• Title/Summary/Keyword: two dimensions

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Dune Migration on an Offshore Sand Ridge in the Southern Gyeonggi Bay, Korea (경기만 남부지역 사퇴 위에 발달된 dune의 이동)

  • Kum, Byung-Cheol;Shin, Dong-Hyeok
    • Ocean and Polar Research
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    • v.35 no.1
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    • pp.51-61
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    • 2013
  • Two surveys were conducted in January 2006 and September 2007 with multibeam echosounder to investigate the dune shape, migration rate, and bedload transport rate using dune-tracking method on an offshore sand ridge at southern Gyeonggi Bay. The migration rates of dunes range from 1.8 $myr^{-1}$) to 56.0 $myr^{-1}$), at the upper northwestern side of sand ridge towards the southwest direction and from the center of the sand ridge towards the northeast direction respectively. Large (i.e. length 10-100 m) dunes show faster migration (0.3-23.4 $myr^{-1}$) ) than very large (i.e. length > 100 m) dunes because larger dunes have required a larger volume of sediments to be displaced. The decreases in dimensions and migration rates of dunes from the center of sand ridge to the lower part of southeastern side on the sand ridge can be ascribed to the decrease of sandy sediments availability, tidal currents with depth, and the coarsening of surface sediments from the crest of the sand ridge to the trough. Bedload transport rates on the basis of migration rates and dune dimensions decrease from 74.5 $m^2yr^{-1}$) at C transect to 35.6 $m^2yr^{-1}$) at R-02 transect.

Proposal of an Improved Concept Design for the Deep Geological Disposal System of Spent Nuclear Fuel in Korea

  • Lee, Jongyoul;Kim, Inyoung;Ju, HeeJae;Choi, Heuijoo;Cho, Dongkeun
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.18 no.spc
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    • pp.1-19
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    • 2020
  • Based on the current high-level radioactive waste management basic plan and the analysis results of spent nuclear fuel characteristics, such as dimensions and decay heat, an improved geological disposal concept for spent nuclear fuel from domestic nuclear power plants was proposed in this study. To this end, disposal container concepts for spent nuclear fuel from two types of reactors, pressurized water reactor (PWR) and Canada deuterium uranium (CANDU), considering the dimensions and interim storage method, were derived. In addition, considering the cooling time of the spent nuclear fuel at the time of disposal, according to the current basic plan-based scenarios, the amount of decay heat capacity for a disposal container was determined. Furthermore, improved disposal concepts for each disposal container were proposed, and analyses were conducted to determine whether the design requirements for the temperature limit were satisfied. Then, the disposal efficiencies of these disposal concepts were compared with those of the existing disposal concepts. The results indicated that the disposal area was reduced by approximately 20%, and the disposal density was increased by more than 20%.

A BAFFLE DESIGN FOR AN AIRGLOW PHOTOMETER ON BOARD THE KOREA SOUNDING ROCKET-III

  • LEE YOUNG SUN;KIM YONG HA;YI YU;KIM JHOON
    • Journal of The Korean Astronomical Society
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    • v.33 no.3
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    • pp.165-172
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    • 2000
  • A baffle system for an airglow photometer, which will be on board the Korea Sounding Rocket-III(KSR-III), has been designed to suppress strong solar scattered lights from the atmosphere below the earth limb. Basic principles for designing a baffle system, such as determination of baffle dimensions, arrangement of vanes inside a baffle tube, and coating of surfaces, have been reviewed from the literature. By considering the constraints of the payload size of the KSR-III and the incident angle of solar light scattered from the earth limb, we first determined dimensions of a two-stage baffle tube for the airglow photometer. We then calculated positions and heights of vanes to prohibit diffusely reflected lights inside the baffle tube from entering into the photometer. In order to evaluate performance of the designed baffle system, we have developed a ray tracing program using a Monte Carlo method. The program computed attenuation factors of the baffle system on the order of $10^{-6}$ for angles larger than $10^{\circ}$, which satisfies the requirements of the KSR-III airglow experiment. We have also measured the attenuation factors for an engineering model of the baffle system with a simple collimating beam apparatus, and confirmed the attenuation factors up to about $10^{-4}$. Limitation of the apparatus does not allow to make more accurate measurements of the attenuation factors.

