• Journal of electromagnetic engineering and science
• /
• 제10권3호
• /
• pp.138-145
• /
• 2010

In this paper, we report the test results of a small-scale prototype that implements an analogue-beam-formed phased antenna array in the E-band. A four-channel dual-conversion receive RF module for 71~76 GHz frequency band has been developed and integrated with a linear end-fire antenna array. Measured performance is very close to the simulated results. An ad-hoc wireless communication system has also been demonstrated. Low BER was measured for an 8PSK data stream at 1.5 Gbps with the receive array beam formed in the direction of arrival of the transmitted signal. To our knowledge this is the first steerable antenna array reported to date in the E-band.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2001년도 하계학술대회 논문집 B
• /
• pp.1284-1286
• /
• 2001

In this paper, the operating characteristics of a 3 kW class grid-interactive photovoltaic(PV) power system was analysed from January 1998 to December 2000. The construction of the PV system includes a DC/AC inverter for grid connection, PV module, and data Monitoring & Acquisition system. The major results of the field test of the 3 kW class grid-interactive PV system showed that the system utilization rate was 13.83% the conversion efficiency of the inverter was 88% at an over half load, and the PV system generated the electricity more then 300 kWh per month.

• 한국공작기계학회:학술대회논문집
• /
• 한국공작기계학회 1999년도 춘계학술대회 논문집
• /
• pp.69-74
• /
• 1999

This paper aims to DNC application of car seat cushion die. DNC systems are consist of CAD(CATIA1, CAM(Z-MASTER, OMEGA) software and CNC milling machine. CAM software is purpose to G-code generation for CNC programming. Then CAM software and CNC milling machine are connect to RS-232-C cable for networking.

• 제어로봇시스템학회논문지
• /
• 제12권9호
• /
• pp.912-917
• /
• 2006

A strain gauge weight measuring instrumentation system was designed with RF sensor network facilities. In the sensor module system data conversion and a series of signal processing were totally equipped. 16 strain gauges are incoming sensors and each output of the strain gauge was amplified and filtered for proper analog signal processing. Several measuring instrumentation OP amps and general purposed OP amps were used. 12 bits A/D converters converted analog signals to digital bits and a PIC microprocessor controlled the 16 channels of strain gauges. RF RS232 modules were used for wireless communication between the PIC microprocessor and an Ethernet host far a remote sensor monitoring system development.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
• /
• pp.1788-1790
• /
• 2005

In this paper, an operating characteristics of a 50 kW gird-connected photovoltaic(PV) power system was analysed from 2000 to 2004. The construction of the PV system includes a 3-phase inverter for grid connection, PV module, distribution box, and data monitoring system. The major results of the demonstration test of the 50 kW class gird-connected PV system showed that efficiency of PV system was 11.13%, and the conversion efficiency of the inverter was 92% at a 50% load.

• JSTS:Journal of Semiconductor Technology and Science
• /
• 제5권3호
• /
• pp.210-219
• /
• 2005

We report on a low-cost V-band wireless transceiver with no use of any local oscillator in the receiver block using a self-heterodyne architecture. V-band millimeter-wave monolithic IC (MMIC) modules were developed to demonstrate the wireless transceiver using coplanar waveguide (CPW) and GaAs PHEMT technologies. The MMIC modules such as the MMIC low noise amplifier (LNA), medium power amplifier (MPA) and the up/down-mixer were installed in the transceiver system. To interface the MMIC chips with the component modules for the transceiver system, CPW-to-waveguide fin-line transition modules of WR-15 type were designed and fabricated. The fabricated LNA modules showed a $S_{21}$ gain of 8.4 dB and a noise figure of 5.6 dB at 58 GHz. The MPA modules exhibited a gain of 6.9 dB and a $P_{1dB}$ of 5.4 dBm at 58 GHz. The conversion losses of the up-mixer and the down-mixer module were 14.3 dB at a LO power of 15 dBm, and 19.7 dB at a LO power of 0 dBm, respectively. From the measurement of V-band wireless transceiver, a conversion gain of 0.2 dB and a $P_{1dB}$ of 5.2 dBm were obtained in the transmitter block. The receiver block showed a conversion gain of 2.1 dB and a $P_{1dB}$ of -18.6 dBm. The wireless transceiver system demonstrated a successful data transfer within a distance of 5 meters.

