• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.559-563
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• 2015

Monitor of All-sky X-ray Image (MAXI) is a Japanese X-ray all-sky surveyer mounted on the International Space Station (ISS). It has been scanning the whole sky since 2009 during every 92-minute ISS rotation. X-ray transients are quickly found by the real-time nova-search program. As a result, MAXI has issued 133 Astronomer's Telegrams and 44 Gamma-ray burst Coordinated Networks so far. MAXI has discovered six new black holes (BH) in 4.5 years. Long-term behaviors of the MAXI BHs can be classified into two types by their outbursts; a fast-rise exponential-decay type and a fast-rise flat-top one. The slit camera is suitable for accumulating data over a long time. MAXI issued a 37-month catalog containing 500 sources above a ~0.6 mCrab detection limit at 4-10 keV in the region ${\mid}{b}{\mid}$ > $10^{\circ}$. The SSC instrument utilizing an X-ray CCD has detected diffuse soft X-rays extending over a large solid angle, such as the Cygnus super bubble. MAXI/SSC has also detcted a Ne emission line from the rapid soft X-ray nova MAXI J0158-744. The overall shapes of outbursts in Be X-ray binaries (BeXRB) are precisely observed with MAXI/GSC. BeXRB have two kinds of outbursts, a normal outburst and a giant one. The peak dates of the subsequent giant outbursts of A0535+26 repeated with a different period than the orbital one. The Be stellar disk is considered to either have a precession motion or a distorted shape. The long-term behaviors of low-mass X-ray binaries (LMXB) containing weakly magnetized neutron stars are investigated. Transient LMXBs (Aql X-1 and 4U 1608-52) repeated outbursts every 200-1000 days, which is understood by the limit-cycle of hydrogen ionization states in the outer accretion disk. A third state (very dim state) in Aql X-1 and 4U 1608-52 was interpreted as the propeller effect in the unified picture of LMXB. Cir X-1 is a peculiar source in the sense that its long-term behavior is not like typical LMXBs. The luminosity sometimes decreases suddenly at periastron. It might be explained by the stripping of the outer accretion disk by a clumpy stellar wind. MAXI observed 64 large flares from 22 active stars (RS CVns, dMe stars, Argol types, young stellar objects) over 4 years. The total energies are $10^{34}-10^{36}$ erg $s^{-1}$. Since MAXI can measure the spectrum (temperature and emission measure), we can estimate the size of the plasma and the magnetic fields. The size sometimes exceeds the size of the star. The magnetic field is in the range of 10-100 gauss, which is a typical value for solar flares.

• Korean Journal of Optics and Photonics
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• v.14 no.2
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• pp.142-145
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• 2003

The nonreciprocal phase shift characteristics of infinite slab optical waveguides with magneto-optic materials in the cladding layer was calculated at 1.55 ${\mu}{\textrm}{m}$ for optical isolators. The infinite slab waveguide structures considered in this paper were as follows. rho magneto-optic materials used as a cladding layer were Ce:YIG and LNB(LuNdBi)$_3$(FeAl)$_{5}$)$_{12}$,). Their specific Faraday rotations Θ$_{F}$ are 4500$^{\circ}$/cm, 500$^{\circ}$/cm at wavelength 1.55 ${\mu}{\textrm}{m}$ respectively. The guiding layer with multi-quantum well structure was used, and it consists of 1.3Q and InGaAs. In order to investigate the effect of evanescent field penetrating the cadding, layer, guiding mode characteristics were calculated for the cases when the substrate is InP and air. We calculated the minimum lengths of 90$^{\circ}$ nonreciprocal phase shifters and their optimum guiding layer thicknesses in various optical waveguide structures.res.s.

