• Journal of the Korean Home Economics Association
• /
• v.36 no.12
• /
• pp.201-216
• /
• 1998

This study was conducted to assess the nutrient intake and diet quality of college students in Seoul. Dietary survery data were obtained by 24-hour recall method from 774 students, 553 males and 191 females. Mean daily intake of energy was 2,480kcal with 56.4% of energy intake from carbohydrate, 14.6% from protein, and 25.5% from fat. Percentage of fat was higher than mean values of National Nutrition Survey(NNS), adults in rural area or younger students in previous studies. Mean daily intakes of calcium and vitamin A did not meet RDA levels in both sexes and intake of iron in females was insufficient to meet RDA level. The percentage of animal food to total food intake was 25% and consumption of meat, beverage and milk group was higher than those of National Nutrition Survey(NNS). When the consumption of 5 major food groups(grain, meat, milk, fruit, vegetable) were evaluated, 22% of students consumed all 5 groups and 47% consumed 4 groups, which show more balanced food group intake than adults in rural area. Food groups which were omitted frequently were milk and fruit. These results show that college students in Seoul consume better diet than subjects of National Nutrition Survey(NNS) or adults in rural area. However, high fat intake, low calcium and vitamin A intake and low iron level in women were observed. Majority(78%) of students had at least one food group omitted in their diet. Appropriate nutrition education may help to improve the quality of diet in these students.

• International Journal of Computer Science & Network Security
• /
• v.23 no.8
• /
• pp.121-136
• /
• 2023

Wireless Sensor Networks (WSNs) have many potential applications and unique challenges. Some problems of WSNs are: severe resources' constraints, low reliability and fault tolerant, low throughput, low scalability, low Quality of Service (QoS) and insecure operational environments. One significant solution against mentioned problems is hierarchical and clustering-based multipath routing. But, existent algorithms have many weaknesses such as: high overhead, security vulnerabilities, address-centric, low-scalability, permanent usage of optimal paths and severe resources' consumption. As a result, this paper is proposed an energy-aware, congestion-aware, location-based, data-centric, scalable, hierarchical and clustering-based multipath routing algorithm based on Numerical Taxonomy technique for homogenous WSNs. Finally, performance of the proposed algorithm has been compared with performance of LEACH routing algorithm; results of simulations and statistical-mathematical analysis are showing the proposed algorithm has been improved in terms of parameters like balanced resources' consumption such as energy and bandwidth, throughput, reliability and fault tolerant, accuracy, QoS such as average rate of packet delivery and WSNs' lifetime.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.23 no.5
• /
• pp.596-603
• /
• 2019

A reprogramming operation is necessary to update the software code of the node to change or update the functionality of the deployed node in wireless sensor networks. This paper proposes an optimization algorithm that minimizes the transmission energy of a node for the purpose of reprogramming a node in wireless sensor networks. We also design an algorithm that keeps energy consumption of all nodes balanced in order to maintain the lifetime of the network. In this paper, we propose a Tabu search algorithm with a new neighborhood generation method for minimizing transmission energy and energy consumption in wireless sensor networks with many nodes. The proposed algorithm is designed to obtain optimal results within a reasonable execution time. The performance of the proposed Tabu search algorithm was evaluated in terms of the node's transmission energy, remaining energy, and algorithm execution time. The performance evaluation results showed better performance than the previous methods.

• Proceedings of the KIEE Conference
• /
• 1999.07e
• /
• pp.2423-2425
• /
• 1999

During the last years demands for higher visual comfort, flexibility of the lighting system in new type of office structures, especially intelligent building, and compatibility with work at VDU place increased. At the same time better lighting conditions should be realized by energy-effective system leading to less consumption of energy. In the intelligent building need the now type of lighting control system, also it should be included for a human-sensibility. It is shown that when designing lighting for intelligent building, greater importances should be attached to the creation of a well-balanced luminance distribution in the field and research for the people by the Ergonomics Planning.

