• Title/Summary/Keyword: a brief review

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A Brief Review on 2-Dimensional Dielectric Nanosheets (이차원 유전체 나노시트의 개발 동향)

  • Yim, Haena;Choi, Ji-Won
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.35 no.1
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    • pp.1-10
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    • 2022
  • Two-dimensional materials have shown a great promise for the next-generation electronic materials due to their unique optical, physical, and chemical properties that are distinct from their bulk counterparts. Their atomic-level thickness, the feature for flexible tenability, and exposed huge surface allow various approaches for high-performance nanoscale devices. Especially, this review highlights the recent progress on two-dimensional dielectric nanosheets, which are obtained by cheap and massproducible solution-based exfoliation process, accompanied by the preparation methods, various deposition methods, and the characteristics of devices using a dielectric nanosheet thin films. We also present a perspective on the advantages offered by this two-dimensional dielectric nanosheets for the upcoming future nanoelectonics.

Temporomandibular joint re-ankylosis: a case report and literature review

  • Flora Kalita;Arunkumar KV
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.49 no.4
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    • pp.218-222
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    • 2023
  • Re-ankylosis is a common postoperative complication of temporomandibular joint (TMJ) ankylosis surgery. Various surgical options to prevent re-ankylosis, both with and without interpositional material, have been discussed in the literature. However, no standardized protocol has been suggested for management or prevention of TMJ ankylosis. This paper discusses the probable causes behind TMJ re-ankylosis and presents a case of unilateral TMJ re-ankylosis, which was managed by gap arthroplasty using an autologous abdominal dermal fat graft as an interpositional material and closely monitored for signs of relapse. Autologous fat graft acted as an effective barrier between the glenoid fossa and mandibular condyle, thus preventing dead space, hematoma and heterotrophic bone formation. A brief review of the literature and update on TMJ re-ankylosis are also presented.

Innate immune response to oral bacteria and the immune evasive characteristics of periodontal pathogens

  • Ji, Suk;Choi, Youngnim
    • Journal of Periodontal and Implant Science
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    • v.43 no.1
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    • pp.3-11
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    • 2013
  • Periodontitis is a chronic inflammation of periodontal tissue caused by subgingival plaque-associated bacteria. Periodontitis has long been understood to be the result of an excessive host response to plaque bacteria. In addition, periodontal pathogens have been regarded as the causative agents that induce a hyperinflammatory response from the host. In this brief review, host-microbe interaction of nonperiodontopathic versus periodontopathic bacteria with innate immune components encountered in the gingival sulcus will be described. In particular, we will describe the susceptibility of these microbes to antimicrobial peptides (AMPs) and phagocytosis by neutrophils, the induction of tissue-destructive mediators from neutrophils, the induction of AMPs and interleukin (IL)-8 from gingival epithelial cells, and the pattern recognition receptors that mediate the regulation of AMPs and IL-8 in gingival epithelial cells. This review indicates that true periodontal pathogens are poor activators/suppressors of a host immune response, and they evade host defense mechanisms.

UCP600: An Exercise in International Private Sector Self Regulation (UCP 600: 국제 사적 부문 자체 규제의 일례)

  • Byrne, James E.
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.36
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    • pp.47-84
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    • 2007
  • The Uniform Customs and Practice for Documentary Credits ("UCP") may be treated as a useful laboratory for studying the scope and limitations of self regulation. This is due to its almost universal success on a global stage which provides it a perspective rarely available for self regulatory provisions and due to extensive experience of judicial review of it. In this sense, it is worthwhile to examine in brief the latest iteration of the UCP, Publication No. 600 ("UCP600"). This article describes and analyze some of core provisions of the UCP600 from the perspective of their adequacy as an exercise in self regulation. It is attempted first in view of several categories of private rulemaking; definitional rulemaking, default rules, procedural rules, and remedies. After that, it is examined second in view of sound rulemaking which is related to the relative role of law and practice. It points out rich and varied insights into the possibilities and problems associated with private rulemaking in connection with commercial transactions.

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3D Printing Technologies - A Review (3D 프린팅 기술 동향)

  • Choi, Jae-Won;Kim, Ho-Chan
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.14 no.3
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    • pp.1-8
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    • 2015
  • Recently, a great interest in 3D printing has emerged, although many existing 3D printing technologies were first developed 2-3 decades ago. There are many mature 3D printing processes and materials; however, active research and development efforts are ongoing in this area to advance the technologies. Several companies have already started to use 3D printed parts as actual components. Many low-cost 3D printers have been released on the market, which are of particular interest to educators and hobbyists. This paper provides a brief review of 3D printing technologies and research trends. In addition, several state-of-the-art technologies and applications are introduced.

