• Title/Summary/Keyword: Seong-Ho School

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Anisotropy in a Few mm Regions from an Ir192 High Dose Rate Source Measured with a GafChromic Film in Acrylic Phantom (아크릴 팬톰에서 GafChromic 필름을 이용한 고선량률 근접 치료용 Ir-192 선원의 근접 거리에서 비등방성 측정)

  • Huh, Hyun-Do;Kim, Seong-Hoon;Park, Jin-Ho;Cho, Byung-Chul;Shin, Dong-Oh;Soo il Kwon;Chun, Ha-Chung;John J K Loh;Kim, Woo-Chul
    • Progress in Medical Physics
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    • v.15 no.2
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    • pp.94-99
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    • 2004
  • Radiochromic film has several advantages; high spatial resolution, relatively low spectral sensitivity, near tissue equivalence and requires no special development procedure. The object of this study was to measure the anisotropy of an Ir-192 source (microSelectron manufactured by Nucletron) in a few mm regions from the source, using the GafChromic film. The GafChromic film was calibrated in the range of 0∼105 Gy, using a 4 MV photon beam, and the anisotropy function measured in an acrylic phantom using the GafChroimic film. The data obtained gave agreement to within 4.4% of the Monte Calro calculation, by J. F. Williamson, at a radial distance of 2.5 mm with polar angles of 50 to 130$^{\circ}$, while a maximum deviation of 17.6% was observed at angles near 140$^{\circ}$and agreement within 3.7% at a radial distance of 5 mm at polar angles between 35 to 150$^{\circ}$ and a maximum deviation of 7.6% was observed at angles near 30$^{\circ}$. A GafChromic film can be used as a more efficient detector for measuring the anisotropy of an HDR $^{192}$ Ir source at close distances than any other detector.

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Chamber-to-chamber Variations in the Same Type of a Cylindrical Chamber for the Measurements of Absorbed Doses (흡수선량 측정 시 동종 원통형 이온함에서 이온함 간 변화)

  • Kim, Seong-Hoon;Huh, Hyun-Do;Choi, Sang-Hyun;Kim, Hyeog-Ju;Lim, Chun-Il;Shin, Dong-Oh;Choi, Jin-Ho
    • Progress in Medical Physics
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    • v.21 no.1
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    • pp.120-125
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    • 2010
  • For the measurements of an absorbed dose using the standard dosimetry based on an absorbed dose to water the variety of factors, whether big, small, or tiny, may influence the accuracy of dosimetry. The beam quality correction factor ${\kappa}_{Q,Q_0}$ of an ionization chamber might also be one of them. The cylindrical type of ionization chamber, the PTW30013 chamber, was chosen for this work and 9 chambers of the same type were collected from several institutes where the chamber types are used for the reference dosimetry. They were calibrated from the domestic Secondary Standard Dosimetry Laboratory with the same electrometer and cable. These calibrated chambers were used to measure absorbed doses to water in the reference condition for the photon beam of 6 MV and 10 MV and the electron beam of 12 MeV from Siemens ONCOR. The biggest difference among chambers amounts to 2.4% for the 6 MV photon beam, 0.8% for the 10 MV photon beam, and 2.4% for the 12 MeV electron beam. The big deviation in the photon of 6 MV demonstrates that if there had been no problems with the process of measurements application of the same ${\kappa}_{Q,Q_0}$ to the chambers used in this study might have influenced the deviation in the photon 6 MV and that how important an external audit is.

Cloning of the posterior silk glands specific-expressed gene of silkworm (누에 후부실샘 특이 발현 유전자 클로닝)

  • Piao, Yulan;Kim, Seong-Ryul;Kim, Sung-Wan;Kang, Seok-Woo;Goo, Tae-Won;Choi, Kwang-Ho
    • Journal of Sericultural and Entomological Science
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    • v.53 no.1
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    • pp.44-49
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    • 2015
  • We characterized tissue specific-expressed genes in the posterior silk gland of Bombyx mori using by the Annealing Control Primer based differential display-PCR manner. In this study, we isolated 34 differentially expressed PCR amplicons, which one of these was identified as a novel transcript named as ACP-16 (366 bp), its expression was observed only in the posterior silk glands by Northern blot analysis. To determine promoter region of the ACP-16, we isolated and analyzed a phage DNA having 1.7 kb-long genome DNA including the open reading flame and 5'- upstream untranslated region of the ACP-16 gene from a genomic DNA library. We have estimated a promoter region of the ACP-16 gene by a web promoter prediction engine, which locates -750 ~ -165 from translation initiation site (ATG, +1). ACP-16 gene is necessary to more studies about critical biological role in order to apply the silkworm's transgenic system.

