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NeoMinkowskian Cosmological Black Hole, Poincaré’s Gravific Electron and Density of CBR
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作者 Yves Pierseaux 《Journal of Modern Physics》 2020年第2期237-280,共44页
In the previous paper (JMP 2014) we showed that there exists a NeoMinkowskian Gravitational Expanding Solution of GR (General Relativity) with CC (Cosmological Constant). We prove now that NeoMinkowskian Vacuum (non-b... In the previous paper (JMP 2014) we showed that there exists a NeoMinkowskian Gravitational Expanding Solution of GR (General Relativity) with CC (Cosmological Constant). We prove now that NeoMinkowskian Vacuum (non-baryonic Fluid), with gravitational (first) density (dark energy) and gravitational waves (at light speed), corresponds to the Gravitation Field of a Cosmological Black Hole (CBH). The latter predicts furthermore a basic emission of Radiation (CBR) from Hubble spherical singular Horizon to the inside of CBH (unlike Hawking’s emission) at an initial singular time. Our solution is then compatible with a well-tempered Big Bang and Expanding Universe (Escher’s Figure, see Penrose, 3) but incompatible with inflation. The latter is based on Hypothesis of a so-called Planck’s particle (Lemaitre’s primitive atom) characterized by a so-called Planck length. We prove that we can short-circuit this unstable particle with a stable cosmological Poincaré’s electron with gravific pressure. It is well known that electron is a stranger in usual Minkowskian vacuum (dixit Einstein). The stranger electron can be perfectly integrated in NeoMinkowskian Radiation fluid and then also (with its mass, charge and wavelength) in (second density of) CBR. Everything happens as if the leptonic mass of the electron were induced by our cosmological field. The unexpected cosmological model proposed here is the only one that predicts numerical values of (second) density and temperature of CBR very close to the observed (COBE) values. 展开更多
关键词 COSMOLOGICAL Constant General Relativity Minkowskian Metric Cosmolog-ical Black Hole Tachyons Hyperbolic Horizon density of Vacuum density of CBR Poincarés Gravitational Waves Poincarés ELECTRON DE Broglies Wave Electrodynamics DE Broglies Subquantum Substratum
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Ultrafast Laser Energy Density and Retinal Absorption Cross-Section Determination by Saturable Absorption Measurements
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作者 Alfons Penzkofer Meike Luck +1 位作者 Tilo Mathes Peter Hegemann 《Journal of Analytical Sciences, Methods and Instrumentation》 2014年第1期19-26,共8页
Laser pulse nonlinear transmission measurements through saturable absorbers of known absorption parameters allow the measurement of their energy density. On the other hand, nonlinear transmission measurements of laser... Laser pulse nonlinear transmission measurements through saturable absorbers of known absorption parameters allow the measurement of their energy density. On the other hand, nonlinear transmission measurements of laser pulses of known energy density through absorbing media allow their absorption parameter determination. The peak energy density w0P of second harmonic pulses of a mode-locked titanium sapphire laser at wavelength λP = 400 nm is determined by nonlinear energy transmission measurement TE through the dye ADS084BE (1,4-bis(9-ethyl-3-car-bazovinylene)-2-methoxy-5-(2’-ethyl-hexyloxy)-benzene) in tetrahydrofuran. TE(w0P) calibration curves are calculated for laser pulse peak energy density reading w0P from measured pulse energy transmissions TE. The ground-state absorption cross-section σP and the excited-state absorption cross-section σex at λP, and the number density N0 of the retinal Schiff base isoform RetA in pH 7.4 buffer of the blue-light adapted recombinant rhodopsin fragment of the histidine kinase rhodopsin HKR1 from Chlamydomonas reinhardtii were determined by picosecond titanium sapphire second harmonic laser pulse energy transmission measurement TE through RetA as a function of laser input peak energy density w0P. The complete absorption cross-section spectrum 展开更多
关键词 Laser Pulse Peak Energy density DETERMINATION Ground-State ABSORPTION CROSS-SECTION DETERMINATION Excited-State ABSORPTION CROSS-SECTION DETERMINATION Saturable ABSORPTION ADS084BE Dye Histidine Kinase RHODOPSIN HKR1 RETINAL Schiff Base RetA Cofactor Number density DETERMINATION
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A Combined Heterotic String and Kähler Manifold Elucidation of Ordinary Energy,Dark Matter,Olbers’s Paradox and Pure Dark Energy Density of the Cosmos
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作者 Mohamed S.El Naschie 《Journal of Modern Physics》 2017年第7期1101-1118,共18页
