• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.49.3-49.3
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• 2021

The 76 cm telescope in Kyung Hee Astronomical Observatory is participating in the small telescope network of the SomangNet project, which started in 2020. Since the installation of the telescope in 1992, the system configuration has been changed several times. The optical system of this telescope has a Ritchey-Chrétien configuration with 76 cm in diameter and the focal ratio is f/7. The mount is a single fork equatorial type and its control system is operated by TheSkyX software. We use a science camera with a 4k × 4k CCD and standard Johnson-Cousins UBVRI filters, which cover a field of view of 23.7 × 23.7 arcmin. We are also developing the Kyung Hee Automatic Observing Software for the 76 cm telescope (KAOS76) for efficient operations. In this work, we present the standard star calibration results, the current status of the system, and the expected science capabilities.

• Journal of Photoscience
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• v.9 no.2
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• pp.267-268
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• 2002

A vertebrate retina is an organ belonging to the central nerve system (CNS), and is usually difficult to regenerate except at an embryonic stage in life. However, certain species of urodele amphibians, such as newts and salamanders, possess the ability to regenerate a functional retina from retinal pigment epithelial (RPE) cells even as adults. After surgical removal of neural retinas from adult newt eyes, the remaining RPE cells lose their pigment granules, transdifferentiate into retinal progenitor cells, which further differentiate into various retinal neurons, and then finally reform a functional neural network. To understand the molecular mechanisms of CNS regeneration, we attempted to investigate the genes expressing in regenerating newt retina. mRNAs were isolated from regenerating retinas at 18-19 days after the surgical removal of the normal retina, and a cDNA library (regenerating retinal cDNA library) were constructed. Our EST analysis of 112 clones in the regenerating cDNA library revealed that about 70% clones are closely related to the genes previously identified. About 40% clones are housekeeping genes, and about 15% clones encode proteins related to the regulation of gene expression and to the proliferation of the cells. Sequences similar to neural retina- and RPE-specific genes were not detected at all. These results led us to suppose that the regenerating retinal cells are in a state considerably different from those of neither neural retina nor RPE cells.

• Journal of the Optical Society of Korea
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• v.16 no.2
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• pp.141-144
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• 2012

A mobile Rayleigh Doppler wind LIDAR at an eye-safe wavelength of 355 nm incorporating double-edge technique with triple-channel Fabry-Perot etalon is developed for wind measurement from 5 to 40km. The structure of this LIDAR system is described. An intercomparsion experiment with rawinsonde is made, showing good agreement with expected measurement accuracy. A continuous observation of stratosphere wind field for several days with temporal resolution of 15 min and spatial resolution of 200 m from 5 to 40 km is presented, demonstrating the stability and robustness of the LIDAR. A stratospheric quasi-zero wind layer can be found at around 20 km with a direction change from east to west evident in the continuous observation.

• BMB Reports
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• v.48 no.10
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• pp.583-588
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• 2015

Microtubule actin crosslinking factor 1 (MACF1), a widely expressed cytoskeletal linker, plays important roles in various cells by regulating cytoskeleton dynamics. However, its role in osteoblastic cells is not well understood. Based on our previous findings that the association of MACF1 with F-actin and microtubules in osteoblast-like cells was altered under magnetic force conditions, here, by adopting a stable MACF1-knockdown MC3T3-E1 osteoblastic cell line, we found that MACF1 knockdown induced large cells with a binuclear/multinuclear structure. Further, immunofluorescence staining showed disorganization of F-actin and microtubules in MACF1-knockdown cells. Cell counting revealed significant decrease of cell proliferation and cell cycle analysis showed an S phase cell cycle arrest in MACF1-knockdown cells. Moreover and interestingly, MACF1 knockdown showed a potential effect on cellular MTT reduction activity and mitochondrial content, suggesting an impact on cellular metabolic activity. These results together indicate an important role of MACF1 in regulating osteoblastic cell morphology and function.

