• Title/Summary/Keyword: contact effect

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Hydrogen Spillover Kinetics - I. Effect of Surface Morphology on [$Pt/MoO_{3}$] Catalyst (수소 spillover 속도론 - I. $Pt/MoO_{3}$ 촉매의 표면 형상 변화)

  • Kim Jin Gul;Kim Seong-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.5 no.6
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    • pp.491-494
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    • 2004
  • [ $H_2$ ] uptake into $Pt/MoO_{3}$ was enhanced with an increased calcination temperature. Selective CO pulse chemisorption demonstrated that free Pt surface area was decreased as calcination temperature was increased. Characteristic techniques were dedicated to elucidate the closer contact at adlineation sites between Pt and $MoO_3$ substrates. Calcination resulted in supplying the hydrogen access into more $MoO_3$ particles and controlling the kinetics of hydrogen uptake.

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Expression of Newer Outer Membrane Proteins (OMPs) Induced by Cephalosporins and Quinolone Group of Antibiotics in Klebsiella pneumoniae

  • KY TO;DANA VAN;SHARMA SAROJ;CHHIBBER SANJAY
    • Journal of Microbiology and Biotechnology
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    • v.15 no.2
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    • pp.421-424
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    • 2005
  • Effect of antibiotics belonging to three different groups, including third generation cephalosporins, aminoglycosides, and quinolones, on the outer membrane protein (OMP) profile of Klebsiella pneumoniae was examined. It was found that a new OMP (porins) of 40 kDa molecular mass was expressed in Klebsiella pneumoniae, when grown in the presence of ceftazidime, whereas new proteins with 30 kDa and 22 kDa masses were detected in the presence of ofloxacin. The immunoblot analysis showed that the new proteins of 40 kDa and 30 kDa molecular masses were expressed on the outer envelope, when being exposed to antibiotics ceftazidime and ofloxacin, respectively. This finding is important, as the outer surface comes in contact with the immune system, and therefore may have a bearing on the outcome of the disease.

Study on the moving device of press machine for forming impact reduction (성형충격 저감을 위한 프레스 구동기구에 관한 연구)

  • Kim, Jeong-Eon;Hong, Seok-Kwan;Kim, Jong-Deok;Heo, Young-Moo;Cho, Chong-Du;Kang, Jeong-Jin
    • Design & Manufacturing
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    • v.2 no.4
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    • pp.11-15
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    • 2008
  • In the sheet metal forming using a high speed press machine, driving device, such as crank, link, and knuckle mechanism, has to be designed in consideration of impact at a moment when press die contact with material, because the impact affects a dimensional accuracy of products and a life span of press die. In this study, dynamic analysis was performed using numerical simulation in order to verify the impact reduction effect for proposed double knuckle mechanism by estimating rolling and pitching moment of slide.

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Effect of nitrogen doping on properties of plasma polymerized poly (ethylene glycol) film

  • Javid, Amjed;Long, Wen;Lee, Joon S.;Kim, Jay B.;Sahu, B.B.;Jin, Su B.;Han, Jeon G.
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2014.11a
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    • pp.286-288
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    • 2014
  • This study deals with the catalyst free radio frequency plasma assisted polymerization of ethylene glycol using nitrogen as reactive gas to modify the surface chemistry and morphology. The deposited film was characterized through various analysis techniques i.e. surface profilometry, Forier transform infrared spectroscopy, water contact angle and UV-visible spectroscopy to analyze film thickness, chemical structure, surface energy and optical properties respectively. The surface topography was analyzed by Atomic force microscopy. It was observed that the ethylene oxide behaviour and optical transmittance of the film were reduced with the introduction of nitrogen gas due to higher fragmentation of monomer. However the hydrophilic behavior of the film improved due to formation of new water loving functional groups suitable for biomedical applications.

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Effect of electric field on asymmetric degradation in a-IGZO TFTs under positive bias stress (Positive bias stress하에서의 electric field가 a-IGZO TFT의 비대칭 열화에 미치는 영향 분석)

  • Lee, Da-Eun;Jeong, Chan-Yong;Jin, Xiao-Shi;Gwon, Hyeok-In
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2014.11a
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    • pp.108-109
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    • 2014
  • 본 논문에서는 gate와 drain bias stress하에서의 a-IGZO thin-film transistors (TFTs)의 비대칭 열화 메커니즘 분석을 진행하였다. Gate와 drain bias stress하에서의 a-IGZO TFT의 열화 현상은 conduction band edge 근처에 존재하는 oxygen vacancy-related donor-like trap의 발생으로 예상되며, TFT의 channel layer 내에서의 비대칭 열화현상은 source의 metal과 a-IGZO layer간의 contact에 전압이 인가되었을 경우, reverse-biased Schottky diode에 의한 source 쪽에서의 높은 electric field가 trap generation을 가속화시킴으로써 일어나는 것임을 확인할 수 있었다.

