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Making a Mechanical Organism Being the fourth in a series of essays on the materials of nature 被引量:1
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作者 Julian F. V. 《Journal of Bionic Engineering》 SCIE EI CSCD 2006年第1期43-58,共16页
Most multicellular organisms can be categorised by two words: hierarchy and composite. The underlying fractal geometry of nature - at least in terms of provision of infrastructure - provides much of the hierarchy, al... Most multicellular organisms can be categorised by two words: hierarchy and composite. The underlying fractal geometry of nature - at least in terms of provision of infrastructure - provides much of the hierarchy, although many materials for which infrastructure is not an integral factor are also strongly hierarchical. Plants can therefore be modelled using recursive computer programs which add structures as the size increases. However, problems with mechanical stability also increase as the structure grows, so the plant changes from deriving stiffness from intevaal pressure to cross-linking the cell wall components permanently. However, this compromises the ability of the plant to grow and repair itself. 展开更多
关键词 Making a Mechanical Organism Being the fourth in a series of essays on the materials of nature
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Applications-Some Influences of Engineering Ideas on Biology Being the fifth in a series of essays on the materials of nature 被引量:1
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作者 Julian F.V.Vincent 《Journal of Bionic Engineering》 SCIE EI CSCD 2006年第2期99-114,共16页
Ideas from engineering have helped the understanding of biological organisms for thousands of years. However, the mechanical aspects of biological materials and structures can, if properly interpreted and analysed, le... Ideas from engineering have helped the understanding of biological organisms for thousands of years. However, the mechanical aspects of biological materials and structures can, if properly interpreted and analysed, lead to a deeper understanding of the biology of organisms. Such an approach, although always current in some form, is nevertheless subject to the vagaries of fashion and the availability of analytical techniques. At present we are in a period of upturn. Areas of interest are deployable structures (applications in aerospace), palaeontology (how little do we need to know in order to create a credible biosphere) and food science (we need a rational approach to the mechanics of food). 展开更多
关键词 Applications-Some Influences of Engineering Ideas on Biology Being the fifth in a series of essays on the materials of nature
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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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Forms of phosphorus and silicon in the natural grain size surface sediments of the southern Bohai Sea 被引量:9
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作者 宋金明 罗延馨 +1 位作者 吕晓霞 李鹏程 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2003年第3期286-292,共7页
The forms of phosphorus and silicon in the natural grain sizes surface sediments of the southern Bohai Sea were studied. In sediments, the organic matter bound form of phosphorus was the main form of transferable phos... The forms of phosphorus and silicon in the natural grain sizes surface sediments of the southern Bohai Sea were studied. In sediments, the organic matter bound form of phosphorus was the main form of transferable phosphorus and ranged from 0.37 μmol/g to 1.57 μmol/g, accounting for 10.7% of the total phosphorus, others were the carbonate bound form, iron manganese oxide bound form and ion exchange able form; the transferable form of phosphorus accounted for 19.2% of the total phosphorus. Silicon’s carbonate bound form was predominant over others among its transferable forms, and content ranged from 1.55 μmol/g to 8.94 μmol/g, accounting for 0.05% of the total silicon; the total amount of transferable silicon forms accounted for only 0.12% of the total silicon. Therefore, 19.2% of the total phosphorus and 0.12% of the total silicon contained in the surface sediments of the southern Bohai Sea could participate in the biogeochemical cycling. 展开更多
关键词 forms of phosphorus and silicon natural grain sizes surface sediments southern Bohai Sea
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2008 Order Form for the Journal of Natural Gas Chemistry 被引量:1
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《Journal of Natural Gas Chemistry》 CAS CSCD 2007年第4期442-442,共1页
关键词 form Order form for the Journal of natural Gas Chemistry
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Forest plant biological diversity in Liangshui Nature Reserve
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作者 张万里 《Journal of Forestry Research》 SCIE CAS CSCD 1999年第4期219-223,共5页
Investigations of forest plant biological diversity were conducted in Liangshui Nature Reserve, Xiaoxing’an Mountains in eastern Heilongjiang Province. Six samples were selected to initiate fieldwork in spring,summer... Investigations of forest plant biological diversity were conducted in Liangshui Nature Reserve, Xiaoxing’an Mountains in eastern Heilongjiang Province. Six samples were selected to initiate fieldwork in spring,summer and autumn. Two samples were added to the whole experiment. Results showed that plant biological diversity in the natural reserve varied with seasons as well as plant growth forms. Generalty the highest diversity values occurred in spring in the communities. Herb species had richer diversity than those of either shrub species or wood species. Species richness, diversity and evenness were quoted in the analysis. 展开更多
关键词 SPECIES DIVERSITY Growth form nature RESERVE
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Preparation and Characteristics of Film Dosage Form Natural Polysaccharides
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作者 Yoshifumi Murata Kyoko Kofuji +1 位作者 Norihisa Nishida Ryosei Kamaguchi 《Pharmacology & Pharmacy》 2011年第3期194-198,共5页
We investigated preparation of film dosage form (FD) from natural polysaccharides using the casting method without organic solvents, heating or pH control. Ferulic acid (FA) and catechin were employed as model compoun... We investigated preparation of film dosage form (FD) from natural polysaccharides using the casting method without organic solvents, heating or pH control. Ferulic acid (FA) and catechin were employed as model compounds incorporated in the FD, and the release profile of each compound from the form was investigated in the limited medium. Film formation was affected by the addition of the model compound to the polysaccharide solution. Rigid FD was obtained with 2% low-molecular-weight alginate (L-ALG;thickness, 65 μm), and it hardened after the addition of 0.5% polygalacturonic acid, although the thickness of the film did not change. The FDs immediately released the model compound, and the forms dissolved in phosphate-buffered saline. FD modification did not affect the FA release rate except in the early stage. FD would be a useful dosage form, especially for preventing or treating localized problems in the oral cavity. 展开更多
关键词 FILM DOSAGE form naturAL Polysaccharide Sodium ALGINATE Ferulic Acid CATECHIN
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2010 Order Form for the Journal of Natural Gas Chemistry
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《Journal of Natural Gas Chemistry》 CAS CSCD 2010年第3期354-354,共1页
Because Elsevier takes care of JNGC's international institutional print subscriptions beginning from 2006,please visit the following website of Elsevier for the international Institutional orders.
