• Journal of The Korean Society of Agricultural Engineers
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• v.66 no.1
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• pp.1-13
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• 2024

This study assessed the efficacy of improving the accuracy of reservoir water level prediction models by employing automated machine learning models and efficient cross-validation methods for time-series data. Considering the inherent complexity and non-linearity of time-series data related to reservoir water levels, we proposed an optimized approach for model selection and training. The performance of twelve models was evaluated for the Obong Reservoir in Gangneung, Gangwon Province, using the TPOT (Tree-based Pipeline Optimization Tool) and four cross-validation methods, which led to the determination of the optimal pipeline model. The pipeline model consisting of Extra Tree, Stacking Ridge Regression, and Simple Ridge Regression showed outstanding predictive performance for both training and test data, with an R² (Coefficient of determination) and NSE (Nash-Sutcliffe Efficiency) exceeding 0.93. On the other hand, for predictions of water levels 12 hours later, the pipeline model selected through time-series split cross-validation accurately captured the change pattern of time-series water level data during the test period, with an NSE exceeding 0.99. The methodology proposed in this study is expected to greatly contribute to the efficient generation of reservoir water level predictions in regions with high rainfall variability.

• The Journal of Korean Physical Therapy
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• v.24 no.3
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• pp.191-197
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• 2012

Purpose: This study investigated the relationship between degree of stress and quality of life in mothers of children with cerebral palsy. Methods: This study's subjects were 77 mothers of children under 10 years of age with cerebral palsy. The instrument is a self-administered, structured, written questionnaire. The tool that measured the degree of stress was created by modifying the questionnaire by Park (2004). Quality of life for all mothers with cerebral palsy was evaluated by the ShortForm-36 Health Questionnaire. To verify the effects on degree of stress and quality of life arising from general characteristics, t-tests and ANOVAs were conducted. The correlation between degree of stress and quality of life was analyzed via Pearson's correlation analysis. Results: The mothers' degree of stress was rated as 2.69 out of 5; their quality of life was rated as 53.07 out of 100. There was a significant negative correlation between quality of life and the age of cerebral palsy and positive correlations between quality of life and mother's age, background, and family income. Degree of stress among mothers has a positive correlation with quality of life. Conclusion: This study provides basic data about the relationship between degree of stress and quality of life in mothers of children with cerebral palsy.

• Mycobiology
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• v.48 no.2
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• pp.139-147
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• 2020

Root-feeding Scarabaeidae, particularly white grubs are considered among the most harmful coleopteran insect pests in turfgrass. In this work, sixteen entomopathogenic fungal species were assayed against flower chafer beetle, Protaetia brevitarsis (Coleoptera: Scarabaeidae) and Metarhizium anisopliae JEF-314 showed high virulence. The control ability of the isolate JEF-314 has been in detail tested for a model insect flower chafer beetle. Further analyses showed insect stage-dependent virulence where the fungal virulence was the highest against smaller instar larvae. Additionally, we confirmed that millet-based solid cultured granule was effective against the soil-dwelling larval stage. The isolate also showed a similar ability for a representative pest (Popillia spp.) in laboratory conditions. Our results clearly suggest a high potential of M. anisopliae JEF-314 to control the flower chafer beetle, possibly resulting in controlling of root-feeding white grubs in turfgrass. Based on the insect life cycle and susceptibility to the fungus, late spring and summer time would be the optimum time to apply JEF-314 granules for an effective control. Further characterization of the efficacy of the fungus under field conditions against the Scarabaeidae beetles might provide an efficient tool to control this beetle in an environment-friendly way.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.25 no.12
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• pp.895-900
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• 2015

Most of spindles for machine tool are supported by ball bearings, and there are problems in the limits of high speed and high power as well as the cumbersome maintenance due to the short life time. In order to overcome these problems of the conventional spindles, the high speed spindle with magnetic bearings is developed in this study. Magnetic bearings for 60 000 r/min class high-speed spindle are designed, and high speed spindle with magnetic bearings are fabricated. Based on the running test up to 60 000 r/min, it is verified that the spindle is stably supported by the magnetic bearings, and the magnitude of the unbalance response at 60 000 r/min is less than $3{\mu}m$.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.4
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• pp.335-343
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• 2013

If the SW weaknesses, which are the main cause of cyber breaches, are analyzed and removed in the SW development stages, the cyber breaches can be prevented effectively. In case of Domestic, removing SW weaknesses by applying Secure SDLC(SW Development Life Cycle) has become mandatory. In order to analyze and remove the SW weaknesses effectively, reliable SW weakness diagnostic tools are required. Therefore, we propose the functional requirements of diagnostic tool which is suitable for the domestic environment and the evaluation methodology which can assure the reliability of the diagnostic tools. Then, to analyze the effectiveness of the proposed evaluation framework, both demonstration results and process are presented.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.5A
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• pp.441-450
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• 2007

In this paper, it is proposed the link performance analysis results using SNRAT(Satellite Network Resource Allocation & Analysis Tool) and verified the anticipated results by satellite communication network simulator. A communication satellite cannot be corrected or fixed for the error in orbit operation after launching unlike the ground operation equipment and has a restricted operation life. So, it is important to make possible to use satellite communications in the proper time. It is expected the link BER(Bit Error Rate), throughput and AJ(Anti-Jamming) performance using SNRAT tool before launching. And it is verified the performance of the repeaters and ground equipment specification using the satellite network simulator and is extracted the optimum operational scenarios through the tests of various network operational plans.

