• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.25 no.2
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• pp.297-308
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• 1995

This study was designed to measure the absorbed dose to organs of special interest from full mouth with intraoral film(l4 films) and to compare the five periapical techniques. Thermoluminescent crystals(TLD-100 chip) were located in brain, orbit, bone marrow of mandibular ramus, bone marrow of mandibular body, bone marrow of 4th cervical spine, parotid gland, submandibular gland and thyroid gland. X -ray machine was operated at 70kVp and round collimating film holding device(XCP) and rectangular collimating film holding device(Precision Instrument) were used. The distance from the X-ray focus to the open end of the collimator was 8 inch, 12 inch and 16 inch. The results were as follows : 1. The absorbed dose was the highest in bone marrow of mandibular body(5.656mGy) and the lowest in brain (0.050mGy). 2. Generally, the lowest absorbed dose was measured from 16 inch cylinder, rectangular collimating film holding device with paralleling technique. But, in bone marrow of mandibular body and the floor of mouth, the highest absorbed dose was measured from 12 inch cylinder, rectangular collimating film holding device with paralleling techniques. 3. Comparing of five intraoral radiographic techniques, it was appeared statistically significant reduction of the absorbed doses measured with rectangular collimating film holding device compared to XCP film holding device (P<0.05). 4. No statistically significant reduction in the absorbed dose was found as cylinder length was changed(P>0.05).

• Journal of Periodontal and Implant Science
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• v.30 no.4
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• pp.793-803
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• 2000

Procedures for treatment of molar furcation invasion defects range from open flap debridement, apically repositioned flap surgery, hemisection, tunneling or extraction, to regenerative therapies using bone grafting or guided tissue regenerative therapy, or a combination of both. Several clinical evaluations using regenerative techniques have reported the potential for osseous repair of treated furcation invasions. Regenerative treatment of maxillary molars are more difficult due to the multiple root anatomy and multiple furcation entrances therefore, purpose of this study was to evaluated histologically self-curing glass-ionomer cement and light-curing glass-ionomer cement as a barrier in the treatment of a bi-furcated maxillary premolar. Five adult beagle dogs were used in this experiment. With intrasulcular and crestal incision, mucoperiosteal flap was elevated. Following decortication with 1/2 high speed round bur, degree II furcation defect was made on maxillary third(P3), forth(P4) and fifth(P5) premolar. 2 month later experimental group were self-curing glassionomer cement and light-curing glassionomer cement. After 4, 8 weeks, the animals were sacrificed by vascular perfusion. Tissue block was excised including the tooth and prepared for light microscope with Gomori's trichrome staining. Results were as follows. 1. In all experiment group, there were not epithelial down growth and glass ionomer cement were encapsulated connective tissue. 2. In 4 weeks experiment I group slighly infiltrated inflammatory cells but not disturb the new bone or new cementum formation. 3. In 8 weeks, experiment groups I, II were encapsulated fine connective tissue. 4. Therefore glass-ionomer cement filling to the grade III maxillary furcations with multiple root anatomy and multiple furcation entrances were possible clinical methods and this technique is useful method for Maxillary furcation involvement.

• Archives of Craniofacial Surgery
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• v.13 no.1
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• pp.63-67
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• 2012

