• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 G
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• pp.3230-3232
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• 1999

In this paper describes the design and improvement of a hybrid module for dual slope A/D converter. Since the input voltage to be converted is very sensitive and small. A/D converter must have the temperature stability. low-drift, and the high-resolution the conversion. A dual slop A/D converter circuit which is controlled by microprocessoer has been developed to reduce the offset voltage and the drift characteristics of operation amplifiers, and to improve the A/D conversion speed. Also hybrid module has been adapted to obtain the to obtain the stable and accurate A/D conversion for low cost use. The evaluation of the designed hybrid module has been shown as having a good performance, which will give usefull application to the industrial measurements use.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 C
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• pp.1446-1448
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• 1997

TEC(Thermoelectric conversion) is direct conversion method between thermal energy and electric energy. We studied on the mechanical, electrical and thermal properties of thermoelectric module and made experimental thermoelectric generator with BiTe material.

• 한국정밀공학회지
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• 제25권4호
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• pp.77-85
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• 2008

PDF is widely accepted as a standard document format and now it supports 3D contents as well. Within the engineering application areas, this new 3D feature may be used to support sharing of 3D documents and thus collaboration between engineering departments, suppliers and partners. In this paper, we describe a system that automatically generates formatted engineering documents including 3D data converted from 3D applications such as commercial 3D CAD viewer. The system consists of two major modules. One is U3D conversion module and the other is PDF conversion module. U3D conversion module extracts geometry, view data, assembly and disassembly information from 3D viewer and converts to U3D format, currently in IDTF text file format. PDF conversion module generates a PDF file and inserts U3D data, various annotation information, and scripts for custom generated operations such as assembly and disassembly in the PDF document.

• 한국정밀공학회지
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• 제8권1호
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• pp.105-115
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• 1991

This paper describes an integrated CAD and CAPP system for prismatic parts of injection mold which generates a complete process plan automatically from CAD data of a part without human intervention. This system employs Auto CAD as a CAD model and GS-CAPP as an automatic process planning system for injection mold. The proposed CAD/CAPP system consists of three modules such as CAD data conversion module, manufacturing feature recognition module, and CAD/CAPP interface module. CAD data conversion module transforms design data of AutoCAD into three dimensional part data. Manufacturing feature recognition module extracts specific manufacturing features of a part using feature recognition rule base. Each feature can be recognized by combining geometry, position and size of the feature. CAD/CAPP interface module links manufacturing feature codes and other head data to automatic process planning system. The CAD/CAPP system can improve the efficiency of process planning activities and reduce the time required for process planning. This system can provide a basis for the development of part feature based design by analyzing manufacturing features.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2005년도 전력전자학술대회 논문집
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• pp.279-282
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• 2005

Recently, due to the launching of digital broadcasting service, a demand of PDP TV with large screen size is sharply rising. PDP power module is mainly divided into power factor correction (PFC) stage and sustaining power stage. Especially, sustaining power module has pulsating load characteristics. So, the hard switching at light load condition causes low efficiency and thermal problem. Therefore, a new power conversion circuit for sustaining power module of 60' PDP is proposed whose ZVS is obtained by additional ZVS tank. This paper presents properties of the proposed converter through mode analysis, numerical analysis. And a 900w prototype for sustaining power module of 60' PDP is produced to verify the analytic results. As an experimental results, ZVS is achieved from full load to 10% load variation and more than 92% of high efficiency is obtained at 10% load condition.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 전력전자학술대회 논문집(2)
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• pp.704-708
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• 2004

Recently, many nation have released standard such as IEC 61000-3-2 and IEEE 59, which impose a limit on the harmonic current drawn by equipment connected to AC line in order to prevent the distortion of an AC Line. Therefore, Plasma Display Panel (PDP) which is highlightened in digital display device also has the Power Factor Correction (PFC) circuit to meet the harmonic requirements. In PDP power module, the conventional boost converter is usually used for the PFC circuit. However, it comes serious thermal problem on it's bridge diode due to heat of PDP, and therefore the system stability is not guaranteed. In this paper, the bridgeless boost converter, which is used for PFC circuit of the PDP power module, is designed and verified the possibility of the application in a practical product in a view of efficiency, component count, temperature and etc.

