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New construction of mutually unbiased bases for odd-dimensional state space
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作者 王成红 王昆 郑驻军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期180-184,共5页
We study the construction of mutually unbiased bases in Hilbert space for composite dimensions d which are not prime powers.We explore the results for composite dimensions which are true for prime power dimensions.We ... We study the construction of mutually unbiased bases in Hilbert space for composite dimensions d which are not prime powers.We explore the results for composite dimensions which are true for prime power dimensions.We then provide a method for selecting mutually unbiased vectors from the eigenvectors of generalized Pauli matrices to construct mutually unbiased bases.In particular,we present four mutually unbiased bases in C^(15). 展开更多
关键词 mutually unbiased bases Hilbert space Pauli matrix quantum measurement
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Low-dimensional multi-spectral space for color reproduction based on nonnegative constrained principal component analysis 被引量:1
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作者 王莹 曾平 +1 位作者 罗雪梅 谢琨 《Journal of Southeast University(English Edition)》 EI CAS 2009年第4期486-490,共5页
In order to overcome the shortcomings that the reconstructed spectral reflectance may be negative when using the classic principal component analysis (PCA)to reduce the dimensions of the multi-spectral data, a nonne... In order to overcome the shortcomings that the reconstructed spectral reflectance may be negative when using the classic principal component analysis (PCA)to reduce the dimensions of the multi-spectral data, a nonnegative constrained principal component analysis method is proposed to construct a low-dimensional multi-spectral space and accomplish the conversion between the new constructed space and the multispectral space. First, the reason behind the negative data is analyzed and a nonnegative constraint is imposed on the classic PCA. Then a set of nonnegative linear independence weight vectors of principal components is obtained, by which a lowdimensional space is constructed. Finally, a nonlinear optimization technique is used to determine the projection vectors of the high-dimensional multi-spectral data in the constructed space. Experimental results show that the proposed method can keep the reconstructed spectral data in [ 0, 1 ]. The precision of the space created by the proposed method is equivalent to or even higher than that by the PCA. 展开更多
关键词 spectral color science nonnegative constrained principal component analysis low-dimensional spectral space nonlinear optimization multi-spectral images spectral reflectance
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Three-dimensional Spaces of Quasi-constant Curvature
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作者 蒋声 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期32-35,共4页
In this paper some properties of three-dimensional spaces of quasi-constant curvature different from those of cases when dimension n≥4 are proved. In particular, two classes of non-conformally flat solutions of them ... In this paper some properties of three-dimensional spaces of quasi-constant curvature different from those of cases when dimension n≥4 are proved. In particular, two classes of non-conformally flat solutions of them are constructed. In physics,a three-dimensional space of quasi-constant curvature appears as the space-like hypersurface of the rotation-free cosmological model of type D for the fluids with heat flow in General Relativity. 展开更多
关键词 spaces of quasi-constant curvature non-conformally flat METRIC
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Generalizations of Euler Inequality in the n-dimensional Euclidean Space 被引量:4
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作者 WANG Wen YANG Shi-guo 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第2期218-223,共6页
The relation between the circum-radius and the in-radius of an n-dimensional simplex in E^n is studied.Two new generalizations of Euler inequality for the n-dimensional simplex are established.Besides,we obtain some s... The relation between the circum-radius and the in-radius of an n-dimensional simplex in E^n is studied.Two new generalizations of Euler inequality for the n-dimensional simplex are established.Besides,we obtain some stronger generalizations of Euler inequality for the n-dimensional simplex than previously known results. 展开更多
关键词 Euclidean space SIMPLEX circum-radius in-radius altitude Euler inequality
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THREE-DIMENSIONAL INTERACTIONS OF A HALF-PLANE CRACK IN A TRANSVERSELY ISOTROPIC PIEZOELECTRIC SPACE WITH RESULTANT SOURCES 被引量:3
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作者 Hou Pengfei Pan Xiaoping Ding Haojiang 《Acta Mechanica Solida Sinica》 SCIE EI 2005年第3期265-271,共7页
