Wavelength Assignment Optimization in Uni-Directional WDM Ring

이희상,정지복,Lee, Hee-Sang,Chung, Ji-Bok 대한산업공학회 2000 산업공학 Vol.13 No.4

In this paper, we consider wavelength assignment problem (WAP) in Wavelength division multiplexed (WDM) unidirectional optical telecommunication ring networks. We show that, even though WAP on unidirectional ring belongs to NP-hard, WAP can be exactly solvable in real-sized WDM rings for near future demand. To accomplish this, we convert WAP to the vertex coloring problem of the related graph and choose a special integer programming formulation for the vertex coloring problem. We use a column generation technique in a branch-and-price framework for the suggested formulation. We also propose some generic heuristics and do the performance comparison with the suggested optimization algorithm.

정신분열증의 신경심리학적 소견

이희상,Lee, Hee-Sang 대한수면의학회 1995 수면·정신생리 Vol.2 No.2

Schiophrenia is characterized by a variety of cognitive dysfunctions. A number of research findings suggest that schizophrenic patients have global deficits in cognitive functions, such as attention, memory, executive functions, and motor functions. These cognitive deficits, once they arise, tend to become relatively stable. In spite of much efforts to search for the cognitive dysfunctions in schizophrenia, there are no specific deficits or localizations found. It is necessary that future neuropsychological research of schizophrenia should include relationships between symptoms and cognitive dysfunctions and their relationships to treatment.

치밀이음부 구조단백질인 Occludin에 대한 활성산소종의 영향

이희상,김대진,손동섭,정봉수,최형택,심규민,이금정,조혜진,김석중,이종찬,정윤희,김성수,이원복,Lee, Hee-Sang,Kim, Dae-Jin,Sohn, Dong-Suep,Jeong, Bong-Su,Choi, Hyung-Taek,Sim, Kyu-Min,Lee, Keum-Jeong,Cho, Hye-Jin,Kim, Suk-Joong,Lee, Jong-Chan,J 한국현미경학회 2004 Applied microscopy Vol.34 No.4

Cerebral microvessel endothelial cells that form blood-brain barrier (BBB) have tight junction for maintaining brain homeostasis. Occludin, one of tight junction protein, is crucial for BBB function. $H_2O_2$ induced occludin changes and effects in bovine brain BBB endothelial cells were examined in this study. The decrease of transendothelial electrical resistance (TEER) by $H_2O_2$ was due to disruption of occludin localization. Cytotoxicity test revealed that $H_2O_2$ did not cause cell death below 1 mM $H_2O_2$ within 4 hr. $H_2O_2$ caused intermittent disruption and loss of occludin at tight junctions and occludin disappeared with dose dependent manner from tight junction in confocal laser microscopy. But Western blot revealed that the total amounts of occludin increased by $H_2O_2$ administration. Transmission electron microscopy revealed that the ultrastructure of tight junction was not changed by $H_2O_2$. These data suggest that functional disruption of BBB by $H_2O_2$ was due to the localized loss of occludin in tight junction, but the expression of occludin increased in order to compensate the disrupted function in BBB. 뇌에서 혈액뇌장벽을 형성하는 내피세포는 치밀이음부를 통해 뇌의 항상성을 유지하고 있다. 치밀이음부의 단백질 중의 하나인 occludin은 뇌혈관장벽(BBB)의 기능을 유지하는 중요한 단백질로 인식되고 있다. 본 실험에서는 소의 뇌에서 배양된 BBB 내피세포에서 활성산소종의 하나인 $H_2O_2$에 의해 일어나는 occludin 단백질의 변화를 관찰하였다. $H_2O_2$에 의해 TEER가 감소하는 것은 occludin의 재분포에 의한 것이었다. 세포독성은 4시간내에서는 1mM $H_2O_2$ 이하에서는 나타나지 않았다. Confocal laser microscope으로 관찰한 결과, $H_2O_2$에 의해 occludin은 치밀이음부에서 중간중간이 사라져 감소해 있었고, 이러한 양상은 $H_2O_2$의 용량과 노출시간에 비례하였다. 그러나 Western blot 결과, occludin의 총량은 증가하였다. 투과전자현미경 관찰을 통해 $H_2O_2$가 세포사이의 결합의 구조에 뚜렷한 변화를 미치지 않는 것을 알 수 있었다. 이를 통해 $H_2O_2$에 의한 BBB 기능소실은 occludin이 치밀이음부에서 부분적으로 사라지는 것에 의하지만, 세포는 기능손상을 복구하기위한 방편으로 이 단백질의 생산을 더욱 증가시키는 것으로 생각된다.

