• 한국가축번식학회지
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• 제16권4호
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• pp.387-397
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• 1993

To examine local response of adenosie(purine nucleoside) on the developing mammary gland, Elvax 40P implants containing adenosine were surgically implanted into mammary fat pad of the five week old female ICR mice. Inguinal(the 4th) mammary glands of anesthetized mice were exposed andplaced the implants for 12 days. One gland was treated with an adenosine implant, while the contralateral gland received a blank implant as control. For whole-mount preparations, glands were stained with alum carmine, and for histological observation, micro-selected mammary glands were stained with hematoxylin and eosin Y. Implantation with Elvax 40P did not affect on the damage of neighboring mammary tissue. Adenosie 25 or 250$\mu\textrm{g}$ per slow-release implant stimulated local mammary end bud formation of ovariectomized mice such as end bud size and numbers of end bud per gland in a dose dependent manner(P<0.05), and lower concentration of adenosie(2.5 or 25$\mu\textrm{g}$/implant) increased numbers of end bud(P<0.05) and end bud size(P<0.1) of intact mice. Adenosine treatment and intact ovarian function had moderate interation effects on the stimulation of end bud formation at 2.5$\mu\textrm{g}$ adenosine/implant(P<0.1). In histological observation, adenosine implants increased numbers of mammary epithelial type of cells at mammary duct in the presence or absece ofovary. These results indicate that adenosine should be one of regulators in mouse mammary ductal growth.

• 한국안전학회지
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• 제33권2호
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• pp.152-157
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• 2018

The degradation and damage of the components for ballasted track could be caused a serious problem for railway safety. Therefore, the integrity evaluation of ballasted track condition is important to ensure and predict that the track safety and track maintenance. Various track components such as rail pad, ballast, sleeper, and rail that are widely used in Republic of Korea and represent a range of physical properties have been selected for this research. In this study, the experimental modal analysis was performed by the non-destructive testing. Modal test results were obtained from the field test and used to assess the condition of the track components. From the field test, the system of ballasted track was found to be simplified as a two-degree-of-freedom(2DOF) dynamic system. The condition of track component was found to directly affect the dynamic response of ballasted tracks. As the results, the dynamic properties of the track component was depend on the track condition and was distributed more roughly and over a wider range than its initial design values. Further, the methodology presented in this study is possible to determine experimentally the fundamental track parameters which are required in the numerical analysis, and also are useful for the safety assessment of track condition.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 춘계학술대회 논문집
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• pp.408-414
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• 2014

After drilling operations at the offshore plant to production to crude oil to high pressure. After that time the low pressured of pipe inside when the secondary produce so oil recovery is reduced. At that time injection sea water at the pipe inside through water injection pump that the device Increase recovery so to be research and development at many industry. So developing 3-stage water injection pump at the domestic company. A variety of mathematical analysis during the detailed design analysis was not made through the dynamics characteristic. In this paper, a 2D finite element analysis is performed through the dynamics of the present study was the validation of the model.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제52권9호
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• pp.418-423
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• 2003

This paper describes an electronic compass using micromachined X- and Y-axis micro fluxgate sensors which were perpendicularly aligned each other to measure X- and Y-axis magnetic fields respectively. The fluxgate sensor was composed of rectangular-ring shaped magnetic core and solenoid excitation(49 turns) and pick-up(46 turns) coils. Excitation and pick-up coil patterns which were formed opposite to each other wound the magnetic core alternatively to improve the sensitivity and to excite the magnetic core in an optimal condition with reduced excitation current. The magnetic core has DC effective permeability of ~1000 and coercive field of ~0.1 Oe. The magnetic core is easily saturated due to the low coercive field and closed magnetic path for the excitation field. To decrease the difference of induced second harmonic voltages from X- and Y-axis, excitation condition of 2.8 $V_{P-P}$ and 1.2 MHz square wave was selected. Excellent linear response over the range of -100 $\mu$T to +100 $\mu$T was obtained with 210 V/T sensitivity. The size of each micro fluxgate sensor excluding pad region was about 2.6${\times}$1.7 $mm^2$ and the power consumption was estimated to be 14 mW.W.

• 제어로봇시스템학회논문지
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• 제4권4호
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• pp.525-533
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• 1998

A conventional contact type brake system which uses a hydraulic system has mny Problems such as time delay response due to pressure build-up, brake pad wear due to contact movement, bulky size, and low braking performance in high speed region. As vehicle speed increases, a more powerful brake system is required to ensure vehicle safety and reliability. In this work, a contactless brake system of an eddy current type is proposed to overcome problems. Optimal torque control which minimizes a braking distance is investigated with a scaled-down model of an eddy current type brake. It is possible to realize optimal torque control when a maximum friction coefficient (or desired slip ratio) corresponding to road condition is maintained. Braking force analysis for a scaled-down model is done theoretically and experimentally compensated. To accomplish optimal torque control of an eddy current type brake system, a sliding mode control technique which is, one of the robust nonlinear control technique is developed. Robustness of the sliding mode controller is verified by investigating the braking performance when friction coefficient is varied. Simulation and experimental results will be presented to show that it has superior performance compared to the conventional method.

