• 제목/요약/키워드: W-function

검색결과 2,166건 처리시간 0.031초

The Design of Iron Loss Minimization of 600W IPMSM by Quasi-newton Method (Quasi-Newton Method에 의한 600W IPMSM의 철손 최소화 설계)

  • Baek, Sung-min;Cho, Gyu-won;Kim, Gyu-tak
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • 제66권7호
    • /
    • pp.1053-1058
    • /
    • 2017
  • In this paper, the design of iron loss minimization of 600W was performed by using Quasi-Newton method. Stator shoe, the width of stator teeth and yoke, and the length of d-axis flux path were selected as design parameters, and the output characteristics according to each design variable were considered. The objective function was set to minimize iron loss. Using the Quasi-Newton method, the variables converged to the target value while changing simultaneously and multiple times. As the algorithm advanced optimization, the correlation with the behavior of each variable was compared and analyzed.

The Convolution Sum $\sum_{al+bm=n}{\sigma}(l){\sigma}(m)$ for (a, b) = (1, 28),(4, 7),(1, 14),(2, 7),(1, 7)

  • Alaca, Ayse;Alaca, Saban;Ntienjem, Ebenezer
    • Kyungpook Mathematical Journal
    • /
    • 제59권3호
    • /
    • pp.377-389
    • /
    • 2019
  • We evaluate the convolution sum $W_{a,b}(n):=\sum_{al+bm=n}{\sigma}(l){\sigma}(m)$ for (a, b) = (1, 28),(4, 7),(2, 7) for all positive integers n. We use a modular form approach. We also re-evaluate the known sums $W_{1,14}(n)$ and $W_{1,7}(n)$ with our method. We then use these evaluations to determine the number of representations of n by the octonary quadratic form $x^2_1+x^2_2+x^2_3+x^2_4+7(x^2_5+x^2_6+x^2_7+x^2_8)$. Finally we express the modular forms ${\Delta}_{4,7}(z)$, ${\Delta}_{4,14,1}(z)$ and ${\Delta}_{4,14,2}(z)$ (given in [10, 14]) as linear combinations of eta quotients.

Ion-induced secondary electron emission coefficient and work function for MgO thin film with $O_2$ plasma treatment

  • Jung, J.C.;Jeong, H.S.;Lee, J.H.;Oh, J.S.;Park, W.B.;Lim, J.Y.;Cho, J.W.;Choi, E.H.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
    • /
    • pp.525-528
    • /
    • 2004
  • The ion-induced secondary electron emission coefficient ${\gamma}$ and work function for MgO thin film with $O_2$ plasma treatment has been investigated by ${\gamma}$ -FIB (focused ion beam) system. The MgO thin film deposited from sintered material with $O_2$ plasma treatment is found to have higher ${\gamma}$ and lower work function than those without $O_2$ plasma treatment. The energy of various ions used has been ranged from 100eV to 200eV throughout this experiment. It is found that the highest secondary electron emission coefficient ${\gamma}$ has been achieved for 10 minutes of $O_2$ plasma treatment under RF power of 50W.

  • PDF

SOME PROPERTIES OF THE BEREZIN TRANSFORM IN THE BIDISC

  • Lee, Jaesung
    • Communications of the Korean Mathematical Society
    • /
    • 제32권3호
    • /
    • pp.779-787
    • /
    • 2017
  • Let m be the Lebesgue measure on ${\mathbb{C}}$ normalized to $m(D)=1,{\mu}$ be an invariant measure on D defined by $d_{\mu}(z)=(1-{\mid}z{\mid}^2)^{-2}dm(z)$. For $f{\in}L^1(D^n,m{\times}{\cdots}{\times}m)$, Bf the Berezin transform of f is defined by, $$(Bf)(z_1,{\ldots},z_n)={\displaystyle\smashmargin{2}{\int\nolimits_D}{\cdots}{\int\nolimits_D}}f({\varphi}_{z_1}(x_1),{\ldots},{\varphi}_{z_n}(x_n))dm(x_1){\cdots}dm(x_n)$$. We prove that if $f{\in}L^1(D^2,{\mu}{\times}{\mu})$ is radial and satisfies ${\int}{\int_{D^2}}fd{\mu}{\times}d{\mu}=0$, then for every bounded radial function ${\ell}$ on $D^2$ we have $$\lim_{n{\rightarrow}{\infty}}{\displaystyle\smashmargin{2}{\int\int\nolimits_{D^2}}}(B^nf)(z,w){\ell}(z,w)d{\mu}(z)d{\mu}(w)=0$$. Then, using the above property we prove n-harmonicity of bounded function which is invariant under the Berezin transform. And we show the same results for the weighted the Berezin transform in the polydisc.

