Calabi-Yau Manifolds, Hermitian Yang-Mills Instantons, and Mirror Symmetry

Yang, Hyun Seok,Yun, Sangheon Hindawi Limited 2017 Advances in high energy physics Vol.2017 No.-

<P>We address the issue of why Calabi-Yau manifolds exist with a mirror pair. We observe that the irreducible spinor representation of the Lorentz group Spin(6) requires us to consider the vector spaces of two forms and four forms on an equal footing. The doubling of the two-form vector space due to the Hodge duality doubles the variety of six-dimensional spin manifolds. We explore how the doubling is related to the mirror symmetry of Calabi-Yau manifolds. Via the gauge theory formulation of six-dimensional Riemannian manifolds, we show that the curvature tensor of a Calabi-Yau manifold satisfies the Hermitian Yang-Mills equations on the Calabi-Yau manifold. Therefore, the mirror symmetry of Calabi-Yau manifolds can be recast as the mirror pair of Hermitian Yang-Mills instantons. We discuss the mirror symmetry from the gauge theory perspective.</P>

Profile^(Ⓡ), ProTaper™ 및 K^(3TM) Ni-Ti파일의 과기구 조작이 치근단공 변위에 미치는 영향

양현,양인석,황윤찬,황인남,윤숙자,김원재,오원만 대한치과보존학회 2007 Restorative Dentistry & Endodontics Vol.32 No.2

본 연구는 ProFile, ProTaper 및 K^(3)를 이용하여 과잉 기구 조작에 의해 근관 성형 시 근관의 만곡형태와 Ni-Ti 파일의 종류에 따라 치근단공이 어떻게 변위 되는지를 비교 분석하고자 시행되었다. 본 실험에서는 레진모형근관으로 J자와 S자의 근관 형태가 재현된 ENDO-TRAINING BLOC을 사용하였다. 근관 성형 기구로는 ProFile^(®), ProTaper™, K^(3TM)를 사용하였다. 총 60개의 레진모형근관을 사용하였으며, 사용된 레진모형근관 및 Ni-Ti 파일의 종류에 따라 10개씩 6개의 군으로 나누어 근관성형을 시행하였다. 근관 성형 전·후 이미지를 Image-analyzing microscope 100X를 이용하여 얻고 Photoshop 7.0 프로그램을 이용하여 중첩하였다. 이미지 분석 프로그램을 이용하여 근관 성형 전·후 치근단공의 중심으로부터의 직경 변화량과 면적을 측정한 결과 만곡된 근관의 성형시 치근단공이 주로 만곡의 외측으로 변위됨을 나타내며 ProFile이 ProTaper나 K^(3) 보다 통계적으로 유의성이 있게 작은 변화량을 나타내어 근관성형시 바람직한 기구임을 시사한다. This study was done to evaluate transportation of the apical foramen after 0.5 mm overinstrumentation by ProFile, ProTaper and K^(3) in simulated resin root canal. Sixty simulated resin root canal with a curvature of J and S-shape were divided into two groups. Each group consisted of three subgroups with 10 blocks according to the instruments used: ProFile^(®), ProTaper™, and K^(3TM). Simulated resin root canal was prepared by ProFile, ProTaper and K^(3) with 300 rpm by the crown-down preparation technique. Pre- and post-instrumentation apical foramen images were overlapped and recorded with Image-analyzing microscope 100X (Camcope, Sometech Inc, Korea). The amounts of difference in width and dimension on overlapped images were measured after reference points were determined by Image Analysis program (Image-Pro^(®) Express, Media Cybernetic, USA). Data were analyzed using Kruskal-Wallis and Mann-Whitney U-test. The results suggest that ProFile showed significantly less canal transportation and maintained original apical foramen shape better than K^(3) and ProTaper.

