• Title/Summary/Keyword: DET

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$Z_2$-VECTOR BUNDLES OVER $S^1$

  • Kim, Sung-Sook
    • Communications of the Korean Mathematical Society
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    • v.9 no.4
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    • pp.927-931
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    • 1994
  • Let G be a cyclic group of order 2 and let $S^1$ denote the unit circle in $R^2$ with the standard metric. We consider smooth G-vector bundles over $S^1$ when G acts on $S^1$ by reflection. Then the fixed point set of G on $S^1$ is two points ${z_0, z_1}$. Let $E$\mid$_{z_0} and E$\mid$_{z_1}$ be the fiber G-representation spaces at $z_0$ and $z_1$ respectively. We associate an orthogonal G-representation $\rho_i : G \to O(n)$ to $E$\mid$_{z_i}, i = 0, 1$. Let det $p\rho_i(g), g \neq 1$, be denoted by det $E$\mid$_{z_i}$ since det $\rho_i(g)$ is independent of choice of $\rho_i$.

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ON THE DETERMINANT OF A DUAL PERIODIC SINGULAR FIBER

  • Cheng Gong;Jun Lu;Sheng-Li Tan
    • Bulletin of the Korean Mathematical Society
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    • v.60 no.5
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    • pp.1365-1374
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    • 2023
  • Let F be a periodic singular fiber of genus g with dual fiber F*, and let T (resp. T*) be the set of the components of F (resp. F*) by removing one component with multiplicity one. We give a formula to compute the determinant | det T | of the intersect form of T. As a consequence, we prove that | det T | = | det T*|. As an application, we compute the Mordell-Weil group of a fibration f : S → ℙ1 of genus 2 with two singular fibers.

Vibration Modeling and Optimal Design of Differential Electromagnetic Transducer for Implantable Middle Ear Hearing Devices using the FEA (FEA를 이용한 이식형 인공중이용 차동전자 트랜스듀서의 진동 모델링과 최적 설계)

  • Kim Min-Kyu;Lim Hyung-Gyu;Han Chan-Ho;Song Byung-Seop;Park Il-Yong;Cho Jin-Ho
    • The Journal of the Acoustical Society of Korea
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    • v.24 no.7
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    • pp.379-386
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    • 2005
  • Among various kinds of hearing aids which have been developed so far. the conventional air conduction hearing aids have some problems such as the acoustic distortion, an howling effect due to acoustic feedback. Another type of hearing aid. the cochlear implant system can be applied to the profound imparied person. However. it shows the disadvantage that there is no possibility of recovery of the acoustic organ such as ossicle. On the other hand. the implantable middle ear heaving device directly vibratos the ossicular chain and has better sound qualify. good cosmetics for appearance. and wide frequency responses so that it can overcome the defects or the conventional hearing aids. In this paper, a mathematical modeling and a momentum equation derivation of the DET has been performed. For the optimization of the structure dimension generating maximal vibrating force of the DET. the computer simulation using a finite element analysis (FEA) software has been performed. Also. the vibrating transducer has been designed to make the frequency characteristics or the transducer be similar to those of the normal middle ear. Through the experimental results, the measured vibration characteristics of the DET has been evaluated to verify the performance for the application to implantable middle ear hearing devices.

Electrochemical Properties of Oxygen Adducts Pentadentate Schiff Base Cobalt (Ⅱ) Complexes in Aprotic Solvents (비수용매에서 다섯 자리 Schiff Base Cobalt (Ⅱ) 착물들의 산소 첨가 생성물에 대한 전기화학적 성질)

