• 제목/요약/키워드: group action

검색결과 1,576건 처리시간 0.03초

THE TRANSFORMATION GROUPS AND THE ISOMETRY GROUPS

  • Kim, Young-Wook
    • 대한수학회보
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    • 제26권1호
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    • pp.47-52
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    • 1989
  • Methods of Riemannian geometry has played an important role in the study of compact transformation groups. Every effective action of a compact Lie group on a differential manifold leaves a Riemannian metric invariant and the study of such actions reduces to the one involving the group of isometries of a Riemannian metric on the manifold which is, a priori, a Lie group under the compact open topology. Once an action of a compact Lie group is given an invariant metric is easily constructed by the averaging method and the Lie group is naturally imbedded in the group of isometries as a Lie subgroup. But usually this invariant metric has more symmetries than those given by the original action. Therefore the first question one may ask is when one can find a Riemannian metric so that the given action coincides with the action of the full group of isometries. This seems to be a difficult question to answer which depends very much on the orbit structure and the group itself. In this paper we give a sufficient condition that a subgroup action of a compact Lie group has an invariant metric which is not invariant under the full action of the group and figure out some aspects of the action and the orbit structure regarding the invariant Riemannian metric. In fact, according to our results, this is possible if there is a larger transformation group, containing the oringnal action and either having larger orbit somewhere or having exactly the same orbit structure but with an orbit on which a Riemannian metric is ivariant under the orginal action of the group and not under that of the larger one. Recently R. Saerens and W. Zame showed that every compact Lie group can be realized as the full group of isometries of Riemannian metric. [SZ] This answers a question closely related to ours but the situation turns out to be quite different in the two problems.

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우황포용환(牛黃抱龍丸)이 Rat 및 Mouse의 해열(解熱).진통(鎭通) 진경작용(鎭經作用)에 미치는 영향 (Experimental Studies on the Antipyretic, Analgetic, Anticonvulsive effects of the Woo-Whang-Po-Lyong-Whan to Rats and Mice)

  • 원종훈;구본홍
    • 대한한방소아과학회지
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    • 제1권1호
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    • pp.1-12
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    • 1986
  • The Woo-Whang-po-Lyong-Whan has been used as one of the traditional medicines in the field of pediatrics so far since Song dynasty, and still it is widely being used nowadays. It might be considered to be a contribution to do further basic experimental studies on antipyretic, anticonvulsive and analgetic action of the Woo-Whang-po-Lyong-Whan. So it's pharmacological studies were carried out comparing to control drugs. ?Following conclusions were obtained. 1. It's antipyretic action was compared to that of aspirin by Writhing response using acetic acid-method. Mice were given one twentith, one tenth and one fifth tablets of the Woo-Whang-po-Lyong-Whan per Kg of body weight, respecitively. Writhing syndrome frequencies were noted as 38.4 in control group. and $18.0{\pm}12$, $13.17{\pm}2.28$, $7.33{\pm}12$ in above esperimental groups, respectively. In aspirin group it was $18.5{\pm}1.0$ when 2mg aspirin per body weight of mice was given. So it was recognized that antipyretic action of the Woo-Whang-Po-Lyong-Whan become remarkable by increasing amounts of the Woo-Whang-Po-Lyong-Whan. ?2. Antipyretic action in normal temperature mice group was not significant by increasing concentration of the Woo-Whang-Po-Lyong-Whan, but body temperature dropping in normal mice group was slightly noted than control. group, but less temperature dropping was noted than aminopyrin group. ?3. In fever provocated rats groups using Salmonella typhimurium, antipyretic action of the Woo-Whang-Po-Lyong-Whan was not observed significantly than control group. And slight antipyretic action was noted in aminopyrin group. So that antipyretic action of the Woo-Whang-Po-Lyong-Whan was not significant than those of general antipyretic used nowadays, but slower action was recognized. ?4. Anticonvulsive action of the Woo-Whang-Po-Lyong-Whan was studies comparing to that of phenobarbital. Action was not remarkable than phenobarbital, but was significant than control group. No significant intesifying action was noted by increasing amounts of the Woo-Whang-Po- Lyong-Whang.

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The Effects of the Otago Exercise Combined with Action Observation Training on Brain Activity of the Elderly

  • Kim, Jung-hee;Kim, Eun kyong;Lee, Byounghee
    • 대한물리치료과학회지
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    • 제26권3호
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    • pp.1-7
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    • 2019
  • Purpose: The purpose of this study was to investigate the effects of the Otago exercise combined with action observation training on changes of the brain activity of the elderly. Design: Randomized controlled trial. Methods: Thirty elderly women in the experiment were included. Participants were randomly assigned to the Otago combined with action observation training group, the Otago exercise group, and the control group (10 in each group). The Otago combined with action observation training group and the Otago exercise group performed the strength and balance exercises of the Otago exercise program for 50 minutes three times a week for 12 weeks. The Otago combined with action observation training group underwent additional action observation training for the Otago movement for 20 minutes three times a week. No intervention was performed in the control group. PolyG-1 (LAXTHA Inc., Daejeon, Korea) was used to measure the changes in the brain activity following intervention. One-way analysis of variance was used to compare the effects among the groups and a post-hoc test was performed. Results: The relative mu rhythms in the F3, C3, and C4 regions were significantly increased in the Otago combined with action observation training group. Relative beta wave activity in the Fp1, F3, F3, and C3 regions was significantly increased in the Otago combined with action observation training group (p<0.05). Conclusion: The results indicated that the Otago exercise combined with action observation training was effective for promoting the brain activity of the elderly.

