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Determination of Main Design Indicators of Patrol Road in Nature Reserves
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作者 Hongbo LIU Shuangbei ZENG 《Asian Agricultural Research》 2023年第8期49-51,共3页
In principle,nature reserves are managed and controlled according to the core area and the general control area.At present,there is no relevant design specification for the design system of patrol road in various prot... In principle,nature reserves are managed and controlled according to the core area and the general control area.At present,there is no relevant design specification for the design system of patrol road in various protected areas.This paper analyzed the factors to be considered in determining the grade,horizontal and vertical design indicators,and cross section indicators of the patrol road in the protected area,and came up with the corresponding design indicators and parameters,so as to provide a certain reference for the subsequent patrol road design. 展开更多
关键词 nature reserves Patrol road design indicators Road design
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Research on Products Design of Low-carbon Tourism Development in Nature Reserve——A Case Study of Guangxi Longhu Mountain Scenic Area in China
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作者 廖钟迪 《Journal of Landscape Research》 2011年第4期65-67,75,共4页
After analyzing three misunderstandings about eco-tourism development,the paper pointed out that low-carbon tourism based on control of carbon emission had larger implementation space,which could be applied in all typ... After analyzing three misunderstandings about eco-tourism development,the paper pointed out that low-carbon tourism based on control of carbon emission had larger implementation space,which could be applied in all types of tourist destinations,with strong operability and the effectiveness evaluation of which was easier to be quantized.On this basis,low-carbon development thought of nature reserve was proposed by taking Guangxi Longhu Mountain Nature Reserve as the example.Through introduction of general situation of low-carbon tourist resources in Longhu Mountain,it analyzed necessity to design low-carbon tourist products in Longhu Mountain Nature Reserve,designed low-carbon tourist activities according to resources characteristics,and proposed five distinctive low-carbon tour routes in light with different tourists markets.Finally,some relevant suggestions on development had been put forward. 展开更多
关键词 Longhu MOUNTAIN nature RESERVE Low-carbon TOURISM PRODUCTS design
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Super-Boost变换器的工作模式及输出纹波电压分析
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作者 皇金锋 韩梦祺 《电源学报》 CSCD 北大核心 2024年第1期11-21,共11页
Super-Boost变换器代替传统的充、放电模块可大大减小电源的质量和体积,提高其功率密度,因此在空间电力系统中具有广阔的应用前景。但由于Super-Boost变换器有多个功率元件,且存在电感电流反向流动特性,导致其供能模式及输出纹波电压较... Super-Boost变换器代替传统的充、放电模块可大大减小电源的质量和体积,提高其功率密度,因此在空间电力系统中具有广阔的应用前景。但由于Super-Boost变换器有多个功率元件,且存在电感电流反向流动特性,导致其供能模式及输出纹波电压较传统Boost变换器复杂。为了给Super-Boost变换器的分析和设计提供正确的理论指导,对Super-Boost变换器供能模式及输出纹波电压进行了深入研究。研究发现,电感L_(1)和L_(2)均存在连续导电模式、伪连续导电模式和伪断续导电模式等工作模式,建立各工作模式的临界电感和输出纹波电压解析数学模型,探讨峰值电流与电感间的关系,得到了满足设计要求的最小电容和最小电感,据此给出了变换器参数设计方法,实验结果验证了理论分析的正确性。 展开更多
关键词 super-Boost变换器 工作模式 临界电感 输出纹波电压 参数设计
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Fundamental Issues Towards Unified Design Theory of Recycled and Natural Aggregate Concrete Components 被引量:1
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作者 Jianzhuang Xiao Kaijian Zhang +2 位作者 Tao Ding Qingtian Zhang Xuwen Xiao 《Engineering》 SCIE EI CAS CSCD 2023年第10期188-197,共10页
In the past 20 years,recycled aggregate concrete(RAC),as a type of low-carbon concrete,has become a worldwide focus of research.However,the design methodology for RAC structural components remains a challenge.Conseque... In the past 20 years,recycled aggregate concrete(RAC),as a type of low-carbon concrete,has become a worldwide focus of research.However,the design methodology for RAC structural components remains a challenge.Consequently,demands for a unified design of natural aggregate concrete(NAC)and RAC components have been presented.Accordingly,this study analyses the necessity of a unified design theory and provides an in-depth demonstration of the strength determination,compressive constitutive relationship,and design method of concrete components.The coefficient of variation of RAC strength is found to be generally higher than that of NAC strength.The compressive and tensile strengths of RAC can be defined and determined using the same method as that used for NAC.The uniaxial compressive constitutive relationship between NAC and RAC has a unified mathematical expression.However,the elastic modulus of RAC decreases,and its brittleness exhibits an increasing trend compared with that of NAC.Finally,to unify the design formulae of RAC and NAC components for bearing capacity,modification factors for RAC components are proposed considering safety and reliability.Additionally,the feasibility of the proposed unified time-dependent design theory is demonstrated in terms of conceptual design and structural measures considering the effects of strength degradation and reinforcement corrosion.It is believed that this study enriches and develops the basic theory of concrete structures. 展开更多
