• Title/Summary/Keyword: advanced characterization

Search Result 1,024, Processing Time 0.029 seconds

Characterization Studies on Data Access Bias in Mobile Platforms

  • Bahn, Hyokyung
    • International journal of advanced smart convergence
    • /
    • v.10 no.4
    • /
    • pp.52-58
    • /
    • 2021
  • Data access bias can be observed in various types of computing systems. In this paper, we characterize the data access bias in modern mobile computing platforms. In particular, we focus on the access bias of data observed at three different subsystems based on our experiences. First, we show the access bias of file data in mobile platforms. Second, we show the access bias of memory data in mobile platforms. Third, we show the access bias of web data and web servers. We expect that the characterization study in this paper will be helpful in the efficient management of mobile computing systems.

Preparation and Characterization of Poly(styrenesulfonic acid)-grafted Fluoropolymer Membrane for Direct Methanol Fuel Cell

  • Choi, Jae-Hak;Kang, Phil-Hyun;Lim, Youn-Mook;Sohn, Joon-Yong;Shin, Jun-Hwa;Jung, Chan-Hee;Jeun, Joon-Pyo;Nho, Young-Chang
    • Korean Membrane Journal
    • /
    • v.9 no.1
    • /
    • pp.52-56
    • /
    • 2007
  • A proton exchange membrane was prepared by ${\gamma}-irradiation-induced$ grafting of styrene into poly(tetrafluoro-ethylene-co-perfluoropropyl vinyl ether) (PFA) and subsequent sulfonation reaction. The degree of grafting (DOG) increased with an increase in the absorbed dose. The prepared membranes showed high ion exchange capacity reaching 3.0 meq/g, which exceeded the performance of commercially available perfluorosulfonic acid membranes such as Nafion. The proton conductivity of PFA-g-PSSA membrane increased with the DOG and reached 0.17 S/cm for the highest sample at room temperature. The DMFC performance of the prepared membranes with 50% DOG was comparable to that of Nafion membrane.

Introduction to the Center for Advanced Meta-Materials (파동에너지극한제어연구단 소개)

  • Lee, Hak-Ju;Kim, Gwang-Seop;Song, Gyeong-Jun;Jeong, Ju-Yeon
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2015.08a
    • /
    • pp.77.1-77.1
    • /
    • 2015
  • The Center for Advanced Meta-Materials (CAMM) was launched in 2014 as a center for Global Frontier Projects supported by the Ministry of Science, ICT and Future Planning. The center is geared towards developing core technologies in controlling wave energies by incorporating creative artificial structures of sub-wavelength sizes. Furthermore, the center not only investigates novel meta-materials and devices but also builds new design, fabrication and application platforms in order to realize these technologies. The center will create new markets in various industries such as national defense, housing and medical care. In order to accomplish its goals, CAMM is composed of three major divisions: the fabrication/characterization technologies and application division, the advanced metamaterials for electromagnetic wave division and the advanced metamaterials for mechanical wave division. The center will concentrate its efforts in bringing innovations to conventional technologies in sectors such as machinery, ICT, energy and biomedical technology by adopting the use of advanced metamaterial systems. In this talk, we will introduce principles of advanced wave control and describe some advanced metamaterials which can provide new solutions for various social problems in future.

  • PDF

NONDESTRUCTIVE/IN-FIELD CHARACTERIZATION OF TENSILE PROPERTIES AND RESIDUAL STRESS OF WELDED STRUCTURES USING ADVANCED INDENTATION TECHNIQUE

  • Park, Yeol;Dongil Son;Kim, Kwang-Ho;Park, S. Joon;Jang, Jae-il;Dongil Kwon
    • Proceedings of the KWS Conference
    • /
    • 2002.10a
    • /
    • pp.668-674
    • /
    • 2002
  • Structural integrity assessment is indispensable for preventing catastrophic failure of industrial structures/components/facilities. This diagnosis of operating components should be done periodically for safe maintenance and economical repair. However, conventional standard methods for mechanical properties have the problems of bulky specimen, destructive and complex procedure of specimen sampling. Especially, the mechanical properties at welded zone including weldment and heat affected zone could not be evaluated individually due to their size requirement problem. So, an advanced indentation technique has been developed as a potential method for non-destructive testing of in-field structures. This technique measures indentation load-depth curve during indentation and analyzes the mechanical properties related to deformation such as yield strength, tensile strength and work-hardening index. Also indentation technique can evaluate a residual stress based on the concept that indentation load-depth curves were shifted with the direction and the magnitude of residual stress applied to materials. In this study, we characterized the tensile properties and welding residual stress of various industrial facilities through the new techniques, and the results are introduced and discussed.

