• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.12
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• pp.169-174
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• 2016

In this study, we evaluated the virtual reality model for dental implant surgery and discussed about the method to make the surgical environment for virtual reality with practical patient data. The anatomical model for patient face was fabricated by facial and oral scan data based on CT data. The simulation scenario was composed step by step fashion with Unity3D. From incision and sinus bone graft procedure which is needed to this patient model to implant installation and bone graft was included in this scenario. We used the HMD and leap motion for immersiveness and feeling of real operation. Twenty training doctor was attended this simulation study, and surveyed their satisfactory results by questionnaire. Implant surgery education program was showed the possibilities of educational tool for dental students and training doctors. Virtual reality for surgical education with HMD and leap motion had advantages, in terms of cheap prcie, easy access.

• International Commerce and Information Review
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• v.16 no.4
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• pp.409-437
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• 2014

The purpose of this study is to present the specific ways of successful localization by analyzing the success and failures case for localization within the framework of the strategic models through a theoretical background and strategic models of localization. The strategic models of localization are divided by management aspects such as the localization of product and sourcing, the localization of human resources, the localization of marketing, the localization of R&D, harmony with a local community and delegation of authority between headquarters and local subsidiaries. The results, by comparing and analyzing the success and failures case for localization of individual companies operating in India, indicate that in terms of localization of product and sourcing, there are successful companies which procure a components locally and produce a suitable model which local consumers prefer and the failed companies which can not meet local consumers' needs. In case of localization of human resources, most companies recognize the importance of this portion and make use of superior human resource aggressively through a related education. In case of localization of marketing, It is found that the successful companies perform pre-market research & management and build a effective marketing skills & after service network and select local business partner which has a technical skills and carry out a business activities, customer support, complaint handling with their own organization. In terms of localization of R&D, the successful major companies establish and operate R&D center to promote a suitable model for local customers. In part of harmony with a local community, it shows that companies which made a successful localization understand the cultural environment and contribute to the community through CSR. In aspect of delegation of authority between headquarters and local subsidiaries, it is found that most of Korean companies are very weak for this part. there is a tendency to be determined by the head office rather than local subsidiaries. Implication of this thesis is that Korean enterprises in India should carry forward localization of products and components, foster of local human resource who recognize management and system of company and take part in voluntary market strategy decision, wholly owned subsidiary, establishment and operation of R & D center, understanding of local culture and system, corporate social responsibility, autonomy in management.

• Investigative Magnetic Resonance Imaging
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• v.21 no.2
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• pp.65-70
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• 2017

Purpose: To optimize the saturation time and maximizing the pH-weighted difference between the normal and ischemic brain regions, on 3-tesla amide proton transfer (APT) imaging using an in vivo rat model. Materials and Methods: Three male Wistar rats underwent middle cerebral artery occlusion, and were examined in a 3-tesla magnetic resonance imaging (MRI) scanner. APT imaging acquisition was performed with 3-dimensional turbo spin-echo imaging, using a 32-channel head coil and 2-channel parallel radiofrequency transmission. An off-resonance radiofrequency pulse was applied with a Sinc-Gauss pulse at a $B_{1,rms}$ amplitude of $1.2{\mu}T$ using a 2-channel parallel transmission. Saturation times of 3, 4, or 5 s were tested. The APT effect was quantified using the magnetization-transfer-ratio asymmetry at 3.5 ppm with respect to the water resonance (APT-weighted signal), and compared with the normal and ischemic regions. The result was then applied to an acute stroke patient to evaluate feasibility. Results: Visual detection of ischemic regions was achieved with the 3-, 4-, and 5-s protocols. Among the different saturation times at $1.2{\mu}T$ power, 4 s showed the maximum difference between the ischemic and normal regions (-0.95%, P = 0.029). The APTw signal difference for 3 and 5 s was -0.9% and -0.7%, respectively. The 4-s saturation time protocol also successfully depicted the pH-weighted differences in an acute stroke patient. Conclusion: For 3-tesla turbo spin-echo APT imaging, the maximal pH-weighted difference achieved when using the $1.2{\mu}T$ power, was with the 4 s saturation time. This protocol will be helpful to depict pH-weighted difference in stroke patients in clinical settings.

