Practical Navigation Research Articles

An Improved Low-Cost Dual-Antenna GNSS Dynamic Attitude Determination Method in Complex Environments

GNSS attitude determination has been widely adopted due to its high efficiency, absence of cumulative errors, and ease of installation. However, practical navigation and attitude determination systems often rely on low-cost receivers that struggle with substantial multipath effects, frequent cycle slips, and satellite signal loss, significantly impairing attitude determination accuracy in challenging urban environments. To address this issue, this contribution proposes a constrained dynamic prediction model (C-Dynamics), which enables more accurate initial coordinates and thereby increases the effectiveness of the constrained LAMBDA (CLAMBDA) technique. To evaluate the practical performance of C-Dynamics, two sets of real-world data collected from a vehicle platform were analyzed. The results demonstrate that C-Dynamics significantly enhances the accuracy of initial coordinate estimations across various environments. Compared with the lambda method, the CLAMBDA method + C-Dynamics method (CLAMBDA+CD) improves the fixing rate in the urban environment by 5.6%, and the accuracy of the heading angle, pitch angle, and baseline length improved by 66%, 70.9%, and 84.2%, respectively. Moreover, in challenging high obstruction environments, the fixing rate increased by 43.5%, while the accuracy of heading angle, pitch angle, and baseline length improved by 76.4%, 69.2%, and 94%, respectively. The proposed algorithm effectively addresses the low fixing rate and insufficient accuracy of the LAMBDA method in high obstruction environments and holds practical value for widespread adoption in the mass market.

A playbook for mapping adolescent interactions with misinformation to perceptions of online harm

Digital misinformation is rampant, and understanding how exposure to misinformation affects the perceptions and decision-making processes of adolescents is crucial. In a four-part qualitative study with 25 college students 18–19 years old, we found that participants first assess the severity of harms (e.g., emotion, trust) that misinformation can cause, and then think about the possibilities for reputation harm, discrimination harm, or safety harm for certain kinds of misinformation. Qualities of misinformation including mis-contextualization, deceptive imagery, and impersonation factor into adolescent assessments. From these qualities, we developed a playbook for understanding adolescents’ perceptions of the harms caused by digital misinformation. This playbook can be used by researchers and technologists working to enhance and develop online governance standards by creating digital navigation practices to mitigate misinformation-related harm towards adolescents.

Response assessment in pediatric neurooncology (RAPNO) criteria revisited: a practical navigation guide for neuroradiologists.

The Response Assessment in Pediatric Neuro-Oncology (RAPNO) Working Group is an international, collaborative network of experts dedicated to pediatric central nervous system (CNS) tumors that was created in 2011. Since then, six RAPNO articles with imaging guidelines for response assessment in diverse pediatric tumor subgroups have been published, namely: 1) medulloblastomas and leptomeningeal seeding tumors (2018), 2) pediatric high-grade gliomas (2020), 3) pediatric low-grade gliomas (2020), 4) diffuse intrinsic pontine gliomas (2020), 5) pediatric intracranial ependymomas (2022) and 6) pediatric craniopharyngiomas (2023). The purpose of this article is to review all current available RAPNO criteria using a systematized and comparative approach centered on the role of neuroradiologists and supported by neuroimaging examples. Special emphasis will be placed on clarification of core concepts as well as practical adoption aspects of the RAPNO guidelines, namely how and when to image the brain and/or the spine; how to interpret the imaging findings; which other clinical, therapeutic and laboratory variables to consider; and finally how to apply the information to attribute the final appropriate response assessment classification.

Research and innovation of the “ship navigation radar” course based on the four‐in‐one approach in engineering education accreditation

AbstractTo achieve the strategic goal of marine and transportation power, it is imperative to cultivate highly skilled navigation professionals with a strong theoretical foundation and practical expertize. Seizing the opportunity by the “Double Thousand Plan” first‐class undergraduate courses initiated by the Ministry of Education, a four‐in‐one experimental teaching model is developed for ship navigation radar courses that integrate virtual reality technology under the context of engineering certification. The model encompasses land laboratory real training, maritime radar simulator training platform, comprehensive real‐ship training at sea, and virtual laboratory teaching and training. Through this innovative approach, students can acquire essential knowledge of ship navigation radar required for practical activities in navigation practice while honing their operational skills in positioning, navigation, and collision avoidance using radars. Furthermore, an analysis of course attainment and future development trends is conducted to provide insights into enhancing maritime education and fostering internationally competitive shipping talents.

