• Title/Summary/Keyword: Direct process

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Determination of the process variables for quality monitoring in direct rolling processes (직접압연 공정에서 품질계측을 위한 공정변수의 선정)

  • 배세철;박영준;조형석
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.1364-1367
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    • 1996
  • Recently, direct rolling process, called as strip casting process, has been interested in to save production cost by reducing forming processes. In direct rolling process, since a steel strip of thickness 1-5(mm) can be produced directly from molten metal, it can eliminate secondary hot rolling process. On the other hand, since many process variables are existed in this process and relation of these variables is very complex, it is difficult to realize the process design and the quality control. In this paper, as first step to overcome above difficulties, the quantitative relationship of the process variables affected to quality of the strip has been carried out through the numerical analysis. Also, we determined the process variable to monitor the quality in the direct rolling process. As a result, we show that the solidification final point, called as Nip point, was related directly to quality of the strip.

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A Study on Direct Cooling and Indirect Cooling in Etching Process Cooling System (식각 공정용 냉각시스템에서의 직접 냉각 방식과 간접 냉각 방식에 관한 연구)

  • Jang, Kyungmin;Kim, Kwangsun
    • Journal of the Semiconductor & Display Technology
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    • v.17 no.3
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    • pp.100-103
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    • 2018
  • Due to the plasma applied from the outside, which acts as an etchant during the etching process, considerable heat is transferred to the wafer and a separate cooling process is performed to effectively remove the heat after the process. In this case, a direct cooling method using a refrigerant is suitable for cooling through effective heat exchange. The direct cooling method using the refrigerant using the latent heat exchange is superior to the cooling method using the sensible heat exchange. Therefore, in this paper, AMESim is used to design a direct refrigerant cooling system using latent heat exchange simulator was built.The constructed simulator is reliable compared with the actual experimental results. It is expected that this simulator will help to design and search for optimal process conditions.

A Study on the Impact of IT and SCM Process Management Capability on e-SCM Performance (IT와 SCM 프로세스 관리역량이 e-SCM 성과에 미치는 영향에 관한 연구)

  • Lee, Sun-Ro;Kim, Ki-Young
    • Asia pacific journal of information systems
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    • v.17 no.3
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    • pp.79-103
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    • 2007
  • The main purpose of this study is to define antecedents that influence e-SCM synchronization and to investigate how it affects e-SCM performance. We, therefore, investigate (1) the impact of firms' internal IT planning capabilities on e-SCM synchronization and on SCM process management capability, (2) the impact of firms' internal IT infrastructure on e-SCM synchronization and on SCM process management capability, (3) the impact of firms' internal SCM process management capabilities on e-SCM synchronization, and finally (4) the impact of e-SCM synchronization on SCM performance. A survey has been administrated to the firms' SCM and marketing staffs and 171 returns analyzed. The results show that (1) IT plan has not direct impacts on e-SCM synchronization, but has direct impacts on organizational support, purchasing, and operations processes except logistics process. IT plan, however, has indirect impacts on e-SCM synchronization through purchasing and operations of SCM process management capability. (2) IT infrastructure has both direct and indirect effects on e-SCM synchronization, and also has direct impacts on organizational support, purchasing, and operations processes except logistics process. (3) SCM process management capabilities have direct impacts on e-SCM synchronization. Among these SCM core processes purchasing positively influences operations, which in turn positively influences logistics process management capability. (4) e-SCM synchronization has positive impacts on SCM performance indicator (SCOR), such as delivery reliability, responsiveness & flexibility, and cost. These results indicate that e-SCM synchronization can be critical to achieve better internal performance like cost and external performance like delivery reliability, responsiveness & flexibility of firms' SCM. In sum, this study demonstrates that the intervening role of e-SCM synchronization between e-SCM performance and IT management capability and between e-SCM performance and SCM core process management capability has been significant in achieving better e-SCM performance. Therefore, it can be suggested that e-SCM performance should be accomplished in consequence of the acceleration of e-SCM synchronization through the enhancement of preceding factors for the e-SCM synchronization.

Fabrication of Flexible OTFT Array with Printed Electrodes by using Microcontact and Direct Printing Processes

  • Jo, Jeong-Dai;Lee, Taik-Min;Kim, Dong-Soo;Kim, Kwang-Young;Esashi, Masayoshi;Lee, Eung-Sug
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08a
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    • pp.155-158
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    • 2007
  • Printed organic thin-film transistor(OTFT) to use as a switching device for an organic light emitting diode(OLED) were fabricated in the microcontact printing and direct printing processes at room temperature. The gate electrodes($5{\mu}m$, $10{\mu}m$, and $20{\mu}m$) of OTFT was fabricated using microcontact printing process, and source/drain electrodes ($W/L=500{\mu}m/5{\mu}m$, $500{\mu}m/10{\mu}m$, and $500{\mu}m/20{\mu}m$) was fabricated using direct printing process with hard poly(dimethylsiloxane)(h-PDMS) stamp. Printed OTFT with dielectric layer was formed using special coating system and organic semiconductor layer was ink-jet printing process. Microcontact printing and direct printing processes using h-PDMS stamp made it possible to fabricate printed OTFT with channel lengths down to $5{\mu}m$, and reduced the process by 20 steps compared with photolithography. As results of measuring he transfer characteristics and output characteristics of OTFT fabricated with the printing process, the field effect characteristic was verified.

