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Design of research platform on telerobot system based on virtual reality technology 被引量:2
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作者 陈俊杰 黄惟一 +2 位作者 宋爱国 奚维旸 林纯 《Journal of Southeast University(English Edition)》 EI CAS 2004年第1期80-84,共5页
A design strategy for a research platform of a telepresence telerobot system based on virtual reality technology is put forward. The design frame of the system is described, and its important core techniques are descr... A design strategy for a research platform of a telepresence telerobot system based on virtual reality technology is put forward. The design frame of the system is described, and its important core techniques are described. An octrees data structure is utilized to build kinematic and dynamic modeling of the virtual simulation environment, Delphi+OpenGL+3DS MAX are adopted to carry through the virtual modeling and visible simulation exploitation of the slave-robot and its environment. Photo-correction is adopted to correct positioning deviation of the virtual geometric model and modeling errors. The cost of software and hardware equipment for the research platform realized is low. The master/slave robot (manipulator) system and all software in the system were designed and manufactured by our research group. The performance of the system has reached the level required for research. An indispensable experiment base is provided for the research of a telepresence telerobot system based on virtual reality technology. 展开更多
关键词 Computer simulation Computer software Data structures MANIPULATORS Remote control Virtual reality
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论高职物业管理专业T型人才培养模式的构建 被引量:3
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作者 沈殿示 《教育与职业》 北大核心 2008年第6期57-58,共2页
目前我国的高职物业管理人才培养模式虽然各具特色,但却难以兼顾岗位针对性和职业适应性。按T型人才培养模式构建的T型能力目标和课程体系,能较好地兼顾岗位针对性和适应性,更好地适应当前就业和日后发展的需要,且能兼容当前各种不... 目前我国的高职物业管理人才培养模式虽然各具特色,但却难以兼顾岗位针对性和职业适应性。按T型人才培养模式构建的T型能力目标和课程体系,能较好地兼顾岗位针对性和适应性,更好地适应当前就业和日后发展的需要,且能兼容当前各种不同的培养方式。 展开更多
关键词 高职物业管理 T型人才 “树”型课程结构体系
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Analysis of Genetic Structure of Natural Populations of Castanopsis fargesii by RAPDs 被引量:12
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作者 朱其慧 潘惠新 +3 位作者 诸葛强 尹佟明 邹惠渝 黄敏仁 《Acta Botanica Sinica》 CSCD 2002年第11期1321-1326,共6页
Genetic diversity and population genetic structure in 188 individuals from five natural populations of Castampsis fargesii Franch. were studied by RAPD markers. Three hundred and eighty-five loci were identified with ... Genetic diversity and population genetic structure in 188 individuals from five natural populations of Castampsis fargesii Franch. were studied by RAPD markers. Three hundred and eighty-five loci were identified with 41 oligonucleotide primers, out of which 157 loci were polymorphic and accounted for 40.78% of total genetic diversity at species level. Shannon's indices of diversity (I) and Nei's gene diversity ( h) were 0.459 7 and 0.296 at the species level, respectively. The result showed that genetic variation of C. fargesii populations mainly existed within populations. Genetic differentiation (Hsp-hpop)/Hsp estimated with Shannon's index of diversity and coefficient of gene differentiation (Gst) were 0.047 6 and 0.042 9 respectively, which were confirmed by the analysis of molecular variance (AMOVA). Therefore, it is apparent that within-population variation accounted for 94.97% and among-populations variation accounted for only 5.03% of the total genetic diversity. AMOVA also indicated that there was significant differentiation among populations as well as among individuals within a population. 展开更多
