• Journal of Electrical Engineering and Technology
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• v.10 no.4
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• pp.1422-1431
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• 2015

The reliability of power system components can be affected by a numbers of factors such as the health level of components, external environment and operation environment of power systems. These factors also affect the electrical parameters of power system components for example the thermal capacity of a transmission element. The relationship of component reliability and power system is, therefore, a complex nonlinear function related to the above-mentioned factors. Traditional approaches for reliability assessment of power systems do not take the influence of these factors into account. The assessment results could not, therefore, reflect the short-term trend of the system reliability performance considering the influence of the key factors and provide the system dispatchers with enough information to make decent operational decisions. This paper discusses some of these important operational issues from the perspective of power system reliability. The discussions include operational reliability of power systems, reliability influence models for main performance parameters of components, time-varying reliability models of components, and a reliability assessment algorithm for power system operations considering the time-varying characteristic of various parameters. The significance of these discussions and applications of the proposed techniques are illustrated by case study results using the IEEE-RTS.

• Structural Engineering and Mechanics
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• v.46 no.5
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• pp.629-644
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• 2013

This paper concerns about the raking damages on the ultimate residual hull girder strength of bulk carriers by applying the modified R-D diagram (advanced method). The limited raking damage scenarios, based on the IMO's probability density function of grounding accidents, were carried out by using sampling technique. Recently, innovative method for the evaluation of the structural condition assessment, which covers the residual strength and damage index diagram (R-D diagram), was proposed by Paik et al. (2012). This concept is applied in the present study and modified R-D diagram, which can be considered vessel size effect, is then proposed. Four different types of bulk carrier structures, i.e., Handysize (37K), Supramax (57K), Kamsarmax (82K) and Capesize (181K) by Common Structural Rule (CSR), were applied to draw the general tendency. The ALPS/HULL, intelligent supersize finite element method, was employed for the ultimate longitudinal strength analysis. The obtained empirical formulas will be useful for the condition assessment of bulk carrier structures. It can also cover different sizes of the bulk carriers in terms of ultimate longitudinal strength. Important insights and findings with useful guidelines developed in this study are summarized.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.3
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• pp.592-606
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• 2011

Currently, the development of multimedia communication has progressed so rapidly that the video program service has become a requirement for ordinary customers. The quality of experience (QoE) for the visual signal is of the fundamental importance for numerous image and video processing applications, where the goal of video quality assessment (VQA) is to automatically measure the quality of the visual signal in agreement with the human judgment of the video quality. Considering the codec effect to the video quality, in this paper an efficient non-reference (NR) VQA algorithm is proposed which estimates the video quality (VQ) only by utilizing the distorted video signal at the destination. The VQA feature vectors (FVs) which have high relationships with the subjective quality of the distorted video are investigated, and a hybrid NR VQA (HNRVQA) function is established by considering the multiple FVs. The simulation results, testing on the SDTV programming provided by VCEG Phase I, show that the proposed algorithm can represent the VQ accurately, and it can be used to replace the subjective VQA to measure the quality of the video signal automatically at the destinations.

• Hwankyungkyoyuk
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• v.19 no.1 s.29
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• pp.43-63
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• 2006

The purpose of this study was to evaluate elementary students' environmental mapping following an environmental literacy degree. For this purpose, 34 elementary students of the 5th grade in Daejeon were used as a sample, and their environmental literacy(EL) by 'environmental literacy inventory(ELI)' was assessed. In the end, the correlation between EL and 'Environmental Mapping' was analyzed. The major findings of this study were as follows: 1) 5th grade elementary school students have a high level of conceptual recognition in regard to environmental issues and problems but they have low level of environmental behavioral function; 2) in the correlational analysis of environmental Mapping assessment and EL degree have significant correlation at p<.01 ; 3) environmental issue knowledge and environmental susceptibility have significant correlation in environmental Mapping and p<.01; 4) in the correlation analysis of environmental Mapping assessment and environmental target level, fundamental elements and conceptual recognition have significant correlation at p<.01 and environmental behavior and function on environment have significant correlation at p<.05.