정신과자문에 대한 타과 의사들의 태도

이희상,고경봉,Lee, Hee-Sang,Koh, Kyung-Bong 한국정신신체의학회 1994 정신신체의학 Vol.2 No.1

The authors investigated 131 nonpsychiatric physicians' attitudes toward psychiatric consultation, using questionnaires. A comparison was made as regards psychiatric consultation from nonpsychiatric physicians over position(staffs vs. residents) and department(medical vs. surgical). These findings are as follows ; 1) 51.9 percent of nonpsychiatric physicians estimated that less than 30 percent of their patientshadpgychiatricproblems. 2) The percentage of the patients referred for psychiatric consultation were 30 or less than 30 percent 3) Staffs tried to refer their patients to psychiatric department for psychiatric consultation more frequently than residents. 4) Medical physicians tried to refer their patients to psychiatric department for psychiatric consultation more frequently than surgeons. 5) Psychiatric consultation was estimated to be most frequently requested for overt psychiatric symptoms(23.0%) and past history of psychiatric treatment(20.8%). 6) The most frequent causes of not referring to department of psychiatry were found to be the patients' rejection(46.8%) and non-psychiatric physicians' dissatisfaction with the results of consultation (22.2%). 7) Medical physicians tended to explain the reasons for psychiatric consultation more adequately than surgeons. 8) Residents more specifically wrote the reasons for psychiatric consultation on the chart than staffs. The results suggest that staffs are more active in psychiatric consultation than residents, whereas medical physicians are more active than surgeons. Thus, education should be more emphasized for surgeons and residents, especially for the latter for effective consultation-liaison activity. On the other hand, psychiatrists should try to improve nonpsychiatric physicians' dissatisfactions with the results of psychiatric consultations, which will positively change their attitudes toward psychiatric consultation.

쥐의 뇌 미세혈관 내피세포를 이용한 뇌혈관장벽 내피세포의 배양과 특성

이희상,김석중,김대진,정윤희,김성수,이원복,김경용,Lee, Hee-Sang,Kim, Seok-Jung,Kim, Dae-Jin,Chung, Yoon-Hee,Kim, Sung-Su,Lee, Won-Bok,Kim, Kyung-Yong 한국현미경학회 2005 Applied microscopy Vol.35 No.4

