With the rapid advancement of cyber-physical systems, Digital Twin (DT) is gaining ever-increasing attention owing to its great capabilities to realize Industry 4.0. Enterprises from different fields are taking advantage of its ability to simulate real-time working conditions and perform intelligent decision-making, where a cost-effective solution can be readily delivered to meet individual stakeholder demands. As a hot topic, many approaches have been designed and implemented to date. However, most approaches today lack a comprehensive review to examine DT benefits by considering both engineering product lifecycle management and business innovation as a whole. To fill this gap, this work conducts a state-of-the art survey of DT by selecting 123 representative items together with 22 supplementary works to address those two perspectives, while considering technical aspects as a fundamental. The systematic review further identifies eight future perspectives for DT, including modular DT, modeling consistency and accuracy, incorporation of Big Data analytics in DT models, DT simulation improvements, VR integration into DT, expansion of DT domains, efficient mapping of cyber-physical data and cloud/edge computing integration. This work sets out to be a guide to the status of DT development and application in today’s academic and industrial environment.

A state-of-the-art survey of Digital Twin: techniques, engineering product lifecycle management and business innovation perspectives

Wearable devices have found numerous applications in healthcare ranging from physiological diseases, such as cardiovascular diseases, hypertension and muscle disorders to neurocognitive disorders, such as Parkinson’s disease, Alzheimer’s disease and other psychological diseases. Different types of wearables are used for this purpose, for example, skin-based wearables including tattoo-based wearables, textile-based wearables, and biofluidic-based wearables. Recently, wearables have also shown encouraging improvements as a drug delivery system; therefore, enhancing its utility towards personalized healthcare. These wearables contain inherent challenges, which need to be addressed before their commercialization as a fully personalized healthcare system. This paper reviews different types of wearable devices currently being used in the healthcare field. It also highlights their efficacy in monitoring different diseases and applications of healthcare wearable devices (HWDs) for diagnostic and treatment purposes. Additionally, current challenges and limitations of these wearables in the field of healthcare along with their future perspectives are also reviewed.

/pdf/advances-in-healthcare-wearable-devices-4afxoeeunk.pdf

Advances in healthcare wearable devices

The current state of Distributed Renewable Generation, challenges of interconnection and opportunities for energy conversion based DC microgrids

The nine-switch converter has already been proven to have certain advantages, in addition to it s component saving topological feature A nine-switch power converter having two sets of output terminals was recently proposed in place of the traditional back-to-back power converter that uses 12 switches in total . Instead of accepting these tradeoffs as limitations, a nine-switch power conditioner is proposed here that virtually "converts" most of these topological short comings into interesting performance advantages. Despite these advantages, the nine-switch converter has so far found limited applications due to its many perceived performance tradeoffs like requiring an oversized dc-link capacitor, limited amplitude sharing and constrained phase shift between its two sets of output terminals. With an appropriately designed control scheme then incorporated, the nine-switch converter is shown to favorably raise the overall power quality in experiment, hence justifying its role as a power conditioner at a reduced semiconductor cost. Aiming further to reduce its switching losses, an appropriate discontinuous modulation scheme is proposed and studied here in detail to doubly ensure that maximal reduction of commutations is achieved.

/pdf/an-integrated-nine-switch-power-conditioner-for-power-3eyh7d5nko.pdf

An Integrated Nine-Switch Power Conditioner for Power Quality Enhancement and Voltage Sag Mitigation

Vehicle ad-hoc networks (VANETs) are a subclass of mobile ad hoc networks (MANETs). The VANETs communication framework is used to provide communication between moving vehicles in highway and urban road scenarios. Dynamic properties of VANETs, such as high dynamic topology, frequent route failure, high mobility of nodes, and bandwidth constraints, reduce the efficiency of routing. The long length route between source and destination affects the efficiency of the protocol in the form of high overhead, frequent disconnections, high packet loss rate, low packet delivery rate, and low throughput. In this paper, we propose an Enhanced Hybrid Ant Colony Optimization Routing Protocol (EHACORP) to improve the efficiency of the routing process using the shortest path. The shortest path in the proposed protocol has low communication costs and the least number of hops between source and destination vehicles. The EHACORP has two phases. In phase 1, the EHACORP relies on a distance calculation method to compute the distance between vehicles. In phase 2, the source-based ant colony optimization is used to guide the ants to build a shorter path with the least number of hops to transmit data. The shortest path improves the efficiency of protocol in all aspects. The simulation results show that the EHACORP has improved packet delivery rate, throughput, end-to-end delay, routing overhead, and packet loss rate compared to Fuzzy based ant colony optimization (F-ANT), Ad hoc on-demand distance vector (AODV), ant colony optimization routing algorithm (ARA), and AntNet routing protocols.

