• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.6
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• pp.1479-1495
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• 2012

Spectrum scarcity seems to be the most challenging issue to be solved in new wireless telecommunication services. It is shown that spectrum unavailability is mainly due to spectrum inefficient utilization and inappropriate physical layer execution rather than spectrum shortage. Daily increasing demand for new wireless services with higher data rate and QoS level makes the upgrade of the physical layer modulation techniques inevitable. Orthogonal Frequency Division Multiple Access (OFDMA) which utilizes multicarrier modulation to provide higher data rates with the capability of flexible resource allocation, although has widely been used in current wireless systems and standards, seems not to be the best candidate for cognitive radio systems. Filter Bank based Multi-Carrier (FBMC) is an evolutionary scheme with some advantages over the widely-used OFDM multicarrier technique. In this paper, we focus on the total throughput improvement of a cognitive radio network using FBMC modulation. Along with this modulation scheme, we propose a novel uplink radio resource allocation algorithm in which fairness issue is also considered. Moreover, the average throughput of the proposed FBMC based cognitive radio is compared to a conventional OFDM system in order to illustrate the efficiency of using FBMC in future cognitive radio systems. Simulation results show that in comparison with the state of the art two algorithms (namely, Shaat and Wang) our proposed algorithm achieves higher throughputs and a better fairness for cognitive radio applications.

• Journal of the Korean Society for Library and Information Science
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• v.45 no.2
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• pp.345-366
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• 2011

The law affects our daily lives, and hence, constitutes a crucial information resource. However, electronic access to legal information using keyword-based retrieval systems appears to provide users with limited satisfaction. There are many factors behind this inadequacy. First, the discrepancies between formal legal terms and their counterparts in common language are quite large. Second, the situation is further confounded by frequent abbreviations in legal terms. Third, even though there is a constant deluge of legal information, users' needs have evolved to demand more Q and A type searches. All of these factors make the existing retrieval systems inefficient and ineffective. This article suggests an ontology-based system as a means to deal with such difficulties. To that end, a legal retrieval system(experimental system), built on the basis of a newly-constructed law ontology, was tested against a keyword-based legal retrieval system(existing one), yielding data on their relative effectiveness in retrieval and user satisfaction.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.747-749
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• 2013

Aging our country is facing now is seeking qualitative and quantitative expansion of social welfare services. In particular, the rapid increase in the aging population is an urgent need to resolve the problems of inducing demand for medical care and various welfare related to the elderly, In addition, IT technology in Korea is improving daily, in particular, fields of ubiquitous have been studied actively. In this paper, U-Health Care System model technology for the elderly were studied. Existing residential and senior living environment dedicated to the Care system for the fusion of design, and content designed around the ubiquitous technology that combines the old Care system was studied. Existing community-based model that combines technology and IT systems and mobile elderly Care services in conjunction with other devices by providing an application, the existing Care and medical needs will be able to solve the problems.

• The Journal of Korean Medicine
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• v.19 no.2
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• pp.468-484
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• 1998

The purpose of this study was to explore the development of oriental health promotion project in korea. The study was performed from June 10, 1998 though June 30, 1998 by using questionnaires and the subjects were 208 in Taegu and Kyung-san city. The analysis methods were frequency, percentage, $x^2-test$ and ANOVA. The SAS/pc Program was used for the statistic analysis. The major findings are as followings; 1. The self-confidence of health was higher among male(2.59) than female(2.94). On the whole, the subjects studied have good health. Activity of daily life was medium. 2. As the subjects grow old, satisfaction level on health counselling with oriental doctors was high. Hospital and clinic covered 60-80% of the health assessment institutes and oriental hospital & clinic covered 10-18% of them. 3. As the subjects grow old was high the level of health promotion practice. On the whole, the level of health promotion practice was low. The physical exercise was highest covering 40% in the types of health promotion. 4. On the whole, the demand of oriental health promotion program was considerably high (male 2.06, female 2.49). The reason why the health promotion programs were necessary was necessary was the effectiveness of health promotion and the difficulty of self-practice. In the effectiveness of health promotion programs, the subjects were higher in oriental medicine than medicine. 5. In the validity level of physical constitution in the oriental medicine. the subject were high(3.48-3.80). But the necessity of the physical constitution change was medium.

• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.5
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• pp.1-9
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• 2014

The DIROM (Daily Irrigation Reservoir Operation Model) was modified to estimate amounts of water release from reservoirs, considering customary irrigation water management practices, such as water supply for puddling and transplanting paddy rice from seeding beds and mid-season drainage. The applicability of the modified model was investigated by simulating amounts of water release from three study reservoirs: Hwamae, Ogi, and Doya Reservoirs. In terms of annual amounts of water release, the relative errors between the observed and simulated values in 2012 and 2013 ranged -26.20 % to 10.28 % and 4.90 % to 30.06 %, respectively; in case of reservoir water levels, the RMSE values ranged 0.45 m to 1.34 m and 0.40 m to 1.27 m, respectively. Also, it was revealed that the model provided better simulation results for monthly water releases than the original model. In addition, the model presented better performance in simulating 10-day amounts of water release from April to June. However, the model had still significant errors in the simulation results from July to September because the reservoirs were practically operated to adapt to water management circumstances. Finally, it is concluded that the modified DIROM can estimate the amounts of water release from reservoirs, reflecting irrigation water management customs in paddy-field districts. To achieve higher prediction accuracy of the model, it is necessary to incorporate practical reservoir operation rules into the model.

• Journal of Digital Convergence
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• v.14 no.12
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• pp.441-449
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• 2016

Today, as a daily routine such as administration/finance is operated under information system and various cyber crime against national, public, and private institutions happen, demand for information security manpower is increasing. Hence, Ministry of Education has formed an Institute of Information Security Education for the Gifted to early discover talent in the field of information security and train professional personnel with specialty and ethics in 4 universities of country in 2014. But the nascent Institute of Information Security Education for the Gifted lack systematic analyses compared to Institute of Mathematics and Science Education for the Gifted that has existed from a long time ago. In this paper, we analyze the state of the Institute of Information Security Education for the Gifted in three parts: operation, selection, education and suggest an improvement to build a practical program for effective operations and education.

• Journal of Environmental Health Sciences
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• v.30 no.3
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• pp.272-282
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• 2004

Stress is a primary health promotion issue in worksite research because psychological distress is closely related not only to workers　 health status but also to their job performance. This study identified the work environment and work condition factors affecting workers　 stress symptoms among the Korean manufacturing factory workers. A total of 7,818 factory workers employed in 1,562 manufacturing companies participated in the Korean nation-wide occupational health survey conducted by the Korean Occupational Safety and Health Agency in 2003. Participants were selected by the stratified proportional sampling process by standardized industry classification, company size, and locations. Trained interviewers visited the target companies and interviewed the factory workers randomly selected in each company. Work environments included physical work environments (temperature, noise, hazardous organic compounds, and so on) and psychological work environments (job demands, job control, and social support at work), and work conditions included daily working hour, rest time, and so on. Men were 71.5% and the mean age was 34.0 years old. The average working period in the present company was 6.9 years. The average stress score was 26.2 under the perfect score, 50, which means the moderate level of stress. Perceived stress had significant correlations with young age, poor physical work environment, high fatigue, bad perceived health status, and high job demands in Pearson's simple correlation analysis. Perceived health status and perceived fatigue explained 21% variance of stress symptoms and the work environment factor explained 4.8% of that; however, work condition did not have the sufficient effect. In particular, psychosocial work environment variables (job demand, job control, and social support at work) had a clear effect on stress symptoms rather than the physical work environments. Poor perceived health status, severe perceived fatigue, poor physical work environment, high job demands, low social support, heavy alcohol consumption and little exercise were significantly related to high stress symptoms in the Korean manufacturing workers.