동작관찰훈련이 양하지마비 뇌성마비 아동의 뇌활성에 미치는 영향 (The effect of action observation training on brain activity in children with cerebral palsy)

  • 전혜림;정영아;이병희
    • 대한물리치료과학회지
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    • 제27권1호
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    • pp.18-25
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    • 2020
  • Purpose: The purpose of this study was to investigate the improve on brain activity during action observation training for cerebral palsy of diplegia. Design: Randomized controlled trial. Methods: 18 subjects were divide into two groups: action observation training group and a control group. Action observation group practiced repeatedly the action with their motor skill and control group practiced conventional physical therapy. The subjects participated in eighteen 30-min sessions, 3 day a week, for 6week. To confirm the effects on brain activity were evaluated. Results: The results show that the Mu-rhythm was statistically significant increase on the C3 of the action observation training group (p<0.05). Conclusion: The action observation training improves brain activity of a cerebral palsy with diplegia. These results suggest that the action observation training is feasible and beneficial for improving brain activation for the cerebral palsy with diplegia. In the future, I think we need to be actively utilized to the action observation training program in the clinical with the neuromuscular development treatment. And the study on the various the action observation training program that can improve the function of the children with cerebral palsy is thought necessary.

GROUP ACTIONS IN A REGULAR RING

  • HAN, Jun-Cheol
    • 대한수학회보
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    • 제42권4호
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    • pp.807-815
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    • 2005
  • Let R be a ring with identity, X the set of all nonzero, nonunits of Rand G the group of all units of R. We will consider two group actions on X by G, the regular action and the conjugate action. In this paper, by investigating two group actions we can have some results as follows: First, if G is a finitely generated abelian group, then the orbit O(x) under the regular action on X by G is finite for all nilpotents x $\in$ X. Secondly, if F is a field in which 2 is a unit and F $\backslash\;\{0\}$ is a finitley generated abelian group, then F is finite. Finally, if G in a unit-regular ring R is a torsion group and 2 is a unit in R, then the conjugate action on X by G is trivial if and only if G is abelian if and only if R is commutative.

CONTINUOUS SHADOWING AND STABILITY FOR GROUP ACTIONS

  • Kim, Sang Jin
    • 대한수학회지
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    • 제56권1호
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    • pp.53-65
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    • 2019
  • Recently, Chung and Lee [2] introduced the notion of topological stability for a finitely generated group action, and proved a group action version of the Walters's stability theorem. In this paper, we introduce the concepts of continuous shadowing and continuous inverse shadowing of a finitely generated group action on a compact metric space X with respect to various classes of admissible pseudo orbits and study the relationships between topological stability and continuous shadowing and continuous inverse shadowing property of group actions. Moreover, we introduce the notion of structural stability for a finitely generated group action, and we prove that an expansive action on a compact manifold is structurally stable if and only if it is continuous inverse shadowing.

GROUP ACTIONS IN A UNIT-REGULAR RING WITH COMMUTING IDEMPOTENTS

  • Han, Jun-Cheol
    • East Asian mathematical journal
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    • 제25권4호
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    • pp.433-440
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    • 2009
  • Let R be a ring with unity, X the set of all nonzero, nonunits of R and G the group of all units of R. We will consider some group actions on X by G, the left (resp. right) regular action and the conjugate action. In this paper, by investigating these group actions we can have some results as follows: First, if E(R), the set of all nonzero nonunit idempotents of a unit-regular ring R, is commuting, then $o_{\ell}(x)\;=\;o_r(x)$, $o_c(x)\;=\;\{x\}$ for all $x\;{\in}\;X$ where $o_{\ell}(x)$ (resp. $o_r(x)$, $o_c(x)$) is the orbit of x under the left regular (resp. right regular, conjugate) action on X by G and R is abelian regular. Secondly, if R is a unit-regular ring with unity 1 such that G is a cyclic group and $2\;=\;1\;+\;1\;{\in}\;G$, then G is a finite group. Finally, if R is an abelian regular ring such that G is an abelian group, then R is a commutative ring.

