• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.9 s.112
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• pp.811-820
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• 2006

Ultra wideband CPW batons are proposed in this paper. The proposed talons are consisted of ultra wideband multi-stage Wilkinson dividers and 'X'-shaped $180^{\circ}$ out-of-phase generator. Bottom-bridges and via-holes are used to connect CPW ground lines instead of the conventional air-bridges which require troublesome manual working in fabrication with HMIC(Hybrid Microwave Integrated Circuits) substrates. The proposed CPW batons have ultra wideband of 3 or $10(=F_{figh}/F_{low})$ theoretically, the wideband characteristics and S-parameters of the basis Wilkinson divider are directly converted to those of the proposed batons. The proposed batons are so compact and small compared to the conventional Wilkinson batons because no additional area for out-of-phase section is required. So the size of the proposed batons is exactly the same as that of the basis Wilkinson dividers. As examples, 3-stage and 7-stage wideband Wilkinson dividers are converted to the proposed batons. Their measured operating bandwidth are $1\sim3GHz$ and $0.8\sim5GHz$, respectively, with excellent matching, isolation and power division performances. The measured magnitude and phase balance errors are ${\pm}0.5dB\;and\;0.45\;dB,\;and\;{\pm}5^{\circ}\;and\;{\pm}10^{\circ}C$ over $1\sim3GHz\;and\;0.8\sim5GHz$, respectively.

• The Journal of Korean Society for Radiation Therapy
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• v.14 no.1
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• pp.175-186
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• 2002

The purpose of this study is directly measure and evaluate about absorbed dose change according to nominal energy and electron cone or medical accelerator on isodose curve, percentage depth dose, contaminated X-ray, inhomogeneous tissue, oblique surface and irradiation on intracavitary that electron beam with high energy distributed in tissue, and it settled standard data of hish energy electron beam treatment, and offer to exactly data for new dote distribution modeling study based on experimental resuls and theory. Electron beam with hish energy of $6{\sim}20$ MeV is used that generated from medical linear accelerator (Clinac 2100C/D, Varian) for the experiment, andwater phantom and Farmer chamber md Markus chamber und for absorbe d dose measurement of electron beam, and standard absorbed dose is calculated by standard measurements of International Atomic Energy Agency(IAEA) TRS 277. Dose analyzer (700i dose distribution analyzer, Wellhofer), film (X-OmatV, Kodak), external cone, intracavitary cone, cork, animal compact bone and air were used for don distribution measurement. As the results of absorbed dose ratio increased while irradiation field was increased, it appeared maximum at some irradiation field size and decreased though irradiation field size was more increased, and it decreased greatly while energy of electron beam was increased, and scattered dose on wall of electron cone was the cause. In percentage depth dose curve of electron beam, Effective depth dose(R80) for nominal energy of 6, 9, 12, 16 and 20 MeV are 1.85, 2.93, 4.07, 5.37 and 6.53 cm respectively, which seems to be one third of electron beam energy (MeV). Contaminated X-ray was generated from interaction between electron beam with high energy and material, and it was about $0.3{\sim}2.3\%$ of maximum dose and increased with increasing energy. Change of depth dose ratio of electron beam was compared with theory by Monte Carlo simulation, and calculation and measured value by Pencil beam model reciprocally, and percentage depth dose and measured value by Pencil beam were agreed almost, however, there were a little lack on build up area and error increased in pendulum and multi treatment since there was no contaminated X-ray part. Percentage depth dose calculated by Monte Carlo simulation appeared to be less from all part except maximum dose area from the curve. The change of percentage depth dose by inhomogeneous tissue, maximum range after penetration the 1 cm bone was moved 1 cm toward to surface then polystyrene phantom. In case of 1 cm and 2 cm cork, it was moved 0.5 cm and 1 cm toward to depth, respectively. In case of air, practical range was extended toward depth without energy loss. Irradiation on intracavitary is using straight and beveled type cones of 2.5, 3.0, 3.5 $cm{\phi}$, and maximum and effective $80\%$ dose depth increases while electron beam energy and size of electron cone increase. In case of contaminated X-ray, as the energy increase, straight type cones were more highly appeared then beveled type. The output factor of intracavitary small field electron cone was $15{\sim}86\%$ of standard external electron cone($15{\times}15cm^2$) and straight type was slightly higher then beveled type.