The cartographic styles of Danube Delta

This study conducts an in-depth analysis of 820 maps with a focus on the western coast of the Black Sea, from Bilhorod-Dnistrovskyi to Cape Kaliakra, and gives special attention to the Danube Delta. The research highlights Pietro Vesconte’s critical role in the accurate depiction of the area and examines the stylistic developments over time and their effects on the mapping of the region. It also delves into the relationship between navigational practices and cartographic representation, noting the limited influence of Ottoman conquests on local mapping techniques. The study draws attention to a resurgence in the use of Ptolemaic principles, occurring simultaneously with the adoption of modern surveying techniques, such as triangulation. By concentrating on the Danube Delta and the adjacent coast of the Black Sea, the study provides a detailed understanding of the cartographic history of the area, highlighting the mix of precision and creative interpretation in maps.

Analysis of the impact of Arctic environment conditions on the psychophysical status of navigators and safety of ice navigation

Abstract The Arctic is a specific geographical region, whose environment effects any person's staying and working there, so it demands researching and accounting in the practice of ice navigation. The most difficult period of navigation is the winter-spring time, when Arctic Seas are covered by an ice cover. Ice navigation is always associated with a large number of difficulties for the crewmen, not only because of the geographical location of the water area, but also the climatic and environment conditions that impact on the mental and physical state of crewmen. These conditions, namely, the length of the polar night and day, the extreme frosts, maximum number of foggy days, and the duration of the ice period on all the tracks of the cargo ships along the North Sea Route were selected and analysed as the dominant factors that impact on the ship's crewmen. The analysis was performed on the base of the ‘Matrix of Arctic Impacts’ arraying that summarizes data about the level of the selected factors displayed in the local water areas along the North Sea Route and provided the selection of the local water areas with the most impacts of Arctic environment factors on the psychophysical status of the crewmen. In these water areas, accidents caused by the ‘human factor’ are most likely to occur. Therefore, special researches of the Arctic environment's impact on navigators is required in order to improve the safety of ice navigation.

Exploring Virtual Reality as an Employment Accommodation for Individuals With Albinism

Advances in virtual reality (VR) technology have created a wide range of remote work options. The goal of this study was to explore the experiences of individuals with albinism using VR work environments as a reasonable accommodation for remote work. Four cohorts of five participants each worked for 6 months at their leisure in a variety of virtual environments and met monthly with the research team to discuss positive and negative experiences with the technology and accessibility features. Using inductive thematic qualitative analysis, we followed a three-step coding process to identify themes in recorded transcripts of individual interviews and focus group discussions. The participants spent an average of 3.8 hours per week in VR, with an average session lasting 0.85 hours. From the coding analyses conducted by five coders, four themes were developed including the following: difficulties with VR’s limitations, recommendations for improving accessibility in VR, benefits that VR could bring to the workplace, and navigation practice applications for VR. While VR provided improved visual experiences for nearly all participants, there are needed features that could dramatically improve accessibility. Although individuals with low vision can customize many features of VR to optimize their visual experience, many of these accessibility features are specific to applications and not consistent across developers and hardware ecosystems. Despite its shortcomings, VR shows great promise as an accommodation for people with low vision. In particular, individuals participating in the current study found great utility in VR’s ability to assist with navigation of unfamiliar environments and its potential use in the workplace.