We utilize the topological-geometrical structure imposed by the Heterotic superstring theory on spacetime in conjunction with the K3 K&auml;hler manifold to explain the mysterious nature of dark matter and its cou... We utilize the topological-geometrical structure imposed by the Heterotic superstring theory on spacetime in conjunction with the K3 K&auml;hler manifold to explain the mysterious nature of dark matter and its coupling to the pure dark energy density of the cosmos. The analogous situations in the case of a Kerr black hole as well as the redundant components of the Riemannian tensor are pointed out and the final result was found to be in complete agreement with all previous theoretical ones as well as all recent accurate measurements and cosmic observations. We conclude by commenting briefly on the Cantorian model of Zitterbewegung and the connection between Olbers’s paradox and dark energy. 展开更多
关键词 Heterotic Strings K3 Kahler Manifold Dark Matter Pure Heterotic Dark Energy Einsteins Relativity Accelerated Cosmic Expansion Negative Gravity Fractal Spacetime E-Infinity Theory Kerr Black Holes Geometry Kaluza-Klein Theory Dvoretzkys Theorem Empty Set Zero Set Connes Noncommutative Geometry tHooft Renormalon STATE Vector Reduction density Matrix tHooft Fractal Spacetime Transfinite Cellular Automata Interpretation of Quantum Mechanics ZITTERBEWEGUNG Olberss Dark Sky Paradox
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Crustal density structure of the southern segment of the Liaocheng-Lankao fault, China 被引量:1
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作者 Lei Jiang Lanbo Liu +4 位作者 Zhiping Xu Xiaoguo Deng Lipu Yang Wei Xiong Shunqiang Xu 《Geodesy and Geodynamics》 2019年第5期347-355,共9页
The 1:200,000 middle-large scale Bouguer gravity anomaly data covering the southern segment of the Liaocheng-Lankao fault(SLLF)and its vicinity are analyzed with two methods.First,the Bouguer gravity anomaly data are ... The 1:200,000 middle-large scale Bouguer gravity anomaly data covering the southern segment of the Liaocheng-Lankao fault(SLLF)and its vicinity are analyzed with two methods.First,the Bouguer gravity anomaly data are decomposed by two-dimensional(2 D)wavelet to make the family of multi-scale modes correspond with density structure at different depths.Second,a two and half dimension(2.5 D)human-computer interaction inversion of the Bouguer gravity anomaly data are conducted with the constraints provided by two deep seismic sounding profiles(DSS1 and DSS2)crossing the study area to get the crustal density profiles.Based on the integrated study,we can draw the following conclusions:1)SLLF appears to be a deep fault with almost vertical dipping and rooted into the uppermost mantle;2)In the middle to upper crust SLLF shows an clear turning patterns and segmentation features;3)In the study area the epicentral distributions of the precisely re-located small earthquakes and the historical large earthquakes have a good correspondence with the turning patterns and segmentation features of SLLF;and 4)The results of the horizontal slices from 2 D wavelet decomposition show that there are significant differences in the density structure on the two sides of the fault.A well-defined concave structure with low density exists in the upper crust of the Dongming Depression on the west side of the fault,with the concave center being estimated at a depth of about 8 km.In contrast,the upper crust on the east side presents a relative thinner pattern in depth with a bit higher density.Meanwhile,the low-density structure in the middle crust underneath the fault is presumably caused by the uplift of the upper mantle materials and their intrusion along the deep rupture system.This paper clarified the inconsistency of fault system and epicenters of small earthquakes from upper to lower crust.The results indicated that the fault system plays an important governing role to the seismicity in this area. 展开更多
关键词 Southern SEGMENT of the Liaocheng-Lankao fault(SLLF) Bouguer gravity ANOMALIES density structure Dongming depression MULTI-SCALE wavelet decomposition Epicenters of small EARTHQUAKES
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The Pursuit of Fallacy in Density Functional Theory: The Quest for Exchange and Correlation, the Rigorous Treatment of Exchange in the Kohn-Sham Formalism and the Continuing Search for Correlation
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作者 A. Gonis 《World Journal of Condensed Matter Physics》 2014年第3期200-225,共26页
