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A Progressive Line Simplification Algorithm 被引量:2
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作者 Christoph Brandenberger Lorenz Hurni 《Geo-Spatial Information Science》 2002年第3期41-45,75,共6页
An application of line simplification considering spatial knowledge is described.A method for identifying potential conflict regions,in order to avoid the self_intersection of generalized lines,is also discussed.Furth... An application of line simplification considering spatial knowledge is described.A method for identifying potential conflict regions,in order to avoid the self_intersection of generalized lines,is also discussed.Furthermore,a new progressive line simplification algorithm is presented.From the view point of spatial cognition,a spatial hierarchical structure is proposed,and its application to construction of spatial knowledge related to a line is explained. 展开更多
关键词 PROGRESSIVE LINE simplification map GENERALIZATION SPATIAL knowledge SPATIAL cognitive SPATIAL hierarchical structure potential CONFLICT region selfintersection of a LINE
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Simplification and Experimental Verification for Temperature and Humidity Field Coupling Model of Conservatory Soil 被引量:1
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作者 曹滨斌 李惟毅 李兆力 《Transactions of Tianjin University》 EI CAS 2011年第1期33-38,共6页
Based on the surface energy balance model which is widely used abroad, a temperature and humidity field coupling model of conservatory soil without crop vegetation in full illumination was established. Considering the... Based on the surface energy balance model which is widely used abroad, a temperature and humidity field coupling model of conservatory soil without crop vegetation in full illumination was established. Considering the relatively closed environment in conservatory, weak solar radiation and little surface evaporation of soil, the daily variation of water content in different soil layers may be neglected, then the temperature and humidity field coupling model was simplified to a one-dimensional thermal diffusion model. The simplified model and the temperature and humidity field coupling model adopted the same computational method of soil physical parameters and discrete format of heat diffusion differential equations, and were applied to the continuous simulation of temperature field in conservatory soil without crop vegetation in full illumination. Through the comparison between simulation results and experimental data, the precision of the simplified model was verified. The typical rule of soil heat flux variation in a 24 h cycle was also obtained. 展开更多
关键词 conservatory SOIL TEMPERATURE humidity coupling model simplification
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Text Simplification Using Transformer and BERT 被引量:1
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作者 Sarah Alissa Mike Wald 《Computers, Materials & Continua》 SCIE EI 2023年第5期3479-3495,共17页
Reading and writing are the main interaction methods with web content.Text simplification tools are helpful for people with cognitive impairments,new language learners,and children as they might find difficulties in u... Reading and writing are the main interaction methods with web content.Text simplification tools are helpful for people with cognitive impairments,new language learners,and children as they might find difficulties in understanding the complex web content.Text simplification is the process of changing complex text intomore readable and understandable text.The recent approaches to text simplification adopted the machine translation concept to learn simplification rules from a parallel corpus of complex and simple sentences.In this paper,we propose two models based on the transformer which is an encoder-decoder structure that achieves state-of-the-art(SOTA)results in machine translation.The training process for our model includes three steps:preprocessing the data using a subword tokenizer,training the model and optimizing it using the Adam optimizer,then using the model to decode the output.The first model uses the transformer only and the second model uses and integrates the Bidirectional Encoder Representations from Transformer(BERT)as encoder to enhance the training time and results.The performance of the proposed model using the transformerwas evaluated using the Bilingual Evaluation Understudy score(BLEU)and recorded(53.78)on the WikiSmall dataset.On the other hand,the experiment on the second model which is integrated with BERT shows that the validation loss decreased very fast compared with the model without the BERT.However,the BLEU score was small(44.54),which could be due to the size of the dataset so the model was overfitting and unable to generalize well.Therefore,in the future,the second model could involve experimenting with a larger dataset such as the WikiLarge.In addition,more analysis has been done on the model’s results and the used dataset using different evaluation metrics to understand their performance. 展开更多
关键词 Text simplification neural machine translation TRANSFORMER
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A Collaborative Simplification Method for Multiple Coastlines Based on the Hierarchical Triangulation Network Partition 被引量:6
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作者 Lihua ZHANG Lulu TANG +1 位作者 Shuaidong JIA Zeyuan DAI 《Journal of Geodesy and Geoinformation Science》 2020年第2期93-104,共12页
