• Journal of the Semiconductor & Display Technology
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• v.21 no.1
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• pp.17-21
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• 2022

In the case of the manufacturing industry that produces high-tech components such as semiconductors and large flat panel displays, the manufacturing space is made into a cleanroom to increase product yield and reliability, and various environmental factors have been managed to maintain the environment. Among them, airborne particle is a representative management item enough to be the standard for actual cleanroom grade, and a sequential particle monitoring system is usually used as one parts of the FMS (Fab or Facility monitoring system). However, this method has a problem in that the measurement efficiency decreases as the length of the sampling tube increases. In this study, in order to solve this problem, a multiple regression model was created. This model can correct the measurement error due to the decrease in efficiency by sampling tube length.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.5
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• pp.480-485
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• 2013

Enhancing energy efficiency of machine tools causes substantial impacts on the manufacturing industries, to cope with the competitive introduction of the total energy management strategies. Real-time energy monitoring is essential to identify energy consumption patterns of the machine tools and correlate them with the energy management strategy. Integrated analysis of machine tool's operation status and the corresponding energy usage is most important to accurately evaluate the energy efficiency under the various machining process environments. This paper proposes a system architecture to realize the online energy monitoring system and the embedded energy monitoring approach interconnected with the CNC kernel. The shop-floor operation management system is presented to integrate the proposed online energy monitoring approach.

• International Journal of Highway Engineering
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• v.14 no.6
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• pp.57-65
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• 2012

PURPOSES : Efficiency Improvement of a public road construction project management work using the development of a real-time remote site monitoring system METHODS : In this study, we developed the remote site monitoring system using a web camera for road construction projects in the RCMA(Regional Construction Management Administration). We can be monitored a construction progress and a weak point of the situation in real time using this. To achieve this, we tested about 10 road construction projects ordered by RCMA. Then, we verified a applicability for the site monitoring system in future. RESULTS : Take advantage of the remote site monitoring system consists of the Construction CALS System, one of the business systems used in the part of the MLTM(Ministry of Land, Transport and Maritime Affairs) institution-agencies. Was configured to be served through the "Construction CALS System" of "Construction Management System(Contractors)" and the "Construction CALS Portal System". Through this, Benefit analysis through a pilot application of the 10 road construction sites and developing considerations and "Guide for visual information processing equipment installation-operating in construction sites"are presented. CONCLUSIONS : Through the establishment of remote site monitoring system can improve the efficiency of construction management services. In addition, Various disasters and calamities, accidents and illegal construction will be prevented in advance is expected. This is expected to further improve the quality of the facilities.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.7
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• pp.765-767
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• 2016

Building Energy commissioning is a process in which verifying and making the document during entire lifetime including planning, design, construction, test run of equipment, and maintenance to minimize the operational problems of building energy efficiency. The general commissioning is replacing the equipment or reconstructing the skin to achieve the performance for the design. This process is expensive and has the disadvantage of taking a long payback period by one operation. In this paper, we studied the monitoring-based commissioning (MBCx) to increase the energy efficiency of buildings through analyzing energy use data. MBCx is modeling a building energy, comparing the real energy use with it, detecting the cause of falling the efficiency, and running the optimal operation regularly.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2015.10a
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• pp.147-149
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• 2015

ECDIS(전자해도표시장치) 기반에 선박의 연료 효율성 모니터링 시스템인 SEEMS(Ship Energy Efficiency Monitoring System)를 연계하여 표시하고, 해상 기상 예보 정보를 도식화 하는 방법에 관하여 연구하였다.

• Particle and aerosol research
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• v.15 no.4
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• pp.191-202
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• 2019

