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A study of making use of computer-aided projection fringe system to measure breast dimension
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作者 查选平 《外科研究与新技术》 2005年第3期211-211,共1页
To measure breast basic dimension by using computer-aided projection fringe system.Methods A system has been developed for measuring breast basic dimension based on computer-aided projection fringe measurement and pro... To measure breast basic dimension by using computer-aided projection fringe system.Methods A system has been developed for measuring breast basic dimension based on computer-aided projection fringe measurement and programming software.Plastic manikins breast’s SN-N (sternal notch to nipple distance),N-ML (nipple to midline distance),N-N (internipple distance),MBW (base width of breast) and N-IMF (nipple to inframammary fold distance) are measured with this system.At the same time,these items are also measured with routine ruler.Results This study indicate that the system has some merits:① non-touching measurement;② it is very rapid,the patient measured need hold his breath only 0.5 second,and all the time it takes is about 2.5 minutes;③ the measurement’s sensitivity is as high as to 0.6 mm,which meets the clinic requirement entirely;④ the measurement’s accuracy of the system is not significantly when comparing to the routine ruler’s.Conclusion Computer-adided projection fringe system for measuring breast basic dimension is feasible and advanced.14 refs,1 fig. 展开更多
关键词 A study of making use of computer-aided projection fringe system to measure breast dimension
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On Ding homological dimensions 被引量:1
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作者 ZHU Hai-yan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2015年第4期491-502,共12页
In this paper, we investigate Ding projective dimensions and Ding injective di- mensions of modules and rings. Let R be a ring with rDPD(R) = n 〈 ∞, and let YYl = {Mild(M) 〈 ∞}. We prove that (DP,W1) is a co... In this paper, we investigate Ding projective dimensions and Ding injective di- mensions of modules and rings. Let R be a ring with rDPD(R) = n 〈 ∞, and let YYl = {Mild(M) 〈 ∞}. We prove that (DP,W1) is a complete hereditary cotorsion pair such that a module M belongs to DD∩W1 if and only if M is projective, moreover, 1421 = (M[pd(M) 〈 ∞} = {MIfd(M) ≤ n} = {MIpd(M) ≤ n}. Then we introduce and inves- tigate Ding derived functor Dext^i(-, -), and use it to characterize global Ding dimension. We show that if R is a Ding-Chen ring, or if R is a ring with rDPD(R) 〈≤ and rDID(R) 〈 ≤, then rDPD(R) 〈 n if and only if rDID(R) 〈 n if and only if Dext^n+i(M,N) = 0 for all modules M and N and all integer i ≥ 1. 展开更多
关键词 Ding projective (injective) dimension cotorsion pair derived functor.
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Inverse full state hybrid projective synchronization for chaotic maps with different dimensions 被引量:3
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作者 Adel Ouannas Giuseppe Grassi 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期251-256,共6页
A new synchronization scheme for chaotic(hyperchaotic) maps with different dimensions is presented.Specifically,given a drive system map with dimension n and a response system with dimension m,the proposed approach ... A new synchronization scheme for chaotic(hyperchaotic) maps with different dimensions is presented.Specifically,given a drive system map with dimension n and a response system with dimension m,the proposed approach enables each drive system state to be synchronized with a linear response combination of the response system states.The method,based on the Lyapunov stability theory and the pole placement technique,presents some useful features:(i) it enables synchronization to be achieved for both cases of n 〈 m and n 〉 m;(ii) it is rigorous,being based on theorems;(iii) it can be readily applied to any chaotic(hyperchaotic) maps defined to date.Finally,the capability of the approach is illustrated by synchronization examples between the two-dimensional H′enon map(as the drive system) and the three-dimensional hyperchaotic Wang map(as the response system),and the three-dimensional H′enon-like map(as the drive system) and the two-dimensional Lorenz discrete-time system(as the response system). 展开更多
关键词 chaotic map full state hybrid projective synchronization inverse problem maps with different dimensions
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On Rings with Finite Global Gorenstein Dimensions
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作者 REN Wei ZHANG Yu 《Chinese Quarterly Journal of Mathematics》 2017年第3期255-260,共6页
