• Title/Summary/Keyword: Quantum-mechanical

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C-V Characteristics in Nanometer Scale MuGFETs with Considering Quantum Effects (양자 현상을 고려한 나노미터 스케일 MUGFETS의 C-V 특성)

  • Yun, Se-Re-Na;Yu, Chong-Gun;Park, Jong-Tae
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.45 no.11
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    • pp.1-7
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    • 2008
  • In this work, a two dimensional, self-consistent Poisson-$Schr{\ddot{o}}dinger$ solver has been implemented to study C-V characteristics in nanometer scale MuGFETs with considering quantum effects. The quantum-mechanical effects on gate-channel capacitance for different device dimension and gate configurations of nanometer scale MuGFETs have been analyzed. It has been found that 4he gate-channel capacitance per unit gate area is increased as the device dimension decreases. For different gate configurations, the gate-channel capacitance is decreased with increase of effective gate number. Those resu1ts have been explained by the distribution profile of electron concentration in the silicon surface and inversion capacitance. The length of inversion-layer centroid has been calculated from inversion capacitance with device dimension and gate configurations.

Development of 2W-Level Wireless Powered Energy Harvesting Receiver using 60Hz power line in Electricity Cable Tunnel (전력구 내 지중선을 이용한 2W급 상용주파수 무선전력 수신장치 개발)

  • Jang, Gi-Chan;Choi, Bo-Hwan;Rim, Chun-Taek
    • The Transactions of the Korean Institute of Power Electronics
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    • v.21 no.4
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    • pp.296-301
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    • 2016
  • Using high magnetic flux from a 60 Hz high-current cable, a 2 W wireless-powered energy harvesting receiver for sensor operation, internet of things (IoT) devices, and LED lights inside electrical cable tunnels is proposed. The proposed receiver comprises a copper coil with a high number of turns, a ring-shaped ferromagnetic core, a capacitor for compensating for the impedance of the coil in series, and a rectifier with various types of loads, such as sensors, IoT devices, and LEDs. To achieve safe and easy installation around the power cable, the proposed ring-shaped receiver is designed to easily open or close using a clothespin-shaped handle, which is made of highly-insulated plastic. Laminated silicon steel plates are assembled and used as the core because of their mechanical robustness and high saturation flux density characteristic, in which the thickness of each isolated plate is 0.3 mm. The series-connected resonant capacitor, which is appropriate for low-voltage applications, is used together with the proposed receiver coil. The concept of the figure of merit, which is the product weight and cost of both the silicon steel plate and the copper wire, is used for an optimized design; therefore, the weight of the fabricated receiver and the price of raw material is 750 gf and USD $2 each, respectively. The 2.2 W powering capability of the fabricated receiver was experimentally verified with a power cable current of $100A_{rms}$ at 60Hz.

Trust and Health: Mind-Body Problem or Integrative Medicine (신뢰와 건강)

  • ChongNak Son
    • Korean Journal of Culture and Social Issue
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    • v.11 no.spc
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    • pp.85-95
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    • 2005
  • The present article explored the studies on the relational mechanisms between trust and health in terms of psychosomatic medicine or integrative medicine. For this, the research findings of the Quantum physics, psychosomatic medicine, and traditional eastern healing methods on the mind-body problem and then a practical guide to greater physical and mental well-being is presented. In the first section of the Quantum mechanical human body, the body has a mind of its own, the mechanism and cause of disease, the body as objective experienced conscious, and the effects of consciousness and information on the body are includes. The second section is psychosomatic medicine. In this, the thought changing brain, placebo, the power of expectancy, achieving health by active endeavor, psychoneuroimmunology, and the several therapies are included. Finally, Dr. Benson and Proctor's practical guide to well-being in presented. It is emphasized that the four trusts (trust in oneself, one's doctor, one's treatment, and one's spiritual trust) are crucial to recovery from serious illness and to achieve better health.

