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Due to the low voltage and high randomness of renewable energy, high-performance grid-connected converters are needed. With the advantages of a high boost ratio, flexible design, and simple control, the Y-Source Converter (YSC) is widely concerned. However, there are a few drawbacks to the traditional Y-source converter, including significant switching stress, voltage voltage overshoot, and discontinuous current. To solve the problems above, a series of improved topologies are proposed. Moreover, the voltage gain, current ripple, and soft switching characteristics have also been optimized. So far, the existing literature lacks the collation and comparison of different topologies of Y-source, as well as the analysis of its evolution process. Therefore, this paper provides a comprehensive overview of Y-source converters' topologies. According to their features and applications, different topologies are classified and described, leading to guidance for the selection of YSCs under different scenarios. Meanwhile, the working principle, evolution process, and vital issues are analyzed. By revealing their deductive rules, valuable suggestions are provided for the future development of YSCs. [ABSTRACT FROM AUTHOR]

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The positions of sensor nodes in wireless sensor networks (WSNs) plays important role in order to achieve optimum values of various parameters, such as coverage, localization, etc. WSNs are used in every field such as in agriculture, military etc. and to achieve optimum performance of WSNs in these fields the sensor nodes are required to deploy at optimized positions. In this paper the jaya-sine cosine optimization algorithm (Jaya-SCOA) is proposed to deploy the sensor nodes at optimum positions and to increase the coverage of sensor nodes. Further the sensor nodes are deployed in three different topologies such as C shape, outer boundary and random topology and coverage rate is computed for all topologies. The major goal of the paper is to find the best topology for deploying the sensor nodes in WSNs and to enhance the coverage of nodes. The simulation results of proposed Jaya-SCOA is compared with fruit fly optimization algorithm (FFOA) and bat optimization algorithm (BOA) for all topologies in terms of maximum and minimum coverage, standard deviation and mean coverage rate. The simulation results demonstrate that for all topologies the coverage rate of Jaya-SCOA is higher than that of FFOA and BOA and average coverage rate of Jaya-SCOA for random topology is increased by 14.55% and 27.04% as compared to outer boundary and C shape topology, respectively. Therefore, the random topology is the best topology as compared to other topologies and Jaya-SCOA is effective than BOA and FFOA for all topologies in terms of coverage and stability. [ABSTRACT FROM AUTHOR]

Grid-connected converters (GCCs) are used extensively for the integration of DC power sources with AC power sources. However, since it is a complex topic, there are many possibilities for regulating grid-injected currents, as well as different modulation techniques for generating full-bridge PWM voltages. The control techniques are directly related to the type of output filter, as well as to the topology of the converter, since a complex plant can require more sophisticated controllers to keep the system stable, and with good regulation performance. Furthermore, a discussion of the applicability of these converters in weak and very weak grids with high inductance content has recently been growing, which adds a greater degree of complexity to the control structure of the converter. In this brief overview are outlined some topics about topologies, output filters, and control, focusing on the current regulation of grid-connected converters. In addition, a discussion of the main challenges and critical areas in operating on weak and very weak grids is also presented. [ABSTRACT FROM AUTHOR]

Micro-lattice structure is a modern concept in cellular materials, which merges valuable mechanical attributes of material with smart geometrical directions. It is light in weight and consists of high energy absorption capacity, high strength and less vibration than other cellular materials. The micro-lattice structure is another type of cellular solid's materials containing slender lattice parts known as strut and is categorized according to their cell arrangement. Due to the above properties nowadays, it is very popular for industrial applications like medical and bioengineering, aviation, automation and robotics. There are various techniques available for manufacturing micro-lattice structure. The simple, rapid and scalable fabrication of micro-lattice structure is achieved using additive manufacturing. Even geometrically intricate parts, complex assemblies can easily accommodate this lightweight technology. This paper presents an overall view of the micro-lattice structure concerning different topologies, various manufacturing methods, and different materials used. This paper also discusses how the variation of the above parameters can perk up the micro-lattices working notably, from a mechanical and application outlook. The attributes of micro-lattice structures and the foremost later finite element analysis models developed by different researchers for analyses of different properties have been also discussed here. This paper surveys the challenges confronted by various researchers and proposes future insight about micro-lattice structures required to progress their utilization in lightweight applications. [ABSTRACT FROM AUTHOR]

