• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.3
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• pp.473-479
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• 2015

Thermal relays are sometimes used instead of long time overcurrent relays for motor protection. But, it is difficult for any relay design engineer to adequately approximate motor heating curves which represent the average of a difficult-to-define thermal zone. Thermal relays frequently may not provide sufficient protection on heavy overloads. Digital multifunction relays are microprocessor-based devices. These relays offer highly reliable and advanced protection of motors. If a situation can be mathematically described, the microprocessor in a digital relay can be programmed to tackle that problem. Today's motor protection is accomplished with digital protective relays. Digital relays offer additional, highly important features to complement protection. The best way to prevent short in motor is to not overheat and degrade the insulation.

• Proceedings of the Korea Contents Association Conference
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• 2004.05a
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• pp.522-528
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• 2004

Mobile internet service based on CDMA network evolution and multifunction mobile terminal is popular in Korea. Mobile internet service is classified as the information service using browser and mobile multimedia service using download platform. Killer applications based on multifunction mobile terminals have been developed for new business in mobile internet services. One of killer applications is location based seurvice (LBS) using mobile location information. In this paper, we develop mobile map browser using WIPI platform that is the main function in LBS. Mobile map browser interworking with GIS server provides the map information. The developed mobile map browser can be working on PDA and telematics terminals when WIPI is porting on these devices.

• Korean Institute of Interior Design Journal
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• no.29
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• pp.181-187
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• 2001

The art museum plays a role as a cultural space that can solve the cultural desire of people and see a good art works. It is in exhibition space that they personally exchange the feeling between an art work and a viewer in art museum. The types and works - a fiber, a photo, an establishment that needs many places, devices, a video art, and an action art called "performance", cultural art - are shown in small art museum. Moreover, exhibition spaces are modified into the space of another art activities like dancing, music concerts in small art museum because it has no profit space for diverse art activities. And the exhibition the characters of the exhibition space in small art museum. So, it needs to change the characters of the exhibition space in small art museum. Under these background, this stud\ulcorner surveys and analyzes the exhibits, the organization methods, the modified conditions, and the scale of the existing exhibitional space in small art museum. Therefore, the goal of this study is to suggest the composition of the exhibition space unit considering the function and the multifunction in minimum art museum and small art museum.

• Journal of Electrical Engineering and Technology
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• v.11 no.1
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• pp.9-19
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• 2016

Accurate models of the characteristics of typical inverse-time overcurrent (OC) protective devices play an important role in the protective coordination schemes. This paper presents a novel approach to determine the OC protective device parameters. The approach is based on the Eigensystem Realization Algorithm which generates a state space model to fit the characteristics of OC protective devices. Instead of the conventional characteristic curves, the dynamic state space model gives a more exact fit of the OC protective device characteristics. This paper demonstrates the feasibility of decomposing the characteristic curve into smooth components and oscillation components. 19 characteristic curves from 13 typical and 6 non-typical OC protective devices are chosen for curve-fitting. The numbers of fitting components required are determined by the maximum absolute values of errors for the fitted equation. All fitted equations are replaced by a versatile equation for the characteristics of OC protective devices which represents the characteristic model of a novel flexible OC relay, which in turn may be applied to improve the OC coordination problems in the sub-transmission and distribution systems.

• Prospectives of Industrial Chemistry
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• v.23 no.2
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• pp.12-22
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• 2020

전기변색 물질은 전압을 인가하였을 때 산화-환원 반응을 통해 흡수도나 투과도 같은 광학적 물성 변화를 보인다. 이러한 전기변색 물질에 기반한 전기변색 소자는 높은 투과도 변화, 낮은 구동 전압, 간단한 소자 구조 등 다양한 장점을 가지고 있어 차세대 투명 디스플레이로 각광받고 있다. 최근에는 이러한 전기변색 소자에 변색 특성 이외에 유연성 및 에너지 저장성 등 다양한 기능을 추가하는 연구가 활발하게 이루어지고 있다. 본 기고문에서는 전기변색 소자의 기본적인 구동 원리 및 다기능 개발 동향 등에 대해 알아보고자 한다.

