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In response to the issue of the size effect of helical anchors in deep-sea areas on their uplift bearing capacity, this study was proposed based on the ratio of the anchor shaft diameter to the anchor helix diameter and the ratio of the pitch to the anchor helix diameter. Eight sets of small-scale anchors were designed for laboratory model tests to study the impact of different anchor shaft diameters to anchor helix diameter ratios and the ratio of the pitch to the anchor helix diameter on uplift bearing capacity. The results indicate that smaller ratios of the anchor shaft diameter to the anchor helix diameter and the pitch to the anchor helix diameter can improve the uplift bearing capacity of helical anchors. In addition, this study found that the uplift bearing capacity of helical anchors decreased with the increase in the ratio of the anchor diameter to the anchor helix diameter and the ratio of the pitch to the anchor helix diameter. Based on this, a prediction equation for the uplift bearing capacity of helical anchors was proposed. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Dalian University of Technology / Dalian Ligong Daxue Xuebao is the property of Journal of Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The East Australian Current (EAC) exhibits significant variability across a wide range of spatial and temporal scales, from mesoscale eddies and meanders to seasonal, interannual, and decadal fluctuations in its intensity, pathway, and influence on the continental shelf circulation. Understanding and monitoring this variability is crucial because the EAC plays an important role in controlling shelf dynamics, regional circulation, coastal weather and global climate patterns. As such, two high-frequency (HF) coastal radar systems have been deployed on the east coast of Australia to measure surface currents upstream and downstream of the East Australian Current (EAC) separation point. The multi-year radar dataset (spanning 4–8 years) is presented here and its use is demonstrated to assess the spatial and temporal variability of the EAC and the adjacent continental shelf circulation, ranging from seasonal to interannual scales. The dataset is gap-filled using a 2dVar approach (after rigorous comparison with the traditional unweighted Least-squares fit (LS) method). Additionally, we explore the representation depth variability of the observations by comparing the data with surface Lagrangian drifter velocities (with and without depth drogues). The multi-year radar-derived surface current dataset, which was validated using short-term drifter and long-term current meter observations, revealed that the local upstream circulation is strongly dominated by the EAC's annual cycle, peaking in the austral summer. The analysis using 8 years of upstream data revealed the period of the EAC intensification at around 3–5 years. The interannual variability of the poleward transport downstream was driven by the intrinsic variability of the jet. This dataset which continues to be collected, complemented by numerical simulations and in-situ measurements, will provide a comprehensive view of the EAC's variability and its impact on the broader regional circulation dynamics which can be used for a range of dynamical investigations. [ABSTRACT FROM AUTHOR]

The issues of automating the air-to-air refueling of civilian aircraft are considered here. The main attention is paid to the stage of contacting of the "floating up" drogue with of the probe of refueling of the tanker aircraft. The options for implementing this technology are discussed, based on the automatic control loop of the tanker thrust in the mode of change according to the exponential law of approach speed as a function of the range between the refueling devices. To implement an exponential speed change program, it is proposed to use predictive control based on a dynamic process model. An alternative approach to automating the process of approaching the fueling devices involves using remote control of the unwinding of the fuel hose drum of the outboard fueling unit to control of the speed of approach of refueling devices. Such control is less inertial than controlling the flight speed of a multi-ton tanker. [ABSTRACT FROM AUTHOR]

Copyright of Revue des Lettres Modernes is the property of Classiques Garnier and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the realm of autonomous aerial refueling missions for unmanned aerial vehicles (UAVs), the controllable drogue represents a novel approach that significantly enhances both the safety and efficiency of aerial refueling operations. This paper delves into the issue of wide-range maneuverability control for the controllable drogue. Initially, a dynamic model for the variable-length hose–drogue system is presented. Based on this, a cooperative control framework that synergistically utilizes both the hose and the drogue is designed to achieve wide-range maneuverability of the drogue. To address the delay in hose retrieval and release, an open-loop control strategy based on neural networks is proposed. Furthermore, a closed-loop control method utilizing fuzzy approximation and adaptive error estimation is designed to tackle the challenges posed by modeling inaccuracies and uncertainties in aerodynamic parameters. Comparative simulation results show that the proposed control strategy can make the drogue maneuvering range reach more than 6 m. And it can accurately track the time-varying trajectory under the influence of model uncertainty and wind disturbance with an error of less than 0.1 m throughout. This method provides an effective means for achieving wide-range maneuverability control of the controllable drogue in autonomous aerial refueling missions. [ABSTRACT FROM AUTHOR]