Summary: Series‐connected lithium battery packs are widely adopted in industries such as electrical vehicles and large‐scale energy storage systems. It is necessary to configure an equalization system for them to reduce the inconsistency of single cells, to ensure the battery pack cycle capacity. Although many novel active converters have been proposed for equalization, there still lacks systematic analyses on variables, topologies, and modular methods. Therefore, this paper provides a systematic review on the above aspects. Initially, an overall summary is present on current variables for equalization control. Second, the dominant structures are divided into cell‐to‐cell, cell‐to‐pack, and pack‐to‐pack topologies, and their characteristics are pointed out for comparison. And then, the modular methods, including single‐layer‐based, multi‐layer‐based, and hybrid integrations are evaluated via graph theory. Some key issues and potential research directions are given, which are expected to offer assistance on the selection of appropriate variables and topologies for equalization systems in the future. [ABSTRACT FROM AUTHOR]

There are various ways to derive multilevel converter topologies as pointed out by the author's previous work. This letter proposes a voltage-source generalized multilevel converter topology that unifies several generalized multilevel topologies and also incorporates bidirectional switches. Most of the known multilevel topologies can be derived from this topology and new topologies can also be derived from it. Examples have been given in this letter. This generalized topology helps to understand complicated converter topologies, especially those with bidirectional switches and it can also be used to determine the voltage requirements/ratings of the devices in various topologies. This letter has summarized the rules to derive topologies from this generalized topology and provides experimental results for one of the derived multilevel converter examples. It is expected that new topologies can be inspired or derived from this letter and used for existing and emerging applications, with this letter as a milestone in the research of multilevel converter topologies. [ABSTRACT FROM AUTHOR]

The controlled and efficient synthesis of polymers with tailored topologies is challenging but important for exploring structure/property research. Herein, we proposed a concept of macro-latent monomer to achieve the controlled growth of polymer topologies. The macro-latent monomer was installed by a dynamic furan/maleimide covalent bond at the chain terminal. One-shot reversible addition-fragmentation chain transfer (RAFT) polymerization of styrene and the macro-latent monomer created controlled growth of polymer topologies. Low temperature such as 40 °C could not activate the macro-latent monomer and thus the polymerization created the homo-polystyrene. By contrast, high temperature of ∼110 °C activated the macro-latent monomer, and a maleimide-terminated macro-monomer was released via the retro-Diels Alder reaction. This macro-monomer immediately joined the cross polymerization with styrene and thus produced the side chains. By delicately manipulating the polymerization temperature, the predetermined placement of the macro-latent monomer-derived polymeric side-chains created controllably growing topologies, including star-, π-shaped, and density-variable grafting copolymers. This work paved a new way for creating on-demand topologies and would greatly enrich the topology synthesis. [ABSTRACT FROM AUTHOR]

Multilevel converters have gained popularity in both medium voltage and low voltage applications. To find out the connections between various multilevel voltage-source converter topologies and to reveal how to obtain new topologies, this paper has presented four methods to derive multilevel converter topologies. Many existing topologies as well as new topologies can be derived with the methods presented in this paper. The fundamental characteristics of the multilevel converters which determine their usability such as dc-link neutral point voltage balancing and flying capacitor voltage control are also investigated in this paper with a mathematical model and an example. It is expected that more new topologies will be invented based on the work in this paper for emerging applications. [ABSTRACT FROM AUTHOR]

Wavelength division multiplexing (WDM)-based Passive Optical Networks (PON) has gained attention due to the massive growth in bandwidth demand resulting from the increased number of users, utilisation of bandwidth-hungry applications, network protection, reliability, survivability, scalability and mobility advents. Multiple architectures were proposed in the literature to achieve credibility and sustainability in WDM-PON networks. To identify the best approach, the current study presented a comparative analysis of recent and the most deployed WDN-PON topologies that mainly comprises tree, star, ring, and wheel. The study also discussed the advantages and disadvantages of every WDM-PON topology while outlining the research gap for future directions. [ABSTRACT FROM AUTHOR]

The important energy requirements for the desalination process impose especially in autonomous and decentralized plants supplied by Renewable Energy Sources (RES). In this paper, five alternative energy generation topologies of Reverse Osmosis desalination process are evaluated. The proposed topologies assessed in terms of economic, environmental, technological and societal indices are compared using multi-criteria analysis, namely the Analytic Hierarchy Process (AHP) and the Preference Ranking Organization Method for Enrichment of Evaluations (PROMETHEE). Ranking of topologies resulted in the selection of direct connection and hybrid configuration as optimum solutions. In case economic priorities prevail diesel generation should also be considered. [ABSTRACT FROM AUTHOR]

