문화재 비파괴 진단과 디지털화

송정일 ( Jung Il Song ),김한슬 ( Han Seul Kim ) 공주대학교 문화재보존과학연구소 2019 문화재과학기술 Vol.14 No.1

방사선 기술은 우리 일상생활에 다양하게 활용되고 있다. 이미 유럽 등의 국가에서는 문화재 비파괴 진단, 문화재 보존복원 분야에서 보편화되어 연구 및 조사에 활용되고 있다. 방사선의 물질 투과 특성을 이용한 문화재 비파괴 진단은 유물 내부 결함, 제작 기법, 구조 형태를 조사하는 문화재 보존처리 과학적 기록화 과정이다. 문화재 방사선 비파괴 진단은 필름(Film)에서 방사선 투과 결과를 확인하는 아날로그 방식이었으나, 최근에 X선 CR (Computed Radiography)과 X선 CT (Computed Tomography)의 디지털 데이터 방식이 활용되고 있다. 이러한 디지털 방식의 데이터는 디지털 문화유산(Digital Heritage)의 원천 디지털 자원이 될 수 있다. Radiation technology is used in various ways in our daily life. In European countries, radiation is used for non-destructive diagnosis, conservation and restoration of cultural heritage. Non-destructive diagnosis of cultural heritage using the material penetration properties of radiation is a process of examining production techniques and structural forms. Nondestructive diagnosis of radiation was an analog method for confirming the results of radiation transmission in films, but recently, digital data methods of X-ray Computed Radiography (CR) and X-ray Computed Tomography (CT) have been used. Digital data can be a source of digital resources for your digital heritage.

Computed Radiograhpy (CR)를 통한 목재 수종별 X선 투과 이미지 해석을 위한 기초연구 (1)

송정일,김한슬,Song, Jung Il,Kim, Han Seul 한국문화재보존과학회 2021 보존과학회지 Vol.37 No.3

The use of digital copies of film-based analog images and the introduction of digital radiographic imaging systems using image plates gradually replace the non-destructive radiationirradiation method of Cultural Heritage. The quality of images obtained from this technique is affected by conditions such as tube voltage, tube current, and exposure time, type of image acquisition medium, distance of the artifacts from the image acquisition medium, and thickness of artifacts. In this study, we evaluated the grayscale image obtained using GE's Computed Radiograhpy (CR) imaging system, the transmission characteristics of the X-ray source for each tree type (pine, chestnut, sawtooth oak, ginkgo) used in wooden Cultural Heritage, and the signal-to-noise ratio (SNR) and contrast. The GE's CR imaging were analyzed using the Duplex wire image quality indicator, line-pair gauges. 문화재 방사선 비파괴 투과 조사 방식은 이미지플레이트(Image Plate, IP)를 사용하는 디지털 방사선영상시스템(Computed Radiography, CR)이 도입되면서 필름방식의 아날로그 이미지에서 점차 디지털 이미지로 교체되고 있다. 방사선 비파괴 투과 조사의 이미지 품질은 촬영 조건(관전압, 관전류, 노출시간), 영상 획득 매체, 촬영 거리, 유물의 두께 등이 영향을 미친다. 이 논문에서는 목재 문화재에 주로 사용되는 수종(소나무, 밤나무, 은행나무, 상수리나무)에 X선 선원의 투과 특성을 GE사(社)의 CR 영상 시스템을 통해 획득된 이미지의 그레이 스케일(Gray Scale)을 분석한 후 신호 대 잡음비(signal to noise ratio) 및 대조도를 평가하고, 이중-선 상질계(Duplex-wire image quality indicator), 구형파 차트(line-pair gauges), 선형 식별계(Image Quality Indicator)를 이용하여 이미지를 분석하였다.

