Three-dimensional analysis of soft and hard tissue changes after mandibular setback surgery in skeletal Class III patients

Park, Jae-Woo,Kim, Nam-Kug,Kim, Myung-Jin,Chang, Young-Il The Korean Association Of Orthodontists 2005 대한치과교정학회지 Vol.35 No.4

하악 수술로 치료한 골격성 3급 부정교합 환자의 연조직 변화를 3차원적으로 분석하였다. 수술전과 수술후에 CT를 촬영하고, 연조직과 경조직을 각각의 임계값에 따라 segmentation였다. FH.평면, 정중시상면, PNS를 포함하는 전두면을 기준으로 공통 좌표계를 구성하고, 이 좌표계를 기준으로 술전, 술후 영상을 위치시켰다. 술후의 변화를 측정하기 위해 각각의 모형에 대해 전두면에 평행한 grid를 형성하였다. Grid내의 교점에서 골조직과 연조직 모형에 투사하여 만나는 점의 좌표값을 구하고, 이를 바탕으로 술후의 변화를 측정하였다. 하악골 후퇴술시 안모의 변화는 하악골 부분에서만 발생한 것이 아니라, 구각부에서도 관찰되었다. 하악골 부위의 연조직 변화는 대응되는 골조직 이동량에 따른 상대적인 값으로 계산하였다. 정중시상면에서의 변화율은 $77\~102\%$로 나타났다. (p<0.05). 정중시상면 이외의 부분의 변화양상도 이와 유사하였다. 구각부에서의 변화는 하악골의 이동을 대표할 수 있는 점의 이동량에 대한 상대적인 값으로 계산하였다. 정중시상면에서의 변화는 B점을 기준으로 $14\~29\%$이고, Pog점을 기준으로 $17\~37\%$, grid상 83번째 점을 기준으로 $11\~22\%$로 관찰되었다.(p<0.05) The three-dimensional (3D) changes of bone, soft tissue and the ratio of soft tissue to bony movement was investigated in 8 skeletal Class III patients treated by mandibular setback surgery. CT scans of each patient at pre- and post-operative states were taken. Each scan was segmented by a threshold value and registered to a universal three-dimensional coordinate system, consisting of an FH plane, a mid-sagittal plane, and a coronal plane defined by PNS. In the study, the grid parallel to the coronal plane was proposed for the comparison of the changes. The bone or soft tissue was intersected by the projected line from each point on the gird. The coordinate values of intersected point were measured and compared between the pre- and post-operative models. The facial surface changes after setback surgery occurred not only in the mandible, but also in the mouth corner region. The soft tissue changes of the mandibular area were measured relatively by the proportional ratios to the bone changes. The ratios at the mid-sagittal plane were $77\~102\%(p<0.05)$. The ratios at all other sagittal planes had similar patterns to the mid-sagittal plane, but with decreased values. And, the changes in the maxillary region were calculated as a ratio, relative to the movement of a point representing a mandibular movement. When B point was used as a representative point, the ratios were $14\~29\%$, and when Pog was used, the ratios were $17\~37\%(9<0.05)$. In case of the 83rd point of the grid, the ratios were $11\~22\%(p<0.05)$.

Projections of summertime ozone concentration over East Asia under multiple IPCC SRES emission scenarios

Lee, Jae-Bum,Cha, Jun-Seok,Hong, Sung-Chul,Choi, Jin-Young,Myoung, Ji-Su,Park, Rokjin J.,Woo, Jung-Hun,Ho, Changhoi,Han, Jin-Seok,Song, Chang-Keun Elsevier 2015 Atmospheric environment Vol.106 No.-

