• Journal of Korea Multimedia Society
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• v.14 no.3
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• pp.462-470
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• 2011

Retargetability is typically achieved by providing target machine information, ADL, as input. The ADL are used to specify processor and memory architectures and generate software toolkit including compiler, simulator, etc. Simulator are critical components of the exploration and software design toolkit for the system designer. They can be used to perform diverse tasks such as verifying the functionality and/or timing behavior of the system, and generating quantitative measurements(e.g., power energy consumption) which can be used to aid the design process. In this paper, we generate the energy consumption estimation simulator through ADL. For this goal, firstly, we describes the energy consumption estimation and monitoring informations on the ADL based on EXPRESSION. Secondly, we generate the energy estimation and monitoring simulation library and then constructs the simulator, RenergySim. Lastly, we represent the energy estimations results for MIPS R4000 ADL description. From this subjects, we contribute to the efficient architecture developments and prompt SDK generation through programmable experiments in the field of mobile software development.

• Journal of Information Processing Systems
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• v.2 no.1
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• pp.44-47
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• 2006

One of the critical issues in a sensor network concerns the detection of changes in data streams. Recently presented change detection schemes primarily use a sliding window model to detect changes. In such a model, a distance function is used to compare two sliding windows. Therefore, the performance of the change detection scheme is greatly influenced by the distance function. With regard to sensor nodes, however, energy consumption constitutes a critical design concern because the change detection scheme is implemented in a sensor node, which is a small battery-powered device. In this paper, we present a comparative study of various distance functions in terms of execution time, energy consumption, and detecting accuracy through simulation of speech signal data. The simulation result demonstrates that the Euclidean distance function has the highest performance while consuming a low amount of power. We believe our work is the first attempt to undertake a comparative study of distance functions in terms of execution time, energy consumption, and accuracy detection.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.5
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• pp.8-13
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• 2020

In this paper, the electric vehicle (EV) and internal combustion engine vehicle (ICEV) are compared for different driving cases. The EV exhibits a lower powertrain efficiency when driven on the aggressive driving cycle than when driven on the moderate cycle. In particular, EV powertrain efficiency is low when the battery state of charge (SOC) is low, but ICEV efficiency increases when the driving cycle changes from the moderate cycle to the aggressive cycle. Based on these results, attempts can be made to increase EV powertrain efficiency. EV charging before the battery power drops to a low charging state can reduce energy consumption by 2.7% for an urban area. Furthermore, ECO driving has a more significant effect on EVs than on ICEVs.

• Journal of Communications and Networks
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• v.14 no.2
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• pp.188-194
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• 2012

Cognitive networks (CNs) are capable of enabling dynamic spectrum allocation, and thus constitute a promising technology for future wireless communication. Whereas, the implementation of CN will lead to the requirement of an increased energy-arrival rate, which is a significant parameter in energy harvesting design of a cognitive user (CU) device. A well-designed spectrum-sensing scheme will lower the energy-arrival rate that is required and enable CNs to self-sustain, which will also help alleviate global warming. In this paper, spectrum sensing in a multi-user cognitive ad hoc network with a wide-band spectrum is considered. Based on the prospective spectrum sensing, we classify CN operation into two modes: Distributed and centralized. In a distributed network, each CU conducts spectrum sensing for its own data transmission, while in a centralized network, there is only one cognitive cluster header which performs spectrum sensing and broadcasts its sensing results to other CUs. Thus, a wide-band spectrum that is divided into multiple sub-channels can be sensed simultaneously in a distributed manner or sequentially in a centralized manner. We consider the energy consumption for spectrum sensing only of an analog-to-digital convertor (ADC). By formulating energy consumption for spectrum sensing in terms of the sub-channel sampling rate and whole-band sensing time, the sampling rate and whole-band sensing time that are optimal for minimizing the total energy consumption within sensing reliability constraints are obtained. A power dissipation model of an ADC, which plays an important role in formulating the energy efficiency problem, is presented. Using AD9051 as an ADC example, our numerical results show that the optimal sensing parameters will achieve a reduction in the energy-arrival rate of up to 97.7% and 50% in a distributed and a centralized network, respectively, when comparing the optimal and worst-case energy consumption for given system settings.

