• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1855-1860
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• 2010

Electric vehicles have reached a new level of development with introductions by Chrysler, Ford, Honda and Toyota. Today's charging technology includes conductive and inductive charging systems. There are three standardized charging levels: Level 1: charging can be done from a standard, grounded AC 120V, 3-prong outlet available in all homes; Level 2: charging is at AC 240V, 40 amp charging station with special consumer features to make it easy and convenient to plug in and charge EVs at home or at an EV charging station; Level 3: a high-powered charging "fast charge" technology currently under development that will provide a charge in less than 15 minutes. The incoming AC power is converted to DC and stored in the vehicle's batteries. In this paper, we investigated the application of urban railway DC electric power for electric car charging system.

• Journal of Mechanical Science and Technology
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• v.20 no.5
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• pp.681-691
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• 2006

Nucleate boiling heat transfer for refrigerants, R113, and R113+wt4% ethanol mixture, an azeotropic mixture under electric field was investigated experimentally in a single-tube shell/ tube heat exchanger. A special electrode configuration which provides a more uniform electric field that produces more higher voltage limit against the dielectric breakdown was used in this study. Experimental study has revealed that the electrical charge relaxation time is an important parameter for the boiling heat transfer enhancement under electric field. Up to 1210% enhancement of boiling heat transfer was obtained for R113+wt4% ethanol mixture which has the electrical charge relaxation time of 0.0053 sec whereas only 280% enhancement obtained for R113 which has relaxation time of 0.97 sec. With artificially machined boiling surface, more enhancement in the heat transfer coefficient in the azeotropic mixture was obtained.

• Journal of Korean society of Dental Hygiene
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• v.13 no.1
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• pp.38-44
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• 2013

Objectives : This study is to dental knowledge and awareness of special education teachers. Methods : This study is conducted with a total of 244 special education teachers in Dae Gu, Gyeong Buk, Gyeong Nam, Bu San city from 1st April to 30th April, 2011. Results : More healthy state of oral health reflected higher point of oral health behavior. In the correlation among the oral health knowledge, behavior and education, higher oral health knowledge reflected higher oral health behavior. In the obstacle factors against oral health education, 41.0% was in the lack of professionalism and understanding of oral health education. The majority method for oral health education was regular teaching and the oral health in charge of education was school nurse 67.1%. The most important point for improvement for oral health class enabled was oral health recognition of teachers about the importance of education. Conclusions : For improving the oral health of the disabled, it is needed to develop the educational program or awareness of oral health monitoring like applying fluorine by special education teachers and parents, including the necessity of various oral health education development suitable for the special education school to make awareness in the importance and necessity of oral health.

• The Journal of the Korean dental association
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• v.17 no.11 s.126
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• pp.845-847
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• 1979

• Journal of the Korea Society of Computer and Information
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• v.26 no.6
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• pp.167-172
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• 2021

The objective of this study is to present the academic implications and developmental direction of the police assigned for special guard system through big data analysis on the objective and macroscopic viewpoint of the media. As research method, this study conducted the analysis on 'police assigned for special guard' and the analysis of related words that would visualize the keywords highly related to keyword trend and news. Also, after dividing the period into the 1990s, 2000s, and 2010s, the number of relevant articles in each period was drawn for understanding the flow. In the results of this study, the perception of media report of police assigned for special guard was about the recruitment of police assigned for special guard, and relevant events/accidents, which showed the coexistence of positive interest in the recruitment of police assigned for special guard and negative image of events/accidents related to police assigned for special guard. As a result, however, the necessity and demand for police assigned for special guard are increasing. Thus, the police assigned for special guard should be engaged in work after carefully thinking of its role in charge of ethical responsibility and safety as an axis for maintaining the national safety and social order.

