Journal articles: 'Optical ground wire'

1

Leeson, Jesse, Xiaoyi Bao, and Alain Côté. "Polarization dynamics in optical ground wire network." Applied Optics 48, no. 12 (April 13, 2009): 2214. http://dx.doi.org/10.1364/ao.48.002214.

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Ebrahimi, Esmaeil, Masoud Abdolhosseinpour, Davood Moradi, and Faramarz Ghelichi. "GUI Based Optimal Drumming Algorithm for Optical Ground Wire (OPGW) Cables." Universal Journal of Electrical and Electronic Engineering 1, no. 1 (June 2013): 1–5. http://dx.doi.org/10.13189/ujeee.2013.010101.

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3

Ghannoum, E., J. P. Chouteau, M. Miron, S. Yaacoub, and K. Yoshida. "Optical ground wire for Hydro-Quebec's telecommunication network." IEEE Transactions on Power Delivery 10, no. 4 (1995): 1724–30. http://dx.doi.org/10.1109/61.473388.

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Egamnazarov, Georgiy. "The Way of Reducing Current Values in Optical Ground Wires at Asymmetrical Faults on Overhead Transmission Lines." Electrical, Control and Communication Engineering 11, no. 1 (December 1, 2016): 13–20. http://dx.doi.org/10.1515/ecce-2016-0007.

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Abstract Given the fact that the installing costs of an optical ground wire on overhead lines directly depend on its cross-section, which in turn depends on the level of fault current it should withstand, in order to reduce these current values in the optical ground wire, I suggested performing its isolated descents from the end towers of the line with its transition to an optical cable. The research was carried out on the example of a 500 kV overhead line in the National Electric Power Grid. The Method of Symmetrical Components for calculating asymmetrical fault currents was not used; therefore, calculations were carried out on the base of presenting the line as a multi-wire system for the considered case as a five-wire system (optical ground wire, steel ground wire, and three phase wires). Such approach allows taking into account the initial asymmetry of the line parameters and modeling any kind of asymmetrical faults. The analyses of calculated results were performed. The conclusive evidence that the optical ground wire isolated descents from the end towers of the line give the possibility of reducing the level of maximal fault current distribution values in it and therefore its cross section, is presented.

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Parker, Henry F., Alan D. Privette, and Earl P. Harding. "Testing of Composite Overhead Ground Wire Containing Optical Fibers." IEEE Power Engineering Review PER-5, no. 6 (June 1985): 66. http://dx.doi.org/10.1109/mper.1985.5526664.

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Madge, R. C., J. S. Barrett, and C. G. Maurice. "Considerations for fault current testing of optical ground wire." IEEE Transactions on Power Delivery 7, no. 4 (1992): 1786–92. http://dx.doi.org/10.1109/61.156979.

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Parker, Henry, Alan Privette, and Earl Harding. "Testing of Composite Overhead Ground Wire Containing Optical Fibers." IEEE Transactions on Power Apparatus and Systems PAS-104, no. 6 (June 1985): 1564–70. http://dx.doi.org/10.1109/tpas.1985.319173.

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Miao Chunsheng, 苗春生. "Distributed Optical Fiber Vibration Sensing in Optical Fiber Composite Overhead Ground Wire." Laser & Optoelectronics Progress 55, no. 4 (2018): 040604. http://dx.doi.org/10.3788/lop55.040604.

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Grunvalds, R., A. Ciekurs, J. Porins, and A. Supe. "Evaluation of Fibre Lifetime in Optical Ground Wire Transmission Lines." Latvian Journal of Physics and Technical Sciences 54, no. 3 (June 27, 2017): 40–49. http://dx.doi.org/10.1515/lpts-2017-0019.

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Abstract In the research, measurements of polarisation mode dispersion of two OPGWs (optical ground wire transmission lines), in total four fibres, have been carried out, and the expected lifetime of the infrastructure has been assessed on the basis of these measurements. The cables under consideration were installed in 1995 and 2011, respectively. Measurements have shown that polarisation mode dispersion values for cable installed in 1995 are four times higher than that for cable installed in 2011, which could mainly be explained by technological differences in fibre production and lower fibre polarisation mode dispersion requirements in 1995 due to lack of high-speed (over 10 Gbit/s) optical transmission systems. The calculation methodology of non-refusal work and refusal probabilities, using the measured polarisation mode dispersion parameters, is proposed in the paper. Based on reliability calculations, the expected lifetime is then predicted, showing that all measured fibres most likely will be operational within minimum theoretical service life of 25 years accepted by the industry.

