• Restorative Dentistry and Endodontics
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• v.38 no.3
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• pp.160-166
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• 2013

This case report demonstrates an unnecessary endodontic treatment of teeth with florid cemento-osseous dysplasia (FCOD) due to a misdiagnosis as periapical pathosis and emphasizes the importance of correct diagnosis to avoid unnecessary treatment. A 30-year-old woman was referred to our institution for apicoectomies of the mandibular left canine and both the lateral incisors. The periapical lesions associated with these teeth had failed to resolve after root canal treatment over a 3-year period. Radiographic examinations revealed multiple lesions on the right canine, the second premolar, and both first molars as well as the anterior region of the mandible. Based on clinical, radiographic and histological evaluations, the patient condition was diagnosed as FCOD. The patient has been monitored for 2 years. To avoid unnecessary invasive treatment, accurate diagnosis is essential before treatment is carried out in managing FCOD.

• Journal of information and communication convergence engineering
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• v.20 no.3
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• pp.160-165
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• 2022

This paper proposes an efficient method of reconstructing interconnections when the terminals of each plane change in real-time situations where randomly divided planes are interconnected. To connect all terminals when the terminals of each plane are changed, we usually reconstruct the interconnections between all terminals. This ensures a minimum connection length, but it takes considerable time to reconstruct the interconnection for the entire terminal. This paper proposes a solution to obtain an optimal tree close to the minimum spanning tree (MST) in a short time. The construction of interconnections has been used in various design-related areas, from networks to architecture. One of these areas is an ad hoc network that only consists of mobile hosts and communicates with each other without a fixed wired network. Each host of an ad hoc network may appear or disappear frequently. Therefore, the heuristic proposed in this paper may expect various cost savings through faster interconnection reconstruction using the given information in situations where the connection target is changing.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.33 no.3
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• pp.160-165
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• 2022

The coronavirus disease 2019 (COVID-19) pandemic has taken a toll on human lives and health systems worldwide and is still affecting all medical practices years later. In particular, much medical staff had to sacrifice in areas where the medical system was overloaded in the early stages of the outbreak and the resulting shortage of medical resources. In the future, another pandemic disease seems to emerge, which should threaten otolaryngologists inevitably. It is necessary to understand viral aerosolization and practice recommendations for COVID-19. These can guarantee the most effective treatment for the patients during the pandemic and protect the safety of our medical staff and patients.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.70-70
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• 2022

Corchoropsis Siebold & Zucc. was traditionally included in Tiliaceae, however, several morphological characters and molecular phylogenetic studies supported that it was the member of Dombeyoideae (Malvaceae). It is used as compost, medicinal, and ornamental herbs. Out of total three species, two species and one variety, grow in Korea. Although it is an East Asian endemic genus, plastome data has not been defined. Here, we characterize the plastome sequences of C. tomentosa (160,093 bp) and C. tomentosa var. psilocarpa (160,724 bp). Corchoropsis encodes 78 protein-coding genes, 30 tRNAs, and four rRNAs with a pseudogene inf A. Phylogenetic study revealed that Tilioideae is sister of Dombeyoideae. This study will contribute to define the genome structures, phylogenetic, and evolutionary studies of the genus Corchoropsis.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.6
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• pp.472-477
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• 2009

This study was conducted to reclassify Bugog series based on the second edition of Soil Taxonomy : A Basic System of Soil Classification for Making and Interpreting Soil Surveys. Morphological properties of typifying pedon of Bugog series were investigated and physico-chemical properties were analyzed according to Soil Survey Laboratory Methods Manual. The typifying pedon of Bugog series has strong brown (7.5YR 4/6) loam Ap horizon (0~22 cm), brown (7.5YR 4/4) clay loam BAt horizon (22~41 cm), strong brown (7.5YR 4/6) silty clay loam Bt1 horizon (41~59 cm), strong brown (7.5YR 4/6) silty clay loam Bt2 horizon (59~78 cm), brown (7.5YR 4/4) silty clay loam Btx1 horizon(78~90 cm), and brown (7.5YR 4/4) Btx2 horizon(90~160 cm). That occurs on swale foot slope in area of mainly granite gneiss, granite, and schist rock materials. The typifying pedon has an argillic horizon from a depth of 22 to more than 160 cm and a base saturation (sum of cations) of less than 35% at 75 cm below the upper boundary of the fragipan. That can be classified as Ultisol, not as Alfisol. The pedon has udic soil moisture regime, and can be classified as Udult. That has a fragipan with an upper boundary within 100 cm of the mineral soil surface, and keys out as Fragiudult. Also that meets the requirements of Typic Fragiudult. That has 18% to 35% clay at the particle-size control section, and has mesic soil temperature regime. Bugog series can be classified as fine silty, mixed, mesic family of Typic Fragiudults, not as fine loamy, mixed, mesic family of Typic Fragiudalfs.

