• Journal of the Korean Chemical Society
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• v.33 no.1
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• pp.90-96
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• 1989

A new series of $dioxo-di-{\mu}-oxo-dimolybdate(V)(*image)$, has been prepared by the reaction of pyridinum oxoisothiocyanato-molybdate(V) with 1, 6-diaminohexane-N, N, N', N'-tetraacetic acid derivatives containing amine carboxyl groups. The properties and possible molecular structure of these complexes were discussed by elemental analysis, spectroscopic studies and magnetic susceptibility measurements. The infrared spectra of these complexes show two strong Mo=$O_t$ stretching modes in the $900-965cm^{-1}$, MoO$_2$Mo stretching bands at around 450∼500 and $740-765 cm^{-1}$ to symmetrical and asymmetrical O-bridge stretching, a coordinated $COO^-$ asymmetrical band in the $1600-1635 cm^{-1}$. The complexes synthesized were yellow or orange and diamagnetic.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.8
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• pp.636-645
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• 2017

A scanning radar is exploited widely such as for ground surveillance, disaster rescue, and etc. However, the range resolution is limited by transmitted bandwidth and cross-range resolution is limited by beam width. In this paper, we propose a method for super-resolution radar imaging. If the distribution of reflectivity is sparse, the distribution is called sparse signal. That is, the problem could be formulated as compressive sensing problem. In this paper, 2D super-resolution radar image is generated via reweighted ${\ell}_1-Minimization$. In the simulation results, we compared the images obtained by the proposed method with those of the conventional Orthogonal Matching Pursuit(OMP) and Synthetic Aperture Radar(SAR).

• Journal of Biomedical Engineering Research
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• v.32 no.2
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• pp.127-133
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• 2011

Arteria radialis is a branch of the brachial artery extending down the forearm around the wrist where it closes to skin surface. In the oriental medicine, the skin above arteria radialis has an important role because oriental medicine practitioners put their finger tips on the area, and diagnose patient's health conditions by feeling the pulsation of the arterial contraction. The finger tip diagnostic method relies on subjective decision of the practitioner; and there is a need to develop an objective diagnostic modality. The pulsation of the arterial contraction appears not only a movement on the site but also as temperature fluctuation due to pulsatile feeding of warmer blood. The goal of this study is to demonstrate a feasibility of using an infrared camera quantitatively to detect the temperature fluctuation on the skin. Clinical important three different areas, called chon, gwan, chuk, near a wrist where the arteria radialis reaches close to skin surface are marked with small pieces of surgical tape. A high-speed and high-resolution infrared camera with a 3 cm of field of view measures these areas for 10 second at 200 frames per second with a 320*240 pixel size. The pulsatile temperature fluctuation is calculated after passing a band pass filter to remove any stationary temperature over 10 second. The temperature fluctuation of a healthy male volunteer is measured at a room temperature as a control, and is compared with another measurement performed after 20 minutes staying in a room at a 40 degree Celsius. This comparison is repeated for three times, and indicates that the fluctuation increases after staying 20 minutes in the warm room. This increase becomes smaller when the person stays in the warm room with an acupuncture treatment that decreases body temperature. So that an objective diagnostics on the site may become feasible.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.32 no.4_1
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• pp.327-333
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• 2014

To improve thermal environments in urban area, the structural characteristic analysis of thermal environments of the certain area should be preceded to analyze and supplement its problems. With Landsat-8, we measured the centrality estimation, the distribution map, and the spatial statistical analysis of Daegu Metropolitan City in January and August, which of data applied in analyzing the structure of thermal environments following to its spatial property. The thermal infrared band of satellite images has been used to analyze the standard normal deviated scores, which extract the centrality, while the cluster map, based upon Local Local Moran's I, has composed for understanding the autocorrelation of local spatial within environment space structure. Understanding the distribution features as well as the pivot center of thermal environments with satellite images provides principle database for updating urban thermal environments' policies and plans; because those are reference materials that should have precedence over for diverse thermal environment policies.

• Korean Journal of Remote Sensing
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• v.20 no.5
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• pp.337-351
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• 2004

Our laboratory originally developed the compact, multi-spectral, automatic aerial photographic system PKNU3 to allow greater flexibility in geological and environmental data collection. We are currently developing the PKNU3 system, which consists of a color-infrared spectral camera capable of simultaneous photography in the visible and near-infrared bands; a thermal infrared camera; two computers, each with an 80-gigabyte memory capacity for storing images; an MPEG board that can compress and transfer data to the computers in real-time; and the capability of using a helicopter platform. Before actual aerial photographic testing of the PKNU3, we experimented with each sensor. We analyzed the lens distortion, the sensitivity of the CCD in each band, and the thermal response of the thermal infrared sensor before the aerial photographing. As of September 2004, the PKNU3 development schedule has reached the second phase of testing. As the result of two aerial photographic tests, R, G, B and IR images were taken simultaneously; and images with an overlap rate of 70% using the automatic 1-s interval data recording time could be obtained by PKNU3. Further study is warranted to enhance the system with the addition of gyroscopic and IMU units. We evaluated the PKNU 3 system as a method of environmental remote sensing by comparing each chlorophyll image derived from PKNU 3 photographs. This appraisement was backed up with existing study that resulted in a modest improvement in the linear fit between the measures of chlorophyll and the RVI, NDVI and SAVI images stem from photographs taken by Duncantech MS 3100 which has same spectral configuration with MS 4000 used in PKNU3 system.

