• Journal of Audiology & Otology
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• v.23 no.3
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• pp.145-152
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• 2019

Background and Objectives: The present study aims to investigate whether the cochlear implant electrode array design affects the electrophysiological and psychophysical measures. Subjects and Methods: Eighty five ears were used as data in this retrospective study. They were divided into two groups by the electrode array design: lateral wall type (LW) and perimodiolar type (PM). The electrode site was divided into three regions (basal, medial, apical). The evoked compound action potential (ECAP) threshold, T level, C level, dynamic range (DR), and aided air conduction threshold were measured. Results: The ECAP threshold was lower for the PM than for the LW, and decreased as the electrode site was closer to the apical region. The T level was lower for the PM than for the LW, and was lower on the apical region than on the other regions. The C level on the basal region was lower for the PM than for the LW whereas the C level was lower on the apical region than on the other regions. The DRs on the apical region was greater for the PM than for the LW whereas the DR was narrower on the apical region than on the other regions. The aided air conduction threshold was not different for the electrode design and frequency. Conclusions: The current study would support the advantages of the PM over the LW in that the PM had the lower current level and greater DR, which could result in more localized neural stimulation and reduced power consumption.

• Korean Journal of Audiology
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• v.23 no.3
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• pp.145-152
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• 2019

Background and Objectives: The present study aims to investigate whether the cochlear implant electrode array design affects the electrophysiological and psychophysical measures. Subjects and Methods: Eighty five ears were used as data in this retrospective study. They were divided into two groups by the electrode array design: lateral wall type (LW) and perimodiolar type (PM). The electrode site was divided into three regions (basal, medial, apical). The evoked compound action potential (ECAP) threshold, T level, C level, dynamic range (DR), and aided air conduction threshold were measured. Results: The ECAP threshold was lower for the PM than for the LW, and decreased as the electrode site was closer to the apical region. The T level was lower for the PM than for the LW, and was lower on the apical region than on the other regions. The C level on the basal region was lower for the PM than for the LW whereas the C level was lower on the apical region than on the other regions. The DRs on the apical region was greater for the PM than for the LW whereas the DR was narrower on the apical region than on the other regions. The aided air conduction threshold was not different for the electrode design and frequency. Conclusions: The current study would support the advantages of the PM over the LW in that the PM had the lower current level and greater DR, which could result in more localized neural stimulation and reduced power consumption.

• Journal of the Korean Society of School Health
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• v.11 no.2
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• pp.171-187
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• 1998

In recent years, adolescent issues including smoking, drinking, drug abuse, juvenile delinquency, deviant sexual behavior, mental health problems, high suicide rate, juvenile delinquency and absence without due notice, etc are emerging as serious social problems and the debate on these controversial issues is heating up. The previous studies on adolescent health behavior and social juvenile delinquency such as run-away from home and absence without due notice have been conducted mostly by cause analysis utilizing social demographic factors or biological factors. In other words, the main factors analyzed were demographic and economic factors or parent's educational level, etc, which were the fixed environmental ones that were unable to cause the change in the health behavior. Accordingly, the purpose of this study is to analyze factors which are changeable and fixable among the factors influencing the adolescent's health behavior and misconducts and, eventually influencing factors which can be used as the basis to establish health policies and health promotion program to reduce the health risk behavior and misconducts of adolescents. The study subjects were selected by dividing senior high school student in Seoul by region and through random sampling. The 890 subjects were selected from 10 schools including the preparatory school, vocational schools and institutional schools. The duration of the study was for July 1-5, 1997 for the first survey and the second one, for August 25-September 10. Regarding the analysis method, the SAS program was used. The adoptablity of theoretical model was tested through covariance structural analysis utilizing PC-LISREL 8.12 Program. The major findings of the study are as follows: As a result of establishing the model of factors influencing health behavior and juvenile delinquency, in case of male students as the health behavior self-efficacy, education level of fathers, economic level, self-control and the health interest of parent were higher, students were more likely to practice the health promoting behavior. Juvenile delinquency and health risk behavior were prevalent among those with the less shyness, the lower health behavior self-efficacy, lower self-control, lower self-assertiveness, lower economic level. The self-control was the most powerful factor. In case of female students, those with higher health behavior self-efficacy were more likely to practice the health promoting behavior whereas those with lower health behavior self-efficacy, lower self-control, lower self- assertiveness, less shyness were more likely to practice health risk behavior and juvenile delinquency. In case of prep schools, those with higher health behavior self-efficacy and better perceived health status were more likely to practice the health promoting behavior while those with less shyness, lower health behavior self-efficacy and lower academic achievement were more likely to engage in health risk behavior and juvenile delinquency. In case of vocational schools, as health behavior self-efficacy and economic level were higher, the practice rate of health promoting behavior was higher. As the self-control, shyness, self-assertiveness, health behavior self-efficacy were lower, the rate of health risk behavior and juvenile delinquency were higher. In case of social institutional schools, as, the health behavior self-efficacy, social support and economic level, health interest of parents were higher, the rate of health promoting behavior were higher. As the self-control, shyness, self-assertiveness, health behavior self-efficacy and social support were lower, the rate of health risk behavior and juvenile delinquency were higher. So the health promoting behavior was positively related to the health behavior self-efficacy, health interest of parents, social support, education level of fathers, level of perceived health status, economic level. The health risk behavior and juvenile delinquency were higher with the lower health behavior self-efficacy, self-control and self-assertiveness, lower health locus control, less shyness and loneliness, lower economic level and academic achievement. In conclusion, the health risk behavior and juvenile delinquency can be reduced by enhancing self-control, self-assertiveness, health behavior self-efficacy and social support. According to the final model drawn by connecting health behavior and juvenile delinquency, the reduction of health risk behavior can greatly contribute to decreasing social juvenile delinquency as the process of juvenile delinquency was extended from common behaviors to problem behaviors and further into juvenile delinquency.

