• Title/Summary/Keyword: vertical dimension

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Experimental Observation of New Jumping Phenomena in the Pendulum System and Its Analytical Approach (진자 시스템에서의 새로운 도약 현상의 실험적 관측과 이론적 해석)

  • 최동준;정완섭;김수현
    • Journal of KSNVE
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    • v.6 no.4
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    • pp.439-446
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    • 1996
  • This paper introduces a newly designed pendulum system that enables the more accurate boservation of dynamic behaviour arising from both horizontal and vertical(i.e. two dimension) excitation. First, experiments were carried out to examine the frequency responses of the devised pendulum system. Interestingly, experimental results for the three excitation angles of 22, 32 and 48 degree show 'new' jump phenomena. For the further understanding of these phenomena, experimental investigationhas been made to identify the equation of motion of the pendulum system from experimental data. This attempt has revealed that the viscous, coulomb and aerodynamic damping factors are involved in the equation of motion. By applying the Ritz averaging method to the equation, it becomes apparent that the jumping phenomena of the pendulum system in this work is more theoretically understood.

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The Experimental Study for Fiber Reinforced Bearing (섬유보강 탄성받침의 실험적 특성 해석)

  • 문병영;강경주;강범수;김계수;박진삼
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2001.09a
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    • pp.415-422
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    • 2001
  • In this paper, the experimental study was carried out in order to compare the mechanical characteristics of multi-layer elastomeric isolation hearings where the reinforceing elements steel plates case and fiber-reinforcement case. Fiber-reinforced isolater which has the same dimension as the steel reinforced isolator had shown better efficiency in effective damping than NRB. The compression test has shown the corresponding results with the theoretical vertical stiffness in the case of flexible reinforcement. The fiber-reinforced isolator will be significantly lighter and could lead to a much less labor intensive manufacturing process.

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Dynamic Characteristics Analysis of Mega-Float Offshore Structure (Mega-Float의 동적 특성 해석)

  • 박성현;박석주
    • Proceedings of the KSEEG Conference
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    • 2001.05a
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    • pp.66-70
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    • 2001
  • Recently, mega-float offshore structure is studied as one of the effective utilization of the ocean space. And mega-structure are now being considered for various applications such as floating airports, offshore cities and so on. This mega-float structure is relatively flexible compared with real floating structures like large ships. when we estimate dynamic responses of these structures in waves, the elastic deformation is important, because vertical dimension is small compared with horizontal. The analysis of the dynamic response as it receives regular wave is studied. The finite element method is used in the analysis of structural section of this model. And the analysis is carried out using the boundary element method in the fluid division. In order to know the characteristics of the dynamic response of the mega-float structures, effects of wavelength, water depth, and wave direction on dynamic response of the floating structure are studied by use of numerical calculation.

Gas structures and star formation in the central region of barred-spiral galaxies in self-consistent 3D simulations

  • Seo, Woo-Young;Kim, Woong-Tae
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.1
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    • pp.31.2-31.2
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    • 2017
  • The central regions of barred-spiral galaxies contain interesting gaseous structures such as dust lanes and nuclear rings with intense star formation. While our previous studies were useful in understanding the formation of these structures star formation history, they were limited to 2D isothermal galaxies in which the stellar disk and halo are modeled by fixed gravitational potentials. To study the effects of bar growth as well as the vertical dimension, we use the mesh-free hydrodynamic code named GIZMO and run 3D simulations by treating the stellar disk and halo as being live. We find that the new 3D models form the gaseous features similarly to the previous 2D models, although the detailed formation processes are quite different. For example, a ring has a large radius when it first forms and shrinks over time in the previous 2D models. In the 3D live-potential models, however, a ring forms small and grows in size with time. We present the results of the new simulations and discuss them in comparison with the previous 2D results.

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Analysis of Electron Transport in InAlAs/InGaAs HBT by Hybride Monte Carlo Simulation (Hybrid Monte Carlo 시뮬레이션에 의한 InAlAs/InGaAs HBT의 전자전송 해석)

  • 송정근;황성범;이경락
    • Electrical & Electronic Materials
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    • v.10 no.9
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    • pp.922-929
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    • 1997
  • As the size of semiconductor devices shrinks in the horizontal as well as vertical dimension it is difficult to estimate the transport-velocity of electron because they drift in non-equilibrium with a few scattering. In this paper HYbrid Monte Carlo simulator which employs the drift-diffusion model for hole-transport and Monte Carlo model for electron-transport in order to reduce the simulation time and increase the accuracy as well has been developed and applied to analyze the electron-transport in InAlAs/InGaAs HBT which is attractive for an ultra high speed active device in high speed optical fiber transmission systems in terms of the velocity and energy distribution as well as cutoff frequency.