关键词 Castanopsis fargesii natural populations RAPD genetic structure
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Analysis on Fuji Apple Tree Structures and Related Factors under Different Pruning Modes 被引量:1
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作者 郝婕 索相敏 +4 位作者 李学营 魏亮 王献革 鄢新民 冯建忠 《Agricultural Science & Technology》 CAS 2017年第12期2528-2531,2535,共5页
To determine the correlations between the tree structuresof Fuji apple with different pruning modes and each factor, the data about 3 tree structures which were free spindle short shoot, free spindle long shoot and sl... To determine the correlations between the tree structuresof Fuji apple with different pruning modes and each factor, the data about 3 tree structures which were free spindle short shoot, free spindle long shoot and slenderspindle short shoot in Xingtang County of Hebai Province were investigated, then by SPSS anal- ysis, the correlations between the taperingness and each growth factor of inserted small branch were compared. The results showed that the taperingness of central trunk of free spindle dwarf-shoot Fuji apple treeshad negative correlations with each factor of inserted small branch, while the taperingness of central trunk of free spin- dle long-shoot Fuji apple treeshad positive correlations with each factor of inserted small branch, the taperingness of central trunk of slenderspindle short-shootFuji ap- ple treeshad negative correlation with total thickness of inserted small branch, but had positive correlations with other factors. This study can provide a scientifictheo- retical basis for the pruning technology of high-density planting trees grafting by dwarfing self-rooted rootstock. 展开更多
关键词 PRUNING Fuji apple Tree structures Analysis of related factors
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Vegetative Storage Proteins in Meliaceae 被引量:7
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作者 田维敏 吴继林 +1 位作者 郝秉中 胡正海 《Acta Botanica Sinica》 CSCD 2002年第2期242-245,共4页
采用光学和电子显微镜技术及SDS_PAGE研究了营养贮藏蛋白质 (VSPs)在楝科树木中的分布和超微结构 ;并采用免疫印迹技术 ,以大叶桃花心木 (SwieteniamacrophyllaKing)的 2 1kDVSP的抗血清检测楝科树木VSPs的免疫相关性。结果表明 ,在桃... 采用光学和电子显微镜技术及SDS_PAGE研究了营养贮藏蛋白质 (VSPs)在楝科树木中的分布和超微结构 ;并采用免疫印迹技术 ,以大叶桃花心木 (SwieteniamacrophyllaKing)的 2 1kDVSP的抗血清检测楝科树木VSPs的免疫相关性。结果表明 ,在桃花心木亚科 (Swietenioideae)的树木中普遍存在VSPs ,但楝亚科 (Melioidae)仅部分属的树木有VSPs而椿亚科 (Cedreloideae)树木没有VSPs。VSPs在同一属树木中的分布是一致的。桃花心木亚科和楝亚科树木之间的VSPs几乎没有免疫相关性 ,但是在桃花心木亚科中 ,VSPs具有相对高的同源性。楝科树木VSPs的超微结构存在一定程度的差异 ,这可能与VSPs的种类不同有关。VSPs的分布。 展开更多
关键词 vegetative storage proteins ULTRASTRUCTURE immuno-correlation MELIACEAE
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知识经济时代我国农业信息通才的培养探讨
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作者 郑威 孙东发 《安徽农业科学》 CAS 北大核心 2005年第8期1552-1555,共4页
在前人研究的基础上,笔者对知识经济时代农业科技信息通才的培养目标、素质要求和培养途径进行了分析研究,认为知识经济时代农业信息通才是“一专多能”的复合型人才,而不只是懂某一专业的专门人才;在培养目标上是培养组织管理人才、信... 在前人研究的基础上,笔者对知识经济时代农业科技信息通才的培养目标、素质要求和培养途径进行了分析研究,认为知识经济时代农业信息通才是“一专多能”的复合型人才,而不只是懂某一专业的专门人才;在培养目标上是培养组织管理人才、信息研究与教育人才、信息咨询人才、信息搜集整理人才、农业科技翻译人才、信息工程技术人才、信息应用推广人才。农业信息通才应具备“树”型知识结构“,树根”是农业科学知识“,树干”是外语和图书信息知识,而“分枝”是具有与做好本职工作相关的其他学科知识及现代信息手段的应用知识,即在博专相济的前提下,对工种的主学科知识尽可能深专,而对本职工作相关的学科知识要求越广博越好,此所谓“根深、干粗、叶茂”。农业信息通才的培养途径必须是全方位、多学科、多层次、系统化的,在教育方式上,强调正规教育与继续教育相结合,高、中、低层次相结合;在有条件的农业院校,增设农业信息管理专业,在课程设置上,除公共课外,农业基础课、信息理论、计算机课程的比例基本接近1∶1∶1,着重培养信息技能,既重视计算机应用能力和网络技术的培养,也重视翻译、写作能力的培养。 展开更多
关键词 知识经济时代 农业信息业 信息通才 培养目标 素质 培养途径 “树”型知识结构
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Controllable Electrochemical Synthesis of Silver Dendritic Nanostructures and Their SERS Properties 被引量:1
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作者 洪勋 王冠中 +2 位作者 王颖 祝巍 沈小双 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第5期596-602,622,共8页
