특허분석(特許分析)에 의한 폐플라스틱 재활용(再活用) 기술(技術) 동향(動向)

김태현,이강인,김유리,Kim, Tae-Hyun,Rhee, Kang-In,Kim, Yu-Ri 한국자원리싸이클링학회 2010 資源 리싸이클링 Vol.19 No.2

폐플라스틱 관련 재활용 기술 동향을 조사하기 위하여 특허 검색을 실시하였다. 특허 검색 테이터베이스는 국내 WIPS사의 특허 검색 사이트를 이용하였으며, 특허검색범위는 2009년 9월까지 미국, 유럽연합, 일본과 한국에서 출원 및 공개된 특허로 제한하였다. 본 연구에서는 검색된 특허의 요약문을 분석하여 최종 4,795건의 특허를 대상으로 분석하였으며, 폐플라스틱 재활용 기술동향을 연도별, 국가별, 출원인별로 분석하여 조사하였다. 일본의 특허 출원점유율은 65%으로 전체 특허의 과반수 이상을 차지하고 있었으며, 화학적 재활용 기술에 높은 출원 집중률을 보였다. 한국의 경우, 폐플라스틱 재활용 관련 특허는 물질 재활용에 집중되어 있었다. The patents were searched to investigate the trend of recycling technologies about plastic waste. Database was collected from WIPS site and the range of the search was limited to patents opened in U.S.A (US), European Union (EU), Japan (JP) and Korea (KR) to september 2009. In this paper, 4,795 patents were selected by investigation abstracts and the trend of the recycling technologies relating to waste plastic were investigated through the analyzing by the years, countries, companies. The patents were occupied 65% by Japan and the most of the patents were about chemical recycling. In the case of Korea, material recycling was major in the patents of waste plastic recycling.

A Study on Foaming of Polypropylene / EPR System Using Chemical Blowing Agents

김태현,박해영,서관호 ( Tae Hyun Kim,Hae Young Park,Kwan Ho Seo ) 한국공업화학회 1998 한국공업화학회 연구논문 초록집 Vol.1994 No.1

직관적 퍼지 C-평균 모델을 이용한 자기 공명 영상 분할

김태현,박동철,정태경,이윤식,민수영,Kim, Tae-Hyun,Park, Dong-Chul,Jeong, Tai-Kyeong,Lee, Yun-Sik,Min, Soo-Young 한국전기전자학회 2011 전기전자학회논문지 Vol.15 No.3

직관적 퍼지 c-평균 군집화 모델을 이용하는 자기공명 영상의 분할 방법이 본 논문에서 제안되었다. 본 논문에서 채택하는 fuzzy c-means with intuition (FCM-I)은 잡음의 영향을 줄이기 위하여 직관이라는 척도를 사용한다. 실제적 자기 공명 영상에 대해 영상 분할의 실험을 수행하고 기존의 몇몇 군집화 알고리즘과 성능을 비교하였다. 기존의 모델들과 성능을 비교한 결과, FCM-I 기반의 분할 방법은 잡음과 필요한 계수의 선택에 대해 상대적으로 강인하여, 영상 분할에 유용한 모델이 될 수 있음을 확인할 수 있었다. An image segmentation model using fuzzy c-means with intuition (FCM-I) model is proposed for the segmentation of magnetic resonance image in this paper. In FCM-I, a measurement called intuition level is adopted so that the intuition level helps to alleviate the effect of noises. A practical magnetic resonance image data set is used for image segmentation experiment and the performance is compared with those of some conventional algorithms. Results show that the segmentation method based on FCM-I compares favorably to several conventional clustering algorithms. Since FCM-I produces cluster prototypes less sensitive to noises and to the selection of involved parameters than the other algorithms, FCM-I is a good candidate for image segmentation problems.

