• Journal of the Korean Solar Energy Society
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• v.34 no.3
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• pp.115-121
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• 2014

With increment on interesting about improving renewable energy efficiency, many research have been conducted and the research about hybrid air-water heater using solar energy that can make heating air and hot water has been conducted also. In this experiment, the temperature difference and thermal efficiency were investigated when two heating medium(air and liquid) was working simultaneously. As a result, thermal efficiency showed 44% to 88% when these heating medium was working simultaneously depending on operation condition and it is better than traditional solar collector. Also possibility of application into building equipment also was confirmed based on temperature and thermal efficiency. But necessity of additional studies about proper operation condition according to purpose of use and heat load was confirmed because change of thermal efficiency by air velocity and flux of liquid was shown a huge difference.

• The Journal of Korean Physical Therapy
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• v.31 no.1
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• pp.49-55
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• 2019

Purpose: This study examined the effects of taping therapy on the balance and gait of stroke patients. Methods: The subjects of this study were 30 stroke patients. The treatment groups were prescribed a combination of taping, therapy applied simultaneously to the ankle and the hip joint, and general physical therapy twice a day for 30 minutes each, five days per week for 4 weeks for a total of 40 times. The control group was treated with general physical therapy for 30 minutes, 5 times per week for 4 weeks, and total 40 times. All subjects were followed up on a Berg balance scale, timed up and go test, activity-specific balance confidence scale, and GaitRite. Results: The group that simultaneously received taping therapy to the ankle and hip joint showed more significant effects than the group treated with ankle joint taping only (p<0.05). Effects were noted in the Berg balance scale, timed up and go test, activity-specific balance confidence scale and gait ability test. Compared to the control group, the group treated at the ankle and hip joint showed significant effects after the experiment in the Berg balance scale, timed up and go test, activity-specific balance confidence scale, and gait ability test (p<0.05). Conclusion: Taping therapy applied to both the ankle and hip joints, and combined with general physical therapy appears to be effective in patients with chronic stroke who have an impaired balance and gait ability.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.3
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• pp.318-325
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• 2019

As satellite communication technology with high efficiency and spatiality evolves, demands of customer for efficient and effective satellite broadcasting services are increasing due to interval reduction of the between satellites, and the limited radio-frequency spectrum resources. Recently, research on antenna that it possible to simultaneously receive multiple signal from various satellites while holding maintain the same number of previous reception channels by using the single reflector has been ongoing. It is necessary to be able to simultaneously receive signals from various satellites in order to maintain the same number of previous reception channels. We suggest a multiband antenna which can be simultaneously and independently receiving Ku band and Ka band satellite broadcasting signals transmitted by three adjacent satellites. We have designed and simulated using commercial design tools TICRA CHAMP and CST MWS to meet the target specifications. It appears that the antenna has -10 dB return loss, and more than 40 dBi directivity gain in Ku band and Ka band respectively.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.46.1-46.1
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• 2018

The Fast Imaging Solar Spectrograph (FISS) on the Goode Solar Telescope (GST) at Big Bear Solar Observatory is the imaging Echelle spectrograph developed by the Solar Astronomy Group of Seoul National University and the Solar and Space Weather Group of Korea Astronomy and Space Science Institute. The instrument takes spectral data from a region on the Sun in two spectral bands simultaneously. The imaging is done by the organization of intensity data obtained from the fast raster scan of the slit over the field of view. Since the scan repeats many times, the whole set of data can be used to construct the movies of monochromatic intensity at arbitrary wavelengths within the spectral bands, and those of line-of-sight velocity inferred from different spectral lines. So far there are two standard observing configurations: one recording the $H{\alpha}$ line and the Ca II 8542 line simultaneously, and the other recording the Na I D2 line and Fe I 5435 line simultaneously. We have developed the procedures to produce the standard data for each observing configuration. The procedures include the spatial alignment, the correction of spectral shift of instrumental origin, and the lambdameter measurement of the line wavelength. The standard data include the movie of continuum intensity, the movies of intensity and velocity inferred from a chromospheric spectral line, the movies of intensity and velocity inferred from a photospheric line. The processed standard data will be freely available online (fiss.snu.ac.kr) to be used for research and public outreach. Moreover, the IDL procedures will be provided on request as well so that each researcher can adapt the programs for their own research.

