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The Effect of Na_(2)O/B_(2)O_(3)Composition Ratio on the Structure and Properties of Cu^(+)Doped Luminescent Glass
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作者 LI Bohan FENG Jinyang +3 位作者 FENG Xiaoping ZHAO Xiujian WU Donghua MA Xiao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1379-1390,共12页
Cu^(+)-doped alkali borosilicate glasses with different Na_(2)O contents were prepared by the melting method,and the effects of different R values(R=Na_(2)O/B_(2)O_(3))on the structure,ion presence state and luminesce... Cu^(+)-doped alkali borosilicate glasses with different Na_(2)O contents were prepared by the melting method,and the effects of different R values(R=Na_(2)O/B_(2)O_(3))on the structure,ion presence state and luminescence properties of Cu^(+)-doped alkali borosilicate glasses were investigated.The analysis by FT-IR and Raman spectroscopy shows that,with the increase of R value of the glass,the[BO_(3)]in the structure of Cu^(+)-doped alkali borosilicate glass transforms into[BO_(4)]and the number of non-bridging oxygen in the glass network appears to be slightly increased.The absorption spectra and EPR analysis reveal that the Cu^(+)content in the glass gradually decreases and the Cu^(2+)content gradually increases as the R value of the glass increases.XPS and PL tests further indicate that the transformation of the octahedral coordination structure of Cu^(+)to the octahedral coordination structure of Cu^(2+)and the cubic coordination structure of Cu^(+)occurs in the glass as the R value of the glass increases.This transformation can effectively reduce the concentration quenching phenomenon of Cu^(+)and improve the fluorescence luminescence intensity of the glass samples.Meanwhile,the samples were found to have luminescence tunability as well as good thermal stability. 展开更多
关键词 R value glass structure Cu ion valence LUMINESCENCE
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Multi-scale pore fractal characteristics of differently ranked coal and its impact on gas adsorption 被引量:3
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作者 Zhongbei Li Ting Ren +4 位作者 Xiangchun Li Ming Qiao Xiaohan Yang Lihai Tan Baisheng Nie 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第4期389-401,共13页
Well-developed pores and cracks in coal reservoirs are the main venues for gas storage and migration.To investigate the multi-scale pore fractal characteristics,six coal samples of different rankings were studied usin... Well-developed pores and cracks in coal reservoirs are the main venues for gas storage and migration.To investigate the multi-scale pore fractal characteristics,six coal samples of different rankings were studied using high-pressure mercury injection(HPMI),low-pressure nitrogen adsorption(LPGA-N2),and scanning electron microscopy(SEM)test methods.Based on the Frankel,Halsey and Hill(FHH)fractal theory,the Menger sponge model,Pores and Cracks Analysis System(PCAS),pore volume complexity(D_(v)),coal surface irregularity(Ds)and pore distribution heterogeneity(D_(p))were studied and evaluated,respectively.The effect of three fractal dimensions on the gas adsorption ability was also analyzed with high-pressure isothermal gas adsorption experiments.Results show that pore structures within these coal samples have obvious fractal characteristics.A noticeable segmentation effect appears in the Dv1and Dv2fitting process,with the boundary size ranging from 36.00 to 182.95 nm,which helps differentiate diffusion pores and seepage fractures.The D values show an asymmetric U-shaped trend as the coal metamorphism increases,demonstrating that coalification greatly affects the pore fractal dimensions.The three fractal dimensions can characterize the difference in coal microstructure and reflect their influence on gas adsorption ability.Langmuir volume(V_(L))has an evident and positive correlation with Dsvalues,whereas Langmuir pressure(P_(L))is mainly affected by the combined action of Dvand Dp.This study will provide valuable knowledge for the appraisal of coal seam gas reservoirs of differently ranked coals. 展开更多
关键词 Multi-scale pore structure Fractal theory Fractal characteristics Differently ranked coal Coalbed gas adsorption
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Variations of population structure and important value of the main edificators along the elevation gradient on the northern slope of Changbai Mountain 被引量:1
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作者 姜萍 叶吉 +1 位作者 郝占庆 邓红兵 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期117-121,共5页