• Journal of the Korean Society of School Health
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• v.9 no.2
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• pp.171-184
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• 1996

The purpose of this study was to investigate how much students stress have, how they cope with this stress, differences between problem behaviors and personality changes based on stress, and stress differing levels when coping with the situation either actively or passively The hypotheses were stated as follows. 1. There will be differences between problem behaviors and personality problems based on sex. 2 There will be differences between problem behaviors and personality problems based on grade. 3. There will be differences between problem behaviors and personality problems based on stress level. 4. There will be differences between problem behaviors and personality problems based on a student's ability to cope with stress. 5. Upper level students under lower stress and lower level students under higher stress will have more problems behaviors and more personality problems. 300 male/female high school students throughout the Seoul area were randomly selected. Of the 300 subjects that were sampled, 294 (Male=145, Female=149) actually participated in this study. The Stress Scale developed by Lazarus & Folkman (1984) Problem Behavior Scale, Personality Problem Scale, and Checklist were used and the conclusions are stated as follows. First, male students have more anti-social behavior and higher anti-social tendencies than female students and female students have more self-depreciation than male students. Second, upper level students have more anti-social behavior, self-ego, fabrication, and higher personality problems than lower level students. Third, students having too much stress have more anti-social behavior, self-ego, and fabrication and personality problems than students having less stress. Fourth, students coping with stress actively showed less self-ego and fabrication and less thought disturbance, anti-social tendencies, and self-depreciation than students coping with stress passively. Finally, upper level students under lower stress and lower level students under higher stress have more fabrication behaviors and more thought disturbance and self-depreciation.

• Journal of KIISE:Computer Systems and Theory
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• v.36 no.1
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• pp.26-32
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• 2009

The multi-level storage architecture has been widely adopted in servers and data centers. However, while prefetching has been shown as a crucial technique to exploit sequentiality in accesses common for such systems and hide the increasing relative cost of disk I/O, existing multi-level storage studies have focused mostly on cache replacement strategies. In this paper, we show that prefetching algorithms designed for single-level systems may have their limitations magnified when applied to multi-level systems. Overly conservative prefetching will not be able to effectively use the lower-level cache space, while overly aggressive prefetching will be compounded across levels and generate large amounts of wasted prefetch. We design and implement a hierarchy-aware lower-level prefetching strategy called PMS(Prefetching strategy for Multi-level Storage system) that applicable to any upper level prefetching algorithms. PMS does not require any application hints, a priori knowledge from the application or modification to the va interface. Instead, it monitors the upper-level access patterns as well as the lower-level cache status, and dynamically adjusts the aggressiveness of the lower-level prefetching activities. We evaluated the PMS through extensive simulation studies using a verified multi-level storage simulator, an accurate disk simulator, and access traces with different access patterns. Our results indicate that PMS dynamically controls aggressiveness of lower-level prefetching in reaction to multiple system and workload parameters, improving the overall system performance in all 32 test cases. Working with four well-known existing prefetching algorithms adopted in real systems, PMS obtains an improvement of up to 35% for the average request response time, with an average improvement of 16.56% over all cases.

• Journal of the Korean Society for Railway
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• v.11 no.6
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• pp.581-587
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• 2008

This paper presents a railway network design problem (RNDP), which can be formulated as a bi-level program. In bi-level program upper level program is to minimize total travel cost including the construction cost of the railway facilities, whilst lower one describes the railway route choice behavior of passengers. We also propose a heuristic method for solving the program because it is a kind of NP-hard problem. From two numerical railway examples, we confirm that the RNDP and its algorithm produce a reasonable solution and that it is applicable to real world.

