• Title/Summary/Keyword: Envelope structure

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Seismic Performance Enhancement of Residential Flat Plate Structure by Using Base Isolation Devices. (면진장치를 사용한 주거용 무량판구조의 내진성능 향상)

  • Lee, Hyun Ho
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.11 no.3
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    • pp.185-191
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    • 2007
  • For the seismic performance enhancement of residential flat plate structure and for the selection of earthquake records, the possibility of base isolation is evaluated and the time history results are reviewed. By evaluating a base isolated stiffness, a target period, and an envelope curve analysis, seismic performance of structure, which has strong rotational mode, is evaluated. For the propriety evaluation of earthquake records usage and scaling method, time history analysis is done with variables such as DBE(design base earthquake) level, MCE(maximum considerable earthquake) level, and 1.4DBE level. From the analysis results, following conclusions can be made; the earthquake records, which are used in base isolation analysis, should be selected by similar soil type which the structure is considered, and should be intensity scaled in a range of mean ${\pm}$ standard deviation of code based design response spectrum.

An Improved Detection Technique for Spread Spectrum Audio Watermarking with a Spectral Envelope Filter

  • Jung, Sa-Rah;Seok, Jong-Won;Hong, Jin-Woo
    • ETRI Journal
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    • v.25 no.1
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    • pp.52-54
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    • 2003
  • We propose an improved algorithm for detecting audio watermarks based on a spread spectrum in the spectral domain. Since the energy of a watermark is much smaller than that of the cover audio data, pre-processing to reduce the effect of the cover data is needed to reliably extract watermarks. We introduce a spectral envelope filter as a pre-process that enhances detecting performance by filtering out the intrinsic spectral character of cover data. The proposed watermarking structure can be easily included in the compression system and can extract watermarks from partially decompressed spectral data. Our experimental results demonstrate that with a bit error rate of around 10 dB against general attacks, the proposed detecting scheme works better than detectors without the spectral filter.

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The Mechanism of Membrane Fusion During the Infection of HIV

  • Yu Yeon Gyu
    • Proceedings of the Microbiological Society of Korea Conference
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    • 2001.11a
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    • pp.97-101
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    • 2001
  • The fusion between viral envelope and target cell membrane is a central step of viral infection, and the fusion proteins located at viral envelope mediate such process. Gp41 of HIV is one of the fusion proteins whose structure and mechanism of membrane fusion had been extensively studied. Functionally important motives of gp41 are the N-terminus fusion peptide, the coiled-coil and the membrane proximal C-peptide regions. The role of these regions during the fusion process had been thoroughly examined. Specially, insertion of the fusion peptide into membrane and conformational change of the coiled-coil and C-peptide regions are assumed to be critical for the fusion mechanism. In addition, the coiled-coil region has been shown to interact with membrane, and the C-peptide region regulates the interaction in a dose dependent manner. Furthermore, fusion defective mutations of the coiled-coil region dramatically changed its binding affinity to membrane. These results suggested that the membrane binding property of the coiled-coil region is important for the fusion activity of gp41, and such property could be modulated by the interaction with the C-peptide region.

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A Study on the Kinematic and Swept Envelope of Urban Train (도시철도차량의 동적 차량한계 설정에 관한 연구)

  • 박찬경;김영국;박기준
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.05a
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    • pp.1221-1226
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    • 2001
  • A structure gauge assessment is needed to ensure that a railway vehicle can run safely along a length of track without coming unacceptably close to lineside structures or equipment, or to vehicles running on adjacent tracks. This apparently straightforward question is in reality very complicated. The amount of space required for the safe passage of a railway vehicle is significantly greater than its static body profile for a number of reasons as follows: as the vehicle runs along the track, the track input excites the vehicle and it moves on its suspension. On curved track its geometric position leads to curve overthrows. A number of different approaches have been used to answer this question and some are described and specially applied to urban train by computer simulation in this paper. The program used for calculating the kinematic and swept envelope is the VAMPIRE made in U.K.