Research on Correlation Method of ABS Interior Operational Noise via HILS Rig Test (HILS Rig 시험을 통한 실차 ABS 실내작동소음 예측 기법에 대한 연구)

  • Kim, Seunghwan;Yook, Jiyong;Han, Mingyu;Jeon, Namill
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 한국소음진동공학회 2013년도 추계학술대회 논문집
    • /
    • pp.483-488
    • /
    • 2013
  • The psychoacoustic quality of ABS is now considered more important than before as the focus of recent ABS function is expanded to basic function from typical emergency function. Thus, the automotive parts manufacturing companies are actively working to improve NVH (Noise, Vibration, and Harshness) in ABS module. In terms of time, test place, and cost, however, it is very inefficient to have all the operating noise validation test in real vehicle configuration especially for partially improved ABS module. To contribute to reducing the development period and to grasping the improvements faster, this research presents the study of a correlation to predict ABS operating noise inside vehicle via HILS rig test. The regression equation in this paper was statistically drawn from using Minitab S/W, and based on that equation, the noise spectrum of vehicle interior was analogized.

  • PDF

Strong Roman Domination in Grid Graphs

  • Chen, Xue-Gang;Sohn, Moo Young
    • Kyungpook Mathematical Journal
    • /
    • 제59권3호
    • /
    • pp.515-523
    • /
    • 2019
  • Consider a graph G of order n and maximum degree ${\Delta}$. Let $f:V(G){\rightarrow}\{0,1,{\cdots},{\lceil}{\frac{{\Delta}}{2}}{\rceil}+1\}$ be a function that labels the vertices of G. Let $B_0=\{v{\in}V(G):f(v)=0\}$. The function f is a strong Roman dominating function for G if every $v{\in}B_0$ has a neighbor w such that $f(w){\geq}1+{\lceil}{\frac{1}{2}}{\mid}N(w){\cap}B_0{\mid}{\rceil}$. In this paper, we study the bounds on strong Roman domination numbers of the Cartesian product $P_m{\square}P_k$ of paths $P_m$ and paths $P_k$. We compute the exact values for the strong Roman domination number of the Cartesian product $P_2{\square}P_k$ and $P_3{\square}P_k$. We also show that the strong Roman domination number of the Cartesian product $P_4{\square}P_k$ is between ${\lceil}{\frac{1}{3}}(8k-{\lfloor}{\frac{k}{8}}{\rfloor}+1){\rceil}$ and ${\lceil}{\frac{8k}{3}}{\rceil}$ for $k{\geq}8$, and that both bounds are sharp bounds.

A Study on the Software Reliability of Operational Stage S/W (운영중인 소프트웨어의 신뢰도에 관한 연구)

  • Che, Gyu-Shik
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • 제13권3호
    • /
    • pp.445-450
    • /
    • 2009
  • One method to improve quality before releasing of S/W after development is to enhance the reliability, whose direct methodology is to detect and revise fault through testing. Once the S/W is released because it meets the target reliability, the operational reliability problem arises. It is obvious the operational reliability different from that of testing stage depending on the condition whether it is universal(package) S/W or dedicated S/W. I propose the methodology to calculate operational software reliability of universal and dedicated S/W in this paper.

