• 한국정보통신학회논문지
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• 제19권9호
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• pp.2213-2221
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• 2015

안드로이드 기반 스마트폰 플랫폼에서 사용하는 온디맨드 거버너 (Ondemand Governor)는 CPU 사용률(Utilization)에 따라 CPU 동작 주파수를 조절한다. CPU 사용률의 변화량은 작업 스케줄링에 의해 영향을 받으며, CPU 동작 주파수 증감에 따라 스마트 폰의 전력 소비량도 증감한다. 따라서 작업 스케줄링 방식에 따라 변하는 CPU 사용률 및 동작 주파수는 스마트폰의 전력 소비에 영향을 미친다. 이에 온디맨드 거버너 정책을 작업 스케줄링 기법에 적용시켜 CPU 사용률 및 전력 소비, 그리고 작업 마감시한 측면에서 비교 분석하였다.

• 디지털산업정보학회논문지
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• 제17권1호
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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.

• ETRI Journal
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• 제39권1호
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• pp.30-40
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• 2017

In this study, we investigate topology control as a means of obtaining the best possible compromise between the conflicting requirements of reducing energy consumption and improving network connectivity. A topology design algorithm capable of producing network topologies that minimize energy consumption under a minimum-connectivity constraint is presented. To this end, we define a new topology metric, called connectivity efficiency, which is a function of both algebraic connectivity and the transmit power level. Based on this metric, links that require a high transmit power but only contribute to a small fraction of the network connectivity are chosen to be removed. A connectivity-efficiency-based topology control (CETC) algorithm then assigns a transmit power level to each node. The network topology derived by the proposed CETC heuristic algorithm is shown to attain a better tradeoff between energy consumption and network connectivity than existing algorithms. Simulation results demonstrate the efficiency of the CECT algorithm.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.545-546
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• 2008

This paper presents a low power CMOS low noise amplifier for UWB applications. To reduce the power consumption, two cascode amplifiers was stacked in DC. Designed with $0.18-{\mu}m$ CMOS technology, the proposed LNA achieves 20dB flat gain, below 3dB noise figure, and the power consumption of 5.2mW from a 1.8 V supply voltage.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.365-368
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• 1999

In this paper, we investigate the effect of adopting branch-penalty compensation schemes on the power performance of TLBs(Translation Look-aside Buffers) and instruction caches. We found that the double-buffer branch-penalty compensation scheme can reduce the power consumption of the TLBs and the instruction caches considered by up to 14-21.3%. The power consumption is estimated through simulation at the architectural level, using the Kamble/Ghose method

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2007년도 하계종합학술대회 논문집
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• pp.347-348
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• 2007

Most of the power consumption of a LCD TV is form the back light unit. Therefore, technoledge for decreasing the power consumption of the backlight unit is crucial for LCD Tvs. This research suggests a method of decreasing the power comsumption of LCD TV by analyzing the image's RGB info to dimm partitioned backlights independently.

• Journal of information and communication convergence engineering
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• 제5권3호
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• pp.200-204
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• 2007

The release of IEEE 802.15.4 PHY-MAC standard represents a milestone in developing of commercial wireless sensor network pursuing low power and low cost. In this paper, IEEE 802.15.4 Medium Access Control (MAC) protocol was analysed at the point of power consumption. This analysis measured the amount of the rest of power after transmitting data with beacon enabled mode and the power consumption of each node in the time period. ns-2 simulation is used to verify the analysis.

• 대한임베디드공학회논문지
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• 제4권2호
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• pp.50-54
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• 2009

In this paper, we address a novel system-level power management technique which is specifically targeted for an ARM 11 MPCore system. Our proposed solution is a DPM technique which includes process monitoring, real time power analysis, and policy application to reduce the power consumption while meeting the performance requirement. One of the main contributions of this paper is that we systematically infer QoS requirements of processes without getting any additional information from the application. When multiple processes are running under various user level policies, priorities of the policy application are determined in such a way that the overall system performance is maintained while power consumption is effectively managed. Experimental results show that our DPM technique is very effective in reducing power consumption without violating system's QoS requirements.

• Journal of Information Technology Applications and Management
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• 제14권2호
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• pp.1-10
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• 2007

The ubiquitous computing system is expected to be widely utilized in digital home, logistics control, environment/disaster management, medical/health-care services and other applications. The ubiquitous sensor network (USN) is a key infra-structure of this system. Nodes in the USN are exposed to adverse environments and required to perform their missions with very limited power supply only. Also the sensor network is composed of much more nodes. In case some node consumes up its power capacity under a certain required level, the network topology should change and re-routing/ re-transmission of data is necessitated. Resultantly communication protocols studied for conventional wireless networks or ad-hoc networks are not suitable for the sensor network. Schemes should be devised to control the efficient usage of node power in the sensor network. This paper proposes a routing algorithm to enhance the efficiency of power consumption for USN node and analyzes its performance by simulation.

• 전기학회논문지
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• 제59권11호
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• pp.1956-1963
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• 2010

Studies on the development of various energy management programs and real-time bidirectional information infrastructures have been actively conducted to promote the reduction of power demands and CO2 emissions effectively. In the conventional energy management programs, the demand response program that can transition or transfer the power use spontaneously for power prices and other signals has been largely used throughout the inside and outside of the country. For measuring the effect of such demand response program, it is necessary to exactly estimate short-term loads. In this study, the power consumption patterns in both individual and group consumers were analyzed to estimate the exact short-term loads, and the relationship between the actual power consumption and seasonal factors was also analyzed.