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Construction Project Management and Construction Quality Control Strategy
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作者 Qinrong Zhang 《Journal of Architectural Research and Development》 2024年第4期45-50,共6页
With the gradual acceleration of the urbanization process,the construction industry has been developing rapidly.As the key link to ensure the quality and safety of the project,construction management and construction ... With the gradual acceleration of the urbanization process,the construction industry has been developing rapidly.As the key link to ensure the quality and safety of the project,construction management and construction quality control are of great significance to enhance the competitiveness of construction enterprises and realize sustainable development.In this paper,the effective strategy of construction management and the effective strategy of construction quality control will be discussed in depth,aiming at providing useful management and quality control strategies for construction enterprises. 展开更多
关键词 Construction engineering management Construction quality control strategy Quality control point
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Generalized CAPP and synthetic evaluation strategy for production line of accuracy welding
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作者 孔谅 吴毅雄 《China Welding》 EI CAS 2007年第1期25-31,共7页
This paper presents generalized CAPP (G-CAPP) method which deals with macro process planning for multiobjective in the planning stage of production line of accuracy welding (PLAW) based on the features of accuracy... This paper presents generalized CAPP (G-CAPP) method which deals with macro process planning for multiobjective in the planning stage of production line of accuracy welding (PLAW) based on the features of accuracy welding production ( AWP ). G-CAPP offers foundations for prototype design and general equipment sorting, production capacity predication and production analysis by means of simulation and optimization. A synthetic hierarchy evaluation (SHE) model for G-CAPP established according to the planning objective is utilized to estimate the alternate processing plans by using membership function and analytic hierarchy process (AHP) of operational theory. The assembly welding line of hydraulic torque converter (HTC) is as an example of typical A WP to explicate G-CAPP and synthetic evaluating strategy of PLAW. The feasible and rational process configuration strategies of HTC assembly welding line are pointed oat under different planning objective. 展开更多
关键词 generalized CAPP accuracy welding production line macro planning synthetic evaluation strategy
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Evolution of emergent C-points,L-lines,and C-lines in free space 被引量:1
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作者 闫红卫 何德 吕百达 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第5期227-232,共6页
Polarization singularities,which emerge from the incoherent superposition of two vector electric fields with the same frequency,and their evolution in free space are studied analytically and illustrated by numerical e... Polarization singularities,which emerge from the incoherent superposition of two vector electric fields with the same frequency,and their evolution in free space are studied analytically and illustrated by numerical examples.It is shown that there exist C-points,L-lines,in particular,C-lines in incoherently superimposed two-dimensional wavefields.Usually,the C-lines are unstable and disappear during the free-space propagation.The motion,pair creation-annihilation process of the emergent C-points,as well as the distortion of the L-lines may take place,and the degree of polarization of the emergent C-points varies upon propagation and may be less than 1. 展开更多
关键词 vector singular optics emergent C-points L-lines and C-lines incoherent superposition degree of polarization
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m-degree Center-connecting Line of Finite Points Set and Its Properties 被引量:1
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作者 ZHOU Yong-guo 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第2期247-252,共6页
In this paper, we first give the concept of m-degree center-connecting line in n-dimensional Euclidean space Enand investigate its several properties, then we obtain the length of m-degree center-connecting line formu... In this paper, we first give the concept of m-degree center-connecting line in n-dimensional Euclidean space Enand investigate its several properties, then we obtain the length of m-degree center-connecting line formula in finite points set. As its application,we extend the Leibniz formula and length of medians formula in n-dimensional simplex to polytope. 展开更多
关键词 n-dimensional Euclidean space finite points set m-degree center-connectingline PROPERTIES
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NUMERICAL SIMULATION OF MOLTEN POOL AND CONTROL STRATEGY OF KISS POINT IN A TWIN-ROLL STRIP CASTING PROCESS 被引量:2
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作者 G.M. Cao C.G. Li Z. Y. Liu D. Wu G.D. Wang X.H. Liu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2008年第6期459-468,共10页
