• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.103-110
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• 2018

Infrared signatures emitted from naval ships are mainly classified into internal signatures generated by the internal combustion engine of the ship and external signatures generated from the surface of the ship heated by solar heat. The internal signatures are also affected by the chemical components ($CO_2$, $H_2O$, CO and soot) of the exhaust plumes generated by the gas turbine and diesel engine, which constitute the main propulsion system. Therefore, in this study, the chemical composition ratios of the exhaust plumes generated by the gas turbines and diesel engines installed in domestic naval ships were examined to identify the chemical components and their levels. The influence of the chemical components of the exhaust plumes and their ratios on the infrared signatures of a naval ship was investigated using orthogonal arrays. The infrared signature intensity of the exhaust plumes calculated using infrared signature analysis software was converted to the signal-to-noise ratio to facilitate the analysis. The signature analysis showed that $CO_2$, soot and $H_2O$ are the major components influencing the mid-wave infrared signatures of both the gas turbine and diesel engine. In addition, it was confirmed that $H_2O$ and $CO_2$ are the major components influencing the long-wave infrared signatures.

• Journal of Biomedical Engineering Research
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• v.36 no.5
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• pp.228-234
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• 2015

The balance ability significantly decreased in the elderly because of deterioration of the neural musculature regulatory mechanisms. Several studies have investigated methods of improving balance ability using real-time systems, but it is limited by the expensive test equipment and specialized resources. Recently, Kinect system based on depth data has been applied to address these limitations. Little information about accuracy/inaccuracy of Kinect system is, however, available, particular in motion analysis for evaluation of effectiveness in rehabilitation training. Therefore, the aim of the current study was to evaluate accuracy/inaccuracy of Kinect system in specific rotational movement for balance rehabilitation training. Six healthy male adults with no musculoskeletal disorder were selected to participate in the experiment. Movements of the participants were induced by controlling the base plane of the balance training equipment in directions of AP (anterior-posterior), ML (medial-lateral), right and left diagonal direction. The dynamic motions of the subjects were measured using two Kinect depth sensor systems and a three-dimensional motion capture system with eight infrared cameras for comparative evaluation. The results of the error rate for hip and knee joint alteration of Kinect system comparison with infrared camera based motion capture system occurred smaller values in the ML direction (Hip joint: 10.9~57.3%, Knee joint: 26.0~74.8%). Therefore, the accuracy of Kinect system for measuring balance rehabilitation traning could improve by using adapted algorithm which is based on hip joint movement in medial-lateral direction.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.108.1-108.1
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• 2014

Near-infrared Imaging Spectrometer for Star formation history (NISS), one of the main payloads of NEXTSat-1, is being developed by Korea Astronomy & Space Science Institute (KASI). Since NISS adopts an infrared reflecting optical system, its performance is highly sensitive to changes in system temperature. Therefore, it is important to figure out the temperature through thermal analysis and cooling tests in order to optimize the optical system design. We conducted thermal analysis of NISS for the recently updated model, and obtained steady state temperature of the optical system for two cases of satellite attitude: about 190 K for the Normal case and about 210 K for the Hot case. In this paper, we present thermal design of NISS and the preliminary thermal analysis results.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1269-1269
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• 2001

The Bovine Spongiform Encephalopathy (BSE) is one of the more important problems that have affected the economy of european cattles and the Public Safety. Their transmission is mainly through digestive system, and the compound feeds made with animal proteins are one source of infection for healthy cows. Nowadays the official method for meat and bone meal (MBM) detection in compound feeds is a microscopy technique. However, this methodology is subjective, and that alter the fact to make one exhaustive quantitative analysis and one differentiation between mammalian and poultry bones. In addition, the separation of the differents fractions in a sample by density before the analysis, requires the use of organochlorates products as $CCl_4$, which produce serious damages in the atmosphere ozone content. NIR methodology is another possible way to confirm and identifying animal ingredients in compound feeds, Its capabilities for quantitative and qualitative analysis of foods and feeds has been enought demonstrated. The objective of this work was to use NIR as a tool to make an qualitative and quantitative analysis and a prediction of the meat and bone meal presence in compound feeds from North Spain cattle farms. Using a global population of compound feeds, on make three different groups depending of MBM percentage presence (0, 0-100, 100), to build and validate one calibration equation to determine MBM content and make one discriminant analysis between these three groups. The preliminary dates obtained with another differents samples of known composition showed promising results.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.3
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• pp.31-36
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• 2017

In this paper, designed infrared (IR) emitter device for infrared scene projector (IRSP) which is used for evaluating the performance of IR sensor systems was simulated by using finite element analysis (FEA) tool and fabricated by using MEMS (Micro Electro-Mechanical System) technology. The performance of the fabricated IR emitter unit device was characterized in the vacuum chamber by using IR image microscope for MWIR($3{\sim}5{\mu}m$), which showed 423K apparent temperature (Tapp) and 22msec time constant (${\tau}$).

• Journal of the Korean Ceramic Society
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• v.21 no.4
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• pp.349-354
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• 1984

The purpose of present study is to find the structure crystallization mechanism and physical properties in $TiO_2$ containing lead zinc borosilicate glass system. The experiments such as differential thermal analysis infrared spectral analysis. X-ray diffraction analysis and thermal expansion measurements have been done. Differential thermal analysis of coarse and fine glass powder showed bulk nucleating mechanism for high $TiO_2$ containing glasses and surface nucleation mechanism for low $TiO_2$ containing glasses. The prepared glasses crystallized to crystalline mixture of PbO.2ZnO. $B_2O_3$ .4PbO.2ZnO.$5B_2O_3$and 2PbO.ZnO.$B_2O_3$ when heat-treated in the range of 480 and 51$0^{\circ}C$ and crystallized to PbTiO3 when heat-treated at $600^{\circ}C$. Obtained crystalline phase of $PbTiO_3$ in glass matrix strongly affects to thermal expansion coefficient and the value of crystallized glass varied 68.0 to $107.1{\times}10-7$/$^{\circ}C$ depending on the amount of $TiO_2$added. Infrared spectral analysis showed that [$BO_3$] triangle and [$BO_3$] tetrahedral units were coexisted in the glass with high content of PbO.