Ship autonomous collision avoidance decision from the perspective of navigation practice

Navigation safety is an eternal theme for ships, and it is an inherent strategic requirement for both transportation powers and maritime powers. With the development of intelligent ships, how to make intelligent decision-making results consistent with maritime practice is the key to navigation safety. This paper constructs a complex water area collision avoidance decision-making model that conforms to maritime practice, providing autonomous collision avoidance decision-making schemes for manned or unmanned ships. Firstly, based on the nonlinear velocity obstacle method, dynamic constraints such as ship maneuverability, target ship motion uncertainty, Convention on the International Regulations for Preventing Collisions at Sea (COLREGs), and good seamanship are fully considered, and a safe collision avoidance action plan is solved in the velocity domain; Then, by introducing an overshoot coefficient to improve the line of sight method, a feasible collision avoidance decision plan is derived by searching for a resumption navigation plan based on the safe avoidance action plan; Finally, collision avoidance decision plan is optimized to achieve autonomous collision avoidance decision-making for ships. To verify the effectiveness of the proposed model, a series of case studies, which focus on different encounter situations are designed and executed, the results indicate that the outcome of the model consistently aligns with real-world scenarios, which is in line with maritime practice.

Augmented reality navigation method based on image segmentation and sensor tracking registration technology

With the rapid development of modern science and technology, navigation technology provides great convenience for people's life, but the problem of inaccurate localization in complex environments has always been a challenge that navigation technology needs to be solved urgently. To address this challenge, this paper proposes an augmented reality navigation method that combines image segmentation and multi-sensor fusion tracking registration. The method optimizes the image processing process through the GA-OTSU-Canny algorithm and combines high-precision multi-sensor information in order to achieve accurate tracking of positioning and guidance in complex environments. Experimental results show that the GA-OTSU-Canny algorithm has a faster image edge segmentation rate, and the fastest start speed is only 1.8 s, and the fastest intersection selection time is 1.2 s. The navigation system combining the image segmentation and sensor tracking and registration techniques has a highly efficient performance in real-world navigation, and its building recognition rates are all above 99%. The augmented reality navigation system not only improves the navigation accuracy in high-rise and urban canyon environments, but also significantly outperforms traditional navigation solutions in terms of navigation startup time and target building recognition accuracy. In summary, this research not only provides a new framework for the theoretical integration of image processing and multi-sensor data, but also brings innovative technical solutions for the development and application of practical navigation systems.

Analysis of the peculiarities of the method of combining an electronic cartographic navigation information system with a ship's radar station

The article analyses the importance of radar image overlay on the screen of an electronic charting navigation information system (ECNIS) for improving safety and efficiency of navigation. Based on a review of scientific publications and professional literature, the article discusses the technical aspects of the overlay function, its advantages and limitations, and the impact on the decision-making process of a navigator. The overlay of radar information on an electronic navigation chart ensures the integration of planned and actual data on the environment, which contributes to the increase of situational awareness of the navigator. The combination of the systems makes it possible to visually compare radar targets with cartographic objects, clarify the vessel's location, control drift and orientation, and detect navigation hazards. The overlay function is especially valuable when sailing in confined waters and in conditions of limited visibility. At the same time, the use of overlay technology is associated with a number of technical difficulties and limitations related to ensuring the accuracy of overlap, harmonisation of data formats, and synchronisation of information updates. Errors in the operation of positioning systems, direction guidance, and cartography errors can lead to inconsistencies in image layers and incorrect interpretation of the navigation situation. The issues of equipment reliability, display parameters settings, competence and training of navigators are of critical importance. It is emphasised that radar image overlay on ECDIS is an effective tool for improving safety of navigation, but it does not replace traditional navigation practices and does not eliminate the need for critical evaluation of data. Over-reliance on technology, ignoring its limitations and disregard for the principles of good maritime practice can lead to erroneous decisions and have a negative impact on safety. Further prospects for the development of technology can be associated with the improvement of information processing algorithms, optimisation of human-machine interaction, and the development of training methods. The article emphasises the need for an integrated approach combining the improvement of technical systems and the human factor to fully realise the potential of the overlay function in ensuring safety of navigation. Only a balanced use of technological innovations and traditional navigational practices can guarantee the reliability and efficiency of modern navigation

