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Another Gorenstein Analogue of Projective Complexes
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作者 LU Bo LIU Yifu 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2020年第6期477-482,共6页
As we know,a complex P is projective if and only if P is exact with Z_n(P)projective in R-Mod for each n∈Z and any morphism f:P→C is null homotopic for any complex C.In this article,we study the notion of DG-Gorenst... As we know,a complex P is projective if and only if P is exact with Z_n(P)projective in R-Mod for each n∈Z and any morphism f:P→C is null homotopic for any complex C.In this article,we study the notion of DG-Gorenstein projective complexes.We show that a complex G is DG-Gorenstein projective if and only if G is exact with Z_n(G)Gorenstein projective in R-Mod for each n∈Z and any morphism f:G→Q is null homotopic whenever Q is a DG-projective complex. 展开更多
关键词 Gorenstein projective module DG-projective complex DG-Gorenstein projective complex
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Understanding Complexity at the Pre-Construction Stage of Project Planning for Construction Projects
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作者 Mehran Barani Shikhrobat Roger Flanagan Shabnam Kabiri 《American Journal of Operations Research》 2025年第1期1-27,共27页
The construction projects’ dynamic and interconnected nature requires a comprehensive understanding of complexity during pre-construction. Traditional tools such as Gantt charts, CPM, and PERT often overlook uncertai... The construction projects’ dynamic and interconnected nature requires a comprehensive understanding of complexity during pre-construction. Traditional tools such as Gantt charts, CPM, and PERT often overlook uncertainties. This study identifies 20 complexity factors through expert interviews and literature, categorising them into six groups. The Analytical Hierarchy Process evaluated the significance of different factors, establishing their corresponding weights to enhance adaptive project scheduling. A system dynamics (SD) model is developed and tested to evaluate the dynamic behaviour of identified complexity factors. The model simulates the impact of complexity on total project duration (TPD), revealing significant deviations from initial deterministic estimates. Data collection and analysis for reliability tests, including normality and Cronbach alpha, to validate the model’s components and expert feedback. Sensitivity analysis confirmed a positive relationship between complexity and project duration, with higher complexity levels resulting in increased TPD. This relationship highlights the inadequacy of static planning approaches and underscores the importance of addressing complexity dynamically. The study provides a framework for enhancing planning systems through system dynamics and recommends expanding the model to ensure broader applicability in diverse construction projects. 展开更多
关键词 Project Planning Project complexity Measurement Uncertainty Management Project Risk Management Strategic Project Scheduling
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Some remarks on pseudo-umbilical totally real submanifolds in a complex projective space 被引量:3
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作者 ZHANG Liang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第2期227-232,共6页
This paper studies the relationship between the pseudo-umbilical totally real submanifolds and the minimal totally real submanifolds in a complex projective space. Two theo- rems which claim that some types of pseudo-... This paper studies the relationship between the pseudo-umbilical totally real submanifolds and the minimal totally real submanifolds in a complex projective space. Two theo- rems which claim that some types of pseudo-umbilical totally real submanifolds must be minimal submanifolds are proved. 展开更多
关键词 complex projective space totally real submanifold pseudo-umbilical submanifold minimal submanifold.
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Finite-time complex projective synchronization of fractional-order complex-valued uncertain multi-link network and its image encryption application
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作者 Yong-Bing Hu Xiao-Min Yang +1 位作者 Da-Wei Ding Zong-Li Yang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第11期244-255,共12页
Multi-link networks are universal in the real world such as relationship networks,transportation networks,and communication networks.It is significant to investigate the synchronization of the network with multi-link.... Multi-link networks are universal in the real world such as relationship networks,transportation networks,and communication networks.It is significant to investigate the synchronization of the network with multi-link.In this paper,considering the complex network with uncertain parameters,new adaptive controller and update laws are proposed to ensure that complex-valued multilink network realizes finite-time complex projective synchronization(FTCPS).In addition,based on fractional-order Lyapunov functional method and finite-time stability theory,the criteria of FTCPS are derived and synchronization time is given which is associated with fractional order and control parameters.Meanwhile,numerical example is given to verify the validity of proposed finite-time complex projection strategy and analyze the relationship between synchronization time and fractional order and control parameters.Finally,the network is applied to image encryption,and the security analysis is carried out to verify the correctness of this method. 展开更多
关键词 multi-links network fractional order complex-valued network finite-time complex projective synchronization image encryption
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A Note on Totally Real Riemannian Foliations with Parallelized Mean Curvature Vectors in a Complex Projective Space
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作者 PENG Hui-chun 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第3期410-414,共5页
We discussed a totally real Riemannian foliations with parallel mean curvature on a complex projective space.We carried out the divergence of a vector field on it and obtained a formula of Simons’type.
