On sufficient conditions for Carath\'eodory functions with the fixed second coefficient

OhSang Kwon 호남수학회 2019 호남수학학술지 Vol.41 No.2

In the present paper, we derive several sufficient conditions for Carath\'eodory functions in the open unit disk $\mathbb{D} := \1\{ z\in\mathbb{C} : |z|<1 \2\}$ under the constraint that the second coefficient of the function is preassigned. And, we obtain some sufficient conditions for strongly starlike functions in $\mathbb{D}$.

Development of Hair Follicle-on-a-chip for Evaluating Hair Growth Promoting Compound

( Ohsang Kwon ) 한국피부장벽학회 2021 한국피부장벽학회지 Vol.23 No.2

Alopecia, in numerous pathological cases, arises due to an inadequate hair follicle (HF) stem cell activation or proliferation, resulting in telogen phase prolongation during the hair cycle. Increasing therapeutic and cosmetic demands for the alleviation of alopecia has driven research into the discovery or synthesis of novel compounds that can promote hair growth, which mirrored by HF stem cell activation or proliferation, to initiate the anagen phase. Although several methods for evaluating the hair growth-promoting effects of candidate compounds are being used, many of these methods are difficult to employ for the large-scale simultaneous screening of various compounds. Herein, we would like to introduce a simple and reliable in vitro assay method for the simultaneous screening of hair growth-promoting effects of candidate compounds in a large scale. The advantages of this type of assays will be i) it is physiologically and practically advantageous as it uses 3D cultured two-type human cells which are easily available; ii) it is simple as it uses length as the only endpoint; and iii) the presence of a high throughput system, which screens various compounds simultaneously. In conclusion, the assay could serve as an easy and reliable method to validate hair growth-promoting effect of a large volume of library molecules.

The Two-Commnunities Metaphor and Knowledge Utilization : From Organizational Change Perspectives 조직의 계획적변화 관점에서

Kwon, Ohsang,Kim, Jongsup 嶺南大學校附設 社會科學硏究所 1992 社會科學硏究 Vol.12 No.1

International Equity Investment and its Currency Hedging by Foreign Exchange Forward Contract over Finite Periods

Ohsang Kwon 한국재무학회 2011 한국재무학회 학술대회 Vol.2011 No.05

This paper studies the issues related to finite-period overseas investment, foreign exchange rate, and currency hedging by foreign exchange forward contract. It is demonstrated that foreign exchange rate should be as important as foreign asset as far as overseas investment decision is concerned and that the decision ought to be made by considering the two factors conjunctionally, rather than separately. In contrast to a common perception, foreign exchange forward is inadequate to deal with currency hedging in many actual situations, due to its notional mismatch, costly forward point, and implicit leverage in it. It is shown that correlation coefficient between financial variables like foreign asset and foreign exchange rate can be insufficient and even misleading in describing the eventual association between them thus a new empirical statistic is proposed to supplement correlation. Empirical results are presented for the equity market investment into three developed and four emerging market countries from Korean and the US investors’ standpoints.

Uncertainty, View, and Hedging: Optimal Choice of Instrument and Strike for Value Maximization

Ohsang Kwon 한국경영과학회 2011 Management Science and Financial Engineering Vol.17 No.2

This paper analytically studies how to choose hedging instrument for firms with steady operating cash flows from value maximization perspective. I derive a formula to determine option’s optimal strike that makes hedged cash flow have the best monetary payoff given a hedger’s view on the underlying asset. I find that not only the expected mean but also the expected standard deviation of the underlying asset in relation to the forward price and the implied volatility play a crucial role in making optimal hedging decision. Higher moments play a certain part in hedging decision but to a lesser degree.

STARLIKENESS AND SCHWARZIAN DERIVATIVES OF HIGHER ORDER OF ANALYTIC FUNCTIONS

Kwon, Ohsang,Sim, Youngjae Korean Mathematical Society 2017 대한수학회논문집 Vol.32 No.1

In this paper we apply the third-order differential subordination results to normalized analytic functions in the open unit disk. We obtain appropriate classes of admissible functions and find some sufficient conditions of functions to be starlike associated with Tamanoi's Schwarzian derivative of third order. Several interesting examples are also discussed.

A CERTAIN SUBCLASS OF JANOWSKI TYPE FUNCTIONS ASSOCIATED WITH κ-SYMMETRIC POINTS

Kwon, Ohsang,Sim, Youngjae Korean Mathematical Society 2013 대한수학회논문집 Vol.28 No.1

We introduce a subclass $S_s^{({\kappa})}$(A,B) (-1 ${\leq}$ B < A ${\leq}$ 1) of functions which are analytic in the open unit disk and close-to-convex with respect to ${\kappa}$-symmetric points. We give some coefficient inequalities, integral representations and invariance properties of functions belonging to this class.

