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Discussion on the Complex Structure of Nilpotent Lie Groups Gk
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作者 Caiyu Du Yu Wang 《Open Journal of Applied Sciences》 2024年第6期1401-1411,共11页
Consider the real, simply-connected, connected, s-step nilpotent Lie group G endowed with a left-invariant, integrable almost complex structure J, which is nilpotent. Consider the simply-connected, connected nilpotent... Consider the real, simply-connected, connected, s-step nilpotent Lie group G endowed with a left-invariant, integrable almost complex structure J, which is nilpotent. Consider the simply-connected, connected nilpotent Lie group Gk, defined by the nilpotent Lie algebra g/ak, where g is the Lie algebra of G, and ak is an ideal of g. Then, J gives rise to an almost complex structure Jk on Gk. The main conclusion obtained is as follows: if the almost complex structure J of a nilpotent Lie group G is nilpotent, then J can give rise to a left-invariant integrable almost complex structure Jk on the nilpotent Lie group Gk, and Jk is also nilpotent. 展开更多
关键词 Almost Complex structure Nilpotent Lie group Nilpotent Lie Algebra
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Cost analysis of radical resection of malignant breast tumors under the China Healthcare Security Diagnosis Related Groups payment system
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作者 Yun-He Hu Ai-Dong Li 《World Journal of Clinical Cases》 SCIE 2024年第20期4174-4179,共6页
BACKGROUND Breast cancer is one of the most common malignant tumors in women worldwide and poses a severe threat to their health.Therefore,this study examined patients who underwent breast cancer surgery,analyzed hosp... BACKGROUND Breast cancer is one of the most common malignant tumors in women worldwide and poses a severe threat to their health.Therefore,this study examined patients who underwent breast cancer surgery,analyzed hospitalization costs and structure,and explored the impact of China Healthcare Security Diagnosis Related Groups(CHS-DRG)management on patient costs.It aimed to provide medical institutions with ways to reduce costs,optimize cost structures,reduce patient burden,and improve service efficiency.AIM To study the CHS-DRG payment system’s impact on breast cancer surgery costs.METHODS Using the CHS-DRG(version 1.1)grouping criteria,4073 patients,who underwent the radical resection of breast malignant tumors from January to December 2023,were included in the JA29 group;1028 patients were part of the CHS-DRG payment system,unlike the rest.Through an independent sample t-test,the length of hospital stay as well as total hospitalization,medicine and consumables,medical,nursing,medical technology,and management expenses were compared.Pearson’s correlation coefficient was used to test the cost correlation.RESULTS In terms of hospitalization expenses,patients in the CHS-DRG payment group had lower medical,nursing,and management expenses than those in the diagnosis-related group(DRG)non-payment group.For patients in the DRG payment group,the factors affecting the total hospitalization cost,in descending order of relevance,were medicine and consumable costs,consumable costs,medicine costs,medical costs,medical technology costs,management costs,nursing costs,and length of hospital stay.For patients in the DRG nonpayment group,the factors affecting the total hospitalization expenses in descending order of relevance were medicines and consumable expenses,consumable expenses,medical technology expenses,the cost of medicines,medical expenses,nursing expenses,length of hospital stay,and management expenses.CONCLUSION The CHS-DRG system can help control and reduce unnecessary medical expenses by controlling medicine costs,medical consumable costs,and the length of hospital stay while ensuring medical safety. 展开更多
关键词 China Healthcare Security Diagnosis Related groups Real-world study Radical resection of malignant breast tumors Hospitalization costs Cost structure Average length of stay
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Surgical treatment of liver cancer and pancreatic cancer under the China Healthcare Security Diagnosis Related Groups payment system
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作者 Yun-He Hu Fan Yu +1 位作者 Yu-Zhuo Zhou Ai-Dong Li 《World Journal of Clinical Cases》 SCIE 2024年第21期4673-4679,共7页
BACKGROUND Data from the World Health Organization’s International Agency for Research on Cancer reported that China had the highest prevalence of cancer and cancer deaths in 2022.Liver and pancreatic cancers account... BACKGROUND Data from the World Health Organization’s International Agency for Research on Cancer reported that China had the highest prevalence of cancer and cancer deaths in 2022.Liver and pancreatic cancers accounted for the highest number of new cases.Real-world data(RWD)is now widely preferred to traditional clinical trials in various fields of medicine and healthcare,as the traditional research approach often involves highly selected populations and interventions and controls that are strictly regulated.Additionally,research results from the RWD match global reality better than those from traditional clinical trials.AIM To analyze the cost disparity between surgical treatments for liver and pancreatic cancer under various factors.METHODS This study