关键词 Riemannian foliations complex projective space mean curvature DIVERGENCE
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2-Harmonic Totally Real Submanifolds in a Complex Projective Space
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作者 孙弘安 《Chinese Quarterly Journal of Mathematics》 CSCD 1995年第3期37-41,共5页
In this paper, we discuss the relations between the 2-harmornic totally real submsnifold and the minimal totall real submanifold in the complex protective spsace, and obtain the pinching conductions for the second fu... In this paper, we discuss the relations between the 2-harmornic totally real submsnifold and the minimal totall real submanifold in the complex protective spsace, and obtain the pinching conductions for the second fundamental form and the Rieci curature of the 2-harmornic totally real submanifold in the complex projective space. 展开更多
关键词 complex projective space totally real 2-HARMONIC MINIMAL
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Complex Modified Projective Synchronization for Fractional-order Chaotic Complex Systems
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作者 Cui-Mei Jiang Shu-Tang Liu Fang-Fang Zhang 《International Journal of Automation and computing》 EI CSCD 2018年第5期603-615,共13页
The aim of this paper is to study complex modified projective synchronization(CMPS) between fractional-order chaotic nonlinear systems with incommensurate orders. Based on the stability theory of incommensurate frac... The aim of this paper is to study complex modified projective synchronization(CMPS) between fractional-order chaotic nonlinear systems with incommensurate orders. Based on the stability theory of incommensurate fractional-order systems and active control method, control laws are derived to achieve CMPS in three situations including fractional-order complex Lorenz system driving fractional-order complex Chen system, fractional-order real Rssler system driving fractional-order complex Chen system, and fractionalorder complex Lorenz system driving fractional-order real Lü system. Numerical simulations confirm the validity and feasibility of the analytical method. 展开更多
关键词 Fractional-order system chaotic complex system incommensurate order complex modified projective synchronization(CMPS) active control.
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Modified projective synchronization with complex scaling factors of uncertain real chaos and complex chaos
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作者 张芳芳 刘树堂 余卫勇 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期141-151,共11页
To increase the variety and security of communication, we present the definitions of modified projective synchronization with complex scaling factors (CMPS) of real chaotic systems and complex chaotic systems, where... To increase the variety and security of communication, we present the definitions of modified projective synchronization with complex scaling factors (CMPS) of real chaotic systems and complex chaotic systems, where complex scaling factors establish a link between real chaos and complex chaos. Considering all situations of unknown parameters and pseudo-gradient condition, we design adaptive CMPS schemes based on the speed-gradient method for the real drive chaotic system and complex response chaotic system and for the complex drive chaotic system and the real response chaotic system, respectively. The convergence factors and dynamical control strength are added to regulate the convergence speed and increase robustness. Numerical simulations verify the feasibility and effectiveness of the presented schemes. 展开更多
关键词 modified projective synchronization complex scaling factors complex chaotic systems speed-gradient method
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Experimental self-testing of complex projective measurements via elegant Bell inequality
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作者 Xinhui Li Yingning Miao +7 位作者 Wei Zhou Xuhao Yu Wenhui Song Ying Wei Fei Gao Xiaoqin Gao Yan-Xiao Gong Shi-Ning Zhu 《Science China(Physics,Mechanics & Astronomy)》 2025年第9期113-121,共9页
Self-testing is a powerful tool that allows one to verify the security of quantum systems without relying on the characterized devices.However,conventional self-testing protocols are fundamentally restricted to real-s... Self-testing is a powerful tool that allows one to verify the security of quantum systems without relying on the characterized devices.However,conventional self-testing protocols are fundamentally restricted to real-space measurements,significantly constraining their applicability.In this work,we present an innovative protocol for self-testing projective measurements in complex Hilbert space through an elegant Bell operator.Our self-testing method shows both strong noise resistance and a high extractable randomness amount.Experimentally,we realize the self-testing of the maximally entangled state with fidelity 0.9749 and a set of complex projective measurements with average fidelity 0.9635.Moreover,we get a lower bound of 0.9302 bits of extractable randomness from outputs.These advances establish a practical pathway for implementing device-independent quantum information protocols with improved feasibility and operational flexibility. 展开更多
关键词 SELF-TESTING complex projective measurements quantum randomness ROBUSTNESS
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Orlicz-Brunn-Minkowski Inequalities for Complex Projection Bodies 被引量:2
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作者 WANG Wei LIU Lijuan 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2021年第1期8-14,共7页
Abardia and Bernig introduced the complex projection body and established the Brunn-Minkowski inequality for complex projection bodies.In this paper,we generalize their result and establish the Orlicz-Brunn-Minkowski ... Abardia and Bernig introduced the complex projection body and established the Brunn-Minkowski inequality for complex projection bodies.In this paper,we generalize their result and establish the Orlicz-Brunn-Minkowski inequality for complex projection bodies.And the Orlicz-Brunn-Minkowski inequality for polars of complex projection bodies is also obtained. 展开更多
