• 제목/요약/키워드: Shift point

검색결과 507건 처리시간 0.027초

Applicability of Geo-spatial Processing Open Sources to Geographic Object-based Image Analysis (GEOBIA)

  • Lee, Ki-Won;Kang, Sang-Goo
    • 대한원격탐사학회지
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    • 제27권3호
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    • pp.379-388
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    • 2011
  • At present, GEOBIA (Geographic Object-based Image Analysis), heir of OBIA (Object-based Image Analysis), is regarded as an important methodology by object-oriented paradigm for remote sensing, dealing with geo-objects related to image segmentation and classification in the different view point of pixel-based processing. This also helps to directly link to GIS applications. Thus, GEOBIA software is on the booming. The main theme of this study is to look into the applicability of geo-spatial processing open source to GEOBIA. However, there is no few fully featured open source for GEOBIA which needs complicated schemes and algorithms, till It was carried out to implement a preliminary system for GEOBIA running an integrated and user-oriented environment. This work was performed by using various open sources such as OTB or PostgreSQL/PostGIS. Some points are different from the widely-used proprietary GEOBIA software. In this system, geo-objects are not file-based ones, but tightly linked with GIS layers in spatial database management system. The mean shift algorithm with parameters associated with spatial similarities or homogeneities is used for image segmentation. For classification process in this work, tree-based model of hierarchical network composing parent and child nodes is implemented by attribute join in the semi-automatic mode, unlike traditional image-based classification. Of course, this integrated GEOBIA system is on the progressing stage, and further works are necessary. It is expected that this approach helps to develop and to extend new applications such as urban mapping or change detection linked to GIS data sets using GEOBIA.

Engineering Cellulose Fibers for High-Value Added Products for Pulp & Paper Industry

  • Ko, Young Chan;Park, Jong-Moon
    • 펄프종이기술
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    • 제47권6호
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    • pp.22-40
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    • 2015
  • Cellulose fibers is one of the most abundant in nature. It has many distinctive features: abundant in nature, biodegradable, non-toxic, eco-friendly, sustainable, easy to fabricate, hydrophilic, and cost-effective. Cellulose fibers, known as pulp, is produced from cellulose-containing materials by the pulping process. As the raw material, wood has been most commonly used while recycled pulp has been also used to some degree. Thus, pulp usually refers to wood pulp. Generally, the pulp and paper industry is regarded as the commodity market where the cost should be much more important than the quality. It also belongs to a mature market where the growth is slow, or even in decline. Accordingly, technological development has been rather stagnant for the industry. Recently, however, the pulp and paper industry has faced very serious challenges. First, due to digital technology, there has been a steady decline in the need for pulp and paper products. The digital industry has continuously replaced printed products such as books, newspapers, and magazines. Second, there has been a trend initiated by developed countries to limit the use of wood as the raw material for the sake of environmental protection. This forces the industry to find a more efficient use of wood pulp as well as finding alternative, non-wood sources. Third, as an individual becomes wealthier and more conscious of health-care, the quality of a product becomes more important than the cost. Thus, a paradigm shift is needed from the cost-conscientious to the quality conscientious. The objective of this article is to review the technologies aimed at engineering cellulose fibers for producing high-value added paper products.

A Preliminary Research on Optical In-Situ Monitoring of RF Plasma Induced Ion Current Using Optical Plasma Monitoring System (OPMS)

