• Journal of applied mathematics & informatics
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• 제29권1_2호
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• pp.517-521
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• 2011

In this paper, we introduce the concepts of m-convex set, mcconvex function and $m^*c$-convex function. We study basic properties for m-convex sets and characterization for such functions.

• East Asian mathematical journal
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• 제39권5호
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• pp.537-547
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• 2023

In this paper, we introduce the optimal approximation by a Gaussian function for a probability density function. We show that the approximation can be obtained by solving a non-linear system of parameters of Gaussian function. Then, to understand the non-normality of the empirical distributions observed in financial markets, we consider the nearly Gaussian function that consists of an optimally approximated Gaussian function and a small periodically oscillating density function. We show that, depending on the parameters of the oscillation, the nearly Gaussian functions can have fairly thick heavy tails.

• 한국건설관리학회논문집
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• 제5권6호
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• pp.63-71
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• 2004

설계VE 활동작업 중 대상의 기능을 철저하게 분석할 수 있는 기능분석 활동은 그 중요성에도 불구하고 수행자의 인식부족, 분석방법에 대한 어려움 및 설계VE 활동 시간적 제약 등의 이유로 활동 자체가 약화, 변형되거나, 생략되는 경우가 발생하고 있다. 이와 같이 기능분석이 변형된 VE활동은 아이디어 창출과정에 있어서 기능부분이 약화된채 아이디어의 결과를 창출함으로 신뢰성이 매우 떨어진다고 할 수 있다. 따라서 본 연구는 현재 시행되어진 설계VE작업중 기능분석활동 부분을 분석하여 이를 활동유형별로 분류, 그 특징을 파악한다. 이를 통해 기능분석 활동에 대한 올바른 이해를 확립하고, 기능분석 활동의 개선부분을 도출하여 올바른 설계VE 활동을 유도하고자 한다.

• 한국컴퓨터정보학회논문지
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• 제17권12호
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• pp.149-158
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• 2012

본 논문에서는 점근적으로 최적인 두가지의 무작위화 함수인 일라이어스(Elias) 함수와 페레즈(Peres) 함수의 장단점을 고려한 하이브리드 무작위화 함수를 제안한다. 무작위화 함수는 편향성이 있는 무작위수의 공급원으로부터 균등한 무작위수를 생성하는데 쓰이는 알고리즘을 수학적으로 추상화한 것이다. 일라이어스 함수와 페레즈 함수는 입력의 길이가 무한으로 증가함에 따라 그 출력효율성이 정보론적 한계치에 다가간다. 특히, 일라이어스 함수는 주어진 (유한의) 입력길이에 대해 최적인 무작위화 함수이다. 그러나 그 계산은 간단하지 않고, 주어진 입력길이에 의존한다. 반면, 페레즈 함수는 정해진 입력의 길이에 대해 출력효율이 최적이지는 않으나, 점근적으로는 최적이고, 간단한 재귀식에 의해 정의되어서 그 계산이 매우 간단하고 적은 메모리를 필요로 한다. 이러한 계산복잡도와 출력효율에 대한 두가지 무작위화 함수의 장단점에 주목하여, 각각의 장점을 고려한 하이브리드 무작위화 함수를 제안하고 이를 분석한다.

• 치위생과학회지
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• 제17권5호
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• pp.454-461
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• 2017

The purpose of this study was to confirm the relevance of dental health capacity and pulmonary function status. The subjects of this study were adults aged 40 years and older, who participated in pulmonary function and oral examinations. The data used for this study were raw data from the sixth Korea National Health and Nutrition Examination Survey (2013~2015). Statistical analysis was performed by analysis of complex sample survey data. The results were as follows: First, restrictive and obstructive patterns were more prevalent among males than females. They were even worse in older subjects. Approximately 67% of smokers had obstructive pattern. Second, there was a relevance between dental health capacity and pulmonary function status. The functioning teeth index, number of present teeth, and number of sound teeth (ST), which are indicators of dental health, declined with decreased pulmonary function. The number of missing teeth (MT) increased as the pulmonary function deteriorated (p<0.05). Third, the relevance between dental health capacity and pulmonary function status after stratifying the life-long smoking experience was statistically significant in the tissue health (T-health) index and ST among non-smokers. The relevance between dental health capacity and pulmonary function status after stratifying the life-long smoking experience was statistically significant (p<0.05) for the T-health index, ST, and MT among smokers. However, there was no relevance between dental health capacity and pulmonary function status after stratifying the life-long smoking experience and adjusting confounding variables. In conclusion, there was a relevance between dental health capacity and pulmonary function status after confounding variables were adjusted. However, there was no relevance between dental health capacity and pulmonary function status after stratifying the life-long smoking experience and adjusting confounding variables.

