• Title/Summary/Keyword: Novel Process

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Novel process of rare-earth free magnet and thermochemical route for the fabrication of permanent magnet

  • Choi, Chul-Jin
    • Proceedings of the Korean Magnestics Society Conference
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    • 2013.12a
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    • pp.89-89
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    • 2013
  • Rare earth (RE) - transition metal based high energy density magnets are of immense significance in various engineering applications. $Nd_2Fe_{14}B$ magnets possess the highest energy product and are widely used in whole industries. Simultaneously, composite alloys that are cheap, cost effective and strong commercially available have drawn great attention, because rare-earth metals are costly, less abundant and strategic shortage. We designed rare-earth free alloys and fabrication process and developed novel route to prepare $Nd_2Fe_{14}B$ powders by wet process employing spray drying and reduction-diffusion (R-D) without the use of high purity metals as raw material. MnAl-base permanent magnetic powders are potentially important material for rare-earth free magnets. We have prepared the nano-sized MnAl powders by plasma arc discharge and micron-sized MnAl powders by gas atomization. They showed good magnetic property, compared with that from conventional processes. $Nd_2Fe_{14}B$ powders with high coercivity of more than 10 kOe were successfully synthesized by adjusting R-D step, followed by precise washing system. It is considered that this process can be applied for the recycling of RE-elements extracted from ewaste including motors.

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A Two-Step Screening Algorithm to Solve Linear Error Equations for Blind Identification of Block Codes Based on Binary Galois Field

  • Liu, Qian;Zhang, Hao;Yu, Peidong;Wang, Gang;Qiu, Zhaoyang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.9
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    • pp.3458-3481
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    • 2021
  • Existing methods for blind identification of linear block codes without a candidate set are mainly built on the Gauss elimination process. However, the fault tolerance will fall short when the intercepted bit error rate (BER) is too high. To address this issue, we apply the reverse algebra approach and propose a novel "two-step-screening" algorithm by solving the linear error equations on the binary Galois field, or GF(2). In the first step, a recursive matrix partition is implemented to solve the system linear error equations where the coefficient matrix is constructed by the full codewords which come from the intercepted noisy bitstream. This process is repeated to derive all those possible parity-checks. In the second step, a check matrix constructed by the intercepted codewords is applied to find the correct parity-checks out of all possible parity-checks solutions. This novel "two-step-screening" algorithm can be used in different codes like Hamming codes, BCH codes, LDPC codes, and quasi-cyclic LDPC codes. The simulation results have shown that it can highly improve the fault tolerance ability compared to the existing Gauss elimination process-based algorithms.

Low Noise and High Linearity GaAs LNA MMIC with Novel Active Bias Circuit for LTE Applications

  • Ryu, Keun-Kwan;Kim, Yong-Hwan;Kim, Sung-Chan
    • Journal of information and communication convergence engineering
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    • v.15 no.2
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    • pp.112-116
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    • 2017
  • In this work, we demonstrated a low noise and high linearity low noise amplifier (LNA) monolithic microwave integrated circuit (MMIC) with novel active bias circuit for LTE applications. The device technology used in this work relies on a process involving a $0.25-{\mu}m$ GaAs pseudomorphic high electron mobility transistor (PHEMT). The LNA MMIC with a novel active bias circuit has a small signal gain of $19.7{\pm}1.5dB$ and output third order intercept point (OIP3) of 38-39 dBm in the frequency range 1.75-2.65 GHz. The noise figure (NF) is less than 0.58 dB over the full bandwidth. Compared with the characteristics of the LNA MMIC without using the novel active bias circuit, the OIP3 is improved about 2-3 dBm. The small signal gain and NF showed no significant change after using the active bias circuit. The novel active bias circuit indeed improves the linearity performance of the LNA MMIC without degradation.

Is "Southern Literature" Alive?: Machine Dream's Incomplete Memories and Their Materiality (미국'남부문학'은 현존하는가?-『머쉰 드림』에 나타난 미완성의 기억과 기억의 물질성)

  • Yu, Jeboon
    • Journal of English Language & Literature
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    • v.59 no.4
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    • pp.545-567
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    • 2013
  • Keeping in mind the hybridity and plurality of Southern Literature, this paper discusses the traits of Southern literature in Jayne Ann Phillips's first novel, Machine Dream. The novel's frequent use of memory and oral reconstruction of a family history accompanied by the feeling of loss in the process of depicting the South's past typically signifies "The Southern" which reminds us of the works of William Faulkner, Katherine Ann Porter, and Eudora Welty. Nevertheless, Phillips's South is more fragmented and her narrative is more evasive and varied than any of her Southern predecessors. The South of the twentieth century from the period of Depression until 1972 is reconstructed differently depending on memories and desires of the four members of Hampson family in this novel, either as a place of nostalgia or as the place of trauma or as the place to survive only in memory. The oxymoronic title of the novel, "machine dreams" signifies that dream and memory of the South cannot remain independent in its epistemological entity but exist as a mixture of materiality of every day life in the modern South. The hybridity of this dream and of the South is what defines itself as Southern. Yet Phillips retains feeling of loss and lament enough to create a modern Southern novel rooted in Southern Literature. Thus, the title itself works an antinomic signifier of both the presence and absence of the dream of the South and of Southern Literature.

