• Journal of Soil and Groundwater Environment
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• v.11 no.5
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• pp.59-66
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• 2006

Optimal method of radon analysis in groundwater was studied using ultra low-level liquid scintillation counter (ULLLSC) which is well known as an analytical instrument for analyzing the alpha and beta radionuclides in environmental materials. Optimization of pulse shape analyzer (PSA) in operating the LSC was performed with $^{241}Am\;and\;^{90}Sr/^{90}Y$ as well as $^{226}Ra$ Also, the chemical quenching of scintillation generation and the color quenching of the generated photon to photomultiplier tubes (PMT) were determined their effects not only to decrease the analytical efficiency but also to change the optimal PSA level and background due to high ion contents of groundwaters. The optimal PSA level was shown in the range of 90 to 110 with less than 5% error. The effects of high ion contents in groundwater for the analytical efficiency show within 10% error from the different ion contents. The chloroform as a quenching agent was used to determine the analytical efficiency with the different amount, showing that the efficiency decreases 20% using the 2% of chloroform.

• Textile Coloration and Finishing
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• v.19 no.2
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• pp.14-23
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• 2007

This research article explores the use of phthalocyanine reactive dye on nylon substrate. The effect of factors such as pH, temperature, liquor ratio and alkali addition on level of dye exhaustion, fixation and total fixation efficiency. Low pH, high temperature and low liquor ratio were found to be suitable conditions for maximum % exhaustion values. The effect of sulphatoethylsulphone(SES) and vinylsulphone(VS) form of the dyes on level of dye fixation was also discussed. The optimized exhaustion (%E), fixation(%F) and total fixation efficiency were determined. Modification of the dyeing process with alkali addition displayed that dye fixation(%) increased by alkali addition. Vinylsulphone(VS) moiety of the dye was found to be superior to. maximum fixation (%F). Appropriate predictable empirical models, relatively a new approach in dyeing processes, were developed incorporating interactions effects of temperature, pH and liquor ratio for predicting % exhaustion, fixation and total fixation efficiency. The significance of the mathematical model developed was ascertained using microsoft excel regression(solver) analysis module. High correlation coefficient was obtained (R2=0.9895 for % exhaustion, R2=0.9932 for fixation, R2=0.9965 for total fixation efficiency) for the model which shows prominent prediction capacity of the model for my conditions. The predictable polynomial equations developed from tile experimental results were thoroughly analyzed by ANOVA (Analysis of Variance) statistical concepts.

• Journal of Navigation and Port Research
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• v.31 no.7
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• pp.605-611
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• 2007

In order to become a mega hub port, major ports all over the world are making every effort to enhance their productivity through efficiency of internal operation. Accordingly, in order to enhance the competitiveness of a container terminal, an automated container terminal is considered as the best alternative. An automated container terminal is using such automated handling equipment as AGV(Automated Guided Vehicles) and ATC(Automated Transfer Crane). The efficient equipment operation plays a critical role in enhancing the productivity of an automated container terminal. In an automated container terminal, the most important equipments are AGV and ATC. Each block of containers with a vertical layout is generally operating two ATCs. The two ATCs can be crossed or not at each block. In the case of operating crossover ATC, it has an advantage of high flexibility that ATC work is possible at both TP(Transfer Point) of each block. But it has also a disadvantage that the yard has to be operated at a low storage level of containers in the terminal yard. Recently, for automated container terminals, which are being prepared for opening in Korea, they plan to use uncrossed twin ATC in order to make the storage level of their yards high at a low cost. Therefore, studies have to be made in order to increase the efficiency of twin ATC system based on the flexibility that the crossover ATC system has. This research aims to suggest an operation strategy to improve efficiency of twin ATC at each storage block in a yard.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.4
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• pp.532-537
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• 2005

Increasing of body weight has been one of the important economic factors in the poultry industry. Insulin-like growth factor (IGF)-I is a polypeptide that serves to regulate muscle development and body growth. Moreover, IGF-I is related to feed efficiency. However, there are few studies regarding the regulatory roles of chicken IGF-I/-II compared with that of mammals. Especially, the Korean Native Ogol Chicken (KNOC) has a lean body growth and its body weight is generally lighter than the broiler chicken. Therefore, this study was conducted to investigate associations among serum IGF-I/-II concentration, feed efficiency, and body growth in KNOC. The body weight and feed intake of KNOC were recorded from 20 to 36 weeks at 2 weeks intervals, and blood was taken every 2 weeks. Serum IGF-I/-II were measured by RIA. Chickens were divided into two groups, high and low serum IGF-I concentration. Generally, feed efficiency and growth performance (body weight and weight gain) in the high serum IGF-I group were higher than those of the low group during the experimental period. In particular, the body weight of the IGF-I high group were significantly different from those of the IGF-I low group at 34 and 36 weeks, respectively (p<0.05). Moreover, body weight, weight gain, and feed efficiency had a significant correlation with serum IGF-I at several weeks (p<0.05 and p<0.01). These results show that IGF-I plays an important role in body growth and suggests a possibility that serum IGF-I could be used as a selection marker for body growth in KNOC.