  • Kim, Hye-Jeong;Lee, Jun-Yong;Chun, Sang-Hyun;Hong, Sang-Jeen
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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    • pp.523-523
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    • 2012
  • As the wafer geometric requirements continuously complicated and minutes in tens of nanometers, the expectation of real-time add-on sensors for in-situ plasma process monitoring is rapidly increasing. Various industry applications, utilizing plasma impedance monitor (PIM) and optical emission spectroscopy (OES), on etch end point detection, etch chemistry investigation, health monitoring, fault detection and classification, and advanced process control are good examples. However, process monitoring in semiconductor manufacturing industry requires non-invasiveness. The hypothesis behind the optical monitoring of plasma induced ion current is for the monitoring of plasma induced charging damage in non-invasive optical way. In plasma dielectric via etching, the bombardment of reactive ions on exposed conductor patterns may induce electrical current. Induced electrical charge can further flow down to device level, and accumulated charges in the consecutive plasma processes during back-end metallization can create plasma induced charging damage to shift the threshold voltage of device. As a preliminary research for the hypothesis, we performed two phases experiment to measure the plasma induced current in etch environmental condition. We fabricated electrical test circuits to convert induced current to flickering frequency of LED output, and the flickering frequency was measured by high speed optical plasma monitoring system (OPMS) in 10 kHz. Current-frequency calibration was done in offline by applying stepwise current increase while LED flickering was measured. Once the performance of the test circuits was evaluated, a metal pad for collecting ion bombardment during plasma etch condition was placed inside etch chamber, and the LED output frequency was measured in real-time. It was successful to acquire high speed optical emission data acquisition in 10 kHz. Offline measurement with the test circuitry was satisfactory, and we are continuously investigating the potential of real-time in-situ plasma induce current measurement via OPMS.

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Solar Photovoltaics Technology: No longer an Outlier

  • Kazmerski, Lawrence L.
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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    • pp.70-70
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    • 2011
  • The prospects of current and coming solar-photovoltaic (PV) technologies are envisioned, arguing this solar-electricity source is beyond a tipping point in the complex worldwide energy outlook. Truly, a revolution in both the technological advancements of solar PV and the deployment of this energy technology is underway; PV is no longer an outlier. The birth of modern photovoltaics (PV) traces only to the mid-1950s, with the Bell Telephone Laboratories' development of an efficient, single-crystal Si solar cell. Since then, Si has dominated the technology and the markets, from space through terrestrial applications. Recently, some significant shift toward technology diversity have taken place. Some focus of this presentation will be directed toward PV R&D and technology advances, with indications of the limitations and relative strengths of crystalline (Si and GaAs) and thin-film (a-Si:H, Si, Cu(In,Ga)(Se,S)2, CdTe). Recent advances, contributions, industry growth, and technological pathways for transformational now and near-term technologies (Si and primarily thin films) and status and forecasts for next-generation PV (nanotechnologies and non-conventional and "new-physics" approaches) are evaluated. The need for R&D accelerating the now and imminent (evolutionary) technologies balanced with work in mid-term (disruptive) approaches is highlighted. Moreover, technology progress and ownership for next generation solar PV mandates a balanced investment in research on longer-term (the revolution needs revolutionary approaches to sustain itself) technologies (quantum dots, multi-multijunctions, intermediate-band concepts, nanotubes, bio-inspired, thermophotonics, ${\ldots}$ and solar hydrogen) having high-risk, but extremely high performance and cost returns for our next generations of energy consumers. This presentation provides insights to the reasons for PV technology emergence, how these technologies have to be developed (an appreciation of the history of solar PV)-and where we can expect to be by this mid-21st century.

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초등수학에서 측정활동에 기반한 소수의 학습.지도 방안 및 학생의 이해 실태 분석 (A Construction of 'Decimal Fraction' Unit of Elementary Mathematics Textbook and Analysis of Students' State of Understanding Based on Measurement Activity)

  • 김은정;강흥규
    • 한국초등수학교육학회지
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    • 제18권1호
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    • pp.37-62
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    • 2014
  • 소수 개념은 측정수, 십진기수법, 분수, 비, 작용소, 통약 불가능성, 무한근사, 실무한, 계산수 등 여러 측면을 가지고 있지만, 이 소수 개념의 요소들은 분리될 수 있는 것이라기보다는 단위의 세분할에 의한 측정활동에 복합적으로 내재되어 있다. 요컨대 소수 지도의 핵심은 측정활동이며, 소수의 개념 지도를 위해서는 자연수, 분수와의 관계 이해와 십진기수법적인 자리체계를 명확히 이해시키는 것이 중요하며 그 수단으로 측정활동이 강조되어야 한다. 이 논문에서는 측정활동을 방법으로 소수에 내포된 여러 개념들을 통합적으로 이해시킬 수 있는 학습 지도안을 구성하고, 그에 따른 학생들의 이해 실태를 분석하고자 한다.

