• Journal of the Korean Society for Railway
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• v.12 no.6
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• pp.1043-1048
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• 2009

PES (Programmable Electronic System) is used by software development for the train control system. PES has been widely used in real world and consists of hardware, firmware and application software. The PES are easily apply to many applications because its implementation has high flexibility. Many safety critical functions are realized through software in safety critical system. Normally, it is difficult to detect failures for PES system because the PES is too sophisticated to identify sources of the failure. So, the reliability analysis is needed by using software fault tolerance techniques. Currently, there are the recovery block, distributed recovery block, N-version programming, N self-checking programming in fault tolerance techniques. In this paper, the models of recovery block and N-version programming in software fault tolerance techniques are suggested by using the Markov model. Also, the reliability in the train control system is analyzed through changing time. The fault occupancy rates of the program, adjustment test and voter are stationary. So, the relation between time and reliability is presented by using Matlab program. In the result of reliability, the reliability of recovery block is more high than N-version programming in case of the same number of substitution block.

• JSTS:Journal of Semiconductor Technology and Science
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• v.12 no.3
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• pp.341-352
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• 2012

This paper presents a Processing Engine (PE) which is used in Low Density Parity Codec (LDPC) application with a novel charge-recovery logic called pseudo-NMOS boost logic (pNBL), to achieve high-speed and low power dissipation. pNBL is a high-overdriven and low area consuming charge recovery logic, which belongs to boost logic family. Proposed Processing Engine is used in LDPC circuit to reduce operating power dissipation and increase the processing speed. To demonstrate the performance of proposed PE, a test chip is designed and fabricated with 0.18 2m CMOS technology. Simulation results indicate that proposed PE with pNBL dissipates only 1 pJ/cycle when working at the frequency of 403 MHz, which is only 36% of PE with the conventional static CMOS gates. The measurement results show that the test chip can work as high as 609 MHz with the energy dissipation of 2.1 pJ/cycle.

• Resources Recycling
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• v.8 no.4
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• pp.57-63
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• 1999

Wood-Polymer Composites (WPC) m s prepared irom recycled films of agricullural use and wood wastes, and LLDPE and neal PE resin mlxlurr war also utilized in order to cornpiue the praperlies. Molc~ca nhydride (MA) and dicumyl peroxide were used as an adheslon pmmoler and an il~lliatotor~, .espcmivelyT. ensile prapenies of W Cw zrc measured via lenslle test as a funclieu of woad lille~m d MA contmt, and rractu1.e surface was also mvestigaled wilh SEM. As the content of wwd tiller mcreased, clongauon deneased bul modulus increased However, tensile slrength OI WPC increased only when MA war used, and 1 wt.% of MA may be hgh enough to increase the tensile properties. The tensilc ptopcrlies af WPC prepwed from recycled PE films were &nost same as thosc of neal PE resin mixture.

• Membrane Journal
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• v.23 no.1
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• pp.45-53
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• 2013

Membrane filtration processes are increasingly popular for drinking water treatment that requires high quality of water. But pre-treatment system (Coagulation/Flocculation/Sedimentation) requires increased footprint and installation cost. In addition, 5~10% of the concentrate are formed. In this study, the pressurized PVDF membrane (ECONITY Co., Ltd.) system was tested with surface water (Han River, South Korea) without pre-treatment. As a result, permeate flux was operated between 1 m/d and 2.4 m/d (at $25^{\circ}C$) without chemical cleaning for one year and membrane permeate turbidity was maintained stably under 0.05 NTU regardless of raw water turbidity. And we studied application of concetrate treatment of pressurized PVDF membrane by submerged PE membrane (ECONITY Co., Ltd.). As a result, we increased recovery of total treatment process to 99.5%.

• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.1042-1046
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• 1998

A new soft switching isolated bi-directional phase shifted pulse width modulation (PSPWM) dc/dc converter is presented. Due to the use of the energy recovery snubber, the isolated bi-directional PSPWM dc/dc converter has a significant reduction of switching losses in the switching devices of the primary and secondary side bridge, respectively. The proposed soft switching bi-directional PSPWM FB dc/dc converter provides an energy recovery snubber which consists of two fast recovery diodes, a resonant capacitor and a resonant inductor. The complete operating principles and simulation results will be presented.

• Membrane Journal
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• v.22 no.1
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• pp.46-53
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• 2012

Low-temperature carbon dioxide stripping by a vacuum membrane stripping technology was studied as a substitute for the stripping process in a conventional aqueous amine process. Composite membranes with $5{\mu}m$ thickness of PDMS (polydimethylsiloxane) dense layer on a PE (polyethylene) support layer were prepared by a casting method and used as a membrane contactor for $CO_2$ stripping. Aqueous amine solutions of 30 wt% MEA (monoethanolamine) were used as absorbents. $CO_2$ flux was examined under various operating conditions by varying the vacuum pressure (60~360 mmHg (abs.)), stripping temperature ($25{\sim}80^{\circ}C$), $CO_2$ loading (0.5~0.7). $CO_2$ stripping flux increased with increasing temperature and $CO_2$ loading as well as decreasing vacuum pressure. PDMS-PE composite membrane has stability for vacuum stripping process compared with PTFE porous membrane.

