Effect of Mn and C on Age Hardening of Fe–Mn–Al–C Lightweight Steels

Sung‑Won Park,Jun Young Park,Kyong Mox Cho,Jae Hoon Jang,Seong‑Jun Park,Joonoh Moon,Tae‑Ho Lee,Jong‑Ho Shin 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.3

The effects of Mn and C content on the age hardening of Fe–Mn–Al–C lightweight steels, which have austenitic or duplex(austenite and ferrite) microstructures, were investigated. An increase in Mn content induced a delay of the age hardeningthat is caused by the formation of intra-granular κ-carbides. In order to interpret the effect of Mn content, first-principlescalculations were conducted using the supercells of Fe24Al8C8,Fe24Al8C7,Fe24(Al7Mn)C8, and Fe24(Al7Mn)C7. The calculationsshowed that an increase in Mn content could be the source of the delay of the intra-granular κ-carbide formation bysuppressing C atom’ occupation of the vacancy at the body-centered site of L12. An increase in C content accelerated theformation of intra-granular κ-carbides, which induced the intense age hardening, and coarse inter-granular κ-carbides, whichresulted in significant decrease in impact absorbed energy due to inter-granular fracture.

조선대학교 의과대학의 유급제도 개선을 위한 예비조사

박종,박상기,박상학,도남용,송창훈,이승일,임성철 조선의대 1998 The Medical Journal of Chosun University Vol.23 No.1

Current Status of Industrial Waste Generation and Symbiosis Network in Gyeongsangbuk-do, South Korea

Jong-Hun Park,In-Gyung Jung,Jae-Gun Seo,Sang-Hyoun Kim 한국폐기물자원순환학회 2015 한국폐기물자원순환학회 학술대회 Vol.2015 No.05

This work aimed to analyze current status of by-products generation and industrial symbiosis network in Gyeongsangbuk-do, South Korea. Manufacturing sector of the province mainly consists of electronics, machinery, steel, metal-working industries. Gumi and Pohang have the 1st and 2nd largest worker population in the manufacturing sector. 21,950.7 ton/d of waste is generated from the industries in 2011, of which 82.2% is recycled. The industrial waste, which is not recycled, is mainly composed of sludge cake from domestic wastewater treatment plants, waste plastic, incinerator ash, and slag. Pohang is the largest generating city of both total and the non-recycled industrial waste in the province, and most of the waste is from Pohang steel industrial park. Symbiosis map in Pohang steel industrial park shows that most of the current material symbiosis in the industrial park is for waste refractories and slag.

젊은 남자에게 발생한 통상성 간질성 폐렴과 동반된 폐암 1예

박종숙,이준혁,박성우,장안수,박춘식,박재성,백상현,고은석,신화균 순천향의학연구소 2004 Journal of Soonchunhyang Medical Science Vol.10 No.2

Usual interstitial pneumonia(UIP) is relatively rare disease of lung parenchyme under the age of 50. Lung cancer is reported to occur as a complication of UIP, but has not been reported in young age patient with UIP in Korea. A 35-year-old man was admitted to the hospital because of dyspnea, cough and mild fever. He had been suffered from dyspnea during 3 years. The dyspnea worsened recent 1 month ago. He had been treated with pneumonia at another hospital during 4 months before this admission. Chest radiographs and High resolution CT showed subpleural and basal dominant reticular opacities in both lung with no change until now. He was smoker and his occupation was car engine-man dealing with benzene. UIP is suspected by history and radiologic findings. Operation for open lung biopsy was performed to obtain lung specimen via video-assisted thoracoscopic surgery. Patient's pathologic examination showed UIP combined with adenocarcinoma in RLL superior segment and posterobasal segment and RLL lobectomy was done. After operation, the patient has been in cancer free condition so far. We report a case of UIP combined with lung cancer in young man with brief review of the literature.

