전통 단청안료 표면의 물리적 특성 변화 모니터링

김지선,정혜영,변두진,유민재,김명남,이선명,Kim, Ji Sun,Jeong, Hye Young,Byun, Doo-Jin,Yoo, Min Jae,Kim, Myoung Nam,Lee, Sun Myung 한국문화재보존과학회 2020 보존과학회지 Vol.36 No.6

석간주, 진사, 황토, 자황, 웅황, 석록, 뇌록, 석청 및 백토 등 천연 무기안료 9종의 성능과 수명을 평가하고자 실내 촉진내후성과 옥외폭로 시험을 수행하였다. 실내 촉진내후성 시험법은 국내 기후 특성 및 단청의 위치 환경을 반영하여 설계하였고 필드 재현성을 확인하기 위해 서울 숭례문과 대전 연구소 등 2개소에서 옥외폭로 시험을 병행하였다. 또한 누적 자외선량을 기준으로 안료 표면의 물리적 특성 변화를 모니터링하였다. 이 결과, 석간주와 백토는 초기에 미세균열이 발생하지만 안정화된 반면 진사와 석록은 균열이 지속적으로 확대되었다. 황토와 뇌록은 수분 및 송진에 의한 얼룩이 두드러졌고 자황, 웅황 및 석청은 입자의 광택 저하가 나타났다. 각 시험별 안료의 색 변화는 절대적인 수치 차이가 있을 뿐 색도 변화 양상은 유사하였다. 백토와 뇌록의 색차(𝚫E) 값이 5 이하로 가장 작고 진사는 28 이상으로 컸다. 안료 표면의 물리적 변화는 실내 촉진내후성 시험보다는 옥외폭로 시험이, 옥외폭로 시험에서는 대전 연구소보다 서울 숭례문에서 가중되었다. 이는 옥외폭로 시험이 큰 폭의 온·습도 변화, 분진 침적에 따른 오염 등 다양한 환경에 노출되고, 특히 서울 숭례문은 총 누적 자외선량(334 MJ/m²)에 도달하는 데까지 오랜 시간이 소요되어 노출 기간이 장기화되었기 때문이다. This study aimed to assess the performance and life of nine natural mineral dancheong pigments: Seokganju, Jinsa, Hwangto, Jahwang, Wunghwang, Seokrok, Noerok, Seokcheong, and Baekto. The design of the accelerated weathering test considered the domestic climate characteristics and the location of Dancheong. Outdoor weathering tests were conducted at the Research Institute in Daejeon and the Sungnyemun Gate in Seoul to confirm the field reproducibility of the accelerated weathering test. Monitoring of the physical changes in pigments through accelerated and outdoor weathering tests are based on ultraviolet exposure dose. Despite small cracks at the beginning of the tests, the monitoring showed that Seokganju and Baekto had no marked physical changes, but the surface cracks of Jinsa and Seorok continue to expand. Hwangto and Noerok were marked with water or were resin stained, and the particles of Jahwang, Wunghwang, and Seokcheong had lost their luster. Despite the absolute difference in color change in each test, the final chromaticity change patterns of pigments were similar in that the color difference between Baekto and Noerok was below five, and Jina was above 28. The physical and surface color pigment changes were more concentrated in outdoor weathering tests than in accelerated tests, and the Seoul site was more intense than the Daejeon site. This is because outdoor weathering tests are exposed to severe variations of temperature and moisture or deposition of dust particles and, in the case of Seoul, the site is more exposed to the external environment than the Daejeon site.

Acid Texturing에 의한 태양전지용 다결정 실리콘 기판의 표면 반사율 감소

김지선,김범호,이수홍,Kim, Ji-Sun,Kim, Bum-Ho,Lee, Soo-Hong 한국전기전자재료학회 2008 전기전자재료학회논문지 Vol.21 No.2

To improve efficiency of solar cells, it is important to make a light trapping structure to reduce surface reflectance for increasing absorption of sun light within the solar cells. One of the promising methods that can reduce surface reflectance is isotropic texturing with acid solution based on hydrofluoric acid(HF), nitric acid($HNO_3$), and organic additives. Anisotropic texturing with alkali solution is not suitable for multicrystalline silicon wafers because of its different grain orientation. Isotropic texturing with acid solution can uniformly etch multicrystalline silicon wafers unrelated with grain orientation, so we can get low surface reflectance. In this paper, the acid texturing solution is made up of only HF and $HNO_3$ for easy controlling the concentration and low cost compared to acid solution with organic additives. $HNO_3$ concentration and dipping time were varied to find the condition of minimum surface reflectance. Textured surfaces were observed Scanning Electron Microscope(SEM) and surface reflectance were measured. The best result of arithmetic mean(wavelength from 400 nm to 1000 nm) reflectance with acid texturing is 4.64 % less than alkali texturing.

