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The relevance of the subject matter is conditioned by the high-efficiency use of reconfigurable manufacturing systems during construction work and the associated need to develop and implement technological machines with replaceable working bodies. The purpose of this study is to analyze the invariance of the equipment used by types of work in landscape and landscape construction. The study used theoretical methods of analysis and synthesis of information on the principles of the practical application of a universal machine with a wide range of mounted technological working bodies. The results obtained indicate the high relevance of the issue of the rapid changeability of mounted technological working bodies. Its effective solution lies in the creation of reconfigurable production machines based on a universal wheelbase with replaceable working bodies of variable layout by type of work, for which a new design of an inter-module basing and fastening device is proposed. The possibility of its practical application in the BobCat loader system is considered. It is established that, in general, the use of the BobTach mounting frame during various technological operations ensures an increase in the efficiency of this technological equipment. In addition, it significantly increases the performance of the entire model range of equipment and testifies to the versatility of the specified mounting frame. The practical significance of the results obtained is conditioned by the possibility of their application in the development and implementation of modern technological machines with rapidly replaceable working bodies in the agricultural sector and road construction. [ABSTRACT FROM AUTHOR]

Incorporating AC-type flying capacitors (FC) between series-connected devices is an effective way to enhance the rated voltage for high-power applications based on current source converters (CSCs). Through appropriate modulation and FC voltage control, it is possible to achieve improved DC bus voltage quality with reduced common-mode voltage (CMV) and low dv/dt. On the other hand, the parallel CSC is a popular choice for increasing the system's rated current to accommodate higher power applications. The use of interleaved modulation techniques can improve the harmonic performance of parallel converters while reducing the need for passive filters. The modular flying capacitor clamped (FCC)-CSC structure can combine these advantages, achieving higher rated power along with improved power quality on both the DC and AC sides. Moreover, the enhanced AC quality contributes to the regulation of FC voltage and further improves the DC-side voltage quality. This paper analyzes the operation principle of the parallel FCC-CSC structure and proposes an interleaved space vector modulation (SVM) method to enhance the harmonic performance of the AC output. Additionally, an optimized zero-state replacement (ZSR) based FC voltage control and a DC-link current balance strategy built on this control are introduced. Simulation and experimental results validate the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

Summary: This study proposes a new design for a non‐isolated buck converter with continuous input current. As required, the integration of additional modules into the existing structure permits a significant decrease in the converter's gain to attain significantly lower values. In order to create the proposed converter, the input voltage connections to the Ćuk converter were changed. In this configuration, the operational state of the Ćuk converter has been changed from buck‐boost to step‐down by connecting the input power source's negative polarity to the inductor's terminal. In addition, the proposed converter benefits from a common ground between the input source and output port. Moreover, it can achieve a significant reduction in gain by increasing the number of series modules. Finally, the compact converter was smoothly incorporated onto a printed circuit board (PCB) and afterward validated by an output power of 80 watts. [ABSTRACT FROM AUTHOR]

The presented paper explores the potential of the MICADO method in modular structures using a parametric development approach. MICADO is an innovative building production system that uses autonomous production lines to fabricate components, which are then assembled on site. By combining frame-supported modulus systems with prefabricated panels for exterior walls, the MICADO approach allows for the simultaneous installation of components. The study examines how MICADO structures perform under earthquake and gravity loads, addressing practical challenges such as column spacing and roof detailing. It specifically looks at parameters that are still unknown due to its new structural type. An L-shaped architectural case study is employed to evaluate structural elements' resistance and assess the lateral stability of buildings under earthquake load. The results of the study suggest that increasing the distance between columns from 300 to 450 mm is a feasible option though the demand strength of elements increased slightly. In the L-shaped plan, there are important elements such as the edge column that significantly affect the structural behavior. Ultimately, the MICADO structure and its components offer a range of design possibilities, including the creation of green spaces on the roof. [ABSTRACT FROM AUTHOR]

Abstract Inferring relations from correlational data allows researchers across the sciences to uncover complex connections between variables for insights into the underlying mechanisms. The researchers often represent inferred relations using Gaussian graphical models, requiring regularization to sparsify the models. Acknowledging that the modular structure of these inferred networks is often studied, we suggest module-based regularization to balance under- and overfitting. Compared with the graphical lasso, a standard approach using the Gaussian log-likelihood for estimating the regularization strength, this approach better recovers and infers modular structure in noisy synthetic and real data. The module-based regularization technique improves the usefulness of Gaussian graphical models in the many applications where they are employed.

