• 산업경영시스템학회지
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• 제43권1호
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• pp.7-15
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• 2020

It is a general phenomenon for manufacturers to provide vertically differentiated product line for more profit through improved market coverage. For such manufacturers, the compatibility between vertically differentiated products is an important decision issue. Some manufacturers provide full compatibility between high and low version products, whereas some provide only downward compatibility for the purpose of recommending high version product. In this study, the two representative compatibility strategies, full or downward, between vertically differentiated products produced by a single manufacturer are analyzed, especially under network externality and in the viewpoint of profit maximization. To do this we used a market model which captures the basic essence of vertical differentiation and network externality. Based on the proposed market model, the profit maximizing solutions are derived and numerically analyzed. The results can be summarized as follows : (1) Regardless of compatibility strategy, under network externality, vertical differentiation is always advantageous in terms of profit. (2) The full compatibility strategy is shown to be the most advantageous in terms of profit. In addition, it is necessary to make quality difference between differentiated products as wide as possible to maximize profit. (3) To gradually drive low version product out of the market and shift the weight pendulum of market to high version product, it is shown that the downward compatibility strategy is essential. Unlike intuition, however, it is also shown that in order to drive low version product out of market, it is necessary to raise the quality of the low version product rather than to lower it.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.1275-1276
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• 2015

Full wave electromagnetic simulation or fabricated models of an antenna are used to predict its radiation characteristics. In this work estimation of radiated power of an antenna based on its electrical model is presented. The computed radiated power using the electrical model have good agreement with the radiated power results obtained through the full wave electromagnetic simulation of the antenna model. The presented approach offers the advantage of saving of computation time of the full wave EM simulation.

• 한국경영과학회지
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• 제32권2호
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• pp.71-88
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• 2007

This study investigates the factors that influence the user's (postal workers') satisfaction with using PDAs in the Korea Postal Services. This study is concerned about the success of IS when employees are mandated to use IS to increase their productivity. The factors examined in this study include independent variables (information quality and system quality), dependent variables (perceived usefulness and user satisfaction), and mediator (compatibility with work). All these factors were found significant for causal relations. We especially notice the role of compatibility with work as full mediator.

• 자동차안전학회지
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• 제9권1호
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• pp.13-18
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• 2017

In recent years, NCAP regulations of many countries have induced automaker to improve the vehicle crashworthiness. But, the current NCAP regulations don't cover all types of traffic accidents. And rapid-increasing market share of compact cars and SUVs has brought for both consumer and automaker to pay more attention on crash compatibility. So, many countries have tried to develop the new crash test mode and update the present crash test mode. Especially, Euro NCAP has been developing a new impact protocol of the car-to-car frontal offset impact including the crash compatibility assessment. There are plans to introduce this new protocol in 2020, and it will be replaced the current Euro NCAP frontal offset impact. The test dummy in the front seats of this new test mode will be changed from 50% Hybrid-III male to 50% THOR male. This paper will address the vehicle responses, the occupant responses and the vehicle compatibility performance from a full vehicle crash test using the new car-to-car frontal offset test protocol of Euro NCAP.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 1997년도 학술대회
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• pp.101-106
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• 1997

Palplus system is a new European 16:9 wide screen TV format which has a full compatibility with standard PAL and the system has a advantage of improving picture quality by the reduction of cross color and cross luminance as well as making use of the full horizontal luminance bandwidth of the PAL system. We implemented European 16:9 PALplus Digital decoder(625/50/2:1) system using SVP(Serial Video Processor) IC and discrete helper demodulator.

• 항공우주기술
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• 제10권2호
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• pp.37-48
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• 2011

영상 레이더(SAR)는 날씨나 밤낮에 관계없이 전천후로 고해상도의 지구 관측을 가능하게 하는 강력하고 잘 정립된 마이크로웨이브 원격 탐사 기술이다. 한국항공우주연구원에서는 올해 발사될 예정인 우리나라 최초의 영상 레이더 위성을 개발해오고 있다. 영상 레이더 위성은 크게 위성 본체와 SAR 탑재체로 이루어진다. SAR 탑재체는 고출력의 전력을 SAR 안테나를 통하여 방사하기 때문에 설계 단계에서의 고주파 호환성 있는 설계와 시험단계에서의 고주파 호환성 검증이 실제 궤도 상에서 성능 보장을 위해서 무엇보다 중요한 절차이다. 본 연구에서는 영상 레이더 위성의 고주파 호환성을 위한 설계 기준과 검증 절차에 대하여 기술한다. 부가적으로 본 논문은 영상 레이더 위성의 RF 성능의 강건성 검증을 위한 RF 전체 방사 시험(RF 자체 호환성 시험)과 시험 형상 그리고 시험 결과에 대하여 기술한다.