Improvement of Transglycosylation Efficiency using a Glycosynthase Mutant derived from Thermoplasma acidophilum ${\alpha}$-Glucosidase (Thermoplasma acidophilum 유래 ${\alpha}$-glucosidase로 부터 생산된 glycosynthase 돌연변이 단백질의 개선된 당전이 효율)

  • Hwang, Sung-Min;Seo, Seong-Hwa;Park, In-Myoung;Choi, Kyoung-Hwa;Kim, Do-Man;Cha, Jae-Ho
    • Microbiology and Biotechnology Letters
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    • v.40 no.2
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    • pp.104-110
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    • 2012
  • Glycosynthase is an active site nucleophile mutant enzyme, prepared from glycosidase, which is capable of synthesizing oligosaccharide derivatives without the hydrolysis of the product. Thermoacidophilic ${\alpha}$-glucosidase of Thermoplasma acidophilum (AglA) exhibits a transglycosylating activity yielding various glycosides. AglA was converted to glycosynthase by the substitution of the catalytic nucleophile Asp-408 residue into non-nucleophile glycine in order to increase its ability to synthesize various glycosides by transglycosylation. The glycosynthase mutant was purified by Ni-NTA chromatography and its glycoside-synthesizing activity was measured by using an external nucleophile, sodium formate buffer, providing maltose as a donor and p-nitrophenyl-${\alpha}$-D-glucopyranoside ($pNP{\alpha}G$) as an acceptor, respectively. In addition, $pNP{\alpha}G$ was examined for its feasibility to act as both a donor and an acceptor, and products were compared with those of the wildtype enzyme. The mutant enzyme was found to catalyze the formation of a specific product from $pNP{\alpha}G$ with a yield of 42.5% without further hydrolysis, while the wild-type enzyme produced two $pNP{\alpha}G$ products at low yields. The results demonstrate the possibility of satisfactory yields for the reactions in the presence of small amounts of acceptor, and demonstrate that the high activity of the mutant, at pHs below neutrality, was applicable in the transfer of glucose from the natural donor.

Surface Acting, Emotion Exhaustion and Turnover Intention: Moderating Roles of Social Support (서비스기업 종업원의 표면행위가 이직의도에 미치는 영향에 관한 연구: 지각된 사회적 지원의 조절효과를 중심으로)

  • Kim, Wan-Min;Kang, Seong-Ho;Lee, Han-Geun
    • Journal of Distribution Science
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    • v.15 no.2
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    • pp.101-109
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    • 2017
  • Purpose - Previous studies related to emotional labor of salespeople have mainly focused on identifying the antecedents of emotional exhaustion and turnover intention and exploring the mitigating effects salespeople's motivation on emotional exhaustion and turnover intention. They also demonstrates that there are different roles for moderating in social support, which means mental/physical support related to the job in supervisors, colleagues and organizations. The purpose of this paper is to investigate how service employees' surface acting affect turnover intention through emotional exhaustion. Another important objective of this paper is to investigate whether perceived social support moderates 1) the relationship between surface acting and emotional exhaustion 2) the relationship between emotional exhaustion and turnover intention. Research design, data, and methodology - To test the hypotheses, we collected the data from Korean insurance company sales employees. A total of 235 responses were received, from which 220 usable responses were obtained after list-wise deletion. Working with a sample of 220 responses, structural equation modeling was employed to empirically test research hypotheses(

    The relationship between surface acting and emotion exhaustion,

    The relationship between emotion exhaustion and turnover intention,

    The moderating effect of perceived social support(PSS) on the relationship between surface acting and emotion exhaustion, and

    The moderating effect of perceived social support(PSS) on the relationship between emotion exhaustion and turnover intention. SPSS 22.0 and AMOS software were used in these data analysis. Results - The service employees' surface acting was positively related to the emotional exhaustion; in turn, the service employees' feelings on emotional exhaustion are positively related to turnover intention. In addition, Perceived Social Support significantly moderated the relationship between surface acting and emotional exhaustion. However, perceived social support has a non-significant moderating effect on the path from emotional exhaustion to turnover intention. On the basis of these results, the following conclusion can be drawn. First, distribution service companies will be needed the administrative efforts to offer counseling programs and space to provide their members with enough rest in experiencing psychological pain due to the salespeople's surface acting. Also, it is necessary for distribution service companies to identify and share the examples of successfully solving emotional exhaustion caused by salespeople's surface acting.

