• Korean Journal of Agricultural Science
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• v.8 no.2
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• pp.212-223
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• 1981

The proper nozzle spacings have been tried to determined the better evenness of distribution on the development of the boom type nozzle system with three nozzles made in Korea-disk type, cap type and bolt type. The operating pressure has been changed in 7 levels ($2kg/cm^2-8kg/cm^2$) and the operating height in 3 levels (30, 40, 50cm) to find characteristics of deposit pattern and the proper spacing of each nozzle was examined and computed. The results of this study were as follows; 1. The CU(%) of the deposit distribution was improved with the operating pressure of $5kg/cm^2$ or $6kg/cm^2$ in Nozzle A with 80% and Nozzle C with 83%, and $7kg/cm^2$in Nozzle B with 80% 2. The better deposit distribution was got ten at operating height 40cm with CU 86% in Nozzle A, and 50cm in both Nozzle B, C with 80% 3. The spray deposit distribution was getting of improvement with decrease of nozzle spacing, nevertheless about half diameter of the spraying circle was recommended in regard to the cost and the work performance. 4. Improvement of quality of nozzles tested in this research may be required not to be less than their CU 90% in the use as boom-type nozzle system.

• Journal of the Microelectronics and Packaging Society
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• v.21 no.3
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• pp.67-71
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• 2014

An attempt to grow high quality GaN on silicon substrate using metal organic chemical vapor deposition (MOCVD), herein GaN epitaxial layers were grown on various Si(111) substrates. Thin Platinum layer was deposited on Si(111) substrate using sputtering, followed by thermal annealing to form Pt nano-clusters which act as masking layer during dry-etched with inductively coupled plasma-reactive ion etching to generate nano-patterned Si(111) substrate. In addition, micro-patterned Si(111) substrate with circle shape was also fabricated by using conventional photo-lithography technique. GaN epitaxial layers were subsequently grown on micro-, nano-patterned and conventional Si (111) substrate under identical growth conditions for comparison. The GaN layer grown on nano-patterned Si (111) substrate shows the lowest crack density with mirror-like surface morphology. The FWHM values of XRD rocking curve measured from symmetry (002) and asymmetry (102) planes are 576 arcsec and 828 arcsec, respectively. To corroborate an enhancement of the growth quality, the FWHM value achieved from the photoluminescence spectra also shows the lowest value (46.5 meV) as compare to other grown samples.

• Korean Journal of Heritage: History & Science
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• v.52 no.4
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• pp.264-271
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• 2019

Cheomseongdae in Gyeongju, known as an astronomical observatory, is a cultural monument with great historical, academic, and artistic value, as its unique shape is preserved well in its original form. The outer structure, ground stability, and seismic reliability of Cheomseongdae have been assessed by numerous researchers through various scientific methods, but research on the underground structure has been insufficient. This paper contains detailed models of the underground structure of Cheomseongdae interpreted in 2D and 3D images based on the data acquired through GPR surveys conducted of features in and around the base of Cheomseongdae. As a result, the existence of twelve small features arranged in a circle, although only about half of them remain, was confirmed at a depth of 0.4 - 0.6m. Furthermore, a structure three bays long (north-south direction) and four bays wide (east-west direction) was detected beneath Cheomseongdae at the depth of 0.7 - 1.0m. Other than 2 layers of foundations as is known, a square structure with the dimensions of 7m × 7m is situated at a depth of 0.6m, directly under Cheomseongdae, and what is reading that is expected to be the foundation structure of Cheomseongdae was detected and confirmed. This foundation structure is circular with a diameter in the east-west direction of 11m and in the north-south direction of 12m. The northern, western, and eastern edges of this foundation structure are about 1m away from the foundation of Cheomseongdae, whereas the the south side extends to about 5m wide.

