• Title/Summary/Keyword: Free-Of-Charge supply

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A Study on Improvement Plans of School Facilities Free-Of-Charge Supply System (학교시설 무상공급 재정성과 및 제도개선 방안 연구)

  • Lee, Sang-Min
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.14 no.3
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    • pp.18-27
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    • 2015
  • 2009 As the School District is amended as a metropolitan area public development operators obliged to free supply of school facilities contribute to the streamlining of the provincial education funding, and although institutions shortly became implemented in earnest, the effect has been, despite a number of problems occur. In this study, analysis of these school facilities free of charge supply system on the status and problems through surveys, and suggests directions for future drafting and improving legislation.

Overstress-Free 4 × VDD Switch in a Generic Logic Process Supporting High and Low Voltage Modes

  • Song, Seung-Hwan;Kim, Jongyeon;Kim, Chris H.
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.15 no.6
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    • pp.664-670
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    • 2015
  • A four-times-VDD switch that supports high and low voltage mode operations is demonstrated in a generic 65 nm logic process. The proposed switch shows the robust operation for supply voltages ranging from VDD to $4{\times}VDD$. A cascaded voltage switch and a voltage doubler based charge pump generate the intermediate supply voltage levels required for the proposed high voltage switch. All the high voltage circuits developed in this work can be implemented using standard logic transistors without being subject to any voltage overstress.

Design of CMOS Fractional-N Frequency Synthesizer for Bluetooth system (Bluetooth용 CMOS Fractional-N 주파수 합성기의 설계)

  • Lee, Sang-Jin;Lee, Ju-Sang;Yu, Sang-Dae
    • Proceedings of the KIEE Conference
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    • 2003.11c
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    • pp.890-893
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    • 2003
  • In this paper, we have designed the fractional-N frequency synthesizer for bluetooth system using 0.35-um CMOS technology and 3.3-V single power supply. The designed synthesizer consist of phase-frequency detector (PFD), charge pump, loop filter, voltage controlled oscillator (VCO), frequency divider, and sigma-delta modulator. A dead zone free PFD is used and a modified charge pump having active cascode transistors is used. A Multi-modulus prescaler having CML D flip-flop is used and VCO having a tuning range from 746 MHz to 2.632 GHz at 3.3 V power supply is used. Total power dissipation is 32 mW and phase noise is -118 dBc/Hz at 1 MHz offset.

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A Study on the Spray and Combustion Characteristics of Direct-injection LPG (직접분사식 LPG의 분무 및 연소 특성에 관한 연구)

  • Hwang, Seong-Ill;Chung, Sung-Sik;Yeom, Jeong-Kuk
    • Journal of Power System Engineering
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    • v.19 no.2
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    • pp.40-48
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    • 2015
  • As advantages of LPG-DI engine, LPG is directly injected into combustion chamber during compression stroke to reduce compression temperature, prevent knock and spontaneous combustion, and adjust engine output using the amount of directly injected fuel, thereby reducing pumping loss caused by throttle valve. Stratified charge can be supplied nearby spark plugs to allow for overall lean combustion, which improves thermal efficiency and can cope with problems regarding emission regulations. In addition, it is characterized by free designing of intake manifold. Despite the fact that LPG-DI has many advantages as described above, there is lack of detailed investigation and study on spray characteristics, combustion flame characteristics, and ignition probability. In this study, a visualization experiment system that consists of visualization combustion chamber, air supply control system, emission control system, LPG fuel supply system, electronic control system and image data acquisition system was designed and manufactured. For supply of stratified charge in the combustion chamber, alignment of injector and spark plugs was made linear.

Electric Power Demand Prospect Pattern System (전력 수요 예측 패턴 시스템 설계)

  • Yu, seung-hyun;Lee, joung-myung;Park, han-ho;Kwak, nae-joung;Lee, hyun-tae;Jeon, jae-sung
    • Proceedings of the Korea Contents Association Conference
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    • 2008.05a
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    • pp.112-115
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    • 2008
  • Recently, In Korea Electric power Corporation guarantee free using, which separate a class of electric supply with a group of generates electricity and supply, so a market price is decided by demand and supply that take part in a tender. In this treatise predict about demand of power by abstracting a pattern cause it (temperature and economic growth). Also it proposes market price of the best electricity power generation with predicted data that is made database and is showed by Web. The proposed system is increased satisfaction of consumer through smoothness of power supply and demand that rises competitiveness through exactly estimated demand at power supply and demand and supply market will open the future. Moreover consumers can reduce expenses of basic charge. Because they beforehand predict and analyze a mount of power spending with former times so a provider concludes the lowest price and reduction effect of basic charge that needed producing of power.

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A Test Input Sequence for Test Time Reduction of $I_{DDQ}$ Testing

  • Ohnishi, Takahiro;Yotsuyanagi, Hiroyuki;Hashizume, Masaki;Tamesada, Takeomi
    • Proceedings of the IEEK Conference
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    • 2000.07a
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    • pp.367-370
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    • 2000
  • It is shown that $I_{DDQ}$ testing is very useful for shipping fault-free CMOS ICs. However, test time of $I_{DDQ}$ testing is extremely larger than one of logic testing. In this paper, a new test input sequence generation methodology is proposed to reduce the test time of $I_{DDQ}$ testing. At first, it is Shown that $I_{DDQ}$ test time Will be denominated by charge supply current for load capacitance of gates whose output logic values are changed by test input vector application and the charge current depends on input sequence of test vectors. After that, a test input sequence generation methodology is proposed. The feasibility is checked by some experiments.riments.