• Korean Journal of Optics and Photonics
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• v.14 no.4
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• pp.369-376
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• 2003

We analyzed the aspheric and/or diffractive surface effects to the performance in the long wavelength infrared (8-12 $\mu$m). Also we investigated the dependence of the NA values for the fixed effective focal length 100 mm when the field angle was varied from 5 degrees to 30 degrees stepped by 5 degrees. We chose the merit function as a criteria to compare the performance of the different lenses. Based on the analysis of the aspheric and/or diffractive surface effects, we designed the optical system of F/l.0 for the uncooled thermal imaging system. As for detector the pixel size was 45 $\mu$m square and the number of pixels were a 320${\times}$240 pixels.

• Asia-Pacific Journal of Atmospheric Sciences
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• v.54 no.4
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• pp.527-544
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• 2018

This paper presents a nighttime sea fog detection algorithm incorporating unsupervised learning technique. The algorithm is based on data sets that combine brightness temperatures from the $3.7{\mu}m$ and $10.8{\mu}m$ channels of the meteorological imager (MI) onboard the Communication, Ocean and Meteorological Satellite (COMS), with sea surface temperature from the Operational Sea Surface Temperature and Sea Ice Analysis (OSTIA). Previous algorithms generally employed threshold values including the brightness temperature difference between the near infrared and infrared. The threshold values were previously determined from climatological analysis or model simulation. Although this method using predetermined thresholds is very simple and effective in detecting low cloud, it has difficulty in distinguishing fog from stratus because they share similar characteristics of particle size and altitude. In order to improve this, the unsupervised learning approach, which allows a more effective interpretation from the insufficient information, has been utilized. The unsupervised learning method employed in this paper is the expectation-maximization (EM) algorithm that is widely used in incomplete data problems. It identifies distinguishing features of the data by organizing and optimizing the data. This allows for the application of optimal threshold values for fog detection by considering the characteristics of a specific domain. The algorithm has been evaluated using the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) vertical profile products, which showed promising results within a local domain with probability of detection (POD) of 0.753 and critical success index (CSI) of 0.477, respectively.

• The Journal of Korean Obstetrics and Gynecology
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• v.29 no.3
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• pp.1-9
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• 2016

Objectives: Cold Hypersensitivity of Hands and Feet (CHHF) has been diagnosed objectively by Digital Infrared Thermal Imaging (DITI) and has been known to be associated with autonomic nervous system (ANS), which can be assessed by Heart Rate Variability (HRV). This study evaluated the correlation between severity of CHHF and HRV variables.Methods: We studied 155 non-menopausal women with CHHF who visited Kyung Hee University Hospital at Gangdong from 01 October 2013 to 30 April 2016. We measured DITI and HRV of each patient. We used DITI to calculate the severity of CHHF with thermal difference between upper arm (L4, 俠白穴) and palm (P8, 勞宮穴) of both hands and anterior thigh (ST32, 伏兎穴) and dorsum of foot (LI3, 太衝穴) of both feet. The correlation between severity of CHHF and HRV variables were analyzed.Results: In time domain analysis, there was significantly positive correlation between the severity of CHHF and both SDNN and RMSSD. In frequency domain analysis, there was significantly positive correlation between the severity of CHHF and TP, HF and HF Norm while there was significantly negative correlation between the severity of CHHF and LF Norm as well as between the severity of cold hypersensitivity of both hands and LF/HF ratio.Conclusions: The more severe CHHF is, the more increased the function of parasympathetic nerve system (PNS) and relatively decreased the function of sympathetic nerve system (SNS) is. Also, it has known that cold hypersensitivity could be caused by deficiency syndrome and qi deficiency has the same ANS tendency as CHHF. Therefore, in practical fields, this result can be helpful in planning treatment and deciding prognosis in respect of deficiency syndrome.

• Journal of the Korea Society for Simulation
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• v.28 no.2
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• pp.139-147
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• 2019

A MANPADS(Man Portable Air Defense System), which tracks infrared energy, is light enough for individuals to carry and can against to a variety of aircraft, making it widely deployed around the world, posing a major threat to aircraft. A flare has been developed as an IRCM(Infrared Countermeasures) that protects the life of friendly aircraft and combatants by deceiving such guided missiles. However, DIRCM, which can overcome the problems of existing IRCM, is being developed mainly in some developed countries, and the need for it has been increasing gradually. This paper modeled first generation IR seeker of AM modulation method, the second generation IR seeker of FM modulation method, and the third generation IR seeker of pulse modulation method among various MANPADS, and modeled the scattering light phenomenon in the seeker when laser beams are investigated in DIRCM. Using this, jamming simulations were performed in various engagement environments of the MANPADS and aircraft equipped with DIRCM, and the miss distance of the guided missiles and aircraft were analyzed. Simulation results show that DIRCM, which irradiates a modulated laser beam with one jamming code, deceives both first, second and third generation MANPADS at 1km and 2km of engagement distance. In particular, the survival rate of aircraft equipped with DIRCM increased when the distance of engagement increased from 1km to 2km, and the survival rate was at least 99% at 2km of engagement distance.