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Roshan Fekr, M., G. McClure, and M. Farzaneh. "Application of ADINA to stress analysis of an optical ground wire." Computers & Structures 72, no. 1-3 (July 1999): 301–16. http://dx.doi.org/10.1016/s0045-7949(99)00037-1.

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IKEDA, Kensuke, Christina LIM, Ampalavanapillai NIRMALATHAS, and Chathurika RANAWEERA. "Comparison of Optical Transport Technologies for Centralized Radio Access Network Using Optical Ground Wire." IEICE Transactions on Communications E103.B, no. 11 (November 1, 2020): 1240–48. http://dx.doi.org/10.1587/transcom.2019obp0004.

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Yifeng, Fan, Li Xingzhou, Liu Chengyuan’, Jing Yihang, and Li Xudong. "Calculation and Analysis of Induced Current in Optical Fiber Composite Overhead Ground Wire." Journal of Physics: Conference Series 1887, no. 1 (June 1, 2021): 012022. http://dx.doi.org/10.1088/1742-6596/1887/1/012022.

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Ye Xuhui, 叶旭辉, 吴功平 Wu Gongping, 黄乐 Huang Le, and 樊飞 Fan Fei. "Field Ground Wire Detection Algorithm Based on Off-Line Learning Method." Acta Optica Sinica 38, no. 9 (2018): 0915001. http://dx.doi.org/10.3788/aos201838.0915001.

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Jiang, Xingliang, Yuqing Lei, Zhigao Meng, Jianlin Hu, and Zhijin Zhang. "DC ice-melting and temperature variation of optical fibre for ice-covered overhead ground wire." IET Generation, Transmission & Distribution 10, no. 2 (February 4, 2016): 352–58. http://dx.doi.org/10.1049/iet-gtd.2015.0324.

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Dubovan, Jozef, Jan Litvik, Daniel Benedikovic, Jarmila Mullerova, Ivan Glesk, Andrej Veselovsky, and Milan Dado. "Impact of Wind Gust on High-Speed Characteristics of Polarization Mode Dispersion in Optical Power Ground Wire Cables." Sensors 20, no. 24 (December 11, 2020): 7110. http://dx.doi.org/10.3390/s20247110.

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Polarization mode dispersion is recognized as a key factor limiting optical transmission systems, particularly those fiber links that run at bit rates beyond 10 Gbps. In-line test and characterization of polarization mode dispersion are thus of critical importance to evaluate the quality of installed optical fibers that are in use for high-speed signal traffics. However, polarization-based effects in optical fibers are stochastic and quite sensitive to a range of environmental changes, including optical cable movements. This, in turn, gives rise to undesired variations in light polarization that adversely impair the quality of the signal transmission in the link. In this work, we elaborate on experimental testing and theoretical analysis to asses changes of polarization mode dispersion in optical fibers that are caused by environmental variations, here wind gusts in particular. The study was performed on commercially harnessed optical fibers installed within optical power ground wire cables, taking into account different weather conditions. More specifically, we showed that changes caused by wind gusts significantly influence the differential group delay and the principal state of polarization in those optical fibers. For this, we experimentally measured a number of parameters to characterize light polarization properties. Measurements were carried out on C-band operated fiber-optic link formed by 111-km-long power ground wire cables and 88 spectral channels, with a test time step of 1 min during 12 consecutive days. Variations in differential group delay allowed for sensitive testing of environmental changes with measured maxims up to 10 ps under the worst wind conditions. Moreover, measured parameters were used in a numerical model to assess the quality of transmitted high-bit-rate optical signals as a function of wind conditions. The analysis revealed a negligible impact of wind on a 10 Gbps transmission, while substantial influence was noticed for higher bit rates up to 100 Gbps. These results show promises for efficient sensing of environmental changes and subsequent monitoring of the quality of recently used fiber-optic link infrastructures.

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Dmitriev, Victor, and Luciana Gonzalez. "Electrical and thermal analysis on optical ground wire cables in short-circuit regime by coupled equations." Electric Power Systems Research 101 (August 2013): 80–87. http://dx.doi.org/10.1016/j.epsr.2013.03.015.

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17

Xia Meng, 夏猛, 汤晓惠 Tang Xiaohui, 王颖 Wang Ying, 张书林 Zhang Shulin, 姜辉 Jiang Hui, and 董永康 Dong Yongkang. "Comparative Analysis of Strain Monitoring of the Installed Optical Fiber Composite Overhead Ground Wire Using BOTDA/R." Acta Optica Sinica 40, no. 15 (2020): 1506001. http://dx.doi.org/10.3788/aos202040.1506001.

