• JOURNAL OF ELECTRICAL WORLD
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• s.284
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• pp.60-65
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• 2000

가전제품은 최근 수년 사이에 급격한 사회정세의 변화와 더불어 소비자의식에 대폭적인 변혁을 가져온 가운데 적절한 가격의 납득이 가는 진짜상품이 요구되는 추세이다. 한편 가전제품에서의 센서(Sensor)기술은, 참으로 성능쇄신의 요소기술을 담당하는 중요한 기술로 센서 그 자체의 고도화$\cdot$다양화에 더하여 마이크로 프로세서를 주체로 하는 지적인 신호처리에 의한 기능과 성능의 향상이 눈부신 바 있으며, 이 두 수레바퀴에 의하여 가전제품용 센서의 인텔리전트시스템이 구성되고 있다. 본고에서는 후자의 신호처리에 의한 인텔리전트화 기술을 지적제어 처리로 간주하여, 센싱 기술에서의 지적제어처리의 자리매김과 구체적인 가전품에서의 응용 예로서 세탁기에 지적제어처리를 탑재하여 기능 향상을 도모한 개발사례를 중심으로 그 개요를 소개한다. 최근의 개발사례로서 세탁기, 에어컨, 냉장고, 청소기 등에 퍼지제어나 뉴럴네트워크, 또한 비선형 처리 등의 응용 예를 표로서 나타내었다. 특히 세탁기에서는 모터의 회전수를 검출하는 회전센서출력의 처리에 의해 다음의 두가지 센싱시스템을 개발하였다. (1) 부하량 검지 시스템 무단계 부하량 검출을 실현하여 검출오차를 약 1/3로 저감시킴과 동시에 에너지 절약(물$\cdot$세제$\cdot$시간)을 도모한다. (2) 언밸런스 건지 시스템 속도감속 성분량 추출에 의한 검출정도 향상과 현행센서 삭제에 의한 코스트 저감을 이룬다.

• Journal of the Korean Society of Industry Convergence
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• v.4 no.4
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• pp.379-386
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• 2001

The lower toughness or brittle materials for mechanical test lead to the additional requirement that applied displacements be controlled with high resolution. Biaxial tension and shear tester using stepper motor with harmonic driver is shown. The device had to be high resolution so that the crack initiation process of slow extension and steady growth could be examined, Grip plates were connected to a linear bearing and actuator. The actuators consisted of stepper motors with harmonic driver connected to pre-loaded ball screw and nut assemblies. The encoders and motor controllers were connected to a personal computer so that arbitrary displacements histories could he prescribed in normal and tangential directions. The linear bearings were used to react loads perpendicular to their axes while allowing low friction, parallel movement of the attached grips. Load cells measured the reactions normal and tangential. the loads measured the reactions were recorded by the computer.

• Journal of Bio-Environment Control
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• v.12 no.2
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• pp.57-62
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• 2003

In this study, a robotic manipulator for harvesting cucumber was developed. The objective of this research was to design and to construct a robotic manipulator specifically tailored to harvest cucumber in the greenhouse. The system was consisted of an integrated end-efffctor, an image processing system and a controlling system. Especially, the image processing system detected the quality of cucumber within each plant in order for the computer to furnish harvest instructions to the manipulator. In all tests of cucumber, the success rate for cucumber harvest was 84％ in the greenhouse. End-effector, image processing system and controlling system showed good performance. Based on the results of this research the following recommendations are made for further study. Besides harvesting cucumbers, the oldest leaves, creepers and the youngest small side leaves need to be removed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.5
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• pp.503-515
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• 2011

We developed a walking-assistance robot for walking rehabilitation and assessed the kinematic characteristics of a prototype. The walking-assistance robot is composed of hip, knee, and ankle joints, and each joint is driven by a motor with a decelerator. The equations of angular displacement while walking were derived by theoretically analyzing human locomotion, and the calculated angular displacements were then applied to the robot controller. The output angular displacement of each joint was measured and compared with its input angular displacement in walking experiments on a treadmill at various walking speeds and strides. The differences between the input and output angular displacements are 5.22% for the hip and 2.97% for the knee joints, and it has been confirmed that the walking-assistance robot works well.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.3
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• pp.1241-1246
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• 2014