An enhanced hybrid ant colony optimization routing protocol for vehicular ad-hoc networks

This paper presents a configuration of dual output single-phase current source inverter with six-switches for microgrid applications. The inverter is capable of delivering power to two independent set of loads of equal voltages or different voltages at the load end. The control strategy is based on integral sliding mode control (ISMC). The cyber twin model-based test bench is developed to analyze the performance of the inverter. The cyber twin is a virtual model of the physical system to simulate behaviours. The performance of the inverter is analyzed with a cyber twin model and monitored through the remote system. Also, the inverter is analyzed with different voltage conditions.

/pdf/multi-port-current-source-inverter-for-smart-microgrid-2m5rsqfa0g.pdf

Multi-Port Current Source Inverter for Smart Microgrid Applications: A Cyber Physical Paradigm

This paper presents a review on the application of back-to-back converters in the field of Permanent Magnet Synchronous Generator (PMSG) based Wind Energy Conversion Systems (WECS). The wide applications of the back-to-back converters are power conditioning devices, micro grid, High Voltage Direct Current (HVDC), Renewable energy systems. The intention is to present an overview about the design considerations taken by various researchers in back-to-back converters in the field of Wind Energy Conversion Systems (WECS) and recent developments on it. Generally the configuration of back-to-back converters used are 12 pulse Voltage Source Converters (VSC), 12 pulse Current Source Converter (CSC), 9 Pulse Voltage Source Converter .

/pdf/a-review-on-back-to-back-converters-in-permanent-magnet-22ozbjuqoi.pdf

A Review on Back-to-Back Converters in Permanent Magnet Synchronous Generator based Wind Energy Conversion System

Reliable and continued performance of power Transformer is the key to profitable generation and transmission of electric power. Failure of a large power transformer not only results in the loss of very expensive equipment, but it can cause significant guarantied damage as well. Replacement of that transformer can take up to a year if the failure is not disastrous and can result in tremendous revenue losses and fines. A Power Transformer in operation is subjected to various stresses like thermal stress and electrical stress, resulting in liberation of gases from the hydrocarbon mineral oil which is used as insulant and coolant. Dissolved Gas Analysis is a technique used to assess incipient faults of the transformer by analyzing specific dissolved gas concentrations arising from the deterioration of the transformer. DGA is used not only as a diagnostic tool but also to track apparatus failure. In this research work the dissolved gas values measured in PPM for a 230KV/110KV Power Transformer which are obtained from Electricity Board are used as references to the developed Neural Network. The Neural Network was trained and the gas concentration values for forthcoming years were predicted. Using the interpretation result of Key gas method, Rogers method and IS: 10593 method, the predicted gas concentration values compared and the fault of the Power Transformer were predicted. The trained Neural Network shows the good performance for the prediction of fault in a 230KV / 110KV Power Transformer.

Fault prediction based on dissolved gas concentration from insulating oil in power transformer using Neural Network

This proposal proposes a DC/DC Buck Boost converter which has been used as a smooth starter for a DC Permanent Magnet Motor. In the existing system the DC/DC Buck Converter is used which provide the output less than the input Signal. Using buck converter it is difficult to increase the value of the input signal. Hence DC/DC Buck- Boost Converter used from which it is possible to get both the increased and decreased output from the given input. Previously pulse width modulation signals with respective to motor voltage is used. However they produce variations in the voltage and current of the motor. The above problem is overcome by using DC/DC Power converter. The proposed system with reduction in size, reduced ripples and increase in speed makes the system to operate at both low and high power applications. The proposed system results in higher efficiency, reduces the ripple content and the stress. The results are validated through MATLAB/Simulink and real time implementation.

/pdf/design-and-implementation-of-a-microcontroller-based-buck-2bg2ehthlz.pdf

K. Iyswarya Annapoorani

Papers

Multi-Port Current Source Inverter for Smart Microgrid Applications: A Cyber Physical Paradigm

A Review on Back-to-Back Converters in Permanent Magnet Synchronous Generator based Wind Energy Conversion System

Fault prediction based on dissolved gas concentration from insulating oil in power transformer using Neural Network

Design and implementation of a microcontroller based buck boost converter as a smooth starter for permanent magnet motor

Fuzzy logic-based integral controller for load frequency control in an isolated micro-grid with superconducting magnetic energy storage unit