톱니상 폴립의 내시경적 진단, 치료와 추적 관리

김덕환,Duk Hwan Kim 대한소화기암연구학회 2023 Journal of digestive cancer reports Vol.11 No.1

Since the 1990s, serrated polyps have been established to contribute to intermediate cancer development, and their importance has begun to be recognized. Serrated polyps are morphologically difficult to detect through endoscopy, and an effective resection method has not been established. Among serrated polyps, studies on sessile serrated lesions, with a relatively high risk of colorectal cancer transformation and detected with difficulty, are in progress. Studies to date describe the endoscopic features as mucus cap, surface debris or stool, attenuation of underlying vasculature, cloud-like surface, dark spots in crypts, and ill-defined irregular border. Additionally, it is expected that relatively large serrated polyps can be safely removed through cold snare resection. A plan for an effective management of serrated polyps through continuous research in the future is warranted.

한반도 연속호우 발생 사례 및 전망 분석

김덕환,한대건,김형수,Kim, Deok-Hwan,Han, Dae-Geon,Kim, Hyeong-Su 한국수자원학회 2018 물과 미래(한국수자원학회지) Vol.51 No.10

일본의 가축공제제도 소개

김덕환,김두,Kim, Deok-Hwan,Kim, Du 대한수의사회 2006 대한수의사회지 Vol.42 No.10

$xMgTiO_3$(1-x) ($Na_{1/2}Ln_{1/2}$) $TiO_3$(Ln = La, Pr, Nd, Sm)의 초고주파 유전특성에 관한 연구

김덕환,임상규,안철,Kim, Duck-Hwan,Lim, Sang-Kyu,An, Chul 대한전자공학회 1998 電子工學會論文誌, D Vol.d35 No.10

(Na½Ln½) TiO₃(Ln = La, Pr, Nd, Sm)은 양의 온도계수(190 ∼ 480ppm/℃), 고유전율(99∼127)의 특성을 갖고 있다. 반면에 MgTiO₃는 음의 온도계수(-45ppm/℃), 저유전손실(110,000㎓)을 갖고 있다. 그래서 xMgTiO₃(1-x) (Na½Ln½) TiO₃의 유전특성에 관심을 갖게 되었고, 초고주파 대역에서의 유전특성을 측정하고 미세구조를 관찰하여, 몰비변화와 소결온도변화에 따른 경향성을 파악하였으며, 그 원인을 연구하였다. 그 결과 MgTiO₃와 (Na½Ln½) TiO₃는 구조적으로 새로운 고용체나 이차상을 형성하지 않는 혼합상을 이루고 있었다. 그리고 이들의 유전특성은 (Na½Ln½) TiO₃와 MgTiO₃의 중간 값을 나타냈고, logarithmic mixing rule로써 유전특성을 예측할 수 있다. 이중에서 온도에 안정한 조성은 Ln = La, Pr, Nd으로 치환되었을 경우 각각 x = 0.9, 0.87, 0.84이었다. 이때의 유전율은 22 ∼25, Qf값은 55000 ∼ 28000㎓를 나타내었다. 이로써 온도에 안정한 유전특성을 갖는 새로운 유전체 재료를 개발하였으며, 특히 Ln = La으로 치환되었을 경우 다른 조성에 비하여 유전특성이 좋을 뿐아니라, 소결온도 범위가 넓어 공정상의 잇점을 가지고 있다. ($Na_{1/2}Ln_{1/2}$)$TiO_3$ceramics have a high relative dielectric constant and a positive temperature coefficient of resonant frequency ($\tau_f$)(where Ln represents a lanthanide: $La^{+3}$, $Pr^{+3}$, $Nd^{+3}$ and $Sm^{+3}$). On the other hand, $MgTiO_3$ ceramic has a high Qf value and a negative temperature coefficient. So We have investigated the microwave dielectric properties of $xMgTiO_3$-(1-x) ($Na_{1/2}Ln_{1/2}$)$TiO_3$. In these systems, there are no clues on solid-solution and secondary phase. There are mixed phases with $MgTiO_3$and ($Na_{1/2}Ln_{1/2}$)$TiO_3$ phases. Its dielectric characteristics (Qf, temperature coefficient and dielectric constant) are intermediate between ($Na_{1/2}Ln_{1/2}$)$TiO_3$ and $MgTiO_3$ and are predictable by the logarithmic mixing rule. The dielectric ceramic compositions temperature coefficient each approximates to zero at Ln=La, x=0.9, Ln=Pr, x=0.87, and Ln=Nd, x=0.84. At this time, there are Qf values in the range of 55,000 to 28,00GHz and relative dielectric constants in the range of 22 to 25.

