• Progress in Medical Physics
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• v.19 no.1
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• pp.80-88
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• 2008

Recent radiotherapy dose planning system (RTPS) generally adapted the kernel beam using the convolution method for computation of tissue dose. To get a depth and profile dose in a given depth concerened a given photon beam, the energy spectrum was reconstructed from the attenuation dose of transmission of filter through iterative numerical analysis. The experiments were performed with 15 MV X rays (Oncor, Siemens) and ionization chamber (0.125 cc, PTW) for measurements of filter transmitted dose. The energy spectrum of 15MV X-rays was determined from attenuated dose of lead filter transmission from 0.51 cm to 8.04 cm with energy interval 0.25 MeV. In the results, the peak flux revealed at 3.75 MeV and mean energy of 15 MV X rays was 4.639 MeV in this experiments. The results of transmitted dose of lead filter showed within 0.6% in average but maximum 2.5% discrepancy in a 5 cm thickness of lead filter. Since the tissue dose is highly depend on the its energy, the lateral dose are delivered from the lateral spread of energy fluence through flattening filter shape as tangent 0.075 and 0.125 which showed 4.211 MeV and 3.906 MeV. In this experiments, analyzed the energy spectrum has applied to obtain the percent depth dose of RTPS (XiO, Version 4.3.1, CMS). The generated percent depth dose from $6{\times}6cm^2$ of field to $30{\times}30cm^2$ showed very close to that of experimental measurement within 1 % discrepancy in average. The computed dose profile were within 1% discrepancy to measurement in field size $10{\times}10cm$, however, the large field sizes were obtained within 2% uncertainty. The resulting algorithm produced x-ray spectrum that match both quality and quantity with small discrepancy in this experiments.

• The korean journal of orthodontics
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• v.28 no.2 s.67
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• pp.219-229
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• 1998

The purpose of this study is to define the characteristics of the skeleton and soft tissues of severe adult class III malocclusion. The materials selected for this study were lateral cephalograms of 112 adult class III malocclusion patients with ANB difference below -2 degrees. and the mean age was 22.9 years old. The normal control sampler consisted of lateral cephalograms of 50 adults in normal occlusion and the mean age was 22.1 years old. The Horizontal reference line was FH line and the vertical reference line was nasion perpendicular to FH line. The skeletal and soft tissue characteristics of Class III malocclusion are as follows : 1. In the skeletal profile evaluated by vertical reference line (Nasion perpendicular to FH), the forehead and maxilla was similar to normal, but the mandible was protruded significantly. 2. The soft tissue profile is concave. The thickness of soft tissue covering forehead area and nose is within normal range. but the upper lip is thicker and the nasolabial angle is smaller than normal. The lower lip and inferior labial sulcus is thinner than normal. The degree of eversion of lower lip is lesser than normal. 3. The cranial base of class III malocclusion is shorter and saddle angle is smaller than normal. 4. The location of midface evaluated in relations to cranial base is within normal range but, the length of midface is shorter than normal when compared from the deep portion of the facial skeleton. 5. The location of maxilla in reference to cranial base is within normal range but the length of maxilla was shorter in class III malocclusion. 6. The mandible was protruded, ramus height and body length, gonial angle were greater than normal, and the chin angle was smaller. 7. Upper incisor was proclined, lower incisor was retroclined.

• Journal of Korean Society of Forest Science
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• v.58 no.1
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• pp.41-47
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• 1982

The large devastated land in Young-il district, Gyeongsangbusdo, had been existed for a long time, and the Korean government had invested 3.8 billion won to control soil erosion of the area for 5 years from 1973 to 1977. This research was to investigate the changes of the soil profile and vegetation structure in the 3rd, 6th and 9th years since soil erosion control had implemented. The results obtained in this study are as follows: 1) The thickness of the litter layer (L), the fermentation layer(F), the humified layer(H) and the surface soil layer(S) increased with increasing years after implements soil erosion control project had started. 2) The H layer was not showed for the three years since the project had implemented but was in the sixty year. 3) The soil chemical elements including the organic matter and total nitrogen increased with increasing years after the project had started, the amounts of organic matter and total nitrogen were three and seven times higher respectively in the nineth year after project had started. The amounts of organic matter and total nitrogen were three and seven times higher, respectively in the nineth year after project started than those before. 4) Among the grasses and trees which had been sowed or planted during project period, the summed domination ratios for arundinella hirta var ciliare. Themeda japonica, Cymbopogen goeringi and Lespedeza bicolor decreased rapidly, while those for Robinia pesudoacacia and Pinus densiflora increased with increasing years after the project started. 5) The appearance of Quercus seedlings suited to this area and Pinus densiflora seedling which is a subclimax species increased with increasing years after the project started.

