• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.181-184
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• 1999

This paper presents the accurate deembeding method for pad and parasitics of MOSFET device. rad effects are deembedded using THRU LINE, which is much simpler method without laborious fitting procedure compared with conventional OPEN and SHORT pad modeling. Parasitic resistance extraction uses the algebraic relation between increments of inversion layer charge and oxide capacitance. It is especially adequate for insulating gate junction device. Extracted parasitics are verified through comparing modeled and measured S parameters.

• Proceedings of the Optical Society of Korea Conference
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• 2000.02a
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• pp.60-61
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• 2000

홀로그래픽 데이터 저장 장치(holographic data storage)는 1960년대에 이미 아이디어가 출현하였고, 1990년대에 들어서 SLM(spatial light modulator)과 CCD(charge coupled device) 등 관련 기술의 발달과 함께 향후 늘어날 대용량 저장 장치 시장에 대한 전망 등에 힘입어 주목받기 시작하였다. 홀로그래픽 데이터 저장 장치의 중요한 장점은 대용량의 정보를 고속으로 처리할 수 있고, 특히 페이지 단위로는 병렬 접근이 가능하다는 것인데, 이를 위해서 반드시 해결되어야 할 것이 픽셀 매치(pixel-match)이다. (중략)

• Korean Journal of Materials Research
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• v.12 no.11
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• pp.860-864
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• 2002

$Li^{+}$ extraction reactions with ion-exchange type lithium manganese oxide in an aqueous phase were examined using chemical and x-ray diffraction (XRD) analysis. In the process of extraction reaction, the lithium manganese oxide showed a topotactic extraction of $Li^{+ }$ in the aqueous phase mainly through an ion-exchange mechanism, and the $Li^{+}$ extracted samples indicated a high selectivity and a large capacity for $Li^{+}$ . The electronic structures and chemical bonding properties were also studied using a discrete variational (DV)-X$\alpha$ molecular orbital method with cluster model of (Li$Mn_{12}$ $O_{40}$ )$^{27-}$ for tetrahedral sites and ($Li_{7}$ Mn $O_{38}$ )$^{3}$ for octahedral site in $Li_{1.33}$ $Mn_{1.67}$ / $O_{4}$ respectively. Li in the manganese oxides is highly ionized in both sites, but the net charge of Li was greater for tetrahedral sites than octahedral. These calculations suggest that the tetrahedral sites have higher $Li^{+}$ $H^{+}$ exchangeability than the octahedral sites, and are preferable for the selective adsorption for L $i^{+}$ ions.s.

• JSTS:Journal of Semiconductor Technology and Science
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• v.8 no.2
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• pp.115-120
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• 2008

Carrier velocity in the MOSFET channel is the main driving force for improved transistor performance with scaling. We report measurements of the drift velocity of electrons and holes in silicon inversion layers. A technique for extracting effective carrier velocity which is a more accurate extraction method based on the actual inversion charge measurement is used. This method gives more accurate result over the whole range of $V_{ds}$, because it does not assume a linear approximation to obtain the inversion charge and it does not limit the range of applicable $V_{ds}$. For a very short channel length device, the electron velocity overshoot is observed at room temperature in 37 nm MOSFETs while no hole velocity overshoot is observed down to 36 nm. The electron velocity of short channel device was found to be strongly dependent on the longitudinal field.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.3
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• pp.529-536
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• 2019

In order to apply a piezoelectric energy harvester to a smart sensor system, an energy harvest interface circuit including an AC-DC rectifier is required. In this paper, we compared the performance of full bridge rectifier, which is a typical energy harvester interface circuit, and synchronous piezoelectric energy harvest interface circuit by using board-level simulation. As a result, the output power of a synchronous electric charge extraction(: SECE) circuit is about four times larger than that of the full bridge rectifier, and there is little load variation. And a high voltage comparator, which is essential for the SECE circuit for the piezoelectric energy harvester with an output voltage of 40V or more, was designed using 0.35 um BCD process. The SECE circuit using the designed high-voltage comparator proved that the output power is 427 % higher than the FBR circuit.

• Journal of the Korean Chemical Society
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• v.26 no.5
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• pp.326-332
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• 1982

The structure of the complex extracted from an aqueous solution containing methylene blue and tetrafluoroborate with 1,2-dichloroethane has been investigated by comparing IR spectrum of the extract with those of pure components and appeared to be an 1 : 1 contact ion-pair between monovalent ions of opposite charge. The extraction constant obtained from the absorbance data measured at 658nm in 1,2-dichlorethane has a value of 1.1${\times}$at$10^4M{-1}$ 25$^{\circ}$C in the range from 1.43${\times}10^{-2}$ to 2.86${\times}10^{-1}$M HF. In the solvent extraction with nitrobenzene, the identical experiments show that extraction constants are increased with HF concentration possibly due to dissociation of the ion-pair in nitrobenzene.

