• Journal of Korean Society of Coastal and Ocean Engineers
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• v.16 no.1
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• pp.1-9
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• 2004

In this study, several new types of floating breakwater are proposed according to the geometry of the vertical barrier and the existence of horizontal plate, and are compared to the steel floating breakwater adopted in Won-Jun fishing port and the performance of wave control is numerically investigated by using Green function method. From the numerical results, model attached the horizontal barrier under the vertical barrier is more efficient for reflection and transmission coefficient than the steel floating breakwater in Won-Jun fishing port. It is confirmed that the transmitted waves can be controlled efficiently by optimizing the length and distance of a vertical and horizontal barriers.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.22 no.2
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• pp.105-115
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• 2024

In this study, we employed a small-scale experiment to demonstrate the introduction of a thin copper heat dissipation plate into a bentonite buffer layer of an engineered barrier system. This experiment designed for spent nuclear fuel disposal can effectively reduce the maximum temperature of the bentonite buffer layer, and ultimately, make it possible to reduce the area of the disposal site. For the experiment, a small-scale engineered barrier system with a copper heat dissipation plate was designed and manufactured. the thickness of the cylindrical buffer was about 2 cm, which was about 1/20 of KAERI Repository System (KRS). At a power supply of 250 W, the maximum buffer temperature reduced to a mere 1.8℃ when the thin copper plate was introduced. However, the maximum surface temperature reduced to a remarkable 9.1℃, when a U-collar copper plate was introduced, which had a good contact with the other barrier layers. Consequently, we conclude that the introduction of the thin copper plate into the engineered barrier system for spent nuclear fuel disposal can effectively reduce the maximum buffer temperature in high-level radioactive waste disposal repositories.

• Journal of Auto-vehicle Safety Association
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• v.6 no.2
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• pp.55-60
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• 2014

To verify the performance of roadside safety facilities, strength and occupant protection test are performed by evaluation criteria. Strength test use a truck and occupant protection test use a sedan. Strength perfomance is analyzed pass rate by post lateral resistance of the safety barrier. Occupant protection performance is analyzed from THIV(Theoretical Head Impact Velocity) and PHD(Post-impact Head Deceleration) by crash cushion test.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.1081-1085
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• 2002

A modeling is developed to predict the isolation performance of sound barrier systems under the sound pressure radiated from excited by point impact. The predicted results are compared with the measured results obtained by using APAMAT II. This instrument provides a combination of structure-borne noise and air-borne noise, which corresponds to rolling noise, by applying the excitation system projected steel balls against the steel sheet.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.27-28
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• 2021

For Barrier-Free certification, the floor and ground surfaces must be finished with materials that are not slippery, flat, and have low-impact in fallis. However, the BF Certification Act does not provide specific methods to meet these regulations. In performance-based design, the responsibility of proving the performance rests with the building owner and architect, so quantitative evaluation indexes are needed to select suitable materials. Furthermore, changes in performance after completion should be checked periodically in 'As-Is' conditions. There are various methods for slips, trips and falls risk assessment, causing confusion for users. In this study, the results of previous studies on the evaluation methods of slips, trips and falls were considered closely, and each quantitative evaluation index that can be used in the new construction and maintenance phase was presented.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.7
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• pp.1156-1166
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• 2020

Objective: The aim of this study was to evaluate the effects of compound organic acid calcium (COAC) on growth performance, hepatic antioxidant status and intestinal barrier of male broilers under high ambient temperature (32.7℃). Methods: Nine hundred healthy one-d-old Cobb-500 male broiler chicks were randomly assigned into three groups with six replicates of 50 birds each. A basal diet supplemented with 0% (control), 0.4% and 0.8% COAC, respectively were fed to birds for 6 weeks. All treatments were under high ambient indoor temperature of 32.7℃, and had a constant calcium and available phosphorus ratio. Results: The results showed that, compared with control, the average daily gain of broilers in 0.4% and 0.8% was significantly increased and the ratio of feed to gain in in 0.4% and 0.8% was significantly decreased at 1 to 21, 22 to 42 and 1 to 42 days of age (p<0.05). Compared with control, 0.8% COAC slightly decreased (p = 0.093) the content of malondialdehyde in liver at 42 days of age while 0.4% COAC significantly decreased (p<0.05) the activity of alkaline phosphatase. Furthermore, 0.4% COAC significantly enhanced the intestinal barrier function via increasing jejunal and ileal ocln transcription, promoting jejunal mucin 2 transcription at 42 days of age (p<0.05), and decreasing jejunal toll-like receptor 2 (TLR-2) and ileal TLR-15, inducible nitric oxide synthase compared with control group (p<0.05). Whereas, no significant differences on the transcription of interleukin-1β in jejunum and ileum were observed among three treatments (p>0.05). Overall, heat stress caused by high natural environment temperature may induce the damage to hepatic antioxidation and intestinal barrier. Conclusion: Dietary inclusion of COAC can improve the tolerance of broilers to thermal environment through the modification of antioxidative parameters in liver and the mRNA expression of genes in intestinal barrier, resulting in an optimal inclusion level of 0.4%.

