• 한국수소및신에너지학회논문집
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• 제1권1호
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• pp.48-54
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• 1989

Semiconductive property of the passivating $TiO_2$ film was investigated by measuring the impedance of passivated titanium electrode in a 0.1 N NaOH solution. The passive film was prepared galvanostatically with $10mA/cm^2$ at formation potential of 50 V in a 1 N $H_2SO_4$ solution. The impedance measurement was conducted by superimposing an ac voltage of 5 m V amplitude with the frequency ranging from 5 to 10000 Hz on a dc bias (applied potential). The donor distribution in the film was depicted from the analysis of the non-linear slope of Mott-Schottky plot. The region with nearly constant concentration of donors near the electrolyte/film interface amounts at about 60 percent of the total film thickness and donor concentration increases largely with distance from the surface in an inner region near the film/metal interface. In a region of the film/metal interface the donor concentration showed a frequency dependence greater than in a region of the electrolyte/film interface. The result of donor concentration against frequency suggests a transition from crystalline to amorphous state with distance from the electrolyte/film interface in the passivating $TiO_2$ films. This is also confirmed by the ac conductivity measurement.

• International Journal of Control, Automation, and Systems
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• 제3권1호
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• pp.130-136
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• 2005

A new optical digitizing system for determining the position of a cursor in three dimensions(3D) and an experimental device for its measurement are presented. A semi-passive system using light intensity modulation, a technology that is well known in radar ranging, is employed in order to overcome precision limitations imposed by background light. This system consists of a charge-coupled device camera placed before a rotating mirror and a light-emitting diode whose intensity is modulated. Using a Fresnel pattern for light modulation, it is verified that a substantial improvement of the signal to noise ratio is realized for the background noise and that a resolution of less than a single pixel can be achieved. This opens the doorway to the realization of high precision 3D digitized measurement. We further propose that a 3D position measurement with a monocular optical system can be realized by a numerical experiment if a linear-period modulated waveform is adopted as the light-modulating one.

• Archives of Pharmacal Research
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• 제24권3호
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• pp.249-255
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• 2001

We studied the effect of aqueous extract of Magnolia officinalis bark (Magnoliaceae) (MOAE) on the immediate hypersensitivity reaction. MOAE (0.01 to 1g/kg) dose-dependently inhibited compound 48/80 induced systemic anaphylaxis in rats. MOAE (0.1 and 1g/kg) also significantly inhibited local immunoglobulin E (lgE)-mediated passive cutaneous anaphylactic reaction. When MOAE was pretreated at concentrations ranging from 0.01 to 1g/kg, the levels of plasma histamine were reduced in a dose-dependent manner. MOAE (0.001 to 1 mg/ml) dose-dependently inhibited the histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80 or anti-dinitrophenyl (DNP) Igl. The level of cyclic AMP (CAMP) in RPMC, when MOAE was added, significantly increased compared with that of the normal control. Moreover, MOAE (0.01 to 1 mg/ml) had a significant inhibitory effect on anti-DNP Igl-induced tumor necrosis factor-$\alpha$ production from RPMC. These results indicate that MOAE inhibits immediate hypersensitivity reaction in vivo and in vitro.

• 대한가정학회지
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• 제36권7호
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• pp.83-96
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• 1998

The purpose of this study was the development of a scale to assess daily hassles coping behaviors for school aged children. The subjects were 398 children consisted of 197 3rd grade an 201 6th grade. They were selected from elementary school in Seoul, InCheon, DaeJeon, GwangJu and Pusan(202 males and 196 females) A questionnaire as the methodological instrument composed of 65-item daily hassles coping scale, demographic questions, 27-item Children's Depression Inventory and 20-item Locus of Control Scale. Statistics such as mean, %, X2, Cramer's V, Cronbach's α, factor analysis and Person's γ was used for used data analysis. The major findings of this study were as follows; 1)55 items of the 65-item scale were selected through item discriminant method. The discriminant coeffcients of the items(Cramer's V) ranged from .35 to .68. 2)5 factors were extracted from the 1st and the 2nd factor analysis. The subscales labelled 'active' 'passive' 'aggressive' 'avoidant' and 'social support seeking' coping. The criterion validity of this scale was assessed by computing the correlation measures of Children's Depression Inventory and Locus of Control Scale with this scale. Most coefficients were significant(ranging from r=-.16 to r=.40,p<.01,p<.001), although their correlations were modest. 3)Finally, the internal consistency of this scale appeared to be at an acceptable level(Cronbach's α=.90)

