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[IEEE 2018 20th International Symposium on High-Current Electronics (ISHCE) - Tomsk, Russia (2018.9.16-2018.9.22)] 2018 20th International Symposium on High-Current Electronics (ISHCE) - Measurements of Sub-Nanosecond Pulsed Electromagnetic Waves by Strip-Line Sensors with Long Transmitting Coaxial Cable
摘要： Antennas of strip-line types with transmitting coaxial cable are presented as ultra-wideband sensors of the E(t)- field impulses in electromagnetic traveling-waves at free space. The cable of 1-10 m length produces noticeable attenuation and distortion of sub-nanosecond signals. Computer models of coaxial cables are given. A way to increase the sensor sensitivity for rapid signals to compensate of the cable losses is shown by simulated and experimental results. Considered laboratory antenna sensor of microstrip design with 4m cable length has 0.36 V/(kV/m) sensitivity, 50 ps rise-time and 4.2 ns time-gap.
关键词： sub-nanosecond pulsed electromagnetic waves,strip-line antenna sensor,transient responses of coaxial cables
更新于2025-09-23 15:21:21
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[IEEE 2018 IEEE 2nd International Conference on Dielectrics (ICD) - Budapest (2018.7.1-2018.7.5)] 2018 IEEE 2nd International Conference on Dielectrics (ICD) - Electric Field Enhancement from Semiconductive Protrusions in Extruded Power Cables
摘要： The paper deals with calculation of the field enhancement from semiconductive protrusions in high voltage polymeric cables. The scientific community has traditionally used two different equations: The Larmor formula assuming spheroidal shape of the protrusion and the Mason formula assuming hyperboloidal shape. The Larmor equation can only be used for sharp protrusions (small tip radius) that are not representative for the majority of the protrusions found in power cables. On the other hand, the Mason equation has not this restriction, but can give values very much different from those obtained by the Larmor formula. It will be emphasized in the paper that the Mason formula was derived for needle-plane geometries and is therefore not valid for estimation of the field enhancement of protrusions extending into the insulation from a conductive plane. On the other hand, the Larmor formula follows from the analytical solution of the Laplace equation for the electric field outside a spheroidal-shaped protrusion in a plane-plane geometry. It is thus the best available formula for calculating field enhancement from semiconductive protrusions in high voltage cables. The paper will also introduce a new solution to the Laplace equation making it possible to extend the Larmor equation to spheroidal protrusions of all shapes, including those typical for modern cables.
关键词： Power cables,field enhancement,protrusions
更新于2025-09-23 15:21:01
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An Improved Topography-Coupled Kernel-Driven Model for Land Surface Anisotropic Reflectance
摘要： G.fast is a new standard from the International Telecommunication Union, which targets 1 Gb/s over short copper loops using frequencies up to 212 MHz. This new technology requires accurate parametric cable models for simulation, design, and performance evaluation tests. Some existing copper cable models were designed for the very high speed digital subscriber line spectra, i.e., frequencies up to 30 MHz, and adopt assumptions that are violated when the frequency range is extended to G.fast frequencies. This paper introduces a simple and causal cable model that is able to accurately characterize copper loops composed by single or multiple segments, in both frequency and time domains. Results using G.fast topologies show that, apart from being accurate, the new model is attractive due to its low computational cost and closed-form expressions for fitting its parameters to measurement data.
关键词： transmission line theory,twisted-pair copper cables,G.fast,Cable models,digital subscriber line (DSL)
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE International Meeting for Future of Electron Devices, Kansai (IMFEDK) - Kyoto, Japan (2019.11.14-2019.11.15)] 2019 IEEE International Meeting for Future of Electron Devices, Kansai (IMFEDK) - Invited: Possibility of dye-sensitized solar cell as energy harvester
摘要： This paper proposes a statistical approach for section-based fault location in medium voltage (MV) grids with underground cables, using Bayesian inference. The proposed approach considers several important uncertainties in the MV grid, including measurement errors, fault breakdown resistance, and the inaccuracies of zero-sequence parameters. The approach first obtains the prior distribution of the fault position from the component failure database, the readings of the transmitted fault indicators, and the relevant digging activity record. With the estimated prefault grid status and the measured transient voltages/currents, the posterior distribution is then calculated based on Bayes’ theorem. To solve the problem numerically, the Monte Carlo integration is applied and a two-step calculation procedure is proposed. Simulations are performed on a typical European MV feeder to demonstrate the feasibility of the approach. The distribution grid operators can use the calculated posterior distribution to rank the possible faulted sections and to facilitate the restoration process, which can reduce the interruption duration of power supply.
