• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.41 no.3
• /
• pp.93-100
• /
• 2004

Test scheduling of SoC (System-on-a-chip) is very important because it is one of the prime methods to minimize the testing time under limited power consumption of SoC. In this paper, a heuristic algorithm, in which test resources are selected for groups and arranged based on the size of product of power dissipation and test time together with total power consumption in core-based SoC is proposed. We select test resource groups which has maximum power consumption but does not exceed the constrained power consumption and make the testing time slot of resources in the test resource group to be aligned at the initial position in test space to minimize the idling test time of test resources. The efficiency of proposed algorithm is confirmed by experiment using ITC02 benchmarks.

• The Journal of the Korea Contents Association
• /
• v.10 no.2
• /
• pp.120-129
• /
• 2010

MANET(Mobile Ad Hoc NETwork) is a collection of mobile nodes that are free to move and organize themselves in an arbitrary manner without any fixed infrastructures. These mobile nodes are connected by wireless links and act as routers for all other nodes in the network. As a router each node in MANET consumes its batteries when forwarding a message, and the selection of the best path to minimize the total power needed to route packets is needed to maximize the lifetime of all nodes. In this paper, we propose a routing protocol considering the remaining battery capacity of nodes in the routing paths. The proposed scheme prevents the battery of each node from being overused and increases the lifetime of the network.

• Proceedings of the Korean Information Science Society Conference
• /
• 2012.06a
• /
• pp.203-205
• /
• 2012

최근 컴퓨터 시스템에서는 동작 주파수 증가에 따른 전력 소모량과 높은 온도문제로 인해 CPU의 성능에만 의존할 수는 없는 상황이다. 이에 따라 GPU 병렬처리 연산능력을 CPU의 범용 데이터 처리에 이용하는 기술에 대한 관심이 높아지고 있다. 하지만 CPU와 GPU의 모든 자원을 활용하기에는 이에 따른 높은 온도와 전력 상승이 문제가 된다. 따라서 본 논문에서는 GPU의 전력효율과 성능 측면에서 최적이 되는 동작 주파수에 대한 분석을 수행하고자 한다. GPU를 활용하는 API인 CUDA를 이용하여 GPU의 동작 주파수 변화에 따른 성능 변화, 전력 변화 그리고 Energy Delay에 대해서 분석한다. 실험을 통한 분석 결과 동작 주파수의 증가에 따라 성능은 최대 30%이상 증가했고, 전력소모량은 최대 약18%의 증가를 보여주었다. 또한 Energy Delay도 최대 21% 향상되는 것을 확인할 수 있었다.

• KIPS Transactions on Software and Data Engineering
• /
• v.9 no.12
• /
• pp.419-430
• /
• 2020

This paper investigated methods to improve the forecasting accuracy of the electricity consumption prediction model. Currently, the demand for electricity has continuously been rising more than ever. Since the industrial sector uses more electricity than any other sectors, the importance of a more precise forecasting model for manufacturing sites has been highlighted to lower the excess energy production. We propose a double encoder-decoder model, which uses two separate encoders and one decoder, in order to adapt both long-term and short-term data for better forecasts. We evaluated our proposed model on our electricity power consumption dataset, which was collected in a manufacturing site of Sehong from January 1st, 2019 to June 30th, 2019 with 1 minute time interval. From the experiment, the double encoder-decoder model marked about 10% reduction in mean absolute error percentage compared to a conventional encoder-decoder model. This result indicates that the proposed model forecasts electricity consumption more accurately on manufacturing sites compared to an encoder-decoder model.

• Proceedings of the Korean Information Science Society Conference
• /
• 2004.10c
• /
• pp.220-222
• /
• 2004

