• 한국공작기계학회논문집
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• 제16권4호
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• pp.71-78
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• 2007

Input shaping is known to be a very effective tool for suppressing residual vibration without introducing any complicated sensors and feedback control. Real-time input shaping schemes necessitate a process such that the input command is discretized to deal with non-prescribed, real-time input. Thus parameters associated with input command discretization, such as time spacing and duration time, are unknowns which affect the performance of input shaping schemes, especially for small and fast XY stages. This paper investigates the effects of input command discretization parameters, such as time spacing and duration time, on the dynamic performance of XY stages subjected to real-time input shaping. An experimental system is developed which is equipped with an XY stage driven by servo-motors and real-time user command. Experiments are performed to investigate the dynamic performance of XY stage by changing these parameters and to yield a strategy to gain better performance.

• 센서학회지
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• 제27권1호
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• pp.31-35
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• 2018

This paper describes a low-power, SNDR (signal-to-noise and distortion ration) enhanced SAR (successive approximation register) type 12b ADC (analog-to-digital converter) with noise shaping technique. For low power consumption and small chip size of the DAC (digital-to-analog converter), the top plate sampling technique and the dummy capacitor switching technique are used to implement 12b operation with a 10b capacitor array in DAC. Noise shaping technique is applied to improve the SNDR by reducing the errors from the mismatching of DAC capacitor arrays, the errors caused by attenuation capacitor and the errors from the comparator noise. The proposed SAR ADC is designed with a $0.18{\mu}m$ CMOS process. The simulation results show that the SNDR of the SAR ADC without the noise shaping technique is 71 dB and that of the SAR ADC with the noise shaping technique is 84 dB. We can achieve the 13 dB improvement in SNDR with this noise shaping technique. The power consumption is $73.8{\mu}W$ and the FoM (figure-of-merit) is 5.2fJ/conversion-step.

• 한국조경학회지
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• 제21권2호
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• pp.17-33
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• 1993

This paper is the on-site case study of the shaping of townscape of port towns in Korea. Inchon has been experienced the rapid urbanization after the opening of a port. Inchon is selected because of the relatively rapid process, the apparent event and influence, and the enough referneces of data about the landscape formation and transformation. As the value of historical landscape, it is very significant to study Inchon and the causes of change in townscape depend on the external element-the opening of a port, Japan colonial policy, economic progress, nationwide development. The main purpose of this study is scrutinized the process, the cause and effect, and the contents and the form of shaping of townscape. The result of the interpretation of landscape is never perfect but only a starting point. Finally this study will be applied to the pragmatic task as a basic tool which construct the desirable image of the city.

• 한국정밀공학회지
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• 제17권10호
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• pp.56-62
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• 2000

A fast and precise technique to make 3-dimensional object which is called direct metal shaping process is processed. It is very useful technique in design and inspection. Using this developed system, a solid object is made. In experiment, test parts are built by varying three factors, laser power, scan path, scan speed. This process used device, which is different from the widely used in rapid prototyping in that powder feeding device is used. Spraying powder directly at the focused laser beam and then three dimensional object is made by the deposit of melted metal powder. The optimum scanning path is found to be zigzag path, which had little thermal affection on base metal. As a result of these experiments, it was found that optimum scanning speed is 15mm/sec laser power is 50W. This constructed 3-dimensional object could be used in mold manufacturing directly.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.55-59
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• 2004

Recently, life cycle and lead-time of products have been shortened with the demand of customers. Therefore, it is important to reduce time and cost at the step of manufacturing trial molds. In order to realize three dimensional shape on CAD, the machining process has been widely used because it offers practical advantages such as precision and versatility. However, traditional machining process spends a lot of time in cutting product and the remained material causes trouble such as inconvenience for clean. In this work, a new machining process using the hot tool has been proposed to overcome those limitations. In the process, the hot tool moves the predetermined path and the heat of the tool decomposes the remained material. In order to set up the process, the hot tool to satisfy requirements is designed and the material thermal properties are obtained using the DSC and TGA machine. The relationships between process parameters and thermal radius of the tool are obtained through experiment.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 II
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• pp.887-890
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• 2003

High Speed data transmission over a long length of cable is limited due to the limited bandwidth of a cable which introduces ISI(Inter Symbol Interference). In order to compensate for the loss and phase dispersion in the cable, a pulse shaping in a transmitter and a line equalizer in receiver can be used. This paper presents a low-power and small-ana analog adaptive pulse shaping circuit and line equalizer, The design was fabricated in a 0.25${\mu}{\textrm}{m}$ mixed-signal CMOS process. The proposed pulse shaping circuit and equalizer operate at 400Mb/s on 50m STP(Shielded Twisted Pair) cable. It consumes 28.5${\mu}{\textrm}{m}$ with a 2.5-V power supply and occupies only 0.098 $\textrm{mm}^2$.