• Journal of the Korean Society of Physical Medicine
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• v.18 no.2
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• pp.93-101
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• 2023

PURPOSE: The Western Ontario and McMaster Universities Arthritis (WOMAC) index has been used to measure the outcome of total knee replacement (TKR), but studies on its reliability and validity are limited. The present study examined the reliability and validity of this index for patients with knee osteoarthritis who underwent TKR. METHODS: Seventy-one inpatients and outpatients who underwent bilateral TKR for knee osteoarthritis were included in this study. The pain assessment scale and WOMAC index were used to evaluate the participants every two weeks to examine the test-retest reliability, internal consistency, and construct validity. RESULTS: The test-retest reliability scores for pain, stiffness, and physical function were .75-.92, .85-.90, and .75-.95, respectively. The corresponding intraclass correlation coefficients were .75-.88, .76-.88, and .71-.95, respectively. The internal consistency score in the first and second examinations was .92. Furthermore, the construct validity scores for pain, stiffness, and physical function were .83, .41, and .58, respectively. CONCLUSION: The application of the WOMAC index in patients who underwent TKR showed high test-retest reliability and internal consistency with the use of the WOMAC index and good validity with the use of the pain assessment scale.

• Journal of Environmental Health Sciences
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• v.46 no.6
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• pp.667-675
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• 2020

Objectives: Exposure to fine dust (PM10) could contribute to the occurrence of cardiovascular disease or respiratory abnormalities. Since garlic is known to possess an anti-oxidative stress effect, the present study was performed to evaluate the effect of garlic intake on fine dust-mediated pulmonary toxicity. Methods: Rats were intratracheally instilled with fine dust at 15 mg/kg body weight (BW)/day for five days following five-day intragastric intubation of garlic at 0.7 or 1.4 g/kgBW/day, or 13.1 mg/kgBW/day S-allyl-cysteine (SAC) as a reference component in garlic. Blood and bronchoalveolar lavage fluid (BALF) were collected. Results: Deposit of fine dust was visually and histopathologically observed in the lungs. Body weight gain during the instillation period was significantly lowered in all the groups instilled with fine dust. Neutrophil numbers in blood were significantly elevated in the fine dust alone group, but this alteration was diminished in the groups administered with garlic. Levels of serum glutathione were lower in the rats instilled with fine dust alone, and this decrease in the glutathione level seems dose-dependently compensated among the groups administered with garlic. Similar findings were observed in the BALF with statistical significance. Typical pulmonary histopathological observation related with inflammation was demonstrated in the lungs of the rats exposed to fine dust alone, whereas such histopathologic findings were not improved in the groups administered with garlic. Conclusion: The present study suggests that garlic intake could alleviate fine dust-mediated pulmonary or systemic toxicities. Further investigation is necessary to delineate the mechanism of garlic-mediated effects on pulmonary function.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.7
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• pp.3245-3271
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• 2016

To obtain well-dehazed images at the receiver while sustaining low bit rates in the transmission pipeline, this paper investigates the effects of image dehazing methods using dehazing contrast-enhancement filters on image compression for surveillance systems. At first, this paper proposes a novel image dehazing method by using a new method of calculating the transmission function—namely, the direct denoising method. Next, we deduce the dehazing effects of the direct denoising method and image dehazing method based on dark channel prior (DCP) on image compression in terms of ringing artifacts and blocking artifacts. It can be concluded that the direct denoising method performs better than the DCP method for decompressed (reconstructed) images. We also improve the direct denoising method to obtain more desirable dehazed images with higher contrast, using the saliency map as the guidance image to modify the transmission function. Finally, we adjust the parameters of dehazing contrast-enhancement filters to obtain a corresponding composite peak signal-to-noise ratio (CPSNR) and blind image quality assessment (BIQA) of the decompressed images. Experimental results show that different filters have different effects on image compression. Moreover, our proposed dehazing method can strike a balance between image dehazing and image compression.