• Radiation Oncology Journal
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• v.12 no.1
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• pp.27-31
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• 1994

There are a number of reports suggesting that there may be a correlation between the clinical response to radiotherapy in various tumors and the clonogenic survival of cell lines derived from these tumors following exposure to 2 Gy(SF2). Authors conducted this study to determine SF2 for cells in primary culture from surgical specimens. The tumor tissues with squamous cell carcinoma of uterine cervix and head and neck were obtained. The tumor tissues were disaggregated to single cells by incubating with collagenase type w for 2 hours with constant stirring. Single cell suspensions were inoculated in four 24-well plates precoated with cell adhesive matrix. After 24 hours of incubation at 37$ ^{\circ}C $, rows of four wells were then irradiated, consisting of control set and five other sets each receiving doses of 1,2,3,4, and 6 Gy. After incubation for a total of 13 days, the cultures were stained with crystal violet and survival at each dose was determined by quantitative image analysis system, To determine whether cell growth was of epithelial origin, immunocytochemical staining with a mixture of cytokeratin and epithelial monoclonal antibodies were performed on cell cultures. During the period of this study, we received 5 squamous cell carcinoma specimens of head and neck and 20 of uterine cervical carcinoma. Of these, 15 yielded enough cells for radiosensitivity testing. This resulted an overall success rate of 60$ \% $. The mean SF2 value for 15 tumours was 0.55$\pm$0.17 ranging from 0.20 to 0.79. These results indicate that there is a broad range of sensitivities to radiation in same histologic type. So with a large patient population, we plan to determine whether a different SF2 value is associated with tumours that are controlled with radiotherapy than those that are not.

• Radiation Oncology Journal
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• v.25 no.4
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• pp.242-248
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• 2007

Purpose: To study the effect of recombinant human epidermal growth factor (rhEGF) on oral mucositis induced by cisplatin and radiotherapy in a mouse model. Materials and Methods: Twenty-four ICR mice were divided into three groups-the normal control group, the no rhEGF group (treatment with cisplatin and radiation) and the rhEGF group (treatment with cisplatin, radiation and rhEGF). A model of mucositis induced by cisplatin and radiotherapy was established by injecting mice with cisplatin (10 mg/kg) on day 1 and with radiation exposure (5 Gy/day) to the head and neck on days $1{\sim}5$. rhEGF was administered subcutaneously on days -1 to 0 (1 mg/kg/day) and on days 3 to 5 (1 mg/kg/day). Evaluation included body weight, oral intake, and histology. Results: For the comparison of the change of body weight between the rhEGF group and the no rhEGF group, a statistically significant difference was observed in the rhEGF group for the 5 days after day 3 of. the experiment. The rhEGF group and no rhEGF group had reduced food intake until day 5 of the experiment, and then the mice demonstrated increased food intake after day 13 of the of experiment. When the histological examination was conducted on day 7 after treatment with cisplatin and radiation, the rhEGF group showed a focal cellular reaction in the epidermal layer of the mucosa, while the no rhEGF group did not show inflammation of the oral mucosa. Conclusion: These findings suggest that rhEGF has a potential to reduce the oral mucositis burden in mice after treatment with cisplatin and radiation. The optimal dose, number and timing of the administration of rhEGF require further investigation.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.44 no.1
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• pp.56-63
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• 2007

In this paper, an eye tracking method is presented using a neural network (NN) and mean-shift algorithm that can accurately detect and track user's eyes under the cluttered background. In the proposed method, to deal with the rigid head motion, the facial region is first obtained using skin-color model and con-nected-component analysis. Thereafter the eye regions are localized using neural network (NN)-based tex-ture classifier that discriminates the facial region into eye class and non-eye class, which enables our method to accurately detect users' eyes even if they put on glasses. Once the eye region is localized, they are continuously and correctly tracking by mean-shift algorithm. To assess the validity of the proposed method, it is applied to the interface system using eye movement and is tested with a group of 25 users through playing a 'aligns games.' The results show that the system process more than 30 frames/sec on PC for the $320{\times}240$ size input image and supply a user-friendly and convenient access to a computer in real-time operation.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.3
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• pp.219-227
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• 2005