• Journal of the Korea Convergence Society
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• v.11 no.9
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• pp.297-303
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• 2020

The purpose of this study is to investigate the effects of aerobic exercise and probiotics ingestion on motor learning and body weight in female mice during adolescence. The subjects were divided into six groups of variables, such as non-exercise, moderate, high-intensity exercise, probiotics ingestion, and non-probiotics, and then treated for four weeks. The vertical grid test was conducted before and after the treatment to evaluate motor learning and bodyweight. The high-intensity exercise and probiotics ingestion group showed fastest up, rotation, and down rate than the non-exercise group (p<.001). Also, a group that treated exercise and probiotics tended to record speedier performance than those that performed the only exercise. Comparing weight changes, the weight gain of a group that performed only moderate-intensity exercise was higher than that of a non-probiotics and non-exercise group (p=.032). Taken together, aerobic exercise during adolescence can help improve motor learning, and more efficient motor learning can be achieved when combined with probiotics ingestion.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.3
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• pp.275-282
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• 2009

Generally, the sinusoidal cavity dither is adopted to ring laser gyroscope for eliminating the lock-in which is non-linear effect at the small rotation input. Despite this method, there are some remained errors which are generated at the dither turnaround, and those errors produce random walk which is a general character of a ring laser gyroscope. As one of the numerous research results for compensating these errors, there is a special lock-in compensation method which is the method of error estimation and compensation by comparing the beat signal periods of before and after the dither turnarounds. In this paper, by ring laser gyroscope modeling and numerical analysis, we verified the theoretical validity and confirmed the effectiveness of this method in expectation of the possible beat signal measurement time resolution. As a result, we confirmed the random walk decreases from a-half to a-third by this lock-in compensation method. So, it is expected to be a remarkable method for reducing the INS alignment time.

• Journal of the Korean Wood Science and Technology
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• v.42 no.3
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• pp.282-289
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• 2014

After being laminated with a combination of glass fiber reinforced plastic and plywood, the GFRP laminated plate was densificated for 1 hour at $150^{\circ}C$ with pressure of $1.96N/mm^2$. A partial reinforced beam was produced by attaching the 5 GFRP laminated plates to the joint of glulam and the column. In addition, the column to beam joint was produced by using reinforced laminated wooden pin which was made of GFRP sheet and plywood, fiber glass reinforced cylindrical-LVL column. The joint was made of round log, glulam and drift pin as the reference specimen, and its moment resistance was evaluated. As a result, the strength performance of specimens with partial reinforced beams were 1.8 times stronger than the reference specimen on average. Furthermore, rupture was neither occurred on partial reinforced beam nor column. Toughness and stiffness of joints were also fine. The GFRP sheet reinforced laminated plate showed better reinforcement effect than GFRP textile reinforced one. GFRP sheet was inserted into each layer of laminate, and it showed good condition in rotation-angle and strength, therefore it is the most appropriate to reinforce the part of the beam.

• Journal of Plant Biotechnology
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• v.47 no.1
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• pp.66-72
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• 2020

Alstroemeria plants were transformed by using an improved particle-gun-mediated transformation system. Friable embryogenic callus (FEC) induced from the leaves with axil tissues of Alstroemeria plant was used as the target tissue. Also, FEC was transformed with the bar gene was used as a selectable marker. In the case of plasmid pAHC25, 7.5% of the twice-bombarded FEC clumps showed blue foci, whereas the clumps with single bombardment showed only 2.3%. Additionally, a 90° rotation with double bombardment led to a higher frequency (6 times) of luciferase gene expression in PBL9780 than the control treatment. After 8 weeks of bombardment, more than 60 independent transgenic lines were obtained for pAHC25 and nearly 150 independent transgenic lines were obtained for PBL9780, all of which were resistant to PPT and demonstrated either GUS or luciferase activity. Regarding effect of osmotic treatment (0.2 M mannitol) with 7 different periods, the highest transient gene expression was obtained in 8 h before and 16 h after transformation in both pAHC25 and PBL9780. Compared with the control, at least three times more GUS foci and photons were observed in this treatment. With respect to different combinations of mannitol and sorbitol with 8 h before and 16 h after transformation, high numbers of transient and stable transgene expressions were observed in both 0.2 M mannitol and 0.2 M sorbitol used in the osmotic pre-culture. This combination showed the highest transformation efficiency in both pAHC25 (8.5%) and PBL9780 (14.5%). In the control treatment, only 10% of the FEC clumps produced somatic embryos. However, by using 0.2 M mannitol and 0.2 M sorbitol, the frequency of somatic embryos increased to 36.5% (pAHC25) and 22.9% (PBL9780). Of the somatic embryos produced, at least 60% germinated. Approximately 100 somatic embryos from these 210 independent transgenic lines from 2 plasmids developed into shoots, which were then transferred to the greenhouse. PCR analysis confirmed the presence of the bar gene. This is the report on the production of transgenic Alstroemeria plants by using particle bombardment with a high efficiency, thereby providing a new alternative for the transferring of gene of interests in Alstroemeria in the breeding program in the future.