• 한국인구학
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• 제34권3호
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• pp.179-209
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• 2011

본 연구는 한국보건사회연구원의 "2009년도 전국 결혼 및 출산 동향 조사" 패널자료를 활용하여 20~44세에 이르는 2,678명의 미혼 남녀(남 1,425명, 여 1,253명)가 생각하는 이상적인 일 가정 양립 방안, 성역할 태도 및 저출산 원인에 대한 견해 등을 성별 및 교육정도에 따라 알아보고 이들 사이의 관계를 탐색적으로 분석해 보았다. 이를 통해 향후 저출산 문제 해결을 위해 미혼 남녀들의 일 가정 양립을 어떻게 지원할 것이며, 이 과정에서 미혼 남녀의 성역할 태도가 어떻게 변화되어야 할 것인가를 유추해 보고자 했다. 연구결과를 정리하면, 첫째, 이상적인 일 가정 양립 방안은 미혼자의 성별에 따라 차이가 없었으나 교육정도에 따라서는 통계적으로 유의한 차이가 드러났다. 둘째, 이상적인 일 가정 양립방안과 부부 성역할 태도 및 성별 간 관계에 있어서는 여성에 비해 남성이 '남성은 직장, 여성은 가사'를 더 찬성했으며, 전일제일 보다 시간제 일을 선호하는 미혼자들이 '남성은 직장, 여성은 가사' 방안에 대한 찬성이 높았다. '남편의 자녀 돌봄 능력'에 대해서는 여성이 남성보다 그리고 2자녀를 두고 전일제로 일하겠다는 미혼자가 1자녀를 두고 전일제로 일하겠다는 미혼자에 비해 높은 평가를 보였다. 셋째, 두 자녀 이상을 두고 전일제로 일하고자 하는 미혼 남녀가 저출산 문제를 가장 심각하게 받아들이고 있었다. 넷째, 저출산 이유로 가장 높은 동의를 보인 것은 '양육비와 교육비용'이었으며 다음으로 '주택마련의 어려움'과 '취업여성의 증가'였다. "취업여성의 증가"를 저출산의 원인으로 여기는 정도는 남성보다 여성이 높게 나타났으며, 무자녀로 전일제 일하는 것을 원하는 미혼자들에게서 이러한 성향이 두드러지게 나타났다. 이러한 연구결과를 통해 일 가정 양립방안과 성역할 태도에 대한 기본적인 이해를 높일 뿐만 아니라 저출산 문제에 대한 정책적 개입방향을 제시하고자 하였다.

• 전기학회논문지
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• 제67권3호
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• pp.479-484
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• 2018

This paper describes domestic technical standard of Photovoltaic(PV) PCS(Power Conditioning Systems)-Characteristics of the utility interface. This standard tests utility compatibility and personnel safety and equipment protection of PV inverter performance functions. Especially utility compatibility part includes test items of 1)voltage, current and frequency, 2)normal voltage operating range, 3)DC injection, 4)normal frequency operating range, 5)harmonics and 6)waveform distortion, 7)power factor of PV inverter. Therefore in this paper each test item of domestic technical standard is studied and analyzed and finally full tested by PV inverter performance function.

• International Journal of Internet, Broadcasting and Communication
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• 제7권2호
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• pp.90-95
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• 2015

This paper describes IEC 61727 standard of Photovoltaic (PV) systems -Characteristics of the utility interface. IEC 61727 standard tests include utility compatibility and personnel safety and equipment protection of PV inverter performance functions. Especially utility compatibility part includes test items of 1) voltage, current and frequency, 2) normal voltage operating range, 3) flicker, 4) DC injection, 5) normal frequency operating range, 6) harmonics and 7) waveform distortion, 8) power factor of PV inverter. Also personnel safety and equipment protection part includes test items 1)loss of utility voltage, 2)over/under voltage and frequency, 3)Islanding protection, 4)response to utility recovery, 5)earthing, 6)short circuit protection, 7)Isolation and switching of PV inverter. In this paper, each item of IEC 61727 standard test is studied and analyzed and finally full tested by PV inverter performance function.

• Journal of electromagnetic engineering and science
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• 제13권4호
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• pp.199-207
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• 2013

Meeting electromagnetic compatibility (EMC) requirements can be a significant challenge for engineers designing today's electronic devices. Traditional approaches rely heavily on EMC design rules. Unfortunately, these design rules aren't based on the specific EMC requirements for a particular device, and they don't usually take into account the specific function of the circuits or the many design details that will ultimately determine whether the device is compliant. This paper describes a design methodology that relates design decisions to the product's EMC requirements. The goal of performance-based EMC design is to ensure that electronic designs meet EMC requirements the first time the product is tested. More work needs to be done before this concept reaches its full potential, but electronic system designers can already derive significant benefit by applying this approach to products currently under development.