• 제목/요약/키워드: ring extension

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THE INDEX OF THE CORESTRICTION OF A VALUED DIVISION ALGEBRA

  • Hwang, Yoon-Sung
    • 대한수학회지
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    • 제34권2호
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    • pp.279-284
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    • 1997
  • Let L/F be a finite separable extension of Henselian valued fields with same residue fields $\overline{L} = \overline{F}$. Let D be an inertially split division algebra over L, and let $^cD$ be the underlying division algebra of the corestriction $cor_{L/F} (D)$ of D. We show that the index $ind(^cD) of ^cD$ divides $[Z(\overline{D}) : Z(\overline {^cD})] \cdot ind(D), where Z(\overline{D})$ is the center of the residue division ring $\overline{D}$.

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EFFICIENT ALGORITHM FOR FINDING THE INVERSE AND THE GROUP INVERSE OF FLS $\gamma-CIRCULANT$ MATRIX

  • JIANG ZHAO-LIN;XU ZONG-BEN
    • Journal of applied mathematics & informatics
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    • 제18권1_2호
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    • pp.45-57
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    • 2005
  • An efficient algorithm for finding the inverse and the group inverse of the FLS $\gamma-circulant$ matrix is presented by Euclidean algorithm. Extension is made to compute the inverse of the FLS $\gamma-retrocirculant$ matrix by using the relationship between an FLS $\gamma-circulant$ matrix and an FLS $\gamma-retrocirculant$ matrix. Finally, some examples are given.

Incidences of Leaf Spots and Blights on Kiwifruit in Korea

  • Jeong, In-Ho;Lim, Myoung-Taek;Kim, Gyung-Hee;Han, Tae-Woong;Kim, Hong-Chul;Kim, Min-Ji;Park, Hyun-Su;Shin, Soon-Ho;Hur, Jae-Seoun;Shin, Jong-Sup;Koh, Young-Jin
    • The Plant Pathology Journal
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    • 제24권2호
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    • pp.125-130
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    • 2008
  • Various kinds of leaf spots and blights were found in kiwifruit (Actinidia deliciosa) orchards on 2006 in Korea. Disease incidences were quite variable between open-field and rain-proof shelter. Rate of diseased leaves was recorded as about 70% at open-field orchards in late season but use of rain-proof vinyl shelters alleviated the disease incidences by 20%. Angular leaf spots appeared at early infection stage on June and several other symptoms were also recognized as the disease developed afterward. On September, brown leaf blights were the most frequent, followed by grayish brown ring spots, silvering gray leaf blights, zonate leaf blights, dark brown ring spots and angular leaf spots at open-field orchards. Four fungal species were frequently isolated from the disease symptoms. Phomopsis sp. was the most predominant fungus associated with the leaf spot and blight symptoms on kiwifruit, followed by Glomerella cingulata, Alternaria alternata and Pestalo-tiopsis sp. Phomopsis sp. was commonly isolated from angular leaf spots, silvering gray leaf blights, and zonate brown leaf blights. G. cingulata, A. alternata and Pestalotiopsis sp. were isolated from grayish brown ring spots (anthracnose), brown ring spots and zonate dark brown leaf blights. Typical symptoms appeared on the wounded and unwounded leaves, which were inoculated by each of Phomopsis sp., G. cingulata, and Pestalotiopsis sp., but A. alternata caused symptoms only on the wounded leaves.

1차원 압밀점토의 응력해방에 의한 수직변형량과 현장재현 압밀시험에 관한 연구 (A Study on Reappeared Consolidation Test of In-situ Property and Vertical Deformation of Sample Due to Stress Release)

  • 김재영;고전직준
    • 한국지반공학회논문집
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    • 제24권7호
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    • pp.75-80
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    • 2008
  • 지중에서 채취한 불교란 포화점토시료는 응력해방으로 인해 연직방향으로 늘어나고 수평방향으로 수축한다. 현행 압밀시험법은 이와 같이 변형된 점토시료를 그대로 압밀링과 같은 크기로 성형하여 압밀시험을 수행하기 때문에 원지반의 거동을 명확히 나타내고 있다고 할 수 없다. 채취시료의 연직 신장변형량은 보링공에서 채취한 점토시료와 완전 되비빔한 슬러리로부터 재구성한 점토시료를 이용하여 측정한 결과, $1{\sim}2%$의 범위로 나타났다. 원위치의 압밀특성을 모사하는 시험방법은 표준압밀시험용 공시체보다 직경이 작고, 높이가 높은 공시체를 사용하여 원지반의 유효상 재압이 재하되었을 때 눌려 퍼져 압밀링의 내벽에 밀착하는 방법을 제안하였다.

