• Proceedings of the IEEK Conference
• /
• 2001.06a
• /
• pp.53-56
• /
• 2001

This paper has been developed a millimeter-wave radar to prevent car collision. This system needs to progress the problem as follows; (1) Increase of traffic accidents causing damage and injuries due to the increased number of motor vehicles and long distance driving, (2) Need for a device to help drivers who are in trouble due to bad weather conditions. (3) Need for a millimeter-wave radar as obstacles which need to be detected are small. This system is composited with some major technologies, Narrow beams to recognize obstacles or other objects, One-side circuit technology to prevent interference between electric waves, and Parts designed for radar products which are able to transmit millimeter - waves. The system has a various a application Field, Car distance auto-control system, prevent bump collision due to unexpected stoppage of the front car or careless driving, obstacle warning system, Car following system, and industrial and military purposes system. We have a looking forward to propose to develop field tests under various road conditions and hybrid car sensor by combining with other sensors

• Journal of the Korean Society of Safety
• /
• v.31 no.1
• /
• pp.105-110
• /
• 2016

Mountainous disasters such as landslides and debris flow are difficult to forecast. Debris flow in particular often flows along the valley until it reaches the road or residential area, causing casualties and huge damages. In this study, the researchers selected Seoraksan National Park area located at Inje County (Inje-gun), Gangwon Province-where many mountainous disasters occur due to localized torrential downpours-for the damage reduction and cause analysis of the area experiencing frequent mountainous disasters every year. Then, the researchers conducted the field study and constructed geospatial information data by GIS method to analyze the characteristics of the disaster-occurring area. Also, to extract more precise geographic parameters, the researchers scanned debris flow triggering area through terrestrial LiDAR and constructed 3D geographical data. LiDAR geographical data was then compared with the existing numerical map to evaluate its precision and made the comparative analysis with the geographic data before and after the disaster occurrence. In the future, it will be utilized as basic data for risk analysis of mountainous disaster or disaster reduction measures through a fine-grid topographical map.

• Journal of Biosystems Engineering
• /
• v.42 no.1
• /
• pp.12-22
• /
• 2017

Purpose: This aim of this study was to develop a pick-up type pulse crop harvester for harvesting cut and dried pulse crop. Methods: The pick-up type pulse crop harvester was designed and constructed. Its specifications and operating performance were investigated. Results: Compared with conventional bean harvesters, the pick-up type pulse crop harvester adopted seven rows of chains with tines to pick-up the cut and dried pulse crop on a flat or ridged field, two transverse threshing drums with steel wire teeth to reduce the threshing speed, and a tilt plate and plastic bucket elevator for conveying clean grain to reduce damage. The threshing speed and the oscillating frequency of the separating and cleaning parts according to crop type and condition could be varied easily to efficiently use engine power and to improve harvesting performance. The harvester showed forward speed ranges of 0 ~ 1.5 m/s during harvesting operation, and 0 ~ 2.5 m/s during road travelling. The pick-up width of the harvester was about 1 m. Conclusions: The pick-up type self-propelled 51.5 kW harvester was designed and constructed to harvest cut and dried pulse crop. The effective field capacity of the harvester was predicted as above 40 a/h.

• International Journal of Highway Engineering
• /
• v.20 no.4
• /
• pp.27-34
• /
• 2018

PURPOSES : The objective of this study is to evaluate the physical properties of recycled asphalt mixtures reinforced with glass fiber. METHODS : Firstly, mixing design was conducted on recycled asphalt mixture for use of 50% recycled aggregate. Various laboratory tests were performed on four types of recycled asphalt mixtures with different glass fiber content to evaluate the physical properties. The laboratory tests include indirect tensile strength test, dynamic modulus test, Hamburg wheel tracking test and tensile-strength ratio to evaluate cracks, rutting and moisture resistance of mixtures. RESULTS : The indirect tensile strength of fiber reinforced glass increased about 139.4%. As a result of comparing the master curves obtained by the dynamic modulus test, the elasticity was low in the low temperature region and high in the high temperature region when the glass fiber was reinforced. The glass fiber contents of PEGS 0.3%, Micro PPGF 0.1% and Macro PPGF 0.3% showed the highest moisture resistance and rutting resistance. CONCLUSIONS : The test results show that use of glass fiber reinforcement can increase the resistance to cracking, rutting, and moisture damage of asphalt mixtures. It is also necessary to validate the long-term performance of recycled asphalt mixtures with glass fiber using full scale pavement testing and field trial construction.

• International Journal of Highway Engineering
• /
• v.17 no.5
• /
• pp.83-92
• /
• 2015

PURPOSES : Traffic accidents and damage due to speeding should be recognized as a problem which harms society and the economy as well as the parties to the accidents. It is time to seek more detailed and concrete customized alternatives than the existing policies for the prevention of traffic accidents. METHODS: In this study, we identified the characteristics driver behavior and psychological factors that lead to speeding, and a study was carried out to verify the causality models developed from the factors we identified. RESULTS : Driving behavior variables have a significant effect on speeding behaviors in order of Lapse, Violation, and Mistake. And the violation which is defined as intentional violation showed the result which supports the research hypothesis as it has the significant effect on speeding intention and behaviors. CONCLUSIONS: The result of this study can be utilized to develop educational problems concerning speeding and previous response with the main objective of eliminating speeding driver behavior.

