• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.65 no.2
• /
• pp.279-285
• /
• 2016

In this paper, a cogging torque of IPM(Interior Permanent Magnet)-type BLDC motor is analyzed by FE program and the optimized notch on the rotor surface is designed to minimize the torque ripple. A differential evolution strategy algorithm and a response surface method are employed to optimize the rotor notch. In order to verify the proposed algorithm, an IPM BLDC motor is used, which is 50 kW, 8 poles, 48 slots and 1200 rpm at the rated speed. Its characteristics of the motor is calculated by FE program and 4 design variables are set on the rotor notch. The initial shape of the notch is like a non-symmetric half-elliptic and it is optimized by the developed algorithm. The cogging torque of the final model is reduced to $1.5[N{\cdot}m]$ from $5.2[N{\cdot}m]$ of the initial, which is about 71 % reduction. Consequently, the proposed algorithm for the cogging torque reduction of IPM-type BLDC motor using the rotor notch design seems to be very useful to a mechanical design for reducing noise and vibration.

• Journal of information and communication convergence engineering
• /
• v.1 no.4
• /
• pp.189-193
• /
• 2003

A new algorithm is presented for adaptive notch filtering of narrow band or sine signals for embedded among broad band noise. The notch filter is implemented as a constrained infinite impulse response filter with a minimal number of parameters, Based on the recursive prediction error (RPE) method, the algorithm has the advantages of the fast convergence, accurate results and initial estimate of filter coefficient and its covariance is revealed. A convergence criterion is also developed. By using the information of the noise-to-signal power, the algorithm can self-adjust its initial filter coefficient estimate and its covariance to ensure convergence.

• Journal of Welding and Joining
• /
• v.16 no.4
• /
• pp.73-82
• /
• 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 brdige structure. Fatigue strength ({TEX}$$\sigma$_{ult}${/TEX}) of the weldment is dependent on notch factor ({TEX}$K_{f}${/TEX}) 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. The maximum strain distribution during static loading is similar to the FEM analysis. Fatigue test of real structure was performed up to {TEX}$10^{6}${/TEX} cycles to be compared with predicted endurance limit.

• Korean Journal of Pharmacognosy
• /
• v.49 no.4
• /
• pp.285-290
• /
• 2018

Harmine, a beta-carboline alkaloid isolated from the seeds of Peganum harmala has been reported as a promising drug candidate for cancer therapy. However, the effect of harmine on breast cancer remains still unclear. In this study, the effect of harmine on the cell proliferation, migration, and invasion of breast cancer MDA-MB231 cells and the underlying mechanism were investigated. The results indicated that harmine inhibited the proliferation MDA-MB231 cells in a dose-dependent manner and markedly suppressed migration and invasion of MDA-MB231 cells. The mechanism involved in part through Notch signaling. The Notch activity was significantly inhibited by harmine treatment and harmine suppressed the expression of Jagged1 which is a key ligand to activate Notch signaling. These findings suggest a novel mechanism of harmine on anti-cancer activity and harmine may act as a potential therapeutic drug for breast cancer treatment.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.36 no.1C
• /
• pp.28-36
• /
• 2011

As Power Line has been already installed over 60% of a residential area all over the world, Broadband Service has been possible using high-speed PLC(Power Line Communication) without new access line installed for Internet access. Because of such reason, PLC is researched as the most suitable service for Last Mile Solution. But, Power Line is designed for transmitting electric power, so peripheral Wireless Communication System is affected by a leak of electric wave. In this paper, we propose a High Performance Notch Filter algorithm in comparison with a existing notch filter for reduction of interference between existing Wireless Communication Service and Power Line Service. In addition, we implement the Notch Filter emulator appling a High Performance Notch Filter and using a embedded board.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.9 no.4
• /
• pp.43-49
• /
• 2013

