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Multimodal emotion classification (MEC) involves analyzing and identifying human emotions by integrating data from multiple sources, such as audio, video, and text. This approach leverages the complementary strengths of each modality to enhance the accuracy and robustness of emotion recognition systems. However, one significant challenge is effectively integrating these diverse data sources, each with unique characteristics and levels of noise. Additionally, the scarcity of large, annotated multimodal datasets in Bangla limits the training and evaluation of models. In this work, we unveiled a pioneering multimodal Bangla dataset, MAViT-Bangla (Multimodal Audio Video Text Bangla dataset). This dataset, comprising 1002 samples across audio, video, and text modalities, is a unique resource for emotion recognition studies in the Bangla language. It features emotional categories such as anger, fear, joy, and sadness, providing a comprehensive platform for research. Additionally, we developed a framework for audio, video and textual emotion recognition (i.e., AVaTER) that employs a cross-modal attention mechanism among unimodal features. This mechanism fosters the interaction and fusion of features from different modalities, enhancing the model's ability to capture nuanced emotional cues. The effectiveness of this approach was demonstrated by achieving an F1-score of 0.64, a significant improvement over unimodal methods. [ABSTRACT FROM AUTHOR]

Summary: This study presents a novel method for reducing return loss and achieving lower side lobe levels in small planar antenna arrays (PAAs). Quantum particle swarm optimisation (QPSO) findings are utilised for antenna design modelling and performance assessment utilising the MATLAB‐based moment's code approach and MATLAB‐HFSS interface. The mutual coupling between antenna components is considered and computed using the method of moments (MoM). Changing the array elements' length and spacing will accomplish the abovementioned objectives. The Matlab‐based moments code calculates the antenna components' length and spacing, and the antennas' length and spacing are used to produce the radiation pattern via the Matlab‐HFSS interface. Four examples of small PAA designs are given to illustrate how well the applied methodology works. The method discussed in this paper is generic and can be employed in the future for different sizes of the array elements and the different antenna array structure designs. [ABSTRACT FROM AUTHOR]

We present a method to probe rare molecular dynamics trajectories directly using reinforcement learning. We consider trajectories that are conditioned to transition between regions of configuration space in finite time, such as those relevant in the study of reactive events, and trajectories exhibiting rare fluctuations of time-integrated quantities in the long time limit, such as those relevant in the calculation of large deviation functions. In both cases, reinforcement learning techniques are used to optimize an added force that minimizes the Kullback–Leibler divergence between the conditioned trajectory ensemble and a driven one. Under the optimized added force, the system evolves the rare fluctuation as a typical one, affording a variational estimate of its likelihood in the original trajectory ensemble. Low variance gradients employing value functions are proposed to increase the convergence of the optimal force. The method we develop employing these gradients leads to efficient and accurate estimates of both the optimal force and the likelihood of the rare event for a variety of model systems. [ABSTRACT FROM AUTHOR]

Summary: This research illustrates a precise linear and elliptical antenna array design for synthesising the optimal far‐field radiation pattern in the fifth‐generation (5G) communication spectrum using a meta‐heuristic optimisation technique known as black widow optimisation (BWO). 5G communication is an emerging technology with revolutionary changes in the wireless communication system with ultra‐high data rate, enhanced capacity, low latency and good quality of service. An accurate antenna array design for an ideal far‐field radiation pattern synthesis with a suppressed side lobe level (SLL) value and half power beam width (HPBW) is the most crucial aspect of 5G communications. A suppressed SLL is necessary to reduce interference in the entire side lobe region, whereas a low HPBW is required for long‐distance communication. Here, the BWO is employed to find the optimal feeding current to each array element to lower the SLL and the HPBW value. The BWO algorithm sustains impeccable equity between the exploration and exploitation stages to impact different potential regions of the search space and generate new solutions to attain the global optima by evading the trap of local optima. The design examples of the linear antenna array (LAA) and elliptical antenna array (EAA) are illustrated in this article by applying the optimal feeding currents to each array element. Compared to the uniform antenna array and methodologies described in the recently published literature, the results obtained utilising the BWO algorithm for designing the LAAs and EAAs demonstrate a substantial development in the reduction of SLL and HPBW. [ABSTRACT FROM AUTHOR]