• 동의생리병리학회지
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• 제26권1호
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• pp.40-46
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• 2012

Cigarette smoking is known to be associated with various chronic pulmonary and cardiovascular diseases ranging from inflammation to cancer. Not only first-hand smoke but also second-hand smoke is suggested to be a factor of health risk. This study was to investigate whether Platycodi Radix extract administration would alter oxidative stress in lung leading to protection of cigarette smoke-induced lung damage. Sprague-Dawley rats were randomly divided into 3 groups; Intact, Smoke+PR and Smoke+Vehicle. In Smoke+PR and Smoke+Vehicle group, the exposure to cigarette smoke was performed for 15 min/day for 4 weeks in ventilated smoking chamber. The Platycodi Radix extract and saline were orally administrated to Smoke+PR and Smoke+Vehicle group each. The rats of Intact group were just kept in ventilated chamber without cigarette smoke. After the experiment for 4 weeks, the lung tissues were collected for histological observation and immunohistochemistry. In Results, airspace enlargement and goblet cell hyperplasia were observed after 4 weeks' exposure to cigarette smoke. Whereas, the oral administration of Platycodi Radix extract for 4 weeks reduced airspace enlargement and goblet cell hyperplasia. Moreover, the alterations of BAX/Bcl-2 proteins in lung tissues were observed. These results suggest that Platycodi Radix extract ameliorates lung damage in cigarette smoke-exposed rats and has protective effects on second-hand smoke injury.

• Advances in aircraft and spacecraft science
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• 제9권2호
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• pp.131-148
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• 2022

The paper presents the surface-modified NACA 2412 airfoil performance with variable cavity characteristics such as size, shape and orientation, by numerically investigated with the pre-validation study. The study attempts to improve the airfoil aerodynamic performance at 30 m/s with a variable angle of attack (AOA) ranging from 0° to 20° under Reynolds number (R_e) 4.4×10⁵. Through passive surface control techniques, a boundary layer control strategy has been enhanced to improve flow performance. An intense background survey has been carried out over the modifier orientation, shape, and numbers to differentiate the sub-critical and post-critical flow regimes. The wall-bounded flows along with its governing equations are investigated using Reynolds Average Navier Strokes (RANS) solver coupled with one-equational transport Spalart Allmaras model. It was observed that the aerodynamic efficiency of cavity airfoil had been improved by enhancing maximum lift to drag ratio ((l/d) max) with delayed flow separation by keeping the flow attached beyond 0.25C even at a higher angle of attack. Detailed investigation on the cavity distribution pattern reveals that cavity depth and width are essential in degrading the early flow separation characteristics. In this study, overall general performance comparison, all the cavity airfoil models have delayed stalling compared to the original airfoil.

• 지구물리와물리탐사
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• 제22권4호
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• pp.210-224
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• 2019

표면파 탐사는 매우 작은 규모의 초음파 분석부터 지질공학 규모의 분석까지 다양한 분야에서 활용하고 있으며, 특히 천부 지질의 지반 안정성을 평가하는 데 활발히 이용되고 있다. 표면파 탐사는 기본적으로 지표면을 따라 전파하는 표면파의 분산 특성에 기초하여 매질의 전단 속도 분포를 파악하는 탐사법이다. 즉, 지하 구조가 1차원 구조라는 가정 하에 탐사를 수행하는 표면파 탐사는, 진동수와 전파 속도의 관계인 분산곡선을 분석하고 1차원적 역산을 통해 층서구조 속도를 계산하게 된다. 이 논문에서는 천부 지질 조사를 위한 표면파 탐사법의 기초적인 이론부터 전반적인 자료처리 과정을 기술보고를 통해 설명하고자 한다. 먼저, 표면파에 대한 개략적인 설명과 가장 큰 특징 중 하나인 분산 특성에 대하여 설명한 후 일반적인 표면파 자료처리 순서에 대하여 설명하였다. 표면파 탐사법은 인공적인 송신원의 유무에 따라 능동 표면파 탐사법과 수동 표면파 탐사법으로 나눌 수 있으나 이 논문에서는 능동 표면파 탐사법인 CSW, SASW, MASW에 대하여 집중적으로 기술하였다. 수동 표면파 탐사법에 대해서는 다음 기술보고에서 다루고자 한다.

