scholarly journals A Comparison of Grid Quality of Optimized Spherical Hexagonal–Pentagonal Geodesic Grids

2005 ◽  
Vol 133 (10) ◽  
pp. 2817-2833 ◽  
Author(s):  
Hiroaki Miura ◽  
Masahide Kimoto
Keyword(s):  
Common Ground ◽  
Optimization Methods ◽  
Optimization Method ◽  
Numerical Schemes ◽  
Optimal Method ◽  
Grid Optimization

Abstract Construction and optimization methods of spherical hexagonal–pentagonal geodesic grids are investigated. The objective is to compare grid structures on common ground. The distinction between two types of hexagonal–pentagonal grids is made. Three conventional grid optimization methods are summarized. In addition, three new optimization methods are proposed. Six desirable conditions for an ideal grid are described, and the grid optimization methods are organized in view of such conditions. Interval uniformity, area uniformity, isotropy, and bisection of cell faces are systematically investigated for optimized grids. There are compensations of preferable grid features in each optimization method, and an optimal method cannot be decided based only on the research of grid features. It is suggested that grid optimization methods should be selected based on research of numerical schemes.

The Research of Dynamic Optimization Method on Automobile Shock Absorption Twist Bar Spring Design

2009 ◽  
Vol 16-19 ◽  
pp. 415-419
Author(s):  
Gui Qiu Song
Keyword(s):  
Dynamic Optimization ◽  
Optimization Design ◽  
Optimization Methods ◽  
Optimization Method ◽  
Random Load ◽  
Optimal Method ◽  
New Approach ◽  
Recent Developments ◽  
Spring System ◽  
Automobile Components

This paper presents recent developments in the study of optimization methods for industrial product design, and provides a method of dynamic optimization design to calculate the optimal loading property of automobile twist bar spring system. This is a different approach to traditional systems that is based on dynamic and random load, applying the basic theory and methods of dynamic design, according to the multi-goal characteristic of automobile twist bar spring. This paper presents a thorough analysis dynamic quadratic fuzzy optimal method of double-goal and the method to determine paper optimal gene. This method is used to automobile twist bar spring design, the result shows that the ability of spring loading is improved; the weight of structure is reduced. The new approach makes the vibration absorbing system more reliable and comfortable. The results presented in this paper are not only applicable to automobile twist bar spring systems but all systems that possess dynamic, random and fuzzy characteristics. This work finds applications in automobile components design and dynamic character analysis.

Metrics for Quality Assessment of a Multiobjective Design Optimization Solution Set

2000 ◽  
Author(s):  
Jin Wu ◽  
Shapour Azarm
Keyword(s):  
Multiobjective Optimization ◽  
Pareto Frontier ◽  
Optimization Methods ◽  
Optimization Method ◽  
Solution Set ◽  
Pareto Solution ◽  
Vibrating Platform ◽  
Pareto Solution Sets ◽  
Multiobjective Design

Abstract In this paper, several new set quality metrics are introduced that can be used to evaluate the ‘goodness’ of an observed Pareto solution set. These metrics, which are formulated in closed-form and geometrically illustrated, include coverage difference, Pareto spread, accuracy of an observed Pareto frontier, number of distinct choices and cluster. The metrics should enable a designer either monitor the quality of an observed Pareto solution set as obtained by a multiobjective optimization method, or compare the quality of observed Pareto solution sets as reported by different multiobjective optimization methods. A vibrating platform example is used to demonstrate the calculation of these metrics for an observed Pareto solution set.

scholarly journals An Overall Uniformity Optimization Method of the Spherical Icosahedral Grid Based on the Optimal Transformation Theory

Atmosphere ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1516
Author(s):  
Fuli Luo ◽  
Xuesheng Zhao ◽  
Wenbin Sun ◽  
Yalu Li ◽  
Yuanzheng Duan
Keyword(s):  
Transportation Cost ◽  
Optimization Methods ◽  
Optimization Method ◽  
Cell Decomposition ◽  
Optimization Approach ◽  
Transformation Theory ◽  
Grid Deformation ◽  
Centroidal Voronoi Tessellations ◽  
Grid Optimization ◽  
Simulation Errors