As a proper setting to study Gorenstein projective and injective dimensions of modules via vanishing of Gorenstein Ext-functors, a notion of a generalized Gorenstein ring is introduced, which is a non-trivial generali... As a proper setting to study Gorenstein projective and injective dimensions of modules via vanishing of Gorenstein Ext-functors, a notion of a generalized Gorenstein ring is introduced, which is a non-trivial generalization of Gorenstein rings. Moreover, a new proof for Bennis and Mahdou's equality of global Gorenstein dimension is given. 展开更多
关键词 generalized Gorenstein ring Gorenstein projective(injective) dimension
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Relative Ding Projective Modules over Formal Triangular Matrix Rings
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作者 Hongyan Fan Xi Tang 《Journal of Applied Mathematics and Physics》 2023年第6期1598-1614,共17页
Let U be a (B, A)-bimodule, A and B be rings, and be a formal triangular matrix ring. In this paper, we characterize the structure of relative Ding projective modules over T under some conditions. Furthermore, using t... Let U be a (B, A)-bimodule, A and B be rings, and be a formal triangular matrix ring. In this paper, we characterize the structure of relative Ding projective modules over T under some conditions. Furthermore, using the left global relative Ding projective dimensions of A and B, we estimate the relative Ding projective dimension of a left T-module. 展开更多
关键词 Formal Triangular Matrix Ring Relative Ding Projective Module Relative Ding Projective dimension
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A Creation Model from the Gell-Mann Standard Model to the Creation of Bio Cells: Based on the Assumption of Homogeneous 5D Space-Time Universe
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作者 Kai Wai Wong Wan Ki Chow 《Journal of Modern Physics》 2020年第7期1058-1074,共17页
In this paper, we briefly go over the homogeneous 5D model field theory: from the 5D space-time inception, to its quantum field solutions given in terms of Higgs vacuum, filled with magnetic monopole bose fields of al... In this paper, we briefly go over the homogeneous 5D model field theory: from the 5D space-time inception, to its quantum field solutions given in terms of Higgs vacuum, filled with magnetic monopole bose fields of all energies. Then through the space dimension reduction projections, the Gell-Mann standard model was obtained as well as a quantum to Classical connection was made via introducing Bose distribution to the monopoles to obtain the Perelman entropy and Ricci Flow mappings. This provided us a picture to the creation of Astronomical objects, from galaxies to stars and planets. This method of splitting the monopole energy into ranges is extended to show that below the basic rest mass range of the electron and Quark, it still can be applied to explaining for the creation of the chemical elements periodic table. But perhaps the most interesting is in the lowest hundreds of Hz energy range, obtained from yet another 3 fold space symmetry breaking, into 2D × 1D, producing bio nitrogenous bases composed of 3 Carbon 12 in hexagon structures, due to preservation of the 1D monopole standing waves of this low frequencies. From that by imposing gauge changes the monopole states into DNA spectra. Since such spectra states retain the DLRO, it induces formation of charge carriers periodicity in a spherical bio cell.. It was then argued that due to cell’s surface proteins, the structure must contain partial filled VB, with “p” state hole density, and empty CB, separated from VB by a positive band gap. Such band structures resemble known HTC Cuprate ceramics. Since the HTC goes through a Superconductivity transition via the simultaneous bose exciton condensation, providing a Coulomb pressure, which reduces the band gap substantially, and induces the ODLRO transition of the hole density. The same obviously applies to the bio cells. Because of the near continuous exciton levels generated, a matching to the DNA spectra then can always occur by selective choices of proteins on the cell surface. Judging from a numerical study, we did years ago on YBCO, with doping. We found with a large enough VB hole density, the exciton induced superconducting gap can easily lead to <em>T</em><em>c</em> in the room temperature range. In fact by EMF excitation can increase the exciton pressure and trigger the ODLRO transition <em>T</em><em>c</em> upward. In fact, numerical results then suggest there do exist coherent EMF spectra from three key elements: Water, Carbon and Hydrogen, together with Oxygen, as studied over the years by numerous people, starting from Schr<span style="white-space:nowrap;">&ouml;</span>dinger to most recently Geesink. 展开更多
关键词 5D Fermat’s Theorem Space dimension Reduction projections Perelman Mappings The Higgs Vacuum: A B.E. Condensed Monopole Bosons Realization of Excitonic Induced Superconducting “p” Valence Band Orbitals in Bio Cells The Final Coherent Building Block EMF Spectra: Water Carbon Hydrogen and Oxygen