analyzed RWD 1137 cases within the HB1 group(patients who underwent pancreatectomy,hepatectomy,and/or shunt surgery)in 2023.It distinguished different expenditure categories,including medical,nursing,technical,management,drug,and consumable costs.Additionally,it assessed the contribution of each expenditure category to total hospital costs and performed cross-group comparisons using the non-parametric Kruskal–Wallis test.This study used the Steel–Dwass test for post-hoc multiple comparisons and the Spearman correlation coefficient to examine the relationships between variables.RESULTS The study found that in HB11 and HB13,the total hospitalization costs were significantly higher for pancreaticoduodenectomy than for pancreatectomy and hepatectomy.Although no significant difference was observed in the length of hospital stay between patients who underwent pancreaticoduodenectomy and pancreatectomy,both were significantly longer than those who underwent liver resection.In HB15,no significant difference was observed in the total cost of hospitalization between pancreaticoduodenectomy and pancreatectomy;however,both were significantly higher than those in hepatectomy.Additionally,the length of hospital stay was significantly longer for patients who underwent pancreaticoduodenectomy than for those who underwent pancreatectomy or liver resection.CONCLUSION China Healthcare Security Diagnosis Related Groups payment system positively impacts liver and pancreatic cancer surgeries by improving medical quality and controlling costs.Further research could refine this grouping system and ensure continuous effectiveness and sustainability. 展开更多
关键词 China health care security diagnosis-related groups Real-world study Liver cancer surgical treatment Pancreatic cancer surgical treatment Hospitalization costs Cost structure Average length of stay
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Dynamical Properties of Additive Cellular Automata over Finite Abelian Groups
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作者 邓爱平 王枫杰 伍陈晨 《Journal of Donghua University(English Edition)》 CAS 2023年第1期116-121,共6页
Some dynamical properties were discussed for additive cellular automata(CA)over finite abelian groups.These properties include surjection,ergodicity,sensitivity to initial conditions and positive expansivity.Some nece... Some dynamical properties were discussed for additive cellular automata(CA)over finite abelian groups.These properties include surjection,ergodicity,sensitivity to initial conditions and positive expansivity.Some necessary and sufficient conditions of determining ergodicity and sensitivity of the above additive CA were presented,respectively.A necessary condition for the positive expansivity of the above additive CA was given.The positive expansivity was proved to be preserved under the shift mappings for the general CA.The discussion was mainly based on the structure theorem of the finite abelian groups and the matrix associated with the global rule of the additive CA over the finite abelian p-groups. 展开更多
关键词 additive cellular automaton finite abelian group ERGODICITY sensitivity to initial condition positive expansivity
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Network autoregression model with grouped factor structures
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作者 ZHANG Zhiyuan ZHU Xuening 《中山大学学报(自然科学版)(中英文)》 CAS CSCD 北大核心 2023年第5期24-37,共14页
Network autoregression and factor model are effective methods for modeling network time series data.In this study,we propose a network autoregression model with a factor structure that incorporates a latent group stru... Network autoregression and factor model are effective methods for modeling network time series data.In this study,we propose a network autoregression model with a factor structure that incorporates a latent group structure to address nodal heterogeneity within the network.An iterative algorithm is employed to minimize a least-squares objective function,allowing for simultaneous estimation of both the parameters and the group structure.To determine the unknown number of groups and factors,a PIC criterion is introduced.Additionally,statistical inference of the estimated parameters is presented.To assess the validity of the proposed estimation and inference procedures,we conduct extensive numerical studies.We also demonstrate the utility of our model using a stock dataset obtained from the Chinese A-Share stock market. 展开更多
关键词 network autoregression factor structure HETEROGENEITY latent group structure network time series
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Improvisation of Node Mobility Using Cluster Routing-based Group Adaptive in MANET
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作者 J.Shanthini P.Punitha S.Karthik 《Computer Systems Science & Engineering》 SCIE EI 2023年第3期2619-2636,共18页
