• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.760-763
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• 2004

This work presents OLP system made independently in HSD for sub-assembly welding robot system set already and assembly welding robot system developed lately on the low speed diesel engines. This paper focuses on the DB module and the job creation based upon it. Also, It contains the welding history DB that saves the information of jobs executed after welding.

• Journal of Environmental Health Sciences
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• v.24 no.2
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• pp.145-150
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• 1998

This study was carried out to investigate the loss amount of collection at the different of precipitatation time, high voltage and gas speed. This work has focused on the dependence of the collection efficiency in the collector zone with gas speed and high voltage. This advanced Model is developed by research of the different parameter as the conventionnal modem of study. In order to investigate collection efficiency of electrostatic precipitator, the loss amount of knocking was measured with Monitek-Treubung and the particle size was analyzed by He-Ne laser diffraction spectroscopy.

• Journal of Ship and Ocean Technology
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• v.9 no.2
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• pp.29-36
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• 2005

A hull form of Baltic ice class IA Aframax tanker has been developed taking into consideration of powering performance in brash ice channels based on IA class rules. Speed performance of the ship hull form in normal seagoing has been validated through model tests in a towing tank. The hull form design developed in this work has demonstrated good speed performance in normal seagoing although the ship design is entitled to ice class IA.

• Proceedings of the Korea Society for Simulation Conference
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• 1999.04a
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• pp.88-92
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• 1999

As a part of work to simulate electromagnetic environments for Hardware-In-the-Loop(HIL) simulation, the dynamic trajectory is modeled by the Way-points method and the Event-driven method for the aerial and the naval targets. The simulated results show that the Way-points method and the Event-driven method are appropriate to simulate a low speed and a high speed target respectively.

• Journal of Korean Society of Transportation
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• v.31 no.1
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• pp.37-46
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• 2013

Lane closure in freeway work zone due to maintenance and repair of freeway facilities results in abrupt change of traffic flow. Sudden change of traffic flow results strong interactions among vehicles, and reduces capacity compared to the ordinary traffic condition. Such capacity reduction is likely to cause congestion, traffic queues, and economic loss cost. This study aims to determine the base capacity for a short-term freeway work zone that can be used to establish a work zone schedule in advance without any traffic impact. First, the research collected detector data and schedule data of road works on all freeways in Korea. Second, the research determined 23 study sites finding the capacity values of work zone after matching two kinds of data. All study sites had varying characteristics regarding traffic flow being adjacent to work zone during road works. The capacity values were reviewed in terms of lane closure configuration, the types of work, and design speed. Finally, research proposed capacity values for a short-term freeway work zone with the design speeds of 100 kph, 120 kph and 1,700 pcphpl, 1,750 pcphpl, respectively.

• Journal of Korean Society of Transportation
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• v.31 no.5
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• pp.3-15
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• 2013

The purpose of this study is to propose a methodology for operating variable speed limit (VSL) strategies in freeway work zones. A notable feature in this study is to incorporate a multi-criteria decision making process into deriving better VSL strategies. Decision criteria in this study include operational efficiency, safety, and environmental impacts. Travel speed, acceleration noise, and CO2 were used as performance measures for evaluating VSL strategies. A multi-criteria value function was developed through an analytical hierarchical process (AHP) for representing expert's knowledge. Then, a variety of VSL operations scenarios were investigated utilizing a microscopic traffic simulation suite, VISSIM. The proposed methodology would be useful in supporting more efficient, safer, and more environment-friendly traffic operations and control in freeway work zones.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.1
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• pp.34-44
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• 2021