关键词 Recycled aggregate concrete(RAC) natural aggregate concrete(NAC) Strength determination Constitutive relation Reliability Unified design theory
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An Innovative Methodology of Product Design from Nature 被引量:7
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作者 Hui-I Wen Shu-jun Zhang +1 位作者 Kevin Hapeshi Xiao-feng Wang 《Journal of Bionic Engineering》 SCIE EI CSCD 2008年第1期75-84,共10页
Nature is an information sourcebook of behaviour, function, colour and shape which can inspire visual design and invention. Studying the form and functional characteristics of a natural object can provide inspiration ... Nature is an information sourcebook of behaviour, function, colour and shape which can inspire visual design and invention. Studying the form and functional characteristics of a natural object can provide inspiration for product design and help to improve the marketability of manufactured products. The inspiration can be triggered either by direct observation or captured by three-dimensional (3D) digitising techniques to obtain superficial information (geometry and colour). An art designer often creates a concept in the form of a two-dimensional (2D) sketch while engineering methods lead to a point cloud in 3D. Each has its limitations in that the art designer commonly lacks the knowledge to build a final product from a 2D sketch and the engi- neering designer's 3D point clouds may not be very beautiful. We propose a method for Product Design from Nature (PDN), coupling aesthetic intent and geometrical characteristics, exploring the interactions between designers and nature's systems in PDN. We believe that this approach would considerably reduce the lead time and cost of product design from nature. 展开更多
关键词 bio-inspiration design conceptual design designer sketch inspiration forms aesthetic design from nature
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Robust design of natural laminar flow supercritical airfoil by multi-objective evolution method 被引量:5
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作者 赵轲 高正红 黄江涛 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2014年第2期191-202,共12页
Abstract A transonic, high Reynolds number natural laminar flow airfoil is designed and studied. The γ-θ transition model is combined with the shear stress transport (SST) k-w turbulence model to predict the trans... Abstract A transonic, high Reynolds number natural laminar flow airfoil is designed and studied. The γ-θ transition model is combined with the shear stress transport (SST) k-w turbulence model to predict the transition region for a laminar-turbulent boundary layer. The non-uniform free-form deformation (NFFD) method based on the non-uniform rational B-spline (NURBS) basis function is introduced to the airfoil parameterization. The non-dominated sorting genetic algorithm-II (NSGA-II) is used as the search algo- rithm, and the surrogate model based on the Kriging models is introduced to improve the efficiency of the optimization system. The optimization system is set up based on the above technologies, and the robust design about the uncertainty of the Mach number is carried out for NASA0412 airfoil. The optimized airfoil is analyzed and compared with the original airfoil. The results show that natural laminar flow can be achieved on a supercritical airfoil to improve the aerodynamic characteristic of airfoils. 展开更多
关键词 non-uniform free-form deformation (NFFD) method transition model natural laminar flow (NFL) airfoil supercritical airfoil non-dominated sorting geneticalgorithm II (NSGA-II) robust design surrogate model
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Conception and Planning of Campus Landscape Combined with Nature Education Based on Species Survey:A Case Study of North China University of Technology
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作者 LI Tongyu WANG Xiaobo 《Journal of Landscape Research》 2023年第2期6-10,共5页
