• Sleep Medicine and Psychophysiology
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• v.3 no.1
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• pp.38-46
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• 1996

The purpose of this study is to investigate the neurocognitive dysfunction and the degree of severity according to the oxygen desaturation in obstructive sleep apnea patients. We performed nocturnal polysomnographic recording and administered 3 Vienna Test System subtest of Reaction unit, Continuous attention and Cognitrone to 11 obstructive sleep patients and 13 controls. The result were as follows: 1) On Continous attentin and Cognitrone, patients with obstructive sleep apnea showed significant lower score on correct answer, higher score on missed answer and prolonged reaction time than control. But, there was no significant difference on Reaction unit between two groups. 2) Among 3 groups divided by degree of oxygen desaturation, there were no significant differences on Reaction unit. As the oxygen saturation decreased however, the obstructive sleep apnea group revealed significantly poor performance score on continuous attention and cognitrone. We suggested that obstructive sleep apnea patients showed disturbed neurocognitive function with complex cognitive process and the severity of neurocognitive dysfunction was also correlated with oxygen desaturation.

• Geomechanics and Engineering
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• v.8 no.2
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• pp.187-220
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• 2015

Soil disturbance induced by installation of mandrel driven vertical drains decreases the in situ horizontal hydraulic conductivity of the soil in the vicinity of the drains, decelerating the consolidation rate. According to available literature, several different profiles for the hydraulic conductivity variation with the radial distance from the vertical drain, influencing the excess pore water pressure dissipation rate, have been identified. In addition, it is well known that the visco-plastic properties of the soil also influence the excess pore water pressure dissipation rate and consequently the settlement rate. In this study, a numerical solution adopting an elastic visco-plastic model with nonlinear creep function incorporated in the consolidation equations has been developed to investigate the effects of disturbed zone properties on the time dependent behaviour of soft soil deposits improved with vertical drains and preloading. The employed elastic visco-plastic model is based on the framework of the modified Cam-Clay model capturing soil creep during excess pore water pressure dissipation. Besides, nonlinear variations of creep coefficient with stress and time and permeability variations during the consolidation process are considered. The predicted results have been compared with V$\ddot{a}$sby test fill measurements. According to the results, different variations of the hydraulic conductivity profile in the disturbed zone result in varying excess pore water pressure dissipation rate and consequently varying the effective vertical stresses in the soil profile. Thus, the creep coefficient and the creep strain limit are notably influenced resulting in significant changes in the predicted settlement rate.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.3 no.1
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• pp.70-79
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• 2000

Arbuscular mycorrhizal(AM) fungi have significant role for ecosystem structure and function. They are the major component of forest soil ecosystems and critically important for water and nutrient cycling in the system. To understand the ecology of AM fungi the fungal spores were collected, identified and counted in forest soils under various climatic and edaphic conditions. In relation to soil depth 90% of AM fungi spores and mycorrhizas distributed within 15cm soil depth. Number of spores per $100m{\ell}$ forest soil volume was 5 to 36 spores from 1 to 3 fungal species. AM fungal species diversity was higher in warmer climates, and more moist and fertile soils. The most frequently found species were Gigaspora decipiens irrespective of soil moisture and Gi. gigantea irrespective of soil fertility. In the Jeju island the soils of Cryptomeria japonica plantations and Miscanthus sinensis var. purpurascens meadow had more AM spores than the other soils. We suggest AM fungi be considered as keystones species when restoring a disturbed forest ecosystem.

• Advances in Traditional Medicine
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• v.9 no.1
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• pp.39-48
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• 2009

We have evaluated the effect of long term treatment of Enicostemma littorale (E. littorale) in type 2 diabetic patients taking pills of aqueous extract of E. littorale regularly as a complimentary medicine for at least 9 months. The effects of E. littorale on glycemic control, lipid profile, cardiac function and DNA damage in these patients were compared with those who had not been regular in taking E. littorale but regular in taking other conventional anti-diabetics. Our data suggest that, E. littorale can maintain normal blood glucose, serum insulin, serum triglycerides levels of type 2 diabetic patients if taken regularly. E. littorale also improves insulin sensitivity, and normalize disturbed lipogram and elevated creatinine levels, thereby produces beneficial effect in preventing cardiovascular complications and may preserve the kidney function. The finding that E. littorale also prevents DNA damage suggest a long term effect in diabetic patients. E. littorale thus can be considered as safe supplementary therapy for a long term and effective management of type 2 diabetic patients.