In order to collect basic information of response behavior of red seabream (Pagrus major) during pilling, works for constructing wind power station in Byeonsan Peninsular, Korea were investigated. Four cultured red seabream CRB1 to CRB4 [total length (TL): 27.1 ± 1.0 cm; body weight: 359 ± 30 g] were tagged with an acoustic tag and used in experiment. CRB1 and CRB2 to CBR4 were released on the sea surface at same time around the constructing site of the wind power plant on September 22, 2017 and July 18, 2018, respectively. The tracking of the CRB1 to CRB2 and CRB3 to CRB4 were conducted for two hours, approximately, using VR100 receiver including a directional hydrophone and VR2W receivers array consisted of 19 presence/absence receivers (VR2W receivers), respectively. The underwater noise level before (no pile driving works) and during pile driving works was measured 116.0-118.0 dB (re 1��Pa) and a maximum of 160 dB (re 1��Pa), respectively. CRB1 moved about 6.0 km with average swimming speed of 80.2 ± 20.5 cm/s for 2.1 hours without pile driving work. The average water depth of the sea bed on the route of CRB1 was 9.1 ± 0.4 m. CRB2 moved about 7.3 km with the average swimming speed of 96.8 ± 27.1 cm/s for 2.1 hours with pile driving work. The water depth of the sea bed on the route of CRB2 was 11.9 ± 0.6 m. At results of the Rayleigh's z-test two fishes CRB1 and CRB2 showed significant directionality in the movement (p < 0.01). Movement mean angles of CRB1 and CRB2 were 92.7 and 251.8°, respectively. CRB2, CRB3 and CRB4 exhibited the escaping behavioral response from the noise of source during the pile driving work. The swimming speed of the CRB2 exposed on the heavy underwater noise stimuli due to the pile driving work was 1.21 times faster than that of the CRB1 exposed on the ambient underwater noise in the study site.

• Journal of Korean Institute of Industrial Engineers
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• v.16 no.1
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• pp.67-81
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• 1990

Effectiveness of physical exercise in reducing work-related musculoskeletal stress was investigated. This was compared to the stress alleviation accomplished by using ergonomically designed work station. Tasks chosen for the study were data entry and file maintenance on the video display terminal (VDT). Three different measures, namely root-mean-square (RMS) values of electromyogram (EMG), subjective rating and task performance were used for the evaluation. Electromyograms were recorded from the neck, the left and right trapezius muscles in the shoulder region, and L2/L3 region of the back. Subjects rated discomfort levels for the same parts of their body. Task performance was measured by recording typing speed and errors. Each of the five subjects was tested for two days (8 hours/day) in two different work stations. These were the ergonomically designed adjustable work station and the fixed work station of traditional design with no adjustable features. Assigned physical exercises were performed for four minutes, every two hours during the breaks, by the subjects while working in the fixed work station. It was concluded that the physical exercise could be helpful in reducing musculoskeletal stress as effectively as the ergonomic design of the VDT work station.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.952-959
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• 2022

Active construction work zones will result in longer travel time and/or longer travel distances for road users because of reduced speed limits and/or detours. This results in increased fuel consumption and increased emissions of harmful gases such as Carbon Monoxide (CO), Nitrogen Oxides (NOx), and Sulfur Oxides (SOx), which causes discomfort to the environment and road users around the work zone. The impact of such emissions should be considered while designing work zones or determining the number of days the roadway will be allowed to be closed partially or fully. This study develops a methodology to compute additional road user costs associated with such work zones. To achieve this goal, a) an extensive literature review is conducted, b) a framework to compute emission cost is developed, c) emission rates are computed for all counties (95) of the state of Tennessee, and d) a case study is conducted to demonstrate the use of the framework to estimate the additional impact of emission because of the work zone. For the case study conducted, the emission cost was computed to be $10,653.60 for the duration of the project. State DOTs can account for such road user costs while selecting contractors using A+B bidding. Accounting for such impact of emission will also indicate the agency's willingness to consider sustainability as a part of the business practices.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.237-238
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• 2023

When primer is applied manually, adhesion performance decreases due to a decrease in primer penetration performance on the surface, and construction period delay may occur due to a long time due to a decrease in work efficiency when a large area is worked using a conventional roller. In addition, in the case of the roller method, precision work in corners and narrow spaces is not possible, so it is urgent to come up with measures to ensure uniform quality. In addition, secondary work occurs to remove fine powder from the surface before primer application, resulting in construction period delay due to the rise of the working stage. Therefore, in this study, equipment was used instead of manual work for primer work, and as a result, penetration performance and adhesion performance were improved about twice. From these results, it was confirmed that favorable results such as improving work speed, securing high quality, improving the working environment, and resolving the shortage of functional workers can be obtained.