Analysis on the Shear Behavior of Existing Reinforced Concrete Frame Structures Infilled with L-Type Precast Wall Panel (L형 프리캐스트 콘크리트 벽패널로 채운 기존 철근 콘크리트 골조 구조물의 전단 거동 분석)

  • Yu, Sung-Yong;Ju, Ho-Seong;Ha, Soo-Kyoung
    • Journal of the Korean Society for Advanced Composite Structures
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    • v.6 no.2
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    • pp.105-117
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    • 2015
  • The purpose of this study is to develop a new seismic resistant method by using precast concrete wall panels for existing low-rise, reinforced concrete beam-column buildings such as school buildings. Three quasi-static hysteresis loading tests were experimentally performed on one unreinforced beam-column specimen and two reinforced specimens with L-type precast wall panels. The results were analyzed to find that the specimen with anchored connection experienced shear failure, while the other specimen with steel plate connection principally manifested flexural failure. The ultimate strength of the specimens was determined to be the weaker of the shear strength of top connection and flexural strength at the critical section of precast panel. In this setup of L-type panel specimens, if a push loading is applied to the reinforced concrete column on one side and push the precast concrete panel, a pull loading from upper shear connection is to be applied to the other side of the top shear connection of precast panel. Since the composite flexural behavior of the two members govern the total behavior during the push loading process, the ultimate horizontal resistance of this specimen was not directly influenced by shear strength at the top connection of precast panel. However, the RC column and PC wall panel member mainly exhibited non-composite behavior during the pull loading process. The ultimate horizontal resistance was directly influenced by the shear strength of top connection because the pull loading from the beam applied directly to the upper shear connection. The analytical result for the internal shear resistance at the connection pursuant to the anchor shear design of ACI 318M-11 Appendix-D except for the equation to predict the concrete breakout failure strength at the concrete side, principally agreed with the experimental result based on the elastic analysis of Midas-Zen by using the largest loading from experiment.

Analysis of Development and Application of Pattern Identification System -Based on Oriental Obesity Pattern Identification- (변증 진단 체계 개발 및 응용 연구 분석 -한방 비만변증을 중심으로-)

  • Park, Jung-Sik;Song, Yun-Kyung;Hwang, Eui-Hyoung;Chung, Won-Suk;Park, Won-Hyung;Cha, Yun-Yeop;Shin, Seung-Woo;Park, Tae-Yong;Jang, Bo-Hyoung;Kim, Ho-Jun;Ko, Seong-Gyu
    • Journal of Korean Medicine Rehabilitation
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    • v.24 no.2
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    • pp.107-114
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    • 2014
  • Objectives The purpose of this study is analyzing internal research trends of oriental obesity pattern identification in korean literature based on obesity pattern identification questionnaires, development and application of Pattern Identification System to help solve problems of future researches. Methods 6 Korean databases were searched for articles of oriental obesity pattern identification, irrespective of publication year and 13 studies were reviewed. An analytical method such as descriptive statistics and an actual number and percentage was used. Results We collected 13 studies. 4 studies were published in 2012 and 2008, the highest number of studies. 7 Clinical studies were the major research method. The Studies were classified according to the characteristics and design. 5 studies were about research of analysis and improvement of oriental obesity pattern identification questionnaire, the most number of studies. 4 studies were about research of observational studies in clinical on obesity pattern identification. 3 studies were about research of intervention studies in clinical on obesity pattern identification and 1 study was about clinical practice recommendation. Conclusions Establishment of obesity pattern identification system and its clinical application could lead to standardizing obesity pattern identification and clinical practice guideline. Applied on other diseases, obesity pattern identification system could also lead to improving treatment rate, contributing to the development of clinical practice guidelines and academic field of research.

Influences of Silkworm Sericin on the Improvement Actions of Lipid Metabolism in Dyslipidemic Rats (실크 세리신이 이상지질혈증 흰쥐의 지질대사 개선작용에 미치는 영향)