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18

Assila, Labhib, Jean-Marc Ribero, Robert Staraj, and Jean-Lou Dubard. "Low-profile GSM-DCS-PCS-UMTS wire patch antenna on small ground plane." Microwave and Optical Technology Letters 51, no. 5 (March 13, 2009): 1247–50. http://dx.doi.org/10.1002/mop.24327.

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19

Shi, Teng, Howard E. Jackson, Leigh Morris Smith, Jan M. Yarrison-Rice, Bryan Wong, Joanne Etheridge, Nian Jiang, Qiang Gao, Hark Hoe Tan, and Chennupati Jagadish. "Localization of Excitons in Thin Core-Multi-Shell Quantum Well Tubes." MRS Proceedings 1659 (2014): 135–38. http://dx.doi.org/10.1557/opl.2014.357.

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ABSTRACTRecently, Fickenscher et al. [1] have shown that, in a core-multi-shell structure where a GaAs quantum well is embedded into an AlGaAs shell wrapped around a [111] oriented GaAs nanowire, the electron and hole ground states are strongly confined to the corners of the hexagonally symmetric quantum well. Thus this confinement defines quantum wires which run along the length of the nanowires along its corners. Here we review single nanowire photoluminescence measurements which show the significant confinement energy of the excitons. For well widths larger than 5 nm, optical transitions between electron and hole excited states can be seen in excitation spectra, while for widths less than 5 nm only the ground state optical transitions are observed. For well widths smaller than 5 nm, high resolution spatially resolved photoluminescence measurements show directly the appearance of localized states. Single nanowire spectra from the 4 nm QWT sample display ultranarrow emission lines on the high energy side of the luminescence band. Spatially-resolved PL images show that these quantum dots are localized randomly along the length of the wire.

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Pociask, Elżbieta, Krzysztof Piotr Malinowski, Magdalena Ślęzak, Joanna Jaworek-Korjakowska, Wojciech Wojakowski, and Tomasz Roleder. "Fully Automated Lumen Segmentation Method for Intracoronary Optical Coherence Tomography." Journal of Healthcare Engineering 2018 (December 26, 2018): 1–13. http://dx.doi.org/10.1155/2018/1414076.

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Background. Optical coherence tomography (OCT) is an innovative imaging technique that generates high-resolution intracoronary images. In the last few years, the need for more precise analysis regarding coronary artery disease to achieve optimal treatment has made intravascular imaging an area of primary importance in interventional cardiology. One of the main challenges in OCT image analysis is the accurate detection of lumen which is significant for the further prognosis. Method. In this research, we present a new approach to the segmentation of lumen in OCT images. The proposed work is focused on designing an efficient automatic algorithm containing the following steps: preprocessing (artifacts removal: speckle noise, circular rings, and guide wire), conversion between polar and Cartesian coordinates, and segmentation algorithm. Results. The implemented method was tasted on 667 OCT frames. The lumen border was extracted with a high correlation compared to the ground truth: 0.97 ICC (0.97–0.98). Conclusions. Proposed algorithm allows for fully automated lumen segmentation on optical coherence tomography images. This tool may be applied to automated quantitative lumen analysis.

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Cai, Li, Tianxi Han, Jianguo Wang, Jian Xue, Fei Xu, Mi Zhou, and Yadong Fan. "Experimental analysis of the strands breaking characteristics of optical fibre composite overhead ground wire due to simulating lightning strike." IET Generation, Transmission & Distribution 14, no. 15 (August 3, 2020): 2922–29. http://dx.doi.org/10.1049/iet-gtd.2019.1826.

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22

Chou, Jui-Hung, and Saou-Wen Su. "Matching a Bluetooth headset antenna on a small system ground by using a conductive wire." Microwave and Optical Technology Letters 51, no. 12 (September 23, 2009): 2802–5. http://dx.doi.org/10.1002/mop.24755.

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Huang, Hongxia, Lin Li, and Zhibin Zhao. "A fast algorithm for computing electromagnetic fields of a thin wire current source inside lossy ground." Frontiers of Electrical and Electronic Engineering in China 5, no. 2 (April 29, 2010): 224–28. http://dx.doi.org/10.1007/s11460-010-0016-z.

