• Journal of Sensor Science and Technology
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• v.8 no.3
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• pp.253-258
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• 1999

This paper is written for the purpose of obtaining the information about the weather easily by the development of weather forecast system sensing temperature, humidity, and atmospheric pressure as key information. For this, data is obtained from the Weather Bureau, and analyzed in order to set a standard of weather forecast from the collected data. The pressure sensor and temperature-humidity sensor are fabricated using the piezoresistive effect of semiconductor, which are used to collect data. The weather forecast system is made using microprocessor.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.741-744
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• 2008

Quality control of early age concrete significantly influences the long term performance. Primary factors for early age concrete quality control should include the relative humidity and temperature variation, and these are more important as structures become massive and huge. Temperature raise due to cement hydration causes stress, which can develop to cracking with internal and/or external restraints. Exposure conditions including ambient temperature, humidity and wind also significantly affect the cracking behavior of early age concrete. Among many of studies on the early age concrete behavior, investigation on the variation of temperature and relative humidity internal of concrete is not common. That is in part because the difficulties in measuring the relative humidity and temperature inside the concrete. This study used a digital sensor with an appropriate logger to measure internal temperature and relative humidity. This direct measuring method is expected to provide more reliable and comprehensive data acquisition on the early age behavior of concrete.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.570-576
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• 2020

This study uses beacons and smartphone Global Positioning System (GPS) receivers to establish a location-based disaster/hazard prediction system. Beacons are usually installed indoors to locate users using triangulation in the room, but this study is differentiated from previous studies because the system is used outdoors to collect information on registration location and temperature and humidity in hazardous areas. In addition, since it is installed outdoors, waterproof, dehumidifying, and dustproof functions in the beacons themselves are required, and in case of heat and humidity, the sensor must be exposed to the outside, so the waterproof function is supplemented with a separate container. Based on these functions, information on declining and vulnerable areas is identified in real time, and temperature/humidity information is collected. We also propose a system that provides weather and fine-dust information for the area concerned. User location data are acquired through beacons and smartphone GPS receivers, and when users transmit from declining or vulnerable areas, they can establish the data to identify dangerous areas. In addition, temperature/humidity data in a microspace can be collected and utilized to build data to cope with climate change. Data can be used to identify specific areas of decline in a microspace, and various analyses can be made through the accumulated data.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.732-740
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• 2019

Evaporative humidification using a humidifying element is widely used for humidification of a building or a data center. The performance of a humidifying element is commonly expressed as humidification efficiency, which is used independent of air temperature, humidity and water temperature. In this study, a series of tests were conducted at two air conditions (data center and commercial building) using two different humidifying elements (cellulose/PET and Glasdek) changing the frontal air velocity and water temperature. Results showed that the measured humidification efficiency was dependent on the air condition and water temperature. In fact, even dehumidification occurred at the inlet of the humidifying element at the air condition of commercial building. The reason was due to the inlet water temperature, which was lower than the dew point air temperature. As the difference between the inlet water and the dew point air temperature increased, the humidification efficiency decreased. This suggest that proper thermal model should account for the inlet region, where the amount of moisture transfer may be different from the other part of the humidification element. A simple analysis on the thermal performance of the cellulose/PET humidification element showed that the Sherwood number was adequately predicted, whereas the friction factor was ovepredicted, probably due to the simplification of the channel geometry and the neglection of the water film on the element surface.

• Journal of Conservation Science
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• v.32 no.4
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• pp.491-500
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• 2016

Fog is atmospheric in which tiny drops of water vapor are suspended in the air near the ground. Its form, occurrence, etc., change according to the temperature, relative humidity, wind and geographical features of the space around it. In particular, fog tends to occur near a source of water because of temperature and relative humidity difference. These days, climate change is increasingly affecting the occurrence of fog. Therefore the purpose of this study was to investigate how fog affects materials that are part of our cultural properties through outdoor exposure tests and artificial degradation. The degradation evaluation of materials as a function of fog occurrence frequency, showed that the color of metals changed noticeably, whereas dyed silk and Dancheong showed degradation on the surface and color differences but no particular tendencies. Therefore, damage prediction by color differences as a function of fog occurrence frequency was based on metal samples, which showed constant color differences. Through a comparison of the predictive value and color difference by outdoor exposure, the accuracy and applicability of the damage prediction formula was confirmed. If a more complex damage prediction formula is created, it is expected that prediction of the degree of material damage in the field would be possible.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.9
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• pp.1151-1158
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• 2013

Knowledge of the moisture sorption properties of a material is essential for optimal material development and analysis of the delamination failure caused by vapor pressure at the interlayer during the manufacturing process of integrated packaging devices. In this paper, both temperature dependent absorption and desorption properties according to temperature and humidity model are parameterized and the effects of water activities and temperature are discussed. The activation energy obtained from the parameterized diffusivity determines the acceleration factor for the equivalency of moisture sorption levels, which enables the effect of moisture diffusivity on the equivalent elapsed testing time required for evaluating the reliable life time to be estimated. The acceleration factor evaluated at the reliability testing standard of the flexible packaging module is exampled.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4D
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• pp.593-600
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• 2006

Joint opening of jointed concrete pavement is caused by change in temperature and humidity of adjoined slab. The magnitude of joint opening influences on the load-transfer-efficiency and the behavior of sealant. If temperature or humidity decreases, joint opening increases. Generally maximum joint opening of a given joint is predicted by using AASHTO equation. While different magnitudes of joint opening at the individual joints have been observed in a given pavement section, AASHTO equation is limited to predict average joint opening in a given pavement section. Therefore the AASHTO equation may underestimate maximum joint for the half of joint in a given pavement section. Joints showing larger opening than the designed may experience early joint sealant failure, early faulting. Also unexpected spalling may be followed due to invasion of fine aggregate into the joints after sealant pop-off. In this study, the variation of the joint opening in a given pavement section was investigated based on the LTPP SMP data. Factors affecting on the variation are explored. Finally a probabilistic joint opening model is developed. This model can account for the reliability of the magnitude of joint opening so that the designer can select the ratio of underestimated joint opening.

