• 제목/요약/키워드: P-V curve

검색결과 297건 처리시간 0.024초

임파종환자에서 반코마이신의 임상약물동태 (Clinical Pharmacokinetics of Vancomycin in Lymphoma Patients and Normal Volunteers)

  • 김재호;최준식;이진환
    • 한국임상약학회지
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    • 제9권2호
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    • pp.88-91
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    • 1999
  • The purpose of this study was to compare the pkarmacokinetic parameters of vancomycin using a 2-compartment model in 8 Korean healthy volunteers and 8 lymphoma patients. Vancomycin (1.0 g) was administered by IV infusion over 60 minutes. The $\beta-phase$ rate constant $(\beta)$, apparent volume of distribution at steady srate $(V_{ss})$, total body clearance (CL) and area under the plasma level-time curve (AUC) of vancomycin in healthy volunteers were $0.15\pm0.02\;hr^{-1},\;33.8\pm4.12\;L/kg,\;5.36\pm0.61\;L/hr\;and\;185.8\pm20.5\;{\mu}g/ml{\cdot}hr$, respectively. The corresponding values in lymphoma patients ere $0.09\pm0.02\;hr^{-1},\;38.2\pm5.11\;L/kg,\;4.58\pm0.52\;L/hr\;and\;218.3\pm22.9\;{\mu}g/ml{\cdot}hr$. There were significant differences (p<0.05) in ${\beta}$ and CL between healthy volunteers and lymphoma patients.

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상악구치 교합면의 design 조각법에 관한 연구 (A Study on the design waxup technique for maxillary molar occlusion)

  • 문희경
    • 대한치과기공학회지
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    • 제21권1호
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    • pp.97-114
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    • 1999
  • The first function of occlusion is mastication. Therefore the functional restoration of occlusal surface is very important. The restoration of occlusal surface is three method as wax bite technique, F.G.P. technique, cone technique. Many dental technician is using compound method. I have knew common point on each teeth during I have waxing up wax pattern. So I studied on the design waxup technique for maxillary molar occlusion. The results of the study were as follows ; 1. The dam wax up method can restore axial contour of teeth very easy and make short working time of wax pattern. 2. The height of dam must be same with cusp of adjacent teeth. 3. Automatically the contour of tooth is appeared if the contour of dam is relationship with cuspid line of adjacent teeth. 4. The height of contour of buccal, lingual surface is formed natural curve to add fluid wax by gravitation. 5. The development groove of Maxillary premolar is appeared V form. 6. The development groove of Maxillary molar is appeared W form. 7. The embrasure is formed to carve around contact point area as round convex. It affects to axial form of tooth. 8. I was knew that the lingual groove and stuart's groove of molar runs parallel with oblique ridge. 9. The buccal groove of molar is formed parallel with direction of teeth arrangement.

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Power Gain during Partial Shade Condition with Partial Shade Loss Compensation in Photovoltaic System

  • Yoon, Byung-Keun;Yun, Chul;Cho, Nae-Soo;Choi, Sang-Back;Jin, Yong-Su;Kwon, Woo-Hyen
    • Journal of Electrical Engineering and Technology
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    • 제13권2호
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    • pp.769-780
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    • 2018
  • This paper presents an analysis of the power gain under partial shading conditions (PSC) when the partial shade loss is being compensated in photovoltaic(PV) system. To analyze the power gain, our study divides the mismatch loss into partial shade loss and operating point loss. Partial shade loss is defined as the power difference between a normal string and a partially shaded string at the maximum power point (MPP). Operating point loss is defined as the power loss due to the operating point shift while following the MPP of the PV array. Partial shading in a PV system affects the maximum power point tracking (MPPT) control by creating multiple MPPs, which causes mismatch losses. Several MPPT algorithms have been suggested to solve the multiple MPP problems. Among these, mismatch compensation algorithms require additional power to compensate for the mismatch loss; however, these algorithms do not consider the gain or loss between the input power required for compensation and the increased output power obtained after compensation. This paper analyzes the power gain resulting from the partial shade loss compensation under PSC, using the V-P curve of the PV system, and verifies that power gain existence by simulation and experiment.

