• Title/Summary/Keyword: functional element

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Adaptive Mesh Refinement Using Viscous Adjoint Method for Single- and Multi-Element Airfoil Analysis

  • Yamahara, Toru;Nakahashi, Kazuhiro;Kim, Hyoungjin
    • International Journal of Aeronautical and Space Sciences
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    • v.18 no.4
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    • pp.601-613
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    • 2017
  • An adjoint-based error estimation and mesh adaptation study is conducted for two-dimensional viscous flows on unstructured hybrid meshes. The error in an integral output functional of interest is estimated by a dot product of the residual vector and adjoint variable vector. Regions for the mesh to be adapted are selected based on the amount of local error at each nodal point. Triangular cells in the adaptive regions are refined by regular refinement, and quadrangular cells near viscous walls are bisected accordingly. The present procedure is applied to single-element airfoils such as the RAE2822 at a transonic regime and a diamond-shaped airfoil at a supersonic regime. Then the 30P30N multi-element airfoil at a low subsonic regime with a high incidence angle (${\alpha}=21deg.$) is analyzed. The same level of prediction accuracy for lift and drag is achieved with much less mesh points than the uniform mesh refinement approach. The detailed procedure of the adjoint-based mesh refinement for the multi-element airfoil case show that the basic flow features around the airfoil should be resolved so that the adjoint method can accurately estimate an output error.

Study on the magnetic flux distribution of transformer by the use of finite element method (유한요소법에 의한 변압기의 자속분포 해석에 관한 연구)

  • 임달호;현동석;이철직
    • 전기의세계
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    • v.29 no.4
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    • pp.247-255
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    • 1980
  • In this study, an application of Finite Element Method which, in principle, based on variational calculus has been presented for the two-dimensional analysis of magnetic flux distribution in the shell type core of single phase transformer. The necessary stationarity condition of energy functional and boundary conditions were determined under the assumptions that the electromagnetic field considered is stationary and that the effect of eddy current is negligible. In the process of application the domain of magnetic field was divided into triangle subsectional elements and then the matrix equations were constructed for the respective triangular element and for those of all after the manipulation of minimization process to the vector potential of magnetic field at the each vertex of the element. Furthermore the numerical computation for the equations was guided by the Gaussian Elimination Methods. As the results obtained, it is found that the aspect of magnetic flux distribution inside the core as well as the leakage flux profile at the vicinity of the inner leg of the core is not much different from the well-known distribution profile of magnetic flux, however, the procedure shows to possess the merit of the uniquely deterministic nature for the flux distribution at the desired points.

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A Software Architecture for High-speed PCE (Path Computation Element) Protocol (고성능 PCE (Path Computation Element) 프로토콜 소프트웨어 구조)

  • Lee, Wonhyuk;Kim, Seunhae;Kim, Hyuncheol
    • Convergence Security Journal
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    • v.13 no.6
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    • pp.3-9
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    • 2013
  • With the rapidly changing information communication environment and development of technologies, the informati on networks are evolved from traditional fixed form to an active variable network that flexible large variety of data can be transferred. To reflect the needs of users, the next generation using DWDM (Dense Wavelength Division M ultiplexing) transmission system and OXC (Optical Cross Connect) form a dynamic network. After that GMPLS (Ge neralized Multi-Protocol Label Switching) can be introduced to dynamically manage and control the Reconfigurable Optical Add-drop Multiplexer (ROADM)/Photonic Cross Connect (PXC) based network. This paper propose a softw are architecture of Path Computation Element (PCE) protocol that has proposed by Internet Engineering Task Force (IETF) to path computation. The functional blocks and Application Programming Interface (API) of the PCE protoco l implementation are also presented.

