Uiler-Lagrange 식을 사용한 확장형 완경사방정식 유도

이창훈(Lee Changhoon),김규한(Kim Kyu-Han) 대한토목학회 2009 대한토목학회논문집 B Vol.29 No.5B

본 연구에서 Euler-Lagrange 식을 사용하여 속도포텐셜로 표현되는 확장형 완경사방정식을 유도하였다. 먼저, Euler-Lagrange 식을 사용하여 흐름함수로 표현된 확장형 완경사방정식을 유도한 Kim과 Bai(2004)의 유도과정을 따라가면서 속도표텐셜로 표현된 확장형 완경사방정식과의 관계를 찾았다. 속도포텐셜로 표현된 Euler-Lagrange 식을 찾아낸 다음 고차의 수심변화 항을 유도하였다. 본 연구에서 유도된 확장형 완경사방정식은 기존의 식인 Massel(1993)의 식과 Chamberlain과 Porter(1995)의 식과 정확히 일치하였다. 본 연구의 연구 성과는 확장형 완경사방정식의 유도 방법을 새로 제시하여 해안공학의 영역을 넓히는데 의의가 있다. In this study, we derive the extended mild-slope equation in terms of the velocity potential using the Euler-Lagrange equation. First, we follow Kim and Bai (2004) who derive the complementary mild-slope equation in terms of the stream function using the Euler-Lagrange equation and we compare their equation to the existing extended mild-slope equations of the velocity potential. Second, we derive the extended mild-slope equation in terms of the velocity potential using the Euler-Lagrange equation. In the developed equation, the higher-order bottom variation terms are newly developed and found to be the same as those of Massel (1993) and Chamberlain and Porter (1995). The present study makes wide the area of coastal engineering by developing the extended mild-slope equation with a way which has never been used before.

Chemoradiotherapy versus radiotherapy alone following induction chemotherapy for elderly patients with stage III lung cancer

Kim, Dong-Yun,Song, Changhoon,Kim, Se Hyun,Kim, Yu Jung,Lee, Jong Seok,Kim, Jae-Sung The Korean Society for Radiation Oncology 2019 Radiation Oncology Journal Vol.37 No.3

Purpose: It is unclear whether adding concurrent chemotherapy (CT) to definitive radiotherapy (RT) following induction CT is a tolerable and cost effective treatment for non-small-cell lung cancer (NSCLC) patients aged 70 years or older with comorbidities. This study evaluated the actual clinical outcomes between concurrent chemoradiotherapy (CCRT) and RT alone following induction CT or not in patients (≥70 years) in a single institution's clinical practice. Materials and Methods: A total of 82 patients with unresectable stage III NSCLC between 2004 and 2016 were retrospectively analyzed. Their treatment tolerance and clinical outcomes such as overall survival (OS), locoregional recurrence (LRR), treatment toxicities and distant metastasis (DM) were evaluated. Early mortality rates were also evaluated as 4-month mortality after RT. Results: Fifty-four patients received CCRT and 28 patients received RT alone. Induction CT before RT was performed for 68.5% and 50.0% in CCRT and RT alone groups. Treatment tolerance was significantly worse in CCRT (p = 0.046). The median survival was 21.1 and 18.1 months for CCRT and RT alone, which was not statistically significant. LRR and DM were also not different. Most early deaths after CCRT were attributed to non-cancer-related mortality. Acute esophagitis of grade ≥2 occurred more following CCRT (p = 0.017). In multivariate analysis, a Charlson Comorbidity Index (CCI) of ≥5 and a weight loss of ≥5% after RT were associated with poor OS. The factors adversely affecting 4-month survival were a CCI of ≥5 and CCRT. Conclusion: There were no significant differences in OS, LRR, and DM between CCRT and RT alone treatment in elderly patients. However, there was a poorer tolerance and higher incidence of acute esophagitis in the CCRT group. Specifically, when the patients had a CCI of ≥5, RT alone seems to be reasonable with a low probability of early death.