Nanogold-modified Carbon Paste Electrode for the Determination of Atenolol in Pharmaceutical Formulations and Urine by Voltammetric Methods

  • Behpour, M.;Honarmand, E.;Ghoreishi, S.M.
    • Bulletin of the Korean Chemical Society
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    • 제31권4호
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    • pp.845-849
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    • 2010
  • A gold nanoparticles modified carbon paste electrode (GN-CPE) has been used for the determination of atenolol (ATN) in drug formulations by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronocoulometric methods. The results revealed that the modified electrode shows an electrocatalytic activity toward the anodic oxidation of atenolol by a marked enhancement in the current response in buffered solution at pH 10.0. The anodic peak potential shifts by -80.0 mV when compared with the potential using bare carbon paste electrde. A linear analytical curve was observed in the range of $1.96\;{\times}\;10^{-6}$ to $9.09\;{\times}\;10^{-4}\;mol\;L^{-1}$. The detection limit for this method is $7.3\;{\times}\;10^{-8}\;mol\;L^{-1}$. The method was then successfully applied to the determination of atenolol in tablets and human urine. The percent recoveries in urine ranged from 92.0 to 110.0%.

Ion Exchange Recovery of Rhenium and Its Determination in Aqueous Solutions by Diffuse Reflection Spectroscopy

  • Kalyakina, O.P.;Kononova, O.N.;Kachin, S.V.;Kholmogorov, A.G.
    • Bulletin of the Korean Chemical Society
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    • 제25권1호
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    • pp.79-84
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    • 2004
  • The existing technological schemes for processing rhenium-containing raw materials involve the recovery of Re from solutions, which can be effectively achieved by anion exchange method. The application of anion exchange also allows to study rhenium state in aqueous solutions and to develop analytical control methods. The present work is focused on investigation of ion exchange equilibrium in the analytical system Re(VII)-HCl-$SnCl_2$-KSCN-anion exchanger by means of sorption-desorption method as well as by electron, IR- and diffuse reflection spectroscopy. It was shown that rhenium can be quantitatively recovered from this system. It is proposed to use the sorption-spectroscopic method for Re(VII) determination in aqueous solutions. The calibration curve is linear in the concentration range of 0.5-20.0 mg/L (sample volume is 25.0 mL) and the detection limit is 0.05 mg/L. The presence of Mo(VI), Cu(II), Fe(II, III), Ni(II), Zn(II) as well as $K^+,\;Na^+$ do not hinder the solid-phase determination of rhenium. Rhenium (VII) determination by diffuse reflection spectroscopy was carried out in model solutions as well as in samples of river-derived water and in solutions obtained after the dissolution of spent catalysts.

계통안정화를 위한 SMES의 모델링과 적정위치 선정 (A Modeling and Optimal Site of SMES for Power System Stabilization)

  • 김정훈;임재윤;이종필
    • 대한전기학회논문지:전력기술부문A
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    • 제48권5호
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    • pp.494-501
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    • 1999
  • In this research, ANN modeling method of SMES unit is developed for stability analysis, and the optimal site is selected to maximize stabilization effect of SMES unit. The ANN is trained by learning data which is obtained through the application of complex test function into the traditional mathematical mode. In order to verify the validity of proposed modeling method, fault data of sample power system is applied to both the traditional and the ANN models. When the response of traditional and proposed models are compared, the average error for the active and reactive power are 2.51[%], and 0.24[%], respectively. From the comparison, the relevance of proposed method is validated. For the transient stability analysis, an application method of the proposed model is presented, and the transient stability performance index, which describes system stabilization effect of SMES at disturbance, is also suggested, and optimal site selection method of SMES is presented. In the viewpoint of the voltage stability, system stabilization criterion of local bus is presented from P­V curve, and then optimal site which can maximize the voltage stabilization of the whole power system, is decided from the proposed voltage stability performance index.

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Real-Time Maximum Power Point Tracking Method Based on Three Points Approximation by Digital Controller for PV System

  • Kim, Seung-Tak;Bang, Tae-Ho;Lee, Seong-Chan;Park, Jung-Wook
    • Journal of Electrical Engineering and Technology
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    • 제9권5호
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    • pp.1447-1453
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    • 2014
  • This paper proposes the new method based on the availability of three points measurement and convexity of photovoltaic (PV) curve characteristic at the maximum power point (MPP). In general, the MPP tracking (MPPT) function is the important part of all PV systems due to their power-voltage (P-V) characteristics related with weather conditions. Then, the analog-to-digital converter (ADC) and low pass filter (LPF) are required to measure the voltage and current for MPPT by the digital controller, which is used to implement the PV power conditioning system (PCS). The measurement and quantization error due to rounding or truncation in ADC and the delay of LPF might degrade the reliability of MPPT. To overcome this limitation, the proposed method is proposed while improving the performances in both steady-state and dynamic responses based on the detailed investigation of its properties for availability and convexity. The performances of proposed method are evaluated with the several case studies by the PSCAD/EMTDC$^{(R)}$ simulation. Then, the experimental results are given to verify its feasibility in real-time.

