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한국산 쑥속의 체세포 염색체수에 의한 분류학적 연구 (A taxonomic study of Korean Artemisia L. using somatic chromosome numbers)

  • 박명순;장진;정규영
    • 식물분류학회지
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    • 제39권4호
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    • pp.247-253
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    • 2009
  • 한국산 쑥속 20분류군의 분류를 위하여 체세포 염색체수를 조사하였다. 본 연구에서 취급된 분류군들의 체세포 염색체수는 2n = 16, 18, 34, 36, 50, 52, 54로서 기본 염색체수는 x=8, 9, 10, 13, 17이었으며, 실제비쑥(A. japonica var. angustissima 2n = 36)의 체세포염색체수는 본 연구에서 처음으로 밝혀졌다. 사철쑥 (A. capillaris 2n = 18), 섬쑥(A. japonica var. hallaisanensis 2n = 36), 갯제비쑥(A. japonica subsp. littoricola 2n = 36), 개똥쑥(A. annua 2n = 18), 개사철쑥(A. carvifolia 2n = 18), 큰비쑥(A. fukudo 2n = 16), 맑은대쑥(A. keiskeana 2n = 18), 넓은잎외잎쑥(A. stolonifera 2n = 36), 그늘쑥(A. sylvatica 2n = 16), 물쑥(A. selengensis 2n = 36), 산쑥 (A. montana 2n = 52), 뺑쑥(A. lancea 2n = 16), 산흰쑥(A. sieversiana 2n = 18) 등의 13분류군의 염색체수는 기존 보고와 일치하였으며, 기존 보고와 다르게 파악된 종류는 제비쑥(A. japonica var. japonica 2n = 18, 36 vs 2n = 36), 더위지기(A. sacrorum 2n = 18, 54 vs 2n = 54), 덤불쑥(A. rubripes 2n = 16, 34 vs 2n = 16), 쑥(A. indica 2n = 34, 36 vs 2n = 34), 참쑥(A. codonocephala 2n = 18, 50, 54 vs 2n = 50), 황해쑥(A. argyi 2n = 34, 36, 50 vs 2n = 34)의 6분류군이었다. 한국산 쑥속의 체세포 염색체수는 제비쑥, 더위지기, 참쑥, 황해쑥, 산쑥, 그늘쑥의 분류에 매우 유용한 형질이었다.

대학 엘리트 카나디언 선수들의 어깨·허리·무릎 관절의 등속성 근기능 평가 및 진단 (Assessment of Isokinetic Muscle Function in Elite Canadian College Paddlers)

  • 신광택;안창규;손지훈
    • 한국산학기술학회논문지
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    • 제14권1호
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    • pp.229-238
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    • 2013
  • 본 연구는 대학 엘리트 카나디언 선수들의 등속성 근기능을 검사 및 진단하여 선수들의 기능 향상 및 상해예방을 위한 훈련 방법론에 대한 조언을 하고자 함에 목적이 있다. 경주 소재 D 대학의 평균 8.5년의 경력을 가진 8명의 엘리트 선수들이 실험에 참가했으며, Biodex system III, Biodex stabilizer system, THP 2, Inbody 720이 근기능 검사(peak torque, average power, work fatigue), 동적 균형 검사, 신체성분 검사를 위해 사용되었다. 등속성 근기능 검사는 어깨와 허리, 무릎 관절에 대하여 실시하였으며, 측정 후 동측 불균형과 좌 우측 불균형 정도를 평가하였다. 검사 결과 A3, A4, A5, A6, A8 선수는 어깨의 근력과 파워 훈련이, A1, A2, A7, A8 선수는 어깨의 근지구력 훈련이 필요한 것으로 평가되었다. A2, A5, A8 선수는 허리의 근력과 파워 강화 훈련이 필요하였고, A1, A8 선수는 허리의 근지구력 강화 훈련이 필요하였다. 대부분의 선수들은 무릎과 허리의 동측 근력비가 정상적이지 못했는데, 이의 개선을 위해 A2, A3, A4, A8 선수는 복근의 강화가 필요했고 A3, A5, A6, A7, A8 선수는 햄스트링의 강화가 요구되었다. 선수들의 BMI 평균은 24.90 $kg/m^2$, 체지방율은 12.23%, 반응시간 평균은 324 msec, 밸런스 점수는 각각 2.0 미만으로 나타났다. 이러한 결과를 종합해 볼 때, 카나디언 엘리트 선수들은 근력 불균형에 의한 경기력 저하와 상해 잠재 위험성이 있으므로 정기적인 근기능 검사를 통한 관리와 함께 적절한 훈련 처방이 필요할 것이라 생각된다.

