• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.3
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• pp.388-402
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• 2000

The radiation characteristics of leaky antenna from the dielectric-coated conducting cylinder with periodic corrugation are investigated theoretically for the infinite and finite periodic structures. For the infinite periodic structure, mode-matching method is applied. The integral equation is derived for the finite periodic structure by use of the Fourier transform and mode expansion and a simultaneous linear equation is obtained. The influences of the corrugation slot width, corrugation depth, dielectric thickness, cylinder radius, and finite corrugation number on the radiation characteristics (leakage constant, phase constant, and radiation pattern) are investigated. The results of the finite periodic corrugations are compared with those of the infinite extent structure and good agreement is found. To reduce high side lobe levels of the uniform finite periodic structure, tapering process on the beginning and end section of antenna and nonuniform quasi-period slot arrays are considered. Especially, for the corrugation period, width and depth used for a corrugated surface wave antenna, through the proper tapering process, end-fire radiation pattern with reduced side lobe levels is given.

• Journal of Home Health Care Nursing
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• v.12 no.1
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• pp.117-135
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• 2005

Purpose: Expecting a new system of nursing security for elderly in operation in 2007, a substantial expansion of nursing facilities for elderly and quality management of those facilities are imperative now. Therefore. specific quality management measures or schemes which could be used for the operation of small-scale nursing homes are in urgent need. The purpose of this study was to develop a Quality Management Index(QMI) to guide Nursing Home management. Method: This study developed a QMI for small-scale nursing homes, which focused on quality management in structural dimensions such as environment, staffs, local community network, atmosphere, and quality management in process dimensions such as nursing, communication, resident satisfaction. The QMI developed in this study is based on extensive review of literature and the actual experiences of nursing home operation. It consists of 7 dimensions, 39 components and 148 indexes, which have been verified by three times validity tests of experts group. Then the QMI was used to evaluate the quality management levels of nursing homes in Korea. Result: In sum, after analyzing all nursing homes in Korea operated by nurses, this study found that there were significant differences of quality management level among facilities in several dimensions such as environment, staffs, local community connections, communication. In dimensions such as nursing, atmosphere, resident satisfaction, however, little differences of quality management level among facilities were reported. It is considered that this result has to do with several factors like the size of facilities, operation expenses, operation forms, the disposition of professional human resources, and philosophy and management policy of the owners. As far as generalization is concerned, however, it needs to be noted here that the sample size for this study is not statistically big enough to generalize the results. Conclusion: Having Developed a QMI for small-scale nursing home with 7 dimensions, 39 components and 148 indexes, this study is expected to be used in developing more elaborated quality evaluation tools for nursing homes, and also function as a practical guide of quality management for those who are opening and managing nursing homes. I hope this quality index could lead to further development of a standardized quality management index, and eventually contribute to quality improvement of nursing homes.

• Journal of Hydrogen and New Energy
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• v.28 no.3
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• pp.238-245
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• 2017

Mg-Ni nanoparticles were synthesized by a physical vapor condensation method (DC arc-discharge) in a mixture of argon and hydrogen atmosphere, using compressed mixture of micro powders as the raw materials. The crystal phases, morphology, and microstructures of nanoparticles were analyzed by means of X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). It was found that the intermetallic compounds of $Mg_2Ni$ and $Mg_2Ni$ formed with existence of phases of Mg, Ni, and MgO in Mg-Ni nanoparticles. After one cycle of hydrogen absorption/desorption process (activation treatment), Mg-Ni nanoparticles exhibited excellent hydrogen absorption properties. $Mg_2Ni$ phase became the main phase by aphase transformation during the hydrogen treatments. The phenomenon of refinement of grain size in the nanoparticle was also observed after the hydrogen absorption/desorption processes, which was attributed to the effect of volume expansion/shrinkage and subsequent break of nanoparticles. Maximum hydrogen absorption contents are 1.75, 2.21 and 2.77 wt.% at 523, 573 and 623 K, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.04b
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• pp.157-160
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• 2004