ELINT 방향탐지 시스템에 적용되는 밀리미터파 대역 레이돔에 대한 실험적 연구

김태현,박범준,이정훈,이병남,Kim, Tae-Hyun,Park, Boem-Jun,Lee, Jung-Hoon,Lee, Byung-Nam 한국군사과학기술학회 2012 한국군사과학기술학회지 Vol.15 No.2

In this paper, we have experimentally studied on phase characteristics of airborne radome for ELINT directional finding system, because it is difficult to find theoretical solutions for phase error of the radome. Especially, we described the millimeter wave band radome that was fabricated with cyanate-ester material and its thickness was 2mm. We presented the phase error about millimeter band radome. That phase error is about 30 degrees for parallel and perpendicular polarization in the K-Ka band. That is reasonable value for the ELINT directional finding system.

'순환골재 품질인증 및 관리에 관한 규칙' 일부 개정

김태현,최원영,Kim, Tae-Hyun,Choi, Won-Young 한국건설순환자원학회 2022 한국건설순환자원학회지 Vol.17 No.1

입체조형 동적회전조사 방사선치료의 선량 검증

김태현,신동호,이두현,박성용,윤명근,신경환,표홍렬,김주영,김대용,조관호,양대식,김철용,Kim Tae Hyun,Shin Dong Ho,Lee Doo Hyun,Park Sung Yong,Yun Myung Guen,Shin Kyung Hwan,Py Hong Ryull,Kim Joo-Young,Kim Dae Yong,Cho Kwan Ho,Yang Dae-Sik,K 한국의학물리학회 2005 의학물리 Vol.16 No.4

입체조형 동적회전조사 방사선치료(Dynamic Conformal Arc Radiotherapy, DCAR)에서 필름 선량계를 이용한 선량검증시 필름 회전중심점 이동 보정값을 최적화법으로 구하고 최적화 후 DCAR에 대한 선량 검증의 정량적 허용기준을 제시하고자 하였다. 정위방사선치료를 시행했던 7명의 전이성 뇌암 환자에서 DCAR 치료계획을 시행하고 필름 선량계로 선량을 측정하였다. 필름 선량계의 가장 큰 계통적 오차 요인인 회전중심점 이동 보정값을 최적화법으로 구하고 치료계획과 필름으로 측정된 선량분포를 비교하여 최적화 전후의 평균 선량오차와 점선량오차가 $5\%$ 이상인 지점의 비율을 얻었다. 모든 환자에서 필름 선량계의 회전중심점 이동 보정값은 1 mm 이내였다. 필름 회전중심점 이동 보정 최적화전, 후로 선량오차 결과를 산출하였다. 최적화 전, 후의 평균 선량오차의 평균은 각각 $1.70{\pm}0.36\%$, $1.34{\pm}0.20\%$이었고 점선량오차가 $5\%$ 이상인 지점 비율의 평균은 각각 $4.54{\pm}3.94\%$, $0.11{\pm}0.12\%$로서 최적화 후 선량오차가 현저히 감소하였다. 본 연구의 결과와 같이 최적화법을 이용한 필름의 회전중심점 이동값을 구하고 최적화 후의 평균 선량오차와 점선량오차가 $5\%$ 이상인 지점의 비율을 구하는 방법은 임상에서 DCAR에 대한 선량 검증 방법으로 유용하게 사용될 수 있을 것으로 기대된다. The purpose of this study is to develop the optimization method for adjusting the film isocenter shift and to suggest the quantitative acceptable criteria for film dosimetry after optimization In the dynamic conformal arc radiation therapy (DCAR). The DCAR planning was peformed In 7 patients with brain metastasis. Both absolute dosimetry with ion chamber and relative film dosimetry were peformed throughout the DCAR using BrainLab's micro-multileaf collimator. An optimization method for obtaining the global minimum was used to adjust for the error in the film isocenter shift, which is the largest pan of systemic errors. The mean of point dose difference between measured value using ion chamber and calculated value acquired from planning system was $0.51{\pm}0.43\%$ and maximum was $1.14\%$ with absolute dosimetry These results were within the AAPM criteria of below $5\%$. The translation values of film isocenter shift with optimization were within ${\pm}$1 mm in all patients. The mean of average dose difference before and after optimization was $1.70{\pm}0.35\%$ and $1.34{\pm}0.20\%$, respectively, and the mean ratios over $5\%$ dose difference was $4.54{\pm}3.94\%$ and $0.11{\pm}0.12\%$, respectively. After optimization, the dose differences decreased dramatically and a ratio over $5\%$ dose difference and average dose difference was less than $2\%$. This optimization method is effective in adjusting the error of the film isocenter shift, which Is the largest part of systemic errors, and the results of this research suggested the quantitative acceptable criteria could be accurate and useful in clinical application of dosimetric verification using film dosimetry as follows; film isocenter shift with optimization should be within ${\pm}$1 mm, and a ratio over $5\%$ dose difference and average dose difference were less than $2\%$.