텔레매틱스 환경에서 유무선 통합 서비스를 위한 서비스 플랫폼 구조 연구

정도성(Jung, Do-Sung),송정은(Song, Jung-Eun),김병국(Kim, Byung-Gook),정재일(Jung, Jae-Il) 한국통신학회 2005 한국통신학회 학술대회논문집 Vol.2005 No.6

고려 나전국화넝쿨무늬합의 제작기법 연구

박수진,송정일,김한슬,조아현,박종서,Park, Su Zin,Song, Jung Il,Kim, Han Seul,Jo, Ah Hyeon,Park, JongSeo 한국문화재보존과학회 2020 보존과학회지 Vol.36 No.6

X-선을 이용한 비파괴 조사와, 현미경 조사를 통해 고려 나전국화넝쿨무늬합(고려나전합)의 구조와 제작기법을 확인하고, 보존상태를 파악하였다. 조사결과, 고려 나전국화넝쿨무늬합은 침엽수재를 바탕재료로 사용하였으며, 목재 위에는 직물을 바른 뒤에 옻칠을 한 것으로 확인되었다. 합의 구조는 판재를 반화형으로 가공한 뒤에 측면에 목재를 덧붙여서 제작하였고, 측벽으로 사용한 부재는 일정한 간격으로 칼집을 내어서 곡선형으로 가공하기 용이하게 만든 것으로 확인되었다. 나전의 가공은 주름질을 사용하였으며, 대모장식에는 복채기법이 사용되었다. 금속선은 단선과 착선이 사용되었다. In this paper, we present a nondestructive analysis using X-ray and microscopic investigation to detect the structure, manufacturing technique and preservation status of the Goryeo lacquered box Inlaid with Mother-of-pearl Chrysanthemum and Scroll Design (Goryeo Lacquered Box). We confirm that the Goryeo Lacquered Box consists of the soft wood as the basic material. The soft wood was coated with textile and then lacquered. The box structure of the Goryeo Lacquered Box was formed of wooden boards with wood plants added to the side, after processing into a trefoil-shaped. The wooden sides of the Goryeo Lacquered Box were cut at regular intervals for easier processing into a curved shape. Moter-of-pearl, tortoiseshell, and metal wire were used to decorate the surface. mother-of pearl was the cutting processing, and tortoiseshell was used for back coloring. The metal line was constructed using one line and twist line.

화력발전보일러의 연소가스편류가 튜브의 건전성에 미치는 영향

정재진(Jung Jae-Jin),송정일(Song Jung-Il) 대한기계학회 2009 대한기계학회 춘추학술대회 Vol.2009 No.5

Flue gas flow deviation in upper furnace and convection tube bank is an important but a less reported issue in large-scale opposed wall fired boilers, since it related to the boiler control and reliability. Field test is conducted in this paper to study the relationship between flue gas flow deviation and tube reliability. Several items of field test, including flue gas temperature, NOx, CO and O₂, are monitored at boiler upper horizontal flue gas flow pass, upper convective rear pass and economizer exit by using a spatially distributed sensor and probe. The analysis results show that the flue gas flow deviation is directly affect to the tube erosion life and poor combustion conditions as a result of poorly controlled local fuel/air distribution within the boiler furnace are highly related to the flue gas flow deviation.

보일러 내부 고온가스에 노출된 전열 튜브에서의 열유속 평가 방법

정재진(Jung Jae-Jin),송정일(Song Jung-Il) 한국태양에너지학회 2009 한국태양에너지학회 학술대회논문집 Vol.2009 No.11월

Most of the fossil power plants firing lower grade coals are challenged with maintaining good combustion conditions while maximizing generation and minimizing emissions. In many cases significant derate, availability losses and increase in unburned carbon levels can be attributed to poor combustion conditions as a result of poorly controlled local fuel and air distribution within the boiler furnace. The poor combustion conditions are directly related to the gas flow deviation in upper furnace and convection tube-bank but a less reported issue related to in large-scale opposed wail fired boilers. In order to develop a on-line combustion monitoring system and suggest an alternative heat flux estimation method at tube bank, which is very useful information for boiler design tool and soot blower optimizing system, field test was conducted at operating power boiler. During the field test the exhaust gases' temperature and tube metal temperature were monitored by using a spatially distributed sensors grid which located in the boiler's high temperature vestibule region. At these locations, the flue gas flow is still significantly stratified, and air in-leakage is minimal which enables tracing of poor combustion zones to specific burners and over-fire air ports. Test results showed that the flue gas monitoring method is more proper than metal temperature distribution monitoring for real time combustion monitoring because tube metal temp. distribution monitoring method is related to so many variables such as flue gas, internal flow unbalance, spray etc.. Heat flux estimation at tube bank with flue gas temp. and metal temp. data can be alternative method when tube drilling type sensor can't able to use.