• KIPS Transactions on Computer and Communication Systems
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• v.11 no.10
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• pp.333-344
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• 2022

In a container-based cloud environment, multiple containers can share a graphical processing unit (GPU), and GPU sharing can minimize idle time of GPU resources and improve resource utilization. However, in a cloud environment, GPUs, unlike CPU or memory, cannot logically multiplex computing resources to provide users with some of the resources in an isolated form. In addition, containers occupy GPU resources only when performing GPU operations, and resource usage is also unknown because the timing or size of each container's GPU operations is not known in advance. Containers unrestricted use of GPU resources at any given point in time makes managing resource contention very difficult owing to where multiple containers run GPU tasks simultaneously, and GPU tasks are handled in black box form inside the GPU. In this paper, we propose a container management technique to prevent performance degradation caused by resource competition when multiple containers execute GPU tasks simultaneously. Also, this paper demonstrates the efficiency of container management techniques that analyze and propose the problem of degradation due to resource competition when multiple containers execute GPU tasks simultaneously through experiments.

• Journal of Korean Library and Information Science Society
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• v.54 no.3
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• pp.33-55
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• 2023

There has been research to understand users' information behaviors using book circulation data of public libraries. In this study, we examined the subject areas of books simultaneously borrowed by users of public libraries and aimed to identify the relationships among the subject areas. To accomplish this, we utilized the Korean Decimal Classification codes of 984,790 loaned books in 2019 to transform the lists of concurrently borrowed books, totaling 22,443,699 records, by the same users on the same day, into vectors using the ITEM2VEC technique. Next, we extracted ten highly related classification codes for each classification code, utilizing a total of 522 classification codes to create a network. We identified 15 communities within this network and examined the characteristics of each community. Among the 15 communities, those consisting of two or more main classes allowed us to identify meaningful thematic associations. This study, grounded in users' book usage behaviors, has suggested the topics of books that could be borrowed together. The findings offer valuable insights for library collection development and placement, recommending related subject materials, and revising classification systems.

• Korean Journal of Food Science and Technology
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• v.9 no.3
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• pp.183-189
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• 1977

Studies were made of the continuous production of Pyridoxal 5'-phosphate (pyridoxal-p) on simultaneously immobilized cell column. Whole-cell of Pseudomonas polycolor having high activity of pyridoxine 5'-phosphate (pyridoxine-p) oxidase and Kloeckera sp. No. 2201 having high activity of catalase were used as the enzyme materials. The enzyme sources were entrapped in a polyacrylamide gel. Enzymatic properties of the simultaneously immobilized cells were investigated, comparing with those of the mixed whole-cells of the microorganisms. The simultaneously immobilized cells had higher enzyme activity than singly immobilized cells of Pseudomonas polycolor. From this result, the simultaneously immobilized pyridoxine-p oxidase-catalase system could be available to exert a protective effect upon the pyridoxine-p oxidase by destroying $H_2O_2$ which is a by-product of pyridoxine-p oxidation. The optimum pH was 9.0 for the immobilized cells and the whole-cells. The optimum temperature was $45^{\circ}C$ for the immobilized cells and $40^{\circ}C$ for the whole-cells. The pyridoxine-p oxidase of the immobilized cells were activated by $Hg^{++}$ and some SH-compounds.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2010.10a
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• pp.401-402
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• 2010

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1031-1032
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• 2013

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.146-149
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• 1998

In this study, the chloride ion penetration test and the compressive strength test should be done simultaneously on the standard cylinder specimen. And from analyzing the data from those tests, a strength estimation equation with high credibility is to be developed.