Exact solutions in elementary functions are derived for the stress and electric displacement intensity factors of a half-plane crack in a transversely isotropic piezoelectric space interacting with various resultant s... Exact solutions in elementary functions are derived for the stress and electric displacement intensity factors of a half-plane crack in a transversely isotropic piezoelectric space interacting with various resultant sources, including force dipole, electric dipole, moment, force dilatation and rotation. Such force and charge sources may model defects like vacancies, foreign particles and dislocations. The locations and orientations of the stress and charge sources with respect to the crack are arbitrary. 展开更多
关键词 half-plane crack piezoelectric space intensity factor resultant source
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MATCHING PURSUITS AMONG SHIFTED CAUCHY KERNELS IN HIGHER-DIMENSIONAL SPACES 被引量:2
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作者 钱涛 王晋勋 杨燕 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期660-672,共13页
Appealing to the Clifford analysis and matching pursuits, we study the adaptive decompositions of functions of several variables of finite energy under the dictionaries consisting of shifted Cauchy kernels. This is a ... Appealing to the Clifford analysis and matching pursuits, we study the adaptive decompositions of functions of several variables of finite energy under the dictionaries consisting of shifted Cauchy kernels. This is a realization of matching pursuits among shifted Cauchy kernels in higher-dimensional spaces. It offers a method to process signals in arbitrary dimensions. 展开更多
关键词 Hardy space MONOGENIC adaptive decomposition DICTIONARY matching pursuit optimal approximation by rational functions
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Risk Assessment of Coal Mine Water Hazard Based on Three-Dimensional Model of Geology and Underground Space 被引量:1
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作者 Kai Zhang~1,Ming Huang~1,Bin Tang~2,Fan Cui~1 1.Laboratory of Coal Resources and Mine Safety,China University of Mining and Technology,Beijing 100083,China. 2.China Water Investment Co.Ltd,Beijing 100053,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期279-279,共1页
Mine safety have top-five disasters,which including the water,gas,fire,dust and geological dynamic disaster.The coal mine water disaster is one of the important factors which restricted the development of China’s coa... Mine safety have top-five disasters,which including the water,gas,fire,dust and geological dynamic disaster.The coal mine water disaster is one of the important factors which restricted the development of China’s coal production.It is showed by statistics that 60%of mine accidents are affected by groundwater,which not only result in the production losses,casualties and a variety of 展开更多
关键词 DISASTER risk assessment THREE-dimensional model of GEOLOGY and UNDERGROUND space emergency RESCUE
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Localized wave solutions and interactions of the (2+1)-dimensional Hirota-Satsuma-Ito equation
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作者 巩乾坤 王惠 王云虎 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期409-416,共8页
This paper studies the(2+1)-dimensional Hirota-Satsuma-Ito equation.Based on an associated Hirota bilinear form,lump-type solution,two types of interaction solutions,and breather wave solution of the(2+1)-dimensional ... This paper studies the(2+1)-dimensional Hirota-Satsuma-Ito equation.Based on an associated Hirota bilinear form,lump-type solution,two types of interaction solutions,and breather wave solution of the(2+1)-dimensional Hirota-Satsuma-Ito equation are obtained,which are all related to the seed solution of the equation.It is interesting that the rogue wave is aroused by the interaction between one-lump soliton and a pair of resonance stripe solitons,and the fusion and fission phenomena are also found in the interaction between lump solitons and one-stripe soliton.Furthermore,the breather wave solution is also obtained by reducing the two-soliton solutions.The trajectory and period of the one-order breather wave are analyzed.The corresponding dynamical characteristics are demonstrated by the graphs. 展开更多
关键词 lump solution rogue wave solution breather wave solution (2+1)-dimensional Hirota-Satsuma-Ito equation
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THREE-DIMENSIONAL INTERACTIONS OF CIRCULAR CRACK IN TRANSVERSELY ISOTROPIC PIEZOELECTRIC SPACE WITH RESULTANT SOURCES 被引量:1
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作者 侯鹏飞 丁皓江 梁以德 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第11期1439-1449,共11页
Exact solutions in form of elementary functions were derived for the stress and electric displacement intensity factors of a circular crack in a transversely isotropic piezoelectric space interacting with various stre... Exact solutions in form of elementary functions were derived for the stress and electric displacement intensity factors of a circular crack in a transversely isotropic piezoelectric space interacting with various stress and charge sources: force dipoles, electric dipoles, moments, force dilatation and rotation. The circular crack includes penny-shaped crack and external circular crack and the locations and orientations of these resultant sources with respect to the crack are arbitrary. Such stress and charge sources may model defects like vacancies, foreign particles, and dislocations. Numerical results are presented at last. 展开更多