• Research in Community and Public Health Nursing
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• v.12 no.3
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• pp.582-588
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• 2001

Purpose : This study is to examine the characteristics of the elderly and their family caregivers. to study the main factors affecting Nursing Home utilization, and to help frame a policy about Nursing Home's demand. management and welfare facilities. Method: Data for this present study were collected via questionnaires randomly distributed to family caregivers of the over 60-year-old patients at general hospital and university hospital in Seoul. Kyung-Ki Do and In-Chon from 26 June to 20 July, 2000. Questionnaires were issued to 512 people and 479 were returned. The data was analyzed by frequency, $x^2$-test, t-test, ANOVA. factor analysis. correlation coefficients analysis and Stepwise multiple regression analysis using SPSS 9.0. Result First. Instrumental Activities of Daily Living(IADL), duration of hospitalization, sex, marital status, behavior problems, home ownership, and cognitive disorder about elderly patients affect family caregivers burden. one of need factors. Secondly, marital status. religion. health status, sex, education and age in the family caregiver predisposing factors are main factors on Nursing Home utilization. Third, in need factors, care burden. time burden, family relation burden, physical burden and mental burden have an effect on Nursing Home utilization. Finally, the model the most important factors that affect Nursing Home utilization is composed of six of eleven totally, care burden, religion, time burden, health status, marital status and education. When the family caregivers get care burden and time burden. are highly educated, have no religion, have health problems, and have no spouse, it is possibility for them to utilize Nursing Homes. Conclusion: The government should decrease a family caregivers burden and seek to find how to support Nursing Homes. Furthermore. Social support program for the family caregivers should be required. Thus, the family caregivers need consultation and need to meet to talk about their patients. how to care them, get information, which are the crucial field in advancing the research in nursing science.

• Journal of the Korean Institute of Gas
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• v.23 no.5
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• pp.52-58
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• 2019

In this study, we have developed a forecasting model for city- gas acceptance. City-gas corporations have to report about city-gas sale volume next year to KOGAS. So it is a important thing to them. Factors influenced city-gas have differences corresponding to usage classification, however, in city-gas acceptence, it is hard to classificate. So we have considered tha outside temperature as factor that influence regardless of usage classification and the model development was carried out. ARIMA, one of the traditional time series analysis, and LSTM, a deep running technique, were used to construct forecasting models, and various Ensemble techniques were used to minimize the disadvantages of these two methods.Experiments and validation were conducted using data from JB Corp. from 2008 to 2018 for 11 years.The average of the error rate of the daily forecast was 0.48% for Ensemble LSTM, the average of the error rate of the monthly forecast was 2.46% for Ensemble LSTM, And the absolute value of the error rate is 5.24% for Ensemble LSTM.

• Industrial Engineering and Management Systems
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• v.8 no.2
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• pp.80-92
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• 2009

This paper addresses the inventory rationing issue embedded in the regional supply chain inventory replenishment problem (RSIRP). The concerned supply chain, which was fed by the national supply chain, consisted of a single warehouse distributing a single product to multiple stores (M-stores) with independent and normally distributed customer demand. It was assumed that the supply chain operated under the order-up-to level inventory replenishment system and had only one truck at the regional warehouse. The truck could make one replenishment trip to one store per period (a round trip per period). Based on current inventories and the vehicle constraint, the warehouse must make two decisions in each period: which store in the region to replenish and what was the replenishment quantity? The objective was to position inventories so as to minimize lost sales in the region. The warehouse inventory was replenished in every fixed-interval from a source outside the region, but the store inventory could be replenished daily. The truck destination (store) in each period was selected based on its maximum expected shortage. The replenishment quantity was then determined based on the predetermined order-up-to level system. In case of insufficient warehouse inventories to fulfill all projected store demands, an inventory rationing rule must be applied. In this paper, a new inventory rationing rule named Expected Cost Minimization (ECM) was proposed based on the practical purpose. The numerical results based on real data from a selective industry show that its performance was better and more robust than the current practice and other sharing rules in the existing literature.