreases with the increase of the onshore distances.There...     

海河流域水资源规划工作思路及初步成果

海河流域水资源短缺,影响着整个流域社会经济的发展。为了更好地研究海河流域水资源的可持续利用,海河水利委员会组织的海河流域水资源规划工作已全面展开。目前,对流域的水资源量、水质状况、供用水现状等进行了调查分析,并取得了初步的成果。     

三峡二期工程施工及关键性技术

本文重点介绍了混凝土生产与温度控制、金属结构及机电设备等施工情况和关键性技术。三峡工期工程需浇筑混凝土1846万m~3,安装金属结构及机电设备埋件19.2万t,施工工期6年。     

小浪底大坝的设计特点及施工新技术

小浪底大坝防渗措施的选择是大坝设计的核心，反滤设计是保证防渗安全和有效的关键。大坝的斜心墙与混凝土防治在墙作为坝基防渗的第一６道防线，上游围堰下游坡设置的上爬式内铺盖与坝前淤积形成的天然铺盖相连，作为坝基防治在的第二道防线，充分体现了利用黄河多泥水特点的设计思想。大坝防渗墙工程施工中大量采用新技术、新方法，设计和施工均代表了当代碾土石坝的发展水平。     

垂直防渗墙新技术在长江重要堤防隐蔽工程中的应用

长江中下游堤防存在着一定的隐患，以致洪水期易发生管涌等险情。垂直防渗墙新技术在除险加固工程中的应用，将使防洪能力大为提高。在长江重要堤防隐蔽工程中应用的成墙技术主要有：薄壁抓斗成槽造墙、射水法成槽造墙、锯槽成墙、等。