• Title/Summary/Keyword: Q&A System

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불확실한 환경 하에서의 정량발주 시스템

  • Choe Seong Hui;Yang Gwang Mo;Park Jae Hyeon;Gang Gyeong Sik
    • Proceedings of the Safety Management and Science Conference
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    • 2004.11a
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    • pp.447-451
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    • 2004
  • Generally, Fixed Quantity ordering system (Q-system) uses linear model in inventory decrease. This paper focuses on that Fixed Quantity ordering system (Q-system) is based on a continuous review system. To use a continuous review system is because of an inventory decrease ration is not constant. Therefore, this paper introduces a method to select a model which is proper to virtual data under conditions which are inconstant.

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Tracking Performance Improvement for Optical Disk Drive Using Error-based Modified Disturbance Observer (오차 기반의 수정된 외란 관측기를 이용한 광디스크 드라이브의 트랙 추종 성능 향상)

  • Kim Hong-Rok;Choi Young-Jin;Suh Il-Hong;Chung Wan-Kyun
    • Journal of Institute of Control, Robotics and Systems
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    • v.12 no.7
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    • pp.637-643
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    • 2006
  • Generally, the tracking performance of optical disk drive(ODD) system can be improved using a disturbance observer(DOB). However, a DOB is not easily applied in an ODD system because an additional microprocessor, such as a digital signal processor(DSP), is needed. This paper shows how a DOB system can be replaced by the error-based modified disturbance observer(EM-DOB) when two mathematical conditions are satisfied. Due to the simplified structure of EM-DOB, the algorithm is easily implemented as an analog circuit, which is suitable for the ODD servo system. Additionally, in these algorithms, disturbances rejection performances can be tuned as Q filter parameters. Similar to a DOB system, three design guidelines of a Q filter can be applied. Experimental results of DOB and EM-DOB are evaluated under forced disturbances.

Application of Software Quality Model and Metric for Software Product Assurance for KASS Control Station (KASS 통합운영국 소프트웨어 품질 보증을 위한 소프트웨어 품질 모델 및 메트릭 적용방안)

  • Kim, Youn-sil;Lee, Eun-sung
    • Journal of Advanced Navigation Technology
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    • v.24 no.1
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    • pp.28-36
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    • 2020
  • Korea augmentation satellite system (KASS) is the Korean satellite based augmentation system (SBAS) developed by ministry of land, infrastructure, and transport (MOLIT) since 2014. Since KASS is the safety critical system that can affect to the safety of airplane, the software of KASS is developed according to the DO178B software level induced from safety analysis. In case of KASS control station (KCS), most of the software of KCS get assigned software level E in DO178B. In that case, ECSS-Q-ST-80C category D is assigned as a software product assurance standard. In this paper, the software related standard ECSS-E-ST-40C, ECSS-Q-HB-80-04A are analyzed to satisfy ECSS-Q-ST-80C and as a result the software product assurance activities regarding software life cycle and the software quality model, metric is proposed for the product assurance of the KCS software.

Adaptive Slot-Count Selection Algorithm based on Tag Replies in EPCglobal Gen-2 RFID System

  • Lim, In-Taek
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2011.10a
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    • pp.653-655
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    • 2011
  • EPCglobal proposed a Q-algorithm, which is used for selecting a slot-count in the next query round. However, it is impossible to allocate an optimized slot-count because the original Q-algorithm did not define an optimized weight C value. In this paper, we propose an adaptive Q-algorithm, in which we differentiate the weight values with respect to collision and empty slots. The weight values are defined with the identification time as well as the collision probability.

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Development of Torque Monitoring System of Induction Spindle Motor using Graphic-programming (Graphic-programming 을 이용한 주축용 유도전동기의 토크감시시스템 개발)

  • Lee, In-Hwan;Kwon, Won-Tae
    • Journal of the Korean Society for Precision Engineering
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    • v.18 no.10
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    • pp.184-193
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    • 2001
  • In vector control technique, stator currents of an induction motor are transformed to equivalent d-q currents in a reference frame consist of d and q axis, each of which is coincide with flux and torque direction respectively. Since the current in q-axis is related to the torque in a synchronously rotating frame, torque is estimated as a function of q-axis current and flux. In this paper, a method to estimate torque of an induction motor based on the measurement of 3-phase currents and rotating velocity of a rotor is presented. Graphic-programming is used to measure signals, to estimate the torque and to show the result in the form of user friendly graph in window environment. To stabilize the fluctuation of estimated torque caused from the small measurement error of the rotor velocity, the stator current is reconstructed in a program based on measured signals. The experimental results executed under the velocity of 500 rpm, 1500 rpm without load and 1500 rpm with load show that the proposed method estimates the torque very well.

