자동차용 피스톤 핀의 전.후방압출에서 유동제어에 관한 실험적 연구

박종남,박태준,김동환,김병민,Park, Jong-Nam,Park, Tae-Joon,Kim, Dong-Hwan,Kim, Byung-Min 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.7

In cold forging of piston-pin for automobile parts, the flow defect appears by the dead metal zone. This appearance evidently happens in products with a thin piercing thickness for the dimension accuracy and the decrease of material loss. The best method that can prevent flow defect is removing dead metal zone. The purpose of this study is to investigate the material flow behavior of forward-backward extruded piston-pin through the relative velocity ratio and the stroke control of upper moving punch & container using the flow control forming technique. The finite element simulations are applied to analyse the flow defect, then the results are compared with the plasticine model material experiments. The model experiment results are in good agreement with the FE simulation ones.

마멸모델을 이용한 금형마멸 예측에 관한 연구

박종남,Park, Jong-Nam 한국금형공학회 2013 한국금형공학회지 Vol.7 No.1

During the cold forming, due to high working pressure acting on the die surface, failure mechanics must be considered before die design. One of the main reasons of die failure in industrial application of metal forming technologies is wear. The mechanisms of wear are consisted of adhesion, abrasion, erosion and so on. Die wear affects the tolerances of formed parts, metal flow, and costs of process. The only way to control these failures is to develop a prediction method on die wear suitable in the design state in order to optimize the process. The wear system is used to analyse 'operating variables' and 'system structure'. In this study, with AISI D2, AISI 1020, AISI 304SS materials, a series of the wear experiments of pin-on-disk type to obtain the wear coefficients from Archard's wear model and the upsetting processes are carried out to observe the wear phenomenon during the cold forming process. The analysis of upsetting processes are performed by the rigid-plastic finite element method. The result of the analysis is used to investigate the die wear the processes, and the analysis simulated die wear profiles are compared with the experimental measured die wear profiles.

선삭가공시 Ti-6Al-4V 합금의 절삭특성에 관한 연구

박종남,조규재,이승철,Park, Jong-Nam,Cho, Gyu-Jae,Lee, Seung-Chul 한국기계가공학회 2004 한국기계가공학회지 Vol.3 No.4

The titanium has many superior characteristics such as specific strength, heat resistance, corrosion resistance, organism compatibility, non-magnetic and etc. and their quantity are abundant. This study performed turning operation of Ti-6Al-4V alloy using the TiAlN coated tool which was treated with PVD. Experimental works were also executed to measure cutting force, chip figuration and surface roughness for different cutting conditions. As a result of study, tool wear was serious at the condition over 100m/min of cutting speed. The excellent cutting condition of cutting depth was at 1.0mm.

고속도공구강을 이용한 GFRP 가공특성에 관한 연구

박종남,정성택,조규재,Park, Jong-Nam,Jeong, Seong-Taek,Cho, Gyu-Jae 한국기계가공학회 2003 한국기계가공학회지 Vol.2 No.2

Composite materials are widely used to make all kinds of machine parts, internal and structural materials of cars, aerospace industries, building structures, ship materials, sporting goods and others. It is worth the while to use composite materials as various substitutions when compared With others. But the use is limited in the field of the mechanical processing because of its difficulties in cutting. The surface roughness of in and out in the hole processing was discussed after cutting the GFRP with HSS drill in the vertical machining center. And it is observed that as it processed more, the powdered chip may be got more than the fluid type long chip.

Ti-6Al-4V합금의 절삭성에 관한 연구

박종남,김재열,조규재,Park, Jong-Nam,Kim, Jae-Yoel,Cho, Gyu-Jae 한국생산제조학회 2010 한국생산제조학회지 Vol.25 No.3

The Titanium has many superior characteristics which are specific strength, heat resistance, corrosion resistance, organism compatibility, non-magnetic and etc. and their quantity are abundant. this study performed turning operation of Ti-6Al-4V alloy using the TiAlN Coated Tool which treated Physical Vapor Deposition. Experimental works are also executed to measure cutting force, tool wear, chip figuration and surface roughness for different cutting conditions. As a result of study. Cutting depth influences on the cutting force much more than the feed rate and the value of the cutting force is the most stable at the depth of 1.0mm. And tool wear was serious at over 100m/min of cutting speed and cutting condition was excellent at 1.0mm of cutting depth.

광역지질도 작성을 위한 ISODATA 응용

박종남 ( Jong Nam Park ),서정희 ( Jung Hee Suh ) 大韓遠隔探査學會 1989 大韓遠隔探査學會誌 Vol.5 No.2

The ISODATA method, which is one of the most famous of the square-error clustering methods, has been applied to two Chungju multivariate data sets in order to evaluate the effectiveness of the regional lithological mapping. One is an airborne radiometric data set and the other is a mixed data set of the airborne radiometric and Landsat TM data. In both cases, the classification of the Bulguksa granite and the Kyemyongsan biotite-quartz gneiss are the most successful. Hyangsanni dolomitic limestone and neighboring Daehyangsan quartzite are also classified by their typical lowness of the radioactive intensities, though it is still confused with some others such as water-covered areas and nearby alluvials, and unaltered limestone areas. Topographically rugged valleys are also classified as the same cluster as above. This could be due to unavoidable variations of flight height and the attitude of the airborne system in such rugged terrains. The regional geological mapping of sedimentary rock units of the Ockchun System is in general confused. This might be due to similarities between different sediments. Considarable discrepancies occurred in mapping some lithological boundaries might also be due to secondary effects such as contamination or smoothing in digitizing process. Further study should be continued in the variable selection scheme as no absolutely superior method claims to exist yet since it seems somewhat to be rather data dependent. Study could also be made on the data preprocessing in order to reduce the erratic effects as mentioned above, and thus hopefully draw much better result in regional geological mapping.

