• Title/Summary/Keyword: Energy Management and Control

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Evaluation of a Nutrition Education Program for Elementary School Children (초등학교 고학년 대상 영양교육의 효과 평가)

  • Ahn, Yun;Ko, Seo-Yeon;Kim, Kyung-Won
    • Korean Journal of Community Nutrition
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    • v.14 no.3
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    • pp.266-276
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    • 2009
  • The purpose of this study was to implement and evaluate the nutrition education program for elementary school children Subjects were 5th graders (n = 142) of an elementary school in Seoul, and 138 children completed four sessions of nutrition education during March-April, 2008. One group pretest-posttest design was used to evaluate the program effectiveness. Anthropometric measurements and measurements on nutrition knowledge, eating attitudes and eating behavior were done before and after education. Data were analyzed using paired t-test, t-test and ${\chi}^2-test$. After completing nutrition education, body mass index (from 19.3 to 18.9), fat mass (from 10.9 kg to 10.1 kg), percent body fat (from 25% to 23.3%) of subjects decreased significantly (p < 0.001). Percentages of overweight or obese children were 24.6% at pretest and decreased to 20.3% at posttest, although it did not reach statistical significance. Total score of nutrition knowledge increased significantly from 11.9 (59.5/100) at pretest to 14.7 (73.5/100) at posttest (p < 0.001). After nutrition education, percentages of correct answers increased significantly in 10 knowledge items out of 20 items. These included items such as desirable weight control, energy requirements for boys, food groups, snack, and function of fat and balanced meals (p < 0.001). Total score of eating attitudes increased significantly from 35.1 to 36.9 (p < 0.001). Attitude of applying nutrition knowledge to daily life (p < 0.001), interest toward nutrition and health (p < 0.001), attitude of moderating food intake (p < 0.01), and attitude toward eating habit and future health (p < 0.05) were significantly different between pretest and posttest. Total score of eating behaviors increased significantly from 46.7 (possible score: 20-60) to 49.5 by nutrition education (p < 0.001). Improvement in eight eating behaviors were noticed after nutrition education. These included eating meals slowly, eat protein foods (p < 0.001), eating breakfast, eating meals regularly, eating meals with diverse foods, having dairy foods, eating foods using plant oils (p < 0.01), and having grains (p < 0.05). Subjects evaluated quite positively in attractiveness of program, understanding of program contents, helpfulness of program in improving nutrition knowledge and meal management. Study results show that the nutrition education program was effective in improving nutrition knowledge, eating attitudes and changing eating behaviors of children. This program can be used in nutrition education of children at school or at public health centers.

System Diagnosis and MEMS Driving Circuits Design using Low Power Sensors (저 전력 센서를 이용한 MEMS 회로의 구현과 시스템 효율의 진단)

  • Kim, Tae-Wan;Ko, Soo-Eun;Jabbar, Hamid;Lee, Jong-Min;Choi, Sung-Soo;Lee, Jang-Ho;Jeong, Tai-Kyeong
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.45 no.1
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    • pp.41-49
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    • 2008
  • Many machineries and equipments are being changing to various and complicated by development of recent technology and arrival of convergence age in distant future. These various and complicate equipments need more precise outcomes and low-power consumption sensors to get close and exact results. In this paper, we proposed fault tolerance and feedback theorem for sensor network and MEMS circuit which has a benefit of energy efficiency through wireless sensor network. The system is provided with independent sensor communication if possible as unused action, using idle condition of system and is proposed the least number of circuits. These technologies compared system efficiency after examining product of each Moving Distance by developed sensor which gives effects to execution of system witch is reduced things like control of management side and requirement for hardware, time, and interaction problems. This system is designed for practical application; however, it can be applied to a normal life and production environment such as "Ubiquitous City", "Factory Automata ion Process", and "Real-time Operating System", etc.

