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Currently, path planning for an unmanned ship is usually performed in a single domain on the water surface or underwater, and little research exists on path planning for a three-dimensional (3D) environment where the ship crosses the water’s surface and underwater. The existing 3D path planning research still has improvement possibilities in reserving a safe distance between the ship and the obstacles. In this paper, path planning for a submersible surface ship (SSS) in a 3D environment is carried out based on an ant colony algorithm. Path safety is enhanced by introducing constraints related to boat width to keep the path at a safe distance from obstacles. By extracting key points, the length of the path is further reduced. The algorithmic procedure with the objective of the shortest time was obtained by assigning different speeds to the SSS sailing at the same depth and across different depths. The rationality and superiority of the method given in this paper are verified in several sets of simulations and comparative experiments. The paper concludes that path selection is more inclined to choose the water surface as the depth of the obstacles increases and the density of the obstacles decreases. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate how commonly used 2D digital layouts can be transformed into 3-dimensional dashboards with the effect of reducing cognitive load. To this end, we compared user performance metrics, pupil dilation data as well as subject-reported qualitative measures in a Web 2.0-based 2D scenario and two different versions of a desktop 3D virtual reality scenario. All three scenarios focused on a use case involving the most prevalent 2D digital formats and designs encountered in digital education, making use of e.g. textual information (PDF files, PPT files), images and videos. Based on the assumption that cognitive load differences can be validated based on pupillometry measurements, we showed that it is possible to develop 3D virtual reality scenarios where users experience less cognitive load while achieving the same performance metrics as in commonly used 2D environments. At the same time, our experiment also showed that such improvements do not come automatically; instead, 3D workflows that require less locomotion – even at the expense of increased camera rotations – seem to result in more effective cognitive load reduction.

Recent advances in Deep Learning (DL) and ReinforcementLearning (RL) make it possible to train neural network agentswith raw, first-person visual perception to execute language-like instructions in 3D simulated worlds. Here, we inves-tigate the application of such deep RL agents as cognitivemodels, specifically as models of infant word learning. Wefirst develop a simple neural network-based language learningagent, trained via policy-gradient methods, which can inter-pret single-word instructions in a simulated 3D world. Tak-ing inspiration from experimental paradigms in developmentalpsychology, we run various controlled simulations with the ar-tificial agent, exploring the conditions in which established hu-man biases and learning effects emerge, and propose a novelmethod for visualising and interpreting semantic representa-tions in the agent. The results highlight the potential util-ity, and some limitations, of applying state-of-the-art learningagents and simulated environments to model human cognition.

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Deploying wireless sensor networks (WSNs) in real-world applications is still a challenging problem. Indeed, the number, locations, and orientations of directional sensors determine the topology of the WSN, which will further influence its overall cost and performance. Existing works have assumed simple sensor behavior and/or ideal environmental factors; thus, often they do not produce practical results. On the contrary, in this paper, we revisit the 3D WSNs deployment problem while considering realistic assumptions regarding the modeling of both the sensors and the environment. More precisely, we propose a Bresenham line-of-sight based realistic coverage model for 3D environments. This latter is used to re-formalize the 3D WSNs deployment problem while considering a realistic spatial model of the environment. The problem is then solved using a multi-objective genetic algorithm endowed with new adaptive and guided genetic operators. Moreover, we enhance the performance of the proposed approach by introducing two optimization techniques, namely: search space reduction and sampling-based evaluation. We show the effectiveness and efficiency of the proposed approach through extensive simulations. [ABSTRACT FROM AUTHOR]

