In this paper,we investigate the comparability structure over exchange rings.It is shown that the subdirect product of an exchange ring with stable range one and an exchange ring satisfying the comparability is also a...In this paper,we investigate the comparability structure over exchange rings.It is shown that the subdirect product of an exchange ring with stable range one and an exchange ring satisfying the comparability is also an exchange ring satisfying the comparability.This provides a new class of exchange rings satisfying the comparability.Furthermore,we investigate the s-comparability over exchange rings.This generalizes the corresponding results of Goodearl and Chen.展开更多
We obtaim a new substitution for modules over exchange rings satisfving related compara- bilitv. Also we investigate the structure of modules over exchange rings satisfying power comparability and provide a new class ...We obtaim a new substitution for modules over exchange rings satisfving related compara- bilitv. Also we investigate the structure of modules over exchange rings satisfying power comparability and provide a new class of exchange rings satisfying related comparability.展开更多
Let R be an exchange ring with primitive factors artinian. We prove that there exists a u∈U（R） such that 1R ± u ∈ U（R）, if and only if for any a ∈ R, there exists a u ∈ U（R） such that a ± u∈ U（R...Let R be an exchange ring with primitive factors artinian. We prove that there exists a u∈U（R） such that 1R ± u ∈ U（R）, if and only if for any a ∈ R, there exists a u ∈ U（R） such that a ± u∈ U（R）. Phrthermore, we prove that, for any A ∈ Mn（R）（n ≥ 2）, there exists a U ∈ GLn（R） such that A ± U ∈ GLn（R）.展开更多
In this paper. we study the endomorphism rings of regular modules.We give sufficient conditions on a regular projective module P such that End_R(P) has stable range one.
An ATM ring switching testbed is proposed in this paper. Two practical applications for the ATMring exchange are aimed, one is used ai ATM LAM/MAN, another is for rural local ATM exchange. A dis-tributed swithching an...An ATM ring switching testbed is proposed in this paper. Two practical applications for the ATMring exchange are aimed, one is used ai ATM LAM/MAN, another is for rural local ATM exchange. A dis-tributed swithching and control architecture is designed. together with a modular and flexible hardware and soft-ware structure which permits a rapid and easy introduction and testing of new, services. Hierarchical VP and VCswitching is organized, three AALs (AAL1, AAL4 & AAL5) are supported to provide conaretion-oriented andconnectionless services Broadcasting, multicasting and multi-conferencing functions are achieved at no extra cost,and imerworking with the existing network is emphasized. The constucticon of ring access node is described. As anexample a PDH-ATM interface is given.展开更多
基金This work is supported by the National Natural Science Foundation of China (Grant No.19801012)the Ministry of Education of China.
文摘In this paper,we investigate the comparability structure over exchange rings.It is shown that the subdirect product of an exchange ring with stable range one and an exchange ring satisfying the comparability is also an exchange ring satisfying the comparability.This provides a new class of exchange rings satisfying the comparability.Furthermore,we investigate the s-comparability over exchange rings.This generalizes the corresponding results of Goodearl and Chen.
基金This work is supported by the National Natural Science Foundation of China (Grant No. 19801012. 19531020).
文摘We obtaim a new substitution for modules over exchange rings satisfving related compara- bilitv. Also we investigate the structure of modules over exchange rings satisfying power comparability and provide a new class of exchange rings satisfying related comparability.
基金Supported by Natural Science Foundation of Hunan Province(04JJ40003)
文摘Let R be an exchange ring with primitive factors artinian. We prove that there exists a u∈U（R） such that 1R ± u ∈ U（R）, if and only if for any a ∈ R, there exists a u ∈ U（R） such that a ± u∈ U（R）. Phrthermore, we prove that, for any A ∈ Mn（R）（n ≥ 2）, there exists a U ∈ GLn（R） such that A ± U ∈ GLn（R）.
基金The author is supported by the NNSF of China (No. 19601009)
文摘In this paper. we study the endomorphism rings of regular modules.We give sufficient conditions on a regular projective module P such that End_R(P) has stable range one.
文摘An ATM ring switching testbed is proposed in this paper. Two practical applications for the ATMring exchange are aimed, one is used ai ATM LAM/MAN, another is for rural local ATM exchange. A dis-tributed swithching and control architecture is designed. together with a modular and flexible hardware and soft-ware structure which permits a rapid and easy introduction and testing of new, services. Hierarchical VP and VCswitching is organized, three AALs (AAL1, AAL4 & AAL5) are supported to provide conaretion-oriented andconnectionless services Broadcasting, multicasting and multi-conferencing functions are achieved at no extra cost,and imerworking with the existing network is emphasized. The constucticon of ring access node is described. As anexample a PDH-ATM interface is given.