关键词 piezoelectric space circular crack resultant source intensity factor
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Continuous imaging space in three-dimensional integral imaging 被引量:1
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作者 张雷 杨勇 +3 位作者 王金刚 赵星 方志良 袁小聪 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第5期303-305,共3页
We report an integral imaging method with continuous imaging space. This method simultaneously reconstructs real and virtual images in the virtual mode, with a minimum gap that separates the entire imaging space into ... We report an integral imaging method with continuous imaging space. This method simultaneously reconstructs real and virtual images in the virtual mode, with a minimum gap that separates the entire imaging space into real and virtual space. Experimental results show that the gap is reduced to 45% of that in a conventional integral imaging system with the same parameters. 展开更多
关键词 three-dimensional integral imaging imaging space
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Abundant invariant solutions of extended(3+1)-dimensional KP-Boussinesq equation
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作者 Hengchun Hu Jiali Kang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期167-174,共8页
Lie group analysis method is applied to the extended(3+1)-dimensional Kadomtsev–Petviashvili–Boussinesq equation and the corresponding similarity reduction equations are obtained with various infinitesimal generator... Lie group analysis method is applied to the extended(3+1)-dimensional Kadomtsev–Petviashvili–Boussinesq equation and the corresponding similarity reduction equations are obtained with various infinitesimal generators.By selecting suitable arbitrary functions in the similarity reduction solutions,we obtain abundant invariant solutions,including the trigonometric solution,the kink-lump interaction solution,the interaction solution between lump wave and triangular periodic wave,the two-kink solution,the lump solution,the interaction between a lump and two-kink and the periodic lump solution in different planes.These exact solutions are also given graphically to show the detailed structures of this high dimensional integrable system. 展开更多
关键词 extended(3+1)-dimensional KP-Boussinesq equation Lie group method similarity reduction invariant solution
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Three-dimensionally ordered macroporous cross-linked polystyrene incorporating functional group via hydrophilic spacer arm 被引量:1
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作者 Li Xia Yuan Xiao Mei Wang Xu Zhang Pan Ge Liu Wei Dong Yan 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第12期1493-1496,共4页
A versatile and effective method for incorporating functional groups on the pore wall of three-dimensionally ordered macroporous cross-linked polystyrene(3DOM CLPS) by hydrophilic spacer arm has been investigated.Th... A versatile and effective method for incorporating functional groups on the pore wall of three-dimensionally ordered macroporous cross-linked polystyrene(3DOM CLPS) by hydrophilic spacer arm has been investigated.The 3DOM CLPS with pore size 865 nm was prepared by sacrifice template method.The hydrophilic spacer arm(polyethylene glycol,molecular weight is 600) was grafted to the 3DOM CLPS via nucleophilic substitution reaction.The other side of active hydroxyl can be further converted into a lot of other functional groups.In this report,the chelating ligand 2-mercaptobenzothiazole(MBZ) group was introduced on the end of the PGE chain to evidence the versatile functionalization approach.The functionalized ordered macroporous materials were characterized by FT-IR,element analyzer,SEM.The results reveal that the pores were successfully bonded with 2-mercaptobenzothiazole groups via hydrophilic spacer arms and the original morphology of ordered macroporous materials were remained after functionalization.The MBZ group density is 0.052 mmol/m^2.The functionalized 3DOM CLPS are expected to application as heavy metal ions adsorbent. 展开更多
关键词 Three-dimensionally ordered macroporous polymer FUNCTIONALIZATION Hydrophilic space arm Heterocyclic functional group
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Volume of unit ball in an n-dimensional normed space and its asymptotic properties 被引量:3
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作者 黄智悦 何斌吾 《Journal of Shanghai University(English Edition)》 CAS 2008年第2期107-109,共3页
Let Bp^n={x∈R^b|‖x‖p≤1} be the unit ball of p norm in the n-dimensional normed space εp&n.The formula for the volume of Bp^n was obtained and its asymptotic properties were found out as n→∞and p→∞.