From 700 m to 1900 m on the northern slope of Changbai Mountain, 13 plots with an interval of 100 m in elevation were investigated to study the variations of population structure and important value of the main edific... From 700 m to 1900 m on the northern slope of Changbai Mountain, 13 plots with an interval of 100 m in elevation were investigated to study the variations of population structure and important value of the main edificators along the elevation gradient. In their core distribution areas, most of the edificators had healthy population structure and could regenerate smoothly except Larix olgensis, but important value of Larix olgensis had no obvious variations with elevation changes, which showed that Larix olgensis had its own particularity and strong adaptability. At high elevation above 1800 m, Betula ermanii was the only species that could form a mono-dominant community. Important values of Pinus koraiensis and Acer mono had similar changing trends, and they had the similar ecological adaptabilities. 展开更多
关键词 Edificator POPULATION Important value structure Elevation gradient Changbai Mountain
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PHYSICAL VALUE MAPPING ALGORITHM OF MESH IN FINE CAE ANALYSIS OF AUTOMOBILE BODY STRUCTURE 被引量:2
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作者 Hu Ping Gong Kejia Bao Yidong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第3期338-341,共4页
A physical value mapping (PVM) algorithm based on finite element mesh from the stamped part in stamping process to the product is presented, In order to improve the efficiency of the PVM algorithm, a search way from... A physical value mapping (PVM) algorithm based on finite element mesh from the stamped part in stamping process to the product is presented, In order to improve the efficiency of the PVM algorithm, a search way from the mesh of the product to the mesh of the stamped part will be adopted. At the same time, the search process is divided into two steps: entire search (ES) and local search (LS), which improve the searching efficiency. The searching area is enlarged to avoid missing projection elements in ES process. An arc-length method is introduced in LS process. The validity is confirmed by the results of the complex industry-forming product. 展开更多
关键词 Fine CAE analysis of auto body structure Finite element mesh Arc method Physical value mapping
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X-ray absorption near-edge structure study on the configuration of Cu2+/histidine complexes at different pH values
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作者 于梅娟 王宇 徐伟 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第4期474-478,共5页
The local configurations around metal ions in metalloproteins are of great significance for understanding their biolog- ical functions. Cu2+/histidine (His) is a typical complex existing in many metalloproteins and... The local configurations around metal ions in metalloproteins are of great significance for understanding their biolog- ical functions. Cu2+/histidine (His) is a typical complex existing in many metalloproteins and plays an important role in lots of physiological functions. The three-dimensional (3D) structural configurations of Cu2+/His complexes at different pH values (2.5, 6.5, and 8.5) are quantitatively determined by x-ray absorption near-edge structure (XANES). Generally Cu2+/His complex keeps an octahedral configuration consisting of oxygen atoms from water molecules and oxygen or nitrogen atoms from histidine molecules coordinated around Cu2+. It is proved in this work that the oxygen atoms from water molecules, when increasing the pH value from acid to basic value, are gradually substituted by the Ocarboxy1, Nam, and Nim from hisitidine molecules. Furthermore, the symmetries of Cu2+/His complexes at pH 6.5 and pH 8.5 are found to be lower than at pH 2.5. 展开更多
关键词 x-ray absorption near-edge structure Cu2+/His pH values CONFIGURATION
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Numerical Computation of Structured Singular Values for Companion Matrices
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作者 Mutti-Ur Rehman Shabana Tabassum 《Journal of Applied Mathematics and Physics》 2017年第5期1057-1072,共16页
In this article, the computation of μ-values known as Structured Singular Values SSV for the companion matrices is presented. The comparison of lower bounds with the well-known MATLAB routine mussv is investigated. T... In this article, the computation of μ-values known as Structured Singular Values SSV for the companion matrices is presented. The comparison of lower bounds with the well-known MATLAB routine mussv is investigated. The Structured Singular Values provides important tools to analyze the stability and instability analysis of closed loop time invariant systems in the linear control theory as well as in structured eigenvalue perturbation theory. 展开更多
关键词 structureD SINGULAR value Block DIAGONAL MATRICES Spectral RADIUS Low-rank Approximation