From the perspective of habitats and species diversity in biodiversity,the species and richness of plants and animals in the campus green spaces of North China University of Technology were surveyed comprehensively by... From the perspective of habitats and species diversity in biodiversity,the species and richness of plants and animals in the campus green spaces of North China University of Technology were surveyed comprehensively by natural observation and field investigation.A total of 118 species of plants and 70species of animals were investigated.The relationship between plants and animals on the campus was analyzed qualitatively.Based on this,the richness of species in the plots suitable for natural education in the sites was investigated and analyzed,and the situations in different seasons were compared to plan natural education areas and trails.In addition,the ways to increase the biodiversity of the sites,the connection between habitats and landscape elements,and the setting of relevant landscape sites were discussed,and it was proposed to integrate more natural education methods to attract people to carry out natural education of biodiversity in the university campus with a learning atmosphere. 展开更多
关键词 University campus BIODIVERSITY natural education Landscape design
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A symmetric substructuring method for analyzing the natural frequencies of conical origami structures
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作者 Chenhao Lu Yao Chen +2 位作者 Weiying Fan Jian Feng Pooya Sareh 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第3期203-210,共8页
Conical origami structures are characterized by their substantial out-of-plane stiffness and energy-absorptioncapacity.Previous investigations have commonly focused on the static characteristics of these lightweight s... Conical origami structures are characterized by their substantial out-of-plane stiffness and energy-absorptioncapacity.Previous investigations have commonly focused on the static characteristics of these lightweight struc-tures.However,the efficient analysis of the natural vibrations of these structures is pivotal for designing conicalorigami structures with programmable stiffness and mass.In this paper,we propose a novel method to analyzethe natural vibrations of such structures by combining a symmetric substructuring method(SSM)and a gener-alized eigenvalue analysis.SSM exploits the inherent symmetry of the structure to decompose it into a finiteset of repetitive substructures.In doing so,we reduce the dimensions of matrices and improve computationalefficiency by adopting the stiffness and mass matrices of the substructures in the generalized eigenvalue analysis.Finite element simulations of pin-jointed models are used to validate the computational results of the proposedapproach.Moreover,the parametric analysis of the structures demonstrates the influences of the number of seg-ments along the circumference and the radius of the cone on the structural mass and natural frequencies of thestructures.Furthermore,we present a comparison between six-fold and four-fold conical origami structures anddiscuss the influence of various geometric parameters on their natural frequencies.This study provides a strategyfor efficiently analyzing the natural vibration of symmetric origami structures and has the potential to contributeto the efficient design and customization of origami metastructures with programmable stiffness. 展开更多
关键词 natural structural vibration Origami design Group theory Symmetric substructuring method(SSM) Generalized eigenvalue analysis
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Waterfront Embankment Landscape Design “Modeling after the Nature”
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作者 WANG Yicheng CHEN Xiaogang 《Journal of Landscape Research》 2014年第4期13-15,18,共4页
The concept of "modeling after the nature" was introduced into embankment landscape design,types of embankment landscapes analyzed,and landscape design concepts of urban waterfront embankment proposed,to ref... The concept of "modeling after the nature" was introduced into embankment landscape design,types of embankment landscapes analyzed,and landscape design concepts of urban waterfront embankment proposed,to reflect and coordinate human-nature relationship,and achieve the harmony between human society and natural environment. 展开更多
关键词 Modeling after the nature EMBANKMENT Landscape design
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The Design Characteristics of Innovative Nature-Inspired Architecture for Building Design
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作者 Dongil Choe Kanggeun Park 《Journal of Civil Engineering and Architecture》 2019年第5期309-329,共21页
This paper analyses what is the concept of nature inspiration in relation to the innovative design of buildings, and the design characteristics of innovative design as well as the harmonious interactions of the past a... This paper analyses what is the concept of nature inspiration in relation to the innovative design of buildings, and the design characteristics of innovative design as well as the harmonious interactions of the past and the future in urban regeneration. This is with the aim of determining how to acquire inspirations from nature, and how to subsequently apply the visual or conceptual nature-inspired designs. Such nature-inspired designs seek to exploit the new concepts of biophilic design, such as bio-eco-friendly sustainable processes, creative designs, and systems which can be used to improve the urban environment. The goal of this research is to uncover out ways by which to apply new ideas inspired by nature for an innovative building design. 展开更多
