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Galaxy Interactions in Filaments and Sheets:Effects of the Large-scale Structures Versus the Local Density
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作者 Apashanka Das Biswajit Pandey Suman Sarkar 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第2期197-204,共8页
Major interactions are known to trigger star formation in galaxies and alter their color.We study the major interactions in filaments and sheets using SDSS data to understand the influence of large-scale environments ... Major interactions are known to trigger star formation in galaxies and alter their color.We study the major interactions in filaments and sheets using SDSS data to understand the influence of large-scale environments on galaxy interactions.We identify the galaxies in filaments and sheets using the local dimension and also find the major pairs residing in these environments.The star formation rate(SFR) and color of the interacting galaxies as a function of pair separation are separately analyzed in filaments and sheets.The analysis is repeated for three volume limited samples covering different magnitude ranges.The major pairs residing in the filaments show a significantly higher SFR and bluer color than those residing in the sheets up to the projected pair separation of~50 kpc.We observe a complete reversal of this behavior for both the SFR and color of the galaxy pairs having a projected separation larger than 50 kpc.Some earlier studies report that the galaxy pairs align with the filament axis.Such alignment inside filaments indicates anisotropic accretion that may cause these differences.We do not observe these trends in the brighter galaxy samples.The pairs in filaments and sheets from the brighter galaxy samples trace relatively denser regions in these environments.The absence of these trends in the brighter samples may be explained by the dominant effect of the local density over the effects of the large-scale environment. 展开更多
关键词 methods statistical-methods data analysis-galaxies evolution-galaxies interactions-(cosmology:)large-scale structure of universe
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Neutrino Mass Constraints from Reconstructing the Large-scale Structure:Systematic Uncertainty
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作者 Chok Lap Chung Derek Inman +4 位作者 Xin Wang Erhao Shang Zi Zhuang Fucheng Yuan Ue-Li Pen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第6期65-73,共9页
We examine the possibility of applying the baryonic acoustic oscillation reconstruction method to improve the neutrino massΣm_νconstraint.Thanks to the Gaussianization of the process,we demonstrate that the reconstr... We examine the possibility of applying the baryonic acoustic oscillation reconstruction method to improve the neutrino massΣm_νconstraint.Thanks to the Gaussianization of the process,we demonstrate that the reconstruction algorithm could improve the measurement accuracy by roughly a factor of two.On the other hand,the reconstruction process itself becomes a source of systematic error.While the algorithm is supposed to produce the displacement field from a density distribution,various approximations cause the reconstructed output to deviate on intermediate scales.Nevertheless,it is still possible to benefit from this Gaussianized field,given that we can carefully calibrate the“transfer function”between the reconstruction output and theoretical displacement divergence from simulations.The limitation of this approach is then set by the numerical stability of this transfer function.With an ensemble of simulations,we show that such systematic error could become comparable to statistical uncertainties for a DESI-like survey and be safely neglected for other less ambitious surveys. 展开更多
关键词 (cosmology:)large-scale structure of universe cosmology:observations NEUTRINOS
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Quantifying forest structural diversity based on large-scale inventory data:a new approach to support biodiversity monitoring 被引量:3
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作者 Felix Storch Carsten F.Dormann Jurgen Bauhus 《Forest Ecosystems》 SCIE CSCD 2018年第4期472-485,共14页
Background: The importance of structurally diverse forests for the conservation of biodiversity and provision of a wide range of ecosystem services has been widely recognised. However, tools to quantify structural div... Background: The importance of structurally diverse forests for the conservation of biodiversity and provision of a wide range of ecosystem services has been widely recognised. However, tools to quantify structural diversity of forests in an objective and quantitative way across many forest types and sites are still needed, for example to support biodiversity monitoring. The existing approaches to quantify forest structural diversity are based on small geographical regions or single forest types, typically using only small data sets.Results: Here we developed an index of structural diversity based on National Forest Inventory(NFI) data of BadenWurttemberg, Germany, a state with 1.3 million ha of diverse forest types in different ownerships. Based on a literature review, 11 aspects of structural diversity were identified a priori as crucially important to describe structural diversity. An initial comprehensive list of 52 variables derived from National Forest Inventory(NFI) data related to structural diversity was