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The Effects of Individual Conflicts among Hotel Banquet Employees on the Performance of Management (호텔 웨딩.연회 종사원의 개인 갈등이 경영 성과에 미치는 영향 관계)

  • Kim, Hee-Kee;An, Seong-Geun;Lee, Jun-Jae
    • Culinary science and hospitality research
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    • v.14 no.2
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    • pp.46-60
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    • 2008
  • In the hotel industry, there are the production and consumption of services at the same time, considering direct contact between employees and customers. In this respect, this study was conducted based on more practical factors to grasp employees' feelings and conflicts. The results of this research are as follows. First, individual conflicts among hotel banquet employees influence devotion to the organization which has a direct effect on performance of management. Second, such devotion is closely correlated with the factors of the performance of management. Finally, managing employees' conflicts is the key factor to promote the performance of management. Under these circumstances, there should be more concern in solving problems among employees and special pro-grams for promoting job satisfaction and devotion which bring about more profits as well as a sense of achievement.

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Alignment property change in DLC alignment layer containing various hydrogen concentration

  • Kim, Jong-Bok;Kim, Kyung-Chan;Ahn, Han-Jin;Hwang, Byung-Har;Baik, Hong-Koo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07a
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    • pp.378-380
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    • 2005
  • Diamond like carbon (DLC) films are known that they show homogeneous alignment property when they are irradiated by Ar ion beam. The DLC films in most of studies were deposited by CVD and contain large mount of hydrogen. In order to identity the hydrogen effect on alignment property, DLC films is deposited by RF magnetron sputter using various ratio of Ar and H2 as reactive gas. DLC films are characterized by FT-IR, Raman and contact angle. Alignment property is estimated by measuring pretilt angle.

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Effects of Ti and TiN Capping Layers on Cobalt-silicided MOS Device Characteristics in Embedded DRAM and Logic

  • Kim, Jong-Chae;Kim, Yeong-Cheol;Choy, Jun-Ho
    • Journal of the Korean Ceramic Society
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    • v.38 no.9
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    • pp.782-786
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    • 2001
  • Cobalt silicide has been employed to Embedded DRAM (Dynamic Random Access Memory) and Logic (EDL) as contact material to improve its speed. We have investigated the influences of Ti and TiN capping layers on cobalt-silicided Complementary Metal-Oxide-Semiconductor (CMOS) device characteristics. TiN capping layer is shown to be superior to Ti capping layer with respect to high thermal stability and the current driving capability of pMOSFETs. Secondary Ion Mass Spectrometry (SIMS) showed that the Ti capping layer could not prevent the out-diffusion of boron dopants. The resulting operating current of MOS devices with Ti capping layer was degraded by more than 10%, compared with those with TiN.

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Electric energy saving system with high speed response to load variation using power-factor correction (부하변동에 속응하는 역률개선형 전력절감시스템)

  • Kim, Tae-Soo;Kang, Hyung-Sik;Joo, Kyung-Don;Lyu, Seung-Heon;Koo, Kyung-Wan;Han, Sang-Ok
    • Proceedings of the KIEE Conference
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    • 2002.07d
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    • pp.2388-2390
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    • 2002
  • Small type electric energy saving system is proposed in this paper. The system improves power factor fastly according to load variation of each customer. Phases of voltage and current are detected as 1[ms] unit. Phase coincident algorithm is applied for power factor improvement. Capacitance is controlled for optimal power factor correction. Series reactor is controlled for harmonics reduction. Non-contact device is used for fast response and long life. Test result shows the effect of this system. Power factor of 40[W] electric fan is improved from 95[%] to 100[%]. In the case of electric light, power factor is improved from 82[%] to 100[%]. Response time for load variation is less than 1[ms].

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Magnetic Characteristics of an InSb Hall Device of Multilayerd Structure (다충구조 InSb 홀소자의 제작과 특성)

  • 이우선;김상용;서용진;박진성;김창일
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.8
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    • pp.681-687
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    • 2000
  • Magnetic Characteristics of an InSb hall device of multilayered structures were investigated. For the measurement of electrical properties of the hall device InSb thin films fabricated with series and parallel multilayers wee evaporated. Hall coefficient hall mobility carrier density and hall voltage were measured as a function of the intensity of magnetic field. We found that the XRD analysis of InSb thin film showed good properties at 20$0^{\circ}C$ 60 minutes. Resistance of ohmic contact was increased linearly due to increasing current. Hall voltages at 0.01 T showed 5$\times$10$^{-4}$ [V] and $1.5\times$10$^{-3}$ [V]. Some of device fabrication technique and analysis of magnetic characteristics were discussed.

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