As pointed out in the paper preceding this one, in the case of functionals whose independent variable must obey conditions of integral normalization, conventional functional differentiation, defined in terms of an arb... As pointed out in the paper preceding this one, in the case of functionals whose independent variable must obey conditions of integral normalization, conventional functional differentiation, defined in terms of an arbitrary test function, is generally inapplicable and functional derivatives with respect to the density must be evaluated through the alternative and widely used limiting procedure based on the Dirac delta function. This leads to the determination of the rate of change of the dependent variable with respect to its independent variable at each isolated pair, , that may not be part of a functional (a set of ordered pairs). This extends the concept of functional derivative to expectation values of operators with respect to wave functions leading to a density even if the wave functions (and expectation values) do not form functionals. This new formulation of functional differentiation forms the basis for the study of the mathematical integrity of a number of concepts in density functional theory (DFT) such as the existence of a universal functional of the density, of orbital-free density functional theory, the derivative discontinuity of the exchange and correlation functional and the extension of DFT to open systems characterized by densities with fractional normalization. It is shown that no universal functional exists but, rather, a universal process based only on the density and independent of the possible existence of a potential, leads to unique functionals of the density determined through the minimization procedure of the constrained search. The mathematical integrity of two methodologies proposed for the treatment of the Coulomb interaction, the self-interaction free method and the optimized effective potential method is examined and the methodologies are compared in terms of numerical calculations. As emerges from this analysis, the optimized effective potential method is found to be numerically approximate but formally invalid, contrary to the rigorously exact results of the self-interaction-free method. 展开更多
关键词 density FUNCTIONAL THEORY Variational Properties of density FUNCTIONAL THEORY Self-Interaction Error Optimized Effective Potential FUNCTIONAL DERIVATIVE Parametric DERIVATIVE FUNCTIONAL Rate of Change DERIVATIVE Discontinuity Orbital-Free density FUNCTIONAL THEORY EXCHANGE and CORRELATION FUNCTIONAL
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Analyzing Population Density Disparity in China with GIS-automated Regionalization: The Hu Line Revisited 被引量:5
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作者 WANG Fahui LIU Cuiling XU Yaping 《Chinese Geographical Science》 SCIE CSCD 2019年第4期541-552,共12页
The famous ’Hu Line’, proposed by Hu Huanyong in 1935, divided China into two regions(southeast and northwest) of comparable area size but drastically different in population. However, the classic Hu Line was derive... The famous ’Hu Line’, proposed by Hu Huanyong in 1935, divided China into two regions(southeast and northwest) of comparable area size but drastically different in population. However, the classic Hu Line was derived manually in absence of reliable census data and computational technologies of modern days. It has been subject to criticism of lack of scientific rigor and accuracy. This research uses a GIS-automated regionalization method, termed REDCAP(Regionalization with Dynamically Constrained Agglomerative Clustering and Partitioning), to reconstruct the demarcation line based on the 2010 county-level census data in China. The results show that the logarithmic transformation of population density is a better measure of attributive homogeneity in derived regions than density itself, and produces two regions of nearly identical area size and greater contrast in population. Specifically, the revised Hu Line by Hu Huanyong in 1990 had the southeast region with 94.4% of total population and 42.9% of total land, and our delineation line yields a southeast region with 97.4% population and 50.8% land. Therefore, the population density ratio of the two regions is 27.1 by our line, much higher than the ratio of 22.4 by the Hu Line, and thus outperforms the Hu Line in deriving regions of maximum density contrast with comparable area size. Furthermore, more regions are delineated to further advance our understanding of population distribution disparity in China. 展开更多
关键词 HU LINE regional population density DISPARITY GIS-automated REGIONALIZATION REDCAP (Regionalization with Dynamically Constrained Agglomerative Clustering and Partitioning) China
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Genetic Worth Effect Models for Boreal Conifers and Their Utility When Integrated into Density Management Decision-Support Systems 被引量:1
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作者 Peter F. Newton 《Open Journal of Forestry》 2015年第1期105-115,共11页