Ferroelectric $(Ba_xSr_{1-x})TiO_3$ (BST) thin films have been deposited on (001) MgO single crystals by a pulsed laser deposition (PLD) method. The structure of deposited BST thin films were investigated by an x-ray diffractometer. Calculated c-axis lattice parameters of the BST films exhibit a strong lattice distortion, which was not observed in ceramic BST at room temperature. This lattice distortion of BST has been attributed to strains caused by lattice constant difference between film and substrate, oxygen vacancies in BST film, and thermal expansion difference between film and substrate. Ferroelectric properties at 10 GHz have been measured using a HP 8510C vector network analyzer. Dielectric properties, capacitance tunability and quality factor, of the interdigitaed capacitors fabricated on BST films were calculated from the measured s-parameters. Two distinct behaviors in structural, opitical, and microwave properties of BST films were observed; below and above 200 mTorr of oxygen pressure in the deposition chmber.

• Korean Institute of Interior Design Journal
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• v.13 no.5
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• pp.106-113
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• 2004

The purpose of this study is to present the dwelling space by attaching or inserting the mobile space unit to the fixed building by providing the temporary dwelling space for those suffering from flood disaster, natural disaster or solitary old people or the space and program that the completed building in the city can not provide such as temporary events in the bridge, passage space, walking space for the handicapped, stores located between street blocks, and plaza. Therefore, this study was intended to investigate temporary dwelling space through the composition of space and the experiment of the applicability of the program through the methods of movement, folding, module, expansion and evolution of mobile space. An attempt was made to apply the concept of ‘mobile space’ to the dwelling space not only with a focus on the freedom of variable and changeable physical movement but also with a focus on the existence of the nomad and the way of thinking that bleaks away from a given value system and code, creates a new value and continues to move to a new domain. This study attempted to analyze how the concept of ‘mobile space’ has been developed in what form and method they have been applied and interpreted in the historical background. It attempted to resolve the concepts of movement and mobility through the experiment so that they might apply to the space of contemporary city. This study attempted to experiment this possibility using the mobile space unit and apply it.

• Journal of the Korean GEO-environmental Society
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• v.10 no.7
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• pp.43-51
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• 2009

This paper holds three objects. The first is to analyze surveys of concerning zone and promotion department. The data were collected through an examination of construction excavated in coastal soft (marine) clay and measurements obtained during excavating construction. The second is to observe the appropriate selection and the application of support system on earth retaining wall in soft clay. Lateral deformation behavior during the excavating construction according to the differences in a soft ground pressuring degree was investigated. The third is to compare the results with those of numerical analysis. Therefore, the purpose of this study is to analyze the characteristics of lateral deformation when soft ground improvement for the expansion of infrastructure in object of study zone has been incompleted. Also, it is to identify the relationship between the degree of consolidation of soft ground and lateral deformation, in a method of displacement quantity in compliance with the numerical analysis and a quatitative analysis. In conclusion, displacement of excavated section after consolidation was fewer 60% averagely than section under consolidation.

• BMB Reports
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• v.29 no.5
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• pp.429-435
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• 1996

To investigate the structure-antagonistic relationship of the cyclohexapeptide L-659,877, a selective NK-2 tachykinin receptor antagonist, seven analogues were chemically synthesized by a solid phase method. The agonistic and antagonistic activities of the analogues were evaluated by contraction assay using the smooth muscle of guinea pig trachea (GPT) containing the NK-2 receptor. It was shown that the aromatic ring of Phe at position 3 and the sulfur group of Met at position 6 in L-659,877 were essential for binding to the NK-2 receptor. Decrease in antagonistic activity of L-659,877 caused by substituting Leu for Nle at position 5 indicates that the ${\gamma}$ methyl group and side chain length of Leu plays an important role in its antagonistic action. Although the activity was slightly lower than L-659,877, cyclo $[{\beta}Ala^{8}]NKA(4-10)$ (analogue 1) showed potential antagonistic activity for the NK-2 receptor. It was confirmed that the expansion of the ring in L-659,877 by substitution of ${\beta}Ala$ for Gly at position 4 stabilized its conformation monitored by CD spectra. The results suggest that analogue 1 can be used as a new leader compound to design a more powerful, selective, and stable NK-2 receptor antagonist.