• Journal of Chest Surgery
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• v.10 no.1
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• pp.98-105
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• 1977

A 36 year old blindman, engineer was admitted with chief complaints of hemoptysis, recurrent sore throat, pyoderma in genital organ, uveitis and thrombophlebitis for 10 years. Above the chief complaints were remission or exacerbation during hospitalization. Physicalexamination showed that left radial, ulnar & brachial pulse was not palpable. No bruit or murmur was obtained over the mass. Neurologic examination revealed no significant finding.On admission, chest P-A showed hen egg sized round & oval compact hazy density on left upper lung field. Bronchogram revealed no pathological finding and Lt. tomogram showed well define large,ovoid mass density in the superior mediastinum. Fluoroscopy finding showed nonpulsatile on left upper lung field. Pre-op. aortography was not taken, under the impression of lung Ca. rule out .sortie aneurysm, exploratory operation was performed through the 2nd intercostal space, Lt. It was performed that the mass was ascending sortie aneurysm of saccular type. Direct aneurysmectomy with multiple figure of eight suture were done without any prosthetic graft. Post-op. control I.V.C graphy showed completely obstruction sign. Postopcontrol aortography revealed good surgical result. Final, histopathological answered non-specific sortie aneurysm, saccular type. Post-op. courses were uneventful except mild neurologic disturbance with subclavian steal syndrome and associated with both lower leg pitting edema due to inferior vena cava obstruction. After op, 3 month later, discharged to home, with big systemic problem. Behcet`s syndrome reviewed with related literatures. The coexistence of mouth and genital ulceration with hypopyon mentioned by hippocrates and described by various workers in the early part of this century was first defined as a syndrome by Behcet in 1937. In 1937 Behcet described a chronic relapsing triple symptom complex of oral ulceration, genital ulceration, and ocular inflammation. The place of the syndrome as part of a systemic disorder in now clearer, and the under lying pathology appears to be a vasculitis. The disease runs a- chronic course, blindness being the greatest disability and control nervous system involvement a cause of death. Thrombophlebitis is fairly frequent, france et al [1951] giving an incidence of 25% and Dowling [1961] 12%, superficial thrombophlebitis migrans and thrombosis of large veins, including venae cavae [Thomas, 1947: Boolukos 1960] are recorded. Little attention has been paid to arterial involvement. Mishima et al. [1961] described resection cf an aortic aneurysm in a 38 year old man with Behcet`s syndorme. Mounsey in a clinicopathological conference described a case [Brit, med. J., 1966] of ruptured aortic aneurysm in Bechcet`s syndrome treated by aorto-iliac graft. Also, Shikano and Oshima et al [1963] recorded two aneyrysm of smaller arteries. Unfrequently, aortic aneurysm was presumed to be secondary to osteomyelitis of the lumber spine, though the possible association between aortic aneurysm and Behcet`s syndrome was raised. A further case is reported here, in which ascending aortic aneurysm with Behcet`s Ds. appeared to form part of this generalized disease. This is a case report of surgical experience of Behcet`s Ds. with ascending aortic aneurysm which had nearly all the typical clinical features. Above mentioned and was reviewed with related literatures.

• Food Science and Preservation
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• v.19 no.1
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• pp.19-25
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• 2012

An experiment was conducted to find out the effect of brushing treatment during cultivation on the postharvest quality of the baby leaf vegetable, specifically tah tasai Chinese cabbage (Brassica campestris var. narinosa). The effect of mechanical brushing during cultivation on the postharvest quality was determined in terms of the quality changes in weight loss, gas partial pressure, leaf color, and appearance during storage using a 30-${\mu}m$-thick polypropylene film at $16^{\circ}C$. The brushing treatment included brushing with A4 paper back and forth 50 times a day. The study revealed that the growths on the brushing-treated plant group were less than those on the control group. The structure of the leaf tissue of the brushing-treated plant also tended to be less compact than that of the non-treated plant. The brushing treatment resulted in less growth and denser plant tissues as well as in differences in the gas $O_2$ consumption and $CO_2$ accumulation after packaging. For the gas partial pressure, the $O_2$ consumption and $CO_2$ accumulation of the brushing-treated plant tended to be less than those of the non-treated plant. There were no differences, however, between the brushing-treated plant and control groups in the SPAD value and appearance. The study results also suggested that after packaging, the effects of the brushing treatment during cultivation on the quality of the tah tasai Chinese cabbage baby leaf vegetable was not significant. As such, it is recommended that effective post-harvest methods of improving the product quality of the baby leaf vegetable be further investigated.