Graphene Oxide Assisted Synthesis of Self-assembled Zinc Oxide for Lithium-Ion Battery Anode

Kim, Chungho,Kim, Jin Wook,Kim, Hyunhong,Kim, Dong Hyeon,Choi, Changhoon,Jung, Yoon Seok,Park, Jongnam American Chemical Society 2016 Chemistry of materials Vol.28 No.23

<P>A simple method for the synthesis of a hierarchically self-assembled zinc oxide is presented, in which graphene oxide is used to assist in the assembly of the structure and improve the electrical conductivity of the ZnO. The self-assembled ZnO formed on graphene oxide exhibits a high specific capacity, while also demonstrating good rate performance and cycling stability due to the advantages of using both nanoparticles and a secondary structure.</P>

Progressive Dehazing and Depth Estimation from a Single Hazy Image

Jeonghoon Kim,Sungyoon Kim,Changhoon Pyo,Hyeongmyeon Kim,Changhoon Yim 대한전자공학회 2022 IEIE Transactions on Smart Processing & Computing Vol.11 No.5

We propose a progressive dehazing and depth estimation (PDDE) method with optimal estimation of the attenuation coefficient. We investigated the characteristics of dehazing operations related to the depth and attenuation coefficient for PDDE. Entropy was used as a non-reference image quality metric for optimality assessment of dehazed images. The proposed PDDE method provides an optimal dehazed image and depth estimation from a single hazy image. Experimental results show that the proposed method provides clearer and subjectively better results for single image dehazing than previous image dehazing methods. It also results in a significant improvement in the accuracy of depth estimation from a single hazy image compared with previous depth estimation methods.

블루투스를 이용한 이중인증방식의 전자지불 시스템의 개발

김성일(Sungill Kim),김용민(Yongmin Kim),김현익(Hyunik Kim),정창훈(Changhoon Jung),김응규(Eungkyeu Kim) 한국정보과학회 2004 한국정보과학회 학술발표논문집 Vol.31 No.2Ⅰ

최근 전자상거래의 활성화와 더불어 기존의 유선인터넷에서 사용하고 있는 전자지갑 (S/W)등 전자상거래 방식에서 Smart Cαrd 나 이동통신 단말기와 같은 독립적인 유/ 무선 단일을 사용하는 전자지불 시스템에 대한 관심이 고조되고 있다. 본 연구에서는 전자지불 시스템에 Bluetooth를 이용하여 안전한 사용자 인증 및 종단간의 보안을 제공 전자화폐의 발행/지불이 가능한 전자지불 시스템의 모델을 제시하고자 한다. 각 단일의 서브셋(subset)으로 Bluetooth 컨트롤 시스템과 이를 이용하는 전자지불 시스템으로서 전자지갑 및 전자화폐 발행기/자동판매기를 구현하여 각각의 보안 통신과 전자화폐의 발행/지불이 가능함을 나타냈다. 구현 결과물은 실제 전자지불 시스템에 적용이 가능할 것으로 보인다.

Chemoradiotherapy versus radiotherapy alone following induction chemotherapy for elderly patients with stage III lung cancer

Dong-Yun Kim,Changhoon Song,Se Hyun Kim,Yu Jung Kim,Jong Seok Lee,Jae-Sung Kim 대한방사선종양학회 2019 Radiation Oncology Journal Vol.37 No.3

Purpose: It is unclear whether adding concurrent chemotherapy (CT) to definitive radiotherapy (RT) following induction CT is a tolerable and cost effective treatment for non-small-cell lung cancer (NSCLC) patients aged 70 years or older with comorbidities. This study evaluated the actual clinical outcomes between concurrent chemoradiotherapy (CCRT) and RT alone following induction CT or not in patients (≥70 years) in a single institution’s clinical practice. Materials and Methods: A total of 82 patients with unresectable stage III NSCLC between 2004 and 2016 were retrospectively analyzed. Their treatment tolerance and clinical outcomes such as overall survival (OS), locoregional recurrence (LRR), treatment toxicities and distant metastasis (DM) were evaluated. Early mortality rates were also evaluated as 4-month mortality after RT. Results: Fifty-four patients received CCRT and 28 patients received RT alone. Induction CT before RT was performed for 68.5% and 50.0% in CCRT and RT alone groups. Treatment tolerance was significantly worse in CCRT (p = 0.046). The median survival was 21.1 and 18.1 months for CCRT and RT alone, which was not statistically significant. LRR and DM were also not different. Most early deaths after CCRT were attributed to non-cancer-related mortality. Acute esophagitis of grade ≥2 occurred more following CCRT (p= 0.017). In multivariate analysis, a Charlson Comorbidity Index (CCI) of ≥5 and a weight loss of ≥5% after RT were associated with poor OS. The factors adversely affecting 4-month survival were a CCI of ≥5 and CCRT. Conclusion: There were no significant differences in OS, LRR, and DM between CCRT and RT alone treatment in elderly patients. However, there was a poorer tolerance and higher incidence of acute esophagitis in the CCRT group. Specifically, when the patients had a CCI of ≥5, RT alone seems to be reasonable with a low probability of early death.

