• Journal of Sensor Science and Technology
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• v.17 no.3
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• pp.183-187
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• 2008

A sub-ppm level MEMS gas sensor that can be used for the detection of formaldehyde (HCHO) is presented. It is realized by using a zinc oxide (ZnO) thin-film material with a Ni-seed layer as a sensing material and by bulk micromachining technology. To enhance sensitivity of the MEMS gas sensor with Ni-seed layer was embedded with ZnO sensing material and sensing electrodes. As experimental results, the changed sensor resistance ratio for HCHO gas was 9.65 % for 10 ppb, 18.06 % for 100 ppb, and 35.7 % for 1 ppm, respectively. In addition, the minimum detection level of the fabricated MEMS gas sensor was 10 ppb for the HCHO gas. And the measured output voltage was about 0.94 V for 10 ppb HCHO gas concentration. The noise level of the fabricated MEMS gas sensor was about 50 mV. The response and recovery times were 3 and 5 min, respectively. The consumption power of the Pt micro-heater under sensor testing was 184 mW and its operating temperature was $400^{\circ}C$.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.35-38
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• 2004

We developed a Near Real-Time Validation System (NRVS) for the Level-2 Products of AQUA Satellite. AQUA satellite is the second largest project of Earth Observing System (EOS) mission of NASA. This satellite provides the information of water cycle of the entire earth with many different forms. Among its products, we have used five kinds of level-2 geophysical parameters containing rain rate, sea surface wind speed, skin surface temperature, atmospheric temperature profile, and atmospheric humidity profile. To use these products in a scientific purpose, reasonable quantification is indispensable. In this paper we explain the near real-time validation system process and its detail algorithm. Its simulation results are also analyzed in a quantitative way. As reference data set in-situ measured meteorological data which are periodically gathered and provided by the Korea Meteorological Administration (KMA) is processed. Not only site-specific analysis but also time-series analysis of the validation results are explained and detail algorithms are described.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.10
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• pp.6517-6526
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• 2015

This study analyzes the technical level and shows the priority technology for suspension bridges that play an iconic role as the country's landmark and contain an economic value. Analysis results show the technical level of suspension bridge is 82 percent compared to developed countries. In detail, the technical levels of 'materials', 'planning and design', and 'construction and maintenance' are 80.2 %, 81.7%, and 83.7% respectively. This study analyzes economic, social, technical importances and presents 'high-performance packaging material' as a priority technology.

• Journal of Korean Society for Quality Management
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• v.41 no.3
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• pp.395-404
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• 2013

Purpose: Technology readiness assessment(TRA) used as a standard readiness assessment tool in the acquisition program of weapon system has some limitations in the comprehensive understanding of the complex system. Therefore, this research is intended to suggest a holistic maturity assessment method for the acquisition of high quality weapon system. Methods: Technology readiness level(TRL), manufacturing readiness level(MRL), integration readiness level(IRL) and system readiness level(SRL) developed to assess system maturities in the various aspects are compared and analyzed to draw an improvement avenue for the current readiness assessment method. Results: TRL, MRL, IRL and SRL have large differences in their maturity targets during the acquisition life cycle: technological performance, manufacturing capability, interface between components and total system, respectively. They complement one another's shortcomings Conclusion: To achieve a successful acquisition of high quality weapon system, multi-dimensional readiness assessment is required. Therefore, comprehensive readiness assessment using TRL, MRL, IRL and SRL will contribute to the acquisition of high quality weapon system through the accurate maturity information of overall system.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.1
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• pp.107-111
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• 2006

This study was to verity that the uptake inhibition and accumulation of nitrogen in different potassium levels. Lettuce was used as model plant in this study and grown in pot of 10cm's in diameter and depth with mixture media of vermiculite and perlite under supply of different culture solution for three weeks. Nitrogen absorption at root was inhibited by increased potassium concentration in nutrient solution, and nitrate accumulation of plant was depended on absorption of nitrogen because nitrate content of 0 K level was 4-5 times higher than that of 2 K level, Concentration of ascorbic acid was decreased by increasing the nitrogen absorption, since ascorbic acid (AsA) content of 2K level was higher than those of OK level in both of old leaf and flesh leaf.

• Educational Technology International
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• v.19 no.1
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• pp.153-173
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• 2018

The purpose of this study was to investigate teaching competence of faculty members based on TPACK which should be examined to ensure high quality in higher education. This study was conducted with a focus on TPACK, which integrate technology knowledge (TK), content knowledge (CK), and pedagogy knowledge (PK). Except insincere responses data from a total of 85 participants were used for data analysis in this study. K-mean cluster analysis method was used to examine how faculty members could be distinguished depending on TPACK type. Study results showed that there were three different types of faculty groups (well-balanced competence type, development required competence type, and lack of technology competence type). First, faculty members defined as well balanced competence type were more than the average level in TPACK. Second, faculty members belonged to development required competence type reported below the average level in TPACK. Thus, faculty members in this type were required to increase teaching competence. Finally, faculty members in lack of technology competence type were needed to enhance competence related to technology because their overall TK level was relatively low. This study examined what distinctive characteristics exited in each type depending on gender, teaching career, nationality, and age. Results from this study offered a basis for better understanding TPACK for enhancing teaching competence at the university level.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.31-31
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• 2023