• Korean Journal of Adult Nursing
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• v.16 no.2
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• pp.245-255
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• 2004

Purpose: this study was to evaluate Cognitive Function Test for the Korean population. Digit Forward (DF), Digit Backward (DB) and Trail Making Test-A(TMT-A) and the translated version of the Trail Making Test-B (TMT-B) were used. The study examined the performance of Korean normal adult population whose age ranged from 20 to over 80. It was predicted that performances of the Korean population would be different from that of the United States population due primarily to their differences in language, and education. Method: Normal Korean adults at the Daejeon Metropolitan City and Chungchung Province (N=298) participated in this study. Seven age scores were evaluated; 20~29, 30~39, 40~49, 50~59, 60~69, 70~79, & >80s. The effects of age, gender, and years of education was examined, which yielded significant age and education effects. The scores were further specified accordingly in terms of years of education (0, 1~6, 7~12, 13~16, & >17), and gender. Result: As the age increased cognitive function score decreased. As the years of education increased, cognitive function scores increased. There was no difference in cognitive function scores according to gender. Age and year of education had significant effects on cognitive function and explained 52-58% of variants of each test. Conclusion: The data of the cognitive function tests are expected to be utilized for research purposes such as basic and clinical studies, as well as practical purpose such as cognitive assessment for traumatic brain injury, stroke, and elderly and nursing education for assessment tools.

• Journal of Environmental Impact Assessment
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• v.21 no.1
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• pp.119-132
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• 2012

Biodiversity is a key element of ecosystem of which function provides essential product and service in human life. In the course since development projects often causes damages to biodiversity, environmental impact assessment technique must be capable of accurately assessing potential impact from flora and fauna and to entire ecosystem. Korea needs improvement of its assessment technique that is compatible with Korean environmental regulatory standard that is generally stricter than that of most countries. This study attempts to explore both domestic and overseas biodiversity assessment techniques and analyze each stage of environmental impact assessment. The data is collected from numbers of literatures selected by navigating both domestic and overseas literature database with certain keywords. Among the 44 selected papers, overseas publications outnumber those of domestics, and there are more researches on assessment methodology of biodiversity than assessment tool and model. In terms of environmental impact assessment, the number of papers on environmental impact forecast exceeds the numbers of papers on current state of environment and the impact minimizing solution. Therefore, contents and trends of those researches in the different stages of environmental impact assessment discussed in this paper not only suggest potential impact on biodiversity and minimization solutions in detail, but is also a valuable resource particularly for biodiversity relevant environmental assessment technique improvement in Korea. Proposing of a new direction of improvement in biodiversity assessment techniques makes this study significant, and further research for preservation of biodiversity should follow up to provide an improvement scheme for biodiversity assessment techniques in the future.

• The Journal of Korean Physical Therapy
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• v.19 no.1
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• pp.33-44
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• 2007

Purpose: To investigate and analyze effects of environmental enrichment(EE) and nerve stimulation that follows in application times with change of functional recovery(1, 3, 7 and 14 days). Methods: Focal ischemic brain injury was produced in 100 Sprauge-Dawley rats through middle cerebral artery occlusion(MCAO). Neurobehavioral assessment were selected, such as tilting plane testing, horizontal wire testing, vestibulomotor function testing and complex neuromotor function test, then they were randomly divided into five groups; Group I : Sham group, Group II: MCAO group, Group III: MCAO and ES group, Group IV: MCAO and EE group, Group V: MCAO and EE and ES group. Results: In neurobehavioral assessment, group V were significantly difference from other groups on between-subject effects. Conclusion: Our findings suggest that in focal ishemic brain injury, combined environmental enrichment and peripheral nerve electrical stimulation is more improved that the improvement of exercise function recovery than non treatment group.