• The Transactions of the Korean Institute of Electrical Engineers
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• v.37 no.10
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• pp.675-682
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• 1988

An improved algorithm for optimal daily hydrothermal unit commitment is proposed in this paper. Especially, for the purpose of guarantee on the existence of feasible solution all the time, the secondary states as well as the primary state are considered at each step in the procedure of solution by Hybird Dynamic Programming to solve the problem of which solution may not exist due to the increased number of constraints to be taken into account. The computational problem which may be caused in the course of considering secondary policies through whole steps of the period examined is solved by the heuristic judgement in every step taking load variation rates into account. The effectivness of the algorithm has been demonstrated by applying it to a sample power system.

• International Journal of Computer Science & Network Security
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• v.21 no.4
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• pp.272-276
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• 2021

Presently, Online / Offline Users are facing cyber attacks every day. These cyber attacks affect user's performance, resources and various daily activities. Due to this critical situation, attention must be given to prevent such users through cyber attacks. The objective of this research paper is to improve the IDS systems by using machine learning approach to develop a hybrid model which controls the cyber attacks. This Hybrid model uses the available KDD 1999 intrusion detection dataset. In first step, Hybrid Model performs feature optimization by reducing the unimportant features of the dataset through decision tree, support vector machine, genetic algorithm, particle swarm optimization and principal component analysis techniques. In second step, Hybrid Model will find out the minimum number of features to point out accurate detection of cyber attacks. This hybrid model was developed by using machine learning algorithms like PSO, GA and ELM, which trained the system with available data to perform the predictions. The Hybrid Model had an accuracy of 99.94%, which states that it may be highly useful to prevent the users from cyber attacks.

• Proceedings of the KIEE Conference
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• 2006.04a
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• pp.51-53
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• 2006

This paper proposes a portable ECG monitoring system, which integrates uptodate PDA and RF communication technology. The aim of the study is to acquire the subject's biomedical signal without any constraint. It has two types of transmission mode, which are total signal transmission mode and HR(heart rate)/SC(step count) transmission mode. In audition, wireless communication technology uses Zigbee Wireless PAN and can work in low-power mode, which is one of the advantages of ZiBbee communication technology. The developed system is composed of a transmitter and a receiver. The transmitter has three-axial acceleration sensor. ECG amplifier and Zigbee communication controller. In total signal transmission mode, it can send data 50 packets per second whose transmission speed corresponds to 300 ECG samples and 60 acceleration samples. In HR/SG transmission mode, it can calculate heart rate from EEG data with 216 samples per second and step count from acceleration data and send a packet every cardiac cycle. The receiver forwards the received data to PDA, where the data can be stored and displayed. Therefore, the developed device enables to continuous monitoring for Activities of Daily Living(ADL). Also, this method will reduce medical costs in the aged society.

• Journal of Korean Physical Therapy Science
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• v.16 no.1
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• pp.31-39
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• 2009

Background: Community ambulation has been recently recognized as one of the most essential factors of activities of daily living in patients with post-stroke hemiparesis. This study aimed to compare walking velocity and step number in 5 community situations in patients with post-stroke hemiparesis. Methods: Ten chronic stroke patients volunteered for this study. The main variables analyzed were walking speed and step number, and these were measured in 5 different community situations: a physical therapy room, a parking lot, a bank, a crosswalk, and a hospital lobby. The measurements obtained for walking in the physical therapy room were measured using a 10m walk test and were used as baseline data for comparison with each option. The ambulation distance was set at 300m for the parking lot and the bank and 150m for the crosswalk and hospital lobby. For data analysis, walking speed and step number were standardized with the distance options of each ambulation. Results: Compared to the walking speed in the physical therapy room, those in the other situations, except for the parking lot, were significantly different (p<.05). Moreover, there were significant differences in the speeds between the bank and the parking lot and between the parking lot and the crosswalk (p<.05). Compared to the step number in the physical therapy room, those in all situations except for the crosswalk were significantly different (p<.05). Further, there was a significant difference in the step number between the bank and the crosswalk (p<.05). Conclusion: The walking ability of patients with hemiparesis in real environments within a community could be different from that in a physical therapy room. Therefore, the evaluation of walking should be performed in a variety of community situations.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.11
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• pp.1427-1435
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• 2010