Relationship between dairy products, fish and shellfish intake and metabolic syndrome risk factors in prediabetes: based on the sixth Korea National Health and Nutrition Examination Survey (KNHANES VI-3) 2015 (전당뇨병 대상자의 유제품 및 어패류 섭취와 대사증후군 위험인자와의 관련성 연구 : 2015년 제 6기 국민건강영양조사 자료를 바탕으로)

  • Park, Jeong Seop;Kim, Kyoung Yun
    • Journal of Nutrition and Health
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    • v.50 no.5
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    • pp.447-459
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    • 2017
  • Purpose: Metabolic Syndrome (MetS) is defined as a cluster of inter-connected metabolic disorders involving the glucose metabolism, dyslipidaemia, high blood pressure, and abdominal obesity. The worldwide prevalence has been rapidly increasing to approximately 20~25%, and the prevalence in Korea as of 2012 was reported to be 31.3%. The association of MetS with various diseases needs to be analyzed by conducting an investigation of frequently consumed foods, such as dairy products, fish, and shellfish in prediabetic subjects. Methods: The dietary intake of subjects who met the criteria of the study from January to December 2015 was assessed using the 24-hour recall method. After adjusting the age, sex, BMI, and total energy intake, which are confounding factors that may affect the dietary intake of the subjects, the associations of dairy products, fish, and shellfish intake with the MetS risk factors was analyzed. Results: In prediabetes, the intake of subjects who consumed more than the dairy products median (187.0 g) and the elevation risk of TC [OR, 2.369; 95% CI, 1.057 to 5.312] showed a significant positive association. In prediabetes, the intake of subjects who consumed more than the fish and shellfish median (44.0 g) and the elevation risk of BP showed a significantly weak negative association [OR, 0.073; 95% CI, 0.010 to 0.520]. The probability that the blood LDL cholesterol was ${\geq}100mg/dL$ decreased 0.397 times [95% CI, 0.189 to 0.832]. Conclusion: To control the metabolic risk factors of pre-diabetic and vascular disease subjects, proper dairy, fish and shellfish intake will be important.

Operation Method of Power Supply System for Eco-friendly Movable-weir Based on Natural Energy Sources (자연에너지를 이용한 친환경 가동보용 전원공급시스템의 운용방안)

  • Kwon, Pil-June;Lee, Hu-Dong;Tae, Dong-Hyun;Park, Ji-Hyun;Ferreira, Marito;Rho, Dae-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.2
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    • pp.601-610
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    • 2020
  • Recently, damage caused by drought is becoming worse and worse due to the global climate change. To overcome these problems, movable-weir to control the water level has been installed instead of a fixed-weir made from concrete. On the other hand, it is difficult to operate an existing moveable-weir because of the high cost of facility management and manpower consumption. In addition, because most moveable-weirs are installed in power systems, the operating cost and the cost of connection for power systems increase when they are located in remote areas. Therefore, this paper proposes an optimal design algorithm and the evaluation algorithm of the SOC (state of charge) of a lithium-ion battery to replace an existing power supply with eco-friendly movable-power with a power supply system using PV modules and lithium-ion batteries. In addition, this study modeled a 50kW power supply system of a movable-weir using PSCAD/EMTDC S/W. The simulation results confirmed that the proposed algorithm has stable operation characteristics in an independent operation mode and interconnection operation mode and that there is the possibility of commercialization with a benefits evaluation of the eco-friendly power supply system of a movable-weir.

