• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.2
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• pp.189-191
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• 2001

Objective : The objective of this study was to determine which forms of iliac cancellous bone grafts better restore alveolar clefts. Study design : Forty consecutive patients who required a unilateral alveolar cleft graft were studied. Group I (20 patients) had reconstruction with iliac cancellous particulate bone grafts and group II (20 patients) had reconstruction with iliac cancellous block bone grafts. The two groups were evaluated radiographically and clinically. Results : The group with the block bone grafts showed less postoperative problems and better incorporation of the bone graft than the group with the particulate grafts. Conclusion : Surgical reconstruction of alveolar process defects in patients with alveolar cleft using iliac cancellous block bone is a more reliable method than particulate bone grafts both for closing the oronasal fistula and for building interalveolar septal height.

• Korean Journal of Head & Neck Oncology
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• v.11 no.2
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• pp.167-172
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• 1995

Pharyngocutaneous fistula(PCF) is one of the complications following total laryngectomy in laryngeal and hypopharyngeal cancer. Fistula lead to delayed wound healing, more serious complications such as carotid blow-out, prolonged hospitalization, significant patient morbidity and occasional mortality. Identification of patients at high risk for fistula formation, appropriate preventive measures, and appropriate management are the head and neck surgeon's responsibility. So we analyzed the clinical data of pharyngocutaneous fistula which was developed after total laryngectomy. Following results were obtained: 1) Occurrence of PCF increases with salvage surgery compared to curative surgery. 2) Early detection and effective management of PCF are the key factors to decreasing the hospitalization period. 3) Constructing a pharyngostoma seems to be an ideal method of preventing dangerous complications and ultimately closing the fistula. 4) Simultaneous reconstruction is necessary in the high risk group.

• International Journal of Naval Architecture and Ocean Engineering
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• v.5 no.4
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• pp.493-501
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• 2013

Taking into account the increasingly stringent legislation on emissions from marine engines, this work aims to analyze several internal engine modifications to reduce $NO_x$ (nitrogen oxides) and other pollutants. To this end, a numerical model was employed to simulate the operation cycle and characterize the exhaust gas composition. After a preliminary validation process was carried out using experimental data from a four-stroke, medium-speed marine engine, the numerical model was employed to study the influence of several internal modifications, such as water addition from 0 to 100% water to fuel ratios, exhaust gas recirculation from 0 to 100% EGR rates, modification of the overlap timing from 60 to $120^{\circ}$, modification of the intake valve closing from 510 to $570^{\circ}$, and modification of the cooling water temperature from 70 to $90^{\circ}C$. $NO_x$ was reduced by nearly 100%. As expected, it was found that, by lowering the combustion temperature, there is a notable reduction in $NO_x$, but an increase in CO (carbon monoxide), HC (hydrocarbons) and consumption.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.3
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• pp.597-601
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• 1997

This paper presents improper use of latex-elastic ring in movement of teeth and its consequence. Simple orthodontic movement of teeth including closure of diastema may be achieved by the use of simple method with fixed or removable appliance associated with latex-elastic ring. But, if it is used alone, it acts as a local irritant and then produces localized periodontitis. In case of localized periodontitis resulting from latex-elastic ring, diagnosis is difficult because the patient is usually unaware of the presence of the rings on the roots of the involved teeth and because the ring is not probed and is radiolucent and therefore not discernible radiographically and clinically. Occasionally, surgery is requred for the detection. This case emphasizes the necessity that the use of latex-elastic ring in closing diastema should be accompanied with removable or fixed appliance as well as close professional supervision. Its use without adequate provision for stabilization or retention on the crowns of teeth results in destruction of periodontal support and the teeth may be lost.

• Journal of the Korean Ceramic Society
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• v.43 no.4 s.287
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• pp.199-202
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• 2006

In this study, SiC whiskers were grown on a porous SiC diesel particulate filter for nanoparticle filtering. To grow the whiskers at the inner pore without closing the pores, we used chemical vapor infiltration with a solution source and a dilute. As the deposition time increased, the whiskers grew and formed a network structure. After 180 min of deposition, the mean diameter of the whiskers was 174 nm and the compressive strength was 58.4 MPa. The pores shrank from $10{\mu}m\;to\;0.4{\mu}m$ and, because the whiskers filed the inner pores, the gradient of permeability decreased as the deposition time increased. However, by using the network structure of whiskers deposited for 120 min and 180 min, we obtained a diesel particulate filter with pores of $0.98{\mu}m\;and\;0.4{\mu}m$, respectively. Furthermore, the filter shows better permeability than a porous body with pores of $1{\mu}m$. In short, by filtering the nanoparticulate materials, the network structure of whiskers improves the strength, reduces the pore size and minimizes the permeability drop.