Autonomous aerial refueling technology can significantly extend the operational endurance of unmanned aerial vehicles (UAVs), enhancing their ability to perform long-duration missions efficiently. In this paper, we address the identification of refueling drogues in the close docking phase of autonomous aerial refueling. We propose a high-precision real-time drogue recognition network called DREP-Net. The backbone of this network employs the DGST module for efficient feature extraction and improved representation of multi-scale information. For occlusion and complex background problems, we designed the RGConv module, which combines the re-parameterization module with the GhostNet idea to improve the detection of an occluded drogue. Meanwhile, we introduced the efficient local attention mechanism into the neck network to enhance the overall attention to the target region. Then, we designed Phead, a lightweight detection head that combines the advantages of decoupling and coupling heads to improve the detection speed. Finally, we compared our network with mainstream algorithms on a real drogue dataset, and the results show that DREP-Net has 2.7% higher mean average precision (mAP) compared to the YOLOv8n model, and the detection speed is improved by 31.4 frames per second. [ABSTRACT FROM AUTHOR]

The article discusses the book "Le temps du reportage. Entretiens avec les maîtres du journalisme littéraire" by Robert S. Boynton, which explores the genre of literary journalism. The book features interviews with prominent journalists such as Ted Conover, William Finnegan, and Jane Kramer, who discuss their methods and techniques in their respective fields. The author argues that non-fiction, particularly journalism, has become the most important form of literature in the United States. The article highlights the different approaches taken by these journalists, including immersive reporting, empathetic storytelling, and attention to detail, which contribute to the literary quality of their work. [Extracted from the article]

Aiming at the drogue docking control problem in aerial recovery, this paper proposes a performance event-triggered control algorithm based on disturbance observer to stabilize the flexibly towed aerial recovery drogue subject to the unknown airflows, cable towing tensions, limited computation capacity, and actuating power resources with guaranteed transient performance. Firstly, the control-oriented 6 degrees of freedom (DOF) affine nonlinear dynamics of the flexible cable-towed drogue are formulated. Then, the event-triggered extended state observers (ETESO) are established for the trajectory and attitude subsystems by utilizing intermittently measured state, to accurately estimate the lumped disturbances caused by the unmeasurable cable tension and unknown airflow disturbance while reducing the computation cost from the sensor to the observer. Moreover, to constrain the trajectory tracking error within the guaranteed transient performance constraint with any small overshoot, an ETESO-based event-triggered control algorithm for drogue was established to ensure the specified transient performance; finally, the closed-loop stability is discussed using Lyapunov analysis. The simulation results confirmed that this method can not only constrain the drogue within the expected small error range but also effectively reduce computational costs and resource occupation, with the best control effect. [ABSTRACT FROM AUTHOR]

The study aims to evaluate in real time the level of PTs' satisfaction with distance learning in three main aspects: lecturers, college's functioning and self-appraisal of learning practices with distance learning in a teacher training campus. It can be defined as an action research, to understand and improve the quality of the educative process in an agile way during the crisis. Through the lens of performance improvement theory, we sought to determine if Preservice Teachers satisfaction with learning remotely would change over time because of institutional preparedness and faculty support. The sample group consisted of n=183 PTs 'in the first semester (31% Return percentage), N=193 in the second semester (32% Return percentage) and N=284 (47% Return percentage in the third semester (out of 600 Preservice Teachers'). The findings indicate both challenges and successes. In the second and third semesters, PTs' reported higher levels of motivation, desire to learn, concentration taking an active part in class, and interest in the studied material, focusing on the lesson and ignoring distracting factors compared to the first semester. Preservice Teachers" coping with distance learning during the third semester were significantly better than the previous two semesters. Their evaluation of the lecturers' at third semester was significantly higher. Preservice Teachers has perceived the lecturers' role as an anchor of stability in the sea of change. The findings indicate the speed at which PTs's adopted the innovative changes during the crisis. However, their evaluation of the college at the second semester was better than at the first and third semesters. These findings are important, as they shine a spotlight on associations between PTs' satisfactions during times of change. [ABSTRACT FROM AUTHOR]

Screening items for parameter drift helps protect against serious validity threats and ensure score comparability when equating forms. Although many high-stakes credentialing examinations operate with small sample sizes, few studies have investigated methods to detect drift in small sample equating. This study demonstrates that several newly researched drift detection strategies can improve equating accuracy under certain conditions with small samples where some anchor items display item parameter drift. Results showed that the recently proposed methods mINFIT and mOUTFIT as well as the more conventional Robust-z helped mitigate the adverse effects of drifting anchor items in conditions with higher drift levels or with more than 75 examinees. In contrast, the Logit Difference approach excessively removed invariant anchor items. The discussion provides recommendations on how practitioners working with small samples can use the results to make more informed decisions regarding item parameter drift. [ABSTRACT FROM AUTHOR]