• International Journal of Highway Engineering
• /
• v.15 no.4
• /
• pp.117-125
• /
• 2013

PURPOSES : The purpose of this study is to evaluate of field application and laboratory performance of warm-mix asphalt (WMA) according to the dosage rate of organic-based WMA additive. METHODS: Three asphalt mixtures, i.e., hot mix asphalt (HMA), WMA with the dosage rate of 1.5%, WMA with the dosage rate of 1.0%, were sampled from the asphalt plant when the field trial project were constructed. With these mixtures, the laboratory testings were performed to evaluate the linear viscoelastic characteristics and the resistance to moisture, rutting and fatigue damage. RESULTS : From the laboratory test results, it was found that the WMA with the reduced dosage rate of additive would be comparable to HMA and WMA with the original dosage rate in terms of the dynamic modulus, tensile strength ratio, rutting resistance. However, the fatigue reisistance of WMA with the reduced dosage rate was slightly worse but it should be noted that the fatigue performance is necessarily predicted by combining the material properties and pavement structure. CONCLUSIONS: Through the field construction and laboratory testings, the dosage rate of organic-based WMA additive could be reduced from 1.5% to 1.0% without the significant decrease of compactability and laboratory performance. The long-term performance of the constructed pavement will be periodically monitored to support the findings from this study.

• Proceedings of the KSR Conference
• /
• 2009.05a
• /
• pp.1509-1513
• /
• 2009

The research of applying reinforced retaining wall due to support the land pressure that given from train's load has been accomplished actively in domestic area. After the retaining wall has been installed, the collapse or partial destruction that generated by effect of train's vibration and repetitive load of train may be induced. Accordingly in the period of using this, the sufficient durability should be guaranteed and years of durability are one hundred and as these are longer than road structure's, the technique that introduced to wall and monitor the long-term strain is necessary. In this paper, the optical fibre is induced vertically to the reinforced retaining wall and after the subsistence of optical fibre is confirmed, the early strain that applied to optical fibre after insertion is monitored. Before and after the concrete placing, damage feasibility of optical fibre is measured by using OTDR(Optical Time Domain Reflectometer) and after concrete is cultivated, the early strain induced to optical fibre is measured by application of BOCDA (Brillouin Correlation Domain Analysis) system.

• Smart Structures and Systems
• /
• v.22 no.4
• /
• pp.383-397
• /
• 2018

Traditional base isolation systems focus on isolating the seismic response of a structure in the horizontal direction. However, in regions where the vertical earthquake excitation is significant (such as near-fault region), a traditional base-isolated building exhibits a significant vertical vibration. To eliminate this shortcoming, a rocking-isolated system named Telescopic Column (TC) is proposed in this paper. Detailed rocking and isolation mechanism of the TC system is presented. The seismic performance of the TC is compared with the traditional elastomeric bearing (EB) and friction pendulum (FP) base-isolated systems. A 4-storey reinforced concrete moment-resisting frame (RC-MRF) is selected as the reference superstructure. The seismic response of the reference superstructure in terms of column axial forces, base shears, floor accelerations, inter-storey drift ratios (IDR) and collapse margin ratios (CMRs) are evaluated using OpenSees. The results of the nonlinear dynamic analysis subjected to multi-directional earthquake excitations show that the superstructure equipped with the newly proposed TC is more resilient and exhibits a superior response with higher margin of safety against collapse when compared with the same superstructure with the traditional base-isolation (BI) system.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2017.10a
• /
• pp.341-342
• /
• 2017

Control and development systems such as air traffic control systems, road traffic systems, and Korea Hydro &Nuclear Power are the infrastructure facilities of the country, and if the malicious hacking attacks proceed, the damage is beyond imagination. In fact, Korea Hydro & Nuclear Power has been subjected to a hacking attack, causing internal information to leak and causing social problems. In this study, we analyze the environment of the development control system and analyze the status of the convergence security research, which is a recent issue, and propose a strategy system for stabilizing various power generation control systems and propose countermeasures. We propose a method to normalize and integrate data types from various physical security systems (facilities), IT security systems, access control systems, to control the whole system through convergence authentication, and to detect risks through fusion control.

• International Journal of Highway Engineering
• /
• v.16 no.1
• /
• pp.31-39
• /
• 2014

PURPOSES : Surface treatment material for pavement preventive maintenance should be inspected field applicability. This study(Part II) aimed to checkup coating characteristics and performance analysis using lab and field tests. The hydrophobic - low viscosity filling material for pavement preventive maintenance is presented in Part I, which is a series of companion study. METHODS : Relative comparison between general asphalt mixtures and surface treatment asphalt mixtures are analyzed and measured for the field application such as indirect tensile strength ratio(TSR), abrasion resistance, crack propagation resistance, temperature resistance, coating thickness, permeability resistance and skid resistance in terms of british pendulum number(BPN). RESULTS : It is found that TSR, crack propagation resistance and permeability resistance is increased as against uncoated asphalt specimen. Abrasion resistance and temperature resistance is secured from the initial coating thickness point of view, which is about 0.2~0.3mm. Skid resistance on the surface treatment pavement is satisfied with the BPN criteria of national highway because of exposed aggregate and crack sill induced pavement deterioration and damage cracks. CONCLUSIONS : The hydrophobic - low viscosity surface treatment material for pavement preventive maintenance is validated on field applicability evaluation based on quantitative analysis of coating thickness and performance analysis using lab and field tests.