Analysis of accidents in maritime transport using the method of Bayesian trust networks

Maritime incidents, though rare, have a significant impact on both the global economy and the environment. Improving maritime navigation practices always requires new ways to enhance safety, inevitably involving learning from past experiences and mistakes. In this context, probabilistic analysis of incidents and their associated consequences can play a crucial role in creating a safer and more efficient maritime transportation system. Bayesian networks constitute a class of probabilistic models based on statistics, decision theory, and graph theory. This paper describes the analysis of maritime incident statistics by selecting probabilistic parameters influencing the risk of their occurrence. Important parameters from this database are grouped, and a Bayesian network is constructed to illustrate the relationships between them. This, in turn, provides insight into the dependencies existing among the variables in the database and the fundamental reasons for these accidents. The data for this study are based on the Lloyds Register and IMO incident databases from 1990 to 2022. Key factors from this database are grouped, and a Bayesian network is built to show the relationships between the corresponding variables, providing an understanding of the probabilistic dependencies among the variables in the database and the primary causes of these incidents.

Navigational Practices and the Use of the Leeboard on Shallow Draft Riverine and Coastal Craft in the Yangzi and Rhine Estuaries

Both in the shallow Yangtze and Rhine deltas, flat-bottomed sailing craft made use of leeboards to prevent the drift of the ship when reaching or sailing close-hauled. Without a doubt, the leeboard was invented earlier in China, but contrary to what isoften suggested, the Dutch leeboard was not adopted from the Chinese example. Its invention should be considered an independent act, a case of convergence. The leeboard was introduced in the Low Countries simultaneously with the adoptionof the fore-and-aft ‘jib and spritsail’ rig and the transformation from narrow to broader ship hulls during the late Middle Ages. Over time the Dutch leeboard was further refined in form: deep and narrow leeboards for seagoing fishing vessels and round and shallow leeboards for the sailing barges and pleasure craft on lakes, canals, and rivers.

Competing Choreographies of the Postcolonial Plantation: Planter’s Pageantry Meets Sistren Collective’s Sweet Sugar Rage

This essay examines the 1985 documentary film, Sweet Sugar Rage (co-directed by Honor Ford-Smith and Harclyde Walcott), and its methodologies of renewable resistance to the enduring choreographies of planter's pageantry in the postcolonial Caribbean. Produced by Jamaica's Sistren Theatre Collective – a radical community theatre group formed in 1977 – the film (the collective's first) documents a set of dramatic interventions focused on women's labour exploitation in Jamaica's sugar cane fields. A series of workshops and plays depicts the historical and current material conditions of cane workers and aims to support participants in the practical navigation of plantation labour. In staging the material conditions of post-independence Jamaican plantation labour, including the gendered hierarchies of union organising, these counter-choreographies of workers' solidarity re-occupy the cane field as a historically dense site of collective resistance. Furthermore, I argue, in their rejection of the ubiquitous and insidious staging of the plantation as an ahistorical, hyper-aestheticised dreamscape of leisure and play, these local counter-choreographies intervene on the scale of global history. The essay articulates the stakes of this refusal by historicising the installation of plantation heritage tourism as a nostalgic site of planter's pageantry that continues to erase the violent legacies of enslaved and indentured labour into the present day. Engaging the aesthetic and political consequences of these competing choreographies, the essay looks towards the future of the Caribbean as a global proscenium of postcolonial possibility.

AONN+ Navigation Metrics That Support the Oncology Navigation Standards of Professional Practice

