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This study has outlined the effects of physical parameters of erbium doped fiber amplifier (EDFA), semiconductor optical amplifier (SOA) on the performance of amplified soliton transmission systems. Injection current-based SOA, EDFA length is taken into account. It is observed that the optimum soliton power and signal per noise ratio are achieved with 5 m EDFA length and 900 mA injection current-based SOA. As well as the bit sequence variations based user defined bit sequence generator are employed in order to measure the soliton transmission system performance. The signal per noise ratio is enhanced with 4 bit sequence. Soliton peak power, output soliton power, and maximum Q-factor are optimized with 8 bit sequence for soliton propagation length of 150 km and possible transmission data rates of 160 Gb/s. Improvement percentage ratio in soliton peak power by using two amplification techniques a long propagation length is deeply stimulated with optiwave simulation program.

We propose and fabricate a monolithically integrated dual-mode semiconductor laser (DML) based on optical amplified feedback, where the adjustable optical self-injection feedback could induce dual-wavelength lasing, and the sub-millimeter total cavity length provides access to be microwave source. When keeping the injection current of semiconductor optical amplifier (SOA) be constant, inject different current for the segment of distributed feedback laser (DFB), we have achieved tunable microwave signal with different ranges of 10 GHz and 18 GHz respectively, which significantly simplifies the system configuration and reduces the footprint, power consumption and cost. Besides, through a special current injection scheme for the two-segment semiconductor laser, whole wavelength tuning with fixed wavelength spacing can also be realized. It provides a convenient and low-cost photonic solution for flexible and tunable microwave sources.

Distributed generation (DG) is becoming increasingly important due to the serious environmental pollution caused by conventional fossil-energy-based generation and the depletion of non-renewable energy. As the flexible resources in the active distribution network (ADN), battery energy system (BES) and responsive load (RL) are all able to assist renewable DG integration in day-ahead dispatch. In addition, the security and economic level can be significantly improved by adjusting network topology. Therefore, in this paper, a coordinated day-ahead scheduling method incorporating topology reconfiguration, BES optimization and load response is presented to minimize the total day-ahead operational costs in the ADN. Linearized current injection models are presented for renewable DG, RL and BES based on the linear power flow model, and an extensible linear switching operations calculation (ELSOC) method is proposed to address the network reconfiguration. Thus, a mixed integer linear programming (MILP) model is proposed for optimal coordinated operation of an ADN. The correctness and effectiveness of the proposed method are demonstrated by simulations on a modified test system. In addition, the combined scenario and Monte-Carlo method is used to handle the uncertainties of loads and DGs, and the results of different uncertainties can further verify the feasibility of the proposed model.

Electrical Impedance Tomography (EIT) nearly has all the parameters of the ideal of a modality tomography. There is one parameter that makes the EIT modality not yet ideal. It is the low spatial resolution of the image. Unfortunately, it is limited in the range of 5 percent to 10 percent of the object diameter. The causal factor is the limited number of measurement data obtained. The focus of research on EIT at now is the development of functional applications. The novel application developed in this research is to detect bone fractures, mainly due to sports injuries. The hardware characteristics are certainly different from other applications. Optimization of the injection current to match the most resistive characteristics of bone compared to all human body tissues has been carried out. The image of bone is reconstructed using the adjacent method of data collection and the Newton-Raphson iterative algorithm with Tikhonov regularization. The optimization results are seen from the high quality and contrast of the reconstructed image for various injection current values. The current injection frequency is selected at 10 kHz. In the results of this research, the injection current that can produce the highest quality and contrast is 0.3 mA.

In this article, the setup and calibration process of the BCI test according to ISO 11452-4 and a general evaluation and calculation of the total measurement uncertainty is presented. This sample measurement uncertainty calculations can be used as the measurement uncertainty calculations, which are absent in ISO 11452 standards. After the introduction into the measurement uncertainty calculation, the calibration process is critically examined on many sources of measurement uncertainties and mismatches inside the setup, which have significant impact on the calibration and also on the testing process. Additionally, new sources of uncertainty are evaluated in this paper, which can have a high impact on the calibration and testing process. This sample measurement uncertainty calculations can be used as the measurement uncertainty calculations, which are absent in ISO 11452 standards. With all detected sources of uncertainties, the measurement uncertainty calculation models can be used for other international standards with similar calibration and test processes, which are used for testing devices for different fields of application, and by calibration and testing laboratories, to improve the reproducibility of the calibration and testing process.

