• Title/Summary/Keyword: Compensation current

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Improved instantaneous Following Control Function for High Power Factor PWM Matrix Converter (고역율 PWM 매트릭스 컨버터의 개선된 순시추종 제어함수)

  • Kim, Kwang-Tae
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.19 no.3
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    • pp.35-43
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    • 2005
  • Matrix converters have been studied for eliminating dc link of conventional converter-inverter system, and various undulation strategy have been proposed. Therefore, matrix converter have no energy storage component except for small ac later for the elimination of switching ripple, and can be made compact and highly reliable compare with the do link inverter system. Matrix converter, however, directly connected the input and the output terminals by bidirectional static switch. As a result if the input voltage are asymmetrical, and contain harmonics, the influence of the distortions directly appear on the output terminal. This problem is a major obstacle to the matrix converter. A new control method using average comparison strategy have been proposed in this paper. This control method realizes sinusoidal input and output current unity input displacement factor regardless of load power factor. Moreover, compensation of the asymmetrical and/or harmonic containing input voltage is automatically realized, and calculation time of control function is reduced.

Motion vector-tracing algorithms of video sequence (비디오 시퀀스의 움직임 추적 알고리즘)

  • 이재현
    • Journal of the Korea Computer Industry Society
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    • v.3 no.7
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    • pp.927-936
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    • 2002
  • This paper presents the extraction of a feature by motion vector for efficient content-based retrieval for digital video. in this paper, divided by general size block for the current frame by video, using BMA(block matching algorithm) for an estimate by block move based on a time frame. but in case BMA appeared on a different pattern fact of motion in the vector obtain for the BMA. solve in this a problem to application for full search method this method is detected by of on many calculations. I propose an alternative plan in this paper Limit the search region to $\pm$15 and search is a limit integer pixel. a result, in this paper is make an estimate motion vector in more accurately using motion vector in adjoin in blocks. however, refer to the block vector because occurrence synchronism. Such addition information is get hold burden receive to transmit therefore, forecasted that motion feature each block and consider for problems for establish search region. in this paper Algorithm based to an examination Motion Estimation method by for motion Compensation is proposed.

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Estimation of Weld Bead Shape and the Compensation of Welding Parameters using a hybrid intelligent System (하이브리드 지능시스템을 이용한 용접 파라메타 보상과 용접형상 평가에 관한 연구)

  • Kim Gwan-Hyung;Kang Sung-In
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.6
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    • pp.1379-1386
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    • 2005
  • For efficient welding it is necessary to maintain stability of the welding process and control the shape of the welding bead. The welding quality can be controlled by monitoring important parameters, such as, the Arc Voltage, Welding Current and Welding Speed during the welding process. Welding systems use either a vision sensor or an Arc sensor, both of which are unable to control these parameters directly. Therefore, it is difficult to obtain necessary bead geometry without automatically controlling the welding parameters through the sensors. In this paper we propose a novel approach using fuzzy logic and neural networks for improving welding qualify and maintaining the desired weld bead shape. Through experiments we demonstrate that the proposed system can be used for real welding processes. The results demonstrate that the system can efficiently estimate the weld bead shape and remove the welding detects.

Neutral-Point Voltage Ripple Reduction of High Frequency Injection Sensorless Control of IPMSM Fed by a Three-Level Inverter (3레벨 인버터로 구동되는 IPMSM의 고주파 주입 센서리스 운전에서 중성점 전압 리플 저감)

  • Cho, Dae-Hyun;Kim, Seok-Min;Lee, Kyo-Beum
    • Journal of IKEEE
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    • v.24 no.3
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    • pp.867-876
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    • 2020
  • This paper proposes a neutral-point voltage ripple reduction of high frequency injection sensorless control of IPMSM fed by a three-level inverter. The high frequency voltage injection method has been successfully applied to sensorless control for IPMSM at low speed region. In the process of high frequency voltage injection sensorless control for IPMSM, the neutral-point voltage ripple is increased. It should be reduced because it distorts the output current and decreases a life time of DC-link capacitor. The proposed method in this paper reduces the neutral-point voltage ripple by compensating the reference voltage, and the compensation value is calculated simply with reference voltages and currents. The effectiveness of the proposed method is verified by simulation results.

