• Journal of the Korea Safety Management & Science
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• v.16 no.4
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• pp.433-439
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• 2014

Beam quality is changed about magnetic field of bending magnet. Evaluation of beam quality using PDD(Percentage Depth Dose) at 10cm depth at recommendation of AAPM(America Academy of Pain Medicine). However this evaluation shows fragmentary element. Therefore this study is applied to three value, 10cm divided by 5cm depth PDD, 20cm divided by 10cm depth PDD, 30cm divided by 20cm depth PDD, at change the magnetic field. PDD is measured at magnetic field changed ${\pm}1%$, ${\pm}2%$ at 6MV(Mega Voltage), 10MV photon. The plan technique is 3 portal plan using Core-Plan at human pelvic phantom. Conventional and presented methods are compared at maximum and minimum dose. The presented method increased discernment of relieve the unequal distribution and energy area than conventional method. Henceforth, application of presented method will be considered. Development of energy measurement method and detector miniaturization will be needed about continuous study.

• The Research Journal of the Costume Culture
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• v.17 no.6
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• pp.1068-1082
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• 2009

The purpose of this study was to investigate empirically the consumer behavior regarding the purchase of millinery items in relation to their evaluation criterion and demographic characteristics. The survey was carried out to 395 individuals in their 20s and over who were quota sampled according to age and gender. The collected data were statistically treated with the SPSS 12.0 program in terms of descriptive statistics, cross tabulation, t-test, one-way ANOVA, factor analysis, Cronbach's $\alpha$ coefficient and Duncan-test. The 20s and 50s over were more interested in hat products than other ages. Female consumers obtained the most information about hat products from store visits, TV and magazines. On the other hand, male consumers had it from the acquaintances and internet. Younger consumers more often utilized internet to have it. Their main purchase location was department stores. The younger purchased it more in traditional market, the older purchased it more in mega wholesale market or discount store. The consumers of hat products considered the intrinsic classification most when buying hats. The evaluation criteria employed by them were aesthetics, quality, and external attributes. Hat consumers were more concerned about aesthetics attributes than the other two criteria. Female consumers and consumers who are more interested in the hat and have a higher level of education and income considered aesthetics attributes most important.

• International Journal of High-Rise Buildings
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• v.5 no.2
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• pp.87-94
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• 2016

High-rise as a building typology is gaining popularity in Asian mega-cities, due to its advantages in increasing volumetric density with limited land resources. Numerous factors contribute to the formation of high-rise urban form, from economical and institutional, environmental to socio-political. Environmental concerns over the impact of rapid urbanization in developing economies demand new thought on the link between urban environment and urban form. Outdoor and indoor climate, pedestrian comfort, and building energy consumption are all related to and impacted by urban form and building morphology. There are many studies and practices on designing individual "green" high-rise buildings, but far fewer studies on designing high-rise building clusters from the perspective of environmental performance optimization.. This paper focuses on the environmental perspective, and its correlation with the evolution of the high-rise urban form. Previous studies on urban morphology in terms of environmental and energy performance are reviewed. Studies on "parameterizing" urban morphology to estimate its environmental performance are reviewed, and the possible urban design implications of the study are demonstrated in by the author, by way of a microclimate map of the iconic Shanghai Xiao Lujiazui CBD. The study formulates the best-practice design guidelines for creating walkable and comfortable outdoor space in a high-rise urban setting, including proper sizing of street blocks and building footprint, provision of shading, and facilitating urban ventilation.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.497-500
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• 2008

Recently, the urban regeneration project has been performed actively at home and abroad. The stake-holders in urban regeneration project are various and complicated, and has large scale during a long life period. Also they show the characteristics of a mega-project and most mixed-use form. Therefore, the urban regeneration has a lot of potential risk factors from project beginning to completion. It means they need efficient and continuous risk management in terms of performance measurement. But the current domestic construction project does not reflect risk management in view of performance measurement. This study proposes the risk management methodology by mapping risk factors with major performance indexes of the urban regeneration project.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.46.2-46.2
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• 2014

