• The Journal of the Korean dental association
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• v.51 no.1
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• pp.39-45
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• 2013

Radiographic examinations are used to discover and define the type and extent of disease in many clinical situations. Currently, it is common for dental patients to receive dental radiographic examinations on a routine schedule with little variation in spite of different patient signs and symptoms. Such routine scheduling of radiographic examinations may result in unnecessary patient exposure. There is also the possibility of under-utilization of radiography; this can result in inadequate or excessively delayed diagnosis. Patient selection criteria are descriptions of clinical conditions derived from patient signs, symptoms and history that identify patients who are likely to benefit from a particular radiographic examination. It makes possible making individual decisions based on history, clinical examination and risk factors. The radiographic selection criteria of dentistry have been revised in accordance with recent guidelines and peer-reviewed research in USA and Europe, but the studies of these subjects are not sufficient in our nation. In this review article, the relating factors and update necessity of radiographic selection criteria are discussed.

• The Journal of the Korean dental association
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• v.55 no.3
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• pp.240-248
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• 2017

A keratinized gingiva is important to the natural teeth and it is more essential to the health of the peri-implant mucosa of the implants. There are various surgical methods to restore a keratinized gingiva. First, a clinician could utilize apically positioned flap operation. This flap operation technique could be used as a full or partial thickness. If there is little keratinized gingival tissue available for the apically positioned flap operation, free gingival grafting should be used. Its technique sensitivity is relatively high, but using various surgical techniques and disciplines makes it simple and have the good predictability. There have been many considerations for those surgical techniques. Clinicians who treat for periodontitis or operate implant surgeries have to know the considerations and surgical methods.

• Journal of the Korean Professional Engineers Association
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• v.33 no.2
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• pp.18-21
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• 2000

As consumer, one of the most important things how to get manufactured good is an assurance of quality. We have a consumer protection law which is weaker than product liability law(so called PL law), but stronger than civil law. In this special issue, we want to explain PL law which will be legislated within not long time and to propose a method of protection and defence in building and housing field. As the quality control of constructor, ISO 9000 series for quality assurance and CM (Construction Management) for quality assister are concerned in all construction process. Therefore, above mentioned PL law is very serious problems which are applied in apartment housing, if applied, a little part as not real estate will be possible.

• The Journal of the Korean dental association
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• v.15 no.2
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• pp.107-110
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• 1977

Class I malocclusion is essentially a dental dysplasia. Rotations, individual tooth malpositions, missing teeth, tooth size discrepancies, etc., fall under this classification. There are two types of class I malocclusions. One is identified by and insufficient denture base to accommodate the teeth; the other has more denture base than tooth material, creating spaces in the arch. The tooth material-to denture base discrepancies may be slight, calling for only a little increase in arch length for alignment and the correction of minor rotations. Discrepancies may also be great, in which case it becomes necessary to reduce tooth material by extraction, so as to make the tooth material more in proportion to the size of the denture base. The author had attempted orthodontic treatment of a class I malocclusion case of 13-year old boy in which high canines and impacted mandibular second premolars were involved. The author obtained good results.

• 한국기계연구소 소보
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• s.20
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• pp.71-78
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• 1990

This investigation was undertaken to establish the technologies of grain refinement and modification, and to characterize material properties, essential for high quality aluminum alloy castings. Grain refinement seldom changed DAS and eutectic Si size, but largely decrease grain size. The variations of grain size induced by grain refinement had a great influence on the elongation without changes in the tensile strength or yield strength. The optimum Ti level lies between 0.1% and 0.16% to achieve the best possible mechanical properties. DAS and grain size were little affected, but eutectic Si size was greatly refined by modification. The variation of eutectic Si size had a great effect on the elongation, impact value, fracture toughness and fatigue crack propagation rate without changes in the tensile strength or yield strength. The Sr content of 0.015% is optimum to modification.

