• Journal of the Korean Society for Advanced Composite Structures
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• v.4 no.2
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• pp.25-30
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• 2013

In this study a hybrid safety barrier system consisting of steel rail and carbon fiber reinforced polymer (CFRP) post is considered. W hile CFRP post is selected for impact energy reflection due to its high strength, steel rail is selected for impact energy absorption due to its high ductility. A numerical model considering the elastoplastic behavior of steel is formulated to simulate the dynamic responses of the hybrid system subject to an impact load. A hybrid roadside guard rail system of steel rail and CFRP post is proposed and analyzed with a case study. The numerical model for the hybrid roadside guard rail system is used to find optimized design of the proposed hybrid system.

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.5
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• pp.485-495
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• 2000

The parallel computer system that uses parallel program on the application such as a large scale business or complex operation is required. One of crucial operation of parallel computer system is synchronization. A representative method of synchronization is barrier synchronization. A barrier forces all process to wait until all the process reach the barrier and then releases all of the processes. There are software schemes, hardware scheme, or combinations of these mechanism to achieve barrier synchronization which tends to use hardware scheme. Besides, barrier synchronization lets parallel computer system fast because it has fewer start-up overhead. In this paper, we propose a new switch module that can implement fast and fault-tolerant barrier synchronization in hardware scheme. A proposed barrier synchronization is operated not in full-switch-driven method but in processor-driven method. An effective barrier synchronization is executed with inexpensive hardware supports. Therefore, a new proposed hardware barrier synchronization is designed that it is operated in arbitrary network topology. In this paper, we only show comparison of barrier synchronization on Multistage Interconnection Network. This research results in 24.6-24.8% reduced average delay. Through this result, we can expect lower average delay in irregular network.

• The Journal of the Acoustical Society of Korea
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• v.30 no.1
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• pp.42-48
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• 2011

This preliminary study is about the application of the compound source to the active noise barrier system as control sources. A compound source is composed of two monopole sources but having opposite phase. However, both monopole sources in one compound source are not independently controlled. The source strength of monopole source close to the noise source is proportional to the other one. Therefore, the cost for the hardware system is cheaper than usual system but known to possibly having a similar performance in generating anti-noise acoustic field. In this study, using a simple active noise barrier system model having a non-reflective floor, the effectiveness of the system with compound sources is investigated through computer simulations and shows 30~40 % performance improvement of noise reduction.

• Korean System Dynamics Review
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• v.14 no.4
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• pp.143-163
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• 2013

This study is firstly aiming at diagnosing the present problems of evaluating the performance, especially in the field of disaster and safety management, of LGA (Local Government Authorities) in Korea. The study also deals with developing alternatives to solve a series of barrier factors revealed during the evaluation process using System Dynamics. This paper therefore presents literature review including the official documents published by the government and the performance evaluation studies of LGA. Moreover the authors analyze the current practice of the CELG (Combined Evaluation of Local Governments) as performance management, address and map a series of barrier factors in the CELG process to elaborate the CLDs (Causal-Loop Diagrams) and find solutions using system thinking with the CLDs. According to the analysis results, the core barrier factors to overcome is lack of proactive indicators/indices in the current practice of the CLEG. The authors therefore recommend to develop more proactive indicators that leads to avoid difficulties in measuring the LGA output, as well as to lessen the burden in competition for rankings and goal of the displaced.

• Korean Journal of Optics and Photonics
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• v.20 no.2
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• pp.102-109
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• 2009

In this paper, we introduce an eye-tracking 3D display system using variable parallax barrier and DDC communication. A barrier of variable parallax barrier composed of 4 sub-barriers and a commercially available web camera is utilized to implement the eye-tracking system. The coordinates of a viewer is extracted from the web camera transfer to 3D display via DDD/CI communication. The variable barrier attached to the LCD moves electrically according to the right eye position for 3D images. This system is compared experimentally with the commercial parallax barrier methods.