Based on approaches deduced from previous research findings and empirical observations from density control experiments, genetic worth effect response models were developed for black spruce (Picea mariana (Mill) BSP.)... Based on approaches deduced from previous research findings and empirical observations from density control experiments, genetic worth effect response models were developed for black spruce (Picea mariana (Mill) BSP.) and jack pine (Pinus banksiana Lamb.) plantations. The models accounted for the increased rate of stand development arising from the planting of genetically-improved stock through temporal adjustments to the species-specific site-based mean dominant height-age functions. The models utilized a relative height growth modifier based on known estimates of genetic gain. The models also incorporated a phenotypic juvenile age-mature age correlation function in order to account for the intrinsic temporal decline in the magnitude of genetic worth effects throughout the rotation. Integrating the functions into algorithmic variants of structural stand density management models produced stand development patterns that were consistent with axioms of even-aged stand dynamics. 展开更多
关键词 PICEA MARIANA Pinus banksiana Structural Stand density Management MODELS Phenotypic Juvenile Age-Mature Age Correlation Canadian BOREAL Forest Region
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Time Dimension and Ordinary Cosmic Energy Density Are Fractal Effects
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作者 Mohamed S. El Naschie 《Journal of Quantum Information Science》 2018年第2期47-51,共5页
In a short, neat and credible analysis, it is established that time is a fractal effect of the Cantor set-like topology of micro spacetime. This effect as well as the ordinary cosmic energy density of the universe is ... In a short, neat and credible analysis, it is established that time is a fractal effect of the Cantor set-like topology of micro spacetime. This effect as well as the ordinary cosmic energy density of the universe is shown to be a direct consequence of Hardy’s probability of quantum entanglement. Finally and as a general conclusion, we point out the importance of understanding the fractal origin of time as well as spacetime for resolving certain types of paradoxes arising in quantum information science. 展开更多
关键词 Random CANTOR Sets E-INFINITY EINSTEIN SPACETIME Cantorian SPACETIME Penrose Universe 'thooft Renormalon Dark ENERGY Ordinary ENERGY density Correlation Hardys Quantum Entanglement
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Dependence of the Yield of Alfalfa on Plant Density and Diet
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作者 Alizade Alibala Zamanov Pasha +1 位作者 Zamanova Azada Iskenderov Subaxat 《American Journal of Plant Sciences》 2017年第11期2722-2731,共10页
In this study, under conditions of enclosed soil, experiments were conducted on the dependence of the yield (weight of green mass) of alfalfa (Medicago) on plant density and diet. The experiments were carried out in f... In this study, under conditions of enclosed soil, experiments were conducted on the dependence of the yield (weight of green mass) of alfalfa (Medicago) on plant density and diet. The experiments were carried out in five variants, in different values of the integrated density of plants and lasted 89 days. As a feed, specially prepared bio fertilizer was used and added with the calculation of 1 kg per 1 m2 of area. In the corresponding control variants, bio fertilizer was not used. Analysis of the experimental results showed that the feeding regime made it possible to obtain a maximum yield at higher integral density. At the same time, the increase in the weight of green mass when using bio fertilizers was about 36%. 展开更多
关键词 YIELD density of Standing Integral density Competition between NEIGHBORS Weight of Green Mass Differential density BIOFERTILIZER Cultivated Plant DIET ARABLE Fields
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Revision of CG Flash Density Based on Lightning Location Data
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作者 Peng Guoping 《Meteorological and Environmental Research》 CAS 2019年第2期69-72,77,共5页
Using the data of the Lightning Location System( LLS) over Hubei Province,through the analysis of the distribution characteristics of CG( Cloud-to-Ground) flash density in 2015,it was found that the layout of the dete... Using the data of the Lightning Location System( LLS) over Hubei Province,through the analysis of the distribution characteristics of CG( Cloud-to-Ground) flash density in 2015,it was found that the layout of the detection station had influence on the spatial distribution of lightning.Grid CG flash density data were used to characterize the spatial distribution of the CG flash,and station distance factor was used to characterize the detection station layout. The result showed that there existed negative correlation between density and factor,significant correlation between the density component and the factor for the lightning current amplitude of 5 to 30 kA,and insignificant correlation between >30 kA of density component and factor. So it is necessary to revise the density to eliminate the influence of the station layout. On the basis of the linear regression method and its residual theory,the revision model of the grid CG flash density and the statistical model of relative detection efficiency were established. The result consistency of segment and non-segmented revision of the density was verified. Through the contrastive analysis of theoretical detection efficiency and relative detection efficiency,the feasibility for revision method of CG flash density and the statistical method of relative detection efficiency was also verified. 展开更多
