• 제목/요약/키워드: Promising Fields

검색결과 274건 처리시간 0.031초

Properties of Indium Tin Oxide Multilayer Fabricated by Glancing Angle Deposition Method

  • Oh, Gyujin;Lee, Kyoung Su;Kim, Eun Kyu
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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    • pp.367-367
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    • 2013
  • Commercial applications of indium tin oxide (ITO) can be separated into two useful areas. As it is perceived to bear electrical properties and optical transparency at once, its chance to apply to promising fields, usually for an optical device, gets greater in the passing time. ITO is one of the transparent conducting oxides (TCO), and required to carry the relative resistance less than $10^{-3}{\Omega}$/cm and transmittances over 80 % in the visible wavelength of light. Because ITO has considerable refractive index, there exist applications for anti-reflection coatings. Anti-reflection properties require gradual change in refractive index from films to air. Such changes are obtained from film density or nano-clustered fractional void. Glancing angle deposition (GLAD) method is a well known process for adjusting nanostructure of the films. From its shadowing effects, GLAD helps to deposit well-controlled porous films effectively. In this study, we are comparing the reference sample to samples coated with controlled ITO multilayer accumulated by an e-beam evaporation system. At first, the single ITO layer samples are prepared to decide refractive index with ellipsometry. Afterwards, ITO multilayer samples are fabricated and fitted by multilayer ellipsometric model based on single layer data. The structural properties were measured by using atomic force microscopy (AFM), and by scanning X-ray diffraction (XRD) measurements. The ellipsometry was used to determine refractive indices and extinction coefficient. The optical transmittance of the film was investigated by using an ultraviolet-visible (UV-Vis) spectrophotometer.

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수면다원검사의 정도관리 - 한국에서의 경험 및 제언 (Quality Assurance in Polysomnography - A Korean experience and critical suggestions)

  • 정도언
    • 한국의료질향상학회지
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    • 제1권1호
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    • pp.124-131
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    • 1994
  • Polysomnography is an essential methodology for diagnosing and following up sleep disorders and doing researches on human sleep. Sleep medicine, mainly with the utilization of polysomnographic techniques, has developed itself as one of the promising fields in the 21st century medicine. Korea is not an exception in importing and developing sleep medicine into the conventional medicine. However, it still remains to be clarified what polysomnography is for and how it should be done, considering the relatively recent introduction of sleep medicine into Korea. The author, being a board-certified sleep medicine specailist, having experienced spreading out sleep medicine within Korea for the past four years, and having recently set up a major sleep study facility in Korea at Seoul National University Hospital, attempts in this introductory critical article to review the essential issues related to quality assurance in polysomnographic study of human sleep. Also, unconditional introduction of "automated" sleep scoring system, which has been found to have significantly reduced reliability in various studies including the author's own, is critically reviewed. The author suggests that quality assurance and training program should be initiated and established by a responsible sleep medicine-related organization such as the Korean Association of Sleep Medicine and Psychophysiology.

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Use of Water Buffalo for Environmental Conservation of Waterland - Review -

  • Georgoudis, A.G.;Papanastasis, V.P.;Boyazoglu, J.G.
    • Asian-Australasian Journal of Animal Sciences
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    • 제12권8호
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    • pp.1324-1331
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    • 1999
  • The aim of this paper is to propose the preservation of buffaloes not only as productive livestock, but also as a part of the biodiversity of wetlands and especially of the Greek wetlands. The water buffalo used to be an integral part of the biodiversity of many Greek wetland ecosystems, enriched their landscape, and provided invaluable services and products to the rural people and to the economy in general. Its total population before the 1950s was over 100,000 animals. Presently, it is found only in four wetland sites in Macedonia and Thrace and in the estuaries of Rivers Gallikos and Axios, with a total population of a few hundred animals. These wetlands are Ramsar Sites. Even this small population is threatened with immediate extinction because of the rapidly changing rural socio-economic conditions and the expansion of cultivated fields into wet meadows. Farmers and consumers are rapidly losing contact with this mammal and its products. This species possesses minimum requirements for treatment and is characterized by the ability of utilizing roughage of variable nutritional value. These factors are promising to render buffalo breeding a valuable branch of the Greek livestock sector, which can also contribute to the maintenance of the wetlands.