광조사 방식이 복합레진의 중합과 누출에 미치는 영향

박종진,박정원,박성호,박주명,권태경,김성교 大韓齒科保存學會 2002 Restorative Dentistry & Endodontics Vol.27 No.2

The aim of this study was to investigate the effect of light irradiation modes on polymerization shrinkage, degree of cure and microleakage of a composite resin. VIP^™ (Bisco Dental Products, Schaumburg, IL, USA) and Optilux 501^™(demetron/ Kerr, Danbury, CT, USA) were used for curing Filtek^™ Z-250(3M Dental Products, St. Paul., MN, USA) composite resin using following irradiation modes: VIP^™ (Bisco) 200mW/cm^2 (V2), 400mW/cm^2 (V4), 600mW/cm^2 (V6), Pulse-delay (200 mW/cm^2 3 seconds, 5 minutes wait, 600mW/cm^2 30seconds, VPD) and Optilux 501^™ (Demetron/Kerr) C-mode (OC), R-mode (OR). Linear polymerization shrinkage of the composite specimens were measured using Linometer (R&B, Daejeon, Korea) for 90 seconds for V2, V4, V6, OC, OR groups and for up to 363 seconds for VPD group (n=10, each). Degree of conversion was measured using FTIR spectrometer (IFS 120 HR, Bruker Karlsruhe, Germany) at the bottom surface of 2 mm thick composite specimens. V2, V4, V6, OC groups were measured separately at five irradiation times (5, 10, 20, 40, 60 seconds) and Or, VPD groups were measured in the above mentioned irradiation modes (n=5, each). Microhardness was measured using Digital microhardness tester (FM7, Future-Tech Co., Tokyo, Japan) at the top and bottom surfaces of 2mm thick composite specimens after exposure to the same irradiation modes as the test of degree of conversion(n=3, each). For the microleakage test, class V cavities were prepared on the distal surface of the ninety extracted human third molars. The cavities were restored with one of the following irradiation modes: V2/60 seconds. V4/40 seconds, V6/30 seconds, VPD, OC and OR. Microleakage was asessed by dye penetration along enamel and dentin marigns of cavities. Mean polymerization shrinkage, mean degree of conversion and mean microhardness values for all groups at each time were analyzed using one-way ANOVA and Duncan's multiple range test, and using chisquare test for microleakage values. The results were as follows: ·Polymerization shrinkage was increased with higher light intensity in groups using VIP^™(Bisco) : the highset with 600mW/cm^2, followed by Pulse-delay, 400mW/cm^2 and 200mW/cm^2 groups. The degree of polymerization shrinkage was higher with Continuous mode than with Ramp mode in groups using Optilux 501^™ (Demetron/Kerr). ·Degree of conversion and microhardness values were higher with higher light intensity. The final degree of conversion was in the range of 44.7 to 54.98% and the final microhardness value in the range of 34.10 to 56.340. ·Microleakage was greater in dentin margin than in enamel margin. Higher light intensity showed more microleakage in dentin margin in groups using VIP^™ (Bisco). The microleakage was the lowest with Continuous mode in enamel margin and with Ramp mode in dentin margin when Optilux 501^™ (Demetron/Kerr) was used.

Current Status of Industrial Waste Generation and Symbiosis Network in Gyeongsangbuk-do, South Korea

( Jong-hun Park ),( In-gyung Jung ),( Jae-gun Seo ),( Sang-hyoun Kim ) 한국폐기물자원순환학회(구 한국폐기물학회) 2015 한국폐기물자원순환학회 춘계학술발표논문집 Vol.2015 No.-

This work aimed to analyze current status of by-products generation and industrial symbiosis network in Gyeongsangbuk-do, South Korea. Manufacturing sector of the province mainly consists of electronics, machinery, steel, metal-working industries. Gumi and Pohang have the 1st and 2nd largest worker population in the manufacturing sector. 21,950.7 ton/d of waste is generated from the industries in 2011, of which 82.2% is recycled. The industrial waste, which is not recycled, is mainly composed of sludge cake from domestic wastewater treatment plants, waste plastic, incinerator ash, and slag. Pohang is the largest generating city of both total and the non-recycled industrial waste in the province, and most of the waste is from Pohang steel industrial park. Symbiosis map in Pohang steel industrial park shows that most of the current material symbiosis in the industrial park is for waste refractories and slag.

조선대학교 의과대학 유급제도 개선을 위한 예비조사

박종,박상기,박상학,도남용,송창훈,이승일,임성철 朝鮮大學校 附設 醫學硏究所 1998 The Medical Journal of Chosun University Vol.23 No.1

