• Title/Summary/Keyword: Full-envelope

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Deformation characteristics of brick masonry due to partial unloading

  • Alshebani, Milad M.;Sinha, S.N.
    • Structural Engineering and Mechanics
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    • v.11 no.5
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    • pp.565-574
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    • 2001
  • Experimental investigation into the behaviour of half-scale brick masonry panels were conducted under cyclic loading normal to the bed joint and parallel to the bed joint. For each cycle, full reloading was performed with the cycle peaks coinciding approximately with the envelope curve. Unloading, however, was carried out fully to zero stress level and partially to two different stress levels of 25 percent and 50 percent of peak stress. Stability point limit exhibits a unique stress-strain curve for full unloading but it could not be established for partial unloading. Common point limit was established for all unloading-reloading patterns considered, but its location depends on the stress level at which unloading is carried to. Common point curves were found to follow an exponential formula, while residual strains versus envelope strains can be expressed by a polynomial function of a single term. The relation between residual strain and envelope strain can be used to determine the stress level at which deterioration due to cyclic loading began.

A Study on the Kinematic Envelope of the Railway Vehicle (철도차량의 Kinematic Envelope에 관한 연구)

  • 양희주;이강운;박길배
    • Proceedings of the KSR Conference
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    • 2002.10b
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    • pp.863-869
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    • 2002
  • Studied in this paper was the kinematic envelope of the railway vehicle to calculate the lateral displacement using the multi-body dynamic simulation program (VAMPIRE) and the BASS 501. The lateral displacement of railway vehicle is occurred by the clearance between wheel flange and rail, the track irregularity, the property of each suspension of vehicle and the cant of track etc. The results of analysis shown that Vehicle is not interfere with subway platform in any conditions namely the tare and full load condition, the wheel wear condition and the stationary and running of vehicle.

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Full-Envelope Controller Switching Scheme Using Bumpless Transfer Implementation Algorithm (무충돌 전환 구현 알고리즘을 사용한 전비행영역 제어기 교체법)

  • Kim, Tae-Shin;Kwon, Oh-Kyu
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.36 no.6
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    • pp.574-580
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    • 2008
  • This paper has proposed a controller switching scheme for full-envelope aircraft control using the bumpless transfer implementation algorithm developed recently. This switching scheme has combined by proper rules the common existing method which switches the controller according to attitude and mach number of the aircraft with an optimization method which uses the cost function relating to bump phenomenon by means of controller switching criterion. This paper exemplifies the control performance improvement via simulations applied to a high performance aircraft benchmark problem in a wide operating range to test the proposed controller switching scheme.

Binary Power Amplifier with 2-Bit Sigma-Delta Modulation Method for EER Transmitter

  • Lim, Ji-Youn;Cheon, Sang-Hoon;Kim, Kyeong-Hak;Hong, Song-Cheol;Kim, Dong-Wook
    • ETRI Journal
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    • v.30 no.3
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    • pp.377-382
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    • 2008
  • A novel power amplifier for a polar transmitter is proposed to achieve better spectral performance for a wideband envelope signal. In the proposed scheme, 2-bit sigma-delta (${\Sigma}{\Delta}$) modulation of the envelope signal is introduced, and the power amplifier configuration is modified in a binary form to accommodate the 2-bit digitized envelope signals. The 2-bit ${\Sigma}{\Delta}$ modulator lowers the noise of the envelope signal by fine quantization and thus enhances the spectral property of the RF signal. The Ptolemy simulation results of the proposed structure show that the spectral noise is reduced by 10 dB in a full transmit band of the EDGE system. The dynamic range is also enhanced. Since the performance is improved without increasing the over-sampling ratio, this technique is best suited for wireless communication with high data rates.