Improving Protein Production on the Level of Regulation of both Expression and Secretion Pathways in Bacillus subtilis

  • Song, Yafeng;Nikoloff, Jonas M.;Zhan, Dawei
    • Journal of Microbiology and Biotechnology
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    • 제25권7호
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    • pp.963-977
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    • 2015
  • The well-characterized gram-positive bacterium Bacillus subtilis is an outstanding industrial candidate for protein expression owing to its single membrane and high capacity of secretion, simplifying the downstream processing of secretory proteins. During the last few years, there has been continuous progress in the illustration of secretion mechanisms and application of this robust host in various fields of life science, such as enzyme production, feed additives, and food and pharmaceutical industries. Here, we review the developments of Bacillus subtilis as a highly promising expression system illuminating strong chemical- and temperatureinducible and other types of promoters, strategies for ribosome-binding-site utilization, and the novel approach of signal peptide selection. Furthermore, we outline the main steps of the Sec pathway and the relevant elements as well as their interactions. In addition, we introduce the latest discoveries of Tat-related complex structures and functions and the countless applications of this full-folded protein secretion pathway. This review also lists some of the current understandings of ATP-binding cassette transporters. According to the extensive knowledge on the genetic modification strategies and molecular biology of Bacillus subtilis, we propose some suggestions and strategies for improving the yield of intended productions. We expect this to promote striking future developments in the optimization and application of this bacterium.

Genetic Diversity and Molecular Phylogeny of Cyanobacteria from Sri Lanka Based on 16S rRNA Gene

  • Wanigatunge, R.P.;Magana-Arachchi, D.N.;Chandrasekharan, N.V.;Kulasooriya, S.A.
    • Environmental Engineering Research
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    • 제19권4호
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    • pp.317-329
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    • 2014
  • The diversity of cyanobacteria in Sri Lanka was studied in different water reservoirs, paddy fields, brackish water and tsunami affected areas using light microcopy, 16S rRNA sequences, followed by phylogenetic analysis. Based on light microscopy, 24 genera were identified from environmental samples belonging to the orders Chroococcales, Oscillatoriales, Pleurocapsales and Nostocales. In cultures, 33 genera were identified from all five cyanobacterial orders, including Stigonematales. Based on 16S rRNA gene sequences and their morphology, two isolates were identified up to species level, 72 to genus level, one isolate up to family and 11 up to order level. Twelve isolates couldn't be assigned to any taxonomic level. The results of 16S rRNA gene sequences along with the phylogenetic analysis indicated that some cyanobacterial isolates could be accommodated to genus or order level. The 16S rRNA sequence analysis data in this study confirmed that order Nostocales and order Pleurocapsales cyanobacteria are monophyletic while orders Chroococcales, Oscillatoriales and Stigonematales cyanobacteria are polyphyletic. Polyphasic approach including the combination of light microscopy, cultures and the analysis of 16S rRNA gene sequences provide a promising approach to ascertain the diversity of cyanobacteria in different habitats.

마그네슘 다이캐스팅 합금내 불순물의 정량적 평가 (The Quantitative Evaluation for Impurities of Magnesium Diecasting Alloys)

  • 김현식;예대희;강민철;손근용;정해용
    • 한국주조공학회지
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    • 제34권1호
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    • pp.14-21
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    • 2014
  • Magnesium and its alloys are being applied to various kinds of industrial fields, especially their use on automotive parts and electronic part. These parts are manufactured mainly through diecasting process and magnesium ingots are used as raw materials. In the case that ingot quality is not secured, massive casting defects can occur and some manufactures can be damaged by the defects. This study is to evaluate ingots' cleanliness of magnesium alloys. It includes composition analysis by spectrometer, measurement of inclusion contents by SEM, brightness test on fractured surface and etc. Especially, the brightness test is a very easy and quick evaluation method. The brightness becomes low when the amount of oxides or inclusions on the surface increases. The brightness test data have been compared with those obtained from other methods for measuring the mount of impurities, which showed good relationship between the brightness and the others. Thus, the brightness test could be a promising method to measure the cleanliness of magnesium alloys.

