• Title/Summary/Keyword: guide length

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Buckling Analysis of Guide Tube in the Spent Fuel Skeleton (핵연료 집합 구조체의 가이드튜브에 대한 죄굴응력 해석)

  • 김영환;윤지섭;정재후;홍동희;송상호
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2000.11a
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    • pp.413-416
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    • 2000
  • The spent fuel skeleton is processed in the cutting processing after compacting. If the cutting length is processed in the same interval length. The spent fuel skeleton is stayed on the connection of bottom nozzle and guide tube. In the case, because the compressive stress is loaded along the length, the guide tube is generated the buckling stress and the deforming. But the deformed guide tube interrupted the guide tube inserted through compressive room. therefore, it is experimented for the optimum buckling stress and the preventing of guide deformed. This paper is predicted the all over buckling stress of the spent fuel skeleton by using experiment. The guide of Spent fuel skeleton have buckling characteristics of the medium column. The experiment and analysis is conducted by the comparing among the equation of Euler, Johnson and Engresser. The fittest one of method is Engresser equation.

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Study on Offshore Stabbing Guide design (해양 스태빙 가이드 설계 고찰)

  • 조철희;홍성근
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1999.04a
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    • pp.69-77
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    • 1999
  • The stabbing guide is often used to guide an add-on pile into an existing pile in offshore jacket installation. It provides a pile alignment for a welding tie-in in static condition as well. Even stabbing guide is an essential component in pile installation, it is not considered as a permanent offshore structure. In this regard, there is not a define design guideline proposed. In API RP 2A WSD, it briefly define the design considerations of stabbing guide. The failure of stabbing guide can cause a greate economical loss and a serious impact to the project schedule. Stabbing guide design should consider many factors considering actual work conditions for both static and dynamic situations. In the paper, a design method is proposed by appling the plate theory and it is confirmed numerically with FEM modeling. The geometry of stabbing guide is assumed as a cylinder shape with various wall thickness and effective length. The various thickness, effective length and pile size are compared for stable stabbing guide design.

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Effect of the Shape of a Guide Grill Above a Resonance Type Sound Absorbing Panel on Intake Flow into a Resonator (공명 흡음판 위 가이드 그릴의 형상이 공진기 흡입 유동에 미치는 영향)

  • Bae, Hyunwoo;Sung, Jaeyoung;Lee, Dong Hoon
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.25 no.3
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    • pp.182-188
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    • 2016
  • This study investigates cavity flows through a guide grill above a resonator. Vortex distributions and intake flows are simulated for various shapes of the guide grill. The flows are assumed to be compressible, unsteady, and turbulent. Numerical simulations are conducted using a large eddy simulation (LES) model. To analyze the effect of the guide grill shape, three cavity lengths (0.2H, 0.6H, and 1.0H) and cavity angles ($30^{\circ}$, $45^{\circ}$ and $60^{\circ}$) are considered based on resonator height (H). The results show that the vortex generated in the resonator by cavity flow increases with cavity length. Thus, the intake flow is minimum at the smallest cavity length and angle. However, when cavity length is equal to resonator height, the intake flow decreases. The maximum intake flow occurs at a cavity angle $45^{\circ}$ at higher cavity lengths owing to the interaction between the vortex in the resonator and intake flow.

A practical guide to maximizing sample peak capacity for complex low molecular mass molecule separations. (복잡한 저분자량 분자 분리를 위한 시료 피크 용량 극대화 가이드)

  • Arianne Soliven;Matt James;Tony Edge
    • FOCUS: LIFE SCIENCE
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    • no.1
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    • pp.9.1-9.5
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    • 2024
  • Method development for complex low molecular mass (LMM) samples using reversed-phase (RP) separation conditions presents significant challenges due to the presence of many unknown analytes over wide concentration ranges. This guide aims to optimize method parameters-column length (L), temperature (T), flow rate (F), and final mobile phase conditions (Øfinal)-to maximize separation peak capacity. Validated by prior research, this protocol benefits laboratories dealing with metabolomics, natural products, and contaminant screening. This practical guide provides a structured approach to maximizing peak capacity for complex LMM separations. It complements computational optimization strategies and offers a step-by-step method development process. The Snyder-Dolan test is highlighted as essential for determining the need for gradient or isocratic elution and guiding column length decisions. The decision tree framework helps analysts prioritize variable optimization to develop effective separation methods for complex samples.

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Thermal neutron albedo and flux for different geometries neutron guide

  • Azimkhani, S.;Rezaei Ochbelagh, D.;Zolfagharpour, F.
    • Nuclear Engineering and Technology
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    • v.51 no.4
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    • pp.1075-1080
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    • 2019
  • This paper presents a study on thermal neutron reflection properties of neutron guide for cylinder, spindle, elliptic and parabolic geometries using $^{241}Am-Be$ neutron source (5.2 Ci) and $BF_3$ detector, whereas neutron guide is important instrument for transportation of neutrons. To this goal, the required inner and outer radii of neutron guide have been calculated to achieve the highest guided thermal neutron flux based on MCNPX Monte Carlo code. The maximum flux of cylinder geometry with a length 50 cm has been obtained at an inner radius 9 cm and an outer radius 21 cm. Also, the maximum value of thermal neutron albedo is $0.46{\pm}0.001$ at 12 cm thickness of parabolic guide.