시멘트 분진 노출 대상자 분류 모형을 활용하여 미세먼지 노출 연관성 해석

김현진(Hyeonjin Kim),김태우(Taewoo Kim),김우진(Woo Jin Kim),이창훈(Changhoon Lee),최지웅(Jiwoong Choi),김경남(Kyoung-Nam Kim),채금주(Kum Ju Chae),진공용(Gong Yong Jin),이창현(Chang Hyun Lee),최상헌(Sanghun Choi) 대한기계학회 2021 대한기계학회 춘추학술대회 Vol.2021 No.11

New Radome Installation for the TRAO Radio Telescope

Changhoon Lee,Jae Hoon Jung,HyunWoo Kang,Do-Keung Je,Youngung Lee,Il-Gyo Jung,Young Sik Kim,Chang Won Lee,Hyun-Goo Kim 한국천문학회 2017 天文學會報 Vol.42 No.1

Birth of an `Asian cool` reference genome: AK1

( Changhoon Kim ) 생화학분자생물학회(구 한국생화학분자생물학회) 2016 BMB Reports Vol.49 No.12

The human reference genome, maintained by the Genome Reference Consortium, is conceivably the most complete genome assembly ever, since its first construction. It has continually been improved by incorporating corrections made to the previous assemblies, thanks to various technological advances. Many currently-ongoing population sequencing projects have been based on this reference genome, heightening hopes of the development of useful medical applications of genomic information, thanks to the recent maturation of high-throughput sequencing technologies. However, just one reference genome does not fit all the populations across the globe, because of the large diversity in genomic structures and technical limitations inherent to short read sequencing methods. The recent success in de novo construction of the highly contiguous Asian diploid genome AK1, by combining single molecule technologies with routine sequencing data without resorting to traditional clone-by-clone sequencing and physical mapping, reveals the nature of genomic structure variation by detecting thousands of novel structural variations and by finally filling in some of the prior gaps which had persistently remained in the current human reference genome. Now it is expected that the AK1 genome, soon to be paired with more upcoming de novo assembled genomes, will provide a chance to explore what it is really like to use ancestry-specific reference genomes instead of hg19/hg38 for population genomics. This is a major step towards the furthering of genetically-based precision medicine. [BMB Reports 2016; 49(12): 653-654]

Efficacy of Fulvestrant in Heavily Pretreated Postmenopausal Women with Advanced Breast Cancer: A Preliminary Report

Changhoon Yoo,Sung Bae Kim,Jin Hee Ahn,Kyung Hae Jung,Yongchel Ahn,Gyungyub Gong,Hak-Hee Kim,Hee-Jung Kim,손병호,Sei-Hyun Ahn 한국유방암학회 2011 Journal of breast cancer Vol.14 No.2

Purpose: Fulvestrant, a potent estrogen receptor (ER) antagonist with a novel mechanism of action, has shown efficacy in pretreated patients with advanced breast cancer. We assessed the efficacy and tolerability of fulvestrant in Korean postmenopausal women. Methods: Of the 25 candidates identified at Asan Medical Center, Seoul, Korea, six were deemed ineligible due to inadequate baseline and follow-up imaging. The 19 patients included in this retrospective analysis received the approved dose of fulvestrant (250 mg intramuscular injection, once per month) as second- (n=8), third- (n=7), or fourth-line (n=4) endocrine therapy. Results: At a median follow-up of 7.4 months (range, 1.2-34.8 months), the 19 patients received a median of four cycles (range, 1-34 cycles) of fulvestrant. Median time to progression was 5.5 months (95% confidence interval [CI], 0.4-10.7 months), and median overall survival was 17.9 months (95% CI, 2.7-33.1 months). Among 17 evaluable patients, one (5.3%) achieved a partial response, 10 (52.6%) showed stable disease, and six (31.6%) showed progressive disease. The clinical benefit rate was 26.3%. Four patients (21.1%) reported adverse events, but all were grade 1 or 2. Conclusion: Fulvestrant was effective and well tolerated in patients with advanced breast cancer who had been previously treated with several lines of endocrine and chemotherapeutic agents.