The present study was conducted to examine the effect of a stair-stepped feed intake pattern on growth, feed efficiency, and meat quality of Hanwoo steers. Twenty-seven 11-month-old Hanwoo steers were randomly divided into three groups. The control group was fed according to the Korean steer feeding program, and the other two groups were fed according to an alternated feeding schedule of 3-2-4-2 months. During the first three months of the experiment, treatment group 1 (T1) and treatment group 2 (T2) were fed 20% and 30% less than the control group, respectively. For the following two months, the T1 group was fed 20% more than the control group while the T2 group was fed 20% less than the control group. In the third step, T1 and T2 groups were fed 20% and 10% less, respectively, than the control group for four months. In the last two months, T1 and T2 groups were fed 20% more than the control group. After the stair-step feeding trial, steers were fed concentrated feed ad libitum for five months. The altered feed intake pattern did not affect daily body weight gain. However, daily feed intake tended to decrease and growth efficiency tended to increase in the two treatment groups compared to the control group. Altered feed intake also affected blood metabolite levels. The serum glucose and BUN level of the T1 group increased in the first re-fed period compared to the T2 and control groups. The serum cholesterol level of the T2 group decreased in the first restricted-re-fed growth period compared to the T1 and control groups. The serum NEFA levels of the two treatment groups increased from the first restricted period compared to the controls. The serum insulin level of the T2 group increased in the last period compared to the T1 and control groups. Regarding meat yield index, the control group was significantly higher than the T2 group (p<0.05). Regarding meat yield grade, the carcass back fat thickness of the T2 group was significantly higher than the control group (p<0.05). In marbling score, the T1 group was the highest (4.9), followed by the control group (4.1) and the T2 group (4.0). These results indicate that using a stair-stepped growth pattern (T1) can contribute to improvements in growth efficiency and muscle marbling.

• Journal of Korea Water Resources Association
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• v.33 no.1
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• pp.61-72
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• 2000

The purpose of this study is to improve the method of evaluating groundwater recharge by using grid-based soil moisture routing technique. A model which predicts temporal variation and spatial distribution of soil moisture on a daily time step was developed. The model uses ASCII-formatted map data supported by the irregular gridded map of the GRASS(Geographic Resources Analysis Support System)-GIS and can generate daily and monthly spatial distribution map of surface runoff, soil moisture content, evapotranspiration within the watershed. The model was applied to Ipyunggyo watershed($75.6\;\textrm{km}^2$) located in the upstream of Bocheongchun watershed. Seven maps; DEM(Digital Elevation Mode]), stream, flow path, soil, land use, Thiessen network and free groundwater level, were used for input data. Predicted streamflows resulting from two years (l995, 1996) daily data were compared with the observed values at the watershed outlet. The results of temporal variations and spatial distributions of soil moisture are presented by using GRASS GIS. As a final result, the monthly predicted groundwater recharge was presented.sented.

• Korean Journal of Psychosomatic Medicine
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• v.5 no.1
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• pp.97-107
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• 1997

As a preliminary step to develop the Daily stress Inventory(DSI) for assessing minor stressors frequently experienced in everyday lift. We examined the reliability and validity of the DSI. The Daily Stress Inventory(DSI), the Beck Depression Inventory(BDI), the State-Trait Anxiety Inventory(STAI), the Social Readjustment Rating Scale(SRRS) and the Minnesota Multiphasic Personality Inventory(MMPI) were administered to 111 college students. Compared with the weekly DSI Event, Impact and I/E ratio scores of the American college students, the weekly event and I/E ratio scores of the Korean college students were significantly higher but weekly Impact score was lower. The internal consistency reliability of the DSI as computed by Cronbach alpha was .98. The DSI I/E ratio scores were significantly correlated with the scores of State Anxiety$({\gamma}=.27)$ and Trait Anxiety${\gamma}=.24)$, but not with BDI scores. And the SSRS scores were not significantly correlated to the DSI Event or Impact and In ratio scores. Significant correlations were revealed between the DSI Impact scores and the Sc and Ma scales of the MMPI. And the correlation between the DSI I/E ratio scores and the L, D, Hy, Pd and Pa scales of the MMPI was also significant. But no significant correlation was found between the DSI Event scores and all the scales of the MMPI. This study suggests that the DSI can be a reliable and valid tool to assess the minor stress frequently experienced in everyday life future study should be directed to obtain normative data based on more varied and larger population. Especially gathering additional evidences for the validity of the DSI using other minor stressor scale will be required.

