• Title/Summary/Keyword: Dual Units

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A Study on Quality Improvement of Electrical Master Box for KUH (한국형 기동헬기 전원분배 제어장치의 품질 향상에 관한 연구)

  • Kim, Young Mok;Jun, Byung Kyu;Jeong, Sang Gyu;Lee, Joo Hyung
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.45 no.1
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    • pp.71-78
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    • 2017
  • The electrical power system of Korean Utility Helicopter(KUH) is designed as a dual control system to enhance the system safety of aircraft and each system is installed separately at left and right of the aircraft. The system is composed of 2 AC generators, 1 APU generator, 2 Transformer Rectifier Units(TRU), AC/DC Electrical Master Box(AC/DC EMB). The AC/DC EMB, consists of 2 AC EMB and 2 DC EMB, is essential equipment which supply and distribute electric power to the aviation electronics and electrical equipment of KUH. There were defects caused by internal short circuit in AC EMB during the first production phase of the KUH. This paper describes the analysis of the defects, troubleshooting process, root cause, and the solution by design change.

Potential Explosion Risk Comparison between SMR and DMR Liquefaction Processes at Conceptual Design Stage of FLNG (FLNG개념설계 단계에서 SMR 및 DMR 액화공정의 잠재적 폭발위험도 비교)

  • You, Wonwo;Chae, Minho;Park, Jaeuk;Lim, Youngsub
    • Journal of Ocean Engineering and Technology
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    • v.32 no.2
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    • pp.95-105
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    • 2018
  • An FLNG (floating liquefied natural gas) or LNG FPSO (floating production, storage and offloading) unit is a notable offshore unit with the increasing demand for LNG. The liquefaction process on an FLNG unit is the most important process because it determines the economic feasibility, but would be a hazard source because of the large quantity of hydrocarbons. While a high efficiency process such as C3MR has been preferred for onshore liquefaction processes, a relatively simple process such as the SMR (single mixed refrigerant) or DMR (dual mixed refrigerant) liquefaction process has been selected for offshore units because they require a more compact size, lighter weight, and higher safety due to their space limitation for facilities and long distance from shore. It is known that an SMR has the advantages of a simple configuration, small footprint, and lower risk. However, with an increased production rate, the inherent safety of SMR needs to be evaluated because of its small train capacity. In this study, the potential explosion risks of the SMR and DMR liquefaction processes were evaluated at the conceptual design stage. The results showed that an SMR has a lower overpressure than a DMR at the same frequency, only with a small production capacity of 0.9 MTPA. With increased capacity, the overpressure of the SMR was higher than that of the DMR. The increased number of trains increased the frequency in spite of the small amount of equipment per train. This showed that the inherent risk of an SMR is not always lower than that of a DMR, and an additional risk management strategy is recommended when an SMR is selected as the concept for an FLNG liquefaction process compared to the DMR liquefaction process.

Construction and Characterization of Transformed Insect Cells Expressing Baculovirus Very Late Factor in an Infection-Independent Manner

  • Park, Hye-Jin;Lee, Kwang-Sik;Cho, Eun-Sook;Yun, Eun-Young;Kang, Seok-Woo;Kim, Keun-Young;Sohn, Hung-Dae;Jin, Byung-Rae
    • International Journal of Industrial Entomology and Biomaterials
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    • v.2 no.1
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    • pp.19-26
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    • 2001
  • Transformed Spodoptera frugiperda (Sf9) cells expressing baculovirus very late factor (VLF-1) were constructed by using Autograha nuclear polyhedrosis virus (AcNPV) immediate earthy gene (ie1). Neomycin-resistance gene as a selectable marker was introduced under the control of AcNPV ie1 promoter, and Bombyx mori nuclear polyhedrosis (BmNPV-K1) vlf-1 gene was introduced under the control of the Drosophila heat shock protein gene (hspr70) promoter to yield dual expression plasmid with two independent transcription units. It was transfected into Sf9 cells and cell clones expressing vlf-1 were selected by G4l8 treatment. Genomic DNA from transformed cells was isolated and integration of AcNPV iel harboring vlf-1 was confirmed by PCR using AcNPV iel-specific primers and Southern blot analysis. The transformed cells expressing VLF-1 in an infection-independent manner expressed foreign gene product of recombinant baculovirus in the earlier stage of infection compared with control Sf9 cells. These results suggest the possible to develop highly efficient transformed insect cells for baculovirus expression vector system.