LIE TRIPLE DERIVATIONS ON FACTOR VON NEUMANN ALGEBRAS

  • Liu, Lei
    • 대한수학회보
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    • 제52권2호
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    • pp.581-591
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    • 2015
  • Let $\mathcal{A}$ be a factor von Neumann algebra with dimension greater than 1. We prove that if a linear map ${\delta}:\mathcal{A}{\rightarrow}\mathcal{A}$ satisfies $${\delta}([[a,b],c])=[[{\delta}(a),b],c]+[[a,{\delta}(b),c]+[[a,b],{\delta}(c)]$$ for any $a,b,c{\in}\mathcal{A}$ with ab = 0 (resp. ab = P, where P is a fixed nontrivial projection of $\mathcal{A}$), then there exist an operator $T{\in}\mathcal{A}$ and a linear map $f:\mathcal{A}{\rightarrow}\mathbb{C}I$ vanishing at every second commutator [[a, b], c] with ab = 0 (resp. ab = P) such that ${\delta}(a)=aT-Ta+f(a)$ for any $a{\in}\mathcal{A}$.

영화관 내부공간에서 관람자세와 행동특성에 관한 연구 (A Study on Seating Posture & Behavioral Characteristic in Interior Space of a Cinema)

  • 김종성;김종하;최주영;이정호
    • 한국실내디자인학회논문집
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    • 제17권3호
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    • pp.131-138
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    • 2008
  • This research is on a seating posture happening at a chair in a cinema and looked into various changes in a posture through the analysis of bodily movement in a established space like a cinema. Through the behavioral analysis of a seating posture in a limited space, each behavioral characteristic shown by a male and female and interdependent relations with a limited space were grasped. The conclusion through the above research work was as follows: 1) This research suggested a frame of analysis by dividing a seating posture into the side and upper part and was able to analyze its subsequent change characteristic of a seating posture by a male and female. 2) As for the side posture, a male was found to change fewer postures than a female, but as for the upper posture, there appeared a high frequency in posture change in case of a female. 3) As for time of staying in the side posture, a female was found to keep up a specific posture, and relatively a male changes his postures frequently while appreciating a movie; likely, as for the upper posture, it was found out that there existed a difference between the preference for the upper posture and time to keep it up. 4) A male and female were establishing a comfortable environment through their change in a posture, and there appeared changes in a posture the most within every 10 minutes in both the side and upper part postures. 5) As for the correlation between a initial posture and keep-up posture, it was found that a male tend to pursue a comfortable posture as time goes by, while a female kept up a comfortable one from her initial seating posture.

UV-A로 유발된 RNase A의 변성에 대한 UV 차단렌즈의 작용 (The effect of UV blocking lens on the denaturation of RNase A induced by UV-A)

  • 박영민;박충서;이흠숙;박미정
    • 한국안광학회지
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    • 제12권1호
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    • pp.9-15
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    • 2007
  • 본 연구는 UV-A 노출에 의해 유발된 안구 내에 존재하는 단백질 효소 중의 하나인 ribonuclease A(RNase A)의 변성을 차단할 수 있는 안경렌즈의 적절한 UV-A 차단율을 알아보기 위해 수행하였다. RNase A를 1, 3, 6, 24, 48, 72, 96시간 동안 365 nm의 UV-A에 노출시켜 노출시간에 따른 단백질의 변성 정도를 아크릴 아미드 겔 전기영동법으로 확인하였다. 또한, 20%, 50%, 80%, 99% UV 차단 효과를 가진 안경렌즈로 UV-A를 차단하였을 때 RNase A의 변성이 억제될 수 있는 지를 알아보았다. RNase의 변성은 1시간 동안의 UV 노출에 의해서도 유발되었으며, UV-A 노출시간이 길어질수록 그 정도는 심해졌다. 1시간의 UV-A 노출에 의해 유발된 미세한 RNase A의 변성은 20% 정도의 UV-A 차단으로 충분히 예방될 수 있었다. UV-A를 3시간 동안 노출하였을 때는 50%이상의 UV-A 차단율을 가진 렌즈가 RNase A의 변성을 막을 수 있었다. 6시간 동안 UV-A에 노출되었을 때에는 99%의 렌즈로 차단하였을 때조차도 RNase A의 변성이 완벽하게 차단되지 못했다. 그러나 96시간 동안 UV-A에 노출되었을 때 나타나는 심각한 단백질의 변성이 99%의 UV-A 차단 렌즈를 사용하였을 경우 크게 감소하였다.

