Articoli di riviste sul tema "Glider analysis"
Segui questo link per vedere altri tipi di pubblicazioni sul tema: Glider analysis.
Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili
Vedi i top-50 articoli di riviste per l'attività di ricerca sul tema "Glider analysis".
Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.
Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.
Vedi gli articoli di riviste di molte aree scientifiche e compila una bibliografia corretta.
1
Wu, Zhengxing, Junzhi Yu, Jun Yuan e Min Tan. "Analysis and verification of a miniature dolphin-like underwater glider". Industrial Robot: An International Journal 43, n. 6 (17 ottobre 2016): 628–35. http://dx.doi.org/10.1108/ir-03-2016-0095.
Abstract (sommario):
Purpose This paper aims to propose a novel design concept for a biomimetic dolphin-like underwater glider, which can offer the advantages of both robotic dolphins and underwater gliders to achieve high-maneuverability, high-speed and long-distance motions. Design/methodology/approach To testify the gliding capability of dolphin-like robot without traditional internal movable masses, the authors first developed a skilled and simple dolphin-like prototype with only gliding capability. The hydrodynamic coefficients, including lift, drag and pitching moment, are obtained through computational fluid dynamics method, and the hydrodynamic analysis in the steady gliding motion is also executed. Findings Experimental results have shown that the dolphin-like glider could successfully glide depending on the pitching torques only from buoyancy-driven system and controllable fins without traditional internal moveable masses. Originality/value A hybrid underwater glider scheme that combines robotic dolphin and glider is firstly proposed, shedding light on the creation of innovation gliders with maneuverability and durability.
2
Du, Xiaoxu, e Lianying Zhang. "Analysis on energy consumption of blended-wing-body underwater glider". International Journal of Advanced Robotic Systems 17, n. 2 (1 marzo 2020): 172988142092053. http://dx.doi.org/10.1177/1729881420920534.
Abstract (sommario):
As a new type of underwater observation platform, underwater glider is widely used in marine explorations and military surveys, and most gliders are powered by their own batteries whose capacities are limited. It is therefore necessary to analyze the energy consumption of underwater glider. In this article, the variation law of seawater density changing with depth is considered; based on the theory of rigid body dynamics, the motion model of blended-wing-body underwater glider is established; the energy consumption model of each component module is accounted by analyzing the energy consumption composition in the working process of blended-wing-body underwater glider; and the energy consumption under different navigation depths, different glide ratios, and different buoyancy adjustments regulation is simulated. The results demonstrate that as the glide depth is increased, the total energy consumption increases in a single cycle and decreases per gliding distance, leading to a smaller energy consumption ratio for the attitude adjustment module; on the other hand, as the buoyancy adjustment is increased, more energy is consumed in a single cycle and less energy is consumed per gliding distanced, resulting in a larger energy consumption ratio for the attitude adjustment module. As the glide ratio increases, the total energy consumption in a single cycle first increases and then decreases, while the energy consumption of per gliding distance and the energy consumption ratio of the attitude adjustment module are decreased.
3
Ji, Dae-Hyeong, Jung-Han Lee, Sung-Hyub Ko, Jong-Wu Hyeon, Ji-Hyeong Lee, Hyeung-Sik Choi e Sang-Ki Jeong. "Design and Analysis of the High-Speed Underwater Glider with a Bladder-Type Buoyancy Engine". Applied Sciences 13, n. 20 (16 ottobre 2023): 11367. http://dx.doi.org/10.3390/app132011367.
Abstract (sommario):
This study entailed the design and analysis of a 400 m class underwater glider operated by a bladder-type buoyancy engine. The underwater glider was designed for high-speed movement with a maximum velocity of 2 knots. The shape of the hull was designed to reduce water resistance using the Myring hull profile equation. The reliability was verified by performing simulations using resistance coefficients. The relationship between the control value of the ballast discharged from the buoyancy engine and the glider’s speed according to the path angle was analyzed. Further, the relationship between the optimal glide angle and the design control value of the ballast was derived, and the optimal glider speed was estimated accordingly. Based on the analysis results, a bladder-type buoyancy engine was developed, and the maximum speed of the tested underwater glider was measured via sea trials.
4
Mohd Ali, Zurriati, Jasmine Demi Danny Jabing e Zulhilmy Sahwee. "Fabrication of UiTM’s Energy Glider". JOURNAL OF APPLIED ENGINEERING DESIGN AND SIMULATION 3, n. 1 (29 marzo 2023): 1–10. http://dx.doi.org/10.24191/jaeds.v3i1.56.