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Campione, Salvatore, Larry Kevin Warne, Matthew Halligan, Olga Lavrova, and Luis San Martin. "DECAY LENGTH ESTIMATION OF SINGLE-, TWO-, AND THREE-WIRE SYSTEMS ABOVE GROUND UNDER HEMP EXCITATION." Progress In Electromagnetics Research B 84 (2019): 23–42. http://dx.doi.org/10.2528/pierb19010803.

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Peter, A. J., and N. Radhakrishnan. "Polaronic Effects of a Hydrogenic Donor Impurity in Low Dimensional Semiconductor Systems." Journal of Scientific Research 1, no. 3 (August 29, 2009): 422–29. http://dx.doi.org/10.3329/jsr.v1i3.2529.

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The ground state of a polaron bound to hydrogen like donor impurity is investigated by considering the effect of bulk Longitudinal-Optical (LO) phonon. Donor binding energy of a hydrogenic donor, with the inclusion of electron-phonon interaction is computed for the low-dimensional semiconducting systems like quantum well, quantum well wire and quantum dot taking GaAs/AlxGa1-xAs systems as an example. Calculations are performed using a variational approach within the single band effective mass approximation. The results show that the polaronic effect is more pronounced for the lowest confinement. The polaronic effect enhances the donor binding energy but it diminishes when the well width, wire radius and dot radius become larger. Also the numerical calculations reveal that the influences of phonons on donor are considerable and should not be neglected especially for narrow dimensions in all the three confinements.Keywords: Donor binding energy; Polaronic effect; Quantum dot; Quantum wire; Quantum well.© 2009 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.DOI: 10.3329/jsr.v1i3.2529 J. Sci. Res. 1 (3), 422- 429 (2009)

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Yeranosyan, Mkrtich A., Abbas Ghouchani Shahbandari, and Arshak L. Vartanian. "The Phonon Confinement Effect on the Impurity States in Cylindrical Nanowire with a Finite Confining Potential in Presence of Electric and Magnetic Fields." Advanced Materials Research 829 (November 2013): 795–99. http://dx.doi.org/10.4028/www.scientific.net/amr.829.795.

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In the framework of effective mass approximation, the LandauPekar variational procedure is adopted to study the ground-state binding energy of a hydrogenic impurity in a semiconductor nanowire with finite confining potential subjected to both external fields (electric and magnetic) and electronpolar optical phonon interaction taking into account the phonon confinement effect. The results for the binding energy as well as polaronic correction are obtained as a function of the wire radius, impurity position and applied fields. Calculated results reveal that the values of the polaronic shifts of impurity binding energy can be quite different for cases with finite and infinite confining potentials.

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27

Mollet, Christian, Angela Kunoth, and Torsten Meier. "Excitonic Eigenstates of Disordered Semiconductor Quantum Wires: Adaptive Wavelet Computation of Eigenvalues for the Electron-Hole Schrödinger Equation." Communications in Computational Physics 14, no. 1 (July 2013): 21–47. http://dx.doi.org/10.4208/cicp.081011.260712a.

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AbstractA novel adaptive approach to compute the eigenenergies and eigenfunctions of the two-particle (electron-hole) Schrödinger equation including Coulomb attraction is presented. As an example, we analyze the energetically lowest exciton state of a thin one-dimensional semiconductor quantum wire in the presence of disorder which arises from the non-smooth interface between the wire and surrounding material. The eigenvalues of the corresponding Schrödinger equation, i.e., the one-dimensional exciton Wannier equation with disorder, correspond to the energies of excitons in the quantum wire. The wavefunctions, in turn, provide information on the optical properties of the wire.We reformulate the problem of two interacting particles that both can move in one dimension as a stationary eigenvalue problem with two spacial dimensions in an appropriate weak form whose bilinear form is arranged to be symmetric, continuous, and coercive. The disorder of the wire is modelled by adding a potential in the Hamiltonian which is generated by normally distributed random numbers. The numerical solution of this problem is based on adaptive wavelets. Our scheme allows for a convergence proof of the resulting scheme together with complexity estimates. Numerical examples demonstrate the behavior of the smallest eigenvalue, the ground state energies of the exciton, together with the eigenstates depending on the strength and spatial correlation of disorder.

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CHAO, KAI-YUAN, and D. F. WONG. "FLOORPLAN DESIGN WITH LOW POWER CONSIDERATIONS." International Journal of High Speed Electronics and Systems 07, no. 02 (June 1996): 305–22. http://dx.doi.org/10.1142/s012915649600013x.