이동 애드 혹 망을 구성하는 노드들은 일반적으로 배터리 전력을 사용하기 때문에 이들의 에너지 소모량을 줄이는 연구들이 각 계층에 대해 이루어져 왔다. 몇몇 연구들은 매체 접근 제어 프로토콜로 많이 이용되는 IEEE 802.11 DCF의 전력 소비량을 줄이기 위한 전력 제어 기법을 제시하였다. 기본 전력 제어기법(BASIC Power Control Protocol)은 RTS-CTS와 DATA-ACK 에 대해서 각각 다른 전력을 적용하는 것이다. RTS-CTS는 최대 전력으로 전송되고, DATA-ACK는 불필요한 에너지 낭비를 줄이기 위해 최소한 의 필요한 전력으로 전송하였다. 그러므로 DATA-ACK의 전송범위(transmission range)와 전송파 감지영역(carrier sensing range)은 RTS-CTS의 영역보다 작아진다. 전송파 감지영역에서 RTS-CTS를 감지한 노드들은 신호를 올바로 해석할 수 없으므로 NAV 값을 EIFS로 설정한다. 이 EIFS 구간은 충돌을 막기에는 너무나 짧기 때문에. EIFS 구간이 지난 후에 채널이 비어있는 상태로 간주하고 전송을 시도하게 된다. 이에 따라 DATA-ACK 수신에 있어서 충돌율이 증가하게 되고 네트웍 전체 처리량이 감소하게 된다. 본 논문에서는 기본 전력제어 기법이 가지는 문제점을 해결하고 전체 네트웍 처리량을 향상 시킬수 있는 새로운 전력제어(Power Control) MAC 프로토콜을 제안하였다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.3A
• /
• pp.221-229
• /
• 2007

In this paper, we propose and analyze the optimized sleep mode for a mobile node (MN) in IEEE 802.16e wireless metropolitan area networks. Because a MN in a sleep mode specified in 802.16e specification should maintain state information with the base station currently attached, it must renew sleep state with a new base station after handover which leads to unnecessary waste of battery power. Noting that the mobility pattern of a MN is independent of call arrival patterns, we propose an optimized sleep mode to eliminate unnecessary standby period of a MN in sleep state after handover. We also propose an analytical model for the proposed scheme in terms of power consumption and the initial call response time. Simulation studies that compare the performance between the sleep mode and the optimized sleep mode show that our scheme marginally increases initial call response delay with the huge reduction in power consumption.

• The KIPS Transactions:PartD
• /
• v.18D no.1
• /
• pp.45-56
• /
• 2011

The importance of low-power embedded system is being increased. The studies on low-power system have been performed in issues of hardware architecture and operating system. However because the behaviors of software control the working of hardware devices, the power analysis of software is one of critical issues in energy-efficient embedded system development. This paper proposes a technique to extract tasks from software design models with considering power consumption. We first define the criteria for task extraction, and then propose the way to separate out the task from UML 2.0 design models. Our technique can provide the chance to reduce the power consumption as well as to fulfill the performance requirement in the early phase of software development.

• Proceedings of the KIEE Conference
• /
• 2006.07d
• /
• pp.2041-2042
• /
• 2006

홈 네트워킹이 이슈화 되면서 많은 기능들을 내장한 홈 네트워크 제품이 개발되어지고 또한 판매되고 있다. 이러한 기능의 추가로 인하여 홈 네트워크 제품들의 소비전력 및 대기전력 또한 증가하고 있다. 본 고에서는 이러한 정보가전기기가 정상동작을 하지 않는 대기동작시의 전력소모량을 줄이기 위하여 기존에 많이 사용하였던 플라이백구조의 SMPS에 디지털 제어블럭 및 보조 SMPS를 이용하여 대기전력 소모량이 적은 디지털제어 전원공급시스템을 구현해 보았다. 이 시스템은 통신기능을 지원하도록 설계함으로써 네트워크 모뎀과의 통신을 통해 외부에서의 원격제어 및 모니터링이 가능하다.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.29 no.3
• /
• pp.685-692
• /
• 2019

Smart grid enables efficient power management by allowing real-time awareness of electricity flows through two-way communication. Despite its various advantages, threats to user privacy caused by frequent meter reading hinder prosperous deployment of smart grid. In this paper, we propose a privacy-preserving aggregation method exploiting fully homomorphic encryption (FHE). Specifically, it achieves privacy-preserving fine-grained aggregation of electricity usage for smart grid customers in multiple electrical source environments, while further enhancing efficiency through SIMD-style operations simultaneously. Analysis of our scheme demonstrates the suitability in next-generation smart grid environment where the customers select and use a variety of power sources and systematic metering and control are enabled.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.12 no.6
• /
• pp.303-309
• /
• 2012

Energy expenditure values were estimated based on the voice signals and body activities. Voice signals and body activities were obtained using PVDF contact vibration sensor and 3-axis accelerometer, respectively. Vibration caused by voices, activity signals, and actual energy consumption were acquired using data acquisition system and gas analyzer. With the use of power values from the voice signals and weight as independent variables, R-square of 0.918 appeared to show the highest value. For activity outputs, use of signal vector magnitude, body mass index, height, and age as independent variables revealed to provide the highest correlation with actual energy expenditure. Estimation of energy expenditure based on voice and activity provides more accurate results than based on activity only.