발전용 보일러의 최적연소조정기법에 대한 실험적 연구

정재진(Jung Jae-Jin),송정일(Song jung-Il) 한국태양에너지학회 2009 한국태양에너지학회 논문집 Vol.29 No.5

J-적분을 이용한 후판 부분용입 다층용접재의 파괴 해석

김석,송정일,Kim, Seok,Song, Jung-Il 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.2

Partial penetration welding joint is defined as groove welds welded from one side, without steel backing or groove welds welded from both sides but without back gouging. So it has an unwelded portion at the root of the weld. Study of partial penetration weldment fracture behavior includes residual stress analysis and fracture analysis. The J-integral loses its path independency in residual stress field. Therefore, it is necessary to introduce a new J-integral, J, which is defined including the effect of plastic deformation and thermal strain. In this study, theoretical formulation and program were developed for the evaluation of J-integral for the crack tip located in the weldment. Evaluations of fracture behavior were performed for partial penetration multi-pass weldment of 25.4mm thick plate by J-integral. From a point of fracture in partial penetration multi-pass welding, it seemed to be better to control root face smaller than 6.35mm.

발전보일러의 최적연소조정에 대한 실험적 연구

정재진(Jung Jae-Jin),송정일(Song Jung-Il) 한국태양에너지학회 2009 한국태양에너지학회 학술대회논문집 Vol.- No.-

Fossil power plants firing lower grade coals or equipped with modified system for NOx controls are challenged with maintaining good combustion conditions while maximizing generation and minimizing emissions. In many cases significant derate, availability losses and increase in unburned carbon levels can be attributed to poor combustion conditions as a result of poorly controlled local fuel and air distribution within the boiler furnace. In order to develop a on-line combustion tuning system, field test was conducted at operating power boiler. During the field test the exhaust gases’ O₂, NOx and CO was monitored by using a spatially distributed monitoring grid located in the boiler’s high temperature vestibule and upper convective back-pass region. At these locations, the flue gas flow is still significantly stratified, and air in-leakage is minimal which enables tracing of poor combustion zones to specific burners and over-fire air ports. using these monitored information we can improving combustion at every point within the furnace, therefore the boiler can operate at reduced excess O₂ and gas temperature deviation, reduced furnace exit gas temperature levels while also reducing localized hot spots, corrosive gas conditions, slag or clinker formation and UBC. Benefits include improving efficiency, reducing NOx emissions, increasing output and maximizing availability. Discussion concerning the reduction of greenhouse gases is prevalent in the world. When taking a practical approach to addressing this problem, the best way and short-term solution to reduce greenhouse gases on coal-fired power plants is to improve efficiency. From this point of view the real time optimized combustion tuning approach is the most effective and implemented with minimal cost.

투석 치료중인 만성 신부전 소아에서의 지질 및 지질단백 이상

김정수,송정한,박혜원,정해일,김진규,최용,고광욱,Kim Jung-Sue,Song Jung-Han,Park Hye-Won,Cheong Hae-Il,Kim Jin-Q,Choi Yong,Ko Kwang-Wook 대한소아신장학회 1997 Childhood kidney diseases Vol.1 No.2

