• Archives of Plastic Surgery
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• v.51 no.5
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• pp.480-486
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• 2024

Many failures in total or subtotal nasal reconstruction result from an underestimation of the amount of skin required for an adequate result, especially for sufficient lining. Such planning errors usually lead to poor results, with exposure of structural grafts, infection, scar retraction, airway obstruction, and finally loss of projection and shape of the reconstructed nose. Reconstruction options for cases in which previous attempts have failed are always limited, as well as in cases of trauma or burns affecting the soft tissues of the forehead and face. In such complex situations, one may employ free flaps or tissue expansion, but such resources may not be always available. We describe a technique indicated for salvage surgeries in patients whose previous nasal reconstructions have failed, allowing a generous amount of tissue transfer for the nasal region. The technique combines the use of supraclavicular and submental flaps, with simple execution, not requiring microsurgical skills or devices such as tissue expanders. Done in three stages, the described technique provides enough skin for a total nasal reconstruction. The final result is obtained after subsequent refinements, and the total number of procedures is equivalent to when more sophisticated techniques are employed, such as tissue expansion or microsurgery.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.1
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• pp.8-15
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• 2018

New methodology for probabilistic reliability based grid expansion planning of HVDC in power system including Wind Turbine Generators(WTG) is developed in this paper. This problem is focused on scenario based optimal selection technique to decide best connection bus of new transmission lines of HVDC in view point of adequacy reliability in power system including WTG. This requires two kinds of modeling and simulation for reliability evaluation. One is how is reliability evaluation model and simulation of WTG. Another is to develop a failure model of HVDC. First, reliability evaluation of power system including WTG needs multi-state simulation methodology because of intermittent characteristics of wind speed and nonlinear generation curve of WTG. Reliability methodology of power system including WTG has already been developed with considering multi-state simulation over the years in the world. The multi-state model already developed by authors is used for WTG reliability simulation in this study. Second, the power system including HVDC includes AC/DC converter and DC/AC inverter substation. The substation is composed of a lot of thyristor devices, in which devices have possibility of failure occurrence in potential. Failure model of AC/DC converter and DC/AC inverter substation in order to simulate HVDC reliability is newly proposed in this paper. Furthermore, this problem should be formulated in hierarchical level II(HLII) reliability evaluation because of best bus choice problem for connecting new HVDC and transmission lines consideration. HLII reliability simulation technique is not simple but difficult and complex. CmRel program, which is adequacy reliability evaluation program developed by authors, is extended and developed for this study. Using proposed method, new HVDC connected bus point is able to be decided at best reliability level successfully. Methodology proposed in this paper is applied to small sized model power system.

• Journal of Internet Computing and Services
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• v.24 no.5
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• pp.1-7
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• 2023

This paper proposes a small cell resource partitioning allocation method to solve interference to machine type communication devices (MTCD) and improve performance in 5G heterogeneous networks (HetNet) where macro base station (MBS) and many small cell base stations (SBS) are overlaid. In the 5G HetNet, since various types of MTCDs generate data traffic, the load on the MBS increases. Therefore, in order to reduce the MBS load, a cell range expansion (CRE) method is applied in which a bias value is added to the received signal strength from the SBS and MTCDs satisfying the condition is connected to the SBS. More MTCDs connecting to the SBS through the CRE will reduce the load on the MBS, but performance of MTCDs will degrade due to interference, so a method to solve this problem is needed. The proposed small cell resource partitioning allocation method allocates resources with less interference from the MBS to mitigate interference of MTCDs newly added in the SBS with CRE, and improve the overall MTCD performace using separating resources according to the performance of existing MTCDs in the SBS. Through simulation results, the proposed small cell resource partitioning allocation method shows performance improvement of 21% and 126% in MTCDs capacity connected to MBS and SBS respectively, compared to the existing resource allocation methods.

• International Commerce and Information Review
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• v.19 no.1
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• pp.99-126
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• 2017

The Indonesian e-commerce market has grown significantly due to sustained economic growth, middle class growth, rapid increase in Internet and SNS users, and increase in accessibility of mobile broadband services. In particular, consumers' online shopping through mobile and SNS has been increasing rapidly based on the expansion of the popularity of smart phone devices. This research suggested the strategies for expanding exports of Indonesia through e-commerce platform to the Korean firms, with deep analysis of the current status and features, problems, cases, and implications etc. of Indonesia's e-commerce market. As an export expansion strategy utilizing Indonesia's e-commerce platform, this study showed the Korean firms have to build a local online distribution network, establish a logistics & delivery and payment system, acquire Halal certification for Muslim market, carry out the in-depth market research, actively implement Hanryu marketing strategy, develop a creative product, set up market segmentation strategies, and develop SNS mobile marketing.