In the field of astronomical observation, large space telescopes are key tools for deep space exploration. However, the aperture of space telescopes is limited by the ability to fabricate large monolithic mirrors or lenses and by severe restrictions on the overall volume and mass capacity of the launch vehicle. The use of robots for autonomous assembly while in orbit is a promising option for the deployment of large-aperture space telescopes. In this paper, we describe a modular robotic manipulator that offers high precision and flexibility. A space telescope ground assembly system is then designed, the key components of which are a redundant robotic manipulator and a reconfigurable telescope unit. The ground-based assembly of the space telescope is implemented through a combination of trajectory planning, visual perception, and robotic supple control techniques, validating the ability of the robotic manipulator to automatically assemble modular space telescopes. Finally, the developed robotic manipulator is used to conduct ground assembly demonstration experiments, and the modular space telescope is assembled according to the assembly task plan, accumulating technical experience for future space telescope assembly tasks in orbit. [ABSTRACT FROM AUTHOR]

The integration of sustainability principles into the structural design and decision-making processes for transportation infrastructure, particularly concerning reinforced concrete precast modular frames (RCPMF), is recognized as crucial for ensuring outcomes that are environmentally responsible, economically feasible, and socially beneficial. In this study, this challenge is addressed, with the significance of sustainable development in modern engineering practices being underscored. A novel approach, which is a combination of multi-objective optimization (MOO) with multi-criteria decision-making (MCDM) techniques, is proposed, tailored specifically for the design and selection of RCPMF. The effectiveness of three repair operators—statistical-based, random, and proximity-based—in optimizing economic, environmental, and social objectives is evaluated. Precise evaluation of objective functions is facilitated by a customized Non-dominated Sorting Genetic Algorithm II (NSGA-II) algorithm, complemented by a detailed life cycle analysis (LCA). The utilization of simple additive weighting (SAW) and fair un choix adéquat (FUCA) methods for the scoring and ranking of the MOO solutions has revealed that notable excellence in meeting the RCPMF design requirements is exhibited by the statistical-based repair operator, which offers solutions with lower impacts across all dimensions and demonstrates minimal variability. MCDM techniques produced similar rankings, with slight score variations and a significant correlation of 0.9816, showcasing their consistent evaluation capacity despite distinct operational methodologies. [ABSTRACT FROM AUTHOR]

Due to the properties of high thrust density, power density, and efficiency, Linear Hybrid Excited Flux Switching Machines (LHFSM) are centric for many researchers, especially in rail transit applications. A segmented mover dual stator LHFSM (SMDS-LHFSM) with concentrated armature and field windings is proposed in this paper. The concentrated windings help in reducing the overall copper losses. Flux gaps are added between the mover segments, making the machine a fault-tolerant. A small quantity of permanent magnets is used to reduce the overall cost of the machine. The suitable coil combination and open-circuit flux linkage are derived by magnetic circuit modeling and validated by FEM to reduce time and drive storage. Genetic algorithm (GA) is used to globally optimize the varying parameters of the proposed design and improve the initial performance. After GA, the thrust and thrust ripples are improved by 35.92% and 13.16%, respectively. A mathematical model is developed to verify the fault-tolerant capability and thrust of the proposed machine. Key electromagnetic performance parameters are investigated in depth. The proposed design has 17.6% higher thrust than the conventional machine. Finally, a prototype is fabricated to validate the theoretical analysis. The proposed SMDS-LHFSM has achieved fault-tolerant capability by achieving the mutual inductance value close to zero, flux regulation of 61.16% that is important in variable speed applications and a good temperature distribution after putting it for 2 hours under test.

