• 제목/요약/키워드: Seung-Kook

Search Result 905, Processing Time 0.029 seconds

Fabrication of 3-D structures using hybrid imprint lithography (Hybrid Imprint Lithography 공정을 이용한 3D 구조물 제작)

  • Sin, Sang-Hyun;Kim, Han-Hyoung;Yang, Seung-Kook;Lee, Jong-Geun;O, Beom-Hoan;Lee, Seung-Gol;Lee, Il-Hang;Park, Se-Geun
    • Proceedings of the IEEK Conference
    • /
    • 2008.06a
    • /
    • pp.509-510
    • /
    • 2008
  • Hybrid Imprint Lithography (HIL) is proposed where photolithography and imprinting processes are employed. Fabrication step of multilevel or three dimensional patterns is suggested. The method of controlling residual layer thickness after imprinting is developed. The thickness of residual layer changes lineally with imprinting time and can be controlled. Polymer patterns fabricated by this HIL is demonstrated.

  • PDF

Fabrication of PDMS micro-pads for vibration absorber in MEMS packaging (MEMS packaging을 위한 Micro PDMS pad 제작)

  • Kim, Han-Hyoung;Sim, Se-Hwan;Kim, Sung-Gi;Yang, Seung-Kook;O, Beom-Hoan;Lee, Seung-Gol;Lee, El-Hang;Park, Se-Geun;Lee, Jong-Geun
    • Proceedings of the IEEK Conference
    • /
    • 2008.06a
    • /
    • pp.511-512
    • /
    • 2008
  • Micro-pads made of PDMS(polydimethylsiloane) can be mechanical shock or vibration absorber because of its contractibility. Fabrication of micro-pads and techniques of separation from substrate and attachment to new substrate are developed. Three micron thick PDMS pads were fabricated by imprinting lithography.

  • PDF

Strength Analysis for Compressed Coil Spring in the Gage - Adjustable Wheelset System (궤간 가변 윤축의 압축스프링에 대한 강도해석)

  • Kim, Chul-Su;Ahn, Seung-Ho;Chung, Kwang-Woo;Jang, Seung-Ho;Jang, Kook-Jin;Kim, Jung-Kyu
    • Proceedings of the KSR Conference
    • /
    • 2007.11a
    • /
    • pp.1012-1017
    • /
    • 2007
  • To reduce the cost and the time of transport in Eurasian railroad networks such as TKR(Trans-Korea Railway), TCR(Trans-China Railway) and TSR(Trans-Siberia Railway) owing to the problem of different track gauges (narrow/standard/broad gauge), it is important to develop the gauge - adjustable wheelset system to adapt easily to these gauges. Moreover, this system accomplishes periodically a conversion operation from the gauge variable segment between different gauge. Gauge adjustable compression coil spring during conversion process accomplishes repetitively a central role for operation mechanism between flange and locking part. Therefore, to assure the safety of the gauge-adjustment wheelset system, it is necessary to stress analysis of the optimized spring in the system. In this study, it was performed to optimal design of the spring for stress analysis by using the genetic algorithm.

  • PDF

A study on the Potential Detection System of Gas Insulated Switchgear (가스절연개폐장치의 전위감지 시스템에 대한 연구)

  • Choi, Seung-Kil;Baek, Seung-Kook;Kim, Kwang-Ho;Kang, Hyung-Boo
    • Proceedings of the KIEE Conference
    • /
    • 1999.07e
    • /
    • pp.2284-2286
    • /
    • 1999
  • This paper describes the development of potential detection system in 22.9kV gas insulated switchgear. This system composed with main system and LPS can detect the source voltage by capacitive potential division which is accomplished by inserting signal electrode between main electrode and earthed metal enclosure of the switchgear. The appropriate position of signal electrode is achieved by numerical analysis using finite element method. The developed potential detection system is verified by several tests such as voltage test, swc test and others and by applicaion at site. From the results, it is concluded that potential detection system is very reliable and available to operate the switchgear safely.