• Journal of Korea Society of Digital Industry and Information Management
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• v.17 no.1
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• pp.1-6
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• 2021

In this paper, to expand the use of standalone street lights, an algorithm for controlling LED energy consumption was proposed. The proposed method uses an LED module of a standalone street light divided into n zones. This is a method of reducing total power consumption by preventing the increase in power consumption due to high heat generation by weakly operating the entire LED according to the illuminance. When the amount of sunlight decreases, the whole LED operates weakly and then brightens, and unlike streetlight that act as streetlight, a method of dividing LEDs by area and limiting the number of LEDs operating according to illumination intensity was proposed. This is a way to use a lot of time with limited battery capacity by reducing the generation of heat that consumes the most power in streetlight. It is also a method of continuously changing the initial usage area to improve the total usage time of the LED substrate. As a result of the experiment, it was found that the proposed method extends the service time because it generates less heat than the conventional stand-alone streetlight.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.225-227
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• 2004

A sensor networkis composed of a large number of sensor nodes, which are densely deployed either inside the phenomenon or very close to it. One of the most important constraints on sensor nodes is the low power consumption requirement. Sensor nodes carry limited, generally irreplaceable, power sources. Therefore, while traditional networks aim to achieve high quality of service (QoS) provisions, sensor network protocols must focus primarily on power conservation. This paper presents the characteristics of energy consuming, average delay in 802.11 MAC, S-MAC that is specifically designed for wireless sensor networks. We analyze the energy consuming state in the 802.11 MAC in the simulation topology nodes, and measure average delay in 802.11 and S-MAC. Energy efficiency is the primary goal in this protocol design. 802.11 MAC is more efficient than S-MAC in the average delay, throughput. However S-MAC is an energy efficient protocol, a tradeoff between energy efficiency and delay.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.2
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• pp.42-47
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• 2014

The urban railway station is a structure that consumes a large amount of electric energy. Thus, the rationalization of using electric power is acutely demanded, but statistical data and design criteria that consider operating power load characteristics and structures, are very insufficiency. Therefore, this study investigated and analyzed that electricity consumption a year, characteristics, gross floor area of the station, structure, and etc, on the basis of Seoul metro station 1~4 line. Through regression analysis theory, we verified the overall features and the main tendency by analysis of specific parameter value(average, maximum, minimum, etc). The object of this study is the analysis about power density considering structure of the urban railway station, managing electric energy for the rationalization and setting a new standard of maintenance and construction.

• The Transactions of the Korean Institute of Power Electronics
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• v.21 no.2
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• pp.182-189
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• 2016

A modeling method of electric power network inside a fishing boat less than 5 tons is proposed for its high-energy efficiency with renewable energy sources. The power network inside the fishing boat consists of a diesel engine, a starter motor, an alternator, battery packs, and electric loads, which are connected in parallel. To obtain proper power network model, the voltage -current characteristics of the electric components are considered to develop elaborate electrical models under several load conditions. Measured data of the battery and alternator current include noise. By using an average method, the AC components from the power network of the fishing boat can be reduced, which is verified by KCL rule. Using the proposed power network model, the power generation of the alternator and the reduction of diesel consumption in the boat's engine are predictable under various operating conditions. The validity of the proposed methodology is verified by comparing simulation results with experimental measurements using statistical inferences.

• Ocean Systems Engineering
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• v.8 no.2
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• pp.119-166
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• 2018

The assessment of the potential for the design of marine renewable energy systems is reviewed and the current situation for marine renewable energy is promising. The most studied forms of marine renewable energy are ocean wind energy, ocean wave energy and tidal energy. Wind turbine generators include mostly horizontal axis type and vertical axis type. But also more exotic ideas such as a kite design. Wave energy devices consist of designs converting wave oscillations in electric power via a power take off equipment. Such equipment can take multiple forms to be more efficient. Nevertheless, the technology alone cannot be the only step towards marine renewable energy. Many other steps must be overcome: policy, environment, manpower as well as consumption habits. After reviewing the current conditions of marine renewable energy development, the authors analyzed the key factors for developing a strong marine renewable energy industry and pointed out the huge potential of marine renewable energy.

• 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.