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In the active distribution networks (ADNs), the emerging trend of high penetration of sustainable energy sources such as wind turbines, photovoltaics, and the forthcoming integration of energy storage devices and additional dynamic loads like plug‐in‐electric vehicles (PEVs) influences to change the nature of electric distribution networks. Consequently, it deteriorates power quality and reliability in terms of unacceptable voltage rise‐drop, harmonic distortion, voltage unbalance, and excessive power loss. In this context of transition into the active distribution network, the probabilistic optimal power flow (P‐OPF) in the ADN is considered an important tool that helps the distribution grid operators for defining the optimal settings of the system's control variables. However, the optimal solution of P‐OPF becomes highly complex while considering the multiple variables, time‐varying characteristics and operational uncertainties associated with sustainable resources, consumer behaviour and electricity market prices. This review aims at promoting the research and discussion of P‐OPF studies in the context of ADNs characteristics and challenges. First, we perform a data‐driven and visualized scientometric analysis of 1988 quality documents retrieved from the Scopus during the last ten years using VOSviewer software. Second, an in‐depth investigation of the recent and emerging techniques for solving the P‐OPF problem is presented. Third, a set of recommendations and highlights of future challenges for P‐OPF in ADNs are offered. The review findings showed high interest among the scientific community in sustainable energy source integration, given the recent rise in publications and citations. Also, there is still a lack of innovative optimization techniques that can adequately handle the current issues associated with P‐OPF and objectives with fair computational efficiency and accuracy. Finally, this paper offers a guide for P‐OPF researchers to navigate the recent studies considering the sustainable sources, spot the new research frontiers, and identify the most impactful countries and publishers. [ABSTRACT FROM AUTHOR]

A compact filtering Wilkinson power divider with harmonic suppression based on lumped components is presented in this paper. The new divider uses two 5th-order elliptic-function low-pass filters to replace the quarter wavelength microstrip lines of the conventional Wilkinson power divider. The structure combines the power divider and the filter into a complete device. By integrating elliptic low-pass filters with the power divider, the proposed structure can suppress harmonics due to the filter's band-notched characteristic. The power divider demonstrates a measured suppression of 37.1 dB for the second harmonic, 36.6 dB for the third harmonic, 38.6 dB for the fourth harmonic respectively. The harmonic suppression is higher than 20 dB from 2.75 to 7.035 GHz. Furthermore, lumped components are utilized to achieve improvement on size reduction. Compared with the conventional divider, the proposed structure effectively reduces the size by 77 %. The insertion loss is 3.2 dB at the center frequency (1.45GHz). [ABSTRACT FROM AUTHOR]

Discusses an internal friction study of neutron-irradiation effects on an amorphous alloy. Description of the position of internal friction peak after irradiation; Effect of radiation damage on crystalline materials; Information on the temperature dependence of internal friction.

Helical gratings (HGs) have an achievement of flexible mode conversion for fibre‐guided orbital angular momentum (OAM) modes. Sampled reflection HGs can realise the generation and conversion of OAM mode with comb spectra. They can be used to simultaneously filter wavelengths and convert modes, and thus may be applied to the hybrid multiplexing technology with wavelength division multiplexing and mode‐division multiplexing. [ABSTRACT FROM AUTHOR]

A novel miniaturised dual‐band bandpass filter (BPF) using improved split ring λ/4 resonator and stepped impedance resonator (SIR) is proposed. A simple analysis is given for each resonator. By tuning the geometric parameters of the resonators, the two passbands of the BPF can be adjusted separately. Source‐load coupling is adopted to achieve more transmission zeros in the stopband. The new dual‐band BPF, which has a miniature circuit size of 0.18 × 0.18λg, presents narrow and sharp passband characteristics. Good agreement is found between simulated and measured results, which verify the high‐frequency selectivity. [ABSTRACT FROM AUTHOR]

A novel dual‐band Wilkinson power divider (WPD) is designed for the purpose of operating at two arbitrary frequencies. The theory and design procedure of the novel component are presented in detail. For demonstration, a dual‐band WPD with operating frequencies of 1.0 and 2.6 GHz is proposed, fabricated and tested. The good agreement between the measured and simulated results confirmed the design concept. Measurements show that insert losses both at the two central frequencies are less than 3.3 dB. Both return loss and port isolation have good performances, which are more than 21 and 28 dB separately. [ABSTRACT FROM AUTHOR]

A novel compact structure for dual-band Wilkinson power divider has been proposed. The power divider consists of a single line, two coupled lines and four lumped elements. Using even- and odd-mode analysis, the design equations have been obtained through rigorous derivation. The odd-mode impedance Z o is a free variable here, it can be used to control the coupling between the coupled lines, as well as the values of the inductor and capacitor. This provides much flexibility and convenience to our design. Moreover, it significantly widens the frequency ratio to be 10 or even more. [ABSTRACT FROM PUBLISHER]

A multi‐stage least mean square (MLMS) algorithm based on polynomial fitting in time‐varying systems is proposed. As the name implies, the MLMS algorithm is divided into different stages in sequence. In non‐stationary environments, the optimal weight coefficients of the adaptive filter are variable with time and they are assumed to be approximated by a polynomial. According to the conditions above, the convergence of the MLMS algorithm is verified through theoretical analysis and formula derivation. Similar to the least mean square (LMS) algorithm, the step size μ must be chosen in the specific range to guarantee the feasibility and effectiveness of the MLMS algorithm. Compared with the LMS, LMF and NLMS algorithms, the MLMS algorithm provides the best convergence performance in the simulation experiments. [ABSTRACT FROM AUTHOR]

The design of an ultra-compacted silicon-based bandpass filter in the sub-terahertz frequency range is explored. A filter with combline topology consisting of multilayered resonators and a cross-coupling capacitor has been designed in 0.13 µm SiGe. The dimensions of the implemented filter are 40×130 µm2, which are even smaller than a ground-signal-ground probing pad with 100 µm pitch. Meanwhile, the filter achieves a 3 dB bandwidth of about 32.0 GHz (22.0%) and an insertion loss of -7.7 dB at the centre frequency of 143 GHz. [ABSTRACT FROM AUTHOR]