  • PDF

Durability Evaluation of the Gage - Adjustable Wheelset System According to UIC Standard (UIC 기준에 따른 궤간 가변 윤축의 내구성 평가)

  • Kim, Chul-Su;Ahn, Seung-Ho;Chung, Kwang-Woo;Jang, Seung-Ho;Jang, Kook-Jin;Kim, Jung-Kyu
    • Proceedings of the KSR Conference
    • /
    • 2008.06a
    • /
    • pp.2156-2162
    • /
    • 2008
  • To reduce the cost and the time of transport in Eurasian railroad networks such as TKR, TCR and TSR owing to the problem of different track gauges (narrow/standard/broad gauge), it is important to develop the gauge - adjustable wheelset system to adapt easily to these gauges. The gauge - adjustable wheelset system in the transcontinental railway have been proposed as a more effective way in comparison with other techniques for overcoming difference in track gauges. Assume that the freight train with gauge adjustable wheelset system is running from domestic train network to TCR, TSR in Eurasian continent, it is necessary to estimate the safety of this system. This study is evaluated at examination of safety for freight train with gauge adjustable wheelset system by simulated durability analysis. Moreover, the predicted fatigue life at running track using the durability simulator was verified by the durability test according to UIC standard.

  • PDF

Plasma damage of MIS(TaN/$HfO_2$/Si) capacitor using antenna structure (Antenna structure를 이용한 MIS(TaN/$HfO_2$/Si) capacitor의 plasma damage 연구)

  • Yang, Seung-Kook;Lee, Seung-Yong;Yu, Han-Suk;Kim, Han-Hyung;Song, Ho-Young;Lee, Jong-Geun;Park, Se-Geun
    • Proceedings of the IEEK Conference
    • /
    • 2006.06a
    • /
    • pp.551-552
    • /
    • 2006
  • Plasma-induced charging damage was been measured during TaN gate electrode of MISFET(TaN/$HfO_2$/Si) or interconnection metal etching step using large antenna structures. The results of these experiments were obtained that $HfO_2$ gate dielectric layer was affected about plasma charging effects and damage increased with F-N tunneling. Therefore, the etching conditions should be optimized to avoid the defects caused by plasma charging.

  • PDF

FIRST OPERATING TEST OF THE 700 MHz 1 MW PROTOTYPE KLYSTRON FOR A PROTON ACCELERATOR

  • Ko, Seung-Kook;Lee, Bo-Young;Lee, Kang-Ok;Hong, Jin-Seok;Jeon, Jae-Ha;Chung, Bo-Hyun;Noh, Seung-Jeong;Chung, Kie-Hyung
    • Nuclear Engineering and Technology
    • /
    • v.38 no.8
    • /
    • pp.779-784
    • /
    • 2006
  • The design, manufacturing process, and first operating test of a high power RF source for a proton accelerator are described. A klystron amplifier system has been developed for operation at 700 MHz, 1 MW and is composed of a triode type electron gun, six cavities, an RF output window, a beam collector, and an electromagnet. The prototype klystron was constructed and tested at a reduced duty to produce the designed output RF power.

Augmentation Rhinoplasty with Dermofat Graft & Fat Injection (진피지방이식과 지방주입에 의한 비융기수술)