For the current automatic coastline generalization method,only one-line element is considered separately,but the relationship between the nearby elements is not effectively considered.A synergistic simplification meth... For the current automatic coastline generalization method,only one-line element is considered separately,but the relationship between the nearby elements is not effectively considered.A synergistic simplification method for multiple coastlines based on the hierarchical triangulation network partition(HTNP)is proposed in this paper.Firstly,the constrained Delaunay triangulation is constructed to partition the regions that can be simplified.Then,a hierarchical binary tree model to structure the morphological characteristics of the above several coastlines and the spatial proximity between different coastlines is constructed.Finally,the small curved and curved invisible parts of the coastline are deleted according to the visual constraints,and the narrow part between the coastline itself or the different coastlines is exaggerated appropriately,and the automatic simplification of the coastline is realized.The experimental results show that:①Relationships between the different coastlines are considered,and the shortcomings of considering the coastline separately are overcome;②Under the condition of the multiple coastlines in complex sea areas,the problem of collaborative simplification is solved,the quality of the coastlines are improved obviously,and the proposed method can be applied into more types of coastlines. 展开更多
关键词 cartographic generalization coastline simplification hierarchy relationship synergistic simplification
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Simplification of English Sentence Pattern Structure in the Teaching of Translation and Grammar
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作者 汤伟 YANG Ya-lan 《海外英语》 2014年第20期278-279,共2页
In the teaching of translation and grammar,it is essential that the English sentence structure is analyzed and transformation of sentence structures both in English and Chinese in class and after class. However,many k... In the teaching of translation and grammar,it is essential that the English sentence structure is analyzed and transformation of sentence structures both in English and Chinese in class and after class. However,many kinds of English sentences structures prevent the students who study English from getting the basic idea and concept of a sentence in translation or grammatical analysis. In this paper,the author submitted the basic mould of simplification of English sentence structure,and the students can learn and master the translating technique through the simplified English sentence structure. Thus it helps to improve students' competence of translation. 展开更多
关键词 ENGLISH SENTENCE STRUCTURE simplification SV SVO S
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Complex Model Simplification Algorithm with Improved Error Evaluation
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作者 JIANGHong-bo LUYan-sheng TANGBo 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第2期380-384,共5页
Given the framework of incremental mesh simplification based on edgecollapse, the paper proposes a mesh simplification algorithm using an improved approach formeasuring simplification error. The algorithm uses edge co... Given the framework of incremental mesh simplification based on edgecollapse, the paper proposes a mesh simplification algorithm using an improved approach formeasuring simplification error. The algorithm uses edge collapse to simplify the trianglemesh andmaintains surface error approximations using c-error for the faces which have changed after edgecollapse and d-crror for the faces which become degenerated after edge collapse. Also, we reportsome results using a variety of computer graphics models, which can show that the algorithm canachieve the desired simplification effect. 展开更多
关键词 mesh simplification c-crror d-error edge collapse
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The Solid-liquid Transformation of Low-grade Solid Potash Deposit in Dalangtan Basin and the Simplification of the Liquid Phase System
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作者 WANG Xiaohan ZHANG Chao +2 位作者 XIE Shaolei JIA Yongzhong YAO Ying 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期436-436,共1页
We studied the solid-liquid transformation of low-grade solid potash deposit in Dalangtan Basin and simplified the liquid phase system.We did experiments to optimize conditions of the solid-liquid transformation.The S... We studied the solid-liquid transformation of low-grade solid potash deposit in Dalangtan Basin and simplified the liquid phase system.We did experiments to optimize conditions of the solid-liquid transformation.The Suitable 展开更多
关键词 low-grade solid potash deposit solid-liquid transformation liquid phase system simplification
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Terrain Simplification Research in Augmented Scene Modeling
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作者 Ming Delie You Kefei Tian Jinwen Liu Jian State Key Laboratory for Image Processing and Intelligent Control, Institute for Pattern Recognition and Artificial Intelligence , Huazhong University of Science and Technology , Wuhan 430074 Wang Guangju 《Journal of China University of Geosciences》 SCIE CSCD 2001年第4期351-355,共5页
Augmented reality is the merging of synthetic sensory information into a user's perception of a real environment. As one of the most important tasks in augmented scene modeling, terrain simplification research has... Augmented reality is the merging of synthetic sensory information into a user's perception of a real environment. As one of the most important tasks in augmented scene modeling, terrain simplification research has gained more and more attention. In this paper, we mainly focus on point selection problem in terrain simplification using triangulated irregular network. Based on the analysis and comparison of traditional importance measures for each input point, we put forward a new importance measure based on local entropy. The results demonstrate that the local entropy criterion has a better performance than any traditional methods. In addition, it can effectively conquer the 'short-sight' problem associated with the traditional methods. 展开更多
关键词 augmented reality scene modeling terrain simplification triangulated irregular network importance measures local entropy.
