• 대한기계학회논문집A
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• 제20권6호
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• pp.1762-1772
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• 1996

The main objective of this study is to develop a gripper mechanixm that can be employed for assembly and removal tasks of a nozzle-dam of steam genetator in the process of the nuclear reactor maintenances. Brief description of the open-close thpe gripper mechanism, its position analysis, and its kinematic analysis are given. The optimal design of the gripper mechanism with and without slipping on its two gipping surfaces is considered. As an optimal design index, the ratio of the actuator force of prismatic cylinder to gripping load is proposed. Then, based on this index the oiptimal design is carried out to identify values of optimal design parameters for the gripper dechanism.

• 한국주거학회논문집
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• 제14권3호
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• pp.127-136
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• 2003

The purpose of this study is to establish concept about a plan direction of preschooler's library, and provide a design type of preschooler's library. As a result, the following findings were obtained: 1) For the preschooler's reading area, it should be segregated between schooler and preschooler. Because there is a difference between a library use action and a development characteristic, it needs to be segregated to avoid conflict using library for both of those groups. 2) The space composition of preschooler's library stands up, and of a tube considers a traffic line of a user according to the function and systematizes a child, and to cause an interest of preschoolers. 3) Furnitures and equipment of preschooler's library must arrange in consideration of human body size of a user in a tube.

• Nuclear Engineering and Technology
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• 제31권6호
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• pp.595-607
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• 1999

The reaction cross-sections of $^{nat}$Ti(p,X)$^{48}$ V, $^{nat}$Fe(p,X)$^{56}$ Co, $^{nat}$Cu(p,X)$^{65}$ Zn and $^{nat}$Mo(p,X)$^{96}$ Tc for TLA application are calculated in the frame of the ECIS-GNASH code system up to 60 MeV. The calculated results are compared with the experimental data taken from the EXFOR at the NEA Data Bank. A preliminary calculation with the global optical parameters of Varner et al. shows considerable differences from the experimental data at low energy range. The global optical parameters for the imaginary volume potential and the diffuseness of the imaginary potential are adjusted to achieve a better description of the experimental data in the vicinities of peak position below 16 MeV. 16 MeV.

• Animal Systematics, Evolution and Diversity
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• nspc9호
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• pp.18-29
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• 2016

An anisogammarid amphipod, Eogammarus possjeticus (Tzvetkova, 1967), is newly recorded from Jindo Island, Korea, with a detailed description and illustrations. The species belonging to the genus Eogammarus are sharing several plesiomorphic characteristics, so they are similar to each other. However, Eogammarus possjeticus can be discriminated from congeners by the following characters combined: appendages are not fossorial, setations of antennae are weak, and the number and position of robust setae on pleonal epimera, urosomes, and telson are different from its congeners. This is the first record of the genus Eogammarus Birstein, 1933 from Korean waters.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.93-97
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• 2005

This paper proposes a design of stepper motor control in microstep driven mode using FPGA (Field Programmable Gate Array) for hardware implementation. The methods to drive stepper motor in microstep excitation mode are to control of the controlling currents in each phase windings of stepper motor with reference signals. These reference signals are used for controlling the current levels, the required variation of current levels with rotor position can be obtained from the ideal linear or sinusoidal approximations to the static torque-displacement ($T-{\theta}$) characteristic curve. In addition, the hardware implementation of stepper motor controller can be designed uses VHDL (Very high speed integrated circuits Hardware Description Language) and synthesis using an Altera FPGA, FLEX10K family, EPF10K20RC240-4 device as target technology and use MAX+PlusII program for overall development. A multi-stack variable-reluctance stepper motor of Sanyo Denki is used in the experiments.

• 한국어류학회지
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• 제17권3호
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• pp.217-220
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• 2005

2004년 8월 제주도 남부연안에서 집어등에 의한 연안 자치어 조사과정 중에 당멸치과 (당멸치목)에 속하는 엽상자어 3개체 (표준체장 33.4~35.2 mm)를 채집하였다. 이들 엽상자어는 꼬리지느러미가 이차하고, 뒷지느러미가 작으며, 그 기점이 등지느러미 후단부 하방에 위치하는 점에서 '당멸치 Elops hawaiensis'로 동정되었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.11-14
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• 2001

In all Rapid Prototyping(RP) processes, computer-aided design(CAD) solid model is sliced into thin layers of uniform, but not necessarily constant, thickness in the building direction. Each cross-sectional layer is successively deposited and, at the same time, bonded onto the previous layer, the stacked layers form a physical part of the model. The objective of this study is to develop a method for obtaining necessary coordinates$(x,\;y,\;\theta_x,\;\theta_y)$ to position linear hotwire of the cutting system in three-dimensional space for the Variable Lamination Manufacturing process (VLM-S), which utilizes expandable polystyrene foam sheet as part material. In order to examine the applicability of the developed method to VLM-S, various three-dimensional shapes, such as a spanner, a patterned columm, and a pyramid were made using data obtained from the method.

• 한국소음진동공학회논문집
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• 제12권1호
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• pp.12-20
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• 2002

To control the noise of an enclosed sound field, we built a state space model using the acoustic modal parameter description. Using the state space model, we can investigate the controllability and observability, and find an appropriate position of control speaker and microphone to control sound field of the enclosed space. We implemented LQR(linear quadratic regulator) controller and reduced order observer to reduce the first acoustic mode. Experiments showed satisfactory results of 4∼10 dB reduction of magnitude of the first acoustic mode, and support the feasibility of the proposed scheme to lightly damped acoustic field.

• 아동학회지
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• 제22권2호
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• pp.205-218
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• 2001

This study explored the conception of children as portrayed in a personal diary written the middle period of the Chosun Dynasty. The Yangalok is a daily record in which Moonkun Lee wrote how he brought up his grandson. The Yangalok is an important historical document, showing how people brought up their children and indicating their conception of childhood. Research questions included the definition of the period of childhood and a description of parent-child relationships. It was found that childhood was completed by age sixteen, the importance of the child as family member hinged on his position as an heir, and the parent-child relationship was defined by Chin(親), including qualities of both love and discipline.

• 대한기계학회논문집
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• 제18권10호
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• pp.2501-2513
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• 1994

In this paper, a compact, light-weight, universal, spherical 3-degree-of-freedom, parallel-structured manual controller with high reflecting-force capability is implemented. First, the position analysis, kinematic modeling and analysis, force reflecting transformation, and applied force control schemes for a parallel structured 3 degree-of-freedom spherical system have been described. Then, a brief description of the system integration, its actual implementation hardware, and its preliminary analysis results are presented. The implemented parallel 3 degree-of-freedom spherical module is equipped with high gear-ratio reducers, and the friction due to the reducers is minimized by employing a force control algorithm, which results in a "power steering" effect for enhanced smoothness and transparency (for compactness and reduced weight).d weight).