关键词： transient measurements,section-based fault location,Monte Carlo integration,underground cables,Bayesian inference
更新于2025-09-16 10:30:52
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[IEEE 2019 IEEE International Conference on Image Processing (ICIP) - Taipei, Taiwan (2019.9.22-2019.9.25)] 2019 IEEE International Conference on Image Processing (ICIP) - Learning Lightweight Pedestrian Detector with Hierarchical Knowledge Distillation
摘要： In order to transfer 3000-MW capacity of electricity from the mine-mouth coal-fired power plants in South Sumatra to the load center in Java, PLN Indonesia intends to build the Java-Sumatra Power Interconnection System. The scopes of these works of the Power Interconnection System are including: high voltage alternating current (HVAC) 500 kV Transmission Line in Java, HVAC 500 kV Transmission Line in Sumatra, high voltage direct current (HVDC) 500 kV Transmission Line in Java, HVDC 500 kV Transmission Line in Sumatra, and HVDC 500 kV Java-Sumatra submarine cables. This paper will analyze the financial feasibility study to ensure whether the project has economic benefit, and the asset would be used effectively and efficiently along its benefit period using life cycle cost analysis (LCCA). In this paper, an LCCA will be simulated to analyze three alternatives and to decide which alternative is the most profitable. Monte Carlo simulations and a break-even chart for a period of 30 years' operation of the interconnection system are part of the LCCA models to achieve the objectives of this paper.
关键词： cost benefit analysis,underwater,decision making,Risk analysis,project engineering,power transmission,availability,maintenance,cables,reliability
更新于2025-09-16 10:30:52
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Compact pulsed intense magnetic field generator for Shenguang-II upgrade laser facility
摘要： A compact pulsed intense magnetic field generator is presented for magnetized laser plasma experiments at the Shenguang-II upgrade laser facility (Shanghai). The pulsed magnetic field device can generate a 45 kA peak current with 480 ns rising time at a discharge voltage of 40 kV, time jitter is about 100 ns. The peak magnetic field reaches 9 T using a double-twisted coil of 12 mm diameter. A specially designed tunable transmission line was developed to realize the flexible connection between the capacitor bank and the magnetic field coil. The setup is compatible with the particular target chamber of the laser facility. Thus the coil component can be adjusted separately by the three-dimensional motorized translation stage placed in the target chamber, with 10 cm (transverse) and 1 cm (longitudinal) adjustable scales and 6 μm precision. A high-voltage electric-trigger spark-gap gas switch was used to reduce the operation complexity and the occupied area of the generator. Grounding and shielding structure ensure fine electromagnetic compatibility with the target chamber. The device has been successfully operated in magnetized laser plasma experiments performed on the laser facility.
关键词： Special cables,Pulsed power,Plasma generation (laser-produced, RF, x ray-produced)
更新于2025-09-12 10:27:22
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Failure Analysis of Metallic Armoured Electro-Optic Mechanical Cables in Underwater Towed Sonar Systems
摘要： In towed sonar systems generally, the array is towed behind a ship using a combination of electro-optic mechanical (EOM) tow cables - negatively buoyant metallic armoured Heavy Cable and neutrally buoyant fibre armoured Light Cable- the former for depth control and latter for depth maintenance. Any failure in these cables can affect the performance of the sensor array and can even result in loss of the towed system to sea. During a series of towed array trials, it was observed that the metallic armoured cable had lost its circularity and became flattened during deployment and retrieval from ship. This may be due to the extreme radial forces acting on the cable while passing through a) rollers located at winch spooler and b) main fairlead comprising of 5 rollers located at aft end of ship, which causes permanent changes in cable’s internal configuration. To verify the cause and study the effects of such flattening on functionality and life of the cable, cyclic load testing studies were carried out after simulating the actual deployment-retrieval conditions as that in the ship. Both indigenously developed and imported cable samples were chosen as test samples for performance comparison. During the tests, it was observed that severe flattening of armour and core cable resulting in failure of electrical & optical lines had occurred in indigenous cable samples. The imported cable samples showed no flatness or failure of lines. Based on the results, steps were taken to improve the radial load bearing capacity of the indigenous cable. Modifications were made in a) core cable sheath material b) core cable sheath thickness & c) armour wire material and an improved indigenous cable was developed, which has withstood all the above tests and is now ready to be inducted to the system for sea trials.
关键词： Towed array sonar,Metallic armored cable,Electro-Optic Mechanical (EOM) tow cables,Cyclic load testing
更新于2025-09-12 10:27:22
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Distributed Fiber Sensing and Dynamic Rating of Power Cables || Optical Fibers, Connectors, and Cables
摘要： This chapter introduces the types of fibers available in the industry for DTS applications, the types of optical connectors, and their relevance in the context of distributed sensing applications. It also discusses how they may be incorporated into power cable transmission land and submarine corridors as well as the potential challenges that one may encounter during installation, particularly when fibers are embedded in the power cable itself.
关键词： Installation challenges,Connectors,Submarine corridors,DTS applications,Distributed sensing,Optical Fibers,Power cable transmission,Cables
更新于2025-09-11 14:15:04
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Photonic demultiplexer based on electromagnetically induced transparency resonances
摘要： We give an analytical and experimental demonstration of the possibility to realize a simple photonic demultiplexer based on electromagnetically induced transparency (EIT) resonances. The demultiplexer consists on an Y-shaped waveguide with an input line and two output lines. Each output line contains two grafted stubs at a given position far from the input line. We derive in closed form the expressions for a selective transfer of a single propagating mode through one line keeping the other line unaffected. We illustrate the analytical and numerical results by a simple experiment carried out using coaxial cables in the radio-frequency domain.
关键词： Coaxial cables,Y-shaped waveguide,EIT resonances,Photonic demultiplexer,Electromagnetically induced transparency
更新于2025-09-10 09:29:36