Forced mobility among homeless injection drug users and crack smokers in Montréal: This article focuses on the various actors in the urban setting who contribute to the increase in the forced mobility of homeless injection drug users and crack smokers in Montréal, Canada. The objective is to analyze who these actors are and how they contribute to increasing this forced mobility from the perspective of homeless injection drug users and crack smokers in relation to three needs : basic needs, acquisition of financial resources, and drug use. One hundred and six semi‐structured interviews were conducted among this population. The results indicate that various actors—police officers, community organization, peers, municipal administration, storekeepers, and residents—contribute to the forced mobility of this population in their daily activities. As for their needs, it is when they use drugs, sleep, or loiter that they are more likely to experience events of forced mobility. Police officers are by far the actors who contribute the most to this, often in a repressive way. The role of the municipality is also a determining factor in the daily activities of homeless injection drug users and crack smokers. Messages clés: Plusieurs types d'acteurs (policiers, organismes communautaires, pairs, administration municipale, commerçants et résidents) sont impliqués dans des évènements de mobilité forcée.Les policiers sont les plus impliqués dans les évènements de mobilité forcée.Concernant les besoins, consommer, dormir et occuper l'espace public sont à l'origine du plus grand nombre de déplacements forcés. [ABSTRACT FROM AUTHOR]

The KM3NeT-ARCA neutrino detector is the largest underwater neutrino telescope operating in the Mediterranean Sea at a depth of 3500 m, 100 km off the coast of Portopalo di Capo Passero (Italy). It is composed of strings anchored in the deep sea and kept vertical using a buoy. Each string hosts 18 Digital Optical Modules (DOMs), containing 31 optical sensors. The entire telescope, once completed, will be composed of 230 identical strings named Detection Units (DUs) that will send data to shore in real time. A Junction Box (JB) and an electro-optical cable permit the connection to the shore and the powering of the entire system. Each JB connects to the shore, handling up to 12 strings. It is a critical element that requires strict quality assurance rules. This article will focus on the quality assurance process that has allowed the JB to be a robust and reliable element of the entire KM3NeT-ARCA background network. [ABSTRACT FROM AUTHOR]

This case study analyzes the implications of deficit discourse on the daily conversations of a mother who requested forced treatment for her son. Data were analyzed drawing on social construction, with an emphasis on positioning theory and deficit discourse. Two episodes displaying deficit discourse were analyzed: one about the son as someone who is powerless, coping with drug use and another about the mother as someone unable to help her son. A sample letter was constructed using relational discourse, which provided new understandings for practice. Results support the benefits of collaborative and relational approaches for people who use drugs and for the emotional support of families. [ABSTRACT FROM AUTHOR]

Copyright of Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

When a Very-Low-Frequency (VLF) antenna is towed in a circular flightpath at a constant altitude, the spatial configuration of the antenna can become relatively stationary with the orbiting aircraft. Accordingly, a quasi-stationary model of the towed antenna is established based on the force balance, which can efficiently solve a large number of parameter optimization problems. This work studies the influence law of all relevant parameters, including the physical properties of the drogue and the towline, the flight conditions, the wind profile, and the phase of the flight. The results show that the towline verticality and towing force are highly sensitive to the flight conditions, wind profile, and the phase of the flight; followed by sensitivity to the towline itself, and slight sensitivity to the drogue. The flight conditions of the aircraft can change the verticality of the towline from 15% to 80% or more. In addition, as the maximum monthly average wind speed exceeds 7 m/s, the antenna system in hover will oscillate seriously, resulting in a range of up to 50% variation in towline verticality between different positions. [ABSTRACT FROM AUTHOR]

Copyright of Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Driven by global sulphur strategy, reducing sulfur emissions from the global shipping industry is of great significance for achieving sustainable development goals related to addressing climate change. This study explores the impact of government sulfur emission policies on the choice of mooring modes, include anchoring and drifting, for shipping lines. In this study, a bi-level programming model is constructed and linearized to minimize the total vessel emissions in emission control areas during the planning horizon and the total cost of each type of vessel. The leader of this model is the department that issues regulations and decides on the anchorage to regulate whether marine gas oil must be used. The followers are the shipping lines that execute transportation tasks and choose whether a vessel will anchor or drift. In addition, many numerical experiments and sensitivity analysis are conducted, and data and theoretical support for relevant decision-making are provided. [ABSTRACT FROM AUTHOR]

