수직자기기록용 박막의 제작

김경환,김명호,손인환,김재환 ( Kyung Hwan Kim,Myung Ho Kim,In Hwan Son,Jae Hwan Kim ) 한국전기전자재료학회 1997 한국전기전자재료학회 추계학술대회논문집 Vol.1997 No.1

베체트씨병에 의한 대동맥판 폐쇄부전의 수술적 치료

김경환,김기봉,김원곤,김주현,안혁,Kim, Kyung-Hwan,Kim, Ki-Bong,Kim, Won-Gon,Kim, Joo-Hyun,Ahn, Hyuk 대한흉부심장혈관외과학회 2000 Journal of Chest Surgery (J Chest Surg) Vol.33 No.5

Background: Cardiac involvement of Behcets disease is very rate, however, the prognosis of Behcet disease depends on cardiovascular complications. In this article, we described surgical treatment of aortic insufficiency with Behcets disease. Material and Method: From March 1986 to February 1998, we operated on 10 patients of aortic insufficiency with Behcets disease. Male to female ratio was 8 to 2, and age ranged from 21 to 40 years(mean 32.8 years). There were 8 patients with evidence of Behcets disease and another 2 patients had some suspicious findings of Behcets disease(i.e., prosthetic value dehiscence, hypertrophied aortic wall). Adequate preoperative medical treatment for Behcets disease was done in 3 patients. Result: We performed 24 open heart surgeries in 10 patients. Redo value replacements using prosthetic valves were done in 4 patients. Among them, 2 patients were operated on for a second redo valve replacement and one of them operated on for a 4th and 5th operation because of recurrent paravalvular leakage. These 4 patients expired. 1 patient who had undergons tissue value replacement is alive. 1 patient who underwent Cabrol operation expired dut to rupture of graft anastomosis site. We used homografts in 3 patients. In 2 of them, we performed aortic root replacement and subcoronary valve replacement in another patient. The patient who underwent subcoronary valve insertion had remnant aortic insufficiency, so we are closely observing him. We also performed Ross operation in a 24 year old female who suffered severs aortic insufficiency and endocarditis after aortic valvuloplasty. 5 patients are alive and mean follow up duration is 49.0 months. Among them, we used homografts or sutografts in 4 patients. We could observe excellent clinical results in the patients who underwent aortic root replacement using homograft and they were treated medically for Behcets disease. Conclusion: We concluded that adequate preporative diagnosis, clinical suspicion, and periopertive medical treatment for Behcets disease are very important for the result of surgical management of aortic insufficiency with Behcets disease. The use of homograft or autograft was helpful for the healing of anastomosis site and we should carefully observe the long term follow up results.

CPM Bar Chart 기법을 활용한 일정계획

김경환,김수유,김재준,Kim Kyung-Hwan,Kim Soo-Yoo,Kim Jae-Jun 한국건설관리학회 2004 건설관리 : 한국건설관리학회 학회지 Vol.5 No.5

본 연구에서는 바차트(bar chart) 기법과 CPM 기법의 장점을 결합한 CPM bar chart(CBC) 기법을 제시한다. CBC는 기존의 fenced bar chart(FBC)의 장점을 유지하면서 단점을 보완한 것으로, 작업 관계를 나타내는 fence에 방향성을 부여함으로써, 기존 FBC에서 상당한 혼란을 유발하는 fence의 분리과정 없이 작업들의 관계를 표현할 수 있다. 또한, fence의 분리를 파악하기 위해 더미작업(dummy activity)을 확인하는 과정이 생략되어 보다 손쉽게 작성할 수 있는 장점도 있다. 바차트의 간결성을 유지하면서 CPM의 네트워크 논리 표현이 가능해짐에 따라, CBC는 다양한 프로젝트 참여자들 간의 원활한 의사소통에 기여하리라 예상된다. 또한, resource constrained scheduling, resource leveling, 작업 분리가 고려된 일정 조정, 공기 지연 분석 등의 CPM 기법에 기초한 다양한 일정 계획 및 관리에도 적용이 용이하여, 실무뿐만이 아니라 공정관리 교육과정에서도 활용성이 높으리라 기대된다. This paper proposes the CPM bar chart (CBC), a hybrid of the bar chart and the critical pad method (CPM). The CBC overcomes shortages of the fenced bar chart, while still keeping advantages. The fence with direction is applied instead of the broken fence, which triggers considerable problems to identify and apply in the fenced bar chart. In addition, the notorious task to find dummy activities is no longer required. Upon the benefits of simplicity in the bar chart and logical work sequence in the CPM network. the CBC provides a relatively easy way to create and understand a schedule, thus improving communication quality between project participants. With the advantages, the CBC can also be effectively applied to various scheduling techniques such as resource constrained scheduling, resource leveling, scheduling with activity split, delay impact analysis, etc.