In today's Internet routing infrastructure,designers have addressed scal-ing concerns in routing constrained multiobjective optimization problems examining latency and mobility concerns as a secondary constrain.In... In today's Internet routing infrastructure,designers have addressed scal-ing concerns in routing constrained multiobjective optimization problems examining latency and mobility concerns as a secondary constrain.In tactical Mobile Ad-hoc Network(MANET),hubs can function based on the work plan in various social affairs and the internally connected hubs are almost having the related moving standards where the topology between one and the other are tightly coupled in steady support by considering the touchstone of hubs such as a self-sorted out,self-mending and self-administration.Clustering in the routing process is one of the key aspects to increase MANET performance by coordinat-ing the pathways using multiple criteria and analytics.We present a Group Adaptive Hybrid Routing Algorithm(GAHRA)for gathering portability,which pursues table-driven directing methodology in stable accumulations and on-request steering strategy for versatile situations.Based on this aspect,the research demonstrates an adjustable framework for commuting between the table-driven approach and the on-request approach,with the objectives of enhancing the out-put of MANET routing computation in each hub.Simulation analysis and replication results reveal that the proposed method is promising than a single well-known existing routing approach and is well-suited for sensitive MANET applications. 展开更多
关键词 Diplomatic mobile Ad-hoc network grouping mobility interior stable hybrid routing scheme adaptive switch structure clustering communication
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Brief Analysis of Group Structure in the Language Classroom
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作者 赵丹晨 《海外英语》 2013年第3X期218-220,共3页
Group activities are commonly used in second language classroom in recent years mostly because they encourage students to work together,helping each other.However,it is of great importance for teachers to notice the g... Group activities are commonly used in second language classroom in recent years mostly because they encourage students to work together,helping each other.However,it is of great importance for teachers to notice the group structures so that this class activity could play its important role in the classroom. 展开更多
关键词 group structure COOPERATIVE
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Group velocity distribution of Rayleigh waves and crustal and upper mantle velocity structure of the Chinese mainland and its vicinity 被引量:5
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作者 何正勤 丁志峰 +2 位作者 叶太兰 孙为国 张乃铃 《Acta Seismologica Sinica(English Edition)》 CSCD 2002年第3期269-275,共7页
Based on the long period digital surface wave data recorded by 11 CDSN stations and 11 IRIS stations, the dispersion curves of the group velocities of fundamental mode Rayleigh waves along 647 paths, with the periods ... Based on the long period digital surface wave data recorded by 11 CDSN stations and 11 IRIS stations, the dispersion curves of the group velocities of fundamental mode Rayleigh waves along 647 paths, with the periods from 10 s to 92 s, were measured by multi-filter. Their distribution at 25 central periods within the region of 18~54N, 70~140E was inverted by Dimtar-Yanovskaya method. Within the period from 10 s to 15.9 s, the group velocity distribution is laterally inhomogeneous and is closely related to geotectonic units, with two low velocity zones located in the Tarim basin and the East China Sea and its north regions, respectively. From 21 s to 33 s, the framework of tectonic blocks is revealed. From 36.6 s to 40 s, the lithospheric subdivision of the Chinese mainland is obviously uncovered, with distinct boundaries among the South-North seismic belt, the Tibetan plateau, the North China, the South China and the Northeast China. Four cross-sections of group velocity distribution with period along 30N, 38N, 90E and 120E, are discussed, respectively, which display the basic features of the crust and upper mantle of the Chinese mainland and its neighboring regions. There are distinguished velocity differences among the different tectonic blocks. There are low-velocity-zones (LVZ) in the middle crust of the eastern Tibetan plateau, high velocity featured as stable platform in the Tarim basin and the Yangtze platform, shallow and thick low-velocity-zone in the upper mantle of the North China. The upper mantle LVZ in the East China Sea and the Japan Sea is related to the frictional heat from the subduction of the Philippine slab and the strong extension since the Himalayan orogenic period. 展开更多
关键词 Rayleigh wave group velocity distribution crust and upper mantle velocity structure
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The Orders of Automorphism Group of p^6 Rank Groups 被引量:5
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作者 张新政 王勇 班桂宁 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第4期369-377,共9页
In this paper, we determine the order of automorphism group of p-groups in the third family ( Φ 3) and the fourth family ( Φ 4) in [1], whose order is p^6(p≥3). Here p denotes an odd prime.
关键词 P-group meta-abelian group automorphism group definite relation
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Finite Abelian Group of | A(G) |= 27pq 被引量:2
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作者 Huang Benwen (Department of Mathematics,Wuhan University, Wuhan 430072,China ) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第1期25-30,共6页
we have discussed structures of Abelian group G by order |A(G) |of automoorphism group and have obtained all types of finite Abelian grooup G when the order of A(G) equals 27pq(p,q are odd primmes).
