Spatial and temporal variability in the pelagic ecosystem of the East Sea (Sea of Japan): A review

The East Sea (Sea of Japan) is a unique marginal sea because it exhibits features of oceanic dynamics of much larger ocean basins. This semi-enclosed basin may be considered as a model or microcosm for understanding of how biological processes and distributions in pelagic ecosystem are interacting with physical processes in highly dynamic ocean regions. This overview summarizes the recent progresses concerning spatial and temporal variability of pelagic ecosystem components form an interdisciplinary point of view. Spatial characteristics of physical environments and biogeography in the region are distinguished mainly by the subpolar front. It was also found that long-term changes in biomass and community structure as well as those in the physical and biological environments are associated with climate variability in the region. We conclude by identifying main needs for the information and researches, particularly regular and long-term sampling, and permanent monitoring if possible.     

长江口横沙东滩滩涂整治利用和展望

分析长江口、横沙东滩历史和近期演变以及利用情况。近期长江口河势总体稳定,在采取人工促淤等措施下,滩涂资源动态平衡。分析横沙东滩滩涂整治利用工程建设前后的滩涂变化,工程周边滩涂淤涨,有助于改善局部区域的自然环境。近期横沙浅滩-5 m滩涂资源有减少趋势,建议结合疏浚土利用以及保持滩涂湿地动态平衡的需求及早整治,有控制性地、分期适当圈围。     

东湖绿道工程设计特点综述

东湖绿道是目前国内最长的5A级城市核心区环湖绿道,它的建成产生了良好的社会效益,被联合国人居署评为"改善中国城市公共空间示范项目",成为武汉打造宜居城市的闪亮名片。结合东湖绿道设计过程中遇到的重点和难点,详述问题的解决过程,总结绿道工程的设计特点和设计理念,为城市绿道设计提供一些方法和经验。     

重庆铁路枢纽东环线CTCS-2信号列控系统贯通方案研究

本文基于重庆铁路枢纽的总体规划,研究了枢纽内与东环线相关的既有、在建及拟建铁路的技术标准,结合高速铁路运输需求,对重庆枢纽东环线列控系统配置进行了分析,提出了能充分利用东环线改善枢纽内运输组织方式和提高信号系统安全的可行方案,可为进一步规划实施重庆枢纽信号系统建设提供有益参考.     

瓯江口中沙采沙对温州港航道的影响研究

采用水动力泥沙环境分析、中沙水域冲淤演变分析、潮流数学模型计算、航道泥沙淤积计算等手段对中沙有限量采沙对温州进出港主航道的影响进行了分析和论证。结果表明,在中沙浅滩进行有限量的采沙基本不会对温州港进出港主航道造成负面影响。     

长江中游牯牛沙水道河床演变规律及整治措施研究

通过对长江中游牯牛沙水道碍航特征、来水来沙特性以及河床演变特征的分析,提出了水道航道总体整治原则和治理思路,并在河工模型试验的基础上提出了河段航道整治总体推荐方案,该方案可以达到河段远期规划航道尺度要求。     

荆岳铁路对东洞庭湖自然保护区自然体系生态完整性的影响分析

新建荆州至岳阳铁路在君山区约有46．52km位于东洞庭湖国家级自然保护区实验区范围内。从植被生产力及碳贮量和景观生态体系质量两方面介绍了东洞庭湖自然保护区自然体系的生态环境质量现状,并分析和预测了工程建成后保护区自然体系生物量、碳贮量及生产力的变化、自然体系的稳定状况。认为荆岳铁路的建设对东洞庭湖自然保护区自然体系生态完整性影响较小。     

基于地球椭球体模型的航迹计算

通过对中分纬度概念的深入研究,给出上一套地球椭球体上中分纬度和航这计算的精确算,式,进而给出其解算的工程数模,为高精度船舶自动化导航的发展提供理论模型。     

General Construction Technology Scheme of Tianshan Shengli Tunnel on Urumqi-Yuli Expressway北大核心CSCD

With a total length of about 22 km, Tianshan Shengli Tunnel on Urumqi-Yuli Expressway is currently the longest expressway tunnel under construction in the world. It adopts the construction scheme of "3 tunnels (2 D& B main tunnels and 1 TBM-driven middle pilot tunnel) + 4 shafts", which is characterized by great construction difficulty and high technical standard requirements. The tunnel construction is faced with technical challenges such as TBM passing through large fault fracture zones, long-distance construction ventilation in three tunnels, deep and large shaft construction and logistics organization in two-main tunnel construction assisted by middle pilot tunnel. In the parallel three-tunnel method design of Tianshan Shengli Tunnel, the TBM-driven middle pilot tunnel can not only play the role of advanced pilot tunnel, but also assist the construction of the two main tunnels and speed up the construction progress. For the middle pilot tunnel, the TBM excavation diameter is 8.4 m, and the initial support is designed as 100% force-bearing capacity in construction period, which can meet the requirements for two-way material transportation, ventilation and belt mucking in the pilot tunnel. Vault suspension scheme is adopted for the continuous belt conveyor, which can reduce the impact on the material flow organization in the cross passages. Multifunctional service vehicles (MSVs) independently developed by CCCC Group are used for the transportation of TBM materials and prefabricated inverted arch blocks, which can realize double-headed driving. TBM will pass through two large fault fracture zones F6 and F7. According to the stability of the surrounding rock at the tunnel face, the targeted treatment measures would be adopted. If necessary, the scheme of "steel segment + extruded concrete" shall be used for the initial support. In case of serious machine jamming or rock collapse, the heading expansion excavation method or bypass heading method shall be used. Tianshan Shengli Tunnel adopts phased forced ventilation option, and the ventilation mode is designed in stages with the change of tunnel construction stage. The fans and air pipes used are imported ones, and a ventilation management team is set up to strengthen ventilation management and ensure ventilation quality. Highly mechanized construction is used for the two D& B main tunnels, the application of equipment such as three-arm rock drilling jumbo and wet shotcrete machine is promoted, so as to reduce the number of workers and labor intensity, and improve work efficiency. The deep shafts of Tianshan Shengli Tunnel are constructed by short-section excavation and lining mixed operation method, and the initial support is lined by formwork pouring concrete, so as to realize safe and rapid excavation. According to the research results, the construction technology scheme for Tianshan Shengli Tunnel can meet the needs of tunnel construction. The research results can be directly used to guide the construction of Tianshan Shengli Tunnel, and provide reference for the construction of extra long highway tunnels in high-altitude areas. © 2022, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

广州铁路集装箱中心站道路配套工程——站场中路工程设计方案研究

以广州铁路集装箱中心站近期道路配套工程——站场中路为背景,从道路交叉节点交通量预测、平面设计、道路纵断面设计方案比选及横断面设计等方面综合论述了工程总体设计方案,此方案不仅可有力支撑铁路集装箱中心站的开发建设、满足中心站建成后的货运交通出入及集散需求、完善区域路网结构,而且可避免道路占用集装箱中心站用地,保证广州铁路集装箱中心站建设工期,为同类铁路集装箱中心站道路配套工程设计提供一定的参考价值.