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Seamless Transition Strategy for Wide Speed-Range Sensorless IPMSM Drives with a Virtual Q-axis Inductance

  • Shen, Hanlin;Xu, Jinbang;Yu, Baiqiang;Tang, Qipeng;Chen, Bao;Lou, Chun;Qiao, Yu
    • Journal of Power Electronics
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    • v.19 no.5
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    • pp.1224-1234
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    • 2019
  • Hybrid rotor position estimation methods that integrate a fundamental model and high frequency (HF) signal injection are widely used for the wide speed-range sensorless control of interior permanent-magnet synchronous machines (IPMSMs). However, the direct transition of two different schemes may lead to system fluctuations or system instability since two estimated rotor positions based on two different schemes are always unequal due to the effects of parameter variations, system delays and inverter nonlinearities. In order to avoid these problems, a seamless transition strategy to define and construct a virtual q-axis inductance is proposed in this paper. With the proposed seamless transition strategy, an estimated rotor position based on a fundamental model is forced to track that based on HF signal injection before the transition by adjusting the constructed virtual q-axis inductance. Meanwhile, considering that the virtual q-axis inductance changes with rotor position estimation errors, a new observer with a two-phase phase-locked loop (TP-PLL) is developed to accurately obtain the virtual q-axis inductance online. Furthermore, IPMSM sensorless control with maximum torque per ampere (MTPA) operations can be tracked automatically by selecting the proper virtual q-axis inductance. Finally, experimental results obtained from an IPMSM demonstrate the feasibility of the proposed seamless transition strategy.

Safety, High Quality, Confidence of Kaneka CoQ10

  • Fujii, Kenji
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2006.11a
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    • pp.139-145
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    • 2006
  • Kaneka Corporation (Kaneka) has been manufacturing CoQ10 under GMP regulation since 1977. Kaneka has a sophisticated quality control system and has been supplying high quality CoQ10 materials to the worldwide customers (Kaneka CoQ10) for about 30 years. Kaneka CoQ10 is characterized by a lot of safety data, which are derived from clinical trials with healthy volunteers (single-dose and 4-week multi-dose safety studies), animal studies (13-week sub-chronic study in dogs and 52-week chronic study in rats), three types of mutagenicity test, six type of skin irritation test (for cosmetics), and others. The risk assessment of CoQ10 was performed by Council for Responsible Nutrition (USA). They reviewed many of available clinical data including clinical trials using Kaneka Q10, and concluded that the upper level for supplements (ULS) of CoQ10 is 1,200 mg/day (Hathcock and Shao. 2006, Regulatory Toxicology and Pharmacology, 45, 282 - 288).

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Safety, High Quality, Confidence of Kaneka CoQ10

  • Fujii, Kenji
    • 한국약용작물학회:학술대회논문집
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    • 2006.11a
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    • pp.139-145
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    • 2006
  • Kaneka Corporation (Kaneka) has been manufacturing CoQ10 under GMP regulation since 1977. Kaneka has a sophisticated quality control system and has been supplying high quality CoQ10 materials to the worldwide customers (Kaneka CoQ10) for about 30 years. Kaneka CoQ10 is characterized by a lot of safety data, which are derived from clinical trials with healthy volunteers (single-dose and 4-week multi-dose safety studies), animal studies (13-week sub-chronic study in dogs and 52-week chronic study in rats), three types of mutagenicity test, six type of skin irritation test (for cosmetics), and others. The risk assessment of CoQ10 was performed by Council for Responsible Nutrition (USA). They reviewed many of available clinical data including clinical trials using Kaneka Q10, and concluded that the upper level for supplements (ULS) of CoQ10 is 1,200mg/day (Hathcock and Shao. 2006, Regulatory Toxicology and Pharmacology, $\underline{45}$, 282 - 288).

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The Initial Irreversible Capacity of the First Doping/Undoping of Lithium into Carbon

  • Doh, Chil-Hoon;Kim, Hyun-Soo;Moon, Seong-In
    • Carbon letters
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    • v.1 no.3_4
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    • pp.148-153
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    • 2001
  • The initial irreversible capacity, $Q_i$, is one of the parameters to express the material balancing of the cathode to anode. We introduced new terms, which are the initial intercalation Ah efficiency (IIE) and the initial irreversible specific capacity at the surface ($Q_{is}$), to express precisely the irreversibility of an electrode/electrolyte system. Two terms depended on kinds of active-materials and compositions of the electrode, but did not change with charging state. MPCF had the highest value of IIE and the lowest value of $Q_{is}$ in 1M $LiPE_6$/EC + DEC (1 : 1 volume ratio) electrolyte. IIE value of $LiCoO_2$ electrode was 97-98%, although the preparation condition of the material and the electrolyte were different. $Q_{is}$ value of $LiCoO_2$ was 0~1 mAh/g. MPCF-$LiCoO_2$ cell system had the lowest of the latent capacity. $Q_{is}$ value increased slightly by adding conductive material. IIE and $Q_{is}$ value varied with the electrolyte. By introducing PC to EC+DEC mixed solvent, IIE values were retained, but $Q_{is}$ increased. In case of addition of MP, IIE value increased and $Q_{is}$ value also increased a little.

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A Series of IncQ-Based Reporter Plasmids for Use in a Range of Gram-Negative Genera

  • O'Sullivan, Laura E.;Nickerson, Cheryl A.;Wilson, James W.
    • Journal of Microbiology and Biotechnology
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    • v.20 no.5
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    • pp.871-874
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    • 2010
  • Many studies require expression analysis of the same gene/promoter across a range of bacterial genera. However, there is currently a lack of availability of reporters based on the broad-host-range IncQ replicon, which is compatible with a popular improved IncP transfer system that is self-transfer defective. We report IncQ lacZ reporter plasmids with features including (1) compatibility with IncP, IncW, and pBHR/pBBR replicons, (2) a variety of antibiotic markers (Sp-r, Sm-r, Km-r, Cm-r), (3) convenient mobilization via a novel self-transfer-defective IncP conjugation system, and (4) GenBank DNA sequences. Utility is demonstrated using three different promoters in different Gram-negative genera.