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Hyun Woo Kim 대한전자공학회 1996 대한전자공학회 세미나 Vol.1996 No.-

A Pilot Project of Systematic Tuberculosis Screening in the Elderly in a South Korean Province

( Hyunwoo Kim ),( Hee-jin Kim ),( Kyung-hyun Oh ),( Hwan-wook Oh ),( Hongjo Choi ) 대한결핵 및 호흡기학회 2019 Tuberculosis and Respiratory Diseases Vol.82 No.3

Background: Tuberculosis (TB) is a major infectious disease in South Korea causing substantial disease burden, particularly in the elderly. This study aimed to identify the case detection rate of mobile TB screening for the elderly conducted in the Jeollanam-do region and to analyze risk factors of active TB. Methods: We screened the elderly population (≥65 years old) in Jeollanam-do from August to December 2017. Chest radiography was performed for all participants. Participants with TB presumptive signs were asked to submit sputum specimen(s). Sputum smear, culture, and polymerase chain reaction analyses were performed. Cascade analysis, chisquared tests, and Fisher exact tests were used to evaluate screening performance. Results: In total, 12,402 participants were screened, and 211 (1.7%) were suspected to have active TB; 181 of the suspected patients (85.8%) underwent sputum smear test, and 16 (8.8%) patients were confirmed to have TB. The TB prevalence among the elderly was bacteriologically confirmed to be 129 per 100,000 individuals, which was similar to national TB notification data for the same age groups. The proportion of active TB cases increased with age, and differed based on sex and past TB history. However, TB-related symptoms, comorbidity status, and TB screening history within 12 months were not predictive of active TB. Conclusion: This study identified that the prevalence rate was similar to national TB notification data from the same age groups. Periodic, community-based, systematic TB screening among the elderly population is recommended.

Apoptotic Effects of 6-Gingerol in LNCaP Human Prostate Cancer Cells

Hyun-Woo Kim,Deuk-Hee Oh,Chaeyong Jung,Dong-Deuk Kwon,Young-Chai Lim 순천향대학교 순천향의학연구소 2011 Journal of Soonchunhyang Medical Science Vol.17 No.2

Objective: 6-Gingerol, one component of ginger (Zingiber officinale) compound, has been known to possess anti-inflammatory, analgesic, anti-emetic, and anti-cancer effects. In this study, the apoptotic ability of 6-gingerol was investigated in human prostate cancer cells. Methods: 3-(4,5-Dimethylthiazol-2-yl)- 2,5-diphenyl-tetrazolium bromide (MTT) assay, flow cytometry, and western blot analysis were done in LNCaP human prostate cancer cell lines treated with the various doses of 6-gingerol for the different durations of drug exposure. Results: 6-Gingerol in doses ranging from 100 to 300 μM induced dose- and time-dependent inhibition of cell viability in prostate cancer cells by using MTT assay. Maximal inhibition of cell viability was observed at 300 μM of 6-gingerol for 48 hours treatment in LNCaP cells. 6-Gingerol at the dose of 100 μM did not produce any significant change in apoptotic cells in flow cytometry analysis. However, significant increase in sub-G0/G1 phase was observed in cells treated with 200 and 300 μM of 6-gingerol. Any significant cell cycle arrest was not induced by 6-gingerol. In western blotting analysis, expression of caspase-3 was not evident in cells treated with 6-gingerol for 24 hours. However, 48 hours treatment with 6-gingerol altered the expression of caspase-3 in LNCaP cells. Expression of cleaved poly showed the dose-dependent fashion in both 24 hours and 48 hours treatment of 6-gingerol. Conclusion: These observations suggest that 6-gingerol may induce apoptosis in LNCaP human prostate cancer cells.

Effect of Social Isolation and Sports Broadcast Viewing Type on Level of Depression

( Hyun-woo Kim ) 한국체육학회 2021 International journal of human movement science Vol.15 No.2

This study demonstrates that the effects of social isolation on depression levels may be partially mitigated by sports broadcast viewing activities. In the experiment, two versions of sample sports broadcasting videos were created and shown to test subjects to identify differing effects of traditional viewing and social viewing. The basic data collection involved a survey of 48 male and female participants in their twenties and thirties, the age group known to engage in social viewing most actively. The repeated ANOVA for 2(Perceived Isolation: High vs. Low) × 2(Social Disconnectedness: High vs. Low) × 2(Viewing Type: Traditional Viewing vs. Social Viewing) was conducted in order to test the hypotheses. The subjects’ levels of depression were measured three times using the Visual Analogue Scale (VAS); before watching the sample video, after watching the video, and five minutes after the end of viewing. The results of the experiment support the main effect of perceived isolation on the level of depression as well as the interaction effect between social disconnectedness and viewing type.

Schottky Barrier Tunnel Field-Effect Transistor using Spacer Technique

Hyun Woo Kim,Jong Pil Kim,Sang Wan Kim,Min-Chul Sun,Garam Kim,Jang Hyun Kim,Euyhwan Park,Hyungjin Kim,Byung-Gook Park 대한전자공학회 2014 Journal of semiconductor technology and science Vol.14 No.5

In order to overcome small current drivability of a tunneling field-effect transistor (TFET), a TFET using Schottky barrier (SBTFET) is proposed. The proposed device has a metal source region unlike the conventional TFET. In addition, dopant segregation technology between the source and channel region is applied to reduce tunneling resistance. For TFET fabrication, spacer technique is adopted to enable self-aligned process because the SBTFET consists of source and drain with different types. Also the control device which has a doped source region is made to compare the electrical characteristics with those of the SBTFET. From the measured results, the SBTFET shows better on/off switching property than the control device. The observed drive current is larger than those of the previously reported TFET. Also, short-channel effects (SCEs) are investigated through the comparison of electrical characteristics between the long- and shortchannel SBTFET .

