• Imaging Science in Dentistry
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• 제54권1호
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• pp.1-11
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• 2024

Purpose: This study was conducted to investigate the safety of dental imaging in pregnant women with respect to fetal health. Materials and Methods: Searches were conducted of the PubMed, Scopus, and Web of Science databases in May 2023. The inclusion criteria encompassed cross-sectional and longitudinal studies that focused on the analysis of diagnostic dental imaging in pregnant women, as well as studies utilizing phantoms to simulate imaging examinations. The exclusion criteria consisted of reviews, letters to the editor, book chapters, and abstracts from scientific conferences and seminars. Results: A total of 3,913 articles were identified. Based on a review of the titles and abstracts, 3,892 articles were excluded, leaving 21 articles remaining for full-text review. Of these, 18 were excluded, and 4 additional articles were included as cross-references. Ultimately, 7 articles underwent quantitative-qualitative analysis. Three retrospective studies were focused on pregnant women who underwent dental imaging procedures. The remaining 4 studies utilized female phantoms to simulate imaging examinations and represent the radiation doses absorbed by the uterus or thyroid. Conclusion: Few dental radiology studies have been conducted to determine the safe radiation threshold for pregnant women. Additionally, the reviewed articles did not provide numbers of dental examinations, by type, corresponding to this dose. Dental imaging examinations of pregnant women should not be restricted if clinically indicated. Ultimately, practitioners must be able to justify the examination and should adhere to the "as low as diagnostically acceptable, being indication-oriented and patient-specific" (ALADAIP) principle of radioprotection.

• 대한기계학회논문집A
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• 제26권2호
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• pp.234-242
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• 2002

A shape optimal design of synthetic intervertebral disc prosthesis is performed using a three-dimensional finite element method. Geometric parameters are introduced to model the cross-sectional geometry of the intervertebral disc. It is assumed that the total strain energy in the intact intervertebral disc is minimized under the normal load conditions, as often cited in other references. To calculate the stain energy density, both the nonlinear material properties and the large deformations are taken into account. The design variables of the annulus fiber angle and the area ratio of the nucleus pulposus are calculated as 31°and 30%, respectively, which complies well with the intact disc. Thus, the same optimization procedure is applied to the design of the synthetic intervertebral disc prosthesis whose material properties are different from the intact disc. For the given synthetic material properties, the values of 67°and 24% for the fiber angle and the area ratio are obtained.

• Journal of the Korean Wood Science and Technology
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• 제45권6호
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• pp.828-835
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• 2017

Airtightness of buildings is one of critical aspects of its energy performance. To build up references of airtightness of wooden houses built in Korea, blower door tests have been carried out in 42 houses since 2006. Causes of air leakage were investigated recently. The average value of air change rate was $3.7h^{-1}$ for light frame house and $5.5h^{-1}$ for post-beam construction at ACH50 (air change per hour at 50 Pa air pressure difference). Foam type insulation was more advantageous in ensuring building airtightness than glass fiber batt. Airtightness of wooden houses which were constructed after 2010 was improved to have less than $1.5h^{-1}$ of ACH50, threshold for application of artificial air change. The average air change rate of CLT (cross laminated timber) houses showed the lowest value, $1.1h^{-1}$, among the tested structures.

• 한국의사학회지
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• 제31권1호
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• pp.135-147
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• 2018

Analyzing the Book of Changes, researchers noted that animals and plants utilized as symbols in the Book of Changes were later used as medicinals in East Asian medicine. They found 24 animals and plants utilized as symbols in the Book of Changes; specifically in six statements on the hexagrams and 53 statements on the lines. The animal and plant symbols in 59 statements are more clearly interpreted with the descriptions in the Compendium of Materia Medica. Eleven plants referenced in the Book of Changes were written with their nicknames, causing confusion to the researchers of later times. Using the Compendium of Materia Medica however, these plants can be identified. Livestock were mentioned 34 times among the 59 statements, with horse and cattle being the most often at eight times, each. They are subdivided according to their sex and color. The writers of the Book of Changes constructed an elaborate symbol system with the animals that are familiar to people, and which, through this research, has been decoded through cross references to the Compendium of Material Medica.

• 한국언어정보학회지:언어와정보
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• 제19권1호
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• pp.37-57
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• 2015

This paper is primarily intended to provide a new insight on which the structural properties of As-Parenthetical constructions shown by Potts (2002) might be regarded as cross-linguistically common one. As a first attempt, it introduces the characteristics of Korean As-Parenthetical by carefully investigating them through the data, focusing on the similarities or differences between two languages with a constructional theoretical perspective. The paper here provides three properties of Korean as-clauses in the morphological and syntactic aspects. First, the morpheme 'as' in English as-clause would be realized as three different morphemes as a bound one. Korean as-clauses can be introduced by three different morphemes, '-tusi, -chelem, -taylo' and unlike that in English as-clauses, they behave as bound morphemes which do not stand alone. Even though they are attached into different morpho-syntactic stems, they do not make any meaning change only under this clause. Secondly, two syntactic types of as-clauses can also be found in Korean, similarly to those of English: CP-As type and Predicate-As type, depending on which types of gap they involve in. English has one more subtype of Predicate-As type (called inverted Predicate-As clause), while Korean does not show this subtype. Thirdly, the various mismatches attributed by the gap and the antecedent come from the constructional restrictions of as-clauses in Korean. In addition, the paper attempts to display various ambiguities from the as-clauses through disjoint references or negative sentences in As-Parenthetical constructions.