Abstract (sommario):
Glider is a fixed-wing aircraft which does not depend on the engine. A glider can fly for an extended period depending on the design and area of the lifting surface. Just like any other aircrafts, the design of wings is crucial to produce lift force to keep aircraft in the air. Gliders have long wings and is designed to be lightweight which allows it to have a high lift-to-drag ratio (L/D) to glide at a long distance. The maximum lift-to-drag ratio, 〖(L/D〗_max) can indicate how far the glider will glide as it is one of the most important performance parameters. This project aims to design, build, and fly an energy glider. Prior on the design of the energy glider, statistical analysis has been done by comparing data from many studies to aid in determining the initial values of the glider. Then, the general design of the energy glider has been decided during the preliminary design. To support the design decision made, ANSYS Fluent software has been used to study flow of air over KFm-5A aerofoil profile which has been chosen during the early stages of design. The model of the energy glider was then designed in CATIA V5 software with a wingspan of 1.52 m and fuselage length of 0.69 m. Lastly, flight test was conducted to achieve the project’s objective. During the flight test, the glider reached a ceiling height of approximately 300 m and obtained a velocity of 144 km/h. The analysis of the glider performance will be used as an aircraft data for future research.
5
Orozco-Muñiz, Juan Pablo, Tomas Salgado-Jimenez e Noe Amir Rodriguez-Olivares. "Underwater Glider Propulsion Systems VBS Part 1: VBS Sizing and Glider Performance Analysis". Journal of Marine Science and Engineering 8, n. 11 (14 novembre 2020): 919. http://dx.doi.org/10.3390/jmse8110919.
Abstract (sommario):
The Variable Buoyancy System (VBS) is a critical device in the operation of underwater gliders that should be properly sized to achieve the required vehicle propulsion; safety within the operating range; and adequate efficiency at the nominal depth rating. The VBS budget volume depends mainly on the glider hydrodynamics and the main operating states of the vehicle. A method is proposed with analytical equations to analyze the performance of underwater gliders and to estimate the resultant velocities of the vehicle as a function of the buoyancy change and the glider angle. The method is validated to analyze the glider performance of underwater gliders and is essential to get the main design requirement for the propulsion system: the VBS budget volume. The paper presents the application of the method to obtain the VBS sizing for an academic glider; a comparison with the historical hydrodynamic data of the Slocum glider; the results of the glider performance study; and the development of the characteristic charts necessary to evaluate the performance of the vehicle and its flight parameters.
6
Rudnick, Daniel L., Russ E. Davis e Jeffrey T. Sherman. "Spray Underwater Glider Operations". Journal of Atmospheric and Oceanic Technology 33, n. 6 (giugno 2016): 1113–22. http://dx.doi.org/10.1175/jtech-d-15-0252.1.
Abstract (sommario):
AbstractOperational statistics for the Spray underwater glider are presented to demonstrate capabilities for sustained observations. An underwater glider is an autonomous device that profiles vertically by changing buoyancy and flies horizontally on wings. The focus has been on sustained observations of boundary currents to take advantage of the glider’s small size, which allows it to be deployed and recovered from small vessels close to land, and the fine horizontal resolution delivered by the glider, which is scientifically desirable in boundary regions. Since 2004, Spray underwater gliders have been deployed for over 28 000 days, traveling over 560 000 km, and delivering over 190 000 profiles. More than 10 gliders, on average, have been in the water since 2012. Statistics are given in the form of histograms for 297 completed glider missions of longer than 5 days. The statistics include mission duration, number of dives, distance over ground, and horizontal and vertical distance through water. A discussion of problems, losses, and short missions includes a survival analysis. The most extensive work was conducted in the California Current system, where observations on three across-shorelines have been sustained, with 97% coverage since 2009. While the authors have certain advantages as developers and builders of the Spray underwater glider and Spray may have design and construction advantages, they believe these statistics are a sound basis for optimism about the widespread future of gliders in oceanographic observing.
7
Yang, Canjun, Shilin Peng e Shuangshuang Fan. "Performance and Stability Analysis for ZJU Glider". Marine Technology Society Journal 48, n. 3 (1 maggio 2014): 88–103. http://dx.doi.org/10.4031/mtsj.48.3.6.