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Application of equivalent resistance to simplification of Sutong Bridge piers in tidal river section modeling
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作者 Lei TANG WeiZHANG +1 位作者 Ming-xiao XIE Zhen YU 《Water Science and Engineering》 EI CAS 2012年第3期316-328,共13页
This paper describes some details and procedural steps in the equivalent resistance (E-R) method for simplifying the pier group of the Sutong Bridge, which is located on the tidal reach of the lower Yangtze River, i... This paper describes some details and procedural steps in the equivalent resistance (E-R) method for simplifying the pier group of the Sutong Bridge, which is located on the tidal reach of the lower Yangtze River, in Jiangsu Province. Using a two-dimensional tidal current numerical model, three different models were established: the non-bridge pier model, original bridge pier model, and simplified bridge pier model. The difference in hydrodynamic parameters, including water level, velocity, and diversion ratio, as well as time efficiency between these three models is discussed in detail. The results show that simplifying the pier group using the E-R method influences the water level and velocity near the piers, but has no influence on the diversion ratio of each cross-section of the Xuliujing reach located in the lower Yangtze River. Furthermore, the simplified bridge pier model takes half the calculation time that the original bridge pier model needs. Thus, it is concluded that the E-R method can be use to simplify bridge piers in tidal river section modeling reasonably and efficiently. 展开更多
关键词 E-R method tidal river section pier group simplification numerical modeling
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An Adaptive SVP Simplification Based on Area Difference 被引量:5
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作者 Gen ZHENG Jianhu ZHAO Hongmei ZHANG 《Journal of Geodesy and Geoinformation Science》 2019年第4期53-63,共11页
Sound velocity profile(SVP)data is indispensable in the multi-beam data processing.The sampling density is of great importance for SVP to represent the vertical variation of sound velocity accurately and guarantee the... Sound velocity profile(SVP)data is indispensable in the multi-beam data processing.The sampling density is of great importance for SVP to represent the vertical variation of sound velocity accurately and guarantee the accuracy of sound ray tracing(SRT).However,the SVP also affects the SRT efficiency significantly,especially in deep-sea multi-beam sounding data processing.To improve SRT efficiency and ensure SRT accuracy,an adaptive SVP simplification method based on area difference is proposed in this article.Firstly,the relationship between the area difference of the raw SVP and the simplified one and SRT bias is studied,and the relationship model of them is built.Then,by considering the constraint of SRT accuracy,the SVP simplification method and the simplifying SVP procedure SVP are given.Finally,a deep water experiment is conducted to verify the proposed method.Compared to the existing method,the proposed method improves the robustness,feasibility of SVP simplification as well as the accuracy and efficiency of SRT. 展开更多
关键词 sound velocity profile(SVP)simplification area difference equivalent SVP sound ray tracing(SRT)bias maximum offset of sound velocity(MOV)
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Analysis of a simplification strategy in a nonhydrostatic model for surface and internal wave problems
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作者 Jinghua Zhang Wensheng Jiang Xueqing Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第2期29-43,共15页
This paper examines the simplification strategy of retaining only the nonhydrostatic effect of local acceleration in a three-dimensional fully nonhydrostatic model regarding the submesoscale wave phenomenon in the oce... This paper examines the simplification strategy of retaining only the nonhydrostatic effect of local acceleration in a three-dimensional fully nonhydrostatic model regarding the submesoscale wave phenomenon in the ocean.Elaborate scale analysis of the vertical component of the Reynold-averaged Navier-Stokes(RANS)equation was performed,confirming the rationalization of this simplification.Then,the simplification was implemented in a RANS equation-based nonhydrostatic model NHWAVE(nonhydrostatic WAVE)to make a simplified nonhydrostatic model.Numerical examples were taken to test its performance,including surface sinusoidal waves propagating on an idealized East China Sea topography,tidally induced internal lee waves and small-scale solitary waves.The results show that in a considerably wide range of nonlinear strengths,the simplified nonhydrostatic model can obtain similar results as those in the fully nonhydrostatic model,even for smaller-scale solitary waves.Nonlinearity influences the applicability of the simplification.The stronger the nonlinearity is,the worse the simplified model describes the nonhydrostatic phenomenon.In general,the simplified nonhydrostatic model can simulate surface waves better than internal waves.Improvement of computational efficiency in the simplified nonhydrostatic model is reasonable,reducing the central processing unit time duration in the fully nonhydrostatic model by 16.4%–20.6%.The specially designed algorithm based on the simplified nonhydrostatic equation can remarkably reduce the computational time. 展开更多