<P><B>Abstract</B></P> <P>We have developed the Integrated Climate and Air Quality Modeling System (ICAMS) through the one-way nesting of global–regional models to examine the changes in the surface ozone concentrations over East Asia under future climate scenarios. Model simulations have been conducted for the present period of 1996–2005 to evaluate the performance of ICAMS. The simulated surface ozone concentrations reproduced the observed monthly mean concentrations at sites in East Asia with high R<SUP>2</SUP> values (0.4–0.9), indicating a successful simulation to capture both spatial and temporal variability. We then performed several model simulations with the six IPCC SRES scenarios (A2, A1B, A1FI, A1T, B1, and B2) for the next three periods, 2016–2025 (the 2020s), 2046–2055 (the 2050s), and 2091–2100 (the 2090s). The model results show that the projected changes of the annual daily mean maximum eight-hour (DM8H) surface ozone concentrations in summertime for East Asia are in the range of 2–8 ppb, −3 to 8 ppb, and −7 to 9 ppb for the 2020s, the 2050s, and the 2090s, respectively, and are primarily determined based on the emission changes of NO<SUB>x</SUB> and NMVOC. The maximum increases in the annual DM8H surface ozone and high-ozone events occur in the 2020s for all scenarios except for A2, implying that the air quality over East Asia is likely to get worse in the near future period (the 2020s) than in the far future periods (the 2050s and the 2090s). The changes in the future environment based on IPCC SRES scenarios would also influence the change in the occurrences of high-concentrations events more greatly than that of the annual DM8H surface ozone concentrations. Sensitivity simulations show that the emissions increase is the key factor in determining future regional surface ozone concentrations in the case of a developing country, China, whereas a developed country, Japan would be influenced more greatly by effects of the regional climate change than the increase in emissions.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Change in ozone level is determined by the combination of NO<SUB>x</SUB> and NMVOC emissions. </LI> <LI> Ozone level over East Asia would get worse in the near future (the 2020s) than far future. </LI> <LI> A high-concentration event generally increases and more frequently occurs in the future. </LI> <LI> Change in ozone air quality in a developing country depends more on emissions change. </LI> <LI> Change in ozone air quality in a developed country depends more on climate change. </LI> </UL> </P>

Investigation of channel mobility in AlGaN/GaN high-electron-mobility transistors

Chang, Sung-Jae,Kang, Hee-Sung,Lee, Jae-Hoon,Yang, Jie,Bhuiyan, Maruf,Jo, Young-Woo,Cui, Sharon,Lee, Jung-Hee,Ma, Tso-Ping Institute of Pure and Applied Physics 2016 Japanese Journal of Applied Physics Vol.55 No.4

<P>We have investigated the channel mobility in the gated region of a set of high-quality AlGaN/GaN high-electron-mobility transistors (HEMTs). The resistances in the contact, access, and gated regions were extracted from straightforward I-D(V-G) measurements on sets of HEMTs with four different gate-to-drain distances. By correcting for the effects of the contact and access resistances, much more accurate effective mobility curves in the gated region, compared to those reported in the past, have been obtained. The maximum effective mobility in that region has been found to be 1100cm(2)V(-1) s(-1) at carrier density n(s) = 7 x 10(12)cm(-2) at room temperature. We have extracted the mobility curves in a wide range of temperatures (80 to 520 K) and carrier concentrations (up to 1.3 x 10(13)cm(-2)). Our systematic measurements have revealed various dominant scattering mechanisms as the temperature and carrier concentration change. (C) 2016 The Japan Society of Applied Physics</P>

수정진동자를 이용한 박막의 상거동 분석

장상목,김종민,이현우,정재헌 동아대학교 공과대학부설 생산기술연구소 1996 生産技術硏究所硏究論文集 Vol.1 No.2

This paper shows that an AT-cut quartz crystal analyzer(Q.C.A) can be applied to the investigation of the microheological change of the polymer blend solution during solvent evaporation process casting blend on the surface of quartz crystal. he blend is made from various compositions of poly(methyl methacrylate) (PMMA) and poly(vinyl acetate)(PVAc), and ethyl acetate as slovent. The resonant frequency and resonant admittance of the blend casting Q.C.A are measured simultaneously and the microheological behavior of the blend is analyzed during ethyl acetate evaporation. The PMMA/PVAc blend solution behaves several informative changes of resonant frequency and resonant admittance during ethyl acetate evaporation, depending on the evaporation time and the blend ratio. The PMMA/PVAc blend solution in ethyl acetate exhibited critical changes of resonant frequency and resonant admittance depending on the evaporation time and blend ratio. From this study, it is known that the quartz crystal analyzer can be successfully applicable to analyze viscoelastic changes on the microrheology and phase separation at the initial stage of the blends of PMMA and PVAc during the solvent, ethyl acetate evaporation process by maesuring the resonant freaquency and the resonant resistance in situ.

서울의 Penicillinase Producing Neisseria gonorrhoeae 발생빈도(1998)

김재홍,김준호,반재용,이정우,황성주,정준규,정성태,강진문,조흔정,홍창의,정혜신,이한승,김이선,이봉길,이종호,선영우,한기덕,윤성필,이성훈,안종성,박석범,문승현,조항래,김형섭,류지호,황재영,박준홍,손상욱 한양대학교 의과대학 2001 한양의대 학술지 Vol.21 No.1

In recent years, gonorrhea has been pandemic and remains one of the most common STDs in the world, especially in developing countries. For the detection of a more effective therapeutic regimen and assessing the prevalence of Penicillinase Producing Neisseria gonorrhoeae(PPNG), we have been trying to study the patients who have visited the Venereal Disease Clinic of Choong-Ku Public Health Center in Seoul since 1980 by menas of the chromogenic cephalosporin method. In 1998, 93 strians of N. genorrhoeae were isolated, among which 60(64.5%) were PPNG. The prevalence of PPNG in Seoul, which had been decreased to 39% in 1996 after a peak of 74.3% in 1993, is increased to 64.5% in 1998.