• Imaging Science in Dentistry
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• v.47 no.3
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• pp.199-207
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• 2017

Purpose: Evaluation of alveolar bone is important in the diagnosis of dental diseases. The periodontal ligament space is difficult to clearly depict in cone-beam computed tomography images because the reconstruction filter conditions during image processing cause image blurring, resulting in decreased spatial resolution. We examined different reconstruction filters to assess their ability to improve spatial resolution and allow for a clearer visualization of the periodontal ligament space. Materials and Methods: Cone-beam computed tomography projections of 2 skull phantoms were reconstructed using 6 reconstruction conditions and then compared using the Thurstone paired comparison method. Physical evaluations, including the modulation transfer function and the Wiener spectrum, as well as an assessment of space visibility, were undertaken using experimental phantoms. Results: Image reconstruction using a modified Shepp-Logan filter resulted in better sensory, physical, and quantitative evaluations. The reconstruction conditions substantially improved the spatial resolution and visualization of the periodontal ligament space. The difference in sensitivity was obtained by altering the reconstruction filter. Conclusion: Modifying the characteristics of a reconstruction filter can generate significant improvement in assessments of the periodontal ligament space. A high-frequency enhancement filter improves the visualization of thin structures and will be useful when accurate assessment of the periodontal ligament space is necessary.

• Journal of the Korean Institute of Educational Facilities
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• v.28 no.6
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• pp.3-13
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• 2021

Introduced in 2004 as an 'After-School Academy' policy, the 'After-School Care Class' has become a universal program for elementary schools over time. While the concept of public education service has expanded and changed in various ways including educational welfare, the physical environment of the care classroom has undergone fixed changes within the uniform classroom structure of a standardized school space. The purpose of this study is to identify spatial characteristics of care classroom through chasing and analysing changes in the care class space configuration from 2004 to the present. The findings are as follows. The plan of the early care classroom wasn't much different from the existing common classroom, and it was only in 2007 that the kitchen and floor heating appeared for the first time.From the 2015 standard plan, prominent differentiation of the space between learning activities and resting area was shown, but the spatial characteristics are nothing more than a division that utilizes ready-made furniture. A distinctive feature of the 2018 Seoul care classes are diversity. In the case of the care exclusive classrooms, the division between the support space and the main activity space became more clear using furniture integrated open walls and various floor levels. In the case of a shift classrooms that is used together with common classrooms, it is characterized by flexibility that allows dramatically different classroom configurations for each time period by using a convertible furnishing space.

• Journal of Astronomy and Space Sciences
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• v.29 no.1
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• pp.23-31
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• 2012

Thermal analysis and control design are prerequisite essential to design the satellite. In the space environment, it makes satellite survive from extreme hot and cold conditions. In recent years CubeSat mission is developed for many kinds of purpose. Triplet Ionospheric Observatory (TRIO)-CubeSat for Ion, Neutral, Electron, MAgnetic fields (CINEMA) is required to weigh less than 3 kg and operate on minimal 3 W power. In this paper we describe the thermal analysis and control design for TRIO-CINEMA mission. For this thermal analysis, we made a thermal model of the CubeSat with finite element method and NX6.0 TMG software is used to simulate this analysis model. Based on this result, passive thermal control method has been applied to thermal design of CINEMA. In order to get the better conduction between solar panel and chassis, we choose aluminum 6061-T6 for the material property of standoff. We can increase the average temperature of top and bottom solar panels from $-70^{\circ}C$ to $-40^{\circ}C $ and decrease the average temperature of the magnetometer from $+93^{\circ}C$ to $-4^{\circ}C$ using black paint on the surface of the chassis, inside of top & bottom solar panels, and magnetometer.

• The Bulletin of The Korean Astronomical Society
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• v.26 no.1
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• pp.56-56
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• 2001

• The Bulletin of The Korean Astronomical Society
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• v.34 no.1
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• pp.80.2-80.2
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• 2009

• The Journal of Sustainable Design and Educational Environment Research
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• v.11 no.2
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• pp.1-8
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• 2012

Due to the fact that there are low birth rate and longer life longevity, schools have been shutting down and converted into welfare facilities. However, most of researches about utilizing closed down school are focused on case researches or architectural planning and design. Moreover, majority of existing welfare centers for the aged are not designed with the flow of human traffic in mind, which means there is no consideration of physical or psychological characteristics of elderly people. That fact leads to increasing number of shutting down welfare facilities. Therefore, this thesis will present the necessity of effective space allocation, extension and reconstruction for residents in aged care by analyzing space using index of space syntax with depth-map software.