In this study, performance (particle removal efficiency and breathing resistance) of several commercially available face masks (electrostatic filter masks (KF80 certified), a nanofiber filter mask (KF80 certified), and an uncertified mask) with their filter structure and composition were evaluated. Also, effects of relative humidity (RH) of incoming air, water and alcohol exposure, and reusability on performance of face masks were examined. Monodisperse and polydisperse sodium chloride particles were used as test aerosols. Except the uncertified mask filter, PM_2.5 removal efficiency was found to be higher than 90%, and the nanofiber filter mask had the highest quality factor due to the low pressure drop and high removal efficiency (nanofibers were arranged in a densely packed pore structure and contained a significant amount of fluorine in addition to carbon and oxygen). In the case of the KF80 certified mask, the removal efficiency was little affected when the RH of incoming air increased. When the mask filters were soaked in water, the removal efficiency of mask filters was degraded. In particular, the uncertified mask filter showed the highest removal efficiency degradation (26%). When the mask was soaked in alcohol, the removal efficiency also decreased with the greater degree than the water soaking case. The nanofiber mask filter showed the strongest resistance to alcohol exposure among tested mask filters. During evaluation of reusability of masks in real life, the removal efficiency of certified mask filter was less than 4% for 5 consecutive days (2 hours per day), while the removal efficiency of uncertified mask filter significantly decreased by 30% after 5 days.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3162-3167
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• 2007

The OPS (Optical Particle Sensor) using light scattering from the particles (real-time measurement without physical contact to the particles) can be used for cleanroom or atmospheric environment monitoring. For particles smaller than 300 nm, the detection efficiency becomes lower as scattered light decreases with particle size. To obtain higher detection efficiency with small particles, the flow field in particle chamber and the detection volume should be designed optimally to achieve maximum scattered light from the particles. In this study, a commercial computational fluid dynamics software FLUENT was used to simulate the gas flow field and particle trajectories with various optical chamber designs for 300 nm PSL particle. For estimation of laser viewing volume, we used a commercial computational optical design program ZEMAX. The results will be a great help in the development of OPS which can measure small particles with higher detection efficiency.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.627-632
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• 2002

One main purpose of environmental monitoring after oil spill is developing ESI (Environmental Sensitivity) Maps. Environmental impacts caused by the spilt oil are strongly depending upon the coastal topology and geology. Monitoring all impacted shorelines is almost impossible; using high-resolution satellite images such as IKONOS greatly contributes to improve the efficiency of on-site researches, at the same time, reliability of ESI maps.

• Journal of Sensor Science and Technology
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• v.24 no.2
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• pp.96-100
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• 2015

In the present study, we developed a real-time radiation-monitoring sensor for an underwater radiation-monitoring system and evaluated its effectiveness using reference radiation sources. The monitoring sensor was designed and miniaturized using a silicon photomultiplier (SiPM) and a cerium-doped-gadolinium-aluminum-gallium-garnet (Ce:GAGG) scintillator, and an underwater wireless monitoring system was implemented by employing a remote Bluetooth communication module. An acrylic water tank and reference radiation sources ($^{137}Cs$, $^{90}Sr$) were used to evaluate the effectiveness of the monitoring sensor. The underwater monitoring sensor's detection response and efficiency for gamma rays and beta particles as well as the linearity of the response according to the gammaray intensity were verified through an evaluation. This evaluation is expected to contribute to the development of base technology for an underwater radiation-monitoring system.

• Nuclear Engineering and Technology
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• v.46 no.6
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• pp.737-752
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• 2014

As condition-based maintenance (CBM) has risen as a new trend, there has been an active movement to apply information technology for effective implementation of CBM in power plants. This motivation is widespread in operations and maintenance, including monitoring, diagnosis, prognosis, and decision-making on asset management. Thermal efficiency analysis in nuclear power plants (NPPs) is a longstanding concern being updated with new methodologies in an advanced IT environment. It is also a prominent way to differentiate competitiveness in terms of operations and maintenance costs. Although thermal performance tests implemented using industrial codes and standards can provide officially trustworthy results, they are essentially resource-consuming and maybe even a hind-sighted technique rather than a foresighted one, considering their periodicity. Therefore, if more accurate performance monitoring can be achieved using advanced data analysis techniques, we can expect more optimized operations and maintenance. This paper proposes a framework and describes associated methodologies for in-situ thermal performance analysis, which differs from conventional performance monitoring. The methodologies are effective for monitoring, diagnosis, and prognosis in pursuit of CBM. Our enabling techniques cover the intelligent removal of random and systematic errors, deviation detection between a best condition and a currently measured condition, degradation diagnosis using a structured knowledge base, and prognosis for decision-making about maintenance tasks. We also discuss how our new methods can be incorporated with existing performance tests. We provide guidance and directions for developers and end-users interested in in-situ thermal performance management, particularly in NPPs with large steam turbines.