• Korean Journal of Remote Sensing
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• v.28 no.4
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• pp.435-448
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• 2012

Evapotranspiration (ET) including evaporation from a land surface and transpiration from photosynthesis of vegetation is a sensitive hydrological factor with outer circumstances. Though both direct measurements with an evaporation pan and a lysimeter, and empirical methods using eddy covariance technique and the Bowen ratio have been widely used to observe ET accurately, they have a limitation that the observation can stand for the exact site, not for an area. In this study, remote sensing technique is adopted to compensate the limitation of ground observation using the Moderate Resolution Imaging Spectroradiometer (MODIS) multispectral sensor mounted on Terra satellite. We improved to evapotranspiration model based on remote sensing (Mu et al., 2007) and estimated Penman-Monteith evapotranspiration considering regional characteristics of Korea that was using only MODIS product. We validated evapotranspiration of Sulma (SMK)/Cheongmi (CFK) flux tower observation and calculation. The results showed high correlation coefficient as 0.69 and 0.74.

• Journal of Astronomy and Space Sciences
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• v.18 no.2
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• pp.101-108
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• 2001

Low resolution spectroscopic observations of leo-stationary satellites over the Korean peninsula have been carried out at the KyungHee Optical Satellite Observing Facility (KOSOF) with a 40cm telescope. We have observed 9 telecommunication satellites and 1 weather satellite of 6 countries. The obtained spectral data showed that satellites could be classified and grouped with similar basic spectral feature. We divided the 10 satellites into 4 groups based on spectral slop and reflectance. It is suggested that the material types of the satellites can be determined through spectral comparisons with the ground laboratory data. We will continuously observe additional geo-stationary satellites for the accurate classification of spectral features.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.8
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• pp.177-184
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• 2019

Recently, electric power usages and peak loads from buildings are increasing due to higher outdoor air temperatures and/or abnormal climate during the summer period. As one of the eco-friendly measures, a renewable energy system has been received much attention. Particularly, interest on a photovoltaic (PV) system using solar energy has been rapidly increasing in a building sector due to its broad applicability. In using the PV system, one of important factors is the PV efficiency. The normal PV efficiency is determined based on the STC(Standard Test Condition) and the NOCT(Nominal Operating Cell Temperature) performance test. However, the actual PV efficiency is affected by the temperature change at the module surface. Especially, higher module temperatures generally reduce the PV efficiency, and it leads to less power generation from the PV system. Therefore, the analysis of the relation between the module temperature and PV efficiency is required to evaluate the PV performance during the summer period. This study investigates existing algorithms for calculating module surface temperatures and analyzes resultant errors with the algorithms by comparing the measured module temperatures.

• KIPS Transactions on Computer and Communication Systems
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• v.6 no.8
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• pp.353-358
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• 2017

An electrical power utility, like an electrical power pole, includes various kinds of sensors for smart services. Temperature data is considered one of the important factors that can influence the smart operations of this utility. This study suggests a method for temperature data analysis for deciding the status of the smart electrical power utilities by using Kalman Filter and Ensemble Model. The suggested approach separates the temperature data according to the different positions of the temperature sensors of a utility, then uses Kalman Filter and Ensemble Model to analyse the characteristics of the temperature variation. With detailed processes, method explains the variation between an external temperature factor like weather temperature data and the sensed temperature data, and then, analysis the temperature data from each position of electrical power utilities. In this process, the suggested method uses Kalman Filter to remove error data and the ensemble model to find out mean value of every hour of electrical data. The result and discussion of temperature analysis were described clearly with the analysed results of electrical data. Finally, we were able to check the working condition of the power devices and the range of the temperature data foe each devices, which may help to indicate any causalities with respect to the devices in the utility pole.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.310-313
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• 2012

Recently, Land reclamation created agricultural land which is farming. Agricultural land which is farming have accident with frequency it is damage to crop of from brine. So, desalinization is the first priority prerequisite task in using the in reclaimed farm land. Vibrant research and technical development is working for reclaimed of desaliaization. But, Current technology is impossible desalinization of reclaimed land. As fast almost of people don't worry about concentration of salt in using the land reclamation of agricultural land irrigation water and river mouth of fountainhead of efforting from freshwater lake also ebb and flow of the tide land reclamation of agricultural land influnce from an increase of salt concentration by weather conditions and a malfunction of sea dike sluice In this paper, current is increased salt concentration in real time graphs were implemented to utilize external servers in using the WCDMA module. Inaddition it have to operate alarm in increase of salt concentration. besides, this program have implemented realtime concentration of salt monitoring system which save date in realtime the user can check again.

