• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.71.1-71.1
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• 2021

We perform disk-halo decomposition of the Large Magellanic Cloud (LMC) using a novel HI velocity field extraction method, aimed at better deriving its HI kinematics and thus mass distribution in the galaxy including both baryons and dark matter. We decompose all the line-of-sight velocity profiles of the combined HI data cube of the LMC, taken from the Australia Telescope Compact Array (ATCA) and Parkes radio telescopes with an optimal number of Gaussian components. For this, we use a novel tool, the so-called BAYGAUD which performs profile decomposition based on Bayesian MCMC techniques. From this, we disentangle turbulent non-ordered HI gas motions from the decomposed gas components, and produce an HI bulk velocity field which better follows the global circular rotation of the galaxy. From a 2D tilted-ring analysis of the HI bulk velocity field, we derive the rotation curve of the LMC after correcting for its transverse, nutation and precession motions. The dynamical contributions of baryons like stars and gaseous components which are derived using the Spitzer 3.6 micron image and the HI data are then subtracted from the total kinematics of the LMC. Here, we present the bulk HI rotation curve, the mass models of stars and gaseous components, and the resulting dark matter density profile of the LMC.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.60.3-61
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• 2020

We perform disk-halo decomposition of the Large Magellanic Cloud (LMC) using a novel HI velocity field extraction method, aimed at better deriving its HI kinematics and thus the dark matter density profile. For this, we use two newly developed galaxy kinematic analysis tools, BAYGAUD and 2DBAT which have been used for the kinematic analysis of resolved galaxies from Australian Square Kilometre Array (ASKAP) observations like WALLABY which is an all-sky HI galaxy survey in southern sky. By applying BAYGAUD to the combined HI data cube of the LMC taken with the Australia Telescope Compact Array (ATCA) and Parkes radio telescopes, we decompose all the line-of-sight velocity profiles into an optimal number of Gaussian components based on Bayesian MCMC techniques. From this, we disentangle turbulent non-circular gas motions from the overall rotation of the galaxy. We then derive the rotation curve of the LMC by applying 2DBAT to the separated circular motions. The rotation curve reflecting the total kinematics of the LMC, dark and baryonic matters is then be combined with the mass models of baryons, mainly stellar and gaseous components in order to examine the dark matter distribution. Here, we present the analysis of the extracted HI gas maps, rotation curve, and J, H and K-band surface photometry of the LMC.

• Journal of The Korean Association For Science Education
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• v.4 no.2
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• pp.64-73
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• 1984

This study aimed at identifying the characteristics of current science curriculum in several countries in terms of its format, aims and objectives, contents and guidelines and discussed about therm. The curricula were collected from 9 countries- The United States of America(5 states), Canada(4 Provinces), England, West Germany, France, Australia, Newzealand, Japan and the republic of China. Each country had her own characteristics of science curriculum, but there also common characteristics among several countries. First, the format of science curricula in eastern countries were very different from those of western countries. The western countries had the curriculum format which included characteristics and needs of science education, philosophy and background, aims and objectives, contents, characteristics of learners, teaching and learning strategy, teaching materials, guide of experiments, evaluation methods, and other concrete informations while eastern countries had the curriculum format which included only objectives, contents and guidelines. I think that the format of science curriculum in western countries is more recommendable than that of eastern countries. Second, the aims and objectives of science curricula in eastern countries focused on scientific knowledges and concepts, while those of countries emphasized scientific methods and attitudes. Third, the contents of science curricula were very similar regardless of eastern countries or western countries. In other words, all the countries in this study emphasized life science and earth science at lower grade level and physical science at upper grade level. Especially the observation and concrete learning activities were suggested at lower grade level and logical reasoning was emphasized at upper grade level. I think that the integrated (topic-centered) science curriculum is more recommendable than our current non-integrated science curriculum in lower grade levels. Finally, the guidelines of science curriculum in eastern countries did not suggest specific information about teaching contents, experimental methods, teaching-learning activities, evaluation methods, teaching and learning meterals, while those of western countries provided more specific information which teachers could utilize very effectively.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1996.04a
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• pp.22-22
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• 1996