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In this paper, a floorplanner for low power design is presented. Our objective is to optimize total power consumption and area during the selection and placement of various implementations for circuit modules. Furthermore, the proposed method considers performance requirements, power line noises, and distribution of power consumption in order to generate lower and evenly distributed power dissipation over the resulting circuit floorplan with a specified performance. For a set of benchmark circuits we tested, on the average, our floorplanner can achieve decreases of total power consumption, wire-length, and power/ground network size by 18.3%, 4.6%, and 24%, respectively, at the cost of an area increase of 8.8% when compared with an existing area/wire-length driven floorplanner.

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Brand�o Faria, J. A. "A perturbation approach for evaluating the wave parameters of a wire above a nonhomogeneous ground with longitudinally random characteristics." Microwave and Optical Technology Letters 26, no. 3 (2000): 166–69. http://dx.doi.org/10.1002/1098-2760(20000805)26:3<166::aid-mop9>3.0.co;2-x.

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Li, Xiangxin, Ming Zhou, Yazhou Luo, Chao Xia, Bin Cao, and Xiujuan Chen. "Insulation Reconstruction for OPGW DC De-Icing and Its Influence on Lightning Protection and Energy Conservation." Energies 11, no. 9 (September 14, 2018): 2441. http://dx.doi.org/10.3390/en11092441.

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In order to satisfy demands for DC de-icing of optical fiber composite overhead ground wire (OPGW) and solve questions such as those relating to circulating current loss and liability of suffering from lightning strike, the grounding method of OPGW must be changed from the current commonly used method of being grounded at every tower to being grounded at one tower. The OPGW would be connected to the tower by an insulator, which is often shunt connected with a protective discharge clearance. The recommended value of the discharge clearance is from 70 to 80 mm. The lightning impulse discharge voltage of such a clearance is generally not more than 100 kV. However, as the transmission line is struck by lightning, over-voltage on the clearance is 885 kV at least, even up to a few MV. The clearance can be broken down reliably. The influence of insulation reconstruction for OPGW on the induced current and the power loss of the AC transmission line was studied by means of theoretical analysis and simulation calculations. Results indicate that change of the OPGW grounding mode could reduce the induced current of the ground wire to below 1 A and reduce the power loss of the line to below 1 W/km. Power loss could be reduced by over 99%. Adoption of a suitable grounding mode for OPGW is of great significance for DC de-icing, lightning protection safety, and energy savings for UHV projects.

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Papaioannou, D. A., and J. N. Avaritsiotis. "Simulation of Crosstalk in High-Speed Multi-Chip Modules." Active and Passive Electronic Components 17, no. 4 (1995): 283–96. http://dx.doi.org/10.1155/1995/24575.

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Simulation results of the electrical performance at 1 GBits/sec of a number of different off-chip interconnection architectures are presented with emphasis given to the dependence of crosstalk and signal delay on the geometries and dielectric constants of the insulating layers as well as on the widths and separations of the conductors. The results indicate that signal delay and crosstalk may be reduced by using lowεrvalues for the dielectrics and that crosstalk may be also reduced by reducing the conductor-to-ground wire separation which simultaneously neutralises the role ofεrvalue on crosstalk and line impedance.

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32

Wada, Kazumi. "Cathodoluminescence characterization of two-dimensional interface structure of quantum wells." Proceedings, annual meeting, Electron Microscopy Society of America 48, no. 4 (August 1990): 754–55. http://dx.doi.org/10.1017/s0424820100176903.

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Exotic properties shown by quantum well structures, typical structures of future electron devices, are sensitive to interface roughness. Extensive studies are, thus, focused on characterization of interface structures. Recent improvement in quantum wire fabrication technology demands for characterizing not only perpendicular-interfaces to the growth direction but also parallel-ones (sidewall-interfaces). Such sophistication needs innovation in two-dimensional and nondestructive characterization technology.In device structures, interfaces are generally located deep in bulk. STM which visualize surface atoms can not monitor such interface. It is, thus, difficult to two- dimensionally characterize the interfaces.Interface steps induce well width fluctuation, which modulates optical transition energy between ground subbands in conduction and valence bands. Thus, interface step structures can be characterized by luminescence spectroscopy. Cathodoluminescence basically meets demand for nondestructive characterization of interface structures in two dimensions.

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33

Vartanian, Arshak L., Mkrtich A. Yeranosyan, and Albert A. Kirakosyan. "Electron–phonon effect on the ground-state binding energy of hydrogenic impurity in quantum-well wire in presence of an electric field." Physica B: Condensed Matter 390, no. 1-2 (March 2007): 256–62. http://dx.doi.org/10.1016/j.physb.2006.08.022.