목적 : 말기 신부전 환자에서 심혈관계 질환은 유병율 및 사망율의 중요한 원인중 하나이다. 이들 환자에서 흔히 동반되는 고지질단백 혈증은 심혈관계 질환의 위험인자로 작용하며, 특히 lipoprotein(a)[Lp(a)]는 관상동맥 질환과 혈전증의 위험 인자로 알려져 있다. 소아에서도 만성 신부전시 고지질 혈증이 보고되어 있다. 저자들은 투석 치료중인 만성 신부전 소아를 대상으로 혈중 지질, 지질단백 및 Lp(a)의 농도 변화를 분석하였다. 방법 : 서울대학교 어린이병원 소아과에서 유지 혈액 투석을 받고 있는 환아 10명과 지속성 외래 복막 투석을 받고 있는 환아 14명을 대상으로 정맥 혈청중 지질, 지질단백 및 Lp(a)농도를 측정하여 건강 대조군과 비교하였으며, Lp(a)의 혈중 농도에 따른 다른 지질단백의 혈중 농도를 비교하였다. 혈액투석(hemodialysis, HD)환아군의 평균 연령이 $162{\pm}59$ 개월, 남녀비는 7:3 이었으며 복막투석(peritoneal dialysis, PD)환아군의 평균 연령은 $123{\pm}69$개월, 남녀비는 6:8 이었다. 결과 : 1) 연령, 성별, 비만지수, 투석기간은 HD군과 PD군 간의 차이가 없었으나 혈중 단백과 알부민치는 PD군에서 유의하게 낮았다. 2) HD군과 PD군 모두에서 혈중 콜레스테롤, 중성지방, 저비중 지질단백 콜레스테롤(low density lipoprotein-cholesterol, LDL-콜레스테롤)과 고비중 지질단백 콜레스테롤(high density lipoprotein-cholesterol, HDL-콜레스테롤)의 비는 대조군에 비해 증가되어 있었으며, HDL-콜레스테롤과 콜레스테롤의 비는 대조군에 비해 유의하게 낮았다. 3) 혈중 아포단백 B치는 대조군에 비해 상승되어 있었지만 아포단백 Al과 아포단백 B의 비는 차이가 없었고, 혈중 Lp(a)치는 PD군에서만 대조군보다 상승되어 있었다. 4) 혈중 Lp(a)치가 30 mg/dl 미만인 환아는 13명, 30 mg/dl 이상인 환아는 11명으로 이들 간에 연령, 비만지수, 투석방법, 투석기간은 차이가 없었으나 혈중 알부민은 Lp(a)가 상승된 환아들에서 감소되어 있었다. 5) 혈중 Lp(a)농도와 다른 지질 단백과의 비교에서 아포 단백 B만이 유의한 차이를 보였다. 결론 : 투석 치료중인 만성 신부전 소아에서 혈중 지질단백 이상이 관찰되었으며 특히 PD군에서는 혈중 Lp(a)치가 증가되어 있었다. 따라서 만성 신부전 소아에서 관상 동맥 질환의 위험도가 높을 것으로 사료되며 이에 대한 장기적이고 지속적인 관찰이 필요하다. Purpose : Chronic renal failure is often accompanied by severe dyslipidemia, a known risk factor for cardiovascular disease. Lipoprotein(a) [Lp(a)] has recently been characterized as a risk factor for atherosclerosis and thrombosis. Cardiovascular disease is the leading cause of death in adult patients on dialysis. However, there are only limited data available concerning risk factors for atherosclerosis in uremic children. We have measured serum levels of lipids, lipoproteins, apolipoproteins and Lp(a) in uremic children with maintenance dialysis. Methods : Ten uremic children with hemodialysis (HD) and 14 with peritoneal dialysis (PD) in our dialysis unit were included in this study. The mean age of HD patients was $162{\pm}59$ months and the male to female ratio was 7:3. The mean age and sex ratio of PD patients were $123{\pm}63$ months and 6:8, respectively. The levels of cholesterol, triglyceride, lipoproteins, apolipoproteins and Lp(a) were measured from serum sampled after 14 hours of fasting. The normal control levels were cited from 2 articles presenting the normal blood lipid and lipoprotein levels of primary school and middle school children in Korea. Results : There was no difference in age, sex ratio, body mass index and duration of dialysis between the HD and the PD group. The serum concentration of the cholesterol, triglyceride and apolipoprotein B were significantly elevated in dialysis patients compared with normal subjects. The serum level of Lp(a) was significantly elevated in only PD group. The serum Lp(a) level was below 30 mg/dl in 13 and above 30 mg/dl in 11 patients. The serum albumin level was significantly decreased in high Lp(a) group than in low Lp(a) group. Conclusion : The uremic children receiving dialysis reveal abnormal serum lipid and lipoprotein profiles. These results suggest that they have a higher risk for coronary heart disease, although there has been no clinical evidence of coronary heart disease at present. A long-term follow-up study of these children to clarify the suggestion should be started now.