• The Transactions of the Korean Institute of Electrical Engineers P
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• v.67 no.2
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• pp.112-118
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• 2018

In recent years, decentralized power have been increasing due to environmental problems, liberalization of electricity markets and technological developments. These changes have led to the evolution of power generation, transmission, and distribution into discrete sectors and the division of integrated power systems. Therefore, studies are underway to efficiently supply power and reduce losses to each sector's demand. This is a major concern for system planners and operators, as it accounts for a relatively high proportion of total power, with a transmission and distribution loss of 4-6%. Therefore, this paper analyzes the status of loss management based on the current transmission and distribution loss rate of each country and transmission loss management cases of each national power company, and proposes a loss rate prediction algorithm according to the long-term transmission system plan. The proposed algorithm predicts the demand-based long-term evolution and the loss rate of the grid to which the transmission plan is applied.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.1
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• pp.63-78
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• 2016

To meet nuclear regulatory requirements, more than 95% individual radionuclides in the low- and intermediate-level radioactive waste inventory have to be identified. In this study, the radionuclide inventory has been estimated by taking the long-term radioactive waste generation, the development plan of disposal facility, and the new radioactive waste classification into account. The state of radioactive waste cumulated from 2014 was analyzed for various radioactive sources and future prospects for predicting the long-term radioactive waste generation. The predicted radionuclide inventory results are expected to contribute to secure the development of waste disposal facility and to deploy the safety case for its long-term safety assessment.

• Journal of muscle and joint health
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• v.10 no.1
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• pp.32-43
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• 2003

The purpose of this study was to identify the long-term effects of the self-help program for arthritis patients. The subjects were 126 patients who have participated in the 6-week self-help program from 1997 to 2000, agreed to participate in this study by telephone interview and responded the mailed questionnaires. The measurement tools of this study were all self-reported questionnaires such as Numerical Pain Rating Scale, the number of pain sites, Korean Health Assessment Questionnaire, Numerical Fatigue Rating Scale, CES-D depression scale, Self-efficacy scale, Social support scale. The repeated measure ANOVA revealed the significant differences among the pre post follow-up pain and fatigue. Whileas there were no significant differences the pre post follow-up pain site and physical functioning. And there were also no significant differences the pain, pain site, fatigue and physical functioning among three groups according to the duration of follow-up. These results suggested that the follow-up program after the self-help program was completed would be helpful for the physical wellbeing of arthritis patients.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.8
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• pp.738-743
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• 2012

This paper describes analysis of long-term experiments on a monitoring system to assess the daily activities of the elderly who live alone. The developed system is composed of an in-house sensing system and a server system. The in-house sensing system installed in their own houses is a typical wireless sensor network system including three kinds of wireless sensors. The server system has a database server and an assessment server. We have installed the system into an elderly house, collected data during over two years continuously, then analyze the data. From the analysis, we could measure the energy consumption profile of three kinds of sensor nodes. The experiment shows all kinds of nodes can operate over one year with two AA-size alkaline batteries. Using a measure of reliability of the monitoring system called 'deadzone', the system has showed the failure operation for 842 hours (4.66 %) during over 18,000 hours total operation period.

• Journal of the Society of Naval Architects of Korea
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• v.56 no.2
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• pp.161-167
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• 2019

In general, fatigue analysis is performed by using deterministic model to estimate the optimal parameters. However, the deterministic model is difficult to clearly describe the physical phenomena of fatigue failure that contains many uncertainty factors. With regard to this, efforts have been made in this research to compare with the deterministic model and the stochastic models. Firstly, One deterministic S-N curve was derived from ordinary least squares technique and two P-S-N curves were estimated through Bayesian-linear regression model and Markov-Chain Monte Carlo simulation. Secondly, the distribution of Long-term fatigue damage and fatigue life were predicted by using the parameters obtained from the three methodologies and the long-term stress distribution.

• Journal of Korean Public Health Nursing
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• v.23 no.2
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• pp.232-250
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• 2009

Purpose: This study was designed to define the roles, tasks, and activities of home visiting nurses aimed at enhancing the quality of nursing care under the long-term care insurance regulation for the elderly introduced on July 1, 2008 in Korea. Methods: A review of domestic and foreign literature was used to formulate the proposed roles, tasks, and activities of visiting nurses, which were subsequently modified and complemented by the agreement of home visiting nurse experts and acceptance of 127 nurses. Data was collected from 04 June - 17 September 2008 and analyzed concerning frequency and percentile using SPSS ver. 15.0. Results: The established functions of home visiting nurses were direct nursing service provider, case manager, patient educator, decision maker, care coordinator, and research worker. These functions involved 27 different tasks and 167 activities. Conclusion: The roles, tasks, and activities of visiting nurses, established based upon the guidelines of the Long-term Care Insurance Act for the elderly, were verified for their applicability by nurses involved in home care delivery. These parameters will provide a useful tool in developing an assessment to enhance the quality of home-based care for the elderly in Korea.