关键词 convex body Orlicz addition complex projection body
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A novel fractional-order hyperchaotic complex system and its synchronization 被引量:1
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作者 金孟鑫 孙克辉 贺少波 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期151-160,共10页
A novel fractional-order hyperchaotic complex system is proposed by introducing the Caputo fractional-order derivative operator and a constant term to the complex simplified Lorenz system. The proposed system has diff... A novel fractional-order hyperchaotic complex system is proposed by introducing the Caputo fractional-order derivative operator and a constant term to the complex simplified Lorenz system. The proposed system has different numbers of equilibria for different ranges of parameters. The dynamics of the proposed system is investigated by means of phase portraits, Lyapunov exponents, bifurcation diagrams, and basins of attraction. The results show abundant dynamical characteristics. Particularly, the phenomena of extreme multistability as well as hidden attractors are discovered. In addition, the complex generalized projective synchronization is implemented between two fractional-order hyperchaotic complex systems with different fractional orders. Based on the fractional Lyapunov stability theorem, the synchronization controllers are designed, and the theoretical results are verified and demonstrated by numerical simulations. It lays the foundation for practical applications of the proposed system. 展开更多
关键词 fractional calculus complex hyperchaos simplified Lorenz system complex generalized projective synchronization
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Safety Risk Analysis of Large⁃scale Complex Project based on WBS⁃RBS and Interval Numbers 被引量:2
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作者 JIANG Weiyang HE Xiaoliang DU Hejia 《International Journal of Plant Engineering and Management》 2022年第3期129-143,共15页
Safety risks are essential to the success or failure of the large⁃scale complex projects.In order to assess and evaluate the safety risks of the large⁃scale complex projects scientifically,a risk assessment method of ... Safety risks are essential to the success or failure of the large⁃scale complex projects.In order to assess and evaluate the safety risks of the large⁃scale complex projects scientifically,a risk assessment method of work breakdown structure and risk breakdown structure(WBS⁃RBS)is proposed to identify the project risks.In this paper,interval numbers are used to evaluate the risk levels,weights are assigned automatically based on the complexity and risk degree of WBS to distinguish three types of nodes in WBS,and a risk assessment algorithm is designed to assess safety risk at all layers of the project.A case study is conducted to demonstrate how to apply the method.The results show the practicality,robustness and efficiency of our new method,which can be applied to different kinds of large⁃scale complex projects in reality. 展开更多
关键词 large⁃scale complex project risk assessment WBS⁃RBS assign weights automatically
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Discrete decision model and multi-agent simulation of the Liang Zong two-chain hierarchical organization in a complex project
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作者 MAI Qiang ZHAO Yueqiang AN Shi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第2期311-320,共10页
Different from the organization structure of complex projects in Western countries, the Liang Zong hierarchical organization structure of complex projects in China has two different chains, the chief-engineer chain an... Different from the organization structure of complex projects in Western countries, the Liang Zong hierarchical organization structure of complex projects in China has two different chains, the chief-engineer chain and the general-director chain,to handle the trade-off between technical and management decisions. However, previous works on organization search have mainly focused on the single-chain hierarchical organization in which all decisions are regarded as homogeneous. The heterogeneity and the interdependency between technical decisions and management decisions have been neglected. A two-chain hierarchical organization structure mapped from a real complex project is constructed. Then, a discrete decision model for a Liang Zong two-chain hierarchical organization in an NK model framework is proposed. This model proves that this kind of organization structure can reduce the search space by a large amount and that the search process should reach a final stable state more quickly. For a more complicated decision mechanism, a multi-agent simulation based on the above NK model is used to explore the effect of the two-chain organization structure on the speed, stability, and performance of the search process. The results provide three insights into how, compared with the single-chain hierarchical organization, the two-chain organization can improve the search process: it can reduce the number of iterations efficiently; the search is more stable because the search space is a smoother hill-like fitness landscape; in general, the search performance can be improved.However, when the organization structure is very complicated, the performance of a two-chain organization is inferior to that of a single-chain organization. These findings about the efficiency of the unique Chinese-style organization structure can be used to guide organization design for complex projects. 展开更多
关键词 complex project two-chain hierarchical organization discrete decision model multi-agent simulation