Energy storage concept that supports important technologies for electrical systems is well established and widely recognized. Several energy storage techniques are available, including an electrochemical energy storage system used to support electrical systems. These storage systems require interfaces based on power electronic converters for interconnection with an electrical system. This paper reviews the literature covering the various types of interfaces developed for electrochemical energy storage systems. Different electrochemical energy storage devices and their specificities regarding to integration with the electrical systems are described. . The various power converter interfaces that can be used for electrochemical energy storage systems are presented. These interfaces have been divided into standard, multilevel and multiport technology. The main characteristics and specificity of each topology considering its application to electrochemical energy storage systems are presented. The review also covers the smart storage concept and the requirements of the interface to integrate the electrochemical energy storage devices upon this concept. [ABSTRACT FROM AUTHOR]

To solve the grand challenges in contemporary chip design, such as process-to-core mapping, energy reduction, and maintenance of programmer/hardware abstraction, we advocate for self-optimizing (emergent) networks-on-chip (NoC). In these networks, topology and information flow adapt dynamically to maximize the network throughput or minimize the network latency via distributed application of microrules. In this paper, we introduce the concept of emergent small-world NoCs and discuss novel design decisions, e.g., Skip-links, that improve performance and reduce energy consumption of multicore systems. More precisely, we demonstrate that our proposed solution is able to adapt to a wide range of traffic patterns and provide reductions in data hop count of up to 20 percent while maintaining energy and area costs. We show how emergent networks can be useful for on-chip processor-to-processor communications, and also demonstrate how SoC and off-chip I/O traffic may be optimized for latency and critical load. [ABSTRACT FROM PUBLISHER]

A complete family of Cayley graphs of degree four, denoted as L-networks, is considered in this paper. L-networks are 2D mesh-based topologies with wrap-around connections. L-networks constitute a graph-based model which englobe many previously proposed 2D interconnection networks. Some of them have been extensively used in the industry as the underlying topology for parallel and distributed computers of different scales. Tori, twisted and doubly twisted tori, toroidal diagonal meshes, chordal rings, and circulant graphs are, among others, members of the L-network family. Therefore, many results obtained in previous studies on these networks can be deduced from the general framework presented in this work. In addition, the network model presented in this work allows for new results on the domain of low-degree interconnection networks. Particularly, closed expressions for the graph distance properties have been derived and an optimal routing algorithm of constant complexity is provided. Since symmetry has a big impact on network performance, we have also identified which L-networks are symmetric by studying their group of automorphisms. Finally, a very simple model that predicts the performance of L-networks is also presented. Such model has been contrasted with empirical evaluation. [ABSTRACT FROM AUTHOR]

Two novel zinc coordination polymers {[Zn(PhCOO)2(bmix)]}n 1 and {[Zn(ada)(bmix)]·(H2O)2}n 2 (bmix = 1,4-bis(2-methylimidazole-1-ylmethyl)benzene, H2ada = adipic acid), were obtained by the hydrothermal reactions of bmix and zinc acetate with two carboxylate anions, respectively. Structural analyses show that complex 1 possess a one-dimensional helix chain structure, 2 takes two-dimensional corrugated (4,4) layer motif. The structural differences of two complexes indicate that organic carboxylate anions play important roles in the formation of such zinc(II) coordination architectures. [ABSTRACT FROM AUTHOR]

Vital signs detection by means of several topologies based on Doppler radar are proposed in this paper with the aim of overcoming the problem of null detection. They are based on phase and frequency diversity. The proposed topologies are an alternative to I/Q demodulation and double-sideband transmission. Four topologies are proposed, three of them based on phase diversity and one based on frequency diversity. The first topology is based on using two phase-shifted receivers. The second one is based on a physical antenna displacement between two receivers. A third system with a dynamic phase variation is also presented, which permits to work with only one receiver. The last topology is a radar with frequency diversity within the 2.4 GHz ISM band, which permits a dynamic change of the frequency dynamically in order to place the receiver always in a maximum. A system to empirically characterize nulls is also developed to validate the proposed topologies. [ABSTRACT FROM PUBLISHER]

