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This paper aims to present the design of a novel triangular-shaped wideband microstrip bandpass filter implemented on a low-cost substrate with a notched band for interference rejection.

The conventional dual-stub filter is embedded with simple fractal-based triangular-circular geometries through various iterations to reject wireless local area network (WLAN) signals with a notched band at 5.8 GHz.

The filter covers a wide frequency band from 3.1 to 8.8 GHz and has a fractional bandwidth of 98 per cent with the lower passband of 57.5 per cent and upper passband of 31.6 per cent separated by a notched band at 5.8 GHz. The proposed wideband prototype bandpass filter is fabricated in FR-4 substrate using PCB technology and the simulation results are validated with measurement results which include insertion loss, return loss and group delay. The fabricated filter has a sharp rejection of 28.3 dB at 5.8 GHz. Measured results show good agreement with simulated responses. The performance of the fractal-based wideband filter is compared with other wideband bandpass filters.

In the proposed work, a fractal-based wideband bandpass filter with a notched band is reported. The conventional dual-stub filter is deployed with triangular-circular geometry to design a wideband filter with a notched band to suppress interference signals at WLAN frequency. The proposed wideband filter exhibits smaller size and better interference rejection compared to other wideband bandpass filter designs implemented on low-cost substrate reported in the literature. The aforementioned wideband filter finds application in wideband wireless communication systems.

The purpose of this paper is to derive a new fractal active low-pass filter (LPF) within the local fractional derivative (LFD) calculus on the Cantor set (CS).

To the best of the author’s knowledge, a new fractal active LPF within the LFD on the CS is proposed for the first time in this work. By defining the nondifferentiable (ND) lumped elements on the fractal set, the author successfully extracted its ND transfer function by applying the local fractional Laplace transform. The properties of the ND transfer function on the CS are elaborated in detail.

The comparative results between the fractal active LPF (for γ = ln2/ln3) and the classic one (for γ = 1) on the amplitude–frequency and phase–frequency characteristics show that the proposed method is correct and effective, and is expected to shed light on the theory study of the fractal electrical systems.

To the best of the author’s knowledge, the fractal active LPF within the LFD calculus on the CS is proposed for the first time in this study. The proposed method can be used to study the other problems in the fractal electrical systems, and is expected to shed a light on the theory study of the fractal electrical systems.

This paper aims to design a dual mode X-band substrate integrated waveguide (SIW) bandpass filter in the conventional SIW structure. A pair of back-to-back square and split ring resonator is introduced in the single-layer SIW bandpass filter. The various coupling configurations of SIW bandpass filter using split square ring slot resonator is designed to obtain dual resonant mode in the passband. It is shown that the measured results agree with the simulated results to meet compact size, lower the transmission coefficient, better reflection coefficient, sharp sideband rejection and minimal group delay.

A spurious suppression of wideband response is suppressed using an open stub in the transmission line. The width and length of the stub are tuned to suppress the wideband spurs in the stopband. The measured 3 dB bandwidth is from 8.76 to 14.24 GHz with a fractional bandwidth of 48.04% at a center frequency of 11.63 GHz, 12.59 GHz. The structure is analyzed using the equivalent circuit model, and the simulated analysis is based on an advanced design system software.

This paper discusses the characteristics of resonator below the waveguide cut-off frequency with their working principles and applications. Considering the difficulties in combining the resonators with a metallic waveguide, a new guided wave structure – the SIW is designed, which is synthesized on a planar substrate with linear periodic arrays of metallized via based on the printed circuit board.

This study has investigated the wave propagation problem of the SIW loaded by square ring slot-loaded resonator. The electric dipole nature of the resonator has been used to achieve a forward passband in a waveguide environment. The proposed filters have numerous advantages such as high-quality factor, low insertion loss, easy to integrate with the other planar circuits and, most importantly, compact size.

The fractal and fractional calculus have obtained considerable attention in the electrical and electronic engineering since they can model many complex phenomena that the traditional integer-order calculus cannot. The purpose of this paper is to develop a new fractional pulse narrowing nonlinear transmission lines model within the local fractional calculus for the first time and derive a novel method, namely, the direct mapping method, to seek for the nondifferentiable (ND) exact solutions.