Ag dendritic nanostructures were synthesized on fluorine-doped tin oxide covered glass sub- strates by the electrodeposition method. Results demonstrate that the size, diameter, crys- tallinity, and branch density of ... Ag dendritic nanostructures were synthesized on fluorine-doped tin oxide covered glass sub- strates by the electrodeposition method. Results demonstrate that the size, diameter, crys- tallinity, and branch density of the Ag dendrites can be controlled by the applied potential, the surfactants and the concentration of AgNO3. Three kinds of typical silver dendrites were applied as substrates of the surface enhanced Raman scattering (SERS) and one of them was able to clearly detect rhodamine 6G concentrations up to 0.1 nmol/L. The differences of the SERS spectra at these Ag dendrites confirmed that the shapes and interparticle spacings have great effect on Raman enhancement, especially the interparticle spacings. 展开更多
关键词 SILVER Dendritic nanostructure ELECTRODEPOSITION Surface enhanced Raman scattering
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Listless zerotree image compression algorithm 被引量:2
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作者 LIAN Jing WANG Ke 《Optoelectronics Letters》 EI 2006年第5期376-378,395,共4页
In this paper,an improved zerotree structure and a new coding procedure are adopted,which improve the reconstructed image qualities. Moreover, the lists in SPIHT are replaced by flag maps, and lifting scheme is adopte... In this paper,an improved zerotree structure and a new coding procedure are adopted,which improve the reconstructed image qualities. Moreover, the lists in SPIHT are replaced by flag maps, and lifting scheme is adopted to realize wavelet transform, which lowers the memory requirements and speeds up the ceding process. Experimental results show that the algorithm is more effective and efficient compared with SPIHT. 展开更多
关键词 图象压缩算法 结构 图象重建 小波传输
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Anatomy of Different Ages of Streblus asper Leaves and Their Drought Resistance 被引量:4
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作者 Mingyuan ZHAO Shijun HONG +1 位作者 Chunmei WANG Yong YUN 《Agricultural Science & Technology》 CAS 2017年第1期87-92,共6页
The leaf thickness, stratum corneum thickness, epidermis thickness, palisade tissue thickness and sponge tissue thickness of Streblus asper leaves at different ages were observed by using paraffin section technology a... The leaf thickness, stratum corneum thickness, epidermis thickness, palisade tissue thickness and sponge tissue thickness of Streblus asper leaves at different ages were observed by using paraffin section technology and optical microscopic observation to explore the anatomic adaptive response mechanism to drought stress, also to provide a theoretical basis for S. asper introduction. The results showed that under drought stress, various parts of S. asper leaf anatomy showed some characteristics adapted to water environment. Leaf palisade tissue cells became shorter, increasing from 1-2 layers to 2-3 layers; sponge cells were arranged in neat and compact long column shape, and the upper and down epidermis were thickened. The upper and down epidermis produced more trichomes to resist stress. After rehydration, leaf porosity increased and trichomes had a corresponding reduction. The principal component analysis showed that the stratum corneum thickness, leaf thickness and palisade were available to describe the impact of stress and rehydration on different ages of S. asper leaf anatomy. Under drought stress, S. asper leaf stratum corneum thickness and leaf thickness increased and leaves returned to normal after rehydration. Middle and top leaves were better than basal leaves in response to drought stress sensitivity. 展开更多