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Girardi, M. A., K. A. Peterson, P. T. Vianco, R. Grondin, and D. Wieliczka. "Laser Ablation of Thin Films on Low Temperature Cofired Ceramic." Journal of Microelectronics and Electronic Packaging 12, no. 2 (August 1, 2015): 72–79. http://dx.doi.org/10.4071/imaps.457.

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Direct digital manufacturing techniques such as laser ablation are proposed for the fabrication of lower cost, miniaturized, and lightweight integrated assemblies with high performance requirements. This paper investigates the laser ablation of a Ti/Cu/Pt/Au thin-film metal stack on fired low temperature cofired ceramic (LTCC) surfaces using a 355-nm Nd:YAG diode-pumped laser ablation system. It further investigates laser ablation applications using unfired, or “green,” LTCC materials in the following ways: (1) through one layer of a laminated stack of unfired LTCC tape to a buried thick-film-conductor ground plane, and (2) in unfired Au thick films. The UV-laser power profile and part fixturing were optimized to address defects such as LTCC microcracking, thin-film adhesion failures, and redeposition of Cu and Pt. An alternate design approach to minimize ablation time was tested for efficiency in manufacture. Multichip modules were tested for solderability, solder leach resistance, and wire bondability. Scanning electron microscopy, as well as cross sections and microanalytical techniques, were used in this study.

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KOROLEV, ANDREI V., and MICHAEL A. LIBERMAN. "EXCITONS IN A HIGH MAGNETIC FIELD." International Journal of Modern Physics B 10, no. 07 (March 30, 1996): 729–75. http://dx.doi.org/10.1142/s0217979296000313.

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A high magnetic field, such that the distance between the Landau levels exceeds the binding energy of an exciton, gives an opportunity to create various new states of matter, i.e. exciton crystal, molecular compexes, Bose–Einstein condensation an exciton gas in a semiconductor, depending on the dimensionality of the system. We consider the problem of excitonic interaction in a semiconductor in its multi-electron formulation, starting from the second-quantization representation of the Hamiltonian of interacting electrons and holes in a high magnetic field. A system of excitons in its ground state in a high magnetic field is similar to a weakly non-ideal Bose gas; whereas the excited states may be strongly bounded. It is shown that different types of exciton complexes in a quasi-one-dimensional semiconductor quantum wire, from crystals to molecular chains, can be obtained both by varying the direction and intensity of the magnetic field and by changing the exciton density. The existence and the stability of the Bose condensate in a bulk semiconductor due to an essential decrease of the interaction between excitons and an increase of their binding energy in a high magnetic field are established at a high density of excitons. Existence of the built-in condensate of excitons in a broad density range significantly changes the excitation spectrum of coupled excitons and photons in a high magnetic field and results in a number of interesting optical phenomena.

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Contreras Corona, Nancy Nayeli, Frederic Trillaud, and Felix Rosendo Poy Segura. "Direct current lightning tests on Optical Ground Wires." IEEE Latin America Transactions 13, no. 3 (March 2015): 640–44. http://dx.doi.org/10.1109/tla.2015.7069086.

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Lamarche, L., D. Gagnon, and M. Miron. "Long term attenuation measurements on optical ground wires." IEEE Transactions on Power Systems 11, no. 4 (1996): 1863–67. http://dx.doi.org/10.1109/59.544655.

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38

Khodadadi, A., M. H. Nazari, and S. H. Hosseinian. "Designing an Optimal Lightning Protection Scheme for Substations Using Shielding Wires." Engineering, Technology & Applied Science Research 7, no. 3 (June 12, 2017): 1595–99. http://dx.doi.org/10.48084/etasr.1175.

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An optimal lightning protection scheme for a substation using shielding wires is investigated in this paper through computer software analysis. An economic approach is utilized by choosing a reasonable trade-off between protection, the number of shielding wires and the heights of them from the ground. This study is initially applied to a simple two-wire system and then extended to a sample substation. The solution for each problem is executed in MATLAB and 3-D realization is shown.

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Madge, R. C., S. Barrett, and H. Grad. "Performance of optical ground wires during fault current tests." IEEE Transactions on Power Delivery 4, no. 3 (July 1989): 1552–59. http://dx.doi.org/10.1109/61.32642.

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40

Madge, R. C., S. Barrett, and H. Grad. "Performance of Optical Ground Wires During Fault Current Tests." IEEE Power Engineering Review 9, no. 7 (1989): 39–40. http://dx.doi.org/10.1109/mper.1989.4310787.