• 동의생리병리학회지
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• 제16권2호
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• pp.239-244
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• 2002

Okbyungpoongsan-Gami (OG) has been used for the treatment of excessive sweating with general weakness and allergic rhinitis recently. Anal therapy is another way of taking Oriental medicine. It is an important pathway but not available in common clinical situation. This experiment was performed in order to study the inhibitory effect of immediate-type allergic reaction of OG by anal therapy. In addition, the experiment was practised by 1 H-NMR spectroscopy to examine molecular structure of OG. The results were obtained as follows : OG concentration-dependently inhibited compound 48/80- induced immediate type systemic allergic reaction with concentrations of 0.01-1.0g/kg by anal administration 1 h before injection of compound 48/80. OG also concentration-dependently inhibited compound 48/80- induced ear swelling response with concentrations of 0.01-1g/kg by anal administration 1h before injection of compound 48/80. OG also inhibited the passive cutaneous anaphylaxis activated by anti-dinitrophenyl (DNP) IgE antibody concentration- dependently at concentrations ranging from 0.01 to 1g/kg. When OG was pretreated at concentrations ranging from 0.01 to 1g/ℓ, the histamine release from the rat peritoneal mast cells induced by compound 48/80 was reduced in a concentration-dependent manner. OG (0.1-1g/ℓ) had a significant inhibitory effect on histamine release from IgE-induced activated mast cells. OG is seen to be a biochemical compound certainly by 1 H-NMR spectroscopy According to above results, anal therapy of OG may be beneficial in the treatment of systemic and local immediate-type allergic reactions by inhibition of histamine release from mast cells.

• 복식문화연구
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• 제20권6호
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• pp.883-894
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• 2012

Fashion companies are faced with more severe competition with the emergence of new types of retail formats. Retailers are coming up with new shopping values to maximize their profits and benefits of customers. The aim of this study was to study shopping values and analyze differences in store selection criteria and store visits among. The respondents were males and females with ages ranging from the 20's to the 40's, residing in Seoul and the Gyeonggi area. Data were collected via both online and offline. Data from 427 respondents were analyzed using SPSS 17.0. Results indicated that there were three categories including hedonic, informative, and reliable shopping values from the factors for clothing shopping values. They form three types of consumer groups such as active, passive-reliable, and hedonic-informative shopping value groups. These three groups were different in terms of demographic characteristics. For the factor influencing store preference, the range of product selection and customer service were the two significant features that showed substantial differences in the shopping value groups store's atmosphere, salespeople, convenient location, price, and brand store did not have significant differences across groups. Retailers of each fashion retail formats have to consider consumers shopping values for their retail decision makings.

• Architectural research
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• 제19권2호
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• pp.45-52
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• 2017

Recently, as a new perspective to view the architecture in relation to global environmental problems, interest in environmental architecture that conforms to the surrounding environment and nature with nature has been expanded as a part of the natural ecosystem, rather than seeing the building as an independent entity. Traditional Korean architecture creates a comfortable indoor environment by appropriately using the natural energy around, ranging from the arrangement of the building and the space composition to the use of detailed materials and to harmonize the artificial architectural environment without harming the natural ecosystem. The purpose of this study is to propose a method to apply the environmental control techniques of traditional buildings to modern buildings. As a research method, the characteristics of Korean traditional buildings according to the climatic characteristics of Korea were recognized through existing literature data and when applied to methods of traditional buildings, ventilation systems, control through eaves, and humidity control using Hanji the effect of energy load control on traditional buildings was analyzed and identified through existing literature. After analyzing the problems of modern architecture, we analyzed the effect of the environmental control system of traditional architecture on modern architecture. Simulation results show that the application of the environmental control system of traditional buildings to modern buildings reduces the cooling and heating load of modern buildings and has an effect on humidity control. This study suggests that quantitative energy saving will be possible if the environmental control techniques of traditional buildings are appropriately applied to modern buildings.