A study on an analysis of the impedance matching efficiency of 100 GHz band waveguide - type SIS mixer (100 GHz 대역 도파관형 SIS 믹서의 임피던스 정합 효율에 관한 해석)

  • 한석태;김효령;이창훈;박종애;정현수;김광동;김태성;박동철
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.33A no.6
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    • pp.81-89
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    • 1996
  • Quantum RF impedance of SIS (superconductor insulator superconductor) junction has been analyzed by using through on tucker's quantum mixer theory in the frequency range form 80 GHz to 120 GHz. The embedding impedance of waveguide-type mixer mount and its equivalent circuit have been evaluated. From these evaluated results, the impedance matching efficiency between mixer mount embedding impedance and mixer port impedance of upper-side band and IF which were determined by augmented admittance matrix with given backshort position has been discussed in detail. It is found that the mixer with fixed backshort mount ahs a impedance matching efficiency about 80% at each port of mixer within 85GHz to 115GHz, which implys a conversion los of mixer would be good enough to be operated such a wide band frequency range. Therefore, the theoretical evaluated results show that our method can be used ot design the mixer mount without any mechanical tuning elements such a backshort or an E-plane tunners for wide band operation.

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An Amber Force Field for S-Nitrosoethanethiol That Is Transferable to S-Nitrosocysteine

  • Han, Sang-Hwa
    • Bulletin of the Korean Chemical Society
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    • v.31 no.10
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    • pp.2903-2908
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    • 2010
  • Protein S-nitrosation is common in cells under nitrosative stress. In order to model proteins with S-nitrosocysteine (CysSNO) residues, we first developed an Amber force field for S-nitrosoethanethiol (EtSNO) and then transferred it to CysSNO. Partial atomic charges for EtSNO and CysSNO were obtained by a restrained electrostatic potential approach to be compatible with the Amber-99 force field. The force field parameters for bonds and angles in EtSNO were obtained from a generalized Amber force field (GAFF) by running the Antechamber module of the Amber software package. The GAFF parameters for the CC-SN and CS-NO dihedrals were not accurate and thus determined anew. The CC-SN and CS-NO torsional energy profiles of EtSNO were calculated quantum mechanically at the level of B3LYP/cc-pVTZ//HF/6-$31G^*$. Torsional force constants were obtained by fitting the theoretical torsional energies with those obtained from molecular mechanics energy minimization. These parameters for EtSNO reproduced, to a reasonable accuracy, the corresponding torsional energy profiles of the capped tripeptide ACE-CysSNO-NME as well as their structures obtained from quantum mechanical geometry optimization. A molecular dynamics simulation of myoglobin with a CysSNO residue produced a well-behaved trajectory demonstrating that the parameters may be used in modeling other S-nitrosated proteins.

Importance of Accurate Charges in Binding Affinity Calculations: A Case of Neuraminidase Series

  • Park, Kichul;Sung, Nack Kyun;Cho, Art E.
    • Bulletin of the Korean Chemical Society
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    • v.34 no.2
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    • pp.545-548
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    • 2013
  • It has been shown that calculating atomic charges using quantum mechanical level theory greatly improves the accuracy of docking. A protocol was developed and shown to be effective. That this protocol works is just a manifestation of the fact that electrostatic interactions are important in protein-ligand binding. In order to investigate how the same protocol helps in prediction of binding affinities, we took a series of known cocrystal structures of influenza neuraminidase inhibitors with the receptor and performed docking with Glide SP, Glide XP, and QPLD, the last being a workflow that incorporates QM/MM calculations to replace the fixed atomic charges of force fields with quantum mechanically recalculated ones at a given docking pose, and predicted the binding affinities of each cocrystal. The correlation with experimental binding affinities considerably improved with QPLD compared to Glide SP/XP yielding $r^2$ = 0.83. The results suggest that for binding sites, such as that of neuraminidase, which are laden with hydrophilic residues, protocols such as QPLD which utilizes QM-based atomic charges can better predict the binding affinities.

Fast Fourier Transform Analysis of Welding Penetration Depth Using 2 kW CW Nd:YAG Laser Welding Machine

  • Kim, Do-Hyung;Chung, Chin-Man;Baik, Sung-Hoon;Kim, Koung-Suk;Kim, Jin-Tae
    • Journal of the Korean Society for Nondestructive Testing
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    • v.28 no.4
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    • pp.372-376
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    • 2008
  • We report experimental results on the correlations between welding penetration depth and the frequencies of the radiation from the welding pool. Various welding samples such as SUS304, brass, SUS316, etc. have been investigated with 2 kW CW Nd:YAG laser welding machine. The radiation signals from the plume generated by the interactions between the welding sample and laser with respect to the defocusing length was measured with fiber system collecting the plume signal. Analysis of the frequencies by using fast Fourier transform (FFT) shows that the penetration depth is deep as plume signal frequencies are low, shallow penetration depth for high frequencies. Frequencies up to 250 Hz for obtained signals can be analyzed with the discrete FFT. This is the useful method fur closed loop control of the laser power with respect to the welding penetration depth and is used for real time inspection of the welding quality.