We use a nonequilibrium variational principle to optimize the steady-state, shearinduced interconversion of self-assembled nanoclusters of DNA-coated colloids. Employing this principle within a stochastic optimization algorithm allows us to identify design strategies for functional materials. We find that far-from-equilibrium shear flow can significantly enhance the flux between specific colloidal states by decoupling trade-offs between stability and reactivity required by systems in equilibrium. For isolated nanoclusters, we find nonequilibrium strategies for amplifying transition rates by coupling a given reaction coordinate to the background shear flow. We also find that shear flow can be made to selectively break detailed balance and maximize probability currents by coupling orientational degrees of freedom to conformational transitions. For a microphase consisting of many nanoclusters, we study the flux of colloids hopping between clusters. We find that a shear flow can amplify the flux without a proportional compromise on the microphase structure. This approach provides a general means of uncovering design principles for nanoscale, autonomous, functional materials driven far from equilibrium. [ABSTRACT FROM AUTHOR]

Using large deviation theory and principles of stochastic optimal control, we show that rare molecular dynamics trajectories conditioned on assembling a specific target structure encode a set of interactions and external forces that lead to enhanced stability of that structure. Such a relationship can be formulated into a variational principle, for which we have developed an associated optimization algorithm and have used it to determine optimal forces for targeted self-assembly within nonequilibrium steady-states. We illustrate this perspective on inverse design in a model of colloidal cluster assembly within linear shear flow. We find that colloidal clusters can be assembled with high yield using specific short-range interactions of tunable complexity. Shear decreases the yields of rigid clusters, while small values of shear increase the yields of nonrigid clusters. The enhancement or suppression of the yield due to shear is rationalized with a generalized linear response theory. By studying 21 unique clusters made of six, seven, or eight particles, we uncover basic design principles for targeted assembly out of equilibrium. [ABSTRACT FROM AUTHOR]

We introduce a variational algorithm to estimate the likelihood of a rare event within a nonequilibrium molecular dynamics simulation through the evaluation of an optimal control force. Optimization of a control force within a chosen basis is made possible by explicit forms for the gradients of a cost function in terms of the susceptibility of driven trajectories to changes in variational parameters. We consider probabilities of time-integrated dynamical observables as characterized by their large deviation functions and find that in many cases, the variational estimate is quantitatively accurate. Additionally, we provide expressions to exactly correct the variational estimate that can be evaluated directly. We benchmark this algorithm against the numerically exact solution of a model of a driven particle in a periodic potential, where the control force can be represented with a complete basis. We then demonstrate the utility of the algorithm in a model of repulsive particles on a line, which undergo a dynamical phase transition, resulting in singular changes to the form of the optimal control force. In both systems, we find fast convergence and are able to evaluate large deviation functions with significant increases in statistical efficiency over alternative Monte Carlo approaches. [ABSTRACT FROM AUTHOR]

This paper presents an efficient method to improve the far-field radiation pattern of concentric circular antenna array (CCAA) design using two stochastic optimization algorithms known as social spider algorithm (SSA) and modified social spider algorithm (MSSA). Low side lobe level (SLL) plays a crucial role in reducing the interference with the other frequency components along the entire side lobes of the far-field radiation pattern. SSA and MSAA are the state-of-the-art evolutionary optimization techniques which are applied here to determine the optimal current amplitude and the inter-element distance between two consecutive antennae of the 3-ring CCAA. In this paper, the optimal results achieved by using SSA, MSSA for (4, 6, 8) elements and (8, 10, 12) elements 3-ring CCAAs, with and without centre elements are reported. The results achieved by employing SSA and MSSA show a considerable improvement in SLL reduction as compared to the uniform and the other array patterns reported in the state-of-the-art literature. [ABSTRACT FROM AUTHOR]

Combining photonic excitation and acoustic detection, photoacoustic imaging (PAI) presents one of the most promising noninvasive biomedical diagnostic modalities, but this technique still lacks efficient nano-sized contrast agents absorbing light in the region of relative tissue transparency (630–900 nm). Here, we explore the use of titanium nitride (TiN) nanoparticles (NPs) fabricated by methods of pulsed laser ablation in liquids as a contrast agent in PAI. When prepared in acetone, the NPs are spherical, have an average size of 25 nm, and exhibit a broad plasmonic absorption peak around 700 nm. We show that solutions of these NPs render possible a strong nonlinear photoacoustic response and the generation of photoacoustic images with 67 μm resolution within the biological transparency window. The observed effect is explained by a plasmonically enhanced two-photon absorption process in TiN NPs. Combined with earlier demonstrated capability of generating photothermal therapeutic effect, relative chemical purity, and excellent biocompatibility, laser-synthesized TiN NPs promise attractive applications in biomedical theranostics involving imaging modalities based on photoacoustics microscopy or tomography. [ABSTRACT FROM AUTHOR]