The improvement of overall uniformity and smoothness of spherical icosahedral grids, the basic framework of atmospheric models, is a key to reducing simulation errors. However, most of the existing grid optimization methods have optimized grid from different aspects and not improved overall uniformity and smoothness of grid at the same time, directly affecting the accuracy and stability of numerical simulation. Although a well-defined grid with more than 12 points cannot be constructed on a sphere, the area uniformity and the interval uniformity of the spherical grid can be traded off to enhance extremely the overall grid uniformity and smoothness. To solve this problem, an overall uniformity and smoothness optimization method of the spherical icosahedral grid is proposed based on the optimal transformation theory. The spherical cell decomposition method has been introduced to iteratively update the grid to minimize the spherical transportation cost, achieving an overall optimization of the spherical icosahedral grid. Experiments on the four optimized grids (the spring dynamics optimized grid, the Heikes and Randall optimized grid, the spherical centroidal Voronoi tessellations optimized grid and XU optimized grid) demonstrate that the grid area uniformity of our method has been raised by 22.60% of SPRG grid, −1.30% of HR grid, 38.30% of SCVT grid and 38.20% of XU grid, and the grid interval uniformity has been improved by 2.50% of SPRG grid, 2.80% of HR grid, 11.10% of SCVT grid and 11.00% of XU grid. Although the grid uniformity of the proposed method is similar with the HR grid, the smoothness of grid deformation has been enhanced by 79.32% of grid area and 24.07% of grid length. To some extent, the proposed method may be viewed as a novel optimization approach of the spherical icosahedral grid which can improve grid overall uniformity and smoothness of grid deformation.

Metrics for Quality Assessment of a Multiobjective Design Optimization Solution Set

2000 ◽  
Vol 123 (1) ◽  
pp. 18-25 ◽  
Author(s):  
Jin Wu ◽  
Shapour Azarm
Keyword(s):  
Multiobjective Optimization ◽  
Pareto Frontier ◽  
Optimization Methods ◽  
Optimization Method ◽  
Solution Set ◽  
Pareto Solution ◽  
Vibrating Platform ◽  
Pareto Solution Sets ◽  
Multiobjective Design

In this paper, several new set quality metrics are introduced that can be used to evaluate the “goodness” of an observed Pareto solution set. These metrics, which are formulated in closed-form and geometrically illustrated, include hyperarea difference, Pareto spread, accuracy of an observed Pareto frontier, number of distinct choices and cluster. The metrics should enable a designer to either monitor the quality of an observed Pareto solution set as obtained by a multiobjective optimization method, or compare the quality of observed Pareto solution sets as reported by different multiobjective optimization methods. A vibrating platform example is used to demonstrate the calculation of these metrics for an observed Pareto solution set.

scholarly journals Study on Optimization Method of Spatial Structure Characteristics of Peak Forest Landform in Wulingyuan Scenic Area

2020 ◽  
Vol 24 (1) ◽  
pp. 35-44
Author(s):  
Qian Zhang
Keyword(s):  
Spatial Structure ◽  
Optimization Methods ◽  
Optimization Method ◽  
Topographic Analysis ◽  
Structure Characteristics ◽  
Lithological Composition ◽  
Basic Features ◽  
Contour Tree ◽  
Fragmentation Degree

To protect the ecological environment of peak forest landform and maintain its integrity and stability, the optimization method of spatial structure characteristics of peak forest landform in Wulingyuan Scenic Area was studied. By using GIS and digital topographic analysis to study the basic features of sandstone peak forest landform, Wulingyuan peak forest landform and karst peak forest have great differences in lithological composition, weathering resistance is better than Cheltenham Badland landform; by using tree theory to analyze the features of Wulingyuan peak forest landform, according to area weight serialization of contour tree nodes, we can know the depression area. The karstification is stronger than that of the peak forest area, and the surface is relatively fragmented. Based on different landscape indices, the landscape pattern of Wulingyuan peak forest is analyzed. The fragmentation degree of vegetation is lower, and the fragmentation degree of building landscape is first increased, then decreased, and finally intensified. The proportion of artificial landscape decreases year by year and the trend of fragmentation is obvious. Based on the present situation of spatial structure characteristics of Wulingyuan peak forest landform, optimization methods such as combining centralization with decentralization and improving the quality of artificial landscape ecosystem were put forward.

