• Title/Summary/Keyword: speed functions

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THE SINGULARITIES FOR BIHARMONIC PROBLEM WITH CORNER SINGULARITIES

  • Woo, Gyungsoo;Kim, Seokchan
    • East Asian mathematical journal
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    • v.36 no.5
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    • pp.583-591
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    • 2020
  • In [8, 9] they introduced a new finite element method for accurate numerical solutions of Poisson equations with corner singularities. They consider the Poisson equations with corner singularities, compute the finite element solutions using standard Finite Element Methods and use the extraction formula to compute the stress intensity factor(s), then they posed new PDE with a regular solution by imposing the nonhomogeneous boundary condition using the computed stress intensity factor(s), which converges with optimal speed. From the solution they could get an accurate solution just by adding the singular part. The error analysis was given in [5]. In their approaches, the singular functions and the extraction formula which give the stress intensity factor are the basic elements. In this paper we consider the biharmonic problems with the cramped and/or simply supported boundary conditions and get the singular functions and its duals and find properties of them, which are the cornerstones of the approaches of [8, 9, 10].

Prediction model for whistler chorus waves responsible for energetic electron acceleration and scattering

  • Kim, Jin-Hee;Lee, Dae-Young;Cho, Jung-Hee;Shin, Dae-Kyu
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.94.1-94.1
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    • 2013
  • Whistler mode chorus waves, which are observed outside the plasmasphere of the Earth's magnetosphere, play a major role in accelerating and scattering energetic electrons in the radiation belts. In this study we developed a predicting scheme of the global distribution of chorus by using the Time History of Events and Macroscale Interactions during Substorms (THEMIS) satellite data. First, we determined global spatial distributions of chorus activity, and identified fit functions that best represent chorus intensities in specific L-MLT zones. Second, we determined the specific dependence of average chorus intensity on preceding solar wind conditions (e.g., solar wind speed, IMF Bz, energy coupling degree) as well as preceding geomagnetic states (as represented by AE, for example). Finally, we combined these two results to develop the predicting functions for the global distribution and intensity of chorus. Implementing these results in the radiation belt models should improve the local acceleration effect by chorus waves.

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Development of Vehicle Oriented Black Box System Based on U-Healthcare and Human-Free Guard Functions

  • Lee, Dong-Myung
    • Journal of Engineering Education Research
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    • v.13 no.5
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    • pp.36-40
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    • 2010
  • The vehicle oriented block box system based on the u-healthcare and the human-free guard functions is developed in this paper. We also suggested the design philosophies, ideas, and analyzed the performance of the suggested system. The developed vehicle oriented black box system has some characteristics such as; 1) detects the dangerous situation by ultrasonic sensor in advance, and stores the situation information of the neighborhood of the vehicle to the imbedded SD memory card if the dangerous situation may be occurred in the parked vehicle; 2) detects the present location and speed information of the vehicle by GPS receiver and 3-axes acceleration sensor, and stores the information to the SD memory card periodically if the vehicle is running; 3) measures the dioxide carbon in the vehicle inside using $CO_2$ sensor, and forces the ventilation motor of the vehicle to operate and maintains the driver's health if the measured level is more than standard health requirements; 4) provides the stored vehicle's operating information to the driver by GUI (Graphical User Interface) based touch LCD monitor.

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Efficient Score Estimation and Adaptive Rank and M-estimators from Left-Truncated and Right-Censored Data

  • Chul-Ki Kim
    • Communications for Statistical Applications and Methods
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    • v.3 no.3
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    • pp.113-123
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    • 1996
  • Data-dependent (adaptive) choice of asymptotically efficient score functions for rank estimators and M-estimators of regression parameters in a linear regression model with left-truncated and right-censored data are developed herein. The locally adaptive smoothing techniques of Muller and Wang (1990) and Uzunogullari and Wang (1992) provide good estimates of the hazard function h and its derivative h' from left-truncated and right-censored data. However, since we need to estimate h'/h for the asymptotically optimal choice of score functions, the naive estimator, which is just a ratio of estimated h' and h, turns out to have a few drawbacks. An altermative method to overcome these shortcomings and also to speed up the algorithms is developed. In particular, we use a subroutine of the PPR (Projection Pursuit Regression) method coded by Friedman and Stuetzle (1981) to find the nonparametric derivative of log(h) for the problem of estimating h'/h.

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A Study on Development of Automatic Welding System by Using Multiple Welding Troches in SAW (다전극 SAW 공법을 이용한 무인 용접자동화 장치 개발에 관한 연구)

  • 정문영;김정섭;문형순;권혁준
    • Proceedings of the KWS Conference
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    • 1999.10a
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    • pp.43-46
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    • 1999
  • It has been suggested that the motivation for automation of welding processes ncludes the replacement and extension of the functions of human operators. Among these types of the welding automation, SAW(Submerged Arc Welding) was prevalently used, because it is highly suited to a wide range of application, especially for the high speed welding. A Significant portion of the total manufacturing time for a pipe fabrication process is spent on the welding following primary machining and fit-up processes. To achieve the reliable weld bead appearance, the automatic seam tracking and adaptive control to fill the groove are urgently needed. This paper proposed the mechanical functions of multi-torches welding system, flux supply and recovery system in conjunction with the complex air pulsing method and various types of methodologies. It was shown that the multi-torches welding system revealed the high welding qualities for the circular and rectangular pipes. In conclusion, the multi-torches welding system developed will contribute the advanced welding technology, welding automation and increment of the market in these areas.

