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The barrier river reach identification and classification in the Middle Yangtze River

Frontiers of Earth Science 2019年第3期13卷 596-613页

作者： Jinwu TANG Chunyan HU Xingying YOU Yunping YANG Xiaofeng ZHANG Jinyun DENG Meng CHEN Changjiang Institute of Survey Planning Design and Research Wuhan 430010China Hubei Institute of Survey & Design for Water Resources & Water Power Engineering Wuhan 430064China State Key Laboratory of Water Resource and Hydropower Engineering Science Wuhan UniversityWuhan 430072China Key Laboratory of Engineering Sediment Tianjin Research Institute for Water Transport EngineeringMinistry of TransportTianjin 300456China

adjustments of upstream river regimes are one of the main factors affecting downstream fluvial processes. However, not all adjustments of river regimes will propagate downstream. There are some distinctive river reaches where upstream and downstream adjustments have no relevance. However, the irrelevance is neither caused by different river types nor by the different conditions of water and sediment;but rather, the channel boundaries and riverbed morphologies block the propagation effect. These are referred to here as the barrier river reach phenomena. The migration of the thalweg line is the essential reason for causing the propagation effect. Numerous influencing factors for thalweg migration exist, including 1) the average flow rate above the critical bankfull discharge, the average flow rate below the critical bankfull discharge, and their ratio, 2) the ratio of the duration of the aforementioned two periods, 3) the thalweg displacement at the entrance of the river reach, 4) the deflecting flow intensity of the node, 5) the ratio of the river width to water depth, 6) the relative width of the floodplain, and 7) the Shields number. In this study, the correlativity between the measured distances and the restricting indicators of thalweg migration in the Middle Yangtze River over the years was established. The barrier degree of 27 singlethread river reaches was subsequently assessed. These reaches included 4 barrier river reaches;5 transitional reaches transforming from barrier to non-barrier;10 transitional reaches transforming from non-barrier to barrier;and 8 non-barrier river reaches. Barrier river reaches were found to be important for maintaining the stability of the river regime and the transverse equilibrium of sediment transport in the downstream reaches. To some extent, the barrier river reaches may protect the natural dynamical properties from being destroyed by artificial river regulation works. Thus, they are of great significance for river management.

关键词： the barrier river reach Yangtze River channel adjustment thalweg migration identification and classification

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Evaluation of the Momentum Closure Schemes in MPAS-Ocean

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Journal of Ocean University of China 2018年第2期17卷 227-243页

作者： ZHAO Shimei LIU Yudi LIU Wei College of Meteorology and Oceanography Nanjing University of Science and Technology

In order to compare and evaluate the performances of the Laplacian viscosity closure, the biharmonic viscosity closure, and the Leith closure momentum schemes in the MPAS-Ocean model, a variety of physical quantities, such as the relative reference potential energy(RPE) change, the RPE time change rate(RPETCR), the grid Reynolds number, the root mean square(RMS) of kinetic energy, and the spectra of kinetic energy and enstrophy, are calculated on the basis of results of a 3D baroclinic periodic channel. Results indicate that: 1) The RPETCR demonstrates a saturation phenomenon in baroclinic eddy tests. The critical grid Reynolds number corresponding to RPETCR saturation differs between the three closures: the largest value is in the biharmonic viscosity closure, followed by that in the Laplacian viscosity closure, and that in the Leith closure is the smallest. 2) All three closures can effectively suppress spurious dianeutral mixing by reducing the grid Reynolds number under sub-saturation conditions of the RPETCR, but they can also damage certain physical processes. Generally, the damage to the rotation process is greater than that to the advection process. 3) The dissipation in the biharmonic viscosity closure is strongly dependent on scales. Most dissipation concentrates on small scales, and the energy of small-scale eddies is often transferred to large-scale kinetic energy. The viscous dissipation in the Laplacian viscosity closure is the strongest on various scales, followed by that in the Leith closure. Note that part of the small-scale kinetic energy is also transferred to large-scale kinetic energy in the Leith closure. 4) The characteristic length scale L and the dimensionless parameter Г in the Leith closure are inherently coupled. The RPETCR is inversely proportional to the product of Г and L. When the product of Г and L is constant, both the simulated RPETCR and the inhibition of spurious dianeutral mixing are the same in all tests using the Leith closure. The dissipative scale in the Leith closure dep

关键词： 3D baroclinic eddy momentum closure grid Reynolds number the reference potential energy(RPE) baroclinic adjustment kinetic energy enstrophy

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A Perspective of Infrastructure Investment on Stabilizing Growth in China

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China Forex 2022年第2期 35-40页

作者： ZHU Jianfang CITIC Securities

Economic downward pressure since the start of 2022 has seen a notable increase due to disruptions from COVID-19,which causes new difficulties and challenges to achieve the expected growth target set by the government this year.We expect that the macroeconomic counter-cyclical adjustment will be significantly stronger,and infrastructure is one of the most important counter-cyclical adjustment tools.