关键词 Streblus asper leaves Anatomical structure Drought resistance STRESS
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Contemporary and Historic Population Structure of Abies spectabilis at Treeline in Barun Valley,Eastern Nepal Himalaya 被引量:11
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作者 Parveen Kumar CHHETRI David M.CAIRNS 《Journal of Mountain Science》 SCIE CSCD 2015年第3期558-570,共13页
Treeline ecotone dynamics of Abies spectabilis (D. Don) Mirb. in the Barun valley, Makalu Barun National Park, eastern Nepal Himalaya were studied by establishing seven plots (20 m x variable length) from the fore... Treeline ecotone dynamics of Abies spectabilis (D. Don) Mirb. in the Barun valley, Makalu Barun National Park, eastern Nepal Himalaya were studied by establishing seven plots (20 m x variable length) from the foresfline to the tree species limit: three plots on the south- and north-facing slopes each (S1-S3, N1-N3), and one plot on the east- facing slope (E) in the relatively undisturbed forests. A dendroecological method was used to study treeline advance rate and recruitment pattern. In all the plots, most trees established in the early 20th century, and establishment in the second half of the 20th century was confined to the foresfline area. Treeline position has not advanced substantially in the Barun valley, with 0nly 22 m average elevational shift in the last 13o years, and with average current shifting rate of 14 cm/yr. Moreover, no significant relationship was found between tree age and elevation on the south-, north-, and east-facing slopes. The number of seedlings and saplings in near the treeline area was negligible compared to that near the foresfline area. Therefore, A. spectabilis treeline response to the temperature change was slow, despite the increasing temperature trend in the region. Beside the temperature change, factors such as high inter-annual variability in temperature, dense shrub cover, and local topography also play an important role in treeline advance and controlling recruitment pattern above the treeline. 展开更多
关键词 Climate change Treeline ecotone Treeline advance Recruitment pattern
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XML-based Framework of Parametric Design for Typical Parts
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作者 周炳海 吴斌 陶俐言 《Journal of Donghua University(English Edition)》 EI CAS 2006年第2期34-38,共5页
Parametric design of typical parts holds a very important position during process of product designs. In order to develop a parametric design system of typical parts compatible with heterogeneous CAD systems, this pap... Parametric design of typical parts holds a very important position during process of product designs. In order to develop a parametric design system of typical parts compatible with heterogeneous CAD systems, this paper presents a framework of a network-oriented design system of typical parts, enabled by eXtensible Markup Language (XML), capable of providing parametric design. Firstly, an overview of the framework is presented. In order to map the part feature hierarchy tree of 3D model into an XML tree, an XML-based part template is introduced. The methods of XML-based parametric design and parametric design navigation are described. Finally, an application example of prototype system under the Pro/Engineer platform is given. The application indicates that the proposed framework is valid for parametric design of typical parts/components in heterogeneous CAD systems. 展开更多
关键词 XML CAD data Typical parts Parametric design Structure tree.
