• Progress in Medical Physics
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• v.9 no.3
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• pp.155-162
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• 1998

Ho-l66 was produced by neutron reaction in a reactor at the Korea Atomic Energy Institute (Taejon, Korea). Ho-l66 emits a high energy beta particles with a maximum energy of 1.85 MeV and small proportion of gamma rays (80 keV). Therefore, the radiation absorbed dose estimation could be based on the in-vivo quantification of the activity in tumors from the gamma camera images. Approximately 1 mCi of Ho-l66 in solution was mixed into the flood phantom and planar scintigraphic images were acquired with and without patient interposed between the phantom and scintillation camera. Transmission factor over an area of interest was calculated from the ratio of counts in selected regions of the two images described above. A dual-head gamma camera(Multispect2, Siemens, Hoffman Estates, IL, USA) equipped with medium energy collimators was utilized for imaging(80 keV${\pm}$10%). Fifty-nine year old female patient with hepatoma was enrolled into the therapeutic protocol after the informed consent obtained. Thirty millicuries(110MBq) of Ho-166-CHICO was injected into the right hepatic arterial branch supplying hepatoma. When the injection was completed, anterior and posterior scintigraphic views of the chest and pelvic regions were obtained for 3 successive days. Regions of interest (ROIs) were drawn over the organs in both the anterior and posterior views. The activity in those ROIs was estimated from geometric mean, calibration factor and transmission factors. Absorbed dose was calculated using the Marinelli formula and Medical Internal Radiation Dose (MIRD) schema. Tumor dose of the patient treated with 1110 MBq(30 mCi) Ho-l66 was calculated to be 179.7 Gy. Dose distribution to normal liver, spleen, lung and bone was 9.1, 10.3, 3.9, 5.0 % of the tumor dose respectively. In conclusion, tumor dose and absorbed dose to surrounding structures were calculated by daily external imaging after the Ho-l66 therapy for hepatoma. In order to limit the thresholding dose to each surrounding organ, absorbed dose calculation provides useful information.

• Progress in Medical Physics
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• v.27 no.2
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• pp.86-92
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• 2016

An absorbed dose calculation method using a digital phantom is implemented in normal organs. This method cannot be employed for calculating the absorbed dose of tumor. In this study, we measure the S-value for calculating the absorbed dose of each organ and tumor. We inject a radioisotope into a torso phantom and perform Monte Carlo simulation based on the CT data. The torso phantom has lung, liver, spinal, cylinder, and tumor simulated using a spherical phantom. The radioactivity of the actual absorbed dose is measured using the injected dose of the radioisotope, which is Cu-64 73.85 MBq, and detected using a glass dosimeter in the torso phantom. To perform the Monte Carlo simulation, the information on each organ and tumor acquired using the PET/CT and CT data provides anatomical information. The anatomical information is offered above mean value and manually segmented for each organ and tumor. The residence time of the radioisotope in each organ and tumor is calculated using the time activity curve of Cu-64 radioactivity. The S-values of each organ and tumor are calculated based on the Monte Carlo simulation data using the spatial coordinate, voxel size, and density information. The absorbed dose is evaluated using that obtained through the Monte Carlo simulation and the S-value and the residence time in each organ and tumor. The absorbed dose in liver, tumor1, and tumor2 is 4.52E-02, 4.61E-02, and 5.98E-02 mGy/MBq, respectively. The difference in the absorbed dose measured using the glass dosimeter and that obtained through the Monte Carlo simulation data is within 12.3%. The result of this study is that the absorbed dose obtained using an image can evaluate each difference region and size of a region of interest.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.126-126
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• 2017

본 연구는 가축분뇨를 퇴비화 하는 과정에서 흔히 사용되는 수분조절제인 톱밥, 왕겨 등의 가격적 부담으로 인해 좀 더 가격이 저렴한 수분조절제들의 성분을 비교 분석하여 어떤 차이가 있는지 확인하기 위하여 실시되었다. 이를 위해 6가지 수분조절제를 토대로 유도결합플라즈마분광계 장비를 이용하여 화학적 분석, 인장시험기를 이용하여 물리적 분석을 하였다. 화학적 분석을 통해 수분조절제 내 함유되어 있는 성분들을 분석하였으며 물리적 분석을 통해 중량, 함수율, 흡수율, 인장강도 등을 측정하였다. 화학적으로 분석을 했을 시 K, Cd, Pb, Ni, Zn, Cu, Cr, As 등을 측정을 하였으며 앞서 분석했던 각각의 성분들은 농촌진흥청에 명시되어 있는 유해성분의 최대량보다 대부분 적게 측정이 되었다. 물리적으로 분석을 했을 시, 각 수분조절제의 함수율은 최소 10.29%에서 최대 16.07%까지 측정이 되었다. 전단강도는 기존 상태가 가장 높게 측정이 되었으며 다음으로 건조상태 흡수상태로 측정이 되었다. 일반적으로 사용하기에는 흡수율이 가장 높은 우드 브리켓-1이 가장 적합한 것으로 판단된다.

