• Title/Summary/Keyword: Passive Layer

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PDAODMRP: An Extended PoolODMRP Based on Passive Data Acknowledgement

  • Cai, Shaobin;Yang, Xiaozong;Wang, Ling
    • Journal of Communications and Networks
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    • v.6 no.4
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    • pp.362-375
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    • 2004
  • An ad hoc network is a multi-hop wireless network. Its limited bandwidth and frequently changing topology require that its protocol should be robust, simple, and energy conserving. We have proposed PoolODMRP to reduce its control overhead greatly by its one-hop local route maintenance. However, PoolODMRP still has some shortcomings. In this paper, we propose PDAODMRP (passive data acknowledgement ODMRP) to extend PoolODMRP. Compared with PoolODMRP, PDAODMRP has the following contributions: (1) It knows the status of its downstream forwarding nodes by route information collected from data packets instead of BEACON signal of MAC layer; (2) it max simplifies the route information collected from data packets by pool nodes; (3) it adopts a dynamic local route maintenance to enforce its local route maintenance; (4) it adopts the route evaluation policy of NSMP (neighbor supporting multicast protocol). Compared with PoolODMRP, PDAODMRP has lower control overhead, lower data delivery delay, and lower data overhead.

A Study on the Cleaning of AISI 304 Stainless Steel Surface for Gold Plating (금도금을 위한 AISI 304 스테인레스강 표면의 세정)

  • 한범석;장현구
    • Journal of the Korean institute of surface engineering
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    • v.28 no.1
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    • pp.23-33
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    • 1995
  • AISI 304 stainless steel has high resistance to corrosion due to the presence of a self-healing chromium oxide film on the surface, which also accounts for the difficulty in plating. Surface cleaning of this alloy is of fundamental importance in gold plating since its effectiveness puts an upper limit on the quality of the final coating. The cleaning of AISI 304 stainless steel was investigated with elimination of artificial passive oxide film and degreasing of remaining buffing wax as stearic acid. The familiar cleaning methods i.e. ultrasonic cleaning, electro-cleaning and activation treatment were fabricated in this study. Activation treatment showed best cleaning efficiency for elimination of passive oxide film among these methods, which was also confirmed by AES (Auger electron spectrometer) analysis. However, the best condition of cleaning was obtained by combining these methods. Electrocleaning time, for degreasing the stearic acid layer, was decreased with increasing amount of added KCN.

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정전위법에 의한 Alloy 600의 입계응력부식균열 거동 연구

  • 맹완영;강영환;일본명
    • Proceedings of the Korean Nuclear Society Conference
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    • 1996.05c
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    • pp.111-116
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    • 1996
  • IGSCC(Intergranular stress corrosion cracking) behaviors of Alloy 600 were studied by the electrchemical ten methods of controlling specimens electrode potentials in the active-passive transition region of anodic polarization curve. Anodic polarization and static potential tests of stressed C-ring type MA Alloy 600 were carried out in 10% NaOH at 300 $^{\circ}C$ for 7days. It was confirmed that IGSCC of Alloy 600 was accellerated by maintaining the specimen potential in the susceptible active-passive transition region of anodic polarization curve. An intergranular crack was initiated on the surface area of C-ring specimens where protective oxide layer was broken down. And the depth of the crack growth was about 100 ${\mu}$m during the testing periods.

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Organic Electrophosphorescent Device driven by Organic Thin-Film Transistor (유기 TFT로 구동한 유기 인광발광소자의 연구)

  • Kim, Yun-Myoung;Pyo, Sang-Woo;Kim, Jun-Ho;Shim, Jae-Hoon;Zyung, Tae-Hyung;Kim, Young-Kwan;Kim, Jung-Soo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11b
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    • pp.312-315
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    • 2001
  • Recently organic electroluminescent devices have been intensively investigated for using in full-color flat-panel display. Since the quantum efficiency of electrophosphorescent device decrease rapidly as the luminance increase, it is desirable to operate the electrophosphorescent display with active matrix rather than passive matrix. Here we report the study of driving electrophosphorescent diode with all organic thin film transistor(OTFT). The structure of electrophosphorescent diode is ITO/TPD/BCP:Ir(ppy)$_3$/BCP/Alq$_3$/Li:Al/Al. In OTFT. polymer is used as an insulator and pentacene as an active layer. Detailed performance of the integrated device will be discussed.