쥐의 뇌로부터 미세혈관에서 분리하고 배양한 내피세포의 특성을 현미경관찰, 면역염색과 전기저항을 측정해 관찰하였다. 미세혈관 내피세포는 배양 후 $5{\sim}6$일 경에 단층을 형성하였으며 특징적으로 소용돌이치는 모양을 나타냈다. 내피세포 단층의 전기저항은 배양 후 5일 경까지 따라 증가하였고 이후로는 감소하였다. 면역형광염색에서 anti-GFAP, anti-GalC, anti-neurofilament 160/200 kD antibody에 대한 면역반응을 거의 찾아볼 수 없었어 별아교세포, 희소돌기아교세포 및 신경세포에 의한 우려할 만한 오염은 배제할 수 있었다. vWF 항원에 대한 면역반응은 내피세포의 세포질에 Weibel-Palade 과립이 전반적으로 퍼져 있었다. 치밀이음부를 구성하는 occludin, ZO-1, ZO-2에 대한 면역반응은 내피세포의 접촉부위에서 매우 특징적으로 나타나고 있었다. 요약하면 쥐의 뇌 미세혈관 내피세포를 분리, 배양하여 형태학적, 조직면역 화학적 방법과 전기저항을 측정하여 내피세포의 특성을 확인하였다. 이 생체외 혈액뇌장벽 모델은 앞으로 진행될 액뇌장벽의 특징을 규명하고자 하는 시험관내 실험에 유용하게 이용될 수 있을 것이다. The characteristics of primary cultured rat brain microvessel endothelial cells (RBMECs) were studied using microscopy, immunohistochemistry and measuring of transendothelial electrical resistance (TER). The RBMECs formed a monolayer by $5{\sim}6$ days after plating and showed characteristics of whirling appearance. The TER increased until day 5 and decreased then. There was few immunoreaction with anti-GFAP, anti-GalC, anti-neurofilament 160/200 kD antibodies. So the contamination of astrocyte, oligodendrocyte, and neuron. could be ruled out.. Immunoreaction to vWF antigen was widespread througout the cytoplasm as Weibel-Palade granule. Immunoreaction to tight junction proteins, i.e. occludin, ZO-1, and ZO-2 was seen at cell contact. In summary, RBMECs isolated and cultured showed morphological, immunohistochemical and electrical characteristics of blood-brain barrier (BBB). The in vitro BBB model can be used in studying characteristics of in vivo BBB.

“Early bird 학교스포츠클럽” 여가활동을 즐기는 학생의 생활에 관한 질적 연구

이희상 ( Lee Hee-sang ) 한국레저사이언스학회 2016 한국레저사이언스학회지 Vol.7 No.1

본 연구의 목적은 9시 등교제 시행으로 0교시에 G국제고등학교에서 이루어지고 있는 “Early bird 학교스포츠클럽” 여가활동에 참여하는 학생들의 경험 이야기를 듣고 경험의 의미를 심층적으로 탐색하는데 있다. 2015년 3월부터 11월까지 9개월간 “Early bird 학교스포츠클럽” 여가활동을 운영했던 연구자 자신의 경험을 자문화기술지로 기술하여 하나의 사례로서 제시하였다. 또한 자기회상, 자기성찰, 자기관찰, 참여관찰, 심층면담, 개방형 설문조사를 통해 자료를 수집하고 분석하였다. 연구 과정에서 질적 연구의 진실성을 확보하기 위해 장기적이면서 집중적인 관찰, 트라이앵귤레이션, 구성원 간 검토, 동료 간 협의를 실시하였다. 이러한 연구과정을 통해 나타난 결과는 다음과 같다. 첫째, “Early bird 학교스포츠클럽” 여가활동은 학생들의 진지한 여가활동으로서 다양한 체험의 기회를 제공하였다. 둘째, “Early bird 학교스포츠클럽” 여가활동은 학생들의 건강 체력을 증진하고 사회성과 공동체 의식 함양에 긍정적인 영향을 끼쳐 즐거운 학교생활로 이어졌다. The purpose of this study is to listen to the stories about students’ experience about participating in the School Sports Club, “Early bird School Sports Club” and to explore the meaning of the experience in depth. The Early bird School Sports Club has been conducted in G Global High School in the period zero as a result of 9 o’clock go to school system. This study, which was conducted for 9 months from March 2015 to November 2015, will propose the researcher’s own experiences as a single case by describing them in the form of an autoethnography. The researcher has managed the leisure activity, “Early bird School Sports Club.” For this study, the researcher collected and analyzed data undergoing a self-recall, a self-reflection, a self-observation, a participant observation, a in-depth interview and an open survey. In the process of research, a long-term and repetitive observation, triangulation, member check and peer debriefing were used in order to ensure the veracity of a qualitative research. The results of this study are as follows. First, the “Early bird School Sports Club" leisure activity provides students with a various opportunity of experience as a serious leisure activity. Second, “Early bird School Sports Club" leads students to a happy school life improving their physical health, influencing positively on relationships with friends and promoting their communal spirit.

