• Title/Summary/Keyword: notch type

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A Study on the Fatigue Strength Evaluation in Rail-type Expansion Joint Weldment of Bridge (레일형 교량신축이음장치 용접부의 피로강도 평가에 관한 연구)

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    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1998.10a
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    • pp.115-120
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    • 1998
  • This paper is especially concerned with the weldment between support beam and square bar that plays important roles in control box of Expansion Joint as a bridge structure. Fatigue strength of the weldment is dependent on notch radius from welding defects and material properties. From which, tensile strength($\sigma$ult) and fatigue notch factor(Kf) become important factors to predict fatigue life. The fatigue notch sensitivity(η) for metals can be divided into two types : high and low notch sensitivity. In this work, the Expansion Joint weldment was found to have low notch sensitivity. Fatigue test of real structure was performed up to 106cycles to be compared with predicted endurance limit.

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A Study of Cogging Torque Reduction depending on Notch Position of Single Phase BLDC Motor Stator (단상 BLDC 전동기 고정자 노치 위치에 따른 코깅토크 저감에 관한 연구)

  • Kam, Seung-Han;Jung, Tae-Uk
    • Journal of the Korean Society of Industry Convergence
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    • v.17 no.3
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    • pp.113-121
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    • 2014
  • This paper presents a optimization design of 10[W] single phase BLDC motor applied Notch shape. Cogging Torque causes noise, vibration and torque ripple so notched stator is proposed in this paper. Firstly, a single phase BLDC motor needs applying aymmetric air-gap shape because this type motor cannot help having dead-point which is zero torque position. However, using asymmetric air-gap structure causes cogging torque increase. Therefore, this paper proposes the notch shape structure. Notch shape structure has some advantages; low cost, easy to apply. There are 4 optimal factors selected in optimization process, which are position and size of notches. Through building a prototype, the result of FE analysis and the experimental measurement value are compared each other and then vailidity and utility of simulation will be verified.

Performance Analysis of th e Sign Algorithm for an Adaptive IIR Notch Filter with Constrained Poles and Zeros

  • Tani, Naoko;Xiao, Yegui
    • Proceedings of the IEEK Conference
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    • 2000.07b
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    • pp.681-684
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    • 2000
  • Gradient-type algorithms for adaptive IIR notch filters are very attractive in terms of both performances and computational requirements. Generally, it is quite difficult to assess their performances analytically. There have been several trials to analyze such adaptive algorithms as the sign and the plain gradient algorithms for some types of adaptive IIR notch filters, but many of them still remain unexplored. Furthermore, analysis techniques used in those trials can not be directly applied to different types of adaptive IIR notch filters. This paper presents a detailed performance analysis of the sign algorithm for a well-known adaptive IIR notch filter with constrained poles and zeros, which can not be done by just applying the related existing analysis techniques, and therefore has not been attempted yet. The steady-state estimation error and mean square error (MSE) of the algorithm are derived in closed forms. Stability bounds of the algorithm are also assessed. extensive simulations are conducted to support the analytical findings.

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Controlled Microstructure for Optimum Fatigue Performance

  • Takeda, Yoshinobu;Bergmark, Anders;Alzati, Luigi;Bengtsson, Sven
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09a
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    • pp.132-133
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    • 2006
  • Optimized choice of material for two principally different types of PM components is presented. The first is characterized by high stresses in areas with high stress concentrations (for example synchronizer hubs with very sharp notches, typically <0.25mm in the pre-synchronizer slot and the inner splines). The second type has slightly larger notch radii (small spur gears and sprockets with typically notch radii between 1- 3mm). Diffusion alloyed materials are well suited for sharp notch components. Pre-alloyed materials are also well suited for applications with sharp notches if compressive residual stresses in the notch roots are created by appropriate process control. A free choice of material is available for components with the larger notch radii.

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Mind Bomb-2 Regulates Hippocampus-dependent Memory Formation and Synaptic Plasticity

  • Kim, Somi;Kim, TaeHyun;Lee, Hye-Ryeon;Kong, Young-Yun;Kaang, Bong-Kiun
    • The Korean Journal of Physiology and Pharmacology
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    • v.19 no.6
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    • pp.515-522
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    • 2015
  • Notch signaling is a key regulator of neuronal fate during embryonic development, but its function in the adult brain is still largely unknown. Mind bomb-2 (Mib2) is an essential positive regulator of the Notch pathway, which acts in the Notch signal-sending cells. Therefore, genetic deletion of Mib2 in the mouse brain might help understand Notch signaling-mediated cell-cell interactions between neurons and their physiological function. Here we show that deletion of Mib2 in the mouse brain results in impaired hippocampal spatial memory and contextual fear memory. Accordingly, we found impaired hippocampal synaptic plasticity in Mib2 knock-out (KO) mice; however, basal synaptic transmission did not change at the Schaffer collateral-CA1 synapses. Using western blot analysis, we found that the level of cleaved Notch1 was lower in Mib2 KO mice than in wild type (WT) littermates after mild foot shock. Taken together, these data suggest that Mib2 plays a critical role in synaptic plasticity and spatial memory through the Notch signaling pathway.