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41

Sun, Jinru, Xueling Yao, Wenjun Xu, Xiangyu Tian, and Jingliang Chen. "Lightning Test Method for Optical-Fiber Overhead Ground Wires." IEEE Transactions on Power Delivery 33, no. 5 (October 2018): 2412–19. http://dx.doi.org/10.1109/tpwrd.2018.2823061.

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Cao, Dingfeng, Hongyuan Fang, Fuming Wang, Honghu Zhu, and Mengya Sun. "A Fiber Bragg-Grating-Based Miniature Sensor for the Fast Detection of Soil Moisture Profiles in Highway Slopes and Subgrades." Sensors 18, no. 12 (December 14, 2018): 4431. http://dx.doi.org/10.3390/s18124431.

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A fiber Bragg grating (FBG)-based aluminum oxide tube packed sensor (ATPS) was developed for the fast detection of the soil moisture profile in highway slopes and subgrades. The novel ATPS consists of an aluminum oxide tube with a diameter of 5 mm, an optical fiber containing a quasi-distributed FBG sensors, a “U”-shaped resistance wire, and a flange. There are four 0.9-mm diameter holes in the ATPS. Laboratory experiments were carried out to calibrate the relationship between the thermal response of ATPS and the soil moisture content. Two laboratory rainfall validation model tests were performed to validate the ATPS for capturing the soil moisture profile in highway slopes and subgrades. During the validations, the accuracy of the ATPS was quantified, and water infiltration through grassy and grassless ground surfaces were investigated. The calibrations indicate that the ATPS can detect and record real-time changes in the highway slope and subgrade moisture after rainfall, and reveal the most dangerous zones that occur at the connection between different construction materials. The average measurement accuracy of soil moisture monitoring was 0.015 m3/m3. Please note that the connection is where cracks form easily and the soil hydraulic conductivity increases significantly. The test results also indicate that grassy cover (lawn) significantly prevents water infiltration during the first few minutes of rainfall (twelve minutes in this study), after which, however, the infiltration rate drops sharply. The influence of lawn on water infiltration depends on the soil structure, hydraulic conductivity, and rainfall time. In summary, due to its small size and fast detection, the ATPS is a portable probe that can be used for moisture monitoring in highway slopes and subgrades.

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Przondziono, Joanna, and Witold Walke. "Resistance to Electrochemical Corrosion under Conditions of Sterilisation of Guide Wires Used in Endourological Treatment." Solid State Phenomena 212 (December 2013): 163–66. http://dx.doi.org/10.4028/www.scientific.net/ssp.212.163.

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The influence of surface modification and steam sterilisation process on the corrosion characteristics of wires made of X10CrNi18-8 steel used for production of guide wires in endourological treatment was analysed in the study. Corrosion tests were made in artificial urine solution with application of electrochemical testing system VoltaLab PGP201. Resistance to pitting corrosion was evaluated on the ground of registered anodic polarisation curves by means of potentiodynamic method. The tests comprised wires with surface that was ground, electrochemically polished and chemically passivated. Steam sterilisation was performed in autoclave Basic Plus by Mocom. The tests proved that surface modification improved corrosion characteristics of the wire to a great extent. The best corrosion resistance in artificial urine was observed in wire whose surface was successively ground, polished and chemically passivated. It was also proved that chemical passivation process has a favourable impact on corrosion resistance improvement under sterilisation conditions.

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Bayliss, S. L., D. W. Laorenza, P. J. Mintun, B. D. Kovos, D. E. Freedman, and D. D. Awschalom. "Optically addressable molecular spins for quantum information processing." Science 370, no. 6522 (November 12, 2020): 1309–12. http://dx.doi.org/10.1126/science.abb9352.

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Spin-bearing molecules are promising building blocks for quantum technologies as they can be chemically tuned, assembled into scalable arrays, and readily incorporated into diverse device architectures. In molecular systems, optically addressing ground-state spins would enable a wide range of applications in quantum information science, as has been demonstrated for solid-state defects. However, this important functionality has remained elusive for molecules. Here, we demonstrate such optical addressability in a series of synthesized organometallic, chromium(IV) molecules. These compounds display a ground-state spin that can be initialized and read out using light and coherently manipulated with microwaves. In addition, through atomistic modification of the molecular structure, we vary the spin and optical properties of these compounds, indicating promise for designer quantum systems synthesized from the bottom-up.

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Hutter, Donald J. "The Accuracy of Ground-Based Optical Interferometry Observations." International Astronomical Union Colloquium 180 (March 2000): 47–56. http://dx.doi.org/10.1017/s0252921100000099.