• Journal of the Korean Data and Information Science Society
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• v.22 no.4
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• pp.735-740
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• 2011

In recent, electronic devices were able to develop and focus for ultra-compact size, intelligence, multifunction and broadband. Their SMPS is realized to ultra-compact size, light weight, high efficiency, high reliability, low noises. The power module which can be used to supply DC output from a commercial power supply (85 to 265 VAC). A switching power supply can be made easily by adding simply external circuit, such as microcontroller, a relay, etc. It would be apply to mostly electronic devices, and fit the global project "Saving energy". But we need to statistical analysis for a quality and performance about a load and an output voltage in product.

• Proceedings of the KIEE Conference
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• 2007.11c
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• pp.146-148
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• 2007

In this paper, we designed the bay control unit that is based on the microprocessors and integrates with the new technology of electrical, electronic, and mechanical fields. Nowadays the customers have required much more integrates multi protection relay, monitoring, control devices and power management for better and easier maintenance, performance, electrical system analysis and communication according to new trend of switchboard. This bay controller supplies those requirements of customers with easy handling and operation. This bay controller provides a graphic display with rear-lit liquid crystal LCD and push buttons as kinds of HMI. This bay controller provides the parameter setting program, various editors and fault recording and analysis program on Windows/95/98/NT/2000/XP for HMI. In addition, this bay controller can be set manually and this manual setting function helps user to interface easily.

• Journal of the Korea Institute of Military Science and Technology
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• v.26 no.2
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• pp.171-178
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• 2023

PCM data is result of air-vehicle flight test, this data is distributed for each engineers to analyze its condition. Since line-of-sight between the air-vehicle and the ground receiver cannot always be secured, remote PCM data recording system was claimed to be required. In this paper multi-function PCM data recorder has been described. This PCM data recorder was intended to place on inside of flight object. It can record about two hours in 32 GB SD card with maximum 7 Mbps data rate. RS-422/485 and RJ-45 interface enhanced accessibility for users. 5 V and 1 A power consumption and 19.5 mm × 152.5 mm × 102.3 mm allow to connect with mobile PCM devices. It acquired more than 190-minutes data in 12-times flight test. Also, it achieved military standard environmental test MIL-STD-810G to prove its stability and solidness.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.10
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• pp.983-988
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• 2016

Internet of Things Iranian people and things, things and things are connected through the Cloud. It can significantly save energy through a combination of LED lighting as a new ICT technologies and industry-to provide a human-centric, eco-friendly, and the content is embedded multifunction solutions that meet your needs, environment, implementation time according to user requirements, technology It can be systematized as converged next-generation lighting. In this paper, we have developed regarding whether the building in relation to the LED lighting control system using smart devices and Cloud-based user as a human connection through the board to the Arduino Yun lit LED lighting, wireless smart device or to the Cloud or off. After the Arduino Yun is connected to the Internet, taking the current date and time information from the Linux shell command used the way coming across the bridge (BRIDGE) its value.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.125.2-125.2
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• 2011

We are developing medium resolution cross-dispersed silicon grisms in the near IR region ($1.45{\sim}5.2{\mu}m$). The grisms will be installed in MIMIR, a multifunction instrument at the Lowel Observatory, USA. The two devices are designed to cover H and K band and L and M band simultaneously. Our goal is to make grism with R=3000 at 1.2 arcsec slit. The Silicon has high refractive index (n=3.4 at $1.5{\mu}m$) which enhances the resolving power by up to 5 times when compared to conventional material such as BK-7 (n=1.5 at 1.5 ${\mu}m$). The bonded grisms will be installed in a filter wheel for the uses switch from spectroscopic mode to imaging mode easily. Our device is compact and light weighted while it provides a decent resolving power. We produce monolithic grisms using e-beam lithography at the NASA JPL and chemically etching the grooves on the silicon prisms. Moreover, the main-disperser and cross-disperser will be contacted together by direct Si-Si bonding technique and eventually turn into one piece. The bonded pair offers more stability in terms of the layout of the spectrum and removes the Fresnel loss at the intersection of two grisms. We report on the proper wafer bonding steps through this research, and inspected the bonding quality thermally, optically and mechanically.