프로그레시브 금형의 품질관리를 위한 정도관리 시스템 개발

박종남(Park, Jong-Nam) 한국산학기술학회 2014 한국산학기술학회논문지 Vol.15 No.9

금속의 표면관리는 공구 현미경이나 표면 조도 측정기를 이용하고 있다. 이러한 방법은 구조적인 문제로 인하여 생산현장에서 금형의 표면 상태 확인을 하기에는 효율성이 떨어진다. 이런 이유로 완성된 금형의 노후화에 따른 마모, 흠집 및 표면 상태를 관리할 수 있는 분석시스템 또는 측정시스템이 필요하다. 본 연구는 금형이나 가공품의 자동분석 및 기준화 를 위한 표면상태 분석 소프트웨어를 개발하였다. 소프트웨어는 기본적으로 원, 점, 선 등의 요소들을 측정할 수 있게 개발하 였으며, 캡처한 사진을 3차원 이미지로 구현하여 금형에 생긴 홈의 깊이와 단면 프로파일을 추정할 수 있도록 중점을 두었다. 실험분석결과 표면 조도는 93.2%이상의 정확도를 나타냈으며, 조명밝기에 대한 표면 조도의 최대편차는 3㎛ 이내로 매우 정밀하였다. 이런 결과로 금형의 측정 및 표면분석을 통한 품질관리의 효율성을 확인 할 수 있었다. The surface management of metals was performed with a tool microscope or surface roughness measurement instruments. These methods were not efficient for checking the surface status of the die in the production field. For this reason, an analysis system or measurement system to monitor the wear, defects and surface status as a die ages is required. This study, developed surface analysis software for automatic analysis and standardization of a die or processed products. Software was designed to measure the basic features, such as circles, dots, and lines. The captured images were rendered as three-dimensional representations so that the depth of the grooves on the die and segmental profiles could be estimated. As a result of experimental analysis, the surface roughness was measured with an accuracy more than 93.2%, and the maximum deviation in the surface roughness for the brightness of the lighting was within 3㎛. The confidence in the device's precision was assured. These results show quality control through efficient surface analysis.

울산지역 비금속광물 및 암석 분류를 위한 원격탐사 자료처리

박종남 ( Jong Nam Park ),박인석 ( In Seok Park ) 大韓遠隔探査學會 1991 大韓遠隔探査學會誌 Vol.7 No.2

Feature enhancement combined with some pattern recognition techiques were applied to the Remote Sensing Data for geological mapping with particular emphasis on non-metallic ore deposits and their related geologies. The area chosen is north of Ulsan, the size of which is about 400km2. The geology of the area consists mainly of volcanics, volcanic sediments and clastic sediments of Miocene age, underlain by the Kyungsang sediments of Cretaceous age. The mineralization occurs in tuffs or along the bedding plane of tuffaceous sediments, the main products of which are Kaolinite and Bentonite. The outcrops or mine dumps in the study area were most effectively extracted on the histrogram normalized image of TM Band 1 and 2, due to their high reflectivity. These may be confused with some artificial features, like slate roof complex of the poultry farm or cement ground, which should be classified by field checking. Detailed examination of enhancment image combined with pattern recognition techniques made enable to classify different rocks and thereby extract volcanic products which are mainly related to non-metallic ore deposits in the study area.

Valve Point 효과가 고려된 경제급전에서의 유전알고리즘 응용

朴鍾男(Jong-Nam Park),朴璟遠(Kyung-Won Park),金志鴻(Ji-Hong Kim),金鎭吾(Jin-O Kim) 대한전기학회 1999 전기학회논문지A Vol.48 No.3

급성 호산구성 폐렴 3 예

박종남(Jong Nam Park),이병건(Byung Kyung Lee),김대현(Dae Hyun Kim),김기환(Ki Whan Kim),장태원(Tae Won Jang),정만홍(Maan Hong Jung),정규식(Kyu Sik Jung) 대한내과학회 1996 대한내과학회지 Vol.51 No.2

Three previously healthy patients presented with an acute febrile illness, severe hypoxemia (PaO2<60 mmHg), diffuse pulmonary infiltrates, an increased number of eosinophils(mean 74%) in bronchoalveolarlavage fluid, and an absence of infection and previous atopic illness. The patients rapidly improved after treatment with or without corticosteroid therapy, and none have relapsed since the steroid was discontinued. These findings were consistent with acute eosinophilic pneumonia. We present three cases of acute eosinophilic pneumonia and review the pertinent literature.