• Journal of Animal Science and Technology
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• v.47 no.5
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• pp.721-730
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• 2005

Effects of levels of Bomboo Vinegar Liquids(BVL) on growth performance, serum profile and meat quality in employing 90 pigs were investigated. Ninety pigs were allocated into 3 groups and fed by dietary levels of BVL 0(control), 2.0 and 4.0% were included in experimental diets of each of the groups. Concentrated diet was supplemented with 2.0 and 4.0% BVL. The results showed that the daily weight gains and the feed conversion increased significantly(p<0.05) in 2.0% BVL and the feed intake increased slightly. The glucose and the cholesterol contents at the serum decreased significantly(p<0.05) in 2.0 and 4.0% BVL. On the other hand the total protein concentration and the blood urea nitrogen(BUN) increased significantly(p<0.05) in 4.0% BVL. The carcass weight increased significantly(p<0.05) in 4.0% BVL, and back fat thickness had decreased significantly(p<0.05) in 2.0 and 4.0% BVL. The carcass grade tended to increase in 2.0 and 4.0% BVL. The total fat content of loin tended to increase in 2.0 and 4.0% BVL while the cholesterol content decreased significantly(p<0.05). The pH had lower slightly in 2.0 and 4.0% BVL, the lightness and the yellowness of the meat color had higher significantly(p<0.05) while the redness decreased. Shear force values had lower significantly(p<0.05) in 2.0 and 4.0% BVL. For the fatty acid composition, the saturated fatty acids decreased significantly(p<0.05) in 2.0 and 4.0% BVL while unsaturated fatty acids(oleic acid and linoleic acid) increased significantly(p<0.05). For the sensory evaluation, 2.0 and 4.0% BVL had a significant(p<0.05) effect of diminishing the odor and improving the appearance. The taste was also significantly(p<0.05) improved. In conclusion the 2.0% BVL had a positive effect on the feeding performance, the carcass grade and the meat quality characteristics therefore 2.0% BVL is the appropriate supplemental levels of BVL for finishing pigs.

• Radiation Oncology Journal
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• v.16 no.3
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• pp.337-345
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• 1998

Purpose : To obtain the uniform dose at limited depth to entire surface of the body, the dose characteristics of degraded electron beam of the large target-skin distance and the dose distribution of the six-dual electron fields were investigated Materials and Method : The experimental dose distributions included the depth dose curve, spatial dose and attenuated electron beam were determined with 300 cm of target-skin distance (TSD) and full collimator size (35*35 $cm^2$ on TSD 100 cm) in 4 MeV electron beam energy. Actual collimated field size of 105 cm * 105 cm at the distance of 300 cm could include entire hemibody. A patient was standing on step board with hands up and holding the pole to stabilize his/her positions for the six-dual fields technique. As a scatter-degrader, 0.5 cm of acrylic plate was inserted at 20 cm from the body surface on the electron beam path to induce ray scattering and to increase the skin dose. Results : The full width at half maximum(FWHM) of dose profile was 130 cm in large field of 105*105 $cm^2$ The width of $100\pm10\%$ of the resultant dose from two adjacent fields which were separated at 25 cm from field edge for obtaining the dose unifomity was extended to 186 cm. The depth of maximum dose lies at 5 mm and the 80$\%$ depth dose lies between 7 and 8 mm for the degraded electron beam by using the 0.5 cm thickness of acrylic absorber. Total skin electron beam irradiation (TSEBI) was carried out using the six dual fields has been developed at Stanford University. The dose distribution in TSEBI showed relatively uniform around the flat region of skin except the protruding and deeply curvatured portion of the body, which showed excess of dose at the former and less dose at the latter. Conclusion : The percent depth dose, profile curves and superimposed dose distribution were investigated using the degraded electron beam through the beam absorber. The dose distribution obtained by experiments of TSEBI showed within$\pm10\%$ difference except the protruding area of skin which needs a shield and deeply curvatured region of skin which needs boosting dose.