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Creative Teaching + Creative Class = Creative Products + Additional Value—A Case Study of Course Reform of Three-dimension Structure
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作者 SUN Jingsong 《Journal of Landscape Research》 2014年第5期49-50,共2页
The teaching model of "creative Teaching + creative class = creative products + additional value" was proposed, so as to cultivate students' design creativity and practical ability by changing teaching c... The teaching model of "creative Teaching + creative class = creative products + additional value" was proposed, so as to cultivate students' design creativity and practical ability by changing teaching concepts and curriculum of Three-dimension Structure, and using new materials for spatial creativity training. This paper acclaims that only if the traditional teaching concepts of Three-dimension Structrue are abandoned, students' specialty fully used, the teaching effect will be improved effectively. 展开更多
关键词 Three-dimension structure Creative teaching Additional value
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Community Structure and Value Evaluation of Local Brassicaceae Potherbs in Shiyan City
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作者 Yaowen XU Shuiyuan CHENG +3 位作者 Yongjun FEI Zurong CAO Yingjie LI Longsheng HU 《Agricultural Biotechnology》 CAS 2021年第5期30-36,共7页
[Objectives]This study was conducted to evaluate the value of local Brassicaceae potherb resources in Shiyan City.[Methods]Seven species of local Brassicaceae edible plants resources in Shiyan City,including Cardamine... [Objectives]This study was conducted to evaluate the value of local Brassicaceae potherb resources in Shiyan City.[Methods]Seven species of local Brassicaceae edible plants resources in Shiyan City,including Cardamine hirsuta L.,Cardamine flexuosa,Cardamine impatiens L.,Capsella bursa-pastoris(Linn.),Orychophragmus violaceus(L.)O.E.Schulz,Draba nemorosa L.,Rorippa indica(L.)Hiern.,were investigated using sampling method,and their value was evaluated.[Results]①Shiyan City was rich in resources of local Brassicaceae potherbs,mostly of which grew in humid areas.②In the communities of target species,there were 20 species of plants in 19 genera of 15 families in the arbor layer,19 species of plants in 16 genera from 15 families in the shrub layer,and 58 species of plants in 51 genera from 23 families in the herbaceous layer.The tree,shrub and herb species with the highest dominance Populus simonii var.przewalskii,Robinia pseudoacacia and Chrysanthemum indicum.Local Brassicaceae potherbs in Shiyan City have high edible and medicinal value,especially Cardamine,which has strong selenium-rich ability and is worthy of vigorous development.[Conclusions]This study provides scientific basis and reference for the development and utilization of local potherbs of Brassicaceae in this area. 展开更多
关键词 Brassicaceae Wild vegetables CARDAMINE Community structure analysis value evaluation
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The Value Structure and Reconstruction of China's Rural Civilization in the New Era——An Exploration of Rural Revitalization through the Rejuvenation of Rural Civilization
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作者 Wang Zhongwu Xu Qingtong Wu Lingwei 《Contemporary Social Sciences》 2018年第5期118-130,共13页
Rural civilization is a pattern of human civilization that is profoundly linked with values.Rural revitalization means the rejuvenation of rural civilization under new historical circumstances.To that end,it is necess... Rural civilization is a pattern of human civilization that is profoundly linked with values.Rural revitalization means the rejuvenation of rural civilization under new historical circumstances.To that end,it is necessary to adopt a holistically interpreting mode that transcends individual cases,and to look through the wide-angle lens of civilization and grasp rural civilization's development trend of "prosperity-decline-rejuvenation," as well as its constructive route of "traditional construction-modern deconstructionneo-modern reconstruction." This paper analyzes the "three-in-one" value structure concerning rural civilization's being a cultural carrier,its subjective demands,and objective production,to understand and follow the diachronic evolution of the position and function of rural civilization values "from being a subject,through being an object,to being a subject." Based on this,this paper studies the construction of a subjective rural civilization with Chinese characteristics in the new era and explores a possible approach to rural revitalization through the rejuvenation of rural civilization.Accordingly,the basic idea and strategy is to boost the rejuvenation of rural civilization through innovative time-space integration; to establish rural civilization's subjective status and to always prioritize agricultural and rural development; to rediscover and redefine the principles,values and functions of the rural civilization construction in the new era; and to further advance campaigns of rural civilization constructions to integrate the development of urban civilization with that of rural civilization. 展开更多
