• Journal of Broadcast Engineering
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• v.20 no.2
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• pp.204-214
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• 2015

Depth map upsampling is an approach to increase the spatial resolution of depth maps obtained from a depth camera. Depth map quality is closely related to 3D perception of stereoscopic image, multi-view image and holography. In general, the performance of upsampled depth map is evaluated by PSNR (Peak Signal to Noise Ratio). On the other hand, time-consuming 3D subjective tests requiring human subjects are carried out for examining the 3D perception as well as visual fatigue for 3D contents. Therefore, if an objective metric is closely correlated with a subjective test, the latter can be replaced by the objective metric. For this, this paper proposes a best metric by investigating the relationship between diverse objective metrics and 3D subjective tests. Diverse reference and no-reference metrics are adopted to evaluate the performance of upsampled depth maps. The subjective test is performed based on DSCQS test. From the utilization and analysis of three kinds of correlations, we validated that SSIM and Edge-PSNR can replace the subjective test.

• Korean Chemical Engineering Research
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• v.49 no.3
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• pp.325-329
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• 2011

$Ir(pmb)_{3}$(Iridium(III)Tri(1-phenyl-3-methylbenzimidazolin-2-ylidene-$C,C^{2'}$ ) was synthesized to develop a deep blue-emitting Ir(III) complex. We suggested the ultrasonic reactor to enhance the poor reaction yield of $Ir(pmb)_{3}$. The ultrasonic wave enhanced the reaction yield of $Ir(pmb)_{3}$ because the ultrasound helped non-soluble reactants disperse efficiently and produced free radial during the reaction. The maximum yield of $Ir(pmb)_{3}$ was 42.5%, which was 4 times higher than conventional method. Organic light emitting devices were fabricated with the synthesized mer-$Ir(pmb)_{3}$ which emitted at 405 nm. A range of host materials with large bandgaps (UGH2, mCP and CBP) were tested for developing a deep blue emitting device. In case of the device with mCP as the host material, it emitted deep blue and performed quite well relative to the other host materials tested.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39B no.11
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• pp.779-789
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• 2014

Cognitive radio (CR) technology based on geo-location database access approach and/or wideband spectrum sensing approach is absolutely vital in order to recognize available frequency bands in white spaces (WSs), and efficiently utilize shared spectrums. This paper presents a new structure for the TVWS database access protocol implementation based on Internet Engineering Task Force (IETF) Protocol to Access WS database (PAWS). A wideband compressive spectrum sensing (WCSS) scheme using a modulated wideband converter is also proposed for the TVWS utilization. The developed database access protocol technology which is adopted in both the TV band device (TVBD) and the TVWS database operates well in the TV frequency bands. The proposed WCSS shows a stable performance in false alarm probability irrespective of noise variance estimation error as well as provides signal detection probabilities greater than 95%. This paper also investigates Federal Communications Commision (FCC) regulatory requirements of TVWS database as well as European Telecommunications Standards Institute (ETSI) policy related to TVWS database. A standardized protocol to achieve interoperability among multiple TVBDs and TVWS databases, which is currently prepared in the IETF, is discussed.

• Journal of the Korean Applied Science and Technology
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• v.32 no.2
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• pp.330-338
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• 2015

The influences of fluorescence, scattering, and flocculation in turbid material by light scattering of N-propyl-N,N-dimethylethanolamine, fluorescence agent and absorption agent were interpreted for the scattered fluorescence intensity and wavelength. They have been studied the molecular properties by the spectroscopy of laser induced fluorescence (LIF) and flocculation. The effects of optical properties in scattering media have been found by the optical parameters(${\mu}_s$, ${\mu}_a$, ${\mu}_t$). Flocculation is an important step in many solid-liquid separation processes and is widely used. When two particles approach each other, interactions of several colloid particles can come into play which may have major effect on the flocculation and LIF process. The values of scattering coefficient ${\mu}_s$ are large by means of the increasing scattering of scatterer, The values have been found that the slope decays exponentially as a function of concentration from laser source to detector by our experimental result. It may also aid in designing the best model for oil chemistry, bio-pharmaceutical, laser medicine and application of medical engineering on LIF and coagulation in particle transport mode.

• Korean Security Journal
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• no.48
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• pp.35-56
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• 2016

The purpose of this study is to find the development of the special security business plan based on the problem that guards are now aware of special security service. In order to achieve the objectives of this study, we analyzed the data after expert survey and interview conducted by seven experts engaged in special security services more than 10 years. The guard who perform special security service proposed a development plan of special security services as follows. First, the current education system for new employees' training is required to improve the educational program of 60 hours in subjects related to special security duties by reorganization. Second, the special security service training for guards also appropriate to switch to 9-hour training program for three months through an educational organization controlled by country. Third, the special security guards should be proceeding the practical programs required in the field and quality education in the different section by competent and professional instructors. Fourth, the retirement age for special security guard stipulated in the Security Services Industry Act that needs to be readjusted upward by considering the social environment. Sixth, there needs to be organized the Special Security Association for development associated with the special security service and to protect the rights of special security guards.