• Resources Recycling
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• v.13 no.2
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• pp.24-32
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• 2004

Solvent extraction equilibria of Gd with PC88A from chloride solutions were analyzed by considering chemical equilibria. phase equilibria, mass and charge balance equations. The following solvent extraction reaction and equilibrium constant were evaluated from the experimental data performed in this study. $Gd^{3+}$ $+2H_2$$A_2$,$or=GdA_3$HA.or+3 $H^{+}$ , K=3.3 A procedure was suggested to calculate the initial concentration of chloride ion from initial pH and initial concentration of Gd. By applying ionic equilibria, the distribution of Gd complexes with Gd and HCl concentration was obtained. The predicted distribution coefficients of Gd agreed well with the experimental results.

• Advances in nano research
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• v.2 no.1
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• pp.23-56
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• 2014

The significant growth of the Si photovoltaic industry has been so far limited due to the high cost of the Si photovoltaic system. In this regard, the most expensive factors are the intrinsic cost of silicon material and the Si solar cell fabrication processes. Conventional Si solar cells have p-n junctions inside for an efficient extraction of light-generated charge carriers. However, the p-n junction is normally formed through very expensive processes requiring very high temperature (${\sim}1000^{\circ}C$). Therefore, several systems are currently under study to form heterojunctions at low temperatures. Among them, carbon nanotube (CNT)/Si hybrid solar cells are very promising, with power conversion efficiency up to 15%. In these cells, the p-type Si layer is replaced by a semitransparent CNT film deposited at room temperature on the n-doped Si wafer, thus giving rise to an overall reduction of the total Si thickness and to the fabrication of a device with cheaper methods at low temperatures. In particular, the CNT film coating the Si wafer acts as a conductive electrode for charge carrier collection and establishes a built-in voltage for separating photocarriers. Moreover, due to the CNT film optical semitransparency, most of the incoming light is absorbed in Si; thus the efficiency of the CNT/Si device is in principle comparable to that of a conventional Si one. In this paper an overview of several factors at the basis of this device operation and of the suggested improvements to its architecture is given. In addition, still open physical/technological issues are also addressed.

• Journal of Electrical Engineering and Technology
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• v.13 no.5
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• pp.1927-1934
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• 2018

In this paper, we studied the state of charge (SOC) estimation algorithm of a high-capacity lithium secondary battery for electric vehicles (EVs) considering temperature characteristics. Nonlinear characteristics of high-capacity lithium secondary batteries are represented by differential equations in the mathematical form and expressed by the state space equation through battery modeling to extract the characteristic parameters of the lithium secondary battery. Charging and discharging equipment were used to perform characteristic tests for the extraction of parameters of lithium secondary batteries at various temperatures. An extended Kalman filter (EKF) algorithm, a state observer, was used to estimate the state of the battery. The battery capacity and internal resistance of the high-capacity lithium secondary battery were investigated through battery modeling. The proposed modeling was applied to the battery pack for EVs to estimate the state of the battery. We confirmed the feasibility of the proposed study by comparing the estimated SOC values and the SOC values from the experiment. The proposed method using the EKF is expected to be highly applicable in estimating the state of the high-capacity rechargeable lithium battery pack for electric vehicles.

• Women's Health Nursing
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• v.25 no.1
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• pp.99-111
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• 2019

Purpose: To develop nurses' educational needs scale for woman with infertility. Methods: A total of 201 nurses in charge of infertility health services in 4 infertility hospitals and 1 public health center were enrolled for this study. The scale was developed through literature review, in-depth interview, development of preliminary items, verification of content validity, development of secondary items, verification of construct validity, and extraction of final items. Data were analyzed using item analysis, exploratory factor analysis, Pearson's correlation coefficients, and Cronbach's ${\alpha}$. Results: Nurses' educational needs scale for women with infertility consisted of 41 items. Three factors (education for disease and symptom of infertility, supporting and counselling for infertility patients, and education for daily life of infertile patients) explained 63.7% of the total variance. Conclusions: Nurses' educational needs scale for woman with infertility demonstrated acceptable validity and reliability. Its items could be used to assess the level of educational needs for nurses in charge of infertility health services.