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Concept Analysis of Health Literacy for Patients with Cardiovascular Disease using Hybrid Model

  • Sim, Jeong Eun;Hwang, Seon Young
    • Research in Community and Public Health Nursing
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    • v.30 no.4
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    • pp.494-507
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    • 2019
  • Purpose: The purpose of this study is to provide a clear definition of the health literacy for patients with cardiovascular disease by analyzing the dimensions and properties using Hybrid concept analysis. Methods: The concept of health literacy of patients with cardiovascular disease was analyzed according to the cyclic process of theoretical phase-field work phase-final analysis phase presented in the Hybrid model. We reviewed 26 literatures and conducted in-depth interviews with 13 patients with cardiovascular disease. Results: The concept of health literacy in cardiovascular patients is derived from two dimensions and five attributes. Literacy skills, health information search ability and health information utilization skills were derived as attributes in the individual functional dimension, while active communication with the medical team and utilization of health information support resources were derived at the interrelational dimension. It is defined as the individualized and integrated ability of an individual to explore and utilize the various health information needed to make appropriate health decisions during the chronic course after diagnosis of cardiovascular disease, to communicate proactively with medical staffs and to utilize support resources. Conclusion: This study will contribute to the development and related research of health literacy measurement tools that can be used in cardiovascular nursing practice based on the attributes and indicators of health literacy for patients with cardiovascular disease.

A study on Auto-drawing for Involute Curve and Trochoidal fillet curve (인벌류트 커브와 트로코이드 필렛 커브의 자동생성에 관한 연구)

  • Kim, M.J.;Prak, J.H.;Kim, T.H.;Lee, S.S.;Jeon, E.C.
    • Proceedings of the KSME Conference
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    • 2001.11a
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    • pp.834-840
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    • 2001
  • Gear is general mechanical elements that used for power transmission between two shafts that interval is comparatively short. and it delivers big power as accurate ratio of speed. The profile of Spur gear which is the most basic factor is divided into Trochoidal fillet curve and Involute curve. Involute curve is used a lot of a shaped curve of machine parts such as a gear, a scroll compressor and a collar of centrifugal pump. However, It is poor to study the modeling of Trochoidal fillet curve and the three dimensions model shaped mathematical curve. This paper describes a mathematical model of profile shifted involute gear. and this model is based on Camus's theory. We draw three dimensions gear have accurate mathematical function using ADS, VisualLISP. and To check accuracy and perfection, we make a program of checking Interference. and use for this study.

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Dimension Measurement for Large-scale Moving Objects Using Stereo Camera with 2-DOF Mechanism (스테레오 카메라와 2축 회전기구를 이용한 대형 이동물체의 치수측정)

  • Cuong, Nguyen Huu;Lee, Byung Ryong
    • Journal of the Korean Society for Precision Engineering
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    • v.32 no.6
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    • pp.543-551
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    • 2015
  • In this study, a novel method for dimension measurement of large-scale moving objects using stereo camera with 2-degree of freedom (2-DOF) mechanism is presented. The proposed method utilizes both the advantages of stereo vision technique and the enlarged visibility range of camera due to 2-DOF rotary mechanism in measuring large-scale moving objects. The measurement system employs a stereo camera combined with a 2-DOF rotary mechanism that allows capturing separate corners of the measured object. The measuring algorithm consists of two main stages. First, three-dimensional (3-D) positions of the corners of the measured object are determined based on stereo vision algorithms. Then, using the rotary angles of the 2-DOF mechanism the dimensions of the measured object are calculated via coordinate transformation. The proposed system can measure the dimensions of moving objects with relatively slow and steady speed. We showed that the proposed system guarantees high measuring accuracy with some experiments.

