• Restorative Dentistry and Endodontics
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• v.29 no.4
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• pp.353-364
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• 2004

The purpose of this study was to compare and to evaluate the combination use of 5 kinds of dentin adhesive systems and 5 kinds of composite resins using micro-shear bond test. Five adhesive systems (Prime & Bond NT (PBN). Onecoat bond (OC), Excite (EX), Syntac (SY), Clearfil SE bond (CS)) and five composite resins (Spectrum (SP), Synergy Compact (SC), Tetric Ceram (TC), Clearfil AP-X (CA), Z100 (Z1)) were used for this study ($5{\;}{\times}{\;}5{\;}={\;}25group$, n =14/group). The slices of horizontally sectioned human tooth were bonded with each bonding system and each composite resin, and tested by a micro-shear bond strength test. These results were analyzed statistically. The mean micro-shear bond strength of dentin adhesive systems were in order of CS (22.642 MPa), SY (18.368 MPa), EX (14.599 MPa). OC (13.702 MPa). PBN (12.762 MPa). The mean bond strength of self-etching primer system group (CS, SY) in dentin was higher than that of self-priming adhesive system groups (PBN, EX, OC) significantly (P<0.05). The mean bond strength of composite resins was in order of SP (19.008 MPa), CA (17.532 MPa). SC (15.787 MPa), TC (15.068 MPa). Z1 (14.678 MPa). Micro-shear bond strength of SP was stronger than those of other composite resins significantly (P < 0.05). And those of TC and Z1 were weaker than other composite resins significantly (P < 0.05). No difference was found in micro-shear bond strength of composite resin in self-etching primer adhesive system groups (CS, SY) statistically. However, there was significant difference of micro-shear bond strength of composite resin groups in self-priming adhesive systems group (PBN, EX, OC). The combination of composite resin and dentin adhesive system recommended by manufacturer did not represent positive correlation. It didn't seem to be a significant factor.

• Journal of Digestive Cancer Reports
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• v.9 no.1
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• pp.25-32
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• 2021

Since Endoscopic ultrasound (EUS) was introduced in the 1980s, EUS has evolved from a diagnostic tool to a therapeutic modality for patients with pancreatic neoplasms. Traditionally, treatment policy of pancreatic benign neoplasms (PBN) has been a dichotomous approach to observation or surgery. However, EUS guided treatment provides an alternative option with minimally invasiveness for patients with PBN. This review aimed to provide the role of EUS guided treatment for PBN.

• Biomolecules & Therapeutics
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• v.16 no.3
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• pp.179-183
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• 2008

In the present study, we examined the effects of several therapeutics of Alzheimer's disease, such as donepezil hydrochloride, tacrine and $\alpha$-phenyl-n-tert-butyl nitrone (PBN) on choline efflux from brain to circulating blood. The brain-to-blood efflux of [$^3H$]choline in rats was significantly inhibited by tacrine and PBN. Also the [$^3H$]choline efflux was reduced by tacrine and donepezil hydrochloride in the TR-BBB cells, in vitro the blood-brain barrier (BBB) model. These results suggest that these drugs may influence choline efflux transport from brain to blood and regulate the choline level in brain resulting in the increase of acetylcholine synthesis.

• Macromolecular Research
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• v.12 no.1
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• pp.94-99
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• 2004

We have performed Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC) studies on blends of poly(vinyl phenol) (PVPh) with poly(n-alkylene 2,6-naphthalates) containing alkylene units of different lengths. The results indicate that each poly(ethylene 2,6-naphthalate) (PEN) and poly(trimethylene 2,6-naphthalate) (PTN) blend with PVPh is immiscible or partially miscible, but blends of poly(butylene 2,6-naphthalate) (PBN) with PVPh are miscible over the whole range of compositions in the amorphous state. FTIR spectroscopic analysis confirmed that significant degree of intermolecular hydrogen bonding occurs between the PBN ester carbonyl groups and the PVPh hydroxyl groups. The large difference in the degree of mixing in these blend systems is described in terms of the effect that chain mobility has on the accessibility of the ester carbonyl functional groups toward the hydroxyl groups of PVPh, which in turn impacts the miscibility of these blends.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.268-270
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• 2013

It is well known that tire pattern design factors have a large influence on overall tire performance. In this paper, the basic study on the effects of tire pattern design factors on tire labeling performance has been carried out through experimental tests. The pass-by noise is affected by tire pattern design, by a maximum of 2.7dB(A), and the number of sipes gives large effects on PBN. The rolling resistance is also influenced, mostly by the number of longitudinal grooves and secondly the number of sipes. Finally, there is a weak correlation between PBN and RR when the pattern design factors are changed.

