• 제목/요약/키워드: central point

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Chandra Archival Survey of Galaxy Clusters: X-ray Point Sources in Cool-core and Non-cool-core Clusters

  • 김민선;김은혁
    • 천문학회보
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    • 제37권2호
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    • pp.78.1-78.1
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    • 2012
  • We have studied the physical properties of X-ray point sources in galaxy clusters using ~600 Chandra archival observations. The goal of this study is to investigate the density environmental effects on the physical properties of X-ray point sources by comparing the properties of X-ray point sources in galaxy clusters to those in typical blank fields. In this presentation, we show the nature of X-ray point sources which are expected to be related with galaxy clusters with different core properties. Using ~60 galaxy clusters observed with Chandra, we investigate the physical properties of X-ray point sources in cool-core and non-cool-core clusters. The cool-core clusters are known to have short central cooling time, and are characterized by low central entropy, systematic central temperature drops, and a brightest cluster galaxy at the X-ray peak. While the non-cool-core clusters have longer central cooling time, and are characterized by large central entropies and flat or centrally rising temperature profile. We show that how central core properties of galaxy clusters affect on the physical properties of X-ray point sources.

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간호대학생의 자아상태와 대응양상과의 관계 연구 (Study on the Ego states and Coping Style of Nursing Students)

  • 원정숙
    • 여성건강간호학회지
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    • 제8권4호
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    • pp.608-618
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    • 2002
  • The purpose of this study is to analyze the type of ego states and stress coping style on female college students who are in the course of nursing study. This study is performed in the view of Transactional Analysis and designed to scrutinize descriptive correlations between the type of ego states and stress coping style. The subject is consists of 144 freshmen and sophomore, 138 junior and senior students group, who are students of K nursing college located in Seoul. The sampling investigation period is on Sept. 14, 2002 to Oct. 26, 2002. The measuring instrument used for Transactional Analysis ego state is 50 items Ego-gram research paper devised by Dusay(1997). For studying coping style, Folkman & Lazarus's measurement(1984) was adopted, which is translated and modified by Han, and Oh,(1990). Statistic average and standard deviation were generated by using SPSS PC+, t-test and Pearson correlation. The results were as follows: 1) In the type of ego states on both groups(lower group : freshmen, sophomore upper group : junior, senior) indicated the arithmetic apex NP(maximum value), then the point A was high and the data made a down slope to point AC. In the comparison to type of ego states between two groups, only at point CP, the data value of upper year students represented higher than that of lower year ones by C(t=2.28, p=.023). In the psychological energy level of ego states, both groups indicated average level.2) Stress coping style of whole students were highly and affirmatively dedicated to research. Consecutive consequences follow like this(high to low) : the central point of problem, search for social support, hopeful aspect and indifference. Especially hopeful aspect(t=.67, p=.05), relaxation of tension(t=-2.16, p=.03) made significant difference each other in the view of arithmetic calculation 3) While verifying coping style in terms of ego states level between lower and upper students group, In type CP, high level ego states group indicated significant difference on stress coping style area than low leveled group and made such sequences as the central point of problem, hopeful aspect, search for social support, positive interest and relaxation of tension. In type NP, sequences such as the central point of problem, search for social support, positive interest and relaxation of tension were emerged with little differences. In type A, the central point of problem, positive interest and relaxation of tension. In type FC, hopeful aspect, search for social support, positive interest and relaxation of tension. In type AC, hopeful aspect and indifference were derived significantly different(p<.05). 4) In the aspect of relation between ego states and coping style, type CP presented the central point of problem and relaxation of tension, type NP presented positive interest, search for social support and the central point of problem, type A showed the central point of problem, positive interest and relaxation of tension, type FC showed relaxation of tension, positive interest, search for social support, indifference and the central point of problem, type AC showed hopeful aspect, indifference and the central point of problem. All the sequence shown above had high-to-low procedure and represented static relations each other(p<.05).