  • Na, Dae-Seung;Jung, Seung-Won;Kook, Kwang-Sik;Lee, Yong-Hae
    • Archives of Plastic Surgery
    • /
    • v.38 no.1
    • /
    • pp.53-62
    • /
    • 2011
  • Purpose: Even though Augmentation rhinoplasty is very popular surgical procedure, it is not easy to obtain ideal materials for augmentation. Many different synthetic materials are used but frequent complications are seen such as infection, extrusion, deform, and dislocation. Autologous tissues were used for augmentation rhinoplasty. We used dermofat graft and fat injection in augmentation rhinoplasty minimizing these problems. Methods: From 2006 to 2009, we used autologous tissues in augmentation rhinoplasty in 40 patients, 20 patients with dermofat graft and other 20 patients were treated with fat injection only. Dermofats were harvested from sacral area. gluteal fold, groin and preexisting scar tissue. Dermofats were inserted with small stab wound and fat tissues were injected as Coleman's technique. The patients were followed up 6 months to 5 years. Results: Most of the patients were satisfied in shape and height the nose. Early complications such as hematoma, infection and seroma were not found. Secondary fat injection was performed in 3 patients (15%) of dermofat graft group instead of 7 patients (35%) of fat injection only group. Conclusion: We obtained satisfactory results in augmentation rhinoplasty with dermofat graft and fat injection. Secondary fat injections were more often in fat injection group than dermofat graft group. Dermofat graft and fat injection could be another alternative technique for augmentation rhinoplasty and fat injection could be a secondary adjunctive treatment for undercorrection due to absorption.

Effect of Organic Acids Fermented from the Settled Sludge and Animal Organic Wastes on the Denitrification (침전 슬러지와 가축분의 유기산화 및 발효유기산이 탈질반응에 미치는 영향)

  • Weon, Seung-Yeon;Park, Seung-Kook;Min, Kyung-Kook;Chung, Keun-Yook;Jun, Byong-Hee;Lee, Sang-Ill
    • Journal of Korean Society on Water Environment
    • /
    • v.21 no.2
    • /
    • pp.147-152
    • /
    • 2005
  • Fermentation efficiencies of organic wastes from the variety of sources were evaluated based on the production of total volatile acids(TVA) in batch reactor. Mixing and pH were not significant factors in producing TVA from the organic wastes. After a 10-day fermentation, final TVA concentrations in piggery, cattle, poultry, and primary settled sludge of domestic wastewater were 8,900, 2,900, 7,370 and 1,630 mg/L, respectively. The pH of organic wastes was decreased from neutral to 5.7. The ratio of TVA to $NH_4{^+}-N$ produced from the animal waste ranged from 11.5 to 30.1, whereas, that in the primary settled sludge of domestic wastewater, was 5.4. Possibility of fermented organic wastes as the electron donors for denitrification in the activated sludge was investigated. In both acclimated and nonacclimated activated sludge, higher denitrification rates were obtained with fermented piggery sludge added than with either methanol or acetate added. The fermented organic acids derived from the primary settled sludge gave the higher denitrification rate ($4.2mg\;NO_3-N/g\;vss{\cdot}hr$) in the acclimated activated sludge. Denitrification rate was $1.5mg\;NO_3-N/g\;vss{\cdot}hr$ in the nonacclimated sludge with the fermented acids from the primary settled sludge of domestic wastewater added.

Parallel Design and Implementation of Shot Boundary Detection Algorithm (샷 경계 탐지 알고리즘의 병렬 설계와 구현)

  • Lee, Joon-Goo;Kim, SeungHyun;You, Byoung-Moon;Hwang, DooSung
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.51 no.2
    • /
    • pp.76-84
    • /
    • 2014
  • As the number of high-density videos increase, parallel processing approaches are necessary to process a large-scale of video data. When a processing method of video data requires thousands of simple operations, GPU-based parallel processing is preferred to CPU-based parallel processing by way of reducing the time and space complexities of a given computation problem. This paper studies the parallel design and implementation of a shot-boundary detection algorithm. The proposed shot-boundary detection algorithm uses pixel brightness comparisons and global histogram data among the blocks of frames, and the computation of these data is characterized with the high parallelism for the related operations. In order to maximize these operations in parallel, the computations of the pixel brightness and histogram are designed in parallel and implemented in NVIDIA GPU. The GPU-based shot detection method is tested with 10 videos from the set of videos in National Archive of Korea. In experiments, the detection rate is similar but the computation time is about 10 time faster to that of the CPU-based algorithm.