핑크색 소륜 절화용 다수성 거베라 신품종 "썸머링" (A New Pink Mini Cut Flower Gerbera Cultivar, "Summer Ring")

  • 정용모;황주천;진영돈;김수경;이영병;권오창
    • 한국육종학회지
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    • 제40권1호
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    • pp.80-83
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    • 2008
  • 경남농업기술원 화훼육종연구소에서 '98년부터 교배조합육성을 위하여 국내의 재배농가와 종묘업체로부터 품종을 수집한 후, '01년 3월에 핑크색 대륜계의 'Grandeur'를 모본, 백색 소륜계의 'Nova Zembla'를 부본으로 인공교배를 실시하여 교배조합으로부터 284개의 종자를 획득하였다. 교배 후 결실이 된 조합은 채종 즉시 파종하였으며, 파종 1개월 후 248개의 유묘를 획득하였으며, 발아된 유묘는 본엽이 4~5매 전개되었을 때 화훼육종연구소 유리온실내의 선발 포장에 정식하였다. 그 후 교잡 1세대를 육묘하여 화색이 선명하고 수량이 많은 우수 2개체(01128-65, 94)를 1차로 선발하였다. 그 후 특성이 우수한 01128-94(경남 G-22)개체를 생장점배양에 의해 개체증식 후 화훼육종연구소 유리온실내의 특성검정 포장에 정식하여 2003년 6월부터 2004년 10월까지 3회에 걸쳐 생육 및 수량특성 검정을 실시하였다. 특성검정을 실시한 결과 화색, 화형, 수확량 등 품질과 수량이 우수하다고 판단되어 2005년 농작물 직무육성 신품종선정위원회의 심의를 거쳐 'Summer Ring'로 명명하였다. 'Summer Ring'은 화색이 선명한 핑크색의 반겹꽃 절화용으로 수량이 많고 안정된 소륜화로서 화색과 화심색이 잘 조화된 기호도가 높은 품종이다. 본당 수량은 연간 3회 검정 결과 평균 68.9개이며, 평균절화수명은 14.7일이다.

Biometric analysis hand parameters in young adults for prosthetic hand and ergonomic product applications

  • Gkionoul Nteli Chatzioglou;Yelda Pinar;Figen Govsa
    • Anatomy and Cell Biology
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    • 제57권2호
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    • pp.172-182
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    • 2024
  • This study aimed to evaluate the superficial anatomy, kinesiology, and functions of the hand to reveal its morphometry and apply the findings in various fields such as prosthetic hand and protective hand support product design. We examined 51 young adults (32 females, 19 males) aged between 18-30. Hand photographs were taken, and measurements were conducted using ImageJ software. Pearson correlation analysis was performed to determine the relationship between personal information and the parameters. The results of the measurements showed the average lengths of finger segments: thumb (49.5±5.5 mm), index finger (63.9±4.1 mm), middle finger (70.7±5.2 mm), ring finger (65.5±4.8 mm), and little finger (53.3±4.3 mm). Both females and males, the left index finger was measured longer than the right index finger. The right ring finger was found to be longer than the left in both sexes. Additionally, length differences between fingers in extended and maximally adducted positions were determined: thumb-index finger (56.1±6.2 mm), index-middle finger (10.7±4.1 mm), middle-ring finger (10.8±1.4 mm), and ring-little finger (25.6±2.7 mm). Other findings included the average radial natural angle (56.4°±10.5°), ulnar natural angle (23.4°±7.1°), radial deviation angle (65.2°±8.2°), ulnar deviation angle (51.2°±9.6°), and grasping/gripping angle (49.1°±5.8°). The average angles between fingers in maximum abduction positions were also measured: thumb-index finger (53.4°±6.5°), index-middle finger (17.2°±2.6°), middle-ring finger (14.3°±2.3°), and ring-little finger (32.1°±7.0°). The study examined the variability in the positioning of proximal interphalangeal joints during maximum metacarpophalangeal and proximal interphalangeal flexion, coinciding with maximum distal interphalangeal extension movements. The focal points of our observations were the asymmetrical and symmetrical arches formed by these joints. This study provides valuable hand parameters in young adults, which can be utilized in various applications such as prosthetic design, ergonomic product development, and hand-related research. The results highlight the significance of considering individual factors when assessing hand morphology and function.

