• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.342-343
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• 2000

다양한 배출원을 통해 외부로 발산되는 악취유발물질이 생활환경에 미치는 영향을 객관적으로 조사하고 평가하기 위해서는 인간의 감각기관을 이용하는 관능측정법과 화학성분을 분석하는 기기분석법을 동시에 적용하는 것이 필요하다. 그러나 인간의 감각기관을 이용하여야 하는 관능측정법의 경우 판정인이 장시간에 걸쳐 악취현상을 평가할 수 없다는 한계를 갖고 있으며, 기기분석법의 경우도 측정방법의 특성상 장시간 동안 시료를 채취하기 어려운 문제점을 갖고있어 풍향 및 풍속 등 기상조건에 따라 순간적으로 감지되는 취기수준이 다른 악취현상을 명확하게 규명하는데 일정부분의 한계를 갖게된다. (중략)

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.7 s.178
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• pp.1748-1752
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• 2000

In this paper, the measurement technique of cutting temperatures of shear zone using implanted thermocouples is proposed in ball end milling. K-type thermocouple implanted in the hole of workpieces is directly cut in order to measure temperatures of the shear zone in cutting process. Experiments are performed for a nickel based superalloy(Inconel 718) using a ball nose end mill. The results show that the cutting temperature in shear zone is about 3200C at the cutting speed of 90m/min with dry.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1793-1797
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• 2003

After the micro turning lathe was developed in the last year by AMR Laboratory in Yeungnam university, a micromilling machine is developed for micro/meso machining. This machine is integrated with PZT-driven micro-sliders, micro-linear encoders, aerostatic spindle which has maximum 150,000 rpm. It is applicable to milling and drilling of micro scale. This paper presents the possibility of micro/meso machining and characteristics of micro end milling process by using micro machine. A machining of micro parts using 0.2 mm flat end mill was achieved by micro-milling machine. Experimental results show the machining capability and positional accuracy of this machine is good enough for machining micro parts.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.40-40
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• 2000

Generally a RF AGC controls the roll gap using the variation of rolling force caused by the roll eccentricity and the entry thickness of material, but these can not be classified. The Feed- forward AGC method, which controls the next stand roll 9ap by estimation the skid mark of the previous stand output thickness is needed to supplement the shortage of RF AGC. In this paper, an improved filtering method of skid mark which take account of the kinds of materials, the final objective thickness and the roll speed is proposed, In addition, an improved estimation method of control point using the speedometer and looper angle is suggested, Via simulation, the performance improvement of the suggested FF AGC method is verified.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.04a
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• pp.111-114
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• 2009

Production of rolled steel has been growing partly supported by the advancement of rolls and rolling mills. Aiming at the further improvement in roll performance, various new techniques such as centrifugal casting, double poured casting cast steel, special build-up making, etc. have been introduced in the field of roll manufacture in these several years. The present paper describes the development of horizontal cast rolls(sleeve and indefinite chilled roll) made by Hyundai Steel and the results of mill tests. The developed roils are contributing the improvement of final products.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.04b
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• pp.220-226
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• 1995

A study on the spalling causes of work roll for cold rolling was performed in the cold rolling mill. Performance of work roll is dependent to a great extent on spalling sothat both roll manufactures and users show great interest in spalling. So this paper shows that spalling origin on the roll surface. As being well known, spalling mostlyoccurred due to developing fatigue fracture originated a crack on a roll. But such spalling can be prevented by proper roll maintenance, The spalling accidents have sharply decreased since 1981 because of the use of ultrasonic test to detect cracks on a roll.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.453-454
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• 2006

This paper describes a processing verification technique for developing about end-milling cutters. Developed software is processing verification module for manufacturing. By using cutting simulation method, we can obtain center points of finding wheel via Boolean operation between a grinding wheel and a cylindrical workpiece. The obtained CL data can be used for calculating NC data. After then, we can simulate by using designed grinding machine and NC data. This research has been implemented on a commercial CAD system by using the API function programming. The operator can evaluate the cutting simulation process and reduce the time of design and manufacturing.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.10a
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• pp.326-331
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• 2000

This paper describes the statistical analysis techniques for the surface roughness assessment of polished surfaces. In experiments, the polishing process of the sample surfaces which are manufactured by ball end mill is consist of two steps; the cusp removal process and the surface finishing process. For the cusp removal process, the criterion of cusp removal was established from the power spectrum analysis to assess the change of the cusp removal rate. For the finishing process, the surface was polished by the rotational CBN tool and vibration wood tool. And the surface quality of polished surface was assessed using the functional parameters based on the statistical values of surface profiles. Consequently, the surface finish performance of the polished surface using the vibration wood tool was improved.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.33 no.3
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• pp.194-201
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• 1997

Recently with the rapid development in the industries such as an iron mill and chemical plants, these are enlarged by the use of the piping. This piping was encountered the stress corrosion cracking(SCC) because of stress by water pressure and residual stress of welding etc. under industrial water. In this paper, the behaviour of stress corrosion cracking on the weld zone of steel pipe piping water(SPPW) were investigated according to pre-heat before welding in natural seawater(specific resistance : 25$\Omega$-cm). The main results obtained are as follows :1) The stress corrosion cracking for SPPW and SB 41 is most ready to propagate in heat affected zone of weldment. 2) The SCC sensitivity of SPPW on weldment is more susceptible than that of SB 41. 3) The stress corrosion cracking growth of heat affected zone is delayed by the preheat and dry of base metal and electrode before welding.

• Transactions of Materials Processing
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• v.26 no.4
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• pp.228-233
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• 2017

In flat rolling mills, demands for precise process set-up and control are increasing than ever before. Consequently, it is imperative to establish a novel approach, which would provide valuable information regarding the detailed aspects of deformation behavior of the strip, and rolls during rolling. In this paper, we present a finite element (FE) approach for 3-D coupled analysis of the elastic-plastic deformation of the strip and the elastic deformation of rolls in the roll-stack of a mill stand.