• Corrosion Science and Technology
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• v.12 no.4
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• pp.191-197
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• 2013

This study is the second stage of developing the corrosion control technical manual about unpainted weathering steel bridge with closed box girder structures. This paper contains selection of corrosive sealant to apply into crevice of upper flange, injecting test of sealant at mock-up equipment with various condition, evaluation of experiment result. Through the experiment of injection of sealants into crevice of mock-up equipment, it is proved that the tar sealant injecting corrosion control method is useful to protect corrosion at box girder upper flange corroded by remaning rain water with calcium chloride.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.2
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• pp.267-270
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• 2021

Long-term experiments have been conducted on two important safety issues: long-term durability of a concrete barrier with the steel reinforcements and gas generation from low-and intermediate-level wastes in an underground research tunnel of a radioactive waste disposal facility. The gas generation and microbial communities were monitored from waste packages (200 L and 320 L) containing simulated dry active wastes. In the concrete experiment, corrosion sensors were installed on the steel reinforcements which were embedded 10 cm below the surface of concrete in a concrete mock-up, and groundwater was fed into the mock-up at a pressure of 2.1 bars to accelerate groundwater infiltration. No clear evidence was observed with respect to corrosion initiation of the steel reinforcement for 4 years of operation. This is attributed to the high integrity and low hydraulic conductivity of the concrete. In the gas generation experiment, significant levels of gas generation were not measured for 4 years. These experiments are expected to be conducted for a period of more than 10 years.

• Nuclear Engineering and Technology
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• v.53 no.7
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• pp.2151-2161
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• 2021

Nuclear data (ND) sensitivity and uncertainty (S/U) quantification in shielding applications is performed using deterministic and probabilistic approaches. In this paper the validation of the newly developed deterministic program package ASUSD (ADVANTG + SUSD3D) is presented. ASUSD was developed with the aim of automating the process of ND S/U while retaining the computational efficiency of the deterministic approach to ND S/U analysis. The paper includes a detailed description of each of the programs contained within ASUSD, the computational workflow and validation results. ASUSD was validated on two shielding benchmark experiments from the Shielding Integral Benchmark Archive and Database (SINBAD) - the fission relevant ASPIS Iron 88 experiment and the fusion relevant Frascati Neutron Generator (FNG) Helium Cooled Pebble Bed (HCPB) Test Blanket Module (TBM) mock-up experiment. The validation process was performed in two stages. Firstly, the Denovo discrete ordinates transport solver was validated as a standalone solver. Secondly, the ASUSD program package as a whole was validated as a ND S/U analysis tool. Both stages of the validation process yielded excellent results, with a maximum difference of 17% in final uncertainties due to ND between ASUSD and the stochastic ND S/U approach. Based on these results, ASUSD has proven to be a user friendly and computationally efficient tool for deterministic ND S/U analysis of shielding geometries.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.801-806
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• 2001

In the latest, the construction period became the most important factor in the domestic building works because buildings is higher and larger gradually. Accordingly, cold-weathering concrete constructions are performed more and more. So, the demands of concrete quality management methods are increased in cold-weathering concrete constructions. In this study, the mock-up experiment was performed to correct input data in the kimpo H construction field. Using the results of this experiment, the method of temperature analysis was presented to prevent early aged freezing damage and to control thermal crack in this study.

• KIEAE Journal
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• v.16 no.3
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• pp.121-128
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• 2016

Purpose: The vacuum glazing should constantly retain the gap in vacuum state to maintain high thermal performance. To do so, pillars are used to prevent the glazing from clinging to each other by the atmospheric pressure and therefore surface of the vacuum glazing is consistently affected by residual stress. The vacuum glazing could be applied to curtain wall systems at spandrel area to fulfill a rigorous domestic standard on U-value of the external wall. However, this can lead to high glazing temperature increase by heat concentration at a back panel and finally thermal stress breakage. This study experimentally determined weakness of the vacuum glazing systems on the thermal stress breakage and investigated effect of the residual stress. Method: The experiment first built two scale-down mock-up facilities that replicate the spandrel area in curtain wall, and then installed single low-e glass and vacuum glazing respectively. The two mock-up facilities were exposed to outside to induce the thermal stress breakage. Result: The experiment showed that the temperature occurred the thermal stress breakage was $114.4^{\circ}C$ for the single low-e glass and $118.9^{\circ}C$ for the vacuum glazing respectively. The result also showed the vacuum glazing reached the critical point earlier than the single low-e glass, which means that the vacuum glazing has high potential to occur the thermal shock breakage. In addition, the small temperature difference between two glazing indicates that the residual stress scarcely affects breakage of the vacuum glazing.