Achieving efficient electrocatalytic activity in two-dimensional (2D) MXene for advanced water splitting remains a significant challenge. In this work, 2D MXene was derived into sea urchin-like TiO 2 and used to load porous bimetallic phosphide (NiCoP x) nanorods to achieve three-dimensional (3D) TiO 2 -NiCoP x hierarchical heterostructures. The hierarchical heterostructures synthesized through hydrothermal and phosphating processes enable rich heterogeneous interfaces and fully exposed active sites, thereby facilitating efficient charge transfer and accelerating mass transfer rates. As a result, the TiO 2 -NiCoP x heterostructures inherit the low overpotential (311 mV at 10 mA cm−2) and long-term stability (current density retention of 94.1 % after 12 h) towards oxygen evolution reaction (OER). Importantly, the assembled TiO 2 -NiCoP x || Pt/C cell also exhibits remarkable water splitting performance. This contribution delivers a desirable opportunity for constructing efficient 2D MXene-based electrocatalysts with abundant active sites for water splitting. [Display omitted] • Hydrothermal strategy is proposed to construct 2D MXene derivatives. • Porous NiCoP x nanorods are tightly anchored on sea urchin-like TiO 2. • TiO 2 -NiCoP x hierarchical heterostructure exhibits excellent water splitting performance. [ABSTRACT FROM AUTHOR]

Drogue detection is a crucial component for autonomous aerial refueling. Drogue detection requires robust detection of the drogue in real time and different environments. A real-time embedded drogue detection method based on quantized convolutional neural networks is proposed in this paper to cope with this issue. A backbone network that is based on a multi-receptive field stem and multi-receptive field dense blocks are designed to quickly extract the features of images. An optimized detection network that is based on a depth-wise separable residual prediction block is used to achieve drogue detection in real time. A real aerial refueling dataset was built for training network model. A ground test and video sequences experiment were conducted to demonstrate the effectiveness, robustness, and real time of the proposed approach. [ABSTRACT FROM AUTHOR]

Here, sea urchin‐shaped nanoparticles were first fabricated by growing one dimensional polyaniline (1D PANI) nanowire array on carbon layer encapsulated Fe3O4 nanoparticles, and then Ag@AgCl photocatalyst were tightly anchored on the surface of PANI nanowire to form Fe3O4@C/1D PANI/Ag@AgCl bifunctional material as recyclable adsorption‐photocatalysts and surface enhanced Raman scattering (SERS) substrate to monitor photocatalytic degradation of dye molecules. Compared with Fe3O4@C/1D PANI, Ag@AgCl and Fe3O4@C/PANI/Ag@AgCl catalysts, the fast electron transfer characteristics of conductive 1D PANI nanowire array and the synergistic effect between the surface plasmon resonance of Ag and the photosensitive characteristic of AgCl, enabled the prepared Fe3O4@C/1D PANI/Ag@AgCl excellent adsorption‐photocatalytic efficiency for the degradation of RhB under visible‐light irradiation. PL spectra and a series of photoelectrochemical measurements were carried out to investigate the reasons for such enhanced photocatalytic activity and the possible improved photocatalytic degradation mechanism was proposed. Meanwhile, the detection of the presence of RhB and its degradation process were achieved with real‐time SERS technology employing the prepared Fe3O4@C/1D PANI/Ag@AgCl photocatalyst itself as the substrate. All the results made it great promise for simultaneously monitoring and removal of organic contaminants in water. [ABSTRACT FROM AUTHOR]

The birth of the nautical chart in the late medieval period is seen as a watershed moment in the history of cartography. So far, however, the artisanal practices that permitted the proliferation of sea charts have remained poorly understood and little evidence has been recovered from extant charts on which to base the production history of the surviving charts. This article describes a systematic exploration of the techniques employed in the copying of coastlines on manuscript charts between the fourteenth and early seventeenth centuries. Attention is drawn to the ways different processes shaped contemporary late-medieval and early-modern understanding of the Mediterranean and what the techniques may reveal of that thinking. By reframing the charts in terms of their characteristics as drawings and placing map making in the broader context of two-dimensional graphic art, and by making use of the ever-growing corpus of high-resolution digital reproductions, we gain new insights into the chartmakers' changing approaches to the transmission of geographical information. At the same time, a number of directions for further research are opened up. [ABSTRACT FROM AUTHOR]

This article, titled "Echoes of Azaleas," explores the experience of living with amnesia and the role of compassionate listening in supporting individuals with memory loss. The author recounts moments spent with their grandmother, who has forgotten that her husband has passed away and often repeats stories from her past. The author emphasizes the importance of being present, empathetic, and patient, as well as finding beauty in small moments and cherished memories. The article concludes by highlighting the vibrant azaleas as a symbol of the beauty found in these moments despite the challenges of amnesia. [Extracted from the article]