• MALSORI
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• no.19_20
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• pp.29-32
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• 1990

The Arae Hangul wordprocessor is one of the most famous software in Korea. It is very useful to linguists In that it has various systems of foreign characters and enables us to edit enough new ones freely. It has already a broad system of the IPA, which cannot be used for narrow transcription. The writer proposes here a full system of the IPA revised to 1979, which you can get from the Phonetic Society of Korea or Hangul & Computer Co., Ltd., free of charge. To use the new system of the IPA in the Arae Hangul wordprocessor, you must replace six revised files: (1) SPECIAL2.SFT, (2) SPECIAL2.PFT, (3)SPECIAL2.PFT, (4)ASCII.SFT, (5)ASCII.PFT, (6)ASCII.LFT.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.04c
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• pp.91-97
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• 2008

Polymers submitted to thermo/electrical stress suffer from ageing that can drastically affect their functional behaviour. Understanding the physico/chemical processes at play during ageing and defining transport regimes in which these mechanisms start to be critical is therefore a prime goal to prevent degradation and to develop new formulation or new materials with improved properties. It is thought that a way to define these critical regimes is to investigate under which conditions (in terms of stress parameters) light is generated in the material by electroluminescence (EL). This can happen through impact excitation/ionization involving hot carriers or upon bi-polar charge recombination (a definition that excludes light from partial discharges, which would sign an advanced stage in the degradation process). After a brief review of the EL phenomenology under DC, we introduce a numerical model of charge transport postulating a recombination controlled electroluminescence. The model output is critically evaluated with special emphasize on the comparison between simulated and experimental light emission. Finally, we comment some open questions and perspectives.

• Journal of Sensor Science and Technology
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• v.31 no.4
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• pp.218-227
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• 2022

Triboelectric nanogenerators (TENGs), a new green energy, that have various potential applications, such as energy harvesters and self-powered sensors. The output performance of TENGs has been improving rapidly, and their output power significantly increased since they were first reported owing to improved triboelectrification materials and interfacial material engineering. Because the operation of a TENG is based on contact electrification in which electric charges are exchanged at the interface between two materials, its output can be increased by increasing the contact area and charge density. Material surface modification with microstructures or nanostructures has increased the output performance of TENGs significantly because not only does the sharp micro/nano morphology increases the contact area during friction, but it also increases the charge density. Chemical treatment in which ions or functional groups are added has also been used to improve the performance of TENGS by modifying the work functions, charge densities, and dielectric constants of the triboelectric materials. In addition, ultrahigh output power from TENGs without using new materials or treatments has been obtained in many studies in which special structures were designed to control the current release or to collect the charge current directly. In this review, we discuss physical and chemical treatments, bulk modifications, and interfacial engineering for enhancing TENG performance by improving contact electrification and electrostatic induction.

• Journal of Korea Port Economic Association
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• v.28 no.4
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• pp.275-298
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• 2012

Terminal operators have provided special services such as loading, discharging, stowage of cargo to the owner, and carriers of the sea, which contribute the domestic and international logistics. For smooth flow of logistics, container terminal should reserve spaces for inbound and outbound logistics. However, if it is unable to provide the spaces, which can be caused by labour strikes or terminal lockouts and so on, national logistic system and financial management of terminal operators can be seriously affected. In order to minimize these kinds of problems, terminal operators impose high rate of charges ("overstorage charge") to the accumulated cargoes and/or containers, which are stipulated in terminal service agreement. Nevertheless, if there is no terminal service agreement with an owner of cargo and/or container, any kind of charge can cause legal problems (conflict ??) between the cargo and terminal operator. In this regard, I would like to study on the definition of overstorage charge and the legal issue of it based on the Busan district court's judgment. In particular, I will propose a special right of commercial lien and public auction for terminal operators to settle accumulated cargoes in container terminal.

• Journal of Korean Society of Archives and Records Management
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• v.22 no.1
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• pp.133-157
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• 2022

Special subject archives in different fields have been established and the related studies have been constantly made so far, but no evaluation index reflecting the characteristics of the archives has yet been developed. Thus, this study intends to develop a draft of the special subject archive operation evaluation index through literature research and propose the special subject archive operation evaluation index through a Delphi survey. A Delphi survey was conducted thrice, with 10 persons in charge of archiving thematic archives in 5 fields. Finally, a special subject archive operation evaluation index consisting of 4 evaluation categories, 10 evaluation items, and 28 detailed items was proposed. This study is significant because it was the first in Korea to develop and propose an operation evaluation index for special subject archives.