In this paper, it is designed inverted triangle structural planar monopole antenna with edge and rectangle slot for UWB(Ultra Wide Band) communication (3.1~10.6 GHz) and researched in about 5.8 GHz notch structure to prevent interference between UWB systems and existing wireless systems for using Wi-Fi service. The antenna have broadband property structurally through inverted triangle structural planar monopole which have edge. and rectangle form addition planned notch slot of 1 mm and height 0.1 mm. Monopole and ground of proposed antenna exist on coplanar plane, and excite as CPW. It used FR4 epoxy dielectric substrate of ${\varepsilon}r$=4.4, and the size is $20{\times}20{\times}1.6$ mm dimension. The measured results that are obtained return loss under -10 dB through 3.1~10.6 GHz(7.5 GHz) without Wi-Fi bandwidth and maximum gain of 8.44 dBi at E-plane. Radiation pattern is about the same that of dipole antenna at all frequency. And using notch slot and it will be able to confirm the quality which becomes notch from 5.8 GHz which are a radio LAN frequency range.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.16 no.1
• /
• pp.1-8
• /
• 2007

The present study examined the mechanical properties of the friction welding zone of solid and hollow shafts made with SM20C according to the depth of the notch. Friction welding was conducted at welding conditions of 2,000 rpm, friction pressure of 60MPa, friction time of 1.4 seconds, upset pressure of 100MPa, and upset time of 2.0 seconds. In the tensile strength test, the tensile strength decreased as the depth of the notch increased. Tensile strength was moderately high when the depth of the notch was 2mm. The tensile strength of the welding zone increased as the friction revolution radius increased, because the latter led to the generation of adequate friction heat. According to the hardness test, hardness likewise increased as e friction revolution radius increased. In the bending test, the bend strength of the solid shaft decreased when the depth of the notch was 0-2mm but increased when the latter was 3-5mm. With regard to the hollow shaft, the bend strength drastically decreased when the depth of the notch was 3-4mm. Upon examination it was found that the microstructure became finer when the friction revolution radius increased.

• Anatomy and Cell Biology
• /
• v.56 no.3
• /
• pp.308-312
• /
• 2023

The bony notch on the inferior border of the mandible, anterior to the attachment of the masseter muscle, where the facial vessels commonly pass, has been called different names in the literature, e.g., premasseteric notch, antegonial notch, and notch for the facial vessels. Interestingly, various disciplines have leaned toward different names for this notch. Therefore, to aid in consistent communication among professionals, the present study aimed to analyze usage of these varied terms and make recommendations for the best terminology. Based on the adjacent anatomical structures used to name this notch, three groups were analyzed in this study, a group using masseter in the term, a group using gonion in the term, and a group using facial vessels in the term. A literature search found that the group using gonion in the term was found most in the literature. The orthodontics field used gonion in the term the most (29.0%: 31/107) followed by the oral and maxillofacial surgery field (14.0%: 15/107), the plastic surgery field (4.7%: 5/107), and the anatomy field (3.7%: 4/107). The dental field used gonion in this term the most (43.9%: 47/107) and the medical field used facial vessels in the term the most (33.3%: 6/18). Based on these results, the use of gonial terms for this notch seems to be preferred.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2013.10a
• /
• pp.893-895
• /
• 2013

In this paper, we propose the planar folded monopole antenna with an inverted T-shape notch in ground plane. The proposed antenna is not only varied to a width of inner and outer patch lines to broaden bandwidth, but also it is inserted to a modified inverted T-shape notch with the same length of horizontal and vertical slit, difference of its width is about twice in the ground plane to broaden bandwidth. It is designed and simulated.

• Journal of Welding and Joining
• /
• v.7 no.4
• /
• pp.38-45
• /
• 1989

In this study, in order to evaluate the shape and the size of the plastic zone at the notch tip before stable crack growth, a newly developed technique for plastic strain measurement, that is, the recrystallization-etching technique was applied to observe the intense strain zone at the notch tip of weld HAZ. 1) The recrystallized specimens showed that the amount of the intense strain zone, more than 20% plastic zone, was quantitatively observed as the plane strain state during the growth of the plastic zone. 2) The behavior of plastic deformation at midsection are different for parent and weld HAZ. In addition, the micro crack initiation occurs at midsection, parent and weld HAZ when the crack opening displacement(COD) value is .delta.$_{t}$=0.4mm. 3) The plastic zone for parent proceeds in the forward direction at notch tip and for weld HAZ in the right and left direction at the notch tip. 4) The relation between plastic strain energy(Wp) and COD(.delta.$_{t}$) depended on yield stress, gradient and plastic strain size.ize.