Incorporating AC-type flying capacitors (FC) between series-connected devices is an effective way to enhance the rated voltage for high-power applications based on current source converters (CSCs). Through appropriate modulation and FC voltage control, it is possible to achieve improved DC bus voltage quality with reduced common-mode voltage (CMV) and low dv/dt. On the other hand, the parallel CSC is a popular choice for increasing the system’s rated current to accommodate higher power applications. The use of interleaved modulation techniques can improve the harmonic performance of parallel converters while reducing the need for passive filters. The modular flying capacitor clamped (FCC)-CSC structure can combine these advantages, achieving higher rated power along with improved power quality on both the DC and AC sides. Moreover, the enhanced AC quality contributes to the regulation of FC voltage and further improves the DC-side voltage quality. This paper analyzes the operation principle of the parallel FCC-CSC structure and proposes an interleaved space vector modulation (SVM) method to enhance the harmonic performance of the AC output. Additionally, an optimized zero-state replacement (ZSR) based FC voltage control and a DC-link current balance strategy built on this control are introduced. Simulation and experimental results validate the effectiveness of the proposed methods.

It has been experimentally established that larger colonies of Dynamena pumila (Hydrozoa, Cnidaria) grown in the laboratory, including 10–11 young shoots, are less resistant to increases in water temperature to the upper temperature limit of this species (25 °C) than the same smaller colonies with one or two shoots. As the temperature rises, some of the hydrants temporarily degrade, and colonies with a large number of shoots experience a greater food shortage, since they have more growth zones that require a continuous influx of cells and food. The state of the colonies was determined by pulsations of the tops of the stolons, which were recorded using time-lapse microvideo photography. Colonies were grown in aquariums with sea water at T = 14 °C. During the first day after the temperature increased from 14 to 25 °C, growth pulsations became more frequent without changing the characteristic sequence of stages of expansion and contraction of the stolon apex. On the second day and further, growth pulsations varied more and more in frequency and amplitude until growth stopped. A rapid decrease in water temperature after five days of thermal shock to 15–16 °C and subsequent maintenance for five days did not lead to the restoration of pulsations in the majority of colonies, although in our previous similar experiment performed on small colonies, restoration was evident already on the third day of maintenance at 15–16 °C and was expressed in the resumption of stolon growth, stabilization of the frequency, amplitude and sequence of phases of growth pulsations. The results of the experiments confirmed that by recording the pulsation indicators of the growth tips of hydroids, it is possible to detect the reaction of the colonial organism to external influences immediately, i.e. within one to two hours after the start of exposure, and this reaction, according to its main characteristics, is constant, without changing over the next few days.

Aiming at the current situation of low endurance and high cost of mobile monitoring equipment for aquaculture, which limits the widespread application of such equipment, a small portable AUV for mobile and fixed-point monitoring of fishery aquaculture is proposed and developed. A seal-like operation mode is proposed, replacing expensive underwater inertial navigation systems with conventional GNSS. The three main hulls are arranged in a pin pattern with a modular structure to increase smoothness. The unpowered diving and floating are controlled by the motor-controlled piston altering the volume of the external oil bladder. With the low-power STM32F407 chip as the control core, FreeRTOS embedded real-time operating system and LabVIEW development environment are employed to develop the AUV water surface autonomous cruise and dynamic obstacle avoidance system, data image acquisition and communication system, and shore-based intelligent fisheries big data interaction interface. The results of energy consumption analysis and simulation experiments show that the AUV has low energy consumption, and the endurance time is about 77 h when carrying a lithium battery of 5.184 kWh, which can perform autonomous cruising. Tests show that the prototype can effectively communicate with the shore-based host computer, collect water quality information and underwater video images. The AUV for aquaculture monitoring has flexibility in carrying sensors, long endurance, low power consumption, low cost, easy maintenance and upgrading, and is able to meet the demand for three-dimensional movement and long-term fixed-point monitoring of various aquaculture. [ABSTRACT FROM AUTHOR]