케이블 텔레비전의 세계-지방 네트워크와 장소의 탈지방화

이희상 ( Hee Sang Lee ) 한국도시지리학회 2006 한국도시지리학회지 Vol.9 No.1

아웃도어 상품 광고에서 데페이즈망을 통한 육체, 사물, 장소의 재결합

이희상(Hee sang Lee) 한국문화역사지리학회 2016 문화 역사 지리 Vol.28 No.3

상품 광고는 다양한 지리적 배경과 담론을 수반하고 있다. 이와 같은 맥락에서 본 연구가 찾고자 하는 것은 아웃도어 상품 광고에서 육체, 사물, 장소가 결합하는 방식이다. 이를 위해 두 가지 공간적 개념이 이용된다. 하나는 미학적 개념인 ‘데페이즈망’이고, 다른 하나는 지리학적 개념인 ‘장소-부적합’이다. 본 연구는 자연이 아니라 도시를 공간적 배경으로 하는 아웃도어 상품 광고에 주목하면서, 그 광고 이미지가 시공간적 인접성에 바탕을 둔 사물(관념)의 연합을 깨트리는 미학적 기법인 데페이즈망에 해당한다는 것을 제시할 것이다. 본 연구는 그러한 광고 이미지가 육체, 사물(상품), 장소가 결합되는 방식을 변화시키면서, 장소-적합과 장소-부적합 사이의 경계를 어떻게 흩트리는지를 설명할 것이다. 그리고 본 연구는 그와 같은 광고 전략이 육체와 사물(상품)이 결합되는 공간적 범위를 자연에서 도시로 확대시켜서 아웃도어 상품 소비를 재창출하려는 공간 전략, 즉 일종의 ‘공간적 조정’이라는 점을 강조할 것이다. Advertisements for commodities involve various geographical backgrounds and discourses. In this context, what this research tries to look for is the way in which bodies, things and places in advertisements for outdoor commodities. For this, two spatial concepts are used: one is an aesthetic concept, ‘dépaysement’ and the other is a geographic concept, ‘out-of-place’. Focusing on advertisements for outdoor commodities of which spatial backgrounds are cities, not nature, the research suggests that such advertisement images are a kind of dépaysement as an aesthetic skill which breaks the association of things (ideas) based on contiguity in time and place. It explains how the advertisement images scatter the boundaries between in-place and out-of-place, changing the way in which bodies, things (commodities) and places are combined. And, it underlines that such an advertising strategy is a kind of ‘spatial fix’ as a spatial strategy to expand the spatial scope of the combination between bodies and things (commodities) from nature to cities and thus to recreate consumption of outdoor commodities.

수포성 피부병변을 보인 식도암이 동반된 피부근염

이희상 ( Hee Sang Lee ),최형욱 ( Hyung Uk Choi ),배주한 ( Ju Han Bae ),이숙경 ( Sook Kyung Lee ) 대한피부과학회 2002 대한피부과학회지 Vol.40 No.12

Dermatomyositis is a rare inflammatory myopathy` with characteristic skin manifestations and muscular weakness. Vesicle or bulla formation in the dermatomyositis is rare and probably related to the presence of an internal malignant process. We report a case of dermatomyositis associated with esophageal cancer in a 72-year old man who had vesicles and bullae on his arms. He had erythema and edema on the face, chest, abdomen, back and legs for 20 days. Tense vesicles and bullae were found on his forearms and hands. Diagnosis of dermatomyositis was established by clinical manifestations, muscle enzyme study, electromyogram and histopathological findings of the skin. Adenocarcinoma of esophagus was found by gastroendoscopy. He was treated with total esophagectomy and topical steroid, but died of pneumonia and septicemia. (Korean J Dermatol : 2002;40(12) : 1538∼1542)

On The Quadratic Cost Partition Problem

이희상 ( Hee Sang Lee ),( George Nemhauser ) 대한산업공학회 1992 대한산업공학회 추계학술대회논문집 Vol.1992 No.-