• 제목/요약/키워드: template-free

검색결과 90건 처리시간 0.03초

Cobalt Oxide Nanorods Prepared by a Template-Free Method for Lithium Battery Application

  • Kim, Seong-Jun;Kim, Eun-Ji;Liu, Meilin;Shin, Heon-Cheol
    • Journal of Electrochemical Science and Technology
    • /
    • 제7권3호
    • /
    • pp.206-213
    • /
    • 2016
  • Transition metal oxide-based electrodes for lithium ion batteries have recently attracted much attention because of their high theoretical capacity. Here we report the electrochemical behavior of cobalt oxide nanorods as anodes, prepared by a template-free, one-step electrochemical deposition of cobalt nanorods, followed by an oxidation process. The as-deposited cobalt has a slightly convex columnar structure, and controlled thermal oxidation produces cobalt oxides of different Co/O ratios, while the original shape is largely preserved. As an anode in a rechargeable lithium battery, the Co/O ratio has a strong effect on initial capacity and cycling stability. In particular, the one-dimensional Co@CoxOy core shell structure obtained from a mild heat-treatment results in superior cycling stability.

A Revocable Fingerprint Template for Security and Privacy Preserving

  • Jin, Zhe;Teoh, Andrew Beng Jin;Ong, Thian Song;Tee, Connie
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제4권6호
    • /
    • pp.1327-1342
    • /
    • 2010
  • With the wide deployment of biometric authentication systems, several issues pertaining security and privacy of the biometric template have gained great attention from the research community. To resolve these issues, a number of biometric template protection methods have been proposed. However, the design of a template protection method to satisfy four criteria, namely diversity, revocability and non-invertibility is still a challenging task, especially performance degradation when template protection method is employed. In this paper, we propose a novel method to generate a revocable minutiae-based fingerprint template. The proposed method consists of feature extraction from fingerprint minutiae pairs, quantization, histogram binning, binarization and eventually binary bit-string generation. The contributions of our method are two fold: alignment-free and good performance. Various experiments on FVC2004 DB1 demonstrated the effectiveness of the proposed methods.

A Preoperative Marking Template for Deep Inferior Epigastric Artery Perforator Flap Perforators in Breast Reconstruction

  • Miranda, Benjamin H.;Pywell, Matthew;Floyd, David
    • Archives of Plastic Surgery
    • /
    • 제41권2호
    • /
    • pp.171-173
    • /
    • 2014
  • Preoperative perforator marking for deep inferior epigastric artery perforator flaps is vital to the success of the procedure in breast reconstruction. Advances in imaging have facilitated accurate identification and preselection of potentially useful perforators. However, the reported imaging accuracy may be lost when preoperatively marking the patient, due to 'mapping errors', as this relies on the use of 2 reported vectors from a landmark such as the umbilicus. Observation errors have been encountered where inaccurate perforator vector measurements have been reported in relation to the umbilicus. Transcription errors have been noted where confusing and wordy reports have been typed or where incorrect units have been given (millimetres vs. centimetres). Interpretation errors have also occurred when using the report for preoperative marking. Furthermore, the marking process may be unnecessarily time-consuming. We describe a bespoke template, created using an individual computed tomography angiography image, that increases the efficiency and accuracy of preoperative marking. The template is created to scale, is individually tailored to the patient, and is particularly useful in cases where multiple potential suitable perforators exist.

AAO에 의한 나노로드 제작 (Fabrication of nano-rod on AAO template)

  • 보보무로드 하므로구로프;박병현;김인수
    • 한국소성가공학회:학술대회논문집
    • /
    • 한국소성가공학회 2008년도 춘계학술대회 논문집
    • /
    • pp.482-484
    • /
    • 2008
  • Anodic aluminum oxide (AAO) which prepared with two-step anodizing method (with dissimilar solutions) was used as a template to fabricate highly ordered, free standing metal nano-rods. AAO nano-template technique can realize self-organized hexagonal pore structure with nanometer dimension size, it's easy to control pore diameter, length and density by varying anodizing conditions. Ni and Ni/Fe/Cu multi-metal layer nanorods were electrochemically deposited into AAO nano-template by AC voltage in simple sulfate solutions.. The properties of samples are tested by X-ray diffraction (XRD), field emission microscopy (FE-SEM).