In response to the end effect of the permanent magnet linear synchronous motor, this paper proposes an improved modular motor structure. To compute its electromagnetic characteristics, a subdomain model that converts the Cartesian coordinate system into a polar coordinate system through coordinate transformation is further formulated, thus significantly reducing programming difficulty. The analytical results are compared with those of the finite element method and indicate that the subdomain model can accurately consider the effects of end and flux barriers. Moreover, the magnetic field distribution inside the motor is applied to explain the end force abatement, and the suggested flux barrier width is obtained. Finally, the modular structure is applied to a 9-slot, 10-pole permanent magnet linear synchronous motor. The simulation results show that the modular structure can effectively suppress the end effect of the linear motor, and the proposed subdomain model applies to the design of the modular motor.

Abstract Correlation networks derived from multivariate data appear in many applications across the sciences. These networks are usually dense and require sparsification to detect meaningful structure. However, current methods for sparsifying correlation networks struggle with balancing overfitting and underfitting. We propose a module-based cross-validation procedure to threshold these networks, making modular structure an integral part of the thresholding. We illustrate our approach using synthetic and real data and find that its ability to recover a planted partition has a step-like dependence on the number of data samples. The reward for sampling more varies non-linearly with the number of samples, with minimal gains after a critical point. A comparison with the well-established WGCNA method shows that our approach allows for revealing more modular structure in the data used here.

The object of research is energy processes in a hybrid photovoltaic system with a storage battery for the needs of a local object involving the setting of power consumed from the network. The task addressed was to build a mathematical model of energy processes with the function of determining control parameters providing for the possibility of changing control scenarios. The mathematical model of the storage battery has been improved, taking into account the charge modes and discharge currents in terms of accuracy of reproduction of the manufacturer’s specification not worse than 3 %. A structure of the model was proposed with separation of module, which defines control parameters, as well as the schedule of power setting for selected scenarios. A variable is introduced into the model description, which determines the specified power value and ensures the construction of SoС(t) schedule. An additional mode to increase the energy use of the photovoltaic battery and restrictions on the measured value of load power were taken into account. Modeling with a change in time scale was proposed: first, control parameters are determined, followed by modeling in the daily cycle. This eliminates the need for preliminary calculations before modeling and provides the ability to verify the determination of system parameters with subsequent adjustment. A procedure for determining control parameters with power setting and adjusting the model under different control scenarios has been devised. When using archival generation data for the location of the facility, this makes it possible at the design stage to choose an option for implementing the power supply system with the desired indicators. For specific uses, it has been shown that underestimating the power of a photovoltaic battery by only 9 % increases energy costs by 1.72–1.39 times. Overstating power by 16.7 % impairs usage by 13.7 % while reducing costs by 1.4 % to 2.5 %. [ABSTRACT FROM AUTHOR]

The integration of sustainability principles into the structural design and decision-making processes for transportation infrastructure, particularly concerning reinforced concrete precast modular frames (RCPMF), is recognized as crucial for ensuring outcomes that are environmentally responsible, economically feasible, and socially beneficial. In this study, this challenge is addressed, with the significance of sustainable development in modern engineering practices being underscored. A novel approach, which is a combination of multi-objective optimization (MOO) with multi-criteria decision-making (MCDM) techniques, is proposed, tailored specifically for the design and selection of RCPMF. The effectiveness of three repair operators—statistical-based, random, and proximity-based—in optimizing economic, environmental, and social objectives is evaluated. Precise evaluation of objective functions is facilitated by a customized Non-dominated Sorting Genetic Algorithm II (NSGA-II) algorithm, complemented by a detailed life cycle analysis (LCA). The utilization of simple additive weighting (SAW) and fair un choix adéquat (FUCA) methods for the scoring and ranking of the MOO solutions has revealed that notable excellence in meeting the RCPMF design requirements is exhibited by the statistical-based repair operator, which offers solutions with lower impacts across all dimensions and demonstrates minimal variability. MCDM techniques produced similar rankings, with slight score variations and a significant correlation of 0.9816, showcasing their consistent evaluation capacity despite distinct operational methodologies.