This article presents a precise approach for far‐field radiation pattern (FFRP) correction of mutually coupled discrete dipole element (DDE) array of monopole antennas and concentric circular antenna array (CCAA) of dipole elements by employing the parametric assimilation technique (PAT). The effect of mutual coupling is a crucial part of any practical antenna array design issue. Various techniques have been suggested to calculate, compensate and reduce the mutual coupling effect during the last few decades. This article shows an exact method for mutual coupling inclusive corrected radiation pattern synthesis using PAT. The parameters of mutual impedance are calculated and assimilated with the values of the desired radiation pattern. The employed technique is cost‐effective, less complex and easy to implement while achieving better performance for mutually coupled DDE array and CCAA synthesis. Grey wolf optimisation (GWO) is a state‐of‐the‐art stochastic algorithm applied here to find the optimal values of the current amplitude excitation weights and the inter‐element spacing between each element of the array in the DDE array and three‐rings structure CCAA for the desired, uncorrected and corrected FFRP synthesis. Some well‐established evolutionary optimisation techniques like particle swarm optimisation (PSO), differential evolution (DE) and social spider algorithm (SSA) are also employed in this article for the sake of comparison with the results achieved by using the GWO algorithm. Finally, the supremacy of GWO algorithm based design is demonstrated and validated by employing the 16‐elements DDE array of monopole antennas and the three‐ring CCAA of dipole elements. [ABSTRACT FROM AUTHOR]

Transition metal‐catalyzed enantioselective functionalization of ubiquitous C−H bonds has proven to be promising field as it offers the construction of chiral molecular complexity in a step‐ and atom‐economical manner. In recent years, gold has emerged as an attractive contender for catalyzing such reactions. The unique reactivities and selectivities offered by gold catalysts have been exploited to access numerous asymmetric transformations based on gold‐catalyzed C−H functionalization processes. Herein, this review critically highlights the major advances and discoveries made in the enantioselective C−H functionalization under gold catalysis which is accompanied by mechanistic insights at appropriate places. [ABSTRACT FROM AUTHOR]

Gummy smile is a quite frequently found esthetic alteration characterized by excessive display of gingiva during smiling. Several causes have been implicated in the literature, but a dearth of clinical decision-making process has been found in the surgical treatment of excessive gingival display. An external bevel gingivectomy with osseous correction was performed in anterior maxillary region in accordance with the proposed decision-making process. The clinical observation at 1 month postoperatively revealed restoration of natural smile with 1-2 mm of facial gingival display. The outcome seems to suggest that this proposed decision-making process can provide valid treatment options for gummy smile cases. [ABSTRACT FROM AUTHOR]

Gold complexes have emerged as the catalysts of choice for various functionalization reactions of C–C multiple bonds due to their inherent carbophilic nature. In a parallel space, efforts to realize less accessible cross-coupling reactivity have led to the development of various strategies that facilitate the arduous Au(I)/Au(III) redox cycle. The interplay of the two important reactivity modes encountered in gold catalysis, namely carbophilic activation and Au(I)/Au(III) catalysis, has allowed the development of a novel mechanistic paradigm that sponsors 1,2-difunctionalization reactions of various C–C multiple bonds. Interestingly, the reactivity as well as selectivity obtained through this interplay could be complementary to that obtained by the use of various other transition metals that mainly involved the classical oxidative addition/migratory insertion pathways. The present review shall comprehensively cover all the 1,2-difunctionalization reactions of C–C multiple bonds that have been realized by the interplay of the two important reactivity modes and categorized on the basis of the method that has been employed to foster the Au(I)/Au(III) redox cycle. [ABSTRACT FROM AUTHOR]

