• Title/Summary/Keyword: Charge Control

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Characteristics Investigation of Organic Light Emitting Diodes Using Numerical Device Simulation

  • Lee, Yang-Soo;Park, Jae-Hoon;Choi, Jong-Sun
    • 한국정보디스플레이학회:학술대회논문집
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    • 2003.07a
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    • pp.28-31
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    • 2003
  • We have investigated the electrical characteristics of the organic light emitting diodes (OLEDs) using the numerical device simulation. The current-voltage characteristics, the charge carrier concentrations, and the recombination rate profiles are presented. The simulation results of the effects of the various device parameters on the device characteristics are discussed.

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Hazard analysis for electrostatic of Electrostatic removing wear about combustible gas (가연성가스에 대한 정전기 대전방지복의 정전기 위험성 평가)

  • Chung jae hee;Seo dae won;Koo ja hyeuk;Lee yuung chul;Cho byung hak;Park sung soo;Rew keun chang;Hong Seong-Gyeong;Kim Jun-Ho
    • Journal of the Korean Institute of Gas
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    • v.4 no.2 s.10
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    • pp.33-36
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    • 2000
  • As a result of electrostatic hazard analysis of electrostatic removing wear about combustible gas, in accordance with using period, character of charge voltage is shown that propensity is increased. but character of electrostatic charge amount is below standard(0.6 $\mu$C) of the hazard of electrostatic removing wear, It would seem that character of charge voltage is raised because of swelling phenomenon of the normal fiber and other phenomena. Besides, In some case '96 parka of electrostatic removing wear shown as 0.82$\mu$C that exceed the uppermost limit of the fire and explosion. Therefore, countermeasure or improvement and control are needed.

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A Low Power ROM Using A Single Charge Sharing Capacitor and Hierarchical Bit Line (한 개의 전하공유 커패시터와 계층적 비트라인을 이용한 저전력 롬)

  • Yang, Byung-Do
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.44 no.1
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    • pp.76-83
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    • 2007
  • This paper describes a low power ROM using single charge-sharing capacitor and hierarchical bit line (SCSC-ROM). The SCSC-ROM reduces the power consumption in bit lines. It lowers the swing voltage of bit lines to a very small voltage by using a charge-sharing technique with a single capacitor. It implements the capacitor with dummy bit lines to improve noise immunity and make easy to design. The hierarchical bit line further saves the power by reducing the capacitance in bit lines. The SCSC-ROM also reduces the power consumption in control unit and predecoder by using the hierarchical word line decoder. The simulation result shows that the SCSC-ROM with $4K{\times}32bits$consumes only 37% power of a conventional ROM. A SCSC-ROM chip is fabricated in a $0.25{\mu}m$ CMOS process. It consumes 8.2mW at 240MHz with 2.5V.

Effect of Charge Carrier Lipid on Skin Penetration, Retention, and Hair Growth of Topically Applied Finasteride-Containing Liposomes

  • Lee, Sang-Im;Nagayya-Sriraman, Santhosh-Kumar;Shanmugam, Srinivasan;Baskaran, Rengarajan;Yong, Chul-Soon;Yoon, Sang-Kwon;Choi, Han-Gon;Yoo, Bong-Kyu
    • Biomolecules & Therapeutics
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    • v.19 no.2
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    • pp.231-236
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    • 2011
  • The aim of this study was to investigate the effect of charge carrier lipid on the skin penetration, retention, and hair growth of topically applied finasteride-containing liposomes. Finasteride-containing liposomes were prepared by traditional thin film hydration method using Phospholipon$^{(R)}$ 85 G and cholesterol with or without charge carrier lipid (1,2 dimyristoyl-sn-glycero-3-phosphate or 1,2-dioleoyl-trimethylammonium-propane for anionic and cationic charge, respectively). Freshly prepared finasteride-containing liposome suspension was applied on the hairless mouse skin, and skin penetration and retention were measured using Keshary-Chien diffusion cell. Non-liposomal formulation (ethanol 10% solution containing 0.5 mg/ml of FNS) was also used as a control. The amount of finasteride in the diffusion cell and mouse skin was measured by HPLC. The hair growth was evaluated using depilated male C57BL/6N mice. Mean particle size of all finasteride-containing liposomes was less than a micron, and polydispersity index revealed size homogeneity. Skin penetration and retention studies showed that significantly less amount of finasteride was penetrated when applied as anionic liposome while more amount of the drug was retained. Specifically, in liposome prepared with 10% anionic charge carrier lipid, penetration was 12.99 ${\mu}g/cm^2$ while retention was 79.23 ${\mu}g/cm^2$ after 24 h of application. In hair growth study, finasteride-containing anionic liposomes showed moderate efficacy, but the efficacy was not found when applied as cationic liposomes. In conclusion, topical application of finasteride using anionic liposome formulation appears to be useful option for the treatment of androgenetic alopecia to avoid systemic side effects of the drug.