• Aerospace Engineering and Technology
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• v.7 no.2
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• pp.76-81
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• 2008

The vibration test system of satellite environment test dept. has been used successfully for the vibration tests of a majority of korean space programs. To meet the recent needs of large size test facility available for the vibrational tests of the huge launch vehicles and satellites, KARI have developed the large size multi-electromagnetic shaking system with $3{\times}3m$ head expander system. The new system will consist of three electromagnetic shakers which has 160 kN thrust force individually, and be able to sustain up to 8 tons test load and 300 kNm overturing moment. This paper describes the design components in the development process of multi-excitation shaker system.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.1
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• pp.160-169
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• 1987

Numerical simulation of the flow of upper convected Maxwell fluid through planar 4:1 contraction has been performed using type dependent difference apprximation of vorticity equation. For creeping flow assumption, the numerical convergence has been achieved up to much higher values of elasticity parameter than those obtained by conventional finite difference method. For non-vanishing Reynolds number flow, it is shown that the corner vortices disappear, which is in good qualitative agreement with extant experimental results. In doing so, spatial distributions of stream function, vorticity and stresses are considered in relation to change of type of vorticity.

• International Journal of Fluid Machinery and Systems
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• v.7 no.4
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• pp.160-173
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• 2014

Surge phenomena in multi-stage axial flow compressors were studied with attention to the frequency behaviors. A new parameter "volume-modified reduced surge frequency" was introduced, which took into consideration the essential surge process, i.e., emptying and filling of the working gas in the delivery plenum. The behaviors of the relative surge frequencies at the stall stagnation boundaries, compared with the corresponding duct resonance frequencies, have demonstrated the existence of two types of surges; i.e., a near-resonant surge and a subharmonic surge. The former, which has fundamentally a near-resonance frequency, occurs predominantly at the stall stagnation boundary for the short -and-fat plenum delivery flow-path and the long-and-narrow delivery duct flow-path, and possibly in the intermediate conditions. The latter, which has a subharmonic frequency of the fundamental near-resonant one and occurs mainly in the intermediate zone, is considered to be caused by the reduced frequency restricted to a limited range. In relation with those dimensionless frequencies at the stall stagnation boundary, the surge frequency behaviors in more general situations away from the boundaries could be estimated, though very roughly.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.160-160
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• 2008

In practical etching process, etch ant is sprayed on the metal-deposited panel through nozzles collectively connected to the manifold and that panel is usually composed of many PCB(printed circuit board)'s. The etching uniformity, the difference between individual PCB's on the same panel, has become one of most important features of etching process. In this paper, the prediction of nozzle trajectory has been performed by the combination of algebraic formula and numerical simulation. With the pre-determined geometrical factors of nozzle distribution, the trajectories of individual nozzles were predicted with the change of process operational factors such as panel speed, nozzle swing frequency and so on. As results, two dimensional distribution of impulsive force of etchant spray which could be considered as a key factor determining the etching performance have been successfully obtained. Though only qualitative prediction of etching uniformity have been predicted by the process developed in this study, the expansion to the quantitative prediction of etching uniformity is expected to be apparent by this study.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.2
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• pp.160-165
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• 2010

As the various industrial machinery has come into being by development of industrial technology, the productivity of the basic industrial machinery has improved. However, at the same time, noise from various industrial machinery disturbs the quiet environment. There are 35 kinds of the noise emission machinery defined in the noise and vibration control act according to the horse power and the number of machinery. These were classified in 1992, and the characteristics of the noise emission machinery may be different from the past one. So we need to investigate the characteristics of the noise emitted by machinery to control it rightly. We measured sound intensity of 32 noise emission machinery to calculate the sound power levels of those and investigated the characteristics of the sound power level of those according to the frequency. We found that the forging machine, concrete pipe and pile making machine, sawing machine, etc. are noisy. The generator, the concrete pipe and pile making machine, etc. emit the low frequency noise, but the molding machine, the stone cutter, the metal cutter, etc. emit the high frequency noise.