• Journal of Conservation Science
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• v.11 no.1 s.14
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• pp.15-27
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• 2002

The Buddhist Triad Cave in Gunwi, which consists of porphyritic biotite granite, has been deteriorated by a few weatherings. Origin of the weatherings is rain that can be leaked into the cave. Therefore the author investigates a few possible joints and bypasses leaking water, and reinforces any protective schemes for the rain influx. The porphyritic granite around the cave regularly develops two NEE and NWW joint sets. The NEE joint set could be divided into 4 joint zones among which $J_m\;and\;J_3$ may directly affect the leaking water into the cave. A extensional joint, in northern wall of the cave, runs through the $J_m$ joint zone. A small rain could rarely gets through the bypass, but a heavy rain has a good circulation through the joints to be leaked into the cave for a long time because of its long way. Many joints and cracks, in the ceiling near the cave entrance, immediately get to the $J_3$ joint zone, and have a good circulation of a small rain 10 mm. It is the desirable protective schemes that forbid rains to influx along the ranges from L -9 m to +10 m in the $J_m$ joint zone and upper half circle with radius 5 m in the $J_3$ joint zone. The joint apertures should be filled with a petro-epoxy and petro-filler to stop the water flow.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.570-575
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• 2019

Active muffler is implemented by applying active noise control technique to reduce exhaust noise of automobile muffler. Conventional Filtered_x LMS algorithm has a problem that the degree of control filter becomes very large and convergence deteriorates when acoustic feedback is present. The recursive LMS algorithm can compensate for this problem because it can be easily diverted in the adaptive filter adaptation process. In this paper, the structure of the primary path and the secondary path transfer function is designed as the IIR filter to improve the convergence performance and the computational burden, and the stabilization filter algorithm is applied to secure stability which is a disadvantage of the IIR filter structure. The stabilization filter algorithm plays a role of pulling the pole into the unit circle to prevent the pole of the transfer function corresponding to the acoustic feedback from diverging during the adaptation process. In this way, the computational burden of the active muffler system and the convergence performance can be improved. In order to show the usefulness of the proposed system, we compared the performance of the proposed Filtered_x LMS algorithm with the performance of the proposed system for the exhaust sound of a diesel engine, which is a variable environment. Compared to conventional algorithm, proposed algorithm's computational burden is less than half, and convergence performances are more than 4 times.

• Korean Journal of Metals and Materials
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• v.56 no.12
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• pp.861-869
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• 2018

To determine the origin of the inhomogeneous microstructure and texture observed in drawn and annealed high purity copper wires, two kinds of drawing process conditions and their influence was investigated. The regular condition, based on a symmetric die, and a condition designed intentionally to produce an inhomogeneous shear deformation using an asymmetric die were employed. The difference in intensity of <111>-<100> distributed texture between the two wires confirmed that the wire drawn under the asymmetric die condition experienced a higher amount of shear deformation. The extensive shear strain in the wire drawn under the asymmetric die condition gave rise to inhomogeneous primary and secondary recrystallization behavior. After annealing at $200^{\circ}C$, grains with <100> texture, which were larger than the surrounding recrystallized grains, were extensively present on one half circle of the wire drawn under the asymmetric die condition, while larger grains with <100> were sparsely observed around the middle region of the wire drawn under the regular condition. Interestingly, the area where the larger grains with <100> texture existed was identical to the area where the high shear strain occurred during drawing in both wires. During annealing at $400^{\circ}C$, grains with <112> texture started to grow abnormally at the center of both wires as a result of secondary recrystallization. After annealing at $900^{\circ}C$ grains with <112> due to secondary recrystallization occupied the entire region of the wire drawn under the regular condition. On the other hand, in the wire drawn under the asymmetric die condition and then annealed at $900^{\circ}C$, the <100> oriented grains as a result of the normal grain growth of the larger <100> grains which were observed after annealing at $200^{\circ}C$, coexisted with the abnormally grown <112> grains. These results indicate that dynamic recrystallization induced by the shear strain during drawing plays an important role in the inhomogeneity of the microstructure and texture of wires after annealing.

• Journal of the Korean Society of Costume
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• v.35
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• pp.45-66
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• 1997

