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The solar photovoltaic (PV) system is one of the outstanding, clean and green energy options available for electrical power generation. The varying meteorological operating conditions impose various challenges in extracting maximum available power from the solar PV system. The drawbacks of conventional and evolutionary algorithms-based maximum power point tracking (MPPT) approaches are its inability to extract maximum power during partial shading conditions and quickly changing irradiations. Hence, the purpose of this paper is to propose a modified elephant herding optimization (MEHO) based MPPT approach to track global maximum power point (GMPP) proficiently during dynamic and steady state operations within less time.

A MEHO-based MPPT approach is proposed in this paper by incorporating Gaussian mutation (GM) in the original elephant herding optimization (EHO) to enhance the optimizing capability of determining the optimal value of DC–DC converter’s duty cycle (D) to operate at GMPP.

The effectiveness of the proposed system is compared with EHO based MPPT, Firefly Algorithm (FA) MPPT and particle swarm optimization (PSO) MPPT during uniform irradiation condition (UIC) and partial shading situation (PSS) using simulation results. An experimental setup has been designed and implemented. Simulation results obtained are validated through experimental results which prove the viability of the proposed technique for an efficient green energy solution.

With the proposed MEHO MPPT, it has been noted that the settling period is lowered by 3.1 times in comparison of FA MPPT, 1.86 times when compared to PSO based MPPT and 1.29 times when compared to EHO based MPPT with augmented efficiency of 99.27%.

The purpose of this paper is energy consumption and security. To extend the sensor’s life span, saving the energy in a sensor is important. In this paper, biosensors are implanted or suited on the human body, and then, transposition has been applied for biosensors for reducing the sensor distance from the sink node. After transposition path loss has been calculated, security is maintained and also compared the results with the existing strategies.

Nowadays, one of the most emergent technologies is wireless body area network (WBAN), which represents to improve the quality of life and also allow for monitoring the remote patient and other health-care applications. Traffic routing plays a main role together with the relay nodes, which is used to collect the biosensor’s information and send it towards the sink.

To calculate the distance and observe the position, Euclidean distance technique is used. Path loss is the main parameter, which is needed to reduce for making better data transmission and to make the network stability. Routing protocols can be designed, with the help of proposed values of sensors locations in the human body, which gives good stability of network and lifetime. It helps to achieve as the less deplete energy.

This scheme is compared with the two existing schemes and shows the result in terms of parameter path loss. Moreover, this paper evaluated a new method for improving the security in WBAN. The main goal of this research is to find the optimal sensor location on the body and select the biosensor positions where they can get less energy while transmitting the data to the sink node, increasing the life span in biosensors, decreasing memory space, giving security, controlling the packet complexity and buffer overflow and also fixing the damages in the existing system.

The lack of studies about the relevance of disaster awareness factors and disaster evacuation as a part of disaster responses especially for fire cases in an academic environment in Indonesia has triggered this study to explore the disaster awareness factors and evacuation experiment without emergency alarm for case study students in the classroom. The relevance of disaster awareness factors in transforming into practical action and decision in a disaster evacuation need to be examined to study the relevance of both phases in disaster.

This research conducted a quantitative approach by studying questionnaires from 162 respondents collectively divided into five groups to examine the student disaster awareness factors randomly from those groups. The qualitative approach was implemented through the evacuation experiments that were conducted twice to analyze the disaster evacuation performance. The analysis for the relevance is conducted by comparing the result of the questionnaire study and the evacuation experiment.

According to the questionnaire study, generally, the students are highly confident with their hazard knowledge in disaster awareness except that half of them are doubtful about appropriate steps in a disaster. The experiment without explosive sound showed that they have slower responses in the critical moment of evacuation. The response in the experiments showed relevance with several disaster awareness factors

This study has explored the relevance of disaster awareness factors with disaster response in a campus building. In the part of reducing risk during fire disaster, this research shows the importance of social interaction and hazard knowledge during the disaster.

The improvement of disaster evacuation procedures and training in a campus building is mandatory to reduce disaster risk based on the relevance of disaster awareness factors and disaster response in this study.