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Gorenstein Projective Dimensions of Complexes 被引量:7
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作者 Zhong Kui LIU Chun Xia ZHANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2011年第7期1395-1404,共10页
We show that over a right coherent left perfect ring R, a complex C of left R-modules is Gorenstein projective if and only if C^m is Gorenstein projective in R-Mod for all m E Z. Basing on this we show that if R is a ... We show that over a right coherent left perfect ring R, a complex C of left R-modules is Gorenstein projective if and only if C^m is Gorenstein projective in R-Mod for all m E Z. Basing on this we show that if R is a right coherent left perfect ring then Gpd(C) = sup{Gpd(C^m)|m ∈ Z} where Gpd(-) denotes Gorenstein projective dimension. 展开更多
关键词 Gorenstein projective complex Gorenstein projective module Gorenstein projective dimension projective preenvelope
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On Gorenstein Projective Dimensions of Unbounded Complexes
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作者 Zhongkui LIU Zhanping WANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2020年第5期761-772,共12页
Let R→S be a ring homomorphism and X be a complex of R-modules.Then the complex of S-modules S L RX in the derived category D(S)is constructed in the natural way.This paper is devoted to dealing with the relationship... Let R→S be a ring homomorphism and X be a complex of R-modules.Then the complex of S-modules S L RX in the derived category D(S)is constructed in the natural way.This paper is devoted to dealing with the relationships of the Gorenstein projective dimension of an R-complex X(possibly unbounded)with those of the S-complex S■R^L X.It is shown that if R is a Noetherian ring of finite Krull dimension and:R→S is a faithfully flat ring homomorphism,then for any homologically degree-wise finite complex X,there is an equality GpdRX=GpdS(S■R^LX).Similar result is obtained for Ding projective dimension of the S-complex S■R^L X. 展开更多
关键词 Gorenstein projective dimension Ding projective dimension Faithfully flat ring homomorphism
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Castelnuovo-Mumford regularity and projective dimension of a squarefree monomial ideal
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作者 Lizhong CHU Shisen LIU Zhongming TANG 《Frontiers of Mathematics in China》 SCIE CSCD 2018年第2期277-286,共10页
Let S = K[x1, x2,..., xn] be the polynomial ring in n variables over a field K, and let I be a squarefree monomial ideal minimally generated by the monomials ul,u2,...,Um. Let w be the smallest number t with the prope... Let S = K[x1, x2,..., xn] be the polynomial ring in n variables over a field K, and let I be a squarefree monomial ideal minimally generated by the monomials ul,u2,...,Um. Let w be the smallest number t with the property that for all integers 1 ≤ i1 〈 i2 〈 … 〈 it ≤ m such that lcm(uil, ui2,..., uii) = lcm(ul,u2,...,Um). We give an upper bound for Castelnuovo-Mumford regularity of I by the bigsize of I. As a corollary, the projective dimension of I is bounded by the number w. 展开更多
关键词 Castelnuovo-Mumford regularity projective dimension squarefree monomial ideals
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Gorenstein Projective Dimensions of Modules over Minimal Auslander-Gorenstein Algebras
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作者 Shen Li René Marczinzik Shunhua Zhang 《Algebra Colloquium》 SCIE CSCD 2021年第2期337-350,共14页
In this article we investigate the relations between the Gorenstein projective dimensions of Λ-modules and their socles for re-minimal Auslander-Gorenstein algebras Λ.First we give a description of projective-inject... In this article we investigate the relations between the Gorenstein projective dimensions of Λ-modules and their socles for re-minimal Auslander-Gorenstein algebras Λ.First we give a description of projective-injective Λ-modules in terms of their socles.Then we prove that a Λ-module N has Gorenstein projective dimension at most n if and only if its socle has Gorenstein projective dimension at most n if and only if N is cogenerated by a projective Λ-module.Furthermore,we show that n-minimal Auslander-Gorenstein algebras can be characterised by the relations between the Gorenstein projective dimensions of modules and their socles. 展开更多
关键词 Gorenstein projective dimension minimal Auslander-Gorenstein algebra higher Auslander algebra
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Gorenstein Projective Coresolutions and Co-Tate Homology Functors
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作者 Zhongkui Liu Li Wang 《Algebra Colloquium》 SCIE CSCD 2023年第1期1-14,共14页