Purpose: Lipogranuloma is the reaction of adipose tissue to various oils, paraffin, and other hydrocarbons injected into subcutaneous tissue for cosmetic or other reasons. The authors experienced a case of sclerosing lipogranuloma on the nasal dorsum. Methods: A 42-year-old female, without a history of the injection of any foreign materials, was admitted on our hospital for a painless, irregular, and firm mass located on her nasal dorsum with step-off deformity. It was considered that the mass had developed after augmentation rhinoplasty. The size of mass had been increased after closed reduction of nasal bone fracture. On April 2011, under general anesthesia, the mass was removed by open rhinoplasty technique. In addition, a pathologic examination was performed. After the mass extirpation, dermofat graft was performed for the correction of depression deformity. Results: The histopathological findings demonstrated a Swiss cheese pattern with variably-sized vacuoles, which corresponded to lipid removed with tissue processing, and variable foreign body giant cell reaction, fat necrosis, and hyalinized fibrous tissue. The pathologic diagnosis is lipogranuloma replacing nasalis muscle. It has been considered that sclerosing lipogranuloma is caused by nerve injury during augmentation rhinoplasty and the ointment used after the closed reduction of nasal bone fracture, which infiltrated through the injured mucosa. Conclusion: During the treatment of rhinoplasty or nasal bone fracture, the nerve injury or the ointment use can lead to lipogranuloma. Therefore, careful dissection for avoidance of the nerve injury and limited use of ointment seems to be helpful in decreasing incidence of lipogranuloma.

• Archives of Craniofacial Surgery
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• v.13 no.1
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• pp.22-28
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• 2012

Purpose: In accordance to an increased interest in facial appearance and the popularization of computed tomography scanning, the number of diagnosis and treatment of blowout fractures has been increased. The purpose of this article is to review pure blowout fracture surgery through transconjunctival incision focusing on complications and their management. Methods: In this retrospective study, 583 patients, who had been treated for pure blowout fracture through transconjunctival incision from 2000 to 2009, were evaluated. Their hospital records were reviewed according to their sex, age, fracture site, preoperative presentations, time interval between trauma and surgery, and postoperative complications. Results: According to postoperative follow-up results, there were early complications that included wound dehiscence and infection (0.2%), hematoma (insomuch as extraocular movement is limited) (0.7%), lacriminal duct injury (0.5%), and periorbital nerve injury (0.7%). In addition, there were late complications that lasted more than 6 months, that included persistent diplopia (1.7%), extraocular movement limitation (0.9%), enophthalmos (1.0%), periorbital sensation abnormalities (1.0%), and entropion (0.5%). Conclusion: We propose the following guidelines for prevention of postoperative complications: layer by layer closure; bleeding control with the epinephrine gauzes, Tachocomb, and Tisseel; conjunctival incision 2 to 3 mm away from punctum; avoidance of excessive traction; performing surgical decompression and high dose corticosteroid therapy upon confirmation of nerve injury; atraumatic dissection and insertion of Medpor Barrier implant after securing a clear view of posterior ledge; using Medpor block stacking technique and BioSorb FX screw fixation; performing a complete resection of the anterior ethmoidal nerve during medial wall dissection; and making an incision 2 to 3 mm below the tarsal plate.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.248-251
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• 2016

This thesis has discussed how to recognize and convert raised letters on tire to data and collect such data. Unlike the existing recognition system, the system presented by this thesis recognizes raised letters on tire through detecting letters after converting the Kinect camera image into image data in the preprocessing stage. After then, numbers and letters are analyzed through image improvement by use of binary images, noise filter, etc. In the recognition stage, letter distinction is used and raised letters on tire are recognized 100% through correction of errors by way of the correction algorithm for tire data recognition errors. In this paper it will be the development of a method of recognizing characters and the tire technology. Although there are many ways to the already recognized characters, Tire characters requires a technique different from the more general character recognition. For this reason and to develop additional technical methods and algorithms for character recognition.

• The Transactions of the Korea Information Processing Society
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• v.4 no.3
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• pp.767-774
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• 1997

A procedure presented in this paper greerates test squences to check the conformity of an implementation wihh a protocol specification which is moedled as a determinstic fimite state machine(FSM).We proposed a tech-nique to determine a minium-cost tour of the transition graph of the FSM..The technique using Multiple UIO and Shortest Path(MUSP) sabes the cost 1-9% over MUIO and directly, derive a symertric test graph from an FSM graph From this fact, we proposed a tecuque using Multiple Sate Suganture(MUSS) to solve an open issue that the multiple UIO assignment may not minimize the lengy of the tour.In this paper, the proposed techique is also, applied to generate a synchronizable test wequence.And the result shows that the techique using MUSP anhd MUSS saves the cost 7-29% and 7-42% over the previous approach using MUIO, respect-ively.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.7A
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• pp.515-522
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• 2009

