• Journal of Information Technology Applications and Management
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• 제20권3_spc호
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• pp.169-185
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• 2013

In this research, for find out how operations efficiency for ERP systems, after introducing ERP to manufacturing firms with DEA technique. According to research analyzed relative time dependent efficiency, using Time Window Analysis. And for company group and the other firm within the each same Industry, the relative effectiveness of each company group establishment was compared using DEA.

• 전기전자학회논문지
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• 제16권3호
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• pp.203-210
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• 2012

기존의 DC-DC 부스트 변환기에 사용되는 non-overlapping gate driver는 dead-time이 고정되어 있기 때문에 body-diode conduction loss 또는 charge-sharing loss가 발생하는 문제점을 가지고 있다. 이러한 loss에 의한 효율 감소를 줄이기 위해 본 논문에서는 dead-time 적응제어 기능을 갖는 PWM DC-DC 부스트 변환기를 설계하였다. 제안된 DC-DC 부스트 변환기는 CMOS $0.35{\mu}m$ 공정으로 설계되었고, 입력전압 2.5V를 받아서 3.3V의 출력전압으로 승압시킨다. 스위칭 주파수는 500kHz이며, 최대효율은 97.3%이다.

• 한국컴퓨터산업학회논문지
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• 제6권5호
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• pp.741-748
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• 2005

형광램프용 전자식 안정기의 효율개선 및 램프의 수명연장을 위하여 강유전체 커패시터와 시간지연스위칭회로로 구성된 절전모듈을 개발하고 적용하였다. 절전모듈에 사용된 강유전체 세라믹스를 이용하여 형광램프의 부저항특성과 최적화를 시키고, 시간지연회로를 통하여 점등초기 예열형에서 비예열형으로 스위칭시켜 점등 중 필라멘트에서 소비되는 전력을 제거함으로써 약 2W의 소비전력을 감소시켜 효율개선을 실현하였으며, 역기전력 제거기능을 통하여 점등 초기 형광램프 필라멘트에 가해지는 충격을 최소화함으로써 형광램프의 수명을 연장시켰다.

• 상하수도학회지
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• 제18권4호
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• pp.470-479
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• 2004

The experimental conditions and relationships between parameters such as organic matter, aeration volume, aeration time, and precipitation time for the effective treatment of domestic wastewater were investigated. With the batch systems, the adsorption amount of unit microbe was measured with the change of MLSS concentration, precipitation time, and aeration amount. Theoretical adsorption amount of microbes was then numerically formulated by use of a SPSS multiple analysis as follows: $$Y=-0.0106(X_1)+0.07310(X_2)+42.705(X_3)+62.700$$ In this study, the amount of organisms to be removed in the range of MLSS concentration 2,000~4,500 mg/l were examined. In order to investigate the optimal condition of nitrification, the upper water in the biosorption stage was used as the initial experiment water. The results showed that the C/N ratio was 1.5 and the reaction time for the optimal nitrification was 1.5 hr. When the adsorption efficiency for microbe biosorption was 66%, the optimum denitrification efficiency was 83.3%. When the optimum parameters obtained from the batch experiment were applied to the lab-scale operation, the total retention time from the flow-in to flow-out was 10 hours and the removal efficiency was 93.8% for $COD_{cr}$ and 80.9% for TN. For the full-scale operation, the total retention time was 9.0 hours and the removal efficiency was 94.4% for BOD, 89.6% for $COD_{cr}$, 88.0% for TN, and 86.2% for TP.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권11호
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• pp.5476-5496
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• 2016

Energy efficiency of resource-constrained wireless sensor networks is critical in applications such as real-time monitoring/surveillance. To improve the energy efficiency and reduce the energy consumption, the time series data can be compressed before transmission. However, most of the compression algorithms for time series data were developed only for single variate scenarios, while in practice there are often multiple sensor nodes in one application and the collected data is actually multivariate time series. In this paper, we propose to compress the time series data by the Lasso (least absolute shrinkage and selection operator) approximation. We show that, our approach can be naturally extended for compressing the multivariate time series data. Our extension is novel since it constructs an optimal projection of the original multivariates where the best energy efficiency can be realized. The two algorithms are named by ULasso (Univariate Lasso) and MLasso (Multivariate Lasso), for which we also provide practical guidance for parameter selection. Finally, empirically evaluation is implemented with several publicly available real-world data sets from different application domains. We quantify the algorithm performance by measuring the approximation error, compression ratio, and computation complexity. The results show that ULasso and MLasso are superior to or at least equivalent to compression performance of LTC and PLAMlis. Particularly, MLasso can significantly reduce the smooth multivariate time series data, without breaking the major trends and important changes of the sensor network system.