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AbstractThe problem of wide-angle astrometry via interferometry is to recover the two coordinates for each star from the observed delays. In the absence of atmospheric turbulence, the geometrical delay can be defined as: dG, ij(t) ≡ dj(t) ‒ di(t) = Bij(t)·ŝ0 ‒ Cij. Here the geometrical delay is the difference between the delay line lengths di and dj that is required to equalize the effective optical paths from the star to the point of beam combination via each of two apertures i and j. Bij(t) is the baseline between the apertures, ŝ0 is the star position, and Cij is the difference between the ‘fixed’ internal optical path lengths Ci and Cj within the instrument. In principle, sufficient delay measurements would allow solution for the baseline vectors and the delay constants, as well as the positions of the stars. However, the actual situation is greatly complicated by the presence of the atmosphere and the fact that neither the delay ‘constants’ Cij nor the baseline vectors are stable over time. The design of, and the analysis of the data from, any ground-based optical interferometer must overcome all three of these effects. The design, operation, and the analysis of data from the Navy Prototype Optical Interferometer (NPOI) are presented here as examples of how to overcome the effects of the atmosphere and the instrumental instabilities in order to achieve accurate wide-angle astrometry. The status of the implementation of these techniques at the NPOI is presented.

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Rhudy, Matthew B., Yu Gu, Haiyang Chao, and Jason N. Gross. "Unmanned Aerial Vehicle Navigation Using Wide-Field Optical Flow and Inertial Sensors." Journal of Robotics 2015 (2015): 1–12. http://dx.doi.org/10.1155/2015/251379.

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This paper offers a set of novel navigation techniques that rely on the use of inertial sensors and wide-field optical flow information. The aircraft ground velocity and attitude states are estimated with an Unscented Information Filter (UIF) and are evaluated with respect to two sets of experimental flight data collected from an Unmanned Aerial Vehicle (UAV). Two different formulations are proposed, a full state formulation including velocity and attitude and a simplified formulation which assumes that the lateral and vertical velocity of the aircraft are negligible. An additional state is also considered within each formulation to recover the image distance which can be measured using a laser rangefinder. The results demonstrate that the full state formulation is able to estimate the aircraft ground velocity to within 1.3 m/s of a GPS receiver solution used as reference “truth” and regulate attitude angles within 1.4 degrees standard deviation of error for both sets of flight data.

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McLoughlin, Benjamin, Harry Pointon, John McLoughlin, Andy Shaw, and Frederic Bezombes. "Uncertainty Characterisation of Mobile Robot Localisation Techniques using Optical Surveying Grade Instruments." Sensors 18, no. 7 (July 13, 2018): 2274. http://dx.doi.org/10.3390/s18072274.

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Recent developments in localisation systems for autonomous robotic technology have been a driving factor in the deployment of robots in a wide variety of environments. Estimating sensor measurement noise is an essential factor when producing uncertainty models for state-of-the-art robotic positioning systems. In this paper, a surveying grade optical instrument in the form of a Trimble S7 Robotic Total Station is utilised to dynamically characterise the error of positioning sensors of a ground based unmanned robot. The error characteristics are used as inputs into the construction of a Localisation Extended Kalman Filter which fuses Pozyx Ultra-wideband range measurements with odometry to obtain an optimal position estimation, all whilst using the path generated from the remote tracking feature of the Robotic Total Station as a ground truth metric. Experiments show that the proposed method yields an improved positional estimation compared to the Pozyx systems’ native firmware algorithm as well as producing a smoother trajectory.

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Black, W. Z., and M. G. Wells. "Temperature rise of optical fiber ground wires subjected to short duration-high current transients." IEEE Transactions on Power Delivery 4, no. 3 (July 1989): 1806–15. http://dx.doi.org/10.1109/61.32676.

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Black, W. Z., and M. Glen Wells. "Temperature Rise of Optical Fiber Ground Wires Subjected to Short Duration-High Current Transients." IEEE Power Engineering Review 9, no. 7 (1989): 66–67. http://dx.doi.org/10.1109/mper.1989.4310821.

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Pignari, Sergio A., and Giordano Spadacini. "Plane-Wave Coupling to a Twisted-Wire Pair Above Ground." IEEE Transactions on Electromagnetic Compatibility 53, no. 2 (May 2011): 508–23. http://dx.doi.org/10.1109/temc.2010.2061855.

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Journal articles on the topic 'Optical ground wire'

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