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Wolf-Rayet star evolution with clumpy envelope structure

  • Jang, Hye-Eun;Yoon, Sung-Chul
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.42.2-42.2
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    • 2016
  • It is well known that theoretical models of Wolf-Rayet stars are not consistent with observational data in terms of temperature and stellar radius. Recent study in analytical and numerical simulations show the importance of density inhomogeneity in stellar envelope. Using 1-dimensional numerical simulations, we study how such clumpiness arisen over convective surface of Wolf-Rayet stars affect their evolutionary path. Starting from pure helium star models, we constructed 21 different initial conditions by varying stellar mass, metallicity, and the clumpiness of the sub-surface convection zone. We run the simulations until the oxygen-burning is reached and find that the influence of the clumpiness is sensitive to the initial metallicity. Our models with high metallicity including the effect of the density inhomogeneity can roughly explain the observed properties of Wolf-Rayet stars such as stellar radius and temperature. By contrast, despite a considerable amount of density inhomogeneity is given, low metallicity models could not fully explain observations. To understand the inconsistency in low metallicity models, detailed study with improved model is required, taking account of the error range of the observations.

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Soil-structure interaction and axial force effect in structural vibration

  • Gao, H.;Kwok, K.C.S.;Samali, B.
    • Structural Engineering and Mechanics
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    • v.5 no.1
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    • pp.1-19
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    • 1997
  • A numerical procedure for dynamic analysis of structures including lateral-torsional coupling, axial force effect and soil-structure interaction is presented in this study. A simple soil-structure system model has been designed for microcomputer applications capable of reflecting both kinematic and inertial soil-foundation interaction as well as the effect of this interaction on the superstructure response. A parametric study focusing on inertial soil-structure interaction is carried out through a simplified nine-degree of freedom building model with different foundation conditions. The inertial soil-structure interaction and axial force effects on a 20-storey building excited by an Australian earthquake is analysed through its top floor displacement time history and envelope values of structural maximum displacement and shear force.

Morphology and Intracellular Appearance of Euonymus Vein Clear Virus (사철나무 엽맥 바이러스의 형상과 세포내출현)

  • Chang Moo Ung
    • Korean Journal Plant Pathology
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    • v.2 no.1
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    • pp.1-11
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    • 1986
  • Negatively stained dip preparations from Euonymus showing vein clear symptoms revealed bacilliform particles. The particles tentatively referred to as the Euonymus vein clear virus(EVCV) have a relatively complex structure, measuring 230-280nm in length and 70-80nm in diameter. They have an envelope, 8-10nm thick, provided with evenly spaced beadlike projection about 5-6nm long. The inner tubular core which had no envelope showed helical structures, 200-220nm long, and 50-55nm in diameter. This inner tubular core is interpreted as the virus nucleocapsid. A striking association of virus particles with the nuclei of infected cells was apparent from sections which showed numberous virus particles at the nuclear periphery and in what appeared to be intranuclear virus particle inclusions. Careful examination of these apparent inclusions revealed the presence of the nuclear envelope surrounding them, in addition to cytoplasmic organelles within them. Such profiles were interpreted as having arisen when the sections passed through invaginations of the cytoplasm into the nucleus. In all the sections showing virus particles associated with the nucleus, large number of virus particles were found to be present in expanded areas between the two lamellae of the nuclear envelope. This location is suggested as a possible site of virus assembly. Serveal micrographs of particles found in this location suggested incorporation of the inner lamella of the nuclear envelope into the viral envelope. Various micrographs indicated a possible helical arrangement of certain components present in the virus core.

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Design of a New 3-D 16-ary Signal Constellation with Constant Envelope (상진폭 특성을 가지는 새로운 3차원 16진 신호성상도의 설계)

  • Choe, Chae-Cheol;Kang, Seog-Geun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.10
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    • pp.2149-2156
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    • 2011
  • In this paper, design of a new 3-dimensional (3-D) 16-ary signal constellation with constant envelope is presented and analyzed. Unlike the conventional 16-ary constellations, all signal points of the new constellation are uniformly located on the surface of a sphere so that they have a unique amplitude level and a symmetrical structure. When average power of the constellations is normalized, the presented 16-ary constellation has around 11.4% increased minimum Euclidean distance (MED) as compared to the conventional ones that have non-constant envelope. As a result, a digital communication system which exploits the presented constellation has 1.2dB improved symbol error rate (SER). While signal points of the conventional constant-envelope constellation are not distributed uniformly on the surface of a sphere, those of the proposed constellation has a completely symmetric distribution. In addition, the new signal constellation has much lower computational complexity for practical implementation than the conventional one. Hence, the proposed 3-D 16-ary signal constellation is appropriate for the application to a communication system which strongly requires a constant-envelope characteristic.