• Korean Journal of Remote Sensing
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• v.26 no.5
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• pp.465-475
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• 2010

Spectral library is a database that archives spectral reflectance and related metadata of earth surface materials. Spectral library plays important role to assist analyzing several types of remote sensor data, to determine suitable wavelength band for detecting a certain material, and to classify hyperspectal image data. This paper describes the structure and content of a spectral library that is suitable for the environment of the Korea peninsula while existing spectral libraries have certain limitations to apply for surface materials covering the region. We designed a spectral library that includes vegetation and man-made materials indigenous to the region. The spectral library also includes spectra of mineral and rock, soil, liquid, and some man-made materials from existing spectral libraries. Newly augmented spectra of vegetation and man-made materials were obtained by spectral measurements in laboratory and field. The spectral library viewer was developed to increase efficiency of usage and searching.

• Korean Journal of Remote Sensing
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• v.15 no.2
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• pp.107-117
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• 1999

A comparison of a neural network approach with the conventional statistical methods, multiple regression and band ratio analyses, for the estimation of water quality parameters in presented in this paper. The Landsat TM image of Lake Daechung acquired on March 18, 1996 and the thirty in-situ sampling data sets measured during the satellite overpass were used for the comparison. We employed a three-layered and feedforward network trained by backpropagation algorithm. A cross validation was applied because of the small number of training pairs available for this study. The neural network showed much more successful performance than the conventional statistical analyses, although the results of the conventional statistical analyses were significant. The superiority of a neural network to statistical methods in estimating water quality parameters is strictly because the neural network modeled non-linear behaviors of data sets much better.

• Korean Journal of Remote Sensing
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• v.16 no.4
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• pp.305-313
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• 2000

A vicarious calibration method was developed for the OSMI sensor calibration. Employing measured aerosol optical thickness by a sunphotometer and a sky radiometer and water leaving radiance by ship measurements as inputs, TOA (top of the atmosphere) radiance at each OSMI band was simulated in conjunction with a radiative transfer model (Rstar5b) by Nakajima and Tanaka (1988). As a case of examining the accuracy of this method, we simulated TOA radiance based on water leaving radiance measured at NASA/MOBY site and aerosol optical thickness estimated nearby at Lanai, and compared simulated results with SeaWiFS-estimated TOA radiances. The difference falls within about $\pm$5%, suggesting that OMSI sensor can be calibrated with the suggested accuracy. In order to apply this method for the OSMI sensor calibration, ground-based sun photometry and ship measurements were carried out off the east coast of Korean peninsula on May 31, 2000. Simulations of TOA radiance by using these measured data as input to the radiative transfer model show that there are substantial differences between simulated and OSMI-estimated radiances. Such a discrepancy appears to be mainly due to the cloud contamination because satellite image indicates optically thin clouds over the experimental area. Nevertheless results suggest that sensor calibration can be achieved within 5% uncertainty range if there are ground-based measurements of aerosol optical thickness, and water leaving radiances under clear-sky and optically thin atmospheric conditions.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.10
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• pp.720-727
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• 2019

Resonating thermal lags of solid fuel with heat transfer oscillations generated by boundary layer oscillation is the primary mechanism of the occurrence of the LFI (Low Frequency Combustion Instability) in hybrid rocket combustion. This study was experimentally attempted to confirm that how the boundary layer was perturbed and led to the LFI. Special attention was also made on oxidizer swirl injection to investigate the contribution to combustion stabilization. Also the overall behavior of fluctuating boundary layer flow and the occurrence of the LFI was monitored as swirl intensity increased. Fluctuating boundary layer was successfully monitored by the captured image and POD (Proper Orthogonal Decomposition) analysis. In the results, oscillating boundary layer became stabilized as the swirl intensity increases. And the coupling strength between high frequency p', q' diminished and periodical amplification of RI (Rayleigh Index) with similar frequency band of thermal lag was also decreased. Thus, results confirmed that oscillating axial boundary layer triggered by periodic coupling of high frequency p', q' is the primary mechanism to excite thermal resonance with thermal lag characteristics of solid fuel.

• Korean Journal of Remote Sensing
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• v.38 no.5_1
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• pp.545-557
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• 2022

This study used high-resolution satellite images and supervised classification technique based on machine learning method in order to detect the areas affected by wildfires in the demilitarized zone (DMZ) where direct access is difficult. Sentinel-2 A/B was used for high-resolution satellite images. Land cover map was calculated based on the SVM supervised classification technique. In order to find the optimal combination to classify the DMZ wildfire damage area, supervised classification according to various kernel and band combinations in the SVM was performed and the accuracy was evaluated through the error matrix. Verification was performed by comparing the results of the wildfire detection based on satellite image and data by the wildfire statistical annual report in 2020 and 2021. Also, wildfire damage areas was detected for which there is no current data in 2022. This is to quickly determine reliable results.