关键词 abelian group automorphism group structure of group
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MULTIPLICATIVE GROUP AUTOMORPHISMS OF INVERTIBLE UPPER TRIANGULAR MATRICES OVER FIELDS 被引量:2
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作者 张显 曹重光 胡亚辉 《Acta Mathematica Scientia》 SCIE CSCD 2000年第4期515-521,共7页
Suppose F is a field of characteristic not 2 and F* its multiplicative group. Let T*n(F) be the multiplicative group of invertible upper triangular n x n matrices over F and STn(F) its subgroup {(aij) E T*n(F)aii = 1,... Suppose F is a field of characteristic not 2 and F* its multiplicative group. Let T*n(F) be the multiplicative group of invertible upper triangular n x n matrices over F and STn(F) its subgroup {(aij) E T*n(F)aii = 1, i}. This paper proves that f: T*n(F) → T*n(F) is a group automorphism if and only if there exist a matrix Q in T*n(F) and a field automorphism rs of F such that either where A = ((aij)), A-T is the transpose inverse of A, J = Ei n+1-i, and : i= 1T*n(F) → F* is a homomorphism which satisfies {(xIn)(x)x F*} = F* and {x F*(xIn)(x) = 1} = {1}. Simultaneously, they also determine the automorphisms of STn(F). 展开更多
关键词 group automorphism FIELD characteristi
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Two Important Classes of p-groups and the Orders of Their Automorphism Groups 被引量:2
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作者 BAN Gui-ning ZHANG Xin-zheng 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第4期491-493,共3页
In the paper we obtain two infinite classes of p-groups, calculate the orders of their automorphism groups and correct a mistake(perhaps misprinted) of Rodney James' paper in 1980.
关键词 finite group P-group automorphism order CLASSIFICATION
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Finitely Generated Torsion-free Nilpotent Groups Admitting an Automorphism of Prime Order 被引量:2
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作者 Xu Tao Liu He-guo 《Communications in Mathematical Research》 CSCD 2016年第2期167-172,共6页
Let G be a finitely generated torsion-free nilpotent group and a an automorphism of prime order p of G. If the map ψ : G → G defined by g^φ = [g, α] is surjective, then the nilpotent class of G is at most h(p),... Let G be a finitely generated torsion-free nilpotent group and a an automorphism of prime order p of G. If the map ψ : G → G defined by g^φ = [g, α] is surjective, then the nilpotent class of G is at most h(p), where h(p) is a function depending only on p. In particular, if α^3 = 1, then the nilpotent class of G is at most 2. 展开更多
关键词 torsion-free nilpotent group regular automorphism SURJECTIVITY
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Shake table test of soil-pile groups-bridge structure interaction in liquefiable ground 被引量:16
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作者 Tang Liang Ling Xianzhang +2 位作者 Xu Pengju Gao Xia Wang Dongsheng 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2010年第1期39-50,共12页
This paper describes a shake table test study on the seismic response of low-cap pile groups and a bridge structure in liquefiable ground. The soil profile, contained in a large-scale laminar shear box, consisted of a... This paper describes a shake table test study on the seismic response of low-cap pile groups and a bridge structure in liquefiable ground. The soil profile, contained in a large-scale laminar shear box, consisted of a horizontally saturated sand layer overlaid with a silty clay layer, with the simulated low-cap pile groups embedded. The container was excited in three E1 Centro earthquake events of different levels. Test results indicate that excessive pore pressure (EPP) during slight shaking only slightly accumulated, and the accumulation mainly occurred during strong shaking. The EPP was gradually enhanced as the amplitude and duration of the input acceleration increased. The acceleration response of the sand was remarkably influenced by soil liquefaction. As soil liquefaction occurred, the peak sand displacement gradually lagged behind the input acceleration; meanwhile, the sand displacement exhibited an increasing effect on the bending moment of the pile, and acceleration responses of the pile and the sand layer gradually changed from decreasing to increasing in the vertical direction from the bottom to the top. A jump variation of the bending moment on the pile was observed near the soil interface in all three input earthquake events. It is thought that the shake table tests could provide the groundwork for further seismic performance studies of low-cap pile groups used in bridges located on liquefiable groun. 展开更多
关键词 liquefiable ground seismic soil-pile-structure interaction pile groups of bridge shake table test
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The Orders of the Automorphism Groups of all Groups of Order p^5 被引量:1
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作者 蓝永红 惠敏 +1 位作者 班桂宁 邵明文 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第4期495-503,共9页
In this paper by techniques of group we give some formulae for solving the general quadratic equations of two variables over a finite field,completely calculate and uniformly deal with the orders of automorphism group... In this paper by techniques of group we give some formulae for solving the general quadratic equations of two variables over a finite field,completely calculate and uniformly deal with the orders of automorphism groups of all p-groups of orders less than p6 under the P Hall's concept of isoclinism,also make a number of corrections for orders of automorphism groups offered for a mistake or fault before. 展开更多