This thesis is a study on the kaftan styles iin Asia. The purpose of he study was to examine the origin o the kaftan concentrating on the history and cultural backgrounds of nomads in he Western Central and North Eastern Asia. Secondly for more thorough study and expla-nation on how these kaftans contributed to East-West trade along the silk road. wall paintings and miniature illuminations along Oasis roads persia and Saracen period were compared, Also real kaftans were compared and analyzed the characteristics of Western (Turkey palestine) Central(Kazakistan Uz-bekistan Tadzhistan Qyrgyztan Turkmenistan) and the North Eastern Asian(Mongol) area. Thirdly an attempt has been made to provide the North Eastern Asian(Mongol) area. Thirdly an attempt has been made to provide the style classifications according to their peculiarities of the various kaftans as well as how kaftan gave important influences on custumes of different religious sects. The kaftan is a long coat-like garment with front openings fastened with long sash having an extra long sleeves which were worn by middle and high class nomadics throughout the West Central and North Eastern Asia This type of kaftans were a basic clothing for nomadics since they were constantly moving fromone to another areas on their horse back riding. They also wore tight trousers with boots. Kaftans seem to be originated from nomads of Steppe around B.C. 800 On B. C 400 west asian areas such as Solokha Kul-oba Kulogan had pictures sculptues on vases showing kaftans of half coat type length with front opening tied with band. Also the materials used were the products of animals such as wool or felt with animal designs showing Scythian nomads. In the North Eastern Asia Hsiung-Nu were active in Kazakha North Altai and Mongol The Clothing and fabrics exfavated near Noin-ula Pazyrik showed many samples of kaftan with trousers with other interment be-longings with a corpse around B.C 300 to A. D 100 when trades along the silk roads were proven by many historians Kaftans excavated in this area wore red front opening silk materials which suggesting settling down of nomads. in he central Asia Dol-gull near Altai mountain area were mainly miners who later had many trades with Persia and Bizantine. After Dol-gull Bezeklik temple Samarkant Kizil cow Budda sculture wall paintings of Astana tomb showed typical kaftan of this re-gion. These were both hip covered length as well as long coat with narrow sleeves. Es-pecially they had different color band fron the main kaftan with grogeously and splendously designed silk. In perusia during A. D 1400 to 1600 minia-ture illumination showed kaftan as a high class symbol more than clothing purpose. They had best quality silk with extra long sleeves draping and had a layers of kaftans one on top of anther as a symbol of wealth These Kaftans with different colors and designs were even more beautiful with their effective combinations and contrast of colors. On the other hand the lower class common people and servants wore simple kaftan with the front part of the kaftan were slipped into the belt in order to be more active and con-venient to work, The real kaftans discovered at Topkapi Saray palace of Turkey from A. D 1300 to 1900 were also compared. These kaftans were very numerous in numbers as well as designs The materials and designs used were also vari-ous such as Chinese to Italian silk. The shaped and pattern itself were not much different from the previous nomad's Kaftans. The Palestian kaftans remained were from the beginning of 19th and 20th century. Since this area is hot and dry desert they used black and navy blue colors mostly in order to exclude the sun lights. The patterns used were similar to Nomads and Bedouin with cross stiches and patch work decorations. In the central Asia they had similar life style and natural environmental cnditions with Turkish tribe which resulted in similar kaftan styles as nomads. Mongols conserved basic patterns of kaftan since Cinggis Khan with deep folding in order to keep warm. At last the kaftans studided in this thesis were classified in to four such as half coat long coat jacket and vest style. A pattern used in the Central Asia were zigzag and ani-mal design whereas in the West Asia were floral plant arabesk and circle pattern. As I discussed previously kaftan styles of nomads in the Asia maintained its basic pat-tern throughout the history except slight changes in color gusset sleeve shapes. These slight changes were made according to the need to adapt the need of environmental natu-ral conditions, The reason for aboriginality of kaftan in Asia was its simplicity and con-venience Most interesting fact is that for all these years Mongols are still wearing kaftan in their life ensuring us that they art the preserves of old kaftan. Since this thesis dealt enormous Asian regions I had a limitation of not being able to cover the Far Esatern asian areas such as Korea China and Japan how these kaftans were influenced in their clothing history as well as Eastern and Western culture. This topic along with the studies on materials and designs of patterns of kaftan will be another research project in the future.

• Progress in Medical Physics
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• v.22 no.3
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• pp.131-139
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• 2011

A method to get a size of the radiation isocenter of linear accelerators using star-shot images was presented and a computer program was developed to automate the method. Accuracy of the method was verified. The developed program was used to measure sizes of the radiation isocenters for a Clinac 21EX (Varian, USA) using data of quality assurance (QA) performed from June 2008 to December 2010. To calculated the size of radiation isocenter, positions of two points on each central ray of the star-shot image were found and the equation of the central ray was determined using the positions of two points. Using the equations of central rays the radius of the minimum circle intersecting all the central rays, which is one half of the size of radiation isocenter, was calculated. The program measured x-intercepts and y-intercepts of the central rays within errors of 0.084 mm and sizes of radiation isocenters within 0.053 mm. All the errors were less than the spatial resolution of star-shot images 0.085 mm. The radiation isocenter sizes of Clinac 21EX were $0.33{\pm}0.27mm$, $0.71{\pm}0.36mm$, $0.50{\pm}0.16mm$ for collimator, gantry and couch respectively. During the measurement period all the measured sizes were less than 2.0 mm and within tolerance. The developed program could calculate the size of radiation isocenters and it would be helpful to routine QA.