关键词 nature INSPIRATION INNOVATIVE design nature-inspired biophilic design URBAN environment
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Latent Challenges in the Human-Nature Relationship for Sustainable Design and Planning
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作者 Sanaz Shobeiri 《Journal of Civil Engineering and Architecture》 2018年第7期471-482,共12页
In the global context, the relationship between human beings and nature has been discussed in various fields of study. This paper introduced three of the important challenges in this relationship, which have, thus far... In the global context, the relationship between human beings and nature has been discussed in various fields of study. This paper introduced three of the important challenges in this relationship, which have, thus far, been only partially or implicitly acknowledged in design and planning. The aim was to elucidate the key disregarded and neglected aspects in the human-nature relationship that need to be considered in different phases of the design and planning of future projects. This paper will thus inform the designers and planners about the previously overlooked but important challenges in the human-nature relationship, which must be moved to the foreground of the design and planning processes. These challenges include the definition of the term “nature”, the reciprocal effects among scales and adhering to or going beyond environmental sustainability. As the main conclusion, the paper shows how these challenges can improve the mutually supportive interaction between human beings and nature in the field of design and planning. Specifically speaking, the paper discussed how to convert the overlooked challenges in the human-nature relationship into potentials in the design and planning process. The main applied methods for this paper were a review of the related literature and the appropriate analysis. 展开更多
关键词 Human beings nature CHALLENGES design PLANNING sustainability.
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Design With Nature: The Practice and Theory of Two Chinese Intellectual Architects of the Eighth Century
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作者 Shimeng Sun 《Sociology Study》 2014年第11期925-937,共13页
An old tradition of designing with nature had existed for thousands of years in ancient China. In order to achieve ideal living environment, people believed that they should use, repair, and improve the nature in an a... An old tradition of designing with nature had existed for thousands of years in ancient China. In order to achieve ideal living environment, people believed that they should use, repair, and improve the nature in an active but abstemious way, and a complete system of design theories and techniques gradually developed. The intellectual architects, in particular, pioneered the practical and theoretical developments, especially those in Tang dynasty made extraordinary contributions. Among them, Yuan lie (元结) and Liu Zongyuan (柳宗元) were particularly outstanding. They had different experiences but similar achievements in Yongzhou area, which was a remote, less-developed region but with beautiful landscapes. In this paper, the planning and design practices of these two intellectual architects were examined and compared. Their principles and methods of Design With Nature were summarized. Also, the historical influence of their works and its contemporary value were briefly discussed at last. 展开更多
关键词 design With nature intellectual architects Liu Zongyuan Yuan lie Yongzhou
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Seeking the Humanities in the Nature——The Planning and Design of Fuxi Park in Yangcheng
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作者 Lin Mofei Huo Dan 《中外建筑》 2010年第9期88-90,共3页
关键词 人文学科 计划编制 建筑设计 设计方案
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On the Design Pattern for Improving Urban Living Environment with Regional Natural Resources—By Studying Cases of British Architect Richard Rogers
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作者 苏阳 《Journal of Landscape Research》 2012年第1期30-31,34,共3页