Dual-wavelength multiple quantum wells (MQWs) have great potential in realizing high quality illumination, monolithic micro light-emitting diode (LED) displays and other related fields. Here, we demonstrate a single chip white light indium gallium nitride (InGaN) LED via the manipulation of the dual-wavelength MQWs. The MQWs contain four pairs of blue light-emitting MQWs and one pair of green light-emitting QW. The fabricated LED chips with nickel/gold (Ni/Au) as the current spreading layer emit white light with the injection current changing from 0.5 mA to 80 mA. The chromaticity coordinates of (0.3152, 0.329) closing to the white light location in the Commission International de I’Eclairage (CIE) 1931 chromaticity diagram are obtained under a 1 mA current injection with a color rendering index (CRI) Ra of 60 and correlated color temperature (CCT) of 6246 K. This strategy provides a promising route to realize high quality white light in a single chip, which will significantly simplify the production process of incumbent white light LEDs and promote the progress of high-quality illumination.

Optimal power flow (OPF) solutions with generalized interline power flow controller (GIPFC) devices play an imperative role in enhancing the power system’s performance. This paper used a novel ant lion optimization (ALO) algorithm which is amalgamated with Lévy flight operator, and an effectual algorithm is proposed named as, ameliorated ant lion optimization (AALO) algorithm. It is being implemented to solve single objective OPF problem with the latest flexible alternating current transmission system (FACTS) controller named as GIPFC. GIPFC can control a couple of transmission lines concurrently and it also helps to control the sending end voltage. In this paper, current injection modeling of GIPFC is being incorporated in conventional Newton-Raphson (NR) load flow to improve voltage of the buses and focuses on minimizing the considered objectives such as generation fuel cost, emissions, and total power losses by fulfilling equality, in-equality. For optimal allocation of GIPFC, a novel Lehmann-Symanzik-Zimmermann (LSZ) approach is considered. The proposed algorithm is validated on single benchmark test functions such as Sphere, Rastrigin function then the proposed algorithm with GIPFC has been testified on standard IEEE-30 bus system.

Power loss management is one of the most significant challenges for reliability improvement of modular multilevel converters (MMCs). In the MMC, the bottom switch/diode in each submodule (SM) normally takes the maximum power loss. In this paper, a power loss optimization control (PLOC) for MMCs is proposed, where the maximum power losses in the bottom switch/diode of each SM can be effectively reduced through injecting optimum second-order harmonic current into the circulating current of MMCs, and accordingly the reliability of MMCs can be improved by the proposed PLOC. Simulation results with PSCAD software and experimental results with a 1 kW MMC platform are provided to confirm the validity of the proposed PLOC for MMCs.

This paper applies the emerging hybrid active third-harmonic current injection converter (H3C) to the battery energy storage system (BESS), forming a novel H3C-BESS structure. Compared with the commonly used two-stage VSC-BESS, the proposed H3C-BESS has the capability to reduce the passive components and switching losses. The operation principle of the H3C-BESS is analyzed and the mathematical model is derived. The closed-loop control strategy and controller design are proposed for different operation modes of the system, which include the battery current/voltage control and the injected harmonic current control. In particular, active damping control is realized through the grid current control, which could suppress the LC-filter resonance without the need of passive damping resistors. Simulation results show that the proposed topology and its control strategy have fast dynamic response, with a setup time of less than 4 ms. In addition, the total harmonic distortions of battery current and grid currents are only 2.54% and 3.15%, respectively. The amplitude of the injected harmonic current is only half of the grid current, indicating that the current injection circuit generates low losses. Experimental results are also provided to verify the validity of the proposed solution.

To light emitting diodes (LEDs), solving the common non-uniform current injection and efficiency degradation issues in (0001) plane micro-LED is essential. Herein, we investigated the light emission characteristics of various mesa sizes and different p-electrode areas toward the realization of coaxial GaInN/GaN multi-quantum-shell (MQS) nanowires (NWs)-based micro-LEDs. As the mesa area was reduced, the current leakage decreases, and further reduction of the area showed a possibility of realizing micro-LED with less current leakage. The large leakage path is mainly associated with the defective MQS structure on the (0001) plane area of each NW. Therefore, more NWs involved in an LED chip will induce higher reverse leakage. The current density-light output density characteristics showed considerably increased electroluminescence (EL) intensity as the mesa area decreased, owing to the promoted current injection into the efficient NW sidewalls under high current density. The samples with a mesa area of 50 × 50 µm showed 1.68 times higher light output density than an area of 100 × 100 µm under a current density of 1000 A/cm . In particular, the emission from (1-101) and (10-10) planes did not exhibit an apparent peak shift caused by the quantum-confined Stark effect. Furthermore, by enlarging the p-electrode area, current can be uniformly injected into the entire chip with a trade-off of effective injection to the sidewall of each NW. High performance of the MQS NW-based micro-LED can be expected because of the mitigated efficiency degradation with a reducing mesa area and an optimal dimension of p-electrode.