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Ultrastructure of the External Egg Envelopes in Two Cobitid Fishes (Cobitidae) (미꾸리과 어류 2종에 대한 난막의 미세구조)

  • Park, Jong-Young;Kim, Ik-Soo
    • Korean Journal of Ichthyology
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    • v.13 no.1
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    • pp.19-23
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    • 2001
  • The full-grown oocyte envelope of the two spined loaches, Niwaella multifasciata and Kichulchoia brevifasciata, was examined by electron microscopy. The oocyte is surrounded by its envelope, and an external modification (an adhesive structure) in the surface of the envelope is present. The envelope consists of two layers, a zona radiata externa which is the site of the adhesive structure, and a zona radiata interna, which has heterogeneous, electron-dense multi layers. The surface (zona radiata externa) of the envelope in N. multifasciata is equipped with short villuslike protuberances, which have a length of 1.5~2.5 ${\mu}m$ and are separated from each other by a distance of 2~2.5 ${\mu}m$. In contrast, K. brevifasciata has undulating or wave-like structures that extend over the entire oocyte surface. The waves are 1.5~2.5 ${\mu}m$ in length and are separated a distance of 2.5~3.3 ${\mu}m$ from each other.

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Identification and Expression of Retroviral Envelope Polyprotein in the Dogfish Squalus mitsukurii

  • Kim, Soo Cheol;Sumi, Kanij Rukshana;Choe, Myeong Rak;Kho, Kang Hee
    • Journal of Marine Life Science
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    • v.1 no.2
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    • pp.88-94
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    • 2016
  • Determining the infection history of living organisms is essential for understanding the evolution of infection agents with their host, particularly for key aspects such as immunity. Viruses, which can spread between individuals and often cause disease, have been widely examined. The increasing availability of fish genome sequences has provided specific insights into the diversity and host distribution of retroviruses in fish. The shortspine spurdog (Squalus mitsukurii) is an important elasmobranch species; this medium-sized dogfish typically lives at depths of 100~500 m. However, the retroviral envelope polyprotein in dogfish has not been examined. Thus, the aim of the present study was to identify and analyze the retroviral envelope polyprotein in various tissues of dogfish. The 1334-base pair full-length novel cDNA of dogfish envelope polyprotein (dEnv) was obtained by 3' and 5'-rapid amplification of cDNA end analysis from S. mitsukurii. The open reading frame showed a complete coding sequence of 815 base pairs with a deduced peptide sequence of 183 amino acids that exhibited 34~50% identity with other fish and bird species. It was also expressed according to reverse transcription and real-time polymerase chain reaction in the kidney, liver, intestine, and lung, but not in the gill. This distribution can be assessed by identifying and analyzing endogenous retroviruses in fish, which consists of three main genes: gag, pol and env. Dogfish envelope polyprotein sequence is likely important in evolution and induces rearrangements, altering the regulatory and coding sequences. This is the first report of the identification and molecular characterization of retroviral envelope polyprotein in various tissues of S. mitsukurii.

Wind loading on trees integrated with a building envelope

  • Aly, Aly Mousaad;Fossati, Fabio;Muggiasca, Sara;Argentini, Tommaso;Bitsuamlak, Girma;Franchi, Alberto;Longarini, Nicola;Crespi, Pietro;Chowdhury, Arindam Gan
    • Wind and Structures
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    • v.17 no.1
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    • pp.69-85
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    • 2013
  • With the sustainability movement, vegetated building envelopes are gaining more popularity. This requires special wind effect investigations, both from sustainability and resiliency perspectives. The current paper focuses on wind load estimation on small- and full-scale trees used as part of green roofs and balconies. Small-scale wind load assessment was carried out using a wind tunnel testing in a global-effect study to understand the interference effects from surrounding structures. Full-scale trees were investigated at a large open-jet facility in a local-effect study to account for the wind-tree interaction. The effect of Reynolds number combined with shape change on the overall loads measured at the base of the trees (near the roots) has been investigated by testing at different model-scales and wind speeds. In addition, high-speed tests were conducted to examine the security of the trees in soil and to assess the effectiveness of a proposed structural mitigation system. Results of the current research show that at relatively high wind speeds the load coefficients tend to be reduced, limiting the wind loads on trees. No resonance or vortex shedding was visually observed.