reduced by applying five selection criteria to arrive at one variable for each aspect of structural diversity. These variables comprise 1) quadratic mean diameter at breast height(DBH), 2) standard deviation of DBH, 3) standard deviation of stand height, 4) number of decay classes, 5) bark-diversity index, 6) trees with DBH ≥ 40 cm, 7) diversity of flowering and fructification, 8) average mean diameter of downed deadwood, 9) mean DBH of standing deadwood, 10) tree species richness and 11) tree species richness in the regeneration layer. These variables were combined into a simple,additive index to quantify the level of structural diversity, which assumes values between 0 and 1. We applied this index in an exemplary way to broad forest categories and ownerships to assess its feasibility to analyse structural diversity in large-scale forest inventories.Conclusions: The forest structure index presented here can be derived in a similar way from standard inventory variables for most other large-scale forest inventories to provide important information about biodiversity relevant forest conditions and thus provide an evidence-base for forest management and planning as well as reporting. 展开更多
关键词 Stand structure structural diversity structural diversity index large-scale forest inventory Angle count sampling
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Development Trend of NC Machining Accuracy Control Technology for Aeronautical Structural Parts
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作者 Qingchun Xiong Qinghua Zhou 《World Journal of Engineering and Technology》 2020年第3期266-279,共14页
High-performance five-axis computer numerical control machine tools are widely used in the processing of Aeronautical Structural parts. With the increase of service life, the precision of CNC machine tools equipped by... High-performance five-axis computer numerical control machine tools are widely used in the processing of Aeronautical Structural parts. With the increase of service life, the precision of CNC machine tools equipped by aeronautical manufacturing enterprises is declining day by day, while the new generation of aircraft structural parts <span style="font-family:Verdana;">are</span><span style="font-family:Verdana;"> developing towards integration, large-scale, complexity, thin-walled and lightweight. It is very easy to produce dimension overshoot and surface quality defects due to unstable processing technology. The machining accuracy of aircraft structural parts is also affected by complex factors such as cutting load, cutting stability, tool error, workpiece deformation, fixture deformation, etc. Because of the complexity of structure and characteristics of Aeronautical Structural parts, the consistency and stability of cutting process are poor. It is easy to cause machining accuracy problems due to tool wear, breakage and cutting chatter. Relevant scholars have carried out a lot of basic research on NC machining accuracy control and achieved fruitful results, but the research on NC machining accuracy control of Aeronautical structural parts is still less. This paper elaborates from three aspects: error modeling method of NC machine tools, error compensation method, prediction and control of machining accuracy, and combines the characteristics of Aeronautical Structural parts, the development trend and demand of NC machining accuracy control technology are put forward.</span> 展开更多
关键词 Aeronautical structural parts Machining Accuracy Error Compensation Machining Accuracy Control
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Study on the crust-mantle structure in the central and southern parts of Shanxi 被引量:3
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作者 祝治平 张建狮 +7 位作者 张成科 赵金仁 刘明清 唐周琼 盖玉杰 任青芳 聂文英 杨清 《Acta Seismologica Sinica(English Edition)》 CSCD 1999年第1期46-54,共9页
Another comparative interpretation was conducted with respect to the data from 5 DSS profiles in the central and southern parts of Shanxi, leading to the conclusion that in Linxian, Linfen and Xingtai earthquake regio... Another comparative interpretation was conducted with respect to the data from 5 DSS profiles in the central and southern parts of Shanxi, leading to the conclusion that in Linxian, Linfen and Xingtai earthquake regions, through which the five profiles pass, there exist anomalous crust mantle structure and abyssal crustal faults extending to Moho, all being regarded as the deep indications for earthquake occurrence. 展开更多
关键词 the central and southern parts of Shanxi deep seismic sounding crust mantle structure and deep tectonics
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Alignment between galaxies and large-scale structure 被引量:1
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作者 A. Faltenbacher Cheng Li +3 位作者 Simon D. M. White Yi-Peng Jing Shu-De Mao Jie Wang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2009年第1期41-58,共18页