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Gorenstein Projective Dimensions of Complexes 被引量:8
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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 Totally Real Pseudo-Umbilical Submanifolds in a Complex Projective Space 被引量:7
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作者 ZHANG Liang 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2008年第2期421-428,共8页
Let M^n be a totally real submanifold in a complex projective space CP^(n+p).In this paper,we study the position of the parallel umbilical normal vector field of M^n in the normal bundle.By choosing a suitable frame f... Let M^n be a totally real submanifold in a complex projective space CP^(n+p).In this paper,we study the position of the parallel umbilical normal vector field of M^n in the normal bundle.By choosing a suitable frame field,we obtain a pinching theorem,in the case p>0, for the square of the length of the second fundamental form of a totally real pseudo-umbilical submanifold with parallel mean curvature vector. 展开更多
关键词 complex projective space totally real submanifolds pseudo-umbilical submanifolds parallel mean curvature vector
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ON THE EXISTENCE OF SINGULAR DIRECTIONS OF HOLOMORPHIC MAPS FROM THE UNIT DISK INTO P^n(C) 被引量:3
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作者 涂振汉 张莎莎 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1631-1639,共9页
This article proves the existence of Julia directions of value distribution of holomorphic mapping f from the unit disk into the n-dimensional complex projective spacePn(C) under the assumption limsupT(r,f)/log 1/... This article proves the existence of Julia directions of value distribution of holomorphic mapping f from the unit disk into the n-dimensional complex projective spacePn(C) under the assumption limsupT(r,f)/log 1/1-r = +∞ for hypersurfaces in general position. A heuristic principle concerning the existence of Julia directions of holomorphic mappings from the unit disk into Pn(C) is given also. 展开更多
关键词 complex projective spaces holomorphic mapping Julia direction Picard's theorem value distribution theory
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On Complete Totally Real Pseudo-Umbilical Submanifolds in a Complex Projective Space 被引量:4
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作者 Min LIU Wei Dong SONG 《Journal of Mathematical Research and Exposition》 CSCD 2011年第5期946-950,共5页
Let Mn be a totally real pseudo-umbilical submanifold in a complex projective space CPn+p. In this paper, we study the position of completeness of Mn. By choosing a suitable frame field, we obtain a rigidity theorem ... Let Mn be a totally real pseudo-umbilical submanifold in a complex projective space CPn+p. In this paper, we study the position of completeness of Mn. By choosing a suitable frame field, we obtain a rigidity theorem such that Mn becomes totally umbilical submanifold and improve the related results. 展开更多
关键词 complex projective space totally real submanifolds pseudo-umbilical submanifolds complete.
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ON THE SINGULAR DIRECTIONS OF VALUE DISTRIBUTION OF HOLOMORPHIC CURVES IN P^n(C) 被引量:2
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作者 涂振汉 李平丽 《Acta Mathematica Scientia》 SCIE CSCD 2006年第4期702-710,共9页
This article proves the existence of singular directions of value distribution theory for some transcendental holomorphic curves in the n-dimensional complex projective space P^n(C).. An example is given to compleme... This article proves the existence of singular directions of value distribution theory for some transcendental holomorphic curves in the n-dimensional complex projective space P^n(C).. An example is given to complement these results. 展开更多
关键词 complex projective spaces holomorphic mappings normal families singular directions and value distribution theory
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The Eigen Functions of the Complex Projective Space 被引量:1
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作者 Lu Qikeng Institute of Mathematics, Academia Sinica, Beijing 100080, China Institute of Mathematics, Shantou University, Shantou 515063, China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 1998年第1期1-8,共8页
In the complex n-dimensional projective space CP^n. let λ_p(=4p(p+n)) be the eigen vaiue of the Laplace-Beltrami operator and H_p be the space of all eigen functions of eigen value λ_p. The reproducing kernel h_p(z,... In the complex n-dimensional projective space CP^n. let λ_p(=4p(p+n)) be the eigen vaiue of the Laplace-Beltrami operator and H_p be the space of all eigen functions of eigen value λ_p. The reproducing kernel h_p(z, w) of H_p is constructed explicitly in this paper. and a system of complete orthogohal functions of H_p is construncted from h_p(z, w)(p=1,2…). 展开更多
关键词 complex projective space Reproducing kernel of eigen function
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NORMAL CRITERIA FOR A FAMILY OF HOLOMORPHIC CURVES
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作者 Daochun SUN Yingying HUO Fujie CHAI 《Acta Mathematica Scientia》 SCIE CSCD 2021年第6期1887-1895,共9页
In this paper,we extend the concept of holomorphic curves sharing hyperplanes and introduce definitions of restricted hyperplanes and partial shared hypersurfaces.Then,we prove several normal criteria of the family of... In this paper,we extend the concept of holomorphic curves sharing hyperplanes and introduce definitions of restricted hyperplanes and partial shared hypersurfaces.Then,we prove several normal criteria of the family of holomorphic curves and holomorphic mappings that concern restricted hyperplanes and partial shared hypersurfaces.These results generalize the Montel-type normal criterion of holomorphic curves. 展开更多
关键词 complex projective spaces holomorphic curves holomorphic mappings normal families restricted hyperplanes
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