• Journal of The Korean Association For Science Education
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• v.37 no.1
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• pp.181-192
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• 2017

This study aims to examine the educational effects of the SSI program using Digital Storytelling (DST) approaches. Since DST provides students opportunities to express their own opinions in the form of stories and to share learning outcomes through the web, we developed and implemented SSI program by adopting the concept of DST in order to produce synergistic effects on student learning. Twenty-four 9th graders who enthusiastically engaged in the DST-based SSI program participated in this study. The students responded to focus group interviews after the instruction, and all interviews were transcribed for analysis. The results indicated that the students became aware of socio-ethical perspectives of each SSI topic while searching and collecting data by themselves. They also felt the necessity to consider multiple perspectives around the issues by having discussions with group members. Second, pre-producing DST allowed students to negotiate to settle on a group discussion, and to use emotional contents that can lead viewers to have sympathy. In addition, while producing DST, students considered various factors such as design, soundtrack, visual effects, and screen composition in order to express their opinions and convey their messages more effectively. In the stage of sharing DST outcomes and receiving feedback, they realized new perspectives that they did not perceive in the previous production process, and to move them into an action for resolving the problems caused by SSI. This study showed the potentials of DST-based SSI instruction as a good strategy to support students' SSI engagement.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.11
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• pp.1653-1660
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• 2016

The synthetic aperture rardar (SAR) is an active sensor using microwaves. It transmits a microwave signal, called a chirp pulse, and receives the reflected signal in a moving platform such as satellite and unmanned aerial vehicle. Since this sensor uses microwaves that can penetrate the atmosphere, SAR generates the images regardless of light and weather conditions. However SAR operates on the moving platform, the Doppler shift and the side-looking observation method should be considered. In addtion, a residual image or ghost image can be occurred according to selection of the pulse repetition frequency (PRF). In this paper, a range design of the PRF for the L-band spaceborne SAR system is studied for prevention of SAR image distortion. And the system is studied for prevention of SAR image distortion. And the system parameter and the PRF are calibrated iteratively according to the proposed system design procedure and design constraints. The MATLAB based on SAR system simulator has been developed to verify the validity of calculated PRF. The developed simulator assumes that SAR sensor is operated by the PRF calculated from the design. The results of the simulator show that the targets in image has a valid peak to side-lobe ratio (PSLR) so that the PRF can be used for the spaceborne SAR sensor.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.42 no.4
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• pp.337-342
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• 2016

Melasma has several well-recognized etiologic factors, but most researches focus on melanogenesis. The purpose of this study is to show improvement of melasma by reducing vascularity distinguished from melanogenesis. We examined 20 Korean women with both melasma and solar lentigo that were visually assessed by a dermatologist. The volunteers applied functional cosmetics for 8 weeks. We analyzed the results obtained using the chromameter, evaluating the skin color of three areas (melasma lesions, solar lentigo lesions, and non-lesional skin) on the face of volunteer. There was a statistically significant improvement in the brightness and redness of melasma lesions compared to those of non-lesional skin after 8 weeks. Also, we observed that the improvements in the brightness of melasma lesions and solar lentigo lesions were similar. However, the redness of melasma lesions improved more than that of solar lentigo lesions with statistical significance after 8 weeks. In this study, we have shown that brightness and redness in melasma lesions can be improved by functional cosmetics. Thus, we suggest redness to be an additional suitable parameter for the evaluation of melasma lesions.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.6
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• pp.245-251
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• 2015

We have applied mechanical alloying (MA) to produce soft magnetic composite material using a mixture of elemental $Fe_2O_3$-Mg powders. An optimal milling and heat treatment conditions to obtain soft magnetic ${\alpha}$-Fe/MgO composite with fine microstructure were investigated by X-ray diffraction, differential scanning calorimetry (DSC) and vibrating sample magnetometer (VSM) measurement. It is found that ${\alpha}$-Fe/MgO composite powders in which MgO is dispersed in ${\alpha}$-Fe matrix are obtained by MA of $Fe_2O_3$ with Mg for 30 min. The saturation magnetization of ball-milled powders increases with increasing milling time and reaches to a maximum value of 69.5 emu/g after 5 h MA. The magnetic hardening due to the reduction of the ${\alpha}$-Fe grain size by MA was also observed. Densification of the MA powders was performed in a spark plasma sintering (SPS) machine at $800{\sim}1000^{\circ}C$ under 60 MPa. X-ray diffraction result shows that the average grain size of ${\alpha}$-Fe in ${\alpha}$-Fe/MgO nanocomposite sintered at $800^{\circ}C$ is in the range of 110 nm.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.13 no.3
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• pp.211-218
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• 2015

The reaction rates of ZIRLO cladding hulls with cross-section openings were investigated using a thermo-gravimetric analysis system in order to identify whether selective recovery of Zr from oxidized cladding hulls is possible. The experimental results showed that an oxidized ZIRLO cladding hull was not reactive with chlorine gas at 400℃. However, providing fresh cross-sections on one or both ends of the ZIRLO hulls enabled a chlorination reaction. This reaction was completed after 8 hours; a 14% increase on the 7 hours seen with a bare ZIRLO cladding hull. The Sharp-Hancock plot analysis results revealed that the contracting volume model is the best for describing the reaction between the cross-section opened ZIRLO hulls and chlorine gas under the condition of this work. It was concluded that the chlorination process can be employed for oxidized ZIRLO cladding hulls by providing cross-section openings.