• Korean Journal of Animal Reproduction
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• v.16 no.4
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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.

• Journal of the Korean Society of Safety
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• v.33 no.2
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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.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.04a
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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.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.9
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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.

• Journal of Institute of Control, Robotics and Systems
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• v.4 no.4
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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.

• The Journal of Information Systems
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• v.32 no.2
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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.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.175-182
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• 2017

In light emitting diode (LED) chip packaging, wire bonding is an important process that connects the LED chip on the lead frame pad with the Au wire and enables electrical operation for the next process. The wire bonding process is divided by two types: thermo compression bonding and ultrasonic bonding. Generally, the wire bonding process consists of three steps: 1st ball bonding that bonds the shape of the ball on the LED chip electrode, looping process that hangs the wire toward another connecting part with a loop shape, and 2nd stitch bonding that forms and bonds to another electrode. This study analyzed the factors affecting the LED die bonding processes to optimize the process capability that bonds a small Zener diode chip on the PLCC (plastic-leaded chip-carrier) LED package frame, and then applied response surface analysis. The design of experiment (DOE) was established considering the five factors, three levels, and four responses by analyzing the factors. As a result, the optimal conditions that meet all the response targets can be derived.

• Cartoon and Animation Studies
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• s.30
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• pp.221-243
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• 2013

Recently, traditional books based on printing on the paper have expanded to e-book media in smart device because of developing digital technology. Especially, app book applied application makes users' experience increase and provides immersion to them, because it allows them basically delivering information, educational effect and fun elements with multimedia technology. There are various experimental trials to make enhance effect of reformatting for application media. The purpose of this study is to analyze reformatting effect for app book with funology which is convergence of digital technology and a fun. Then this article would provide design guide and be applied to new application contents. For this research, the first of all, we would discuss concept and elements of funology by publication including thesis, articles, and books. Secondly, this article will be focused on 'Moo, Baa, La La La!' which is reformatting application for iPad to analyze type of funology. Thirdly, we would make sure that app book makes users get emotional effect comparing original book by FGI(Focus Group Interview). In conclusion, sensitive funology used the sound allows user emotional effect and they prefer to intuitive and immediate motion and response of interactive funology. In other way, funology of fun in itself which is strong concept in original book diminishes in app book. Then users concentrate interactive factors like game structure. This results make that app books could be created by strength of original contents and advantage of funology. Therefore this makes us expect the possibility of reformatting effect with funology and we need to discuss the points of issue that there are considerations and limitations to successful app book for users.

• Journal of Microbiology and Biotechnology
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• v.29 no.5
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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.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.6
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• pp.154-160
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• 2021

Recently, there have been increasing construction works carried out in urban centers, which are inducing frequent artificial vibration in the vicinity of existing structures due to such construction works. moreover, in case of industrial estates, vibration is induced due to operation of machines in the surrounding areas, thereby causing problems. meanwhile, in case of ordinary concrete that compose structure has low level of damping capability for vibration. accordingly, there are difficulties in blocking a wide range of vibrations delivered to the structures from outside including not only vibrations generated in the structures themselves but also ground vibration. recently, numerous studies are being carried out actively on high-damping system that markedly enhanced the damping performances of structures by utilizing polymer concrete in order to block the vibrations delivered to the structures through ground. therefore, this study compared the performances of polymer concrete with those of ordinary concrete, polyurethane pad and foamed rubber pad in order to review its performances in reducing ground vibration. for this purpose, review of FRF and vibration acceleration as dynamic characteristics was made. after comparative verification on the dynamic characteristics is made when polymer concrete and other aforementioned materials are applied to underground structures, the possibility of application of polymer concrete to structures is reviewed.