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Visualizing Data Tree-Table Based on the Database
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作者 孙广义 侯运炳 +1 位作者 李朝义 张海波 《Journal of China University of Mining and Technology》 2001年第1期56-59,共4页
The data tree table is a type of data structure consisting of data tree and table, which has a wide field of applications. The visual and dynamic growing algorithm of data tree table and its software method are presen... The data tree table is a type of data structure consisting of data tree and table, which has a wide field of applications. The visual and dynamic growing algorithm of data tree table and its software method are presented based on the theory of the data structure and visual technology of software. The method of the expression and management of data tree table with relational mode are explored. 展开更多
关键词 data tree table VISUALIZATION ALGORITHM
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Fatigue Strength Evaluation of Resin-Injected Bolted Connections Using Statistical Analysis 被引量:1
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作者 Jose Antonio Fonseca de Oliveira Correia Bruno Alexandre Silva Pedrosa +6 位作者 Patricia Cordeiro Raposo Abilio Manuel Pinho De Jesus Helena Maria dos Santos Gervisio Grzegorz Stanislaw Lesiukc Carlos Alberto da Silva Rebelo Rui Artur Bartolo Calcada Luis Alberto Proenca Simoes da Silva 《Engineering》 SCIE EI 2017年第6期795-805,共11页
Different strategies can be used to perform reparations and reinforcements of ancient bolted and riveted metallic bridges. As the riveting process is not currently a common practice, it requires proper equipment and s... Different strategies can be used to perform reparations and reinforcements of ancient bolted and riveted metallic bridges. As the riveting process is not currently a common practice, it requires proper equipment and skilled workers. Another solution is the use of welding. However, the weldability of old steels is poor. Bolts are very attractive alternative solutions, and are most commonly used to repair old metallic bridges. Fitted bolts are expensive solutions; the alternative is the use of resin-injected bolts. The behavior of bolted joints with preloaded resin-injected bolts has been studied using quasi-static and creep tests; however, few studies on the slip and fatigue behavior of these joints can be found in the literature. This paper presents an overview of a few experimental programs that were carried out by several authors aiming at evaluating the fatigue behavior of single and double shear resin-injected bolted connections. A comparison between the experimental data of joints with preloaded standard bolts and preloaded resin- injected bolts shows a fatigue strength reduction in the latter. Since Eurocode 3 (EC3) suggests the same fatigue strength curve for joints made of resin-injected bolts and standard bolts, this may raise some con- cerns. Furthermore, research on the feasibility of using both bonded and bolted connections is shown. This last study was performed with high-strength low-alloy structural steel plates and an acrylic struc- tural adhesive for metal bonding. For both case studies, a statistical analysis is performed on fatigue experimental data using linearized boundaries and the Castillo and Fernandez-Canteli model. Fatigue design curves are proposed and compared with the design suggestions of several European and North American standards, 展开更多
关键词 FATIGUE CONNECTIONS Structural reinforcements Structural adhesives S-N curves Resin-injected bolts
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Regeneration ecology and population status of a critically endangered and endemic tree species (Ilex khasiana Purk.) in north-eastern India 被引量:2
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作者 Upadhaya Krishna Barik Saroj Kanta +2 位作者 Adhikari Dibyendu Baishya Ratul Lakadong Nigyal John 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第3期223-228,共6页
Detailed studies on population structure and regeneration ecology ofllex khasiana were carried out at five representative natural populations i.e. Mylliem (Population - I), Upper Shillong (Population - II), Shillo... Detailed studies on population structure and regeneration ecology ofllex khasiana were carried out at five representative natural populations i.e. Mylliem (Population - I), Upper Shillong (Population - II), Shillong Peak (Population -III), Laitkor (Population - IV) and Nongpiyur (Population - V) to probe into the responsible affecting factors for its population structure and regeneration ability in these populations. Experimental observation under three controlled light conditions (full sunlight (100%), intermediate sunlight (50%) and low sunlight (30%)) showed that the growth status and survival rates of seedlings under intermediate and low light were better than those under the high light condition. The density-diameter distribution in population of adult trees (〉Scm dbh) exhibited a typical character of a regenerating population. A higher seedling mortality rate in natural populations of I. khasiana was most probably due to increase in light intensity following vegetation destruction and other anthropogenic disturbances that cause opening of forest canopy. The findings of the present study would be of immense value in formulating appropriate conservation measures for the species. 展开更多
关键词 Ilex khasiana endangered species population status REGENERATION north-eastern India
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Estimation of the Volume of Coarse Woody Debris in Eucalyptus Forest using LiDAR Derived Forest Structure Variables 被引量:1
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作者 Naoko Miura Susumu Goto Simon Jones 《Journal of Environmental Science and Engineering(B)》 2013年第8期501-506,共6页