Based on the Sloan Digital Sky Survey DR6 (SDSS) and the 'Millennium Simulation (MS), we investigate the alignment between galaxies and large-scale structure. For this purpose, we develop two new statistical tool... Based on the Sloan Digital Sky Survey DR6 (SDSS) and the 'Millennium Simulation (MS), we investigate the alignment between galaxies and large-scale structure. For this purpose, we develop two new statistical tools, namely the alignment correlation function and the cos(20)-statistic. The former is a two-dimensional extension of the traditional two-point correlation function and the latter is related to the ellipticity correlation function used for cosmic shear measurements. Both are based on the cross correlation between a sample of galaxies with orientations and a reference sample which represents the large-scale structure. We apply the new statistics to the SDSS galaxy catalog. The alignment correlation function reveals an overabundance of reference galaxies along the major axes of red, luminous (L 〉 ~L*) galaxies out to projected separations of 60 h-lMpc. The signal increases with central galaxy luminosity. No alignment signal is detected for blue galaxies. The cos(2θ)-statistic yields very similar results. Starting from a MS semi-analytic galaxy catalog, we assign an orientation to each red, luminous and central galaxy, based on that of the central region of the host halo (with size similar to that of the stellar galaxy). As an alternative, we use the orientation of the host halo itself. We find a mean projected misalignment between a halo and its central region of -25°. The misalignment decreases slightly with increasing luminosity of the central galaxy. Using the orientations and luminosities of the semi-analytic galaxies, we repeat our alignment analysis on mock surveys of the MS. Agreement with the SDSS results is good if the central orientations are used. Predictions using the halo orientations as proxies for cen- tral galaxy orientations overestimate the observed alignment by more than a factor of 2. Finally, the large volume of the MS allows us to generate a two-dimensional map of the alignment correlation function, which shows the reference galaxy distribution to be flat- tened parallel to the orientations of red luminous galaxies with axis ratios of -0.5 and ,-0.75 for halo and central orientations, respectively. These ratios are almost independent of scale out to 60 h^-1 Mpc. 展开更多
关键词 dark matter halos clustering-galaxies large-scale structure of Universe- cosmology theory -dark matter
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A Summary of the Large-Scale Access Convergence Network Structure
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作者 LAN Julong ZHANG Xiaohui +5 位作者 SHEN Juan HU Yuxiang WANG Xiang MAO Zhenshan WANG Lingqiang LIANG Dong 《China Communications》 SCIE CSCD 2016年第S1期1-5,共5页
Under the requirement of everything over IP, network service shows the following characteristics:(1) network service increases its richness;(2) broadband streaming media becomes the mainstream. To achieve unified mult... Under the requirement of everything over IP, network service shows the following characteristics:(1) network service increases its richness;(2) broadband streaming media becomes the mainstream. To achieve unified multi-service bearing in the IP network, the largescale access convergence network architecture is proposed. This flat access convergence structure with ultra-small hops, which shortens the service transmission path, reduces the complexity of the edge of the network, and achieves IP strong waist model with the integration of computation, storage and transmission. The key technologies are also introduced in this paper, including endto-end performance guarantee for real time interactive services, fog storing mechanism, and built-in safety transmission with integration of aggregation and control. 展开更多
关键词 network architecture large-scale ACCESS CONVERGENCE flat structure ultra-small HOPS
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Dynamics of Secondary Large-Scale Structures in ETG Turbulence Simulations
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作者 李继全 Y.KISHIMOTO +2 位作者 董家齐 N.MIYATO T.MATSUMOTO 《Plasma Science and Technology》 SCIE EI CAS CSCD 2006年第1期110-113,共4页
The dynamics of secondary large-scale structures in electron-temperature-gradient (ETG) turbulence is investigated based on gyrofluid simulations in sheared slab geometry. It is found that structural bifurcation to ... The dynamics of secondary large-scale structures in electron-temperature-gradient (ETG) turbulence is investigated based on gyrofluid simulations in sheared slab geometry. It is found that structural bifurcation to zonal flow dominated or streamer-like states depends on the spectral anisotropy of turbulent ETG fluctuation, which is governed by the magnetic shear. The turbulent electron transport is suppressed by enhanced zonal flows. However, it is still low even if the streamer is formed in ETG turbulence with strong shears. It is shown that the low transport may be related to the secondary excitation of poloidal long-wavelength mode due to the beat wave of the most unstable components or a modulation instability. This large-scale structure with a low frequency and a long wavelength may saturate, or at least contribute to the saturation of ETG fluctuations through a poloidal mode coupling. The result suggests a low fluctuation level in ETG turbulence. 展开更多
关键词 large-scale structures ETG turbulence gyrofluid simulation TOKAMAK
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LARGE-SCALE VORTICAL STRUCTURES PRODUCED BY AN IMPINGING DENSITY JET IN SHALLOW CROSSFLOW
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作者 樊靖郁 王道增 张燕 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第3期363-369,共7页