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Fabrication of All-Solution Processed Transparent Silver Nanowire Electrode Using a Direct Printing Process

  • Baek, Jang-Mi;Lee, Rin;Seong, Myeong-Mo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.641-641
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    • 2013
  • We report the transparentsilver nanowire electrode fabricated by a direct printing process, liquid-bridge-mediated nanotransfer molding. We fabricated silver nanowire arrays by liquidbridge- mediated nanotransfer molding using the silver nanoparticle ink and PEDOT:PSS polymer. Weinvestigated the formation of silver nanowire arrays by SEM and transmittance of the transparent silver nanowire electrode. We also measured the conductivity to confirm the potential of our approach.

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Structure of Direct RF Sampling Receivers for GNSS Signals

  • Won, Yu-Jun;Ahn, Woo-Hyun;Lee, MinJoon;Park, Chansik;Seo, Bo-Seok
    • Journal of Positioning, Navigation, and Timing
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    • v.3 no.3
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    • pp.91-97
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    • 2014
  • A direct RF sampling method refers to a technique that directly converts a passband signal to an intermediate band or a baseband without using a mixer. This method is less complicated than an existing RF receiver because a mixer is not used. It uses digital processing after sampling, and thus can flexibly process signals in a number of bands using software. In this process, it is important to select an appropriate sampling frequency so that a number of signals can be converted to an intermediate band that is easy to process. In this study, going beyond previously studied direct RF sampling frequency selection methods, conditions that need to be additionally considered during receiver design were examined, and the structure of a direct RF sampling receiver that satisfies these conditions was suggested.

High-Performance Single-Crystal Organic Nanowire Field-Effect Transistors of Indolocarbazole Derivatives

  • Park, Gyeong-Seon;Jeong, Jin-Won;Seong, Myeong-Mo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.368-368
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    • 2012
  • We report solution-processed, high-performance single-crystal organic nanowire transistors fabricated from a novel indolocarbazole (IC) derivative. The direct printing process was utilized to generate single-crystal organic nanowire arrays enabling the simultaneous synthesis, alignment and patterning of nanowires using molecular ink solutions. Using this method, single-crystal organic nanowires can easily be synthesized by self-assembly and crystallization of organic molecules within the nanoscale channels of molds, and these nanowires can then be directly transferred to specific positions on substrates to generate nanowire arrays by a direct printing process. These new molecules are particularly suitable for p-channel organic field-effect transistors (OFETs) because of the high level of crystallinity usually found in IC derivatives. Selected area diffraction (SAED) and X-ray diffraction (XRD) experiments on these solution-processed nanowires showed high crystallinity. Transistors fabricated with these nanowires gave a hole mobility as high as 1.0 cm2V-1s-1 with nanowire arrays with the direct printing process.

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Characteristic Analysis and Selection of Process Parameters in Direct Rolling Processes (직접압연공정의 특성해석 및 공정변수 선정)

  • 박영준;조형석;이원호;강태욱
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1997.04a
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    • pp.384-388
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    • 1997
  • Recently,direct rolling process has been drawing increasing interests because production cost be greatly reduced by eliminating subsequent hot rolling processes. Such a process has been characterized to prosuce thin steel strip (thickness 1~5mm) directly from molten metal and to skip over the conventional hot rolling processes. However, since there are several process parameters, which affect the quality of product,and their relationship between the parametersare very complex,it is therefore very difficult to realize the process design and the quality control. To overcome these difficulties quantitative relationship between the parameters are investigated through a numerical analysis. Form these results, it is found that solidification final point is the most important paramter which is critical to quality of the strip. Also,the multiple regression model is obtianed to determine their relationship from the solidification final point and roll separating force which can be easily estimated

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A Coding Mode Image Characteristics-based Fast Direct Mode Decision Algorithm (코딩 모드 영상 특성기반의 고속 직접모드 결정 알고리즘)

  • Choi, Yung-Ho;Han, Soo-Hee;Kim, Lark-Kyo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.8
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    • pp.1199-1203
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    • 2012
  • H.264 adopted many compression tools to increase image data compression efficiency such as B frame bi-directional predictions, the direct mode coding and so on. Despite its high compression efficiency, H.264 can suffer from its long coding time due to the complicated tools of H.264. To realize a high performance H.264, several fast algorithms were proposed. One of them is adaptive fast direct mode decision algorithm using mode and Lagrangian cost prediction for B frame in H.264/AVC (MLP) algorithm which can determine the direct coding mode for macroblocks without a complex mode decision process. However, in this algorithm, macroblocks not satisfying the conditions of the MLP algorithm are required to process the complex mode decision calculation, yet suffering a long coding time. To overcome the problem, this paper proposes a fast direct mode prediction algorithm. Simulation results show that the proposed algorithm can determine the direct mode coding without a complex mode decision process for 42% more macroblocks and, this algorithm can reduce coding time by up to 23%, compared with Jin's algorithm. This enables to encode B frames fast with a less quality degradation.

A Study on Recoil Force Reduction Using a Low-recoil Direct Gun (저반동 전차포의 주퇴력 저감 연구)

  • Park, Jin-Saeng
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.15 no.5
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    • pp.125-130
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    • 2016
  • A low-recoil direct gun is useful in reducing the fire impulse generated by using a traditional shell. To apply a control equation to an AMESim Model, we have formulated a control equation for a recoil mechanism from the free object diagram. By modeling this equation, we have been able to compare the recoil distance and recoil force of a low-recoil direct gun. Here, we can analyze the recoil characteristics between traditional direct guns and low-recoil direct guns with perforated muzzle brakes. It is possible to mount a low-recoil direct gun with a perforated muzzle brake on a lightweight tracked vehicle by reducing its fire impulse.