• Journal of Electrical Engineering and Technology
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• 제12권4호
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• pp.1627-1633
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• 2017

This paper proposes a voice enhancing ear-protection system which is based on feedback active noise control(FBANC). The proposed system selectively suppresses the background noise and preserves the talking voice by controlling the adaptive algorithm with the voice activity period detection module. The noise reduction performance of the proposed noise canceling algorithm is analytically derived for the two key performance affecting parameters, i.e., electro-acoustic coupling distance and noise bandwidth. The proposed system is also implemented with a floating-point DSP system and its performance is experimentally tested to compare with the analytically derived results. The achieved levels of noise reduction for the three different noise bandwidths cases, i.e., 10Hz, 50Hz, and 90Hz, are high to show 17.05dB, 10.54dB and 8.99dB, respectively. The feasibility of the proposed system is also shown by the peak noise reduction achieved more than 25dB while preserving the voice component in the frequency range between 200-800Hz.

• 한국농공학회지
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• 제36권4호
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• pp.33-38
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• 1994

Floating-type automatic turnout was developed for the purpose of reducing labor cost and labor-working hours related to turnout management. The point of automation is to use a flexible-float within the turnout. The weight of float is changed by emptying and filling with water at the beginning and ending of irrigation. The turnout is controlled to open and close small bole on the float bottom using electromagnets. With the weight control of float. the gate of turnout is opened by the empty float to begin irrigatiom and is closed by the filled float to stop irrigation. The turnout was designed to be operated by the main computer and to minimize electric power consumption by sending an electric current at the beginning and ending of irrigation. The functional experiment was succesfully carried out and the rating curves for both free overflow condition and submerged flow condition were derived.

• 한국위성정보통신학회논문지
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• 제10권2호
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• pp.115-120
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• 2015

지금까지 저궤도 위성의 자세제어 SW는 자세제어 연산을 위해서 CPU Resource로 있는 FPU를 사용하였으며, 이 결과 SW Throughput의 상당 부분이 행렬 곱셈 연산에 사용 되었다. 향후 위성에서 제어 주기가 더 짧아지고, 연산 량이 증가하면, 심각한 영향을 받을 수 있기 때문에 곱셈 전용 HW구현이 필요하게 되었다. 본 논문에서는 부동소수점 행렬 곱셈을 전용으로 수행하는 HW를 구현 및 성능 측정을 수행한 결과를 제시하며 추가적인 성능 향상을 위한 방법들과 향후 과제를 언급한다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 전력전자학술대회 논문집(2)
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• pp.575-578
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• 2004

The performance of an active power filter(APF) depends on the inverter characteristic, the control method, and the accuracy of reference signal generator. The accuracy of reference generator is the most critical item to determine the performance of active power filter. This paper introduces a novel reference signal generator composed of improved adaptive predictive filter. The performance of proposed reference signal generator was first verified through a simulation with MATLAB. Furthermore, the application of feasibility was evaluated through experimenting with a single-phase APF prototype based on the proposed reference generator, which was implemented using the TMS320C31 floating-point signal processor. Both simulations and experimental results confirm that our reference signal generator can be used successfully in practical active power filters.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• 제5B권1호
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• pp.50-56
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• 2005

This paper develops a sensorless BLDCM drive for frequently startup. The position information is based on detecting the zero-crossing point of the BEMF that can be directly obtained from the terminal voltage of the floating phase without voltage-dividing and filtering. As a result, this approach makes it possible to detect the rotor position over a wide speed range, especially at a lower speed. A fast startup procedure is also discussed because the induced BEMF signals are not present when motor is at rest. Experimental results shows that the schemes implemented are feasible and the performance achieved are satisfactory.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2006년도 추계학술대회 발표 논문집
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• pp.43-46
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• 2006

본 논문은 PCB(printed circuit board)에 납땜이 되어 장착된 부품들의 들뜸 상태 검사 알고리즘에 관한 연구이다. 전자산업의 발달로 제품이 소형화, SMD화, 고집적화가 함께 추구되고 있으며, 특히 리드(lead)의 fine-pitch화 현상으로 인해 부품의 들뜸 상태 검사의 중요성은 매우 부각되고 있다. 따라서 본 논문에서는 2차원 포인터 레이저 거리센서를 이용하여 PCB위에 장착된 부품의 들뜸 상태를 검사하고자 한다. 이를 위해 레이저 측정용 장치를 제작하여 부품의 들뜸 검사 알고리즘의 유용성 및 들뜸의 상태 판단 여부를 확인하였다. 본 논문에서 사용한 기준 부품은 각칩 형태로 된 저항, 커패시터와 BGA 및 QFP이며 이 부품들을 이용하여 리드와 바디의 들뜸 상태를 검사하였다. 검사 기준으로 리드의 들뜸은 Scan Teaching 방식을 이용하였으며, 바디의 들뜸은 단차 Teaching 방식을 이용하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.1056-1059
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• 1996

In this paper, we analyzed the effect of the change of the rotor time constant on the performance of the indirect vector control system. By employing indirect field orientation technique, we have also suggested an optimal control algorithm that allows an induction motor to maintain the maximum torque under the changing environment of rotor time constant. A computer simulation on the transient response of the output torque was demonstrated. To verify the validity of the method that has been proposed in this paper, an experiment has been performed utilizing TMS32OC31(40MHz) DSP chip which is capable of performing floating-point arithmetic in real time.

• 한국디지털건축인테리어학회논문집
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• 제2권1호
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• pp.39-44
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• 2002

Purpose of this paper is to find the Baroquely characteristics in Korean Temple Architecture.(MA KOK-SA) We could find out the characteristics as follows; First, visual freedom and floating in the arrangement of the temple buildings through segmenting the axis. Second, tension of variations in size, distance, and frame. Third, diverse sceneries provided by Sequential(dynamic) view points. Fourth, visual process and sharp contrast between horizontality and verticality, and unexpected scenery, etc.

• 한국정보처리학회논문지
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• 제5권7호
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• pp.1883-1895
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• 1998

Java 프로그램밍 언어는 general-purpose concurrent object-oriented 언어로 알려져 있다. Java 언어는 개념과 구문 모두가 매우 간결하고 통일되어 있으며 인터넷 환경에서 최대한 활용되도록 하기 위하여 가상기계 개념을 도입하여 목적코드를 생성한다. 프로그래밍 언어에서 가장 중요한 부분이 data type 부분이다. Java 언어는 primitive type과 reference type을 지원한다. Primitive type과 reference type을 지원한다. Primitive type에는 boolean type integral type이 있다. Integral type에는 character, byte, short integer, integer, long integer, single-precision 과 double-precision floating point number가 있다. Reference type에는 class type, interface type, array type이 있다. 그러나 Java 언어는 general-purpose 프로그래밍 언어가 일반적으로 지원하는 structure type을 지원하지 않는다. 대신에 class type이 structure type을 포함하여 지원하는 구조로 되어 있다. 그러나 class type과 structure type은 서로 상이한 data type으로 판단된다. 따라서 Java 언어가 general-purpose의 성격을 가지기 위해서는 structure type을 명시적으로 지원하는 것이 바람직하다고 생각된다. 이 논문은 structure type을 Java 언어에 포함시킬 것을 제안한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 전문대학교육위원
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• pp.120-122
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• 2004

This paper describes the digital relay simulator by use of DSP for digital relay test. The simulator software has EMTP simulation data file conversion. user define simulation data generation. data analysis engine. etc. The simulator hardware design uses 32bit floating point DSP architecture to achivev flexibility and high speed operation.