• Fire Science and Engineering
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• v.20 no.4 s.64
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• pp.26-32
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• 2006

Nowadays in Korea, KS F 2271 has been using for the test of fire safety performance of sandwich panels. Smoke toxicity test is the test for the toxicity evaluation of smoke and hazardous gas, caused by combustion of building materials and finishing materials. Smoke toxicity can be evaluated by the mean incapacitation time of mice; however this method is not a quantitative way. This test result can be influenced by the health status of mice and test condition. Specific optical density can be quantitatively measured by ISO 5659-2 single chamber method and toxic gases can be quantitatively measured by FTIR analysis. In this study, specific optical density of sandwich panel insulations, which are widely used in Korea, were tested using the ISO 5659-2 single chamber test method and compared with each test. Also, in the second test of three tests for each specimen, FTIR analysis was performed and quantitative test results(HCl, $NO_2$, etc) were compared with each test result.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2009.04a
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• pp.255-263
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• 2009

A indoor hydrant proportioner that is installed as fire extinction equipment when a fire breaks out in a building plays a vital role for a fire extinction at an early stage. The indoor waterproof hydrant proportioner installed currently can function in case of fire as fire extinction equipment only when it can maintain proper waterproof pressure meeting the standards stipulated in NFSC. The results of the survey on the waterproof pressure of the indoor hydrant proportioner installed in most buildings showed that the waterproof pressure installed inside the buildings was higher than the agreed level suggested by NFSC, which is very desirable state and is regarded as the results of fire facilities being maintained and managed by regular fire inspections. It is thought that the safety management of fire extinction facilities should be kept up both regularly and steadily through TAB.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.4
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• pp.95-105
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• 2021

Road surface damage detection is essential for a comfortable driving environment and the prevention of safety accidents. Road management institutes are using automated technology-based inspection equipment and systems. As one of these automation technologies, a sensor to detect road surface damage plays an important role. For this purpose, several studies on sensors using deep learning have been conducted in recent years. Road images and label images are needed to develop such deep learning algorithms. On the other hand, considerable time and labor will be needed to secure label images. In this paper, the adversarial learning method, one of the semi-supervised learning techniques, was proposed to solve this problem. For its implementation, a lightweight deep neural network model was trained using 5,327 road images and 1,327 label images. After experimenting with 400 road images, a model with a mean intersection over a union of 80.54% and an F1 score of 77.85% was developed. Through this, a technology that can improve recognition performance by adding only road images was developed to learning without label images and is expected to be used as a technology for road surface management in the future.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.2
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• pp.1-7
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• 2023

Durability was evaluated by performing a full-scale vertical load fatigue test and a wheel load performance test on the HRS, which reduces the replacement time of the existing expansion joint and improves serviceability to allow partial replacement by lane. As a result of the vertical load fatigue test, the maximum stress of the rail-type expansion joint is 170 MPa, which is about 47.8% of the yield strength of the HRS expansion joint rail 355 MPa. The vertical load fatigue test of the HRS expansion joint with improved serviceability set the size and load of the load plate according to the road bridge design standards, did not show any fracture behavior in the vertical load fatigue test and the wheel load performance test 2 million times, and its durability and safety were verified.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6D
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• pp.985-993
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• 2006

The use of prefabricated concrete piles have been gradually increased in many construction sites. One of main works for building a concrete pile foundation is to crush a part of pile head which is compressed with more than $800kg/cm^2$. A pile cutting work is usually performed by a crusher and three to four skilled workers. Recent reports on the pile cutting work reveal that a lot of cracks which significantly reduce the strength of the pile and are frequently made during pile cutting operations and it is very repetitive and labor intensive work. To improve productivity, safety, and quality of the conventional concrete pile cutting work, the research on developing an automated concrete pile cutter has been performed. In this paper, sensing methods for detecting a pile cutting line are suggested with operation process algorithms. The suggested methods are very important to develop the automated pile cutter. A pilot-type of the automated pile cutter that adopt one of the suggested sensing methods, is developed and tested in a construction site.

