• Proceedings of the KSR Conference
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• 2010.06a
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• pp.171-176
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• 2010

Railway has recently played an important role in preventing global warming caused by green house gases and furthering a low carbon green growth, The various railway research centers have conducted facilitated studies on saving energy. In particular, urban railway has emerged as the best means of public transportation in terms of punctuality, safety and environmentally friendliness. There are various ways to save energy in terms of operation of urban railway system, and they can be generally divided into hardware aspects that pertain to structure of vehicles and development of control system and software aspects that pertain to effective operation of trains based on operation patterns and diagram control. In this paper, we investigated drive assistance system for railway energy efficiency. The railway operation patterns and train diagram management programs were researched.

• Proceedings of the KIPE Conference
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• 2008.06a
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• pp.97-99
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• 2008

It is possible to suppress voltage drops, power loading fluctuations and regeneration power lapses for DC railway systems by applying an energy storage system. Recently the electric double layer capacitor (EDLC) of the rapid charge/discharge type has been developed and used in wide ranges. The on board energy storage system with supercapacitor for railway vehicles presented in this paper seems to be a reliable technical solution with an enormous energy saving potential. In this paper, an efficient charge and discharge control method of a bidirectional DC-DC converter using the supercapacitor is proposed.

• Korean Journal of Chemical Engineering
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• v.35 no.12
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• pp.2336-2347
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• 2018

The azeotrope of methyl acetate methanol and water was isolated using extractive distillation with water as entrainer. The pressure-swing extractive distillation (PSED) process and vapor side-stream distillation column (VSDC) with the rectifier process were designed to separate the methyl acetate, methanol and water mixture. It was revealed that the VSDC with the rectifier process had a reduction in energy consumption than the PSED process. Four control schemes of the two process were investigated: Double temperature control scheme (CS1), $Q_R/F$ feedforward control of reboiler duty scheme for PESD (CS2), $Q_R/F$ feedback control scheme for VSDC (CS3), the feedback control scheme of sensitive plate temperature of side-drawing distillation column to dominate the compressor shaft speed (CS4). Feed flow and composition disturbance were used to evaluate the dynamic performance. As a result, CS4 is a preferable choice for separation of methyl acetate-methanol-water mixture. A control scheme combining the operating parameters of dynamic equipment with the control indicators of static equipment was proposed in this paper. It means using the sensitive plate temperature of side-drawing column to control the compressor shaft speed. This is a new control scheme for extractive distillation.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.43 no.4 s.310
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• pp.15-22
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• 2006

Nowadays, there is called energy saving, that it is accomplished with a lot study and application development as according to demand of all around world. It is using to network device of wire or wireless such as internet, lan, plc, and zigbee and that we should be accomplished to study about method that spending a little cost to fatal error in control system that be expected of frequent occurrence on network, and that have method to do construction a little bit tried out. Also, in that such a embedded system with network function case, there is important thing that it is remote management to network node and control methods to trust because firmware upgrade have the advantage of more than the other device. In this paper, we have verified through a result of experiment for efficient remote management and control method as previously stated in this paper, that it is area of the PLC for sensor node and doing management to relay, and implementation of the LACC which is core part of the ESS, and in order to get a result to trust from doing analysis of capacity and test.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.2B
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• pp.130-137
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• 2012

In this paper, we propose core and edge router architectures with LPI(Low Power Idle) for reducing energy consumption in OBS networks. The proposed core router architecture is comprised of a BCP switch, a burst switch, line cards and sleep/wake controller for LPI. When the offered load of network is low, sleep/wake controller can change the state of the core router line card from active to sleep state for saving the energy after receiving network control packet. The edge router consists of a switch for access line card, a SCU and OBS edge router line cards. The LPI function in edge router line card is performed through network level control by network control packet, individually. Additionally, PHY/transceiver modules can transition active state to sleep state when burst assemble engine generates new bursts. To evaluate the energy saving performance of proposed architecture with LPI, the power consumption of each router is analyzed by using data sheet of commercial router and optical device. And, simulation is also performed in terms of sleep time of PHY/Transceiver through OPNET.