• The korean journal of orthodontics
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• v.27 no.1
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• pp.65-78
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• 1997

This study was carried out in order to determine soft tissue response to incisor movement and mandibular repositioning and to determine feasibility of predicting vertical and horizontal changes in soft tissue with hard tissue movement. For this study, cephalometric records of 41 orthodontically treated adult females who had Angle's Class II division 1 malocclusion were selected and stepwise multiple regression analysis was employed. Following conclusions were obtained by analysing the changes of soft tissue and hard tissue before and after treatment. 1. Hard tissue measurements that showed significant changes before and after treatment were horizontal and angular changes of maxillary incisor, horizontal,vertical and angular changes of mandibular incisor, overjet, overbite, interincisal angle, mandibular repositioning, A,B, skeletal convexity and soft tissue measurements that showed significant changes were horizontal, thickness and angular changes of upper lip, horizontal and angular changes of lower lip, interlabial angle, nasolabial angle labiomental angle, Sri, Ss, Si and soft tissue convexity(P<0.05). 2. All Soft tissue measurements changed significantly before and after treatment had between one and four hard tissue independent variables at statistically significant level, indicating that all soft tissue changes were direct relationship with hard tissue changes 3. Ova jet, horizontal change of maxillary incisor, horizontal change of maxillary root apex and horizontal change of pogonion entered into prediction equations most frequentely indicating that they were more significant variables in prediction of vertical and horizontal changes in the soft tissue with treatment, but vertical changes of mandibular incisor not entered any prediction equations, indicating that it was not considered a good predictor for soft tissue changes with maxillary incisor retraction. 4. Horizontal and vertical changes in subnasale were found to have most independent variables, significant at the 0.05 level in prediction-equations(${\Delta}$Sn(H):Ur, Is(H), Pg(H), UIA,${\Delta}$Sn(V): Is(H), Pg(H), overjet, A), indicating that subnasale changes are influenced by complex hard tissue interaction. 5. Multiple correlation coefficient($R^2$) of the soft tissue prediction equations ranges from 0.2-0.6.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.916-921
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• 2011

This study was carry out on a Jang-Won series (fine loamy, mixed, mesic family of typic fragipan) that were established and classified as a fragipan soil in Korea. The morphological, physical, chemical and minerals characteristics of Jang-Won series were studied to determine the genesis of fragipan soils in natural environment. Each sample was analyzed for its physical, chemical and mineralogical characteristics. The particle size distribution of samples was measured using pipette method. Clay minerals were investigated on parallel-oriented specimens of the clay fraction ($<2{\mu}m$) from each horizon, separated by sieving and centrifugation, using X-ray diffraction (XRD) analysis. Micromorphological observations were made on thin sections prepared from soil blocks impregnated with Crystic Resin, cut and ground to less than $30{\mu}m$ in thickness, and finally polished with diamond paste. Most horizons have pH values in the range of fewer than 5.0 and have very low base-saturation values. Their textural classification ranges from silt loam to loam, the lower horizons being the finer. The clay fraction revealed the occurrence of illite, kaolinite, chlorite and vermiculite. The micro-morphological analysis carries out thin sections from each soil profile. The silt concentrations occur as extremely dense and homogenous bands or zones of silt-sized materials, brownish in colour in plane-polarized light and anisotropic in cross-polarized light, surrounding or adhering to skeleton grains. The genesis of fragipan in the Jangweon series assumed composition of clay fraction rather than silt concentration. Therefore, this results suggested an authentic interpretation which Jangweon series is classification as Typic Fragiochrepts.