During December 2022, the northeast monsoon, which dominates the south and the Gulf of Thailand, had significant rainfall that impacted the lower southern region, causing flash floods, landslides, blustery winds, and the river exceeding its bank. The Golok River, located in Narathiwat, divides the border between Thailand and Malaysia was also affected by rainfall. In flood management, instruments for measuring precipitation and water level have become important for assessing and forecasting the trend of situations and areas of risk. However, such regions are international borders, so the installed measuring telemetry system cannot measure the rainfall and water level of the entire area. This study aims to predict 72 hours of water level and evaluate the situation as information to support the government in making water management decisions, publicizing them to relevant agencies, and warning citizens during crisis events. This research is applied to machine learning (ML) for water level prediction of the Golok River, Lan Tu Bridge area, Sungai Golok Subdistrict, Su-ngai Golok District, Narathiwat Province, which is one of the major monitored rivers. The eXtreme Gradient Boosting (XGBoost) algorithm, a tree-based ensemble machine learning algorithm, was exploited to predict hourly water levels through the R programming language. Model training and testing were carried out utilizing observed hourly rainfall from the STH010 station and hourly water level data from the X.119A station between 2020 and 2022 as main prediction inputs. Furthermore, this model applies hourly spatial rainfall forecasting data from Weather Research and Forecasting and Regional Ocean Model System models (WRF-ROMs) provided by Hydro-Informatics Institute (HII) as input, allowing the model to predict the hourly water level in the Golok River. The evaluation of the predicted performances using the statistical performance metrics, delivering an R-square of 0.96 can validate the results as robust forecasting outcomes. The result shows that the predicted water level at the X.119A telemetry station (Golok River) is in a steady decline, which relates to the input data of predicted 72-hour rainfall from WRF-ROMs having decreased. In short, the relationship between input and result can be used to evaluate flood situations. Here, the data is contributed to the Operational support to the Special Water Resources Management Operation Center in Southern Thailand for flood preparedness and response to make intelligent decisions on water management during crisis occurrences, as well as to be prepared and prevent loss and harm to citizens.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.794-798
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• 1997

We provide a set of information on technologies to draw meaningful action plans for the inter- nationalization of National R&D activities. In this study, we employed a modified Delphi method to evaluate level od our technological capabilities and developed countries' as well. We investigated technology acquistion methodologies,technology characteristics and various aspects of international cooperation in terms of technology. Then we analyzed final responses of participants (i.e, the third round results of Delphi method) to see the correlation among various factors in developing tehnologies through international R&D cooperation. The technology classification used in this research was developed by STEPI (Science and Technology Policy Institute). In conclusion, levels of our technologies were investigated to be between the stage of imitating/absorbing advanced technologies and the stage of digesting acquired technologies. Especially, comparing with other technologies, mechanical engineering was evaluated to be almost near the stage of digesting acquired technology (the middle level stage of technology). Out overal technological capabilites were evaluated to be 40~60% of top level countries'.

• Proceedings of the Technology Innovation Conference
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• 1999.12a
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• pp.159-177
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• 1999

Many companies still struggle with the issue of research and development(R&D) performance measurement, in particular, the nonfinancial performance measurement of R&D with coming of knowledge-based society, Of course, we would not deny the fact that financial measures play the central role in assessing the overall performance of R&D, The aim of this paper is to provide the new model to evaluate the quantitative value of technology (nonfinancial benefits). This new model is based on the technology stock(technology level) acquired in R&D process, That is, we take it for granted that the acquired technology below a certain level(<70% compare to the advanced country) can not be utilized in developing the new products or in proving the manufacturing processes, The evaluation model we create can explains the quantitative relation between the technology stock and the market value considering R&D expenditure to acquire the technology above certain level(>70%) and cost to prevent the technology obsolescence. The value of non-destructive testing technology, which is one of the electric Power technology, is measured quantitatively using our new model as a case study, We also discussed briefly the possibility of capitalization of the measured technology value.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.7
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• pp.45-58
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• 1996

We provide a set of information on technologies in the area of mechanical engineering to draw meaningful action plans for the internationalization of National R&D activities. In this study, we employed a modified Delphi method to evaluate levels of our technoligical capabilities and developed countries' as well. We investigate technology acquistion methodologies, technology charcteristics and various aspects of interna- tional cooperation in terms of technology. Then, we analyzed final responses of participants(i.e., the third round results of Delphi method) to see the correlation among various factors in developing mechanical engineeing technologies through international cooperation. The technology classification used in this research was devel- oped by STEPI(Science and Technology Policy Institute). In conclusion, our mechanical engineering technology is investigated to be below the middle level stage of technology(i.e., the stage of digesting acquired technologies) except the shipbuilding equipments technology which is evaluated to be on the top level stage of technology.