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The Roles of Gold Plate (140${\mu}{\textrm}{m}$) Loaded on TLD-100 Chips in the High Energy Radiation Beams (고에너지 광자선속에서 TLD-100 chip 위에 있는 금박막(140 ${\mu}{\textrm}{m}$) 역할)

  • Vahc, Young-Woo;Park, Kyung Ran.
    • Progress in Medical Physics
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    • v.6 no.2
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    • pp.51-60
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    • 1995
  • Lithium Fluoride (LiF; TLD-100) crystal chips are normally used as thermolu minescence dosimeters (abbreviated as NC-100) for estimating the absorbed dose to the skin of a patient or in a solid water phantom undergoing radiotherapy with megavoltage photon (6 and 15MV) beams. In general, investigation has revealed a reduction in the sensitivity of NC-100 chips after many runs through heating cycles. A TLD-100 chip laminated with gold plate (140${\mu}{\textrm}{m}$) on the upper surface layer of its face toward the photon beam (abbreviated as GC-100) has properties different from that of a NC-100 chip activated by incident photons and contaminant electrons with various lower energies coming from the gantry head and air. Activation of the valence band electrons of GC-100 chips by incident photons, positrons and electrons-which come from the gold plate by mainly pair production process and partly from Compton scattering-results in more enhanced signal intensity, higher response per monitor unit, as well as a good linearity with monitor units and independence of dose rate. Since the electron beams (6 and 15 MeV) do not have the probability of pair production process with gold plate, there is only a small difference (about a 3.3% increase for 15 MeV) in the signal gaps in the TL readout for electron beams between GC- and NC-100 chips. The 3.3% increase is entirely due to the buildup caused by the 140 m gold plate. The sensitivity of GC-100 chips is much more susceptible to high energy photon beams than electron one because of pair production. The interaction of high energy photon with a material of high atomic number, such as the good plate in this case, results in a considerably significant probability of pair production. The gold plate on the NC-100 chips acts as not only an intensifier of their signals but also acts as a filter of contaminant electrons in therapeutic high energy X-ray beams.

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Hydrogeneted Amorphous Carbon Nitride Films on Si(100) Deposited by DC Saddle Field Plasma Enhanced Chemical Vapor Deposition ($N_2/CH_4$가스비에 따른 Hydrogenated Amorphous Carbon Nitride 박막의 특성)

  • 장홍규;김근식;황보상우;이연승;황정남;유영조;김효근
    • Journal of the Korean Vacuum Society
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    • v.7 no.3
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    • pp.242-247
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    • 1998
  • Hydrogenated amorphous carbon nitride[a-C:H(N)] films were deposited on p-type Si(100) at room temperature with bias voltage of 200 V by DC saddle-field plasma-enhanced chemical vapor deposition. Effects of the ratio of $N_2$ to $CH_4$($N_2/CH_4$), in the range of 0 and 4 on such properties as optical properties, microstucture, relative fraction of nitrogen and carbon, etc. of the films have been investigated. The thickness of the a-C:H(N) film was abruptly decreased with the addition of nitrogen, but at $N_2/CH_4$>0.5, the thickness of the film gradually decreased with the increase of the $N_2/CH_4$. The ratio of N to C(N/C) of the films was saturated at 0.25 with the increase of $N_2CH_4$. N-H, C≡N bonds of the films increased but C-H bond decreased with the increase of $N_2CH_4$.Optical band gap energy of the film decreased from 2.53 eV at the ratio of $N_2CH_4$=4.

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Growth and Optical Properties of PbSnSe Epilayers Grown on BaF2(111) (PbSnSe 단결정 박막의 성장과 광학적 특성)

