• The Journal of Korean Society for Radiation Therapy
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• v.19 no.2
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• pp.99-106
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• 2007

Purpose: The patient's position and anatomy during the treatment course little bit varies to some extend due to setup uncertainties and organ motions. These factors could affected to not only the dose coverage of the gross tumor but over dosage of normal tissue. Setup uncertainties and organ motions can be minimized by precise patient positioning and rigid immobilization device but some anatomical site such as prostate, the internal organ motion due to physiological processes are challenge. In planning procedure, the clinical target volume is a little bit enlarged to create a planning target volume that accounts for setup uncertainties and organ motion as well. These uncertainties lead to differences between the calculated dose by treatment planning system and the actually delivered dose. The purpose of this study was to evaluate the differences of interfractional displacement of organ and GTV based on the tomoimages. Materials and Methods: Over the course of 3 months, 3 patients, those who has applied rectal balloon, treated for prostatic cancer patient's tomoimage were studied. During the treatment sessions 26 tomoimages per patient, Total 76 tomoimages were collected. Tomoimage had been taken everyday after initial setup with lead marker attached on the patient's skin center to comparing with C-T simulation images. Tomoimage was taken after rectal balloon inflated with 60 cc of air for prostate gland immobilization for daily treatment just before treatment and it was used routinely in each case. The intrarectal balloon was inserted to a depth of 6 cm from the anal verge. MVCT image was taken with 5 mm slice thickness after the intrarectal balloon in place and inflated. For this study, lead balls are used to guide the registration between the MVCT and CT simulation images. There are three image fusion methods in the tomotherapy, bone technique, bone/tissue technique, and full image technique. We used all this 3 methods to analysis the setup errors. Initially, image fusions were based on the visual alignment of lead ball, CT anatomy and CT simulation contours and then the radiation therapist registered the MVCT images with the CT simulation images based on the bone based, rectal balloon based and GTV based respectively and registered image was compared with each others. The average and standard deviation of each X, Y, Z and rotation from the initial planning center was calculated for each patient. The image fusions were based on the visual alignment of lead ball, CT anatomy and CT simulation contours. Results: There was a significant difference in the mean variations of the rectal balloon among the methods. Statistical results based on the bone fusion shows that maximum x-direction shift was 8 mm and 4.2 mm to the y-direction. It was statistically significant (P=<0.0001) in balloon based fusion, maximum X and Y shift was 6 mm, 16mm respectively. One patient's result was more than 16 mm shift and that was derived from the rectal expansions due to the bowl gas and stool. GTV based fusion results ranging from 2.7 to 6.6 mm to the x-direction and 4.3$\sim$7.8 mm to the y-direction respectively. We have checked rotational error in this study but there are no significant differences among fusion methods and the result was 0.37$\pm$0.36 in bone based fusion and 0.34$\pm$0.38 in GTV based fusion.

• Journal of radiological science and technology
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• v.40 no.2
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• pp.187-195
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• 2017

Early diagnosis for upper facial trauma is difficult by using the standard Water's view (S-Water's) in general radiograph due to overlapping of anatomical structures, the uncertainty of patient positioning, and specific patients with obese, pediatric, old, or high-risk. The purpose of this study was to analyze appropriate exposure angles through a comparison of two different protocols (S-Water's vs. reverse Water's view (R-Water's)) by using a head phantom. A head phantom and general radiograph with 75 kVp, 400 mA, 45 ms 18 mAs, and SID 100 cm. Images of R-Water's were obtained by different angles in the range of $0^{\circ}$ to $50^{\circ}$, which adjusted an angle at 1 degree interval in supine position. Survey elements were developed and three observers were evaluated with four elements including the maxillary sinus, zygomatic arch, petrous ridge, and image distortion. Statistical significant analysis were used the Krippendorff's alpha and Fleiss' kappa. The intra-class correlation (ICC) coefficient for three observers were high with maxillary, 0.957 (0.903, 0.995); zygomatic arch, 0.939 (0.866, 0.987); petrous ridge, 0.972 (0.897, 1.000); and image distortion, 0.949 (0.830, 1.000). The high-quality image (HI) and perfect agreement (PA) for acquired exposure angles were high in range of the maxillary sinus ($36^{\circ}-44^{\circ}C$), zygomatic arch ($33^{\circ}-40^{\circ}$), petrous ridge ($32^{\circ}-50^{\circ}$), and image distortion ($44^{\circ}-50^{\circ}$). Consequently, an appropriate exposure angles for the R-Water's view in the supine position for patients with facial trauma are in the from $36^{\circ}$ to $40^{\circ}$ in this phantom study. The results of this study will be helpful for the rapid diagnosis of facial fractures by simple radiography.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.2
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• pp.181-187
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• 2004

