• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.2
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• pp.8-15
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• 2006

To reduce costs and address other practical concern related to architectural lighting, we have been involved in various aspects of advanced daylighting design and control. If we look toward future building trends, we see that the advanced has already successfully deployed such complex lighting control systems. This paper takes a broad view of what advanced manufacturers have done to develop energy efficient lighting control technologies such as sensors, lumen maintenance, time of day scheduling, peak demand reduction and so forth. First of all strategies, daylighting controls would also need to be commissioned to respond to the specific daylighting signature of the zone. To translate the daylight in term of the amount of energy savings, an electric lighting system is designed and automatic on-off control system integrated with the contribution of daylighting has been applied to the operating of the artificial lighting. The lighting analysis program, Lumen-Micro predicts the optimal layout of conventional fluorescent and incandescent lighting fixtures to meet the designed lighting level and calculates unit power density, which translates the demanded amount of lighting energy.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.15 no.1
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• pp.118-124
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• 2001

To guide the esti-on of electric d e d and energy saving, this proposed the Power Laaddensity, Elechic pwer consumption and the installed state of Power facility. For this purp~se, it wasconducted a questionnaire survey of the consumption-cattern of Electric power in 1W a p a r t t housings.As a 1-esult it is found that (i) the d m u m value of Power Load density is 7.70[~A/m"l, (ii) the avtragevalue of Power Load dens'||'&'||' is ~ . ~ A / mm' dl (iiijthe average load rate is Ed[%]. Also, the consumptionof electricity one year at tlie whole a m n t s of couniry is 14,0X[GWyearl, it was equivalent to 7[%1 ofthe total-consunmhon of electricity one year at the whole of co1mtnr. co1mtnr.

• Proceedings of the Korean Society of Computer Information Conference
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• 2011.01a
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• pp.107-108
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• 2011

Since the development of railway technology, the current urban Railway the first train line in the country for safe operation control automatic/unattended operation, automatic train operation equipment available (ATO) on time and reliable operation has introduced. ATO Automatic operation controlled by the value (Target velocity) and the feedback value (Actual velocity) by the error between the backing and braking of the train by repeated low energy efficiency. In this paper, given a fixed distance stations between time operation with minimal energy in the driving characteristics and driving trains are modeled. Therefore, in line 5 real route time sectional drive straight sections for experimental data analysis / draft Section / curved and section of the train on that line is selected according to the changing driving patterns to minimize the energy optimal driving patterns were presented.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.5
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• pp.81-88
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• 2015

바이오매스는 유망한 신재생 에너지이다. 바이오매스는 액체 및 기체 연료로 전 환 할 수 있고, 다양한 공정을 통해 열 및 전력을 생산시키는데 사용된다. 바이오매스 가스화 공정은 바이오매스를 일산화탄소, 이산화탄소, 수소 및 메탄으로 이루어진 합성 가스로 전환시키는 기술이다. 바이오매스를 이용한 합성 가스 생산 및 활용은 세계적으로 늘어나는 에너지 필요성을 충족시킬 수 있는 대체에너지이다. 현재, 바이오매스 가스화의 주요 원료는 목질계 우드 칩을 주로 사용하고 있지만, 일반적으로 우드칩의 경우 수분을 다량 함유하고 있기 때문에 가스화 공정을 위해서는 별도의 건조처리를 필요로 한다. 우드칩의 건조에는 많은 에너지가 소요되고, 다량의 우드칩 건조에는 시간과 기상 및 공간적인 환경에 영향을 받는다. 본 연구에서는 미건조 우드칩의 가스화 공정을 위하여 미건조 우드칩에 숯을 각각 10, 30, 50 % 비율로 혼합하여 실험을 수행하였고, 실험결과 생산된 합성가스의 CO 농도 는 숯의 비율에 따라 14.9 ~ 25.6 % 증가되는 경향을 나타내었지만, 반대로 $CO_2$ 및 $CH_4$ 농도는 감소하였다. 이에 따라 합성가스 생산을 위한 미건조 우드칩과 숯의 최적혼합비율은 약 30 %로 판단되며, 발열량은 $1285.7kcal/Nm^3$, Gas yield는 $2.3Nm^3/kg$ 로 나타났다. 이에 적절한 숯의 혼합사용은 미건조 우드칩의 직접적인 가스화에 도움이 될 것으로 사료되며, 바이오매스 건조 공정에 필요한 에너지를 절약할 수 있을 것으로 판단된다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.7
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• pp.965-971
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• 2017