Take-out robots used for handling of the plastic parts manufactured with the injection mold are usually the gantry type that consists of long and thin links. In this study, we want to evaluate the safety of the take-out Robot structure through finite element analysis. The take-out Robot is automated robot to transport from one location to another in the molded article. The take-out Robot structure has a 380 kilogram weight, a 1300mm width, a 670.5mm depth and a 670mm height. It confirms the equivalent stress and the deformation of the load and its own weight through weight analysis. It looks for the natural frequency of the take-out robot through modal analysis. It confirms the acceleration, the normal stress and the deformation about the natural frequency of the take-out robot through response analysis. Also It repeats the analysis by changing the structure of the take-out robot, to confirm the results and it is determined whether the safety of the structure. These analysis results are effectively used to reduce the vibration of the take-out robot.

• Journal of the Korean Society for Heat Treatment
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• v.36 no.5
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• pp.311-317
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• 2023

An autofilter is a device that removes impurities contained in heavy fuel oil used in diesel engines of ships or power plants, and also automatically removes impurities accumulated in the filter through a reverse washing function. The reducer-integrated motor serves to rotate the filter at low speed to enable reverse automatic cleaning in the autofilter device. To achieve a low speed of 0.65 to 0.75 rpm in a reducer-integrated motor, a small motor that can operate at 97rpm at a rated voltage of 110 V and 112.5 rpm at 220 V is required. Additionally, a large gear ratio of 1/150 is required. To ensure the durability and reliability of these reducers, the strength of the gear must be evaluated at the design stage. In general, there is a limit to evaluating the stress and strain state according to the vibration characteristics acting on each gear in the driving state of the reducer through quasi-static analysis. Therefore, in this study, the operation characteristics of the auto filter's reducer-integrated motor were first analyzed using the rigid body dynamics analysis method. Then, this rigid body dynamics analysis model was extended to a flexible multibody dynamics analysis model to analyze the stress and strain states acting on each gear and evaluate the design feasibility of the gear.

• Journal of Aerospace System Engineering
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• v.17 no.6
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• pp.27-34
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• 2023

This paper presents the application of a magnetic gear to the electric propulsion system for an aircraft. Since high torque is required in aircraft electric propulsion systems, combining a speed reducer can amplify the torque. However, mechanical gears have issues, such as friction, vibration, and heat generation, which lead to maintenance challenges. In the case of a direct-drive motor that does not use mechanical gears, the size and weight of the motor increase to achieve high torque. This paper proposes the application of a magnetic gear to solve the maintenance issues of mechanical gears and the weight increase problem of direct-drive motors in aircraft electric propulsion systems. In this paper, a magnetic gear suitable for aircraft electric propulsion systems is designed, and it is compared with a direct-drive motor in terms of performance and the feasibility of applying the magnetic gear is verified.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.102-102
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• 2017