Aim: Understanding the mechanisms that allow the coexistence of species is key to preserve full ecosystem functioning. In dynamic environments, the study of ecological niches faces the complexity associated to the three dimensionality of the habitat and requires information that reflects such heterogeneity. Within this context, this study intends to identify the segregation mechanisms behind the co‐occurrence of five phylogenetically related pelagic birds by applying a functional perspective based on seabirds' vertical ranges and prey availability features such as depth and body size. Location: Bay of Biscay. Methods: Based on the hypothesis that niche differentiation may occur in any of the three dimensions of the marine environment, we (a) identified the biologically meaningful vertical range affecting seabird species, (b) modelled their environmental and trophic niches, (c) estimated an environmental and trophic overlap index for each pairwise species, and (d) developed a conceptual framework with the most plausible segregation hypotheses. Results: The application of the conceptual framework revealed that in this particular area, pelagic birds coexist through environmental and trophic niche partitioning and potentially through vertical segregation, based on the different biologically meaningful vertical ranges we identified for each species. Indeed, some species responded to prey and oceanographic conditions on the surface (10 m), while others responded to the conditions on deeper waters (above the depth of maximum temperature gradient). These different responses could be interpreted as an additional mechanism to reduce competition, although seabirds diving records would be needed to contrast this hypothesis. Main conclusions: Niche differentiation was found to be primarily driven by trophic and environmental niche partitioning, although species were also influenced by conditions on the vertical dimension. Considering all the dimensions of the niche is essential to fully understand how diving seabirds coexist in dynamic systems and provides insights on species' 3D niches that may help advance into their management. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate how commonly used 2D digital layouts can be transformed into 3-dimensional dashboards with the effect of reducing cognitive load. To this end, we compared user performance metrics, pupil dilation data as well as subject-reported qualitative measures in a Web 2.0-based 2D scenario and two different versions of a desktop 3D virtual reality scenario. All three scenarios focused on a use case involving the most prevalent 2D digital formats and designs encountered in digital education, making use of e.g. textual information (PDF files, PPT files), images and videos. Based on the assumption that cognitive load differences can be validated based on pupillometry measurements, we showed that it is possible to develop 3D virtual reality scenarios where users experience less cognitive load while achieving the same performance metrics as in commonly used 2D environments. At the same time, our experiment also showed that such improvements do not come automatically; instead, 3D workflows that require less locomotion - even at the expense of increased camera rotations - seem to result in more effective cognitive load reduction., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Author(s).)

Professional landscape architecture organizations have requested training from educational institutions based on new skills and methodologies in the curriculum development of students. Landscape architects need to visualize and evaluate the spatial relationships between the different components of the landscape using two-dimensional (2D) or three-dimensional (3D) maps and geospatial information, for which spatial orientation skills are necessary. The data from six workshops conducted throughout the 2010–2020 period, in which 560 second-year engineering students participated using different strategies and technical tools for spatial orientation skills’ development, were collected in a unique study. Factors such as the technology used, the gaming environment, the type of task, the 2D/3D environment, and the virtual environment were considered. The Perspective-Taking Spatial Orientation Test was the measurement tool used. The results show that mapping tasks are more efficient than route-based tasks. Strategies using 2D and a 2D/3D combination are more effective than those with only 3D. First-person perspective gaming environments are also a valid alternative. The technologies applied in this study are easy to use and free, and a measurement tool is provided. This facilitates an interdisciplinary approach between landscape architecture education and professional practice since these workshops could also be easily carried out by professional bodies for landscape planning and management.

3D technology can be a valid support to cultural heritage not only for visual presentation and documentation, but also for communication and educational purposes. In this paper, we will discuss the potential of 3D virtual environments as effective learning contexts for Cultural Heritage. This encompasses various disciplines such as history, art, and languages, and includes both tangible and intangible content like myths, beliefs and social values. We will analyse virtual and augmented reality and innovative interfaces, highlighting their affordances for successfully triggering learning experiences. A number of digital environments and serious games will be also analysed with respect to their potential for supporting immersion, presence and motivation. In the literature, these factors are considered key in raising learner interest, making 3D worlds a direct and engaging setting for informal learning in Cultural Heritage.

This research explores the suitability and effectiveness of two relatively new types of input device for navigating 3D virtual environments. These are infrared motion detection, like the Leap Motion tracker, and electromyographic gesture recognition, like theMyo Armband. Despite the introduction of a variety of new input devices intended to provide a more natural interaction experience, navigation within 3D virtual environments is still normally done on more traditional control devices such as game controllers or the keyboard-mouse combination. This study investigates the potential of new devices to support navigation in 3D environments through an experiment conducted with 27 participants using three different types of input devices to play a ball-balancing maze-like game. The input devices tested are a standard game controller, a Leap Motion tracker for infrared motion detection, and the Myo Armband for electromyographic gesture recognition. Results demonstrated the real potential of both types of device to support navigation interaction within 3D environments. [ABSTRACT FROM AUTHOR]