关键词 unit ball normed space VOLUMES gamma function asymptotic properties.
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Dynamics of Nonlinear Waves in(2+1)-Dimensional Extended Boiti-Leon-Manna-Pempinelli Equation
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作者 SUN Junxiu WANG Yunhu 《应用数学》 北大核心 2024年第4期1103-1113,共11页
Based on the Hirota bilinear method,this study derived N-soliton solutions,breather solutions,lump solutions and interaction solutions for the(2+1)-dimensional extended Boiti-Leon-Manna-Pempinelli equation.The dynamic... Based on the Hirota bilinear method,this study derived N-soliton solutions,breather solutions,lump solutions and interaction solutions for the(2+1)-dimensional extended Boiti-Leon-Manna-Pempinelli equation.The dynamical characteristics of these solutions were displayed through graphical,particularly revealing fusion and ssion phenomena in the interaction of lump and the one-stripe soliton. 展开更多
关键词 Hirota bilinear method N-soliton solutions Breather solutions Lump solutions Interaction solutions (2+1)-dimensional extended Boiti-Leon-Manna-Pempinelli equation
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Hyper Catastrophe on 4-Dimensional Canards
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作者 Kiyoyuki Tchizawa Shuya Kanagawa 《Advances in Pure Mathematics》 2024年第4期196-203,共8页
When discovering the potential of canards flying in 4-dimensional slow-fast system with a bifurcation parameter, the key notion “symmetry” plays an important role. It is of one parameter on slow vector field. Then, ... When discovering the potential of canards flying in 4-dimensional slow-fast system with a bifurcation parameter, the key notion “symmetry” plays an important role. It is of one parameter on slow vector field. Then, it should be determined to introduce parameters to all slow/fast vectors. It is, however, there might be no way to explore for another potential in this system, because the geometrical structure is quite different from the system with one parameter. Even in this system, the “symmetry” is also useful to obtain the potentials classified by R. Thom. In this paper, via the coordinates changing, the possible way to explore for the potential will be shown. As it is analyzed on “hyper finite time line”, or done by using “non-standard analysis”, it is called “Hyper Catastrophe”. In the slow-fast system which includes a very small parameter , it is difficult to do precise analysis. Thus, it is useful to get the orbits as a singular limit. When trying to do simulations, it is also faced with difficulty due to singularity. Using very small time intervals corresponding small , we shall overcome the difficulty, because the difference equation on the small time interval adopts the standard differential equation. These small intervals are defined on hyper finite number N, which is nonstandard. As and the intervals are linked to use 1/N, the simulation should be done exactly. 展开更多
关键词 Canards Flying 4-dimensional Slow-Fast System Hyper Catastrophe
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Multiverse/Hyperverse Models: (4 + 1)-Dimensional Landscape (Black Saturns, Bousso-Hawking Nucleation, Gogberashvili Multiverses, Schwarzschild-De Sitter Nurseries) and a (3 + 1)-Dimensional Model for Dark Energy
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作者 Igor Yu. Potemine Werner Krause 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1866-1877,共12页
We consider the Hyperverse as a collection of multiverses in a (4 + 1)-dimensional spacetime with gravitational constant G. Multiverses in our model are bouquets of thin shells (with synchronized intrinsic times). If ... We consider the Hyperverse as a collection of multiverses in a (4 + 1)-dimensional spacetime with gravitational constant G. Multiverses in our model are bouquets of thin shells (with synchronized intrinsic times). If gis the gravitational constant of a shell Sand εits thickness, then G~εg. The physical universe is supposed to be one of those thin shells inside the local bouquet called Local Multiverse. Other remarkable objects of the Hyperverse are supposed to be black holes, black lenses, black rings and (generalized) Black Saturns. In