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DESIGN OF A SINGLE MODE VARIABLE BRIDGE TYPE SPLIT-POWERED CVT WITH AN INNER-SPHERICAL CONTINUOUSLY VARIABLE UNIT

  • Seong, S.H.;Lee, H.W.;Choi, J.H.;Park, N.G.
    • International Journal of Automotive Technology
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    • v.8 no.6
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    • pp.799-806
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    • 2007
  • One method for improving the torque capacity of the CVT is to use a split-powered CVT(SPCVT) to reduce the power transmitted into a continuously variable unit(CVU). A variable bridge SPCVT with two planetary gear units(PGUs), which are composed of a sun gear, a ring gear, and carrier and planetary gears, can minimize the power to the CVU. However, a SPCVT with a conventional CVT should possess a dual mode, which would allow the conventional CVT to be used at high speeds and an additional gear train to be used at low speeds. The inner-spherical CVU(ISCVU) with an inner and outer spherical contact mechanism developed in this study can cover the range from low to high speeds. The rated power and the overall speed ratios were 100 kW and $0.09{\sim}0.36$, respectively. Power efficiency was numerically calculated to be over 90% over the speed ratio range of $0.1{\sim}0.29$. The maximum shear stress at the two contact areas of the rotor pairs, the minimum life and the overall size were estimated to be 700 MPa, 276 kh and $350{\times}350{\times}400mm^3$, respectively. This study shows that an ISCVU and a variable bridge type PGU can realize the SPCVT with a single mode for a vehicle.

A Study on the Comparison and Characteristics of Public Standard Housing Unit Plan before and after the Independence from the Japan Occupation (광복전후(光復前後) 공영주택(公營住宅)의 평면비교(平面比較)와 변화특성(變化特性)에 관한 연구(硏究))

  • Yoo, Jae-Woo
    • Journal of architectural history
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    • v.11 no.2 s.30
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    • pp.23-35
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    • 2002
  • Even though there have been greate changes in the types and contents of the housing plan in Korea since the Modem age, it seems that the identity of traditional dwelling culture is still remains within it. The purpose of this study is to examine the characteristics and features in the development of the 'Public Standard' Housing Unit Plan by comparing the differences and similarities in unit plans in housings built on Japanese occupation period and those built after the period. From the study, we can conclude as follows: 1. The public standard housing unit plans on both periods have shown the common features in the composition of their physical forms in the way that the front-row area still remains the traditional housing culture and the rear-row area reflects the desires of the modem lives. The structure of the dual-row unit plan appeared in the public standard housing plan was caused by the cultural acculturation in Japanese occupation period. 2. The public standard housing unit plans, however, show the differences in the contents and meaning in units plans with the them of the Japanese housing because of the cultural differences. These differences took placed autonomously through the change of housing plans in the modern time, and have the common features such that 1) the changes in the Maru-centered plan type differ in composition from the inner-corridor plan type used Japanese housing, and 2) the composition of the open-inner spaces in the double-row housing plan reflects the single-row outer open space In the traditional housing. All of these cultural progresses in the public standard housing unit plans was took place as the result of the inner-oriented and notional circulations derived from the modernity. However, the transformed unit plans still contains the identity derived from the variation of the traditional Korean building elements such as Maru and Ondol. In other words, those are the Maru-centered and composed housing plans with juxtaposition of the inner block and the outer block. As the conclusion, though the public standard dwelling unit plan has the similarity in the physical form, it is different in the cultural Identity and meaning from the public standard plans before the independence from the Japan occupation.

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DEVELOPMENT OF 230 GHZ RADIO RECEIVER SYSTEM FOR SRAO

  • Lee, Jung-Won;Kim, Chang-Hee;Kang, Hyunwoo;Lee, Bangwon;Han, Junghwan;Lee, Seok-Ho;Jeong, Il-Gyo;Koo, Bon-Chul;Park, Yong-Sun
    • Journal of The Korean Astronomical Society
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    • v.46 no.6
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    • pp.225-234
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    • 2013
  • We develop a radio receiver system operating at ${\lambda}{\sim}1.3$ mm for the 6 m telescope of Seoul Radio Astronomy Observatory. It consists of a dual polarization receiver, a couple of IF processing units, two FFT spectrometers, and associated software. By adopting sideband-separating superconductor mixers with image band terminated to waveguide load at 4.2 K, we achieve $T_{RX}{\leq}100$ K and $T_{sys}$ less than 150 K at best weather condition over 210-250 GHz frequency range. The intermediate frequency signal of 3.5-4.5 GHz is down converted to 0-1 GHz and fed into the FFT spectrometers. The spectrometer covers 1 GHz bandwidth with a spectral resolution of 61 KHz. Test observations are conducted toward several radio sources to evaluate the performance of the system. Aperture and beam efficiencies measured by observing planets are found to be typically 44 ~ 59% and 47 ~ 61%, respectively over the RF band, which are consistent with those measured at 3 mm band previously.

Real-time Implementation or AMR-WB Speech Coder Using TMS320C5509 DSP (TMS320C5509 DSP를 이용한 AMR-WB 음성부호화기의 실시간 구현)

  • Choi Song-ln;Jee Deock-Gu
    • The Journal of the Acoustical Society of Korea
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    • v.24 no.1
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    • pp.52-57
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    • 2005
  • The adaptive multirate wideband (AMR-WB) speech coder has an extended audio bandwidth from 50 Hz to 7 kBz and operates on nine speech coding bit-rates from 6.6 to 23.85 kbit/s. In this Paper, we present the real-time implementation of AMR-WB speech coder using 16bit fixed-point TMS320C5509 that has dual MAC units. Firstly, We implemented AMR-WB speech coder in C 1anguage level using intrinsics, and then performed optimization in assembly language. The computational complexity of the implemented AMR-WB coder at 23.85 kbit/s is 42.9 Mclocks. And this coder needs the program memory of 15.1 kwords, data ROM of 9.2 kwords and data RAM of 13.9 kwords.