INJECTIVE MODULES OVER ω-NOETHERIAN RINGS, II

  • Zhang, Jun;Wang, Fanggui;Kim, Hwankoo
    • 대한수학회지
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    • 제50권5호
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    • pp.1051-1066
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    • 2013
  • By utilizing known characterizations of ${\omega}$-Noetherian rings in terms of injective modules, we give more characterizations of ${\omega}$-Noetherian rings. More precisely, we show that a commutative ring R is ${\omega}$-Noetherian if and only if the direct limit of GV -torsion-free injective R-modules is injective; if and only if every R-module has a GV -torsion-free injective (pre)cover; if and only if the direct sum of injective envelopes of ${\omega}$-simple R-modules is injective; if and only if the essential extension of the direct sum of GV -torsion-free injective R-modules is the direct sum of GV -torsion-free injective R-modules; if and only if every $\mathfrak{F}_{w,f}(R)$-injective ${\omega}$-module is injective; if and only if every GV-torsion-free R-module admits an $i$-decomposition.

Imidazole Ring-Opened DNA Purines and Their Biological Significance

  • Barbara, Tudek
    • BMB Reports
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    • 제36권1호
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    • pp.12-19
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    • 2003
  • Fragmentation of purine imidazole ring and production of formamidopyrimidines in deoxynucleosides (Fapy lesions) occurs upon DNA oxidation as well as upon spontaneous or alkali-triggered rearrangement of certain alkylated bases. Many chemotherapeutic agents such as cyclophosphamide or thiotepa produce such lesions in DNA. Unsubstituted FapyA and FapyG, formed upon DNA oxidation cause moderate inhibition of DNA synthesis, which is DNA polymerase and sequence dependent. Fapy-7MeG, a methylated counterpart of FapyG-, a efficiently inhibits DNA replication in vitro and in E.coli, however its mutagenic potency is low. This is probably due to preferential incorporation of cytosine opposite Fapy-7MeG and preferential extension of Fapy-7MeG:C pair. In contrast, FapyA and Fapy-7MeA possess miscoding potential. Both lesions in SOS induced E.coli preferentially mispair with cytosine giving rise to A$\rightarrow$G transitions. Fapy lesions substituted with longer chain alkyl groups also show simult aneous lethal and mutagenic properties. Fapy lesions are actively eliminated from DNA by repair glycosylases specific for oxidized purines and pyrimidines both in bacteria and eukaryotic cells. Bacterial enzymes include E.coli formamidopyrimidine-DNA-glycosylase (Fpg protein), endonuclease III (Nth protein) and endonuclease VIII (Nei protein).

(m, n)-CLOSED δ-PRIMARY IDEALS IN AMALGAMATION

  • Mohammad Hamoda;Mohammed Issoual
    • 대한수학회논문집
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    • 제39권3호
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    • pp.575-583
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    • 2024
  • Let R be a commutative ring with 1 ≠ 0. Let Id(R) be the set of all ideals of R and let δ : Id(R) → Id(R) be a function. Then δ is called an expansion function of the ideals of R if whenever L, I, J are ideals of R with J ⊆ I, then L ⊆ δ (L) and δ (J) ⊆ δ (I). Let δ be an expansion function of the ideals of R and m ≥ n > 0 be positive integers. Then a proper ideal I of R is called an (m, n)-closed δ-primary ideal (resp., weakly (m, n)-closed δ-primary ideal ) if am ∈ I for some a ∈ R implies an ∈ δ(I) (resp., if 0 ≠ am ∈ I for some a ∈ R implies an ∈ δ(I)). Let f : A → B be a ring homomorphism and let J be an ideal of B. This paper investigates the concept of (m, n)-closed δ-primary ideals in the amalgamation of A with B along J with respect to f denoted by A ⋈f J.

재생냉각 연소기의 냉각기구에 따른 특성 파악 (Investigation of Characteristics for Cooling Parameters of a Combustor in Liquid Rocket Combustors)

  • 김홍집;최환석
    • 한국추진공학회지
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    • 제14권5호
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    • pp.45-50
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    • 2010
  • 연료링의 위치 및 열차폐 코팅의 종류에 따른 연소기의 재생냉각 특성을 검토하였다. 연료링을 노즐의 중간 부분에 위치시키고 냉각채널을 분기시켜서 설계하는 방법이 열적으로 타당함을 확인하였다. 또한 복합재를 이용한 노즐확장부가 적용 가능한 기술적 상황이라면, 팽창비가 높고 열유속이 낮은 노즐 후류 부분은 이를 이용하는 것이 매우 적절하다고 판단된다. 적용 가능한 열차폐 코팅 중에서 30톤급 연소기 및 가스발생기 개발과정에서 사용했던 $Y_2O_3$ stabilized $ZrO_2$과 내산화성이 우수한 Ni/Cr을 고려하였다. 내산화성이 우수한 Ni/Cr에 비해 세라믹 코팅($Y_2O_3$ stabilized $ZrO_2$)이 열차폐 효과가 우수한 것으로 파악되었다.