Position-Dependent Cathode Degradation of Large Scale Membrane Electrode Assembly for Direct Methanol Fuel Cell (직접 메탄올 연료전지용 대면적 막-전극 접합체 공기극의 위치별 열화 현상)

  • Kim, Soo-Kil;Lee, Eun-Sook;Kim, Yi-Young;Kim, Jang-Mi;Joh, Han-Ik;Ha, Heung-Yong
    • Journal of the Korean Electrochemical Society
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    • v.12 no.2
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    • pp.148-154
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    • 2009
  • With respect to the durability of large scale ($150cm^2$) membrane electrode assembly (MEA) of direct methanol fuel cell (DMFC), degradation phenomena at cathode is monitored and analyzed according to the position on the cathode surface. After constant current mode operation of large scale MEA for 500 hr, the MEA is divided into three parts along the cathode channel; (close to) inlet, middle, and (close to) outlet. The performance of each MEA is tested and it is revealed that the MEA from the cathode outlet of large MEA shows the worst performance. This is due to the catalyst degradation and GDL delamination caused by flooding at cathode outlet of large MEA during the 500 hr operation. Particularly on the catalyst degradation, the loss of electrochemically active surface area (ECSA) of catalyst gets worse along the cathode channel from inlet to outlet, of which the reason is believed to be loss of catalysts by dissolution and migration rather than their agglomeration. The extent of loss in the performance and catalyst degradation has strong relation to the cathode flooding and it is required to develop proper water management techniques and separator channel design to control the flooding.

A Study on Student Players' Mental Strength in Taekwondo Competition from a Philosophical Perspective (철학적 관점에서의 태권도 겨루기 학생 선수 정신력에 관한 연구)

  • Ki-Sam Kim
    • Journal of Industrial Convergence
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    • v.22 no.1
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    • pp.105-115
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    • 2024
  • This study aimed to analyze the impact of mental strength on the competitive performance of student Taekwondo sparring athletes. A total of 343 middle school, high school, and university students registered as Taekwondo sparring athletes with the Korea Taekwondo Association were conveniently sampled. The Mental Toughness Test developed by Loehr was utilized after expert consultations. Data analysis involved t-tests and one-way ANOVA to assess the levels of mental strength sub-factors based on general characteristics, followed by post hoc tests using the Schéffe method for intergroup comparisons. Correlation analysis and multiple regression were conducted to examine the relationship between sub-factors of mental strength and competitive ability. The results indicated significant differences in mental strength sub-factors-confidence, level of awakening regulation, visualization and mental imagery regulation, motivation level, positive energy, and attitude control-based on gender and age among Taekwondo sparring student athletes. In terms of perceived competitive ability, significant differences were found based on age and sports experience. Consequently, beyond psychological training, the study revealed that age and diverse experiences positively influence specific aspects of mental strength among Taekwondo sparring student athletes. Therefore, coaching and training for these athletes, particularly during middle and high school years, should incorporate psychological aspects alongside diverse competition experiences and training to help overcome performance evaluation anxieties during matches.

90-day Repeated-dose Oral Toxicity Study of 20 kGy Irradiated Cold Water Extract Powder of Mistletoe (20 kGy 감마선으로 조사된 겨우살이 냉수 추출물의 90일 반복투여 독성평가)

  • Kim, Jin-Kyung;Jeon, Young-Eun;Yin, Xing Fu;Lee, Ju-Woon;Kang, Il-Jun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.5
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    • pp.704-711
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    • 2011
  • Traditionally, mistletoes have been used as immunostimulant for the management of certain diseases such as cancer with high profile immune depleting potentials. In order to examine the safety of the 20 kGy irradiated cold water extract powder of mistletoes, we performed a 90-day repeated-dose toxicity study with ICR mice. The mice were treated with daily doses of the 20 kGy irradiated cold water extract powder of mistletoes by gavage at 0, 20, 100, and 500 mg/kg/day for 90 consecutive days. We recorded clinical signs of toxicity, body weight, organ weights, histological changes in target organs, hematology, and clinical blood chemistry analysis data for all mice. There were no significant changes in body and organ weights during the experimental period. The hematological analysis and clinical blood chemistry data revealed no toxic effects from the 20 kGy irradiated cold water extract powder of mistletoes. Pathologically, neither gross abnormalities nor histopathological changes were observed between the control and treated mice of both sexes. Collectively, these data suggest that the 20 kGy irradiated cold water extract powder of mistletoes have a high margin of safety.