Design of Charge and Discharge Monitoring System for Secondary Batteries of Hybrid Electric Vehicle (하이브리드 전기자동차용 2차전지 충방전 모니터링 시스템 설계)

  • Lee, Jun-Ha;Lee, Kang-Ho;Choi, Jong-Ho
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.8
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    • pp.157-161
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    • 2010
  • Most of air pollution in a metropolis is the result of exhaust gas emissions from automotive vehicles, and the world-wide regulation against environmental pollution is becoming more strict. Moreover the demand on development and supply of an environment-friendly automobile is increasing and the market share about that is expected to grow rapidly in this time of high oil price. The secondary batteries the most important component to store the electrical energy in hybrid electric vehicle. It needs to the higher power characteristics to emit the energy instantaneous. In this paper, we proposed the system to monitor reliably the charge and discharge states of the secondary batteries for hybrid electric vehicle. The material is about SW and HW module the software and hardware module mounted on the charge and discharge system and the monitoring system to control the charge and discharge performance effectively.

Stable Desalination of Hardness Substances through Charge Control in a Capacitive Deionization System (축전식 탈염 시스템에서 전하량 제어를 통한 경도물질의 안정적인 탈염)

  • Kim, Yoon-Tae;Choi, Jae-Hwan
    • Applied Chemistry for Engineering
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    • v.30 no.4
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    • pp.472-478
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    • 2019
  • A stable desalination method of the hardness substance such as $Ca^{2+}$ by controlling the total charge (TC) supplied to the membrane capacitive deionization (MCDI) cell was studied. The adsorption (1.5 V) and desorption (0.0 V) were repeated 30 times while varying the TC in the adsorption process. The concentration and pH of effluent, adsorption and desorption amounts, current densities and cell potentials were analyzed in the desalination process. The maximum allowable charge (MAC) of the carbon electrode used in MCDI cell was measured to be 46 C/g. As a result of operation at TC (40 C/g) below the MAC value, electrode reactions did not occur, resulted in the stable desalination characteristics for a long-term operation. When operating at TCs (50, 60 C/g) above the MAC value, however, the concentration and pH of effluent varied greatly. Also, the scale was formed on the electrode surface due to electrode reactions, and the electric resistance of the cell gradually increased. It was thus concluded that it is possible to remove stably the hardness substance without any electrode reactions by controlling the charge supplied to MCDI cell during the adsorption process.

A CFD Modeling of Heat Generation and Charge-Discharge Behavior of a Li-ion Secondary Battery (Li-ion 이차전지의 충방전 시 발열 및 충방전 특성의 CFD 모델링)

  • Kang, Hyeji;Park, Hongbeom;Han, Kyoungho;Yoon, Do Young
    • Journal of the Korean Electrochemical Society
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    • v.19 no.3
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    • pp.114-121
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    • 2016
  • This study investigates a CFD modeling of the charge-discharge behavior due to heat generation during charge-discharge cycles of a Li-ion secondary battery(LIB). Present LIB system adopted a current-density equation, heat and mass transfer governing equations upon the 1-dimensional system to the thickness direction for the rectangular pouch configuration. According to the 3-kinds of the charge-discharge current densities of 1C($17.5A/m^2$), 3C($52.5A/m^2$) and 5C($87.5A/m^2$) subject to a 3 V of cut-off voltage, a constant-temperature system at 298 K and three different heat generating systems were analyzed with comparison. Battery capacity decreases with increment of charge-discharge densities not only at the constant-temperature system but also at the heat-generating system. The time for charge-discharge cycles increases at the heat-generating system compare to the constant-temperature system. These trends are considered that the increase of temperature due to heat generation causes the decrement of equilibrium potential of electrodes and the increment of diffusivity of Li ions. Furthermore, cooling effects were discussed in order to control the influence of heat generation due to charge-discharge behavior of a Li-ion secondary battery.