CWD (coarse woody debris) plays an important role in nutrient cycling, habitat for species and more recently carbon accounting in forest ecosystems. LiDAR (light detection and ranging) technology has demonstrated ... CWD (coarse woody debris) plays an important role in nutrient cycling, habitat for species and more recently carbon accounting in forest ecosystems. LiDAR (light detection and ranging) technology has demonstrated utility in capturing forest structure information. This paper proposes an indirect method of assessing downed CWD using LiDAR derived forest structure variables. Fieldwork was conducted to measure CWD volume in an Eucalyptus forest in Tasmania. A GLM (generalized linear model) to statistically estimate CWD volume in the Eucalyptus forest was developed using a LiDAR derived FCS (forest characterisation scheme): the openings above the ground, low and medium vegetation, canopy cover, presence of understorey and mid-storey vegetation and high trees, and the vertical canopy density of high trees. Five structural variables were selected for the best model based on AIC (Akaike's Information Criterion) by stepwise selection. The applicability of the model was then compared to the outcome of model using field derived variables such as diameter at breast height of trees. The results show that the model using LiDAR derived variables better estimated the amount of CWD. It is concluded that LiDAR derived forest structural variables has the potential to predict the amount of downed CWD in Eucalyptus forest. 展开更多
关键词 CWD (Coarse woody debris) LiDAR (light detection and ranging) FOREST generalized liner model.
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Forest structure of a maple old-growth stand: a case study on the Apennines mountains(Southern Italy) 被引量:2
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作者 Pasquale A.MARZILIANO Vittoria COLETTA +3 位作者 Angelo SCUDERI Clemente SCALISE Giuliano MENGUZZATO Fabio LOMBARDI 《Journal of Mountain Science》 SCIE CSCD 2017年第7期1329-1340,共12页
In Europe, very small forest areas can be considered to be old-growth, and they are mainly located in Eastern Europe. The typical structures of old growth forests infrequently occur in Mediterranean mountainous enviro... In Europe, very small forest areas can be considered to be old-growth, and they are mainly located in Eastern Europe. The typical structures of old growth forests infrequently occur in Mediterranean mountainous environments, since they have been affected by human activities for centuries. This study focused on a remote and almost pure Italian maple stand located in southern Italy, which has not been managed for long time due to its inaccessibility. The effects of natural evolution on the forest stand were evaluated through the analysis of the spatial and chronological structure and the regeneration patterns, then estimating the amounts and quality of deadwood occurrence. Across the whole stand, all the trees with DBH (diameter at breast height) larger than 50 cm (LLT, large living trees) were measured (DBH and height) and age was also determined through a dendrochronological approach. The diameters observed ranged between 50 and 145 cm with ages of 12o to ~5o years. The Latham index calculated for trees within the sample plot highlighted a multilayered canopy with a dominant layer of largeliving trees (age 〉 120 years). The size-class distribution of stems had a reverse-J shape, and basal area was 52 m2 ha-1. Deadwood was exclusively constituted by standing dead trees and CWD and its volume was on average 31 m3 ha-1. Pure Italian maple forests are generally rare in Europe, and it was unexpected to find a forest stand characterized by a so complex structure with old growth attributes. The study of complex forest stand, even if small, could give precious information on the forest evolution, clarifying also diverse auto-ecological traits of tree species that usually are not common in our forests. 展开更多
关键词 Mediterranean mountainous ecosystems Natural evolution Stand characteristics DEADWOOD Unmanaged forests
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Tree-Shaped Timber Structural System
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作者 Decio Gongalves Francisco Antonio Rocco Lahr +2 位作者 Carlito Calil Junior Mauro Augusto Demarzo Andre Luis Christoforo 《Journal of Civil Engineering and Architecture》 2013年第7期796-804,共9页
This paper lbcuses on the main characteristics of a tree-shaped timber structural system or simply tree-shaped. One of them is the complexity of its steel connections, responsible for the joint of bar elements, compou... This paper lbcuses on the main characteristics of a tree-shaped timber structural system or simply tree-shaped. One of them is the complexity of its steel connections, responsible for the joint of bar elements, compounding a complex structural system, which requires the application of the CYPECAD software version 2007 to solve the calculations problems. Its efficiency was confirmed by a variety of laboratory tests carried out with the whole structure. The tree-shaped is a timber structure that can be used in a large number of destinations, including residences, malls, sheds, hangars, etc.. Originally, it was conceived based on the well-known masterpiece "Sagrada Familia", whose author was Architect Antoni Gaudi I Cornet (1852-1926) in Barcelona/Spain. It was designed at the end of 19th century and its construction is still not finished. Gaudi inverted the logical order of the gothic concepts, i.e., light weights below and heavy weights above. Based on this concept, he always had in mind the figure of a tree in nature. The tree-shaped follows the same idea, using timber pieces connected by steel plates. Theoretical and numerical analyses have shown its efficiency and lightness for use in timber structures. 展开更多
关键词 Tree-shaped timber structure system constructive rationality modulated system timber dowels wood.