Software suite for determining the tilts of tower-type structures according to terrestrial laser scanning

2020 ◽  
Vol 961 (7) ◽  
pp. 2-7
Author(s):  
A.V. Zubov ◽  
N.N. Eliseeva
Keyword(s):  
Laser Scanning ◽  
Optimization Problems ◽  
Optimization Methods ◽  
User Participation ◽  
Software Suite ◽  
Current State ◽  
Visual Basic For Applications ◽  
Operational Data ◽  
Theoretical Developments

The authors describe a software suite for determining tilt degrees of tower-type structures according to ground laser scanning indication. Defining the tilt of the pipe is carried out with a set of measured data through approximating the sections by circumferences. They are constructed using one of the simplest search engine optimization methods (evolutionary algorithm). Automatic filtering the scan of the current section from distorting data is performed by the method of assessing the quality of models constructed with that of least squares. The software was designed using Visual Basic for Applications. It contains several blocks (subprograms), with each of them performing a specific task. The developed complex enables obtaining operational data on the current state of the object with minimal user participation in the calculation process. The software suite is the result of practical implementing theoretical developments on the possibilities of using search methods at solving optimization problems in geodetic practice.

scholarly journals Target Localization Based on Bistatic T/R Pair Selection in GNSS-Based Multistatic Radar System

2021 ◽  
Vol 13 (4) ◽  
pp. 707
Author(s):  
Yu’e Shao ◽  
Hui Ma ◽  
Shenghua Zhou ◽  
Xue Wang ◽  
Michail Antoniou ◽  
...  
Keyword(s):  
Optimization Methods ◽  
Optimization Method ◽  
Satellite System ◽  
Radar System ◽  
Target Localization ◽  
Computational Load ◽  
Matrix Fusion ◽  
Global Navigation Satellite ◽  
Multistatic Radar ◽  
Combined Algorithm

To cope with the increasingly complex electromagnetic environment, multistatic radar systems, especially the passive multistatic radar, are becoming a trend of future radar development due to their advantages in anti-electronic jam, anti-destruction properties, and no electromagnetic pollution. However, one problem with this multi-source network is that it brings a huge amount of information and leads to considerable computational load. Aiming at the problem, this paper introduces the idea of selecting external illuminators in the multistatic passive radar system. Its essence is to optimize the configuration of multistatic T/R pairs. Based on this, this paper respectively proposes two multi-source optimization algorithms from the perspective of resolution unit and resolution capability, the Covariance Matrix Fusion Method and Convex Hull Optimization Method, and then uses a Global Navigation Satellite System (GNSS) as an external illuminator to verify the algorithms. The experimental results show that the two optimization methods significantly improve the accuracy of multistatic positioning, and obtain a more reasonable use of system resources. To evaluate the algorithm performance under large number of transmitting/receiving stations, further simulation was conducted, in which a combination of the two algorithms were applied and the combined algorithm has shown its effectiveness in minimize the computational load and retain the target localization precision at the same time.

scholarly journals Exploration of Semantic Geo-Object Recognition Based on the Scale Parameter Optimization Method for Remote Sensing Images

2021 ◽  
Vol 10 (6) ◽  
pp. 420
Author(s):  
Jun Wang ◽  
Lili Jiang ◽  
Qingwen Qi ◽  
Yongji Wang
Keyword(s):  
Parameter Optimization ◽  
Scale Parameter ◽  
Human Perception ◽  
Optimization Methods ◽  
Optimization Method ◽  
Initiation Point ◽  
Scale Parameters ◽  
Object Based ◽  
Geographic Object ◽  
Multiresolution Segmentation

Image segmentation is of significance because it can provide objects that are the minimum analysis units for geographic object-based image analysis (GEOBIA). Most segmentation methods usually set parameters to identify geo-objects, and different parameter settings lead to different segmentation results; thus, parameter optimization is critical to obtain satisfactory segmentation results. Currently, many parameter optimization methods have been developed and successfully applied to the identification of single geo-objects. However, few studies have focused on the recognition of the union of different types of geo-objects (semantic geo-objects), such as a park. The recognition of semantic geo-objects is likely more crucial than that of single geo-objects because the former type of recognition is more correlated with the human perception. This paper proposes an approach to recognize semantic geo-objects. The key concept is that a single geo-object is the smallest component unit of a semantic geo-object, and semantic geo-objects are recognized by iteratively merging single geo-objects. Thus, the optimal scale of the semantic geo-objects is determined by iteratively recognizing the optimal scales of single geo-objects and using them as the initiation point of the reset scale parameter optimization interval. In this paper, we adopt the multiresolution segmentation (MRS) method to segment Gaofen-1 images and tested three scale parameter optimization methods to validate the proposed approach. The results show that the proposed approach can determine the scale parameters, which can produce semantic geo-objects.