Abstract (sommario):
AbstractUnderwater gliders provide an effective, low-cost method for sampling the ocean over large spatial and temporal scales. In this paper, we present a series of theoretical analyses to provide guidelines for vehicle design, which are used to develop a coastal 200-m-depth underwater glider known as the Zhejiang University (ZJU) glider. The ZJU glider uses a longitudinally actuated moving mass for pitch control and a rudder for turning control. Computational methods and analytical approaches are chosen to solve the viscous and inviscid terms of glider hydrodynamics, respectively. Steady flight equilibrium analysis gives the varied range of moving mass location for pitch control and varied vehicle volume for buoyancy control. Size analysis investigates the effects of glider geometric parameters on motion performance. For wings-level flight, we describe the variation in the maximum lift-to-drag ratio corresponding to a given vehicle size and speed. For turning motion, we investigate the manner in which the turning performance varies with vertical rudder configuration. Stability analysis determines the relationship between the stability of glider motion and the locations of the glider wings and rudder. Pool trials indicate that the ZJU glider functions well in water and is capable of serving as a sensor platform for ocean sampling.
8
Beer, Randall D. "The Cognitive Domain of a Glider in the Game of Life". Artificial Life 20, n. 2 (aprile 2014): 183–206. http://dx.doi.org/10.1162/artl_a_00125.
Abstract (sommario):
This article examines in some technical detail the application of Maturana and Varela's biology of cognition to a simple concrete model: a glider in the game of Life cellular automaton. By adopting an autopoietic perspective on a glider, the set of possible perturbations to it can be divided into destructive and nondestructive subsets. From a glider's reaction to each nondestructive perturbation, its cognitive domain is then mapped. In addition, the structure of a glider's possible knowledge of its immediate environment, and the way in which that knowledge is grounded in its constitution, are fully described. The notion of structural coupling is then explored by characterizing the paths of mutual perturbation that a glider and its environment can undergo. Finally, a simple example of a communicative interaction between two gliders is given. The article concludes with a discussion of the potential implications of this analysis for the enactive approach to cognition.
9
Sun, Weicheng, Wenchuan Zang, Chao Liu, Tingting Guo, Yunli Nie e Dalei Song. "Motion Pattern Optimization and Energy Analysis for Underwater Glider Based on the Multi-Objective Artificial Bee Colony Method". Journal of Marine Science and Engineering 9, n. 3 (16 marzo 2021): 327. http://dx.doi.org/10.3390/jmse9030327.
Abstract (sommario):
Underwater gliders are prevailing in oceanic observation nowadays for their flexible deployment and low cost. However, the limited onboard energy constrains their application, hence the motion pattern optimization and energy analysis are the key to maximizing the range of the glider while maintaining the acceptable navigation preciseness of the glider. In this work, a Multi-Objective Artificial Bee Colony (MOABC) algorithm is used to solve the constrained hybrid non-convex multi-objective optimization problem about range and accuracy of gliders in combination with specific glider dynamics models. The motion parameters Pareto front that balances the navigational index referring to range and preciseness are obtained, relevant gliding profile motion results are simulated simultaneously, and the results are compared with the conventional gliding patterns to examine the quality of the solution. Comparison shows that, with the utilization of the algorithm, glider voyage performance with respect to endurance and preciseness can be effectively improved.
10
bin Ibrahim, Mohamad Faizul, Ovinis Mark e Kamarudin bin Shehabuddeen. "An Underwater Glider for Subsea Intervention: A Technical Feasibility Study". Applied Mechanics and Materials 393 (settembre 2013): 561–66. http://dx.doi.org/10.4028/www.scientific.net/amm.393.561.
Abstract (sommario):
An underwater glider is a type of autonomous underwater vehicle that moves based on small changes in its buoyancy, maneuvering using it wings as it glides through the water. These gliders, currently used in oceanographic sampling, may potentially be used to deliver payloads for subsea intervention at a lower net transport economy (NTE). Net transport economy, is a measure of the cost of transport in terms of the energy consumed per meter traveled, for each kilogram of loaded mass in air or net buoyancy underwater. The current method of payload delivery is either by using customized support vessel or remotely operated vehicle. This paper presents a technical feasibility study of extending the use of these gliders for subsea intervention, with emphasis on payload delivery. Important aspects of an underwater glider such as its volume (size), speed, wing area, wing span, operational depth and net transport economy were considered. The analysis was based on mathematical models governing existing gliders such as legacy gliders and the XRAY Liberdade. The results obtained were validated by extrapolating the present state of the art in underwater gliders to the proposed future use of these gliders, which is for payload delivery. In conclusion, the use of underwater gliders for subsea intervention is feasible based on factors considered in this study.