关键词 rural revitalization rejuvenation of rural civilization value structure reconstruction in the new era
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Robust ranking of multi-criteria alternatives using value functions compatible with holistic preference information
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作者 SLOWINSKI Roman GRECO Salvatore2 +1 位作者 FIGUEIRA José Rui MOUSSEAU Vincent 《重庆邮电大学学报(自然科学版)》 2008年第3期324-334,共11页
We present two recent methods,called UTAGMS and GRIP,from the viewpoint of robust ranking of multi-criteria alternatives.In these methods,the preference information provided by a single or multiple Decision Makers(DMs... We present two recent methods,called UTAGMS and GRIP,from the viewpoint of robust ranking of multi-criteria alternatives.In these methods,the preference information provided by a single or multiple Decision Makers(DMs)is composed of holistic judgements of some selected alternatives,called reference alternatives.The judgements express pairwise comparisons of some reference alternatives(in UTAGMS),and comparisons of selected pairs of reference alternatives from the viewpoint of intensity of preference(in GRIP).Ordinal regression is used to find additive value functions compatible with this preference information.The whole set of compatible value functions is then used in Linear Programming(LP)to calculate a necessary and possible weak preference relations in the set of all alternatives,and in the set of all pairs of alternatives.While the necessary relation is true for all compatible value functions,the possible relation is true for at least one compatible value function.The necessary relation is a partial preorder and the possible relation is a complete and negatively transitive relation.The necessary relations show consequences of the given preference information which are robust because "always true".We illustrate this methodology with an example. 展开更多
关键词 信息处理 选择方案 函数 计算机技术
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Influence of pH Value on Photocatalytic Activity of Bi4Ti3O12 Crystals Obtained by Hydrothermal Method 被引量:1
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作者 林雪 宫宇宁 +2 位作者 张耀丹 闫永胜 关庆丰 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第2期209-213,I0004,共6页
Bi4Ti3O12 (BIT) crystals were controllably synthesized via a facile hydrothermal process without adding any surfactant or template. The morphologies of BIT with nanosphere, nanoplate, nanobelt, and nanosheet can be ... Bi4Ti3O12 (BIT) crystals were controllably synthesized via a facile hydrothermal process without adding any surfactant or template. The morphologies of BIT with nanosphere, nanoplate, nanobelt, and nanosheet can be selectively obtained by adjusting the pH value of the reactant. The formation mechanisms of these distinctive morphologies were then discussed based on the structural analysis of samples obtained at different pH values. BIT sample prepared at pH=1 showed the highest photocatalytic activity under visible light irradiation. The photocatalytic activities difference for the BIT samples synthesized at different pH values was studied based on their shape, size, and the variation of local structure. 展开更多
关键词 PHOTOCATALYSIS BI4TI3O12 pH value Local structure
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STRUCTURE OPTIMIZATION STRATEGY OF NORMALIZED RBF NETWORKS 被引量:1
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作者 祖家奎 赵淳生 戴冠中 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第1期73-78,共6页
Aimed at studying normali zed radial basis function network (NRBFN), this paper introduces the subtractiv e clustering based on a mountain function to construct the initial structure of NR BFN, adopts singular value ... Aimed at studying normali zed radial basis function network (NRBFN), this paper introduces the subtractiv e clustering based on a mountain function to construct the initial structure of NR BFN, adopts singular value decomposition (SVD) to analyze the relationship betwe en neural nodes of the hidden layer and singular values, cumulative contribution ratio, index vector, and optimizes the structure of NRBFN. Finally, simulation and performance comparison show that the algorithm is feasible and effective. 展开更多
关键词 radial basis function n etworks subtractive clustering singular value decomposition structure optimiz ation
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Discussion on Selection of Wood Structure of Ancient Buildings in China