In this paper, an optimal far-field radiation pattern synthesis by using time modulation technique is carried out for a compact circular antenna array (CAA) design using a stochastic optimization method called krill herd (KH) optimization. A compact antenna array is achieved by reducing the inter-element spacing between the array elements, which leads to the miniaturization of the size of the array. On the other hand, an improved far-field radiation characteristic is achieved with a low side lobe level (SLL) and narrow first null beam width (FNBW). A low SLL is an essential requirement to reduce the interference with the other systems operating in the same frequency band. A narrow FNBW is necessary to obtain a high directivity. In time modulation technique, 'time' has the most significant role. It is considered the fourth-dimensional parameter, which plays the role of an additional degree of freedom to achieve an improved radiation pattern. The time-modulated antenna array (TMAA) radiates at various harmonic frequencies for the periodic switching time sequence. In this paper, the generation of the radiation pattern at the fundamental/central frequency only is considered. The KH algorithm is a flexible and robust search algorithm. It is applied here to find out the optimum sets of switching on-time duration for each array element and to determine the optimum inter-element separation between two array elements of the 20- and 36-element time-modulated circular antenna array (TMCAA). Particle swarm optimization (PSO) and differential evolution (DE) optimization techniques are also individually applied for the same design purpose to prove the superiority of the KH algorithm–based design. Finally, statistical analysis is performed to ensure the significance of the numerical results. [ABSTRACT FROM AUTHOR]

An efficient compensation method is proposed for the reduction of mutual coupling among the elements of an antenna array using the optimum current amplitude excitation weights. The performance of an antenna array degrades heavily due to mutual coupling. The mutual coupling effect can neither be eliminated nor be ignored in the context of the antenna array design. Several analytical and numerical techniques have been proposed in the past few decades for the calculation and compensation of mutual coupling effect. Here, the mutual coupling is compensated by reducing the driving impedance of each identical array element in the array by adopting grey wolf optimization and moth flame optimization algorithms, respectively. The sum of the driving impedances of each element of the antenna array is reduced efficiently by adjusting the feed current amplitudes of all the individual array elements. Compared to the existing known methods, the proposed method is less complex, cost‐effective and easy to implement for commercial and industrial applications to achieve better performance. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to demonstrate the presence of dental caries through a photoacoustic imaging system with visible and near-infrared wavelengths, highlighting the differences between the 2 spectral regions. The depth at which carious tissue could be detected was also verified. Materials and Methods: Fifteen permanent molars were selected and classified as being sound or having incipient or advanced caries by visual inspection, radiography, and optical coherence tomography analysis prior to photoacoustic scanning. A photoacoustic imaging system operating with a nanosecond pulsed laser as the light excitation source at either 532 nm or 1064 nm and an acoustic transducer at 5 MHz was developed, characterized, and used. En-face and lateral (depth) photoacoustic signals were detected. Results: The results confirmed the potential of the photoacoustic method to detect caries. At both wavelengths, photoacoustic imaging effectively detected incipient and advanced caries. The reconstructed photoacoustic images confirmed that a higher intensity of the photoacoustic signal could be observed in regions with lesions, while sound surfaces showed much less photoacoustic signal. Photoacoustic signals at depths up to 4 mm at both 532 nm and 1064 nm were measured. Conclusion: The results presented here are promising and corroborate that photoacoustic imaging can be applied as a diagnostic tool in caries research. New studies should focus on developing a clinical model of photoacoustic imaging applications in dentistry, including soft tissues. The use of inexpensive light-emitting diodes together with a miniaturized detector will make photoacoustic imaging systems more flexible, user-friendly, and technologically viable. [ABSTRACT FROM AUTHOR]

This paper presents a time modulated far-field radiation pattern synthesis of a compact circular antenna array (CAA) by employing a stochastic optimization technique known as grey wolf optimization (GWO). The compactness of the antenna array is achieved by reducing the inter-element distances between the elements of the array which leads to the miniaturization of the antenna array size. On the other hand, an optimal far-field radiation characteristic is achieved by suppressing the side lobe level (SLL) as well as by narrowing the first null beamwidth (FNBW). A lower SLL value is necessary to avoid the interference with the system working in the same frequency, whereas, a narrow FNBW helps the antenna array to attain a high directivity. The performance of a time modulated antenna array (TMAA) depends on the rise on–off time, pulse shape as well as on the switching time duration of each element of the array which radiates at different harmonic frequencies. In this paper, the generation of radiation pattern at the fundamental/central frequency and its first two harmonic frequencies are considered for the design issue. [ABSTRACT FROM AUTHOR]

This paper presents an efficient approach for the design of a non-uniform single ring circular antenna array (CAA) for the synthesis of the optimal far-field radiation pattern. A recently proposed meta-heuristic-based optimization technique known as ant lion optimization (ALO) is applied in this paper to determine the optimum set of current amplitude excitation weights and the inter-element distance among the array elements to reduce the side lobe level (SLL) and 3-dB beam width considering the mutual coupling effect. The results achieved by employing the ALO algorithm are compared with the uniform radiation pattern and with those of the recently reported literature containing equal sets of elements to prove the superiority of ALO algorithm. Three different design examples of 8, 10, and 12 elements CAA are presented, and their performances are compared to illustrate the capability of the ALO algorithm-based approach over those of the recently reported literature. [ABSTRACT FROM AUTHOR]