Coupled turbulent flow, temperature fields of the twin-roll casting strip process were simulated by three-dimensional finite element method. Based on the heat balance calculation and using inverse methods between the ... Coupled turbulent flow, temperature fields of the twin-roll casting strip process were simulated by three-dimensional finite element method. Based on the heat balance calculation and using inverse methods between the simulations and real experiments, the relational models among casting speed, location, and coefficient of heat transfer between molten metal and rolls in different regions are given. In the simulation, the calculated surface temperatures are in good agreement with the measured values. An on-line model of kiss point is derived by simulations and the geometry of molten pool, corresponding control strategy is also proposed. 展开更多
关键词 Twin-roll strip casting Coupled temperature and flow field Numerical simulation Kiss point Control strategy
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Mathematical Definitions of Point, Line and Area Symbols in Cartography 被引量:3
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作者 WEIWenzhan ZHONGYexun +1 位作者 PENGYueying ZHENGHongbo 《Geo-Spatial Information Science》 2003年第3期62-65,共4页
The line cartographic symbol located on the boundary and the point cartographic symbol located by single point are the main body and stress of the map. The cartographic symbols are divided into point, line and area sy... The line cartographic symbol located on the boundary and the point cartographic symbol located by single point are the main body and stress of the map. The cartographic symbols are divided into point, line and area symbol in cartography and traditional educational books, but up to now there is only qualitative description about the three kinds of symbols, there are not the mathematical definitions of point, line and area symbols. This paper tries to solve the problem. The authors propose the mathematical definition about point, line and area cartographic symbol according to the theory of topology and expound their dependence relation. 展开更多
关键词 point cartograrphic symbol line cartographic symbol area cartographicsymbol FIGURE
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Design of Underwater Robot Lines Based on a Hybrid Automatic Optimization Strategy 被引量:2
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作者 Wenjing Lyu Weilin Luo 《Journal of Marine Science and Application》 2014年第3期274-280,共7页
In this paper, a hybrid automatic optimization strategy is proposed for the design of underwater robot lines. Isight is introduced as an integration platform. The construction of this platform is based on the user pro... In this paper, a hybrid automatic optimization strategy is proposed for the design of underwater robot lines. Isight is introduced as an integration platform. The construction of this platform is based on the user programming and several commercial software including UG6.0, GAMBIT2.4.6 and FLUENT12.0. An intelligent parameter optimization method, the particle swarm optimization, is incorporated into the platform. To verify the strategy proposed, a simulation is conducted on the underwater robot model 5470, which originates from the DTRC SUBOFF project. With the automatic optimization platform, the minimal resistance is taken as the optimization goal;the wet surface area as the constraint condition; the length of the fore-body, maximum body radius and after-body's minimum radius as the design variables. With the CFD calculation, the RANS equations and the standard turbulence model are used for direct numerical simulation. By analyses of the simulation results, it is concluded that the platform is of high efficiency and feasibility. Through the platform, a variety of schemes for the design of the lines are generated and the optimal solution is achieved. The combination of the intelligent optimization algorithm and the numerical simulation ensures a global optimal solution and improves the efficiency of the searching solutions. 展开更多
关键词 hybrid optimization strategy automatic optimization platform underwater robot lines hydrodynamic numerical simulation computational fluid dynamics
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Application of Rollout Strategy to Test Points Selection for Integer-Coded Fault Wise Table 被引量:4
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作者 Cheng-Lin Yang Shu-Lin Tian Bing Long 《Journal of Electronic Science and Technology of China》 2009年第4期308-311,共4页
Test points selection for integer-coded fault wise table is a discrete optimization problem. The global minimum set of test points can only be guaranteed by an exhaustive search which is eompurationally expensive. In ... Test points selection for integer-coded fault wise table is a discrete optimization problem. The global minimum set of test points can only be guaranteed by an exhaustive search which is eompurationally expensive. In this paper, this problem is formulated as a heuristic depth-first graph search problem at first. The graph node expanding method and rules are given. Then, rollout strategies are applied, which can be combined with the heuristic graph search algorithms, in a computationally more efficient manner than the optimal strategies, to obtain solutions superior to those using the greedy heuristic algorithms. The proposed rollout-based test points selection algorithm is illustrated and tested using an analog circuit and a set of simulated integer-coded fault wise tables. Computa- tional results are shown, which suggest that the rollout strategy policies are significantly better than other strategies. 展开更多
关键词 Heuristic graph search integer-coded fault wise table optimization rollout strategy test points selection.