Influence of internal connection length on screw loosening in internal connection implants

김지선,박영범,최현민,김성태,김현철,김선재,문홍석,이재훈,Kim, Ji-Sun,Park, Young-Bum,Choi, Hynmin,Kim, Sungtae,Kim, Hyeon Cheol,Kim, Sun Jai,Moon, Hong-Seok,Lee, Jae-Hoon The Korean Academy of Prosthodonitics 2017 대한치과보철학회지 Vol.55 No.3

목적:본 연구에서는 long internal connection 형태의 임플란트 지대주를 내부 연결 길이에 변화를 주어 임플란트-지대주 결합부의 안정성을 비교 평가해 보고자 하였다. 재료 및 방법: Long internal connection의 임플란트(Replus system, $4.7{\times}11.5mm$)를 각각 지대주의 길이에 따라 4개의 군(1, 2, 3, 4 mm 군)으로 나누었고 총 20개의 시편을 사용하였다. 시편을 레진에 매몰하여 고정시키고 100 N의 힘으로 임플란트 장축에 대해 30도의 각도에서 $1.0{\times}10^6$ 번의 반복하중을 가한 후 하중 전 후의 풀림회전력의 차이를 계산하여 95% 유의수준에서 Kruskal-Wallis 검정 방법을 통해 통계 분석하였다. 결과:지대주 내부 길이에 따른 풀림 회전력의 통계적 유의성은 나타나지 않았으며 (P > .05) 어떤 시편에서도 완전한 나사 풀림이나 나사 파절은 관찰되지 않았다. 결론: 내측 연결 임플란트에서 지대주 내부길이에 따른 나사 풀림의 정도는 차이가 나지 않았다. Purpose: The purpose of this study was to evaluate whether the internal abutment length affected screw stability in an internal connection implant. Materials and methods: Twenty long internal connection implants (Replus system, $4.7{\times}11.5mm$) were selected for this investigation. Abutments were assigned to four groups depending on the length of the internal connection (abutments with internal lengths of 1, 2, 3, and 4 mm, respectively). Each implant fixture specimen was embedded in resin medium and connected to an abutment with an abutment screw. A load of 100 N, applied at an angle of $30^{\circ}$ to the long axis of the implant, was repeated for $1.0{\times}10^6$ cycles. Reverse torque values (RTV) were recorded before and after loading, and the change in RTV was calculated. Data were analyzed with the Kruskal-Wallis test. Results: The change in RTV was not significantly different among the groups (P>.05). Screw loosening and fractures were not observed in any groups, and joint stability was maintained. Conclusion: The internal length of the abutment may not significantly affect the degree of screw loosening.

김춘수 시의 환유적 읽기

김지선 ( Ji Sun Kim ) 한국언어문화학회 2001 한국언어문화 Vol.19 No.-

This characterizes the Kim chun-su`s poem Duˇl-rim, Dostoevski(1997) and chair and stairs(1999)-through metonymic reading. The 1990`s is the period that postmodern symptoms conspicurously appear in arts and culture. His poems have both contemporary universality, which is postmodern and the experimetal mind that the very method of composing a poem show a thought. The postmodrn symptoms in his poems is shown off in deconstructing aspect. The deconstruction in a formal aspect-deconstructing a discription system and a completed narration-indicates the recognition that the universe is indeterminable, incidental and relative. If metaphor and metonymy are extended as one of the ways recognizing this universe, his poems show the metonymic recognition. D??l-rim. Dostoevski has intertxstuality with Dostoevski`s novels and poems prior to Kim. Kim`s poems have a unique description system which delays meanings. It removes `Signified` and `Signified` turns another `Signifer`. This description system reflects the aspects that the meanig is open, not finished. In chair and stairs, the historical and ordinary narration has no totality. A metonynic image intrudes, breaking and transferring a poetic meanig and acts as fragmenting the narration. Tihs means a denial of history.