This article shows the design of a non‐uniformly excited single ring circular antenna array (CAA) for the synthesis of optimal far‐field radiation characteristics. A recently proposed meta‐heuristic based optimization algorithm called gray wolf optimization (GWO) and state‐of‐the‐art swarm intelligence based evolutionary optimization technique known as particle swarm optimization with a distribution based update mechanism (PSOd) are individually applied to determine the optimum set of current excitation amplitude weights and the inter‐element spacing among the array elements to reduce the side lobe level and 3‐dB beamwidth considering the mutual coupling. The results obtained by employing PSOd and GWO are compared to those of the uniform radiation pattern and the recently published results of state‐of‐the‐art literature having equal sets of elements to show the superiority of employed approaches. Three different design examples of 8, 10, and 12 elements CAA are reported in this article to study the performances of PSOd and GWO algorithm‐based results over the results of other recently reported literature. [ABSTRACT FROM AUTHOR]

This paper presents an accurate design approach for concentric circular antenna array (CCAA) synthesis to improve the far-field radiation characteristics using a meta-heuristic optimization technique called ant lion optimization (ALO). The far-field radiation pattern is improved with lower side lobe level (SLL) which is essential for the reduction of interference in the entire side lobe regions. The ALO algorithm is a recently proposed evolutionary technique which is applied to determine the optimal sets of current excitation weights and to find the optimal inter-element spacing between the array elements in the 3-ring structure of the CCAA design. In this context, the design examples of two 3-ring CCAAs, one having the set of (4, 6, 8) elements and the other having the set of (8, 10, 12) elements, with and without the centre element, are presented by optimizing the array parameters. The results obtained by using the ALO algorithm–based approach show considerable improvement of SLL with respect to that of the uniform array pattern and those of the methods reported in the recent literature. [ABSTRACT FROM AUTHOR]

Multifunctional BiFeO3 nanostructure anchored TiO2 nanotubes are fabricated by coupling wet chemical and electrochemical routes. BiFeO3/TiO2 nano-heterostructure exhibits white-lightinduced ferroelectricity at room temperature. Studies reveal that the photogenerated electrons trapped at the domain/grain boundaries tune the ferroelectric polarization in BiFeO3 nanostructures. The photon controlled saturation and remnant polarization opens up the possibility to design ferroelectric devices based on BiFeO3. The nano-heterostructure also exhibits substantial photovoltaic effect and rectifying characteristics. Photovoltaic property is found to be correlated with the ferroelectric polarization. Furthermore, the nonvolatile resistive switching in BiFeO3/TiO2 nanoheterostructure has been studied, which demonstrates that the observed resistive switching is most likely caused by the electric-field-induced carrier injection/migration and trapping/detrapping process at the hetero-interfaces. Therefore, BiFeO3/TiO2 nano-heterostructure coupled with logic, photovoltaics and memory characteristics holds promises for long-term technological applications in nanoelectronics devices. [ABSTRACT FROM AUTHOR]

The impedance, capacitance and conductance of deionized waterglucose polar solution is measured by employing impedance spectroscopy and a quasi-oscillatory nature of variation with glucose content in the solution is observed. Such quasi-oscillatory nature is attributed to the randomly distributed water-water, waterglucose and glucose-glucose dipole interactions at the molecular level in the solution. A relevant analytical model is developed on the basis of such random distribution of the molecular dipoles and the experimental data agree well with those obtained from the theoretical model. The electrical parameters are measured in the frequency range of 100Hz to 4MHz for the volume fractions of glucose with respect to water in the range of 0.1 to 0.5. The impedance, capacitance and conductance are obtained to be in the range of 1.03 kΩ - 112 kΩ, 34.9 pF - 1.66 nF, and 8.95 μS - 52.9 μS respectively for the glucose volume fraction range considered. [ABSTRACT FROM AUTHOR]