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POSITIVE SOLUTIONS FOR SINGULAR BVPs ON THE POSITIVE HALF-LINE ARISING FROM EPIDEMIOLOGY AND COMBUSTION THEORY 被引量:2
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作者 Smaïl Djebali Ouiza Saïfi 闫宝强 《Acta Mathematica Scientia》 SCIE CSCD 2012年第2期672-694,共23页
In this work, we are concerned with the existence and multiplicity of positive solutions for singular boundary value problems on the half-line. Two problems from epi- demiology and combustion theory set on the positiv... In this work, we are concerned with the existence and multiplicity of positive solutions for singular boundary value problems on the half-line. Two problems from epi- demiology and combustion theory set on the positive half-line are investigated upper and lower solution techniques combined with fixed point index on cones in priate Banach spaces. The results complement recent ones in the literature. We use appropriate Banach spaces. The results complement recent ones in the literature. 展开更多
关键词 Fixed points index positive solution singular problem Cone lower andupper solution HALF-line
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A station-keeping strategy for collinear libration point orbits
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作者 Jing L,~(a)) Qishao Lu,and Qi Wang School of Aeronautics Science and Engineering,Beihang University,Beijing 100191,China 《Theoretical & Applied Mechanics Letters》 CAS 2011年第3期78-80,共3页
Spacecrafts in periodic or quasi-periodic orbits near the collinear libration points are proved to be excellent platforms for scientific investigations of various phenomena.Since such periodic or quasi-periodic orbits... Spacecrafts in periodic or quasi-periodic orbits near the collinear libration points are proved to be excellent platforms for scientific investigations of various phenomena.Since such periodic or quasi-periodic orbits are exponentially unstable,the station-keeping maneuver is needed. A station-keeping strategy which is found by an analytical method is presented to eradicate the dominant unstable component of the libration point trajectories.The inhibit force transforms the unstable component to a stable component.In this method,it is not necessary to determine a nominal orbit as a reference path. 展开更多
关键词 analytical method libration points station-keeping strategy periodic or quasi-periodic orbits
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Discrete Arzelà-Ascoli Theorem on the Half Line and Its Application
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作者 LU YAN-QING MA RU-YUN 《Communications in Mathematical Research》 CSCD 2018年第3期221-229,共9页
The compactness criterion in l◇={x(·)∈l^∞(0,∞))|lim t→∞ x(t)=x(∞)} is given and as an application,we study the existence of positive solutions of second order boundary value problems of differenc... The compactness criterion in l◇={x(·)∈l^∞(0,∞))|lim t→∞ x(t)=x(∞)} is given and as an application,we study the existence of positive solutions of second order boundary value problems of difference equation on the half line by the fixedpoint theorem in cones. 展开更多
关键词 discrete Arzela-Ascoli theorem half line positive solution difference equation fixed point
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Loop Closure Detection of Visual SLAM Based on Point and Line Features
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作者 Chang’an Liu Ruiying Cheng Lijuan Zhao 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2020年第2期58-64,共7页
For traditional loop closure detection algorithm,only using the vectorization of point features to build visual dictionary is likely to cause perceptual ambiguity.In addition,when scene lacks texture information,the n... For traditional loop closure detection algorithm,only using the vectorization of point features to build visual dictionary is likely to cause perceptual ambiguity.In addition,when scene lacks texture information,the number of point features extracted from it will be small and cannot describe the image effectively.Therefore,this paper proposes a loop closure detection algorithm which combines point and line features.To better recognize scenes with hybrid features,the building process of traditional dictionary tree is improved in the paper.The features with different flag bits were clustered separately to construct a mixed dictionary tree and word vectors that can represent the hybrid features,which can better describe structure and texture information of scene.To ensure that the similarity score between images is more reasonable,different similarity coefficients were set in different scenes,and the candidate frame with the highest similarity score was selected as the candidate closed loop.Experiments show that the point line comprehensive feature was superior to the single feature in the structured scene and the strong texture scene,the recall rate of the proposed algorithm was higher than the state of the art methods when the accuracy is 100%,and the algorithm can be applied to more diverse environments. 展开更多
关键词 LOOP CLOSURE DETECTION SLAM visual DICTIONARY POINT and line features
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A geological and functional “three-step strategy” for renminbi's internationalization
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作者 王元龙 《China Economist》 2009年第6期78-85,共8页