This is a pilot study to improve the flunk system, a self-reported questionnaire survey was done by 58 professors among a total of 94 professors at Chosun University Medical School in December 1997. The results were as follows : 1. In regard to the student's residence, 69% of professors answered that the current system was appropriate. For a proper method of flunking. 46.6% of the professors agreed to the introduction of retesting by the Academic Affairs Department and 44.8% of the professors agreed to the evaluation of academic achievement of each subject. 2. Sixty-seven point two percents of professors agreed to the changing of time of flunk. 43.1% felt at the end of course, 24.1% felt at midterm, and 25.9% felt that the current system. 3. In regard to flunking, 34.5% of professors thought the current system-if a student receives an F grade in to be one subject, he/she was flunked-was sufficient, but 65.6% of the professors felt needed there improvement. The method of improvement was considered was losing more than two credits-fail(32.8%), and losing more than four credits-fail(10.3%). 4. Eighty-four point five percent of the professors agreed to the necessity of flunking by grade point average(GPA) and 77.6% of the professors answered that the students who must re-register should take all designated subjects. 5. Seventy-two point four percent of the professors opposed summer or winter courses for students who flunk and 51.7% of the professors opposed the necessity of a management system for students. In conclusion, the professors in Chosun University Medical College recognized the necessity of improving the flunk system, especially, the time, method and record keeping. So a concrete follow-up study needed to improve the flunk system.

차량 재도색용 청색 페인트의 분석

박성우,손성건,박하선,박성지,정영호,홍성욱,박종신 內務部 國立科學搜査硏究所 2002 國立 科學 搜査 硏究所 年報 Vol.34 No.-

한국인 성인 남성 폐쇄성수면무호흡 환자의 측모 두부 방사선계측학적 비교

황상희,박인숙,남기영,김종배,조용원,서영성,안병훈,박신구,박효상 대한치과교정학회 2008 대한치과교정학회지 Vol.38 No.3

본 연구는 비만도에 따른 한국인 남성 폐쇄성수면무호흡 환자의 측모 두부 방사선계측학적 특성을 파악하기 위하여 시행되었다. 이를 위하여 계명대학교 의과대학 동산의료원 수면클리닉에 수면장애를 주소로 내원하여 수면다원검사 후 치과에서 측모 두부방사선계측사진 촬영을 한 87명의 성인 환자들을 체질량지수(BMI)와 수면무호흡지수(AHI)에 따라 비비만 단순코골이군(Non-obese, simple snorers), 비만 단순코골이군(Obese, simple snorers), 비비만 수면 무호흡군(Non-obese, OSA patients), 비만 수면무호흡군(Obese, OSA patients)의 4군으로 나누어 비교하였다. 그결과, 4군 중 비만 수면무호흡군의 수면무호흡지수가 가장 컸으며, 비만 수면무호흡군보다 비비만 수면무호흡군의 하악각이 더 크고 혀 길이는 더 작았다. 또한, 비비만 수면무호흡군보다 비만수면무호흡군의 설골이 더 전하방에 위치하였고, 수면무호흡지수에 영향을 미치는 기여 인자는 비만 수면무호흡군에서는 혀 길이, 비비만 수면무호흡군에서는 설골의 후방위치였다. 이처럼 비만 수면무호흡 환자와 비비만 수면무호흡 환자의 측모 두부방사선계측학적 특성과 기여 인자가 다르게 나타나므로, 치료방법도 따라서 다르게 선택해야 할 것이다. 비만 수면무호흡 환자들에게는 먼저 체중감량이 권고되어야 할 것이고, 비비만 수면무호흡 환자들은 폐쇄부위에 따라 구강 내 장치나 Nasal CPAP (continuous positive airway pressure), UPPP (uvulopalatopharyngoplasty) 등이 추천될 수 있을 것이다. Objective: The purpose of this study was to compare the cephalometric measurements of obese and non-obese Korean male patients with obstructive sleep apnea syndrome (OSA). Methods: Eighty-seven adults who had visited the Sleep Disorder Clinic Center in Keimyung University, Daegu, Korea were examined and evaluated with polysomnography (PSG) and lateral cephalogram. They were divided into 4 groups (non-obese simple snorers, obese simple snorers, non-obese OSA patients, obese OSA patients) according to AHI (Apnea-Hypopnea Index) and BMI (Body Mass Index). Results: The obese OSA group had the highest AHI among the 4 groups. The non-obese OSA group had a significantly steeper mandibular angle and shorter tongue length than the obese OSA group. The hyoid bone of the obese OSA group was positioned anterior and inferior as compared with the non-obese OSA group. Multiple regression analysis showed that tongue length in the obese OSA group and retroposition of hyoid bone in the non-obese OSA group were significant determinants for the severity of AHI. Conclusions: From a cephalometric point of view, the obese and non-obese pateints with OSA may be characterized by different pathogeneses. Therefore, they have to be managed by individualized treatment. For the obese OSA patients, weight control must be advised as a first choice and for the non-obese OSA patients, oral appliance, nasal CPAP, UPPP and others could be chosen according to the obstructive sites.

