• ETRI Journal
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• 제39권1호
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• pp.30-40
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• 2017

In this study, we investigate topology control as a means of obtaining the best possible compromise between the conflicting requirements of reducing energy consumption and improving network connectivity. A topology design algorithm capable of producing network topologies that minimize energy consumption under a minimum-connectivity constraint is presented. To this end, we define a new topology metric, called connectivity efficiency, which is a function of both algebraic connectivity and the transmit power level. Based on this metric, links that require a high transmit power but only contribute to a small fraction of the network connectivity are chosen to be removed. A connectivity-efficiency-based topology control (CETC) algorithm then assigns a transmit power level to each node. The network topology derived by the proposed CETC heuristic algorithm is shown to attain a better tradeoff between energy consumption and network connectivity than existing algorithms. Simulation results demonstrate the efficiency of the CECT algorithm.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제6권9호
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• pp.2302-2322
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• 2012

Wireless Body Area Networks (WBANs) are introduced as an enabling technology in tele-health for patient monitoring. Designing an efficient Medium Access Control (MAC) protocol is the main challenge in WBANs because of their various applications and strict requirements such as low level of energy consumption, low transmission delay, the wide range of data rates and prioritizing emergency data. In this paper, we propose a new MAC protocol to provide different requirements of WBANs targeted for medical applications. The proposed MAC provides an efficient emergency response mechanism by considering the correlation between medical signals. It also reduces the power consumption of nodes by minimizing contention access, reducing the probability of the collision and using an efficient synchronization algorithm. In addition, the proposed MAC protocol increases the data rate of the nodes by allocating the resources according to the condition of the network. Analytical and simulation results show that the proposed MAC protocol outperforms IEEE 802.15.4 MAC protocol in terms of power consumption level as well as the average response delay. Also, the comparison results of the proposed MAC with IEEE 802.15.6 MAC protocol show a tradeoff between average response delay and medical data rate.

• 스마트미디어저널
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• 제8권4호
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• pp.72-79
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• 2019

The automated demand response (DR) program encourages consumers to participate in grid operation by reducing power consumption or deferring electricity usage at peak time automatically. However, successful deployment of the automated DR program sphere needs careful assessment of appliances load profile (ALP). To this end, the recent method estimates frequency, consistency, and peak time consumption parameters of the daily ALP to compute their potential score to be involved in the DR event. Nonetheless, as the daily ALP is subject to varying with respect to the DR time ALP, the existing method could lead to an inappropriate estimation; in such a case, inappropriate appliances would be selected at the automated DR operation that effected a consumer comfort level. To address this challenge, we propose a more proper method, in which all the three parameters are calculated using ALP that overlaps with DR time, not the total daily profile. Furthermore, evaluation of our method using two public residential electricity consumption data sets, i.e., REDD and REFIT, shows that our energy management systems (EMS) could properly match a DR target. A more optimal selection of appliances for the DR event achieves a power consumption decreasing target with minimum comfort level reduction. We believe that our approach could prevent the loss of both utility and consumers. It helps the successful automated DR deployment by maintaining the consumers' willingness to participate in the program.

• 환경영향평가
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• 제6권2호
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• pp.103-112
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• 1997

The object of this study is the introduction and the application of Ecological Footprint(EF) for sustainability of regional people activities. It is a tool for the evaluation of specific projects through various lifestyles or consumption to area of broad policy and budgets. But in Korea there is no assessment for consumption level of human activities by EF. Therefore this study try to analyse ecologically productive land for human activities of Cheju-island in order to assess the sustainability in Cheju and compares with another industrized countries. We analyze the human activities level of Cheju-island then the EF is about 0.9(ha/cap). This value is not more than another countries like Canada and United States. EF assists in choosing technologies, policies and Life Cycle Assessment(LCA) which can perform a certain task with the smallest ecological footprint. It will help society to avoid collapse and move towards sustainability and ecological efficiency.

• 한국농촌생활과학회지
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• 제8권1호
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• pp.1-5
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• 1997

In this study we tried to examine the efficiency of the agricultural convenient tool (put-on-style-stool) by observing subjects'physiological responses. For this we measured subjects' heart rate, oxygen consumption, blood lactate level, mean skin temperature and rectal temperature. The results of this study are as follows; Heart rate was 75$\pm$2 beats/min with the put-on-style-stool and 78$\pm$2 beats/min without it (P＜0.01). Oxygen consumption was 3.88$\pm$1.90 $m\ell$/kg/min with the Put-on-style-stool and 5. 06$\pm$0.40 $m\ell$/kg/min without it (P＜0.05). Blood lactate level was 2.39$\pm$0.64 mmol with the put-on-style-stool and 3.38$\pm$0.45 mmol without it (P＜0.05). Mean skin temperature was lower but rectal temperature was higher with than without the put- on - style - stool (P＜0.05 and P＜0.01 respectively) So, using the put-on-style-stool was evaluated positively in farmer's work.

