• Communications for Statistical Applications and Methods
• /
• 제27권6호
• /
• pp.589-602
• /
• 2020

The development of smart grids has enabled the easy collection of a large amount of power data. There are some common patterns that make it useful to cluster power consumption patterns when analyzing s power big data. In this paper, clustering analysis is based on distance functions for time series and clustering algorithms to discover patterns for power consumption data. In clustering, we use 10 distance measures to find the clusters that consider the characteristics of time series data. A simulation study is done to compare the distance measures for clustering. Cluster validity measures are also calculated and compared such as error rate, similarity index, Dunn index and silhouette values. Real power consumption data are used for clustering, with five distance measures whose performances are better than others in the simulation.

• 한국산업융합학회 논문집
• /
• 제23권6_2호
• /
• pp.949-956
• /
• 2020

It's important to measure fuel consumption of vehicles. It's possible to monitor green house gas from vehicles for various traffic conditions with the measured data. It's effective to eco-drive for drivers with fuel consumption data also. There's a display of fuel consumption in the modern vehicles, but it's not useful to get the data from the display. An estimating method for fuel consumption of a vehicle is suggested in the study. It's a simple but an effective method using GPS data. The GPS data(speed, acceleration, road slope) and vehicle data(weight, frontal area, model year, certified fuel economy) is necessary to estimate the fuel consumption for the method. It calculates driving resistance force to estimate engine power. Then it estimates the necessary fuel consumption to maintain the engine power with fuel-power conversion factor. The conversion factor is corrected with certified fuel economy, model year and rated power. The precision of the methods is checked with road test data. The test driving data was measured with GPS and OBD. The error of the estimated fuel consumption for the measured one is about 1.8%. But the error is large for the 1000 and 100 data number from the total data number of about 10,000. The error is from the larger change range of the GPS data than the one of the measured fuel consumption data. But the proposed estimating method is useful to percept the fuel consumption change for better fuel economy with simple gadget like smart phone or other GPS instruments.

• 전기학회논문지
• /
• 제58권11호
• /
• pp.2281-2285
• /
• 2009

Powerline communication is the data signal which is modulated by carrier frequency through the installed powerline at in-home or office is transmitted and received signals are separated into data signal with using band-pass filter which cent-frequency is carrier frequency. The home gateway, an equipment which works as an gateway for ubiquitous home network, relays all functions of a home network. The home gateway must always be connected in order to provide seamless services. However it gives unfavorable power consumption. Therefore the needs for working in maximum power saving mode while there is no data traffic and for invoking to the normal function when it is necessary. So, in this paper we survey the development of low power PLC modem monitoring of power consumption and breaking abnormal power in the home Network.

• 한국정보과학회:학술대회논문집
• /
• 한국정보과학회 2003년도 봄 학술발표논문집 Vol.30 No.1 (C)
• /
• pp.253-255
• /
• 2003

Electricity is the prime commodity in mobile device, e.g. smart phone, PDA, MP3 player and etc. This strict restriction on power consumption requirement of the mobile device puts unique demand in designing hardware and software components of the device. In this paper, we address the issue of minimizing the power consumption in retrieving the continuous media data from the disk drive for real-time playback purpose. Different from the legacy text based data, real-time multimedia playback requires that the storage supplies the data block continuous fashion. This may put immense burden on the power scarce environment since the disk Is required to be active for the entire playback duration. We develop elaborate algorithm which carefully analyzes the power consumption profile of the disk drive and which establishes the data retrieval schedule for the given playback. It computes the amount of data blocks to read, the length of active and standby period. According to our simulation result, the ARM algorithm exhibits superior performance in continuous media retrieval from the aspect of power consumption to legacy playback scheme.

• JSTS:Journal of Semiconductor Technology and Science
• /
• 제1권3호
• /
• pp.167-181
• /
• 2001

A stepwise driving method was used for reducing the AC power consumption in a TFT-LCD. The AC power takes the largest portion of the total power consumption of a TFT-LCD. Experimental results confirmed that the AC power saving efficiency reached up to 75% when a 5-stepwise driving with each step time of $2\mu$ sec was applied to a 14.1 inch-diagonal XGA TFT-LCD. The second largest component of power consumption called the DC power comes from the quiescent currents in Op-amps. A simple and efficient architecture was proposed in this work to reduce this DC power consumption: Half of the Op-amps have the 5V-supplies, and the rest half have the 10V-supplies, and two Op-amps are shared by adjacent two channels. Measurements of test circuits showed that this simple method could reduce over 40% of the DC power consumption..