addition, Schwarzschild-de Sitter multiversal nurseries can be hidden inside those Black Saturns, leading to their Bousso-Hawking nucleation. It also suggests that black holes in our physical universe might harbor embedded (2 + 1)-dimensional multiverses. This is compatible with outstanding ideas and results of Bekenstein, Hawking-Vaz and Corda about “black holes as atoms” and the condensation of matter on “apparent horizons”. It allows us to formulate conjecture 12.1 about the origin of the Local Multiverse. As an alternative model, we examine spacetime warping of our universe by external universes. It gives data for the accelerated expansion and the cosmological constant Λ, which are in agreement with observation, thus opening a possibility for verification of the multiverse model. 展开更多
关键词 5-dimensional Gravity Black Hole Black Saturn Cosmological Constant Dark Energy MULTIVERSE spacetime Warping Thin Shell
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Fast Two-dimensional Positioning Method of Crab Pulsar Based on Multiple Optimization Algorithms
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作者 Jianfeng Chen Jin Liu +1 位作者 Xin Ma Xiaolin Ning 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第10期92-103,共12页
In the two-dimensional positioning method of pulsars, the grid method is used to provide non-sensitive direction and positional estimates. However, the grid method has a high computational load and low accuracy due to... In the two-dimensional positioning method of pulsars, the grid method is used to provide non-sensitive direction and positional estimates. However, the grid method has a high computational load and low accuracy due to the interval of the grid. To improve estimation accuracy and reduce the computational load, we propose a fast twodimensional positioning method for the crab pulsar based on multiple optimization algorithms(FTPCO). The FTPCO uses the Levenberg–Marquardt(LM) algorithm, three-point orientation(TPO) method, particle swarm optimization(PSO) and Newton–Raphson-based optimizer(NRBO) to substitute the grid method. First, to avoid the influence of the non-sensitive direction on positioning, we take an orbital error and the distortion of the pulsar profile as optimization objectives and combine the grid method with the LM algorithm or PSO to search for the non-sensitive direction. Then, on the sensitive plane perpendicular to the non-sensitive direction, the TPO method is proposed to fast search the sensitive direction and sub-sensitive direction. Finally, the NRBO is employed on the sensitive and sub-sensitive directions to achieve two-dimensional positioning of the Crab pulsar. The simulation results show that the computational load of the FTPCO is reduced by 89.4% and the positioning accuracy of the FTPCO is improved by approximately 38% compared with the grid method. The FTPCO has the advantage of high real-time accuracy and does not fall into the local optimum. 展开更多
关键词 (stars:)pulsars:individual(Crab pulsar) space vehicles methods:data analysis ASTROMETRY
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An iterated local coordinate-exchange algorithm for constructing experimental designs for multi-dimensional constrained spaces 被引量:1
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作者 YOU Yang JIN Guang +1 位作者 PAN Zhengqiang GUO Rui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第5期1212-1220,共9页
Iterated local search(ILS)is used to construct the optimal experimental designs for multi-dimensional constrained spaces,in which the inner loop is based on the stochastic coordinate-exchange(SCE)algorithm.Every time ... Iterated local search(ILS)is used to construct the optimal experimental designs for multi-dimensional constrained spaces,in which the inner loop is based on the stochastic coordinate-exchange(SCE)algorithm.Every time a local optimal solution is found by the SCE algorithm,the perturbation operator is applied to it,and then a new solution is explored in the areas where the exchange of coordinates may produce improvement,so as to retain the features and attributes of the current optimal solution and avoid the defects of random restart.We implement the iterated local coordinate-exchange algorithm for experimental designs in the multi-dimensional constrained spaces.In addition,sensitivity analysis was conducted to analyze the impacts of the parameters on the performance of the proposed algorithm.Also we compared the performance of the proposed algorithm to the SCE algorithm using the random restart strategy.The analysis shows that the proposed algorithm is better than the SCE algorithm in terms of efficiency and quality,especially in the experimental designs for high-dimensional constrained space. 展开更多