Anomalous Real Space Charge Transfer through Thick Barrieres in GaAs/$Al_xGa_{1-x}$As Asymmetric Double Quantun Wells: $Al_xGa_{1-x}$As as a Percolating Barrier

  • Kim, D. S.;H. S. Ko;Kim, Y. M.;S. J. Rhee;Kim, W. S.;J. C. Woo;Park, H. J.;J. Ihm;D. H. Woo
    • Proceedings of the Optical Society of Korea Conference
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    • 1995.06a
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    • pp.127-137
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    • 1995
  • Anomalously large real space charge transfer through thick barries in GaAs asymmetric double quantum wells is studied by photoluminesence exitation. This inter-well excitonic transfer is very large when the barrier is the Al0.3Ga0.7As alloy, but disappears when the barrier is GaAs/AlAs digital alloy with an equivalent Al concentration of 0.28. These resilts combined with observed x and barrier thickness depence suggest that the spatial fluctuation of the atomic arrangment of Ga and Al in the alloy may be responsible for this transfer. This picture is supported by the quantum mechanical calculation in three dimensions which takes into account the side fluctuation effects.

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Combination of fuzzy models via economic management for city multi-spectral remote sensing nano imagery road target

  • Weihua Luo;Ahmed H. Janabi;Joffin Jose Ponnore;Hanadi Hakami;Hakim AL Garalleh;Riadh Marzouki;Yuanhui Yu;Hamid Assilzadeh
    • Advances in nano research
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    • v.16 no.6
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    • pp.531-548
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    • 2024
  • The study focuses on using remote sensing to gather data about the Earth's surface, particularly in urban environments, using satellites and aircraft-mounted sensors. It aims to develop a classification framework for road targets using multi-spectral imagery. By integrating Convolutional Neural Networks (CNNs) with XGBoost, the study seeks to enhance the accuracy and efficiency of road target identification, aiding urban infrastructure management and transportation planning. A novel aspect of the research is the incorporation of quantum sensors, which improve the resolution and sensitivity of the data. The model achieved high predictive accuracy with an MSE of 0.025, R-squared of 0.85, RMSE of 0.158, and MAE of 0.12. The CNN model showed excellent performance in road detection with 92% accuracy, 88% precision, 90% recall, and an f1-score of 89%. These results demonstrate the model's robustness and applicability in real-world urban planning scenarios, further enhanced by data augmentation and early stopping techniques.

Ab Initio Quantum Mechanical Studies of 1,2-, 1,3-Dioxetanes and 1,3-Cyclodisiloxane; Energetics, Molecular Structures, Vibrational Frequencies (1,2-, 1,3-dioxetanes, 그리고 1,3-cyclodisiloxane의 분자구조, 에너지와 진동주파수에 대한 순 이론 양자 역학적 연구)

  • Choi Kun-Sik Choi;Seung-Joon Kim
    • Journal of the Korean Chemical Society
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    • v.47 no.4
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    • pp.325-333
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    • 2003
  • The geometrical parameters, vibrational frequencies, and relative energies for 1,2-, 1,3-dioxetanes, and 1,3-cyclodisiloxane have been investigated using high level ab initio quantum mechanical techniques with large basis sets. The geometries have been optimized at the self-consistent field(SCF), the single and double excitation configuration interaction(CISD), the coupled cluster with single and double excitation(CCSD), and the CCSD with connected triple excitations[CCSD(T)] levels of theory. The highest level of theory employed in this study is TZ2P CCSD(T). Harmonic vibrational frequencies and IR intensities are also determined at the SCF level of theory with various basis sets and confirm that all the optimized geometries are true minima. Also zero-point vibrational energies have been considered to predict the dimerization energies for 1,2- and 1,3-isomers.