• Journal of the Korean Professional Engineers Association
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• v.44 no.5
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• pp.31-35
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• 2011

The WHO/International Agency for Research on Cancer(IARC) has classified radiofrequency electromagnetic fields as possibly carcinogenic to humans(Group 2B), based on an increased risk for glioma, a malignant type of brain cancer, associated with wireless phone use on 31, May 2011. It takes 10 years after announcing the electric magnetic as possibly carcinogenic to humans(Group 2B) and 14 years after starting research project. It is too late as mentioned, too weak in terms of the same class to 'pickles & coffee' and too little in terms of using words 'more studies required'. The guidelines on human exposure to electromagnetic fields have been developed to provide guidance to identify the safety of exposure to electromagnetic fields. On the recent recommendations of safety guidelines, there has been discussion on possible chronic effects of electromagnetic fields with much lower or no threshold. This paper riviews the global trends of safety guidelines and has suggested the new guidelines for protecting the human health, wildlife and insects.

• Electronics and Telecommunications Trends
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• v.37 no.4
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• pp.1-10
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• 2022

As the response to climate change becomes a more pressing global issue, so do expectations for climate change in the green information and communication technology (ICT) industry and the possibility of solving environmental problems through ICT. However, because the green ICT industry is still in its early stages, there is little research on it. Understanding the startup ecosystem in the industry is helpful for recognizing innovation trends in emerging technologies such as green ICT. In this regard, this paper investigates the current state and characteristics of the green ICT ecosystem and presents implications based on an examination of startup venture capital investment trends and submarket identification in the green ICT industry as emphasized by the carbon neutrality paradigm shift. The analysis included 4,807 companies and 3,990 funding records, as well as exploratory data analysis and "k-means" clustering techniques.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.4 no.2
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• pp.119-128
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• 1975

Natural draft and flow which low temperature moist gas produces in the chimney of an Ondol heating system were numerically analysed. Among several factors involved inlet gas temperature has the strongest influence on the chimney performance and then next specific humidity of the gas. Thermal conductivity of the chimney wall, however, has little influence on the performance of such a low temperature chimney. Under given flow conditions there exists an optimum chimney height which gives a maximum flow rate for a given chimney diameter. This optimum value of chimney height inereases with increase in chimney diameter, inlet gas temperature and specific humidity.

• Fashion & Textile Research Journal
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• v.16 no.3
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• pp.366-377
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• 2014

This paper is a comparative research study between Korean and American women's garments from the 1910s to 1930s. It focuses on the articles and advertisements of Korean women's magazines and American women's magazines. The Korean women's magazines investigated are 신여자[Siyeoja], 신가정[Singajung], 부인[Buin], 신여성[Sinyeosung], and 여성[Yeosung]. The American woman's magazine investigated is Ladies' Home Journal. This paper explores the differences and similarities between the garments that appear in these magazines. There is little evidence about women's clothing in Korean women's magazines while the American women's magazine includes a lot of information about women's dress and life. Korean women usually wore Korean traditional costumes with traditional terms like Chima and Jeogori but they wore western shoes, stockings, shawls, umbrellas, and some clothing with western materials such as lace, velvet, and rayon with borrowed words. These western accessories and some clothing materials like lace and rayon were the same fashion in America. So, Korean women wore traditional and western clothing together while American women wore clothing influenced by Paris fashion. American women wore various pieces of clothing like suits, frocks, coats and sportswear with undergarments. There were also lots of advertisements about women's under garments and sportswear which was different from Korean women's clothing during the period.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.7
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• pp.1082-1094
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• 2008

The present study analyzed the differences of advertisement design, expression method, and appeal types in the men's fashion product advertisement from men's magazines between 1996 and 2006, according to the year, season, and the type of the magazine. The magazines chosen for the analysis were Korean Esquire, GQ, and Shin-dong-a. 2058 advertisement out of 88 sample magazines were chosen and analyzed by frequency, and chi-square using SPSS statistic package. The results of the study were as follows. First of all, there were more advertisements without copy, and even when the copy was used, it was used as a headline only. Secondly the poster style layout was used more frequently than other layouts, and one male model wearing the product was the most popular. Thirdly the types of appeal in advertisement, sensuous appeal was most frequently used. The results of the study showed that there is little advertisement differentiation in men's fashion product advertisement. Therefore in order to draw consumer's attention. various and unique advertisement design should be implemented.