  • PDF

Effect of Template Removal on Synthesis of Organic-Inorganic Hybrid Mesoporous MCM-48

  • Zhao, Ya Nan;Li, San Xi;Han, Chong-Soo
    • Bulletin of the Korean Chemical Society
    • /
    • 제33권10호
    • /
    • pp.3196-3202
    • /
    • 2012
  • Post-synthesis is used to synthesize organic hybrid inorganic mesoporous sieves. In this method, the activity and structure of the base sieve are crucial to obtain the definable hybrid materials. The chemical and physical properties of the base can be largely changed either by the final step of its synthesizing processes, by template removal which is accomplished with the oxidative thermal decomposition (burning) method or by solvent extraction method. In this paper we compared two methods for the post-synthesis of organic hybrid MCM-48. When the template was extracted with HCl/alcohol mixture, the final product showed larger pore size, larger pore volume and better crystallinity compared to the case of the thermal decomposition. The reactivity of the surface silanol group of template free MCM-48 was also checked with an alkylsilylation reagent $CH_2=CHSi(OC_2H_5)_3$. Raman and $^{29}Si$ NMR spectra of MCM-48 in the test reaction indicated that more of the organic group was grafted to the surface of the sample after the template was removed with the solvent extraction method. Direct synthesis of vinyl-MCM-48 was also investigated and its characteristics were compared with the case of post-synthesis. From the results, it was suggested that the structure and chemical reactivity can be maintained in the solvent extraction method and that organic grafting after the solvent extraction can be a good candidate to synthesize a definable hybrid porous material.

Template-free Synthesis and Characterization of Spherical Y3Al5O12:Ce3+ (YAG:Ce) Nanoparticles

  • Kim, Taekeun;Lee, Jin-Kyu
    • Bulletin of the Korean Chemical Society
    • /
    • 제35권10호
    • /
    • pp.2917-2921
    • /
    • 2014
  • Cerium-activated yttrium aluminate ($Y_3Al_5O_{12}:Ce^{3+}$) exhibiting a garnet structure has been widely utilized in the production of light emitting diodes (LEDs) as a yellow emitting phosphor. The commercialized yttrium aluminum garnet (YAG) phosphor is typically synthesized by a solid-state reaction, which produces irregular shape particles with a size of several tens of micrometers by using the top-down method. To control the shape and size of particles, which had been the primary disadvantage of top-down synthetic methods, we synthesized YAG:Ce nanoparticles with a diameter of 500 nm using a coprecipitation method under the atmospheric pressure without the use of template or special equipment. The precursor particles were formed by refluxing an aqueous solution of the nitrate salts of Y, Al, and Ce, urea, and polyvinylpyrrolidone (55 K) at $100^{\circ}C$ for 12 h. YAG:Ce nanoparticles were formed by the calcination of precursor particles at $1100^{\circ}C$ for 10 h under atmospheric conditions. The phase identification, microstructure, and photoluminescent properties of the products were evaluated by X-ray powder diffraction, scanning electron microscopy, absorption spectrum and photoluminescence analyses.

3D VISION SYSTEM FOR THE RECOGNITION OF FREE PARKING SITE LOCATION

  • Jung, H.G.;Kim, D.S.;Yoon, P.J.;Kim, J.H.
    • International Journal of Automotive Technology
    • /
    • 제7권3호
    • /
    • pp.361-367
    • /
    • 2006
  • This paper describes a novel stereo vision based localization of free parking site, which recognizes the target position of automatic parking system. Pixel structure classification and feature based stereo matching extract the 3D information of parking site in real time. The pixel structure represents intensity configuration around a pixel and the feature based stereo matching uses step-by-step investigation strategy to reduce computational load. This paper considers only parking site divided by marking, which is generally drawn according to relevant standards. Parking site marking is separated by plane surface constraint and is transformed into bird's eye view, on which template matching is performed to determine the location of parking site. Obstacle depth map, which is generated from the disparity of adjacent vehicles, can be used as the guideline of template matching by limiting search range and orientation. Proposed method using both the obstacle depth map and the bird's eye view of parking site marking increases operation speed and robustness to visual noise by effectively limiting search range.

Controlled interfacial energy for UV-imprinting using resin adhesion to substrates

  • Kim, Jin-Ook;Nam, Yeon-Heui;Chae, G.S.;Chung, In-Jae
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
    • /
    • pp.1622-1624
    • /
    • 2006
  • We introduce a modified UV-imprint lithography, a resin transfer from the template to the substrate. We analyzed this method by considering the surface and interfacial free energies of the template-resinsubstrate system. This technique is purely fast and applicable to large area patterning.

  • PDF

Doping-free Transparent Conducting Schottky Type Heterojunction Solar Cells

  • Kim, Joon-Dong
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
    • /
    • pp.209-209
    • /
    • 2012
  • High-efficient transparent conductive oxide (TCO) film-embedding Si heterojunction solar cells were fabricated. An additional doping was not applied for heterojunction solar cells due to the spontaneous junction formation between TCO films and an n-type Si substrate. Three different TCO coatings were formed by sputtering method for an Al-doped ZnO (AZO) film, an indium-tin-oxide (ITO) film and double stacks of ITO/AZO films. An improved crystalline ITO film was grown on an AZO template upon hetero-epitaxial growth. This double TCO films-embedding Si heterojunction solar cell provided significantly enhanced efficiency of 9.23% as compared to the single TCO/Si devices. The effective arrangement of TCO films (ITO/AZO) provides benefits of a lower front contact resistance and a smaller band offset to Si leading enhanced photovoltaic performances. This demonstrates a potential scheme of the effective TCO film-embedding heterojunction Si solar cells.

  • PDF