;The Kwinana Shoreline Fumigation Experiment(KSFE) took place in Fremantle, WA, Australia between 23 January and 8 February, 1995. All measurement systems performed to expectation. The CSIRO DAR(Division of Atmospheric Research) LIDAR measured plume sections from near the Kwinana Power Station(KPS) stacks to up to about 5 km downstream. It also measured boundary layer aerosols and the structure of the boundary layer on some occasions. Both stages A and C of KPS were used as tracers at different times. Radiosonde and double theodolite sounding systems measured temperature, humidity, air pressure and wind structure at the coast(Woodman Point) and at the inland(ALCOA residue dump) site at intervals of roughly two hours. These were supplemented by mid afternoon soundings(radiosonde and single theodolite) by Department of Environmental Protection(DEP) at Swanbourne. The Flinders aircraft measured wind, turbulence and temperature structure of the atmospheric boundary layer, concentrations of $C0_2,\;0_3,\;S0_2\;and\;NO_x$ in the smoke plumes and surface radiation over both land and sea. CSIRO DCET(Division of Coal and Energy Technology) vehicle successfully interceptde many smoke plumes and using a range of tracers will be able to identify the various sources much of the time. Routine data from the DEP and Kwinana Industrial Council(KIC) air quality monitoring networks were also automatically logged. Murdoch University measured surface heat flux at Hope Valldy monitoring station and also at Wattleup monitoring station for the last five days. The heart of the LIDAR system is a Neodymium-doped Yttrium-aluminumgarnet(Nd:Y AG) laser operating at a fundamental wavelength of 1064 nm, with harmonics fo 532 nm and 355 nm. A small fraction of the laser beam is scattered back to the LIDAR, collected by a telescope and detedted by a photomultiplier tube. The intensity of the signal as a function of time is a measure of the particle concentration as a function of distance along the line of the laser shot. The results of nine days special field observations are summarized in detail.etail.

• The Korean Journal of Archival Studies
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• no.10
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• pp.145-194
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• 2004

Church archives are the evidential instruments to remember church activity and important information aggregate which has administrative, legal, financial, historical, faithful value as the collective memory of church community. So it must be managed necessarily and the management orders are based on the Bible. The western churches which have a correct understanding about the importance of church records and management order have taken multilateral endeavor to create, manage church archives systematically. On the other hand, korean churches don't have the records management systems. Therefore, Records created in individual church are mostly managed unsystematically and exist as 'backlogs', finally, they are destructed without reasonable formalities. In those problems, the purpose of this study is to offer the way of records classification and disposition instrument with recognition that records management should be done from the time of creation or previous to it. As a concrete device for them, I tried to embody the function-based classification method and disposal schedule. I prefer the function-based classification and disposal schedule to the organization and function-based classification to present stable classification and disposal schedule, as we can say the best feature of the modern organization is multilateral and also churches have same aspect. For this study, I applied DIRKS(Designing and Implementing Recordkeeping Systems) manual which National Archives of Australia provide and guidelines in ICA/IRMT series to construct the theory of the function-based classification in individual churches. Through them, it was possible to present a model for preliminary investigation, analysis of business activity, records survey, disposal schedule. And I took an example of 'Myong Sung Presbyterian Church' which belong to 'The Presbyterian church in Korea'. I explained in detail codifying process and results of preliminary investigation in 'Myong Sung Presbyterian Church', analysis of business activity based on it, process of presenting the function-based classification and disposal schedule got from all those steps. For establishing disposal schedule, I planned 'General Disposal Schedule' and 'Agency Disposal Schedule' which categorized 'general function' and 'agency function' of an agency, according to DIRKS in Australia and ICA/IRMT. And for estimation of disposal date I had a thorough grasp of important records category presented in 'Constitution of General Assembly', interview to know the importance of tasks, and added examples of disposal schedule in western church archives. This study has significance that it was intended to embody 'the function-based classification' and 'disposal schedule' suitable for individual church, applying DIRKS in Australia and ICA/IRMT on absence of the theory or example which tried to present the function-based classification and disposal schedule for individual church. Also it is meaningful to present a model that can classify and disposal real records according to the function in individual church which has no recognition or way about records management.