关键词 simplification of nonhydrostatic model submesoscale wave internal lee wave
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THE METHOD OF GRAPHIC SIMPLIFICATION OF AREA FEATURE BOUNDARY WITH RIGHT ANGLES
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作者 GUO Qingsheng MAO Jianhua 《Geo-Spatial Information Science》 2000年第2期74-78,共5页
Some rules of simplification of area feature boundary and the method of acquiring spatial knowledge, such as maintaining area and shape of area feature, are discussed. This paper focuses on the progressive method of g... Some rules of simplification of area feature boundary and the method of acquiring spatial knowledge, such as maintaining area and shape of area feature, are discussed. This paper focuses on the progressive method of graphic simplification of area feature boundary with right angles based on its characteristics. 展开更多
关键词 automated map generalization area feature spatial knowledge progressive graphic simplification
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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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Numerical Simulation of the Settling Flux of Biodeposition in a Bay with Cage Culture Through Similarity Theory and a Simplified Pollution Source
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作者 LIU Yao CHEN Yifan GE Changzi 《Journal of Ocean University of China》 CAS CSCD 2024年第1期247-254,共8页
The settling flux of biodeposition affects the environmental quality of cage culture areas and determines their environmental carrying capacity.Simple and effective simulation of the settling flux of biodeposition is ... The settling flux of biodeposition affects the environmental quality of cage culture areas and determines their environmental carrying capacity.Simple and effective simulation of the settling flux of biodeposition is extremely important for determining the spatial distribution of biodeposition.Theoretically,biodeposition in cage culture areas without specific emission rules can be simplified as point source pollution.Fluent is a fluid simulation software that can simulate the dispersion of particulate matter simply and efficiently.Based on the simplification of pollution sources and bays,the settling flux of biodeposition can be easily and effectively simulated by Fluent fluid software.In the present work,the feasibility of this method was evaluated by simulation of the settling flux of biodeposition in Maniao Bay,Hainan Province,China,and 20 sampling sites were selected for determining the settling fluxes.At sampling sites P1,P2,P3,P4,P5,Z1,Z2,Z3,Z4,A1,A2,A3,A4,B1,B2,C1,C2,C3 and C4,the measured settling fluxes of biodeposition were 26.02,15.78,10.77,58.16,6.57,72.17,12.37,12.11,106.64,150.96,22.59,11.41,18.03,7.90,19.23,7.06,11.84,5.19 and 2.57 g d^(−1)m^(−2),respectively.The simulated settling fluxes of biodeposition at the corresponding sites were 16.03,23.98,8.87,46.90,4.52,104.77,16.03,8.35,180.83,213.06,39.10,17.47,20.98,9.78,23.25,7.84,15.90,6.06 and 1.65 g d^(−1)m^(−2),respectively.There was a positive correlation between the simulated settling fluxes and measured ones(R=0.94,P=2.22×10^(−9)<0.05),which implies that the spatial differentiation of biodeposition flux was well simulated.Moreover,the posterior difference ratio of the simulation was 0.38,and the small error probability was 0.94,which means that the simulated results reached an acceptable level from the perspective of relative error.Thus,if nonpoint source pollution is simplified to point source pollution and open waters are simplified based on similarity theory,the setting flux of biodeposition in the open waters can be simply and effectively simulated by the fluid simulation software Fluent. 展开更多
关键词 fluent fluid simulation software pollution source simplification posterior difference ratio similarity theory Spear-man correlation
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Light Simplified Millet Production Technique Adopting Film Mulching and Hole Sowing
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作者 李顺国 刘猛 +6 位作者 宋世佳 程汝宏 赵宇 任晓利 刘斐 南春梅 夏雪岩 《Agricultural Science & Technology》 CAS 2016年第4期887-889,905,共4页
