• Korean Journal of Remote Sensing
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• v.27 no.1
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• pp.25-31
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• 2011

Precise control of antenna position is very critical in ArcSAR system which uses an arc-rail as a platform for the antenna movement instead of linear rail. In order to minimize the antenna positional error, we improved the motion driving system and applied a newly developed motion control S/W which utilizes the real time antenna position information from magnetic linear scale and encoder. The experimental results showed that the rotational RMS error was reduced to $0.0062^{\circ}$ from $0.0432^{\circ}$. In terms of antenna positional RMS error for the arm length of 3m, it was reduced to 0.324mm from 2.262mm. It is expected that the ArcSAR system can be used to monitor the sub-millimetric displacement of terrain and structural targets.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.649-652
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• 2005

The camera cellular phone has a large portion of cellular phone market in recent year. The variety of a customer demand makes a fast model change and the spatial resolution is changed from VGA to multi-mega pixel. The 1.3 mega pixel (MP) camera cellular phone was first released into the Korean market in October 2003. The major cellular phone companies released a 2MP camera cellular phone that supports zoom function and a 2MP camera cellular phone is settled down with the Korea cellular phone market. It makes a keen competition in price and demands automation for phone camera module. There is an increasing requirement for the automatic assembly to correspond to a fast model change. The hard automation techniques that rely on dedicated manufacturing system are too inflexible to meet this requirement. Therefore in this study, this system is designed with the flexibility concept in order to cope with phone camera module change. The system has a same platform that has X-Y-Z motion or X-Z motion with ${\mu}m$order accuracy. It has a special gripper according to the type of a component to be put together. If the camera model changes, the gripper may be updated to fit for the camera module. The controller of this system acquires the data sets that have the information about the assembly part by the tray. This information is obtained ahead of an inspection step. The controller excludes an inferior part to be assembled by using this information to diminish the inferior goods. The assembly jig used in this system has a function of self adjustment that reduces the tact time and also diminish the inferior goods. Finally, the intelligent assembly system for phone camera module will be designed to get a flexibility to meet model change and a high productivity with a high reliability.

• KEPCO Journal on Electric Power and Energy
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• v.6 no.2
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• pp.129-135
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• 2020

The standardization of e-IoT (energy Internet of Things) communication and service, which is the energy field of energy, is to define the standard model and to demonstrate the practical model in order to take the lead and occupy the market where new market is created with the latest technology. In particular, detailed technical specifications are defined for developing a framework for IoT technology, the foundation technology of the 4th Industrial Revolution, securing interoperability through standardization, and operating a standard platform. In this paper, we propose a method for e-IoT standard protocol lightening and test certification procedure. The proposed method provides a product implementation method that can solve the problem of low power issue of e-IoT product in the future.

• Journal of The Geomorphological Association of Korea
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• v.23 no.1
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• pp.117-128
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• 2016

High resolution aerial photographs and digital elevation models for Bangpo beach using UAV were generated in this study to analyze the thematic and geometric characteristics of coastal features. Based on 728 aerial images acquired on September 10, 2016 by the UAV, a image mosaic at 2.2 cm spatial resolution and a digital elevation model at 4.4 cm spatial resolution were developed. This study found out that Bangpo beach consisted of intertidal zone and supratidal zone. The intertidal zone can be subdivided into lower part and upper part with distinctive geomorphological characteristics. While the lower part included sand bars and ripple marks along the coastline, the cusps and sand dunes were the major coastal features of the upper part. Part of the intertidal zone was occupied by shore platform with average slope of 0.9 degree containing various sizes of gravels. The supratidal zone slanted toward ocean with berms on the surface with an interval of 15 m. These coastal features indicated the flow intensity towards to the land and tidal effect. It validated that the UAV application in coastal research was very effective analyzing to examine coastal processes.

