• 한국태양에너지학회:학술대회논문집
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• 2009.04a
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• pp.77-82
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• 2009

Many countries have been interested in sustainable development of buildings for environmental preservation. Thus it is significant to assess building envelopes in terms of $CO_2$ emissions owing to Kyoto Protocol. In this paper, a Double Skin Facade(DSF) installed in a general office building was assessed by $CO_2$ emissions(one of the performance-based assessment). To predict $CO_2$ emissions caused by the building energy consumption, the dynamic simulation program(Energy Plus) and $CO_2$ emission factor was used. Because DSF has various airflow regimes, pre-simulation runs were conducted to decide proximate optimal airflow regimes depending on seasonal variation. It is shown that the DSF can achieve 17.1-36.5% of annual energy savings.

• Journal of the Korean Solar Energy Society
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• v.24 no.4
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• pp.77-87
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• 2004

BIPV or double skin applied to the surface of the building, power and thermal load cannot both be increased. In the case of BIPV, because it is applied to the facade, incident solar energy decreases and efficiency drops off. The system in this paper complements these disadvantages and aims to decrease the heating & cooling load by transforming solar energy to electronic and thermal energy. The research in this paper is about the applicability of the clear PV attached double-skin system. And the PV electronic generation and the factors that affect the heating & cooling load such as the daily radiation, sun shading ratio, heating & cooling load, daylight luminance and glare distributions in the building are simulated.

• Journal of Radiation Protection and Research
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• v.35 no.2
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• pp.69-76
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• 2010

Prototype double-scattering Compton camera, which consists of three gamma-ray detectors, that is, two double-sided silicon strip detectors (DSSDs) as scatterer detectors and a NaI(Tl) scintillation detector as an absorber detector, could provide high imaging resolution with a compact system. In the present study, the energy resolution and the timing resolution of component detectors were measured, and the parameters affecting the energy resolution of the DSSD were examined in terms of equivalent noise charge (ENC). The energy resolutions of the DSSD-1 and DSSD-2 were, in average, $25.2keV{\pm}0.8keV$ FWHM and $31.8keV{\pm}4.6keV$ FWHM at the 59.5 keV peak of $^{241}Am$, respectively. The timing resolutions of the DSSD and NaI(Tl) scintillation detector were 57.25 ns FWHM and 7.98 ns FWHM, respectively. In addition, the Compton image was obtained for a point-like $^{137}Cs$ gamma source with double-scattering Compton camera. From the present experiment, the imaging resolution of 8.4 mm FWHM (angular resolution of $8.1^{\circ}$ FWHM), and the imaging sensitivity of $1.5{\times}10^{-7}$ (intrinsic efficiency of $1.9{\times}10^{-6}$) were obtained.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.1
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• pp.15-20
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• 2013

An energy detection based spectrum sensing is widely known to be susceptible to the noise power uncertainty. As one of the methods to resolve this problem, a cooperative spectrum sensing based on an energy detector with double thresholds has been published recently. However, its performance analysis under a fading channel has not been carried out yet. In this paper, we present a closed form of performance analysis of the scheme by extending our previous work on evaluating the performance of an energy detector in the presence of noise power uncertainty.

• Journal of the Korean Society of Radiology
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• v.10 no.6
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• pp.451-456
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• 2016

Radiation dose to patient is unavoidable when diagnosis is carried out using X-ray. Radiation diagnosis using dual energy X-ray was examined to verify the possibility of medical applications by SNR and image scoring. The dual energy X-ray was realized by combining together two image plates and filter of 0.5 mm thick Cu or Al. Under one X-ray exposure, contrast enhanced image was obtained using two images of image plates. The enhanced image showed higher SNR and image score compared to the first image which was the image recorded with the first image plate. The dual energy X-ray technique would be a very useful method for obtaining higher SNR image and for realizing very low dose, and could be applied to medical applications.