The large-scale vortical structures produced by an impinging density jet in shallow crossflow were numerically investigated in detail using RNG turbulence model. The scales, formation mechanism and evolution feature o... The large-scale vortical structures produced by an impinging density jet in shallow crossflow were numerically investigated in detail using RNG turbulence model. The scales, formation mechanism and evolution feature of the upstream wall vortex in relation to stagnation point and the Scarf vortex in near field were analyzed. The computed characteristic scales of the upstream vortex show distinguished three-dimensionality and vary with the velocity ratio and the water depth. The Scarf vortex in the near field plays an important role in the lateral concentration distributions of the impinging jet in crossflow. When the velocity ratio is relatively small, there exists a distinct lateral high concentration aggregation zone at the lateral edge between the bottom layer wall jet and the ambient crossflow, which is dominated by the Scarf vortex in the near field. 展开更多
关键词 impinging jet CROSSFLOW large-scale vortical structure concentration distribution
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Free-Interface Dual-Compatibility Modal Synthesis Substructure Method in Large-Scale Structures
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作者 彭桂瀚 林伟 +1 位作者 陈尚鸿 余洁歆 《Transactions of Tianjin University》 EI CAS 2015年第4期347-355,共9页
Free-interface dual-compatibility modal synthesis method(compatibility of both force and displacement on interfaces)is introduced to large-scale civil engineering structure to enhance computation efficiency. The basic... Free-interface dual-compatibility modal synthesis method(compatibility of both force and displacement on interfaces)is introduced to large-scale civil engineering structure to enhance computation efficiency. The basic equations of the method are first set up, and then the mode cut-off principle and the dividing principle are proposed. MATLAB is used for simulation in different frame structures. The simulation results demonstrate the applicability of this substructure method to civil engineering structures and the correctness of the proposed mode cut-off principle. Studies are also conducted on how to divide the whole structure for better computation efficiency while maintaining better precision. It is observed that the geometry and material properties should be considered, and the synthesis results would be more precise when the inflection points of the mode shapes are taken into consideration. Furthermore, the simulation performed on a large-scale high-rise connected structure further proves the feasibility and efficiency of this modal synthesis method compared with the traditional global method. It is also concluded from the simulation results that the fewer number of DOFs in each substructure will result in better computation efficiency, but too many substructures will be time-consuming due to the tedious synthesis procedures. Moreover, the substructures with free interface will introduce errors and reduce the precision dramatically, which should be avoided. 展开更多
关键词 SUBstructurE method dynamic SUBstructurE analysis free-interface dual-compatibility MODAL synthesismethod large-scale CIVIL engineering structure mode CUT-OFF principle
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Fast SSED-MoM /FEM Analysis for Electromagnetic Scattering of Large-Scale Periodic Dielectric Structures
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作者 何小祥 刘辰 杨阳 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2014年第3期255-259,共5页
A hybrid method combining simplified sub-entire domain basis function method of moment with finite element method( SSED-MoM /FEM) is accelerated for electromagnetic( EM) scattering analysis of large-scale periodic str... A hybrid method combining simplified sub-entire domain basis function method of moment with finite element method( SSED-MoM /FEM) is accelerated for electromagnetic( EM) scattering analysis of large-scale periodic structures.The unknowns are reduced sharply with non-uniform mesh in FEM. The computational complexity of the hybrid method is dramatically declined by applying conjugate gradient-fast Fourier transform( CG-FFT) to the integral equations of both electric field and magnetic field. The efficiency is further improved by using OpenMP technique. Numerical results demonstrate that the SSED-MoM /FEM method can be accelerated for more than three thousand times with large-scale periodic structures. 展开更多
关键词 non-uniform mesh conjugate gradient-fast Fourier transform(CG-FFT) OPENMP large-scale periodic structures electromagnetic scattering
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Probing the Large-scale Structure of the Universe Through Gravitational Wave Observations
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作者 Xiaoyun Shao Zhoujian Cao +1 位作者 Xilong Fan Shichao Wu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第1期60-67,共8页