• 한국정보시스템학회지:정보시스템연구
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• 제32권2호
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• pp.63-85
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• 2023

Purpose According to a recent survey, more than 90% of customers make purchase or use decisions for their products and services, primarily based on word-of-mouth(WOM) information (reviews, recommendations, ratings, etc.). However, few studies have explored what factors influence user's WOM intention in the context of OTT service. To address this gap, this study investigates the antecedent factors of WOM intention by adopting stimulus-organism-response (SOR) theory and pleasure arousal dominance (PAD) theory as a theoretical basis. Design/methodology/approach The research model consists of stimulus factors (diversity of original content, aesthetics, interactivity, personalization quality), emotional factors (pleasure, excitement, dominance), and behavioral factor (WOM intention). The research hypothesis was tested using the survey data collected from OTT service users of 305. Findings The result reveals that diversity of original content significantly affects on pleasure and arousal whereas it is not associated with dominance. Findings indicate that aesthetics positively influences pleasure, and interactivity is not associated with arousal. It is also proven that personalization quality has a positive effect on dominance. In addition, pleasure, arousal, and domination are proven to be positively and significantly related to WOM intention.

• 한국산학기술학회논문지
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• 제18권4호
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• pp.175-182
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• 2017

본 와이어 본딩은 발광 다이오드의 패키징 공정에서 매우 중요한 공정으로 금 와이어를 이용하여 발광 다이오드 칩과 리드 프레임을 연결함으로써 다음 공정에서의 전기적 작동을 가능하게 한다. 와이어 본딩 공정은 얇은 금속선을 연결하는 공정으로 열 압착 본딩(thermo compression bonding)과 초음파 본딩(ultra sonic bonding)이 있다. 일반적인 와이어 본딩 공정은 LED 칩 상부 전극 부위에 볼 모양의 본딩을 진행하는 1st ball bonding 공정, loop를 형성하여 다른 전원 연결부위로 wire를 늘어뜨리는 looping 공정, 다른 전극 부위 상부에 stitch를 형성하여 bonding 하는 2nd stitch bonding으로 구분된다. 본 논문에서는 발광 다이오드 다이 본딩 공정에 영향을 주는 다양한 공정 변수에 대하여 분석을 수행하였다. 그리고 반응 표면 분석법을 통하여 Zener 다이오드 칩과 PLCC 발광 다이오드 패키지 프레임을 연결하는 공정 최적화 결과를 도출하였다. 실험 계획법은 5인자, 3수준에 대하여 설정하였으며 4가지 반응에 대하여 인자를 분석하였다. 결과적으로 본 연구에서는 모든 목표에 맞는 최적 조건을 도출하였다.

• 만화애니메이션 연구
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• 통권30호
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• pp.221-243
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• 2013

전통적인 인쇄매체의 종이책이 최근 디지털 기술의 발달로 인해 스마트기기에서도 전자책이라는 매체로도 확장 되고 있다. 특히 애플리케이션(Application) 형태의 콘텐츠로 제공되는 앱북(App Book)은 책이 가지고 있는 기본적인 정보제공과 교육, 감성전달 목적 이외에 멀티미디어 기술을 활용한 재미 요소를 부가하여 몰입도를 배가 시키고 체험적 효과를 증가시키고 있다. 기존에 이미 검증받은 고퀄리티 콘텐츠를 애플리케이션 매체로 전환하는데 있어서 그 효과를 높이기 위해 다양한 시도들이 이루어지고 있다. 본 논문은 앱북으로의 매체 전환에 있어서 디지털 기술과 재미 요소가 융합된 퍼놀로지(Funology)가 어떻게 활용되고 사용자에게 어떠한 효과를 제공하는지에 대해 사례를 분석하여 앞으로의 앱북 콘텐츠 개발에 가이드를 제공하고 활용될 수 있도록 하고자 한다. 본 논문에서는 첫째, 문헌조사를 통해 퍼놀로지에 대한 개념과 요소들을 살펴보고 분석할 수 있는 기준의 토대를 마련한다. 둘째, 원작 '무, 바, 라라라!(Moo, Baa, La La La!)' 그림책을 아이패드(iPad)용 애플리케이션으로 전환한 앱북을 선정하여 퍼놀로지 요소에 따라 분석하였다. 셋째, 분석한 요소들이 실제로 인쇄매체의 종이책과 비교하여 퍼놀로지의 활용과 효과를 확인하기 위해 심층인터뷰인 FGI(Focus Group Interview)를 실행하였다. 그 결과 사운드를 활용한 감각적 퍼놀로지에 대한 감성적 효과가 높았으며 즉각적이고 직관적인 모션과 변화에 따른 인터랙션에 의한 퍼놀로지 요소를 선호하고 있었다. 또한 기존의 오리지널 책에서 강조되던 유희 자체를 위한 퍼놀로지 요소는 다른 관점에서의 즐거운 감성으로 유도하고 있어 책의 콘텐츠 내용과 정보 보다는 게임적 성향의 인터랙션 자체에 더욱 치중되어 체험하고 있음을 알 수 있었다. 이러한 분석과 인터뷰 결과는 지속적으로 개발되고 있는 앱북 개발에 있어서 본래 책이라는 매체가 가지고 있는 콘텐츠의 장점을 살리면서 애플리케이션의 퍼놀로지 요소의 특징을 부각시킬 수 있는 매체전환 방법에 대한 활용 가능성을 기대해 본다.