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作者 金东来 权莹 金华 《Journal of Landscape Research》 2012年第5期27-30,共4页
Based on wood structure of ancient buildings in China,the paper considers that Chinese ancient people have selected wood as the architectural material due to its characteristics and some necessity.After the analysis o... Based on wood structure of ancient buildings in China,the paper considers that Chinese ancient people have selected wood as the architectural material due to its characteristics and some necessity.After the analysis of architectural features of traditional settlements,it has found that Chinese ancient people tend to draw on local materials for construction.Then,it further analyzes the adaptability of Chinese wood structure,and the flexibility and complexity of its plane layout.By combining with Chinese's life value,the eternal significance contained in wood structure has been explained based on material and spiritual level.From the perspective of natural selection,technological advancement,spatial advantage,spiritual value and aesthetic need,the paper tries to find causes for wood structure as architectural materials,aiming to objectively treat the effort of Chinese ancient people made in the progress history of human civilization. 展开更多
关键词 WOOD structure DRAWING on local materials MATURE FORM Spatial ADAPTABILITY Life value
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Design of foundation structures of sea-crossing bridges on serviceability limit state
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作者 金伟良 胡琦忠 +2 位作者 帅长斌 于群力 鲁征 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期74-79,共6页
The target reliability indices of the foundation structures of sea-crossing bridges on the serviceability limit state (SLS) are different from those of common bridges due to their different surroundings. Consequentl... The target reliability indices of the foundation structures of sea-crossing bridges on the serviceability limit state (SLS) are different from those of common bridges due to their different surroundings. Consequently, three levels of the target reliability indices, which are 1.5, 2. 0 and 2. 3, respectively, for those structures on the SLS are suggested based on the Joint Committee on Structural Safety (JCSS) model code, and a new method of calibrating factors of live loads, which is based on the contribution ratio of tensile stresses of reinforcing bars produced by various loads to the maximum crack width of concrete, is proposed. Finally, the calibration of the reliability-based factors of the frequent value and the quasi-permanent value of live loads is conducted by the Joint Committee (JC) method through an actual design, and the indices are proved to be reasonable and the new method is proved to be feasible. 展开更多
关键词 sea-crossing bridges target reliability JC (Joint Committee) method frequent value quasi-permanent value foundation structures
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Influence of Traditional Chinese Values on Consumer Behavior:the Case of Mobile in Shanghai 被引量:4
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作者 潘煜 高丽 +1 位作者 陈小燕 Gérard Cliquet 《China Communications》 SCIE CSCD 2011年第3期118-132,共15页
This study investigates how traditional Chinese values influence Chinese consumer behavior directly and indirectly through the impact on people's lifestyles and perceived values.The empirical research is conducted... This study investigates how traditional Chinese values influence Chinese consumer behavior directly and indirectly through the impact on people's lifestyles and perceived values.The empirical research is conducted in the context of the mobile phone market in Shanghai.The study establishes measurement scales of Confucian value,lifestyle,and customer perceived value for Chinese market.Relationships of multiple factors are tested in the structural equation model and their impacts on consumer behavior are elaborated.Findings indicate that Confucian values not only have a direct impact on Chinese consumer behavior but also indirectly influence this behavior through impacting people's lifestyles and perceived values. 展开更多
关键词 measurement and scale development issues structural equation model China Confucian values customer perceived value LIFESTYLE
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The Analysis of Seismic Data Structure and Oil and Gas Prediction 被引量:14
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作者 WangShangxu LinChangrong 《Applied Geophysics》 SCIE CSCD 2004年第2期75-82,共8页