  • Choe, Ju Hyeong;Jeong, Jin Sun;Choe, Yong Guk;Seo, Seong Seop
    • Journal of the Korean Chemical Society
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    • v.34 no.1
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    • pp.51-62
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    • 1990
  • Pentadentate Schiff base cobalt(II) complexes; Co(II)(Sal-DET) and Co(II)(Sal-DPT) were synthesized and these complexes were allowed to react with dry to form oxygen adducts of cobalt(II) complexes such as [Co(III)(Sal-DET)]$_2O_2$ and [Co(III)(DPT)]$_2O_2$ in aprotic solvents. These complexes have been identified by IR spectra, TGA, DSC, magnetic susceptibility measurements, and elemental analysis. It has been found that the oxygen adadduct complexes of $\mu$-peroxo type have hexaccordinated octahedral configuration with pentadentate schiff base cobalt(II) and oxygen, but the mole ratio of oxygen to cobalt(III) complexes of first step for oxygen adduct formation reaction of cobalt(II) complexes in aprotic solvents are 1:1. The redox reaction processes of Co(II)(Sal-DET), Co(II)(Sal-DPT), and oxygen adduct of cobalt(II) complexes were investigated by cyclic voltammetry and DPP method with glassy carbon electrode in 0.1M TEAP-DMSO and 0.1M TEAP-pyridine. As a result the reduction reaction processes of Co(III)/Co(II) and Co(II)/Co(I) for cobalt(II) complexes and oxygen adducts of cobalt(II) complexes are two irreversible steps of one eletron process, and reaction processes of oxygen for oxygen adducts complexes were quasireversible and redox range of potential was $E_{pc}$ = -0.97V∼-0.86V and $E_{pa}$ = -0.87V ∼ 0.64V.

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POISSON BRACKETS DETERMINED BY JACOBIANS

  • Ahn, Jaehyun;Oh, Sei-Qwon;Park, Sujin
    • Journal of the Chungcheong Mathematical Society
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    • v.26 no.2
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    • pp.357-365
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    • 2013
  • Fix $n-2$ elements $h_1,{\cdots},h_{n-2}$ of the quotient field B of the polynomial algebra $\mathbb{C}[x_1,x_2,{\cdots},x_n]$. It is proved that B is a Poisson algebra with Poisson bracket defined by $\{f,g\}=det(Jac(f,g,h_1,{\cdots},h_{n-2})$ for any $f,g{\in}B$, where det(Jac) is the determinant of a Jacobian matrix.

A development of simulator for satellite power system (인공위성용 전력시스템 시뮬레이텨 개발)

  • 김영태;김희준
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.3
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    • pp.193-201
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    • 1996
  • The space power system for communication satellite which employs the direct energy transfer (DET) method consists of solar array, battry, shunt regulator, charger/discharger and power control unit (PCU). In this paper, the development of the DET power system charger/discharger unit and a microprocessor based PCU is developed for simplicity and flexiblity in the modificatin of control algorithm. A 28V bus voltage, 400W power rting power simulator is built and tested to verify the operation of the simulator at each mode and the stability of mode transition is analyzed.

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Investigation of Direct and Mediated Electron Transfer of Laccase-Based Biocathode

  • Jamshidinia, Zhila;Mashayekhimazar, Fariba;Ahmadi, Masomeh;Molaeirad, Ahmad;Alijanianzadeh, Mahdi;Janfaza, Sajad
    • Journal of Electrochemical Science and Technology
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    • v.8 no.2
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    • pp.87-95
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    • 2017
  • Enzymatic fuel cells are promising low cost, compact and flexible energy resources. The basis of enzymatic fuel cells is transfer of electron from enzyme to the electrode surface and vice versa. Electron transfer is done either by direct or mediated electron transfer (DET/MET), each one having its own advantages and disadvantages. In this study, the DET and MET of laccase-based biocathodes are compared with each other. The DET of laccase enzyme has been studied using two methods; assemble of needle-like carbon nanotubes (CNTs) on the electrode, and CNTs/Nafion polymer. MET of laccase enzyme also is done by use of ceramic electrode containing, ABTS (2,2'-azino-bis [3-ethylbenzthiazoline-6-sulphonic acid]) /sol-gel. Cyclic voltammetric results of DET showed a pair of well-defined redox peaks at $200{\mu}A$ and $170{\mu}A$ in a solution containing 5and $10{\mu}M$ o-dianisidine as a substrate for needle-like assembled CNTs and CNTs-Nafion composite respectively. In MET method using sol-gel/ABTS, the maximum redox peak was $14{\mu}A$ in the presence of 15 M solution o-dianisidine as substrate. The cyclic voltammetric results showed that laccase immobilization on needle-like assembled CNTs or CNTs-Nafion is more efficient than the sol-gel/ABTS electrode. Therefore, the expressed methods can be used to fabricate biocathode of biofuel cells or laccase based biosensors.