레진모형근관에서 엔진구동형 및 수동형 ProTaper 파일로 근관성형 후 근관형태 변화에 대한 비교연구

양인석,강인철,황윤찬,황인남,오원만 大韓齒科保存學會 2005 Restorative Dentistry & Endodontics Vol.30 No.5

본 연구는 형태 및 재질이 동일한 엔진구동형 ProTaper 파일과 수동형 ProTaper 파일을 이용하여 레진모형근관을 성형한 후 근관형태 변화를 비교 분석하고자 시행되었다. 본 연구에서는 레진모형근관으로 총 40개의 J자와 S자의 근관형태가 재현된 ENDO-TRAINING BLOC을 사용하였다. 근관 성형 기구로는 엔진구동형 Ni-Ti 파일로 ProTaper^(TM), 수동형 Ni-Ti 파일로 ProTaper^(®) For Hand Use를 사용하였다. 사용된 레진모형근관과 파일의 종류에 따라 10개씩 4개의 그룹으로 나누어 근관성형을 시행하였다. 근관 성형 전 · 후 이미지를 스캐너 (Color scanner, UMAX Techologies, Inc., USA)를 이용하여 얻은 후, Photoshop 7.0 프로그램 (Adobe System Inc., USA)을 이용하여 이미지를 중첩하였다. 이미지 분석 프로그램 (Image-Pro^(®) Plus, Media Cybernetic, USA)을 이용하여 치근단 쪽에서부터 0, 1, 2, 3, 4, 5, 6 및 7 ㎜ 수준에서 근관 성형에 따른 근관의 내측 및 외측 폭경의 변화량, 근관 총폭경의 변화량, 근관 중심축의 변위량을 측정하였다. 또한 근관 성형 시간을 기록하였다. 두 기구 사이의 유의성 검정을 위해 독립 표본 t-검정을 시행하여, 근관 성형 시 수동형 ProTaper 파일에 엔진구동형 ProTaper 파일에 비해 근관 중심축의 변위가 유의하게 덜 일어나며 근관의 원래 형태를 더욱 잘 유지할 수 있지만, 근관 성형시간은 길어질 수 있다는 결론을 얻었다. The purpose of this study was to compare the canal configuration after shaping by ProTaper rotary files and ProTaper hand files in resin simulated canals. Forty resin simulated canals with a curvature of J-shape and S-shape were divided into four groups by 10 blocks each. Simulated root canals in resin block were prepared by ProTaper rotary files and ProTaper hand files using a crown-down pressureless technique. All simulated canals were prepared up to size #25 file at end-point of preparation. Pre- and post-instrumentation images were recorded with color scanner. Assessment of canal shape was completed with an image analysis program. Measurements were made at 0, 1, 2, 3, 4, 5, 6 and 7 ㎜ from the apex. At each level, outer canal width, inner canal width, total canal width, and amount of transportation from original axis were recorded. Instrumentation time was recorded. The data were analyzed statistically using independent t-test. The result was that ProTaper hand files cause significantly less canal transportation from original axis of canal body and maintain original canal configuration better than ProTaper rotary files, however ProTaper hand files take more shaping time.