  • Lee, Il-Hoon
    • Journal of Korean Ophthalmic Optics Society
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    • v.9 no.1
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    • pp.35-41
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    • 2004
  • This study investigated the crystal growth, crystalline structure and the basic optical properties of $PbSnSe/BaF_2$ epilayers. The PbSnSe epilayer was grown on $BaF_2$(111) insulating substrates using a hot wall epitaxy (HWE) technique. It was found from the analysis of X-ray diffraction patterns that $PbSnSe/BaF_2$ epilayer was grown single crystal with a rock-salt structure oriented along [111] the growth direction. Using Rutherford back scattering, the atomic ratios of the PbSnSe was found to be proper stoichiometric. The best values for the full width at half maximum (FWHM) of the DCXRD was 162 arcsec for PbSnSe epilayer. The epilayer-thickness dependence of the FWHM of the DCXRD shows that the quality of the $PbSnSe/BaF_2$ is as expected. The dielectric function ${\varepsilon}(E)$ of a semiconductor is closely related to its electronic energy band structure and such relation can be drawn from features around the critical points(CPs) in the optical spectra. The real and imaginary parts(${\varepsilon}1$ and ${\varepsilon}2$) of the dielectric function ${\varepsilon}$ of PbSe were measured, and the observed spectra reveal distinct structures at energies of the E1, E2 and E3 CPs. These data are analyzed using a theoretical model known as the model dielectric function (MDF). The optical constants related to dielectric function such as the complex refractive index ($n^*=n+ik$), absorption coefficient (${\alpha}$) and normal-incidence reflectivity (R) are also presented for $PbSnSe/BaF_2$.

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The effects of the correction exercise program combined with stretching and elastic band exercise on femoral intercondylar distance, Q-angle, plantar pressure in undergraduate with genu varum (탄성밴드운동과 스트레칭을 이용한 교정운동프로그램이 내반슬 대학생들의 무릎간 간격, Q-각 및 족압의 변화에 미치는 영향)

  • Yu, Byong-Kyu;Kim, Eun-Hye
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.3
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    • pp.2064-2072
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    • 2015
  • The aim of this study is to identify the effects of the correction exercise program on femoral intercondylar distance, Q-angle and plantar pressure in undergraduate with genu varum. A experimental study with a randomized controlled trial design was used. Thirty subjects with genu varum were allocated in two groups: the experimental group (n=15) or the control group (n=15). The experimental group conducted correction exercise program for 30 minutes a day, 5 times a week, for 6 weeks, while the control group did not perform any exercise. The correction exercise program group showed a significant decreased femoral intercondylar distance, plantar pressure of M 4, M 5 (Metatarsal 4, 5). Also the correction exercise program group significantly increased Q-angle, plantar pressure of Toe 2-5 and M 1, M 2, M 3 (Metatarsal 1, 2, 3) (Rt, Lt) (p<.05). Thus, we suggested that the correction exercise program may be suitable intervention to improve normal alignment in undergraduate with genu varum.

A Red Ginseng Internal Measurement System Using Back-Projection (Back-Projection을 활용한 홍삼 내부 측정 시스템)

  • Park, Jaeyoung;Lee, Sangjoon
    • KIPS Transactions on Software and Data Engineering
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    • v.7 no.10
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    • pp.377-382
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    • 2018
  • This study deals with internal state and tissue density analysis methods for red ginseng grade determination. For internal measurement of red ginseng, there have been various studies on nondestructive testing methods since the 1990s, It was difficult to grasp the most important inner hole and inside whites in the grading. So in this study, we developed a closed capturing device for infra-red illumination environment, and developed an internal measurement system that can detect the presence and diameter of inner hole and inside whites. Made devices consisted of infrared lights with a high transmission rate of red ginseng in 920 nanometer wave band, a infra-red camera and a Y axis actuator with a red ginseng automatically controlled focus on the camera. The proposed algorithm performs an auto-focus system on the Y-axis actuator to automatically adjust the sharp focus of the object according to the size and thickness. Then red ginseng is rotated $360^{\circ}$ at $1^{\circ}$ intervals and 360 total images are acquired, and reconstructed as a sinogram through Radon transform and Back-projection algorithm was performed to acquire internal images of red ginseng. As a result of the algorithm, it was possible to acquire internal cross-sectional image regardless of the thickness and shape of red ginseng. In the future, if more than 10,000 different shapes and sizes of red ginseng internal cross-sectional image are acquired and the classification criterion is applied, it can be used as a reliable automated ginseng grade automatic measurement method.