• The Journal of Asian Finance, Economics and Business
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• 제7권1호
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• pp.313-320
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• 2020

This study aims to analyze the household economic behavior of salt farmers participants in Salt Business Empowerment Program (Pugar) including of salt production, work flow, household revenue, the behavior of consumption of food and non-food items and the welfare level. This research followed a survey method by engaging 32 household farmers as participants. The findings revealed that the empowerment program was carried out through the technical assistance of salting production and the assistance of equipment and technology from Thread of Screw Filter and geoisolators to improve the quality of salt. The problems come when the marketing of salt is still limited to the collectors of salt which led to the price of salt level, manufacturers have not remained stable. Household revenue sources for some salt farmers also come from non-salt pond business activities. Farmer household revenue can be used to meet staple food consumption and non-food staple consumption. Based on the indicators of family welfare, households participating in the empowerment program were group into the category of prosperous families. In order to stabilize the price of salt at the producer level, government intervention in the people's salt trading system is needed.

• 가정과삶의질연구
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• 제24권2호
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• pp.93-106
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• 2006

This study investigated the determinants of Tap Water consumption patterns. Socio-demographic variables(gender, family income, education level, residual area) and consumer attitude knowledge(confidence, knowledge, problem experience, risk perception and aesthetic satisfaction)were included in the analysis. Three hundred fifty-nine teachers were participated in this study. ANOVA(Scheffe test), t-test, regression and logistic regression were conducted. The results of this study are as follows: 1. Tap water was consumed by only 1.7%, boiled water prior to drinking by 37.9%, water filtered by 39.8% and bottled water by 19.0%. 2. Consumer attitude knowledge was affected by socio-demographic variables. That is, aesthetic satisfaction was affected by age, risk perception by gender and educational level, confidence by educational level, knowledge by gender and age, and problem experience by age. 3. Logistic regression analysis indicated that age, confidence and aesthetic satisfaction were the determinants of bottled water or filtered water choice. However, risk perception was not a significant determinant. This suggests alternatives to tap water is related to non-risk, or non-safety factors.

• 성인간호학회지
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• 제17권1호
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• pp.68-76
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• 2005

Purpose: The purpose of the study was to investigate the level of cigarette smoking and alcohol consumption in men with Diabetes Mellitus and to examine the relationships among those variables. Method: The subject consisted of 152 adult men with diabetes mellitus. Q-F methods and FTQ was used to measure the level of alcohol consumption and nicotine dependency. The amount of smoking was measured by the number of cigarette packs used per week. Results: Prevalence of drinking was 63.6% and in the current drinkers, 34.4% were heavy drinkers. The prevalence of cigarette smoking was 36.2% with a mean of 6.03 packs per week. Twenty percent of the smokers were dependent on nicotine. Subjects who had complications or other diseases drank alcohol more than who had not. There was a positive relationship between the level of smoking and nicotine dependency. Conclusion: Alcohol drinking and cigarette smoking is a serious health problem in men with diabetes. It is necessary to have an educational approach for controlling drinking and smoking in diabetes patients.

• JSTS:Journal of Semiconductor Technology and Science
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• 제16권3호
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• pp.300-311
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• 2016

The analog-to-digital-converter-based (ADC-based) backplane receivers that consist of a front-end ADC followed by a digital equalizer are gaining more popularity in recent years, as they support more sophisticated equalization required for high data rates, scale better with fabrication technology, and are more immune to PVT variations. Unfortunately, designing an ADC-based receiver that meets tight power and performance budgets of high-speed backplane link systems is non-trivial as both front-end ADC and digital equalizer can be power consuming and complex when running at high speed. This paper reviews the state of art designs for the front-end ADC and digital equalizers to suggest implementation choices that can achieve high speed while maintaining low power consumption and complexity. Design-space exploration using system-level models of the ADC-based receiver allows through analysis on the impact of design parameters, providing useful information in optimizing the power and performance of the receiver at the early stage of design. The system-level simulation results with newer device parameters reveal that, although the power consumption of the ADC-based receiver may not comparable to the receivers with analog equalizers yet, they will become more attractive as the fabrication technology continues to scale as power consumption of digital equalizer scales well with process.

• 대한가정학회지
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• 제39권6호
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• pp.1-14
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• 2001

The purpose of this research is to observe the differences in consumers behavior on clothes care based on their different lifestyles and different demographic characteristics. The research surveyed 267 women of 20 years old or older living in Taegu City. SPSS package was used for data analysis and frequency, percentage, average, standard deviation, factor analysis, cluster analysis, ANOVA(analysis of valiance). and Duncan test were used The results are as follows: 1. Lifestyle factors for the research object were found as 'Consumption-oriented','family-oriented', 'Economic-oriented','Leisure-oriented','conservatism-oriented'. The categories for analysis according to these factors are classified into 5 categories, category 1 is Leisure/Family-oriented group, category 2 Consumption/Leisure avoidance-oriented group, category 3 Economy/Family Apathy-oriented group, category 4 Conservatism-oriented group, and category 5 Consumption/Innovation group. Five factors for behavior on clothes care are found, including washing method, interest in detergent, environmental behavior, washing effectiveness, and management after washing 2. Behavior on clothes care based on lifestyle groups showed a meaningful difference according to the following: Interest in detergent(p<.05 level), environmental behavior(p<.01 level), and washing effectiveness(p< .01 level) 3. In demographic variations (such as age, monthly income, monthly expenditure on clothes), there is a meaningful difference in behavior on clothes care, such as interest in detergent or management after washing, according to different age groups. However, no meaningful difference is found in behavior on clothes care according to other demographic characteristics.