• The Korean Journal of Health Service Management
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• v.1 no.1
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• pp.75-89
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• 2007

The start point of a franchise system such as Lotteria was in 1979. Since 1990, the franchise systems in Korea have rapidly spread over all industry types. As 'Franchise Law' was enforced in 2002, the expansion of a franchise picked up its' speed. The barbers and beauty parlors business has the same expansion trend. However, there was no study about the franchise systems in the barbers and beauty parlors business. The purpose of this study was to find the goodness of fit of the structured equation model proposed and identify the significances of relationships in the variables of justice perceptions, trust, satisfactions, business performances, switching barriers, switching cost etc. This study tries to find a solution for a good development between franchisor and franchisee in the barbers and beauty parlors business in Korea. The theoretical considerations about justice of this study is limited in reciprocal relation justice and procedure justice. And it did make simplify for trust, satisfaction, business performance, switching barrier. And switching barrier did measure as dimension of switching coot. From October 26, 2005 to October 29, this study collected 250 survey questionnaires from the franchisees located in Seoul, Busan, Daegu, Ulsan, and Keoyng-Nam. In analyses of using SPSS Windows 11.0 and LISREL 8.14, this study used 208 cases because 48 cases did not response appropriately. Tn conclusions. reciprocal justice perception and procedure justice jointly determined trust. Secondly, reciprocal justice perception significantly determined satisfaction. Procedure justice perception negatively determined satisfaction, but this relationship was not significant. Thirdly, reciprocal justice perception positively influenced business performance, and procedure justice negatively influenced business performance, but the last relationship was not significant Fourthly, trust positively significantly influenced satisfaction and business performance. Fifthly, satisfaction positively influenced business performance and true determined switching barrier positively. This study shows following: firstly, a composition concept did make structural relationship and secondly, a reciprocal relation justice of a franchisor did appear as an important variable and it gives positive influence to trust, satisfactions, business performance, switching barriers of the franchisees.

• Proceedings of the Acoustical Society of Korea Conference
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• 1984.12a
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• pp.45-45
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• 1984

• Proceedings of the Korean Nuclear Society Conference
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• 2003.10a
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• pp.488.1-488.1
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• 2003

• Journal of the Korean Society of Safety
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• v.31 no.2
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• pp.83-89
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• 2016

As the world's industrial development quickens, the highways and regional expressways have been expanding to serve the logistics and transportation needs of people. The burgeoning road construction has led to a growing interest in roadside installations. These must have reliable performance over long periods, reduced maintenance and high durability. Steel roadside barriers are prone to corrosion and other compromises to their functionality. Therefore, using high anti-corrosion steel material is now seen as a viable solution to this problem. Thus, the objective of this paper is to expand the scope of applications for high anti-corrosion steel material for roadside barriers. This paper assesses the impact safety such as structural performance, occupant protection performance and post-impact vehicular response performance by a simulation review on roadside barriers built with high strength anti-corrosion steel materials named as hot-dip zinc-aluminium-magnesium alloy-coated steel. The simulation test results for the roadside barriers built with high strength anti-corrosion steels with reduced sectional thickness meet the safety evaluation criteria, hence the proposed roadside barrier made by high strength and high anti-corrosion hot-dip zinc-aluminium-magnesium alloy-coated steel will be a good solution to serve safe impact performance as well as save maintenance cost.