Abstract: Self-penetrating coordination networks have recently been demonstrated as an important family of coordination polymers with new topologies and properties. However, the design and control of self-penetrating systems is still an enthralling challenge. In this review, we present the topological types of self-penetrating coordination networks, mainly with single-connectivity, and summarize their designing and constructing strategy. [Copyright &y& Elsevier]

In 2005, Professor Gudder presented 25 open problems of sequential effect algebras, and in this paper, we survey the development of these problems, and we point out two new interesting topics in the sequential effect algebras, too. [ABSTRACT FROM AUTHOR]

A systematic method to derive the topology is presented for a family of forward converters with inherent demagnetizing features in high-power application. A basic forward cell concept is proposed with three basic forward cells, named as, forward positive cell, forward negative cell, and forward composite cell, respectively. All cells consist of active switch, diode, and transformer, and are the basic building blocks of a forward converter that uses auxiliary diodes to realize natural magnetizing reset. The topology derivation rules are proposed. Some existing and novel forward topologies are constructed as examples. The forward converters, built in such way, illustrate features such as natural-magnetizing reset, recycle of leakage and magnetizing energy, low voltage stress of active switch, zero-voltage switching, etc. An input series output parallel forward converter, thus generated, is analyzed in detail, as example, with experimental results given. [ABSTRACT FROM PUBLISHER]

This is the second paper in the series on shape decompositions and their use as shape approximations. This timewe investigate hierarchical and topological shape decompositions or hierarchies and topologies.We showed earlier that bounded decompositions behave the same way as shapes do. The same holds for hierarchies and topologies, which are special kinds of bounded decompositions. They are distinguished by their algebraic structures, which have many important properties to facilitate their application as shape approximations. We provide an account of their properties with an emphasis on their application. [ABSTRACT FROM AUTHOR]

The paper presents the essential connections between modal-like operators, topologies and fuzzy sets. We show, for example, that each fuzzy set determines a preorder and an Alexandrov topology, and that similar correspondences hold also for the other direction. Further, a category for preorder-based fuzzy sets is defined, and it is shown that its equivalent subcategory of representatives is isomorphic to the categories of preordered sets and Alexandrov spaces. Moreover, joins, meets and complements for the objects in this category of representatives are determined. This suggests how to define for fuzzy subsets of a certain universe the lattice operations in a canonical way. [Copyright &y& Elsevier]

The ideals of effect algebras induce a topology on effect algebras. The operations ? and ? of effect algebras are continuous with respect to this topology. [ABSTRACT FROM AUTHOR]

Two erbium-doped fiber ring lasers (EDFRLs) wvith simultaneous emission at four different wavelengths are demonstrated. Both systems employ fiber Bragg gratings (FBGs) to select the operation wavelengths within the ring. The sensing capability of the FBGs has been taken advantage of, allowing for the sources to be used as sensor multiplexing schemes. The first system employs four FBGs in a tree filter topology, achieving four output channels with -5 dBm power each. The second system comprises an in-line filtering topology with active fiber segments within the filter. This second source yields 2-dBm output signals and allows for a higher number of lines to be easily added to the system. A comparison between both topologies is carried out, and their capability for sensor multiplexing is demonstrated [ABSTRACT FROM PUBLISHER]

The use of power electronic converters is essential for the operation of Switched Reluctance Machines (SRMs). Many topologies and structures have been developed over the last years considering several specific applications for this kind of machine, improving the control strategies, performance range, fault-tolerant operation, among other aspects. Thus, due to the great importance of power electronic converters in such applications, this paper is focused on a detailed review of main structures and topologies for SRM drives. The proposed study is not limited to the classic two-level power converters topologies dedicated to the SRMs; it also presents a review about recent approaches, such as multilevel topologies and based on impedance source network. Moreover, this review is also focused on a new class of topologies associated to these machines, namely the ones with fault-tolerant capability. This new category of topologies has been a topic of research in recent years, being currently considered an area of great interest for future research work. An analysis, taking into consideration the main features of each structure and topology, was addressed in this review. A classification and comparison of the several structures and topologies for each kind of converter, considering modularity, boost capability, number of necessary switches and phases, integration in the machine design, control complexity, available voltage levels and fault-tolerant capability to different failure modes, is also presented. In this way, this review also includes a description of the presented solutions taking into consideration the reliability of the SRM drive. [ABSTRACT FROM AUTHOR]