• Journal of Advanced Technology Convergence
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• v.1 no.1
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• pp.1-6
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• 2022

Since 2015, the government has been making efforts to distribute Korean smart farms. However, the supply is limited to large-scale facility vegetable farms due to the limitations of technology and current cultivation research data. In addition, the efficiency and reliability compared to the introduction cost are low due to the simple application of IT technology that does not consider the crop growth and cultivation environment. Therefore, in this paper, data analysis services was performed based on public and external data. To this end, a data-based target smart farm system was designed that is suitable for the situation of farms growing in facilities. To this end, a farm risk information notification service was developed. In addition, light environment maps were provided for proper fertilization. Finally, a disease prediction model for each cultivation crop was designed using temperature and humidity information of facility farms. Through this, it was possible to implement a smart farm data service by linking and utilizing existing smart farm sensor data. In addition, economic efficiency and data reliability can be secured for data utilization.

• Korean Journal of Environmental Biology
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• v.40 no.2
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• pp.214-223
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• 2022

Among migratory insect pests, Mythimna seperata and Cnaphalocrocis medinalis are invasive pests introduced into South Korea through westerlies from southern China. M. seperata and C. medinalis are insect pests that use rice as a host. They injure rice leaves and inhibit rice growth. To understand the distribution of M. seperata and C. medinalis, it is important to understand environmental factors such as temperature and humidity of their habitat. This study predicted current and future habitat suitability models for understanding the distribution of M. seperata and C. medinalis. Occurrence data, SSPs (Shared Socio-economic Pathways) scenario, and RCP (Representative Concentration Pathway) were applied to MaxEnt (Maximum Entropy), a machine learning model among SDM (Species Distribution Model). As a result, M. seperata and C. medinalis are aggregated on the west and south coasts where they have a host after migration from China. As a result of MaxEnt analysis, the contribution was high in the order of Land-cover data and DEM (Digital Elevation Model). In bioclimatic variables, BIO_4 (Temperature seasonality) was high in M. seperata and BIO_2 (Mean Diurnal Range) was found in C. medinalis. The habitat suitability model predicted that M. seperata and C. medinalis could inhabit most rice paddies.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.134-134
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• 2017

전북지역의 130여개 스마트온실 중에서 주요한 10여개의 주요 온실에 대한 온습도, 이산화탄소, 광센서 및 기타 센서의 사용실태에 대한 조사를 수해하였다(2016년 9월~12월). 온실의 선정은 온실의 종류(비닐/유리)와 복합제어기 종류(국산/외산)를 중심으로 조사하였다. 국내외 업체의 장단점, 스마트기기의 활용과 문제점, 클라우드 기반의 3세대 한국형 스마트온실의 적용기반에 대한 조사를 수행하였다. 융복합 제어기와 센서는 자체의 신뢰성 이외에 운용상의 알고리즘 차이에서 오는 문제로 인해 농가에서 측정결과에 대한 신뢰성이 낮고, 측정이 부정확하고 일일측정 데이터에 대한 활용이 어렵고, 설정 값을 사용자가 직접 계산하고 값들을 입력해주어야 한다는 단점에 대한 의견이 대부분이다. 외국 제품은 데이터 측정값의 활용이 용이하고 복합 환경 상황에 알맞게 자동 계산 시스템이 체계적으로 작동하여 제어에 반영되며 국내 업체 설정 값의 범위보다 세밀하게 설정이 가능하다는 장점이 있으나 설치비용이 국내대비 3~4배 높고 고장 시 A/S가 느린 편이며 영어로 구성된 복잡한 시스템이기 때문에 100% 활용하기 어렵다는 단점이 있다. 스마트기기 활용은 복합 환경제어를 하는 농가이면 국내 업체와 외국 업체 모두 활용하고 있으며 주로 스마트 폰으로 사용되고 전용 어플이 아닌 PC원격 제어 소프트웨어인 팀뷰어(Teamviewer)를 이용하여 복합제어기 PC를 직접 조작하여 사용한다. 클라우드 활용으로는 복합환경제어기 회사에서 작물별 제어 방법과 데이터 정보를 제공하지 않는 점에 대한 농가의 불편함이 많은 편으로 작물별 농사방법이 많고 지역별 농사방법이 다르기 때문에 조사한 전북지역의 농가 10곳 모두 클라우드를 사용하지 않는 것으로 조사되었다. 다양한 온실 및 생육환경에 따른 표준화된 운영의 문제점을 개선하여 스마트팜에서 중요한 역할을 수행하는 복합센서의 표준시험방법과 절차를 개발하여 관련산업의 발전에 응용할 필요성이 있으며 단순한 하드웨어의 표준화 또는 개선방향보다는 농가의경험과 누적된 토양,작물 등의 재배 생육정보를 이용한 작물생육모델과 온실모델의 일치를 통해 센서-생육환경예측-검증방법의 포준화가 필요한 것으로 사료된다.