In this paper, a new concept called numerical structure of seismic data is introduced and the difference between numerical structure and numerical value of seismic data is explained. Our study shows that the numerical... In this paper, a new concept called numerical structure of seismic data is introduced and the difference between numerical structure and numerical value of seismic data is explained. Our study shows that the numerical seismic structure is closely related to oil and gas-bearing reservoir, so it is very useful for a geologist or a geophysicist to precisely interpret the oil-bearing layers from the seismic data. This technology can be applied to any exploration or production stage. The new method has been tested on a series of exploratory or development wells and proved to be reliable in China. Hydrocarbon-detection with this new method for 39 exploration wells on 25 structures indi- cates a success ratio of over 80 percent. The new method of hydrocarbon prediction can be applied for: (1) depositional environment of reservoirs with marine fades, delta, or non-marine fades (including fluvial facies, lacustrine fades); (2) sedimentary rocks of reservoirs that are non-marine clastic rocks and carbonate rock; and (3) burial depths range from 300 m to 7000 m, and the minimum thickness of these reservoirs is over 8 m (main frequency is about 50 Hz). 展开更多
关键词 hydrocarbon prediction hydrocarbon oil-bearing stratum seismic data structure data value seismic facies
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Optimization of Land Use Structure Based on Ecological GREEN Equivalent 被引量:7
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作者 LIU Yanfang MING Dongping YANG Jianyu 《Geo-Spatial Information Science》 2002年第4期60-67,共8页
Optimization of land use structure consists of economic and social and ecological optimization.Applying the minds of system engineering and principles of ecology,this paper presents such thoughts:the optimal forest_co... Optimization of land use structure consists of economic and social and ecological optimization.Applying the minds of system engineering and principles of ecology,this paper presents such thoughts:the optimal forest_coverage rate calculated according to the reality of a district is set as main standard of ecological rationality in the district;through considering the value of ecosystem services of the land with GREEN equivalent (mainly cultivated land and grassland)and based on the rule,GREEN equivalent,this paper introduces the area conversion between woodland and cultivated land,also between woodland and grassland;this paper establishes a multi_dimension controlling model of optimization of land use structure.In addition,a multi_objective linear programming model for optimization of land use structure is designed.In the end,this paper tests and verifies this theory of ecological optimization,taking Qionghai city in Hainan Province as an example. 展开更多
关键词 land use structure forest_coverage rate GREEN equivalent value of ecosystem services multi_dimension optimization multi_objective linear programming
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Coverless Information Hiding Based on the Molecular Structure Images of Material 被引量:10
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作者 Yi Cao Zhili Zhou +1 位作者 Xingming Sun Chongzhi Gao 《Computers, Materials & Continua》 SCIE EI 2018年第2期197-207,共11页
The traditional information hiding methods embed the secret information by modifying the carrier,which will inevitably leave traces of modification on the carrier.In this way,it is hard to resist the detection of steg... The traditional information hiding methods embed the secret information by modifying the carrier,which will inevitably leave traces of modification on the carrier.In this way,it is hard to resist the detection of steganalysis algorithm.To address this problem,the concept of coverless information hiding was proposed.Coverless information hiding can effectively resist steganalysis algorithm,since it uses unmodified natural stego-carriers to represent and convey confidential information.However,the state-of-the-arts method has a low hidden capacity,which makes it less appealing.Because the pixel values of different regions of the molecular structure images of material(MSIM)are usually different,this paper proposes a novel coverless information hiding method based on MSIM,which utilizes the average value of sub-image’s pixels to represent the secret information,according to the mapping between pixel value intervals and secret information.In addition,we employ a pseudo-random label sequence that is used to determine the position of sub-images to improve the security of the method.And the histogram of the Bag of words model(BOW)is used to determine the number of subimages in the image that convey secret information.Moreover,to improve the retrieval efficiency,we built a multi-level inverted index structure.Furthermore,the proposed method can also be used for other natural images.Compared with the state-of-the-arts,experimental results and analysis manifest that our method has better performance in anti-steganalysis,security and capacity. 展开更多