In this paper, a novel transmission scheme with spatial modulation is proposed for coded orthogonal frequency division multiplexing (OFDM). The multiple-input multiple-output (MIMO) technique, so-called spatial modulation (SM), divides input data into antenna index and data signals, transmitting data signals through the specific antenna chosen by the antenna index. In order to retrieve data stream at the receiver, SM needs to detect the antenna index which means that data signals are transmitted via a certain antenna. For this reason, it should be guaranteed that channel matrix is orthogonal. For the real environment, a MIMO channel has difficulty in maintaining orthogonality due to spatial correlation. Moreover, the receiver of the conventional SM is operated by hard decision, so that this scheme has a limit to be adopted for practical systems. Therefore, soft-output demappers for the conventional and proposed schemes are derived to detect antenna index and data stream by soft decision, and a novel transmission scheme combined with spatial modulation is proposed to improve the bit error rate (BER) performance of the conventional scheme.

• Korean Journal of Construction Engineering and Management
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• v.4 no.3 s.15
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• pp.137-145
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• 2003

The project control system based on the actual values of three objects shall be operated continuously in a timely manner. For collecting/tracking accurate actual performance data, a reasonable basis of measuring work performance and its related measuring methods are needed. Therefore, this research proposes a method of developing and operating the construction progress measurement system. The problem of the conventional method is the difficulty to construct control accounts and to define the basis of measuring the performance of each control account. Therefore, this research proposes the preferable, formal methodology that produces the progress value of the smallest work unit by surveying the installed quantities and estimates percent complete of groups of works or entire project by earned value concept. This research in connection with the hereafter research of the weight value of control accounts will contribute to apply in practice and to develop the scientific construction management technique in the construction industry. Further researches how to trend and forecast the project using the measured progress value are recommended for putting the prosed system of this research to practical use.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.1
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• pp.88-97
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• 1996

The metallization is the key to determining cell costs, cell performance, and system reliability. Screen printing technology suffers from several limitations affecting mainly the front grid. The buried contact solar cell (BCSC) was specifically desinged to be compatible with low cost, mass production techniques and avoid the conventional metallization problem. By using electroless plating technique, we performed this metallization inexpensively and reliably. This paper presents the details of the optimization procedure of metallization schemes on laser grooved cell surfaces. Commercially available Ni, Cu and Ag plating solutions were applied for the cell metallization. The application of those solutions on the buried contact front metallization has resulted in an cell efficiency of 18.8%. The cell parameters are an open circuit voltage of 651 mV, short circuit current density of 37.1 mA/$\textrm{cm}^2$, and fill factor of 77.8 %. The efficiency of over 18 % was achieved in the above 90% of the batch.

• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.3
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• pp.137-147
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• 2012

Recently, floating green algae (FGA) in open oceans and coastal waters have been reported over wide area, yet accurate detection of these using traditional ground based measurement and chemical analysis in the laboratory has been difficult or even impossible due to the lack of spatial resolution, coverage, and revisit frequency. In contrast, spectral reflectance measurement makes it possible to quickly assess the chlorophyll content in green algae. Our objectives are to investigate the spectral reflectance of the FGA observed in the Yellow Sea and to develop a new index to detect FGA from satellite imagery, namely floating green algae index (FGAI), which uses relatively simple reflectance ratio technique. The Moderate Resolution Imaging Spectroradiometer (MODIS) and Geostationary Ocean Color Imager (GOCI) satellite images at 500m spatial resolution were utilized to produce FGAI which is defined as the ratio between reflectance at 860nm and 660nm bands. Both FGAI results yielded reasonable green algae detection at the regional scale distribution. Especially houly GOCI observations can present more detaield information of FGAI than low-orbit satellite.