ObjectivesTo offer a comprehensive overview of the critical elements contributing to the achievements of oncology navigation, address challenges in standardized implementation, and examine recent advancements influencing the acknowledgment and reimbursement of navigation services. Lastly, the AONN+ 35 evidence-based navigation metrics will be shared, emphasizing the five core metrics that should be utilized by all navigation models in all settings. MethodsEmployed in this review involves synthesizing information from established oncology organizations, documenting the development of navigator professional standards of practice and navigation metrics that measure patient experience, clinical outcomes, and return on investment, and analyzing outcomes from national studies and collaborations to present a summary of advancements in oncology navigation. ResultsThe key components vital for ensuring the enduring success of programs encompass the core competencies of navigators, adherence to standards of navigation practice set by the Professional Oncology Navigation Taskforce, and the establishment of well-defined metrics specific to oncology navigation. ConclusionsDespite these advancements, challenges persist in implementing and recognizing the newly defined standards and metrics. Effective solutions involve aligning navigation programs with leadership, integrating standards into daily practice, defining navigator roles, measuring navigation program outcomes through defined metrics, and leveraging certifications. Standardized measurement and practice are imperative for national policy development and reimbursement models, aligning with the Cancer Moonshot's goal of high-quality, patient-centered, and cost-effective cancer care. Implications for Nursing PracticeTo contribute to standardizing measurement and practice in oncology navigation for national policy development and reimbursement models.

Perceptions Of Cadets On Visual Cues And Astronomical Learning In Maritime Safety And Navigation

This research explores the perceptions of 40 cadets at the Transportation Institute in Jakarta regarding the application of visual cues and astronomical learning in maritime safety and navigation. Through qualitative research methods, including interviews and observational techniques, the study examines cadets' proficiency in celestial navigation, their engagement with social media and citizen science initiatives related to astronomical learning, and their awareness of cultural differences in navigation practices. The findings reveal that cadets demonstrate a high level of proficiency in celestial navigation, indicating the effectiveness of the educational practices at the Transportation Institute. However, there is room for improvement in terms of leveraging social media for educational purposes and developing cross-cultural sensitivity among cadets. The research highlights the importance of integrating practical training, fostering cross-cultural competence, and promoting a culture of lifelong learning among cadets to ensure their preparedness for the modern maritime industry. The insights gained from this research can inform educational practices and professional development initiatives in the maritime sector.

The problem of winter navigation in the medieval Black Sea

Unlike the pre-industrial practice of winter navigation in the Mediterranean Sea, which has been the subject of numerous studies, winter seafaring on the medieval Black Sea has not previously been the subject of thorough scholarly investigation, not least because the available sources are relatively few and fairly circumstantial. Being aware of the limitations of the present survey, the author attempts to gather together and reinterpret several instances dating from the period of the Byzantine and Italian domination over the Black Sea, which can shed some light on the seamen's often complicated relation with the winter season. The majority of the extant sources date from the last two centuries of the Middle Ages, an era that witnessed substantial technological developments which contributed to the amelioration of winter navigation. This study chiefly aims to highlight the unresolved issues and address the challenges that such a topic of inquiry presents.

DRIFT ALIGNMENT: ASTRONOMY, CELESTIAL NAVIGATION, AND THE US-MEXICO BORDER

Drift Alignment is an ongoing body of work that engages the complex and contested history of the US-Mexico border through the practices of astrophotography and celestial navigation. My primary motivation for this work has been an examination of both the material and ideological conditions that led to the formation of the border, as well as its lasting relationship with colonialism, and the tragic consequences of immigration enforcement. Throughout the series, works oscillate between attempts at precision and its inverse — both subjective experience and mathematical error — to build a more poetic understanding of the region and its inhabitants. Photographic and video works in the series are based on a combination of archival information related to the border surveys during the mid-nineteenth century, eighteenth century Spanish missionary activity, and contemporary GIS data for migrant deaths in southern Arizona. Other work was produced during extended visits to sites that are tied to my past and present connection with the border, as well as historically significant locations that point to the shifting ways of perceiving and understanding of the lands of the American southwest.