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A Study on a Structure of Obstacle Detection System of AGV for Port Automation (항만 자동화를 위한 AGV 시스템의 장애물 감지 시스템의 구성에 관한 연구)

  • 박찬훈;최성락;박경택;김선호
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2000.11a
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    • pp.227-234
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    • 2000
  • AGV is very proper equipment for Port Automation. AGV must have Obstacle Detection System(ODS) for port automation. Obstacle Detection System must have some functions. It must be able to classify some specified object from background data. And it must be able to track classified objects. Finally, ODS must determine its next action for safe cruise whether it must do emergency stop or it must speed down or it must change its track. For these functions, ODS can have many different structures. In this paper, we will propose one structure among some possible ones. Our ODS has been being developed using proposed structure since last year. In this paper, we will introduce our system which is under construction.

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Structure-based Functional Discovery of Proteins: Structural Proteomics

  • Jung, Jin-Won;Lee, Weon-Tae
    • BMB Reports
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    • v.37 no.1
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    • pp.28-34
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    • 2004
  • The discovery of biochemical and cellular functions of unannotated gene products begins with a database search of proteins with structure/sequence homologues based on known genes. Very recently, a number of frontier groups in structural biology proposed a new paradigm to predict biological functions of an unknown protein on the basis of its three-dimensional structure on a genomic scale. Structural proteomics (genomics), a research area for structure-based functional discovery, aims to complete the protein-folding universe of all gene products in a cell. It would lead us to a complete understanding of a living organism from protein structure. Two major complementary experimental techniques, X-ray crystallography and NMR spectroscopy, combined with recently developed high throughput methods have played a central role in structural proteomics research; however, an integration of these methodologies together with comparative modeling and electron microscopy would speed up the goal for completing a full dictionary of protein folding space in the near future.

Fundamental restrictions for the closed-loop control of wind-loaded, slender bridges

  • Kirch, Arno;Peil, Udo
    • Wind and Structures
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    • v.12 no.5
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    • pp.457-474
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    • 2009
  • Techniques for stabilising slender bridges under wind loads are presented in this article. A mathematically consistent description of the acting aerodynamic forces is essential when investigating these ideas. Against this background, motion-induced aerodynamic forces are characterised using a linear time-invariant transfer element in terms of rational functions. With the help of these functions, the aeroelastic system can be described in the form of a linear, time-invariant state-space model. It is shown that the divergence wind speed constitutes an upper bound for the application of the selected mechanical actuators. Even active control with full state feedback cannot overcome this limitation. The results are derived and explained with methods of control theory.

Research Trend in 5G-TSN for Industrial IoT (Industrial IoT를 위한 5G-TSN 기술 동향)

  • Kim, K.S.;Kang, Y.H.;Kim, C.K.
    • Electronics and Telecommunications Trends
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    • v.35 no.5
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    • pp.43-56
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    • 2020
  • The 5G system standardization body has been developing standard functions to provide ultra-high speed, ultra-high reliability, ultra-low latency, and ultra-connected services. In 3GPP Rel-16, which was recently completed, this system has begun to develop ultra-high reliability and ultra-low latency communication functions to support the vertical industry. It is expected that the trend in the adoption of mobile communication by the vertical industry will continue with the introduction of 5G. In this paper, we present the industrial Internet-of-Things (IIoT) service scenarios and requirements for the adoption of 5G systems by the vertical industry and the related standardization trend at present. In particular, we introduce the 5G time-sensitive networking standard technology, a core technology for realizing 5G-based smart factories, for IIoT services.

High Performance Implementation of SGCM on High-End IoT Devices

  • Seo, Hwajeong
    • Journal of information and communication convergence engineering
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    • v.15 no.4
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    • pp.212-216
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    • 2017
  • In this paper, we introduce novel techniques to improve the high performance of AE functions on modern high-end IoT platforms (ARM-NEON), which support SIMD and cryptography instruction sets. For the Sophie Germain Counter Mode of operation (SGCM), counter modes of encryption and prime field multiplication are required. We chose the Montgomery multiplication for modular multiplication. We perform Montgomery multiplication in a parallel way by exploiting both the ARM and NEON instruction sets. Specifically, the NEON instruction performed 128-bit integer multiplication and the ARM instruction performed Montgomery reduction, simultaneously. This approach hides the latency for ARM in the NEON instruction set. For a high-speed counter mode of encryptions for both AE functions, we introduced two-level computations. When the tasks were large volume, we switched to the NEON instruction to execute the encryption operations. Otherwise, we performed the encryptions on the ARM module.