  • Kim, Han-Soo;Seong, Jong-Hwan;Lee, Young-Guen;Yoon, Ho-Dong;Kang, Jin-Soon;Xie, Cheng-Liang;Shin, Ji-Moon
    • Journal of Life Science
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    • v.20 no.10
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    • pp.1525-1531
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    • 2010
  • The principal objective of this study was to investigate the effects of silkworm sericin extract supplementation on the improvement of lipid compositions, blood glucose levels and enzyme activities in the serum of dyslipidemic rats. The rats were fed the experimental diet for 5 weeks. Concentrations of total cholesterol, atherosclerotic index, LDL-cholesterol, triglyceride (TG), phospholipid (PL), free cholesterol, cholesteryl ester ratio and blood glucose in serum were higher in the dyslipidemic group (group HCW) and cholesterol-plus-silkworm sericin extract intake group (group HCS) than those in the control group (group BW, basal diet-plus-water). However, the concentrations of total cholesterol, atherosclerotic index, LDL-cholesterol, TG, PL, free cholesterol, cholesteryl ester ratio and blood glucose level in serum were lower in group HCS than those in group HCW. On the other hand, the HDL-cholesterol level and the ratio of HDL-cholesterol to total cholesterol in group HCS were higher than in group HCW. The activities of alkaline phosphatase (ALP) and aminotransferase (AST & ALT) in serum were lower in group HCS than in the dyslipidemic group HCW. From the above results, it was suggested that silkworm sericin extract intake was effective in the prevention and improvement of lipid components, blood glucose level and enzyme activities in the sera of dyslipidemic rats.

A Preliminary Geomorphic Overview of Late Quaternary Glacier Fluctuations in the South Shetland Islands, West Antarctica (서남극 남쉐틀랜드 군도의 제4기 후기 빙하 활동의 지형학적 고찰)

  • Lim, Hyoun-Soo;Yoon, Ho-Il;Lee, Yong-Il;Kim, Yea-Dong;Owen Lewis A.;Seong, Yeong-Bae
    • Journal of the Korean Geographical Society
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    • v.41 no.5 s.116
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    • pp.513-526
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    • 2006
  • The timing and extent of glaciations during the Late Quaternary in the South Shetland Islands, West Antarctica were defined using field mapping, geomorphic analysis and radiocarbon dating. Landforms of glacial erosion and deposition, in particular subglacial meltwater channel erosion, suggest that at least three glaciations occurred during the late Quaternary within the study region. During the global LGM, glacial troughs (such as Maxwell Bay and Admiralty Bay) were overdeepened by an ice stream moving south from $an\sim1000m-thick$ ice cap centered on the present-day continental shelf to the north. This ice was responsible for the subglacial meltwater channel erosion, and glacial polished and striated bedrock on the Fildes Peninsula. The recent local glaciations occurred about 2,000 years ago and during Little Ice Age (LIA). During these glaciations, glaciers were less extensive than the previous one and less erosive as a cold-based ice

MECHANICAL PROPERTIES OF TITANIUM CONNECTORS TREATED BY VARIOUS WELDING TECHNIQUES (용접방법에 의한 타이타늄 연결부의 기계적 성질에 관한 연구)

  • Lee, Soo-Young;Chang, Ik-Tae;Heo, Seong-Joo;Yim, Soon-Ho
    • The Journal of Korean Academy of Prosthodontics
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    • v.37 no.5
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    • pp.545-566
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    • 1999
  • The use of pure titanium and titanium alloys have been increased recently in fixed, removable prosthodontics and implant fields as a framework. But when they were used for superstructures of implant or metal framework of removable prosthesis, welding is necessary to reconnect the fracture site to control the casting distortions. To overcome the difficulties in soldering the titanium due to high oxidation property, much effort have been devoted. In this study, some of mechanical properties were compared between pure titanium and Ti-6Al-4V alloy by using after welding, electron beam welding technique and tungsten arc welding. Mechanical properties such as tensile strength, yield strength, elongation and microhardness were measured. And, in order to compare the effect of welding site and surrounding metal tissue according to the welding condition, SEM photographs were taken and element distribution was observed by Wave Dispersion Spectroscopy. Through analyses of the data, following results were obtained; 1. In items such as tensile strength, yield strength and elongation according to the welding techniques of pure titanium, only tungsten arc welded group showed significant lower value than other groups(P<0.05). 2. In items such as tensile strength and yield strength according to the welding techniques of Ti-6Al-4V alloy, control group and tungsten arc welded group showed significant difference among all the groups(P<0.05). 3. Ti-6Al-4V alloy exhibited significantly greater elongation than control group when the laser welding method and electron beam welding method were used, and elongation showed increasing tendency. 4. Pure titanium specimens exhibited increasing tendency of microhardness regardless of the weld-ing technique applied, and especially tungsten arc welded group demonstrated a great increase of microhardness than parent metal. 5. There was no hardness change in laser welded group and electron beam welded group of Ti-6Al-4V alloy, but in tungsten arc welded group, hardness changed greatly from parent metal to weld seam. 6. Through the metallographic examination and scanning electron microscopy, laser welding caused central fusion and recristallizations were formed and tungsten arc welding caused localized fusion to 0.3-0.7mm from the surface.

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