• Title/Summary/Keyword: simultaneous-source

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A Study on the Performance Improvement of a Simultaneous Heating and Cooling Water Source Heat Pump System by Controlling of the Refrigerant Flow Rate in an Outdoor Unit (수열원 냉난방 동시형 히트펌프 시스템의 실외 열교환기 유량제어를 통한 성능개선에 관한 연구)

  • Bae, Heung Hee;Lee, Dong Hyuk;Lee, Sanghun;Kim, Byengsoon;Ahn, Young Chull
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.25 no.3
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    • pp.131-136
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    • 2013
  • The present study has conducted cycle design and control technology of a water source VRF heat pump system. Previously, study of a simultaneous heating and cooling in an air source VRF heat pump system has been conducted. However, performance data and design methods for simultaneous heating and cooling in a water source VRF heat pump system are limited in the literature, due to various system parameters and operating conditions. In this study, the operating characteristics and performances of a simultaneous heating and cooling heat pump system are carried out, in simultaneous operation modes. Control logics of an EEV are developed for flow rate control to the outdoor unit, and are verified. When the control logics are applied, the simultaneous cooling and heating performances are sufficiently achieved, and system COPs are increased by up to 23.4%.

Perspective Coherence in Simultaneous Interpreting - with Reference to German-Korean Interpreting - (동시통역과 시각적 응집성 - 독한 통역을 중심으로 -)

  • Ahn In-Kyoung
    • Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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    • v.9
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    • pp.169-193
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    • 2004
  • In simultaneous interpreting, if the syntactic structure of the source language and the target language are very different, interpreters have to wait before being able to reformulate the source text segments into a meaningful utterance in target language. It is inevitable to adapt the target language structure to that of the source language so as not to unduly increase the memory load and to minimize the pause. While such adaptation enables simultaneous interpretating, it results in damaging the perspective coherence of the text. Discovering when such perspective coherence is impaired, and how the problem can be relieved, will enable interpreters to enhance their performance. This paper analyses the reasons for perspective coherence damage by looking at some examples of German-Korean simultaneous interpreting.

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Simultaneous neural machine translation with a reinforced attention mechanism

  • Lee, YoHan;Shin, JongHun;Kim, YoungKil
    • ETRI Journal
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    • v.43 no.5
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    • pp.775-786
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    • 2021
  • To translate in real time, a simultaneous translation system should determine when to stop reading source tokens and generate target tokens corresponding to a partial source sentence read up to that point. However, conventional attention-based neural machine translation (NMT) models cannot produce translations with adequate latency in online scenarios because they wait until a source sentence is completed to compute alignment between the source and target tokens. To address this issue, we propose a reinforced learning (RL)-based attention mechanism, the reinforced attention mechanism, which allows a neural translation model to jointly train the stopping criterion and a partial translation model. The proposed attention mechanism comprises two modules, one to ensure translation quality and the other to address latency. Different from previous RL-based simultaneous translation systems, which learn the stopping criterion from a fixed NMT model, the modules can be trained jointly with a novel reward function. In our experiments, the proposed model has better translation quality and comparable latency compared to previous models.

Simultaneous Measurements of Drain-to-Source Current and Carrier Injection Properties of Organic Thin-Film Transistors

  • Majima, Yutaka
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08a
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    • pp.271-272
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    • 2007
  • Displacement current $(I_{dis})$ and drain-to-source current $(I_{DS})$ are evaluated using the simultaneous measurements of source $(I_S)$ and drain $(I_D)$ currents during the application of a constant drain voltage and a triangular-wave gate voltage $(V_{GS})$ to top-contact pentacene thin-film transistors.

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A Study on Optimization of the Global-Correlation-Based Objective Function for the Simultaneous-Source Full Waveform Inversion with Streamer-Type Data (스트리머 방식 탐사 자료의 동시 송신원 전파형 역산을 위한 Global correlation 기반 목적함수 최적화 연구)

  • Son, Woo-Hyun;Pyun, Suk-Joon;Jang, Dong-Hyuk;Park, Yun-Hui
    • Geophysics and Geophysical Exploration
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    • v.15 no.3
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    • pp.129-135
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    • 2012
  • The simultaneous-source full waveform inversion improves the applicability of full waveform inversion by reducing the computational cost. Since this technique adopts simultaneous multi-source for forward modeling, unwanted events remain in the residual seismograms when the receiver geometry of field acquisition is different from that of numerical modeling. As a result, these events impede the convergence of the full waveform inversion. In particular, the streamer-type data with limited offsets is the most difficult data to apply the simultaneous-source technique. To overcome this problem, the global-correlation-based objective function was suggested and it was successfully applied to the simultaneous-source full waveform inversion in time domain. However, this method distorts residual wavefields due to the modified objective function and has a negative influence on the inversion result. In addition, this method has not been applied to the frequency-domain simultaneous-source full waveform inversion. In this paper, we apply a timedamping function to the observed and modeled data, which are used to compute global correlation, to minimize the distortion of residual wavefields. Since the damped wavefields optimize the performance of the global correlation, it mitigates the distortion of the residual wavefields and improves the inversion result. Our algorithm incorporates the globalcorrelation-based full waveform inversion into the frequency domain by back-propagating the time-domain residual wavefields in the frequency domain. Through the numerical examples using the streamer-type data, we show that our inversion algorithm better describes the velocity structure than the conventional global correlation approach does.

