• Proceedings of the Korea Contents Association Conference
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• 2014.11a
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• pp.255-256
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• 2014

현재 대학공연장에 다양하고 화려한 조명을 많이 사용된다. 많은 수량이 필요한 등기구에 활용가능한 LED 등기구가 대체 선호되고, LED 등기구 장점인 에너지 절감에 대해 연구를 진행하였다. 설비와 장비에 대한 교체 비용을 포함하여 기존할로겐 등기구보다 LED등기구가 약3,000만원 정도 에너지 절감이 되는 것을 알 수 있었다.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2003.05a
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• pp.667-672
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• 2003

화석연료의 연소로 생성되는 $CO_2$는 지구온난화의 주범으로, 대부분 화력발전 등 에너지 산업에서 발생되는 배가스로 대기 중에 방출되고 있으며, 많은 나라들이 규제를 정하고 있다. 우리나라도 선진국과 같이 2008년부터 자발적 의무를 부담할 것을 요구하는 등 국제적인 요구가 증대되고 있다.(중략)

• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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• pp.226-227
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• 2003

다양한 응용분야에서 극초단 펄스의 쓰임은 점점 증가하고 있는 추세이고, 따라서 고에너지의 극초단 펄스를 방출할 수 있는 소형화된 source 개발연구는 현재 활발히 진행되고 있다 극초단 펄스를 증폭, 보다 높은 에너지를 손쉽게 방출하기 위한 방법의 하나인 광 파라메트릭 chirped pulse amplification(OPCPA)은 처음으로 Dubietis et al.에 의해 시도되었으며, 기본원리는 피코 혹은 나노초 펄스의 고에너지를 효율적으로 시간상 stretching된 극초단 펄스로 전이하는 것이다. (중략)

• Journal of Energy Engineering
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• v.4 no.1
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• pp.153-161
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• 1995

건식 제련법에 의한 자용제련 공정에 대하여 공정비용을 최소화시키고 최적 조업조건을 제시할 수 있는 최적화 모델을 개발하였다. 본 모델은 Outokumpu 공정을 기본으로 하여 물질 및 에너지 수지식과 비용 방정식을 포함하였으며 주어진 공정조건에서 공업용 산소량, 탄화수소 연료량, 원료 정광의 구리함량, matte의 구리함량 및 전기료 등이 공정비용에 미치는 영향을 계산할 수 있었다. 모델에 의한 계산결과 25% 구리정광을 원료로 하여 자용제련을 할 경우 matte의 최적 구리함량은 65%, 산화용 가스의 최적 산소함량은 53.4%, 최소 공정비용은 $9.22/ton정광이었다.

• Journal of Energy Engineering
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• v.24 no.4
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• pp.1-10
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• 2015

For successful operation of waterflooding which is one of secondary recovery methods, suitable water injection allocation is important to increase oil recovery. Well allocation factor(WAF) which is one way to quantify the injector and producer connectivity, is utilized to allocate water injection of waterflooding. Static WAF cannot represent the field condition and can induce incorrect value. To compensate for limitation of static WAF, modified WAF which includes several parameters that affect patterns including well radius, distance between wells, and injection rates is proposed. In this study, static and modified WAFs were applied to injection optimization of waterflooding and results by each WAF were compared. In case of modified WAFs, produced water were less and produced oil were more than case of static WAF especially in big change of distance between producer and injector. Therefore, modified WAFs can allocate water injection more efficiently than static WAF.

• Korea Petroleum Association Journal
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• no.3 s.205
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• pp.14-15
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• 1998

노사정위원회가 경제위기 극복을 위한 고통분담의 대타협을 마침내 일궈냈다. 노동계ㆍ기업ㆍ정부 등 3대 경제주체의 대표가 지난 1월 15일 노사정위원회를 구성하고 20일 제1차 공동선언문을 발표한데 이어 2월 6일 협의를 마무리짓고 제2차 공동선언문을 발표한 것이다. 협의과정에서 계속된 철야회의, 팽팽한 의견대립, 일부 대표의 회의장 퇴장 등 우여곡절이 적지 않았다. 그러나 나라 전체에 걸친 신속하고도 근본적인 개혁의 단행없이는 도저히 극복할 수 없는 총체적 국가위기라는 데 인식을 같이 하고 공정한 고통분담으로 경제위기를 극복하고자 의견을 모았다.