• Journal of vocational education research
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• v.37 no.1
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• pp.31-53
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• 2018

Uncertainty of career environment driven by globalization and shift of employment context drives heavy competition of labor market and anxiety of employment for individuals. New career paradigm based on this environmental change puts emphasis on subjective career success from individual's viewpoint as important career outcome and individual's proactive career development efforts. In addition to this, importance of person-environment fit and person-job fit is growing in relationship between career planning and career success. Based on this perspective, this study aims to identify whether person-environment fit and person-job fit mediate the relationship between career development and subjective career success. Data analysis of questionnaire from 220 employees showed that both fits mediate the relationship. This result implies that individual's proactive career planning is critical to career success and this strengthens one's satisfaction to organization and job. To organization, strategies need to be developed to design career development of employees' based on their career needs and organizational intervention such as job-rotation system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.407-416
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• 2019

This study is about a Customized Nursery School where working women can support work - life balance and a reduction in retirement or turnover. The research method is to identify the current status of Customized Nursery services and to recognize the recognition and need of the operation of Customized Nursery School. The importance of securing skilled nurses and preventing them from changing their jobs for the health and safety of people cannot be emphasized enough. A Customized Nursery School must be opened to reduce the retirement or change of jobs of working women nurses and to provide care for continuous work in three shifts from 365days to support the balance between the working mother and family. It is considered that nurses will put their children in relief when using retired nurses who have the ability to work 24hour rotation in a Customized Nursery School and when a Customized Nursery School be ran suited for the condition and demand of working women nurses, it is expected to reduce retirement and the change of jobs, also to give positive effect on marrige and family planning which would make improvement in low birthrate. To activate the Customized Nursery School, Creating a secure learning environment and qualification of educators great effort should be put. A program curriculum based on 'basic life and habits' should be the center of education. Continuous management and effort will need to be placed in continuous development of educators.

• (The) Research of the performance art and culture
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• no.25
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• pp.91-134
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• 2012

This study is to prove out that the group members' prejudice about divorce was lessened by participating in the sociodrama, making the sociodrama performed during five sessions from September 27, 2011 to November 8, 2011 as object of study. The prejudice was lessened mainly by way of role rotation, which was interpreted on the philosophical basis, '~becoming' of Gilles Deleuze, $F{\acute{e}}lix$ Guattari. The results of this study are as follows. Firstly, the lessening of prejudice about divorce was realized by way of 'true meeting'. It is achieved by the boundary-blurring between 'You' and 'I' through the 'molecular-becoming'. Secondly, the participants took a stricter stance against the divorce by a extramarital affair rather than the divorce by a domestic violence. It is thought that the boundary-blurring in the divorce by a extramarital affair is able to be accomplished more effectively than the boundary-blurring in domestic violence. Fourthly, an understanding of society not as an individual, 'I' but as a community, 'We' worked effectively in solving various social problems. This perspective is helpful in blurring the boundary between 'You' and 'I', and then in seeing 'You' and 'I' as a whole entity. In conclusion, it is found out that this sociodrama program has a considerable effect on the lessening of the prejudice about divorce.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.2
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• pp.133-142
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• 2022

The purpose of this study is to develop an impact crusher with a radial rotating plate installed at the bottom, which is a shock absorber that can produce high-quality recycled coarse aggregate for concrete and to verify the effect of improving the quality performance of recycled coarse aggregate and its applicability through concrete tests. As a result, it showed improved quality in all items such as absolute dry density, absorption rate, abrasion resistance, Particle shape judgment rate, amount lost in the 0.08 mm sieve passing test, alkali aggregate reaction, clay mass, stability, and impurity content, and it was found to meet the criteria of recycled aggregate quality standards. In addition, the air volume and slump of concrete to which recycled coarse aggregate is applied meet all domestic standards. According to the test results of the compressive strength characteristics by age of concrete according to the mixing ratio of the recycled coarse aggregate, it was confirmed that the mixing ratio of the recycled coarse aggregate was applicable up to 60 %.