• 반도체디스플레이기술학회지
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• 제11권2호
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• pp.33-38
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• 2012

The wafer positioning robot in the semiconductor industry is required to operate at high speed for the improvement of productivity. The residual vibration caused by the high speed of the wafer positioning robot, however, makes the life of the robot shorter and the cycle time longer. In this study, the input shaping and the path of the system are designed for the reduction of the residual vibration and the improvement of the cycle time. The followings are the process for the reduction and the improvement; 1) System modeling of the wafer positioning robot, 2) Verification of dynamic characteristics of the wafer positioning robot, 3) Input shaping plan using impulse response reiteration, 4) Simulation test using SIMULINK program, 5) Analysis of result.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.559-563
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• 2005

The wafer positioning robot used in the semiconductor industry is required to operate at high speed for the improvement of productivity. However, the residual vibration produced by the high speed of the wafer positioning robot makes the life of the robot shorter and the cycle time longer. In this study, the input shaping and the path of the system are designed for the reduction of the residual vibration and the optimization of the cycle time. The followings are the process for the reduction and the optimization; 1)System modeling of wafer positioning robot, 2)Verification of dynamic characteristic of wafer positioning robot, 3)Input shaping plan using impulse response reiteration, 4)Simulation test using simulink, 6)Analysis of result.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 추계학술대회논문집
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• pp.342-345
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• 2004

A combination of deep drawing and cold forging process is tried to achieve near net shaping of automatic transmission part which has drum shape and thickness variation. It is key for successful shaping of the part to find out proper condition to combine two different forming methods. Finite element analysis can be utilized for that purpose effectively. Integrity, reliability, and durability of the part are improved by eliminating machining process. The developed process is applied in real manufacturing process successfully.

• 감성과학
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• 제12권1호
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• pp.97-108
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• 2009

제품 디자인에 있어서 조형화 과정은 실체적인 존재를 만들어 내는 과정이며, 최종적으로 제품에 대한 결과를 이끌어 내는 중요한 과정이다. 이러한 조형화 과정은 일반적으로 디자이너의 주도적인 작업에 의해서 이루어지고 있으며, 이 때 다양한 조형 요소들을 활용하여 결과물을 만들어 낸다. 본 연구에서는 제품 디자인 프로세스에 있어서 제품 형태의 조형화 과정에서 다루어지는 요소들이 소비자와 디자이너의 시각 차이에 의해서 생기는 차이에 대해 알아보고 소비자가 제품의 조형화 과정에 직접적인참여를 하는 방법과 소비자의 요구가 보다 효율적으로 조형화 과정에 반영되는 디자인 가이드라인의 제시에 대한 가능성을 고찰하고자 하였다. 이를 위하여 먼저 제품 형태를 구성하는 요소들에 대한 정립을 선행하여 기본적인 제품 조형 구성 체계를 마련하였다. 이를 기반으로 기본적인 제품 조형요소와 제품 조형원리를 일부 설정하여 소비자를 대상으로 55개의 컨셉 제품과 64개의 스피커 제품의 이미지에 대한 반응 실험을 진행하였다. 또한 일부 실험 자극물을 이용하여 디자이너들을 대상으로 동일한 실험을 진행하였는데, 실험 결과 소비자와 디자이너는 형태의 조형 요소에 대해 어느 정도 시각 차이를 보이며 이는 디자이너의 경우 주관적인 디자인 통념에 의해서, 소비자의 경우 제품에 대한 미숙한 시각적 이해에 의해서 차이가 생기는 것으로 나타났다. 이 결과를 바탕으로 디자이너는 소비자의 최종적인 감성반응을 이끌어내는 디자인 과정에 있어서 형태에 대한 시각 차이를 이해하고, 형태 조형원리를 기반으로 하는 조형요소의 구성을 활용 할 수 있다고 본다.