关键词 Coverless information hiding molecular structure images of material pixel value inverted index image retrieval bag of words model
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The height-width ratio limited value for rubber bearing isolated structure computed by uniform design method 被引量:7
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作者 王铁英 王焕定 +1 位作者 张永山 刘文光 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第1期36-40,共5页
Rubber isolation is the most mature control technology in practical application, and is widely used by short rigid buildings. However, many high isolation buildings have been built around the world in recent years, wh... Rubber isolation is the most mature control technology in practical application, and is widely used by short rigid buildings. However, many high isolation buildings have been built around the world in recent years, which do not follow the existing criterions and codes. Many researchers began to research the special problems caused by larger height-width ratio isolation structures. The overturning effect of high height-width ratio structures with rubber bearing is firstly studied. Considering the main factors, such as the height-width ratio of structures, type of site, the designed basic acceleration of ground motion and the decouple factor in horizon, computing experiment is defined with the Uniform Design Method, which is also known as designing isolation structure. The forces of the bearing under edge of structures based on the position of the rubber bearing are calculated. The result indicates that the rubber bearings will lose its functionality under very high tension and compressing force of earthquake motion in horizon and vertical, when the height-width ratio is over a certain value. Thus, based on the calculation result of isolation structures defined in the uniform design method, regression analysis is conducted, and also the rubber edge force regression formula are gotten, which has higher correlation and smaller standard deviation. This formula can be used to roughly calculate whether the pull force occurs at the edge of the building. By the edge bearings of isolation structure minimum force formula, the height-width ratio limited value of the isolation structure is deducted when rubber bearing has minimum force of zero. 展开更多
关键词 isolation structures the uniform design method regression analysis height-width ratio limited value
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Effects of selection cutting on the forest structure and species diversity of evergreen broad-leaved forest in northern Fujian, southern China 被引量:2
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作者 Qiu Ren-hui Chen Han Zhuo Li-xin 《Forestry Studies in China》 CAS 2006年第1期16-20,共5页
The short-term effects of selection curing of different intensities on the forest structure and species diversity of evergreen broad-leaved forest in northern Fujian Province were investigated and analyzed. The result... The short-term effects of selection curing of different intensities on the forest structure and species diversity of evergreen broad-leaved forest in northern Fujian Province were investigated and analyzed. The results showed that selection curing of low and medium intensities caused little variation in the forest structure. After curing, the dominant species retained their leading status in the community. However, the community structure changed significantly following selection curing of high and extra-high intensities; the status of the dominant species of the community declined dramatically. Some tree species began to disappear from the sampling plots. Except for extra-high intensity curing, the diversity of tree species did not change significantly for the other three curing intensities. However, the evenness of the stands was very different among the four kinds of curing plots. For low and medium intensity selection cutting, the evenness declined slightly. For extra-high intensity selection curing, the evenness increased to some extent, which might be due to a more even distribution of tree species after curing. CuRing operations resulted in some adverse reactions to development of arborous species diversity of evergreen broad-leaved forest, particularly serious damage to the forest canopy. But the rational selection cuttings, which may benefit the restoration and maintenance of species diversity over a long period and may come about from the variations in environmental factors such as sunlight, temperature and humidity. 展开更多
关键词 selection cutting forest structure cutting intensities importance value species diversity
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