GALOIS CORRESPONDENCES FOR SUBFACTORS RELATED TO NORMAL SUBGROUPS

  • Lee, Jung-Rye
    • 대한수학회논문집
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    • 제17권2호
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    • pp.253-260
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    • 2002
  • For an outer action $\alpha$ of a finite group G on a factor M, it was proved that H is a, normal subgroup of G if and only if there exists a finite group F and an outer action $\beta$ of F on the crossed product algebra M $\times$$_{\alpha}$ G = (M $\times$$_{\alpha}$ F. We generalize this to infinite group actions. For an outer action $\alpha$ of a discrete group, we obtain a Galois correspondence for crossed product algebras related to normal subgroups. When $\alpha$ satisfies a certain condition, we also obtain a Galois correspondence for fixed point algebras. Furthermore, for a minimal action $\alpha$ of a compact group G and a closed normal subgroup H, we prove $M^{G}$ = ( $M^{H}$)$^{{beta}(G/H)}$for a minimal action $\beta$ of G/H on $M^{H}$.f G/H on $M^{H}$.TEX> H/.

리듬청각자극을 동반한 동작관찰 신체훈련이 만성 뇌졸중 환자의 하지 근활성도와 보행능력에 미치는 영향 (The Effects of Action Observational Physical Training with Rhythmic Auditory Stimulation on Muscle Activity of the Lower Extremity and Gait Ability in Patients with Chronic Stroke)

  • 송수영;송요한;이현민
    • 대한물리의학회지
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    • 제13권2호
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    • pp.137-145
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    • 2018
  • PURPOSE: The purpose of this study was to investigate the effect of action observational physical training with rhythmic auditory stimulation on muscle activity and gait ability in patients with stroke. METHODS: Twenty-six chronic stroke patients participated in this study were assigned into three groups, experimental group 1 (10% faster tempo rhythmic auditory stimulation with action observation training) n=8, experimental group 2 (average tempo rhythmic auditory stimulation with action observation training) n=9, and control group (action observation training) n=9. In this experiment, the corresponding exercise were applied into the subjects of three group for 30 minute a day, 3 time a week during 4 weeks. All participants were measured to muscle activity of lower limb, 10 meter walking test, Figure of 8 walk test, Dynamic gait Index. The collected data were analyzed by using SPSS (version 18.0 for window) and verified that each data was a normal distribution based on Shapiro-Wilk test. Between-group and within-group comparison was analyzed by using One-way ANOVA test, Paired t-test respectively. In all statistical analyses, significance level, ${\alpha}$ was set by .05. RESULTS: The above results revealed that the all experimental group 1 and experimental group 2 and control group were all effective to improve the lower limb muscle activities, gait ability. However more positive effects shown action observational physical training with rhythmic auditory stimulation experimental group. CONCLUSION: This study suggest that action observation physical training with rhythmic auditory stimulation is effective intervention for improvement of muscle activity and walking ability in chronic stroke patients.

흰쥐의 항염증 및 진통작용에 대한 Glucosamine Hydrochloride와 Taurine 및 그 혼합 투여시의 효과 (Effects of Glucosamine Hydrochloride, Taurine and Their Combined Administration on Anti-inflammatory and Analgesic Action in Rats)

  • 김옥경
    • 한국식품영양과학회지
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    • 제28권5호
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    • pp.1113-1123
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    • 1999
  • The purpose of this study was to see the effect of anti inflammatory and analgesic action of the glucosamine hydrochloride(GA HCl) or taurine. Male Sprague Dawley rats(100~250g) and ICR mice(20 ~30g) were used. Experimental groups were divided into seven groups, one control group given as saline and six groups given as oral administration of GA HCl or taurine; GA HCl 250mg/kg, b.w group, taurine 250mg/kg, b.w group, GA HCl 250mg/kg, b.w+taurine 250mg/kg, b.w group, GA HCl 500mg/kg, b.w group, taurine 500mg/kg, b.w group, GA HCl 500mg/kg, b.w+taurine 500mg/kg, b.w group. Carrageenan induced edema test were shown to be significantly inhibited in the GA HCl 250mg/kg group and taurine 250mg/kg group compared to the control group, but the GA HCl 500mg/kg+taurine 500mg/kg group were significantly inhibited than the control group. Capillary permeability test were shown to be sig nificantly inhibited in the taurine 500mg/kg group, but the GA HCl 500mg/kg+taurine 500mg/kg group were significantly inhibited than the control group. Leucocyte emigration test were shown to be significantly inhibited in the GA HCl 250mg/kg+ taurine 250mg/kg group and GA HCl 500mg/kg+taurine 500mg/kg group compared to the control group. Acetic acid, Phenyl p benzoquinone writhing syndrome were shown to be significantly inhibited in the GA HCl 500mg/kg+taurine 500mg/kg group compared to the control group. Inhibitory action against COX 1 and COX 2 were not significantly inhibited in the experimental group. These results suggest that the combined administration of the GA HCl and taurine have potential action in anti inflammatory and analgesic action.

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