A Study on Using the Interior Finishing Material using Regulation at Multiple-using Businesses (다중이용업소 실내마감재료 사용기준에 관한 연구)

  • Kim, Yong-Sung;Cho, Sung-O
    • Korean Institute of Interior Design Journal
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    • v.22 no.5
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    • pp.216-224
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    • 2013
  • There are the relevant provisions that apply to building regulations about the Building codes, Fire Protection laws, and more Multi-using interior finish materials businesses etc. The differences between these regulations are as follows: The Building codes is defined the main use of the building according to facilities to used to set the scale by the use of the floor space, On the other hand, Fire Protection laws are the basic purpose and the act of using the architectural space(or sales) by separating object by fire. And Multiple-using Businesses Facilities consist of two regulations engaged in the kind of law and the size of the floor area. One building can not be based on operating facilities and together in Multiple use businesses Law. As such, the Buildings are applied to the Building codes, Fire Protection laws, such as Multi-using Businesses Facilities interior construction industry due to the structural differences in the position of the designer feeling a lot of difficulties and confusion. The Multi-use businesses Facilities engage in the kind of law, the size of the floor area and seating capacity. These can not be based on operating facilities, and consists of two regulations together in one building. This study is purposed to help improving the finish of the interior architecture that is related to the Building code regulations, Fire Protection laws, Multi-using Facilities interior finishing material relevant with the provisions from the law through analyze the case of developed countries, and the current Multiple use Businesses Facilities research range from the law of multiple-using facilities, interior finishing, interior architecture for supervision reasonably and compensation for the interior design. So, Result is as follows: First, interior decorations can be separated the fixed material and the moveable things. second, It should be included multi-using Business though small size business space at the basement floor. third, It should be established statute law that design and construction responsibility. forth, re-testing fire resist performance after some period. and finally, it need to mitigate regulation where be installed sprinkler.

Hardware Implementation of Low-power Display Method for OLED Panel using Adaptive Luminance Decreasing (적응적 휘도 감소를 이용한 OLED 패널의 저전력 디스플레이 방법 및 하드웨어 구현)

  • Cho, Ho-Sang;Choi, Dae-Sung;Seo, In-Seok;Kang, Bong-Soon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.7
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    • pp.1702-1708
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    • 2013
  • OLED has good efficiency of power consumption by having no power consumption from black color as different with LCD. when it has white color, all RGB pixel should be glowing with high power consumption and that can make it has short life time. This paper suggest the way of low power consumption for OLED panel using adaptive luminance enhancement with color compensation and implement it as hardware. This way which is based on luminance information of input image makes converted luminance value from each pixel in real time. There is with using the basic idea of chromaticity reduction algorithm, showing new algorithm of color correction. And performance of proposed method was confirmed by comparing the conventional method in experiments about 48.43% current reduction. The proposed method was designed by Verilog HDL and was verified by using OpenCV and Windows Program.

Paid Peering: Pricing and Adoption Incentives

  • Courcoubetis, Costas;Sdrolias, Kostas;Weber, Richard
    • Journal of Communications and Networks
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    • v.18 no.6
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    • pp.975-988
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    • 2016
  • Large access providers (ISPs) are seeking for new types of business agreements and pricing models to manage network costs and monetize better the provision of last-mile services. A typical paradigm of such new pricing norms is the proliferation of paid peering deals between ISPs and content providers (CPs), while on top of this, some ISPs are already experimenting with usage-based tariffs, usually through data-plans, instead of the typical fixed-based charging. In this work we define as common platform, the infrastructure in which a single ISP transacts with several CPs through peering agreements. In this context, we examine whether, and under which market conditions, the profitability of the involved stakeholders improves when the establishment of this platform is accompanied by a monetary compensation from the CPs to the ISP (paid peering), v.s. a scenario where their deal is a typical settlement-free one. In both cases, we assume that the ISP implements a usage-based access pricing scheme, implying that end-users will pay more for higher transaction rates with the CPs. Our framework captures some of the most important details of the current market, such as the various business models adopted by the CPs, the end-users' evaluation towards the ISP's and CPs' level of investments and the traffic rates per transaction for the offered services. By analysing the equilibrium derived by a leader-follower game, it turns out (among other practical takeaways) that whether or not the profitability of a CP improves, it highly depends on whether its business model is to sell content, or if it obtains its revenue from advertisements. Finally, we extract that consumer surplus is considerably higher under paid peering, which in turn implies improved levels of social welfare.