CFD Analysis for the Design of a Venturi Tube-type Air Bubble Generator with Porous Material Throat (다공성 재질의 목을 가진 벤츄리 관 공기방울 발생장치의 설계를 위한 유동해석)

  • Yun, Jeong-Eui
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.40 no.10
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    • pp.667-672
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    • 2016
  • The goal of this study was to develop a venturi-type air bubble generator with a porous material throat. Using the two-phase multi-flow CFD analysis for the venturi tube, researchers determined the optimal design of major dimensions, such as the venturi throat length and diameter, in order to control the performance of the air bubble supply through the porous material throat in a venturi tube. Researchers then determined the relationship between the flow rate of supply water and the major design dimensions of the venturi-type air generator for maximizing the performance of the air bubble supply through the porous material throat in a venturi tube.

A study on procedure for classifying male muscular lower body somatotype from general anthropometric database

  • Lee, Minji;Chun, Jongsuk
    • The Research Journal of the Costume Culture
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    • v.21 no.4
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    • pp.585-595
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    • 2013
  • The most researches developing pattern of compression style sportswear were targeted at the live model that has muscular body build. The purpose of this study was developing a method for classifying men's lower body types in terms of muscular body build. The 3D human body scan data and body measurements of 30s of Size Korea were analyzed. The subjects (n=203) were men between the ages of 30 and 39 years. Men's muscular body build was classified with two key dimensions, thigh girth and calf girth. The subjects were divided into four groups. From each group, average subjects (n=42) whose height and weight were close to the mean value ($mean{\pm}1/2$ S.D.) were selected. 42 subjects were divided up as four groups. Group I (n=7) was thigh and calf developed body type. Group II (n=9) was thigh developed body type. Group III (n=11) was calf developed body type. Group IV (n=15) was thigh and calf undeveloped body type. Four groups had distinct different at widths (n=4), depths (n=4), and girths (n=9) dimensions. The results showed that the muscular men in their 30s could be defined by thigh and calf girths. The thigh developed muscular men had thigh girth over 60cm and the calf developed muscular men had calf girth over 38cm. From each group one representative was selected by 3D body scan figure.

Effects of exhaust pipe curvature on the performance of a 4 cycle diesel engine (디이젤 엔진에서 排氣管 屈曲이 엔진性能에 미치는 影響)

  • 문병수;서정윤
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.10 no.5
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    • pp.735-741
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    • 1986
  • An experimental study on the effects of exhaust pipe curvature on the performance of a diesel engine is presented. The experiments were carried out on a 4-cycle, 216 c.c diesel engine and two types of pipe curvature, circular arc and rectangle, were tested. The shaft output, shaft torque and specific fuel consumption were obtained by inserting bent pipes of different dimensions into the exhaust pipe at various engine operation conditions. It was found that the engine performance was decreased by the circular arc bent pipe and the effects were dominated by its arc angle. The decrease of engine performance was minimized by the arc angle of 180.deg.. By the rectangle pipes the performance was more decreased and the effects were little influenced by its dimensions.

A P-HIERARCHICAL ERROR ESTIMATOR FOR A FEM-BEM COUPLING OF AN EDDY CURRENT PROBLEM IN ℝ3 -DEDICATED TO PROFESSOR WOLFGANG L. WENDLAND ON THE OCCASION OF HIS 75TH BIRTHDAY

  • Leydecker, Florian;Maischak, Matthias;Stephan, Ernst P.;Teltscher, Matthias
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.17 no.3
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    • pp.139-170
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    • 2013
  • We extend a p-hierarchical decomposition of the second degree finite element space of N$\acute{e}$d$\acute{e}$lec for tetrahedral meshes in three dimensions given in [1] to meshes with hexahedral elements, and derive p-hierarchical decompositions of the second degree finite element space of Raviart-Thomas in two dimensions for triangular and quadrilateral meshes. After having proved stability of these subspace decompositions and requiring certain saturation assumptions to hold, we construct a local a posteriori error estimator for fem and bem coupling of a time-harmonic electromagnetic eddy current problem in $\mathbb{R}^3$. We perform some numerical tests to underline reliability and efficiency of the estimator and test its usefulness in an adaptive refinement scheme.