• Korean Journal of Community Nutrition
• /
• v.10 no.4
• /
• pp.484-492
• /
• 2005

The purposes of the study were to analyze nutrients of the menus served and to evaluate students' nutrient consumption at school food services. Three middle schools (boys, girls, and co-ed schools) were located in Seoul and Kyunggi Province. A weighed plate method was employed to measure plate wastes and consumption of the menus served. Data was collected for 3 consecutive days at each school. Nutrient analyses for the served and consumed menus were performed using CAN-PRO. On average the students consumed $67\%$ of the menus they were served. By menu category, the students consumed more than $90\%$ of the rice and one-dish foods they were served. Kimchis ($54\%$) and soups/stews ($55\%$) were the menu categories with the lowest consumption rates. The menus served at the boys and coed schools did not meet 1/3 of the recommended daily allowances (RDA) for calcium, iron, and vitamin $B_2$. Due to the plate wastes, the actual consumption of the boys school students did not meet the 1/3 RDA for calories, calcium, iron, vitamin A, vitamin $B_1$ vitamin $B_2$ and niacin. The menus served at the girls school exceeded the 1/3 RDA for all nutrients, but the actual consumption did not meet the 1/3 RDA for calcium, iron, and vitamin $B_2$. During the 3-day periods, the served and consumed menus provided $27\%$ and $24\%$ of energy from fat, which exceeded the recommended proportion of $20\%$. To improve nutrition management at school food services, dietitians should understand factors that influence students' consumption and implement nutrition education programs that emphasize balanced diets.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.18 no.2
• /
• pp.169-176
• /
• 2018

In this paper, we consider duty-cycled wireless sensor networks (WSNs) in which sensor nodes are periodically dormant in order to reduce energy consumption. In such networks, as the duty cycle interval increases, the energy consumption decreases. However, a higher duty cycle interval leads to the increase in the end-to-end (E2E) delay. Many applications of WSNs are delay-sensitive and require packets to be delivered from the sensr nodes to the sink with delay requirements. Most of existing studies focus on only reducing the E2E delay, rather than considering the delay bound requirement, which makes hard to achieve the balanced performance between E2E delay and energy consumption. A few study that considered delay bound requirement require time synchronization between neighboring nodes or a specific distribution of deployed nodes. In order to address limitations of existing works, we propose a duty-cycle scheduling algorithm that aims to achieve low energy consumption, while satisfying the delay requirements. To that end, we first estimate the probability distribution for the E2E delay. Then, by using the obtained distribution we determine the maximal duty cycle interval that still satisfies the delay constraint. Simulation results show that the proposed design can satisfy the given delay bound requirements while achieving low energy consumption.

• Korean Journal of Community Nutrition
• /
• v.15 no.3
• /
• pp.329-341
• /
• 2010

The purpose of this study was to examine vegetable & fruit (V/F) intakes, beliefs and self-efficacy regarding V/F consumption, nutrition knowledge and eating behavior of elementary students. A survey was conducted to the 4th graders (n = 234) at two elementary schools in Guri, Kyunggi-do. About one-fourth of subjects were overweight or obese. Subjects had 4.2 servings of V/F a day, consuming 340.2 g of V/F. Girls consumed significantly more amounts of vegetables than boys (p < 0.05). Girls were more favorable regarding V/F consumption (p < 0.01), and believed more strongly on advantages of having V/F such as “good for skin” constipation prevention (p < 0.001) and cancer prevention (p < 0.05). Boys felt more strongly in disadvantages or barriers of eating V/F, including mother's cooking time constraints (p < 0.01), lack of past experience of eating V/F, and family members' disliking of V/F (p < 0.05). Girls felt more confident in eating V/F (p < 0.05) than boys; they also felt more confident in specific items of "eating fruits/salads instead of cookies/chips for snack" and "eating fruit juice/vegetable juice instead of soda"(p < 0.01). Subjects showed low level of nutrition knowledge, especially in items such as balanced meals, recommended servings of V/F and vitamin deficiency. Compared to boys, girls had more desirable eating behavior such as eating adequate amount of meals (p < 0.001), having a variety of foods, eating fruits daily, and having fatty foods less frequently (p < 0.05). Intakes of Ca and K were quite below the recommended level, while the intakes of protein, Na and vitamin A intake were much above the Dietary Reference Intakes (DRI) for 9-11 old children. Nutrient intakes expressed as %DRI was higher in girls for vitamin A (p < 0.01), energy and riboflavin (p < 0.05). High V/F consumption group (${\geq}5$ servings of V/F a day) compared to the counterparts showed higher self-efficacy and had better eating behaviors. Nutrition education for children should focus on increasing consumption of V/F, by helping them to increase self-efficacy for eating V/F and to recognize the benefits and reduce the barriers of eating V/F, especially in boys. It is also needed to provide nutrition information for balanced meals or increasing V/F consumption, and help the children to adopt desirable eating behavior.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.37B no.12
• /
• pp.1186-1194
• /
• 2012