A Study on the Equity of the Charges Established to be Imposed on Damaging Activities of Natural Resources -A Comparative Study of Ecosystem Conservation Cooperation Charge and Replacement Charge for Forest Resources Creation- (자연환경 훼손에 관한 부담금의 형평성 제고방안 -생태계보전협력금과 대체산림자원조성비의 비교를 중심으로-)

  • Bang, Sang-Weon;Yoon, Ick-June
    • Journal of Environmental Policy
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    • v.8 no.2
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    • pp.25-61
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    • 2009
  • These days, environmental policies have changed from being command and control systems toward economic incentive systems, with various incentives having been established by OECD countries. In Korea, many environmental charges have been established in order to diminish activities which damage natural resources. Among them, the Ecosystem Conservation Cooperation Charge and the Replacement Charge for Forest Resources Creation are considered to be representative environmental charges. These charges, along with a few others, were designed to encourage efforts to protect natural resources. The charges include a number of different features, utilize varying methods, and altered ranges of jurisdiction. However, the charges may pose serious inequity problems in terms of their estimated values and their conditions of reduction and exemption. For instance, although the Ecosystem Conservation Cooperation Charge is a primary charge applied to natural resource damage, the charge does not fully secure its original objectives due to its low levy and limited range of provisions. Moreover, the Replacement Charge for Forest Resources Creation has been criticized because of similar reduction and exemption provisions. Therefore, this study analyzes the inequity problems associated with the charges and proposes solutions. First of all, the Ecosystem Conservation Cooperation Charge should be redesigned in such a way that it reflects the substantial value of natural resource damage through either abrogate or increased maximum limits of the charge. With regard to the Replacement Charge for Forest Resources Creation, the cases and ranges of reduction and exemption provisions should be narrowed. Finally, the charges collected should be expended in conformity with their original objectives, and their expenditure should be restricted to either restoration activities or activities directly related to compensation and mitigation of damaged natural resources.

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Implementation of One-Cycle Control for Switched Capacitor Converters

  • Yang, Lei;Zhang, Xiaobin;Li, Guann-pyng
    • Journal of Power Electronics
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    • v.16 no.6
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    • pp.2057-2066
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    • 2016
  • An extension of the one-cycle control (OCC) method for switched-capacitor (SC) converters is proposed in this paper, featuring a fast dynamic response, wide line and load operation ranges, and simplicity in implementation. To illustrate the operation principle of this nonlinear control method and to demonstrate its simplicity in design, a dual-phase unity gain SC converter is examined. A new control loop based on the charge balance in a flying capacitor is formulated for the OCC technique and implemented with a 15W dual-phase unity gain SC converter on a circuit board for control verification. The obtained experimental results show that external disturbances can be rejected in one switching cycle by the OCC controlled SC converter with good line and load regulations. When compared to other control methods, the proposed nonlinear control loop exhibits superior dynamic performance in suppressing input and load disturbances.

Development of Orofacial Pains Therapy System based on Acupuncture Principles (침치료 원리를 이용한 안면 통증 치료기 개발)

  • Lee Yong-Heum;Bak Chang-Gye
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.5
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    • pp.1045-1051
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    • 2005
  • We developed an orofacial pains diagnosis/therapy system which can enlarge a therapy effect through a new stimulation. Contrary to its established method, this therapy system(DDTS-1) is a treating method which absorbs a surplus ion charge- the cause of an outbreak of a pain-of the human body using a capacitor. Absorbing a surplus ion charge of the human body with effect, it obtained optimal parameters which is control signal to control charging/discharging a capacitor to be 6Hz, and capacitance to be $0.1\~0.33{\mu}F.$ Through clinical demonstration, experimented on among patients-namely dental pain patients, joint disorders patients, and trigeminal neuralgia patients to verification of system. In result, an EAST stimulater had a very low change of abnormal potential against normal potential before/after being placed under medical care. DDTS-1 showed obvious differences that two potentials are one and the same potential or one potential is similar to the other one. DDTS-1 comparing with EAST showed the remedial value of the comparative advantage in all the medical treatment of pains. Therefore, stimulation of DDTS-1 is more effective than the existing electric stimulation. We verified its validity of ion charge absorption in the human body using capacitor which presented the present thesis. That is, we verified theoretical adequacy of control action in a pain, and its efficiency as well as confidence.