In order to solve the problem that dry-land foxtail millet production completely relies on rainwater with low instable yield and tedious cultivation, Millet Research Institute of Hebei Academy of Agriculture and Fores... In order to solve the problem that dry-land foxtail millet production completely relies on rainwater with low instable yield and tedious cultivation, Millet Research Institute of Hebei Academy of Agriculture and Forestry Sciences integrated a light simplified production technique integrating film mulching, hole sowing and fertilization with mechanized production, forming the light simplified foxtail millet production technique adopting film mulching and hole sowing. This study introduced the light simplified foxtail millet production technique adopting film mulching and hole sowing, including main links such as preparation before sowing, sowing, attached agricultural machines, field management, harvest and residual film recovery. 展开更多
关键词 Foxtail millet Integrated film mulching Hole sowing and fertilization simplification
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Light Simplified Foxtail Millet Cultivation Technique Adopting Furrow Sowing beside Plastic Film Covering Micro-ridges
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作者 夏雪岩 程汝宏 +6 位作者 宋世佳 刘猛 赵宇 任晓利 刘斐 南春梅 李顺国 《Agricultural Science & Technology》 CAS 2016年第4期869-871,876,共4页
In order to solve the problem that dry-land foxtail millet production completely relies on rainwater with the characteristics of low instable yield, manual thinning and weeding, high labor intensity, and labor and tim... In order to solve the problem that dry-land foxtail millet production completely relies on rainwater with the characteristics of low instable yield, manual thinning and weeding, high labor intensity, and labor and time saving, Millet Research Institute of Hebei Academy of Agriculture and Forestry Sciences integrated furrow sowing beside plastic film covering micro-ridges, simplified cultivation and mechanized production, forming the simplified foxtail millet cultivation technique adopting furrow sowing beside plastic film covering micro-ridges. This study introduced the technique points of the simplified foxtail millet cultivation technique adopting furrow sowing beside plastic film covering micro-ridges, including preparation before sowing,sowing, attached agricultural machines, field management, harvest and residual film recovery. 展开更多
关键词 Foxtail millet Integration of furrow sowing beside plastic film covering micro-ridges fertilization and simplified cultivation simplification
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Coach Simplified Structure Modeling and Optimization Study Based on the PBM Method 被引量:2
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作者 ZHANG Miaoli REN Jindong +1 位作者 YIN Ying DU Jian 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第5期1010-1018,共9页
For the coach industry, rapid modeling and efficient optimization methods are desirable for structure modeling and optimization based on simplified structures, especially for use early in the concept phase and with ca... For the coach industry, rapid modeling and efficient optimization methods are desirable for structure modeling and optimization based on simplified structures, especially for use early in the concept phase and with capabilities of accurately expressing the mechanical properties of structure and with flexible section forms. However, the present dimension-based methods cannot easily meet these requirements. To achieve these goals, the property-based modeling (PBM) beam modeling method is studied based on the PBM theory and in conjunction with the characteristics of coach structure of taking beam as the main component. For a beam component of concrete length, its mechanical characteristics are primarily affected by the section properties. Four section parameters are adopted to describe the mechanical properties of a beam, including the section area, the principal moments of inertia about the two principal axles, and the torsion constant of the section. Based on the equivalent stiffness strategy, expressions for the above section parameters are derived, and the PBM beam element is implemented in HyperMesh software. A case is realized using this method, in which the structure of a passenger coach is simplified. The model precision is validated by comparing the basic performance of the total structure with that of the original structure, including the bending and torsion stiffness and the first-order bending and torsional modal frequencies. Sensitivity analysis is conducted to choose design variables. The optimal Latin hypercube experiment design is adopted to sample the test points, and polynomial response surfaces are used to fit these points. To improve the bending and torsion stiffness and the first-order torsional