• Journal of Energy Engineering
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• v.25 no.4
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• pp.214-225
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• 2016

Gasification is one of the important contribution to resource recycling by conversion of biomass to a variety of energy sources such as alcohol, SNG etc., and to global warming prevention by reduction of green house gases such as $CO_2$. The aim of this study is to draw the optimal operation condition of dual fluidized-bed gasifier with biomass fuel, to verify SNG production efficiency and to establish the basis for the domestic commercialization of dual fluidized bed gasification. As a result, dual fluidized-bed gasifier has the optimal conditions at $826^{\circ}C$ with steam input 1,334 g/hr, air input 5.56 L/min. The carbon conversion is 81% and SNG production efficiency was $CH_4$ 92%.

• Electrical & Electronic Materials
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• v.2 no.1
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• pp.41-51
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• 1989

압전세라믹을 이용한 에너지포획형 단일체 대역통과필터는 '에너지포획'과 '탄생결합'이라는 두 중요한 원리를 사용한다. 본 연구의 주된 목적은 이중결합필터의 전극변수가 필터 특성에 미치는 영향을 규명하는 것이다. 예비단계로 에너지포획형 공진자의 부분전극의 단위 면적당 무게나 부분전극의 크기가 주파수특성에 미치는 영향을 조사하여 에너지포획을 야기시킬 수 있는 부분전극의 조건을 설정하였다.

• Proceedings of the KIEE Conference
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• 2005.11b
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• pp.64-66
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• 2005

최근 국제유가의 급등으로 인하여 에너지절약을 위한 방안으로 에너지절약기기의 기술개발과 에너지절약시설에 대한 투자가 급증하고 있다. 이중 한 분야가 열병합발전시스템으로 기존시스템에 비해서 에너지절감과 환경오염방지에 기여하는 시스템이다. 최근에 실증 연구과제로 설치한 6kW마이크로가스열병합시스템의 설계 설치하여 1,032시간 운전한 결과를 소개하고자 한다.

• 전기의세계
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• v.28 no.10
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• pp.3-8
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• 1979

정확하게 예측할 수는 없지만 현상태대로 나간다면 적어도 20년 후에는 석유생산의 피이크를 맞이하고 30년후에는 고갈될 것이라고 내다보는 전문가가 많다. 그렇다면 우리는 하루라도 빨리 석유를 대신할 수 있는 신에너지원을 찾아야만 할 것이다. 우리가 사용하고 있는 에너지는 크게 나누어 전기와 연료의 두가지로 된다. 전기에 대해서는 새삼스럽게 이야기 할것 없고 연료라는 에너지는 자동차를 달리게 하고 공장을 움직이고 빌딩의 온방에 쓰이는 등 이것역시 문명사회에 불가결한 것이다. 이중 문제가 되고 있는 것이 석유에 의한 발전 곧 확력발전부문의 전망디다. 한편 연료에 대해서는 종래 주종을 이루어왔던 석유를 대신해서 석탄의 액화, 가스화 물의 분해에 의해서 만들어지는 수소연료 등이 생각되고 있는데 과연 고갈된지 않는 새로운 에너지로서는 어떤 것이 있는가 또 현재 이들이 어느정도 개발되고 있는가를 알기쉽게 2-3회로 간추려서 소개해 보기로 한다.

• Journal of the Korean Vacuum Society
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• v.2 no.1
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• pp.58-64
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• 1993

이온선혼합의 열충격으로 야기되는 등방저기 또는 이방적 원자이동을 정량적으로 묘사하기 위한 모형을 제시하였다. 불순문 확산에서 원자들의 이동비는 구성원자들의 활성화에너지에 의존한다. 이 모형은 0에 가까운 혼합열과 비교적 높은 활성화에너지를 가진 이중층들의 실험결과들을 만족스럽게 예견한다. 불순물 확산에서 구성원자들의 활성화에너지가 크게 차이가 나는 계들은 이방적 원자이동을 보여주는 반면, 비슷한 활성화에너지를 가지는 계들은 등방적 원자이동을 나타낸다.