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Copyright of En Blanco: Revista de Arquitectura is the property of Universidad Politecnica de Valencia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: The human brain could be modeled as a complex network via functional magnetic resonance imaging (fMRI), and the architecture of these brain functional networks can be studied from multiple spatial scales with different graph theory tools. Detecting modules is an important mesoscale network measuring approach that has provided crucial insights for uncovering how brain organizes itself among different functional subsystems. Despite its successful application in a wide range of brain network studies, the lack of comprehensive reliability assessment prevents its potential extension to clinical trials. Methods: To fill this gap, this paper, using resting-state test-retest fMRI data, systematically explored the reliabilities of five popular network metrics derived from modular structure. Considering the repeatability of network partition depends heavily on network size and module detection algorithm, we constructed three types of brain functional networks for each subject by using a set of coarse-to-fine brain atlases and adopted four methods for single-subject module detection and twelve methods for group-level module detection. Results: The results reported moderate-to-good reliability in modularity, intra- and inter-modular functional connectivities, within-modular degree and participation coefficient at both individual and group levels, indicating modular-relevant network metrics can provide robust evaluation results. Further analysis identified the significant influence of module detection algorithm and node definition approach on reliabilities of network partitions and its derived network analysis results. Discussion: This paper provides important guidance for choosing reliable modular-relevant network metrics and analysis strategies in future studies. [ABSTRACT FROM AUTHOR]

High‐dimensional classification is a fundamentally important research problem in high‐dimensional data analysis. In this paper, we derive a nonasymptotic rate for the minimax excess misclassification risk when feature dimension exponentially diverges with the sample size and the Bayes classifier possesses a complicated modular structure. We also show that classifiers based on deep neural networks can attain the above rate, hence, are minimax optimal. [ABSTRACT FROM AUTHOR]

This paper proposes a new generalized switched-inductor-capacitor module for a non-isolated dc-dc converter with low voltage dc source applications. Further, the proposed module can be extended to an $n$ number of modules to achieve high voltage gain. The derived structure has low voltage stress on power components. This structure benefits the designer by allowing him/her to choose a low $r_{DS}$ (ON) switch due to the low voltage stress across the semiconductor devices, resulting in high efficiency and low cost. In most dc/dc converters, the voltage stress on the output diode will equal the output (high) voltage ( $V_{o}$ ). But in the case of the proposed topology, the diode voltage will be the difference between $V_{o}$ and the input voltage ( $V_{g}$ ), which eases the reverse recovery problem. The key metrics of the derived topology, such as component count, voltage stresses, and gain factor, are analyzed to compare with similar existing topologies. The scaled down prototype setup is developed for 200 W with an efficiency of 93%. Finally, various experimental results are discussed for the different duty cycles.

PRECISE, Photonic hybRid EleCtromagnetIc SolvEr, is a Matlab-based library to model large and complex photonic integrated circuits. Each circuit is modularly described in terms of waveguide segments connected through multi-port nodes. Linear, nonlinear, and dynamical phenomena are simulated by solving the system of differential equations describing the effect to be considered. By exploiting the steady-state approximation of the electromagnetic field within each node device, the library can handle large and complex circuits even on desktop PCs. We show that the steady-state assumption is fulfilled in a broad number of applications and we compare its accuracy with an analytical model (coupled mode theory) and experimental results. PRECISE is highly modular and easily extensible to handle equations different from those already implemented and is, thus, a flexible tool to model the increasingly complex photonic circuits.