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한국산 씀바귀의 Flavonoid 성분에 관한 연구 (Flavonoidal constituent in Korean Lactuca dentata Makino)

  • 정강현;윤광로;김준평
    • 한국식생활문화학회지
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    • 제9권2호
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    • pp.131-136
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    • 1994
  • 한국산 씀바귀(Lactuca dentata Makino)의 ethylacetate 추출물에서 6 종류의 flavonoid 성분이 TLC에 의해서 검출 되었으며, 이들은 극성에 따라서 A에서 F가지 명명되었다. 그들 중 주성분으로 생각되는 물질 E를 column chromatography을 이용하여 분리정제 하였다. 물질 E의 녹는 점은 $249.5^{\circ}C-251^{\circ}C$ 로 나타났으며, 그 구조를 밝히기 위하여, 물질 E와 이를 가수분해한 genin에 대한 여러가지 shift reagent에서 UV와 IR분석을 하고 또한 물질 E와 그의 acetyl 유도체에 대한 NMR 분석을 하였으며 물질 E에 결합된 당은 TLC에 의하여 확인하였다. 이와같은 분석 결과에서 물질 E는 luteolin 모핵에 glucose가 결합된 $luteolin-7-0-{\beta}-D-glucoside$로서 확인되었다.

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디지털 텍스타일 프린팅 시스템에 기반을 둔 의류디자인 프로세스 연구 (A Study on the Fashion Design Process Based on the Digital Textile Printing System)

  • 이지원;이주현
    • 한국감성과학회:학술대회논문집
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    • 한국감성과학회 2002년도 추계학술대회 논문집
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    • pp.85-96
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    • 2002
  • 본 연구에서는 ‘대량 맞춤화(Mass Customization)' 트렌드의 부상과 그 맥락을 같이 하여, 텍스타일 분야의 혁명이라 일컬어지는 디지털 텍스타일 프린팅 기술을 기반으로 한 소비자 참여형 의류 디자인 프로세스 모형 두 가지를 제안하고, 기존의 고전적인 디자인 프로세스와 이 모형들 사이의 효율성, 적합성을 비교 고찰함으로써, 대량 맞춤화 시대를 위한 새로운 의류 디자인 프로세스의 가능성을 모색하였다. 20대∼30대 여성을 대상으로 설문조사를 실시한 결과, 전체 응답자들은 선택의 기회를 가장 많이 가질 수 있는 대량 맞춤화형 디자인 프로세스를 가장 선호하였으며, 응답자들은 의류 소재의 디자인 요소 중에서 문양보다는 색채의 영향을 더 많이 받는 것으로 나타났다. 본 연구의 결과를 통하여 획일화되고 대량화된 상품보다는 보다 차별화되고 자신의 요구를 반영한 상품을 선호하는 소비자들의 수요를 발견하였으며 이에 부응하는 디자인 프로세스로의 패러다임 변화에 관한 지표를 얻을 수 있었다.

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Application of portable digital radiography for dental investigations of ancient Egyptian mummies during archaeological excavations: Evaluation and discussion of the advantages and limitations of different approaches and projections