关键词 constrained space experimental design coordinate-exchange iterated local search(ILS)
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Using"Three-dimensional Space Resources"for Fenlong Technology to Improve Grain Econoloy and Expand Human Living Spaces 被引量:1
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作者 Benhui WEI 《Asian Agricultural Research》 2020年第12期32-38,共7页
Fenlong Technology has been applied to increase yield by 20%-50%,improve quality by 5%,and retain water by 100%in 40 kinds of crop cultivated land and saline-alkali land in 26 provinces of China.This paper clarified f... Fenlong Technology has been applied to increase yield by 20%-50%,improve quality by 5%,and retain water by 100%in 40 kinds of crop cultivated land and saline-alkali land in 26 provinces of China.This paper clarified for the first time the scientific theory system of Fenlong Technology using three-dimensional space resources"Fenlong Agricultural Nature Theory"and the development of the relative"limits"of agricultural growth,which provides a huge power support and natural force for expanding human living spaces.Through inventing and creating a scientific and technological system of farming tools,farming machinery,farming modes,and magic weapons for cultivation,Fenlong Technology can increase grain,promote ecological development,and greatly expand the living spaces of the Chinese nation and achieve sustainable development.Using Fenlong Technology,China has expanded from the current single"cultivated land agriculture"to the"big pattern agriculture"of Fenlong"cultivated land+saline land+degraded grassland+marginal land+desertified land+river water",flexibly used 147 million ha of"three-dimensional space resources"of land,and the newly increased food,meat,and fish can feed 300 million to 400 million people,increased the water storage by 100 billion m^(3),and reduced the collection of groundwater by 20 million to 60 billion m^(3). 展开更多
关键词 Three-dimensional space resources Fenlong Agricultural Nature Theory Relative"limits" Expanding the living spaces Improving the grain ecology Fenlong farming
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Bifurcations, Analytical and Non-Analytical Traveling Wave Solutions of (2 + 1)-Dimensional Nonlinear Dispersive Boussinesq Equation
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作者 Dahe Feng Jibin Li Airen Zhou 《Applied Mathematics》 2024年第8期543-567,共25页
For the (2 + 1)-dimensional nonlinear dispersive Boussinesq equation, by using the bifurcation theory of planar dynamical systems to study its corresponding traveling wave system, the bifurcations and phase portraits ... For the (2 + 1)-dimensional nonlinear dispersive Boussinesq equation, by using the bifurcation theory of planar dynamical systems to study its corresponding traveling wave system, the bifurcations and phase portraits of the regular system are obtained. Under different parametric conditions, various sufficient conditions to guarantee the existence of analytical and non-analytical solutions of the singular system are given by using singular traveling wave theory. For certain special cases, some explicit and exact parametric representations of traveling wave solutions are derived such as analytical periodic waves and non-analytical periodic cusp waves. Further, two-dimensional wave plots of analytical periodic solutions and non-analytical periodic cusp wave solutions are drawn to visualize the dynamics of the equation. 展开更多
关键词 (2 + 1)-dimensional Nonlinear Dispersive Boussinesq Equation BIFURCATIONS Phase Portrait Analytical Periodic Wave Solution Periodic Cusp Wave Solution
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