• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.12
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• pp.94-105
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• 2003

OBS(Optical Burst Switching) networks which decouple the burst from its header has characteristic one-way reservation. Therefore, the fault of a fiber link may lead to the magnitude of burst loss. Since sending a header packet and using an offset time before the transmission of the corresponding burst. In this paper, we analysis a offset time based on the burst loss rate resulting from only link failure and by applying the restoration schemes in an optical burst switching networks. The simulation results in terms of the effect of a offset time is evaluated in our network model to verify that comparing the numerical analysis with simulation result. Finally, and through these results, We propose the new restoration scheme based on offset time considered Quality of Service.

• The Journal of Korean Academy of Prosthodontics
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• v.53 no.2
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• pp.144-149
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• 2015

To achieve an esthetic restoration, visualized information considering the facial aspect of patient is required. As for the reasons of esthetic failure, it could be explained by lack of communication and information such as horizontal, vertical and esthetic line. Therefore, it is important to deliver that the visualized information to dental technicians or other dentists for the success of esthetic treatment. This case report presents the process of visualizing esthetic information and designing the restoration using a digital diagnostic tool; Digital Smile Design.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.9
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• pp.1507-1515
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• 2008

It is essential for electric power companies to have a quick restoration system of the faulted pole transformers which occupy most of transformers to supply stable electricity. However, it takes too much time to restore it when a transformer is out of order suddenly because we now count on operator in investigating causes of failure and making decision of recovery methods. This paper presents the concept of 'Fault pattern analysis and Restoration prediction model using Data mining techniques’, which is based on accumulated fault record of pole transformers in the past. For this, it also suggests external and internal causes of fault which influence the fault pattern of pole transformers. It is expected that we can reduce not only defects in manufacturing procedure by upgrading quality but also the time of predicting fault patterns and recovering when faults occur by using the result.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.505-508
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• 2007

Usually, cut-slope is the term that call rock slope. Therefore, the cause of instability of cut-slope is influenced generally in lithological and structure geological qualities including weathering disintegration. Through the several case studies, we could confirm that stabilization countermeasure also should be based in geological properties.

• Transactions of Materials Processing
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• v.3 no.4
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• pp.427-439
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• 1994

The high temperature deformation behavior of $SiC_p/Al-Si$ composites and Al-Si matrix was studied by hot torsion test in a range of temperature from $270^{\circ}C$ to $520^{\circ}C$ and at strain rate range of $1.2{\times}10_{-3}~2.16{\times}10_{-1}/sec$. The hot restoration mechanisms for both matrix and composites were found to be dynamic recrystallization(DRX) from the investigation of flow curves and microstructural evolutions. The Si precipitates and SiC particles promoted DRX, and the peak strain$({\varepsilon}_p)$ of the composites was smaller than that of the matrix. Flow stresses of $SiC_p/Al-Si$ composites were found to be generally higher than the matrix, but the difference was quite small at higher temperature due to the decrease of capability of load transfer by SiC particles. With increasing temperature, failure strain of matrix and composites are inclined to increase, the increasing value of failure strain for the $SiC_p/Al-Si$ composites was small compared to that of matrix. The stress dependence of both materials on strain rate() and temperature(T) was examined by hyperbolic sine law, $\.{\varepsilon}=A_1[sinh({\alpha}{\cdot}{\sigma})]_n$exp(-Q/RT)

• Journal of the Korean Society of Environmental Restoration Technology
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• v.5 no.4
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• pp.19-30
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• 2002

The stability of slope using root-pile like to the reinforcements is affected by the interaction behavior mechanism of soil-reinforcements. Through the studying on the interaction in joint of its, therefore, the control roles can be find out in installed slope. In study, the stress level ratio based on the insert angle of installed reinforcements in soil used to numerical analysis, which was results from the duty direct shear test in Lab. The maximum shear strain variation on the reinforcements was observed at insert angle, which was approximately similar to the calculated angle based on the equation proposed by the Jewell. The elasto-plastic joint model on the contact area of soil-reinforcements was presumed, the reinforced soil assumed non-linear elastic model and the reinforcements supposed elastic model, respectively. The finite element analysis of assumed models was performed. The shear strain variation of non-reinforced state obtained by the FEM analysis including elasto-plastic joint elements were shown the rationality of general limit equilibrium analysis for the slope failure mode on driving zone and resistance zone, which based on the stress level step according to failure ratio. Through the variation of shear strain for the variation of inserting angle of reinforcements, the different mechanism on the bending and the shear resistance of reinforcements was shown fair possibility.