Preparations of mesoporous materials using various templates and their applicability have been intensively investigated for many years. We studied on synthesizing mesoporous Ti02 with pores in which sensitive compounds having weak physico-chemical properties such as thermal or UV irradiation and low solubility in solvent are trapped. Prior to trapping OMC in the pores of mesoporous titania, OMC was nano-emulsified in O/W system using Lecithin. Thereafter the OMC was trapped in the pores of mesoporous titania using sol-gel method. Main focus of this work is to prepare OMC-trapped mesoporous titania and to trace the stability and solubility of nano-emulsified OMC in the pores of mesoporous titania, and compared with that of mesoporous silica. OMC-trapped mesoporous Inorganic-Organic hybrid titania showed higher factors in sun protecting and a skin penetration phenomenon was reduced.

• Polymer(Korea)
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• v.32 no.2
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• pp.163-168
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• 2008

Biomedical scaffold for tissue regeneration was fabricated by one of rapid prototyping processes, bioplotting system, with a biodegradable and biocompatible poly($\varepsilon$-carprolactone)(PCL). Through dynamic mechanical test, it was observed that the PCL scaffold manufactured by the bioplotting process has the superior mechanical properties compared to the conventional scaffold fabricated by a salt-leaching process, and the plotted scaffold could be employed as a potential scaffold to regenerating hard and soft tissue. The plotted scaffold was consisted of porous structures. which were interconnected with each pore to help cells be easily adhered and proliferated in the wall of pore tunnels, and metabolic nutrients can be transported within the matrix. By using the plotting system, we could adjust the pore size, porosity, strand pitch, and, strand diameter of PCL scaffolds, which were important parameters to control mechanical properties of the scaffolds, and consequently we could determine that the mechanically controlled scaffolds could be used as a matching scaffold for any required mechanical properties of the target organ. The fabricated 3D PCL scaffold showed enough possibility as a 3D biomedical scaffold, which was cell-cultured with chondrocytes.

• The korean journal of orthodontics
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• v.34 no.1 s.102
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• pp.63-70
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• 2004

The midpalatal suture area has some advantages for supporting miniscrews : it has no specific anatomical structure, it is composed of thick cortical bone, and covered with attached gingiva. So it is suitable area for inserting miniscrews. However, the midpalatal suture area appears thinner when seen in ceph. As a result, Clinicians can misunderstand that inserting miniscrews cause the problem, both the risk of perforation and the decrease of stability. The purpose of this article is measuring the vertical bone thickness of the midpalatal suture area for inserting miniscrews. The total of 25patient (male : 13, female : 12), who are in their twenties, were taken CT. The vertical bone thickness of the midpalatal suture area was measures from the transverse section of CT. As a result, We reached a conclusion from the differences of each area. It is as follows: 1. There is no significant difference between the thickness of male group and that of female group. 2. In coronal section, Bone thickness becomes thinner from the midpalatal suture to Left & Right side, in sagittal section, Bone thickness becomes thinner from incisive foramen to PNS. 3. The area that is within 3mm of left and right from the midpalatal suture area transversely and within 25mm backward from the incisive foramen sagittaly is enough for inserting miniscrews.

• Progress in Medical Physics
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• v.18 no.3
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• pp.126-133
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• 2007

A head-and-neck phantom was designed in order to evaluate remotely the quality of the delivery dose of intensity modulated radiation therapy (IMRT) in each institution. The phantom is homogeneous or inhomogeneous by interchanging the phantom material with the substructure like an air or bone plug. Monte Carlo simulations were executed for one beam and three beams to the phantom and compared with ion chamber and thermoluminescent dosimeter (TLD) measurements of which readings were from two independent institutions. For single beam, the ion chamber results and the MC simulations agreed to within about 2% TLDs agreed with the MC results to within 2% or 7% according to which institution read the TLDs. For three beams, the ion chamber results showed -5% maximum discrepancy and those of TLDs were $+2{\sim}+3%$. The accuracy of the TLD leadings should be increased for the remote dose monitoring. MC simulations are a valuable tool to acquire the reliability of the measurements in developing a new phantom.

