• Title/Summary/Keyword: Open-gap

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An Experimental Study on Root-pass Welding of Open Gap by GMA Welding Process in Pipeline (GMA 용접공정을 이용한 오픈갭 수평고정관 초층 용접의 실험적 연구)

  • Kim, Ji-Sun;Kim, Ill-Soo;Park, Chang-Eun;Na, Hyun-Ho;Lee, Ji-Hye;Jung, Seong-Myeong
    • Journal of Welding and Joining
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    • v.29 no.3
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    • pp.64-69
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    • 2011
  • Since welding process for most pipelines with large diameter has been carried out by the manual process, automation of the welding process is necessary for the sake of consistent weld quality and improvement in productivity. Therefore the development of the optimized algorithm to decide the welding condition is an effective technique to prove the feasibility of interface standards and intelligent control technology to increase productivity and reduce the cost of system integration. In this study, the pipe welding experiment has been carried out using plused GMA welding process to select optimal welding condition. And necessary information in root-pass welding has been obtained by applying in the pipeline using the selected welding conditions through the welding experiment.

Endotracheal Intubation Using Submandibular Approach for Maxillofacial Trauma Patients: Report of 2 Cases

  • Youn, Gap-Hee;Ryu, Sun-Youl;Oh, Hee-Kyun;Park, Hong-Ju;Jung, Seunggon;Jeong, Seongtae;Kook, Min-Suk
    • Journal of The Korean Dental Society of Anesthesiology
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    • v.14 no.4
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    • pp.227-232
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    • 2014
  • The indication for submandibular intubation is the requirement for intraoperative maxillomandibular fixation (MMF) in the presence of injuries that preclude nasotracheal intubation. Thus, We reported 2 cased of endotracheal intubations via submandibular approach that is applicable in patients with skull base fractures for a reliable general anesthesia. Endotracheal intubation via submandibular approach was applied during general anesthetic procedures for open reduction in three patients with Le Fort II, III or nasoorbitoethmoid (NOE) fractures. No complications due to submandibular intubation, such as infection, postoperative scarring, nerve injury, hematoma, bleeding, or orocutaneous fistula, were observed following submandibular intubation. Endotracheal intubation via submandibular approach is effective in patients with skull base fractures. In our method, the tube connector is removed in orotracheal intubation in order to avoiding the tube removal or displacement. The advantages of this method are very simple, safe, and to provide the good operation field.

Heteroface p-$Al_{x}Ga_{1-x}As/p-GaAs/n-GaAs/n^{+}$-GaAs Solar Cell Grown by MOCVD (MOCVD를 이용한 Heteroface p-$Al_{x}Ga_{1-x}As/p-GaAs/n-GaAs/n^{+}$-GaAs 태양전지의 개발)

  • 창기근;임성규
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.28A no.1
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    • pp.30-39
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    • 1991
  • The influence of physical parameters (Al mole fraction, thickness, doping concentration) in the window and emitter on the efficiency characteristics of heteroface p-$Al_{x}Ga_{1-x}As/p-GaAs/n-GaAs/n^{+}$-GaAs solar cell is investigated. The maximum efficiency theoretically calculated in this device is obtained when a thickness of the window is in a range of (400-1000))$\AA$and a thickness/doping concentration of the emitter is in a range of (0.5-0.8)$\mu$m/(1-7)${\times}10^{17}cm^{-3}$, respectively. Also is the efficiency improved according to the increase of Al mole fraction in the indirect gap window(0.41${\le}x{\le}1.0$). The optimum designed heteroface cell with an area of 0.165cm$^2$fabricated using MOCVD exhibits an active area conversion efficiency of 17%, having a short circuit current density of 21.2mA/cm\ulcorner an open circuit voltage of 0.94V, and a fill factor of 0.75 under ELH-100mW/cm$^2$illumination.

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Applying In-Page Logging to SQLite DBMS (SQLite DBMS에 IPL 기법 응용)

  • Na, Gap-Joo;Kim, Sang-Woo;Kim, Jae-Myung;Lee, Sang-Won
    • Journal of KIISE:Databases
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    • v.35 no.5
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    • pp.400-410
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    • 2008
  • Flash memory has been widely used in mobile devices, such as mobile phone and digital camera. Recently flash SSD(Solid State Disk), having same interface of the disk drive, is replacing the hard disk of some laptop computers. However, flash memory still cannot be considered as the storage of database systems. The FTL(Flash Translation Layer) of commercial flash SSD, making flash memory operate exactly same as a hard disk, shows poor performance on the workload of databases with many random overwrites. Recently In-Page Logging(IPL) approach was proposed to solve this problem. In this paper, we implement IPL approach on SQLite, a popular open source embedded DBMS, and evaluate its performance. It improves the performance by up to 30 factors for update queries.

Document Summarization using Pseudo Relevance Feedback and Term Weighting (의사연관피드백과 용어 가중치에 의한 문서요약)

  • Kim, Chul-Won;Park, Sun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.3
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    • pp.533-540
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    • 2012
  • In this paper, we propose a document summarization method using the pseudo relevance feedback and the term weighting based on semantic features. The proposed method can minimize the user intervention to use the pseudo relevance feedback. It also can improve the quality of document summaries because the inherent semantic of the sentence set are well reflected by term weighting derived from semantic feature. In addition, it uses the semantic feature of term weighting and the expanded query to reduce the semantic gap between the user's requirement and the result of proposed method. The experimental results demonstrate that the proposed method achieves better performant than other methods without term weighting.