Due to the perceptual characteristics of the head, vibrotactile Head-mounted Displays are built with low actuator density. Therefore, vibrotactile guidance is mostly assessed by pointing towards objects in the azimuthal plane. When it comes to multisensory interaction in 3D environments, it is also important to convey information about objects in the elevation plane. In this paper, we design and assess a haptic guidance technique for 3D environments. First, we explore the modulation of vibration frequency to indicate the position of objects in the elevation plane. Then, we assessed a vibrotactile HMD made to render the position of objects in a 3D space around the subject by varying both stimulus loci and vibration frequency. Results have shown that frequencies modulated with a quadratic growth function allowed a more accurate, precise, and faster target localization in an active head pointing task. The technique presented high usability and a strong learning effect for a haptic search across different scenarios in an immersive VR setup. [ABSTRACT FROM PUBLISHER]

ABSTRACT A pedagogical model for teaching wireless sensor network courses to Libyan students is presented in this paper, using 3D virtual classes and utilizing the collaborative learning technique by mixing students with different languages and different learning styles. We describe how a wireless sensor network simulator was integrated into a 3D environment for use in multilingual teaching environment. This learning model was based on simulation tool eWISENS. The system enables students from different countries to collaborate and work together, and creating an international environment helps Libyan students to overcome the language barrier and organize virtual sessions with colleagues all over the world. © 2017 Wiley Periodicals, Inc. Comput Appl Eng Educ 25:200-213, 2017; View this article online at ; DOI [ABSTRACT FROM AUTHOR]

Abstract Virtual worlds, shared graphical spaces on the Internet, are an exciting new medium of human presence for the twenty-first century. This article explores the origins, evolution, and future of the virtual world medium from their humble beginnings in multi-player games to their use in education, business, science, and engineering. Its focus will be on the development of social virtual worlds including environments such as Habitat, Active Worlds, and Second Life.

Route planning is a key technology for an unmanned aerial vehicle (UAV) to fly reliably and safely in the presence of a threat environment. Existing route planning methods are mainly based on the simulation scene, whereas approaches based on the virtual globe platform have rarely been reported. In this paper, a new planning space for the virtual globe and the planner is proposed and a common threat model is constructed for threats including a no-fly zone, hazardous weather, radar coverage area, missile killing zone and dynamic threats. Additionally, an improved ant colony optimization (ACO) algorithm is developed to enhance route planning efficiency and terrain masking ability. Our route planning methods are optimized on the virtual globe platform for practicability. A route planning system and six types of planners were developed and implemented on the virtual globe platform. Finally, our evaluation results demonstrate that our optimum planner has better performance in terms of fuel consumption, terrain masking, and risk avoidance. Experiments also demonstrate that the method and system described in this paper can be used to perform global route planning and mission operations. [ABSTRACT FROM AUTHOR]

The acquisition of teacher digital competence is a key aspect in the initial training of teachers. However, most existing evaluation instruments do not provide sufficient evidence of this teaching competence. In this study, we describe the design and development process of a three-dimensional (3D) virtual environment for evaluating the teacher digital competence of future teachers, through a performance-based, collaborative and contextual evaluation. This environment, named ETeach3D, has been constructed using the educational design research approach. It is based on successive iterative cycles and is in accordance with the criteria of usefulness, validity, and effectiveness. In addition to the research team responsible for the project, participating in this study were 187 Spanish undergraduate students of Education and 22 experts in the field of educational technology. Results show that these environments, in addition to other characteristics, should (a) function smoothly and have simple interfaces, realistic scenes, and interactive activities and (b) follow a systematic evaluation procedure that integrates several strategies and levels of complexity. This research helps to improve the initial training of preservice teachers and contributes to the growing number of educational design research studies that focus in the field of evaluation of the curriculum domain. [ABSTRACT FROM AUTHOR]

Spatial training can be durable and transferable if the training involves cognitive process-based tasks. The current study explored different spatial training methods and investigated the sequences of process-based mental simulation that was facilitated by various structures of external spatial representation, 3D technology, spatial cues, and/or technical languages. A total of 115 Columbia University's students were conducted through three experiments using a between-subjects design to examine the effects of spatial training methods on spatial ability performance. The conditions for training environments included 3D-virtual and 3D-physical interactions with abstract ( nonsense- geometric) and concrete ( everyday- object) contents. Overall, learners in the treatment conditions improved in their spatial skills significantly more than those in the control conditions. Particularly, 3D-direct-manipulation conditions in the third experiment added promising results about the specific sequences during spatial thinking formation processes. [ABSTRACT FROM AUTHOR]