• Journal of Appropriate Technology
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• v.6 no.2
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• pp.211-218
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• 2020

Since World Health Organization (WHO) declared Pandemic about COVID-19 at 11 March, 2020, 214 countries now have more than 5.8 million confirmed cases and 360 thousand deaths (29 March 2020). The pandemic of COVID-19 caused lockdown in numerous countries and cities. Strict social distancing also affects most of fields such as health, education, politics, religion, and economy. South Korea actively uses various digital technologies to fight against COVID-19, which is introduced internationally as a successful example. This article introduces the development background and functionalities of COVID-19 Epidemic Investigation Support System (EISS) as well as Smart City Datahub, the core technology that enables the rapid development and application of EISS. Moreover, based on this example, the role and importance of horizontal common platform, such as Datahub, are discussed in the view of future city.

• Steel and Composite Structures
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• v.52 no.2
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• pp.237-248
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• 2024

In order to make the dynamic analysis and design of improved composite beam with corrugated steel web (CBGSCC) bridge more efficient and economical, the parametric self-cyclic analysis model (SCAM) was written in Python on Anaconda platform. The SCAM can call ABAQUS finite element software to realize automatic modeling and dynamic analysis. For the CBGSCC bridge, parameters were set according to the general value range of CBGSCC bridge parameters in actual engineering, the SCAM was used to calculate the large sample model generated by parameter coupling, the optimal value range of each parameter was determined, and the sensitivity of the parameters was analyzed. The number of diaphragms effects weakly on the dynamic characteristics. The deck thickness has the greatest influence on frequency, which decreases as the deck thickness increases, and the deck thickness should be 20-25 cm. The vibration frequency increases with the increase of the bottom plate thickness, the web thickness, and the web height, the bottom plate thickness should be 17-23mm, the web thickness should be 13-17 mm, and the web height should be 1.65-1.7 5 m. Web inclination and Skew Angle should not exceed 30°, and the number of diaphragms should be 3-5 pieces. This method can be used as a new method for structural dynamic analysis, and the importance degree and optimal value range of each parameter of CBGSCC bridge can be used as a reference in the design process.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.4
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• pp.378-386
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• 2014

The use of bus stop in the center lane has reduced the emissions of exhaust gas on the road due to the improvement of the traffic speed but has caused a health problem for the citizens who are waiting for the bus in the platform, and thus the air pollution control of bus stop in the center lane is emerging as a more important part. This study was conducted to investigate the air pollution degree for the center lane-bus stops in four regions using mobile air measuring vehicle, and to evaluate the characteristics of air pollution by comparing with the data measured at the urban air monitoring site close to the bus stops. In addition, the correlation analysis was performed to analyze the impact to neighboring region by vehicle exhaust gas. The regional mean concentration of nitrogen dioxide in the center lane-bus stops ranged from 0.025 to 0.043 ppm which shows from 2.5 times to 5.3 times higher than the values of urban air monitoring site selected as a control group. The regional mean concentration of ozone in the center lane-bus stops ranged from 0.023 to 0.034 ppm which shows from 3% to 28% lower than the values of urban air monitoring site selected as a control group. The concentrations of nitrogen dioxide and ozone for the sampling regions did not exceed one hour-air quality environmental standard (0.1 ppm). The mean concentration of particulate matter for four center lane-bus stops was $28{\mu}g/m^3$ which shows about 27% higher than the values of urban air monitoring site selected as a control group, and that of particulate matter did not exceed one day-air quality environmental standard ($100{\mu}g/m^3$). In the results of correlation analysis between data from center lane-bus stops and data from urban air monitoring sites, the correlation coefficient (r) of nitrogen dioxide was relatively low as 0.316 to 0.416, and the correlation coefficient was high as the distance was close and vice versa. However, the correlation coefficient of ozone ranged from 0.167 to 0.658 and the correlation coefficient was high as the distance was far and vice versa.