BIM and Thermographic Sensing: Reflecting the As-is Building Condition in Energy Analysis

  • Ham, Youngjib;Golparvar-Fard, Mani
    • Journal of Construction Engineering and Project Management
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    • v.5 no.4
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    • pp.16-22
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    • 2015
  • This paper presents an automated computer vision-based system to update BIM data by leveraging multi-modal visual data collected from existing buildings under inspection. Currently, visual inspections are conducted for building envelopes or mechanical systems, and auditors analyze energy-related contextual information to examine if their performance is maintained as expected by the design. By translating 3D surface thermal profiles into energy performance metrics such as actual R-values at point-level and by mapping such properties to the associated BIM elements using XML Document Object Model (DOM), the proposed method shortens the energy performance modeling gap between the architectural information in the as-designed BIM and the as-is building condition, which improve the reliability of building energy analysis. Several case studies were conducted to experimentally evaluate their impact on BIM-based energy analysis to calculate energy load. The experimental results on existing buildings show that (1) the point-level thermography-based thermal resistance measurement can be automatically matched with the associated BIM elements; and (2) their corresponding thermal properties are automatically updated in gbXML schema. This paper provides practitioners with insight to uncover the fundamentals of how multi-modal visual data can be used to improve the accuracy of building energy modeling for retrofit analysis. Open research challenges and lessons learned from real-world case studies are discussed in detail.

Accurate Measurements of the Unloaded Q of a Dielectric-loaded High-Q $TE_{01{\delta}}$ mode Cavity Resonator with HTS Endplates

  • Kwon, H.J.;Hur, Jung;Lee, Sang-Young
    • Progress in Superconductivity
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    • v.1 no.1
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    • pp.36-41
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    • 1999
  • Methods for mode identification and accurate measurements of the unloaded Q ($Q_0$) of a dielectric-loaded $TE_{01{\delta}}$ mode cavity resonator with HTS endplates are proposed. A resonator with a sapphire rod and $YBa_2Cu_3O_{7-x}$(YBCO) endplates was prepared and its microwave properties were studied at temperatures above 30 K. The $TE_{01{\delta}}$ mode $Q_0$ of the resonator, designed to work as a tunable resonator with variations in the gap distance (s) between the sapphire rod and the top YBCO, was more than 1000000 at s = 0 mm and at 30 K with the resonant frequency of 19.56 GHz. The $TE_{01{\delta}}$ mode $Q_0$ decreases as s increases for s < 2 mm until mode couplings between the $TE_{01{\delta}}$ mode and other modes appeared at s = 2 mm. Significant dependence of the $TE_{01{\delta}}$ mode $Q_0$ on the input and output coupling constants was also observed. Applications of the open-ended $TE_{01{\delta}}$ mode cavity resonator for a tunable resonator with a very high Q as well as a characterization tool for the surface resistance measurements of HTS films are described.

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Extracting Method of External Quality Factor(Qe) Using Phase Response (위상특성을 이용한 공진기의 외적 양호도(Qe) 추출 방법)

  • Park, Young-Bae;Kim, Gi-Rae
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.10
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    • pp.2065-2071
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    • 2011
  • The external quality factor ($Q_e$) is controlled by coupling condition between resonator and input/output ports in design of microwave filter. In this paper, we represent extracting method of external quality factor using phase response for resonator with input/output ports according to position of feed line from microstrip line resonator. The results regarding to position, coupling gap and line width for tapped line and coupled line structure are represented, and we got the exact $Q_e$ value from the this method. This results will be applied to coupled resonator filter design.

A Comparative Study on Function and Performance of Snort and Suricata (Snort와 Suricata의 탐지 기능과 성능에 대한 비교 연구)

  • Jeong, Myeong Ki;Ahn, Seongjin;Park, Won Hyung
    • Convergence Security Journal
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    • v.14 no.5
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    • pp.3-8
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    • 2014
  • We have tried to compare two different IDSs which are widespread over the network administrator, Snort and Suricata, in functional and performance aspects. Specifically, we focused on analyzing upon what functions for detecting threat were added newly and what Multi-Threading introduced newly for Suricata has influenced in a performance aspect. As a result, we could discover that there are some features in Suricata which has never existed in Snort such as Protocol Identification, HTTP Normalizer & Parser, and File Identification. Also, It was proved that the gap of PPS(Packets Per Second) becomes wider, as the number of CPU Cores which are working increase. Therefore, we could conclude that Suricata can be an efficient alternative for Snort considering the result that Suricata is more effective quantitatively as well as qualitatively.

Experimental Study on the the Maglev Train Guideway Girder : Composite System with PSC-U Type Girder and Precast Deck (자기부상열차 가이드웨이 거더의 실험적 연구: PSC-U 형 거더와 프리캐스트 바닥판의 합성 시스템)

  • Jin, Byeong-Moo;Kim, In-Gyu;Kim, Young-Jin;Yeo, In-Ho;Chung, Won-Seok
    • Proceedings of the KSR Conference
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    • 2008.06a
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    • pp.46-55
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    • 2008
  • Maglev is a system that a train runs levitated above a rail. Therefore it is very important to maintain a constant levitation gap for achieving serviceability and ride comfort. This study is a cooperation research subject of the 3-1 subject, performance improvement of maglev track structures, of the Center for Urban Maglev Program in Korea, started in 2006. The aim of this study is development of rapid constructions of bridge superstructure for maglev. At present, precast deck is widely used because of its superiority to cast-in-place concrete on quality and the term of works. The research group suggested basic systems of maglev guideway with PSC-U type and trapezoidal open steel box type girder, and precast deck, cooperating with Korea Railroad Research Institute, the managing institute of the 3-1 subject. In this study, longitudinally full-scale guideway girder system was fabricated and static/dynamic test of the girder was performed for the purpose of the performance evaluation.

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