급수관내 염소 주입이 미생물의 증식과 부식에 미치는 영향

김태현,이윤진,임승주,Kim, Tae-Hyun,Lee, Yoon-Jin,Lim, Seung-Joo 한국환경보건학회 2006 한국환경보건학회지 Vol.32 No.5

This research was conducted using a model home plumbing system composed of copper, stainless steel, galvanized iron, carbon steel, and PVC (polyvinyl chloride) pipe. The number of bacteria present in stainless steel pipe and PVC was higher than other pipes. High turbidity and zinc release were found in galvanized iron pipe material and detected during the first 6 months. Conversely, there was a decrease in turbidity and zinc release after 6 months resulting in levels similar to other pipes. Copper concentration decreased as operation times increased. In this experiment, the number of bacteria detected in biofilm for a copper pipe continued to increase. Pipe material influenced bacterial numbers in biofilm and water. This showed that elevated chlorine could not control bacterial growth in biofilm for galvanized iron and stainless steel systems. It also suggested that the dosing of chlorine might not be available for all kinds of pipes. Therefore, another complementary method should be introduced to manage biofilm effectively in water distribution systems.

액정 전계 렌즈 기반 3차원 디스플레이 장치의 엄정한 시청영역 분석

김태현,김봉식,박우상,Kim, Tae-Hyeon,Kim, Bong-Sik,Park, Woo-Sang 한국전기전자재료학회 2016 전기전자재료학회논문지 Vol.29 No.8

In this paper, we proposed the 3-dimenstional (3D) analysis for calculating the optical characteristics of an autostereoscopic display with electric field driven liquid crystal (ELC) lens. From 3D analysis considering the slanting of lens, we calculate the cross-talk of each images and the distortion of viewing zone. Using geometric opics and extended Jones matrix method (EJMM), phase retardation of ELC lens according to position is calcuated and then optical path difference in 3D space considering tilt and azimuth angle of incident light is gotten. Then, intensity distribution is presented in the space. Through camparing the intensity distribution using ideal lens with the ELC lens, we identify the noise and image distortion of ELC lens. As a result, this analysis is expected to provide optimum design conditions for realistic and rigorous 3D display with ELC lens.

STRUCTURAL ASSESSMENT OF RPV UNDER MULTI-LAYERED CORIUM FORMATION CONDITIONS

김태현,Seung Hyun Kim,장윤석 한국원자력학회 2015 Nuclear Engineering and Technology Vol.47 No.3

External reactor vessel cooling (ERVC) for in-vessel retention (IVR) has been considered one of the most useful strategies to mitigate severe accidents. However, reliability of this common idea is weakened because many studies were focused on critical heat flux whereas there were diverse uncertainties in structural behaviors as well as thermal–hydraulic phenomena. In the present study, several key factors related to molten corium behaviors and thermal characteristics were examined under multi-layered corium formation conditions. Thereafter, systematic finite element analyses and subsequent damage evaluation with varying parameters were performed on a representative reactor pressure vessel (RPV) to figure out the possibility of high temperature induced failures. From the sensitivity analyses, it was proven that the reactor cavity should be flooded up to the top of the metal layer at least for successful accomplishment of the IVR-ERVC strategy. The thermal flux due to corium formation and the relocation time were also identified as crucial parameters. Moreover, three-layered corium formation conditions led to higher maximum von Mises stress values and consequently shorter creep rupture times as well as higher damage factors of the RPV than those obtained from two-layered conditions.

문학교육과 비평인식

김태현,Kim, Tae-Hyeon 한국대학교육협의회 1991 大學敎育 Vol.53 No.-