• Journal of the Korean Data and Information Science Society
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• v.26 no.3
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• pp.715-727
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• 2015

This study was conducted to explore the impact of nursing staffing on inpatient nursing outcomes in long term care hospitals. A secondary analysis was done of national data from the Health Insurance Review and Assessment Services including evaluation of long term care hospitals. Patients per RN was a significant indicator of foley catheter ratio in high risk group and low risk group. Patients per RN&NA was a significant indicator of decline in ADL for patients with dementia, non dementia, urinary incontinence and new pressure ulcer development in the high risk group. The average nursing outcome of inpatient in high grade was higher than that low grade in long care hospital. This higher level of nursing staffing and the higher the grade shown a positive effect on the nursing outcomes of the inpatient. We therefore recommend modifying the above nurse staffing policy so as to make it more effective in improving nursing outcomes.

• Advanced Composite Materials
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• v.17 no.3
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• pp.247-258
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• 2008

This paper is concerned with the long-term performance of geo-textile (GT) composites in terms of creep deformation and frictional properties. Composites of PVA GT and HDPE GM were made to investigate the advanced properties of long-term performance related to waste landfill applications. The same experiments were also performed for typical polypropylene and polyester GT and compared to PVA GT/HDPE GM composites. We also develop high performance GT composites with GM by using PVA GT, which is capable of improving the frictional properties and thus enhances long-term performance of GT composites. Experimental study reveals that the friction coefficient of GT composites is relatively large compared with those of polyester and polypropylene non-woven GT as long as the friction media has similar size to the particles of domestic standard earth. In addition, the geo-composites bonded with geo-grid by a chemical process were investigated experimentally in terms of strain evaluation and creep response values. Geo-grid plays an important role as a reinforcing material. Three kinds of geo-grid were prepared as strong yarn polyester and they were woven type, non-woven type, and wrap knitted type. The sample geo-grids were then coated with PVC. The rib tensile strength tests were conducted to evaluate geo-grid products in terms of tensile strength with regard to single rib. The test was performed according to GRI-GGI. It was concluded again from the experiments that the tensile and creep strains of the geo-grid showed such stable values that the geo-grid prepared in this study could protect geo-textile partially in practical structures.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.4
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• pp.391-404
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• 2021

This study developed a long-term prediction model for the potential yield of garlic based on a genetic algorithm (GA) by utilizing global climate reanalysis data. The GA is used for digging the inherent signals from global climate reanalysis data which are both directly and indirectly connected with the garlic yield potential. Our results indicate that both deterministic and probabilistic forecasts reasonably capture the inter-annual variability of crop yields with temporal correlation coefficients significant at 99% confidence level and superior categorical forecast skill with a hit rate of 93.3% for 2 × 2 and 73.3% for 3 × 3 contingency tables. Furthermore, the GA method, which considers linear and non-linear relationships between predictors and predictands, shows superiority of forecast skill in terms of both stability and skill scores compared with linear method. Since our result can predict the potential yield before the start of farming, it is expected to help establish a long-term plan to stabilize the demand and price of agricultural products and prepare countermeasures for possible problems in advance.

• Journal of Environmental Impact Assessment
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• v.19 no.3
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• pp.335-345
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• 2010

This paper assessed environmental impacts of marine sand mining on coastal areas and Exclusive Economic Zones (EEZs) of Korea, and diagnosed problems of the related assessment statements for suggesting key assessment items (scoping) and system improvement. To mitigate conflicts and environmental impacts caused by large-scale, concentrated sand mining, we suggest it is critical to promote sustainable and eco-friendly utilization of marine resources while listening opinions from various stakeholders and analyzing alternative plans. Especially, it should be mandatory as a scoping item to provide verifiable data on the amount of sand, potential and accumulative impacts by mining, and key assessment items (e.g. erosion and sedimentation by submarine topography, benthic change, spreading of suspended solids, water pollution, grain-size change, and impact on fisheries resources). We also suggest that postassessment and monitoring should be improved to enable tracking of environmental impacts caused by sand mining through seasonal monitoring together with intermittent short-term surveys. In addition, effective measures to mitigate the impacts is also essential. As repeated sand mining at large-scale can damage marine ecosystems by long-term accumulated impacts, we suggest that assessment systems and regulatory policies should be developed and established, especially for ensuring reliability of assessment and review on selected major sandmining projects.