한반도 서남부 지역에 서식하는 섬휘파람새(Cettia diphone cantans) 번식기 울음소리 연구

김성진(Sung-Jin Kim),박종길(Jong-Gil Park),홍길표(Gil-Pyo Hong),채희영(Hee-Young Chae) 한국조류학회II 2008 한국조류학회지 Vol.15 No.2

포획조사를 실시하여 동정된 개체를 대상으로 섬휘파람새(Cettia diphone cantans)의 번식기 울음소리를 녹음하였으며 다도해(홍도), 월출산(춘양리, 도갑사, 금릉경포대)으로부터 총 8개체 240 song을 녹음 분석하였다. 조사지역별 번식기 울음소리의 동질성 검사를 통해 통일 집단 여부 분석결과 다도해(홍도 n=3; 72 song)와 월출산(춘양리 n=3; 80 song, 도갑사 n=1; 68 song, 금릉경포대 n=1; 20 song)에서 모든 조사지역의 개체들이 동일 집단을 형성하지 않는 것으로 나타났으며, 동일 장소에서 녹음한 다도해 홍도 3 개체와 월출산 춘양리 3 개체만이 각각 동일 집단을 형성하였다. 번식기 울음소리의 유형은 다도해(홍도) 5 개, 월출산(춘양리) 5 개, 월출산(도갑사) 4 개, 월출산(금릉경포대) 4 개로 나타났다. 홍도와 춘양리 두 집단의 각각의 상관분석 결과 NNWP와 NNSP, COM이 강한 음의 상관관계(홍도 R=-0.97, 춘양리 R=-0.95)를 나타내었으며, NNSP와 COM이 일치하는 것(두 집단 모두 R=1.00)으로 나타나 본 연구에서 녹음한 섬휘파람새 번식기 울음소리의 경향을 알 수 있었다. 본 연구에서 녹음한 섬휘파람새 전체의 번식기 울음소리는 일관되게 A, B 유형의 두 가지로 분류할 수 있었다. 번식기 울음소리의 두 가지 유형을 T 검정 결과 NNWP, MIWP, DWP, NNSP, MASP, DSP, COM 요인에서 차이가 나타났다(P<0.01). 번식기 울음소리 유형의 조사지역별 및 각 집단 간의 차이는 동종 개체군간의 경쟁 및 번식 전략의 선택과 같은 생태학적 요인과 관련이 있는 것으로 판단되며, 번식기 울음소리 발달상의 변이에 의해 개체별 변이가 나타나는 것으로 판단된다. Communicative interaction are the essence of all animal societies, so it is appropriate to examine communication as a way to gain insight into social structure and thereby generate hypotheses about genetic structure. It is worth pointing out a suggestive pattern in the class Aves, with respect to the approach to genetic population structure by study of vocal communication. Last study of Japanese Bush Warbler Cettia diphone overlooked for distribution and song structure between subspecies. This study is Japanese Bush Warbler Cettia diphone cantans distribution and song structure of the population in South-West Korea. Population distribution researched by banding. Identified Japanese Bush Warbler Cettia diphone cantans record total 8 individuals 240 songs in Hong island, Dadohae National Park and Chunyang-ri; Dogap temple; Kumneung Kyungpo post, Wolchulsan National Park. song homogenity (MANOVA) analyzed each study area. Only the individual which records from identical place formed identical group. Each study site has 5 song types in Hong island and Chunyang-ri, 4 song types in Dogap temple and Kumneung Kyungpo post. But analyzed of all Japanese Bush Warbler Cettia diphone cantans song divided A or B type with parameters (NNWP, NNSP, and COM). Paired t-test against A or B type of song differed from most parameter significant (P<0.01). We analyzed correlation between Hong Is. and Cunyang-ri in sample size, each region was related to negative correlation (Hong Is.: R=-97, Chunyang-ri: R=-95; P<0.01). Moreover, we analyzed NNSP and COM which are accord with correlation (R=1.00). Difference of each study site of song type are thought to intra-species male-male competition and selection of breeding strategy. In addition, repertoire size difference in each site are thought to received the effect of the variation of song development and cultural mutation. Variable variation, that even only affected to song type and repertoire size, and so Japanese Bush Warbler Cettia diphone cantans song study have to much investigation.