An Estimative Model of Spot Weld Failure-1. Failure Criteria (점 용접점 파단의 정량적 모델-1. 파단조건식)

  • Lee, T.S.;Lee, H.Y.;Shin, S.J.
    • Transactions of the Korean Society of Automotive Engineers
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    • v.6 no.6
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    • pp.40-52
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    • 1998
  • A good grasp of the failure mechanisms of resistance spot weld, widely used in joining the auto-panels, in essential to the structural/crashworthy analyses and integrity assessment of the whole auto-body. In this study, We provide an estimative model describing the failure behavior of resistance spotf weld, and apply the model to the finite element analysis of crashworthiness. First, in "Part 1-Failure Criteria", to be used for the finite element analysis of spot-welded structural panels of an auto-body, (i) a methodology for quantifying the spot weld failure and the accompanying failure criteria are presented, and (ii) the coefficients of the failure equation are determined by a munimum number of appropriate experimental tests. To achieve these, we derive the functional form of the failure envelop by limit analysis, and correlate it with the form in PAM-$CRASH^{TM}$ code, and also investigate the effect of the failure coefficients on the failure envelop form. An estimative model obtained in this Part1, as spot weld failure criteria is applied to the Macroscopic finite element analysis of autobody structural panels using PAM-$CRASH^{TM}$ code in Part 2.

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Women's perceptions of physical deformation from aging and demand on postural correction wear (노화에 따른 여성의 신체변화 자각과 자세교정 기능성 의류 수요 특성)

  • Lee, Suyeon;Chun, Jongsuk
    • The Research Journal of the Costume Culture
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    • v.20 no.5
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    • pp.725-735
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    • 2012
  • This study investigated the demand for functional clothing that compensates for the physical deformation of women due to aging. For this, the degree of perception of physical deformation at the new silver generation was examined. The demand for functional clothing that corrects body shape and posture according to differences in age and degree of perception was analyzed. Study participants(n=138) were women who ranged from 55 to 65 in age. Perception of physical deformation was investigated in the categories of deformation of body posture, cognition of joint pain, and deformation of body shape. Analysis results showed that cognition of joint pain was the largest of the three elements of body deformation, and each element had a high correlation between each other. Perception for degree of body deformation for women in their 50's and 60's was similar. These results show that changes in posture or body shape occur severely from the late 50's, and this appears as joint pain. The group with a high perception of posture deformation showed an especially high demand for functional clothing that corrects body shape and posture. The group with a high perception of body shape deformation had high demand for functional clothing that corrects body shape by lifting the hips and the breasts, and making the abdomen and waist slimmer. The results of this study show that women of the new silver generation are attuned to deformations in body shape and posture as well as joint pain beginning in their mid-fifties. There is a need to develop functional clothing to correct posture and body shape for the new silver generation women.

Effects of Panicum miliaceum L. extract on adipogenic transcription factors and fatty acid accumulation in 3T3-L1 adipocytes

  • Park, Mi-Young;Seo, Dong-Won;Lee, Jin-Young;Sung, Mi-Kyung;Lee, Young-Min;Jang, Hwan-Hee;Choi, Hae-Yeon;Kim, Jae-Hyn;Park, Dong-Sik
    • Nutrition Research and Practice
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    • v.5 no.3
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    • pp.192-197
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    • 2011
  • The dietary intake of whole grains is known to reduce the incidence of chronic diseases such as obesity, diabetes, cardiovascular disease, and cancer. To investigate whether there are anti-adipogenic activities in various Korean cereals, we assessed water extracts of nine cereals. The results showed that treatment of 3T3-L1 adipocytes with Sorghum bicolor L. Moench, Setaria italica Beauvois, or Panicum miliaceum L. extract significantly inhibited adipocyte differentiation, as determined by measuring oil red-O staining, triglyceride accumulation, and glycerol 3-phosphate dehydrogenase activity. Among the nine cereals, P. miliaceum L. showed the highest anti-adipogenic activity. The effects of P. miliaceum L. on mRNA expression of peroxisome proliferator-activated receptor-${\gamma}$, sterol regulatory element-binding protein 1, and the CCAAT/enhancer binding protein-${\alpha}$ were evaluated revealing that the extract significantly decreased the expression of these genes in a dose-dependent manner. Moreover, P. miliaceum L. extract changed the ratio of monounsaturated fatty acids to saturated fatty acids in adipocytes, which is related to biological activity and cell characteristics. These results suggest that some cereals efficiently suppress adipogenesis in 3T3-L1 adipocytes. In particular, the effect of P. miliaceum L. on adipocyte differentiation is associated with the downregulation of adipogenic genes and fatty acid accumulation in adipocytes.