정전분무법을 이용한 염료감응형 태양전지의 $TiO_2$ 박막 특성에 관한 연구 (A Study on the Characteristics of $TiO_2$ thin Film in Dye-sensitized Solar Cells using Electrospray Method)

  • 김희제;이정기;홍지태;김호성;이동길;허국성;안태풍;장진주
    • 전기학회논문지
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    • 제58권11호
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    • pp.2223-2228
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    • 2009
  • Dye sensitized solar cells(DSCs) have been very economical and easy method to convert solar energy to electricity. DSC can reach low costs in future outdoor power applications. However, to commercialize the DSC, there are still many shortages to overcome such a low efficiency in a large size DSC. In this study, DSCs were fabricated by an electrospray coating method for the $TiO_2$ thin film. They were compared with DSCs prepared by conventional coating methods. We conducted an experiment to obtain the optimized parameters of voltage, flow rate, incident angle and distance in the electrospray method. After we fabricated $TiO_2$ film using that way, we investigated the characteristics of DSC through I-V Curve, SEM and EIS. This novel method shows stable performance with an energy conversion efficiency of 3.44 % under 1 sun illumination (AM 1, $P_{in}$ of $100\;mW/cm^2$).

ARIMA Based Wind Speed Modeling for Wind Farm Reliability Analysis and Cost Estimation

  • Rajeevan, A.K.;Shouri, P.V;Nair, Usha
    • Journal of Electrical Engineering and Technology
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    • 제11권4호
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    • pp.869-877
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    • 2016
  • Necessity has compelled man to improve upon the art of tapping wind energy for power generation; an apt reliever of strain exerted on the non-renewable fossil fuel. The power generation in a Wind Farm (WF) depends on site and wind velocity which varies with time and season which in turn determine wind power modeling. It implies, the development of an accurate wind speed model to predict wind power fluctuations at a particular site is significant. In this paper, Box-Jenkins ARIMA (Auto Regressive Integrated Moving Average) time series model for wind speed is developed for a 99MW wind farm in the southern region of India. Because of the uncertainty in wind power developed, the economic viability and reliability of power generation is significant. Life Cycle Costing (LCC) method is used to determine the economic viability of WF generated power. Reliability models of WF are developed with the help of load curve of the utility grid and Capacity Outage Probability Table (COPT). ARIMA wind speed model is used for developing COPT. The values of annual reliability indices and variations of risk index of the WF with system peak load are calculated. Such reliability models of large WF can be used in generation system planning.

Unusual Electrical Transport Characteristic of the SrSnO3/Nb-Doped SrTiO3 Heterostructure

  • De-Peng Wang;Rui-Feng Niu;Li-Qi Cui;Wei-Tian Wang
    • 한국재료학회지
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    • 제33권6호
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    • pp.229-235
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    • 2023
  • An all-perovskite oxide heterostructure composed of SrSnO3/Nb-doped SrTiO3 was fabricated using the pulsed laser deposition method. In-plane and out-of-plane structural characterization of the fabricated films were analyzed by x-ray diffraction with θ-2θ scans and φ scans. X-ray photoelectron spectroscopy measurement was performed to check the film's composition. The electrical transport characteristic of the heterostructure was determined by applying a pulsed dc bias across the interface. Unusual transport properties of the interface between the SrSnO3 and Nb-doped SrTiO3 were investigated at temperatures from 100 to 300 K. A diodelike rectifying behavior was observed in the temperature-dependent current-voltage (IV) measurements. The forward current showed the typical IV characteristics of p-n junctions or Schottky diodes, and were perfectly fitted using the thermionic emission model. Two regions with different transport mechanism were detected, and the boundary curve was expressed by ln I = -1.28V - 13. Under reverse bias, however, the temperature- dependent IV curves revealed an unusual increase in the reverse-bias current with decreasing temperature, indicating tunneling effects at the interface. The Poole-Frenkel emission was used to explain this electrical transport mechanism under the reverse voltages.