Purpose: Abnormalities in the p53 gene are regarded as the most consistent genetic abnormalities detected in head and neck squamous cell carcinogenesis. Two new members of the p53 gene family, p73 and p63 have recently been identified. They share considerable sequence homology with p53 in the transactivation, DNA binding, and oligomerization domains, indicating possible involvement in carcinogenesis. Disruption of the homeostatic balance between proliferation and apoptosis is widely believed to contribute to human oral carcinogenesis. The aim of this study was to analyze expression of p63 in squamous cell carcinogenesis and to compare with immunochemical markers representing cell proliferation and apoptosis. Materials and Methods: Using the Syrian hamster oral cancer model, the fraction of apoptotic (apoptotic index-AI), proliferating (mitotic index-MI) and p63 expressing keratinocytes were examined at normal, dysplastic and malignant oral epithelium using the TUNEL assay, PCNA and p63 immunostaining. Results: p63 significantly increased between normal and dysplastic epithelium and between dysplastic and malignant epithelium. PCNA significantly increased between normal and dysplastic epithelium and between normal and malignant epithelium. However, increase between dysplastic and malignant epithelium, though still increasing, was not statistically significant. The percentage of TUNEL positive cells increased from normal to dysplastic epithelium and returned to normal keratinocyte level in the malignant epithelium. However, differences between tissue types were not significant. The ratio of MI:AI increased significantly only in the dysplastic-malignant epithelial transition. The increase of p63 expression closely reflected the change in the MI:AI ratio during oral carcinogenesis. Conclusion: The p63 may be associated with the regulation of epithelial proliferation and apoptosis in DMBA-induced hamster buccal pouch squamous cell carcinogenesis. Further study is required to investigate which p63 isoforms are involved in hamster buccal pouch carcinogenesis.

• The Journal of Natural Sciences
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• v.14 no.1
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• pp.123-138
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• 2004

This study was to investigate the planting arrangement of ornamental trees and shrubs that leads to an appropriate, type of templescape. Temples sampled for this study were Woljonsa, Sineunsa, Sinreugsa and Mitasa which fall all under the category of the level land. The results obtained were as follows : Open space of Daewoongjeon in all temples, a main Sanctuary among temple buildings, where Buddha is enshrined in, we could not find any kinds of trees/shrubs to be planted. But tere were Acer mono, Acer planmatum, Crataegus pinnatifidam Raododendron poukhanense, Texus cuspidata and Buxus mincrophylla to be planted, before Jeokkwangjeon, in which Buddha is exceptionally enshrined. In Geugragjeon of both temples of Sinheunsa and Sinreugsa, and Elysium building and Muryangsujeon of Woljeongsa temple, an immeasurable bliss building, in which an Amitabha is enshrined. was Taxus cuspidata planted numerously found. Particularly, Josadang, Muryangsujeon and Samsungkag of Woljeongsa temple commonly had Sciadopiys verticillata, which is known as one of Japanese-favorite trees. Syinga oblata Lindaley was also observed at Jeokkwangjeon of Woljeongsa temple and Keungnakjon of Sinheungsa temple, and Vidurnun opulus var. calvesvens, a symbolic flower tree imaging Buddha's head, was planted in Myungboojeon of Sinheungsa temple and Keugnakjeon of Sinreugsa temple. Juniperus chinensis which could be observed in both temples Sinheunsa and Sinreugsa was well arranged enough to be easily captured by human's eyes. In terms of templescape that might be considered in templescape, the correlation between trees/shrubs and temple buildings was thoroughly discussed. And, with the results obtained through precise studies, we presented here in this paper newly designed model of templescape in level land buddhist temples which is possibly applied for planting and arrangement of trees or/and shrubs.