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Maximum Degree Vertex Central Located Algorithm for Bandwidth Minimization Problem

  • Lee, Sang-Un
    • 한국컴퓨터정보학회논문지
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    • 제20권7호
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    • pp.41-47
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    • 2015
  • The bandwidth minimization problem (BMP) has been classified as NP-complete because the polynomial time algorithm to find the optimal solution has been unknown yet. This paper suggests polynomial time heuristic algorithm is to find the solution of bandwidth minimization problem. To find the minimum bandwidth ${\phi}^*=_{min}{\phi}(G)$, ${\phi}(G)=_{max}\{{\mid}f(v_i)-f(v_j):v_i,v_j{\in}E\}$ for given graph G=(V,E), m=|V|,n=|E|, the proposed algorithm sets the maximum degree vertex $v_i$ in graph G into global central point (GCP), and labels the median value ${\lceil}m+1/2{\rceil}$ between [1,m] range. The graph G is partitioned into subgroup, the maximum degree vertex in each subgroup is set to local central point (LCP), and we adjust the label of LCP per each subgroup as possible as minimum distance from GCP. The proposed algorithm requires O(mn) time complexity for label to all of vertices. For various twelve graph, the proposed algorithm can be obtains the same result as known optimal solution. For one graph, the proposed algorithm can be improve on known solution.

FIXED POINT THEOREMS FOR CONDENSING MAPPINGS SATISFYING LERAY-SCHAUDER TYPE CONDITIONS

  • Pulickakunnel, Shaini;Valappil, Sreya Valiya
    • 대한수학회논문집
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    • 제31권1호
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    • pp.139-145
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    • 2016
  • In this paper, some new fixed point theorems for condensing mappings are established based on a well known result of Petryshyn. We use several Leray-Schauder type conditions to prove new fixed point results. We also obtain generalizations of Altman's theorem and Petryshyn's theorem as well.

Evolutionary Operation-Factorial Design Technique를 이용한 곤약의 항균활성 최적화 (Optimization for the Antibacterial Activity of Konjak Jelly using Evolutionary Operation-Factorial Design Technique)

  • 이난희;최원석;최웅규
    • 한국식품영양학회지
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    • 제31권2호
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    • pp.272-277
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    • 2018
  • This research was conducted to elucidate the optimum conditions for the antibacterial activity of konjak jelly using the evolutionary operation-factorial design technique. In the first set of experiments, concentration of a coagulation agent, soaking liquid, and temperature of water were set to 0.4%, $0.6{\times}10^{-2}N$, and $65^{\circ}C$ as a central point, respectively. The highest antibacterial activity was acquired at E21, in which the number of bacteria was 1.25 log cfu/g. Because the code of changes in the main effect was (-), it could be decided that the central point of the first set was not the optimum point. Although antibacterial activity in the second set was improved, the values of the main effect were higher than that of changes in the mean effect. The central point of third set was concentration of coagulation agent 0.8%, concentration of soaking liquid $1.0{\times}10^{-2}N$, and temperature of water $65^{\circ}C$. It was found that the antibacterial activity of central point in the third set was highest among all the tested set. Further, all the necessary conditions were appropriate to reach the optimum condition. The antibacterial activity of the central point in third set was more than 1,000 times higher than that of E11, in first set.

Delay-dependent Stabilization of Singular Systems with Multiple Internal and External Incommensurate Constant Point Delays

  • Xie, Yong-Fang;Gui, Wei-Hua;Jiang, Zhao-Hui
    • International Journal of Control, Automation, and Systems
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    • 제6권4호
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    • pp.515-525
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    • 2008
  • In this paper, the problem of delay-dependent stabilization for singular systems with multiple internal and external incommensurate constant point delays is investigated. The condition when a singular system subject to point delays is regular independent of time delays is given and it can be easily test with numerical or algebraic methods. Based on Lyapunov-Krasovskii functional approach and the descriptor integral-inequality lemma, a sufficient condition for delay-dependent stability is obtained. The main idea is to design multiple memoryless state feedback control laws such that the resulting closed-loop system is regular independent of time delays, impulse free, and asymptotically stable via solving a strict linear matrix inequality (LMI) problem. An explicit expression for the desired memoryless state feedback control laws is also given. Finally, a numerical example illustrates the effectiveness and the availability for the proposed method.