The improvements in the sensitivity of the gravitational wave(GW) network enable the detection of several large redshift GW sources by third-generation GW detectors. These advancements provide an independent method to... The improvements in the sensitivity of the gravitational wave(GW) network enable the detection of several large redshift GW sources by third-generation GW detectors. These advancements provide an independent method to probe the large-scale structure of the universe by using the clustering of the binary black holes(BBHs). The black hole catalogs are complementary to the galaxy catalogs because of large redshifts of GW events, which may imply that BBHs are a better choice than galaxies to probe the large-scale structure of the universe and cosmic evolution over a large redshift range. To probe the large-scale structure, we used the sky position of the BBHs observed by third-generation GW detectors to calculate the angular correlation function and the bias factor of the population of BBHs. This method is also statistically significant as 5000 BBHs are simulated. Moreover, for the third-generation GW detectors, we found that the bias factor can be recovered to within 33% with an observational time of ten years. This method only depends on the GW source-location posteriors;hence, it can be an independent method to reveal the formation mechanisms and origin of the BBH mergers compared to the electromagnetic method. 展开更多
关键词 gravitational waves (cosmology:)large-scale structure of universe black hole physics
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Empirical Analysis of Relationship between Farmers'Income Structure and Consumption in Guizhou Province in the Context of Large-scale Poverty Alleviation
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作者 Wuxu TIAN Jingwei LIU Zhentao WANG 《Asian Agricultural Research》 2020年第9期6-10,共5页
Large-scale poverty alleviation is one of the three major strategic actions of Guizhou Province to plan for leapfrog development.Through building an econometric model,this paper made an empirical analysis of relations... Large-scale poverty alleviation is one of the three major strategic actions of Guizhou Province to plan for leapfrog development.Through building an econometric model,this paper made an empirical analysis of relationship between farmers'income structure and consumption in Guizhou Province in the context of large-scale poverty alleviation.The results show that the wage income and transfer income of rural residents in Guizhou Province have a significant impact on the promotion of their consumption,and the impact of income from household business operation is also significant,but the impact is relatively weak,while the contribution of farmers'property income to their consumption is insufficient.Finally,in view of the problems in the relationship between the income structure and consumption of farmers in Guizhou Province,it came up with policy recommendations including broadening the income channels,increasing farmers'income,improving the income structure,and promoting farmers'consumption. 展开更多
关键词 large-scale poverty alleviation Three rural issues Income structure Consumption structure
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Large-Scale Structure Formation via Quantum Fluctuations and Gravitational Instability
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作者 Fernando Porcelli Giancarlo Scibona 《International Journal of Geosciences》 2014年第6期634-656,共23页
This is a review of the status of the universe as described by the standard cosmological model combined with the inflationary paradigm. Their key features and predictions, consistent with the WMAP (Wilkinson Microwave... This is a review of the status of the universe as described by the standard cosmological model combined with the inflationary paradigm. Their key features and predictions, consistent with the WMAP (Wilkinson Microwave Anisotropies Probe) and Planck Probe 2013 results, provide a significant mechanism to generate the primordial gravitational waves and the density perturbations which grow over time, and later become the large-scale structure of the universe—from the quantum fluctuations in the early era to the structure observed 13.7 billion later, our epoch. In the single field slow-roll paradigm, the primordial quantum fluctuations in the inflaton field itself translate into the curvature and density perturbations which grow over time via gravitational instability. High density regions continuously attract more matter from the surrounding space, the high density regions become more and more dense in time while depleting the low density regions. At late times the highest density regions peaks collapse into the large structure of the universe, whose gravitational instability effects are observed in the clustering features of galaxies in the sky. Thus, the origin of all structure in the universe probably comes from an early era where the universe was filled with a scalar field and nothing else. 展开更多
关键词 large-scale structurE COSMIC INFLATION CMB NON-GAUSSIANITY
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On the Large-Scale Structure of the Universe as given by the Voronoi Diagrams
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作者 L. Zaninetti 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2006年第4期387-395,共9页
The size distributions of 2D and 3D Voronoi cells and of cells of Vp(2, 3),--2D cut of 3D Voronoi diagram--are explored, with the slngle-parameter (re-scaled) gamma distribution playing a central role in the analy... The size distributions of 2D and 3D Voronoi cells and of cells of Vp(2, 3),--2D cut of 3D Voronoi diagram--are explored, with the slngle-parameter (re-scaled) gamma distribution playing a central role in the analytical fitting. Observational evidence for a cellular universe is briefly reviewed. A simulated Vp(2, 3) map with galaxies lying on the cell boundaries is constructed to compare, as regards general appearance, with the observed CfA map of galaxies and voids, the parameters of the simulation being so chosen as to reproduce the largest observed void size. 展开更多