Implementation of Cervical Pedicle Surgical Guide for Safe Surgery

  • Kwak, Ho-Young;Huh, Jisoon;Lee, Won-Joo
    • Journal of the Korea Society of Computer and Information
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    • v.22 no.12
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    • pp.125-130
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    • 2017
  • Screw insertion surgery is frequently required among surgical procedures. Especially, very careful attention should be paid to the insertion of screw in the operation of the cervical vertebra. Therefore, there is a need for a guide that allows the surgeon to reliably and promptly perform treatment by calculating the desired insertion angle and length for screw insertion. In this study, the center and direction of the pedicle were calculated through 3D modeling and 3D vector numerical analysis using the CT or MRI image of the patient for the safe operation of the guide, and based on this, After that, we will implement surgical guide based on this.

Performance Improvement of Cylindrical Turbine Guide Bearings with Pad Leading-Edge Tapers for Vertical Hydro-Power Application: Effects of Taper Angle and Length (패드 선단 테이퍼를 갖는 수력 수직 원통형 터빈 가이드 베어링의 성능향상 - 테이퍼 각도와 길이의 영향)

  • Lee, An Sung;Jang, Sun-Yong;Park, Soo Man
    • Tribology and Lubricants
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    • v.34 no.1
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    • pp.16-22
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    • 2018
  • Cylindrical turbine guide bearings (TGBs) with simple plain pads have conventionally been used in vertical hydro-power turbine-generator applications in order to provide turbine runner shafts with smooth rotation guides and supports. To overcome low-load/low-eccentricity performance drawbacks, such as very low film stiffness and lack of design credibility in the stiffness values themselves, of conventional cylindrical TGBs, the introduction of a rotational-directional leading-edge taper to each partitioned pad, simply pad leading-edge taper, has been found to be very effective in enhancing their design-application availability and usefulness. In this study, we investigate the effects of taper angle and length for given taper heights in detail in order to systematically establish the effectiveness of design on the performance improvement of vertical hydro-power application cylindrical TGBs with pad leading-edge tapers. The analysis results with $4-Pad{\times}1-Row$ cylindrical TGBs show that the lubrication performance of the cylindrical TGBs is optimized with an approximate taper angle ratio of 0.8 and taper length ratio of 0.9. We conclude that the introduction of pad leading-edge tapers along with the optimization of taper designs can be very effective in improving the overall operation reliability of cylindrical TGBs and the rotordynamic characteristics of vertical hydro-power turbine-generator rotor-bearing systems as well, to which the TGBs are applied.

LED Light Coupler Design for a Ultra Thin Light Guide

  • Lee, J.H.;Chang, W.;Choi, D.
    • Journal of the Optical Society of Korea
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    • v.11 no.3
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    • pp.113-117
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    • 2007
  • A LED light coupler is proposed for coupling light from a mini side LED of 0.4 mm height to a very thin (${\sim}0.3 mm$) light guide. Due to the ultra thinness of the light guide, conventional light couplings between LEDs and light guides do not provide adequate coupling efficiency. The designed LED coupler is a compound lens of 3.5 mm length, 1.2 mm height, and 3.3 mm width. The courier first collimates the light from the LED and then concentrates the light in a manner similar to a compound parabolic concentrate, (CPC) into the light guide. The exit surface of the coupler is additionally textured to have micro patterns in order to control the radiance profile.

ADPI Characteristics of a Line-Diffuser (라인-디퓨저의 ADPI특성에 관한 연구)

  • Lee, Jae-Heon;Cho, Young-Jin;Kang, Seok-Youn;Oh, Myung-Do
    • Proceedings of the KSME Conference
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    • 2001.11b
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    • pp.958-964
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    • 2001
  • It is difficult to apply a conventional selection guide for diffusers when the diffuser is installed in a perimeter zone, because the ADPI(Air Diffusion Performance Index) vs. T/L(Throw/Length) curve listed in conventional guide does not consider the perimetric heating load. The objective of this study is to evaluate the effect of the perimetric heating load on the ADPI and to propose a selection guide for proper diffuser when perimetric heating load exists. The velocity and temperature distributions and the ADPI value are obtained numerically with various heat load ratios and air flow rates. The ADPI values by numerical result were compared with existing experimental data to verify the method for evaluation of ADPI proposed in present study. In case of a high side wall diffuser, the ADPI decreased with increases of the flow rate on every heat load ratio of present study except 0.75. Also, the ADPI vs. T/L curves have been proposed for the heat load ratios of 0.25, 0.5, 0.75 to guarantee comport thermal environment when diffusers are installed in perimeter zone.

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