고양지역 두 병원에서의 약물 중독 양상

김경환,박준석,신동운,노준영,김혜진,구홍두,조진경,김아진,Kim Kyung-Hwan,Park Jun-Soek,Shin Dong-Wun,Rho Jun-Young,Kim Hey-Jin,Gu Hong-Du,Cho Jin-Kyung,Kim Ah-Jin 대한임상독성학회 2006 대한임상독성학회지 Vol.4 No.1

Purpose: In the year of 2005, it enforced the basic study for establishing program of Poison Control Center by National Institute of Toxicologic Research. The object of our survey is to analyze the characteristics of intoxication from the City of Goyang by same protocol. Methods: We retrospectively reviewed the data of medical records of the intoxication patient in the two hospitals of the Goyang from 2004 June 1st to 2005 May 31th. The investigation protocol applied the TESS report form which was used from the Basic study for establishing program of Poison Control Center. Results: The intoxication patients were total 269 persons, the patients of A hospital were 184 persons, B hospital were 185 persons. The most common intoxication materials were medicines, in afterwords it was an agricultural chemical. The most common place of intoxication was the home. The intentional suicidal attempts in the reason of intoxication were 51.2%. The rate of the patients who discharges from the emergency department was 50.4% and death rate was 4.3%. Conclusion: We concluded that the continuous and systemic report and analysis should be accomplished from the Goyang area.

대한민국 흉부외과 수술자료수집을 위한 코드

김경환,김광택,노환규,박승일,박영환,선경,성숙환,송현,심영목,원태희,임청,이정렬,정경영,전태국,박수정,Kim, Kyung-Hwan,Kim, Kwang-Taek,Rho, Hwan-Kyu,Park, Seung-Il,Park, Young-Hwan,Sun, Kyung,Sung, Sook-Hwan,Song, Hyun,Shim, Young-Mok,Won, Tae-He 대한흉부심장혈관외과학회 2001 Journal of Chest Surgery (J Chest Surg) Vol.34 No.1

앉고 일어서기 동작에서 점진적 체중 이동을 이용한 시각적 되먹임 훈련이 만성 편마비 환자의 균형 및 보행능력에 미치는 영향

김경환,박성훈,김형민,박노욱,김다연,Kim, Kyung-hwan,Park, Sung-hoon,Kim, Hyung-min,Pak, Noh-wook,Kim, Da-yeon 대한고유수용성신경근촉진법학회 2017 PNF and Movement Vol.15 No.1

Purpose: This study aimed to investigate the effect of visual feedback training-for gradual weight shift in sit-to-stand training-on the balance and walking abilities of chronic hemiplegia patients. Methods: Twenty patients with chronic hemiplegia volunteered to participate in this study. The experimental group received visual feedback for gradual weight shift in the sit-to-stand training, while the contrast group followed the standard process for the sit-to-stand training. The evaluation of the balance and walking ability was conducted with the functional reach test (FRT), Berg balance scale (BBS), five time sit-to-stand (FTSTS) test, timed up and go (TUG) test, 10 m walk test (10MWT), balancia, activities-specific balance confidence (ABC) scale, and falls efficacy scale (FES). Results: In the results before and after intervention, there was a significant difference in TUG, 10MWT, ABC, and FES in the visual feedback training group (p < 0.05). In the control group, there was a significant difference in the 10MWT and ABC (p < 0.05). Also, in the evaluation of the postural fluctuations, the control group data showed a significant increase in Covar. The visual feedback group showed a significant difference in the W average. Conclusion: The visual feedback training group showed some improvement in terms balance and walking ability and on the ABC scale and FES. Therefore, if the diagonal progressive weight bearing exercise is combined with the various patterns and basic principles of PNF, it may be a more efficient intervention method.