• The KIPS Transactions:PartC
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• v.17C no.6
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• pp.459-464
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• 2010

Due to the application-specific nature of wireless sensor networks, the sensitivity to such a requirement as data reporting latency may vary depending on the type of applications, thus requiring application-specific algorithm and protocol design paradigms which help us to maximize energy conservation and thus the network lifetime. In this paper, we implement and evaluate a novel delay-adaptive sensor scheduling scheme for energy-saving data gathering which is based on a two phase clustering (TPC), in wireless sensor networks. The TPC is implemented on sensor Mote hardwares. With the help of TPC implemented, sensors selectively use direct links for control and forwarding time critical sensed data and relay links for data forwarding based on the user delay constraints given. Implementation study shows that TPC helps the sensors to increase a significant amount of energy while collecting sensed data from sensors in a real environment.

• Science of Emotion and Sensibility
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• v.18 no.2
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• pp.45-54
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• 2015

This study carried out an experiment to identify subject's work effectiveness and energy saving effect using LED light. Towards this end, this study configured nine various lighting environments in order to control PWM (Pulse Width Modulation) and illuminance (lux), which are the characteristics of LED light. The PWM ratio of LED light was set as R:G:B=1:1:1, R:G:B=4:1:5, and R:G:B=8:7:7, respectively, and illuminance (lux) was set as 400 lx, 700 lx, and 1000 lx, respectively. In addition, the indoor environment was set temperature $20-24^{\circ}C$, humidity 50%-60%, and the amount of clothing 1. This study analyzed work effectiveness and energy consumption in nine lighting environments, each. Error correction was performed for work effectiveness analysis, and cumulative power consumption was measured in each lighting environment for energy consumption analysis. According to experiment results through the lighting environments suggested in this study, accuracy and spent time effectiveness were good in 700lux and higher than 400lux. For spent time, the best effectiveness was revealed in the suggested PWM ratio, R:G:B=8:7:7. The lowest power consumption on each illuminance (lux) was revealed in the order of R:G:B=8:7:7, RGB=1:1:1, and R:G:B=4:1:5. Therefore, pulse-width modulation effect is proposed in this paper was found to affect the efficiency and energy saving.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.3
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• pp.95-99
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• 2013

The maximum power analysis simulator took advantage of the facilities and power consumption reduction simulator test scenario development and testing of improvement in the scenario. As a maximum demand power controller, Maximum power analysis simulator performs control and disperasion of maximum demand power by calculating base power, load forecast, and present power which are based on signal of watt-hour meter to keep the electricity under the target. In addition, various algorithms to select appropriate control methode on each of the light installations through the peak demand power is configured to management. The simulation shows the success of control power for the specified target controlled by five sequential lighting installations.

• Journal of Energy Engineering
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• v.25 no.2
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• pp.79-85
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• 2016

This paper presents an advanced energy demand management for buildings. It is important to aggregate a various demand side resource which is controllable on demand response environment. Previous demand side algorithm for building is mostly restricted on single building. In this paper, we suggest energy demand management algorithm for many buildings. And, this paper shows the procedure to apply suggested demand management algorithm.

• Journal of Navigation and Port Research
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• v.37 no.2
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• pp.137-142
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• 2013

The displacement Deep-V catamaran concept was developed in Newcastle University(UNEW) through development of the systematic Deep-V catamaran series. One of the most important Deep-V catamaran launched to date is Newcastle University's own multi-purpose research vessel, The Princess Royal. The vessel was launched in 2011 and enhanced the Deep-V catamaran concept further with the successful adoption of a novel anti-slamming bulbous bow and tunnel stern for improved efficiency. It was however identified that the vessel has substantial amount of dynamic trim that limited the visibility of the captain. The dynamic trim also increased the wave-making resistance thereby preventing the vessel from attaining its maximum speed in certain sea states. This paper therefore presents the application of devices such as Trim Tabs, Interceptors, Transom Wedges and Integrated Transom Wedges-Tabs to control the dynamic trim and improvement of fuel efficiency of the vessel. All of these energy saving devices were fitted into a model for tests in Newcastle University's Towing Tank. Model test verification confirmed that the optimum appendage was the interceptors, they produced a 5% power saving and 1.2 degree trim reduction at 15 knots, and investigations of full scale trials will be scheduled with and without application of device to compare the improvement of performance.