서울의 Penicillinase Producing Neisseria Gonorrhoeae 발생빈도(1996)

김재홍,황동규,전재홍,김윤석,김중환,김용준,이창균,임동진,김현수,조창근,김경문,박상훈,전우형,김희성,이호정,차명수,김갑형,김형석,김석우,황지환,박병순,권오상,이민수,송기훈,성소영,이인섭,부태성 대한화학요법학회 1999 대한화학요법학회지 Vol.17 No.2

Background : In recent years, gonorrhea has been panedemic and remains one of the most commom STDs in the world, especially in developing countries. Objective & Methods: For the detection of a more effective therapeutic regimen and assessing the prevalence of PPNG, we have been trying to study the patients who have visited the VD Clinic of Choong-Ku Public Health Center in Seoul since 1980 by means of the chromogenic cephalosporin method. Results: In 1996, 139 strains of N. gonorrhoeae were isolated, among which 53(39.0%) were PPNG. Conclusion: Our results suggests that after a peak of 74.3% in 1993, the prevalence of PPNG in Seoul is gradually declining.

이상기후 발생이 가을배추 생산자 및 소비자에게 미치는 영향

조재환 ( Jae Hwan Cho ),서정민 ( Jeong Min Suh ),강점순 ( Jum Soon Kang ),홍창오 ( Chang Oh Hong ),신현무 ( Hyun Moo Shin ),이상규 ( Sang Gyu Lee ),임우택 ( Woo Taik Lim ) 한국환경과학회 2013 한국환경과학회지 Vol.22 No.12

The purpose of this article is analyzing the economic impacts of abnormal climate on fall chinese cabbage farmers and consumers in Korea, with employing the equilibrium displacement model. Our results show that there were little difference in gross farm income, even though there were significant yield reductions due to abnormal climate changes. However periodic occurrences of abnormal climates caused serious damage to consumption levels which had declined by 10.6~17.1 percent with higher prices by 15.3~24.6 percent than normal climate years since 1990.

空氣壓 변화에 의한 실린더의 最適 位置制御에 관한 硏究

박창언,김일수,김기우,정영재,손준식,송창재 木浦大學校 工業技術硏究所 1999 工業技術硏究誌 Vol.9 No.-

With the increasingly strict demands on accuracy position control of the production line, the modelling and control of the activated process have become a subject of great interest. Much efforts have been made in understanding and modelling of this process in the last decade. This thesis concentrates on the position control of Pneumatic cylinder under parameter variation. An adaptive control is proposed to design the defferent controllers(P, PI, PID, PD controller) in order to choose the best controller based on the fast and accurate control of the system. It is shown that the adaptive control algorithm is robust and effective in attaining the fast and accurate position control of system under time-dependent parameter variation. Experimental results showed that PD controller law is effective to obtain the fast response and to increase the stability of the system. The method is a useful control algorithm which always automatically adjusts the position control in accordance with the error, using carrier wave of triangle type regardless of changes on the operating condition and physical differences between components.

EBS 방송 시청이 인문계 고등학생의 사교육비 지출에 미치는 영향

장지윤(Jee-yun Chang),박인우(Inn-woo Park),장재홍(Jae-hong Jang) 중앙대학교 한국교육문제연구소 2017 한국교육문제연구 Vol.35 No.3