사용자 선호도와 시각적 기술자를 이용한 사용자 프로파일 기반 이미지 추천 알고리즘

김덕환,양준식,조원희,Kim, Deok-Hwan,Yang, Jun-Sik,Cho, Won-Hee 한국정보처리학회 2008 정보처리학회논문지D Vol.15 No.4

정보 기술과 인터넷의 발전은 멀티미디어 컨텐츠의 양에 있어서 폭발적인 성장을 가져 왔으며 이러한 멀티미디어 컨텐츠 양의 증가는 이용자의 요구에 맞는 멀티미디어 컨텐츠 추천에 대한 필요성을 더 증가 시켰다. 현재까지 일반상품과 멀티미디어 컨텐츠 추천을 위한 기법에는 협업필터링 (CF: Collaborative Filtering)이 있다. 하지만 기존의 CF 기법은 이미지가 갖고 있는 시각적 특징을 제대로 표현하지 못하고 있으며, 입력 데이터의 희박성 (Sparsity) 문제와 신상품 추천 문제 그리고 선호도의 동적인 변화 문제를 포함하고 있기 때문에 이미지 컨텐츠 추천에는 적합하지 않다. 이와 같은 기존의 CF기법의 단점을 해결하기 위해서 본 논문에서는 새로운 이미지 추천 방법으로 FBCF (Feature Based Collaborative Filtering) 기법을 제안한다. FBCF 기법은 시각적 특징을 선호도에 따라 군집화한 새로운 사용자 프로파일 구성방법을 제시하며, 선호도 피드백을 통하여 구매자의 현재 성향을 추천에 반영할 수 있다. 실제 모바일 이미지 데이터를 사용한 실험에서 FBCF 기법이 기존의 CF 기법보다 400% 향상된 성능을 보임을 확인할 수 있다. The advancement of information technology and the popularization of Internet has explosively increased the amount of multimedia contents. Therefore, the requirement of multimedia recommendation to satisfy a user's needs increases fastly. Up to now, CF is used to recommend general items and multimedia contents. However, general CF doesn't reflect visual characteristics of image contents so that it can't be adaptable to image recommendation. Besides, it has limitations in new item recommendation, the sparsity problem, and dynamic change of user preference. In this paper, we present new image recommendation method FBCF (Feature Based Collaborative Filtering) to resolve such problems. FBCF builds new user profile by clustering visual features in terms of user preference, and reflects user's current preference to recommendation by using preference feedback. Experimental result using real mobile images demonstrate that FBCF outperforms conventional CF by 400% in terms of recommendation ratio.

우백혈병의 임상 및 세포형태학적 연구

김덕환,Kim Duck-Hwan 한국임상수의학회 1985 한국임상수의학회지 Vol.2 No.1

Clinical and cytomorphological studies were carried out in 32 leukotic cattle from Tokachi and Kushiro districts in Hokkaido during the 12 year period from 1969 to 1980. The leukotic cattle were examined :and divided into four types(15 cases of the adult, 11 cases of the thymic, 4 casas of the calf and 2 cases of the skin types). The results obtained were as follows : 1. As for the frequency of the main clinical signs in each type, In the adult type, the main clinical signs (of decreasing order) are as follows: swelling of the superficial lymph nodes>depression and loss of weight>tachycardia>anorekia, anemia of the visible mucous membrane and tachypnea. Those of the thymic type were swelling of the thymus>swelling of the medial iliac lymph nodes> swelling of the superficial lymph nodes>tachypnea. Those of the calf type were swelling of the auperficial lymph nodes>depression and emaciation>tachypnea>anorexia, tachycardia, anemia of the visible mucous membrane and recumbency. Those of the skin type were generalized urticaria-like lesions in skin and swelling of superficial lymph nodes>and depression and loss of weight in the decreasing order of frequency. In addition, large tumor mass in the pelvic cavity and swelling of the medial iliac lymph nodes were detected through rectal palpation in 33.3% and 100% in the adult type cases, respectively. 2. As for the hematological findings, The frequency of occurrence of decreased erythrocyte counts in the decreasing order were as follows : adult>calf>thymic>and skin types. The increase in the total leukocyte count in the order of decreasing frequency were as follows: calf>thymic>adult>and skin types. The increase in the absolute lymphocyte counts was found to be at a low rate, 62.5% of all the cases examined. By contrast, the increase of 5% or more of abnormal lymphocyte rates was observed at a high rate, 96.9% of the total cases. 3. Abnormal lymphocytes were found in all cases examined for lymph nodes biopsied. 4. From the cytomorphological point of view, leukotic cells were divided into 3 types: reticulum cell, lymphoid cell and monocytic cell types. The adult type leukotic cattle were divided with reticulum cell type (66.7%), the lymphoid cell type(22.6%) and monocytic cell type(6.7%). The thymic type was lymphoip cell type(72.7%) and reticulum cell type(27.3%). In the calf type, all were lymphoid cell type while all of the skin type were reticulum cell type only. 5. The leukotic cattle had higher NP frequency in the blood and lymphoid tissue than non-1 eukotic cattle. Especially the adult type had the highest NP frequency. However, it was not recognized that NP were characteristic of leukotic cattle alone. 6. The above findings lead to the conclusion that the most effective diagnostic methods for bovine leukosis are the confirmation of swelling of the superficial and internal lymph nodes and thymus in addition to appearance of abnormal neoplastic cell in the peripheral blood and lymph nodes biopsied.