关键词 LIGHTNING location system LATITUDE and LONGITUDE grid REVISION of CG flash density Detection efficiency Regression analysis Residual theory
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The Gap Labelling Integrated Density of States for a Quasi Crystal Universe Is Identical to the Observed 4.5 Percent Ordinary Energy Density of the Cosmos 被引量:2
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作者 Mohamed S. El Naschie 《Natural Science》 2014年第16期1259-1265,共7页
Condense matter methods and mathematical models used in solving problems in solid state physics are transformed to high energy quantum cosmology in order to estimate the magnitude of the missing dark energy of the uni... Condense matter methods and mathematical models used in solving problems in solid state physics are transformed to high energy quantum cosmology in order to estimate the magnitude of the missing dark energy of the universe. Looking at the problem from this novel viewpoint was rewarded by a rather unexpected result, namely that the gap labelling method of integrated density of states for three dimensional icosahedral quasicrystals is identical to the previously measured and theoretically concluded ordinary energy density of the universe, namely a mere 4.5 percent of Einstein’s energy density, i.e. E(O) = mc2/22 where E is the energy, m is the mass and c is the speed of light. Consequently we conclude that the missing dark energy density must be E(D) = 1 - E(O) = mc2(21/22) in agreement with all known cosmological measurements and observations. This result could also be interpreted as a strong evidence for the self similarity of the geometry of spacetime, which is an expression of its basic fractal nature. 展开更多
关键词 E-INFINITY Theory Fractal-Witten M-THEORY GAP Labelling Theorem density of States Dark Energy density Noncommutative Geometry K-THEORY Dimension Group
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Concealed porphyry delineation based on nonlinear three-dimensional densitydifference inversion: An example in the Beiya mine area, Western Yunnan, China
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作者 Jian Yang Sheng-xian Liang +3 位作者 Qiao Wang Wei Zhang Jing Guo Guo-zhong Liao 《China Geology》 2019年第3期342-353,共12页
Intermediate acid-complex rock masses with low-density characteristics are the most important prospecting sign in the Beiya area, of western Yunnan province, and provide a physical basis for good gravity exploration. ... Intermediate acid-complex rock masses with low-density characteristics are the most important prospecting sign in the Beiya area, of western Yunnan province, and provide a physical basis for good gravity exploration. It is usually difficult to obtaining solutions in connection with actual geological situations due to the ambiguity of the conventional gravity-processing results and lack of deep constraints. Thus, the three-dimensional (3D) inversion technology is considered as the main channel for reducing the number of solutions and improving the vertical resolution at the current stage. The current study starts from a model test and performs nonlinear 3D density-difference inversion called “model likelihood exploration”, which performs 3D inversion imaging and inversion of the known model while considering the topographic effects. The inversion results are highly consistent with those of the known models. Simultaneously, we consider the Beiya gold mine in Yunnan as an example. The nonlinear 3D densitydifference inversion technology, which is restricted by geological information, is explored to obtain the 3D density body structure below 5 km in the mine area, and the 3D structure of the deep and concealed rock masses are obtained using the density constraints of the intermediate-acid-complex rock masses. The results are well consistent with the surface geological masses and drilling-controlled deep geological masses. The model test and examples both show that the 3D density-difference nonlinear inversion technology can reduce inversion ambiguity, improve resolution, optimize the inversion results, and realize “transparency” in deeply concealed rock masses in ore-concentrated areas,which is useful in guiding the deep ore prospecting. 展开更多
关键词 THREE-DIMENSIONAL density INVERSION Concealed PORPHYRY Gold DEPOSIT Mineral resources exploration engineering Beiya mine area YUNNAN Province China
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Density structure of the crust in the Emeishan large igneous province revealed by the Lijiang-Guiyang gravity profile 被引量:1