In this work, n-ZnO-nanowire/p-Si junction diodes have been fabricated and characterized both physically as well as electrically. The measurements are performed on a single standalone nanowire diode for the investigation of electrical transport through the nano-junction. The rectification properties of the single n-ZnO nanowire/p-Si diode have been studied for various input waveforms and frequencies. The diodes exhibit very promising rectification as well as switching behavior with no charge storage effect and consequently, a switching time as small as ~1ms has been achieved. [ABSTRACT FROM AUTHOR]

C-H functionalization, chiral ligands, enantioselective synthesis, gold catalysis, merged gold/organo catalysis These transformations have been achieved by employing 1) the chiral gold complexes, and 2) achiral gold complexes along with chiral amines or chiral Brønsted acids. Keywords: C-H functionalization; chiral ligands; enantioselective synthesis; gold catalysis; merged gold/organo catalysis EN C-H functionalization chiral ligands enantioselective synthesis gold catalysis merged gold/organo catalysis 1 1 1 04/08/22 20220406 NES 220406 B A comprehensive overview b of enantioselective C-H functionalization reactions under gold catalysis is given. [Extracted from the article]

There is already a societal awareness of the growing impact of nanoscience and nanotechnology, with nanomaterials (with at least one dimension less than 100 nm) now incorporated in items as diverse as mobile phones, clothes or dentifrices. In the healthcare area, nanoparticles of biocompatible materials have already been used for cancer treatment or bioimaging enhancement. Nanotechnology in dentistry, or nanodentistry, has already found some developments in dental nanomaterials for caries management, restorative dentistry and orthodontic adhesives. In this review, we present state-of-the-art scientific development in nanodentistry with an emphasis on two imaging techniques exploiting nanomaterials: optical coherence tomography (OCT) and photoacoustic imaging (PAI). Examples will be given using OCT with nanomaterials to enhance the acquired imaging, acting as optical clearing agents for OCT. A novel application of gold nanoparticles and nanorods for imaging enhancement of incipient occlusal caries using OCT will be described. Additionally, we will highlight how the OCT technique can be properly managed to provide imaging with spatial resolution down to 10′s–100′s nm resolution. For PAI, we will describe how new nanoparticles, namely TiN, prepared by femtosecond laser ablation, can be used in nanodentistry and will show photoacoustic microscopy and tomography images for such exogenous agents. [ABSTRACT FROM AUTHOR]

In this paper, an optimal far‐field radiation pattern synthesis by using time modulation technique is carried out for linear antenna array (LAA), and concentric circular antenna array (CCAA) designs using a stochastic optimization method called grey wolf optimization (GWO). An improved far‐field radiation characteristic mainly depends on the synthesis of low side lobe level (SLL) and narrow first null beam width (FNBW). A low SLL is a requirement to reduce the interference by the other systems operating in the same frequency band. A narrow FNBW is necessary to obtain a high directivity. In time modulation technique, "time" has a most significant role. It is considered as the fourth‐dimensional parameter as it plays the role of an additional degree of freedom to achieve an improved radiation pattern. The time‐modulated antenna array (TMAA) radiates at various harmonic frequencies for the periodic switching time sequence. In this paper, the generation of radiation pattern only at the fundamental/central frequency and at its first two harmonic frequencies are considered. The GWO algorithm is a flexible and robust search algorithm and is applied here to find out the optimum sets of switching on‐time duration for each array element and to determine the optimum inter‐element separation between two array elements of the 16‐element time‐modulated linear antenna array (TMLAA) and the nine‐ring time‐modulated concentric circular antenna array (TMCCAA). The GWO algorithm‐based results show a substantial improvement in far‐field radiation pattern synthesis compared with the uniform radiation pattern and those of the methods reported in state‐of‐the‐art literature. [ABSTRACT FROM AUTHOR]

This paper presents an accurate approach to design a symmetrical linear antenna array (LAA) and a non‐uniformly excited single ring circular antenna array (CAA) to improve the far‐field radiation characteristics. The far‐field radiation pattern is improved with lower side lobe level (SLL) which is essential for the reduction of interference in the entire side lobe regions. A recently proposed meta‐heuristic based optimization algorithm called moth flame optimization (MFO) is applied to determine the optimal sets of current excitation weights and the inter‐element spacing among the array elements to reduce the SLL. In this context, 10‐element and 16‐element LAA and 8‐element, 10‐element, and 12‐element CAA design examples are presented by optimizing the array parameters. The simulation results obtained by using MFO algorithm based approach yield a considerable improvement in SLL and some marked improvement of half power beam width with respect to the uniform array pattern and those of the recently reported literature. [ABSTRACT FROM AUTHOR]