• Trans-
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• v.8
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• pp.95-127
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• 2020

This research is based on using Bartenieff Fundamentals to analyze the fundamentals of Tai Chi Chuan's movements in order to develop the methods of relaxation from Tai Chi Chuan's principle movement movements It also shows that the two techniques have commonalities in many ways. First of all, taking a philosophical approach on the body movements of Tai Chi Chuan and Bartenieff, for both methods the ultimate goal is the integration of mind and body. In other words, there is a thread of connection between the East's body and mind monism and the west's Body Awareness. Secondly, looking at it from a Breath Support standpoint as used in the Bartenieff method, the two methods both use the breathing to naturally move the body and relax the body. In Tai Chi Chuan the Breath is the basis of life and the strength of the Body. So the breathing of Tai Chi chuan is what makes body and mind communicate, harmonize and integrate. In other words, Breathing in Tai Chi is realized through mental fusion and affects the movements. This is the same as the Breath Support of Bartenieff. It is said that in every aspect the Breath Support of Bartenieff influences the movement and changes both the inner and outer form of the body. Thirdly, looking at the Core Support used in the Bartenieff method, both methods emphasize core. At the same time of moving and being conscious of one's core, the usage of muscles can be deeper rather than superficial and this enables strong and flexible movement. In Tai Chi Chuan abdominal muscles used when one coughs are consciously engaged through abdominal breathing and so strength is collected in the core. When one exercises like that the core becomes more stable and breathing becomes more smooth. Fourthly, analyzing the Rotary Factor used in the Bartenieff Fundamentals, they both use rotary movement to reach the goal of physical relaxation. The rotation factor of Bartenieff allows movement to be easier and more free because of the characteristic of joint exercise where the center axis moved in three dimensions, this is the same in Tai Chi chuan. According to Tai Chi chuan's circle and Spiral Movements, it can achieve the relaxation through switching into a seamless flow and access space as much as possible. Finally, when looking at Developmental Patterning through Bonnie Bainbridge Cohen's Body-Mind Centering Work theory, presented from Bartenieff developmental model are similar with the developmental process of Tai Chi chuan Breath, Core-Distal Connectivity/Navel Radiation, Head-Tail Connectivity/Spinal Movement, Upper-Lower Connectivity/Homologous, Body-Half Connectivity/Homo-Lateral Connectivity, Cross-Lateral Connectivity/Contra-Lateral Connectivity. They are all similar. In other words, in Tai Chi Chuan energy is gathered in the core through breathing, upper and lower body are connected through the spine, not only homo-laterally but also cross-laterally. Through this study the expression of the dance movements can be more natural. Additionally based on the Body Awareness balance usage of the central axis, joints and body can develop the relax technique.

• Korean Journal of Heritage: History & Science
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• v.43 no.3
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• pp.48-101
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• 2010

This paper estimated the calendar date of pottery with ring-rim(粘土帶土器) with the radiocarbon dating. This was based on archaeological facts with comparing line relations and radiocarbon dates of Yayoi pottery(彌生土器). As a result, I understood that pottery with circle ring-rim(圓形粘土帶土器) appeared in BC 6c, pottery with triangle ringrim(三角形粘土帶土器) appeared at the time in BC 300 . Based on the calendar date and aspect of ironware and pottery in grave, I kept in BC 4c with appearance date of ironware. And I kept in BC 5c with appearance date of the slim bronze dagger culture. Korea and Japan common chronological order were built for the first time based on radiocarbon dates, line relations of pottery with ring-rim and Yayoi pottery. This is the calendar date to date back approximately 100~300 years from the existing the calendar date. Current periodization does not match in the calendar date when I built it newly. Therefore I suggested it as follows. Early iron age is from the first~middle part BC 4c to BC 100. And the latter half of Bronze age is from BC 6c to the front appearance of ironware. Then Songguk-ri type(松菊里式) becomes staudard type of pottery in the middle stage of Bronze age.