혈액투석요법 환자의 우울, 불안 및 수면장애에 대한 연구

윤석준,양창국,한홍무 大韓神經精神醫學會 1999 신경정신의학 Vol.38 No.5

연구목적 : 혈액투석요법을 받는 말기 신부전증 환자들은 불안이나 우울 등의 심인증상 외에도 여러 가지 수면장애를 호소할 수 있다. 말기 신부전증 환자에서 심인증상과 수면장애가 많을수록 삶의 질에 장애를 초래하며 혈액투석요법 도중 탈락이 높다. 저자는 본 연구에서 혈액투석요법 중인 환자의 우울, 불안 및 수면장애 등을 조사하여 향후 환자가료에 활용하고자 하였다. 방 법 : 부산시내 4곳의 혈액투석요법기관에서 혈액투석요법을 받는 말기 신부전증 환자 153명(남 87, 여 66)과 정신적, 신체적으로 건강한 동아대학교병원 행정직원 및 의과대학 학부모 113명(남 58, 여 55)을 대상으로 구조화된 면담과 자기평가척도를 실시하였다. 연구도구는 저자 등이 본 연구에 알맞게 개발한 인구통계학적 자료를 포함한 수면관련 설문지, 우울증 자가평가 척도인 Beck Depression Inventory(BDI), 불안 자가평가 척도인 State-Trait Anxiety Inventory(STAI)를 이용하였다. 결 과 : 환자군이 대조군에 비하여 신체증상 및 심인증상을 더 많이 호소하였고(p<0.05), 수면관련 불편을 더 많이 나타내었다(p<0.001). 환자군의 BDI 평균은 22.9로 대조군의 11.2보다 유의하게 높았다(p<0.001). BDI 점수를 기준으로 볼 때 남자환자 64명(74.7%), 여자환자 47명(71.2%)은 우울증군에 속하였다. STAI 평균 점수는 두 군간에 유의한 차이가 없었다. 환자군은 대조군에 비하여 입면잠복기와 수면 중 깨어 있는 시간이 더 길었고, 낮 동안의 졸리움 등 수면관련 불편을 더 많이 호소하고 있었다. 또한 환자군은 불면증(65.4%), 하지불편증후군(46.4%), 악몽(27.3%), 주기성사지운동장애(23.5%), 수면 식사장애(18.3%), 야경증(14.4%) 등을 유의하게 더 많이 호소하고 있었다(p<0.05). 결 론 : 혈액투석요법을 받고 있는 말기 신부전증 환자들은 대조군에 비해서 신체적, 심인적 증상을 유의하게 더 호소하고 불면증을 포함한 다양한 수면장애를 동반하고 있다. 또한 이들 사이에 높은 상호관계가 있는 바, 이는 혈액투석요법 증인 환자들에서 신체적 증상 및 심인적 증상뿐만 아니라 수면장애에 대한 치료적 접근이 필요함을 시사한다. Objectives : Psychological distresses and complaints in sleep, in addition to physical distresses such as pruritus and bone pain, are common in patients with hemodialysis. The purposes of this study were to investigate 1) the severity of physical distresses, 2) the severity of depression and anxiety, 3) the sleep disturbances, and 4) the correlation of the above variables in patients with hemodialysis. Methods : The patients with hemodialysis(male 87, female 66) and controls(male 58, female 55) completed a self-administered questionnaire package, which included Beck Depression Inventory, Spielberger's State-Trait Anxiety Inventory, and questions characterizing the reported sleep problems and quantitating the severity of the self-perceived physical and psychological conditions with linear visual analogue scales. Results : The results indicated that patients with hemodialysis complained of more physical distresses, more depressed mood, and more sleep disturbances suggesting insomnia, restless legs syndrome, periodic limb movement disorder, nightmare and obstructive sleep apnea syndrome, etc. There were significant positive correlations of physical distresses, depressed mood and sleep disturbances. However, there were no significant differences in state and trait anxiety between both groups. Conclusions : The authors suggest that the quality of life in patients with hemodialysis

潛堤의 反射 및 透過率에 關한 硏究

梁崙模,李文贊,金鍾石 釜山大學校 都市問題硏究所 1987 都市硏究報 Vol.1 No.-

The reflection and transmission effects by the change of space and size of the rectangular submerged breakwater installed in the constant depth of sea-bottom water were theoretically estimated and investigated by the potential connecting method and two dimentional hydraulic model test. In case of impermeable submerged breakwater, as it were, the effect of width, space and height of submerged breakwater were investigated sperately by the theoretical analyses and experiments on single and double submerged breakwaters. And, in the event of permeable submerged breakwater, space and height of submerged breakwater were investigated by experiments. According to this study, the following conclusions were obtained. 1) The theoretical and experimental values were very close in their numerical values in impermeable submerged breakwater. 2) The influences width and space of submerged breakwater on reflection and transmission effects were not constant but the repetition of increase and decrease and its influences became more greater as the height of submerged breakwater was more higher. On the contrary, there were little influences of width and height of breakwater on reflection and transmission effects in permeable submerged breakwater. 3) Double submerged breakwaters was more effective in wave damping effects than those of single submerged breakwater in impermeable submerged breakwater. 4) Wave damping effects of impermeable submerged breakwater were more greater than those of permeable submerged breakwater.

노즐형상비에 따른 디젤분무의 특성

양윤석,이창수,허종철 濟州大學校 産業技術硏究所 2001 산업기술연구소논문집 Vol.12 No.1

In this study. diesel spray characteristics has been conducted to investigate the effect on nozzle aspect ratio(L/D). A single hole nozzle which is 0.45mm in diameter and 2.78. 3.89. 5 in the nozzle aspect ratio is used. Injection pressure is 14MPa and ambient pressure are 0.1MPa and 3MPa. By nozzle aspect ratio. the disintegration process of a diesel spray was observed. The double flash method has been employed to visualize the developing process of the diesel spray.