For a local commutative Gorenstein ring R,Enochs et al.in[Gorenstein projective resolvents,Comm.Algebra 44(2016)3989-4000)defined a functor Extn^(R)(-,-)and showed that this functor can be computed by taking a totally... For a local commutative Gorenstein ring R,Enochs et al.in[Gorenstein projective resolvents,Comm.Algebra 44(2016)3989-4000)defined a functor Extn^(R)(-,-)and showed that this functor can be computed by taking a totally acyclic complex arising from a projective coresolution of the first component or a totally acyclic complex arising from a projective resolution of the second component.In order to define the functor Extn^(R)(-,-)over general rings,we introduce the right Gorenstein projective dimension of an R-module M,RGpd(M),via Gorenstein projective coresolutions,and give some equivalent characterizations for the finiteness of RGpd(M).Then over a general ring R we define a co-Tate homology group Extn^(R)(-,-) for R-modules M and N with RGpd(M)<oo and Gpd(N)<∞,and prove that Extn^(R)(M,N)can be computed by complete projective coresolutions of the first variable or by complete projective resolutions of the second variable. 展开更多
关键词 Gorenstein projective preenvelope Gorenstein projective coresolution right Gorenstein projective dimension co-Tate homology functor
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Algebraic Properties of Edge Ideals of Some Vertex-Weighted Oriented Cyclic Graphs 被引量:1
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作者 Hong Wang Guangjun Zhu +2 位作者 Li Xu Jiaqi Zhang Zhongming Tang 《Algebra Colloquium》 SCIE CSCD 2021年第2期253-268,共16页
We provide some exact formulas for the projective dimension and regularity of edge ideals associated to some vertex-weighted oriented cyclic graphs with a common vertex or edge.These formulas axe functions in the weig... We provide some exact formulas for the projective dimension and regularity of edge ideals associated to some vertex-weighted oriented cyclic graphs with a common vertex or edge.These formulas axe functions in the weight of the vertices,and the numbers of edges and cycles.Some examples show that these formulas are related to direction selection and the assumption that w(x)≥2 for any vertex x cannot be dropped. 展开更多
关键词 projective dimension REGULARITY edge ideal cyclic graph with a common vertex cyclic graph with a common edge
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Complete Cohomology for Extriangulated Categories
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作者 Jiangsheng Hu Dongdong Zhang +1 位作者 Tiwei Zhao Panyue Zhou 《Algebra Colloquium》 SCIE CSCD 2021年第4期701-720,共20页
Let(C,E,s)be an extriangulated category with a proper classξof E-triangles.We study complete cohomology of objects in(C,E,s)by applyingξ-projective resolutions andξ-injective coresolutions constructed in(C,E,s).Van... Let(C,E,s)be an extriangulated category with a proper classξof E-triangles.We study complete cohomology of objects in(C,E,s)by applyingξ-projective resolutions andξ-injective coresolutions constructed in(C,E,s).Vanishing of complete cohomology detects objects with finiteξ-projective dimension and finiteξ-injective dimension.As a consequence,we obtain some criteria for the validity of the Wakamatsu tilting conjecture and give a necessary and sufficient condition for a virtually Gorenstein algebra to be Gorenstein.Moreover,we give a general technique for computing complete cohomology of objects with finiteξ-Gprojective dimension.As an application,the relations betweenξ-projective dimension andξ-Gprojective dimension for objects in(C,E,s)are given. 展开更多
关键词 complete cohomology extriangulated category proper class Gorenstein projective dimension
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Finiteness Conditions and Relative Singularity Categories
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作者 Chun Xia ZHANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2022年第8期1436-1446,共11页
We introduce the n-pure projective(resp.,injective)dimension of complexes in n-pure derived categories,and give some criteria for computing these dimensions in terms of the n-pure projective(resp.,injective)resolution... We introduce the n-pure projective(resp.,injective)dimension of complexes in n-pure derived categories,and give some criteria for computing these dimensions in terms of the n-pure projective(resp.,injective)resolutions(resp.,coresolutions)and n-pure derived functors.As a consequence,we get some equivalent characterizations for the finiteness of n-pure global dimension of rings.Finally,we study Verdier quotient of bounded n-pure derived category modulo the bounded homotopy category of n-pure projective modules,which is called an n-pure singularity category since it can reflect the finiteness of n-pure global dimension of rings. 展开更多
关键词 n-pure projective dimension n-pure injective dimension n-pure global dimension n-pure derived category n-pure singularity category
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