• Journal of the Korean Society of Costume
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• v.62 no.4
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• pp.1-14
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• 2012

Ever since the year 2000, Korea's musical markets has invited famous overseas license performances and have therefore cooperated with staffs working overseas in regards to stage costumes. This study aims to suggest the methodology of the stage costume making process according to the present advanced production system of Korea's musical market. The researcher participated in the stage costume making work of 'Chicago' as a costume supervisor. It took place at the Opera House of Seongnam Art Center from January 10, 2010 to February 28, 2010. Furthermore, there was significance in reinforcing academic values and implementing practical making process of stage-costumes based on the actual field work. The method of this research was carried out through a theoretical research and a case study that focused on empirical research. As for the research scope, it was limited to the actual stage-costumes that the researcher fully engaged with as a costume supervisor of the musical 'Chicago.' The results of this study were as follows. The stage costume making process of the musical 'Chicago' was categorized according to the classification of production system in the performance. For pre-production, it was divided according to the information of the actor and the analysis of the bible. Rehearsal period was divided according to the product clothes and fitting. Production week & preview were divided according to the changeover of clothes and the arrangement of dressers. The Run was divided according to the inspection of the situation concerning clothes in general during the performance. Post-Production Period was divided according to the collection of clothes and the implemented database. This study eventually suggested appropriate stage-costume making processes for the costumes making environment according to the expansion of overseas license musical market. However, it has a limitation of the research scope to the musical 'Chicago.' The creative performances of the domestic version are planned in diverse forms and come to abroad animate by the Korean Wave. Therefore, the field of stage-costume is necessary for the establishment of practical schemes of the system and copyright in accordance with the environment.

• Journal of Advanced Marine Engineering and Technology
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• v.26 no.1
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• pp.37-47
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• 2002

Recently gasoline direct injection method has been applied to gasoline engine to reduce fuel consumption rate by controlling fuel air mixture on lean condition by means of stratified charging, and to reduce simultaneously. Pollutant emissions especially NOx and CO by lowering the combustion temperature. But difficulty of controling local fuel air ratio at ignition area in flammability limit unavoidably appeared, because it is merely controlled by injection timing with spatial and temporal distribution of fuel mixture. In this study, the authors devised a uniquely shaped combustion chamber so called three-chamber GDI engine, intended to keep the more reliable fuel air ratio at ignition area. The combustion chamber is divided into three regions. The first region is in the rich combustion division, where the fuel is injected from the fuel injection valve and ignited by the spark plug. The second region is in the lean combustion division, where the combustion gas from the rich combustion division flows out and burns on lean condition. And the last region is in the main combustion division ie in the cylinder, where the gas from the above two combustion divisions mixed together and completes the combustion during expansion stroke. They found that the stable range of operation of three-chamber GDI engine on low-load condition exists in the lean area of average equivalence ratio. And they also found that the reformed engine reveals less specific fuel consumption and less pollutant emissions compared with conventional carburettor type gasoline engine.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.4
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• pp.425-431
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• 2011

Thermal energy generated because of the friction between the disc and pad is transferred to both sides and causes thermal expansion of the material, which affects the contact pressure distribution. This phenomenon, which is called thermoelastic instability (TEI), is affected by the natural mode of a disc. TEI results in the formation of a hot spot and causes hot judder vibrations. In this study, three-dimensional analysis of the hot judder of a ventilated disc for automotives was performed by using the commercial finite element analysis program, SAMCEF. The intermediate processor based on a staggered approach was used to exchange the result data of the mechanical and thermal model. The hot spot was formed on the surface of the disc, and the number of hot spots was compared with the natural mode of the disc.