• Journal of Microbiology and Biotechnology
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• 제29권5호
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• pp.739-748
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• 2019

Cheonggukjang and chaga mushrooms have numerous health benefits, and have been used in alternative medicine. Therefore, a powder mixture of 98: Cheonggukjang and 2: Chaga extracts was fermented with Lactobacillus acidophilus KCTC3925 (FCC) and its anti-obesity effects in high-fat diet (HFD)-induced obese mice were determined. Five-week-old male ICR mice were fed a normal diet or HFD in the presence or absence of 3% and 5% FCC by weight (n = 10 per group). After 12 weeks, the mice were sacrificed, and the serum and tissue samples were collected for analysis. Body weight and epididymal fat pad weight were significantly lowered in the 3% and 5% FCC groups compared with those in the HFD control group (p < 0.01). FCC supplementation suppressed serum triglyceride and increased serum HDL-C levels (p < 0.01). Serum GOT, GPT, and leptin levels, hepatic COX-2 mRNA expression, and splenic COX-2 and IL-4 mRNA expression were significantly higher in the HFD groups than in the control group (p > 0.05); however, except for splenic IL-4 levels, the increases were significantly attenuated by FCC supplementation. Expression of ICAM-1, an aortic inflammatory marker, was significantly increased in the HFD group; this effect was suppressed in the 3% FCC group (p < 0.01) but not in the 5% FCC group. FCC suppressed the body weight and epididymal fat pad weight gain, as well as inflammatory responses in the liver and spleen of HFD-fed mice. Thus, FCC supplementation will be beneficial for the treatment of obesity-related effects.

• 한국구조물진단유지관리공학회 논문집
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• 제25권6호
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• pp.154-160
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• 2021

최근에는 도심속에서 공사가 진행되는 경우가 크게 늘고 있는데, 이로 인해 기존 구조물 인근에서 공사에 의한 인위적인 진동이 자주 발생하기도 하고, 산업단지의 경우는 주변 기계류 작동 등에 의해서도 진동이 야기되어 문제가 발생하기도 한다. 한편, 구조물을 구성하고 있는 일반 콘크리트의 경우, 진동에 대한 감쇠성능이 작아, 구조물에 발생하는 진동뿐만 아니라 지반진동과 같이 외부로부터 구조물로 전달되는 다양한 진동을 차단하는데 어려움이 따른다. 이러한 지반을 통해 구조물로 전달되는 진동을 차단하기 위해서, 최근 폴리머 콘크리트를 활용하여 댐핑 성능을 크게 증가시킨 고 감쇠 시스템에 대한 연구가 활발히 진행되고 있다. 또한, 폴리머 콘크리트는 압축, 휨, 인장강도 등의 물리적 특성과 동적 특성이 매우 우수한 것으로 알려져 있어, 지반과 접한 구조물과 같이 큰 압력에 저항하면서 진동저감이 요구되는 구조물에의 폭넓은 활용이 기대되는 구조재료라 할 수 있다. 따라서, 본 연구에서는 폴리머 콘크리트의 지반진동 저감성능을 검토하기 위하여, 일반 콘크리트, 폴리우레탄 패드, 발포고무 패드와의 성능을 비교하였으며, 동적 특성으로 주파수 응답함수와 진동가속도에 대한 검토를 진행하여, 폴리머 콘크리트와 각각의 재료가 지하구조물에 적용될 경우의 동적 특성을 비교 검증한 후, 실 구조물에의 적용 가능성에 대해 검토하고자 한다.