• 제목/요약/키워드: S-247

검색결과 1,210건 처리시간 0.034초

MPTMS Treated Au/PDMS Membrane for Flexible and Stretchable Strain Sensors

  • Yang, Seongjin;Lim, Hyun Jee;Jeon, Hyungkook;Hong, Seong Kyung;Shin, Jung Hwal
    • 센서학회지
    • /
    • 제25권4호
    • /
    • pp.247-251
    • /
    • 2016
  • Au/PDMS membranes are widely used to fabricate strain sensors which can detect input signals. An interfacial adhesion between metal films and polydimethylsiloxane (PDMS) substrates is one of the important factors determining the performance of strain sensors, in terms of robustness, reliability, and sensitivity. Here, we fabricate Au/PDMS membranes with (3-mercaptopropyl) trimethoxysilane (MPTMS) treatment. PDMS membranes were fabricated by spin-coating and the thickness was controlled by varying the spin rates. Au electrodes were deposited on the PDMS membrane by metal sputtering and the thickness was controlled by varying sputtering time. Owing to the MPTMS treatment, the interfacial adhesion between the Au electrode and the PDMS membrane was strengthened and the membrane was highly transparent. The Au electrode, fabricated with a sputtering time of 50 s, had the highest gauge factor at a maximum strain of ~0.7%, and the Au electrode fabricated with a sputtering time of 60 s had the maximum strain range among sputtering times of 50, 60, and 120 s. Our technique of using Au/PDMS with MPTMS treatment could be applied to the fabrication of strain sensors.

남녀 대학생의 자녀 영어 교육에 대한 목적과 태도 (Male/female college students' aims of English education and attitudes to English education for their future children)

  • 민하영;이진경
    • 한국생활과학회지
    • /
    • 제17권2호
    • /
    • pp.247-254
    • /
    • 2008
  • The study investigated the relationship between college students' purpose of and their attitude to English education for their future children (EEFFC). The subjects were 244 college students in Daegu/Keoungbok area, 120 males (49.2%) and 124 females (50.8%). The data were analyzed with $X^2$, t-test, Pearson's Correlation, and Regression (using SPSS 12.1). Major findings include: (1)Female students are willing to give English education in their future children's earlier years, and they show more active attitude to EEFFC than male students. (2) The purpose of EEFFC is more deeply correlated to the attitude to EEFFC in the case of male students than female students. (3) Concludingly, the more the subjects think that English education is essential for their future children's successful social career, the more they show positive attitude to English education.

Characterization of the Galvanizing Behavior Depending on Annealing Dew Point and Chemical Composition in Dual-Phase Steels

  • Shin, K.S.;Park, S.H.;Jeon, S.H.;Bae, D.C.;Choi, Y.M.
    • Corrosion Science and Technology
    • /
    • 제9권6호
    • /
    • pp.247-253
    • /
    • 2010
  • The characteristics of selective oxidation prior to hot-dip galvanizing with the annealing atmosphere dew point and chemical composition in dual-phase steels and their effect on the inhibition layer formation relevant to coating adhesion have been studied using a combination of electron microscopic and surface analytical techniques. The annealed and also galvanized samples of 3 kinds of Si/Mn ratios with varied amounts of Si addition were prepared by galvanizing simulator. The dew point was controlled at soaking temperature $800^{\circ}C$ in 15%$H_2$ -85%$N_2$ atmosphere. It was shown that good adhesion factors were mainly uniformity of oxide particle distribution of low number density and low Si/Mn ratio prior to hot-dip galvanizing. Their effect was the greatly reduced coating bare spots and the formation of uniform inhibition layer leading to good adhesion of Zn overlay. The mechanism of good adhesion is suggested by two processes: the formation of inhibition layer on the oxide free surface uncovered with no $SiO_2$-containing particles in particular, and the inhibition layer bridging of oxide particles. The growth of inhibition layer was enhanced markedly by the delayed reaction of Fe and Al with the increase of Si/Mn ratio.

탄탈륨 판재의 어닐링 집합조직과 결정립 크기 (Annealing Textures and Grain Size of Tantalum Sheet)

  • 강전연;박성원;박준영;박성준;송이화;박성택;김광련;오경원
    • 소성∙가공
    • /
    • 제28권5호
    • /
    • pp.247-256
    • /
    • 2019
  • In this study, the development of annealing textures in cold rolled and annealed tantalum sheets was analyzed using electron backscatter diffraction. At $900^{\circ}C$, the textures of the recrystallized grains in the partially and completely recrystallized microstructures displayed significant similarities. The average diameter of the recrystallized grains with ${\gamma}-fiber$ orientations exceeded that of grains with different orientations, and the average growth rates were unrelated to the orientations after an initial stage of recrystallization. Additional cold rolling and annealing was done for controlled initial microstructures and textures inherited from various processes of prior cold rolling and annealing. This second cycle of the process resulted in stronger textures with major ${\gamma}-fiber$ orientations as a result of the enhanced ${\gamma}-fiber$ orientations in the preceding textures. A coarse-grained prior microstructure resulted in a weaker annealing texture than a fine grained one regardless of the stronger previous texture, which was occasioned by the sub-structures of the minor orientations at local deformation inhomogeneities such as sharp in-grain shear bands.