• 전기의세계
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• 제30권10호
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• pp.655-661
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• 1981

The concentrating solar module with high concentration ratio(320)has been studied.in this paper. The solar module was composed of the EMVJ solar cell, (Fresnel Lens-DCPC)concentrator and heat sink, and was measured by using the PASTF system. The experimental result and the result analysis for the individual item of the module were as f ollows; (1) The conversion efficiency of the module was 8.3%. (2) The optical efficiency of the concentrator was 46.5% (DCPC; 84.8%, Fresnel Lens; 54.8%). (3) The thermal loss of the solar cell was 4.9%. And methods for the further improvement of the concentrating solar module efficiency have been suggested.

• 전자공학회논문지
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• 제52권2호
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• pp.50-54
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• 2015

본 논문에서는 밀리미터파 센서 응용을 위한 낮은 변환손실 및 높은 LO-RF 격리도 특성의 W-band MMIC 믹서 모듈을 설계 및 제작하였다. MMIC 믹서는 $0.1{\mu}m$ MHEMT를 이용하여 설계 및 제작되었다. MMIC 믹서는 낮은 변환손실과 높은 LO-RF 격리도 특성을 얻기 위해 RF 입력단에 MHEMT를 추가하여 설계하였다. 제작된 MMIC 칩을 모듈화 하기 위해 CPW-도파관 변환기를 설계 및 제작하였으며, 최종적으로 MMIC 믹서 모듈을 개발하였다. MMIC 믹서 모듈의 측정결과 변환손실 특성은 94 GHz에서 MMIC 칩은 6.3 dB, MMIC 모듈은 9.5 dB의 양호한 특성을 나타내었다. MMIC 믹서 모듈의 LO-RF 격리도는 94 GHz에서 30.4 dB의 양호한 측정 결과를 얻었다. 본 논문에서 개발된 W-band MMIC 믹서모듈은 기존의 발표된 W-band(75-110 GHz) MMIC 믹서와 비교하여 우수한 성능을 나타내었다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -2
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• pp.1133-1136
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• 2002

We designed and fabricated a low local oscillation (LO) power V-band CPW mixer module using a CPW-to-waveguide transition technology for the application of millimeter-wave wireless communication systems. The mixer was designed using a unique gate mixing architecture to achieve simultaneously a low LO input power, a high conversion gain, and good LO-RF isolation characteristics. The fabricated mixer exhibited a high conversion gain of 2 dB at a low LO power of 0 dBm. For data transmission of the 60 ㎓ wireless LNA systems, we fabricated a CPW-to-waveguide converter module of WR-15 type and mounted the fabricated mixer in the converter module. The fabricated V-band mixer exhibited a higher conversion gain and a lower LO input power than other reported V-band mixers.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.45-50
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• 2011

The efficiency of solar cell was about 4[%] in initial stage of photovoltaic industry, but it has quite a lot of efficiency through technology advances. Today, the efficiency of c-Si solar cells is about 17 to 19[%] and the efficiency of PV modules is about 14 to 15 [%]. We called that electrical losses occurred in the Conversion of solar cells to PV modules are CTM loss(Cell To Module loss), the CTM loss typically has a value of about3~5[%]. The more efficiency of solar cell increase, differences are larger because the efficiency decrease owing to physical or technical problems occurred in the Conversion of solar cells to PV modules. In this study, the power loss factors occurred in the Conversion of solar cells to PV modules are analyzed and it is proposed that how to reduce losses of the PV module. The types of power loss factor are (1)losses of front glass and encapsulant(generally EVA sheet), (2)losses by sorting miss, (3)losses by interconnection, (4)losses by the field aging of PV modules. In further study, experimental and evaluation will be conducted to make demonstrate for proposed solutions.