• Korean Journal of Optics and Photonics
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• v.7 no.3
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• pp.227-231
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• 1996

The reflection spectrum of a $2H-PbI_2$ single crystal grown by vapour phase method were measured at 10 K near the fundamental absorption edge. The n= 1,2,3 Wannier exciton series and $A_{EP}$ reflection line were obtained from the reflection spectrum. Based on the 2nd phonon energy in the Raman spectrum, which is different from Nagamune's report, we suggest that $A_{EP}$ line is due to the bound state between the n=2 exciton and the 2nd phonon which surmise that this is LO phnon due to the second Raman process. The L-T splitting energy of n=1 exciton line was 6.56 meV and was consistent with the emission spectrum. The temperature dependence of the reflection spectrum showed that n=1 exciton peak was shifted to longer wavelength while, as the temperatre is raised, the sharpness of that with the increase of the L-T splitting energy decrease. From Wannier exiton series, the exciton binding energy and exciton radius was 30 meV and 14$\AA$, respectively.

• Korean Journal of Materials Research
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• v.11 no.6
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• pp.508-511
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• 2001

Experimental studies of the brittle-ductile transition (BDT) for pre-cracked sapphire single crystals were carried out. The BDT temperature in sapphire single crystals were $1000\pm$$25^{\circ}C$ and 1100$\pm$$25^{\circ}C$ at constant strain rate 3.3$\times$$10^{-5}$/sec and 3.3$\times$$10^{-6}$/sec, respectively. With aid of the BDT model, the activation energy for prism plane slip {1120} <1100> dislocation velocity was in the range of 4.6$\pm$2.3eV This activation energy for dislocation velocity with BDT model was compatible with the result of the dislocation velocity (3.8eV) using the etch-pit techniques.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.17 no.1
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• pp.58-67
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• 1992

Optical absorption and photoluminescences(PL) of MgGa2Se4 and MgGa2Se4 : Co2+ single crustals were guown by the Bridgman method have been investigated in the visible and near-in frared regions. The optical absorption spectrum showed three absorption peak at 760 nm(13158nm, -1, 1.63eV), 1640nm(6097cm-1, 0.75eV).and 2500nm(4000cm-1,0.49eV) which are assigned the electronic transitions between the ground state and excited states of Co2+ ions with Td sym-metry in MgGa2Se4 host lattice. In PL spectrum the visible emission bands as well as the infrared emission band in these single cuystals are obserned. The visible emission bands are explained due to the radiative transitions of electrons from quasi continusly distributed tarps below the bottom of the conduction band to acceptor levels above the top of the valence band in the proposed energy level scheme. At the same time, it is considered that the infrated emission bands are attributed to electron transitions from the deep levels to the acceptor levels. The mechanism of the optical transition os well explained in terms of the energy diagram of MgGa2Se4.

• Polymer(Korea)
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• v.38 no.5
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• pp.626-631
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• 2014

Water purification requires a large amount of energy that can cause pollution problems. For this reason, forward osmosis (FO) has attracted intense interest that required a relatively low amount of energy for water purification. The forward osmosis has a serious problem that it needs drawing agents creating osmotic pressure to extract water from contaminated water. In this study, a copolymer of zwitterionic moiety and an interpenetrating polymer network (IPN) hydrogel based on thermo-responsive polymer hydrogel, poly(N-isopropylacrylamide) (PNIPAM) were prepared and attached on FO membranes, which successfully played the role of drawing agents. In the copolymer hydrogel, its swelling ratio was improved, but thermo-sensitivity was decreased. The swelling ratio and thermo-sensitivity of IPN hydrogel was lowered. We could confirm that swelling ratio is related to osmotic pressure.