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Development of An Onion Peeler (I) - Root cutting equiment - (양파 박피기 개발(I))

  • 민영봉;김성태;정태상;최선웅;김정호
    • Journal of Biosystems Engineering
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    • v.27 no.4
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    • pp.301-310
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    • 2002
  • With a purpose to manufacture an onion peeler, the root cutting equipment of the onion could be attached to a prototype onion peeler was developed. Before the experiment, the distribution of the dimensions of the Korean native onion were measured. And some types of the blades to cut and remove the root of the onion were designed and such characteristics as feasible revolution, conveying speed, and power requirement were investigated. From the result of the test, the selected one among the various cutters was the wing type blade with the round blade to cut out the root and with the vertical blade to cut a circular line. The optimum operating conditions of the wing type blade were revealed the revolution with no load was at 630 rpm, and the conveying speed was 0.08 m/s. Under these conditions, the maximum torque was 5.25 kg·m and the power requirement was 33 W, respectively.

Geology and Ore Deposits of the Donghae Mine, Goseong Area (경남(慶南) 고성(固城) 동해광산(東海鑛山)의 지질(地質) 및 광상(鑛床))

  • Kim, Jong Dae
    • Economic and Environmental Geology
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    • v.20 no.4
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    • pp.213-221
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    • 1987
  • The Donghae mine locates at Jangjoari, Koseongun, Kyongsang-nam-do. The geology of the mine consists of the upper part of Chin dong Formation conformably overlain by tuffaceous Koseong Formation. These formations are intruded by the granodiorite and the basic dikes. The ore mineralization occurs in the fault breccia pipe at the center of a granodiorite stock. The estimated dimension of the breccia pipe is $7m{\times}70m{\times}200m$. The host rock has distinctive hydrothermal alteration halos consisting hematite zone, chlorite zone, epidote zone and sericite zone from outer zone to the ore vein. The ore mineralization occurred in the three distinctive stages. The ore minerals formed in the first stage are pyrite, sphalerite, chalcopyrite, stannite and tetrahedrite. Galena and arsenopyrite are formed in the second stage. Some sphalerite grains include exsolution dots of the chalcopyrite. It is suggested that the ore mineralization occurred by a boiling of a hydrothermal fluid during its initial stage and subsequent cooling and $CO_2$ fugacity drop of remaining hydrothermal fluid by a ground water mixing aided vertical zoning of the ore minerals.

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A STUDY ON THE ADAPTATION OF HEAD POSTURE AFTER ACTIVATOR THERAPY IN FUNCTIONAL CLASS III MALOCCLUSION PATIENTS (Angle씨 III급 부정교합자의 Activator치료 전후 head posture변화에 관한 연구)

  • Seo, Hyung-Sik;Cha, Kyung-Suk
    • The korean journal of orthodontics
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    • v.24 no.2
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    • pp.319-329
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    • 1994
  • This study was carried out to research the adaptation patterns of head posture after activator therapy in functional class III malocclusion patients. For this purpose, 29 functional class III malocclusion patients, from the ages of 8 to 13 years old, were used. 1, Increse in capacity of oral cavity capacity were found in all the samples, but craniocervical angulation were varied into incresed group and decreased group after activator therapy. 2. Head posture exhibited the compensatory adaptation in the relative growth increments of the vertical dimension, ALFH and PLFH. 1) A group with more PLFH and less sagittal angle showed relatively small growth increment in PLFH during the treatment period, thus craniocervical angulation was increased. 2) A group with less PLFH and more sagittal angle showed relatively great growth incrmenet in PLFH during the treatment period, thus craniocervical angulation was decreased.

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An Implementation of Multiple Access Memory System for High Speed Image Processing (고속 영상처리를 위한 다중접근 기억장치의 구현)

  • 김길윤;이형규;박종원
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.29B no.10
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    • pp.10-18
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    • 1992
  • This paper considers and implementation of the memory system which provides simultaneous access to pq image points of block(p$\times$q), horizontal vector(1$\times$pq)and/vertical vector(pq$\times$1) in 2-dimension image array, where p and q are design parameters. This memory system consists of an address calculation circuit, address routing circuit, data routing circuit, module selection circuit and m memory modules where m>qp. The address calculation circuit computes pq addresses in parallel by using the difference of addresses among image points. Extra module assignment circuit is not used by improving module selection circuit with routhing circuit. By using Verilog-XL logic simulator, we verify the correctness of the memory system and estimate the performance. The implemented system provides simultaneous access to 16 image points and is 6 times faster than conventional memory system.

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Prosthodontic management of worn dentition in pediatric patient with complete overlay dentures: a case report

  • Kumar, Prince;Rastogi, Jyoti;Jain, Chandni;Singh, Harkanwal Preet
    • The Journal of Advanced Prosthodontics
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    • v.4 no.4
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    • pp.239-242
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    • 2012
  • Overlay complete dentures are simple, reversible and economical treatment modality for patients with congenital or acquired disorders that severely affect the tooth development. It satisfies both the esthetic and functional demands where the extraction of teeth is not generally indicated. In pediatric patients, the overlay dentures establish a relatively stable occlusion that improves patient's tolerance to the future treatment procedures for worn dentition. This clinical report highlights the imperative need of appropriate treatment strategy and application of maxillary and mandibular overlay dentures in a pediatric patient who suffered from congenitally mutilated and worn dentition.