지역균형발전과 예산

권오상(Kwon Ohsang) 한국지역사회학회 2006 지역사회연구 Vol.14 No.2

The balanced development of the country and decentralization have been key words of President Noh's government. Centralized development and concentration of population and public offices in Seoul and vicinities have brought inequal development and underdevelopment of other regions in Korea. To solve such problems the government passed a law of three decentralization special laws and has established The Presidential Committee on Balanced National Development. The committee has initiated a lot of policy initiatives such as moving national capital to local regions, constructing the Innovation City a province or metro city by relocating government offices to IC. Among many successful policies by PCBND, most distinguishing one is setting up a Special Account on Balanced Development(SABD). The budget gave discretional rights of local government on how to use the money. However, SABD asks equal amount of matching funds for national government expenditure regardless of financial independence rate. Secondly, there is no explicit rules of distribution of SABD money of provincial or metro governments when they redistribute it to county or district governments. Thirdly, strategic industries of local governments and input of SABD money do not match. Even if there are many problems of SABD budget to solve, still it is much better and helpful of local government than ever before.

토픽맵을 이용한 e-Learning 모델에 관한 연구

권오상(Ohsang Kwon),문석재(Moon S.J.),엄영현(Eum Y.H.),국윤규(Kook Y.G.),정계동(Jung K.D),최영근(Choi Y.K.) 한국정보과학회 2006 한국정보과학회 학술발표논문집 Vol.33 No.2D

e-Learning 분야는 정부, 기업, 학교 등 많은 조직에서 교육을 위한 수단으로 사용되어지고 있다. 이러한 e-Learning은 독립적인 운영플렛폼의 개발부터 웹 기반의 코스웨어(Courseware)까지 발전해왔다. 코스웨어는 컴퓨터 전달 체제를 통하여 교수-학습 과정을 촉진시켜 명시된 교수 목표 하에 학습자의 지식과 기능의 바람직한 변화를 목적으로 설계 및 개발된 교육용 소프트웨어와 데이터라고 할 수 있다. 또한 컴퓨터 언어 및 저작도구(Authoring Tools)를 이용하여 각 과목별 교육내용을 음성, 그림, 애니메이션, 동영상 등의 다양한 형태로 제시될 수 있도록 저작된 프로그램으로 주로 눈으로 보고 귀로 들으면서 학습하는 유형이다. 현재 코스웨어에서 제공되는 정보는 학습에 대한 정보와 교수정보 그리고 Client의 학습 진행상황 등을 제공한다. 하지만 학습에 연관된 다른 학습이나 학습에 관련된 교수들의 전공정보, 또한 학습에 관련된 어플리케이션 등을 검색하려 할 때는 하나하나 따로 검색을 해야 하는 어려움이 따른다. 본 논문에서는 이러한 문제점을 해결하기 위하여 학습에 대한 목적과 관련학습, 관련교수, 관련연구, 관련 어플리케이션 등의 연관성을 토픽맵(TopicMap)을 이용하여 학습에 대한 더 정확한 정보를 쉽게 검색할 수 있게 한다. Client가 찾으려는 토픽을 중심으로 연관된 토픽과 카테고리를 나열하여 수작업으로 인한 검색시간과 잘못된 키워드 검색을 해결하였다.

In vitro experimental technique for hair research

권오상 ( Ohsang Kwon ) 대한피부과학회 2017 대한피부과학회 학술발표대회집 Vol.69 No.1

Mammalian hair follicle is a composite mini-organ with a complex structure and function. It involves several types of cells from different embryonic origins; keratinocytes, melanocytes and specialized fibroblasts such as dermal papilla cells and connective tissue sheath cells. The cells shape the highly organized, multilayered hair follicle which produces the hair, the functional endpoint of it. A range of in vitro models have been developed to investigate the biological and biochemical mechanisms of hair follicles and to explore and evaluate candidates with hair-growth modulating activity. 1. Primacy cultures: Various cell types have been established including dermal papilla cells, outer root sheath cells, connective tissue sheath cells and melanocytes. These have allowed the assessment of characteristics of individual cell types with or without manipulation in vitro and also enable to investigate their interactions. 2. Hair follicle organ culture model: One of the most popular in vitro techniques which involve more natural cellular interactions between cell types and can produce new hair, while still retaining the ability to be manipulated in vitro. In this course, basic knowledge and techniques will be discussed how to prepare and set up in vitro culture system including primacy cell culture of different cell types and hair follicle organ culture.