• Journal of Korean Library and Information Science Society
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• v.30 no.1
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• pp.193-217
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• 1999

This study is intended to find out the possible ways for the expansion of Library Finance. With this necessity, it is indicated three sources, such as governmental. fund from other endowments, public donation, which is stated as the subsidy sources in the 'Library Law', and issuing lotteries as well. Firstly, it is suggested collecting governmental funds, included in budget sheet every year, to the amount of a ten billion won. Secondly, it is indicated the ways to collect funds to the amount of a five billion won respectively from other endowments, such as Korea Raising Association Fund under the jurisdiction of the Minister of Culture and Tourism, Information Promotion Fund, on the basis of statistical data, materials of inspection of the administration, and materials released by the government. Third device is to collect funds over a five billion won every year through public donation and lottery. This study is indicated that three devices to raise the library fund for the expansion of Library Finance to the amount of a hundred and twenty billion won in total as mentioned above.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.28 no.4
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• pp.461-480
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• 2017

The purpose of this research is to explore young adults (YA)' perceptions, use, and needs of public libraries, as well as to find out how to make effective YA sections within public libraries. Two public libraries with separate YA sections were selected and a total of 126 YA users participated in the survey. The survey showed 86.5% of participants used the YA section and the main reasons for use were reading for leisure, study area use, and seeking information for school assignments. 64.8% of participants agreed that separate YA sections are needed at public libraries. The areas most in need of improvement were expansion of seats of YA section, lack of digital devices, and expansion of group study and meeting spaces. This research highlights for space composition policy as YA's needs, creating a balanced environment for physical facilities, and YA oriented service. As well, a need for improved opening hours, and expansion of multi-use spaces for seats of the YA section.

• The Journal of the Convergence on Culture Technology
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• v.10 no.5
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• pp.453-458
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• 2024

If you are unable to get comfortable sleep to maintain and recover your health, it will cause a lot of disruption to your daily life. Among the intraoral devices used to resolve snoring, obstructive sleep apnea, bruxism, teeth clenching, and mouth breathing, which interfere with a comfortable sleep, devices that stabilize the lower jaw by moving it forward are a treatment that replaces surgical therapy and positive airway pressure. It is showing effect. During use of the device, a force is generated that causes the lower jaw to return to its original position, so a device that fixes it with screws, rubber bands, etc. is used. To see the effect of the device, you must bite your upper and lower teeth. In order to eliminate the inconvenience of having to stay closed while sleeping, the device is manufactured only in the upper jaw and creates a vertical guideway in the lingual embarasure of the lower jaw in the shape of a key & key way structure, allowing twisting movements and allowing forward and lateral movements. It is about the development of a device that has a blocking function that allows the mouth to be opened while wearing the device and has a function that solves sleep apnea by inducing airway expansion during sleep.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.5
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• pp.459-466
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• 2010

Alveolar distraction osteogenesis (ADO) has been regarded as an acceptable treatment for the alveolar bone deficiency. For ADO at anterior maxillary area, the vector should be oriented to forward and down-ward direction to get an adequate occlusion with mandibular teeth and to increase bone length and width for implant placement. However, the conventional commercial distraction devices for ADO are designed to allow mainly downward movement of alveolar segment, even though a forward movement can be obtained a little by controlling of inclination of device. To make ADO with controllable bidirectional vector possible, we used customized devices using self-manufactured ABDUL (Alveolar Bone Distractor Using Lag screw principle) and commercial orthodontic palatal expansion device ($Hyrex^{(R)}$). In all cases (n = 4), ADO could be performed successfully and dental implants were able to placed with adequate occlusion. We report the procedures, advantages and disadvantages of these methods.

• Journal of Electrical Engineering and Technology
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• v.8 no.5
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• pp.991-1001
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• 2013

Instead of building new substations or transmission lines, proper installation of flexible AC transmission systems (FACTS) devices can make the transmission networks accommodate more power transfers with less expansion cost. In this paper, the problem to maximize power system loadability by optimally installing two types of FACTS devices, namely static var compensator (SVC) and thyristor controlled series compensator (TCSC), is formulated as a mixed discrete-continuous nonlinear optimization problem (MDCP). To reduce the complexity of the problem, the locations suitable for SVC and TCSC installations are first investigated with tangent vector technique and real power flow performance index (PI) sensitivity factor and, with the specified locations for SVC and TCSC installations, a set of schemes is formed. For each scheme with the specific locations for SVC and TCSC installations, the MDCP is reduced to a continuous nonlinear optimization problem and the computing efficiency can be largely improved. Finally, to cope with the technical and economic concerns simultaneously, the scheme with the biggest utilization index value is recommended. The IEEE-14 bus system and a practical power system are used to validate the proposed method.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.3
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• pp.201-207
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• 2020

With the expansion in the use of DC power systems and increased need for system maintenance, the development of measurement devices for maintenance requires high stability. Of the different kinds of DC current measurement devices, the single-shot measurement device causes the input signal of the current measuring unit to initially generate a high inrush current. The high inrush current flows into the signal processor of the meter, shortening the life of the internal fuses and causing failure. Therefore, in this study, the I²t value for increasing the durability of the fuse is designed using the available wire diameter. Operating characteristics for 210~400% over-current of the rated current, which is relatively low over-current, are realized by the plating of low melting tin metal. As a result, a method of designing a fuse element for a DC power supply, which improves the safety of the DC current measurement device by blocking the failure caused by the inrush current, is presented.