关键词 form Order form for the Journal of natural Gas Chemistry 2010
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2012 Order Form for the Journal of Natural Gas Chemistry
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《Journal of Natural Gas Chemistry》 CAS CSCD 2012年第5期I0001-I0001,共1页
Because Elsevier takes care of JNGC’s international institutional print subscriptions beginning from 2006,please visit the following website of Elsevier for the international Institutional orders.http://www.elsevier.... Because Elsevier takes care of JNGC’s international institutional print subscriptions beginning from 2006,please visit the following website of Elsevier for the international Institutional orders.http://www.elsevier.com/locate/jngc 展开更多
关键词 form Order form for the Journal of natural Gas Chemistry
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2006 Order Form for the Journal of Natural Gas Chemistry
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《Journal of Natural Gas Chemistry》 CAS CSCD 2005年第3期191-191,共1页
关键词 form Order form for the Journal of natural Gas Chemistry
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2012 Order Form for the Journal of Natural Gas Chemistry
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《Journal of Natural Gas Chemistry》 CAS CSCD 2012年第4期I0001-I0001,共1页
关键词 form Order form for the Journal of natural Gas Chemistry
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2011 Order Form for the Journal of Natural Gas Chemistry
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《Journal of Natural Gas Chemistry》 CAS CSCD 2011年第5期I0001-I0001,共1页
关键词 form Order form for the Journal of natural Gas Chemistry
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2008 Order Form for the Journal of Natural Gas Chemistry
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《Journal of Natural Gas Chemistry》 CAS CSCD 2008年第1期112-112,共1页
关键词 form Order form for the Journal of natural Gas Chemistry
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2008 Order Form for the Journal of Natural Gas Chemistry
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《Journal of Natural Gas Chemistry》 CAS CSCD 2008年第2期212-212,共1页
关键词 form Order form for the Journal of natural Gas Chemistry
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2005 Order Form for the Journal of Natural Gas Chemistry
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《Journal of Natural Gas Chemistry》 CAS CSCD 2005年第2期127-127,共1页
Annual subscription rate: Businesses and research institutes: US $400.00 for overseas/ RMB 400.00 for Chinese Individuals: US $240.00 for overseas/ RMB 240.00 for Chinese Please subscribe me to the Journal (starting i... Annual subscription rate: Businesses and research institutes: US $400.00 for overseas/ RMB 400.00 for Chinese Individuals: US $240.00 for overseas/ RMB 240.00 for Chinese Please subscribe me to the Journal (starting in 2002): Number of years: Total amount: US $ RMB 展开更多
关键词 form Order form for the Journal of natural Gas Chemistry
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2012 Order Form for the Journal of Natural Gas Chemistry
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《Journal of Natural Gas Chemistry》 CAS CSCD 2012年第1期104-104,共1页
关键词 form Order form for the Journal of natural Gas Chemistry
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2005 Order Form for the Journal of Natural Gas Chemistry
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《Journal of Natural Gas Chemistry》 CAS CSCD 2005年第1期63-63,共1页
关键词 form Order form for the Journal of natural Gas Chemistry
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Effects of the Form Factor and the Force of the Gravity on the Thermal Exchanges by Natural Convection in a Rectangular Cavity Filled with Nanofluid
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作者 L. Eljamali A. Wakif +2 位作者 Z. Boulahia M. Zaydan R. Sehaqui 《Engineering(科研)》 2019年第1期59-73,共15页