• Journal of the Korean Society of Radiology
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• v.6 no.5
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• pp.365-371
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• 2012

The radiation therapy treatment technique is developed from 3D-CRT, IMRT to Tomotherapy. and these three technique was most widely using methods. We find out a comparison normal tissue doses and tumor dose of 3D-CRT, IMRT(Linac Based), and Tomotherapy on Head and Neck Cancer. We achieved radiological image used the Human model phantom (Anthropomorphic Phantom) and it was taken CT simulation (Slice Thickness : 3mm) and GTV was nasopharngeal region and PTV(including set-up margin) was GTV plus 2mm area. and transfer those images to the radiation planning system (3D-CRT - ADAC-Pinnacle3, Tomotherapy - Tomotherapy Hi-Art System). The prescription dose was 7020 cGy and measuring PTV's dose and nomal tissue (parotid gland, oral cavity, spinal cord). The PTV's doses was Tomotherapy, Linac Based - IMRT, 3D-CRT was 6923 cGy, 6901 cGy and 6718 cGy its dose value was meet TCP because its value was up to the 95% based on 7020 cGy, Nomal tissue (parotid gland, oral cavity, spinal cord) was 1966 cGy(Tomotherapy), 2405 cGy(IMRT), 2468 cGy(3D-CRT)[parotid gland], 2991 cGy(Tomotherapy), 3062 cGy(IMRT), 3684 cGy (3D-CRT)[oral cavity], 1768 cGy(Tomotherapy), 2151 cGy(IMRT), 4031 cGy(3D-CRT)[spinal cord] its value did not exceeded NTCP. All the treatment techniques are equated with tumor and nomal tissue doses. The 3D-CRT was worse than other techniques on dose distribution, but it is reasonable in terms of TCP and NTCP baseline Tomotherapy, IMRT -dose distribution was relatively superior- was hard to therapy to claustrophobic patients and patients with respiratory failure. Particularly, in case on Tomotherapy, it take MVCT before treatment so dose measurement will be unnecessary radiation exposure to patients. Conclusion, Tomotherapy was the best treatment technique and 2nd was IMRT, and 3rd 3D-CRT. But applicable differently depending on the the patient's condition even though dose not matter.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.5
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• pp.535-543
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• 2008

Purpose: The objective of this study was to compare the bonding characteristics of a new self-adhesive resin cement to dentin, which does not require bonding and conditioning procedure of the tooth surface, and conventional resin cement. The effect of phosphoric acid etching prior to application of self-adhesive resin cement on the shear bond strength was also evaluated. Material and methods: Fortyfive non-carious human adult molars extracted within 6 months were embedded in chemically cured acrylic resin. The teeth were ground with a series of SiC-papers ending with 800 grit until the flat dentin surfaces of the teeth were exposed. The teeth were randomly divided into 3 experimental groups. In group 1, self-adhesive resin cement, RelyX Unicem (3M ESPE, Seefeld, Germany) was bonded without any conditioning of teeth. In group 2, RelyX Unicem was bonded to teeth after phosphoric acid etching. For group 3, Syntac Primer (Ivoclar Vivadent AG, Schaan, Liechtenstein) was applied to the teeth before Syntac adhesive (Ivoclar Vivadent AG, Schaan, Liechtenstein) and Helibond (Ivoclar Vivadent AG, Schaan, Liechtenstein) followed by conventional resin cement, Variolink II (Ivoclar Vivadent AG, Schaan, Liechtenstein). To make a shear bond strength test model, a plastic tuble (3 mm diameter, 3 mm height) was applied to the dentin surfaces at a right angle and filled it with respective resin cement, and light-polymerized for 40 seconds. All the specimens were stored in distilled water at $37^{\circ}C$ for 24 hours before test. Universal Testing Machine (Z020, Zwick, Ulm, Germany) at a cross head speed of 1 mm/min was used to evaluate the shear bond strength. The failure sites were inspected under a magnifier and Scanning Electron Microscope. The data was analyzed with One way ANOVA and Scheffe test at ${\alpha}$= 0.05. Results: (1) The shear bond strengths to dentin of RelyX Unicem was not significantly different from those of Variolink II/Syntac. (2) Phosphoric acid etching lowered the shear bond strength of RelyX Unicem significantly. (3) Most of RelyX Unicem and Variolink II showed mixed fractures, while all the specimens of RelyX Unicem with phosphoric acid etching demonstrated adhesive failure between dentin and resin cement. Conclusion: Shear bond strength to dentin of self-adhesive resin cement is not significantly different from conventional resin cement, and phosphoric acid etching decrease the shear bond strength to dentin of self-adhesive resin cement.