• The Journal of the Korea Contents Association
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• v.20 no.8
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• pp.162-175
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• 2020

The purpose of this study is to deal with practical investigation, which blends symbolism on spatio-temporal level-especially typography in three-dimensional environment-and the symbolism of written language in the context of visual communication. Up until now, typography research and education have mainly been centered on two-dimensional environment and printing technology, such as the paper. However, this study is the result of this researcher's direct design and implementation of projects on typography aside from paper. Accordingly, this study is to provide an opportunity to raise the level of reason and expression used in visual communication to a new level and to expand its scope. To ensure the efficient progress of the project, this study was to identify the structure, system, and process of communication first. Furthermore, this study was to investigate two-dimensional and three-dimensional typography as the backbone of visual communication. In addition, several representative 3D typography works are analyzed in context and used as the conceptual framework of the project conducted for this study. Based on these results, this research verifies and suggests the possibility practically and objectively by creating the project series entitled Rhetorical Space in 3D typography. In addition, this research gives an opportunity to visualize ideas aimed at the development of character-based visual language and visual communication design in the realm of the more spatial, physical, and three-dimensional public environment.

• Journal of the Korean Geophysical Society
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• v.6 no.3
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• pp.139-153
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• 2003

Subsurface information is one of the most important factors in the archaeological excavation. To obtain the information on the underground, geophysical prospecting is becoming a popular method. This study is on the small rocky islands located 200m away from the shoreline of Gampo, Gyeongju city, Korea. According to the historical records and field surveys, it was revealed as the tomb of King Munmu of Shilla Dynasty. However, the questions and debates, such as whether it is really the tomb of King Moonmu or not, and whether it is a buried place or not, are still remains, in addition to the incompletion of precise surveying and scientific studies. The scope of this study contains the researches on the above problems and debates using the geophysical and geological methods and techniques. The rocky islands around the submerged Tomb of King Moonmu is composed of granite, and sag exists inside of the islands. Sea water enters through the east groove by wave and is drained to the west slot by hydraulic gradient, since west slot is 15cm lower than the east. Sag inside of the islands is believed to be extended and widened from pre-existed sinkage by applying tools like chisel in the joints and cracks. It is concluded that the submerged megalith inside of sag was from the rock block which was developed by joints. Geophysical surveys reveal that there is no artificial structure or stone/china/steel chest, under the m egalith and rocky island. Researches show that the tomb of King Moonmu was constructed in the small rocky island artificially. However, the evidences show that planners and constructors of the tomb made every possible effort to preserve the natural environment and condition. It is strongly believed that the megalith was sort of alter to sprinkle bone-ash rather than buried place.

• Polymer(Korea)
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• v.36 no.3
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• pp.357-363
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• 2012

Surface-modified poly(L-lactic acid) (PLLA) films and scaffolds were treated with plasma discharge in oxygen gas and subsequently subjected to $in$ $situ$ grafting of acrylic acid (AA) in order to increase the cell compatibility. The surface of AA-grafted PLLA was converted to hydroxyapatite (HA)-deposited PLLA in stimulated body fluid (SBF). After the samples were immersed in phosphate-buffered saline (PBS), fetal bovine serum (FBS), normal saline, or cell medium, the water contact angles were significantly reduced on the surface of HA-deposited PLLA. Chondrocyte and osteoblast showed a higher attachment and cell proliferation on HA-deposited surfaces and in particular, it was confirmed that chondrocyte was considerably influenced by HA. However, osteoblast showed better cell proliferation on the surfaces immersed in FBS, cell medium or HA-deposited surface. In addition, the cell proliferation in 3D scaffolds was much higher than that on film type, irrespective of chondrocyte and osteoblast. Therefore, such surface-modified PLLAs are expected to be useful as organic-inorganic hybrid scaffolds in the regeneration of cartilage and bone.

• The Journal of the Convergence on Culture Technology
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• v.6 no.3
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• pp.457-462
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• 2020

Osteoporosis is a disease that occurs mainly in the elderly and increases the risk of fractures due to structural deterioration of bone mass and tissues. The purpose of this study are to assess the relationship between nutritional components and osteoporosis and to evaluate models for predicting osteoporosis based on nutrient components. In experimental method, association was performed using binary logistic regression, and predictive models were generated using the naive Bayes algorithm and variable subset selection methods. The analysis results for single variables indicated that food intake and vitamin B2 showed the highest value of the area under the receiver operating characteristic curve (AUC) for predicting osteoporosis in men. In women, monounsaturated fatty acids showed the highest AUC value. In prediction model of female osteoporosis, the models generated by the correlation based feature subset and wrapper based variable subset methods showed an AUC value of 0.662. In men, the model by the full variable obtained an AUC of 0.626, and in other male models, the predictive performance was very low in sensitivity and 1-specificity. The results of these studies are expected to be used as the basic information for the treatment and prevention of osteoporosis.