[논문]Operational Characteristics of CO2 Laser Adopted by Superposing-Discharge

Hee-Je Kim,Hyun-Ju Chung,Byoung-Dae Min,Jong-Han Joung,Sung- lun Park 釜山大學校生産技術硏究所 2003 生産技術硏究所論文集 Vol.62 No.-

오늘날 현저한 CO2 레이저의 응용 추세에 발맞추어 보다 다양한 형태의 출력 제어 기술이 대두되고 있다. 본연구에서는multi-Pulse Superposing-Discharge 기술을 이용하여 다양한형태의 CO2 레이저의 펄스를 성형 하였다. 펄스 성형을 위한 방법으로 PIC one-chip microprocessor를 이용하여 삼중 PFN 모률의 SCR을 각각 고유의 지연시간을 가지도록 제어하였다. 실험에 사용된 삼중 PFN 모률의 전원 회로는 각각 캐패시터 인덕터,SCR,고압 펄스 트랜스 그리고 고압 트랜스 2차측에 브릿지 정류기로 구성 하였다. 고압 펼스 트랜스의 1차측을 제어하므로서 PFN 모률의 동작을 저 전압에서 수행 할 수 있다. 트랜스의 2차측에 연결된 전파 정류기는 펄스 에너지를 부하에 지속적으로 전달한다. 본 연구에서는 삼중 PFN 모률의 각각의 SCR을 다른 시간 가격을 두고 트리거 하므로서 다양한 Long pulse shaping을 실현하였다. 또한 약 250-1000μs 의 주기를 가지는 다양한 펄스형 레이저 빔을 얻었다.

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.

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.

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.

보문 : Polyethylene Film포장이 포도 Sheridan의 저장력에 미치는 영향

남상영(Sang Young Nam),김경미(Kyoung Mi Kim),박종천(Jong Chun Park),주선종(Seon Jong Joo),정재현(Jai Hyun Jung) 한국식품저장유통학회(구 한국농산물저장유통학회) 1997 한국식품저장유통학회지 Vol.4 No.1

Effects of Pilger Rolling and Heat Treatment on Microstructure and Corrosion Resistance of Ag-electroplated 304 Stainless Steel Tubes

Hyun Park,Woo‑Jin Lee,Jae‑Han Son,Han‑Kyun Shin,Sung‑Kyu Hong,Hyo‑Jong Lee 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.8

We introduce a cost-effective method that combines electroplating with metal cold working processes to manufacture compositetubes with robust corrosion resistance. First, a 3-step electroplating process was developed to form an adhesive anduniform Ag coating on the outer wall of a 304 stainless steel tube. The process consisted of a Ni-strike step for removing thepassivation layer of the initial 304 tube, Cu deposition for smoothing the surface by adding a buffer layer, and Ag deposition. To reinforce the interfacial adhesion between the electroplated layers and the 304 tube and increase the area of the Ag coating,a pilger rolling or pilger rolling + heat-treatment process was performed after the Ag electroplating process. Scanningelectron microscopy of the composite tubes after each process indicated that the as-deposited Ag coating changed fromhaving a rough to smooth surface after only pilger rolling and with additional heat treatment. Electron backscatter diffractionanalysis of the microstructures and textures of the tubes revealed that dynamic recrystallization occurred extensively duringpilger rolling, resulting in the formation of a relatively defect-free grain structure without heat treatment. Furthermore,electrochemical polarization curves determined that the Ag-coated composite tubes are superior to the uncoated 304 tubein terms of corrosion resistance under Cl−atmosphere, owing to the formation of a AgCl passivation layer during testing. Surface analysis of the composite tubes suggests that the properties of the AgCl passivation layer are related to the grainsize of the Ag coating and the density of plastic-deformation-induced defects.

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.