• Journal of Technologic Dentistry
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• v.30 no.1
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• pp.25-31
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• 2008

Cp-Ti and Ti-6Al-4V alloys commonly used dental implant materials, particularly for orthopaedic and osteosynthesis because of its suitable mechanical properties and excellent biocompatibility. This alloys have excellent corrosion behavior in the clinical environment. The first factor to decide the success of dental implantation is sufficient osseointegration and high corrosion resistance between on implant fixture and its surrounding bone tissue. In this study, in order to increase corrosion resistance and biocompatibility of Cp-Ti and Ti-6Al-4V alloy that surface of manufactured alloy was coated with TiN by RF-magnetron sputtering method. The electrochemical behavior of TiN coated Cp-Ti and Ti-6Al-4V alloy were investigated using potentiodynamic (EG&G Co, PARSTAT 2273. USA) and potentiostatic test (250mV) in 0.9% NaCl solution at 36.5 $\pm$ 1$^{\circ}C$. These results are as follows : 1. From the microstructure analysis, Cp-Ti showed the acicular structure of $\alpha$-phase and Ti-6Al-4V showed the micro-acicular structure of ${\alpha}+{\beta}$ phase. 2. From the potentiodynamic test, Ecorr value of Cp-Ti and Ti-6Al-4V alloys showed -702.48mV and -319.87mV, respectively. Ti-6Al-4V alloy value was higher than Cp-Ti alloy. 3. From the analysis of TiN and coated layer, TIN coated surface showed columnar structure with 800 nm thickness. 4. The corrosion resistance of TiN coated Cp-Ti and Ti-6Al-4V alloys were higher than those of the non-coated Ti alloys in 0.9% NaCl solution from potentiodynamic test, indicating better protective effect. 5. The passivation current density of TiN coated Cp-Ti and Ti-6Al-4V alloys were smaller than that of the noncoated implant fixture in 0.9% NaCl solution, indicating the good protective effect resulting from more compact and homogeneous layer formation.

• Nuclear Engineering and Technology
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• v.47 no.4
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• pp.479-487
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• 2015

The thallium-doped sodium iodide [NaI(Tl)] scintillation detector is preferred as a gamma spectrometer in many fields because of its general advantages. A silicon photomultiplier (SiPM) has recently been developed and its application area has been expanded as an alternative to photomultiplier tubes (PMTs). It has merits such as a low operating voltage, compact size, cheap production cost, and magnetic resonance compatibility. In this study, an array of SiPMs is used to develop an NaI(Tl) gamma spectrometer. To maintain detection efficiency, a commercial NaI(Tl) $2^{\prime}{\times}2^{\prime}$ scintillator is used, and a light guide is used for the transport and collection of generated photons from the scintillator to the SiPMs without loss. The test light guides were fabricated with polymethyl methacrylate and reflective materials. The gamma spectrometer systems were set up and included light guides. Through a series of measurements, the characteristics of the light guides and the proposed gamma spectrometer were evaluated. Simulation of the light collection was accomplished using the DETECT 97 code (A. Levin, E. Hoskinson, and C. Moison, University of Michigan, USA) to analyze the measurement results. The system, which included SiPMs and the light guide, achieved 14.11% full width at half maximum energy resolution at 662 keV.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.2
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• pp.174-183
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• 2001

During the rapid phase of gonadal development of the freshwater teleost, the catfish (Silurus asotus), the influence of hCG upon the inducement of final oocyte maturation and spawning was investigated electrophoretically and ultrastructurally. The electrophoretic patterns obtained were different in the presence and absence of some of the major or minor zones, because of the hormone level in catfish. The vitellogenin of hormone-treated fish was stained more intensively than that of sham-treated fish. These proteins showed some minor or main bands of egg extracts which migrated at positions corresponding to molecular weights of approximately 90,000. However, the thickness of electrophoretic band in molecular weight for hCG-treated fish was slightly lower than that for saline control. It seemed the plasma protein with molecular weight of approximately 45,000 in hCG-treated fish disappeared. In contrast to the control fish, the ovaries in the catfish treated with hCG shows a marked ultrastructural change under the electron microscope. No dilated profiles were seen in the granulosa cells of the mature oocyte before ovulation. After germinal vesicle breakdown (GVBD), the zona radiata interna (ZRI) becomes more compact, and there is a loss of all the processes from the pore canals. There is a wide space between the vitelline membrane and zona radiata. Also, during final maturation, the microvillar processes from the oocyte are seen no longer to penetrate deeply into the extracellular spaces of the overlying granulosa cells, and the reticulate patterns of the zona radiata interna becomes occluded, giving the zona radiata a more solid appearance. It has been possible to initiate 100% oocyte maturation in yolk granules and follicles in vivo by treatment with hCG and a high water temperature ($27^{\circ}C$). In hCG-treated fish, the percentages of successful artificial fertilization and hatching were maximal at 15 h after a single injection. It seems clear that a long acting preparation containing hCG can be successfully used in prespawning fish to advance the final events of gonadal maturation and initiate spawning. Further studies are necessary to evaluate the potential of hCG to either stimulate or inhibit the reproductive development of fish at other stages of the seasonal reproductive cycle.