This paper presents analyses of drifters with drogues at different depths—1, 10, 30, and 50 m—that were deployed in the Mediterranean Sea to investigate frontal subduction and upwelling. Drifter trajectories were used to estimate divergence, vorticity, vertical velocity, and finite-size Lyapunov exponents (FTLEs) and to investigate the balance of terms in the vorticity equation. The divergence and vorticity are O(f) and change sign along trajectories. Vertical velocity is O(1 mm s−1), increases with depth, indicates predominant upwelling with isolated downwelling events, and sometimes changes sign between 1 and 50 m. Vortex stretching is one of the significant terms, but not the only one, in the vorticity balance. Two-dimensional FTLEs are 2 × 10−5 s−1 after 1 day, 2 times as large as in a 400-m-resolution numerical model. Three-dimensional FTLEs are 50% larger than 2D FTLEs and are dominated by the vertical shear of horizontal velocity. Bootstrapping suggests uncertainty levels of ~10% of the time-mean absolute values for divergence and vorticity. Analysis of simulated drifters in a model suggests that drifter-based estimates of divergence and vorticity are close to the Eulerian model estimates, except when drifters get aligned into long filaments. Drifter-based vertical velocity is close to the Eulerian model estimates at 1 m but differs at deeper depths. The errors in the vertical velocity are largely due to the lateral separation between drifters at different depths and are partially due to only measuring at four depths. Overall, this paper demonstrates how drifters, heretofore restricted to 2D near-surface observations, can be used to learn about 3D flow properties throughout the upper layer of the water column. Significance Statement: Drifting buoys, or drifters, are one of the oldest instruments in physical oceanography and have been used to study near-surface horizontal currents throughout the World Ocean. However, in flows with large vertical velocity or vertical shear, currents and transport properties change with depth, so conventional near-surface drifters are of limited use. This paper shows that a simultaneous release of drifters with drogues at different depths allows observing and quantifying both horizontal and vertical structure of the flow. Specifically, we present analyses of drifters with drogues at 1, 10, 30, and 50 m, which were deployed in the Mediterranean Sea in 2018. Drifter data are used to quantify such important flow properties as divergence, vorticity, vertical velocity, and finite-time Lyapunov exponents and to investigate the vorticity equation balance throughout the top 50 m of the water column. [ABSTRACT FROM AUTHOR]

Autonomous aerial refueling (AAR) can improve the aircraft’s combat effectiveness, and drogue visual tracking is one of the key technologies for the success of AAR. Target tracking is challenging as high-speed drogue often undergo abrupt motions, leaving the vision field, and significant hollow background variation over time. To address these challenges, a tracker based on multiparameter adaptive adjustment is proposed. First, we propose a background awareness module to perceive the hollow background of the drogue, which contributes to fully utilize background information. Second, the parameter and feature adaptation module is proposed to optimize the parameters and features by combining the information of drogue motion and the changing background. Finally, the tracking result is determined by the designed adaptive fusion module that conduces to the elevation of the tracking accuracy. The three modules are effectively merged, allowing our system to track the hollow object robustly and leading to superior results on the drogue videos experiment in the sky compared with state-of-the-art trackers. [ABSTRACT FROM AUTHOR]

The tracking and measurement methods of drogue in autonomous aerial refueling which based 2-D image, because of the loss of depth information, are susceptible to light changes, occlusion, etc., resulting in false tracking and the failure of position and orientation of drogue measurement, which may lead to collision of drones. In order to solve these problems, this article intends to introduce 3-D information to solve the position and orientation of drogue based on the original 2-D image tracking method. The method mainly includes two parts, tracking and measurement algorithms, using the decision function to effectively combine the two algorithms. The tracking algorithm provides a positioning area for the measurement algorithm, thereby reducing the amount of measurement operation data. The 3-D measurement result of the measurement algorithm based on stereo vision is used for measuring the drogue's position and orientation, and fed back to the tracking algorithm, which eliminates the candidate area and reduces the error rate to improve accuracy of the tracking algorithm. The measurement algorithm can still be realized stably high-precision under occlusion and no cooperation markers, which is not available in traditional 2-D image-based methods. We perform semiphysical simulation experiments to verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Copyright of Carnets: Revue Electronique d'Etudes Françaises / Revista Electrónica de Estudos Franceses is the property of Associacao Portuguesa de Estudos Franceses (APEF) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)