The Analysis of Evergreen Tree Area Using UAV-based Vegetation Index (UAV 기반 식생지수를 활용한 상록수 분포면적 분석)

  • Lee, Geun-Sang
    • Journal of Cadastre & Land InformatiX
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    • v.47 no.1
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    • pp.15-26
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    • 2017
  • The decrease of green space according to the urbanization has caused many environmental problems as the destruction of habitat, air pollution, heat island effect. With interest growing in natural view recently, proper management of evergreen tree which is lived even the winter season has been on the rise importantly. This study analyzed the distribution area of evergreen tree using vegetation index based on unmanned aerial vehicle (UAV). Firstly, RGB and NIR+RG camera were loaded in fixed-wing UAV and image mosaic was achieved using GCPs based on Pix4d SW. And normalized differences vegetation index (NDVI) and soil adjusted vegetation index (SAVI) was calculated by band math function from acquired ortho mosaic image. validation points were applied to evaluate accuracy of the distribution of evergreen tree for each range value and analysis showed that kappa coefficient marked the highest as 0.822 and 0.816 respectively in "NDVI > 0.5" and "SAVI > 0.7". The area of evergreen tree in "NDVI > 0.5" and "SAVI > 0.7" was $11,824m^2$ and $15,648m^2$ respectively, that was ratio of 4.8% and 6.3% compared to total area. It was judged that UAV could supply the latest and high resolution information to vegetation works as urban environment, air pollution, climate change, and heat island effect.

The Effect of Thermal Annealing and Growth of Cdln2S4 Single Crystal Thin Film by Hot Wall Epitaxy (Hot Wall Epitaxy(HWE)법에 의한 Cdln2S4 단결정 박막 성장과 열처리 효과)

  • 홍광준;이관교
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.15 no.11
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    • pp.923-932
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    • 2002
  • A stoichiometric mixture of evaporating materials for CdIn$\_$2/S$\_$4/ single crystal thin films was prepared from horizontal furnace. To obtain the single crystal thin films, CdIn$\_$2/S$\_$4/ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by hot wall epitaxy(HWE) system. The source and substrate temperatures were 630 $\^{C}$ and 420 $\^{C}$, respectively. The crystalline structure of single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction(DCXD). The carrier density and mobility of CdIn$\_$2/S$\_$4/ single crystal thin films measured from Hall effect by van der Pauw method are 9.01$\times$10$\^$16/ cm$\^$-3/ and 219 ㎠/V$.$s at 293 K, respectively. From the optical absorption measurement, the temperature dependence of energy band gap on CdIn$\_$2/S$\_$4/ single crystal thin films was found to be Eg(T) = 2.7116 eV - (7.74 $\times$ 10$\^$-4/ eV) T$\^$2//(T+434). After the as-grown CdIn$\_$2/S$\_$4/ single crystal thin films was annealed in Cd-, S-, and In-atmospheres, the origin of point defects of CdIn$\_$2/S$\_$4/ single crystal thin films has been investigated by the photoluminescence(PL) at 10 K. The native defects of V$\_$cd/, V$\_$s/, Cd$\_$int/ and S$\_$int/ obtained by PL measurements were classified as donors or accepters type. And we concluded that the heat-treatment in the S-atmosphere converted CdIn$\_$2/S$\_$4/ single crystal thin films to an optical p-type. Also, we confirmed that In in CdIn$\_$2/S$\_$4/GaAs did not from the native defects because In in CdIn$\_$2/S$\_$4/ single crystal thin films existed in the form of stable bonds.

The Effect of Thermal Annealing and Growth of CdGa2Se4 Single Crystal Thin Film by Hot Wall Epitaxy (Hot Wall Epitaxy(HWE)법에 의한 CdGa2Se4 단결정 박막 성장과 열처리 효과)