Hybrid excited flux switching linear machines (HEFSLM) are attracting attention in rail transit applications due to their high thrust force density, power density, and efficiency. more importantly, their flux controlling ability gives them an edge over permanent magnet machines, which possess constant flux. This paper investigates a modular mover HEFSLM (MMHEFSLM) with concentrated armature and field windings. The concentrated windings result in thrust force ripples but reduce the copper losses. The modular structure of the mover helps in achieving fault-tolerant ability. The volume of PM is significantly reduced, which is rare-earth material and its price is rising progressively. JMAG in-built genetic optimization is utilized to refine the leading CAD parameters thereby improve performance compared to the initial design. The fault-tolerant ability of the proposed machine is verified by the phase's inductance calculation. Finally, based on the electromagnetic performance, the proposed MMHEFSLM is compared with conventional design in the literature. [ABSTRACT FROM AUTHOR]

• A design method for multi-loop closed-chain mechanism(MLCCM) is proposed. • The 4-RSPCR MLCCM and a multi-module morphing wing mechanical network are proposed. • DOF of the mechanism is carried out by the loop connectivity matrix. • The kinematic models of the multi-module morphing wing mechanism are developed. • A prototype of the morphing wing mechanism is developed and validated the motion principle. Innovative design and investigation into multi-configurable morphing wing mechanism (MWM) have been focused on meeting the evolving needs of morphing aircraft with extensive spatial and velocity domains. In this paper, a design methodology for multi-loop closed-chain mechanism (MLCCM) involved the substitution of Bennett mechanism links with sub-mechanisms, and an innovative design of 4-RSPCR MLCCM is proposed based on the method, incorporating equivalent spherical mechanism and group theory. Subsequently, a multi-module morphing wing mechanical network consisting of the 4-RSPCR MLCCM is proposed, and the degrees of freedom (DOF) for the multi-module MWM is analyzed using graph theory. In addition, kinematic models for single module mechanism are established, and research on kinematic modeling methods for multi-module mechanisms is conducted. Finally, a prototype of a six-module MWM is constructed, and deformation experiments is conducted. The results show that the proposed innovative mechanisms and the novel multi-module morphing wing mechanical network facilitate the serialized design for various wing planar shapes. Furthermore, these mechanisms enable multi-configurational deformations, including bi-directional bending and variable span. These findings lay the groundwork for fundamental research and engineering applications of morphing wings in morphing aircraft. [ABSTRACT FROM AUTHOR]

Helicobacter pylori is a pathogenic bacterium that causes gastric ulcers and cancer. Among the diverse virulence genes of H. pylori , the IceA gene was identified to be expressed upon adherence to host cells. The IceA gene has two alleles, iceA1 and iceA2 , which encode completely different proteins. IceA1 protein was shown to exert endonuclease activity, whereas IceA2 has never been analyzed at the molecular level. Based on a sequence analysis, IceA2 proteins differ in length depending on the strain and are classified into five groups (A-E). To structurally characterize IceA2, we determined the crystal structure of group-D IceA2 (IceA2 sD) and performed a modeling-based comparative analysis of IceA2 groups. IceA2 sD consists of three β-sheet repeats and serially arranges them like the β-propeller structure of the WD40 domain. However, each β-sheet of IceA2 is stabilized using a unique structural motif that is not observed in WD40. Moreover, IceA2 sD lacks an additionally appended β-strand and does not form the Velcro-like closure of WD40. Therefore, IceA2 sD adopts a curved rod-like structure rather than an enclosed circular structure in WD40. IceA2 proteins contain 1-4 β-sheet modules depending on the groups and are modeled to be highly diverse in size and shape. • IceA2 proteins from Helicobacter pylori strains are classified into groups A-E. • We determined the crystal structure of group-D IceA2 (IceA2 sD). • IceA2 sD adopts a curved rod-like one-domain structure with three β-sheet repeats. • IceA2 sD arranges its β-sheet repeats similarly to the WD40 β-propeller structure. • IceA2 proteins are modeled to contain 1-4 β-sheet repeats depending on their groups. [ABSTRACT FROM AUTHOR]