• Journal of the Korean Society of Clothing and Textiles
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• v.16 no.2
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• pp.237-244
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• 1992

The purpose of this study was to comparatively evaluate thermal and water transmission properties of several vapor permeable water repellent (VPWR) fabrics and synthetic battings that became available in recent years. Five VPWR fabrics evaluated were Hipora in three coating variants, $Gore-Tex^{\circledR}$ and $Aitace^{\circledR}$. Battings evaluated were $Viwarma^{\circledR}$, $Uniwarmr^{\circledR}$, $Thinsulate^{\circledR}$, and $Airseal^{\circledR}$ Thermal resistance and water vapor transmission were measured for each fabric and batting and in all combinations. Thermal resistance at zero and 37 cm/sec air velocity was determined by the Thermo Labo II technique for simultaneously measuring conduction and radiation heat transfer. Water vapor transmission over 24 hours was measured by a modified weight-gain method in a compact humid chamber at conditions simulating the clothing climate under heavy exercise ($40{\pm}1^{\circ}C$, $90{\pm}2\%$ R.H., and 0.5 m/sec air velocity). Fabric porosity was calculated from fiber density and fabric weight, thickness, and area. Thermal resistance results for the fabrics showed the effectiveness of coatings in inhibiting heat transfer. Measurements taken in wind were: $31.1\~37.6\%$ for $Hipora^{\circledR}$ variants; $31.0\%$ for $Gore-Tex^{\circledR}$; and $18.4\%$ for $Aitaca^{\circledR}$ Measurements without wind were higher but in the same order. Water vapor transmission results were in reverse order: $Aitac^{\circledR}$, $8.8 kg/m^{2};\;Gore-Tex^{\circledR}$, 6.4 kg/$m^{2}$; and $Hipora^{\circledR},\;4.4\~6.0\;kg/m^{2}$. In general thermal resistance increased with porosity. For battings, the thermal resistance with wind results were: $Viwarmu^{\circledR}$, $65.0\%;\; Thinsulate^{\circledR}$, $62.0\%$; $Uniwarm^{\circledR}$, $61.0\%$; and $Airseala^{\circledR},\;53.1\%$. Thermal resistance was proportional to thickness. Thermal resistance of fabric-batting combinations were $20\%$ higher than those of the battings only. Water vapor transmission for combinations was mainly affected by that for the VPWR fabric used.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.52.2-52.2
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• 2014

The Immersion Grating Infrared Spectrometer (IGRINS) is an unprecedentedly minimized infrared cross-dispersed echelle spectrograph with a high-resolution and high-sensitivity optical performance. A silicon immersion grating features the instrument for the first time in this field. IGRINS will cover the entire portion of the wavelength range between 1.45 and $2.45{\mu}m$ accessible from the ground in a single exposure with spectral resolution of 40,000. Individual volume phase holographic (VPH) gratings serve as cross-dispersing elements for separate spectrograph arms covering the H and K bands. On the 2.7m Harlan J. Smith telescope at the McDonald Observatory, the slit size is $1^{\prime\prime}{\times}15^{\prime\prime}$. IGRINS has a $0.27^{\prime\prime}$ pixel-1 plate scale on a $2048{\times}2048$ pixel Teledyne Scientific & Imaging HAWAII-2RG detector with SIDECAR ASIC cryogenic controller. The instrument includes four subsystems; a calibration unit, an input relay optics module, a slit-viewing camera, and nearly identical H and K spectrograph modules. The use of a silicon immersion grating and a compact white pupil design allows the spectrograph collimated beam size to be 25mm, which permits the entire cryogenic system to be contained in a moderately sized rectangular vacuum chamber. The fabrication and assembly of the optical and mechanical hardware components were completed in 2013. In this presentation, we describe the major design characteristics of the instrument and the early performance estimated from the first light commissioning at the McDonald Observatory.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.2
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• pp.985-992
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• 2011

The 3D computational fluid dynamics (CFD) was performed in relation to the internal fluid characteristics and flow distribution for the development of the most optimal model in the complex post-disposal device. As it is expected that a channeling (drift) would be made by the semi-dry reactor due to the large difference in the flow distribution by the compartment in the bag filter, a structural improvement should be urgently made for more uniformed flow distribution in the bag filter. Three types of modifications such as i) changing the plenum shape, ii) orifice install in the exit part of cleaned gas, iii) increasing the plenum number were established. From the results of computational fluid dynamics, it was revealed that the changing of plenum shape and orifice install in the exit part of cleaned gas was more reasonable than the increasing the plenum number because of the difficulties of retrofit. The complex post-disposal device, modified and supplemented with this analysis, integrated the semi-dry reactor and the bag filter in a single body, so it follows that the improvement can make the device compact, save the installation area, save the operation fee, and management more convenient.