• Korean Chemical Engineering Research
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• v.51 no.2
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• pp.214-220
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• 2013

Hydrophobic coating on a silicate-based yellow phosphor ($Sr_2SiO_4:Eu^{2+}$) was carried out by using hexamethyldisiloxane (HMDSO) precursor in an atmospheric pressure dielectric barrier discharge plasma reactor, eventually to improve the long-term stability and reliability of the phosphor. The phosphor powder samples were characterized by a scanning electron microscope (SEM), a transmission electron microscope (TEM), a fluorescence spectrophotometer and a contact angle analyzer. After the coating was prepared, the contact angle of the phosphor powder increased to $133.0^{\circ}$ for water and to $140.5^{\circ}$ for glycerol, indicating that a hydrophobic layer was formed on its surface. The phosphor coated with HMDSO exhibited photoluminescence enhancement up to 7.8%. The SEM and TEM images of the phosphor powder revealed that the plasma coating led to a morphological change from grain-like structure to smooth surface with 31~46 nm thick hydrophobic layer. The light emitting diode (3528 1 chip LED) fabricated with the coated phosphor showed a substantial enhancement in the reliability under a special test condition at $85^{\circ}C$ and 85% relative humidity for 1,000 h (85/85 testing). The plasma-mediated method proposed in this work may be applicable to the formation of 3-dimensional coating layer on irregular-shaped phosphor powder, thereby improving the reliability.

• Spatial Information Research
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• v.23 no.6
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• pp.9-17
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• 2015

The convergence industry is a combination of technologies or industries of the same type or various types, thereby maintaining and/or expanding the existing values or creating fresh values. As the industry is drawing greater attention over the world, each country is making huge efforts to provide support for it. GeoSpatial Information is a representative convergence industry characterized by being utilized as a basis for other industrial fields by being linked and fused with other industries and technologies. It is well recognized as being a promising industry that will likely lead the national economy in the future. GeoSpatial Information is necessary to analyze the distinctive features and obstacle factors of the convergence industry. Because it will be able to induce a smooth convergence among different industries. In this paper, we has segmented the support elements through a comparative analysis of the legal system related to (Nano Technology, Information and Communication Technology, Culture Technology, etc)the convergence industry. Based on this proposed policy support for GeoSpatial Information Convergence industry. We expect that this study will be used as basic data of the policy established to effectively support for the GeoSpatial Information convergence industry.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.1
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• pp.71-78
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• 2020

In the case of power generation using renewable energy, power production may not be smooth due to the influence of the weather. The energy storage system (ESS) is used to increase the efficiency of solar and wind power generation. ESS has been continuously fired due to a lack of battery protection systems, operation management, and control system, or careless installation, leading to very big casualties and economic losses. ESS stability and battery protection system operation management technology is indispensable. In this paper, we present a battery level calculation algorithm and a failure prediction algorithm for ESS optimization and stable operation. The proposed algorithm calculates the correct battery level by accumulating the current amount in real-time when the battery is charged and discharged, and calculates the battery failure by using the voltage imbalance between battery cells. The proposed algorithms can predict the exact battery level and failure required to operate the ESS optimally. Therefore, accurate status information on ESS battery can be measured and reliably monitored to prevent large accidents.

• The Journal of the Korea Contents Association
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• v.20 no.11
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• pp.145-156
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• 2020

Recently, as a culture that values work-life balance has become more important in society as a whole, interest in hobbies and leisure activities that will enrich life is increasing. This phenomenon is due to an increase in platforms where people can enjoy and learn hobbies online. Among them, craft-related content is growing rapidly, and as offline education has been brought online, learning immersion has been reduced online. Therefore, in this study, we want to identify current problems in online and offline craft learning and seek ways to improve UI design to solve them. To this end, we conducted a literature survey on the online learning platform, online craft learning platform and UI design, and based on this, conducted case investigation and analysis to derive the third stage of the learning process of the online craft learning platform. Subsequent surveys showed that as a result, the online craft learning platform was able to find improvements in terms of differentiating the content exploration process, visualizing the craft progress stage, ease of working with video tools, and providing smooth feedback, and in addition to the need for a device for active learning. Through the results of this study, we hope to expand the craft content market by making it easier for users to enjoy the contents provided on the online craft learning platform.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.22 no.4
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• pp.442-448
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• 2000

