• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.47.3-47.3
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• 2021

In this talk I will review recent progress that the SDSS-IV / eBOSS collaboration has made in constraining cosmology from the clustering of galaxies, quasars and the Lyman-alpha forest. The SDSS-IV / eBOSS collaboration has measured the baryon acoustic oscillation (BAO) and redshift space distortion (RSD) features in the correlation function in redshift bins from z~0.15 to z~2.33. These features constitute measurements of angular diameter distances, Hubble distances, and growth rate measurements. A number of consistency tests have been performed between the BAO and RSD datasets and additional cosmological datasets such as the Planck cosmic microwave background constraints, the Pantheon Type Ia supernova compilation, and the weak lensing results from the Dark Energy Survey. Taken together, these joint constraints all point to a broad consistency with the standard model of cosmology LCDM + GR, though they remain in tension with local measurements of the Hubble parameter.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.765-769
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• 2009

The Augmented Reality of existing for the interaction which the object and background is smooth used the data glove or marker. It is inconvenient to a use and it occurs the result of immersion feeling decrease. Immersion it will wind from Augmented Reality and the hazard which it strengthens the removal of the additional entry device which stands is necessary. It recognizes the space coordinates which is accurate even from the condition where the hazard marker which will reach does not attach in necessity. Immersion feeling improvement from Augmented Reality wearing the hazard additional entry device it proposes the space coordinate creation technique of the virtuality description below for a interaction without from the present paper. The method which is proposed the image which it acquires the object of virtuality reflected at 2D space and the characteristic line about under extracting the space coordinate which reflects about under calculating it reflected. The application is possible in markerless Augmented Reality and the mobile Augmented Reality.

• Journal of the Korean Society of Safety
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• v.34 no.3
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• pp.96-101
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• 2019

Chemicals Control Act have been strengthened to control more safely hazardous chemicals from 2015. In particular, the standards for the installation and management of handling facilities was enhanced with specific regulations depending on type of the facilities and the hazardous chemicals. However, some standards for handling facilities caused difficulties in implementing the strengthened standards due to various field conditions, such as lack of physical space. The Ministry of Environment is implementing Safety Assessment System (SAS) to solve these problems since 2018. However, many plants have difficulties in preparing alternative methods to pass the safety evaluation. The purpose of this study was to review and analyze the SAS and to suggest alternative measures in terms of management and technical aspects through the case study of hydrochloric acid storage tanks. The following safety solutions were suggested for handling facilities that had insufficient the space and capacity for the retaining wall due to physical space. Firstly, insufficient space was resolved by introducing equipment relocation or demolition, and retaining wall expansion. Secondly, the wall of the surrounding buildings was used as an alternative to the retaining wall with additional chemical resistant treatment. Finally, sensor installation and facility inspection were suggested as ways to improve chemical safety. Therefore, improvement of chemical accident prevention system is required not only in terms of facilities supplementation but also management aspect. The results of this study are expected to be available for similar facilities and will be based on the preparation of additional safety assessment as alternatives measures in the future.

• Journal of Korean Society of Archives and Records Management
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• v.15 no.2
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• pp.83-101
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• 2015

This study aims to examine the capability of organizing local records. Based on literature reviews, this study identified that space can be a useful context of records. Accordingly, it designed a records model on additional space entity. It attempted to organize five sample records based on the space of the port of Busan (Busanhang) using CIDOC CRM (6.0). In conclusion, it presented that a space entity provides relations across other entities. As such, it is possible to propose a defining space entity when designing records model that can support the understanding of records' contexts.

• ETRI Journal
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• v.17 no.4
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• pp.25-35
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• 1996

This paper derives the symbol error probability for quadrature amplitude modulation(QAM) with L-fold space diversity in Rayleigh fading channels. Two combining techniques, maximal ratio combining(MRC) and selection combining(SC), are considered. The formula for MRC space diversity is obtained by averaging the symbol error probability of M-ary QAM in an additive white Gaussian noise(AWGN) channel over a chi-square distribution with 2L degrees of freedom. The obtained formula overcomes the limitations of the earlier work, which has been limited only to deriving the symbol error rate(SER) of QAM with two branch MRC space diversity. The formula for SC space diversity is obtained by averaging the symbol error probability of M-ary QAM in an AWGN channel over the distribution of the maximum signal-to noise ratio among all of the diversity channels for SC space diversity has been reported yet. Analytical results show that the probability of error decreases with the order of diversity gain per additional branch decreases as the number of branches becomes larger. On the other hand, the performance of 16 QAM with MRC becomes much better than that of SC as the number of branches becomes larger. By giving the order of diversity, L, and the number of signal points, M, we have been able to obtain the SER performance of QAM with general space diversity. These results can be used to determine the order of diversity to achieve the desired SER in land mobile communication system employing QAM modulation.

• Journal of Practical Agriculture & Fisheries Research
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• v.15 no.1
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• pp.107-121
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• 2013

This study was developed to investigate the effects of privately owned public space (POPS) on urban streetscape and to find ways to prevent the discontinuation of street continuity on urban landscape when creating POPS in urban space and the surrounding streets. Several case studies and policies and laws related to POPS were reviewed to identify the practical problems as well as current state. An additional analysis was conducted on the different types of POPS to examine spatial connections between them and streetscapes and to find ways to improve POPS on urban streetscape. Our results show that POPS surrounding a building (i.e. frontage space and adjacent sidewalks) should be considered as one space in the integrated perspective. In addition, the type of facilities installed on POPS would be decided according to whether POPS is recognized as the part of public rest area or treated as the part of street. The results of the study will serve as useful data to solve the current problems with city's POPS, which destroys spatial continuity by focusing on increasing the number of POPS and creates high-rise buildings isolated from existing spaces. This study will also contribute to improve the quality of future POPS.

• Bulletin of the Korean Mathematical Society
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• v.53 no.5
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• pp.1471-1481
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• 2016

We characterize reducing subspaces of weighted shifts with operator weights as wandering invariant subspaces of the shifts with additional structures. We show how some earlier results on reducing subspaces of powers of weighted shifts with scalar weights on the unit disk and the polydisk can be fitted into our general framework.

• Communications of the Korean Mathematical Society
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• v.13 no.1
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• pp.95-107
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• 1998

In this paper we prove the Hopf-Rinow theorem for CAT(0) spaces and show that the ideal boundaries of complete CAT(0) manifolds of dimension 2 or 3 with some additional conditions are homeomorphic to the circle or 2-sphere by the characterization of the local shadows around the branch points.

• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.1
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• pp.116-121
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• 2017

An additional root of the primary maxillary second molar is rarely observed. Two cases are presented herein, and we discuss a possible association between additional root of the primary maxillary second molar and displacement and rotation of the permanent successor. Investigation of crown morphology enables the detection of a potential additional root of the primary maxillary second molar, and eruption of the permanent successor needs to be examined carefully if an additional root is present. Early extraction of primary molar and space maintenance can be used as a conservative treatment if the premolar germ shows an abnormal eruption pattern.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.7
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• pp.633-639
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• 2007

This paper presents a new homing guidance law based on well-known BPN to achieve an impact time constraint as well as an impact angle constraint. The guidance commands are synthesized by introducing an additional command to control impact-time. The structure of the additional command has a BPN-based loop multiplied by time-varying gains being proportional to the time difference between the required time-to-go and the estimated time-to-go by BPN. Moreover, the proposed homing loop converges to BPN as the time-to-go error is reduced. The performance of the proposed guidance law is evaluated by the computer simulations.