• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1997년도 춘계학술대회논문집
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• pp.273-280
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• 1997

Rotary swaging is a process for reducing the cross-sectional area or changing the shape of bar, tube or wires by repeated radial blows with one or more parirs of opposed dies. The present study is concerned with investigation the effect of process parameters upon product quality(hardness, roughness, precision of dimension). To enhance the product quality, experimental works are carried out for some process parameters such as forming speed, billet shape, lubrication, reduction of area and ratio of t/D. Rod shift formed by RSM25 under cold conditions has good surface quality, hardness and precision of dimension. The recommendable process conditions are suggested for solid and tubular products.

• 골판지포장물류
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• 통권78호
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• pp.83-89
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• 2008

이 매뉴얼에는 놀라운 기술적 비밀 또는 특허가 될 만한 정보가 있는 것은 아니다. 대부분의 정보는 골판지 산업계 내에서 수십년 동안 존재해왔던 것들이다. 이 메뉴얼은 단지 현재 존재하고 있는 이런 정보들을 군에서 사용되는 유지관리 시스템에 맞추어 하나의 논리적인 형식으로 압축한 것에 지나지 않는다. 하지만 이 매뉴얼이 나오기 까지 물신양면으로 도움을 주신 몇몇 분들에게 감사를 전하고자 한다. 첫 번째로 미육군에 감사하고 싶다. 유지관리 초년장교로서 나는 심지어 가장 오래된 골동품인 1959년형 2.5톤 트럭조차도 수 십년간 최적의 수준으로 달리게 만드는 미육군의 매우 조직적이고 단순한 유지관리 시스템을 보고 매우 놀랐었다. 이 매뉴얼 안에 있는 조직적인 틀은 그러한 경험의 산물이다. 나에게 많은 훈련을 시켜 주었고 정보를 준 웨스트베코사(Westvaco Corporation)의 짐버트(Jim Burt)에게 감사하지 않을 수 없다. 이 책에 소개되어 있고 현재 골판지 산업계에서 사용되는 조정에 관한 대부분의 정보는 스톤 컨테이너사(Stone container corporation)의 던드래쥐(Don Drage)의 공이 크다. 이외의 정보는 종이판지 포장잡지(Paperboard packaging magazine)의 에드릴레이(Ed Riley)와 같은 지도자에 의해 쓰여진 기사들에서 얻어진 것이다. L.A. 사우어사(L.A. Saur Corporation)와 같은 장비와 부품회사들 또한 그들 전문분야에서의 가장 최신의 정보를 제공해 주었음을 밝히는 바이다.

• 유공압시스템학회논문집
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• 제1권1호
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• pp.17-22
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• 2004

The goal of this paper is to improve the position control performance of pneumatic rotary actuator with variable brake using Magneto-Rheological Fluid. The air compressibility and the lack of damping of the pneumatic actuator bring the dynamic delay of the pressure response and cause the oscillatory motion. In this study, a variable rotary brake comprising Magneto-Rheological Fluid is equipped to the joint of a pneumatic manipulator. Experiments of step response have proved that the transient response of the manipulator could be improved compared with that of the conventional control algorithm by using a phase plane switching control algorithm.

• 한국기계가공학회지
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• 제8권4호
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• pp.61-68
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• 2009

This paper presents the numerical analysis of process of sludge drying to know the characteristics of design parameters and develop the new process plant. Finite volume method and $k-{\varepsilon}$ turbulence model were used to analogy the sludge drying furnace. It has been attempted to perform the disposal of sewage sludge such as simple reclaiming and dumping in sea and incineration. Currently, these methods are restricted by national or international government regulations. The drying process is adopted as an effective method for sewage sludge treatment. However sewage sludge makes it difficult to treat with a large volume at the real drying process plant because of its own complicated physical, chemical, and thermal properties. The final design value of moisture content with 10% of the dried sludge can be obtained through the simulated outputs in this study.