세퍼드 잡종견에 발생한 복합적 선천성 심장기형의 일예

김덕환,김교준,권오덕,전무형,박청희,이병철,최희인,박경수,Kim Duck-Hwan,Kim Kyo-Joon,Kwon Oh-Deog,Jun Moo-Hyung,Park Chung-Hee,Lee Byung-Chul,Choi Hi-In,Park Kyung-Soo 한국임상수의학회 1988 한국임상수의학회지 Vol.5 No.2

One four-month-old female shepherd mongrel dog with chief complaints of abdominal distension and dysponea was referred. The authors performed physical examination, hematological examination, X-ray examination, exploratory laparotomy, electrocardiography and angiography as antemortem investigation in addition to postmortem examination. This patient revealed complicated congenital cardiac anormaly including patent ductus arteriosus, both atrial and ventricular hypertrophy, distension in the base of the pulmonary artery, pulmonary stenosis, aortic insufficiency, patent foramen ovate and coronary arteriovenous fistula.

반추수의 창상성심낭염의 진단에 관한 연구 II. 인공유발 창상성심낭염에 있어서 LDH 총활성 및 LDH isoenzyme의 변화

김덕환,김교준,전무형,권오덕,윤상보,이창우,Kim Duck-Hwan,Kim Kyo-Joon,Jun Moo-Hyung,Kwon Oh-Deog,Yoon Sang-Bo,Lee Chang-Woo 한국임상수의학회 1988 한국임상수의학회지 Vol.5 No.2

To develop more reliable diagnostic measures for traumatic pericarditis in ruminant, fluctuations of serum total LDH activities and LDH isoenzymes fractions were investigated in artificially induced pericarditis of Korean native goats. Experimental group showed the tendency of increase serum LDH total activities. Effect of LDH isoenzymes on serum total LDH activities were high with decreasing order of LDH$_1$> LDH$_3$ > LDH$\sub$5/ > LDH$_2$ > LDH$_4$ and LDH$_1$ was the hightest among them. From these findings, increase of serum total LDH activities and LDH$_1$ fraction was thought to be important in traumatic pericarditis.

개 임파육종의 치료시험

김덕환,김교준,전무형,권오덕,Kim Duck-hwan,Kim Kyo-joon,Jun Moo-hyung,Kwon Oh-deog 대한수의사회 1988 대한수의사회지 Vol.24 No.1

An attempt to treat canine lymphosarcoma with the combination chemotherapy protocol consisting of cyclophosphamide, vincristine, L-asparaginase and methotrexate was made for 3 weeks. The chemotherapy to the patient showed good responses such as better cha

개의 임파육종의 1예

김덕환,김교준,조성환,전무형,권오덕,배규열,이영순,Kim Duck-Hwan,Kim Kyo-Joon,Cho Sung-Whan,Jun Moo-Hyung,Kwon Oh-Deog,Bae Kyu-Yul,Lee Yong-Sun 한국임상수의학회 1986 한국임상수의학회지 Vol.3 No.2

One six-year-old male Cocker spaniel with chief complaints of mandibular swelling and anorexia was referred. This dog was diagnosed into lymphosarcoma by the results of the examination with peripheral blood and fluid of the lymph nodes and bone marrow aspirated. This patient was multicentric form clinically and was cytomorphologically identified into lymphoblastic form of lymphosarcoma.