• 대한금속재료학회지
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• 제46권11호
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• pp.755-761
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• 2008

We fabricated thermally evaporated 10 nm-Ni/1 nm-Ir/(poly)Si films to investigate the energy saving property of silicides formed by rapid thermal annealing (RTA) at the temperature range of $300{\sim}1200^{\circ}C$ for 40 seconds. Moreover, we fabricated 100 nm-thick ITO/(poly)Si films with an rf-sputter as references. A transmission electron microscope (TEM) and an X-ray diffractometer were used to determine cross-sectional microstructure and phase changes. A UV-VIS-NIR and FT-IR (Fourier transform infrared spectroscopy) were employed for near-IR and middle-IR absorbance. Through TEM analysis, we confirmed 20~65 nm-thick silicide layers formed on the single and polycrystalline silicon substrates. Ir-inserted nickel silicide on single crystalline substrate showed almost the same absorbance in near IR region as well as ITO, but Ir-inserted nickel silicide on polycrystalline substrate, which had the uniform absorbance in specific region, showed better absorbance in near IR region than ITO. The Ir-inserted nickel silicide on polycrystalline substrate particularly showed better absorbance in middle IR region than ITO. The results imply that nano-thick Ir-inserted nickel silicides may have excellent absorbing capacity in near-IR and middle-IR region.

• International Journal of Computer Science & Network Security
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• 제21권1호
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• pp.77-83
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• 2021

The dependency on technology has increased with the increase in population. Technology plays a crucial role in facilitating, organizing and securing people's life nowadays. The Internet has penetrated every face of present-day lifestyles. Yet another ubiquitous use of digital technology today is evident in transferring money and speeding cross border payments that are done through digital transactions. This paper investigates transferring money and data through banks and companies by using the Blockchain concept through decentralized distributed system. The present research also peruses several contexts in which this technology has already been implemented successfully and demonstrates the advantages of replacing the paper money with digital money. Using cryptocurrency will facilitate people's life by reducing time, securing the process of money transfer, and increasing data integrity. The primary benefit of this content analysis is that it addresses an innovative subject, in a new light and using timely recent research references drawn from 2018-2020. Thus, our study is a contemporary and conclusive source for all present and future endeavours being undertaken in the domain of using blockchain for e-transactions.

• 한국항공운항학회지
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• 제30권3호
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• pp.117-122
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• 2022

A method to increase the effectiveness of flight training at a low cost by applying the correct flight training method to students without flight experience is a very important factor. BATD equipped with an extended display device enables the proper cross-check of external references and internal instruments by integrated flight instruction methods, enabling effective flight training in the initial stages. In addition, BATD employs the Cessna 172 model with Glass Cockpit to help make it easy to apply to actual flights. As a result of analyzing the effect of flight training through a survey of students who completed the BATD practice lecture, it was very helpful to understand the theories related to flight that they had already learned, and they responded that they could easily adapt to all flight subjects in additional FTD practice lectures. Therefore, a well-planned BATD practice lecture will be easy to adapt to real flight training, which will have significant effects in reducing time and cost.

• 대한한의학원전학회지
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• 제35권3호
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• pp.71-90
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• 2022

Objectives : This paper summarizes contents on fish in the Injeji and Jeoneo-Ji parts in the Imwon-Gyeongje-Ji and compares them with those in the Dong-uibogam from a Korean Medical perspective. Methods : Most of the knowledge of fish in the Imwon-Gyeongje-Ji is based on preceding material medica studies such as the Dongui-bogam in Joseon, the Bencao-gangmu in China, and the Hwahan Samjaedohoe in Japan. The influential relationships and the process of change among these knowledge information were examined within the context of each literature's development or through identifiable changes in knowledge on each particular kind of fish. Results & Conclusions : In the Imwon-Gyeongje-Ji, the consisting 16 parts are organically connected, sometimes functioning as cross-references. In particular, the medical contents on the efficacy of fish for treating disease is closely linked to contents on fish ecology and environment as written in the Jeoneo-Ji, which deals with the field of living things. On the more detailed knowledge on about 30 kinds of fish, one could grasp the formation process and changes of East Asian traditional knowledge on fishkind among historical study of influential Chinese texts, new stimulation and methodology through Japanese literature on natural history, and dynamic processes of inheriting and selectively accepting traditional knowledge of Joseon.

• 정보기술과데이타베이스저널
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• 제1권1호
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• pp.31-62
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• 1994

Information systems for application areas like office automation, customer service or computer aided manufacturing are usually highly interactive and deal with complex document structures composed of multiple media formats. For the realization of these systems, nonstandard database systems, which we call document databases, need to handle different types of coarse-and fine-grained document objects(like full-text documents, graphics and images), hierarchical and non-hierarchical relationships between objects(like composition-links and cross-references using hypertext structures) and document attributes of different types such as formatting/presentation information and access control. In this paper, we present the underlying data model for document databases based on descriptive markup languages that provide mechanisms for specifying the logical structure(or schema) of individual documents stored in the database. We then describe extensions to the data model for supporting notion of composite structures("join" operators for documents) --composition and hyperlinking mechanisms for representing compound documents and inter-linked documents as unique entites separate from their components. Furthermore, due to the interactive nature of the application domains, the database system in conjunction with clients(or browsers) has to support visual navigation and graphical query mechanisms. We describe the functionality of a new user interface paradigm called HyBrow for meeting the above mentioned requirements. The underlying implementation strategy is also discussed.discussed.