The application of the nanosecond pulsed electric field (nsPEF) for biomedical treatments has gained more interest in recent decades due to the development of pulsed power technologies which provides the ability to control the electric field dose applied during tests. In this context, the proposed paper describes a new architecture of solid-state high-voltage pulse generators (SS-HVPG) designed to generate fully customised sequences of quasi-rectangular pulses. The idea is based on the combination of semiconductor switches (IGBT/MOSFET) known for their flexibility and controllability with special magnetic switches to build compact and modular generators. The proposed structure is inspired by the most known pulse generator of Marx, but mixes its two variants for negative and positive polarities. Thus, the polarity of the generated pulses can be freely selected. In addition to that, the use of IGBTs/MOSFET ensures a tunable repetition rate and pulse width. The capacitors are charged via a series of magnetic switches and a flyback DC–DC converter which provides fast and efficient charging and also an adjustable amplitude of the output pulses. The design can be easily simplified giving two other modified structures, based on the same idea, for mono-polar operating (only positive or only negative pulses) with a reduced number of switches. A SPICE simulation of the generator and results of experimental tests carried out on a three stages generator are presented. The obtained results confirm the operating principle and the claimed performances of the new structure. [ABSTRACT FROM AUTHOR]

A novel topology of the modular multilevel inverter with the ability to boost the input voltage is proposed in this work. The proposed single-source structure requires neither any external controller nor transformers to balance the voltages of the capacitors. In addition, the output voltage polarity of the inverter is generated inherently with a low switching frequency, making it suitable for both residential and industrial applications. The Nearest Level Modulation (NLM) is applied to control the operation of the inverter. The detailed comparative analysis of the proposed inverter with other inverters indicates that the proposed structure can produce similar voltage levels with a fewer number of elements and less voltage stresses. Moreover, to verify the performance of the proposed converter, a single-phase 13-level prototype was implemented in the laboratory environment and the test results were compared to the simulation ones. The advantages of low harmonic contents with Total Harmonic Distortion (THD) of 6.5% and 92.69% efficiency make the proposed inverter appropriate for applications with a limited number of low voltage sources. [ABSTRACT FROM AUTHOR]

Orbital angular momentum (OAM) carrying vortex beams has been studied and realized using different methods. However, the designed devices are usually capable of generating fixed OAM modes. Here, the concept of a modular radiating system based on tightly cascaded transmitarrays (TAs) provi- ding a compact and user-accessible modular radiating system suitable for affordable detecting and imaging systems is presented. The TA is based on a novel compact unit cell. The unit cell characteristics are explained and then cascaded for the TAs’ operation. Several prototype TA modules are realized, and their interactions for OAM mode interconversion are investigated. A restricted method for determining the OAM mode purity of the generated beams is employed. The simulated and experimental results are consistent with the theory, verifying the employed strategy. [ABSTRACT FROM AUTHOR]

This work introduces a novel concept of modular, shape-adaptable sandwich panel with a distributed actuation system based on shape memory alloys (SMA). The panel consists of a modular arrangement of rigid cells connected with compliant active joints. Each joint hosts a SMA wire, which can be controlled independently, enabling the panel to achieve multiple shapes and complex curvatures with a single design. A numerical model of the actuators is developed combining the SMA model proposed by Brinson with a finite element model of the compliant joints, and validated against experimental results. Further, a demonstrator of the panel is manufactured and tested implementing four different actuation patterns and measuring the final shapes with a digital image correlation system. The results prove the capability of the proposed concept to achieve both in plane and out-of-plane deformations in the order of millimeters to centimeters, and to reproduce shapes with double curvatures. With the possibility to integrate sensors and additional components inside the core, the proposed shape-adaptable panel can be used to realize smart structures, which might be used for morphing aerodynamic surfaces or reconfigurable space structures. [ABSTRACT FROM AUTHOR]