A Brief review of Aragonite Precipitated Calcium Carbonate (PCC) Synthesis Methods and Its Applications

  • Ramakrishna, Chilakala;Thenepalli, Thriveni;Ahn, Ji Whan
    • Korean Chemical Engineering Research
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    • v.55 no.4
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    • pp.443-455
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    • 2017
  • This article provides an exclusive overview of the synthesized aragonite precipitated calcium carbonate and its applications in various fields. The last decade has seen a steady increase in the number of publications describing the synthesis, characterization and applications of calcium carbonate morphologies. Mainly, two kinds of processes have been developed for the synthesis of aragonite precipitated calcium carbonate under controlled temperature, concentrations and aging, and the final product is single-phase needle-like aragonite precipitated calcium carbonate formed. This review is mainly focused on the history of developed methods for synthesizing aragonite PCC, crystal growth mechanisms and carbonation kinetics. Carbonation is an economic, simple and ecofriendly process. Aragonite PCC is a new kind of functional filler in the paper and plastic industries, nowadays; aragonite PCC synthesis is the most exciting and important industrial application due to numerous attractive properties. This paper describes the aragonite PCC synthetic approaches and discusses some properties and applications.

Primary Laryngeal Aspergillosis in Immunocompetent Patient - A Case Report and Review -

  • Kang, Sung-Mi;Hong, Hyun-Jun;Bae, Yoon-Sung;Yoon, Sun-Och
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.22 no.1
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    • pp.60-62
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    • 2011
  • Primary laryngeal aspergillosis is rare, It is most often found in immunocompromised patient, such as leukemia, malignant disease, diabetes or immunosuppressive drugs. These days the occurrences of laryngeal aspergillosis in immunocompetent patients are increasing. The cause of laryngeal aspergillosis in immunocompetent patients is not clear, but a few factors are considered such as iatrogenic factors, vocal abuse, vocal fold cyst and occupational factors. The histopathologic characteristics are somewhat different between that of immunocompromised patients and immunocompetent patients. We report a case of primary vocal cord aspergillosis in immunocompetent patient who had treated with only surgery and brief review of the pertinent literature.

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A review of fixed offshore platforms under earthquake forces

  • Hasan, Syed Danish;Islam, Nazrul;Moin, Khalid
    • Structural Engineering and Mechanics
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    • v.35 no.4
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    • pp.479-491
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    • 2010
  • Advances in geological studies, have identified increased seismic activity in the world's ocean once believed to be far from seismic hazards. The increase in demand of oil and other hydrocarbons leaves no option but to install a suitable offshore platform on these seismically sensitive offshore basins. Therefore, earthquake based design criteria for offshore structures are essential. The focus of the present review is on various computational techniques involved for seismic response study. The structural and load modeling approaches, the disturbed fluid-structure and soil-structure interaction as well as hydrodynamic damping due to earthquake excitation are also discussed. A brief description on the reliability-based seismic design approach is also presented.

Two-Phase Flows and Boiling Heat Transfer in Microchannels

  • Oh, Jong-Taek;Ardiyansyah, Ardiyansyah
    • International Journal of Air-Conditioning and Refrigeration
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    • v.16 no.2
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    • pp.51-63
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    • 2008
  • A study of literatures on flow boiling heat transfer and two-phase flows inside microchannels is summarized. The potential applications, fabrication method and efforts to determine certain dimensional threshold for microchannels classifications are discussed. For the last two decades, numerous two-phase flow and heat transfer models for microchannels have been developed; many of them were derived from empirical models originally applied for conventional channels. Those models are discussed here along with a brief review on recent development of theoretical and phenomenological-based models for microchannels. This study is devoted to provide a review of important issues on flow boiling heat transfer and two-phase flows inside microchannels, including two-phase flow patterns, boiling heat transfer mechanism and correlations developments, pressure drop and prediction methods, and critical heat flux.

A Brief Review on Variables and Test Priorities of Photovoltaic Module Life Expectancy

  • Padi, Siva Parvathi;Chowdhury, Sanchari;Zahid, Muhammad Aleem;Kim, Jaeun;Cho, Eun-Chel;Yi, Junsin
    • Current Photovoltaic Research
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    • v.9 no.2
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    • pp.36-44
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    • 2021
  • To endorse the reliability and durability of the solar photovoltaic (PV) device several tests were conducted before exposing to the outdoor field in a non-ideal condition. The PV module has high probability that intend to perform adequately for 30 years under operating conditions. To evaluate the long term performance of the PV module in diversified terrestrial conditions, one should use the outdoor performance data. However, no one wants to wait for 25 years to determine the module reliability. The accelerating stress tests performing in the laboratory by mimicking different field conditions are thus important to understand the performance of a PV module. In this review, we will discuss briefly about different accelerating stress types, levels and prioritization that are used to evaluate the PV module reliability and durability before using them in real field.