• 대한전자공학회논문지TC
• /
• 제42권6호
• /
• pp.9-16
• /
• 2005

본 논문에서는 액세스 망 인터페이스로 EPON 정합을 기본으로 하는 홈 네트워크에서 방송 서비스와 IP 데이터 서비스를 융합하는 것에 초점을 두고자 한다. 본 논문에서는 액세스 망에서는 오버레이 전송 방법을 이용하고 홈 네트워크에서는 멀티캐스트 그룹 관리 프로토콜인 IGMP와 IGMP 스누핑 기능을 이용함으로써 액세스 망에서뿐만 아니라 댁내에서도 방송 서비스와 데이터 서비스를 융합시킬 수 있는 새로운 구조를 제안한다. 또한, 홈 게이트웨이를 통해 댁내 방송 서비스를 지원하기 위한 일련의 방법 및 절차에 대하여 설명한다. 본 논문에서 제안하고자 하는 방법은 다음의 3 가지로 구성되어 있다. I) 방송신호와 인터넷 데이터의 오버레이 전송 모델, ii) 다중 튜너 시스템을 이용하는 튜너/변화 모듈에서 특정 방송 채널을 선택하고 선택된 방송 스트림을 IP 멀티캐스트 패킷으로의 변환, iii) 변환된 IP 멀티캐스트 패킷을 L2 이더넷 홈 게이트웨이의 코어 모듈인 L2 이더넷 스위치로 보내고 IGMP 스누핑 기능을 이용하여 L2 멀티캐스트 처리 방법에 의하여 목적지 포트로의 전송.

• Spatial Information Research
• /
• 제22권2호
• /
• pp.31-44
• /
• 2014

응용프로그램은 그 목적에 따라 최적의 데이터 모델을 활용하며, 이러한 응용프로그램을 위한 3차원 모델링 데이터는 선택된 데이터 모델을 기반으로 생성된다. 이러한 이유로, 동일한 공간의 지형지물을 표현하기 위해 다양한 데이터 셋이 존재한다. 그러한 중복된 데이터 셋은 공간정보 산업의 재정적 측면에서 문제를 가져올 뿐만 아니라, 시스템호환성과 데이터 비교가능성에서도 심각한 문제를 야기한다. 이러한 문제를 극복하기 위하여, 본 연구에서는 항목클래스내의 공간객체들 간의 위상적 관계를 이용하여 TRM (Topological Relation Method)이라고 하는 공간데이터융합 방법을 제안한다. TRM은 응용프로그램 수준에서 구현되는 공간데이터 융합방법으로써, 서로 다른 데이터 모델에 의해 생성된 기하데이터들을 응용시스템에서 어떠한 데이터 변환이나 교환 과정을 거치지 않고, 직접적으로 실내공간 위치기반 서비스에 제공하기 위해 사용된다. 이러한 위상관계는 IndoorGML의 기본 개념으로 정의 및 기술된다. TRM의 개념을 기술한 후, 3D GIS상에서 제안된 데이터 융합방법의 실험적 구현을 보여준다. 마지막으로서 본 연구의 한계와 향후 연구에 대해 정리한다.

• International Journal of Precision Engineering and Manufacturing
• /
• 제2권2호
• /
• pp.38-47
• /
• 2001

This paper decribes the development of computer-aided design of a very precise progressice die for lead frame of semiconductor chip. The approach to the system is based on knowledgr-based rules. Knowledge of fie이 experts. This system has been written in AutoLISP using AutoCAD ona personal computer and the I-DEAS drafting programming Language on the I-DEAS mater series drafting with on HP9000/715(64) workstation. Data exchange between AutoCAD and I-DEAS master series drafting is accomplished using DXF(drawing exchange format) and IGES(initial graphics exchange specification) files. This system is composed of six main modules, which are input and shape treatment, production feasibility check, strip layout, data conversion, die layout, and post processing modules. Based on Knowledge-based rules, the system considers several factors, such as V-notches, dimple, pad chamfer, spank, cavity punch, camber, coined area, cross bow, material and thickness of product, complexities of blank geometry and punch profiles, specifications of available presses, and the availability of standard parts. As forming processes and the die design system using 2D geometry recognition are integrated with the technology of process planning, die design, and CAE analysis, the standardization of die part for lead frames requiting a high precision process is possible. The die layout drawing generated by the die layout module s displayed in graphic form. The developed system makes it possible to design and manufacture lead frame of a semiconductor more efficiently.

• 한국태양에너지학회 논문집
• /
• 제38권3호
• /
• pp.1-20
• /
• 2018

It is a very important and fundamental process to know accurately the intensity of the solar energy coming into the installed module considering the tilted angle. Europe and the US commonly use a program called PVsyst to convert the global horizontal irradiation to global irradiation on tilted plane. There are two types of models that PVsyst uses to convert to irradiation on tilted plane. In this paper, Perez model, which is a decomposition model and Perez model, which is a transposition model used in PVsyst, are applied based on global horizontal irradiation and global irradiation on tilted plane measured in a specific area. The comparison of the decomposition model shows the effect of the transpostion model on global irradiation on tilted plane conversion by comparing the ratio of the horizontal diffuse irradiation amount of the Watanabe model which are highly trusted in Asia and the Perez model. The comparison of transposition model confirm the error between the measured data and the calculated value which is applied Perez model to global horizontal irradiation decomposed by Perez model and Watanabe model. Based on the two comparisons, This paper propose a method to confirm the reliability of transposition model and reduce the error when PVsyst is used in Korea.