By defining some special functions via the Mittag–Leffler function on the Cantor sets, a novel approach, namely, the direct mapping method is derived via constructing a group of the nonlinear local fractional ordinary differential equations. With the aid of the direct mapping method, four groups of the ND exact solutions are obtained in just one step. The dynamic behaviors of the ND exact solutions on the Cantor sets are also described through the 3D graphical illustration.

It is found that the proposed method is simple but effective and can construct four sets of the ND exact solutions in just one step. In addition, one of the ND exact solutions becomes the exact solution of the classic pulse narrowing nonlinear transmission lines model for the special case 9 = 1, which strongly proves the correctness and effectiveness of the method. The ideas in the paper can be used to study the other fractal partial differential equations (PDEs) within the local fractional derivative (LFD) arising in electrical and electronic engineering.

The fractional pulse narrowing nonlinear transmission lines model within the LFD is proposed for the first time in this paper. The proposed method in the work can be used to study the other fractal PDEs arising in electrical and electronic engineering. The findings in this work are expected to shed a light on the study of the fractal PDEs arising in electrical and electronic engineering.

The purpose of this paper is to propose a set of techniques, in the domain of texture analysis, dedicated to the classification of industrial textures. One of the main purposes was to deal with a high diversity of textures, including structural and highly random patterns.

The global system includes a texture segmentation phase and a classification phase. The approach for image texture segmentation is based on features extracted from wavelets transform, fuzzy spectrum and interaction maps. The classification architecture uses a fuzzy grammar inference system.

The classifier uses the aggregation of features from the several segmentation techniques, resulting in high flexibility concerning the diversity of industrial textures. The resulted system allows on‐line learning of new textures. This approach avoids the need for a global re‐learning of the all textures each time a new texture is presented to the system.

These achievements demonstrate the practical value of the system, as it can be applied to different industrial sectors for quality control operations.

The global approach was integrated in a cork vision system, leading to an industrial prototype that has already been tested. Similarly, it was tested in a textile machine, for a specific fabric inspection, and gave results that corroborate the diversity of possible applications. The segmentation procedure reveals good performance that is indicated by high classification rates, revealing good perspectives for full industrialization.

This paper aims to construct a spatio-temporal emotional framework (STEF) for digital humanities from a quantitative perspective, applying knowledge extraction and mining technology to promote innovation of humanities research paradigm and method.

The proposed STEF uses methods of information extraction, sentiment analysis and geographic information system to achieve knowledge extraction and mining. STEF integrates time, space and emotional elements to visualize the spatial and temporal evolution of emotions, which thus enriches the analytical paradigm in digital humanities.

The case study shows that STEF can effectively extract knowledge from unstructured texts in the field of Chinese Qing Dynasty novels. First, STEF introduces the knowledge extraction tools – MARKUS and DocuSky – to profile character entities and perform plots extraction. Second, STEF extracts the characters' emotional evolutionary trajectory from the temporal and spatial perspective. Finally, the study draws a spatio-temporal emotional path figure of the leading characters and integrates the corresponding plots to analyze the causes of emotion fluctuations.

The STEF is constructed based on the “spatio-temporal narrative theory” and “emotional narrative theory”. It is the first framework to integrate elements of time, space and emotion to analyze the emotional evolution trajectories of characters in novels. The execuability and operability of the framework is also verified with a case novel to suggest a new path for quantitative analysis of other novels.

The purpose of this study is to develop a high-quality factor fractal inductor for wireless applications such as satellite, WLAN, Bluetooth, microwave, radar and cellular phone.

The Hilbert fractal curve is used in the implementation of the proposed inductor. In the proposed inductor, the metal width has split into multiple paths based on the skin depth of the metal. The simulations of the proposed inductor are performed in 180 nm CMOS technology using the Advanced Design System EM simulator.

The multipath technique reduces the skin effects and proximity effects, which, in turn, decreases the series resistance of the inductor and attains high-quality factor over conventional fractal inductor for the equal on-chip area.

The width of the path has chosen higher than the skin depth of the metal for a required operating frequency. Due to cost constraints, the manufacturing of the proposed fractal inductor is limited to a single layer.