The research regarding the energy storage device which applies the carbon nanotube (탄소나노튜브를 활용한 에너지 저장 소자에 관한 연구)

  • Kim, Do-Hwan;Kang, Soon-Duk
    • The Journal of Information Technology
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    • v.10 no.2
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    • pp.37-45
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    • 2007
  • The multiple-ability which the structure and the physical properties which the carbon or scull tube are unique show the applicability is superior in the plane indication element which is an indispensability of information communications apparatus, the stubbornness memory element, 2nd change of air and the rough copy dosage [khay] plaque seater, the hydrogen store material and the chemical sensor back and it has the possibility which will pass over the limit which the element of existing has. from the present paper it compared in the steel and only 10 the boat it did and it analyzed against an energy storage space voluntary application and developmental apply the carbon or scull tube trend in order about under researching the effective energy storage element it could be appeared, the technique of the strong carbon nano tube. 1. The hazard which embodies the energy storage element which uses the carbon or scull tube it follows in the function which stands and CNT of the structure which is various is necessary. 2. CNT fabrications of each one must precede possible not only must be each Cabinet conference circumstances quality gain and loss. 3. The structural control of syntheses, length controls, diameter controls and the metal - CNT junction control backs of quality CNT must precede. Applies the hereafter carbon or the scull tube in the various element with the primary preceding base technique for the structural plan technique of the carbon or scull tube to be certainly established, it does, secondarily the various element functional control technique which uses the carbon or scull tube is researched and will do.

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Design and Implementation of Path Computation Element Protocol (PCEP) - FSM and Interfaces (Path Computation Element 프로토콜 (PCEP)의 설계 및 구현 - FSM과 인터페이스)

  • Lee, Wonhyuk;Kang, Seungae;Kim, Hyuncheol
    • Convergence Security Journal
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    • v.13 no.4
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    • pp.19-25
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    • 2013
  • The increasing demand for fast, flexible and guaranteed Quality of Service (QoS) in core networks has caused to deploy MultiProtocol Label Switching (MPLS) and Generalized MPLS (GMPLS) control plane. In GMPLS control plane, path computation and cooperation processes are one of the crucial element to maintain an acceptable level of service. The Internet Engineering Task Force (IETF) has proposed the Path Computation Element (PCE) architecture. The PCE is a dedicated network element devoted to path computation process and communications between Path Computation Clients (PCC) and PCEs is realized through the PCE Protocol (PCEP). This paper examines the PCE-based path computation architecture to include the design and implementation of PCEP. The functional modules including Finite State Machine (FSM) and related key design issues of each state are presented. In particular we also discuss internal/external protocol interfaces that efficiently control the communication channels.

Development of the Functional Shoe Apparatus using FEM (유한요소법을 이용한 기능성 신발 구조체의 개발)

  • Han, Kyu-Taek
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.12 no.3
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    • pp.89-95
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    • 2013
  • This study focused on the development on functional shoe apparatus so that the appropriate impact can be applied to the feet in order to improve the density of mineral bone at lower limbs. The model with structure proposed in this study had an effective stress about 20 to 100% higher by comparing that of the model without it among most of 15 bone extraction points. Though there is a limitation that the finite element analysis data from the human body model are not the value of mineral bone densities by measuring directly but the effective bone stresses against impact, the proposed structure is designed to influence the increase of bone mass and improve the density of mineral bone by effecting the improvement of the density of mineral bone actually.

The Study of FUSE Installing of PT in the trend of Digitalization and Convergence of Power Machinery. (디지탈화 및 복합화된 전력기기 변성기용 퓨즈 설치의 문제점)

  • Ok Yeon Ho;Lee Hyoung Mook;Hong Yeong Jae;Lee Eun Woong
    • Proceedings of the KIEE Conference
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    • summer
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    • pp.357-359
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    • 2004
  • Fuse is the initial equipment of Protective Relay The installation standard of Fuse has been used for long time in Power Facilities. However according to the innovative development of Electric & Electronic element(=semiconductor) Technology, Protective Relay and other Power Equipments are being changed into Digitalization and Multi-Functional Convergence. In contrast with it, the installation standard of Fuse is just the same. There is a need to give careful consideration to it. This study will bear a Part of producing a safe and efficient Power by examining the current installation of primal 8f secondary 1'use in multi-functional PT of Power plant, giving a problem careful consideration and suggesting suitable countermeasures.

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