Impact of Climate Change on the Ocean Environment in the Viewpoint of Paleoclimatology (기후변화가 해양에 미친 영향: 고기후학의 관점에서)

  • Yi, Hi-Il;Shin, Im Chul
    • Atmosphere
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    • v.20 no.3
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    • pp.379-386
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    • 2010
  • Impact of global warming on the ocean environment is reviewed based on most recently published publications. The most significant impact of global warming on marine environment is due to the melting of mountain and continental glaciers. Ice melting causes slow down and/or shut down of thermohaline circulation, and makes hypoxic environment for the first time, then makes anoxic with time. This can cause decreasing biodiversity, and finally makes global extinction of animals and plants. Furthermore, global warming causes sea-level rise, soil erosion and changes in calcium carbonate compensation depth (CCD). These changes also can make marine ecosystem unstable. If we emit carbon dioxide at a current rate, the global mean temperature will rise at least $6^{\circ}C$ at the end of this century, as predicted by IPCC (Intergovernmental Panel on Climate Change). In this case, the ocean waters become acidic and anoxic, and the thermohaline circulation will be halted, and marine ecosystems collapsed.

Dual-Level LVDS Circuit with Common Mode Bias Compensation Technique for LCD Driver ICs (공통모드 전압 보정기능을 갖는 LCD 드라이버용 듀얼모드 LVDS 전송회로)

  • Kim Doo-Hwan;Kim Ki-Sun;Cho Kyoung-Rok
    • The Journal of the Korea Contents Association
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    • v.6 no.3
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    • pp.38-45
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    • 2006
  • A dual-level low voltage differential signalling (DLVDS) circuit is proposed aiming at reducing transmission lines for a LCD driver IC. We apply two data to the proposed DLVDS circuit as inputs. Then, the transmitter converts two inputs to two kinds of fully differential signals. In this circuit, two transmission lines are sufficient to transfer two inputs while keeping the LVDS feature. However, the circuit has a common mode bias fluctuation due to difference of the input bias and the reference bias. We compensate the common mode bias fluctuation using a feedback circuit of the current source bias. The receiver recovers the original input data through a level decoding circuit. We fabricated the proposed circuit using $0.25{\mu}m$ CMOS technology. The simulation results of proposed circuit shows 1-Gbps/2-line data rate and 35mW power consumption at 2.5V supply voltage, respectively.

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Problems in the Medical Dispute Medication System and Improvement Plan (의료분쟁조정제도 운영상의 문제점 및 개선방안)

  • Choi, Jang Seop
    • The Korean Society of Law and Medicine
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    • v.15 no.2
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    • pp.91-122
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    • 2014
  • For a variety of reasons, the number of medical disputes is continuously rising. Due to the intrinsic qualities of medical treatments, one would find it more apt to subject medical disputes to general conflict resolution procedures rather than to once-for-all decisions under legal suits. To address the increasing medical disputes with greater professionalism and efficiency, the Medical Disputes Mediation Act was enacted and a medical dispute mediation system put in place, while drawbacks have been blamed to both. The current mediation procedures require the respondent's agreement as a disclosure requirement. A reasonable improvement to this would be to amend the regulation of agreement supposition, or to enforce procedural participation only to public health facilities managed by the national or regional government. Furthermore, small claims cases of 20 million KRW or less in claim may be considered for conciliation-prepositive principle. The concentration on small claim medical disputes is a phenomenon that can be addressed by carrying out maximum authentication commissions or similar measures, one of the solutions by enhancing the public trust in the Korea Medical Dispute Mediation and Arbitration Agency. The proper management of medical authentication teams is one way to address the existing problems in the authentication system. For this, the number of team members shall be increased under more flexible authentication procedures. All indemnity resources for medical accidents of force majeure must be borne by the Government, for it is the body principally responsible for social compensation. Placing this cost on the establisher of the subject medical facility holds the possibility of violating fundamental rights. While the costs for subrogation payment system for damages may be borne by the healthcare facility establisher, a deposit-based system must be created for cases in which the facility shuts down, without holding the responsibility for accident cause. Such change to a deposit-based system will evade the controversies of unconstitutionality, etc.

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