Simulation Study for Logistics Network Redesign Problem: A Case Study of Beverage Company in Korea

Hyun-Woo, Kim,Kwang-Tae, Kim 대한산업공학회 2022 대한산업공학회 춘계학술대회논문집 Vol.2022 No.6

Individual and Contextual Determinants of Ethnic Exclusionism Attitudes toward Immigrants in South Korea

Hyun Woo Kim,Aggie J. Noah 한국사회학회 2016 韓國社會學 Vol.50 No.6

The rapid increase of immigration in South Korea and divided public opinions towards immigration among Korean natives make it imperative to investigate the sources of natives’ ethnic exclusionism attitudes toward immigrants. Using data from the 2010 Korean General Social Survey (KGSS) and the 2010 Population and Housing Census in a multilevel modeling framework, we investigate the individual and contextual factors associated with ethnic exclusionism attitudes among Korean natives. Consistent with previous studies, we find that a number of individual factors, including education level and political ideology, are associated with ethnic exclusionism attitudes. Supporting the contact theory of racial and ethnic relations, we find that the percentage of multicultural households in respondents’ neighborhood—measured as the ward of residence—is positively associated with more favorable attitudes toward multicultural society. These findings suggest that researchers should consider both individual and contextual factors to gain a comprehensive understanding of ethnic exclusionism attitudes in Korea.

Design and Control of a Sphere Robot Using a Control Moment Gyroscope Actuator for Navigation

Hyun Woo Kim,정슬 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.12

In this paper, the design and control of a sphere robot are presented. A small double gimbal control moment gyroscope(DGCMG) designed and analyzed as an indirect actuator for the rotational torque generation. The heading angle of the robot is controlled by a DGCMG and the driving position is controlled by DC motors. The DGCMG has been developed in a scissored-pair configuration which has two gimbals in the opposite direction to maximize the induced torque by double and cancel out the unwanted torque in the plane. Experimental studies of not only position control but also heading control of the sphere robot commanded by a joystick are conducted to demonstrate the functionality of the robot.

Study on the Influence of Drain Voltage on Work Function Variation Characteristics in Tunnel Field-effect Transistor

Hyun Woo Kim,Jang Hyun Kim 대한전자공학회 2020 Journal of semiconductor technology and science Vol.20 No.6

This paper investigates the influence of drain voltage (VDS) on the work function (WF) variation (WFV) characteristics in the tunnel field-effect transistor (TFET). For sub-45 nm node technology, the high-κ and metal gate (HKMG) have been proposed to improve the TFET’s weakness for the low Ion. However, the metal gate brings WFV in the gate due to various metal particle directions. Based on the technology computer-aided design (TCAD) simulations, the transfer characteristics, channel potential, and charge density are analyzed to confirm the relation between WFV and VDS. From the simulation results, the phenomena that WFV effects get decreased with lower VDS can be described as a channel potential pinning. This pinning is occurred by inversion charges supplied from the drain to the channel. Therefore, when low VDS is applied, the channel potential does not be modulated proportionally to the applied gate voltage (VGS). Then, it induces the limitation of tunneling occurred from the source to the channel resulting in the decrease of WFV in the TFET.

Non-surgical periodontal treatment using the erbium, chromium: yttrium-scandium-gallium-garnet (Er, Cr:YSGG) laser in chronic periodontitis: Case reports

( Hyun-woo Kim ),( Won-pyo Lee ),( Sang-joun Yu ),( Byung-ock Kim ) 조선대학교 구강생물학연구소 2017 Oral Biology Research (Oral Biol Res) Vol.41 No.3

The medical (or dental) necessity of the application of adjuvant laser therapy after periodontal treatment is debatable, but has many demonstrable advantages. The advantages of laser irradiation are hemostatic effect, calculus ablation, bactericidal effect and detoxification. The purpose of this study was to identify and measure the clinical results obtained with the implementation of adjuvant laser therapy (in addition to and) following scaling and root planing procedures. Three patients (with an overall periodontal probing depth of less than 6 mm) were selected. Patients with systematic disease were excluded. Probing depth, bleeding on probing and full mouth standard radiography were tested at baseline, and then again at three months after treatment. At the time of the first visit, supra-gingival calculus was removed using ultrasonic scaler (Cavitron™ Plus™, Dentsply, Swiss). At the time of the second visit, the laser was irradiated with a radial firing tip (RFPT 5-14) of Er, Cr:YSGG laser (2.78 μm, 1.5 W, repetition rate of 30 Hz, 11% air, 20% water). The laser irradiation on the root surface was approached at 15 to 30 degrees, and without direct contact with the root surface. The total time of irradiation was 30 seconds for buccal (about fifteen seconds) and lingual sides (about fifteen seconds). Calculus ablation was selfevident and could be easily observed on plain radiograph at three months post-treatment. Reduced bleeding was appreciated when probing depth was measured. As well, the clinical attachment level was noted to be improved at three months post-treatment. The results of this study strongly indicate that laser therapy can be effective in improvement of chronic periodontitis and reduction of periodontal pocket depth.