• The Journal of the Acoustical Society of Korea
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• v.35 no.3
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• pp.223-233
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• 2016

Design of a vegetation type sound barrier was presented as a noise barrier on the boundary of neighborhood facilities including schools, and apartments. The suggested noise barrier is made of unit blocks that are to be formed by stacking over the wall structure containing the plant and soils in the blocks. The advantage of the vegetation noise barrier is to acquire not only sound absorptive effects of plants and soils, but also sound diffusive effect caused by the irregular surface of the barrier which could eventually mitigate the noise. First, the optimum size of the units to obtain the highest noise reduction was investigated using 1/10 scaled model experiment, and sound attenuation experiments were carried out using a 1/2 mock-up model which is 2 m high and 5 m long. Total 1,137 unit blocks were made of synthetic woods with the size of $10{\times}10{\times}9cm$. These unit blocks were installed on the both side of the 1/2 mock-up steel framed noise barrier. As a result, it was revealed that the block typed vegetation noise barrier has 7 dB higher insertion loss in comparison with the general plane noise barrier. Also, it was found that the appropriate size of unit blocks is $20{\times}20cm$ which has large effect of sound insertion loss.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1781-1788
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• 2008

This report is the result of a basic experiment done on a mock-up tunnel, of what happens to the ventilated flow and fire driven flow inside a railway tunnel as the current inside the tunnel changes when an anti-smoke or a radio frequency invert control is installed. The duct used in this experiment is 10m in length, 0.5m in height and 0.25m in width and made of acrylic. An anti-smoke system with a motor that can produce current of 10m/sec maximum in order to create ventilated flow, has been installed. A honeycomb has been installed at the entrance of the duct to create a current flow that exists in tunnels. In order to create a ventilated flow, a current of 4m/s, 6m/s and 8m/s were generated using the anti-smoke system, as the study of current developed. A Hot-wire(TSI) and Pressure sensor(ENDEVCO) was installed in the duct, 1m apart, as the measurement of current and pressure went on. The current and pressure were automatically measured through the Lap View program and PC; the current flow in the mock-up tunnel generated by the honeycomb has been analyzed the pressure distribution and pressure drop has been analyzed.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.1
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• pp.159-168
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• 2011

In this study, we find out the feasibility of self-consolidating concrete with EP nylon fiber. Three kinds of method were used; when length of nylon fiber is differed for the experiment to investigate usability of nylon fiber with enhanced performance by dispersing-agent coating in self-consolidating concrete, when mixing in other organic fibers (polypropylene, cellulose) and in case of Binary Blended and Ternary Blended concrete mixed with different types of mineral admixtures (blast-furnace slag and fly ash). Based on the results of the experiment described above, comparison was made on the basic properties and dynamic characteristics of general fiber reinforced concrete mixed with enhanced performance nylon fiber and SCC mixed with enhanced performance nylon fiber as a Mock-up test prior to the experiment of application to the actual structure. Considering characteristics and durability of the fresh and hardened self-compacting concrete, dynamic characteristics and durability were found to be more outstanding when using nylon fiber for the mineral admixtures used, dynamic characteristics and durability were found to be more outstanding when using blast-furnace slag.

• Journal of the Korean Solar Energy Society
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• v.27 no.3
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• pp.169-174
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• 2007

Building integrated photovoltaic(BIPV) system operates as a multi-functional building construction material. They not only produce electricity, but also are building integral components such as facade, roof, window and shading device. As PV modules function like building envelope in BIPV, combined thermal and PV performance should be simultaneously evaluated. This study is to establish basic Information for designing effective BIPV by discovering relations between temperature and generation capability through experiment when the PV module is used as roof material for houses. To do so, we established 3kW full scale mock-up model with real size house and attached an PV array by cutting in half. This is to assess temperature influence depending on whether there is a ventilation on the rear side of PV module or not.

• Journal of IKEEE
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• v.3 no.1 s.4
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• pp.101-108
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• 1999

In this paper, a real time diagnostic algorithm for estimating the impact location by loose parts is proposed. It is composed of two modules such as the alarm discrimination module (ADM) and the impact-location estimation module(IEM). First, ADM decides whether the detected signal that triggers the alarm is the impact signal by loose parts or the noise signal. Second, IEM by use of the arrival time method estimates the impact location of loose parts. In order to validate the application of this method, the test experiment with a mock-up (flat board and reactor) system is performed. The experimental results show the efficiency of this algorithm even under high level noise and potential application to Loose Part Monitoring System (LPMS) for improving diagnosis capability in nuclear power plants.