Developmental anomalies arising from the branchial apparatus include cysts, external sinuses, internal sinuses, and complete fistulas. Second branchial cleft cysts are by far the most common among these anomalies. It may occur at any age, being most common in the third decade, and more frequent in the male than in the female. It usually presents a smooth, round, nontender fluctuant mass located between the level of the tragus and the clavicle along the anteromedial border of the sternocleidomastoid muscle. It is lined by respiratory or squamous epithelium unless inflammation is present. The considerable amount of lymphoid tissue may be found beneath the epithelium. The treatment of choice of branchial cleft cyst is surgical excision. If the lesion is acutely infected, however, it is essential to relieve the infection prior to the surgery. This report deals with two cases of second branchial cleft cyst. In case 1, the cyst had rapidly increased in size over pregnant period. In case 2, the patient presented the swelling in the left neck, and had the history of incision and drainage because of misdiagnosis as submandibular space abscess. The infection was treated by antibiotic therapy in the first place, and then complete surgical excision was made. There was no evidence of any recurrence or complications for these $3{\sim}4$ years.

• Journal of Korean Academy of Nursing Administration
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• v.8 no.1
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• pp.73-83
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• 2002

To identify the effects of preceptorship on teaching effectiveness at clinical nursing education, a group of nursing students who participate in program under the instruction of the preceptors was compared with the other group of nursing students trained by head nurses.The data were collected from 14 Mary. 2001 to 8 June 2001. The subjects of this study were 85 nursing students trained by the preceptors in the G. medical college hospital in Inchon, and 122 nursing students trained by head nurses at several hospitals in Inchon and Puchon, Korea. The scale for measuring the teaching effectiveness and satisfaction of student for clinical practice developed by Kim, Miae and Lee, Sookja were employed as the tool for the study. The data collected were analysed with SPSS on the teaching effectiveness items, then mean value and SD were evaluated. The t-test were also employed to compare the teaching effectiveness and satisfaction of student for clinical practice of the both groups. The relation of teaching effectives and satisfaction of student for clinical practice were analysed with Pearson's correlation coefficient. The following findings were carried out from this study. 1) The group trained by preceptors showed significant higher teaching effectiveness statistically than the group trained by head nurses, scored mean value of 3.46 and 3.04 respectively in the item of teaching effectiveness. 2) The respective item showing high score of teaching effectiveness in both groups was 'smooth and reasonable dealing on the issues occurred in the wards'. But the items of 'help nursing students to familiarize with other staffs quickly'and 'help always at near' showed low scores. 3) For 5 causal factors classified on the teaching effectiveness, the factor of 'professional knowledge and capability' got the highest score, but 'availability as a supporter' showed the lowest score in both groups. 4) The group trained by preceptors showed significant higher students' satisfaction of clinical practice than the group trained by head nurses, scored mean value of 3.54 and 3.17. 5) Total teaching effectives were posive correlation with students' satisfaction of clinical practice significantly (r=0.603)

• Journal of Digital Convergence
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• v.16 no.9
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• pp.11-20
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• 2018

The Q&A board is widely used as a means of communicating service enquiries, and the need for efficient management of the enquiry system has risen because certain questions are being repeatedly and frequently registered. This study aims to construct a student-centered FAQ, centered on the unstructured data posted on the university homepage's Q&A board. We extracted major keywords from 690 postings registered in the recent 3 years, and conducted the semantic network analysis to find the relationship between the keywords and the centrality analysis in order to carry out network visualization. The most central keywords found through the analysis, in order of centrality, were application, curriculum, credit point, completion, graduation, approval, period, major, portal, department. Also, the major keywords were classified into 8 groups of course, register, student life, scholarship, library, dormitory, IT and commute. If the most frequent questions are organized into these areas to form the FAQ, based on the results above, it is expected to contribute to user convenience and the efficiency of administration by simplifying the service enquiry process for repeated questions, as well as enabling smooth two-way communication among the members of the university.

