• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1047-1048
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• 2013

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.153-162
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• 2005

The structural specification of the rockfall prevention fence installed on the road section is computed according to the hypothetic rockfall energy, and the absorbable energy of the rockfall prevention fence is defined as the sum of the absorption energies of the wire rope, one of the components, the steel support and the wire netting. But the results of the field tests confirmed that the absorption energy of the rockfall prevention fence is not the sum of the energies sustainable by the components, but it is affected by the absorbable energy of part of the components. This shows there are problems with the method of computing the absorption energy of the rockfall prevention fence of the road. So in this paper, as a way of solving the problems, the effects of improving the performance through positional changes of the existing components and the effects of improving the performance through structural changes by expanded metal are checked through tests, and a plan was proposed to solve the problems with the standards of installing the conventional rockfall prevention fence.

• Journal of the Society of Disaster Information
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• v.18 no.1
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• pp.154-162
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• 2022

Purpose: The government intends to come up with measures to revitalize safety management at construction sites to shift safety management at construction sites from human capabilities to system-oriented management systems using advanced technologies AIoT and Mobile technologies. Method: The construction site safety management monitoring system using AIoT and Mobile technology conducted an experiment on the effectiveness of the construction site by applying three algorithms: virtual fence, fire monitoring, and recognition of not wearing a safety helmet. Result: The number of workers in the experiment was 215 and 7.61 virtual fence intrusion was 3.5% compared to the number of subjects and 0.16 fire detection were 0.07% compared to the subjects, and the average monthly rate of not wearing a safety helmet was 8.79, 4.05% compared to the subjects. Conclusion: It was found that the construction site safety management monitoring system using AIoT and Mobile technology has a valid effect on the construction site.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.6
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• pp.731-736
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• 2021

Oil fences effectively prevent the spread of oil spilled in the sea, thereby reducing the damage to the marine environment. However, the fence is damaged by oil and structures at the accident site and is discarded. When incinerated disposal method for discarded fences, fine dust, and harmful materials are generated. Moreover, as a part of the damaged fence is dumped into the sea, it may cause secondary environmental pollution, such as microplastics. Therefore, in this study, durability was measured using the most common solid foam type oil fences. As a result, the reduction rate of after five days of contact was 13 % in seawater and 3 % in oil, affected by temperature changes. Thus, the durability of the fence should be improved because it is exposed to seawater and oil and affected by wind, light, and waves depending on the weather conditions. Therefore, we suggest a method to improve the oil fence inspection to strengthen the durability of the fence's fabric part.

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.107-107
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• 2017

• Journal of the Korean Society of Marine Environment & Safety
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• v.17 no.1
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• pp.29-37
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• 2011

PIV measurements of the velocity field, pressure field, vorticity, and turbulent intensity in the rear of curved section of an oil fence with current speed showed that the flow directions in the rear of flow boundary area were similar to those in the front of it. As the current speed increased, the patterns of pressure distribution were changed, and the turbulent flow became more irregular. CFD simulations under the same conditions as the PIV tests showed that the flow patterns of the wake were similar to those by PIV tests in speed of 0.3 m/s and less, but were distinctively deviated from those in 0.4 m/s due to the flexibility of the oil fence, which was not properly taken care of in CFD modeling.

• Structural Engineering and Mechanics
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• v.12 no.5
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• pp.541-558
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• 2001

The design specifications of guard fences in Japan were reexamined and the revised specifications were implemented from April 1999. Because of the huge consumption in time and cost to test the performances of full-scale guard fences in the field, some assumptions are adopted while modifying the design specifications, and numerical analyses are necessary to confirm the impact performance and safety level of new types of steel highway guard fences. In this study, the finite element models are developed for the heavy trucks and steel highway guard fences to reenact their behaviors, and the solution approach is carried out using nonlinear dynamic analysis software of structures in three dimensions (LS-DYNA). The numerical simulation results are compared with the full-scale on-site testing results to verify the proposed analysis procedure. The collision process is simulated and it is also made possible to visualize the movement of the truck and the performances of guard fences. In addition, the energy shift of the truck kinetic energy to the truck and guard fence Internal energy, and the energy absorption of each guard fence component are studied for the development of a new design methodology of steel highway guard fences based on the energy absorption capacity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.755-761
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• 2015

Temporary fencing is a mandatory installation in construction sites because of environmental regulations and pedestrian safety. Contractors are responsible for the structural integrity of frames. The fence frame composed of a ledger and post is very weak in the out-of-plane direction, which is normally reinforced by diagonal bracing with a sub post. In this study, the location of lateral bracing for the main post was investigated analytically. Three types of frame were suggested and their performance was compared in terms of the maximum moment and deflection. A construction site may be located at city centers or crowed areas, and a contingent accident should be considered. The EOD type was found to be most efficient among the three frames suggested.

• Korean Journal of Construction Engineering and Management
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• v.1 no.3 s.3
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• pp.108-115
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• 2000

The average height of buildings in most cities is increasing in an effort to more effectively use land. In addition, as construction technology develops, rapid construction methods have been pursued. However, while there have been great strides in construction technology, the development of a temporary structure that can support the high-rise building under construction and the rapid construction methods has been relatively limited. If the temporary structure is not built on an outer wall of a building being constructed, a worker may be injured or killed in a fall and building materials such as blocks and other objects may fall to the ground, causing the build-up of trash around the building and possible injuries to persons in proximity to the building. This paper proposes a Self Climbing Safety Fence for construction building(SCfence). SCfence was developed to solve the above problems, a tent has been setup to cover the outer wall of the building, or a falling preventing net has been pitched in a direction perpendicular to the outer wall of the building. A case study was performed to verify the validity of SCfence through comparing the safety and cost experience between SCfence and the existing method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.9
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• pp.2145-2152
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• 2015

The existing CCTV has limitation such as problem on usage of the off-line type of recorded image for specific investigation, and requirement on interactive operator intervention for real-time surveillance. Therefore, it is required to develop the intelligent CCTV equipped with various functionalities in order to overcome drawbacks mentioned above. In this paper, implementation methods of image-based virtual fence were proposed by using the spline curves with supplied control for setup of surveillance area. In addition, pre-alarm region within the predefined distance was established with tangent and normal lines extracted from control points. The image-based virtual fence can be used for remote detection of intrusion and provision of real-time intrusion alarm, and can be expected to use in safety-related application areas including security and crime prevention.