• Journal of Animal Environmental Science
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• v.9 no.1
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• pp.9-18
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• 2003

Most of broiler houses in Korea have the trouble of environmental control such as suitability, stability, and uniformity of internal climate, resulting in serious stress on chickens. Accordingly, it is very urgent to develop optimum designs of naturally and mechanically ventilated broiler houses for Korean climate. In this study, the internal climates such as air temperature, humidity, dust, ammonia gas, and air velocity were measured at a naturally ventilated broiler house. The data were collected during summer season including local weather data. It was found that the difference between measured and optimum air temperatures was $14.0^{\circ}C$ in maximum during the summer time. The daily maximum range of internal averaged air temperature was found $10.5^{\circ}C$ while the uniformity was $5.2^{\circ}C$ in maximum. The maximum, average, and minimum internal averaged relative humidity were 89.3%, 73.7%, and 49.2%, respectively while locally measured were 95.1% and 47.2%, respectively in maximum and minimum. Considering Temperature-humidity index, during summer season, over 97% of totally rearing period was shown that counter plan is needed for thermal stress while it was very dangerous situation for 22% of the rearing period. The ammonia gas and dust concentrations were seriously affected by the broilers activity, growth level, and relative humidity.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.560-565
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• 2002

In this paper, we implemented the sign board system that displays user's image, user's sentence, the information from DARC an[1 information based position by GPS module for vehicle. The existing sign board is displaying only user's image and sentence. Or other existing sign board is displaying the information via CDMA network. However, our system is also able to display the user's message like other system and gain the information more cheap by DARC. This system consists of 6 parts. The DARC control part classes the DARC information - news, weather, stock and time. The GPS control part gains moment and item to display with calculating the information of global position, direction, speed and satellite. The LED control part has two buffers to store and handle the image. The buffers help the system display various effected images on LED board. An external memory card includes the location based data, the option file and the displayed data files. The data files are stored by FAT 16 with the folder structure on external memory card. The USB controls the communication with PC. PC programs can control and monitor this system. This system is using G72l voice file format, for casting the information. This system was established at the vehicle and we monitored this system. The system displayed the DARC data , user's data and the location based data on the LED board, successfully.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.11
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• pp.123-132
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• 1998

This paper presents a road detection technique for spaceborne synthetic aperture radar (SAR) images. Roads are important cartographic features. We incorporate an active contour model called snake as a model for the road and define a new external energy for snake which is appropriate for the road. Detecting roads in spaceborne SAR images is very difficult without other information. In this paper, digital maps are utilized to obtain the initial position and shape for snake. Only approximate geodetic location of roads appearing in SAR images can be known through geocoding process and usual digital maps also have location errors. Therefore, there exist large location offsets between the two data. By introducing initial matching procedure, the errors are reduced significantly. Then we initialize the snake's shape using the roads extracted from digital map and minimize the energies of all snake points to detect roads. We outline two problems in detection and propose a method that mitigates them.

• Spatial Information Research
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• v.22 no.1
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• pp.27-33
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• 2014

Considering the wide coverage, the transparency from climate condition, Interferometric Synthetic Aperture Radar (InSAR) possesses a great potential for the landcover classification as shown in many precedent researches. In addition to the merits of InSAR products for the landcover classification, the time series analysis of InSAR pairs can provide a highly reliable basis to interpret landcover. We applied such idea with the test site in Mountain Baekdu located on the border between North Korea and China. Since it is recently noted as the potential volcanic activation site, the landcover especially the vegetation distribution information is highly essential to validate the reliability of Differential Interferometric Synthetic Aperture Radar (DInSAR) over Mt. Baekdu. The algorithms combining the auxiliary information from Moderate Resolution Imaging Spectroradiometer (MODIS) to analyze the phase coherence and backscatter coefficient of Observing Satellite (ALOS) Phased Array type L-band Synthetic Aperture Radar (PALSAR) was established. The results using InSAR signatures from two polarization modes of ALOS PALSAR showed high reliability for mining landcover and spatial distribution.

• Journal of Space Technology and Applications
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• v.1 no.2
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• pp.268-281
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• 2021

Recently, the synthetic aperture radar (SAR) has been increasingly in demand due to its advantage of being able to observe desired points regardless of time and weather. To utilize SAR data, first of all, many pre-processing such as satellite orbit correction, radiometric calibration, multi-looking, and geocoding are required. For analysis of SAR imagery such as object detection, change detection, and DEM(Digital Elevation Model), additional processings are needed. These pre-processing and additional processes are very complex and require a lot of time and computational resources. In order to handle the SAR images easily, the institutions that use SAR images develop analysis tools and provide users. This paper introduces the function and characteristics of representative SAR imagery analysis tools.