Internationalization of the renminbi is the only option for China to fully integrate into the global economic and financial systems. It is not only necessary but imperative as well. With the discussion of advancing re... Internationalization of the renminbi is the only option for China to fully integrate into the global economic and financial systems. It is not only necessary but imperative as well. With the discussion of advancing renminbi internationalization, benef its and costs must be addressed. We need to closely monitor possible risks and bring out the benefits while averting disadvantages. The overall strategy is to consolidate the groundwork and at the same time actively advance renminbi internationalization and opt for a "three-step" strategy at both strategic and policy levels. To overcome the constraints standing in the way of renminbi internationalization, the basic goals should be: to enhance the readiness of renminbi internationalization, dialectically assess the preconditions, and increase the currency's international circulation as a way to achieve major progress in renminbi internationalization. 展开更多
关键词 RENMINBI INTERNATIONALIZATION strategy BREAKTHROUGH point
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Line positions,intensities,and Einstein A coefficients for 3-0 band of^(12)C^(16)O:A spectroscopy learning method
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作者 Zhi-Xiang Fan Zhi-Zhang Ni +7 位作者 Jie-Jie He Yi-Fan Wang Qun-Chao Fan Jia Fu Yong-Gen Xu Hui-Dong Li Jie Ma Feng Xie 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第12期370-377,共8页
Based on the model-and data-driven strategy,a spectroscopy learning method that can extract the novel and hidden information from the line list databases has been applied to the R branch emission spectra of 3-0 band o... Based on the model-and data-driven strategy,a spectroscopy learning method that can extract the novel and hidden information from the line list databases has been applied to the R branch emission spectra of 3-0 band of the ground electronic state of^(12)C^(16)O.The labeled line lists such as line intensities and Einstein A coefficients quoted in HITRAN2020 are collected to enhance the dataset.The quantified spectroscopy-learned spectroscopic constants is beneficial for improving the extrapolative accuracy beyond the measurements.Explicit comparisons are made for line positions,line intensities,Einstein A coefficients,which demonstrate that the model-and data-driven spectroscopy learning approach is a promising and an easy-to-implement strategy. 展开更多
关键词 carbon monoxide line lists a model-and data-driven strategy spectroscopy learning
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Instantaneous Point, Line, and Plane Motions Using a Clifford Algebra
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作者 Kwun-Lon Ting Yi Zhang 《机械设计与研究》 CSCD 2004年第z1期107-110,共4页
The motions of points, lines, and planes, embedded in a rigid body are expressed in a unified algebraic framework using a Clifford algebra. A Clifford algebra based displacement operator is addressed and its higher de... The motions of points, lines, and planes, embedded in a rigid body are expressed in a unified algebraic framework using a Clifford algebra. A Clifford algebra based displacement operator is addressed and its higher derivatives from which the coordinate-independent characteristic numbers with simple geometric meaning are defined. Because of the coordinate independent feature, no tedious coordinate transformation typically found in the conventional instantaneous invariants methods is needed. 展开更多
关键词 Instantaneous kinematics Motion characteristic CURVATURE theory POINT trajectory line trajectory Plane TRAJECTORY
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On Optimal Non-Overlapping Segmentation and Solutions of Three-Dimensional Linear Programming Problems through the Super Convergent Line Series
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作者 Thomas Ugbe Polycarp Chigbu 《American Journal of Operations Research》 2017年第3期225-238,共14页
The solutions of Linear Programming Problems by the segmentation of the cuboidal response surface through the Super Convergent Line Series methodologies were obtained. The cuboidal response surface was segmented up to... The solutions of Linear Programming Problems by the segmentation of the cuboidal response surface through the Super Convergent Line Series methodologies were obtained. The cuboidal response surface was segmented up to four segments, and explored. It was verified that the number of segments, S, for which optimal solutions are obtained is two (S = 2). Illustrative examples and a real-life problem were also given and solved. 展开更多
关键词 AVERAGE Information Matrix Experimental Space line SEARCH Algorithm Support points OPTIMAL Solution
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The Spatial Characteristics of a Line and Their Application to Line Simplification
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作者 GUOQingsheng ChristophBrandenberger 《Geo-Spatial Information Science》 2002年第1期62-67,共6页
This paper discusses the spatial knowledge related to a line ,and the characteristic points of lines is detected.According to the requirements of line generalization,new algorithms for identifying characteristic line ... This paper discusses the spatial knowledge related to a line ,and the characteristic points of lines is detected.According to the requirements of line generalization,new algorithms for identifying characteristic line points are presented.These characteristic points are used to improve the algorithms of line generalization.An algorithm for identifying bends is shown.In this paper,improved algorithms based on those by Douglas_Peucker,Visvalingam and Whyatt are shown.In this test,the progressive process of line generalization is emphasized. 展开更多