Characterization of the Functional Domains of Human Foamy Virus Integrase Using Chimeric Integrases

  • Lee, Hak Sung;Kang, Seung Yi;Shin, Cha-Gyun
    • Molecules and Cells
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    • 제19권2호
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    • pp.246-255
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    • 2005
  • Retroviral integrases insert viral DNA into target DNA. In this process they recognize their own DNA specifically via functional domains. In order to analyze these functional domains, we constructed six chimeric integrases by swapping domains between HIV-1 and HFV integrases, and two point mutants of HFV integrase. Chimeric integrases with the central domain of HIV-1 integrase had strand transfer and disintegration activities, in agreement with the idea that the central domain determines viral DNA specificity and has catalytic activity. On the other hand, chimeric integrases with the central domain of HFV integrase did not have any enzymatic activity apart from FFH that had weak disintegration activity, suggesting that the central domain of HFV integrase was defective catalytically or structurally. However, these inactive chimeras were efficiently complemented by the point mutants (D164A and E200A) of HFV integrase, indicating that the central domain of HFV integrase possesses potential enzymatic activity but is not able to recognize viral or target DNA without the help of its homologous N-terminal and C-terminal domains.

두 점 교정법을 이용한 담배 연기 성분 중 니코틴 분석 결과에 대한 불확도 평가 (Uncertainty Evaluation of Nicotine in Cigarette Mainstream Smoke Using Two Point Re-calibration Method)

  • 김미주;지상운;황건중;이문수;조성일
    • 한국연초학회지
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    • 제26권2호
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    • pp.168-178
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    • 2004
  • Uncertainty of final measurement results considering main uncertainty sources being in nicotine of mainstream smoke was estimated. This study was accomplished by using the ISO 'The Guide to the Expression of Uncertainty in Measurement'. Using the two point re-calibration method, uncertainty for nicotine concentration was calculated considering the uncertainty sources of each step. The concentration and uncertainty of nicotine in mainstream smoke was estimated as $153.95{\pm}17.84\;{\mu}g/mL\;(0.77\pm0.089 mg/cig)$. The expanded uncertainty was $17.84 {\mu}g/mL(\pm0.089 mg/cig).$ The reported expanded uncertainty of the measurement is stated as the standard uncertainty of measurement multiplied by a coverage factor of 2, which for a normal distribution corresponds to a coverage probability of approximately $95\%$ The former expression indicates the conversion concentration into the sample.

POSITIVE SOLUTIONS OF THE SECOND-ORDER SYSTEM OF DIFFERENTIAL EQUATIONS IN BANACH SPACES

  • Cao, Jianxin;Chen, Haibo;Deng, Jin
    • Journal of applied mathematics & informatics
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    • 제28권5_6호
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    • pp.1445-1460
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    • 2010
  • In this paper, a second-order system of multi-point boundary value problems in Banach spaces is investigated. Based on a specially constructed cone and the fixed point theorem of strict-set-contraction operators, the criterion of the existence and multiplicity of positive solutions are established. And two examples demonstrating the theoretic results are given.

담배 연기 중 휘발성 유기물질 분석에 대한 측정 불확도 산출 (Measurement Uncertainty for Analysis of Volatile Organic Compound in Cigarette Mainstream Smoke)

  • 가미현;조성일;김미주;이철희;지상운;정종수;김용하;민영근
    • 한국연초학회지
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    • 제28권2호
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    • pp.144-151
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    • 2006
  • A measurement uncertainty for analysis of volatile organic compound (benzene) in cigarette mainstream smoke was carried out. In this study one point re-calibration method was used to estimate uncertainty for benzene. The measurement uncertainty was calculated based on the uncertainty sources of each analysis step, quality appraisal sources, drift and repeatability. As a result, the concentration and expanded uncertainty of benzene in cigarette mainstream smoke were measured as $38.08{\pm}4.36{\mu}g/cig$. Relative uncertainty of drift and repeatability obtained were 5% and 3%, respectively.