본 연구는 2013년부터 2015년까지 서울지역 인문계 고등학생의 EBS 방송 시청이 사교육비 지출에 미치는 영향을 각 학년 시점에 따라 분석하고, 사교육비 지출의 초기값과 변화율에 영향을 미치는 관련 변인(초기학업성취도, 월평균 가계소득, 대학진학계획)들을 설정하여 영향력을 분석하였다. 이를 위해 서울 소재 인문계 고등학교 학생 3,017명을 대상으로 고등학교 1학년부터 3학년까지 추적·조사된 서울교육종단연구의 4차년도(2013년)~6차년도(2015) 데이터를 활용하였으며 잠재성장모형(Latent Growth Model)을 적용하여 종단자료의 시간에 따른 변화를 파악하였다. 연구결과 첫째, 학년이 올라갈수록 사교육비 지출이 지속적으로 증가하는 것으로 나타났다. 또한, EBS 방송 시청시간 역시 학년이 증가할수록 늘어나고 있다. 둘째, EBS 방송 시청은 고등학교 3학년 학생의 사교육비 지출 감소에 가장 많은 영향을 미치는 것으로 나타났다. 셋째, 초기학업성취도와 월평균 가계소득은 사교육비 지출의 초기값에 유의미한 영향을 주는 것으로 나타났다. 또한 월평균 가계소득은 사교육비 지출 변화율에도 유의미한 영향을 주는 것을 확인하였다. 본 연구는 EBS 방송의 사교육비 경감 효과를 지속적으로 확인하는데 의의가 있으며, 학년에 따른 분석 및 검증을 통한 정책적 제언을 바탕으로 향후 논의될 EBS-수능 연계 정책의 개선방향 및 EBS 방송 콘텐츠 개발 방향 수립에 기여하고자 한다. The purpose of this study was to analyze the effect of watching EBS broadcasting of general high school students in Seoul from 2013 to 2015 on private tutoring expenditure according to each grade. For this study, 3,017 students of general high school in Seoul(SELS; Seoul Education Longitudinal Study) were used. These data were measured from the first grade to the third grade in general high school. Also, the Latent Growth Model was applied to analyze the effect of the variables as time changes. The results of the study are as follows. First, as the grade rises, spending on private tutoring expenditure increases steadily. Also, time spent watching EBS broadcasting increases as the grade level increases. Second, watching EBS broadcasting showed the greatest effect on the decrease of private tutoring expenditure by the third grade students in general high school. Third, initial academic achievement and monthly average household income have a significant effect on the base year of private tutoring expenditure. In addition, the monthly average household income has a significant effect on the rate of change of private tutoring expenditure. This study can be used as a basis for judging the effectiveness of EBS broadcasting, the effect of reducing the private tutoring expenditure of each grade. and to identify the variables that affect private tutoring expenditure. Based on the results of this study, implications and suggestions are discussed.

Endoscopy and Imaging Modalities/Basic Science of Gastrointestinal Disorders/Miscellaneous : Changing Pattern Of Digestive And Liver Disease In Korea, 1990-2006 Year; A Single Center Study

( Jung Hyun Kwon ),( Sang Woo Kim ),( In Sik Chung ),( Myung Gyu Choi ),( Kwan Woo Nam ),( Jung Pil Suh ),( Jae Hyuck Chang ),( Won Haing Hur ),( Yu Kyung Cho ),( Jae Myung Park ),( In Seok Lee ) 대한소화기학회 2007 SIDDS Vol.9 No.-

Background/Aims: Westernization in many Asian countries have changed lifestyles and diets, so once rare diseases have now become prevalent. The aim of this study is to investigate the changing pattern of digestive and liver disease in Korea, from 1990 to 2006. Methods: We extracted data specific gastrointestina (GI) disease based on the International Classification of Diseases code from the in-patients records at the Kangnam St. Mary`s Hospital in 1990, 1996 and 2006. This hospital is a tertiary-care hospital in Seoul, Korea, which has a capacity of 800 beds. Results: The admission rate for GI disease increased between 1990 and 2006. Overall in-patients were 1,623 persons in 1990, 2,368 persons in 1996 and 4,166 persons in 2006. The mean age of in-patients increased as time went by. A stomach cancer was the most common diagnosis during all periods, but its prevalence has decreased. Colon cancer ranked the 7th in 1990, but markedly increased and now ranks the second. The third was a hepatocellular carcinoma. The bile duct and gallbladder cancer, pancreas and esophageal cancer ranking followed with little interval change. In cases of cancer patients, a regular admission dramatically increased for chemotherapy. The number of patients admitted with pre-malignant neoplasm of stomach and colon increased remarkably with the development of endoscopy. The liver transplant, inflammatory bowel discase, and reflux esophagitis emerged form mid-1990s with greater frequencies, yet much below the levels found in the West. The admission rate for peptic ulcer, especially ulcer bleeding remained relatively stable, despite a decreased rate for ulcer perforation. Liver cirrhosis, hepatitis, cholelithiasis with cholecystitis-cholangitis, appendicitis, hemorrhoid and gastritis all decreased. Conclusions: The stomach cancer is the leading cause of admission, despite a recent decline. Colon cancer showed a marked rise. The liver transplant, inflammatory bowel disease and reflux esophagitis were new diagnosis with an increased tendency.