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The purpose of this paper is to construct an event-triggered finite-time fault-tolerant formation tracking controller, which can achieve a time-varying formation control for multiple unmanned aerial vehicles (UAVs) during actuator failures and external perturbations.

First, this study developed the formation tracking protocol for each follower using UAV formation members, defining the tracking inaccuracy of the UAV followers’ location. Subsequently, this study designed the multilayer event-triggered controller based on the backstepping method framework within finite time. Then, considering the actuator failures, and added self-adaptive thought for fault-tolerant control within finite time, the event-triggered closed-loop system is subsequently shown to be a finite-time stable system. Furthermore, the Zeno behavior is analyzed to prevent infinite triggering instances within a finite time. Finally, simulations are conducted with external disturbances and actuator failure conditions to demonstrate formation tracking controller performance.

It achieves improved performance in the presence of external disturbances and system failures. Combining limited-time adaptive control and event triggering improves system stability, increase robustness to disturbances and calculation efficiency. In addition, the designed formation tracking controller can effectively control the time-varying formation of the leader and followers to complete the task, and by adding a fixed-time observer, it can effectively compensate for external disturbances and improve formation control accuracy.

A formation-following controller is designed, which can handle both external disturbances and internal actuator failures during formation flight, and the proposed method can be applied to a variety of formation control scenarios and does not rely on a specific type of UAV or communication network.

The purpose of this study is to analyse numerous aspects affecting residential property price in Malaysia against macroeconomics issues such as gross domestic product (GDP), exchange rate, unemployment and wage.

The hedonic pricing model has been adopted as econometric model for this research to investigate the relationship between residential property price against macroeconomics indicator. The data for residential property price and macroeconomic variables were collected from 1991 to 2019. Multiple linear regression had been adopted to find the relationship between the dependent and independent variables.

The result shows that the GDP has a significant positive impact on residential property price, while exchange rate has no significant impact although it was positive. In addition, the unemployment rate has a significant impact on the residential property price and has a negative relationship. Similar to the wage that shows the negative relationship with residential property prices. Moreover, during the pandemic COVID-19 in Malaysia, this research shows a more transparent view of the relationship between residential property price and the macroeconomic issues of GDP, exchange rate, unemployment and wage.

The findings of this research found that macroeconomics issue cannot be eliminated due to Malaysia is a developing country, and there will always be an issue that will happen, but the issues can be reduced to maximise the advantages, e.g. during COVID-19, the solution to fight against COVID-19 were crucial and weaken the macroeconomics issues.

Today social media capabilities have enabled businesses and enterprises to more collaboration, engagement and co-creation with their customers. So the current paper expands on this notion. The aim of this study is a bibliometric analysis to examine the trends of publications in the field of co-creation based on social media.

To data collection of quantitative analysis, Scopus database was selected and the collected data were analyzed using Bibliometrix-package. The Web of Science also was selected to retrieve highly cited and hot papers for qualitative part of analysis besides top 10 Scopus highest citation per year documents on June 6, 2020.

The results indicate insights into research trends pertaining to social media-based co-creation, as follows: starting jump to the publications occurred in this researches from the year 2008 and the growth trend is progressing in recent years; the stressful points are “co-design,” “co-creation” and “value co-creation” and concepts such as “open innovation,” “co-innovation” and “co-new product design” are new topics that guide future direction; the USA and UK are leaders in number of multiple and single publications; the most active and top journals that are better suited to achieving a high citation rate per year for a related paper were introduced. In addition, the top documents and highly cited papers were qualitatively analyzed on the basis of times cited per year.

The current study is not free of limitations. The database was limited to only Scopus. So the patterns and trends generated in the study may not be generalized to all social media-based co-creation research. Of course, the authors did not intend to ignore other contributions. It is mainly because of the number of documents retrieved from Scopus database and the coverage, Scopus was selected. Moreover, other types of research techniques such as correspondence analysis can be incorporated to generate additional meaningful insight.

In this time of social media and user-generated content portals, co-creation through social media has become quite popular. So the main innovation of this study is providing a visual presentation of the trends and patterns in the evaluation of social media-based co-creation from the first document about the research area published till 2020. The results of this paper can shed light on the factors that strengthen the contribution of studies in a research area. Generally, the bibliometric items the authors analyzed essentially show the entire field picture and guide researchers toward understanding future trends to produce impactful studies.

The purpose of this paper is to create optimally located Facilitation Centers on this tourist circuit, evaluated through network analysis, thus creating an effective linkage between tourism and economic activities of the craftsmen who are the custodians of the cultural heritage of Puri.

The craft villages lying in and around this tourist circuit are surveyed to establish socio-economic condition of artisans, significance of the craft and spatial distribution of craft villages and the willingness of artisans to travel closer to the transport spine. Network analysis is used to assess the suitability of Facilitation Center location using travel time and distance as parameters. Finally, the sustainability of the Facilitation Centers is evaluated using a cost-benefit analysis (CBA).

The Facilitation Centers can be spatially developed at the strategic locations to expand tourist market. This will help in leveraging the economic benefits of tourism to a marginalized rural artisan community by creating a sustainable model.

The focus on festival can help to protect local cultural traditions, develop tourism and promote the economic, social and cultural developments of the destination. Dispersal strategies adopted aim to increase visitors' satisfaction with the product and thus entice them to stay longer in the destination.

The purpose of this study is to provide the enhancement of power quality of a high power-rated voltage source inverter driven induction motor with a three-phase, three-level neutral point clamped converter placed at the front end, while a passive power filter is connected in shunt with it. The improvement in power quality can be achieved by reducing the total harmonic distortion in source current. The controllers were designed for the linearization of the high-power induction motor drive. A control method is presented for the regulation of the common DC-link voltage.

The induction motor is modeled using its dynamic equations, and a decoupling controller is designed to linearize the nonlinear dynamics of the drive through feedback. The common DC-link voltage of the proposed front-end connected converter is monitored and controlled through a control method which feeds the pulse width modulated inverter that drives the induction motor. A passive power filter is designed to meet the reactive power requirement of the system in addition to improve the power quality.

Simulations were carried out for the proposed topology of the drive mechanism, and the outcomes were analyzed by a comparative analysis of the drive system both in the presence of the passive filter as well as in the absence of the filter. The total harmonic distortion is found to be reduced enough to meet the standards with the designed filter, and the reactive power is also compensated considerably. The input power factor at the supply side is maintained almost to unity, and the DC-link voltage of the proposed circuit topology is maintained at the desired level. The overall performance of the drive system was found to be useful and economical.

A new topology of a front-end connected three-level neutral point clamped converter to a high power-rated induction motor drive is proposed. The drive is fed by a pulse width modulated inverter with a common DC-link with the front end connected converter. A passive filter is designed with respect to the reactive power requirement of the system and connected in shunt to the converter at the supply side. Control schemes are designed and used for the drive system and also for the regulation of the common DC-link voltage of the proposed front end connected converter.