Optimizing Multi-Vessel Collision Avoidance Decision Making for Autonomous Surface Vessels: A COLREGs-Compliant Deep Reinforcement Learning Approach

Automatic collision avoidance decision making for vessels is a critical challenge in the development of autonomous ships and has become a central point of research in the maritime safety domain. Effective and systematic collision avoidance strategies significantly reduce the risk of vessel collisions, ensuring safe navigation. This study develops a multi-vessel automatic collision avoidance decision-making method based on deep reinforcement learning (DRL) and establishes a vessel behavior decision model. When designing the reward function for continuous action spaces, the criteria of the “Convention on the International Regulations for Preventing Collisions at Sea” (COLREGs) were adhered to, taking into account the vessel’s collision risk under various encounter situations, real-world navigation practices, and navigational complexities. Furthermore, to enable the algorithm to precisely differentiate between collision avoidance and the navigation resumption phase in varied vessel encounter situations, this paper incorporated “collision avoidance decision making” and “course recovery decision making” as state parameters in the state set design, from which the respective objective functions were defined. To further enhance the algorithm’s performance, techniques such as behavior cloning, residual networks, and CPU-GPU dual-core parallel processing modules were integrated. Through simulation experiments in the enhanced Imazu training environment, the practicality of the method, taking into account the effects of wind and ocean currents, was corroborated. The results demonstrate that the proposed algorithm can perform effective collision avoidance decision making in a range of vessel encounter situations, indicating its efficiency and robust generalization capabilities.

The problem of implementing the concept of maximum integration of heterogeneous data in practical navigation

The topic of the work is the research of the problem of the practical realization of opportunistic navigation, which actually consists in the fact that the “signals of opportunity” are not optimized for global navigation according to their original purpose. A hypothesis about the possibility of strategic application of the navigation concept based on the principles of data integration with the objective existence of tactically surmountable difficulties is put forward. In the conditions of vulnerability of the global satellite system, an approach to use an additional source of combined signals in order to continuously ensure accurate geolocation of water transport vehicles is proposed. The comparative assessment confirms the comparability of the positioning error of alternative navigation with the data of classical satellite observations of mobile objects. An assumption about the effectiveness of spline modeling of the cartographic standard of informativeness for the practical organization of the basic principle of opportunistic positioning by analogy with the paradigm of correlation-extreme navigation is made. A computer visualization of a fixed fragment of the ocean gravitational field based on spline approximation is performed in order to optimize the problem of simultaneous localization and three-dimensional representation of the ship movement in a graphical environment unaffiliated with foreign software. A hybrid algorithm for mathematical synthesis of the navigational isosurface has been tested as a harmonized support for the navigation staff to implement the “terrain-referenced procedure” in the landscape coordinate space. The variants of the “ambiguity resolution” problem implementation in the issue of maximum integration of heterogeneous navigation data are considered. The probability of practical use of the opportunistic navigation postulates in marine applications, taking into account the “navigation gap” factor for leveling local satellite incapacity with a real possibility of countering malicious interception of ship control, is estimated. The expediency of using the factor of observational reckoning of the vessel path as an additional condition for navigation safety in the aspect of packet processing of the “signals of opportunity” slot is substantiated.

The bearings and distances isolines combinations of the navigational landmarks pair for the vessel fixed position determination

The issues of applying basic navigation parameters (bearing and distance), and their isolines traditionally used in navigation practice in coastal waters are studied in the paper. A new distinctive feature is the use of isolines combinations (three distance arcs, two isoazimuths, a hyperbola and an ellipse) based on measured bearings and distances to the pair of landmarks to obtain the vessel fixed positions with high precision. The traditional navigation methods (the theory of isolines, the generalized method of lines position, the method of least squares) are involved as a mathematical framework. The mathematical argumentation and the isolines characteristics of bearings and distances, their combinations (difference and sum of distances, difference of bearings) are given. The solutions of the surplus equations of the lines position under random error influence by the least squares method and the accuracy assessment of the vessel fix position by the radial error including the reduced variant to compensate the systematic errors are suggested. The principal points of the research are supported by the graphic interpretation, and the given expressions are adjusted to the practical application and navigation systems software development. The computer simulation that shows the radial error of the fixed position by seven position lines is at least two times less than by any pair of position lines has been carried out. The formalization of the proposed methods in the automatic navigation systems or in autonomous ship control systems will enable the navigator on board or at operating the vessel remotely to solve the problems of the navigation information processing in coastal and congested waters on a new level.