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The purpose of this paper is to propose a novel serial structure repetitive control scheme for shunt active power filter (SAPF) to improve the steady-state accuracy and dynamic performance of SAPF. The novelty of this scheme lies in the reconfiguration of the pole of repetitive control internal model, so that the dynamic response of the repetitive control is improved greatly.

By analyzing the mathematical model of repetitive control, the repetitive control delay can reduce by giving up the needless poles of the internal model, and the general mk + i repetitive control can be designed through the pole configuration method. The controller can track a set of specific order harmonics.

The experimental results are coincident with the theoretical analyses, which prove the effectiveness of the proposed method on harmonic suppression and great performance in dynamic response.

An APF prototype has been designed with the serial structure repetitive control proposed in this paper, and it can successfully eliminate the harmonics current of nonlinear load with faster dynamic response. Moreover, the proposed controller can be applied to any three-phase system for fast dynamic response and high tracking accuracy.

In this paper, the mathematical model of the repetitive control for specific set of harmonica is developed. A novel serial structure repetitive control is designed, so that the SAPF can eliminate the fundamental reactive current and specific order harmonics and speed up the dynamic response of the repetitive control.

Modern wireless communications need novel microwave components that can be effectively used for high data rate and low-power applications. The operating environment decides the severity of the noise coupled to the transceiver system from the ambient environment. In a deep fading environment, narrowband systems fail where the wideband systems come for rescue. Thus, the microwave components are ought to switch between the narrowband and wideband states. This paper aims to study the design of a bandpass filter to meet the requirements by appropriately switching between the dual narrowband frequencies and single ultra-wideband frequency band.

The design and implementation of a compact microwave filter with reconfigurable bandwidth characteristics are presented in this paper. The proposed filter is constructed using a hexagonal ring with shorted perturbation along one corner. The filter is capacitively coupled to the external excitation source. External stubs are connected to the corners of the hexagonal resonator to obtain dual passband characteristics centred at 2.1 and 4.5 GHz. The external stubs are configured to achieve bandwidth reconfigurable characteristics. PIN diodes are used with a suitable biasing network to obtain reconfiguration. In the reconfigured state, the proposed two-port filter offers a continuous bandwidth from 2.1 to 5.9 GHz. The roll-off rate along the band edges is improved by increasing the order of the filter.

The proposed filter operates in two states. In state 1, the filter operates with dual frequencies centred around 2 and 4.5 GHz with insertion loss less than <1 dB and return loss greater than 13 dB with a peak return loss of 21 and 31 dB at 2.1 and 2.15 GHz, respectively. In state 2, the filter operates from 2.1 to 5.9 GHz with insertion loss less than 1 dB and return loss greater than 12 dB. The filter exhibits four-pole characteristics with a peak return loss greater than 22 dB. Thus, the fractional bandwidth of the proposed filter is 17% and 16% in state 1, whereas the fractional bandwidth is 95% in state 2.

The proposed filter is the first of its kind to simultaneously offer miniaturization and bandwidth reconfiguration. The proposed second-order filter has two-pole characteristics in the narrowband state, whereas four-pole characteristics are realized in the wideband state. The growing interest in 4G and 5G wireless communications makes the proposed filter a suitable candidate for operation in the rich scattering environment.

Partial shading causes significant power decreases in the PV systems. The purpose of this paper is to address this problem, connectivity regulation is designed to reduce partial shading problems.

In this approach, the partial shading was estimated and dispersed evenly on the whole array by global shade dispersion technique (GSD). The grey wolf algorithm was implemented for the interconnection of arrays by an efficient switching matrix.

After the implementation of the GSD technique using a grey wolf algorithm, the performance under different shading conditions was analyzed using the MatLab simulation tool. The results were compared with total cross-tied (TCT), Su Do Ku and the proposed method of reconfiguration, where the proposed method improves the maximum power of the PV system appropriately.

This methodology uses any size of PV systems.

Replacement of conventional energy systems with renewable energy systems such as solar helps the environment clean and green.

The GSD interconnection scheme using the grey wolf optimization algorithm has proved an improved output performance compared with the existing TCT and Sudoku based reconfiguration techniques. By comparing with existing techniques in literature, the proposed method is more advantageous for reducing mismatch losses between the modules of any size of the PV array with less operating time.

Reports on the implications for facilities managers attendant to selecting among various service distribution methods, in particular wire and air distribution methods. Details the performance capabilities of various distribution methods. Concludes that fully functional, efficient buildings are just as critical to financial performance as the salesforce, engineering or manufacturing.

The purpose of this paper is to apply the theory of sociomateriality to exhibit how the social and material are entangled and (re)configured over time and in practice in a particular organization of study.

The authors conduct an ethnographic case study of the North-South metro line project in Amsterdam and use the methods of participant-observation, in-depth interviewing and a desk study.