지역냉방 시스템용 초고효율 판형 열교환기 개발에 관한 연구

박재홍(Jae-Hong Park),임혁(Hyug-Lim),조성열(Sung-Youl Cho),강인성(In-Sung Kang),김정규(Jung-Kyu Kim),허인은(In-Eun Hur),고성규(Seong-Kyu Ko),곽승식(Sung-Sik Kwak),김종재(Jong-Jae Kim) 한국마린엔지니어링학회 2010 한국마린엔지니어링학회 학술대회 논문집 Vol.2010 No.10

Plate heat exchanger consists of thin, rectangular, pressed sheet metal plates that are sandwiched between full peripheral gaskets and clamped together in a frame. The frame has a fixed end-cover plate, fitted with the connecting ports, which is bolted together with a movable cover plate to hold the embossed plates in between; the top and bottom carrying bars allow proper alignment of the plate stacks. When compared with the well-established shell and tube heat exchangers, the plate heat exchanger shows a lot of advantages like high NTU values, compactness, low cost, multi duties and reduced fouling etc. Plate heat exchangers are often used to transfer heating or cooling water which is produced in the energy production( district heating or district cooling) facilities to residential areas and industrial parks. The district cooling systems of Middle East are the biggest market of plate heat exchanger, but the technical specifications for cooling system are different from the domestic one. To achieve its specifications, the new plate heat exchanger was developed, and its thermal performance results are introduced in this paper.

스노우파크 공조 및 폐열회수 시스템

김영한(Kim Young Han),박성빈(Park Sung Bin),정성화(Jung Sung Hwa),조현근(Jo Hyun Guen),조종선(Cho Jong Sun) 대한설비공학회 2013 대한설비공학회 학술발표대회논문집 Vol.2013 No.6

The presentation is the HVAC system in the Goyang ONEMOUNT snow park. The content consist of Architectural overview, design criteria, heat source equipment and air-conditioning system and waste recovery system explanation.

Distribution of the Fairy Pitta (Pitta nympha) in the South Korea: A focus on protected areas

Gil-Pyo Hong(홍길표),Jae-Hoon Kim(김재훈),Seul-Gi Seo(서슬기),So-Yeon Cho(조소연),Bo-Yeon Hwang(황보연),Jong-Hyun Park(박종현),Seung-Yeon Lee(이승연),Ga-Young Kim(김가영),Wan-Hee Nam(남완희),Ha-Cheol Sung(성하철) 한국조류학회 2021 한국조류학회지 Vol.28 No.2

국내 팔색조(Pitta nympha) 분포 현황을 알아보고자 전국 국립공원 등 보호지역 중심으로 총 19개 지역을 조사하였고, 전문가 네트워크를 통해 자료를 보강하였다. 전국 19개 지역을 조사한 결과 북한산, 지리산 등 내륙지역 7개 국립공원에서는 팔색조가 확인되지 않았고, 경남 거제, 남해, 해남, 장흥 고흥 등 남해안과 인접한 12개 지역에서 팔색조 서식이 확인되었다. 또한 전문가 네트워크를 통해 수집한 팔색조 출현 위치 정보 82건을 분석한 결과, 전국 8개 광역지자체 모두 팔색조 서식이 확인되었고, 내륙지역(26.8%)보다 해안지역(73.2%)에서 더 많이 출현하였다. 연구 결과를 종합해보면, 우리나라의 팔색조는 주로 제주도와 남해안 지역을 중심으로 많이 분포하며, 그 보다 적은 개체수가 내륙 지역에 넓게 분포하고 있는 것으로 나타났다. The present study investigated the current distribution of Fairy Pitta (Pitta nympha) in South Korea. A total of 19 study areas, including protected areas such as national and provincial parks in South Korea were surveyed, and additional data obtained from an expert network. According to the results, Fairy Pitta was absent in seven inland national parks, including Mt. Bukhan and Chiri parks. Fairy Pitta inhabited 12 areas near the southern coast of South Korea, including Geoje, Namhae, Haenam, Jangheung, Goheung, and Gyeongnam Province. The analysis results of 82 datasets obtained from experts with regard to the locations where Fairy Pitta have been spotted showed that the bird inhabits all the eight metropolitan regions in South Korea, and is more frequently spotted in coastal areas (73.2%) than in inland areas (26.8%). The findings demonstrate that Fairy Pitta is mainly distributed in Jeju Island and the southern coast of South Korea, and is distributed in inland areas at relatively lower numbers.