• 한국방사선학회논문지
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• 제17권6호
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• pp.939-945
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• 2023

본 연구는 영상의학 분야에서 인공지능(AI) 기술 기반의 판독 보조 시스템의 'Time Behavior(시간반응성)' 속성을 측정하여 '성능 효율성'을 분석하였다. 의료 영상의 증가와 영상의학 전문의 수의 한계로 인해 인공지능(AI) 기술 기반의 솔루션이 증가하고 있으며, 관련된 연구가 많이 수행되고 있다. 하지만 대부분의 선행 연구가 인공지능의 진단 정확도에 초점을 맞췄다면, 본 연구는 Time Behavior의 중요성을 강조하여 수행하였다. 50개의 흉부 엑스레이 PA 이미지를 사용하여 측정한 결과, 평균 15.24초 만에 영상을 처리하여 높은 일관성과 안정성을 보여주었고, 이 처리 속도는 유명 글로벌 AI 플랫폼과 동등한 수준으로 영상의학과 워크플로우 효율성 부분에 크게 개선될 수 있는 가능성을 제시하였다. 앞으로 인공지능 기술이 영상의학 분야에서 큰 역할을 담당하여, 전반적인 의료 품질 향상과 효율성을 개선하는 데 도움이 될 것으로 기대한다.

• 한국식품영양과학회지
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• 제27권4호
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• pp.668-674
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• 1998

Physico-chemical qualities of pyunyuk depending on the cooking time were evaluated to produce high quality and to reduce labor and processing time. Pork headmeat divided into two parts was cooked for 1~4hrs, trimmed and pressed with 110kg/$\textrm{cm}^2$(gauge pressure) for 3.5hrs at 1$0^{\circ}C$. The contents of general nutrients, yield, texture, color, fatty acid composition, gel structure, and sensory evaluation were observed. Deboning time was very dependent on cooking time. Optimum cooking time observed in this study was 2~2.5hrs for efficiency of deboning and yield. Excess cooking time resulted in low yield and working efficiency. Yield variation depending on the cooking time was 14.3~26.0% and it was reduced by increasing the cooking time. The content of moisture was 53.5~54.8% which was not significantly different by cooking time. The content of crude fat was 14.2~26.0% which was decreased by increasing the cooking time. The contents of crude protein(21.1~26.3%) and mineral(1.4~2.7%) were increased by increasing the cooking time. The color of pyunyuk was significantly different by cooking time(p<0.05). In the texture, hardness and chewiness of the pyunyuk cooked for 2hrs were significantly higher than others processed in this study(p<0.05). However cohesiveness and springiness were not different among pyunyuks. With sensory evaluation, hardness was similar among the pyunyuks cooked over 2hrs. The pyunyuk cooked for 1hr showed higher value in juiciness than the pyunyuk cooked for 3~4hrs(p<0.05). The % of saturated fatty acids was decreased by increasing the cooking time, and gel structure of pyunyuk cooked for 2hrs was the most compact among treaments. In conclusion, 2hrs was proper as a cooking time concerned with working efficiency and physico-chemical quality of pyunpyk.

• 한국컴퓨터정보학회논문지
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• 제17권8호
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• pp.1-10
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• 2012

본 논문에서는 휴대용 초음파 영상의 고성능 및 저전력 처리를 위해 멀티미디어 전용 명령어를 내장한 매니코어의 디자인 공간 탐색 방법론을 제안한다. 이를 위해서 멀티미디어 확장 명령어로 인한 서브워드 병렬처리 방식을 적용한 프로그램과 적용하지 않은 프로그램의 성능을 비교하여 에너지 효율 및 면적효율을 측정하였다. 모의실험 결과, MMX 형태 명령어를 사용한 프로그램은 베이스라인 프로그램 보다 $256{\times}256$ 해상도에서 실행시간은 평균 3.16배, 에너지 효율은 평균 8.13배, 면적 효율은 평균 3.16배의 향상을 보였다. $240{\times}320$ 해상도와 $240{\times}400$ 해상도에서는 각각 실행시간 평균 2.16배, 2.25배, 에너지 효율은 4.04배 4.34배, 면적 효율은 2.16배, 2.25배 향상되었다. 더불어 이러한 MMX 형태 명령어를 포함한 매니코어의 프로세싱 엘리먼트 (Processing Element: PE) 개수 및 메모리 사이즈를 변화시키면서 각 초음파 영상의 해상도별로 최적의 시스템 면적 및 에너지 효율을 보이는 PE 구조를 탐색하였다.

• 대한전기학회논문지
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• 제31권7호
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• pp.25-30
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• 1982

This paper considered the energy saving problem of D.C. motor in arbitrary load condition. We can improve efficiency by maintaining the proper ratio of armature current/field current. First, the condition of maximizing the efficiency was obtained, and then the real time control was implemented by using microprocessors. As a result, the efficiency was improved in spite of constant output. For example, the efficiency at 1/5 load was improved from 56.7% to 80%.

• 전기전자학회논문지
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• 제22권3호
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• pp.862-865
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• 2018

The proposed scheme minimizes the Idle time under the residual energy of the sensor node to adjust the Sleep-Wakeup period and minimize unnecessary energy consumption. It is The proposed scheme minimizes the Idle time under the residual energy of the sensor node to adjust the Sleep-Wakeup period and minimize unnecessary energy consumption. It is an important process to control the Application Packet Framework including the PHY and the MAC layer at each node's Idle time with the Idle time mechanism state before the proposed function is executed. The Current Control Level of the Report Attribute is fixed at one sending / receiving node where power consumption can occur, by changing Sleep-Wakeup time, the low power consumption efficiency was improved while satisfying the transmission requirement of the given delay time constraint.