• Pediatric Infection and Vaccine
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• v.31 no.1
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• pp.1-11
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• 2024

Despite improvements in vaccine coverage, a resurgence of measles has been reported, especially in the infant and adult populations in recent years. We conducted a systematic review of seroprevalence studies conducted in the Western Pacific Region (WPR) to provide insights into seropositivity trends in different countries. This systematic review aimed to collect data from all available measles seroprevalence studies to characterize the differences in population immunity against measles in different countries. We searched the online databases PubMed and Embase to identify: 1) observational studies that investigated seroprevalence in all age groups, and 2) results reported as antibody levels. The following variables were extracted from different study arms: paper identification (title, first author, publication year), inclusion and exclusion criteria, study site, age of subjects, number of subjects, country/area, population, methods, and seropositivity (%). The search yielded a total of 69 studies included in the review. Among the 1-6-year-old group, seropositivity remained relatively high, at 81-100% in China, 86-94% in Korea, and 77-91% in Australia. In adolescents aged 7-18-years old, seropositivity was relatively constant in China and Australia over time; however, a decreasing trend was noted in Korea in 2011 (66%), 2014 (69%), and 2014 (50%) in this age group. A similar downward trend was observed among Korean adults aged 19-39 years in 2011 (74%), 2019 (71%), and 2019 (64%). Children are likely to be protected by universal vaccination programs in WPR countries and regions. However, susceptible individuals with waned immunity may be present among the adult population.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.05a
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• pp.89-92
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• 2001

Drop weight impact tests were performed to investigate the impact behavior of carbon fiber/epoxy composite laminates reinforced by short fibers and other interleaving materials. Characterization techniques, such as cross-sectional fractography and scanning acoustic microscopy, were employed quantitatively to assess the internal damage of some composite laminates. Scanning electron microscopy was used to observe impact damage and fracture modes on specimen fracture surfaces. The results show that composite laminates experience various types of fracture; delamination, intra-ply cracking, matrix cracking and fiber breakage depending on the interlayer materials. Among the composite laminates tested in this study, the composites reinforced by Zylon fibers showed very good impact damage resistance with medium level of damage, while the composites interleaved by poly(ethylene-co-acrylic acid) (PEEA) film is expected to deteriorate the bulk strength due to the reduction of fiber volume fraction, even though the damaged area is significantly reduced.

• The Korean Journal of Soil Zoology
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• v.9 no.1_2
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• pp.16-23
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• 2004

This study estimated the mound and termite population density in the two study plots in Durokkopin Nature Reserve, Western Australia between 2003 and 2004. The mound density and size were greater in the woodland than in the shrubland. The annual growth rate of mounds was minimal. Some mounds decreased in volume during the 14 month observation period in both study plots. There were no significant differences in the termite population per mound or in the proportion of each caste between the two study plots. The size of the termite population in the mound progressively increased from the small to larger mounds. Overall, of the two favoured habitats, woodland appears to be more optimal for this termite species than the shrubland.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.3
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• pp.208-214
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• 1996

This trial was conducted at two locations to compare forage yield, plant height, disease reaction, lodging and maturity of oat(Avm sativa L.) cultivars introduced from Western Australia in comparison with the control cultivar of oat 'Cayuse" over a period of 3 yr. At Suweon, Swan and Murray cultivars gave the highest forage yield, followed by Winjardie and Hay cultivars during 3 years of trial, but Cayuse cultivar gave the lowest forage yield. At Sunghwan, Hay and Swan cultivars tended to forage yield more than other cultivars, but Cayuse cultivar was among the lowest yielding. AU the cultivars in the trial were moderately resistant to BYDV and lodging at two locations although differences exist among cultivars. Murray cultivar was early in maturity, while Swan, Hay and Winjardie cultivars showed medium, and Cayuse cultivar was later. Murray and Swan cultivars were tall in height and gave a higher dry matter percentage of 18~20% at harvest. The results of the trial indicated that Swan and Murray cultivars could be recommended as the national recommended forage oat cultivar when forage performance was considered.ered.

• Structural Engineering and Mechanics
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• v.33 no.6
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• pp.765-779
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• 2009

Quantitative condition assessment of structures has been traditionally using proof load test leading to an indication of the load-carrying capacity. Alternative approaches using ultrasonic, dynamics etc. are based on the unloaded state of the structure and anomalies may not be fully mobilized in the load resisting path and thus their effects are not fully included in the measured responses. This paper studies the effect of the load carried by a reinforced concrete beam on the assessment result of the crack damage. This assessment can only be performed with an approach based on static measurement. The crack damage is modelled as a crack zone over an area of high tensile stress of the member, and it is represented by a damage function for the simulation study. An existing nonlinear optimization algorithm is adopted. The identified damage extent from a selected high level load and a low load level are compared, and it is concluded that accurate assessment can only be obtained at a load level close to the one that creates the damage.