A Study on the Realism of Graphic Novel : Focused on Pascal Croci's (리얼리즘적 그래픽 노블: 파스칼 크로시의 『세슘137』)

  • Park, Yoo Shin
    • Cartoon and Animation Studies
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    • s.32
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    • pp.121-140
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    • 2013
  • This study takes a look at diverse artistic strategies is taking as a graphic novel of participation. Pascal Croci has used and combined the forms to convey the message he want as a writer of an inclusive graphic novel, image-text. It is linked with an intrinsic to the graphic novel as well as tradition of realism in a wide variety of genres. This study takes a brief look at the realism art in each genre and confirms in relation to the artistic characteristics of intrinsic to the graphic novel is taking as a graphic novel of participation. is consists of the process of covering a case and the form of a broadcasting report and a fictional format emphasizes the objectivity in contents to highlight the journalistic characteristics of the general narrative. uses various artistic languages of realism. The audience feels a realistic case through the experience and writer's message is convey effectively. shows the generic openness of the graphic novel.

Performance Analysis and the Novel Optical Decoder Scheme for Optical CDMA System (광 CDMA를 위한 새로운 광복호기 설계와 성능분석)

  • 강태구;윤영설;최영완
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.7C
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    • pp.712-722
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    • 2002
  • We have investigated a novel optical decoder for a fiber-optic code division multiple access(CDMA) communication systems. The conventional optical encoder and decoder have the advantage of simple structure. However the number of users in the system is limited by the auto- and cross-correlation properties generated in decoding process. In previous studies, to improve the system performance, although they used an optical code that minimize the sidelobe and cross-correlation, could not yet find a novel methods for performance improvement in fiber-optic CDMA system. Thus, it is necessary to investigate the novel optical decode in order to improve the performance of system. In this paper, we schematize the AND gate logic element(AGLE) composed with 1$\times$2 or 1$\times$3 coupler and the optical thyristor and propose the novel optical decoder using K(weight) AGLE. The optical thyristor only passes the overlapped signal and clips other signals. Such a novel concept means that the optical thyristor can operate as a hard-limiter. We analyze the fiber-optic CDMA system using the novel optical decoder with simulation and is found that the novel optical decoder using the AGLE and optical thyristor excludes the sidelobe and cross-correlation intensity between any two sequences.

THE NOVEL SILICON MEMS PACKAGE FOR MMICs (초고주파 집적 회로를 위한 새로운 실리콘 MEMS 패키지)

  • 권영수;이해영;박재영;부종욱
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2000.11a
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    • pp.104-108
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    • 2000
  • In this paper, we characterized a novel MEMS package using high resistivity silicon for microwave and millimeter-wave devices. The manufactured MEMS package shows -20dB of S$\sub$11/ and -0.4dB of S$\sub$21/ up to 200GHz. The new package can be a low cost and high performance solution due to process compatibility with on-chip devices and very small and precise dimensions by semiconduotor technology.

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An evolving integrative physiology: skeleton and energy metabolism

  • Lee, Na-Kyung
    • BMB Reports
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    • v.43 no.9
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    • pp.579-583
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    • 2010
  • The adipocyte-derived hormone leptin regulates appetite and bone mass. Recent research demonstrates that reciprocally, osteoblasts have a role in controlling energy metabolism. Several genes expressed in osteoblasts are involved in this process, and one of them is the Esp gene. The remaining genes regulate Esp gene expression. OST-PTP, the protein name of Esp, regulates the carboxylation of osteocalcin secreted from osteoblasts, thus affecting insulin sensitivity and insulin secretion. This review provides evidence for a novel interpretation of the connection between bone and energy metabolism and expands our understanding of the novel physiology of bone beyond its classical functions.

Synthesis of Novel Carboacyclic Nucleosides with Vinyl Bromide Moiety as Open-chain Analogues of Neplanocin A

  • Choi, Myung-Hee;Kim, Hee-Doo
    • Archives of Pharmacal Research
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    • v.26 no.12
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    • pp.990-996
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    • 2003
  • A novel carboacyclic nucleoside analogue, 9-[2-bromo-4-hydroxy-3-hydroxymethyl-2-butenyl] adenine, and its derivatives were designed and synthesized as open-chain analogues of neplanocin A. The syntheses were accomplished via the coupling of adenine or pyrimidine bases to the key intermediate allylic bromide 7. The bromide 7 was prepared from epichlorohydrin in a seven step process in a 54% overall yield. The synthesized compounds were evaluated for their antiviral activity against the polio virus, HSV and HIV.

A novel optical cell compressor for optical time division multiplexing system

  • 신서용;추광욱;원용협
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.3
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    • pp.524-531
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    • 1997
  • A novel optical cell compressor for optical time division multiplexing system is presented. The compressor is capable of generating optically compressed very high bit-rate (possibly several tens of Gb/s) signals with minimum hardware. Contrast to the previously reported optical compressor, the compressor is mainly composed of passive optical devices and requires no synchronization among control signals in the process of compression, which results in simple implementation. We demonstrate a generation of optically compressed 6 Gb/s optical cells to confirm the fundamental operation of the compressor.

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