• Title/Summary/Keyword: typically real functions

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TYPICALLY REAL HARMONIC FUNCTIONS

  • Jun, Sook Heui
    • Korean Journal of Mathematics
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    • v.8 no.2
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    • pp.135-138
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    • 2000
  • In this paper, we study harmonic orientation-preserving univalent mappings defined on ${\Delta}=\{z:{\mid}z{\mid}>1\}$ that are typically real.

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LOGHARMONIC MAPPINGS WITH TYPICALLY REAL ANALYTIC COMPONENTS

  • AbdulHadi, Zayid;Alarifi, Najla M.;Ali, Rosihan M.
    • Bulletin of the Korean Mathematical Society
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    • v.55 no.6
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    • pp.1783-1789
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    • 2018
  • This paper treats the class of normalized logharmonic mappings $f(z)=zh(z){\overline{g(z)}}$ in the unit disk satisfying ${\varphi}(z)=zh(z)g(z)$ is analytically typically real. Every such mapping f admits an integral representation in terms of its second dilatation function and a function of positive real part with real coefficients. The radius of starlikeness and an upper estimate for arclength are obtained. Additionally, it is shown that f maps the unit disk into a domain symmetric with respect to the real axis when its second dilatation has real coefficients.

Convex hulls and extreme points of families of symmetric univalent functions

  • Hwang, J.S.
    • Bulletin of the Korean Mathematical Society
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    • v.33 no.1
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    • pp.1-16
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    • 1996
  • Earlier in 1935[12], M. S. Robertson introduced the class of quadrant preserving functions. More precisely, let Q be the class of all functions f(z) analytic in the unit disk $D = {z : $\mid$z$\mid$ < 1}$ such that f(0) = 0, f'(0) = 1, and the range f(z) is in the j-th quadrant whenever z is in the j-th quadrant of D, j = 1,2,3,4. This class Q contains the subclass of normalized, odd univalent functions which have real coefficients. On the other hand, this class Q is contained in the class T of odd typically real functions which was introduced by W. Rogosinski [13]. Clearly, if $f \in Q$, then f(z) is real when z is real and therefore the coefficients of f are all real. Recently, it was observed by Y. Abu-Muhanna and T. H. MacGregor [1] that any function $f \in Q$ is odd. Instead of functions "preserving quadrants", the authors [1] have introduced the notion of "preserving sectors".

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ON A COEFFICIENT PROBLEM OF ANALYTIC SYMMETRIC FUNCTIONS

  • Hwang, J.S.
    • Bulletin of the Korean Mathematical Society
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    • v.23 no.2
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    • pp.161-166
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    • 1986
  • Through the paper, we consider functions f analytic in the unit disk D={z:vertical bar z vertical bar <1} normalized by f(0)=0 and f'(0)=1. Following Rogosinski [5], we let T denote the class of all typically-real functions f which preserve half-plane in the following sense.

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ON INTEGRAL MEANS OF DERIVATIVES OF UNIVALENT FUNCTIONS

  • Elhosh, M.M.
    • Bulletin of the Korean Mathematical Society
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    • v.24 no.1
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    • pp.13-17
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    • 1987
  • Let S denote the class of nivalent functions normalized so that f(0)=f'(0)-1=0 in vertical bar z vertical bar <1. Let $S_{\alpha}$$^{*}$, -.pi./2<.alpha.<.pi./2, denote the subclass of S that satisfies Re $e^{i{\alpha}}$zf'(z)/f(z).geq.0 in vertical bar z vertical bar <1; then f is called .alpha.-spiral-like and the case .alpha.=0 is the class of normalized starlike functions [6, pp.52]. Let T denote the class of functions f normalized as above and satisfying Im z[Im f(z)]..geq.0 in vertical bar z vertical bar <1; then f is called typically real and T contains those functions of S whose coefficients are real [6, pp.55]. Also, in view of [6, pp.231], let B(.lambda.) be the class of function normalized as above and map vertical bar z vertical bar <1 onto the complement of an arc with radial angle .lambda.(0<.lambda.<.pi./2). The radial angle is meant to be the angle between the tangent and radial vectors to the arc. This note includes a sharp version for Corollary 1 of [2] when f.mem. $S_{\alpha}$$^{*}$ as well as a logarithmic coefficient estimate.nt estimate.

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A Study on Real-time Graphic Workflow For Achieving The Photorealistic Virtual Influencer

  • Haitao Jiang
    • International journal of advanced smart convergence
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    • v.12 no.1
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    • pp.130-139
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    • 2023
  • With the increasing popularity of computer-generated virtual influencers, the trend is rising especially on social media. Famous virtual influencer characters Lil Miquela and Imma were all created by CGI graphics workflows. The process is typically a linear affair. Iteration is challenging and costly. Development efforts are frequently siloed off from one another. Moreover, it does not provide a real-time interactive experience. In the previous study, a real-time graphic workflow was proposed for the Digital Actor Hologram project while the output graphic quality is less than the results obtained from the CGI graphic workflow. Therefore, a real-time engine graphic workflow for Virtual Influencers is proposed in this paper to facilitate the creation of real-time interactive functions and realistic graphic quality. The real-time graphic workflow is obtained from four processes: Facial Modeling, Facial Texture, Material Shader, and Look-Development. The analysis of performance with real-time graphical workflow for Digital Actor Hologram demonstrates the usefulness of this research result. Our research will be efficient in producing virtual influencers.