关键词 finite group P-group automorphism FIELD finite field
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THE BANACH-LIE GROUP OF LIE TRIPLE AUTOMORPHISMS OF AN H^*-ALGEBRA^* 被引量:1
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作者 A.J.Calderón Martín C.Martín González 《Acta Mathematica Scientia》 SCIE CSCD 2010年第4期1219-1226,共8页
We study the Banach-Lie group Ltaut(A) of Lie triple automorphisms of a complex associative H^*-algebra A. Some consequences about its Lie algebra, the algebra of Lie triple derivations of A, Ltder(A), are obtain... We study the Banach-Lie group Ltaut(A) of Lie triple automorphisms of a complex associative H^*-algebra A. Some consequences about its Lie algebra, the algebra of Lie triple derivations of A, Ltder(A), are obtained. For a topologically simple A, in the infinite-dimensional case we have Ltaut(A)0 = Aut(A) implying Ltder(A) = Der(A). In the finite-dimensional case Ltaut(A)0 is a direct product of Aut(A) and a certain subgroup of Lie derivations δ from A to its center, annihilating commutators. 展开更多
关键词 Banach-Lie group Lie triple automorphism Lie triple derivation
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Coset Structure of Spin Group 被引量:1
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作者 WANG Na WU Ke 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第6期987-994,共8页
This article considers One example is also given to take a the coset structure closer look at what of spin group via analyzing the expression of its representation. the coset and the subgroup are.
关键词 spin group group representation coset structure
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Vocal structure, behavior and partitioning of all 23 Pternistis spp. into homologous sound(and monophyletic) groups 被引量:2
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作者 Johann H.VAN NIEKERK 《Chinese Birds》 CSCD 2013年第3期210-231,共22页
The aims of this research were (1) to provide a description of spurfowl Pternistis spp. calls and their social context;(2) to describe the divergence of advertisement calls;and (3) to appropri-ate 23 spurfowl species ... The aims of this research were (1) to provide a description of spurfowl Pternistis spp. calls and their social context;(2) to describe the divergence of advertisement calls;and (3) to appropri-ate 23 spurfowl species to homologous sound groups which have been synthesized with recognized monophyletic groups within Pternistis spurfowls. Sound group partitioning was primarily based on male advertisement calls. A total of 218 recordings (rendering^300 identifiable calls) were analyzed covering 22 out of 23 spurfowl species in Africa. One species was assessed from written accounts. The repertoire size per spurfowl varies between 7 and 11 calls. Spurfowl calls were arranged into three broad categories including (1) advertisement calls;(2) maintenance calls including distress calls, juve-nile whining (“mews”), cheeps and comfort calls;and (3) male-female and female-offspring bonding calls. Spurfowl species were set out in eight sound groups of which five were more or less congruent with the monophyletic groups of Hall (1963), but sound groups produced more partitioning as Hall described only five groups relevant to Pternistis spp. The divergence of advertisement calls appar-ently minimizes hybridization between sympatric species but the“genetic distance”between spurfowl species is relatively small causing hybridization among spurfowl species. Despite the vocalizations of Hartlaub’s Spurfowl (P. hartlaubi) differing significantly from the rest of the spurfowls, sound analy-ses suggest that it remains within Pternistis. 展开更多
关键词 homologous sound groups vocal behavior DIVERGENCE phylogeny Pternistis vocal structure
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The Automorphism Group of the Lie Group T(D(V_N,F)) 被引量:1
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作者 CHENG Yong-sheng CHE Ying-tao 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第2期200-207,共8页
In this paper,the authors determine maximal connected automorphism group of the Lie transformation group T(D(VN,F)),which acting on the normal Siegel domain D(VN,F)is simple and transitive,and prove that the max... In this paper,the authors determine maximal connected automorphism group of the Lie transformation group T(D(VN,F)),which acting on the normal Siegel domain D(VN,F)is simple and transitive,and prove that the maximal connected automorphism group of T(D(VN,F))is its maximal connected inner automorphism group. 展开更多
关键词 normal Siegel domain automorphism group DERIVATION
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A Characterization of Metahomomorphisms on Abelian Groups 被引量:1
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作者 丁龙云 顾沛 《Northeastern Mathematical Journal》 CSCD 2006年第4期383-386,共4页
In this paper, a characterization of metahomomorphisms on Abelian groups is given.
关键词 metahomomorphism on group abelian group Yang-Baxter equation
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