• Journal of the Microelectronics and Packaging Society
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• v.24 no.4
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• pp.65-71
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• 2017

To prepare the Cu-based filler material indicating enhanced oxidation resistance property and Ag content, Ag-coated Cu particles was fabricated by Ag plating of 40 wt % on the spherical Cu particles with an average size of $2{\mu}m$ and their oxidation behavior was also evaluated. In the case that ethylenediaminetetraacetic acid was used alone, the fabricated particles frequently showed broken structures such as delamination at Ag shell/core Cu interface and hollow structure that are induced by excessive galvanic displacement reaction. As a result, fraction of defect particles increased up to 19.88% after the Ag plating of 40 wt.%. However, the fraction in the 40 wt.% Ag-coated Cu particles decreased to 9.01% and relatively smooth surface and dense microstructure in the Ag shell were also observed with additional usage of hydroquinone as a complexing agent. Ag-coated Cu particles having the enhanced microstructure did not show any weight increase by oxidation for exposure to air at $160^{\circ}C$ for 2 h, indicating increased oxidation resistance property.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.6
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• pp.54-67
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• 2013

The main purpose of this study is to analyze the diversion rate by the levels of delay and the types of display. For this study, we developed the logit model by analyzing the result of SP survey of drivers who have driver's licence after manipulating a virtual driving simulator. The result of analysis was that the types of display was not statistically significant to the diversion rate. On the other hand, the levels of delay was very meaningful factor with the diversion rate. When the main road was flowing smoothly, drivers started to detour at the levels of delay 125% under the traffic free flow state. Similarly, when the levels of delay got worse, the diversion rate kept the same percentage as it was at the levels of delay 125% state which represented a smooth road condition. Likewise, when the main road's traffic flow was slow, drivers appeared to make detours at the same state of the levels of delay 125%. It was found that as the levels of delay got worse, the diversion rose higher than the diversion rate at the condition of slow traffic flow situation with the levels of delay 125%. The result of this study suggests the criterion of drivers detour point. For the conclusion, the result of study would be a reasonable reference for establishing transportation strategies by reflecting drivers' detouring property and would improve the efficiency of traffic flow.

• Journal of Korean society of Dental Hygiene
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• v.2 no.1
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• pp.97-113
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• 2002

This research is an attempt to establish a basic material in discovering the subjective types of the dental coordinators occupational consciousness, utilizing the Q-Method Theory, which is capable of measuring the subjective nature of human being by scientific and systematic method. The characteristics of each type were analyzed so as to have the dental coordinator to possess the desirable understanding of the occupational view together for them to have self-confidence as a lifetime specialty occupation. Upon completion of the study, it was found that there are three types of subjective views pertaining to the occupational consciousness on the dental coordinator. The result on the analysis of the characteristics is as follows : Type 1 is the Taking Serious View on the Patient Service, which priority is placed on kindness and looking after any difficulties of the patient, namely, it is the type that puts the importance on the high level medical examination and treatment based on good service. Because of the kind service to the patient, those under this category considered their job satisfaction have been improved. It goes without saying that they were developing the services, which satisfy themselves, and it was confirmed that they thought that they should make things smooth for any development of problems that may arise between the patient and the dentist. Type 2 is the Taking Serious View on Career and Organizational Strength. This is a type that aims on the systematic nature of the internal job, namely, organizational strength itself viewed from the stand point thai either self-confident or work merit is proportional to experience. This type is to actively treat the problem and endeavor to solve the issue when dissatisfaction is held by the dental hospital system, which is either followed according to the work responsibility or by an organization having an appropriate system on remuneration, Type 3 is the Placing of Importance on the Overall Circumstances. This is the type that places importance on the overall now of the dental hospital, and it is the type, that most greatly recognizes the importance of the role of the dental coordinator. The dental coordinator should provide the sense of reliability to both the dentist and to the staff of the medical examination and treatment and should be able to adjust smoothly the overall now of the medical treatment. The dental coordinator is expected to be a medical service specialist, who is capable to solve the problems of the staff of the medical treatment intuitively and to adjust the relation between the employees. With the above result, it was found that although there was no mutual exclusiveness between the respective types, there are particular characteristics among each type. Therefore, this research has discovered and analyzed the subjective view types relative to the occupational consciousness of the dental coordinator for the proper understanding on the characteristics of each type to enable the dental sanitary students and the graduates of the Dental Sanitary Department, who are aspiring to become dental coordinator, as the basic guide material to be actively utilized.