The primary objective of this study was to assess the energy efficiency performance of an optimized hull form capable of saving energy based on existing vessels. The bow shape of existing vessels was investigated, giving consideration to design draft and speed. Resistance performances were also assessed for existing vessels according to operating conditions. Commercial CFD codes and model test materials were used to assess effective power. An optimized hull form with minimum resistance was selected given real operating conditions. The effective horsepower of existing and optimized vessels was estimated at three speeds. Resistance performance for an optimized vessel showed a 6 % improvement in effective horsepower at design speed (12 knots) compared to existing vessels. Quasi-propulsive efficiency employed experimental data, while energy efficiency performance was analyzed based on operating days, bunker fuel oil C cost, daily fuel oil consumption and specific fuel oil consumption. Energy efficiency performance for an optimized vessel showed a gain of 30 million won per year in reduced costs at design speed (12 knots) compared to existing vessels.

• Journal of Korean Tunnelling and Underground Space Association
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• v.13 no.5
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• pp.371-383
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• 2011

It is important to secure illumination for the driver's safety because the tunnel is a space for changing brightness quickly, and lighting fixtures of the tunnel have consumed a lot of electric lighting energy for operating in both the daytime and at night. This study aims to evaluate daylighting performance of Mirror Reflector System for luminous environment improvement of tunnel space by using RADIANCE simulation program. The results of simulation show that illuminance of bar type is higher than illuminance of pole type at 20 m from the tunnel entrance.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.11
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• pp.199-204
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• 2012

The study for developments and economics about the energies from the global warming is very active. For the effective saving and the spanning of the life extension about the 19% rates for the illumination system spending power about the whole electric energies, we proposed the new type of the current control method using a mixing system of the frequency modulation together with the pulse width modulation for the half-bridge power instrument. And we proved the excellence and the stability for our suggested system and analyzed the characteristics.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.854-857
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• 2008

Wireless sensor consists of an internal power source which has limited life time. Several MAC protocols have exploited scheduled sleep/listen cycles to conserve energy in sensor networks. Duty cycle is a user-adjustable parameter in low duty cycle MAC protocols, which determines the length of the sleep period in a frame. The sire of duty cycle has direct effect on the Performance of MAC Protocols. In this Paper, we simulated TEEM (A Traffic Aware, Energy Efficient MAC) and S-MAC in NS-2 with different duty cycle values and analyze how duty-cycle effects on the performance and energy consumption of both the protocols.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.5
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• pp.65-70
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• 2013

In this paper, we propose a multi-hop cooperative transmission protocol to obtain energy savings in static wireless networks. Each terminal in the network is equipped with a single antenna and each receiver uses equal gain combining technique (EGC) to combine received signals. We also propose a power allocation strategy which optimizes the total transmit power at each stage. Monte-Carlo simulations are presented to evaluate and compare performance of the proposed protocol with the multi-hop direct transmission (MDT) and the cooperative routing protocol proposed by Khadani [8], in terms of the average total transmit power and the average number of required stages.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.277-278
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• 2008

에너지절약에 대한 중요성과 관심으로 효율을 높이고 인버터 구동에 대한 서지내구성이 강화된 전동기용 절연소재의 개발에 관심이 커지고 있다. 최근 나노기술의 발달로 전동기용 에나멜 절연재에 나노입자를 강화하여 성능과 효율의 향상이 크게 개선되고 있다. 본 연구에서는 졸겔 제조법으로 PAI-MCS-A계 나노 하이브리드형 에나멜을 제조하여 기존 수지와의 전기적 특성을 비교 분석하였다. 강화입자로 선택한 나노 MCS 의 조성을 최대 30wt% 범위에서 메트릭스 수지와의 상안정성이 확인되었다. 특히 내아크성, 트래킹 시험에서 우수한 내구성이 나타났으며 이는 전동기용 에나멜 및 전력용 절연코팅용으로 사용이 기대된다. 전기적 절연, 섬락, 누설전류 등에 영향을 미치는 K, Na 값이 기존 다른 연구보고와 유사한 값을 가지고 있는 것을 확인하였다.