• Journal of Marine Bioscience and Biotechnology
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• v.4 no.1
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• pp.31-34
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• 2010

The primary function of the skin is to protect the body from the unwanted environmental influences. The outermost layer of the skin is stratum corneum which consists of corneocytes surrounded by lipid regions. Ceramides covalently bound to keratinocytes are essential for the barrier function of the skin, which can be disturbed in the disease, like xerosis. Xerosis is an abnormal dryness of the skin which reduced the thickness of stratum corneum and ceramide content decreasing with age. In this study, 36 seaweed extracts have been tested for screening of xerosis inhibitory agent by in vitro HaCaT keratinocyte assay. Ishige sinicola and Helminthocladia australis induced the significant amount of ceramide-like substance I in HaCaT keratinocyte among the tested seaweed extracts. Sargassum fulvellum, Chondrus ecellatus and Gigartina tenella also induced the ceramide-like substance I whereas Helminthocladia australis and Pachymeniopsis elliptica induced the ceramide-like II from HaCaT keratinocyte.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.783-786
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• 2015

Hole attack, which is disturbed transmission function through change of routing information, can cause critical results for MANET as non-infrastructure network. Backhole attack, as a typical hole attack, is one malicious attack which is disabled network transmission function by assumption of transmission data through modification of routing information. It is very important to evaluate transmission performance caused by blackhole attack, because transmission performance of MANET is affective with blackhole attack. In this paper, transmission performance is analyzed with MANET under multiple blackhole attacks caused multiple blackhole nodes. Computer simulation based on NS-2 is used as analysis tool and voice traffic is considered ad application service on MANET.

• International Journal of Concrete Structures and Materials
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• v.6 no.3
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• pp.135-144
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• 2012

This article reviews the tailoring of engineered cementitious composites (ECC), a type of high performance fiber reinforced cementitious composites with a theoretical design basis, for special attributes or functions. The design basis, a set of analytic tools built on micromechanics, provides guidelines for tailoring of fiber, matrix, and fiber/matrix interfaces to attain tensile ductility in ECC. If conditions for controlled multiple cracking are disturbed by the need to introduce ingredients to attain a special attribute or function, micromechanics then serve as a systematic and rational means to efficiently recover composite tensile ductility. Three examples of ECCs with attributes of lightweight, high early strength, and self-healing functions, are used to illustrate these tailoring concepts. The fundamental approach, however, is broadly applicable to a wide variety of ECCs designed for targeted fresh and/or hardened characteristics required for specific applications.

• Journal of Positioning, Navigation, and Timing
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• v.8 no.4
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• pp.225-232
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• 2019

The satellite-based ionospheric model consists of local first-order plane function parameters for individual satellites and provides excellent accuracy in the flat ionospheric environment of the Korean Peninsula. This paper analyzes the performance of such model under the rapid changes in the ionosphere. Rapid changes in the ionosphere were observed in Korea from September to October 2014, and a satellite-based ionosphere model was applied to Wide Area Differential GPS (WADGPS) to analyze the navigation performance and the performance of estimating ionospheric delay errors. After processing the test data, it was confirmed that there was a deterioration in navigation performance and extrapolation performance in low-latitude areas and analyzed the cause.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.8
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• pp.727-734
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• 2010

This paper deals with an anti-sway control for a ship-mounted container crane which is disturbed by the wave-induced motions of the ship. We derive a simple dynamics of the ship-mounted container crane with an active anti-sway control system and transform it into a dynamic function for a horizontal variable on the absolute coordinate. Then we propose an control method to reduce pendulation of the spreader and compare its performance with well-known feedback linearization control in computer simulation.

• Management Science and Financial Engineering
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• v.12 no.2
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• pp.19-35
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• 2006

We use the hierarchical Bayesian approach to describe the transition probabilities of a binary nonhomogeneous Markov chain. The Markov chain is used for describing the transition behavior of emotionally disturbed children in a treatment program. The effects of covariates on transition probabilities are assessed using a logit link function. To describe the time evolution of transition probabilities, we consider two modeling strategies. The first strategy is based on the concept of exchangeabiligy, whereas the second one is based on a first order Markov property. The deviance information criterion (DIC) measure is used to compare models with two different time dependent structures. The inferences are made using the Markov chain Monte Carlo technique. The developed methodology is applied to some real data.