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作者 Xi Zhang Peng Wang +3 位作者 Tao Xu Yun Chen José Badal JiWen Teng 《Earth and Planetary Physics》 2018年第1期74-81,共8页
The Emeishan large igneous province(hereafter named by its acronym ELIP) is the first accepted large igneous region in China.The current study tries to reconstruct the density structure of the crust in this region. Fo... The Emeishan large igneous province(hereafter named by its acronym ELIP) is the first accepted large igneous region in China.The current study tries to reconstruct the density structure of the crust in this region. For this purpose, we conducted the gravity survey along an 800-km-long profile, which stretched laterally along the latitude 27°N from Lijiang(Yunnan province) to Guiyang(Guizhou province). The fieldwork included 338 gravity measurements distributed from the inner zone to the outer zone of the mantle plume head.After a series of gravity reductions, we calculated the Bouguer gravity anomaly and then constructed the density model for ELIP by iterative forward modeling from an initial density model tightly constrained by wide-angle seismic reflection data. The topography of the Moho, here physically interpreted as a density discontinuity of ~0.4 g·cm^(–3), gradually rises from the inner zone(~50 km deep) to the outer zone(~40 km), describes a thicker crust in the inner zone than in any other segment of the profile and largely reproduces the shape of the Bouguer gravity anomaly curve. Both the Bouguer gravity and the density structure show significant differences with respect to the inner zone and the other two zones of ELIP according to the commonly accepted partition of the Emeishan area. A thicker and denser middle-lower crust seems to be the main feature of the western section of the profile, which is likely related to its mafic magmatic composition due to magmatic underplating of the Permian mantle plume. 展开更多
关键词 Bouguer GRAVITY seismic reflection data forward modeling CRUSTAL density structure EMEISHAN large IGNEOUS province South China
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Biomass Production of Cup Plant (<i>Silphium perfoliatum</i>L.) in Response to Variation in Plant Population Density in the North Central USA 被引量:1
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作者 Arvid Boe Kenneth A. Albrecht +1 位作者 Paul J. Johnson Jixiang Wu 《American Journal of Plant Sciences》 2019年第6期904-910,共7页
The North American genus Silphium is receiving global attention for its potential in the development of new food, forage, and industrial crops, including cellulosic biomass for biofuel. Little is known about the effec... The North American genus Silphium is receiving global attention for its potential in the development of new food, forage, and industrial crops, including cellulosic biomass for biofuel. Little is known about the effect of plant population density on biomass production in large, coarse perennial forbs. Our objective was to evaluate the effect of variation in plant density on biomass production and stand morphology of cup plant (Silphium perfoliatum L.). Plant population densities of 17,000, 34,000, and 68,000 plants ha-1 were evaluated for biomass production in a single-harvest per annum system for three years at Brookings, SD and Arlington, WI. Biomass increased linearly by 43% between the low and high density at Brookings;whereas, at Arlington, response to variation in plant density was year dependent. Shoots plant-1 was inversely related to plant density with linear regression explaining >95% of the variation. Our results strongly suggested that further studies of effects of plant population density on biomass production in cup plant should include evaluation of, in addition to, densities higher than 68,000 plants ha-1. 展开更多
关键词 Biofuel Shoot density SHOOTS Plant-1 Stand Morphology CUP PLANT Moth Eucosma giganteana Riley Biotic STRESS Abiotic STRESS
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Kernel Density Estimation of Tropical Cyclone Frequencies in the North Atlantic Basin 被引量:1
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作者 Timothy A. Joyner Robert V. Rohli 《International Journal of Geosciences》 2010年第3期121-129,共9页
