• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 D
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• pp.2564-2566
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• 2005

This paper presents an iterative linear matrix inequality (LMI) method for $H_2$ and $H_{\infty}$ optimal static output feedback (SOF) control, which is expressed in terms of LMIs subject to an additional rank condition. We propose a linear Penalty function to penalize the rank constraint so that static $H_2$ and $H_{\infty}$ synthesis results in solving a series of convex LMI optimization problems. Numerical experiments for various $H_2$ and $H_{\infty}$ SOF synthesis were performed to demonstrate the effectiveness of the proposed algorithm.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 D
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• pp.2242-2244
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• 2004

This paper deals with the design of a reduced-order stabilizing controller for the linear system. The coupled lineal matrix inequality (LMI) problem subject to a rank condition is solved by a sequential semidefinite programming (SDP) approach. The nonconvex rank constraint is incorporated into a strictly linear penalty function, and the computation of the gradient and Hessian function for the Newton method is not required. The penalty factor and related term are updated iteratively. Therefore the overall procedure leads to a successive LMI relaxation method. Extensive numerical experiments illustrate the proposed algorithm.

• 여성건강간호학회지
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• 제1권1호
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• pp.138-152
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• 1995

The condition of nutrition during infancy will greatly affect infants' physical, emotional growth, especially breast feeding is important in their growth and development, and emotional stability, too. Despite such advantages of breast-feeding, its rate has continued to fall year after year in Korea : the 95% rate in 1960's has fallen to 25.4% in 1990. It is known that such a downfall of breast-feeding rate is associated with various factors. The purpose of the study is to examine mother's and nurses' in nursery perception of the impediment factors of breast-feeding : to compare those between of breast-feeding : to compare those between two groups : to provide fundamental data for developing strategies for increasing breast-feeding. The subjects were 45 new mothers from one hospital and the same number of nurses sampled from 3 university hospitals, in Seoul. The data were collected for 11 days from April 12 to April 23, 1994 and a questionnaire was developed based on the interview with 14 nurses and 10 mothers and the literature reviews. Liker's Five-Point Scale was used as measurement. The Data were analyzed using SPSS / PC and descriptive statistics, t-test, ANOVA. The results of study are as follows : 1) Most new mothers get the information about breast-feeding from their mothers, books or newspaper, and relatives in rank than professionals(nurses or doctors). 2) The impediment factors the breast-feeding are categorized as mothers, hospital system, medical personnels and social factors. The most frequently mentioned impediment factors from mothers are 'Difficulty by operational wounds'(3.13), 'Lack of will for breast-feeding'(3.47), 'Insufficient rest and sleep'(3.52) and 'Opposition from husband or his family members'(4.77)in rank. On the other hand those factors from nurses are 'Inadequate nipple condition'(2.37), 'Decreasing milk secretion given medicine after operation'(2.63), 'Mothers knowledge deficit by poorly prepared education'(2.79) and 'Mothers abhorance of breast-feeing'(3.87) in rank. 3) As for the hospital system, the highly perceived impediment factors by mothers are 'Seperation of baby from mother after birth'(2.78), 'Lack of space for breast-feeding in the hospital'(2.93), 'Lack of facility for informing the time for breast-feeding'(3.18) and 'Because of babys' preference artificial nipple by being accustomed to it in hospital(3.97), in rank. Meanwhile, those from nurses are "Seperation of baby from mother after birth",(1.92), "Inconsistency between hospital's nursing time and mother's breast secretion time" scretion time(2.97), "Lack of space for breast-feeding in the hospital"(3.39), and "Lack of facility for informing the time for breast-feeding"(3.74) 4) As for the medical personnels, the highestly perceived Impediment factor from mothers in "Lack of professional nurses for breast-feeding"(2.96), and the lowestly perceived one is "Doctors' reluctance"(4.75). Nurses perceived same as mothers, too. 5) As for the social factors, the highestly perceived impediment factor by mothers and nurses is "Inconvience of social activities"(2.83) and the lowestly ones are "The sense of self-sacrifice"(4.22) by mothers, and "The sense of old fashioned"(4.13) by nurses. 6) The difference of the perception of impediment factors between mothers and nurses is statistically significant only in mother factor.

• Journal of applied mathematics & informatics
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• 제20권1_2호
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• pp.35-59
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• 2006

In this paper, we generalized the results of [23, 26], and get the results of the condition number of the W-weighted Drazin-inverse solution of linear system W AW\chi=b, where A is an $m{\times}n$ rank-deficient matrix and the index of A W is $k_1$, the index of W A is $k_2$, b is a real vector of size n in the range of $(WA)^{k_2}$, $\chi$ is a real vector of size m in the range of $(AW)^{k_1}$. Let $\alpha$ and $\beta$ be two positive real numbers, when we consider the weighted Frobenius norm $\|[{\alpha}W\;AW,\;{\beta}b]\|$(equation omitted) on the data we get the formula of condition number of the W-weighted Drazin-inverse solution of linear system. For the normwise condition number, the sensitivity of the relative condition number itself is studied, and the componentwise perturbation is also investigated.