• Korean Journal of Rural Living Science
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• v.6 no.1
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• pp.73-84
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• 1995

The objective of this thesis is to analyse empirically the economic resource problems of the rural poor households. Data from 444 rural sample households in four provinces, divided into two subgroups, the poor and the non-poor households, were analysed and compared. The owned arable land size, level of agricultural and non-agricultural income, assets, debts and the sufficiency of living expenses of the poor households were measured and compared with those of non-poor households respectively. The significant findings and drawn conclusions are as follows : The rural poor households 1. tends to show smaller family size, older age and lower level of education of homemakers than the non-poor households, that might work as constraints to income sources and quality. 2. has not only small arable lands and agricultural income but also even smaller cash income, less than 50% of total income, with 27% of self-product consumption and depends more on non-agricultural income than the non-poor households. Such weakness of income structure might cause and increase the income instability of the rural poor households. 3. reveals significantly different level and components of assets from the non-poor households lower level of assets, less amounts of but more load of debt due to lower solvency that comes from low level of income and assets, higher debts for consumption and lower accessibility to credit. All these socio-demographic and economic characteristics of the rural poor households might have compound effects on the economic problems of the poor households and make vicious circle of poor.

• Journal of Nutrition and Health
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• v.22 no.1
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• pp.9-22
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• 1989

The effect of different levels of Zn (0, 30, 300ppm) and protein(7, 20, 40%) in the diet upon lipid metabolism was investigated in Sprague-Dawley male rats weighting 180.54$\pm$29.08g(n=450 fed one of nine diets in a 3$\times$3 factorial design for 5 weeks. The reults obtained were summarized as following. 1) Total lipid contents in serum and liver were tended to be lower in LZn group than CZn and Hzn groups. Those of LP group were higher than CP and HP groups. 2) HDL-cholesterol and total cholesterol contents in serum were significantly affected by dietary Zinc level and were increased as dietary Zinc level increase. 3) Total cholesterol in liver and muscle were tended to be decrease as dietary Zinc level increase. Those in LP group were higher than CP and HP groups. 4) Zinc contents in plasma, liver, muscle and testis were tended to be lower in LZn group than CZn and HZn groups. 5) Protein contents in plasma and liver lower in LZn group than CZn and HZn groups when dietary protein level was 7% and 20%. Those in LP group were lower than those in CP and HP groups. 6) Cu contents in plasma, liver, muscle and testis were tended to be decreased as dietary Zinc level increase.

• International Journal of Advanced Culture Technology
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• v.10 no.3
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• pp.226-236
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• 2022

We compared and analyzed the changes in students' science grades and their effects on science grades by level (upper, middle, and lower) according to non-face-to-face and face-to-face teaching-learning. 66 students from A Middle School in Gyeongsangnam-do were selected for the study. As a result of analyzing the change in science grades according to the teaching-learning type, the average score of science grades by non-face-to-face teaching-learning was lower than the corresponding score of science grades of face-to-face teaching-learning. As a result of comparing the level of understanding of learning content according to the evaluation type (paper-written, study-paper) in non-face-to-face and face-to-face teaching-learning, the average scores of science grades by paper-written and study-paper evaluations in non-face-to-face teaching-learning were significantly low. In addition, as a result of comparing the effect on science grades by level according to the teaching-learning type, the average score of science grades of lower-ranked students in non-face-to-face teaching-learning was relatively low.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.5
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• pp.713-720
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• 2002

A study was designed to determine the effects on broiler performance of two levels of antioxidant (ethoxyquin) in poultry rations containing two levels of oxidized and non-oxidized soybean oil. One hundred and eighty, day old broiler chicks were randomly divided into six experimental groups comprising thirty chicks on each treatment. Six experimental rations having 2% nonoxidized soybean oil, 2% and 3% oxidized soybean oil, all three supplemented with normal (125 g/t) or higher (175 g/t) level of ethoxyquin, were formulated for both starter (0-28 days) and finisher (29-42 days) phases. These rations were randomly fed to six experimental groups having 30 birds on each ration and three replicates on each treatment. Weight gain and feed conversion ratio (FCR) of chicks fed 2% non-oxidized and 2% oxidized soybean oil were statistically non-significant. Weight gain in groups fed 3% oxidized oil was significantly lower than non-oxidized group while FCR was significantly lower than both groups. Weight gain in the higher level ethoxyquin group was significantly better than lower level, while feed intake and FCR were statistically non-significant in both levels of ethoxyquin. Acid and Thiobarbituric Acid (TBA) values in the three groups differed significantly with the lower in non-oxidized group and highest in the 3% oxidized group. Higher level of ethoxyquin significantly lower acid and TBA values compared to lower level of ethoxyquin. Thus it can be concluded that oxidation of oil reduces its feeding value and that the addition of ethoxyquin is beneficial.