• The Journal of Engineering Geology
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• v.24 no.3
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• pp.333-341
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• 2014

The construction of roads, tunnels, and bridges results in changes to the local terrain that may influence the ground safety factor, which represents the stability of geotechnical structures. In this study, we assessed construction sites that had collapsed as a result of terrain change, and then simulated variation in the ground safety factor with respect to terrain change caused by road construction. We assumed steep slopes to simulate changes in terrain in a mountainous area and assumed that earthworks took place for road construction by cutting a platform into the slope and altering the slope angle of the terrain both above and below the road. We calculated values of the ground safety factor through a stability analysis of the slope both above and below the road, and examined the variation in the safety factor of the above- and below-road slopes with respect to changes in road width. We found that if the slope angle was the same above and below the road, then the change in the ground safety factor during/after road construction occurred in the slope below the road, and if the slope angle above the road differed from that below, then the change occurred in both the above- and below-road slopes. Furthermore, the ground safety factor was essentially constant for road widths exceeding 2-6 m, depending on both above- and below-road slope angle. The findings of this study can be used to guide the management of construction sites and to assess changes in ground stability during road construction work, particularly in the early stages of earthworks, when the road width is narrow.

• Textile Coloration and Finishing
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• v.29 no.4
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• pp.247-255
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• 2017

Scutellaria Baicalensis(SB) is widely used in traditional and modern oriental medicine. It possesses several biology activities such as anti-oxidative, anti-inflammatory, antimicrobial and antiviral activities. In this study, a functional high density polyethylene (HDPE) fabric with antimicrobial properties was developed using zeolite microparticles as a SB extract delivery carrier. Zeolites loaded with SB extract were prepared by immersing in an SB extract aqueous solution. The average size of the SB extract-loaded zeolites was about 0.1 to $2.0{\mu}m$, and the morphology of the zeolites was not altered after SB extract binding. The resulting SB extract-loaded zeolites were then immobilized homogeneously onto the HDPE fabric using acrylic binder. The encapsulation efficiency of SB extract to the zeolite was more than 45%. The in vitro release test of SB extract-loaded zeolites containing HDPE fabrics showed release of 35% of the total SB extract by day 1 in a 24hours immersion study. Moreover, the SB extract-loaded zeolites containing HDPE fabrics showed effective antimicrobial activity against Streptococcus mutans, Staphylococcus aureus, and Klebsiella pneumoniae, indicating that this innovative delivery platform potently imparted antimicrobial activity to the HDPE fabric. In conclusion, the current study suggests that the HDPE fabric containing the SB extract-loaded zeolites microparticle carrier system has potential as an effective antimicrobial textile such as safety gloves, protective gloves etc.

• Journal of Microbiology and Biotechnology
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• v.21 no.8
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• pp.874-883
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• 2011

Many studies have shown that the steamed root of Rehmannia glutinosa (SRG), which is widely used in the treatment of various neurodegenerative diseases in the context of Korean traditional medicine, is effective for improving cognitive and memory impairments. The purpose of this study was to examine whether SRG extracts improved memory defects caused by administering scopolamine (SCO) into the brains of rats. The effects of SRG on the acetylcholinergic system and proinflammatory cytokines in the hippocampus were also investigated. Male rats were administered daily doses of SRG (50, 100, and 200 mg/kg, i.p.) for 14 days, 1 h before scopolamine injection (2 mg/kg, i.p.). After inducing cognitive impairment via scopolamine administration, we conducted a passive avoidance test (PAT) and the Morris water maze (MWM) test as behavioral assessments. Changes in cholinergic system reactivity were also examined by measuring the immunoreactive neurons of choline acetyltransferase (ChAT) and the reactivity of acetylcholinesterase (AchE) in the hippocampus. Daily administration of SRG improved memory impairment according to the PAT, and reduced the escape latency for finding the platform in the MWM. The administration of SRG consistently significantly alleviated memory-associated decreases in cholinergic immunoreactivity and decreased interleukin-$1{\beta}$ (IL-$1{\beta}$) and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) mRNA expression in the hippocampus. The results demonstrated that SRG had a significant neuroprotective effect against the neuronal impairment and memory dysfunction caused by scopolamine in rats. These results suggest that SRG may be useful for improving cognitive functioning by stimulating cholinergic enzyme activities and alleviating inflammatory responses.