알루미늄 엣칭부산물을 첨가한 CPE 고무재료의 난연성 및 내열성 연구

김경환,이창섭,Kim, Kyung Hwan,Lee, Chang Seop 대한화학회 2001 대한화학회지 Vol.45 No.4

자동차 Oil cooler용 호스를 구성하는 클로로폴리에틸렌(CPE) 고무재료의 내열 및 난연성을 향상시키기 위하여 수산화알루미늄을 내열 및 난연제로 제조한 배합고무의 가황틀성, 물리적 성질, 내열성, 난연성을 조사하였으며, 실험결과로부터 고무와 난연제의 최적배합조건을 도출하였다. 고무시편을 제조하는데 사용된 고무재료는 화학적 내식성과 내한성이 우수하면서도 가격이 저렴한 클로로폴리에틸렌 고무를 사용하였으며, 내열 및 난연제로서는 알루미늄 표면 처리과정에서 발생되는 에칭부산물을 분쇄와 정제를 거쳐 가공한 수산화알루미늄을 사용하였고, 분말은 XRD(X-ray diffraction), PSA(Particle Size Analysis), SEM(Scanning Electron Microscopy) 및 ICP-AES(Inductively Coupled Plasma-Atomic Emission Spectroscopy)로 입자의 상, 크기, 분포, 형태 및 성분을 분석한 후 CPE 고무재료와 0∼80 phr범위에서 훈련하였다. CPE배합 고무의 경도, 인장강도, 신장율, 인장응력 및 열적특성을 분석한 결과, 고무재료규격을 초과하지 않는 범위 내에서 최대의 내열 및 난연효과를 주는 수산화알루미늄의 첨가량은 40 phr로 나타났으며, 이 배합비에서 클로로폴리에틸렌의 난연성은 3배 향상되었다. Aluminum Hydroxide was employed as a thermal retardent and flame retardent for Chloropolyethylene (CPE) rubbery materials which is the construction material of automotive oil cooler hose. and then cure characteristics, physical properties, thermal resistance and flame retardation of compounded rubber were investigated, and optimum mixing conditions of rubber and flame retarding agent were deduced from the experimental results. CPE rubber material which has excellent properties of chemical corrosion resistance and cold resistance and inexpensive in price was used to prepare rubber specimen. The by-product of ething, produced from the process of surface treatment of aluminum was processed to aluminum hydroxide via crushing and purification, which is characterized by XRD, PSA, SEM and ICP-AES techniques in terms of phase, size, distribution, morphology and components of particles and then mixed to CPE rubber materials in the range of 0~80 phr. Hardness, tensile strength, elongation and thermal properties of compounded rubber specimens were tested. The optimum mixing ratio of rubber to additives to give maximum effect on thermal resistance and flame retardation, within the range of tolerable specification for rubber materials, was determined to be 40 phr. The flame retardation of CPE rubber materials was found to be increased by 5 times at this mixing ratio.

심장판막 치환술을 병행한 관상동맥 질환의 수술

김경환,채헌,노준량,Kim, Kyung-Hwan,Chae, Hurn,Rho, Joon-Ryang 대한흉부심장혈관외과학회 1994 Journal of Chest Surgery (J Chest Surg) Vol.27 No.3

Between March, 1989, and August, 1993, 10 patients underwent aortocoronary bypass surgery concomittant with cardiac valve replacement. They were 6 men and 4 women, the age ranging from 47 to 64. 7 patients underwent single valve replacement and 2 patients underwent double valve replacement, Another one patient underwent only CABG one year after valve replacement and he had no evidence of prosthetic valve failure. Total number of graft vessels were.15,14 were saphenous venous grafts and 1 was internal mammary artery graft. Dyspnea on exertion was frequent symptom and was found in all patients. 8 patients presented stable angina, only 1 patient presented postinfarct angina and another 1 patient presented no angina symptom. The graft was placed prior to valve replacement and periods of myocardial ischemia were kept at a minimum by maintaining coronary perfusion throughout operation. Postoperative course was uneventful and there was no hospital mortality, as was supported by many reports, it is our opinion that simultaneous valve replacement and aortotomy bypass graft does not increase the risk of cardiac valve replacement substantially.