Contents Analysis of Figure Skating Costume Design (피겨스케이팅 의상디자인의 내용분석연구)

  • Jang, A-Reum;Lee, Myoung-Hee
    • Journal of the Korean Society of Clothing and Textiles
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    • v.35 no.2
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    • pp.146-155
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    • 2011
  • This study examines the design characteristics of figure skating costumes by a content analysis of their design elements. The content analysis method for the study was used based on 185 photos of female figure skaters. A total of 218 coding units in 15 categories were used. In the category of color, unicolor costumes were the mainstay and represented 48.11% of the total costumes. Black costumes showed the highest rate (13.51%), followed by red (7.57%) and blue (7.03%). In the dual-color costumes, combinations of red and black and white and black, represented 4.32% of all costumes. A camisole was the most popular type of neckline (20.54%). Stand collars with neck decorations were found in 5.95% of the costumes. In addition, 98.2% of all figure skating costumes had decorations (crystal beads 21.86% were the most frequently used decoration type), 65.41% exposed all the shoulders and arms, 70.81% of the costumes did not have sleeves, 5.41% of the costumes had arm decorations, and 3.78% had wrist decorations. In the analysis of the hem of skirts, 32.40% had a curved line, 30.73% had a straight line, and 15.08% had an unrecognizable form. In general, the figure skating costumes have stand collars with neck decorations, arm and wrist decorations, and irregular skirt hems that are not found in everyday dresses. To emphasize and intensify a theatrical effect, the costumes were fabulously decorated with spangles, crystal beads, feathers, and lace; black, red, and blue were frequently used. The skirts had frills, fringe, flared lines, and beads on them to reflect the stage lights and emphasize movements.

The Effects of Brand Evidence on the Switching barrier and Relational Performance in the Hotel Firms (호텔기업의 브랜드 증거가 전환장벽과 관계성과에 미치는 영향)

  • Lee, Moou-Houng
    • Culinary science and hospitality research
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    • v.17 no.5
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    • pp.139-153
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    • 2011
  • The study is a hotel firm's brand evidence on the switching and relational performance by identifying a causal relationship to the differentiated and competitive was to provide useful information. Units of samples for evidence of brand switching hotels in Seoul participated in surveys customers in 2011, from June 10 to 20 July 2011 for a total of 500 copies for distribution and the Department of dual 408 with SPSS 18.0 and AMOS 18.0 Using factor analysis and reliability verification carried out, and presented research in order to test the hypothesis covariance structure analysis was performed. Analysis, employee services switching barriers and switching costs showed no significant affect. Switching barriers and switching costs, brand name, image congruence transition castle wall and switching costs, alternative attractiveness showed no significant visible results. And perceived price on switching barriers to conversion rates showed was significant affect. Second, switching barriers, switching costs, alternative attractiveness and that the relationship, to help conversion of non-financial performance showed no significant affect. Third, the practitioner services, brand names, images, match the castle there, and non-financial performance of the transition showing a statistically significant result was found.

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The Rhetoric of Revelation and the Politics of Prophecy: A Reading of Ginsberg's "Howl" and "Kaddish" (계시의 수사와 정치학-긴즈버그의 「울부짖음」과 「캐디쉬」를 중심으로)

  • Son, Hyesook
    • Journal of English Language & Literature
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    • v.57 no.4
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    • pp.529-552
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    • 2011
  • My essay aims at reading Ginsberg's "Howl" and "Kaddish" with the concept of 'shaman-prophet-poet' to illustrate the dynamic relationship between his poetics and radical politics. Throughout his widely-ranging career, Ginsberg represents himself as a poet-prophet and commands a typical rhetoric of revelation as a way of decentering Cold War orthodoxies. While well aware of the oppressive and pervasive power of the dominant post-war ideologies, he adopts 'madness' to oppose conventional political, social, and religious institutions; by way of entering into the madness of this world and actively engaging himself as a victim, he can finally heal both himself and the world. This dual function of poet characterizes his rhetoric of revelation, but it doesn't appeal to the mainstream of American critical ideology where the post-structural approach to language and subject gives a skeptical look at any account of active human agency and humanistic belief in the possibility of language. In "Howl" and "Kaddish," Ginsburg persuades the reader of the truth of his own vision through the convincing and realistic portraits of his contemporaries as well as his own mother and family. Different from his visionary predecessors such as Emerson and Whitman, Ginsberg knew the difficulty of a negotiation between history and divine vision, and attempted to imbricate his family, friends, and even the larger social and political units within his visionary experience in order to avoid naive idealism, escapism, or solipsism. Furthermore, he deconstructs the Logos of Western prophecy and replaces it with the groundless identity and the nontheistic epistemology of Buddhism, which, in turn, leads to emptying his powerful language of absolutist meaning and prevents his prophecy from becoming re-reified as divine essentialism. Ginsberg's idea of poet and poem revitalizes the skeptical view on language and literary representation of our contemporary critical community which is unwilling to engage the experimental scope of his radical prophecy.