frequency and taking the allowable maximum stresses of the braking and left turning conditions as constraints, the multi-objective optimization of the structure is conducted using the NSGA-II genetic algorithm on the ISIGHT platform. The result of the Pareto solution set is acquired, and the selection strategy of the final solution is discussed. The case study demonstrates that the mechanical performances of the structure can be well-modeled and simulated by PBM beam. Because of the merits of fewer parameters and convenience of use, this method is suitable to be applied in the concept stage. Another merit is that the optimization results are the requirements for the mechanical performance of the beam section instead of those of the shape and dimensions, bringing flexibility to the succeeding design. 展开更多
关键词 COACH STRUCTURE property-based modeling (PBM) simplification MODELING multi-objective optimization
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A simplified multisupport response spectrum method 被引量:1
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作者 Ye, Jihong Zhang, Zhiqiang Liu, Xianming 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2012年第2期243-256,共14页
A simplified multisupport response spectrum method is presented.The structural response is a sum of two components of a structure with a first natural period less than 2 s.The first component is the pseudostatic respo... A simplified multisupport response spectrum method is presented.The structural response is a sum of two components of a structure with a first natural period less than 2 s.The first component is the pseudostatic response caused by the inconsistent motions of the structural supports,and the second is the structural dynamic response to ground motion accelerations.This method is formally consistent with the classical response spectrum method,and the effects of multisupport excitation are considered for any modal response spectrum or modal superposition.If the seismic inputs at each support are the same,the support displacements caused by the pseudostatic response become rigid body displacements.The response spectrum in the case of multisupport excitations then reduces to that for uniform excitations.In other words,this multisupport response spectrum method is a modification and extension of the existing response spectrum method under uniform excitation.Moreover,most of the coherency coefficients in this formulation are simplified by approximating the ground motion excitation as white noise.The results indicate that this simplification can reduce the calculation time while maintaining accuracy.Furthermore,the internal forces obtained by the multisupport response spectrum method are compared with those produced by the traditional response spectrum method in two case studies of existing long-span structures.Because the effects of inconsistent support displacements are not considered in the traditional response spectrum method,the values of internal forces near the supports are underestimated.These regions are important potential failure points and deserve special attention in the seismic design of reticulated structures. 展开更多
关键词 multisupport excitation uniform excitation response spectrum method coherency coefficients simplification comparative study
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采用混合策略联合优化的模糊C-均值聚类信息熵点云简化算法 被引量:1
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作者 黄鹤 黄佳慧 +2 位作者 刘国权 王会峰 高涛 《西安交通大学学报》 EI CAS CSCD 北大核心 2024年第7期214-226,共13页
针对传统聚类算法处理点云简化问题时精度低、耗时长且易丢失特征信息等问题,提出了一种基于动态精英自适应混合策略的鹈鹕算法(DEAMPOA)与加权熵法联合优化的模糊C-均值聚类(FCM)信息熵点云简化算法。采用动态自适应种群混合策略,同时... 针对传统聚类算法处理点云简化问题时精度低、耗时长且易丢失特征信息等问题,提出了一种基于动态精英自适应混合策略的鹈鹕算法(DEAMPOA)与加权熵法联合优化的模糊C-均值聚类(FCM)信息熵点云简化算法。采用动态自适应种群混合策略,同时融合了精英反向化思路,显著提升了鹈鹕优化算法(POA)的收敛趋势和全局寻优能力,提高了寻找FCM最优聚类中心的成功率;利用DEAMPOA结合加权熵法对FCM进行优化,提高鲁棒性的同时增强了搜索精度,得到较好的聚类结果;在8种UCI标准数据集上与4种算法对比进行聚类性能评估实验,验证了所提方法综合性能优越;将所提方法与信息熵融合,并应用在三维点云KITTI数据集简化中。实验结果表明:与包围框简化法、随机采样简化法和特征选择简化法对比,所提方法全局误差简化前后点集之间平均欧式距离(MED)指标分别降低了2.25%、6.93%、5.74%,点云简化效果最优且运行速度满足要求。 展开更多
关键词 C-均值聚类 鹈鹕优化算法 点云简化 信息熵
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兼具求解速度与隐私性的复杂供热管网等值简化模型 被引量:1
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作者 张磊 王满康 +5 位作者 叶婧 向紫藤 陶千惠 杨子龙 周正坤 邱元城 《电力系统保护与控制》 EI CSCD 北大核心 2024年第10期105-117,共13页
电热能源系统模型维度高将会导致求解难度较大。为此,提出一种兼具求解速度与隐私性的复杂供热管网等值简化模型。首先,基于热网拓扑结构特点,提出可对供热管网进行灵活化简的供热管网拓扑简化方法,并根据简化后的管道结构和参数建立复... 电热能源系统模型维度高将会导致求解难度较大。为此,提出一种兼具求解速度与隐私性的复杂供热管网等值简化模型。首先,基于热网拓扑结构特点,提出可对供热管网进行灵活化简的供热管网拓扑简化方法,并根据简化后的管道结构和参数建立复杂供热管网等值简化模型。其次,充分考虑热电联产(combined heat and power,CHP)机组以热定电模式和热网热惯性对旋转备用容量的影响,建立了系统旋转备用模型。基于此,建立了考虑旋转备用约束的电热能源系统调度模型。最后,采用信息间隙决策理论(information gap decision theory, IGDT)处理系统成本与风电不确定度之间的关系。算例结果分析了供热管网拓扑简化方法在不同简化程度下的简化效果,验证了所提模型适用于电热能源系统优化调度,有效地减少优化模型的求解时间。 展开更多
关键词 电热能源系统 拓扑简化 旋转备用 隐私性 风电不确定性
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