Comparisons Fitness in Implant Abutment between Gas Soldering and Laser Welding

  • Cho, Mi-Hyang;Nam, Shin-Eun
    • International Journal of Clinical Preventive Dentistry
    • /
    • 제14권4호
    • /
    • pp.247-255
    • /
    • 2018
  • Objective: Osseointegration is essential process for successful implants and effects to implant in long term, therefore, passive fitness of good prosthesis is necessary. To make a good prosthesis, at first it should be done a sectioned casting and then joined method of sectioned casting body is recommended. Methods: In this study, to provide the fundamental data on stable connection method for successful implants, the author tested fitness of casting body, and compared difference between gas soldering technique and laser welding technique. Results: In fitness test of 2 abutment (test A, C), gas soldering group's fitness in the opposite part of connection was worse than laser welding group. In fitness test of 3 abutment (test B, D), gap distance was increased both in gas soldering technique and laser welding technique. Gap distance at the connecting part and the opposite part of the abutment in gas soldering technique was worse than laser welding technique and the more additional abutment, the worse gap distance in gas soldering technique. In fitness test of 3 abutment (test B, D), there's little variation in No. 2 abutment when connecting soldering process was done and there's little influence on already soldered connection part when the additional soldering connection was done. Conclusion: On weak loading condition and the part which is needed an accuracy, laser welding technique is more effective and on long-span prosthesis and frequent chewing loading part, laser welding technique is recommended first and applying additional gas soldering technique would be better for making much more successful prosthesis.

섬진강 유역의 하천 생태유량 산정 (Environmental Flow Estimation of Seomjin River Basin)

  • 김현정;강성규;최시중;이동률
    • 한국수자원학회:학술대회논문집
    • /
    • 한국수자원학회 2020년도 학술발표회
    • /
    • pp.247-247
    • /
    • 2020
  • 생태유량은 하천에 서식하는 동·식물 등의 서식처 조건을 고려하여 갈수시에도 최소한의 하천생태계가 유지될 수 있도록 하는 유량이다. 이는 하천의 적정유량으로 적용할 수 있는 생태적 기준의 하나이며 수생생물의 물리적 서식처 적합도를 이용하여 산정할 수 있다. 특히 하천 생태계의 먹이 사슬 상층부에 속하는 어류는 서식처의 물리적 조건에 민감하므로 적절한 유량을 보장해 주는 것이 중요하며, 이러한 이유로 생태유량 산정에 어류의 서식처 조건이 주로 이용된다. 본 연구에서는 다목적댐의 건설과 준설 및 매립 등으로 유황 변동과 하류 염해 피해 등에 의한 하구 생태계 변화 등을 겪고 있는 섬진강 수계를 대상으로 송정, 겸백, 화개 세 지점에 대해 생태유량을 산정하였다. 이 생태유량은 섬진강 수계에서는 직접 측정에 한계가 있어 금강에서 측정된 피라미의 서식처 적합도 지수를 이용하였고, 지점의 하상재료 및 환경 조건을 반영하여 PHABSIM을 이용하여 산정되었다. 그 결과 송정의 최적 생태유량은 8.5㎥/s, 겸백은 2.26㎥/s, 그리고 화개 지점은 36㎥/s로 산정되었다. PHABSIM을 이용한 생태유량 산정 값은 지점에 따라 다소 과대 추정되는 경향이 있기도 하지만, 섬진강 수계의 해수 침투 등에 의한 염해 피해 대책 마련 등을 위해서는 산정된 유지유량을 확보하기 위한 해결 방안이 제시되어야 할 것으로 판단된다.

  • PDF

Buyer's EOQ model for deteriorating products under order-size-dependent delay in payments

  • Shinn Seong-Whan;Song Chang-Yong
    • 대한안전경영과학회:학술대회논문집
    • /
    • 대한안전경영과학회 2002년도 춘계학술대회
    • /
    • pp.243-247
    • /
    • 2002
  • This paper deals with the problem of determining the buyer's economic lot sizing policy for exponentially deteriorating products under trade credit. Assuming that the supplier's credit terms are already known and the length of delay is a function of the buyer's order size, we formulate the mathematical model and the solution algorithm is developed based on the properties of an optimal solution.

  • PDF

Role of artificial intelligence in diagnosing Barrett's esophagus-related neoplasia

  • Michael Meinikheim;Helmut Messmann;Alanna Ebigbo
    • Clinical Endoscopy
    • /
    • 제56권1호
    • /
    • pp.14-22
    • /
    • 2023
  • Barrett's esophagus is associated with an increased risk of adenocarcinoma. Thorough screening during endoscopic surveillance is crucial to improve patient prognosis. Detecting and characterizing dysplastic or neoplastic Barrett's esophagus during routine endoscopy are challenging, even for expert endoscopists. Artificial intelligence-based clinical decision support systems have been developed to provide additional assistance to physicians performing diagnostic and therapeutic gastrointestinal endoscopy. In this article, we review the current role of artificial intelligence in the management of Barrett's esophagus and elaborate on potential artificial intelligence in the future.

A Secure Network for Mobile Wireless Service

  • Peng, Kun
    • Journal of Information Processing Systems
    • /
    • 제9권2호
    • /
    • pp.247-258
    • /
    • 2013
  • A new secure network communication technique that has been designed for mobile wireless services, is presented in this paper. Its network services are mobile, distributed, seamless, and secure. We focus on the security of the scheme and achieve anonymity and reliability by using cryptographic techniques like blind signature and the electronic coin. The question we address in this paper is, "What is the best way to protect the privacy and anonymity of users of mobile wireless networks, especially in practical applications like e-commerce?" The new scheme is a flexible solution that answers this question. It efficiently protects user's privacy and anonymity in mobile wireless networks and supports various applications. It is employed to implement a secure e-auction as an example, in order to show its advantages in practical network applications.