关键词 spatial knowledge characteristic point BEND automated map generalization line simplification progressive map generalization
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Simulation of detection and scattering of sound waves by the lateral line of a fish
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作者 V M Adamyan I Y Popov +1 位作者 I V Blinova V V Zavalniuk 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第2期398-404,共7页
A solvable model of lateral line of a fish based on a wave equation with additional boundary conditions on a set of isolated points is proposed.Within the framework of this model it is shown that the ratio of pressure... A solvable model of lateral line of a fish based on a wave equation with additional boundary conditions on a set of isolated points is proposed.Within the framework of this model it is shown that the ratio of pressures on lateral lines on different fish flanks,as well as the cross section of sound scattering on both the lines,strongly depends on angles of incidence of incoming sound waves.The strong angular dependence of the pressure ratio seems to be sufficient for the fish to determine the directions from which the sound is coming. 展开更多
关键词 acoustic equation point self-adjoint perturbations of Laplace operator SCATTERING lateral line
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Investigation on Effects of Mooring Line Fractures and Connector Failures for A Hybrid Modular Floating Structure System
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作者 LIU Ya-qiong REN Nian-xin OU Jin-ping 《China Ocean Engineering》 SCIE EI CSCD 2022年第6期880-893,共14页
The present work reports a Hybrid Modular Floating Structure(HMFS)system with typical malfunction conditions.The effects of both fractured mooring lines and failed connectors on main hydrodynamic responses(mooring lin... The present work reports a Hybrid Modular Floating Structure(HMFS)system with typical malfunction conditions.The effects of both fractured mooring lines and failed connectors on main hydrodynamic responses(mooring line tensions,module motions,connector loads and wave power production)of the HMFS system under typical sea con-ditions are comparatively investigated.The results indicate that the mooring tension distribution,certain module motions(surge,sway and yaw)and connector loads(Mz)are significantly influenced by mooring line fractures.The adjacent mooring line of the fractured line on the upstream side suffers the largest tension among the remaining mooring lines,and the case with two fractured mooring lines in the same group on the upstream side is the most dangerous among all cases of two-line failures in view of mooring line tensions,module motions and connector loads.There-fore,one emergency strategy with appropriate relaxation of a proper mooring line has been proposed and proved effective to reduce the risk of more progressive mooring line fractures.In addition,connector failures substantially affect certain module motions(heave and pitch),certain connector loads(Fz and My)and wave power production.The present work can be helpful and instructive for studies on malfunction conditions of modular floating structure(MFS)systems. 展开更多
关键词 Hybrid Modular Floating Structure(HMFS)system mooring line fractures connector failures hydrodynamic responses emergency strategy
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THEORY AND METHOD FOR WETLAND BOUNDARY DELINEATION
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作者 YIN Shu-bai LU Xian-guo 《Chinese Geographical Science》 SCIE CSCD 2006年第1期56-62,共7页
Based on the analysis of the subjectivity of wetland boundary criteria and their causes at present, this paper suggested that, under the condition that the mechanism of wetland formation process has not been understoo... Based on the analysis of the subjectivity of wetland boundary criteria and their causes at present, this paper suggested that, under the condition that the mechanism of wetland formation process has not been understood, "black box" method of System Theory can be used to delineate wetland boundaries scientifically. After analyzing the difference of system construction among aquatic habitats, wetlands and uplands, the lower limit of rooted plants was chosen as the lower boundary criterion of wetlands. Because soil diagnostic horizon is the result of the long-term interaction among all environments, and it is less responsive than vegetation to short-term change, soil diagnostic horizon was chosen as the indicator to delineate wetland upper boundary, which lies at the thinning-out point of soil diagnostic horizon. Case study indicated that it was feasible using the lower limit of rooted plants and the thinning-out point of soil diagnostic horizon as criteria to delineate the lower and upper boundaries of wetland. In the study area, the thinning-out line of albic horizon was coincident with the 55.74m contour line, the maximum horizon error was less than 1m, and the maximum vertical error less than 0.04m. The problem on wetland definition always arises on the boundaries. Having delineated wetland boundaries, wetlands can be defined as follows: wetlands are the transitional zones between uplands and deepwater habitats, they are a kind of azonal complex that are inundated or saturated by surface or ground water, with the lower boundary lying at the lower limit of rooted plants, and the upper boundary at the thinning-out line of upland soil diagnostic horizon. 展开更多
关键词 wetland boundary "black box" method soil diagnostic horizon thinning-out point line wetland definition
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