대동맥궁 절제술의 임상적 고찰

김경환,안혁,Kim, Kyung-Hwan,Ahn, Hyuk 대한흉부심장혈관외과학회 1994 Journal of Chest Surgery (J Chest Surg) Vol.27 No.11

From October 1990 to May 1993, 19 patients underwent replacement of the transverse aortic arch. [10 men, 9 women, mean age 52.5 years] Underlying diseases were acute aortic dissection [10 cases], chronic aortic dissection [4 cases],and aortic arch aneurysm [ 5 cases]. In 19 patients, 10 underwent partial replacement and 9 underwent total arch replacement. The cerebral protection was achieved by profound hypothermia [rectal temperature,16$^{\circ}$ to 2$0^{\circ}C$] associated with total circulatory arrest [mean 35.5 minutes]. In one patient, the aortic arch distal to the left common carotid artery was resected with the distal arch being cross-clamped and in another two patients, the selective cerebral perfusion was also applied during the period of total circulatory arrest via innominate artery and left common carotid artery because of longer total circulatory arrest time. Among 14 patients of aortic dissecton, 10 presented hypertension, 1 presented Marfan syndrome, 1 presented pregnancy-induced hypertension and 2 revealed no evidence of hypertension. All of the above 14 patients complained chest pain. Among 5 patients of aortic arch aneurysm, Be het disease was suspected in only one patient and atherosclerotic aneurysm was proved in another 4 patients. The overall hospital mortality was 32% [6/19]. In aortic dissection, the mortality was 43% [Acute aortic dissection 30%, chronic aortic dissection 75%] and in aortic arch aneurysm, the mortality was 0%. Follow-up was done in all survivors for from 7 months to 36 months[mean,17.3%].

의미론적인 단순화된 그림 및 표의문자를 인지하는 과정에 대한 fMRI 연구

김경환,이성기,송명성,권민정,정준영,박현욱,윤효운,Kim Kyung Hwan,Lee Sung Ki,Song Myung Sung,Kwon Min Jung,Chung Jun Young,Park Hyun Wook,Yoon Hyo Woon 대한자기공명의과학회 2003 Investigative Magnetic Resonance Imaging Vol.7 No.2

문자와 그림을 인식하는데 있어 인식패턴의 반구차이는 인지심리학적으로 널리 연구되어왔고 또 증명되어졌다. 일반적으로 그림을 인식하는 있어서는 우반구 우세를 문자를 인식하는 있어는 좌반구 우세를 이야기하는데 본 논문에서는 그 사실을 바탕으로 fMRI 연구를 진행하였다. 동양문화권에서 문자로 사용되고 있는 한자 역시 그림으로 인식한다는 견해가 있다는 것이다. 한자의 인지가 좌반구 또는 우반구 우세라는 엇갈린 견해들이 있다. 그래서 본 논문에서는 한자와 그림의 인식패턴에 대한 반구차이 및 활성화되는 두뇌의 영역을 규명하기 위해 비교 실험하였다. 자극으로 사용되어진 그림은 한자와 동일한 의미를 가진 단순화된 것이다. 실험 디자인은 일반적으로 사용되는 블록디자인을 사용하였고 SPM을 사용하여 분석하였다. 결론으로 한자와 그림 인식패턴 모두 반구우세성을 이야길 할 경우 시각영역인 후두엽 및 측두엽 부분에서는 우반구 우세가 보이지만 일반적으로 반구우세성을 이야기하기는 무리가 있는 것 같다. The different perceiving patterns of each picture, alphabetic words and Chinese characters, were widely investigated psychophysically. The more precise localisation can be done in terms of brain activity us-ing functional image technique such as PET and fMRI recently, Until now, there was no fMRI study to make direct comparison between perception of single Chinese character and simplified pictures (pictograph). We have made direct comparison of these two components using modern magnetic resonance techniques. We cannot confirm the right hemispheric dominance for perception of single Chinese character and pictographs. These two kinds of perceiving pattern can be underlying different mechanism.