关键词 surveys -- galaxies CLUSTERS general -- (cosmology:) large-scale structure of Universe
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Super-Large-Scale Structures in the Sloan Digital Sky Survey
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作者 Xin-Fa Deng Yi-Qing Chen +1 位作者 Qun Zhang Ji-Zhou He 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2006年第1期35-42,共8页
We study the super-large-scale structures in the Sloan Digital Sky Survey by cluster analysis, and examine the geometry and the properties of the member galaxies. Two subsamples are selected from the SDSS, Subsample 1... We study the super-large-scale structures in the Sloan Digital Sky Survey by cluster analysis, and examine the geometry and the properties of the member galaxies. Two subsamples are selected from the SDSS, Subsample 1 at the celestial equator and Subsample 2 further north. In Subsample 1 we discover two compact super-large-scale structures: the Sloan Great Wall and the CfA Great Wall. The Sloan Great Wall, located at a median redshift of z= 0.07804, has a total length of about 433 Mpc and a mean galaxy density of about six times that of the whole sample. Most of its member galaxies are of medium size and brightness. The CfA Great Wall, located at a median redshift of z = 0.03058, has a total length of about 251 Mpc and includes large percentages of faint and small galaxies and relatively fewer early-type galaxies. 展开更多
关键词 galaxy: distances and redshifts - large-scale structure of universe
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As Could We Assure Safety in Large-Scale Manufacturing of Nanoparticles for the Biomedical Use
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作者 Kirill Serguey Maksimov Serguei Kirillovich Maksimov Nikolay Dmitrievich Soukhov 《Journal of Biomaterials and Nanobiotechnology》 2011年第5期601-613,共13页
Nanoparticles provide great advantages but also great risks. Risks associating with nanoparticles are the problem of all technologies, but they increase in many times in nanotechnologies. Adequate methods of outgoing ... Nanoparticles provide great advantages but also great risks. Risks associating with nanoparticles are the problem of all technologies, but they increase in many times in nanotechnologies. Adequate methods of outgoing production inspection are necessary to solve the problem of risks, and the inspection must be based on the safety standard. Existing safety standard results from a principle of “maximum permissible concentrations or MPC”. This principle is not applicable to nanoparticles, but a safety standard reflecting risks inherent in nanoparticles doesn’t exist. Essence of the risks is illustrated by the example from pharmacology, since its safety assurance is conceptually based on MPC and it has already come against this problem. Possible formula of safety standard for nanoparticles is reflected in many publications, but conventional inspection methods cannot provide its realization, and this gap is an obstacle to assumption of similar formulas. Therefore the development of nanoparticle industry as a whole (also development of the pharmacology in particular) is impossible without the creation of an adequate inspection method. There are suggested new inspection methods founded on the new physical principle and satisfying to the adequate safety standard for nanoparticles. These methods demonstrate that creation of the adequate safety standard and the outgoing production inspection in a large-scale manufacturing of nanoparticles are the solvable problems. However there is a great distance between the physical principle and its hardware realization, and a transition from the principle to the hardware demands great intellectual and material costs. Therefore it is desirable to call attention of the public at large to the necessity of urgent expansions of investigations associated with outgoing inspections in nanoparticles technologies. It is necessary also to attract attention, first, of representatives of state structures controlling approvals of the adequate safety standard to this problem, since it is impossible to compel producers providing the safety without the similar standard, and, second, of leaders of pharmacological industry, since their industry already entered into the nanotechnology era, and they have taken an interest in a forthcoming development of inspection methods. 展开更多
关键词 Risks of NANOpartICLE large-scale MANUFACTURING Adequate SAFETY Standard Outgoing Production Inspection structure and HABIT Scanning ELECTRON Microscopy HABIT Control by Means of Convergent Illuminating ELECTRON Beams SAFETY Assurance in the NANOpartICLE Industry Is a Solvable Problem
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Observational Features of Large-Scale Structures as Revealed by the Catastrophe Model of Solar Eruptions
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作者 Jun Lin National Astronomical Observatories/Yunnan Observatory, Chinese Academy of Sciences, Kunming 650011 Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2007年第4期457-476,共20页