• The korean journal of orthodontics
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• v.30 no.2 s.79
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• pp.261-272
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• 2000

Severe skeletal anteroposterior and vertical discrepancy is difficult to obtain satisfactory result by only orthodontic treatment, and much anteroposterior movement and treatment stability require orthodontic treatment with orthognathic surgery. The treatment goal of mandibular prognathic patients is to promote the function of stomatognathic system including mastication and phonetics, to improve the esthetics of facial profile and to maintain stability. Positional changes of hyoid bone, pharynx and tongue were seen with mandibular movement after orthognathic surgery. This study was performed to observe the changes of perimandibular tissues of orthodontic patients with skeletal mandibular prognathism who treated with orthodontic treatment, and the changes of hyoid bone, pharyx and tongue by relapse or recurrance after before and after orthognathic surgery and retention. The 22 patients who had mandibular prognathism were selected. They treated with orthodontic treatment with sagittal split ramus osteotomy as orthognathic surgery. And lateral cephalometric radiographs were taken 3 times : pre-surgery (T1), immediate post-surgery (T2) and 2 years alter retention (T3). The results were as follows : 1. The hyoid bone returned back after clockwise rotation to maxilla and occlusal plane during retention (P<0.01). 2. The hyoid bone moved posterior-inferiorly by mandibular surgery and returned back anterior-superior after retention. (P<0.01) 3. The changes of pharyngeal depth showed a little decrease at upper area in post- surgery, but it was not a significant difference generally through before, after and retention. 4. In relating to tongue base, the angle of tongue base was decreased and the dorsal area of tongue base moved to inferior-posterior direction and to superior direction again after retention (P<0.01). 5. Related to the thickness of upper and lower lip, the thickness of upper lip decreased after surgery, and the soft tissues below lower lip increased after surgery and decreased after retention.

• Economic and Environmental Geology
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• v.49 no.6
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• pp.469-477
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• 2016

To evaluate the $CO_2$ storage capacity for the reservoir rock, the laboratory scale technique to measure the amount of $scCO_2$, replacing pore water of the reservior rock after the $CO_2$ injection was developed in this study. Laboratory experiments were performed to measure the $scCO_2$ displacement efficiency of the conglomerate and the sandstone in Janggi basin, which are classified as available $CO_2$ storage rocks in Korea. The high pressurized stainless steel cell containing two different walls was designed and undisturbed rock cores acquired from the deep drilling site around Janggi basin were used for the experiments. From the lab experiments, the average $scCO_2$ displacement efficiency of the conglomerate and the sandstone in Janggi basin was measured at 31.2% and 14.4%, respectively, which can be used to evaluate the feasibility of the Janggi basin as a $scCO_2$ storage site in Korea. Assuming that the effective radius of the $CO_2$ storage formations is 250 m and the average thickness of the conglomerate and the sandstone formation under 800 m in depth is 50 m each (from data of the drilling profile and the geophysical survey), the $scCO_2$ storage capacity of the reservoir rocks around the probable $scCO_2$ injection site in Janggi basin was calculated at 264,592 metric ton, demonstrating that the conglomerate and the sandstone formations in Janggi basin have a great potential for use as a pilot scale test site for the $CO_2$ storage in Korea.

• Radiation Oncology Journal
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• v.9 no.1
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• pp.131-141
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• 1991

A comprehensive set of dosimetric measurements has been made on the Varian Clinac 1800 15 MV photon beam. Beam quality, percentage depth dose, dose in the build up region, output, symmetry and flatness, transmission through iead (Cerrobend), tray attenuation, isodose curves for the open and wedged fields were measured using 3 dimensional water phantom dosimetry system (including film densitometer system) and polystyrene phantoms. These dosimetric measurements sufficiently characterized the beam to permit clinical use. The depth dose characteristics of photon beam is $d_{max}$ of 3.0 cm and percentage depth dose of $76.8\%$ at 10 cm,100 cm source-surface distance, field size of $10\times10\;cm^2$ for 15 MV X-ray beam. The Output factors ranged 0.927 for $4\times4\;cm^2$ field to 1,087 for $35\times35\;cm^2$ field. The build-up level of maximum dose was at 3.0 cm and surface dose was approximately $15.5\%$ for a field size $10\times10\;cm^2$ The stability of output is $within\pm1\%$ and flatness and symmetry are $within\pm3\%$. The half value thickness (HVL) of lead is 13 mm, which corresponds to an attenuation coefficient of $0.053\;mm^{-1}$. These figures compare facorably with the manufacturesr`s specifications.