• Journal of Korean Academy of Nursing
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• v.27 no.3
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• pp.601-613
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• 1997

This project was conducted using a survey method and through interviewing with four persons aged 60 years and over. An interview with an open-ended questionnaire was also used for elderly persons, families, oriental medicine doctor and nurses. topic-related literature review was also done. In total, 382 statements were derived. For content validity, nursing professionals were involved in this study, From that 48 items are developed. The subjects were 340 elderly persons over 60 years old. Data were collected duicing February and March 1997 and analyzed using the SPSS package The result are as follows. 1. Items with low Cronbach Coefficient alpha which means low correlation with total items were removed. 2. Factor analysis was done in order to confirm construct validity and eight factors were obtained from the results. The first factor, 'positive cognition of the aging process', the second factor, 'relationship network' the third factor, 'maintanence of physical functioning, the fourth factor', 'maintanence of peaceful mind' the fifth factor, 'keeping up with daily tasks' the sixth factor, 'continuous adequate body movement' the seventh factor,'involvement of religion in the elderly person's life and the eight factor', 'appropriate resting'. Cronbach Coefficient alpha for the 33 items was .9127 Based on the result, the following is suggested 1. It is anrticipated that the fundamental health of elderly person could be promoted by assessing healthy behaviors of elderly person with this assessment tool. 2. Further studies could be derived from this research. 3. Validity of this assessment tool should be further tested with and a larger sample of elderly person including in-patient elderly persons as well as nursing home residents.

• Korean Journal of Adult Nursing
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• v.17 no.3
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• pp.411-424
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• 2005

Purpose: The purpose of this study was to develop and evaluate e-EBPP(Evidence-based Practice Protocol) system for nursing care for patients with dementia to facilitate the best evidence-based decision in their dementia care settings. Method: The system was developed based on system development life cycle and software prototyping using the following 5 processes: Analysis, Planning, Developing, Program Operation, and Final Evaluation. Result: The system consisted of modules for evidence-based nursing and protocol, guide for developing protocol, tool for saving, revising, and deleting the protocol, interface tool among users, and tool for evaluating users' satisfaction of the system. On the main page, there were 7 menu bars that consisted of Introduction of site, EBN info, Dementia info, Evidence Based Practice Protocol, Protocol Bank, Community, and Site Link. In the operation of the system, HTML, JavaScript, and Flash were utilized and the content consisted of text content, interactive content, animation, and quiz. Conclusion: This system can support nurses' best and cost-effective clinical decision using sharable standardized protocols consisting of the best evidence in dementia care. In addition, it can be utilized as an e-learning program for nurses and nursing students to learn use of evidence based information.

• Journal of Korean Society of Rural Planning
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• v.16 no.4
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• pp.13-22
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• 2010

Rural landscape is an outcome of residents' life activity based on natural environment. Unlike city, rural residents make their own landscape over a period of time interacting with nature through cultivating and building houses and huts based on the background. Therefore, residents' role in rural area is of greater importance than city's and their recognition of landscape is a key factor to evaluate and manage rural landscape. Landscape Evaluation Map which utilizing Feeling Map method is a evaluation tool to [md out residents' recognition of landscape. In this tool, responses evaluate landscape around their living space and mark color dots which mean landscape grade on a map. This research is to examine effectiveness and applicability of the tool, Landscape Evaluation Map, which is recommended to estimate residents' evaluation of landscape. Through analyzing 7 cases of field application, the effectiveness of Landscape Evaluation Map has been verified and also demerits have been drawn. After modifying detailed techniques and developing resident education, Landscape evaluation map could be applied to [md out landscape resources rather than to evaluate whole rural landscape.

• Transactions of Materials Processing
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• v.22 no.4
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• pp.204-215
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• 2013

As a pressure vessel, a small seamless aluminum liner with inner volume of about 6.75L is made from an initial billet material of AA6061-O. To produce the aluminum liner, warm forging including backward extrusion and head nosing was numerically simulated using a billet initially pre-heated to about $480^{\circ}C$. Compression tests on the billet material were performed at various temperatures and strain rates, and the measured mechanical properties were used in the numerical simulations. For the backward extrusion and the head nosing, the tool geometries were designed based on the desired configuration of the aluminum liner. Furthermore, the structural integrity of the tooling was evaluated to ensure adequate tool life. The seamless aluminum liner has an endurance limit of about 1.47MPa ($15Kg_f/cm^2$), estimated based on the required inner pressure. The results confirm that the small seamless aluminum liner of AA6061-O can be successfully made by using the two stage warm forging procedures without any bursting failures.