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수면 박탈이 혈동태에 끼치는 영향 (The Study on the effects of hemodynamics in sleep deprivation)

  • 김경철
    • 대한예방한의학회지
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    • 제3권1호
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    • pp.125-145
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    • 1999
  • The effects of Wang-ttum, Magnetic Water, Magnetic field and Sibjeondaebotang on hemodynamics in sleep deprivation were studied. The results as follows; 1. In case of Wang-ttum operated group, significant changes were observed at 12 p.m., 2 a.m., 4 a.m. in maximum blood pressure for the first and second overnight stay and at 2 a.m. for the third and, respectively, average blood pressure at 12 p.m., 2 a.m. for the 1st and 2nd overnight stay, minimum blood pressure at 10 p.m.. 12 p.m.. 2 a.m. for the 1st overnight stay and at 10 p.m., 12 p.m. for the 2nd and at 12 p.m. for the 3rd, pulse rate at 12 p.m., 2 a.m., 4 a.m., 6 a.m., for 1st and 2nd and at 2 a.m., 4 a.m. for the 3rd and 4th, TP-KS at 12 p.m., 2 a.m., 4 a.m., 6 a.m. for the 1st and 2nd and at 2 a.m., 4 a.m., 6 a.m. for the 3rd, PRP at 10 p.m., 12 p.m., 2 a.m., 4 a.m., 6 a.m. for the 1st and 2nd and at 12 p.m., 2 a.m., 4 a.m. for the 3rd and at 2 a.m., 4 a.m. for the 4th, TPR at 10 p.m., 12 p.m., 2 a.m., 4 a.m., 6 a.m. from 1st to 4th overnight stay. 2. In case of taking magnetic water group, significant changes were observed at 2 a.m., 4 a.m. in pulse rate for the 1st overnight stay and, respectively, PRP at 2 a.m. for the 1st, TRP at 10 p.m., 12 p.m., 2 a.m., 4 a.m., 6 a.m. for the 1st and 4th. 3. In case of attaching magnet group, TPR was significantly observed at 10 p.m. for the 1st overnight stay. 4. In case of medicating Sibjeondaebotang group, significant changes were observed at 10 p.m., 12 p.m., 2 a.m., 4 a.m., 6 a.m. in maximum blood pressure for the 1st and 2nd overnight stay and at 12 p.m., 2 a.m., 4 a.m., 6 a.m. for the 3rd and at 2 a.m., 4 a.m., 6 a.m. for the 4th and, respectively, average blood pressure at 10 p.m., 12 p.m. for the 1st and 2nd and at 10 p.m. for the 3rd and 4th, minimum blood pressure at 10 p.m., 12 p.m. from 1st to 4th, pulse rate at 2 a.m., 4 a.m., 6 a.m. from 1st to 3rd and at 2 a.m., 4 a.m. for the 4th, TP-KS at 10 p.m., 12 p.m., 2 a.m., 4a.m., 6 a.m. for the 1st and at 10 p.m., 2 a.m., 4 a.m., 6 a.m. for the 2nd and at 2 a.m., 4 a.m., 6 a.m. for the 3rd and at 6 a.m. for the 4th, PRP at 12 p.m., 2 a.m., 4 a.m., 6 a.m. for the 1st and at 10 p.m., 12 p.m., 2 a.m., 4 a.m., 6 a.m. for the 2nd and 3rd and at 12 p.m., 2 a.m., 4 a.m., 6 a.m. for the 4th, TPR at 10 p.m., 12 p.m., 2 a.m., 4 a.m., 6 a.m. from 1st to 4th. As mentioned obove, the effects of Wangttum and Sibjeondaebotang on hemodynamics in sleep deprivation were observed both the impulse of SIM-YANG and mutual function of QI-HYOL. The effects of Magnetic water and Magnetic field were observed the side of mutual function of QI-HYOL.

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수차용 봉수장치의 마찰.마모특성에 관한 실험적 연구 (Experimental Study on the Friction and Wear Characteristics of Contact Sealing Unit for a Water Turbine)

  • 김청균;신인철;임광현
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2006년도 추계학술대회
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    • pp.515-518
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    • 2006
  • This paper presents the friction and wear characteristics of contact type sealing unit for a water turbine of a small hydro-power generation, which Is to stop a leakage of a circulating water from a outside of an impeller to an inside of a rolling bearing. The surface wear strongly affect to the seal life of a mechanical face seal. In this study, the hardness of a stainless steel in which is a heat-treated is 892.8 in Vickers hardness and the hardness of silicone carbide of SiC is 714.1 in Vickers hardness. The surface hardness of a heat-treated stainless steel is 25% high compared with that of a ceramic material of SiC. The contact modes of rubbing surfaces aye a dry friction a water film friction and a mixed friction that is contaminated by a dust, silt and moistures, etc. These two factors of a contact rubbing modes and a material property are very important parameters on the tribological performance such as a friction and wear between a seal ring and a seal seat. The experimental result shows that the surface hardness of a seal material is very important on the friction coefficient and a wear volume. Thus, the results recommend higher hardness of a seal material, which may reduce a friction loss and increase a wear life of primary seal components