We discuss the evolution and state-of-the-art of the use of Building Information Modelling (BIM) in the field of culture heritage documentation. BIM is a hot theme involving different characteristics including principles, technology, even privacy rights for the cultural heritage objects. Modern documentation needs identified the potential of BIM in the recent years. Many architects, archaeologists, conservationists, engineers regard BIM as a disruptive force, changing the way professionals can document and manage a cultural heritage structure. The latest years, there are many developments in the BIM field while the developed technology and methods challenged the cultural heritage community in the documentation framework. In this review article, following a brief historic background for the BIM, we review the recent developments focusing in the cultural heritage documentation perspective. [ABSTRACT FROM AUTHOR]

Virtual worlds, shared graphical spaces on the Internet, are an exciting new medium of human presence for the twenty-first century. This article explores the origins, evolution, and future of the virtual world medium from their humble beginnings in multi-player games to their use in education, business, science, and engineering. Its focus will be on the development of social virtual worlds including environments such as Habitat, Active Worlds, and Second Life.

Abstract: A large body of HCI research focuses on devices and techniques to interact with applications in more natural ways, such as gestures or direct pointing with fingers or hands. In particular, recent years have seen a growing interest in laser pointer-style (LPS) interaction, which allows users to point directly at the screen from a distance through a device handled like a common laser pointer. Several LPS techniques have been evaluated in the literature, usually focusing on users'' performance and subjective ratings, but not on the effects of these techniques on the musculoskeletal system. One cannot rule out that “natural” interaction techniques, although found attractive by users, require movements that might increase likelihood of musculoskeletal disorders (MSDs) with respect to traditional keyboard and mouse. Our study investigates the physiological effects of a LPS interaction technique (based on the Wii Remote) compared to a mouse and keyboard setup, used in a sitting and a standing posture. The task (object arrangement) is representative of user actions repeatedly carried out with 3D applications. The obtained results show that the LPS interaction caused more muscle exertion than mouse and keyboard. Posture played also a significant role. The results highlight the importance of extending current studies of novel interaction techniques with thorough electromyographic (EMG) analyses. [Copyright &y& Elsevier]

The graph-search algorithms developed between 60s and 80s were widely used in many fields, from robotics to video games. The A* algorithm shall be mentioned between some of the most important solutions explicitly oriented to motion-robotics, improving the logic of graph search with heuristic principles inside the loop. Nevertheless, one of the most important drawbacks of the A* algorithm resides in the heading constraints connected with the grid characteristics. Different solutions were developed in the last years to cope with this problem, based on post-processing algorithms or on improvements of the graph-search algorithm itself. A very important one is Theta* that refines the graph search allowing to obtain paths with 'any' heading. In the last two years, the Flight Mechanics Research Group of Politecnico di Torino studied and implemented different path planning algorithms. A Matlab based planning tool was developed, collecting four separate approaches: geometric predefined trajectories, manual waypoint definition, automatic waypoint distribution (i.e. optimizing camera payload capabilities) and a comprehensive A*-based algorithm used to generate paths, minimizing risk of collision with orographic obstacles. The tool named PCube exploits Digital Elevation Maps (DEMs) to assess the risk maps and it can be used to generate waypoint sequences for UAVs autopilots. In order to improve the A*-based algorithm, the solution is extended to tri-dimensional environments implementing a more effective graph search (based on Theta*). In this paper the application of basic Theta* to tri-dimensional path planning will be presented. Particularly, the algorithm is applied to orographic obstacles and in urban environments, to evaluate the solution for different kinds of obstacles. Finally, a comparison with the A* algorithm will be introduced as a metric of the algorithm performances. [ABSTRACT FROM AUTHOR]

The European Higher Education Area (EHEA) has led to a new educational framework, focusing on the students and their lifelong learning and offering new educational opportunities for all. To achieve this, it is necessary that the university reconsider its educational model, fostering and encouraging an active student education through a deep planning of teaching and institutional organization. In the first section of this article,were view some examples of student-centered education models, taking into account the perspective of the institution, faculty and students. ICT also plays an important role in this paradigm shift. In the second part of this article, were view the potential contribution of these technological tools as facilitators of administration and management processes; we also analyze them as an specific subject of learning that allows students to face the new challenges of society through appropriate digital literacy and, above all, as facilitators of new models and strategies of training. [ABSTRACT FROM AUTHOR]