• The Journal of Engineering Geology
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• v.29 no.3
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• pp.279-288
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• 2019

The groundwater drawdown at each monitoring well near a radial collector well along Anseong Stream, Korea, was measured and compared with the calculated drawdown using the mirror well concept. The drawdown calculation is performed by treating the collector well as a large vertical well in a homogeneous isotropic aquifer. The measured drawdown at each monitoring well is slightly different from the calculated value due to anisotropy in the hydraulic conductivity and aquifer thickness. The difference between the measured and calculated values at Well OW-7 is large, reaching approximately 48 cm, because a horizontal well is not installed along this direction. Sensitivity analysis of the hydraulic conductivity and aquifer thickness indicates that the hydraulic conductivity is more sensitive to groundwater level changes. Groundwater level changes become a concern when a radial collector well with a large pumping rate capacity is installed, which highlights the need to thoroughly investigate the aquifer characteristics in the surrounding area.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.6
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• pp.77-83
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• 2020

The heat treatment facility is in a situation where the scope of application of the remote IOT system is expanding due to the harsh environment caused by high heat and long working hours among the root industries. In this heat treatment process environment, the IOT middleware is required to play a pivotal role in interpreting, managing and controlling data information of IoT devices (sensors, etc.). Until now, the system controlled by the heat treatment remotely was operated with the command of the operator's batch system without overall monitoring of the site situation. However, for the safety and precise control of the heat treatment facility, it is necessary to control various sensors and recognize the surrounding work environment. As a solution to this, the heat treatment safety support system presented in this paper proposes a support system that can detect the access of the work manpower to the heat treatment furnace through thermal image detection and operate safely when ordering work from a remote location. In addition, an OPEN CV-based deterioration analysis system using DNN deep learning network was constructed for faster and more accurate recognition than general fixed hot spot monitoring-based thermal image analysis. Through this, we would like to propose a system that can be used universally in the heat treatment environment and support the safety management specialized in the heat treatment industry.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.6
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• pp.559-575
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• 2021

Due to the increase in ground excavation work, the possibility of ground subsidence accidents is increasing. And it is very difficult to prevent these risk fundamentally through institutional reinforcement such as the special law for underground safety management. As for the various cases of urban ground excavation practice, the ground subsidence behavior characteristics which is predicted using various information before excavation showed a considerable difference that could not be ignored compared to the results real construction data. Changes in site conditions such as seasonal differences in design and construction period, changes in construction methods depending on the site conditions and long-term construction suspension due to various reasons could be considered as the main causes. As the countermeasures, the safety management system through various construction information is introduced, but there is still no suitable system which can predict the effect of excavation and risk assessment. In this study, a web-based system was developed in order to predict the degree of impact on the ground subsidence and surrounding structures in advance before ground excavation and evaluate the risk in the design and construction of urban ground excavation projects. A system was built using time series analysis technique that can predict the current and future behavior characteristics such as ground water level and settlement based on past field construction records with field monitoring data. It was presented as a geotechnical data visualization (GDV) technology for risk reduction and disaster management based on web-based system, Using this newly developed web-based assessment system, it is possible to predict ground excavation impact prediction and risk assessment.

• Korean Journal of Construction Engineering and Management
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• v.9 no.1
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• pp.176-186
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• 2008

The radio frequency identification (RFID) technology allows various forms of applications in many industries including construction. and in Korea, RFID has already been adopted for the use in daily labor control, logistics monitoring of ready-mix concrete, supply chain management of long-lead items, such as structural steel members and curtain walls. Even though RFID tags have varied reading performances depending on various factors including material of tracking target and surrounding environment, there is no information on how much the reading performance of an RFID tag can be achieved against a specific construction components or materials. Therefore, the objective of this research is to identify the actual reading performance of various RFID technologies and to derive a method to maximize the reading performance for the use in the supply chain management process of curtain wall components.

• Korean Journal of Microbiology
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• v.49 no.2
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• pp.150-155
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• 2013

We have conducted pyrosequencing for freshwater microbial community analyses. Fourteen sites along the Yeongsan river were selected for this study, and samples were collected monthly from May to July, 2012. Total 987,380 reads were obtained from 42 samples and used for taxonomic classification and OTU distribution analysis. Our results showed that high geographical and temporal variation in the phylum level bacterial composition, suggesting that microbial community is a very sensitive parameter affected by the surrounding environments including tributaries and land use nearby. In addition, we conducted an OTU-based Microbial Source Tracking to identify sources of fecal pollution in the same region. From this study Firmicutes was found to be the most influential taxa in this region. Here, we report that the use of pyrosequencing based microbial community analysis may give an additional information on freshwater quality monitoring, in addition to the currently used water quality parameters, such as BOD and pH.