하악 이부에 생긴 Angiolymphoid hyperplasia with eosinophilia(Kimura's disease)의 치험례

양윤석,조용석 大韓顎顔面成形再建外科學會 1996 Maxillofacial Plastic Reconstructive Surgery Vol.18 No.3

Angiolymphoid hyperplasia with eosinophilia(ALHE) is an uncommon, benign vascular proliferation with the background of a stroma which is heavily infiltrated by lymphocytes and eosinophils and includes lymphatic follicles with prominent germinal centers. ALHE primarily involves the skin and subcutis in head and neck as various forms of nodules. There has been considerable controversy about the relationship between ALHE and Kimura's disease. Kimura's disease, originally reported by Kimura et el., is an unusual granulation with proliferation of lymphoid tissue. Wells and Whimster published the first report describing a condition that resembled Kimura's disease and designated it as ALHE. For a time being two lesios are thought to be same lesion, but recently they are considered as two different entities, histopathologically. The cause of this disease remains unknown, and physicians have used a variety of treatment modalities including cryosurgery, steriod therapy, electrodesiccation, curettage, radiotherapy, laser therapy and surgical excision. But any treatment modality leaves problem of recurrence because the lesion is not well encapsulated. Being poorly encapsulated, the lesion's remnants are apt to be left and this markes some problems : recurrence and possible adjacent organ injury. In this case we misdiagnosed the lesion as well encapsulated benign mass. We performed excisional biopsy and experienced prolonged operation time and unwanted mentalis muscle injury. We think that the importance of poor encapsulation of ALHE should be stressed. So we report our experience with literature review.

J-R 곡선에 대한 시편크기의 영향에 관한 연구

조연제,석창성,김영진,양원호,최용식 成均館大學校 科學技術硏究所 1995 論文集 Vol.46 No.1

The objective of this paper is to investigate the constraint effect on fracture resistance curves. A series of fracture toughness tests with different specimen sizes taken from nuclear piping materials(SA312 TP347 SA516 Gr. 70) were performed. Test results show that fracture toughness is increased with increase in specimen size, probably due to the relaxation crack tip constraint. Elastic-plastic finite element analyses were also performed to investigate the constraint effect. Numerical results show that the stress triaxiality at the crack tip is the governing factor for fracture toughness.

한의진단명과 진단요건의 표준화 연구 III : 3차년도 연구결과 보고

최선미,양기상,최승훈,박경모,박종현,심범상,김성우,노석선,이인선,정진홍,이진용,김달래,임형호,김윤범,박성식,송태원,김종우,이승기,최윤정,신순식 한국한의학연구원 1997 한국한의학연구원논문집 Vol.3 No.1

The diagnostic requirements were suggested and explained regarding the systems of differentiation of symptoms and signs in the third year study of standardization and unification of the terms and conditions used for diagnosis in oriental medicine. The systems were as follows : - analyzing and differentiating of epidemic febrile disease - analyzing and differentiating in accordance with the Sasang constitution medicine based on four-type recognition - differentiation of disease according to pathological changes of Chong and Ren channels - standards for diagnosis of women's disease - standards for diagnosis of children's disease - standards for diagnosis of motor and sensor disturbance (-muscle. born, joint, etc.) - standards for diagnosis of neuropsychiatric disease - standards for diagnosis of five sense organ disease - standards for diagnosis of external disease The indivisual diagnosis pattern was arranged by the diagnostic requirements in the following order : another name, notion of diagnosis pattern, index of differentiation of symptoms and signs, the main point of diagnosis, analysis of diagnosis pattern, discrimination of diagnosis pattern, prognosis, a way of curing a disease, prescription, herbs in common use, disease appearing the diagnosis pattern, documents. The standards for diagnosis of each disease was arranged by the diagnostic requirements in the following order : another name, notion of disease, the main point of diagnosis, analyzing and differentiating of disease, analysis of disease, discrimination of disease, prognosis, a way of curing and prescription of disease, disease in western medicine appearing the disease in oriental medicine, documents.

노즐형상비에 따른 디젤분무의 특성

양윤석,이창수,허종철 제주대학교 산업기술연구소 2001 尖端技術硏究所論文集 Vol.12 No.1

In this study, diesel spray characteristics has been conducted to investigate the effect on nozzle aspect ratio(L/D). A single hole nozzle which is 0.45mm in diameter and 2.78. 3.89. 5 in the nozzle aspect ratio is used. Injection pressure is 14MPa and ambient pressure are 0.1MPa and 3MPa. By nozzle aspect ratio. the disintegration process of a diesel spray was observed. The double flash method has been employed to visualize the developing process of the diesel spray.