• Archives of Pharmacal Research
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• v.28 no.4
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• pp.443-450
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• 2005

In the present study, we have characterized the choline transport system and examined the influence of various amine drugs on the choline transporter using a conditionally immortalized rat brain capillary endothelial cell line (TR-BBB) in vitro. The cell-to-medium (C/M) ratio of $[^3{H}]choline$ in TR-BBB cells increased time-dependently. The initial uptake rate of $[^3{H}]choline$ was concentration-dependent with a Michaelis-Menten value, $K_{m}$, of $26.2\pm2.7{\mu}M$. The $[^3{H}]choline$ uptake into TR-BBB was $Na^{+}-independent$, but was membrane potential-dependent. The $[^3{H}]choline$ uptake was susceptible to inhibition by hemicholinium-3, and tetraethy-lammonium (TEA), which are organic cation transporter substrates. Also, the uptake of $[^3{H}]choline$ was competitively inhibited with $K_{i}$ values of $274 {\mu}M, 251 {\mu}M and 180 {\mu}M$ in the presence of donepezil hydrochloride, tacrine and $\alpha-phenyl-n-tert-butyl nitrone$ (PBN), respectively. These characteristics of choline transport are consistent with those of the organic cation transporter (OCT). OCT2 mRNA was expressed in TR-BBB cells, while the expression of OCT3 or choline transporter (CHT) was not detected. Accordingly, these results suggest that OCT2 is a candidate for choline transport at the BBB and may influence the BBB permeability of amine drugs.

• Journal of Advanced Navigation Technology
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• v.21 no.6
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• pp.544-548
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• 2017

The International Civil Aviation Organization is recommending the use of SBAS on all aircraft by 2025 to urge PBN implementation around the world. As part of this, Korea is also developing KASS, a Korean SBAS. ICAO grants authority to the host nation aviation authority in the certification and operation of SBAS. The KASS system will be verified after detailed system design, fabrication and installation. In this paper, flight test parameters are derived from the flight inspection regulations and the configuration of the on - board measurement equipment for measuring the parameters has been proposed.

• Journal of Environmental Science International
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• v.30 no.3
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• pp.257-266
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• 2021

This study explored measures to reduce noise applicable to Gimhae international airport centering on densely packed housing areas. Especially, as for measures to relieve noise damage on the densely packed housing areas in Gimhae-si, the noise reduction effect is expected to be doubled if the west runway (36L/18R) is used as the preferred runway for the 36 direction takeoff, as well as if the flight bypasses the densely packed housing areas by means of sophisticated navigation using the area navigation (RNAV) procedure based on performance-based navigation (PBN). Takeoff toward the south connects the flight path to the South Sea which has comparatively low noise impact, relieving noise damage on the densely packed housing areas (apartment complexes in Naeoe-dong of Gimhae-si, etc.) near the northern end of the runway. The operation of the runway displaced threshold is currently being implemented on the west runway (36L/18R) of Gimhae international airport. It has been found that swing landing in spring and summer when the wind blows from the south has a noise reduction effect on the noise sensitive areas at the side and end of the west runway (Gangdong-dong and Jukdong-dong of Gangseo-gu and Buram-dong of Gimhae-si, etc.).

• Journal of Positioning, Navigation, and Timing
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• v.12 no.4
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• pp.379-389
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• 2023

According to the Korea Urban Air Mobility (K-UAM) Concept of Operation (ConOps), the Global Navigation Satellite System (GNSS) is recommended as the primary navigation system and the performance specification will be implemented considering the standard of Performance Based Navigation (PBN). However, by taking into account the characteristics of an urban environment and the concurrent operations of multiple UAM aircraft, the current PBN standards for civil aviation seem difficult to be directly applied to an UAM aircraft. Therefore, by referring to technical documents published in the literature, this paper examines the feasibility of applying the proposed performance requirements to K-UAM, which follows the recommendation of navigation performance requirements for K-UAM. In accordance with the UAM ConOps, the UAM aircraft is anticipated to maintain low altitude during approach and landing phases. Subsequently, the navigation performance degradation could occur in the urban environment, and the primary degradation factor is identified as multipath error. For this reason, to ensure the safety and reliability of the K-UAM aircraft, it is necessary to analyze the degree of performance degradation related to the urban environment and then propose an alternative aid to enhance the navigation performance. To this end, the aim of this paper is to model the multipath effects of the GNSS in an urban environment and to carry out the simulation studies using the real GNSS datasets. Finally, the initial navigation performance requirement is proposed based on the results of the numerical simulation for the K-UAM.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.41-44
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• 2002

블렌딩이나 공중합체의 합성은 한가지 또는 모든 구성성분 고분자의 단점을 보완하면서 효과적인 물성 발현을 위해 연구되어 왔다. 특히 방향족 폴리에스테르계 고분자들 사이에서는 PET/PEN, PEN/PHN, PBT/PBN, 또는 PET/PBT 등의 공중합체가 보고되고 있다[1-3]. 한편, poly(trimethylene terephthalate)(PTT)는 최근 섬유로 방사되어 카펫, 의류 등으로 응용된 이후 PTT를 주성분으로 하는 bicomponent 멜트블로운 부직포[4], 염색[5] 등의 연구가 활발히 이루어지고 있다. (중략)