• Journal of Nuclear Fuel Cycle and Waste Technology
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• v.1 no.1
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• pp.29-35
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• 2013

The United States Department of Energy (US DOE) is conducting research and development (R&D) activities under the Used Fuel Disposition Campaign (UFDC) to support storage, transportation, and disposal of used nuclear fuel (UNF) and wastes generated by existing and future nuclear fuel cycles. R&D activities are ongoing at nine national laboratories, and are divided into storage, transportation and disposal. Storage R&D focuses on closing technical gaps related to extended storage of UNF. Transportation R&D focuses on ensuring transportability of UNF following extended storage, and addressing data gaps regarding nuclear fuel integrity, retrievability, and demonstration of subcriticality. Disposal R&D focuses on identifying geologic disposal options and addressing technical challenges for generic disposal concepts in mined repositories in salt, clay/shale, and granitic rocks, and deep borehole disposal. UFDC R&D goals include increasing confidence in the robustness of generic disposal concepts, reducing generic sources of uncertainty that may impact the viability of disposal concepts, and developing science and engineering tools to support the selection, characterization, and licensing of a repository. The US DOE has also initiated activities in the Nuclear Fuel Storage and Transportation (NFST) Planning Project to facilitate the development of an interim storage facility and to support transportation infrastructure in the near term.

• The Journal of Advanced Prosthodontics
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• v.1 no.2
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• pp.102-106
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• 2009

STATEMENT OF PROBLEM. Screw loosening has been a common complication and still reported frequently. PURPOSE. The purpose of this study was to evaluate abrasion of the implant fixture and TiN coated abutment screw after repeated delivery and removal with universal measuring microscope. MATERIAL AND METHODS. Implant systems used for this study were Osstem and 3i. Seven pairs of implant fixtures, abutments and abutment screws for each system were selected and all the fixtures were perpendicularly mounted in liquid unsaturated poly-esther with dental surveyor. After 20 times of repeated closing and opening test, the evaluation for the change of inner surface of implant and TiN-coated abutment screw, and weight loss were measured. Mann-Whitney test with SPSS statistical software for Window was applied to analyze the measurement of weight loss. RESULTS. TiN-coated abutment screws of Osstem and 3i showed lesser loss of weight than non-coated those of Osstem and 3i (P < .05, Mann-Whitney test). CONCLUSION. Conclusively, TiN coating of abutment screw showed better resistance to abrasion than titanium abutment screw. It was concluded that TiN coating of abutment screw would reduce the loss of preload with good abrasion resistance and low coefficient of friction, and help to maintain screw joint stability.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.5
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• pp.483-488
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• 2006

Velopharyngeal function refers to the combined activity of the soft palate and pharynx in closing and opening the velopharyngeal port to the required degree. In normal speech, various muscles of palate & pharynx function as sphincter and occlude the oropharynx from the nasopharynx during the production of oral consonant sounds. Inadequate velopharyngeal function caused by neurologic disorder - cerebral apoplexy, regressive diseases - disseminated sclerosis, Parkinson's disease, congenital deformity - cleft palate, cerebral palsy and etc. may result in abnormal speech characterized by hypernasality, nasal emission and decreased intelligibility of speech due to weak consonant production. In our study, we constructed speech aids prosthesis - Speech bulb in the incomplete cleft palate VPI patient with hypernasality and assessed velopharyngeal function with nasometer which can evaluate the speech characteristics objectively.

• Smart Structures and Systems
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• v.24 no.2
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• pp.157-171
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• 2019

This study investigated the effects of the geometric parameters of superelastic shape memory alloy (SE SMA) fibers on the pullout displacement recovering and self-healing capacity of reinforced cementitious composites. Three diameters of 0.5, 0.7 and 1.0 mm and two different crimped lengths of 5.0 and 10.0 mm were considered. To provide best anchoring action and high bond between fiber and cement mortar, the fibers were crimped at the end to create spear-head shape. The single fiber cement-based specimens were manufactured with the cement mortar of a compressive strength of 84 MPa with the square shape at the top and a dog-bone shape at the bottom. The embedded length of each fiber was 15 mm. The pullout test was performed with displacement control to obtain monotonic or hysteretic behaviors. The results showed that pullout displacements were recovered after fibers slipped and stuck in the specimen. The specimens with fiber of larger diameter showed better displacement recovering capacity. The flag-shaped behavior was observed for all specimens, and those with fiber of 1.0 mm diameter showed the clearest one. It was observed that the length of fiber anchorage did not have a significant effect on the displacement recovery, pullout resistance and self-healing capacity.

• Annual Conference on Human and Language Technology
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• 2023.10a
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• pp.677-682
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• 2023

초거대 언어모델은 모델의 학습 없이 학습 예시만을 입력에 추가함으로써 목표하는 작업을 수행한다. 이런 방식은 상황 내 학습 (In-Context Learning, ICL)이라 불리며, 초거대 언어모델 활용의 사실상의 표준으로 사용되고 있다. 하지만 이러한 모델은, 환각현상 등 사용상의 한계가 발생하는 상황이 다수 발생한다는 연구 결과가 나오고 있다. 본 연구에서는 초거대언어모델을 한국어 작업에서 사용하는 경우, 매우 간단한 수준의 종결어미 변환만으로도 성능 편차가 매우 크게 발생함을 확인하였다. 우리는 이에 대한 분석을 통해, 학습 예시의 어체와 추론 대상의 어체의 변환에 따라 초거대언어모델의 효용성이 크게 변함을 발견하고 이에 대해 분석한다. 나아가 우리는 본 실험 결과를 바탕으로, 어체에 대한 일관성이 유지된 형태의 한국어 데이터 구축이 이루어져야 함을 제안한다.