유기물 광전소자 제작을 위한 박스 캐소드 스퍼터 기술 (Box Cathode Sputtering Technologies for Organic-based Optoelectronics)

  • 김한기
    • 한국전기전자재료학회논문지
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    • 제19권4호
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    • pp.373-378
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    • 2006
  • We report on plasma damage free-sputtering technologies for organic light emitting diodes (OLEDs), organic thin film transistor (OTFT) and flexible displays by using a box cathode sputtering (BCS) method. Specially designed BCS system has two facing targets generating high magnetic fields ideally entering and leaving the targets, perpendicularly. This target geometry allows the formation of high-density plasma between targets and enables us to realize plasma damage free sputtering on organic layer without protection layer against plasma. The OLED with Al cathode prepared by BCS shows electrical and optical characteristics comparable to OLED with thermally evaporated Mg-Ag cathode. It was found that OLED with Al cathode layer prepared by BCS has much lower leakage current density ($1{\times}10^{-5}\;mA/cm^2$ at -6 V) than that $(1{\times}10^{-2}{\sim}-10^0\;mA/cm^2)$ of OLED prepared by conventional DC sputtering system. This indicates that BCS technique is a promising electrode deposition method for substituting conventional thermal evaporation and DC/RF sputtering in fabrication process of organic based optoelectronics.

Spatio-temporal Query Processing Systems for Ubiquitous Environments

  • Kim, Jeong Joon;Kang, Jeong Jin;Rothwell, Edward J.;Lee, Ki Young
    • International Journal of Internet, Broadcasting and Communication
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    • 제5권2호
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    • pp.1-4
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    • 2013
  • With the recent development of the ubiquitous computing technology, there are increasing interest and research in technologies such as sensors and RFID related to information recognition and location positioning in various ubiquitous fields. Especially, RTLS (Real-Time Locating Services) dealing with spatio-temporal data is emerging as a promising technology. For these reasons, the ISO/IEC published RTLS standard specification for compatibility and interoperability in RTLS. Therefore, in this paper, we designed and implemented Spatio-temporal Query Processing Systems for efficiently managing and searching the incoming Spatio-temporal data stream of moving objects. Spatio-temporal Query Processing Systems's spatio-temporal middleware maintains interoperability among heterogeneous devices and guarantees data integrity in query processing through real time processing of unceasing spatio-temporal data streams and two way synchronization of spatio-temporal DBMSs. Web Server uses the SOAP(Simple Object Access Protocol) message between client and server for interoperability and translates client's SOAP message into CQL(Continuous Query Language) of the spatio-temporal middleware.

BIM기반 실내공간정보구축 및 위치정보 활용 서비스 동향 고찰 (Practices on BIM-based indoor spatial information implementation and location-based services)

  • 김민철;장미경;홍성문;김주형
    • 한국BIM학회 논문집
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    • 제5권3호
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    • pp.41-50
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    • 2015
  • Increasing size and complexity of indoor structures have led to much more complication in the spatial cognition and situational awareness. Contrary to outdoor environments, occupants have limited information regarding the indoor space syntax in terms of architectural and semantic information as well as how they interact with their surroundings. The availability of such information could give conveniences to both users and managers in various aspects. In order to visualize the exact location of rooms and utilities in 3D, many studies and projects have utilized BIM models because of its promising value of representing building components. In fact, the application of BIM provides definitive spatial indoor data and creates services for indoor space management and navigation. Therefore, this paper aims to provide an overview of practices on BIM-based indoor spatial information implementation and location-based services. It is expected that enabling of technologies, data-rich content and accessibility of information products will accelerate the growth of the spatially-related markets in various fields.

Nonbinary Convolutional Codes and Modified M-FSK Detectors for Power-Line Communications Channel

  • Ouahada, Khmaies
    • Journal of Communications and Networks
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    • 제16권3호
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    • pp.270-279
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    • 2014
  • The Viterbi decoding algorithm, which provides maximum - likelihood decoding, is currently considered the most widely used technique for the decoding of codes having a state description, including the class of linear error-correcting convolutional codes. Two classes of nonbinary convolutional codes are presented. Distance preserving mapping convolutional codes and M-ary convolutional codes are designed, respectively, from the distance-preserving mappings technique and the implementation of the conventional convolutional codes in Galois fields of order higher than two. We also investigated the performance of these codes when combined with a multiple frequency-shift keying (M-FSK) modulation scheme to correct narrowband interference (NBI) in power-line communications channel. Themodification of certain detectors of the M-FSK demodulator to refine the selection and the detection at the decoder is also presented. M-FSK detectors used in our simulations are discussed, and their chosen values are justified. Interesting and promising obtained results have shown a very strong link between the designed codes and the selected detector for M-FSK modulation. An important improvement in gain for certain values of the modified detectors was also observed. The paper also shows that the newly designed codes outperform the conventional convolutional codes in a NBI environment.