  • Hong, Myung-Seok;Hong, Kwang-Joon
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.20 no.10
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    • pp.829-838
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    • 2007
  • The stochiometric mix of evaporating materials for the $CdGa_2Se_4$ single crystal thin films was prepared from horizontal furnace. To obtain the single crystal thin films, $CdGa_2Se_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperature were $630^{\circ}C$ and $420^{\circ}C$, respectively. The crystalline structure of single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD).The carrier density and mobility of $CdGa_2Se_4$ single crystal thin films measured from Hall effect by van der Pauw method are $8.27{\times}10^{17}\;cm^{-3},\;345\;cm^2/V{\cdot}s$ at 293 K. respectively. The temperature dependence of the energy band gap of the $CdGa_2Se_4$ obtained from the absorption spectra was well described by the Varshni's relation, $Eg(T)\;=\;2.6400\;eV\;-\;(7.721{\times}10^{-4}\;eV/K)T^2/(T+399\;K)$. After the as-grown single crystal $CdGa_2Se_4$ thin films were annealed in Cd-, Se-, and Ga -atmospheres, the origin of point defects of single crystal $CdGa_2Se_4$ thin films has been investigated by PL at 10 K. The native defects of $V_{Cd}$, $V_{Se}$, $Cd_{int}$, and $Se_{int}$ obtained by PL measurements were classified as donors or accepters. We concluded that the heat-treatment in the Cd-atmosphere converted single crystal $CdGa_2Se_4$ thin films to an optical p-type. Also, we confirmed that Ga in $CdGa_2Se_4/GaAs$ did not form the native defects because Ga in single crystal $CdGa_2Se_4$ thin films existed in the form of stable bonds.

Aneurysmal Bone Cyst of the Rib Misdiagnosed as Soft Tissue Tumor - A Case Report - (연부조직종괴로 오인된 늑골의 동맥류성 골낭종 - 증례 보고 -)

  • Lee, Ah-Won;Lee, Youn-Soo;Jo, Gun-Huyn;Lee, Jung-Dal;Kim, Byung-Kee
    • The Journal of the Korean bone and joint tumor society
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    • v.6 no.4
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    • pp.163-167
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    • 2000
  • Aneurysmal bone cyst(ABC) is a benign lesion and generally occurs in the long bones and vertebral column. ABC of the rib is an uncommon entity. We reported a case of ABC originating in the left first rib. The patient was a 19-year-old woman and presented with palpable mass on the shoulder. Chest X ray and MRI showed a large expansile mass, with multiple cystic areas, arising from the left first rib and bulging out into retroclavicular and paravertebral soft tissue, so the lesion was initially misdiagnosed as a soft tissue malignant tumor destructing adjacent rib. On histological examination, the mass, which was surrounded by a peripheral band of mature trabecular bone, consisted of multiple anastomosing cavernous blood channels separated by fibrous septa that containing osteoid, myxochondroid material and osteoclast-type giant cells.

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Acupuncture, ST-36 Electroacupuncture and Moxa Treatment of Abdominal Pain due to Bowel Obstruction in Cancer Patients : Case Report (말기 암 환자의 장폐색성 복통에 대한 침구 및 족삼리 전침 치험 2례)

  • Kim, So Yeon;Choi, Jun Yong;Park, Seong Ha;Kwon, Jung Nam;Lee, In;Hong, Jin Woo;Han, Chang Woo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.28 no.2
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    • pp.238-242
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    • 2014
  • Here we described 2 cancer patients treated by acupuncture for abdominal pain as a complication of bowel obstruction. The patient 1, 43-year-old man was treated with surgery, radiotherapy and chemotherapy for rectal cancer. Two years after surgery, he complained of acute abdominal pain due to small bowel adhesion band. Bowel obstruction and symptoms were not improved by conservative therapy like as fasting, keeping Levin tube, and fluid therapy. 4 months later, he could eat a little rice water, but ileus and abdominal pain persisted despite of applying opiod drug and patch. Got started on acupuncture, electroacupuncture(ST-36) and moxa treatment, pain was relived gradually. He could stop opioids 1 month later and ileus was improved after acupuncture therapy for 2 months. The patient 2, 65-year-old woman got hepatectomy, cholecystectomy, and chemotherapy with cholangiocarcinoma. 6 months after surgery, she got laparotomy again for biopsy of new mass around ascending colon. She started eating after gas passing, but felt abdominal distension. Diffuse paralytic ileus was diagnosed by abdominal X-ray, and she got started conservative therapy. During ST-36 electroacupuncture therapy, symptoms like abdominal pain and distension were improved and could stop opiod patch. But eating aggravated ileus again and clinical finding of mechanical bowel obstruction was appeared. Based on these cases, acupuncture and moxa therapy could be helpful for improving abdominal pain and ileus, but possibility of malignant bowel obstruction should be considered especially in cancer patients.