This study measures the relevance of disaster awareness factors performance of the students by comparing it to their actions and decisions in an experimental setting of fire building. The disaster awareness factor performance was measured by a questionnaire survey while the experiments were deployed to observe the performance of their actions and decisions during evacuation as part of the disaster response phase.

The incidence of disability is increasing globally over the past decades. Despite the increased proportion of disabled individuals, established fire emergency evacuation procedures for disabled in high-rise buildings are lacking attention. Hence, this paper aims to focus on investigating fire emergency evacuation procedures for differently-abled people in high-rise buildings.

To address the gap, the case study strategy under the qualitative research approach was deployed by focussing 10 high-rise buildings. Data collected through semi-structured interviews and document reviews were analysed using content analysis.

The study findings revealed that even though a fire disaster is a major area to be considered, there is a noticeable gap in legal requirements related to differently-abled fire evacuation in Sri Lanka compared to the global context. Moreover, it was identified that importance given to differently enabled fire evacuations procedures varied based on the type of high-rise facilities in which hospitals and hotels provided more importance compared to office buildings, apartments and shopping complexes. Further, the study has highlighted the main gaps in the evacuation procedures and improvements required. Lack of imposed regulations for disabled evacuation was identified as a major barrier hindering the development of effective fire evacuation procedures for disabled, which creates a cascading effect. Further, the consideration given to legal, organisational, individual and technological factors would assist in straightening the identified issues.

This research provides a clear insight into the necessity of focussing at disabled individuals when developing fire emergency procedures. Most importantly, this study had exposed the current gaps in fire emergency evacuation procedures for the disabled community. Understanding these gaps is of high value for industry practitioners to ensure disabled safety during a fire emergency.

A switching depth controller based on a variable buoyancy system (VBS) is proposed to improve the performance of small autonomous underwater vehicles (AUVs). First, the requirements of VBS for small AUVs are analyzed. Second, a modular VBS with high extensibility and easy integration is proposed based on the concepts of generality and interchangeability. Subsequently, a depth-switching controller is proposed based on the modular VBS, which combines the best features of the linear active disturbance rejection controller and the nonlinear active disturbance rejection controller.

The controller design and endurance of tiny AUVs are challenging because of their low environmental adaptation, limited energy resources and nonlinear dynamics. Traditional and single linear controllers cannot solve these problems efficiently. Although the VBS can improve the endurance of AUVs, the current VBS is not extensible for small AUVs in terms of the differences in individuals and operating environments.

The switching controller’s performance was examined using simulation with water flow and external disturbances, and the controller’s performance was compared in pool experiments. The results show that switching controllers have greater effectiveness, disturbance rejection capability and robustness even in the face of various disturbances.

A high degree of standardization and integration of VBS significantly enhances the performance of small AUVs. This will help expand the market for small AUV applications.

This solution improves the extensibility of the VBS, making it easier to integrate into different models of small AUVs. The device enhances the endurance and maneuverability of the small AUVs by adjusting buoyancy and center of gravity for low-power hovering and pitch angle control.

The development of urban underground complexes (UUCs) has great positive significance for improving urban safety. Therefore, it is necessary to identify the key factors of the people's behavior of evacuation route selection (BERS) for fire emergencies and UUCs’ development. This study aims to find out the factors affecting people's BERS in the evacuation process of UUCs.

This study aims to find out the factors affecting people's BERS in the evacuation process of UUCs. To achieve this goal, the authors conducted a field experiment in F City. Furthermore, the people's BERS are obtained by using a structural equation model and compared with the field test results.

The authors found that the key factors for people's BERS are lighting conditions, route distance, flow direction guidance and indication. The results of this study contribute to the safety field by providing key factors for fire emergencies. It can also be used to improve fire safety management, evacuation strategies and assist in the development of intelligent evacuation systems.

The results of this study contribute to the safety field by providing key factors for fire emergencies. It can also be used to improve fire safety management, evacuation strategies and assist in the development of intelligent evacuation systems.