• 종양간호연구
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• 제12권2호
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• pp.156-165
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• 2012

Purpose: This study was to identify predictors of sexual function in gynecologic cancer patients. Methods: The participants were 154 patients treated at a university medical center in A city, Korea. The data collection was performed through a structured questionnaire from July to December, 2010. The instruments used in this study were Female Sexual Function Index (FSFI) perceived health status scale, Eastern Cooperative Oncology Group (ECOG) performance status, body image, and depression. Data were analyzed using descriptive statistics, Mann-Whitney test, Kruskal-Wallis test and stepwise multiple regression with the SPSS 18.0. Results: The mean score of perceived health status was 8.42 and sexual function was 8.42. The lowest score among sexual function was lubrication. The scores of sexual function was significantly different by age, job, marital status, period after diagnosis of cancer and diagnosis. There were significant correlations between sexual function, perceived health status, ECOG performance, body image and depression. In multiple regression analysis, predictors were identified as ECOG performance, age, diagnosis and period after diagnosis of cancer (Adj.$R^2$=.28). The most powerful predictor of female sexual function was ECOG performance (19.0%). Conclusion: The above findings indicate that it is necessary to develop a more effective and personalized sexual function improvement program for gynecologic cancer patient.

• 대한물리의학회지
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• 제7권3호
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• pp.267-274
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• 2012

Purpose : The purpose of this study was to investigate characteristics of the forced pulmonary function test effect by changes in lung function related to postures and by Transverse Abdominis(TrA). Contraction in standing position during forced inspiration and expiration with young female adults. Methods : 10 young female adults were recruited this study. pulmonary Function test was measured with a Master-screen Body (VIASYS Inc., CA, 미국). To check the changes in lung function with different postures, we tested pulmonary function in the standing and supine position each. In the standing position, while the transversus abdominis was activating, we compared the forced inspiration with the forced expiration. Statistical analysis was used Independent t-test to know difference between forced inspiration and expiration of activated TrA. Results : According to the study, the change of pulmonary function were statistically significant difference in the standing compared to the supine position. The contraction of the transversus abdominis causes decrease in the change of forced inspiration and increase in the change of forced expiration. Conclusion : These results indicate that spontaneous contraction of the TrA in standing position helps pulmonary function. And the selective contraction of the transversus abdominis at the end of forced inspiration makes increases in the forced expiration.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.1060-1065
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• 1990

In general it is difficult to determine a Liapunov function for a given asymptotically stable, nonlinear differential equations system. But, in the system with control inputs, it is feasible to make a given positive function, except for a small area, globally satisfy the conditions of the Liapunov function for the system. We call such a positive function a Liapunov-like function, and propose a method of nonlinear optimal regulator using this Liapunov-like function. We also use the periodic Liapuitov-like friction that suits the system whose equilibrium points exist periodically. The relationship between the Liapunov function and cost function which this nonlinear regulator minimizes is considered using inverse optimal method.

• 대한수학회논문집
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• 제36권4호
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• pp.743-757
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• 2021

We consider a different version of Schwarz Lemma for λ-spirallike function of complex order at the boundary of the unit disc D. We estimate the modulus of the angular derivative of the function $\frac{zf^{\prime}(z)}{f(z)}$ from below for λ-spirallike function f(z) of complex order at the boundary of the unit disc D by taking into account the zeros of the function f(z)-z which are different from zero. We also estimate the same function with the second derivatives of the function f at the points z = 0 and z = z₀ ≠ 0. We show the sharpness of these estimates and present examples.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(1)
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• pp.217-220
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• 2000

This paper studies a real-time VBR traffic characterization. There are two big approaches to determine traffic. One is a statistic approach and the other is a deterministic approach. This paper proposes a new constraint function, what we called “Sub-Sum Constraint Function”(SSCF). This function is mainly based on a deterministic approach and uses a statistic approach. It predicts and calculates the next rate with a present information about the stream. SSCF captures the intuitive bounded by a rate lower than its peak rate and closer to its long-term average rate. This model makes a order of the constraint function much less than any other works (O(n)). It can also be mapped on a token bucket algorithm which consists of r (token rate) and b (token depth). We use a concept, EB(effective bandwidth) for a utility of our function and comparing with other techniques such as CBR, average VBR. We simulated 21 multimedia sources for verifying the utility of our function.