A Study on the Robot Vision Control Schemes of N-R and EKF Methods for Tracking the Moving Targets (이동 타겟 추적을 위한 N-R과 EKF방법의 로봇비젼제어기법에 관한 연구)

  • Hong, Sung-Mun;Jang, Wan-Shik;Kim, Jae-Meung
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.23 no.5
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    • pp.485-497
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    • 2014
  • This paper presents the robot vision control schemes based on the Newton-Raphson (N-R) and the Extended Kalman Filter (EKF) methods for the tracking of moving targets. The vision system model used in this study involves the six camera parameters. The difference is that refers to the uncertainty of the camera's orientation and focal length, and refers to the unknown relative position between the camera and the robot. Both N-R and EKF methods are employed towards the estimation of the six camera parameters. Based on the these six parameters estimated using three cameras, the robot's joint angles are computed with respect to the moving targets, using both N-R and EKF methods. The two robot vision control schemes are tested by tracking the moving target experimentally. Given the experimental results, the two robot control schemes are compared in order to evaluate their strengths and weaknesses.

A Study of the Chinese Research Trend on Effect of Erchentang utilized in the Digestive Diseases (소화기 질환에 활용된 이진탕(二陳湯)의 임상 치험례 분석 - China Academic Journal을 중심으로 -)

  • Kim, Jee-Soo;Park, Young-Bae;Park, Young-Jae
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.13 no.2
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    • pp.117-128
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    • 2009
  • Object : The purpose of this study is to reveiew recent 10 years chinese achievements on the use of digestive system on the utilization of Erchentang. Methods : From the China Journal Full Text Detabase we searched paper on the use of Erchentang by Keyword "二陳湯" Results : The researches are summarised into 7parts. (1) The Effect of Erchentang utilized in liver diseases, (2) The Effect of Erchentang utilized in constipation, (3) The Effect of Erchentang utilized in emesis, (4) The Effect of Erchentang utilized in Bile reflux gastritis, (5) The Effect of Erchentang utilized in gastroesophageal reflux disease, (6) The Effect of Erchentang utilized in gastralgia, (7) The Effect of Erchentang utilized in gastritis. Conclusion : The Effect of Erchentang's utilization has been estabalished for its usefulness in various chinese medical researches.

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AI Fire Detection & Notification System

  • Na, You-min;Hyun, Dong-hwan;Park, Do-hyun;Hwang, Se-hyun;Lee, Soo-hong
    • Journal of the Korea Society of Computer and Information
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    • v.25 no.12
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    • pp.63-71
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    • 2020
  • In this paper, we propose a fire detection technology using YOLOv3 and EfficientDet, the most reliable artificial intelligence detection algorithm recently, an alert service that simultaneously transmits four kinds of notifications: text, web, app and e-mail, and an AWS system that links fire detection and notification service. There are two types of our highly accurate fire detection algorithms; the fire detection model based on YOLOv3, which operates locally, used more than 2000 fire data and learned through data augmentation, and the EfficientDet, which operates in the cloud, has conducted transfer learning on the pretrained model. Four types of notification services were established using AWS service and FCM service; in the case of the web, app, and mail, notifications were received immediately after notification transmission, and in the case of the text messaging system through the base station, the delay time was fast enough within one second. We proved the accuracy of our fire detection technology through fire detection experiments using the fire video, and we also measured the time of fire detection and notification service to check detecting time and notification time. Our AI fire detection and notification service system in this paper is expected to be more accurate and faster than past fire detection systems, which will greatly help secure golden time in the event of fire accidents.