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Stable Solution of Nonlinear Age-structured Forest Evolution System
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作者 WANGDing-jiang ZHAOTing-fang 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第3期309-313,共5页
This paper studies the dynamical behavior of a class of total area dependent nonlinear age-structured forest evolution model. We give the problem of equal value for the forest system, and discuss the stable solution o... This paper studies the dynamical behavior of a class of total area dependent nonlinear age-structured forest evolution model. We give the problem of equal value for the forest system, and discuss the stable solution of system. We obtained the necessary and sufficient conditions for there exists the stable solution. 展开更多
关键词 NONLINEAR age-structured forest model stable solution
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An efficient embedding tree matching algorithm based on metaphoric dependency syntax tree
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作者 冯少荣 肖文俊 《Journal of Central South University》 SCIE EI CAS 2009年第2期275-279,共5页
To find out all dependency relationships in which metaphors probably exist between syntax constituents in a given sentence,a dependency tree matching algorithm oriented to Chinese metaphor processing is proposed based... To find out all dependency relationships in which metaphors probably exist between syntax constituents in a given sentence,a dependency tree matching algorithm oriented to Chinese metaphor processing is proposed based on a research of unordered tree inclusion matching.In this algorithm,the pattern library is composed of formalization dependency syntax trees that are derived from large-scale metaphor sentences.These kinds of metaphor sentences are saved in the pattern library in advance.The main process of this algorithm is up-down searching and bottom-up backtracking revising.The algorithm discovers potential metaphoric structures in Chinese sentences from metaphoric dependency pattern library.Finally,the feasibility and efficiency of the new matching algorithm are further testified by the results of a series of experiments on dependency pattern library.Hence,accurate dependency relationships can be achieved through this algorithm. 展开更多
关键词 pattern recognition tree matching algorithm dependency tree rule matching metaphor information processing
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Optimization of Synthesis of Spherical Lignosulphonate Resin and Its Structure Characterization 被引量:3
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作者 范娟 詹怀宇 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第3期407-410,共4页
Calcium lignosulphonate was used to synthesize a spherical lignosulphonate resin in a cheap and non-toxic disperse medium by reversed phase suspension polymerization. The process conditions were optimized by orthog... Calcium lignosulphonate was used to synthesize a spherical lignosulphonate resin in a cheap and non-toxic disperse medium by reversed phase suspension polymerization. The process conditions were optimized by orthogonal experiments. Under .the optxmal conditxons (T=95 ℃, CHCl= 3 mol·L^-1, mHCHO: mCLS=7%, WCLS=50%), globulation took about 20 min and the product was featured with excellent spherical shape, narrow particle size range, 61.20% of water retention capacity, 0.83 mmol·ml^- 1 of total volume exchange capacity and 3.46 mmol·g^- 1 of total exchange capacity. The results of Scanning Electron Micrograph and Scanning Probe Micrograph indicate that spherical lignosulphonate resin has a rugged surface with porous microstructure in the gel skeleton. The average pore size of dry samples was determined to be 10.46 nm. by the BET method. 展开更多
关键词 sphencal lignosulphonate resin process optimization structure characterization
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