Network function virtualization (NFV) resource allocation (RA) scheme and research trend (네트워크기능 가상화 (NFV) 자원할당 (RA) 방식과 연구동향)

  • Kim, Hyuncheol;Yoon, Seunghyun;Jeon, Hongseok;Lee, Wonhyuk
    • Convergence Security Journal
    • /
    • 제16권7호
    • /
    • pp.159-165
    • /
    • 2016
  • Through the NFV (Network Function Virtualization), companies such as network service providers and carriers have sought to dramatically reduce CAPEX / OPEX by improving the speed of new service provisioning and flexibility of network construction through the S/W-based devices provided by NFV. One of the most important considerations for establishing an NFV network to provide dynamic services is to determine how to dynamically allocate resources (VNFs), the basic building blocks of network services, in the right place. In this paper, we analyzed the latest research trends on VNF node, link allocation, and scheduling in nodes that are required to provide arbitrary NS in NFV framework. In this paper, we also propose VNF scheduling problems that should be studied further in RA (Resource Allocation).

Effects of Invasive Low Level Laser Acupuncture Therapy(LLLAT) depending on capacity at LU7+LR5 on the Hyperlipemia Rats Induced by High Fat Diet (열결(列缺).려구에 대한 용량별 He-Ne 레이저 침 조사(照射)가 고지방(高脂肪) 식이(食餌)로 유발된 고지혈증(高脂血症) 백서(白鼠)에 미치는 영향(影響))

  • Bang, Sang-Hee;Youn, Dae-Hwan;Cho, Myung-Re;Yim, Hyun-Jin;Na, Chang-Su
    • Korean Journal of Acupuncture
    • /
    • 제23권1호
    • /
    • pp.1-14
    • /
    • 2006
  • Objectives : This research was performed to investigate the effect of invasive low level laser acupuncture therapy(LLLAT) at Yolgyol+yogu(LU7+LR5) on weight gain, food intake, food efficiency, lipid metabolism and liver function in hyperlipemia rats. Methods : Experimental groups were divided into high fat diet cup(Control group), high fat diet and 15 mW/5 min LLLAT at LU7+LR5(15 mW/5 min group), 15 mW/10 min LLLAT at LU7+LR5(15 mW/10 min group), 30 mW/5 min LLLAT at LU7+LRS(30 mW/5 min group), 30 mW/10 min LLLAT at LU7+LR5(30 mW/10 min group). LLLAT was treated at the 15,30mW-5,10min once a 2day during 5 weeks. Results : Body weight was decreased significantly in 30 mW/s min group and 30 mW/10 min group compared with control group. Food intake was decreased significantly in 15 mW/5 min group and 15 mW/10 min group compared with control group. Food efficiency was decreased significantly in 30 mW/10 min group compared with control group. In the lipid metabolism, total cholesterol, HDL-cholesterol and free fatty acid were increased significantly in 15 mW/5 min group and 30 mW/10 min group compared with control group. LDL-cholesterol was increased in 30 mW/10 min group and phospholipids was decreased significantly in all experimental group compared with control group. triglyceride was not showed significant result in all experimental group. In the liver function, AST was not showed significant result in all experimental group, ALT and ALP were increased significantly in 30 mW/10 min group, ALP was decreased in 30 mW/5 min group compared with control group. Conclusions : LLLAT at LU7 and LR5 can manage hyperlipemia by controlling body weight, food intake, food efficiency ratio and lipid metabolism.

  • PDF

Analysis of Flux Observers Using Parameter Sensitivity

  • Nam H.T.;Lee K.J.;Choi J.W.;Kim H.G.;Chun T.W.;Noh E.C.
    • Proceedings of the KIPE Conference
    • /
    • 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
    • /
    • pp.418-422
    • /
    • 2001
  • To achieve a high performance in direct vector control of induction motor, it is essential to correct estimation of rotor flux. The accuracy of flux observers for induction machines inherently depends on parameter sensitivity. This paper presents an analysis method for conventional flux observers using Parameter Sensitivity. The Parameter sensitivity is defined as the ratio of the percentage change in the system transfer function to the percentage change of the parameter variation. We define the ratio between real flux and estimated flux as the transfer function, and analyzed a parameter sensitivity of this transfer function by simulation.

  • PDF