• The Korean Journal of Ecology
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• v.16 no.4
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• pp.417-428
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• 1993

Branching growth pattern of Mugnolza denuduta is likely to be originated from two growth strategies: environment overcoming strategy and life maintenance strategy, which coexist in a tree. Growth rate of branches was strongly correlated with relative light intensity (P<0.001) and physical contact (P<0.01), however there is no significant correlation between growth rate and direction of branch. When relative light intensity is less than 1%, the growth was restricted by physical contact with the surrounding branches. In contrast, the growth was rarely restricted by physical contact when relative light intensitiy was 10% or more. The branching rate was significantly affected by the presence or absence of physical contact (P<0.05), but it was not significantly affected by relative light intensity nor by the direction of branch. In the beginning stage of the growth, the ratio of the material allocation from main branch to subbranch was large and varied with the influence of surrounding environment. These various growth rates, which implicate a variety of material allocation ratios (0.16~0.98), affect branch growth pattern through the optimum growth strategies. The growth and arrangement of branches of Magnolia denudata display the solar collectors to maximize the total amount of energy absorbed and to overcome the restriction of the environment.

• Journal of the Korean Wood Science and Technology
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• v.45 no.3
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• pp.360-367
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• 2017

This study was carried out to compare the characteristics of low density fiberboards (LDFs) manufactured with different adhesive types such as melamine urea formaldehyde (MUF), phenol formalehyde (PF), emulsified MDI (eMDI) and latexes resins. As results, hard LDFs were successfully manufactured by MUF, PF and eMDI resins. Thermal conductivities of all LDFs were significantly lower than commercial medium density fiberboard. Especially, all LDFs showed comparable thermal insulation performance with extruded polystyrene foam (XPS). LDF manufactured with eMDI resins showed the highest physical properties such as thickness/length swelling by water absorption and bending strength.

• Journal of Korea Foresty Energy
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• v.25 no.2
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• pp.28-33
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• 2006

This study was conducted to find potentialities of the leaves of gingko tree (Gingko biloba L.) which has been planted as a roadside tree in Korea because of its resistance on air pollution, insect, fungi, etc. Various amounts of the leaves were mixed with wasted wood particles to manufacture particleboard. Their influences on physical and mechanical properties and the formaldehyde emission of PB were investigated. Physical and mechanical properties, such as density, modulus of rupture (MOR), and internal bond (IB) strength, of manufactured particleboard were not much different from those of control board. Formaldehyde emission values were decreased with increasing amount of leaves in PB prepared. Especially, particleboard made with 3 percent of leaves was decreased to $1.66mg/{\ell}$ in formaldehyde emission, which is about 40% lower emission than that of control. From these results, the leaves of gingko tree may be considered as a formaldehyde emission lowering additive in a functional PB manufacturing process.

• The Journal of Korean Physical Therapy
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• v.16 no.2
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• pp.1-16
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• 2004

The purpose of this paper is to review changes in articular cartilage properties from the joint immobilization. Joint immobilization is accompanied not only by many disorders including rheumatologic disorders, degenerative disorders, trauma and fracture but treatment for disorders. Articular cartilage are sensitive to mechanical events. Immobilization is associated with cartilage degradation that may cause joint pain and reduced range of motion. An understanding of the effects of immobilization on the articular cartilage will help to plan of physical therapy program

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5384-5393
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• 2015

We investigated the effects of milling degrees of rice on characteristics of the steamed rice and fermentation of rice koji as a raw material of cheongju. It was studied for 8 months about ratio of water absorption and koji charateristics according to milling degrees. The The more increasing rice milling, the less the protein contents of milled rice was continuously decreased and the lipid and ash contents were sharply decreased to until the milling degrees 20%, and then gradually decreased. When steeping the milled rice, higher milling degrees raised rapid water asorption and higher maximum water asorption, lower water temperature raised gradual water absorption and higher maximum absorption. The longer steeping time, the steamed rice milling degrees 40% showed significantly lower hardness and springness than others. Alcohol contents of the fermented mash with rice koji milling degrees 10% was lower with 16.3-16.9%(v/v) than other sample's 17.1-17.5% (v/v). The total acid contents showed that the milling degrees 10% indicated the lowest content(0.71-0.76%) and the milling degrees 30% indicated highest content(0.93-0.99%). Within the same milling degrees, As the steeping time increases, the total acid contents imcrease. In conclusion, the milling degrees influenced on physicochemical chatacteristics of rice and steamed rice condition.

• Journal of the Korean Chemical Society
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• v.37 no.2
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• pp.206-212
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• 1993

Syntheses and properties of zwitterionic dithiocarbamates and their nickel(Ⅱ) complexes are described. The complexes have been characterized by mass infrared and electronic absorption spectroscopy, and conductivity measurement. Ni(Ⅱ)-dithiocarbamato complexes are soluble in polar solvents such as water, methanol, and acetone etc. The possible structures were proposed on the basis of elemental analyses and physical properties.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2009.11a
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• pp.258-260
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• 2009

광촉매능을 갖는 $TiO_2$는 국내외적으로 많은 연구가 진행되고 있으며, 빛의 조사로 발생하는 다양한 물리 화학적 촉매특성이 환경정화뿐만 아니라 및 에너지 흡수차단 기능도 갖고 있어 최근 주목을 받고 있다. 본 연구에서는 친수성을 가지는 친환경 창호소재용 및 초친수성을 가지는 자동차의 사이드미러 개발을 위해 유리표면에 이종밴드갭을 갖는 복합구조 $TiO_2/Cr_2O_3/Cr$ 박막을 스퍼터링법으로 증착하여 중간층인 $Cr_2O_3$의 역할을 고찰하였다. Cr, 결정질 $Cr_2O_3$ 기판의 경우 Anatase상과 Rutile상이 공존하는 미세조직이 관찰 되었으며 비정질 $Cr_2O_3$ 기판의 경우는 균일한 결정질 anatase-$TiO_2$상이 나타났다.