Previous research has identified specific areas of frequent tropical cyclone activity in the North Atlantic basin. This study examines long-term and decadal spatio-temporal patterns of Atlantic tropical cyclone freque... Previous research has identified specific areas of frequent tropical cyclone activity in the North Atlantic basin. This study examines long-term and decadal spatio-temporal patterns of Atlantic tropical cyclone frequencies from 1944 to 2009, and analyzes categorical and decadal centroid patterns using kernel density estimation (KDE) and centrographic statistics. Results corroborate previous research which has suggested that the Bermuda-Azores anticyclone plays an integral role in the direction of tropical cyclone tracks. Other teleconnections such as the North Atlantic Oscillation (NAO) may also have an impact on tropical cyclone tracks, but at a different temporal resolution. Results expand on existing knowledge of the spatial trends of tropical cyclones based on storm category and time through the use of spatial statistics. Overall, location of peak frequency varies by tropical cyclone category, with stronger storms being more concentrated in narrow regions of the southern Caribbean Sea and Gulf of Mexico, while weaker storms occur in a much larger area that encompasses much of the Caribbean Sea, Gulf of Mexico, and Atlantic Ocean off of the east coast of the United States. Additionally, the decadal centroids of tropical cyclone tracks have oscillated over a large area of the Atlantic Ocean for much of recorded history. Data collected since 1944 can be analyzed confidently to reveal these patterns. 展开更多
关键词 ATLANTIC Tropical Cyclone Frequencies Decadal Centroid Patterns Kernel density Estimation (KDE) Centrographic Statistics Bermuda-Azores ANTICYCLONE TELECONNECTIONS
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Investigation of Structural and Electronic Properties of [Tris(Benzene-1,2-Dithiolato)M]<sup>3-</sup>(M = V, Cr, Mn, Fe and Co) Complexes: A Spectroscopic and Density Functional Theoretical Study
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作者 Mohammad A.Matin Md.Abdur Rahman 《Advances in Chemical Engineering and Science》 2019年第4期317-332,共16页
In this study, the first raw transition metals from V to Co complexes with benzene-1,2-dithiolate (L2-) ligand have been studied theoretically to elucidate the geometry, electronic structure and spectroscopic properti... In this study, the first raw transition metals from V to Co complexes with benzene-1,2-dithiolate (L2-) ligand have been studied theoretically to elucidate the geometry, electronic structure and spectroscopic properties of the complexes. Density Functional Theory (DFT) and Time-Dependent Density Functional Theory (TD-DFT) methods have been used. The ground state geometries, binding energies, spectral properties (UV-vis), frontier molecular orbitals (FMOs) analysis, charge analysis and natural bond orbital (NBO) have been investigated. The geometrical parameters are in good agreement with the available experimental data. The metal-ligand binding energies are 1 order of magnitude larger than the physisorption energy of a benzene-1, 2-dthiolate molecule on a metallic surface. The electronic structures of the first raw transition metal series from V to Co have been elucidated by UV-vis spectroscopic using DFT calculations. In accordance with experiment the calculated electronic spectra of these tris complexes show bands at 522, 565, 559, 546 and 863 nm for V3+, Cr3+, Mn3+, Fe3+ and Co3+ respectively which are mainly attributed to ligand to metal charge transfer (LMCT) transitions. The electronic properties analysis shows that the highest occupied molecular orbital (HOMO) is mainly centered on metal coordinated sulfur atoms whereas the lowest unoccupied molecular orbital (LUMO) is mainly located on the metal surface. From calculation of intramolecular interactions and electron delocalization by natural bond orbital (NBO) analysis, the stability of the complexes was estimated. The NBO results showed significant charge transfer from sulfur to central metal ions in the complexes, as well as to the benzene. The calculated charges on metal ions are also reported at various charge schemes. The calculations show encouraging agreement with the available experimental data. 展开更多
关键词 Transition Metal Time Dependent density Functional Theory (TD-DFT) Binding Energy Spectroscopy Electronic Properties Tris(Benzene-1 2-Dithiolato) Coordination Complex
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Outlier detection based on multi-dimensional clustering and local density
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作者 SHOU Zhao-yu LI Meng-ya LI Si-min 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第6期1299-1306,共8页
Outlier detection is an important task in data mining. In fact, it is difficult to find the clustering centers in some sophisticated multidimensional datasets and to measure the deviation degree of each potential outl... Outlier detection is an important task in data mining. In fact, it is difficult to find the clustering centers in some sophisticated multidimensional datasets and to measure the deviation degree of each potential outlier. In this work, an effective outlier detection method based on multi-dimensional clustering and local density(ODBMCLD) is proposed. ODBMCLD firstly identifies the center objects by the local density peak of data objects, and clusters the whole dataset based on the center objects. Then, outlier objects belonging to different clusters will be marked as candidates of abnormal data. Finally, the top N points among these abnormal candidates are chosen as final anomaly objects with high outlier factors. The feasibility and effectiveness of the method are verified by experiments. 展开更多