Through discussing effective utilization of regional natural resources under the background of globalization,combining with Richard Rogers' typical architectural and urban design works,this study analyzes his desi... Through discussing effective utilization of regional natural resources under the background of globalization,combining with Richard Rogers' typical architectural and urban design works,this study analyzes his design concepts of using regional natural resources from the perspectives of overall balance between architecture and natural environment,architectural function and detail control,application of proper technologies and new materials,then proposes a modern design pattern to create a better urban living environment by integrating regional natural resources and modern architectural technology. 展开更多
关键词 RICHARD ROGERS Utilization of natural resources Environment improvement ARCHITECTURAL technology design pattern
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Planning and Design of Zhengzhou Forest Park Based on Natural Ecological Experience 被引量:2
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作者 TANG Zhenxing CHEN Qunyang 《Journal of Landscape Research》 2013年第5期27-30,共4页
Through summarizing and analyzing planning objectives, landscape division and natural ecological experience planning of Zhengzhou Forest Park, the authors discussed the application of human-nature harmony in the plann... Through summarizing and analyzing planning objectives, landscape division and natural ecological experience planning of Zhengzhou Forest Park, the authors discussed the application of human-nature harmony in the planning, stressed citizens' needs for experiencing natural ecological environment, and tried to build Zhengzhou Forest Park with picturesque scenery, complete facilities, and harmonious human-nature coexistence. 展开更多
关键词 LANDSCAPE architecture naturAL ECOLOGICAL EXPERIENCE FOREST PARK Planning and design
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Porous structures of natural materials and bionic design 被引量:1
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作者 张建忠 汪久根 马家驹 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第10期1095-1099,共5页
This investigation and morphology analysis of porous structure of some kinds of natural materials such as chicken eggshell, partridge eggshell, pig bone, and seeds of mung bean, soja, ginkgo, lotus seed, as well as th... This investigation and morphology analysis of porous structure of some kinds of natural materials such as chicken eggshell, partridge eggshell, pig bone, and seeds of mung bean, soja, ginkgo, lotus seed, as well as the epidermis of apples, with SEM (Scanning Electronic Microscope) showed that natural structures’ pores can be classified into uniform pores, gradient pores and multi pores from the viewpoint of the distribution variation of pore density, size and geometry. Furthermore, an optimal design of porous bearings was for the first time developed based on the gradient configuration of natural materials. The bionic design of porous structures is predicted to be widely developed and applied in the fields of materials and mechanical engineering in the future. 展开更多
关键词 natural materials Porous structure Bionic design SEM
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Study on the Optimization for Design of Indoor Natural Ventilation and Lighting Based on Passive Design Measurements 被引量:1
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作者 Jian-Hua Ding Ye-Hao Song Tian-Yu Xi 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第4期24-29,共6页
Based on the current indoor natural ventilation and lighting in the space of traditional residential buildings,this paper starts from the passive-design optimization of the spatial natural ventilation and lighting,and... Based on the current indoor natural ventilation and lighting in the space of traditional residential buildings,this paper starts from the passive-design optimization of the spatial natural ventilation and lighting,and makes quantitative evaluation on the quality of current interior natural ventilation and lighting for two typical residential buildings by three indexes,including wind speed,static wind area ratio and satisfaction ratio about minimum lighting coefficient. Based on that, this paper conducts the passive design optimization, and establishes the quantitative association and reevaluation among the passive reformation design, natural ventilation,and lighting environmental quality,proposing the general strategy for the existing residential buildings to respond to the passive reformation design of the natural ventilation and lighting. The special reconstruction of core functionary space of integration of "the living room + dining room + partial space"is researched,and the redesign for the optimization and replacement of both indoor and outdoor enclosure parts is explored,which is expected to provide practical exploration on the strategies for passive construction of spatial natural environmental quality within a large number of highly-energy-consumed residential buildings in China,as well as the green design of residential buildings. 展开更多