Notch Design for Cogging Torque Reduction of Interor type Permanent Magnet Synchronous Motor (매입형 영구자석 동기 전동기의 코깅 토크 저감을 위한 보조슬롯 설계)

  • Han, Kwang-Kyu;Ahn, Ho-Jin;Kang, Gyu-Hong;Jang, Ki-Bong;Kim, Gyu-Tak
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.6
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    • pp.959-965
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    • 2008
  • This paper presents a novel method for cogging torque reduction of interior type permanent magnet motor. For calculation position and width of notch, energy formulation and cogging torque function in air gap are analyzed by analytical method(space harmonics method) and numerical method. The optimal shape of notchs is decided by using finite element method. The validity of the proposed method is confirmed with experiments.

Optimizing Notch to reduce Cogging Torque of IPM motor (IPM 모터의 코깅토크 저감을 위한 노치 최적화)

  • Han, Kwang-Kyu;Kang, Gyu-Hong;Ahn, Young-Gyu;Lee, Dong-Yeup;Kim, Gyu-Tak
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.880-881
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    • 2007
  • By reason of variation magnetic field, cogging torque is generated. Cogging torque of IPM is bigger than other type permanent magnet motor. So, this paper presents a Optimizeing notch to reduce cogging torque of interior type permanent magnet(: IPM) motor. Through Fourier formulation of magnetic field on rotor, we found position of notch and manufactured armature that is designed by optimizing analysis. The validity of the proposed design is confirmed with experiments.

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Development of a Reporter System for In Vivo Monitoring of γ-Secretase Activity in Drosophila

  • Hong, Young Gi;Roh, Seyun;Paik, Donggi;Jeong, Sangyun
    • Molecules and Cells
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    • v.40 no.1
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    • pp.73-81
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    • 2017
  • The ${\gamma}$-secretase complex represents an evolutionarily conserved family of transmembrane aspartyl proteases that cleave numerous type-I membrane proteins, including the ${\beta}$-amyloid precursor protein (APP) and the receptor Notch. All known rare mutations in APP and the ${\gamma}$-secretase catalytic component, presenilin, which lead to increased amyloid ${\beta}$-peptide production, are responsible for early-onset familial Alzheimer's disease. ${\beta}$-amyloid protein precursor-like (APPL) is the Drosophila ortholog of human APP. Here, we created Notch- and APPL-based Drosophila reporter systems for in vivo monitoring of ${\gamma}$-secretase activity. Ectopic expression of the Notch- and APPL-based chimeric reporters in wings results in vein truncation phenotypes. Reporter-mediated vein truncation phenotypes are enhanced by the Notch gain-of-function allele and suppressed by RNAi-mediated knockdown of presenilin. Furthermore, we find that apoptosis partly contributes to the vein truncation phenotypes of the APPL-based reporter, but not to the vein truncation phenotypes of the Notch-based reporter. Taken together, these results suggest that both in vivo reporter systems provide a powerful genetic tool to identify genes that modulate ${\gamma}$-secretase activity and/or APPL metabolism.

A Study on the pressure Rising Considered Fluid inertia in the Notch Area of Balanced Type Vane Pump (노치 영역에서 유체 관성을 고려한 압력 평형형 베인 펌프의 압력 상승에 관한 연구)

  • Jo, Myeong-Rae;Han, Dong-Cheol;Mun, Ho-Ji;Park, Min-Ho;Bae, Hong-Yong
    • Tribology and Lubricants
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    • v.13 no.1
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    • pp.14-20
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    • 1997
  • This paper reports on theoretical study of the pressure overshoot in the delivery ports and pressure rising within balanced type vane pump. Pressure overshoot occur due to the accelerated fluid through the notch, so, result in pressure ripple, flow ripple, and noise. For calculating the pressure rising and fluctuations of pressure, we have modeled mathematically used continuity equation based on compressibility and momentum equation considered fluid inertia in the notch, and analyzed simultaneously. As a results of analysis, we have found oscillation of pressure and compression chamber pressure depend on the rotational speeds, notches. Using the model, notches have been shown to be important design factor in relaxing the rapid pressure rising and reducing the amplitudes of pressure overshoot.

The study on the vibration characteristic of IPM motor according to the notch design (Notch 설계에 따른 매입형영구자석형 전동기의 진동특성 고찰)

  • Lee, Seung-Hoon;Ahn, Ho-Jin;Kang, Gyu-Hong;Jang, Ki-Bong;Kim, Gyu-Tak
    • Proceedings of the KIEE Conference
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    • 2008.10c
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    • pp.47-49
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    • 2008
  • This paper presents the vibration characteristic of interior type permanent magnet (IPM) motor according to rotor design. In the design methods, the optimal notchs are put on the rotor pole face, which have an effect on variation of permanent magnet (PM) shape or residual flux density of PM. Through the space harmonics field analysis, the positions of notch are found and the optimal shapes of notch are decided by using Finite Element Method (FEM). The validity of the proposed method is confirmed with experiments. Therefore, the vibration, starting current and efficiency of IPM is measured by experiment.

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