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Polymer Electrolyte Membranes Consisting of PVA-g-POEM Graft Copolymers for Supercapacitors (슈퍼커패시터용 PVA-g-POEM 가지형 공중합체로 구성된 고분자 전해질막)

  • Park, Min Su;Kim, Do Hyun;Lee, Jae Hun;Kim, Jong Hak
    • Membrane Journal
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    • v.29 no.6
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    • pp.323-328
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    • 2019
  • It is a highly important problem for mankind to supply sufficient energy, which has been connected to production and supply of electricity. In terms of the problems, this study fabricated a new sort of solid polymer electrolyte membrane for supercapacitors. The fabricated electrolyte employed grafting poly(oxyethylene methacrylate) (POEM) side chain on poly(vinyl alcohol) (PVA) main chain by free-radical polymerization. It is the first time to utilize PVA-g-POEM graft copolymer as an electrolyte membrane for supercapacitor. The chain behavior of PVA was transformed by grafting POEM side chains, which was analyzed by FT-IR spectra. Also, the capacitance performances of fabricated supercapacitors were explored by cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and ragone plot. We suggest a new point, the grafting of the electrolyte of supercapacitor in this study.

Equilibrium Thermodynamics of Chemical Reaction Coupled with Other Interfacial Reactions Such as Charge Transfer by Electron, Colligative Dissolution and Fine Dispersion: A Focus on Distinction between Chemical and Electrochemical Equilibria

  • Pyun, Su-Il;Lee, Sung-Jai;Kim, Ju-Sik
    • Journal of the Korean Electrochemical Society
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    • v.11 no.4
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    • pp.227-241
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    • 2008
  • This article involves a unified treatment of equilibrium thermodynamics of the chemical reaction coupled with other interfacial (phase boundary) reactions. The modified (restrictive) chemical potential ${\mu}_k^+$, such as electrochemical potential, hydrostatic-chemical (mechanochemical) potential (exceptionally in the presence of the pressure difference) and surface-chemical potential, was first introduced under the isothermal and isobaric conditions. This article then enlightened the equilibrium conditions in case where the release of chemical energy is counterbalanced by the supply of electrical energy, by the supply of hydrostatic work (exceptionally in the presence of ${\Delta}p$), and finally by the release of surface energy, respectively, at constant temperature T and pressure p in terms of the modified chemical potential ${\mu}_k^+$. Finally, this paper focussed on the difference between chemical and electrochemical equilibria based upon the fundamentals of the isothermal and isobaric equilibrium conditions described above.

A Feasibility Study of the Construction Project in Pre-Design Phase (건설 프로젝트의 사업타당성 분석에 관한 연구)

  • 노병옥;이상범;임남기
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2002.05a
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    • pp.109-113
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    • 2002
  • Urban public service is goods and activities which satisfy public demands for the political, social, economic, cultural activity and household affairs of individual or groups and which urban government supply with free of charge. In view of government, in addition to fairness of facilities location, location of such facilities are to be determined the respect to cost of locating facilities and developmental direction in the future. Therefore, it is necessary to study on feasibility. A feasibility study Is an effective tool in determining the decision of investment or not and the level of investment priority on Projects requiring a sizeable investment and the feasibility of a project. The first, it is to select reasonable location. It was selected four and two by consideration of facilities distribution and connection with others. Six proposal selected was estimated by five element of approach, demand, symbol, reality, environment. In result proposal I was chosen. The next, it is to estimate scales. The finally, it is to study on economical efficiency. Net Present Value was came out ₩4.4billion by 20years and Inter Rate of Return showed up 11%. in addition, it offer various benefit by public facilities. In conclusion, this project is reasonable.

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Optimized Charging in Large-Scale Deployed WSNs with Mobile Charger

  • Qin, Zhenquan;Lu, Bingxian;Zhu, Ming;Sun, Liang;Shu, Lei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.12
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    • pp.5307-5327
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    • 2016
  • Restricted by finite battery energy, traditional wireless sensor networks (WSNs) can only maintain for a limited period of time, resulting in serious performance bottleneck in long-term deployment of WSN. Fortunately, the advancement in the wireless energy transfer technology provides a potential to free WSNs from limited energy supply and remain perpetual operational. A mobile charger called wireless charging vehicle (WCV) is employed to periodically charge each sensor node and keep its energy level above the minimum threshold. Aiming at maximizing the ratio of the WCV's vocation time over the cycle time as well as guaranteeing the perpetual operation of networks, we propose a feasible and optimal solution to this issue within the context of a real-time large-scale deployed WSN. First, we develop two different types of charging cycles: initialization cycles and renewable cycles and give relevant algorithms to construct these two cycles for each sensor node. We then formulate the optimization problem into an optimal construction algorithm and prove its correctness through theoretical analysis. Finally, we conduct extensive simulations to demonstrate the effectiveness of our proposed algorithms.