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Effects of Oxygen Scavenging Package on the Quality Changes of Processed Meatball Product

  • Shin, Yang-Jai;Shin, Joong-Min;Lee, Youn-Suk
    • Food Science and Biotechnology
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    • v.18 no.1
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    • pp.73-78
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    • 2009
  • Processed meatball products were packaged in a passive package without oxygen scavenger as 1 control and 3 active packages of which have PP-based oxygen scavenger master batch materials (OSMB) of 40, 80, and 100%(w/w) in the middle layer and stored at 23 and $30^{\circ}C$ up to 9 months. Quality changes of packaged products were evaluated by measuring the oxygen concentration of the headspace in containers, thiobarbituric acid (TBA), color, and flavor. The oxygen concentration of the package having 100% OSMB was lower than those of 40 and 80%. The color changes and TBA values of the meat ball in the package containing 100% OSMB were the least among the treatments. Using principal component analysis (PCA), the control showed more flavor change than the packages containing oxygen scavenger. As a result, all active packages could extend the shelf life of the meatball products compared with that of the passive package.

Organic Electrophosphorescent Device driven by Organic Thin-Film Transistor (유기 TFT로 구동한 유기 인광발광소자의 연구)

  • 김윤명;표상우;김준호;심재훈;정태형;김영관;김정수
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11a
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    • pp.312-315
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    • 2001
  • Recently organic electroluminescent devices have been intensively investigated for using in full-color flat-panel display. Since the quantum efficiency of electrophosphorescent device decrease rapidly as the luminance increase, it is desirable to operate the electrophosphorescent display with active matrix rather than passive matrix. Here we report the study of driving electrophosphorescent diode with all organic thin film transistor(OTFT). The structure of electrophosphorescent diode is ITO/TPD/BCP:Ir(ppy)$_3$/BCP/Alq$_3$/Li:Al/Al. In OTFT, Polymer is used as an insulator and pentacene as an active layer. Detailed performance of the integrated device will be discussed.

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Effect of a Frontal Impermeable Layer on the Excess Slurry Pressure during the Shield Tunnelling (전방 차수층이 쉴드터널 초과 이수압에 미치는 영향)

  • Lee, Yong-Jun;Lee, Sang-Duk
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.1199-1213
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    • 2011
  • Slurry type shield would be very effective for the tunnelling in a sandy ground, but low slurry pressure could cause a tunnel face failure or a ground settlement in front of the tunnel face. Thus, the stability of tunnel face could be maintained by applying an excess slurry pressure that is larger than the active earth pressure. However, the slurry pressure should increase properly because an excessively high slurry pressure could cause the slurry flow out or the passive failure of the frontal ground. It is possible to apply the high slurry pressure without passive failure if a horizontal impermeable layer is located in the ground in front of the tunnel face, but its location, size, and effects are not clearly known yet. In this research, two-dimensional model tests were carried out in order to find out the effect of a horizontal impermeable layer for the slurry shield tunnelling in a saturated sandy ground. As results, larger slurry pressure could be applied to increase the stability of the tunnel face when the impermeable layer was located in the ground above the crown in front of the tunnel face. The most effective length of the impermeable grouting layer was 1.0~1.5D, and the location was 1.0D above the crown level. The safety factor could be suggested as the ratio of the maximum slurry pressure to the active earth pressure at the tunnel face. It could also be suggested that the slurry pressure in the magnitude of 3.5~4.0 times larger than the active earth pressure at the initial tunnel face could be applied if the impermeable layer was constructed at the optimal location.