• Journal of the Korean Geosynthetics Society
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• v.19 no.4
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• pp.1-9
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• 2020

This study analyzes contaminant movement under transient flow in a rubble mound revetment offshore waste landfill barrier system that prevents contaminant runoff. The barrier system consists of bottom layer and side barrier. For the bottom layer system, impermeable clay layer is used. For the side barrier system, the HDPE barrier sheet (primary element) plays the main role, and the intermediate protection layer (supplementary element) is responsible for the barrier. Seepage, advection, dispersion numerical analysis was carried out using SEEP / W and CTRAN / W programs. As a result, under abnormal conditions considering the fluctuation in tidal range, the volume and direction of the flow velocity vector of the pore water change with time and the dispersion concentration of the contaminant changes. When comparing the case of 2 m tidal range and 8 m tidal range, the larger the tide value, the higher the concentration of contaminant under abnormal conditions. It was found that the rate of change of the concentration of the contaminant changed depending on the change in the tidal range, and as a result, the outflow of the pollutant was smaller than that in the steady flow state.

• Journal of Microbiology and Biotechnology
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• v.32 no.7
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• pp.825-834
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• 2022

Inflammatory bowel disease (IBD) is a global disease that is in increasing incidence. The gut, which contains the largest amount of lymphoid tissue in the human body, as well as a wide range of nervous system components, is integral in ensuring intestinal homeostasis and function. By interacting with gut microbiota, immune cells, and the enteric nervous system, the intestinal barrier, which is a solid barrier, protects the intestinal tract from the external environment, thereby maintaining homeostasis throughout the body. Destruction of the intestinal barrier is referred to as developing a "leaky gut," which causes a series of changes relating to the occurrence of IBD. Changes in the interactions between the intestinal barrier and gut microbiota are particularly crucial in the development of IBD. Exploring the leaky gut and its interaction with the gut microbiota, immune cells, and the neuroimmune system may help further explain the pathogenesis of IBD and provide potential therapeutic methods for future use.

• The Journal of Pediatrics of Korean Medicine
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• v.37 no.4
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• pp.53-62
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• 2023

Objectives The aim of this study was to identify the effect of Baekho-tang extract on epidermal barrier recovery and inflammation relief in atopic dermatitis-induced mice through Endocanabinoid system (ECS) regulation. Methods In this study, we used 4-week-old NC/Nga mice were divided into 4 group: lipid barrier elimination group (LBEG), palmitoylethanolamide treated group after lipid barrier elimination (PEAT), Baekho-tang extract treatment group after lipid barrier elimination (BHTT) and control group (Ctrl). Each group was assigned 10 animals. We identified that cannabinoid receptor (CB) 1, CB2, CD (Cluster of Differentiation) 68, inducible nitric oxide synthase (iNOS), substance P and Matrix metallopeptidase 9 (MMP-9) through our immunohistochemistry. Results We discovered that when compared to PEAT, 8-hydroxydeoxyguanosine, a marker of oxidative stress in the epidermal barrier, and CB1 and CB2, markers of ECS modulation, were less activated in BHTT. These results led to an anti-inflammatory response in BHTT, with a significant decrease in several inflammatory mediators such as CD 68, iNOS, substance P and MMP-9 compared to PEAT and LBEG. Conclusions These results suggest that the Baekho-tang extract can reduce the inflammation of atopic dermatitis by restoring the structural damage of the skin lipid barrier through ECS modulation.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.6
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• pp.76-81
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• 2021

A plastic noise barrier is a structure installed to minimize noise, and it is composed of the main plate, sound-absorbing plate, and sound-absorbing material. Plastic noise barrier structures have several advantages compared to other products, such as light weight, anticorrosion, durability, easy assembly, rapid construction, and low costs. In this study, the main and sound-absorbing plates were manufactured through extrusion molding, and the sound-absorbing plate was finished with a press to improve the conventional injection molding. Extrusion molding dies and punch dies were designed, and a profile extrusion-molding system was developed. Thus, inexpensive and efficient sound-absorbing and main plates can be produced, and the noise barrier structure can be assembled rapidly. Additionally, a noise barrier structure with extended service life and excellent quality can be constructed by creating uniform free space to accommodate increased temperatures after assembly and installation.

• Proceedings of the KSEEG Conference
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• 2007.04a
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• pp.256-256
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• 2007