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2009년도 추계학술대회
• /
• pp.1026-1029
• /
• 2009

센서 네트워크는 센서 노드들이 배치된 후 충전이 사실상 어렵기 때문에 에너지를 효율적으로 사용하는 것이 중요하다. 이에 본 논문에서는 Modified-CBPER이 CBPER의 데이터 공고 패킷의 공고 범위를 줄여 전송 횟수를 감소함으로서 에너지 소비를 감소시킨 점에 착안하여 추가적으로 데이터 공고 범위를 줄여 에너지 소비 감소를 도모하는 방법을 제안한다. 제안하는 EM-CBPER(Enhanced Modified CBPER)은 데이터 요청을 하고 데이터를 전송하는 과정에서의 에너지 소비는 기존의 알고리즘들에 비해 다소 증가하나 전체 전송량에서 큰 비중을 차지하는 데이터 공고 패킷의 전송 횟수를 줄임으로서 전체적인 에너지 소비를 줄인다.

• 교육녹색환경연구
• /
• 제11권2호
• /
• pp.19-27
• /
• 2012

This study was carried out in order to establish the estimation equation for school power consumption using regression analysis based on collected power consumption for two years of weather data and schools are located in Central Changwon and Masan district in Changwon city. (1) The power consumption estimation equation for Heating and cooling is calculated using power consumption per unit volume, the difference between actual power consumption and results of estimation equations is 4.1%. (2) The power consumption estimation equation for heating load is showed 2.6% difference compared to actual power consumption in Central Changwon and is expressed 2.9% difference compared to that in Masan district. Therefore, the power consumption prediction for each school using the power consumption estimation equation is possible. (3) The power consumption estimation equation for cooling load is showed 8.0% difference compared to actual power consumption in Central Changwon and is expressed 2.9% compared to that in Masan district. As the power consumption estimation equation for cooling load is expressed difference compared to heating load, it needs to investigate influence for cooling load.

• 전자공학회논문지CI
• /
• 제44권1호
• /
• pp.1-9
• /
• 2007

임베디드 프로세서는 총 에너지소모량 가운데 대략 40% 이상을 캐시에서 소모하고 있으므로 에너지-효율적 고성능 데이터 캐시 구조를 필요로 한다. 본 논문에서는 임베디드 프로세서를 위한 저전력 선인출 데이터캐시 구조를 제안하였다. 제안한 데이터캐시 구조는 선인출장치(prefetching unit)를 포함한 기존 데이터캐시 구조에 태그히스토리 테이블(tag history table)을 구비함으로써 요구인출 및 선인출시 발생하는 태그메모리 병렬탐색 횟수를 감소시켰다. 이와 같은 전략적인 캐시 구조는 적은 하드웨어 비용으로 병렬탐색을 위한 전력소모를 현저히 줄일 수 있다. 실험을 통하여 제안한 데이터캐시 구조가 기존 선인출 데이터캐시 구조와 동일한 성능을 유지하면서 낮은 전력을 요구함을 확인하였다.

• ETRI Journal
• /
• 제34권5호
• /
• pp.727-733
• /
• 2012

This paper demonstrates a new driving scheme that allows reducing the supply voltage of data drivers for low-power active matrix organic light-emitting diode (AMOLED) displays. The proposed technique drives down the data voltage range by 50%, which subsequently diminishes in the peak power consumption of data drivers at the full white pattern by 75%. Because the gate voltage of a driving thin film transistor covers the same range as a conventional driving scheme by means of a level-shifting scheme, the low-data supply scheme achieves the equivalent dynamic range of OLED currents. The average power consumption of data drivers is reduced by 60% over 24 test images, and power consumption is kept below 25%.

• 한국정보통신설비학회:학술대회논문집
• /
• 한국정보통신설비학회 2009년도 정보통신설비 학술대회
• /
• pp.115-116
• /
• 2009

Home-network gateway always powered on, while network data is not transferred. And the Power consumption of networked electric devices are greatly increased, to support higher speed data transfer. To reduce the power consumption of networked electric devices, some ideas were proposed. Such as ALR, Proxying, Subset-PHY. In this paper we propose a scheme to reduce power consumption of Home-Network Gateway. Proposed Home-network Gateway architecture consumes less than 1W in passive standby mode.