• Journal of Internet Computing and Services
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• v.18 no.1
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• pp.121-129
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• 2017

Demand forecasting is one of the most critical tasks in defense logistics, because the failure of the task can bring about a huge waste of budget. Up to date, ROK-MND(Republic of Korea - Ministry of National Defense) has analyzed past component consumption data with time-series techniques to predict each component's demand. However, the accuracy of the prediction still needs to be improved. In our study, we attempted to find consumption pattern using data mining techniques. We gathered an 18,476 component consumption data first, and then derived diverse features to utilize them in identification of demanding patterns in the consumption data. The results show that our approach improves demand forecasting with higher accuracy.

• Journal of Sensor Science and Technology
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• v.29 no.1
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• pp.68-73
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• 2020

This paper proposes an asynchronous circuit design methodology using a new Single Gate Sleep Convention Logic (SG-SCL) with advantages such as low area overhead, low power consumption compared with the conventional null convention logic (NCL) methodologies. The delay-insensitive NCL asynchronous circuits consist of dual-rail structures using {DATA0, DATA1, NULL} encoding which carry a significant area overhead by comparison with single-rail structures. The area overhead can lead to high power consumption. In this paper, the proposed single gate SCL deploys a power gating structure for a new {DATA, SLEEP} encoding to achieve low area overhead and low power consumption maintaining high performance during DATA cycle. In this paper, the proposed methodology has been evaluated by a liquid state machine (LSM) for pattern and digit recognition using FPGA and a 0.18 ㎛ CMOS technology with a supply voltage of 1.8 V. the LSM is a neural network (NN) algorithm similar to a spiking neural network (SNN). The experimental results show that the proposed SG-SCL LSM reduced power consumption by 10% compared to the conventional LSM.

• Journal of the Korean Solar Energy Society
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• v.30 no.6
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• pp.44-49
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• 2010

The purpose of this study is to analyze the situation of energy consumption and its characteristics in large scale store. The related survey is carried out in large scale store to investigate the energy consumption and energy use trend of heating, cooling, hot water, lighting, ventilation, equipments and others. The area of large scale discount store is about $65000m^2$, located in Daejeon. For Annual Energy Analysis of building, We surveyed used energy for 1 year and simulated using a building energy simulation(TRNSYS 16). The results of this study are as follows. 1)The amount of annual total energy consumption are 18615.244MWh/yr(286.4KWh/$m^2yr$), The rate of heating, cooling and base energy(for hot water, lighting, ventilation, equipments, cooking and others) is 3054MWh/yr(47kWh/$m^2yr$), 5660.09MWh/yr(87.08kWh/$m^2yr$), 9900.47MWh/yr(152.31KWh/$m^2yr$) respectively. The total used energy is higher than others building in Korea. Especially, The energy consumption of large scale store is very depends on operating period and pattern such as space temperature, occupancy, lighting system, equipments operating schedule and etc.

• Journal of the Korean Society of Food Culture
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• v.11 no.5
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• pp.643-649
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• 1996

This study was performed to investigate the adequacy of dietary fat and protein intakes among female college students. Daily intakes of energy, fat, protein, major amino acids and other nutrients were measured in 52 female college students. Daily energy intake was 75.8% of the recommended intake. Fat and protein consist 19.2% and 16.7% of the total calorie, respectively. The average protein consumption per day was 105% of the recommended intake. Essential amino acids intakes were more than the recommended amounts which appears in the 6th edition of Recommended Dietary Allowances for Koreans. However, when the intake of each essential amino acid was compared to the recommended amino acid requirement pattern, these subjects did not meet the estimated requirements. There was a highly significant correlation between daily protein intake and lipid intake implying the major sources of protein in the diet were also major sources of fat. Daily intakes of dietary fiber, vitamin C, iron, and phosphorous were above the recommended levels of intake. However, blood hemoglobin concentration was marginal indicating dietary iron consumption is not a good marker for iron status. Also, calcium intake was only 63.5% of the recommended intake. Therefore, these results imply that main problems for these subjects are low energy consumption, low calcium intake, and the quality of protein. However, as opposed to the hypothesis, the main energy sources were not the food items high in saturated fats such as instant foods, which should be emphasized further.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.1
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• pp.97-115
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• 2022

Smart power grid is a user friendly system that transforms the traditional electric grid to the one that operates in a co-operative and reliable manner. Demand Response (DR) is one of the important components of the smart grid. The DR programs enable the end user participation by which they can communicate with the electricity service provider and shape their daily energy consumption patterns and reduce their consumption costs. The increasing demands of electricity owing to growing population stresses the need for optimal usage of electricity and also to look out alternative and cheap renewable sources of electricity. The solar and wind energy are the promising sources of alternative energy at present because of renewable nature and low cost implementation. The proposed work models a smart home with renewable energy units. The random nature of the renewable sources like wind and solar energy brings an uncertainty to the model developed. A stochastic dual descent optimization method is used to bring optimality to the developed model. The proposed work is validated using the simulation results. From the results it is concluded that proposed work brings a balanced usage of the grid power and the renewable energy units. The work also optimizes the daily consumption pattern thereby reducing the consumption cost for the end users of electricity.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.5
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• pp.295-303
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• 2022

This study investigates the impact of globalization, coal consumption, and economic growth on CO₂ emissions in Malaysia by applying the Kuznets Environmental Curve model. The study employed the Autoregressive Distributed Lag modeling technique on time series data over the period of 1970-2018 to determine the short and long-run relationship between CO₂ emissions and a number of variables, including globalization, coal consumption, and economic growth. The results show that globalization increase CO₂ emissions in both the short and long run in Malaysia. Furthermore, the results reveal that economic growth and coal consumption degrade the environmental quality by accelerating the CO₂ emissions in the short-run and long run. As a result, the findings validate the Kuznets Environmental Curve hypothesis of an inverted U-shaped relationship between economic growth and CO₂ emissions in the long run for Malaysia. The findings of this study suggest that higher globalization levels and usage of coal consumption degrade the environmental quality in Malaysia. The findings also indicate the effect of economic growth on environmental degradation is positive at the initial stage but improves after the economy achieves a threshold level of income per capita in the economic development process with an inverted U-shaped pattern in the long run.