• Journal of the Korean Dietetic Association
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• v.12 no.3
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• pp.277-288
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• 2006

The purpose of this study was to assess the energy expenditure and investigate the relationship between related variables of 57 dieticians in Youngdong-area. The average daily number of steps was found to be 9358.0$\pm$2714.3 steps/day on weekdays and 7862.9$\pm$2504.9 steps/day during weekends. Hourly step rates on weekdays and weekends came to 570.6$\pm$249.8 steps/hr and 564.0$\pm$224.8 steps/hr, respectively. Activity coefficient of subjects was higher on weekdays (1.56) than weekends (1.51, p<0.05). Resting energy expenditure estimated by the Harris-Benedict formula, WHO/NAO/FAO formula as well as formulas based on body surface area and DRIs (Dietary Reference Intake for Koreans) were calculated to be 1333.7$\pm$89.5kcal/day, 1351.0$\pm$123.3kcal/day, 1388.5$\pm$100.3kcal/day and 1295.9$\pm$90.8kcal/day, respectively. Using these resting energy expenditures and the activity coefficients, daily energy expenditures were calculated to be from 2039.7kcal/day to 2183.5kcal/day on weekdays and from 2016.1kcal/day to 2159.2kcal/day on weekends. Meanwhile energy intakes of subjects on weekdays and weekends were 1594.7$\pm$698.3kcal and 2152.9$\pm$768.0kcal, respectively. The activity coefficient (1.49) of dieticians who managed less than 500 meals per day was significantly lower than that of dieticians who served more than 500 meals per day. Dieticians of schools located in rural areas had higher activity coefficient (1.59) than those of schools located in urban or island settings. These results suggest that work analysis and development of management strategies are necessary to improve dieticians' productivity.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.2
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• pp.655-660
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• 2016

Smoking is accountable for the fatality of a substantial number of persons and increases the likelihood of cancer and cardiovascular diseases. Although data have shown high prevalence rates of cigarette smoking in Saudi Arabia, relatively little is known about the broader scope. The objectives of this study were to investigate socio-demographic factors, patterns of use and cessation behavior associated with smoking in Saudi Arabia (KSA). The study utilized a cross-sectional, multi-step design of sampling. Residents (N=1,497; aged 15 years and older) were recruited from seven administrative areas in Southwest Saudi Arabia. A pretested questionnaire was utilized to obtain data on participant cigarette smoking, including their daily use, age, education, income, marital status and employment status. The current study is the first of its kind to gather data cessation behavior of Saudi subjects. With the exception of 1.5% females, all the respondents were male. The majority of the respondents were married, had a university level of education, were employed, and were younger than 34 years old. The same trends were also observed among smokers' samples. The current prevalence of cigarette smoking was 49.2% and 65.7% of smokers had smoking at less than 18 years of age. The mean daily use amongst smokers was 7.98 cigarettes (SD=4.587). More than 50% of the study sample had tried at least once to quit smoking. However, 42% of the smokers participating had never. On the other hand, about 25% of the respondents were willing to consider quitting smoking in the future. Modeling of cigarette smoking suggested that the most significant independent predictors of smoking behavior were geographic area, gender, marital status, education, job and age. Considerable variation in smoking prevalence was noted related with participant sociodemographics. Findings recommend the necessity for control and intervention programs in Saudi community.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.26 no.2
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• pp.61-69
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• 2020

As post-harvest processes of onions are carried by a 20 kg-net package which results in high-cost and low-efficiency, especially, the insufficient drying and physical damage of onions after harvesting leads to a huge second loss in storage, we had developed a low-cost, high-efficiency post-harvest bulk handling machinery system by collecting onions on a farm using ton-bags, drying with forced air circulation, and sorting/packaging. The post-harvest bulk handling machinery system consisted of 6 devices, and this study designed an automatic feed hopper with a feeding rate control device, an inclined belt conveyor with a two-step chute, and an automatic pallet unloading device for feeding onions into the sorting/packing line. This study also analyzed the performance and control of the total system. The device had 1-ton handling capacity, but the operational condition was set to increase the capacity. The three-step filling method of pallet by the velocity control of the inclined belt conveyor was applied in the post-harvest bulk handling machinery system for the prevention of physical damage. If one worker was set to operate the total system, the time required to complete one palletized load was approximately 5 minutes and 5 seconds. The calculated daily handling capacity was approximately 94 tons, when the daily actual working time was 8 hours. When the developed system was applied to the managerial size of 2,000 ton, the processing cost per ton of the system was decreased by 19.5%, compared with the existing 20 kg-net package-based handling. The developed post-harvest bulk handling machinery system would be a good substitute for the rapid decline and aging of rural labor.