Density distributions and Power spectra of outflow-driven turbulence

  • Kim, Jongsoo;Moraghan, Anthony
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.57.2-57.2
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    • 2014
  • Protostellar jets and outflows are signatures of star formation and promising mechanisms for driving supersonic turbulence in molecular clouds. We quantify outflow-driven turbulence through three-dimensional numerical simulations using an isothermal version of the total variation diminishing code. We drive turbulence in real space using a simplified spherical outflow model, analyze the data through density probability distribution functions (PDFs), and investigate density and velocity power spectra. The real-space turbulence-driving method produces a negatively skewed density PDF possessing an enhanced tail on the low-density side. It deviates from the log-normal distributions typically obtained from Fourier-space turbulence driving at low densities, but can provide a good fit at high densities, particularly in terms of mass-weighted rather than volume-weighted density PDF. We find shallow density power-spectra of -1.2. It is attributed to spherical shocks of outflows themselves or shocks formed by the interaction of outflows. The total velocity power-spectrum is found to be -2.0, representative of the shock dominated Burger's turbulence model. Our density weighted velocity power spectrum is measured as -1.6, slightly less that the Kolmogorov scaling values found in previous works.

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Development of Processor Real-Time Monitoring Software for Drone Flight Control Computer Based on NUTTX (NUTTX 기반 드론 비행조종컴퓨터의 통합시험을 위한 프로세서 모니터링 연구)

  • Choi Jinwon
    • Journal of Platform Technology
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    • v.10 no.4
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    • pp.62-69
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    • 2022
  • Flight control systems installed on unmanned aircraft require thorough verification from the design stage. This verification is made through the integrated flight control test environment. Typically, a debugger is used to monitor the internal state of a flight control computer in real time. Emulator with a real-time memory monitor and trace is relatively expensive. The JTAG Emulator is unable to operate in real time and has limitations that cannot be caught up with the processing speed of latest high-speed processors. In this paper, we describe the results of the development of internal monitoring software for drone flight control computer processors based on NUTTX/PIXHAWK. The results of this study show that the functions provided compared to commercial debugger are limited, but it can be sufficiently used to verify the flight control system using this system under limited budget.

Development of Simulator for Hierarchical Battery Management System (계층적 배터리 관리 시스템 시뮬레이션 기술 개발)

  • Kang, Hyunwoo;Ahn, SungHo;Kim, Dongkyun
    • IEMEK Journal of Embedded Systems and Applications
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    • v.8 no.4
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    • pp.213-218
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    • 2013
  • In this research, we report on the development of simulation system for performance verification of BMS(Battery Management System) which is utilized in electric vehicles. In the industrial circles, a manufacturer of BMS typically tests their system with real battery packs. However, it takes a long time to test all functions of BMS. Here, we develop BMU(Battery Managament Unit) as an embedded board, which will be installed in electric vehicle for controlling battery packs. All other environment factors for testing BMU are developed in softwares in order to reduce the term of test. Especially, the proposed system consists of cell simulator and CMU(Cell Management Unit) simulator which simulate real battery cells and control battery cells. These simulators enable the BMU to test more battery cells. In addition, proposed system provides diagnosis program in order to diagnose and monitor the condition of BMS which makes the test of BMS more easily. In order to verify the performance of the developed simulator, we have performed the experiment with real battery packs and our simulator. Through comparing two results of experiments, we verify that developed simulator shows better performance in terms of less amount of testing duration though having high reliability.

Functions and Driving Mechanisms for Face Robot Buddy (얼굴로봇 Buddy의 기능 및 구동 메커니즘)

  • Oh, Kyung-Geune;Jang, Myong-Soo;Kim, Seung-Jong;Park, Shin-Suk
    • The Journal of Korea Robotics Society
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    • v.3 no.4
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    • pp.270-277
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    • 2008
  • The development of a face robot basically targets very natural human-robot interaction (HRI), especially emotional interaction. So does a face robot introduced in this paper, named Buddy. Since Buddy was developed for a mobile service robot, it doesn't have a living-being like face such as human's or animal's, but a typically robot-like face with hard skin, which maybe suitable for mass production. Besides, its structure and mechanism should be simple and its production cost also should be low enough. This paper introduces the mechanisms and functions of mobile face robot named Buddy which can take on natural and precise facial expressions and make dynamic gestures driven by one laptop PC. Buddy also can perform lip-sync, eye-contact, face-tracking for lifelike interaction. By adopting a customized emotional reaction decision model, Buddy can create own personality, emotion and motive using various sensor data input. Based on this model, Buddy can interact probably with users and perform real-time learning using personality factors. The interaction performance of Buddy is successfully demonstrated by experiments and simulations.

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