• Korean Journal of Ichthyology
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• v.32 no.3
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• pp.182-190
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• 2020

The endangered Pseudopungtungia tenuicorpa were reintroduced to the Jojongcheon Stream in the Hangang River 2011~2012 as part of the restoration project. Since then, the restoration project has been evaluated as a failure because the P. tenuicorpa were not collected from the discharge site 2014~2016. This study was conducted 2017~2019 to verify that the P. tenuicorpa restoration project failed. Six locations were selected, including the discharge site, and the fish collection method used skimming nets, cast nets, long bag set nets, and scuba diving. In the survey results, 13 individuals were collected in a 0.5 km section, including the discharge station. The P. tenuicorpa habitat was approximately at a water depth of 0.5 m to 2 m in run water flow with the boulders and rocks. The age of the collected P. tenuicorpa were 0+ to 3-years-old, and the generation alternation was occurring stably. Thus, the P. tenuicorpa restoration project was evaluated as partially-successful, as the P. tenuicorpa, re-introduced to the Jojongcheon Stream, settled in its habitat with stable generation alternation.

• Archives of Plastic Surgery
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• v.48 no.1
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• pp.49-54
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• 2021

Background Reconstruction after removal of a malignant tumor in the head and neck region is crucial for restoring tissue integrity, function, and aesthetics. We retrospectively analyzed patients who underwent intraoral reconstruction surgery using radial forearm free flaps (RFFF) and anterolateral thigh free flaps (ALT) at a single institution to provide more information supporting the choice of a reconstruction method after removal of head and neck cancer. Methods The charts of 708 patients who underwent head and neck reconstruction between 1998 and 2018 at the Department of Plastic and Reconstructive Surgery at our institution were retrospectively reviewed. Patients' age, sex, and history of radiation therapy, diabetes mellitus, and smoking were retrieved. The primary cancer site, types of defects, and complications were investigated. Results Overall, 473 and 95 patients underwent reconstruction surgery with RFFF and ALT, respectively. RFFF was more often used in patients with cancers of the pharynx, larynx, esophagus, or tonsil, while ALT was more frequently used in patients with cancers of the mouth floor with tonsil or tongue involvement. The proportion of patients undergoing ALT increased gradually. Flap failure and donor site morbidities did not show significant differences between the two groups. Conclusions RFFF and ALT flaps resulted in similar outcomes in terms of flap survival and donor site morbidity. ALT can be an option for head and neck reconstruction surgery in patients with large and complex defects or for young patients who want to hide their donor site scars.

• Journal of the Korean Geosynthetics Society
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• v.15 no.4
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• pp.105-115
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• 2016

This paper describes a restoration of retaining wall, which was collapsed by rainfall. The failure causes was analyzed by field case, and then the countermeasure was suggested. The failure causes confirmed that observance of design and construction criteria was insufficient. It also was the climate condition like a rainfall and inappropriate construction management. The stability analysis for retaining wall, soil improvement and reinforced earth wall was conducted to confirm validity of the countermeasure. The analysis results showed that the suggested construction method satisfied in required safety factors. Therefore, it should be secured the stability of the structure based on the application of appropriate design method and construction management, when structure was constructed.

• The Journal of the Korean bone and joint tumor society
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• v.2 no.1
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• pp.101-105
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• 1996

Prosthetic reconstruction of musculoskeletal defects about the knee for tumor has many advantages, particularly the maintenance of motion and immediate functional restoration. But, prosthetic reconstruction has inherent limitations in terms of long-term durability. The authors have reported here a patient who had mechanical failure at 61 months later following use of a modular resection system to reconstruct the segmental defect of proximal tibia in osteosarcoma. In this case, another technique of extensor mechanism reconstruction using Achilles tendon allograft was attempted. Because of the concerns involving durability of tumor prosthesis, increased emphasis has to be placed on innovation in prosthetic design.