• The Journal of Korean Physical Therapy
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• 제33권3호
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• pp.162-167
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• 2021

Purpose: A hyperextended knee is described as knee pain associated with an impaired knee extensor mechanism. Additionally, a hyperextended knee may involve reduced position sense of the knee joint that decreases the individual's ability to control end-range knee extension movement. The purpose of this study was to investigate the effects of visual biofeedback information for plantar pressure distribution on knee joint angle and lower extremity muscle activities in participants with hyperextended knees. Methods: Twenty-three participants with hyperextended knees were recruited for the study. Surface electromyography signals were recorded for the biceps femoris, rectus femoris, gastrocnemius, and tibialis anterior muscle activities. The plantar pressure distribution was displayed and measured using a pressure distribution measuring plate. Knee joint angle kinematic parameters were recorded using a motion analysis system. The visual biofeedback condition was the point at which the difference between the forefoot and backfoot plantar foot pressure on the monitor was minimized. The Wilcoxon signed-rank test was used to determine the significance between the visual biofeedback condition and the preferred condition. Results: The knee joint angle was significantly decreased in the visual biofeedback condition compared to that in the preferred condition (p<0.05). The rectus femoris and gastrocnemius muscle activities were significantly different between the visual biofeedback and preferred conditions (p<0.05). Conclusion: The results of this study showed that visual biofeedback of information about plantar pressure distribution is effective for correcting hyperextended knees.

• 대한수학회보
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• 제51권4호
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• pp.1101-1113
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• 2014

We give analogous criterion to admit a real parabolic connection on real parabolic bundles over a real curve. As an application of this criterion, if real curve has a real point, then we proved that a real vector bundle E of rank r and degree d with gcd(r, d) = 1 is real indecomposable if and only if it admits a real logarithmic connection singular exactly over one point with residue given as multiplication by $-\frac{d}{r}$. We also give an equivalent condition for real indecomposable vector bundle in the case when real curve has no real points.

• Korean Journal of Mathematics
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• 제12권2호
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• pp.201-209
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• 2004

We define the incidence matrices of oriented and nonoriented ${\kappa}$-hypergraphs, respectively. We discuss the ranks of some circulant matrices and show that the rank of the incidence matrices of oriented and nonoriented ${\kappa}$-hypergraphs H are $n$ under a certain condition on the ${\kappa}$-edge set or ${\kappa}$-arc set of H.

• 대한수학회논문집
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• 제15권3호
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• pp.521-531
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• 2000

Graph C*-algebras C*(E) are the universal C*-algebras generated by partial isometries satisfying the Cuntz-Krieger relations determined by directed graphs E, and it is known that a simple graph C*-algebra is extremally rich in sense that it contains enough extreme consider a sufficient condition on a graph for which the associated graph algebra(possibly nonsimple) is extremally rich. We also present examples of nonextremally rich prime graph C*-algebras with finitely many ideals and with real rank zero.

• 대한임베디드공학회논문지
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• 제18권6호
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• pp.311-317
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• 2023

This paper presents a sliding mode observer (SMO) for reconstructing cyber attacks affecting a system. The system is first re-expressed such that its design freedom is easier to manipulate. The SMO is then used to reconstruct the cyber attack affecting the system. A simulation example is used to verify the performance of the SMO under two types of cyber attacks, and its results demonstrate the effectiveness of our proposed scheme.

• 한국항만경제학회지
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• 제24권4호
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• pp.313-327
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• 2008

한국과 일본은 가장 가까운 이웃 나라이면서 한국은 일본의 식민지를 거친 경험을 갖고 있는 논문에서는 Liu(2008)의 슬랙변수모형을 도입하여 이론적으로 설명하고 1994년 및 1995년의 국내 20개 항만의 3개의 산출물(수출입물량, 선박입출항척수, 항만재정수입)과 2개의 투입물(접안능력, 하역능력)을 이용하여 국내항만들의 효율성을 측정한 후에, 양년도간에 모두 효율적인 항만으로 판명된 항만을 제외한 나머지 16개 항만들의 효율성 순위를 이용하여 월콕슨의 부호순위검정을 통해서 슬랙변수모형이 갖고 있는 항만효율성측면의 예측력을 측정하는 방법을 보여 주었다. 또한 동일한 방법으로 다년도(1995년-2003년)분석을 실시하여 항만효율성의 예측력은 어느 정도 되는지를 검정하였다. 다년도(1995-2003년)의 실증분석의 주요한 결과를 요약한다면 "가설검정의 모든 결과는 귀무가설을 기각할 수 없는 것"으로 나타났다. 즉, 예측자료와 실제자료의 차이가 있다고 할 수 없기 때문에, 예측자료가 실제자료를 반영하고 있는 것으로 나타났다. 특히 2000-2001년, 2003-2004년의 유의수준은 60%에 가까운 수준으로 나타나서 예측력이 있는 것으로 나타났으나 1995-1996년, 2002-2003년의 예측력은 낮은 것으로 나타났다. 본 연구의 정책적인 함의는 국내항만들도 슬랙변수모형과 월콕슨부호순위검정방법을 이용하여 차년도의 효율성, 또는 경영성과를 예측하여 제시하는 것도 항만의 효율성을 높일 수 있는 한 가지 방법이 될 수 있다는 점이다.