  • Seiler, Roger;Eppenberger, Patrick;Ruhli, Frank
    • Imaging Science in Dentistry
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    • 제48권3호
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    • pp.167-176
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    • 2018
  • Purpose: In the age of X-ray computed tomography (CT) and digital volume tomography (DVT), with their outstanding post-processing capabilities, indications for planar radiography for the study of the dentition of ancient Egyptian mummies may easily be overlooked. In this article, the advantages and limitations of different approaches and projections are discussed for planar oral and maxillofacial radiography using portable digital X-ray equipment during archaeological excavations. Furthermore, recommendations are provided regarding projections and sample positioning in this context. Materials and Methods: A total of 55 specimens, including 19 skeletonized mandibles, 14 skeletonized skulls, 18 separate mummified heads, and 4 partially preserved mummies were imaged using portable digital X-ray equipment in the course of archaeological excavations led by the University of Basel in the Valley of the Kings between 2009 and 2012. Images were evaluated by 2 authors with regard to the visibility of diagnostically relevant dental structures using a 4-point grading system(Likert scale). Results: Overall, the visibility of diagnostically relevant dental structures was rated highest by both authors on X-ray images acquired using a dental detector. The tube-shift technique in the lateral projections of mandibular dentition achieved the second-best rating, and lateral projections achieved the third-best rating. Conclusion: Conventional planar digital X-ray imaging, due to its ubiquity, remains an excellent method-and often the only practicable one-for examining the skulls and teeth of ancient Egyptian mummies under field conditions. Radiographic images of excellent diagnostic quality can be obtained, if an appropriate methodology regarding the selected projections and sample placement is followed.

Mo 유연기판을 이용한 Cu2SnS3 박막 태양전지의 셀레늄 도핑 효과 (Effect of Selenium Doping on the Performance of Flexible Cu2SnS3(CTS) Thin Film Solar Cells)

  • 이인재;조은애;장준성;이병훈;이동민;강창현;문종하
    • 한국재료학회지
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    • 제30권2호
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    • pp.68-73
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    • 2020
  • Due to its favorable optical properties, Cu2SnS3 (CTS) is a promising material for thin film solar cells. Doping, which modifies the absorber properties, is one way to improve the conversion efficiency of CTS solar cells. In this work, CTS solar cells with selenium doping were fabricated on a flexible substrate using sputtering method and the effect of doping on the properties of CTS solar cells was investigated. In XRD analysis, a shift in the CTS peaks can be observed due to the doped selenium. XRF analysis confirmed the different ratios of Cu/Sn and (S+Se)/(Cu+Sn) depending on the amount of selenium doping. Selenium doping can help to lower the chemical potential of sulfur. This effectively reduces the point defects of CTS thin films. Overall improved electrical properties were observed in the CTS solar cell with a small amount of selenium doping, and a notable conversion efficiency of 1.02 % was achieved in the CTS solar cell doped with 1 at% of selenium.

Reduced graphene oxide field-effect transistor for biomolecule detection and study of sensing mechanism

  • Kim, D.J.;Sohn, I.Y.;Kim, D.I.;Yoon, O.J.;Yang, C.W.;Lee, N.E.;Park, J.S.
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제40회 동계학술대회 초록집
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    • pp.431-431
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    • 2011
  • Graphene, two dimensional sheet of sp2-hybridized carbon, has attracted an enormous amount of interest due to excellent electrical, chemical and mechanical properties for the application of transparent conducting films, clean energy devices, field-effect transistors, optoelectronic devices and chemical sensors. Especially, graphene is promising candidate to detect the gas molecules and biomolecules due to the large specific surface area and signal-to-noise ratios. Despite of importance to the disease diagnosis, there are a few reports to demonstrate the graphene- and rGO-FET for biological sensors and the sensing mechanism are not fully understood. Here we describe scalable and facile fabrication of rGO-FET with the capability of label-free, ultrasensitive electrical detection of a cancer biomarker, prostate specific antigen/${\alpha}1$-antichymotrypsin (PSA-ACT) complex, in which the ultrathin rGO sensing channel was simply formed by a uniform self-assembly of two-dimensional rGO nanosheets on aminated pattern generated by inkjet printing. Sensing characteristics of rGO-FET immunosensor showed the highly precise, reliable, and linear shift in the Dirac point with the analyte concentration of PSA-ACT complex and extremely low detection limit as low as 1 fg/ml. We further analyzed the charge doping mechanism, which is the change in the charge carrier in the rGO channel varying by the concentration of biomolecules. Amenability of solution-based scalable fabrication and extremely high performance may enable rGO-FET device as a versatile multiplexed diagnostic biosensor for disease biomarkers.

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