A Study on the effect of Knowledge workers's Job Characteristics on Organizational Commitment -Shared Leadership as a Moderating variable (지식근로자의 직무특성이 조직 몰입도에 미치는 영향 -공유리더십을 조절 변수로)

  • Jee, Cheoulgyu;Chang, Youngchul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.12
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    • pp.5786-5799
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    • 2012
  • In this era of the knowledge-based economy, the most important issue that we faced is the management of the knowledge workers who is the main source of enterprise. There has been a big issue on the organizational commitment recently which is the idea of how much employees have a positive affection to the enterprise they work for and also how much time, knowledge and energy employees are willing to invest for their company success. Improving this concept would provide a meaningful implication in managing the knowledge workers. This research which is based on previous studies, it aims to control the effect on the organizational commitment by Shared Leadership which puts the job characteristics of knowledge workers into a dominant factor. As a result of the study, among the several job characteristics, autonomy and a feedback had a positive effect on the organizational commitment. Shared Leadership as a moderating variable, has shown an affirmative effect on autonomy, a feedback, and problem solving as an independent variable and on the organizational commitment as a dependent variable. However, related to the job complexity, it did not show a notable influence. Also, the Shared Leadership has shown a favorable impact on the feedback and problem solving, but barely effected on autonomy or job complexity.

A Study on Automatic Precision Landing for Small UAV's Industrial Application (소형 UAV의 산업 응용을 위한 자동 정밀 착륙에 관한 연구)

  • Kim, Jong-Woo;Ha, Seok-Wun;Moon, Yong-Ho
    • Journal of Convergence for Information Technology
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    • v.7 no.3
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    • pp.27-36
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    • 2017
  • In almost industries, such as the logistics industry, marine fisheries, agriculture, industry, and services, small unmanned aerial vehicles are used for aerial photographing or closing flight in areas where human access is difficult or CCTV is not installed. Also, based on the information of small unmanned aerial photographing, application research is actively carried out to efficiently perform surveillance, control, or management. In order to carry out tasks in a mission-based manner in which the set tasks are assigned and the tasks are automatically performed, the small unmanned aerial vehicles must not only fly steadily but also be able to charge the energy periodically, In addition, the unmanned aircraft need to land automatically and precisely at certain points after the end of the mission. In order to accomplish this, an automatic precision landing method that leads landing by continuously detecting and recognizing a marker located at a landing point from a video shot of a small UAV is required. In this paper, it is shown that accurate and stable automatic landing is possible even if simple template matching technique is applied without using various recognition methods that require high specification in using low cost general purpose small unmanned aerial vehicle. Through simulation and actual experiments, the results show that the proposed method will be made good use of industrial fields.

Threshold Condition for Exclusion of Riprap into Bypass Pipe (저층수 배출관에 유입된 사석의 배제 한계조건)

  • Jeong, Seokil;Lee, Seung Oh
    • Journal of Korean Society of Disaster and Security
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    • v.12 no.1
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    • pp.57-66
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    • 2019
  • One of the most serious problems with concrete small dams or barriers installed in small/median rivers is the deposit of sediments, especially, in Korea. An effective way to discharge such sediments to downstream is to construct a bypass pipe under the river bed. However, efficiency may become lowered if ripraps are entered into the bypass pipe. Therefore, in this study, we derived the threshold condition for the exclusion of ripraps from the bypass pipe using 3D numerical analysis. Upstream flow of the small dam was assumed to be stationary, and the energy concept was applied to the control volume containing the bypass pipe and its periphery. As a result, when the ratio of the water level difference between upstream and downstream to the diameter of the riprap was approximately equal to 1.2, the threshold condition for exclusion of the stones or riprap from the bypass pipe was affirmatively determined. If the characteristics of the adsorptive sediment adversely affecting the river environment in the future would be taken into account, results from this study are expected to put to practical use in the management of concrete small dam with bypass pipe system.