• Smart Structures and Systems
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• v.25 no.3
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• pp.337-343
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• 2020

In this paper, we focused on the self-healing concrete using new nano-capsules. Three types of nano-capsules with respect to availability, high strength and temperature tolerance are used; type 1 is URF and polyethylene (PE) as shell and nano titanium oxide (TiO₂) as core, type 2 is URF and PE as shell and nano silica oxide (SiO₂) as core, type 3 is PE as shell and nano silica oxide (SiO₂) as core. The concrete samples mixed by nano-capsules with three percents of 0.5, 1 and 1.5. Based on experimental tests and the compressive strength of samples, the URF-PE-SiO₂ is selected for additional tests of compressive strength before and after recovery, ultrasonic test, ion chlorine and water penetration depths. After careful investigation, it is concluded that the optimum value of URF-PE-SiO₂ nano-capsules is 0.5% since leads to higher compressive strength, ultrasonic test, ion chlorine and water penetration depths.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.2235-2245
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• 2016

Ulcerative colitis (UC) results from colonic epithelial barrier defects and impaired mucosal immune responses. In this study, we aimed to investigate the modifying effects of a Spirogyra neglecta extract (SNE), a polysaccharide extract (PE) and a chloroform fraction (CF) on dextran sodium sulfate (DSS)-induced colitis in mice and to determine the mechanisms. To induce colitis, ICR mice received 3% DSS in their drinking water for 7 days. Seven days preceding the DSS treatment, oral administration of SNE, PE and CF at doses of 50, 25 and 0.25 mg/kg body weight (low dose), 200, 100 and 1 mg/kg body weight (high dose) and vehicle was started and continued for 14 days. Histologic findings showed that DSS-induced damage of colonic epithelial structure and inflammation was attenuated in mice pre-treated with SNE, PE and CF. Furthermore, SNE and PE significantly protected colonic epithelial cells from DSS-induced cell cycle arrest, while SNE, PE and CF significantly diminished apoptosis. Proteome analysis demonstrated that SNE and PE might ameliorate DSS-induced colitis by inducing antioxidant enzymes, restoring impaired mitochondria function, and regulating inflammatory cytokines, proliferation and apoptosis. These results suggest that SNE and PE could prevent DSS-induced colitis in ICR mice by protection against and/or aiding recovery from damage to the colonic epithelium, reducing ROS and maintaining normal mitochondrial function and apoptosis.

• The Journal of Korean Medicine
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• v.19 no.2
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• pp.228-243
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• 1998

This study was undertaken to evaluate the effect of Sunghyangchungisan (SHCS) on the regulation of vascular tone. Vascular rings isolated from rabbit carotid artery were myographed isometrically in isolated organ baths and the effect of SHCS on contractile activities were determined. SHCS relaxed the arterial rings which were pre-contracted by phenylephrine(PE). The responses to SHCS were partially dose-dependent at concentrations lower than 0.5 mg/ml. When SHCS was applied prior to the exposure to PE, it inhibited the PE-induced contraction by a similar magnitude which was comparable to the relaxation of pre-contracted arterial rings. Washout of SHCS after observing its relaxant effect resulted in a full recovery of PE-induced contractions, indicating that the action mechanism is reversible. The observation that SHCS did not change the $ED_{50}$ of PE on its dose-response curve ruled out the possible interaction of SHCS and ${\alpha}-receptor$. The relaxant effect of SHCS was not affected by removal of endothelium, and pretreatment of the arterial rings with methylene blue or nitro-L-arginine. This results suggest that the action of SHCS is not mediated by endothelium nor soluble guanylate cyclase. SHCS relaxed high $K^{+}-induced$ contractions as well, whereas it failed to relax phorbol ester-induced contractions. When contraction was induced by additive application of $Ca^{2+}$ in arterial rings which were pre-depolarized by high $K^+$ in a $Ca^{2+}-free$ solution, the relaxant effect of SHCS was attenuated by increasing the $Ca^{2+}$ concentration. SHCS, when applied to the arterial rings pre-contracted by PE and then relaxed by nifedipine, a $Ca^{2+}$ channel blocker, did not show additive relaxation. From above results, it is suggested that SHCS relax PE-induced contraction of rabbit carotid artery in an endothelium-independent manner, and inhibition of $Ca^{2+}$ influx may contribute to the underling mechanism.

• Analytical Science and Technology
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• v.18 no.1
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• pp.13-22
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• 2005

The elution patterns of seventeen 2,3,7,8-substituted PCDDs/Fs and 12 dioxin-like PCBs were studied by both manual open columns and automatic parallel LC columns in cleanup procedure. PCDDs/Fs and non-ortho-PCBs from other mono-ortho-PCBs were separated on automatic LC column, whereas they were not separated on an open manual column. The elution study on two cleanup methods was carried out using the PAR solution of unlabeled congeners and checked the recovery of each congener. Total recoveries of cleanup fractionation were ranged between 61.9 ~ 96.0% for PCDDs/Fs and 70.4 ~ 79.0% for PCBs by manual open columns and 71.8 ~ 104.5% for PCDDs/Fs and 61.3-120.3% for PCBs by automatic parallel LC columns, respectively. Unfortunately, #169-HxCB and 1,2,3,7,8-PeCDD were not separated on DB-5MS capillary column. The ions of 1,2,3,7,8-PeCDD were selected at M/M+2 instead of M+2/M+4 suggested by EPA method 1613. It is possible to discriminate 1,2,3,7,8-PeCDD and PCB #169 in HRGC/HRMS analysis.