제주산 감귤생산량은 51만톤(2016년)으로 수확기에 장마 등과 같은 환경적 요인에 의해 결점과의 비율이 24.9% 정도이다. 결점과로 통칭되는 비상품과는 일부 대기업의 쥬스공장에서 수매하는 량을 제외한 대부분은 자체 농장에서 폐기처분되고 있어 많은 감귤 비상품과 처리에 많은 문제점이 노출되어 오고있다. 성주군에서는 결점과 및 비상품과가 시장에 출하되는 것을 방지하기 위하여 자체 수매하여 액비, 발효퇴비, 사료화 가공 등에 많은 비용을 투자하고 있다. 따라서 본 연구는 당도가 15 Brix에 달하는 고당도 감귤 및 참외의 비상품과를 효과적으로 착즙하여 감귤 착즙액은 생산농자재로 환원하고, 참외 착즙액은 참외조청용 원료로 사용하는 기술을 개발하고자 한다. 착즙장치는 PLATE형 스크류, 테퍼 스크류 하우징, 파쇄된 과즙을 마지막 단계인 압입하는 고깔부 및 동력을 공급하는 구동부로 구성하였다. 개발한 고액분리 착즙장치의 외형은 $W1,000{\times}L2,000{\times}H1,070$이고 사용동력은 0,75kw, 1/30 감속모터를 사용하였다. 일반적인 착즙장치는 1단 분쇄와 동일 원통형의 스크류 압착으로 고액분리를 위한 착즙이 이루어지기 때문에 처리량이 150kg/hr에 불과하지만 개발한 고액분리장치는 2차 분쇄와 원통형과 원추형의 스크류 압착 후 고액분리망을 통과하도록 하여 500kg/hr 이상을 착즙이 가능하도록 개발하였다. 따라서 농산물의 고액분리를 통한 농산물의 가공을 위한 연속 착즙 장치는 2단 분쇄와 원통형 및 원추형 압착 미세망을 이용한 고액분리 착즙기는 기존 착즙기에 비하여 처리량이 3배 이상 증가되었다는 것을 알 수 있었다. 기존 감귤 착즙기의 수율은 60%정도이나 개발 착즙기의 착즙 수율은 66.5%로 나타나 본 연구에서 개발한 착즙기의 수율이 기존 착즙기의 수율보다 약간 높게 나타났다. 기존 착즙기는 원료(농산물의 종류)의 종류나 전처리에 제한이 있어 전용으로 사용하는데 비해 본 연구에서 개발한 고액분리 착즙기는 원료의 종류나 전처리 상태에 관계없이 사용 가능함을 확인하였다.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.7 no.2
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• pp.52-59
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• 2008

The objective of this study is to develop an automatic object changer unit to improve processing problems existed in the conventional horizontal machining center. To achieve this goal, this study designed a horizontal transfer as the second project continued to the first project that designed a upward and downward traverse unit. A horizontal traverse unit shows a symmetric structure and consists of frame, which consists of four unit tools, motor and reducer, which are fixed at a frame, operation unit with pinions, first traverse unit, and second traverse unit. Constraint conditions based on the operation mechanism with these elements were configured and obtained following results after modeling a model for a traverse motor. In the kinematic expression of sliding motion with one degree of freedom, the sliding motion is constrained. Also, the rack 3 installed at a frame is used to configure possible kinematic constraint conditions of the rack 2 according to the rolling motion of the pinion 2 in the first traverse unit. In addition, the moment of inertia that is a type of kinetic energy in a converted horizontal traverse unit in the side of the reducer can be applied to introduce the moment of inertia of a converted horizontal traverse unit in the side of the reducer by using the sum of kinetic energy in the rack and pinion, which is a part of the horizontal traverse unit. Also, the equation of motion of the converted upward and downward traverse unit in the side of the motor using the equation of motion of the motor. Furthermore, the horizontal traverse unit predetermines the mass of the first and second traverse unit and applied load including the radius and reduction ratio of the pitch circle in the pinion 1 and applied load to the rack 2. Then, a proper motor can be determined using several parameters in the upward and downward traverse unit in order to verify such predetermined specifications. In future studies later this study, a simulation that verifies the results of the previous two stages of studies using a finite element method.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.10
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• pp.60-65
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• 2003

An experimental study was performed to understand ignition characteristics of gas turbine combustor with rotating fuel injection system. Liquid fuel applied to the inner surface of rotating fuel nozzle which was driven by high speed electrical motor is flung away by centrifugal forces. The real scale combustor and test rig was manufactured and tested under atmospheric condition in KARl combustion test facility. From the test results, this combustor ignition characteristics are highly dependent upon fuel nozzle rotating speed. Futhermore, combustor exit gas temperature was rapidly changed by increasing or decreasing the fuel nozzle rotating speed.