关键词： adjustment downward challenges

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National 2000' GPS control network of China

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Progress in Natural Science:Materials International 2007年第8期17卷 983-987页

作者： Yang Yuanxi~(1**) Tang Yingzhe~1 Chen Chuanlu~2 Wang Min~3 Zhang Peng~4 Wang Xiaorui~2 Song Lijie~5 Zhang Zusheng~6 (1.Xi'an Research Institute of Surveying and Mapping,Xi'an 710054,China 2.Geodetic Data Processing Center,Xi'an 710054,China 3.Center of Earthquake Analysis and Prediction,China Seismological Bureau,Beijing 100036,China 4.National Geomatics Center of China,Beijing 100044,China 5.Institute of Surveying and Mapping,Zhengzhou University of Information Engineering,Zhengzhou 450052,China 6.First Crustal Deformation Monitoring Center,China Seismological Bureau,Tianjin 300180,China) Xi'an Research Institute of Surveying and Mapping Xi'an 710054 China Geodetic Data Processing Center Xi'an 710054 China Center of Earthquake Analysis and Prediction China Seismological Bureau Beijing 100036 China National Geomatics Center of China Beijing 100044 China Institute of Surveying and Mapping Zhengzhou University of Information Engineering Zhengzhou 450052 China First Crustal Deformation Monitoring Center China Seismological Bureau Tianjin 300180 China

An accurately unified national GPS network with more than 2500 stations,named"National 2000' GPS Control Net- work",signed the epoch 2000.0,has been established by integrating the existing six nationwide GPS networks of China set up by differ- ent departments with different objectives.This paper presents the characteristics of the existing GPS networks,summarizes the strategies in the integrated adjustment of the GPS network,including functional model,stochastic model as well as the adjustment principle modifi- cation.By modifying the adjustment strategies according to the characteristics of the existing GPS networks and under the support of the IGS stations,the accuracy of the integrated national GPS network is greatly improved.The datum differences among the sub networks disappear,the systematic error influences are weakened,and the effects of the outliers on the estimated coordinates and their variances are controlled.It is shown that the average standard deviation for the horizontal component is smaller than 1.0 cm,the vertical component is smaller than 2.0 cm,and the three-dimensional (3-D) position of geocenter coordinates is smaller than 3.0 cm.The exterior checking ac- curacy for the 3-D position is averagely better than 1.0 cm.

关键词： GPS control network adjustment systematic errors robust estimation variance component estimation coordinate system

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One-Step-Installation of Offshore Wind Turbine on Large-Scale Bucket-Top-Bearing Bucket Foundation

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Transactions of Tianjin University 2013年第3期19卷 188-194页

作者：丁红岩练继建李爱东张浦阳 State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Key Laboratory of Coast Civil Structure Safety (Tianjin University) Ministry of Education School of Civil Engineering Tianjin University Daoda Marine Heavy Industry Co. Ltd

In 2010,the first offshore wind turbine with integrated installation was established in Qidong sea area of Jiangsu Province,China,which led to the implementation phase of one-step-installation technique based on the design and construction of large-scale bucket-top-bearing (LSBTB) bucket foundation.The critical technique of LSBTB bucket foundation included self-floating towing,penetration with adjustment of horizontal levelness,removability and one-step-installation.The process of one-step-installation included the prefabrication of LSBTB bucket foundation in onshore construction base,installation and debugging of wind power,overall water transportation of foundation and wind power system,and installation of foundation and offshore wind turbine on the appointed sea area.The cost of one-step-installation technique was about 5 000 Yuan/kW,which was 30%-50% lower than that of the existing technique.The prefabrication of LSBTB bucket foundation took about two months.During the one-step-installation process,the installation and debugging of wind power and overall water transportation need about one to two days in sea area within 35 m depth.After the proposed technique is industrialized,the cost will be further reduced,and the installation capacity is expected to be up to 500 wind turbines per year.