In order to resolve the energy efficiency in wireless sensor networks, a multihop transmission technique is utilized. However, multihop transmission in wireless sensor networks (WSN) has pros and cons. It reduces total energy consumption, while it may cause a severe decrease in network lifetime. To solve this problem, we suggest the so called strike and bargaining algorithm (SBA). The routing path is determined by wages of nodes. Each node negotiates its wage with their neighbor nodes and determine a reasonable value to reach a optimally balanced point. By analysis and simulations, we show SBA can achieve a near optimal solution.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.26 no.5
• /
• pp.199-205
• /
• 2014

The integration of FC (Fuel Cell) and GSHP (Ground Source Heat Pump) hybrid system could produce a synergistic advantage in thermal and electric way. This study intends to analyse the economical aspect of a FC integrated GSHP hybrid system compared to the conventional system which is consisted with a boiler and a chiller. Based on the hourly simulation, the study indicated that GSHP system and FC+GSHP hybrid system could reduce the energy consumption on a building. The method of the economic assessment has been based on IEA ECBCS Annex 54 Subtask C SPB(Simple Payback) method. The SPB was calculated using the economic balanced year of the alternative system over the conventional (reference) system. The SPB of the alternative systems (GSHP and FC+GSHP) with 50% initial incentive was 4.06 and 26.73 year respectively while the SPB without initial incentive of systems was 10.71 and 57.76 year.

• Journal of Obesity & Metabolic Syndrome
• /
• v.27 no.4
• /
• pp.254-261
• /
• 2018

Background: The most beneficial dietary pattern in managing metabolic syndrome (MetS) in the elderly has not been ascertained. The aim of this study is to classify dietary patterns and to examine associations between dietary pattern, MetS and body composition in elderly Koreans. Methods: This study was conducted among Koreans 65 years or older using data from the Korea National Health and Nutrition Examination Survey in 2009. A total of 1,567 study subjects were included. All statistical analyses were conducted using SPSS version 20.0 and dietary patterns were classified by cluster analysis. Results: There were three dietary patterns derived by cluster analysis in this study. We observed that most South Korean elderly still maintain a traditional dietary pattern. Dietary patterns were classified as balanced (31%), imbalanced (40%), or very imbalanced (30%), with the majority of subjects having an unbalanced diet pattern in which their total energy and nutrient intake was insufficient compared with the Dietary Reference Intake for Koreans. Those in the very imbalanced group had a ratio of macronutrients (carbohydrates:fats:protein) of 81.15:7.18:11.50 and a 54% higher likelihood of having hypertriglyceridemia (P=0.025) compared with those in the balanced group. Conclusion: The current findings indicate that the diets of South Korean elderly are nutritionally imbalanced, including high carbohydrate consumption, which confers a high risk hypertriglyceridemia. These findings highlight the effect of nutritional imbalance in elderly with MetS.