상악동 골이식술을 동반한 임플란트 식립 시 골이식재의 높이 변화에 대한 방사선학적 평가

김지선,이서경,채경준,정의원,김창성,최성호,조규성,채중규,김종관,방은경,Kim, Ji-Sun,Lee, Seo-Kyoung,Chae, Gyung-Joon,Jung, Ui-Won,Kim, Chang-Sung,Choi, Seong-Ho,Cho, Kyoo-Sung,Chai, Jung-Kyu,Kim, Chong-Kwan,Pang, Eun-Kyoung 대한치주과학회 2007 Journal of Periodontal & Implant Science Vol.37 No.2

The edentulous posterior maxilla generally provides a limited amount of bone height because of atrophy of the ridge and pneumatization of the maxillary sinus, Maxillary sinus augmentation is one of the surgical techniques for reconstruction of the severely resorbed posterior maxilla. The purpose of this study was to evaluate the survival rate of implants and the long-term changes of graft height after maxillary sinus augmentation by lateral window approach. From September 1996 to July 2004, maxillary sinus augmentation with mixed grafts of autograft, allograft, xenograft and alloplast were performed on 45 patients and 100 implants were placed. We evaluated the survival rate of implants and the changes of BL(bone length)/IL(implant length) according to time using panoramic radiographs. The survival rate of implants was 91.0% for follow-up period. The mean reduction of graft heights was 0.34mm(3.0%) for 6 months and 1.22mm(1O.66%) for 3 years after augmentation. The total mean BL/IL was $1.34{\pm}0.21$ during 5 year observation period after augmentation and decreased slightly over time. The result means that graft materials were stable above the implant apex. BL/ILs of 1stage procedure were significantly decreased at 1-2 year, 3-4 year after augmentation and no statistically significant changes were observed in those of 2 stage procedure. The graft materials of both procedures were stable above the implant apex. No statistically significant changes of BL/IL were observed in the grafts combined with low amount of autogenous bone or without autogenous bone. The graft materials of both groups were stable above the implant apex. The results indicated that the placement of dental implants with maxillary sinus augmentation showed predictable clinical results and the grafts combined with low amount of autogenous bone or without autogenous bone had long-term resistance to resorption in maxillary sinus.

DEA-Tier를 이용한 국내 지식기반 건축서비스업의 혁신 성과 개선에 관한 연구 - 건축설계사무소를 중심으로 -

김지선,이훈구,이윤선,김재준,Kim, Ji-Sun,Lee, Hoon-Ku,Lee, Yoon-Sun,Kim, Jae-Jun 한국건설관리학회 2013 한국건설관리학회 논문집 Vol.14 No.2

지식서비스 산업은 지식의 생산, 가공, 활용을 통하여 부가가치를 창출하는 산업을 말한다. 지식 서비스 산업은 다른 서비스 산업에 비해 혁신 지향적이고 타 분야에 미치는 영향이 큰 특성을 지니지만, 이에 대한 연구는 미미한 실정이다. 본 연구에서는 지식 서비스를 창출하는 설계사무소의 기술 혁신의 필요성을 제기하며 건축설계사무소의 혁신 성과를 효율성 측면에서 분석하였다. DEA-Tier분석을 이용하여 건축설계사무소의 효율성의 크기에 따라 분류하고, 효율성 격차가 현저한 건축설계사무소들에게는 단기적, 중기적, 장기적인 관점에서의 실질적인 벤치마킹 경로까지 제시하여 향후 설계서비스업의 효율성 제고 전략 수립에 필요한 방법론을 제시하였다. Knowledge-based Service Industry is an industry that creates added value through the production, processing, and use of knowledge. Comparing to other service industries, it is innovation-oriented business endeavors having the characteristics that exert the great influences on other fields. Meanwhile, however, research efforts thereof are yet insignificant. In this study, we analyzed the innovation performance of architectural design office which creates knowledge services, having raised the necessity of innovation of the design office. The innovation performance were classified according to the extent of efficiency of the architectural design office making use of DEA-Tier analysis, and, for those architectural design offices that showed significant differences in efficiency, we presented the case studies of the firms that were substantial benchmarking targets from short, medium, and long-term perspectives.

GMA 용접공정을 이용한 오픈갭 수평고정관 초층 용접의 실험적 연구

김지선,김일수,박창언,나현호,이지혜,정성명,Kim, Ji-Sun,Kim, Ill-Soo,Park, Chang-Eun,Na, Hyun-Ho,Lee, Ji-Hye,Jung, Seong-Myeong 대한용접접합학회 2011 대한용접·접합학회지 Vol.29 No.3

Since welding process for most pipelines with large diameter has been carried out by the manual process, automation of the welding process is necessary for the sake of consistent weld quality and improvement in productivity. Therefore the development of the optimized algorithm to decide the welding condition is an effective technique to prove the feasibility of interface standards and intelligent control technology to increase productivity and reduce the cost of system integration. In this study, the pipe welding experiment has been carried out using plused GMA welding process to select optimal welding condition. And necessary information in root-pass welding has been obtained by applying in the pipeline using the selected welding conditions through the welding experiment.