  • PDF

Growth and characterization of ZnO hybrid structure grown by MOCVD (MOCVD로 성장된 ZnO 하이브리드 구조의 합성과 특성 분석)

  • Choi, Mi-Gyung;Park, Ji-Woong;Kim, Joo-Hui;Min, Hae-Jung;Heo, Han-Na;Kim, Dong-Chan;Kong, Bo-Hyun;Cho, Hyung-Koun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2007.06a
    • /
    • pp.420-420
    • /
    • 2007
  • ZnO 나노막대는 산화물 반도체로서 넓은 밴드캡 (3.37eV)을 가진 반도체이며, 테라급의 전계 효과 트랜지스터(FET), 대기오염물질 모니터링 센서, 태앙전지용 전극, UV 발광소자, 전계방출 디스플레이의 팀 등 나노기술 전반에 활용해 최근 각광을 받고 있는 물질이다. 최근 디바이스 응용의 효율을 높이기 위한 방편으로 나노막대에서 박막으로의 연구가 활발하다. 본 실험은 MOCVD률 이용하여 p-si 기판위에 나노막대를 성장시킨 후 압력 및 온도 등의 공정변수를 조절하여 나노막대에서 박막으로 성장형태를 변화시켰다. SEM으로 1 차원 나노막대에서 2차원의 나노박막으로 성장이 된 ZnO 하이브리드 구조를 확인할 수 있었다. 또, PL장비를 이용해 ZnO의 UV영역의 파장을 확인할 수 있었다.

  • PDF

Morphological, Physical Characterization of Poly(acrylic acid) Nanogel Prepared by Electron Beam Irradiation

  • Park, Jong-Seok;Choi, Jong-Bae;Gwon, Hui-Jeong;Lim, Youn-Mook;Jeong, Sung-In;Shin, Young-Min;Kang, Phil-Hyun;Nho, Young-Chang
    • Journal of Radiation Industry
    • /
    • v.8 no.1
    • /
    • pp.29-34
    • /
    • 2014
  • Nanogels are internally cross-linked particles of sub-micrometer size made of hydrophilic polymers and are considered a distinct type of macromolecules, compared with linear and branched polymers or macroscopic gels. In this study, we studied a method of radiation induced synthesis of nanogels, which allows us to obtain tailored intra-molecularly crosslinked macromolecules of independently chosen molecular weight and dimensions. Thus, we report the possibility of applying the prepared nanogels using poly(acrylic acid) through electron beam irradiation for potential application as biomaterials. The nanogels were characterized by scanning electron microscopy (SEM). In addition, the size and zeta-potential of nanogels were measured by a particle size analyzer (PSA). The nanogels were prepared at an approximate size of 180 nm at 100 kGy and were spherical in shapes. The size of the nanogels decreased with increasing irradiation doses, and the absolute value of zeta potential increased with increasing irradiation doses.

Fabrication and Characterization of Ru/Ni Substrates for Superconductor Applications (고온 초전도체를 위한 Ru/Ni 기판의 제조와 특성 분석)

  • Kwangsoo No;Huyong Tian;Inki Hong;Hyunsuk Hwang;Tae-Hyun Sung
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
    • /
    • 2002.02a
    • /
    • pp.13-16
    • /
    • 2002
  • Ru thin films were deposited on bi-axially textured Ni tape using rf-magnetron sputtering for a conductive buffer layer of high Tc superconductor applications. (002) textured Ni films were fabricated as the deposition temperature was over $600^{\circ}C$. Rocking curves of the films showed similar alignment to those the Ni tapes. The resistivity of the tapes fabricated below $600^{\circ}C$ was around 20$\mu\Omega$-cm which is good for the conductive layer for tape superconductor applications.

  • PDF