• Journal of Korea Trade
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• v.27 no.1
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• pp.119-138
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• 2023

Purpose - This research is to empirically explore the differences in apparel consumption among male and female teenagers and college students in Korea and China. By conducting a survey to understand customers' needs and behaviors, fashion businesses will be able to improve their customer satisfaction and avoid redundancy, inventory, and the waste of resources, effort and money. Design/methodology - The research design considers the consumption patterns of male and female high school and college students in Korea and China. To analyze the data, the study employs decision trees, a type of machine learning algorithm. A decision tree model was developed to examine the relationship between the explanatory and response variables, which can be either quantitative or qualitative in nature. Findings - The main findings of this study indicate that there are differences in shopping behavior among different customer segments. The results show that men have a simpler shopping behavior compared to women. Additionally, cultural factors and the difference in fashion needs between students and non-students have a significant impact on the shopping choices of Chinese and Korean individuals. Originality/value - Existing studies often assume that the shopping behavior of high school and university students is similar and that there are no significant differences in clothing purchases between men and women across countries. The results provide valuable insights into the unique shopping behavior of different customer segments, and can inform fashion businesses in their efforts to meet the needs of their customers.

• Journal of the Korean Society of Food Culture
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• v.13 no.3
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• pp.227-239
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• 1998

The purpose of this stud was to investigate the degree of recognition as well as the consumption pattern of convenience food products, and related factors among 700 mixed Korean college students using written questionnaire. Students of Seoul region showed the significantly lowest rate of recognition at 36.7%. Results also showed that lifestyles have a significant effect on the degree of recognition of convenience foods. The consumption patterns of convenience foods goes as follows: used frequently-18.2%, once in awhile-73.9%, doesn't use-7.9%. The higher the recognition rate, the higher the consumption rate for convenience foods. When compared in terms of residence, students living at home used more refrigerated foods compared to students living outside of the home. Among the total students living outside of the home, students living on their own scored highest of convenience food consumption. In the case of female students living outside the home, respondents living alone and in dormitories scored the highest. Female students living in dormitories were mainly using refrigerated and canned foods, while those living alone consumed more kimbap and 'sa-bal-myun' in convenience stores. Korean college students mainly consumed frozen food, retort food, and kimbap in convenience stores. The college student that believes that 'You eat to satisfy hunger' significantly used more convenience food while those that marked 'maintain health' consumed the lowest showing a great difference between groups. Results showed that the lower the food habit score, the higher the usage score of convenience foods. The food habit score had a negative correlation with the usage of frozen foods, instant food, and convenience store food. When compared individually, packaged 'ramen' and 'sa-bal-myun' scored the highest points of usage. Frozen fried rice and pre-packaged rice scored the lowest points indicating Korean college students do not consider rice a convenience food. Convenience food consumed in convenience stores ranked the highest among places of consumption, compared to places like home or outdoors; showing that convenience foods were used by people with limited time constraints.

• Journal of Preventive Medicine and Public Health
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• v.31 no.4 s.63
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• pp.604-615
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• 1998

Although previous studies revealed the association of physical activity with mortality rate, it is unclear whether there is a linear trend between physical activity and mortality rate. In this study, the association of physical activity with the risk of all-cause mortality was analysed using Cox's proportional hazard model for a cohort of 14,204 healthy Korean men aged 40-59 years followed up for 4 years(Jan. 1993-Dec. 1996). Physical activity and other life style were surveyed by a postal questionnaire in December 1992. Total of 14,204 subjects were grouped into quartiles by physical activity. Using death certificate data, 123 deaths were identified. The second most active quartile had a lowest mortality .ate with relative risk of 0.44(95% C.I. : 0.23-0.84) compared with most sedentary quartile, showing a J-shape pattern of physical activity-mortality curve. By examining the difference in proportion of cause of the death between most active quartile and the other quartiles, there was no significant difference of proportional mortality from cardiovascular deaths, cerebrovascular deaths or deaths from trauma. The covariates were stratified into two group between which the trend of RR was compared to test the effect modification. There was no remarkable effect modification by alcohol intake, smoking, body mass index, calorie consumption, percent fat consumption. In conclusion, moderate activity was found to have more protective effect on all-cause mortality than vigorous activity and that the J-shape pattern of physical activity-mortality curve was not due to the difference of mortality pattern or effect modification by alcohol intake, smoking, body mass index, calorie consumption and percent fat consumption.

• International Journal of Air-Conditioning and Refrigeration
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• v.15 no.3
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• pp.108-113
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• 2007

The performance of a solar water heater incorporating evacuated tubes was evaluated using a transient simulation program, TRNSYS. Simulations were performed for $60^{\circ}C$ of hot water load temperature and for 280 liter of daily hot water volumes and three 400 liter of storage tank volumes. Three patterns of daily hot water consumption profile were used in the present study (morning, lunch and evening). The results show that the increase in solar fraction depends on the load profile, as well as the collector efficiency coefficient. Hot water draw profile has a large effect on the performance of the SDHWS, the morning load profile has the highest solar fraction. The annual solar fraction of the system, at the weather conditions of Jinju is approximately 84% at lunch load pattern, the 280 kg of load volume, 400 kg of tank volume and the $60^{\circ}C$ of load temperature.