The authors showcase the process of sociomaterial entanglement by focussing on the history and context of the project, the agency and performativity of the material and sociomaterial (re)configuration via ritual performance. The authors found the notion of performativity not only concern the enactment of boundaries between the social and material, but also the blurring of such boundaries.

Sociomateriality theory remains difficult to grasp. The implication is the need to provide new lenses to engage this theory empirically.

The authors provide a multi-layered lens for organization researchers to engage sociomateriality theory at a contextual, organizational and practice level.

Insights from a historical and contextual perspective can help practitioners to become aware of the diverse and dynamic ways in which social and material entities are entangled and (re)configured over time and in practice.

The authors provide a unique empirical account to exhibit the entanglement and (re)configuration between the social and material in a particular organization of study. This paper studies a tangible organizational setting whereas prior research in sociomateriality mainly focussed on routines in IT and IS. Finally, the authors suggest the ethnographic method to study sociomaterial entanglement from a historical and contextual perspective.

Weak regional commercial and productive integration and monetary dependence on the economic poles are evidence of the consolidation of Latin America's peripheral position in the world economy. This research analyzes different monetary initiatives launched individually or collectively by countries in the region to alleviate this position, such as the petro, the SUCRE, or El Salvador's bet on the legal acceptance of bitcoin as a payment instrument. After identifying some of their limitations, we propose some basis for monetary coordination with which to advance in the dynamization of productivity and trade complementarity of the countries of the region.

This article is aims to inform aircraft propulsion system designers of the implications which fundamental power distribution design assumptions have on the effectiveness and viability of turboelectric distributed propulsion (TeDP) systems. Improvements and challenges associated with selecting alternating or direct current for normal- and superconducting distribution systems are presented. Additionally, for superconducting systems, the benefits of bi-polar DC distribution are discussed, as well as the implications of operating voltage on the mass and efficiency of TeDP grid components.

The approach to this paper selects several high-level fundamental configuration decisions, which must be made, and it qualitatively discusses potential implications of these decisions.

Near term TeDP architectures which employ conventionally conducting systems may benefit from alternating current (AC) distribution concepts to eliminate the mass and losses associated with power conversion. Farther term TeDP concepts which employ superconducting technologies may benefit from direct current (DC) distribution to reduce the cryocooling requirements stemming from AC conduction losses. Selecting the operating voltage for superconducting concepts requires a divergence from the present day criteria employed with terrestrial superconducting transmission systems.

The criteria presented in the paper will assist in the early conceptual architecting of TeDP systems.

The governing principles behind the configuration of multi-MW airborne electrical microgrid systems are presently immature. This paper represents a unique look and the motivating principles behind fundamental electrical configuration decisions in the context of TeDP.

The purpose of this paper is to explore the role of organisational capabilities (dynamic and operational) in the formation of value networks in the context of public transport services.

The theoretical argument is substantiated with qualitative data from four narratives on value network formations in the Swiss public transport system. These four narratives cover two types of new value networks: incremental improvements in established value networks; and radical leaps in emerging value networks.

These two types of new value networks entail the co‐evolution of different dynamic and operational capabilities.

The study is limited by the qualitative research approach.

Public transport operators can utilise the findings on organisational capabilities to guide incremental improvements in their existing value network and/or radical leaps into an emerging value network.

Governments should not only seek to increase transport capacity, but also aim to develop value networks to enhance public transport service experiences.

The paper applies value‐network thinking to public transport services. It offers a comprehensive framework to help organisations manage the formation of value networks. The results provide testable propositions that can be used to guide future research.

Direct digital manufacturing (DDM) is conceived of as either disrupting the entire manufacturing economy or merely enabling novel production. The purpose of this paper is to introduce an alternative where DDM coexists with and complements traditional mass production. When multiple parts run across one manufacturing line, DDM can isolate variability associated with low volume part production and may be preferred to mass production despite being expensive. If DDM complements rather than cannibalizes mass production, this alters the understanding of who adopts DDM, the products built with DDM, and DDM’s long-term supply chain implications.

This invited paper explores a DDM rollout scenario and qualitatively assesses potential supply chain reconfigurations.

The analysis recognizes that existing manufacturers with heterogeneous bills-of-material may develop DDM capabilities to isolate disruptive, low-volume production from scalable mass production. Developing DDM competence and raw material scale advantages, these manufacturers become the locus of change in a manufacturing landscape increasingly characterized by multi-product DDM supercenters.

Extant research largely focusses on two potential reasons for DDM adoption: cost-per-unit and time-to-delivery comparisons. The authors explore a third driver: DDM’s capacity to isolate manufacturing variability attributable to low volume parts. Relative to the extant literature, this suggests a different DDM rollout, different adopters, and a different supply chain configuration. The authors identify mass manufacturing variability reduction as the mechanism through which DDM may be adopted. This adoption trajectory would eventually enable a supply chain transition in which spare parts inventory migrates from finished goods at proprietary facilities to raw materials at generalized DDM supercenters.