Large-scale magnetic structures are the main carrier of major eruptions in the solar atmosphere. These structures are rooted in the photosphere and are driven by the unceasing motion of the photospheric material throu... Large-scale magnetic structures are the main carrier of major eruptions in the solar atmosphere. These structures are rooted in the photosphere and are driven by the unceasing motion of the photospheric material through a series of equilibrium configurations. The motion brings energy into the coronal magnetic field until the system ceases to be in equilibrium. The catastrophe theory for solar eruptions indicates that loss of mechanical equilibrium constitutes the main trigger mechanism of major eruptions, usually shown up as solar flares, eruptive prominences, and coronal mass ejections (CMEs). Magnetic reconnection which takes place at the very beginning of the eruption as a result of plasma instabilities/turbulence inside the current sheet, converts magnetic energy into heating and kinetic energy that are responsible for solar flares, and for accelerating both plasma ejecta (flows and CMEs) and energetic particles. Various manifestations are thus related to one another, and the physics behind these relationships is catastrophe and magnetic reconnection. This work reports on recent progress in both theoretical research and observations on eruptive phenomena showing the above manifestations. We start by displaying the properties of large-scale structures in the corona and the related magnetic fields prior to an eruption, and show various morphological features of the disrupting magnetic fields. Then, in the framework of the catastrophe theory, we look into the physics behind those features investigated in a succession of previous works, and discuss the approaches they used. 展开更多
关键词 Sun: large-scale magnetic structures - Sun: eruptive processes - Sun: theory and observations - magnetic reconnection and current sheets
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Assessing the influence of harvesting intensities on structural diversity of forests in south-west Germany 被引量:1
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作者 Felix Storch Gerald Kadler Jürgen Bauhus 《Forest Ecosystems》 SCIE CSCD 2019年第3期249-260,共12页
Background: To increase ecosystem resilience and biodiversity, the maintenance and improvement of structural and compositional diversity of forests has become an important goal in forest management for many forest own... Background: To increase ecosystem resilience and biodiversity, the maintenance and improvement of structural and compositional diversity of forests has become an important goal in forest management for many forest owners and jurisdictions. At the same time, future harvesting intensity (HI) may increase to meet the demand for woody biomass by an increasing bioeconomy sector. Yet, the influence of HI on forest structural diversity is largely unknown. Here, we address this issue by analyzing the relationship between HI and structural diversity based on large-scale national forest inventory (NFI) data, where the latter is quantified using a previously developed Forest Structure Index and HI is expressed as wood volume removal during the period 2002-2012 for the same inventory plots. Results: Our results show a surprisingly small impact of harvesting intensity on changes in structural diversity for most of the analysed types of forests. Only intense harvesting (> 80%-90% of initial growing stock) led to a significant reduction in structural diversity. At low to moderate HI most aspects of structural diversity were positively influenced. Only the quadratic mean DBH and the volume of large trees (≥ 40 cm DBH) were substantially negatively influenced at HI > 60% and 70% of initial growing stock, respectively. Conclusions: In several forest types, HI could be increased without a reduction in overall structural diversity. Hence, structural diversity in these selectively managed forests appears to be a very resistant forest property in relation to HI. Other indicators at stand and landscape scale may be needed to adjust levels of HI that are suited to maintain forest biodiversity. 展开更多
关键词 large-scale INVENTORY structural DIVERSITY index HARVESTING intensity Changes in structural DIVERSITY
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Research and Analysis of Structural Hole and Matching Coefficient 被引量:1
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作者 Penghua Cai Hai Zhao +3 位作者 Hong Liu Rong Pan Zheng Liu Hui Li 《Journal of Software Engineering and Applications》 2010年第11期1080-1087,共8页
Measure is a map from the reality or experimental world to the mathematical world, through which people can more easily understand the properties of entities and the relationship between them. But the traditional soft... Measure is a map from the reality or experimental world to the mathematical world, through which people can more easily understand the properties of entities and the relationship between them. But the traditional software measurement methods have been unable to effectively measure this large-scale software. Therefore, trustworthy measurement gives an accurate measurement to these emerging features, providing valuable perspectives and different research dimensions to understand software systems. The paper introduces the complex network theory to software measurement methods and proposes a statistical measurement methodology. First we study the basic parameters of the complex network, and then introduce two new measurement parameters: structural holes, matching coefficient. 展开更多
关键词 large-scale SOFTWARE TRUSTWORTHY Measurement structural HOLES MATCHING COEFFICIENT
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