关键词 existing residential buildings natural ventilation and lighting green transformation passive design OPTIMIZATION
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Optimization design of foundation excavation for Xiluodu super-high arch dam in China 被引量:7
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作者 Qixiang Fan Shaowu Zhou Ning Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第2期120-135,共16页
With better understanding of the quality and physico-mechanical properties of rocks of dam foundation,and the physico-mechanical properties and structure design of arch dam in association with the foundation excavatio... With better understanding of the quality and physico-mechanical properties of rocks of dam foundation,and the physico-mechanical properties and structure design of arch dam in association with the foundation excavation of Xiluodu arch dam,the excavation optimization design was proposed for the foundation surface on the basis of feasibility study.Common analysis and numerical analysis results demonstrated the feasibility of using the weakly weathered rocks III1and III2as the foundation surface of super-high arch dam.In view of changes in the geological conditions at the dam foundation along the riverbed direction,the design of extending foundation surface excavation area and using consolidating grouting and optimizing structure of dam bottom was introduced,allowing for harmonization of the arch dam and foundation.Three-dimensional(3D)geomechanics model test and fi nite element analysis results indicated that the dam body and foundation have good overload stability and high bearing capacity.The monitoring data showed that the behaviors of dam and foundation correspond with the designed patterns in the construction period and the initial operation period. 展开更多
关键词 super-high arch dam Foundation surface Optimization design Stability analysis
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Lattice design and optimization of the SSRF storage ring with super-bends 被引量:1
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作者 田顺强 姜伯承 +2 位作者 周巧根 冷用斌 赵振堂 《Nuclear Science and Techniques》 SCIE CAS CSCD 2014年第1期6-11,共6页
In the near future,the Phase-Ⅱ beamline project of Shanghai Synchrotron Radiation Facility(SSRF)will be implemented and some dipoles in the storage ring will be replaced by high field dipoles(super-bend),so as to lea... In the near future,the Phase-Ⅱ beamline project of Shanghai Synchrotron Radiation Facility(SSRF)will be implemented and some dipoles in the storage ring will be replaced by high field dipoles(super-bend),so as to leave room for short straight sections.In this way,the brightness of the hard x-ray emitted from the super-bends can be enhanced,and more insertion devices can be installed.In this paper,super-bends of two lengths are discussed and the corresponding lattices are presented. 展开更多
关键词 上海同步辐射装置 储存环 弯曲 优化 光源 设计 SSRF 硬X射线
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Scientific Value of the Fenlong Tillage Erupting Super "Natural Forces" and Its Global Application
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作者 Wei Benhui 《Meteorological and Environmental Research》 CAS 2018年第6期79-83,共5页
The concept of " natural forces" is proposed in farming field for the first time,and the core theory of Fenlong tillage is illustrated. This tillage method provides " super plough layer" and "... The concept of " natural forces" is proposed in farming field for the first time,and the core theory of Fenlong tillage is illustrated. This tillage method provides " super plough layer" and " super groundwater reservoir" by the machine,including six vertical spiral drills,can smash the soil vertically,without disorganizing soil layer. And this tillage method releases five " natural forces" with infinite space and time,including natural soil activation forces,natural fertility forces,natural water control forces,natural environment improvement forces,and natural river driving forces by activating various land resources. Fenlong tillage can significantly increase the source of high-quality food for human,and solve the problem of natural disasters by natural forces curing itself. It is proposed that the implementation of the " six key projects" by the " natural forces" of Fenlong tillage can solve the deep problems in China. The researchers suggest establishing Fenlong tillage great science engineering which could solve the problem of harmonious symbiosis between man and nature. The present results indicate that Fenlong tillage erupts super natural forces with infinite space and time,which can be used as a deep tillage practice to maintain the natural and environmental beauty of the earth forever. 展开更多
关键词 Fenlong tillage super plough layer super groundwater reservoir natural forces of Fenlong tillage Fenlong tillage great science engineering
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