• Korean Journal of Construction Engineering and Management
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• v.8 no.1 s.35
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• pp.57-65
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• 2007

Rebar work is a labor intensive operation, and with labor shortage and high-wage era, the cost is rising, so re-bar manufacturing system in plant is adapted. However there remains a lot of problems. Although manufacturing system in plant, which greatly effects the building's safety, endurance, and construction time, is an important phase in construction, it holds serious problem of quality and productivity deterioration due to its characteristic of intensive-labor and maintaining of old work methods resulting in poor management, and costs increase. Therefor in this study to investigate current situation and problems of rebar work in plant and to find methods of betterment, a survey was conducted to factory engineers in 18 companies.

• The Journal of Engineering Geology
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• v.28 no.3
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• pp.455-463
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• 2018

This study developed a method to quantitatively measure the size of cracks in concrete using X-ray CT images. We prepared samples with a diameter of 50 mm and a length of 100 mm by coring cracked concrete block that was obtained by chipping. We used a micro-focus X-ray CT, then applied the 3DMA method (3 Dimensional Medial axis Analysis) to the 3D CT images to find effective parameters for damage assessment. Finally, we quantitatively assessed the damage based on sample locations, using the damage assessment parameter. Results clearly show that the area near the chipping surface was damaged to a depth of 3 cm. Furthermore, X-ray methods can be used to evaluate the porosity index, burn number, and medial axis, which are used to estimate the damage to the area near the chipping surface.

• Journal of the Earthquake Engineering Society of Korea
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• v.15 no.4
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• pp.23-31
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• 2011

To investigate the performance of apartment buildings which were built in the 1990s and which have RC bearing wall systems with coupling beams, construction drawings of 13 buildings were collected and analyzed. To evaluate the seismic performance, FEMA 356 and FEMA 440 were selected as guidelines. For the demand curve, the seismic design spectrum in KBC 2009 is used. For each building, the performance points for life safety and the collapse prevention state are calculated. It was found that 9 out of 13 buildings (about 70%) showed damage more severe than the collapse prevention level at the performance point and more damage could be seen at the coupling beams than the walls. However, the story drift limit of FEMA 356 was satisfied for all buildings. Through the analysis of performance points, it was shown that the spectral acceleration has an inverse relationship with the natural period.

• Korean Journal of Construction Engineering and Management
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• v.14 no.4
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• pp.73-83
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• 2013

Recently, not only around Korea but also other countries shows a pattern of arising high-rise building construction project which was delayed or aborted during global economic crises and recession. Although the market starts to stretch, It is getting competitive to win a contract in high-rise construction project between contractors due to lack of competitive advantage especially to Korea contractors. To get that, Korean contractors needs lifting equipment plan. But currently, they depend on the empirical methods and that cause schedule delay, not controlled cost management problem. Therefore, this research is to improve the accuracy of Lifting plan by analyzing the current issues of Lifting plan system and deducing the types of failures with planning factors, as well as analyzing the impact on schedule and cost control and safety management by each failure mode. Also, by analyzing detail risk factors per Lifting Equipment with FMEA, to infer the critical risk factor on high-rise construction project.

• The Journal of Fisheries Business Administration
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• v.49 no.3
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• pp.67-83
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• 2018

This study is aimed at finding policy directions for Korean fisheries and fishing villages by using Delphi method for fisheries experts. Fisheries experts have highly evaluated the achievements of fostering aquaculture industry, seafood export support measures, and natural disasters relief and recovery arrangements among the policies promoted as so far. And it was recognized that policies such as fishery resources management, creation and recovery of fishery resources, improvement hygiene and seafood safety, and provision young fishermen with training and capacity building will be important. Future megatrends, for example changes in food consumption pattern, climate change, and demographic structure changes are expected to have a significant impact on fisheries and fishing villages. The Delphi survey indicates that the most important policy objective is to secure a stable fisheries production. In other words, fisheries policy in the future should be aimed at suppling sustainable seafood for popular consumption. Finding strategies and action plans that can achieve this goal will be an important policy issue. In conclusion, it is necessary that a number of fundamental researches carry out in Korea, which can lead to finding out a multifunctionality of fisheries and fishing village. In addition, it is important to expand the scope of fisheries policy, which can consider not only the fisheries producers but also seafood consumer's and young fishermen perspectives. Furthermore, it recommends that fishery policy needs to include fishery related industry as well as application of 4th industrial revolution technology to fishery.