关键词： one-step-installation technique large-scale bucket-top-bearing bucket foundation self-floating towing penetration technique with adjustment of horizontal levelness removability technique construction and installation cost

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adjustment OF RESERVOIR MANAGEMENT

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China Oil & Gas 1998年第1期5卷 22-23页

作者： Peng Jiancheng Zhu Shuiqiao(No.2 Production Plant of Xinjiang Petroleum Administration)

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Evaluation of proline, chlorophyll, soluble sugar content and uptake of nutrients in the German chamomile (Matricaria chamomilla L.) under drought stress and organic fertilizer treatments

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Asian Pacific Journal of Tropical Biomedicine 2016年第10期6卷 886-891页

作者： Amin Salehi Hamidreza Tasdighi Majid Gholamhoseini Agronomy and Plant Breeding Department Yasouj University Oil Seed Crops Department Seed and Plant Improvement Institute Agricultural Research Education and Extension Organization (AREEO)

Objective: To investigate the effect of drought stress and organic fertilizer on German chamomile(Matricaria chamomilla) nutrient uptake, leaf chlorophyll content and osmotic adjustment under field conditions.Methods: This experiment was carried out through a randomized complete block design with a split factorial arrangement of treatments in three replications. The main plots were subjected to the following irrigation treatments: irrigation after 60, 90, 120, 150 and180 mm evaporation from Class A pan. The sub-plots were treated with three vermicompost doses(0, 5 and 10 t/ha).Results: Although drought stress reduced the nutrient percentages in the shoots, application of vermicompost enhanced the nutrient percentages, particularly when the plants were subjected to moderate to severe drought stress conditions. Moreover, the results of this study showed that the interaction between irrigation treatments and vermicompost rates on leaf chlorophyll content was significant. Comparison between the combined treatments indicated that under normal irrigation and moderate drought stress conditions chamomile plants received 5 and 10 t/ha vermicompost showed significantly higher leaf chlorophyll content comparing to the control treatment.Conclusions: Totally, organic fertilization by vermicompost could partly alleviate the effect of drought stress on chamomile by increasing N, P and K uptake and leaf soluble sugar, especially in stressed treatments.

关键词： German chamomile(Matricaria chamomilla) Drought stress Osmotic adjustment Organic fertilizer Vermicompost

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SOECO'S COMPUTER PROGRAMS AND SYSTEMS FOR OFFSHORE ENGINEERING

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China Ocean Engineering 1987年第1期1卷 41-50页

作者：练淦胡恺 Shanghai Offshore Engineering Corporation Shanghai Shanghai Offshore Engineering Corporation Shanghai

This paper introduces the offshore engineering computer programmes worked out independently by SOECO (Shanghai Offshore Engineering Corporation). These computer programmes can be used for static and dynamic analysis of jacket platform. They can also be adopted for other offshore structural calculations, e.g. jack-up and semi-submersible. This enables SOECO to offer a better service for offshore development both at home and abroad.

关键词： offshore launching independently programme completed facilities worked adjustment calculating Bohai

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Real-Time Update of Sequence Placement Logic for High Arch Dams Based on Evidence Weight Discount

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Transactions of Tianjin University 2017年第3期23卷 267-276页

作者： Tao Guan Denghua Zhong Bingyu Ren State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China

Sequence placement logic plays a significant role in construction simulation of high arch dams and directly affects the simulation process and results.To establish a sequence logic for dam block placement,the construction scheme,real-time construction process,and random factors of the site all need to be considered in detail.There are few studies available currently that take all these factors into consideration.To address this problem,a real-time update of sequence placement logic for high arch dams based on evidence weight discount is proposed in this study.First,the subjective weight of the dam block sequence priority criteria is built using a consistent matrix method based on the construction scheme.Second,using evidence theory,dynamic objective weight of the priority criteria and basic probability assignment is built.Finally,using a weight self-adaptive adjustment method and comprehensive evidence discounting,the placing probabilities of different dam blocks are obtained.A case study indicates that this method can realize realtime update of sequence placement logic.

关键词： Sequence placement logic Evidence theory Weight self-adaptive adjustment method Evidence weight discount Real-time update

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The Relationship between Landless Farmers and Land adjustment,Land Transfer,Land Inheritance

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Asian Agricultural Research 2013年第11期5卷 55-62页

作者： Chunrong SHANG Lan YE College of Economics and Management South China Agricultural University

Based on the household survey of nine villages in Guangdong Province and Hunan Province,we research the relationship between landless farmers and land adjustment,land transfer in the context of rural land contract rights on a long term basis.We demonstrate that the existence of landless farmers does not pose a serious problem for the current rural community.We also explain the reason why the land is no longer readjusted:the expected return of land adjustment is low and the organizational costs are high.

关键词： Landless farmers Land adjustment Land transfer Lan

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