• 한국주조공학회지
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• 제20권6호
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• pp.407-418
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• 2000

The effect of various factors on the results of degassing of AC4C aluminum alloy melt by using rotary degasser were investigated. The difference between the effects of nitrogen gases of commercial pure and high purity grades on the degassing results was not significant. The optimum degassing condition was obtained. The effect of holding and degassing temperature was not significant, either. The result of degassing was deteriorated by the modification treatment of eutectic silicon, meanwhile improved by the grain refining. The effect of the latter was stronger than that of the former when the melt was treated simultaneously. The volume fractions of hydrogen porosity of the castings obtained from the molds with water moisture such as natural and green sand molds were much higher than those from the molds without that such as pep-set and $CO_2$ molds.

• 한국연소학회지
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• 제22권4호
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• pp.9-18
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• 2017

This paper is to suggest a simple flame model for the analysis of an internal flame of rotary kilns and to present the application cases. Reaction rates in the multi combustion stages of the selected solid fuel were calculated considering the reaction rates with the Arrhenius type equations. In addition, primary and secondary air flow arrangement were considered. As a simple application case, the combustion trends according to the different solid fuels were described. Improved operating conditions as related with the fuel characteristics were shown to be important for the stable combustion characteristics and the performance of the reactors as defined by the exit temperature of the solid materials.

• 한국환경농학회지
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• 제15권3호
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• pp.355-361
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• 1996

The Purpose of this study was to investigate the effect of the Change in the operating conditions on rotary turning compost plants. The major parameters investigated were moisture content and mixing of the sawdust and pig farm wastewater. Pig farm scale composting plants with mixing rotary were used in this study. Wastes used for the study were sawdust, pig manure, urine and wastewater. When the moisture content was 75%, the compost product obtained from the plants had better physical characteristics than that obtained from the plants with moisture contents of 70%, 80% and 85%.(two a day mixing). When the turning was twice a day, the compost product obtained from the plants had better characteristics than that obtained from non-mixing.(moisture content 75%). C/N ratio, pH value and coliform bacterial population were stable in the compost.

• 한국생산제조학회지
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• 제21권6호
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• pp.926-931
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• 2012

Rotary bar was cutting tool being in use for deburring scale after welding metal and for eliminating sharp edges. It was necessary to develop exclusive 6-axis machine being possible to process machining continuously for making an cutting edge of rotary bar and to revise easily machining program. This study aimed at the structural analysis of strength according to the configuration of new made 6-axis machine and at the machining accuracy and durability of rotary bar. As a result of test, the runout of new rotary bar manufactured out of 6-axis machine was decreased from 0.385 mm to 0.027mm extensively than old one. And good cutting ability and durability was obtained equal quality compared with imported products.

• Tribology and Lubricants
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• 제12권2호
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• pp.65-73
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• 1996

Rapid increase of Refrigeration and Air conditioning system in modem industries brings attention to the urgency of core technology development in the area. This paper presents theoretical investigation of the lubrication characteristics of rotary compressor for refrigeration and air conditioning. In order to analyze the lubrication characteristics of the main & sub bearing of rotary compressor, the bearing force and locus of shaft center are analyzed by the dynamic analysis of rotary compressor and numerical analysis of Reynolds equation as the operating condition is changed in various ways. In this paper, we used the Runge-Kutta method for the dynamic analysis of rotary compressor and the SOR (Successive OverRelaxation) method for the numerical analysis of Reynolds equation. The result shows that the operating condition of sub bearing is severer than that of main bearing, and eccentricity ratio grows as the bearing force increases. It is believed that the result can be applied to the design of alternative refrigerant rotary compressor.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1997년도 춘계학술대회논문집; 경주코오롱호텔; 22-23 May 1997
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• pp.260-265
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• 1997

Large dynamic loads act on the rotor in rotary compressors. There are unbalance forces due to eccentric rotation parts and gas forces induced by the difference in pressure between compression and suction gases6 Rotor-journal bearing system is nonlinear since the stiffness and damping coefficients of the lubricating oil film are not constant in the bearings. In this paper, the program for predicting the behaviors of rotor-journal bearing system of rotary compressor is developed. Finite element modeling is used to analyze the flexible rotor. The numerical results are compared with experimental results. The location of balancer weight are suggested for reducing rotor whiring displacement.