The proposed inductor will be useful for the implementation of critical building blocks of radio frequency integrated circuits and monolithic microwave integrated circuits such as low-noise amplifiers, voltage-controlled oscillators, mixers, filters and power amplifiers.

This paper presents for the first time the use of a multipath technique for the fractal inductors to enhance the quality factor.

The purpose of this study is to originally present noise analysis of electrical circuits defined on fractal set.

The fractal integrodifferential equations of resistor-inductor, resistor-capacitor, inductor-capacitor and resistor-inductor-capacitor circuits subjected to zero mean additive white Gaussian noise defined on fractal set have been formulated. The fractal time component has also been considered. The closed form expressions for crucial stochastic parameters of circuit responses have been derived from these equations. Numerical simulations of power spectral densities based on the derived autocorrelation functions have been performed. A comparison with those without fractal time component has been made.

We have found that the Hausdorff dimension of the middle b Cantor set strongly affects the power spectral densities; thus, the average powers of noise induced circuit responses and the inclusion of fractal time component causes significantly different analysis results besides the physical measurability of electrical quantities.

For the first time, the noise analysis of electrical circuit on fractal set has been performed. This is also the very first time that the fractal time component has been included in the fractal calculus-based circuit analysis.

The purpose of this paper is to present the analyses of electrical circuits with arbitrary source terms defined on middle b cantor set by means of nonlocal fractal calculus and to evaluate the appropriateness of such unconventional calculus.

The nonlocal fractal integro-differential equations describing RL, RC, LC and RLC circuits with arbitrary source terms defined on middle b cantor set have been formulated and solved by means of fractal Laplace transformation. Numerical simulations based on the derived solutions have been performed where an LC circuit has been studied by means of Lagrangian and Hamiltonian formalisms. The nonlocal fractal calculus-based Lagrangian and Hamiltonian equations have been derived and the local fractal calculus-based ones have been revisited.

The author has found that the LC circuit defined on a middle b cantor set become a physically unsound system due to the unreasonable associated Hamiltonian unless the local fractal calculus has been applied instead.

For the first time, the nonlocal fractal calculus-based analyses of electrical circuits with arbitrary source terms have been performed where those circuits with order higher than 1 have also been analyzed. For the first time, the nonlocal fractal calculus-based Lagrangian and Hamiltonian equations have been proposed. The revised contradiction free local fractal calculus-based Lagrangian and Hamiltonian equations have been presented. A comparison of local and nonlocal fractal calculus in terms of Lagrangian and Hamiltonian formalisms have been made where a drawback of the nonlocal one has been pointed out.

The purpose of this paper is to present the design of a compact microstrip bandpass filter (BPF) in dual-mode configuration loaded with cross-loop and square ring slots on a square patch resonator for C-band applications.

In the proposed design, the dual-mode response for the filter is realized with two transmission zeros (TZs) by the insertion of a perturbation element at the diagonal corner of the square patch resonator with orthogonal feed lines. Such TZs at the edges of the passband result in better selectivity for the proposed BPF. Moreover, the cross-loop and square ring slots are etched on a square patch resonator to obtain a miniaturized BPF.

The proposed dual-mode microstrip filter fabricated in RT/duroid 6010 substrate using PCB technology has a measured minimum insertion loss of 1.8 dB and return loss better than 24.5 dB with a fractional bandwidth (FBW) of 6.9%. A compact size of 7.35 × 7.35 mm² is achieved for the slotted patch resonator-based dual-mode BPF at the center frequency of 4.76 GHz. As compared with the conventional square patch resonator, a size reduction of 61% is achieved with the proposed slotted design. The feasibility of the filter design is confirmed by the good agreement between the measured and simulated responses. The performance of the proposed filter structure is compared with other dual-mode filter works.

In the proposed work, a compact dual-mode BPF is reported with slotted structures. The conventional square patch resonator is deployed with cross-loop and square ring slots to design a dual-mode filter with a square perturbation element at its diagonal corner. The proposed filter exhibits compact size and favorable performance compared to other dual-mode filter works reported in literature. The aforementioned design of the dual-mode BPF at 4.76 GHz is suitable for applications in the lower part of the C-band.