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Effects of F-treatment on the Degradation of $Mg_2$Ni type Hydrogen Storage Alloy Electrode ($Mg_2$Ni계 수소저장합금전극의 퇴화거동에 미치는 불화 처리 영향)

  • Kim, Jun-Seong;Choe, Jae-Ung;Lee, Chang-Rae;Gang, Seong-Gun
    • Korean Journal of Materials Research
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    • v.11 no.4
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    • pp.294-299
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    • 2001
  • Effects of the surface fluorination on the electrochemical charge-discharge properties of $Mg_2$Ni electrode in Ni-MH batteries fabricated by mechanical alloying were investigated. After 20h ball milling, Mg and Ni powder formed nanocrystalline $Mg_2$Ni. Discharge capacity of this alloy increased greatly at first one cycle, but due to the formation of Mg(OH)$_2$ passive layer, it showed a rapid degradation in alkaline solution within 10cyc1es. In case of 6N KOH +xN KF electrolyte (x = 0.5, 1, 2), a continuous and stable fluorinated layer formed by adding excess F$^{[-10]}$ ion, increased durability of $Mg_2$Ni electrode greatly and high rate discharge capability(90-100mAh/g). 2N KF addition led to the highest durability of all tested here. The reason of the improvement is due to thin MgF$_2$, which can prevent the $Mg_2$Ni electrode from forming Mg(OH)$_2$layer that is the main cause of degradation.

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The Effect of Post Oxidation on Corrosion Characteristics of Gas Nitrocarburised Carbon Steels (Nitrocarburising 처리된 탄소강의 내식특성에 미치는 Post Oxidation 효과)

  • Kim, Y.H.;Jung, K.H.
    • Journal of the Korean Society for Heat Treatment
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    • v.12 no.1
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    • pp.9-20
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    • 1999
  • The effect of post oxidation, water-quenched after holding in air for 5~420 seconds or cooling or furnace cooling, on corrosion resistance and phase formation characteristics of the surface layer of SM20C and SM45C carbon steels after gas nirtrocarbursing in the $NH_3-5%CO_2-N_2$ gas atmosphere at $580^{\circ}C$ for 3hours is studied. The compound layers of two steels consist of ${\varepsilon}-Fe_{2-3}N$, ${\gamma}^{\prime}-Fe_4N$ and $Fe_3O_4$, phases, however, the quantity of ${\gamma}^{\prime}-Fe_4N$ phase increases for the furnace cooled specimen compared to that of air cooling specimen. With increasing $NH_3$ content in the gas mixture and also increasing the keeping time in the air after gas nitrocarburising, the ${\varepsilon}-Fe_{2-3}N$ phase of compound layer increases, while the decreased current density recognizing the improvement of corrosion resistance are shown. the passive current density of SM45C steel is lower than that of SM20C steel at the same nitrocarburising conditions.

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The Cu-CMP's features regarding the additional volume of oxidizer to W-Slurry (W-slurry의 산화제 첨가량에 따른 Cu-CMP특성)

  • Lee, Woo-Sun;Choi, Gwon-Woo;Seo, Young-Jin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.07a
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    • pp.370-373
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    • 2003
  • As the integrated circuit device shrinks to the smaller dimension, the chemical mechanical polishing (CMP) process was required for the global planarization of inter-metal dielectric(IMD) layer with free-defect. However, as the IMD layer gets thinner, micro-scratches are becoming as major defects. Chemical-Mechanical Planarization(CMP) of conductors is a key process in Damascene patterning of advanced interconnect structure. The effect of alternative commerical slurries pads, and post-CMP cleaning alternatives are discuess, with removal rate, scratch dentisty, surface roughness, dishing, erosion and particulate density used as performance metrics. Electroplated copper depostion is a mature process from a historical point of view, but a very young process from a CMP persperspective. While copper electrodepostion has been used and stuidied for dacades, its application to Cu damascene wafer processing is only now ganing complete accptance in the semiconductor industry. The polishing mechanism of Cu CMP process has been reported as the repeated process of passive layer formation by oxidizer and abrasion action by slurry abrasives. however it is important to understand the effect of oxidizer on copper pasivation layer in order to obtain higher removal rate and non-uniformity during Cu-CMP process. In this paper, we investigated the effects of oxidizer on Cu-CMP process regarding the additional volume of oxidizer.

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