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Autonomous flight of unmanned aerial vehicles (UAVs) in global position system (GPS)-denied environments has become an increasing research hotspot. This paper aims to realize the indoor fixed-point hovering control and autonomous flight for UAVs based on visual inertial simultaneous localization and mapping (SLAM) and sensor fusion algorithm based on extended Kalman filter.

The fundamental of the proposed method is using visual inertial SLAM to estimate the position information of the UAV and position-speed double-loop controller to control the UAV. The motion and observation models of the UAV and the fusion algorithm are given. Finally, experiments are performed to test the proposed algorithms.

A position-speed double-loop controller is proposed, by fusing the position information obtained by visual inertial SLAM with the data of airborne sensors. The experiment results of the indoor fixed-points hovering show that UAV flight control can be realized based on visual inertial SLAM in the absence of GPS.

A position-speed double-loop controller for UAV is designed and tested, which provides a more stable position estimation and enabled UAV to fly autonomously and hover in GPS-denied environment.

This chapter examines the explosion in International Humanitarian Law between the US Civil War and World War I. The primary foci are the Hague Conventions on land warfare and the Geneva Conventions for the sick and wounded. This body of treaties is the foundation of IHL and the modern laws of war. Most of central issues in the international laws of war emerge in this period.

The geopolitical significance of the Mediterranean Sea transcends regional security and energy supply, profoundly impacting global security dynamics. Daily headlines underscore the plight of migrants from the Middle East and North Africa crossing the Mediterranean, exacerbating humanitarian crises and European identity challenges. Environmental concerns are further heightened by the abundance of global ports facilitating oil and goods transportation, alongside the staggering number of tourists flocking to the Mediterranean coast annually. This chapter serves as a gateway to the book, exploring the concept of “geopolitics” and delineating its characteristics. It specifically delves into the political economy of the Eastern Mediterranean and the geopolitical obstacles to energy security in the region. The chapter strategically selects four primary issues to dissect the region’s conflict complexity: the Syrian crisis, the Israeli–Palestinian conflict, the unresolved Cyprus dispute, and the Lebanon–Israel conflict over water border demarcation.

There does not exist any precise definition of ‘development’. In view of the indispensability of an interpretation of this concept a degree of speculation seems to exist in a development process. This is the reason this chapter has been included in this work. No scholar has precisely defined ‘development’ and ‘developing’ countries. It is believed that indigenous people know best what would be most suitable for them for development of their country. However, any discussion of these topics becomes incomplete, controversial, etc. in the absence of any precise definition. This chapter is no exception to this although an attempt has been made to outline development.

The main aim of this article is to broaden the notion of strategic intent in public relations. It also develops an understanding of the social value of what can be defined as the first modern health communication campaign in Europe based on strategic intents and the development of modernity.

The study is based on both historical research and empirical material from the Norwegian tuberculosis campaign from 1889 up to 1913, when Norwegian women achieved suffrage. The campaign is analysed in the framework of modernity and social theory. The literature on lobbying and social movements is also used to develop a theoretical framework for the notion of strategic intent.

The study shows that strategic intent can be divided into two layers: (1) the implicit strategic intent is the real purpose behind the communication efforts, whereas (2) the explicit intent is found directly in the communication efforts. The explicit intent may be presented as a solution for the good of society at the right political moment, giving an organisation the possibility to mobilise for long-term social changes, in which could be the implicit intent.

The distinction between explicit and implicit strategic intent broadens our understanding on how to make long-term social changes as well as how social and political changes occur in modern societies. The article also gives a historical account of what is here defined as the first modern health communication campaign in Europe and its social value.

This study aims to assess the spread of environmental literacy graduation requirements at public universities in the USA, and to highlight factors that mediate the adoption of this curriculum innovation.

The author analyzed the undergraduate general education curriculum requirements at all 549 public BA-granting higher education institutions in the USA between 2020 and 2022.

The study found that only 27 US public universities out of 540 have an environmental literacy graduation requirement, which represents 5% of universities and is substantially lower than previous estimates.

First, this study provides a more complete, more reliable and more current assessment of the graduation requirement’s presence at US tertiary institutions, and shows the number of universities that have implemented this innovation is lower than was estimated a decade ago. Second, it draws from the scholarship on the infusion of sustainability into the university curriculum to provide a comprehensive discussion of factors that mediate the pursuit and implementation of the graduation requirement. As well, it identifies factors that played a key role in one pertinent case.

To ensure the stability of the flying wing layout unmanned aerial vehicle (UAV) during flight, this paper uses the radial basis function neural network model to analyse the stability of the aforementioned aircraft.

This paper uses a linear sliding mode control algorithm to analyse the stability of the UAV's attitude in a level flight state. In addition, a wind-resistant control algorithm based on the estimation of wind disturbance with a radial basis function neural network is proposed. Through the modelling of the flying wing layout UAV, the stability characteristics of a sample UAV are analysed based on the simulation data. The stability characteristics of the sample UAV are analysed based on the simulation data.

The simulation results indicate that the UAV with a flying wing layout has a short fuselage, no tail with a horizontal stabilising surface and the aerodynamic focus of the fuselage and the centre of gravity is nearby, which is indicative of longitudinal static instability. In addition, the absence of a drogue tail and the reliance on ailerons and a swept-back angle for stability result in a lack of stability in the transverse direction, whereas the presence of stability in the transverse direction is observed.

The analysis of the stability characteristics of the sample aircraft provides the foundation for the subsequent establishment of the control model for the flying wing layout UAV.

Autonomous underwater vehicle (AUV) is widely used in resource prospection and underwater detection due to its excellent performance. This study considers input saturation, nonlinear model uncertainties and external ocean current disturbances. The containment errors can be limited to a small neighborhood of zero in finite time by employing control strategy. The control strategy can keep errors within a certain range between the trajectory followed by AUVs and their intended targets. This can mitigate the issues of collisions and disruptions in communication which may arise from AUVs being in close proximity or excessively distant from each other.

The tracking errors are constrained. Based on the directed communication topology, a cooperative formation control algorithm for multi-AUV systems with constrained errors is designed. By using the saturation function, state observers are designed to estimate the AUV’s velocity in six degrees of freedom. A new virtual control algorithm is designed through combining backstepping technique and the tan-type barrier Lyapunov function. Neural networks are used to estimate and compensate for the nonlinear model uncertainties and external ocean current disturbances. A neural network adaptive law is designed.

The containment errors can be limited to a small neighborhood of zero in finite time so that follower AUVs can arrive at the convex hull consisting of leader AUVs within finite time. The validity of the results is indicated by simulations.

The state observers are designed to approximate the speed of the AUV and improve the accuracy of the control method. The anti-saturation function and neural network adaptive law are designed to deal with input saturation and general disturbances, respectively. It can ensure the safety and reliability of the multiple AUV systems.