• 제목/요약/키워드: Yazd

검색결과 173건 처리시간 0.022초

ON QUASI-EXACT SEQUENCES

  • ANVARIYEH, S.M.;DAVVAZ, B.
    • 대한수학회보
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    • 제42권1호
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    • pp.149-155
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    • 2005
  • The notion of U-exact sequence (or quasi-exact sequence) of modules was introduced by Davvaz and Parnian-Garamaleky as a generalization of exact sequences. In this paper, we prove further results about quasi-exact sequences. In particular, we give a generalization of Schanuel's Lemma. Also we obtain some relation-ship between quasi-exact sequences and superfluous (or essential) submodules.

A GENERALIZATION OF HOMOLOGICAL ALGEBRA

  • Davvaz, B.;Shabani-Solt, H.
    • 대한수학회지
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    • 제39권6호
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    • pp.881-898
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    • 2002
  • Our aim in this paper is to introduce a generalization of some notions in homological algebra. We define the concepts of chain U-complex, U-homology, chain (U, U')-map, chain (U, U')-homotopy and $\mu$-functor. We also obtain some interesting results. We use these results to find a generalization of Lambek Lemma, Snake Lemma, Connecting Homomorphism and Exact Triangle.

The Effect of Twist Liveliness on the Woven Fabric Distortion

  • Alamdar-Yazdi A.;Khojasteh M.R.
    • Fibers and Polymers
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    • 제7권1호
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    • pp.79-84
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    • 2006
  • This paper deals with the grey fabric deformation during relaxation. It investigates the effect of twist direction and twist liveliness on the 2/2 twill weave woven fabric distortion, during relaxation This experimental work shows that twist liveliness increases the natural tendency of the twill weave woven fabric to skew. In addition when the twist direction of the warp and weft is opposite to each other the bias curling occurs too.

STUDY ON CLEAN ORDERED RINGS DERIVED FROM CLEAN ORDERED KRASNER HYPERRINGS

  • Omidi, Saber;Davvaz, Bijan
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제25권2호
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    • pp.115-125
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    • 2018
  • In this paper, we introduce the notion of a clean ordered Krasner hyperring and investigate some properties of it. Now, let (R, +, ${\cdot}$, ${\leq}$) be a clean ordered Krasner hyperring. The following is a natural question to ask: Is there a strongly regular relation ${\sigma}$ on R for which $R/{\sigma}$ is a clean ordered ring? Our motivation to write the present paper is reply to the above question.

Acetalization of Carbonyl Compounds by Using Silica-bound Sulfuric Acid under Green Condition

  • Mirjalili, Bi Bi Fatemeh;Zolfigol, Mohammad Ali;Bamoniri, Abdolhamid;Hazar, Azizeh
    • Bulletin of the Korean Chemical Society
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    • 제25권6호
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    • pp.865-868
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    • 2004
  • Aldehydes and ketones were converted to their corresponding acetals in the presence of silica-bound sulfuric acid in n-hexane under mild and heterogeneous conditions with excellent yields.

SOME TOPOLOGICAL ASPECTS OF GENERALIZED GROUPS AND PSEUDONORMS ON THEM

  • Zand, Mohammad Reza Ahmadi;Rostami, Salimeh
    • 호남수학학술지
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    • 제40권4호
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    • pp.661-669
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    • 2018
  • In this paper, we introduce and study the notion of a pseudonorm on a generalized group. Let G be a topological generalized group and let the family $\{G_x\}_{x{\in}e(G)}$ be locally finite. Then, we show that G is completely regular. Also, some well known results are generalized.