• Journal of Families and Better Life
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• v.9 no.2
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• pp.155-170
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• 1991

The purpose of the study was to investigate the effects of demographic-socialogical variables.(ie. educational level, duration of marriage, mate selection type, monthly income, number of children and the frequencies of family's jonit-leisure-activity) and efficiency of the interspous communication on marital satisfaction over the family life cycle. The subject were 278 husbands and wives living in Seoul area who had the eldest child attending at elementary school, middle school , high school and university , respectively. The families were categorized to Duvall's family life cycle. Before the main study was conducted from SEP. 27 to OCT. 8. 1990. a pre-test was conducted on 52 subjects form SEP. 20 to SEP.23.1990. The values of Chronbach's α were obtained on the efficiency of the interspouse communication (α =0.885) and marital satisfaction (α=0.939). Data analysis was by Chronbach's α, ANOVA. Pearson's Product Moment Correlation. Path Analysis and Multiple Regression Analysis. The results were as follows; 1) Marital Satisfaction was positively related (1) to demographic-socialogical variables; educational level , monthly income, the frequencies of family's joint-leisure-activity (2) the efficiency of the interspouse communication. 2) Efficiency of the interspouse communication was positively related to the frequencies o family's joint-leisure-activity. 3) The relative importance of independent variables on marital satisfaction over the family life cycle was found to be varied in each stage of life cycle. (1) As for the group who had elementary-school-aged children; efficiency of the interspouse communication (β=0.717.p<.001), joint-leisure-activity frequency (β =0.303.p<.001), monthly income(β=0.202.p<.001), mate selection type(β=0.180.p<.05), (2) As for the group who had middle-school-aged children; efficiency of the interspouse communication (β=0.702.p<.001), (3)As for the group who had high school-aged children; efficiency of the interspouse communication (β=0.488.p<.001), joint-leisure-activity frequency (β=0.368.p<.001), (4)the group who had university-aged children; efficiency of the interspouse communication.(β=0.729.p<.001), monthly income (β=0.164.p<.01). The regression model showed that 55 percent of the marital satisfaction could be account for by demographic-socialogical variables and efficiency of the interspouse communication (R2=0.551)

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.6
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• pp.76-83
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• 2010

Recently, as the current and future emission regulations go stringent, the research of NOx reduction has become a subject of increasing interest and attention in diesel engine. Selective Catalytic Reduction (SCR) is one of the effective technology to reduce NOx emission from diesel engine. Especially, Urea-SCR that uses urea as a reductant is becoming increasingly popular as a cost effective way of reducing NOx emissions from heavy duty vehicles. In this research, we designed urea injector and DCU (Dosing Control Unit) specially developed for controlling the Urea-SCR process onboard vehicles. As passenger and commercial diesel engine experiment, we grasped characteristics of NOx emission and SCR catalyst temperature level in advance. As a result, highest NOx emission level was shown in condition of low engine speed and high load. On the other hand, SCR catalyst temperature was highest at high engine speed and load. On the basis of these result, we conducted the NOx reduction test at steady engine operating conditions using the urea injector and DCU. It was shown that 74% NOx conversion efficiency on the average and 97% NOx conversion efficiency was obtained at high SCR catalyst temperature.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.2
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• pp.18-26
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• 2012

Though electricity consumption amount in industry has been increased gradually, corresponding power supply show symptoms of marginal point. Importance of demand-side management from large-industries has also been raised. This paper deals with induction motor, which is one of representative examples of heavy electricity consumption utilities, to analyze potential technical capability, economic feasibility from consumers' viewpoint and demand-side management feasibility from nation-wide perspective. Nation-wide economic feasibility analysis was done through California test, which has been used as demand-side management evaluation model. This paper also describes limitation of existing high efficiency induction motor in terms of contribution to demand-side management and utilizes premium motor to calculate demand-side management contribution level and economic feasibility evaluation. Likewise, this paper emphasizes the efficiency improvement of induction motor and analyzes how much premium motor related technologies can contribute to demand-side management.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1818-1820
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• 2000

Due to recent technology advances, needs for flat panel displays, plasma display panels(PDPs) whose advantages are simple structure, high resolution, wide viewing angle is increasingly expected to be the first flat panel of large screen, walt hanging TVs. But the luminance and luminous efficiency of color PDP is net up to the level of a CRT. So, New electrode shape which is different from the conventional electrode has to propose to improve the luminance and luminous efficiency. In this paper, we suggested new shaped electrodes. In new shaped electrode, the discharge current was reduced compared with conventional type by reducing the unnecessary diffusion loss near the barrier rib. However, the luminance was nearly the same as conventional type. So, the luminous efficiency improved about 35%.

• Industrial Engineering and Management Systems
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• v.13 no.2
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• pp.210-220
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• 2014

This article describes a 2-in-1 methodology utilizing simulation optimization technique and Data Envelopment Analysis in measuring an accurate efficiency score. Given the high level of stochastic data in real environment, a novel methodology known as Data Collection Budget Allocation-Data Envelopment Analysis (DCBA-DEA) is developed. An example of the method application is shown in banking institutions. In addition to the novel approach presented, this article provides a new insight to the application domain of efficiency measurement as well as the way one conducts efficiency study.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.35 no.6
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• pp.581-593
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• 2022

As energy depletion and environmental pollution problems are intensified, research has been conducted actively on alternative energy sources, an eco-friendly and continuous available energy conversion system. So has been organic solar cells whose efficiency is improved to 18.32%. The photoactive layer inside the solar cell is composed of a donor and a acceptor, and the combination of materials capable of effectively exchanging electrons greatly affects the efficiency of the organic solar cell. Accordingly, various researches have been conducted to improve the efficiency, and the maximum efficiency could be achieved by a solar cell with high carrier generation and low charge recombination characteristics through the introduction of a non-fullerene acceptor and material reconstruction. Organic solar cells are still difficult to commercialize due to their efficiency limitations and light stability, but if a photoactive layer consisting of a donor capable of efficiently absorbing long-wavelength light and an acceptor capable of forming an appropriate energy level is designed, the efficiency of the organic solar cell will reach 20%.