Effects of the form factor on natural convection heat transfer and fluid flow in a two-dimensional cavity filled with Al2O3-nanofluid has been analyzed numerically. A model was developed to explain the behavior of nan... Effects of the form factor on natural convection heat transfer and fluid flow in a two-dimensional cavity filled with Al2O3-nanofluid has been analyzed numerically. A model was developed to explain the behavior of nanofluids taking account of the volume fraction φ. The Navier-Stokes equations are solved numerically by alternating an implicit method (Method ADI) for various Rayleigh numbers varies as 103, 104 and 105. The nanofluid used is aluminum oxide with water Pr = 6.2;solid volume fraction φ is varied as 0%, 5% and 10%. Inclination angle Φ varies from 0° to 90° with a step the 15° and the form report varies as R = 0.25, 0.5, 1 and 4. The problem considered is a two-dimensional heat transfer enclosure. The vertical walls are differentially heated;the right is cold when the left is hot. The horizontal walls are assumed to be insulated. The nanofluid in the cavity is considered as incompressible, Newtonian and laminar flow. The nanoparticles are assumed to have a shape and a uniform size. However, it is supposed that the two fluid phases and nanoparticles are in a state of thermal equilibrium and they sink at the same speed. The thermophysical properties of nanofluids are assumed to be constant at the exception of the variation of density in the force of buoyancy, which is based on the approximation of Boussinesq values. 展开更多
关键词 NANOFLUID Heat Transfer THERMAL EXCHANGES natural Convection The FORCE of the GRAVITY form Factor
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一种基于K-means与Close-Form融合的树木图像提取方法 被引量:3
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作者 张怡卓 梁玉亮 +1 位作者 王小虎 于慧伶 《西北林学院学报》 CSCD 北大核心 2019年第2期240-245,共6页
基于图像的树木自动提取是其种类、长势、形态等信息智能化判别的基础,如何实现树木的自动、准确、快速提取是具有实用性的科学问题。在自然场景中,由于图像元素多样、颜色差异大,树木自身存在不规则性,树木提取难度非常大。针对现有的... 基于图像的树木自动提取是其种类、长势、形态等信息智能化判别的基础,如何实现树木的自动、准确、快速提取是具有实用性的科学问题。在自然场景中,由于图像元素多样、颜色差异大,树木自身存在不规则性,树木提取难度非常大。针对现有的图像分割与图像抠图法在树木提取过程中分别存在的误分割与过程复杂所导致的计算量大的问题,提出了一种基于K-means聚类算法优化Close-Form图像抠图的树木提取方法。在少量的标记下,依据颜色线性假设进行最小化代价函数计算,得到图像透明度;对透明度图像依次进行中值滤波、高斯滤波,得到透明度的去噪图像;对滤波后透明度与标准化的图像绿色分量组成二维空间进行K-means二聚类,实现背景与前景对象的准确判定,进而完成自然背景的树木图像提取。为了验证所提方法在不同场景和不同标记下的树木提取有效性,设计了基于K-means图像分割和传统Close-Form抠图方法的比较性试验。结果表明,基于K-means优化Close-Form的树木提取方法解决了传统Close-Form算法在少量标记下图像前景、背景估计不准确问题,克服了图像分割存在的误分类情况,实现了不同自然环境和多目标树木对象的提取。此方法具有对象提取稳定、计算时间快的优点,相对原Close-Form算法用时减少49.98%。 展开更多
关键词 树木图像提取 自然图像抠图 图像分割 Close-form算法 K-MEANS聚类
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Distribution Characteristics and Accumulation Model for the Coal-formed Gas Generated from Permo-Carboniferous Coal Measures in Bohai Bay Basin, China: A Review 被引量:4
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作者 JIANG Youlu HU Hongjin +1 位作者 Jon GLUYAS ZHAO Kai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第6期1869-1884,共16页
Coal-formed gas generated from the Permo-Carboniferous coal measures has become one of the most important targets for deep hydrocarbon exploration in the Bohai Bay Basin,offshore eastern China.However,the proven gas r... Coal-formed gas generated from the Permo-Carboniferous coal measures has become one of the most important targets for deep hydrocarbon exploration in the Bohai Bay Basin,offshore eastern China.However,the proven gas reserves from this source rock remain low to date,and the distribution characteristics and accumulation model for the coal-formed gas are not clear.Here we review the coal-formed gas deposits formed from the Permo-Carboniferous coal measures in the Bohai Bay Basin.The accumulations are scattered,and dominated by middle-small sized gas fields,of which the proven reserves ranging from 0.002 to 149.4×108 m3 with an average of 44.30×108 m3 and a mid-point of 8.16×108 m3.The commercially valuable gas fields are mainly found in the central and southern parts of the basin.Vertically,the coal-formed gas is accumulated at multiple stratigraphic levels from Paleogene to Archaeozoic,among which the Paleogene and PermoCarboniferous are the main reservoir strata.According to the transporting pathway,filling mechanism and the relationship between source rocks and reservoir,the coal-formed gas accumulation model can be defined into three types:"Upward migrated,fault transported gas"accumulation model,"Laterally migrated,sandbody transported gas"accumulation model,and"Downward migrated,sub-source,fracture transported gas"accumulation model.Source rock distribution,thermal evolution and hydrocarbon generation capacity are the fundamental controlling factors for the macro distribution and enrichment of the coal-formed gas.The fault activity and the configuration of fault and caprock control the vertical enrichment pattern. 展开更多
关键词 distribution characteristics of natural gas accumulation model coal-formed gas Permo-Carboniferous coal measures Bohai Bay Basin
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