Comparison between Optimization Method and Experience-Based Method in Soil Conservation

2013 ◽  
Vol 726-731 ◽  
pp. 3811-3817
Author(s):  
Yuan Feng ◽  
Ji Xian Wang
Keyword(s):  
Slope Stability ◽  
Soil Conservation ◽  
Computer Aided Design ◽  
Optimization Methods ◽  
Optimization Method ◽  
Interaction Function ◽  
The Standard Model ◽  
Computer Aided ◽  
Slice Method ◽  
Aided Design

The analysis of the slope stability is important in soil conservation. To analyze the slope stability, optimization methods were coded and compared with the traditional experience-based methods. Furthermore, the results were visualized in the program, so that the user can easily check the results and can designate an area, in which the program seeks the center and radius of the most hazardous slide arc. Moreover, the graphic interaction function was implemented in the program. In addition, the Standard Model One, recommended by ACAD (The Association for Computer Aided Design), was calculated by the program, of which the results (safety factor Ks=0.95~0.96) were smaller than the official recommend value (Ks=1). It is because that the traditional slice method, which neglects the normal stress and shear stress between the slices, was applied for calculation of Ks.

APPLICATION OF THE PUMPKIN POMACE POWDER IN ENRICHED CRACKER TECHNOLOGY

2019 ◽  
Author(s):  
Н.М. ДЕРКАНОСОВА ◽  
И.И. ЗАЙЦЕВА ◽  
А.А. ЕМЕЛЬЯНОВ ◽  
Т.В. ПОНОМАРЕВА ◽  
А.А. СТАХУРЛОВА ◽  
...  
Keyword(s):  
Dietary Fiber ◽  
Optimization Method ◽  
Mathematical Planning ◽  
Chemical Indicators ◽  
Organoleptic Characteristics ◽  
Autolytic Activity ◽  
Physical And Chemical ◽  
Interstate Standard ◽  
Β Carotene

Рассмотрены аспекты применения вторичного продукта сокового производства – выжимок из тыквы, полученных конвективным вакуумным высушиванием при температуре, не превышающей 50°С, в качестве обогащающего пищевыми волокнами сырьевого ингредиента рецептуры крекера. Дана характеристика высушенных выжимок из тыквы сорта Мускатная. Приведены результаты исследования влияния порошка из выжимок тыквы дисперсностью от 63 до 125 мкм на хлебопекарные свойства муки – количество и качество клейковины, автолитическую активность. Обоснование рецептуры крекера с повышенным содержанием пищевых волокон и β-каротина проведено методом математического планирования – полный факторный эксперимент 22 с последующей оптимизацией методом ридж-анализа. Разработана производственная рецептура. Апробация разработанной рецептуры показала, что крекер с выжимками из тыквы в количестве 11,34 г/100 г муки имеет отличительные органолептические характеристики, обусловленные привкусом и ароматом тыквы, по физико-химическим показателям соответствует требованиям межгосударственного стандарта, по составу, г/100 г, пищевых волокон (3,4) и β-каротина (2,9) может быть отнесен к продукту – источнику пищевых волокон с высоким содержанием β-каротина. The aspects of the use of the secondary product of juice production – pumpkin pomace obtained by convection vacuum drying at a temperature not exceeding 50°C, as an enriching raw ingredient of the cracker formulation with food fibers are considered. The characteristics of dried pumpkin pomace of Muscatnaya variety are given. The results of the study of the influence of pumpkin pomace powder dispersion from 63 to 125 microns on the baking properties of flour – the quantity and quality of gluten, autolytic activity are adduced. The substantiation of the cracker formulation with high content of dietary fibers and β-carotene was carried out by the method of mathematical planning – a complete factorial experiment 22 with subsequent optimization method by ridge analysis. The production formulation is developed. Approbation of the developed formulation showed that the cracker with pumpkin extracts – 11,34 g/100 g of flour has distinctive organoleptic characteristics due to the taste and aroma of pumpkin, on physical and chemical indicators meets the requirements of the interstate standard, by composition, g/100 g, dietary fiber (3,4) and β-carotene (2,9) can be attributed to the product – a source of dietary fiber with a high content of β-carotene.

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