Ultrastructural Study to the Effects of Fel Ursi and Calculus Bovis Aqua-acupuncture (웅담(熊膽).우황(牛黃) 약침(藥鍼)의 효능(效能) 관찰(觀察)을 위한 미세구조적(微細構造的) 연구(硏究))

  • Na, Chang-Su;Kim, Jeong-Sang;Kim, Hui-Cheol;Kim, Byeong-Su;Hwang, U-Jun
    • The Journal of Korean Medicine
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    • v.18 no.1
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    • pp.430-445
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    • 1997
  • In order to know the effects of Calculus $Bovis{\cdot}F디$ Ursi aqua-acupuncture ($C{\cdot}F$ aqua-acupuncture) to the liver damage, we carried out the treatment of $C{\cdot}F$ aqua-acupuncture and injection of Kam-Du-Tang on the liver damaged rat which is induced by aconitine, and then ultrastructural study has been to the liver tissue. The results were as follows: 1. In the hepatic cell of normal group, the nuclear envelope is round and electro-density of nucleoplasm is relatively low, and have one or two large nucleolus. Cell organelle is developed rough endoplasmic reticulum(RER) and many mitochondria, glycogen granules, smooth endoplasmic reticulum(SER) and Golgi apparatus. 2. In 24 hours control group, nuclear envelope is very irregular, RER and most of cell organell is shown that destroyed by aconitine. This is similar to the 48 hours control group. In 72 hours control group, RER is recovered somewhat but cristae of mitochondria is not seen the shape 3.In 24 hours $C{\cdot}F$ aqua-acupuncture group, nuclear envelope is very irregular and cristernae is very dilatable and many mitochondria is dilationed and the cristae is not definite like the control group. In 48 hours $C{\cdot}F$ aqua-acupuncture group, nuclear envelope is relatively round and chromatin is regular. Cristernae of RER and ribosme is somewhat imperfect but is similar the normal group, and the cristae of mitchondria is shown definitely like the normal group. In 72 hours $C{\cdot}F$ aqua-acupuncture group, nuclear envelope is round and cell organell is similar to normal group. 4. In 24 hours Kam-Du-Tang group, nuclear envlope is very irregular and cell organelles are destroyed by the effects of aconitine. In 48 hours Kam-Du-Tang group, nuclear envelope is somewhat irregular but chromatin is relatively regular. RER is seperated regularly through the cytoplasm, but cannot make the structure of lamina, and cistennae is very dilationed. many of glycogen granules is seperated regularly. In 72 hours Kam-Du-Tang group, RER makes the lamina. Mitochondria is a little but inner space is dilationed so the shape of is not definite and a lot of glycogen granules are accumulated in several places. It see the above result, hepatic cell that is damaged by aconitine is effected chiefly by the $C{\cdot}F$ acupuncture and effect of acupuncture is similar to the detoxicated effect of Kam-Du-Tang.

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CNC Twisted Tube Method for 3D Coordinate Control Technology for Freeform Structure -Focused on The ARC in DaeGu- (비정형구조의 3차원 좌표제어를 위한 CNC Twisted Tube 공법 적용 -대구 대표물문화관(The ARC)를 중심으로-)

  • Ryu, Han-Guk;Kim, Sung-Jin
    • Journal of the Korea Institute of Building Construction
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    • v.13 no.5
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    • pp.434-440
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    • 2013
  • Generally, the envelope of a freeform building is composed of a structure made with rectangular or C-shaped steel pipe, and steel or aluminum panel finishes on the structure. However, these construction methods increase material loss and cost and time. There are also numerous cases of misunderstanding of design and difficulties in construction, which frequently cause construction errors. Such construction errors decrease construction productivity, resulting in poor construction quality and the need for rework, as well as cost and time overruns. To solve the problem, this study proposes a 3D coordinate control technology for freeform structure implemented through a CNC(Computerized Numerical Control) Twisted tube method, and by extension, develops a BIM-based envelope construction method for freeform building.