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NOTE ON GOOD IDEALS IN GORENSTEIN LOCAL RINGS

  • Kim, Mee-Kyoung
    • 대한수학회보
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    • 제39권3호
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    • pp.479-484
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    • 2002
  • Let I be an ideal in a Gorenstein local ring A with the maximal ideal m and d = dim A. Then we say that I is a good ideal in A, if I contains a reduction $Q=(a_1,a_2,...,a_d)$ generated by d elements in A and $G(I)=\bigoplus_{n\geq0}I^n/I^{n+1}$ of I is a Gorenstein ring with a(G(I)) = 1-d, where a(G(I)) denotes the a-invariant of G(I). Let S = A[Q/a$_1$] and P = mS. In this paper, we show that the following conditions are equivalent. (1) $I^2$ = QI and I = Q:I. (2) $I^2S$ = $a_1$IS and IS = $a_1$S:sIS. (3) $I^2$Sp = $a_1$ISp and ISp = $a_1$Sp :sp ISp. We denote by $X_A(Q)$ the set of good ideals I in $X_A(Q)$ such that I contains Q as a reduction. As a Corollary of this result, we show that $I\inX_A(Q)\Leftrightarrow\IS_P\inX_{SP}(Qp)$.

OPERATORS A, B FOR WHICH THE ALUTHGE TRANSFORM ${\tilde{AB}}$ IS A GENERALISED n-PROJECTION

  • Bhagwati P. Duggal;In Hyoun Kim
    • 대한수학회보
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    • 제60권6호
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    • pp.1555-1566
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    • 2023
  • A Hilbert space operator A ∈ B(H) is a generalised n-projection, denoted A ∈ (G-n-P), if A*n = A. (G-n-P)-operators A are normal operators with finitely countable spectra σ(A), subsets of the set $\{0\}\,{\cup}\,\{\sqrt[n+1]{1}\}.$ The Aluthge transform à of A ∈ B(H) may be (G - n - P) without A being (G - n - P). For doubly commuting operators A, B ∈ B(H) such that σ(AB) = σ(A)σ(B) and ${\parallel}A{\parallel}\,{\parallel}B{\parallel}\;{\leq}\;{\parallel}{\tilde{AB}}{\parallel},$ ${\tilde{AB}}\;{\in}\;(G\,-\,n\,-\,P)$ if and only if $A\;=\;{\parallel}{\tilde{A}}{\parallel}\,(A_{00}\,{\oplus}\,(A_0\,{\oplus}\,A_u))$ and $B\;=\;{\parallel}{\tilde{B}}{\parallel}\,(B_0\,{\oplus}\,B_u),$ where A00 and B0, and A0 ⊕ Au and Bu, doubly commute, A00B0 and A0 are 2 nilpotent, Au and Bu are unitaries, A*nu = Au and B*nu = Bu. Furthermore, a necessary and sufficient condition for the operators αA, βB, αà and ${\beta}{\tilde{B}},\;{\alpha}\,=\,\frac{1}{{\parallel}{\tilde{A}}{\parallel}}$ and ${\beta}\,=\,\frac{1}{{\parallel}{\tilde{B}}{\parallel}},$ to be (G - n - P) is that A and B are spectrally normaloid at 0.

전형식적 증명의 의미와 교육학적 의의에 관한 연구 (A Study on the meaning of preformal proof and its didactical significance)

  • 류성림
    • 대한수학교육학회지:수학교육학연구
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    • 제8권1호
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    • pp.313-326
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    • 1998
  • The purpose of this study is to verify the meaning of preformal proof and its didactical significance in mathematics education. A preformal proof plays a more important role in mathematics education, because nowadays in mathematics a proof is considered as an important fact from a sociological point of view. A preformal proof was classified into four categories: a) action proof, b) geometric-intuitive proof, c) reality oriented proof, d) proof by generalization from paradiam. An educational significance of a preformal proof are followings: a) A proof is not identified with a formal proof. b) A proof is not only considered from a symbolic level, but also from enactive and iconic level. c) A preformal proof generates a formal proof and convinces pupils of a formal proof d) A preformal proof is psychologically natural. e) A preformal proof changes a conception of what is a proof. Therefore a preformal proof is expected to teach in school mathematics from the elementary school to the secondary school.

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