• Journal of Environmental Health Sciences
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• v.40 no.1
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• pp.27-37
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• 2014

Objectives: On September 27, 2012, leakage of anhydrous hydrofluoric acid occurred in a chemical plant in the Gumi National Industrial Complex. Following the accident, local factory workers and residents complained of abnormal health conditions. In addition, visual discolorations were widely observed in crops and trees in surrounding areas. The main objectives of the present study were to identify the area that was affected by the spill using data obtained from plants, soil, and water samples after the accident. Methods: Fluoride concentrations were analyzed in pine tree needles, soil, nearby streams, ponds and reservoirs collected from an area within a radius of three kilometers from the plant where the leak occurred. Fluoride concentrations in the air at the time of leakage were then estimated from fluoride concentrations that were measured in the pine tree needles. A Kriged map was developed to describe the spatial distribution of hydrofluoric acid at the time of the leakage and was compared with the area designated as a Special Disaster Zone by the government. Results: The Special Disaster Zone did not include all the affected area that was estimated by the Kriged map. Analytical results of the environmental samples also supported this discrepancy. Conclusion: Using plants, atmospheric concentrations of fluoride at the time of the leakage could be estimated. For the area that was identified as affected, further public health risk assessment and environmental risk assessment should be considered. Also, in the absence of air monitoring at the time of leakage, studies employing plants may be conducted in order to better understand the spatial extent and severity of the contamination.

• Korean Journal of Environmental Agriculture
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• v.28 no.4
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• pp.340-346
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• 2009

Chromated copper arsenate (CCA) is a chemical wood preservative that has been intensively used to protect wood from decay during the last few decades. CCA is widely used to build structures such as decks, fences, playgrounds and boardwalks. However, structures constructed of CCA-treated wood have caused adverse environmental effects due to leaching of Cr, Cu and As into surrounding soils. This research was conducted to monitor the vertical and horizontal distribution of Cr, Cu and As in soils adjacent to CCA-treated wood structures in Korea. Two structures constructed with CCA-treated wood were selected at Hongcheon and Chuncheon in Gangwon Province, South Korea. Eleven soil profile samples were collected at depths of 0 to 80 cm at each site, while 12 surface soil samples were collected at distances of 0 to 200 cm from each structure. The soil chemical properties, soil particle size distribution and total metal concentrations were then determined. The results revealed that soils near CCA-treated wood structures were generally contaminated with Cr, Cu and As when compared to the background concentration of each metal. In addition, the concentrations of Cr, Cu and As in soils decreased as the vertical and horizontal distance from the structure increased. Further studies should be conducted to evaluate the mobility and distribution of these metals in the environment as well as to develop novel technologies for remediation of CCA contaminated soils.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2015.07a
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• pp.302-304
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• 2015

Waters that are under surveillance for traffic safety designated area due to increased risk of ship accidents are usually areas in the coastal waters specified by the government. However, there are still some controversies surrounding application of navigation rule in regards to these waters. Such law is especially difficult to apply to VTSO access sea route within Kwangyang bay area. Therefore, as a solution for the issues discussed in this research, the goal is to help establish a unified application method for navigation rule in relation to VTS areas, to improve marine traffic safety by separating and applying specific laws from marine safety law, and to provide a ground on which the VTSO can take a proactive and focused approach in performing monitoring duties.

• Journal of Conservation Science
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• v.19
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• pp.85-98
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• 2006

Rock property of the Seosan Maaesamjonbulsang is composed of biotite granite with medium grained texture. The triad Buddha is highly deteriorated by the joint, fracture, break-out, exfoliation, dew condensation of the surface and discoloration of the secondary pollutant. Host rock of the triad Buddha is divided dozens of rock blocks with various shape, and developed irregular discontinuity planes. Besides, the host rock is promoted biological pollution due to the surrounding crowded vegetation and high humidity environment. As the results of structural stability, it is confirmed that developed discontinuity system in the host rock is exposed instability sloping environment. Therefore, the host rock and surroundings are required maintenance, and required preservation by continuance monitoring for understand behavior of discontinuity system.

• The Journal of the Korea Contents Association
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• v.18 no.2
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• pp.378-387
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• 2018

With the advent of the fourth industrial revolution in recent years, the field of health care services is getting attention again. Accordingly, personalized medical systems through smart products are emerging in various forms. With the use of wearable tech and sensor system, health management and monitoring can be done anytime, anywhere without help of others. However, healthcare services for pregnant women are very scarce. Due to the low fertility rate the number of obstetrics and gynecology is decreasing and as a result, environment surrounding the uncomfortable pregnant women is getting worse. Pregnant women are unable to take a comfortable sleeping posture due to pregnancy. Various environmental factors such as noise, temperature and humidity decrease the quality of sleeping of pregnant women and hinder happy preaching. The purpose of this study is to develop a UI design that can manage sleeping by providing good sleeping posture information and improved sleeping environment for the health of pregnant women. We expect to apply the sensor technology of the 4th industrial age to maximize the sleep quality and quality of life of expectant mothers.