Galaxy morphology is involved complex effects of both secular and non-secular evolution of galaxies. Although it is a final product of a galaxy evolution, it may give a clue for the process that the galaxy suffer. Galaxy clusters are the sites where the most massive galaxies are found, and the most dramatic merger histories are embedded. Morphology study in nearby universe, e.g. Virgo cluster, is well established, but for clusters at z ~ 0.1 it is only focused on bright galaxies due to observational limits. Our optical deep imaging of 14 Abell clusters at z = 0.014 - 0.16 using IMACS f/2 on a Magellan Badde 6.5-m telescope and MegaCam on a 3.8-m CFHT enable to classify detailed morphology. For the galaxies in our data, we investigated their morphology with several criteria related to secular or merger related evolution. Our research on detailed morphology of thousands of galaxies through deep imaging would give a general census of cluster galaxies and help to estimate the evolution of cluster galaxies.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.1
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• pp.40.1-40.1
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• 2013

The HI ring serendipitously found in the Leo I galaxy group is unique in size in the Local Universe. It is ~200kpc in diameter with MHI~$1.67{\times}109M{\odot}$, surrounding a pair of early type galaxies M105 and NGC 3384. Its origin is still under debate whether it is the remnant of formation of a galaxy group (primordial) or formed from stripped material during galaxy-galaxy interaction (tidal origin). Intriguingly a number of dwarf galaxies have been identified along the gas ring (with or without optical counterpart). Various properties of these dwarf galaxies such as dark matter content, color, and/or metallicity will allow us to pin down the origin of this large scale HI ring. We have obtained a mosaicked CFHT MegaCam image and the EVLA HI cube of the large scale gas ring. In this work we present optical and gas properties of dwarf galaxies identified in the CFHT data.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.70.2-70.2
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• 2016

Star formation in galaxies is one of the key factors in galaxy evolution. It is believed that star formation is triggered and enhanced by mergers among galaxies or secular evolution. However, how much these two mechanisms contribute on star formation is not well known yet. Recently, many other studies show observational evidences of faint merger features(tidal tails, stellar streams) around nearby galaxies with deep optical imaging. This study aims to investigate the fraction of star forming galaxies exhibiting faint features to total galaxies. We are analyzing samples of 76 star forming galaxies (NUV < -18) to find merger features from stacked B, R band frames taken at Maidanak 1.5m, McDonald 2.1m telescope and g, r frames from Canada-France-Hawaii Telescope (CFHT) MegaCam archival data. With the fraction, we can expect to know the contribution of mergers on star formation to galaxies.

• Journal of Navigation and Port Research
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• v.33 no.5
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• pp.353-359
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• 2009

Most domestic container terminals are lack of container storage capacity compared to the throughput of container. The main reason is the difference between the theoretical capacity applied to the development of terminals and the real capacity of a berth Another reason seems to be the increase of the container crane in number per berth to match the need for the getting larger vessel, which is resulted from the increase of the berth capacity from the start. This study, therefore, aims to suggest the economic size of container yard by comparing the existing one. For this the berth capacity was recalculated, the required yard size derived considering up to 10,000TEU vessel and then cost comparison done.

• Progress in Superconductivity and Cryogenics
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• v.19 no.3
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• pp.49-53
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• 2017

The superconducting magnets have a large inductance as well as high operating current. Therefore, mega-joule scale energy can be stored in the magnet. The energy stored in the magnet is sufficient to damage the magnet when a quench occurs. Quench heater and dump resistor can be used to protect the magnet. However, using quench heater to create quench resistors through heat transfer can be slower than instantly switching resistors. Also, electrical short, overheating and breakdown can occur due to quench heater. Moreover, the number of dump resistor should be limited to avoid large terminal voltage. Therefore, in this paper, we propose a quench protection method for extracting the energy stored in a magnet by charging and discharging energy through a capacitor switching without increasing resistance. The simulation results show that the proposed system has a faster current decay within the allowable voltage level.

• Journal of the Korea Institute of Building Construction
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• v.9 no.2
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• pp.47-54
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• 2009

Integrated construction site management using RFID(Radio Frequency Identification) and facility maintenance introducing USN (Ubiquitous Sensor Network) have been widely used in the mega construction project sites. But, the validation on performance of RFID systems after introducing those has not been carried out. Given that the use of RFID systems have been increased, the construction industry as well as other industries needs the evaluation of the RFID system. By regarding the necessities for evaluation, a research to the satisfaction and importance evaluation of RFID system from the end-users' view point for site management was conducted. Satisfaction-importance matrix of satisfaction standards and importance standards was created (organised) according to the analysis result of a survey, proposed improvement methods and analysis about the items presented by each region like areas of sustainable maintenance, maintenance, progressive improvement and priority improvement. The result would contribute to enhance the utilization of system and its performance.