关键词 data MINING OUTLIER DETECTION OUTLIER DETECTION method based on MULTI-DIMENSIONAL CLUSTERING and local density (ODBMCLD) algorithm deviation DEGREE
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A PAT STUDY OF INFLUENCES OF PRECIPITATION ON DEFECTS AND ELECTRONIC DENSITY IN Al-Li-Cu-Mg-Zr ALLOYS 被引量:2
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作者 Wu, WM Gao, YJ +4 位作者 Luo, LX Deng, W Xu, SJ Zhong, XP Jiang, XJ 《中国有色金属学会会刊:英文版》 CSCD 1997年第1期43-46,共4页
APATSTUDYOFINFLUENCESOFPRECIPITATIONONDEFECTSANDELECTRONICDENSITYINAlLiCuMgZrALLOYS①WuWeiming,GaoYingjun,Luo... APATSTUDYOFINFLUENCESOFPRECIPITATIONONDEFECTSANDELECTRONICDENSITYINAlLiCuMgZrALLOYS①WuWeiming,GaoYingjun,LuoLixiong,DengW... 展开更多
关键词 positron lifetime spectra Al Li Cu Mg ZR alloy ageing PRECIPITATION DEFECTS bulk ELECTRONIC density
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First-principles prediction of shock Hugoniot curves of boron,aluminum,and silicon from stochastic density functional theory
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作者 Tao Chen Qianrui Liu +1 位作者 Chang Gao Mohan Chen 《Matter and Radiation at Extremes》 2025年第5期73-83,共11页
By adopting stochastic density functional theory(SDFT)and mixed stochastic-deterministic density functional theory(MDFT)methods,we perform first-principles calculations to predict the shock Hugoniot curves of boron(pr... By adopting stochastic density functional theory(SDFT)and mixed stochastic-deterministic density functional theory(MDFT)methods,we perform first-principles calculations to predict the shock Hugoniot curves of boron(pressure P=7.9×10^(3)-1.6×10^(6) GPa and temperature T=25-2800 eV),silicon(P=2.6×10^(3)-7.9×10^(5) GPa and T=21.5-1393 eV),and aluminum(P=5.2×10^(3)-9.0×10^(5) GPa and T=25-1393 eV)over wide ranges of pressure and temperature.In particular,we systematically investigate the impact of different cutoff radii in norm-conserving pseudopotentials on the calculated properties at elevated temperatures,such as pressure,ionization energy,and equation of state.By comparing the SDFT and MDFT results with those of other first-principles methods,such as extended first-principles molecular dynamics and path integral Monte Carlo methods,we find that the SDFT and MDFT methods show satisfactory precision,which advances our understanding of first-principles methods when applied to studies of matter at extremely high pressures and temperatures. 展开更多
关键词 mixed stochastic deterministic density functional theory BORON shock hugoniot curves stochastic density functional theory stochastic density functional theory sdft ALUMINUM SILICON first principles calculations
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Fast density peak-based clustering algorithm for multiple extended target tracking 被引量:4
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作者 SHEN Xinglin SONG Zhiyong +1 位作者 FAN Hongqi FU Qiang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第3期435-447,共13页
The key challenge of the extended target probability hypothesis density (ET-PHD) filter is to reduce the computational complexity by using a subset to approximate the full set of partitions. In this paper, the influen... The key challenge of the extended target probability hypothesis density (ET-PHD) filter is to reduce the computational complexity by using a subset to approximate the full set of partitions. In this paper, the influence for the tracking results of different partitions is analyzed, and the form of the most informative partition is obtained. Then, a fast density peak-based clustering (FDPC) partitioning algorithm is applied to the measurement set partitioning. Since only one partition of the measurement set is used, the ET-PHD filter based on FDPC partitioning has lower computational complexity than the other ET-PHD filters. As FDPC partitioning is able to remove the spatially close clutter-generated measurements, the ET-PHD filter based on FDPC partitioning has good tracking performance in the scenario with more clutter-generated measurements. The simulation results show that the proposed algorithm can get the most informative partition and obviously reduce computational burden without losing tracking performance. As the number of clutter-generated measurements increased, the ET-PHD filter based on FDPC partitioning has better tracking performance than other ET-PHD filters. The FDPC algorithm will play an important role in the engineering realization of the multiple extended target tracking filter. 展开更多
关键词 FAST density peak-based clustering (FDPC) MULTIPLE extended target partition probability hypothesis density (PHD) filter track.
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