Evaluate the usefulness of Coincidence Summing Correction Factors for Cylinder and Extended Source Penelope Simulation (실린더 및 확장 소스 PENELOPE 시뮬레이션에 대한 동시합성보정 계수 유용성 평가)

  • Jang, Eun-Sung;Chang, Bo-Seok
    • Journal of the Korean Society of Radiology
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    • v.15 no.6
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    • pp.821-831
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    • 2021
  • In order to calibrate energy and efficiency using the PENELOPE Code, a PENELOPE simulation was performed using a volume source. Here, we want to verify peak efficiency and usefulness by performing simultaneous measurement and correction. calculate the coincident sum correction for all volumes, first subdivide the volumes of the cylinder and the four Marinelli beakers into three heights again. Therefore, the simultaneous measurement correction coefficient in three areas and the simultaneous measurement correction coefficient for the entire volume source are calculated as output. At low energies, the j value for each source volume (50-300 ml) is small and increases significantly in the high energy range. Simulation results showed good agreement within 2.5% for all source volumes except for 50 ml and 300 ml, which were up to 4%. This means that the correction for the simultaneous measurement effect during measurement is effective. In addition. Based on this, it can be confirmed that there is an advantage to improve the detection efficiency when measuring various sources and environmental samples.

Experimental Investigation of Physical Mechanism for Asymmetrical Degradation in Amorphous InGaZnO Thin-film Transistors under Simultaneous Gate and Drain Bias Stresses

  • Jeong, Chan-Yong;Kim, Hee-Joong;Lee, Jeong-Hwan;Kwon, Hyuck-In
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.17 no.2
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    • pp.239-244
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    • 2017
  • We experimentally investigate the physical mechanism for asymmetrical degradation in amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors (TFTs) under simultaneous gate and drain bias stresses. The transfer curves exhibit an asymmetrical negative shift after the application of gate-to-source ($V_{GS}$) and drain-to-source ($V_{DS}$) bias stresses of ($V_{GS}=24V$, $V_{DS}=15.9V$) and ($V_{GS}=22V$, $V_{DS}=20V$), but the asymmetrical degradation is more significant after the bias stress ($V_{GS}$, $V_{DS}$) of (22 V, 20 V) nevertheless the vertical electric field at the source is higher under the bias stress ($V_{GS}$, $V_{DS}$) of (24 V, 15.9 V) than (22 V, 20 V). By using the modified external load resistance method, we extract the source contact resistance ($R_S$) and the voltage drop at $R_S$ ($V_{S,\;drop}$) in the fabricated a-IGZO TFT under both bias stresses. A significantly higher RS and $V_{S,\;drop}$ are extracted under the bias stress ($V_{GS}$, $V_{DS}$) of (22 V, 20V) than (24 V, 15.9 V), which implies that the high horizontal electric field across the source contact due to the large voltage drop at the reverse biased Schottky junction is the dominant physical mechanism causing the asymmetrical degradation of a-IGZO TFTs under simultaneous gate and drain bias stresses.

Quench characteristics of YBCO thin films using magnetic field source for superconducting fault current limiters

  • Lee, B.W.;Park, K.B.;Kang, J.S.;Oh, I.S.
    • Progress in Superconductivity and Cryogenics
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    • v.6 no.2
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    • pp.11-14
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    • 2004
  • YBCO thin films have good characteristics for current limiting materials due to compact size and high current carrying capability. But the irregularities and the extreme thin thickness of YBCO films cause some difficulties in simultaneous quench and thermal shock protection. In order to solve these problems, vertical magnetic field generated from solenoid coil was applied to the YBCO element. And also to minimize the inductance caused by the serial connection of magnetic field source with superconducting elements, magnetic field source was separated from the power lines adapting protective current transformer. In this study, electric field-current (E-I) and quench characteristics of YBCO films were analyzed both by electrical measuring method and observations of bubble propagation. From the experiment results, it was revealed that the magnetic fields generated by surrounding coil could induce the uniform quench distribution for all stripes of current limiting units and finally simultaneous quenches were realized in all serial connection of YBCO elements. In addition, the separation of magnetic field source form electrical network could be good solution for simultaneous quench of YBCO films without any unnecessary effect caused by serial connection.

Line-Source Scattering from Slant Strips

  • Ock, Jang-Soo;Eom, Hyo-Joon
    • Journal of electromagnetic engineering and science
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    • v.9 no.4
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    • pp.229-231
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    • 2009
  • Electromagnetic scattering from slant strips excited by a line source is investigated. Boundary conditions are applied to obtain simultaneous equations for discrete modal coefficients. Computations are performed to illustrate the effects of line-source scattering on radiation patterns.

Simultaneous observations of the H2O and SiO masers toward the late-type stars using KVN

  • Yun, Youngjoo;Cho, Se-Hyung;Kim, Jaeheon;Choi, Yoon Kyung
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.1
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    • pp.59.2-59.2
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    • 2015
  • We present the results of simultaneous observations of the H2O and SiO masers emitted from the circumstellar envelopes of the late-type stars. These observations have been carried out at the K and Q bands using KVN since 2014 August and were scheduled to test the feasibility of multi-frequency phase referencing analysis on the maser lines. In order to increase the accuracy of group delay solution in the fringe search on the continuum source, the IF channels were randomly distributed within the available bandwidth of 500 MHz in each band. The positions of all maser spots are relatively described with respect to the position of the reference continuum source through the source frequency phase referencing technique, and this provides the astrometric position accuracy. Therefore, the relative locations of the H2O maser spots with respect to the SiO maser spots are determined from our observations, and the capability of the simultaneous multi-band observation of KVN is proved to be powerful to study the maser pumping mechanism around the late-type stars.

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