• Journal of Information Technology Applications and Management
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• v.20 no.3_spc
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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.

• Journal of IKEEE
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• v.16 no.3
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• pp.203-210
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• 2012

Since the non-overlapping gate driver used in conventional DC-DC boost converters generates fixed dead-times, the converters suffer from the body-diode conduction loss or the charge-sharing loss. To reduce the efficiency degradation due to these losses, this paper presents a PWM DC-DC boost converter with adaptive dead-time control. The proposed DC-DC boost converter delivering 3.3V output from a 2.5V input is designed with CMOS $0.3{\mu}m$ technology. It operates at 500kHz and has a maximum power efficiency of 97.3%.

• Journal of the Korea Computer Industry Society
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• v.6 no.5
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• pp.741-748
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• 2005

Power saving module which is consisted of ferroelectric ceramic capacitor and time delay switching circuit was installed into electronic ballast in order to enhance energy efficacy and extend life time of fluorescent lamp. The impedance matching of negative resistance characteristics of F/L was optimized with the characteristics of ferroelectric ceramics capacitor to increase the light efficiency of the electronic ballast. The high efficiency of the electronic ballast was achieved by minimizing wasted power at the filament of F/L during the lighting by using the switching function of time delay circuit from preheating mode to non-preheating mode. The life time of F/L was also extended by eliminating the reverse electromotive force using time delay circuits to minimize the impacts to the filament of F/L from unwanted high voltage peaks during light-up period. As the results, the electronic ballast with the first grade energy efficiency was developed using ferroelectric ceramics and time delay module.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.4
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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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• v.10 no.11
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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.

• Journal of the Korean Society of Radiology
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• v.17 no.6
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• pp.939-945
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• 2023

This study analyzes the 'performance efficiency' of AI-based reading assistance systems in the field of radiology by measuring their 'time behavior' properties. Due to the increase in medical images and the limited number of radiologists, the adoption of AI-based solutions is escalating, stimulating a multitude of studies in this area. Contrary to the majority of past research which centered on AI's diagnostic precision, this study underlines the significance of time behavior. Using 50 chest X-ray PA images, the system processed images in an average of 15.24 seconds, demonstrating high consistency and reliability, which is on par with leading global AI platforms, suggesting the potential for significant improvements in radiology workflow efficiency. We expect AI technology to play a large role in the field of radiology and help improve overall healthcare quality and efficiency.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.4
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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.

• Journal of the Korea Society of Computer and Information
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• v.17 no.8
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• pp.1-10
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• 2012

This paper proposes design space exploration methodology of many-core processors including multimedia specific instructions to support high-performance and low power ultrasound imaging for portable devices. To explore the impact of multimedia instructions, we compare programs using multimedia instructions and baseline programs with a same many-core processor in terms of execution time, energy efficiency, and area efficiency. Experimental results using a $256{\times}256$ ultrasound image indicate that programs using multimedia instructions achieve 3.16 times of execution time, 8.13 times of energy efficiency, and 3.16 times of area efficiency over the baseline programs, respectively. Likewise, programs using multimedia instructions outperform the baseline programs using a $240{\times}320$ image (2.16 times of execution time, 4.04 times of energy efficiency, 2.16 times of area efficiency) as well as using a $240{\times}400$ image (2.25 times of execution time, 4.34 times of energy efficiency, 2.25 times of area efficiency). In addition, we explore optimal PE architecture of many-core processors including multimedia instructions by varying the number of PEs and memory size.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.31 no.7
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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%.

• Journal of IKEEE
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• v.22 no.3
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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.