GMA 위보기 및 수직자세 초층용접 최적조건 선정에 관한 실험적 연구

김지선,김인주,김일수,Kim, Ji-Sun,Kim, In-Ju,Kim, Ill-Soo 대한용접접합학회 2012 대한용접·접합학회지 Vol.30 No.6

Due to increase in demand of stable and long pipelines in natural gas industry, wide range of researches are being performed on automation welding to improved welding quality with respect to weld process parameters in real time measurement. In particular, the coupling between the pipe manufacturing process and location of the weld seam, the measured size of the gap that exists in the weld position and the weld angle depending on whether the movement of molten weld. This is due to absence of controlling welding penetration position, depending on the required size of the angle of the setting. In addition, the optimum welding conditions must be considered while selecting, the correlation between these variables and the systematic correlation has not yet been identified. Therefore, in most welded pipe root-pass weld solely depends on the experience of workers in relation to secure a stable weld quality. In this study, automation welding system is implemented to select a suitable root-pass STT (Surface Tension Transfer) welding method using the optimal welding conditions. To successfully accomplish this objective, there were various welding conditions used for welding experiment to confirm that the assessment required for construction through the pipe and automatic welding process is proposed to optimize this plan.

누낭조영술에 의한 눈물길 폐쇄의 분류와 임상적 고찰

김지선,안민,Ji sun Kim,Min Ahn 대한안과학회 2005 대한안과학회지 Vol.46 No.2

Purpose: To analyze the outcome and therapeutic effectiveness of dacryocystography in patients with epiphora. Methods: A retrospective study was carried out on 270 patients (385 eyes) who had undergone dacryocystography for epiphora from 1998 to 2002. The factors assessed were age, sex, duration of epiphora, incidence rate of obstruction site of lacrimal system, reliability of dacryocystography as a diagnostic method, correlation of syringing with dacryocystography, correlation of probing with dacryocystography. Results: The incidence rate of lacrimal system obstruction on dacryocystography was 74% (285 eyes). The most common site was nasolacrimal duct (138 eyes, 48.4%), followed by sac (78 eyes, 27.4%), common canaliculus (51 eyes, 17.9%), and superior and inferior canaliculus (18 eyes, 6.3%). Dacryocystography showed 74% sensitivity and 87% specificity (p<0.01). The results of syringing and probing correlates poorly with the results of dacryocystography. Conclusions: Dacryocystography is a useful method to assess the lacrimal passage system, and the obstruction site so that therapy can be accurately planned, particularly in patients with epiphora.

자살 시도와 자살 사고 간 반응억제 사건유발전위 비교 연구

김지선,권영준,심세훈,Kim, Ji Sun,Kwon, Young Joon,Shim, Se-hoon 대한불안의학회 2020 대한불안의학회지 Vol.16 No.1

Objective : There have been limited scientific studies differentiating those who attempt suicide from those who think about suicide but do not attempt suicide. Altered event-related potential (ERP) performance, such as GoNogo ERP has been regarded as the neurocognitive processes associated with behavioral inhibition and poor impulse control. The purpose of this study was to investigate the association between Nogo ERP and suicide attempt. Methods : A total of 63 participants (33 participants with suicide ideation and 30 with suicide attempt) were recruited, and performed GoNogo tasks during the electroencephalogram measurement. Depression, anxiety, emotional regulation and impulsivity were evaluated by self-rating scales. The clinical measures and Nogo P3 component were compared between the groups. The correlational analyse was conducted to evaluate the relationship between the clinical characteristics and the Nogo P3 component. Results : Participants with suicide attempt significantly decreased the Nogo P3 amplitudes at the frontal-central electrode than participants with suicide ideation (p=0.004, FDR adjusted p=0.032). In the correlation analysis, the Nogo P3 amplitude at frontal-central electrode was correlated with the total score of the Barrett impulsivity scale (r=-0.383, p=0.002), attentional impulsivity (r=-0.365, p=0.003) and motor impulsivity (r=-0.389, p=0.002) subscales of the Barrett impulsivity scale. Conclusion : These findings suggest that the decreased Nogo P3 amplitude may be one of the candidates of biological marker for poor impulse control in those who attempt suicide.