11
Xie, Taotao, Jiawei Zhang, Dawei Xiao e Qing Ji. "Analysis of Electromagnetic Field Characteristics of Wave Glider". Applied Sciences 14, n. 11 (1 giugno 2024): 4800. http://dx.doi.org/10.3390/app14114800.
Abstract (sommario):
A wave glider is an ocean observation platform that utilizes wave energy to drive and solar energy to power. Its metal structure will generate related electromagnetic fields due to corrosion and underwater motion. In the detection of weak electromagnetic field signals underwater, its own electromagnetic field characteristics will have an impact on signal detection. To study the applicability of electric field sensors and magnetic field sensors on wave glider platforms, the structural characteristics of the wave glider were analyzed, and the installation positions of electric field sensors and magnetic field sensors were designed based on the different motion states of the water surface mother body and underwater towing body. The measured electromagnetic field data of the wave glider platform were measured, and the measured data were analyzed. It was determined that the interference electric field energy under typical working conditions of the wave glider was mainly concentrated within 1 Hz, which decreased with increasing frequency, and the magnitude was mV/m. The magnitude of the interference magnetic field is several tens of nT, indicating that the electromagnetic field interference is significant during the working state of the wave glider. Installing an electric field sensor directly at the bottom of the wave glider will cause significant noise interference, while installing the magnetic field sensor directly at the bottom of the tractor will affect the servo and the shaking-induced magnetic field. Moreover, wave gliders should not use electric field signals below 1 Hz as signal sources, but they can utilize axial frequency electromagnetic fields to detect weak electromagnetic signals underwater.
12
Jia, Li Juan, Zhan Feng Qi, Sen Zhang, Yu Feng Qin, Jian Shi, Xuan Ming Zhang e Xiu Jun Sun. "Dynamic Analysis of the Acoustic Velocity Profile Observation Underwater Glider". Applied Mechanics and Materials 475-476 (dicembre 2013): 50–54. http://dx.doi.org/10.4028/www.scientific.net/amm.475-476.50.
Abstract (sommario):
Underwater gliders carried acoustic velocity meters can realize ocean profile observations of the acoustic velocity for long duration and large scale. This paper mainly studies the kinematics and hydrodynamics of the Slocum underwater glider carrying a acoustic velocity meter MINOSX with length 565mm and diameter 76mm. Thus, theory reference for optimal design parameters of the underwater glider is proposed. By establishing the kinematic equations and giving some related parameters, variations with time of the steady-state gliding velocity, pitch angle, gliding path and attack angle are simulated by using Matlab software; The simulation calculations of the hydro-drag and lift are completed by using Fluent software. Finally, this paper summarizes the dynamic characteristics in steady state of the underwater glider in longitudinal plane.
13
Bruvik, Erik M., Ilker Fer, Kjetil Våge e Peter M. Haugan. "A revised ocean glider concept to realize Stommel's vision and supplement Argo floats". Ocean Science 16, n. 2 (6 marzo 2020): 291–305. http://dx.doi.org/10.5194/os-16-291-2020.
Abstract (sommario):
Abstract. This paper revisits Stommel's vision for a global glider network and the Argo design specification. A concept of floats with wings, so-called slow underwater gliders, is explored. An analysis of the energy or power consumption shows that, by operating gliders with half the vehicle volume at half the speed compared to present gliders, the energy requirements for long-duration missions can be met with available battery capacities. Simulation experiments of slow gliders are conducted using the horizontal current fields from an eddy-permitting ocean reanalysis product. By employing a semi-Lagrangian, streamwise navigation whereby the glider steers at right angles to ocean currents, we show that the concept is feasible. The simulated glider tracks demonstrate the potential for efficient coverage of key oceanographic features and variability.
14
Fan, Shuangshuang, e Craig Woolsey. "Elements of Underwater Glider Performance and Stability". Marine Technology Society Journal 47, n. 3 (1 maggio 2013): 81–98. http://dx.doi.org/10.4031/mtsj.47.3.4.
Abstract (sommario):
AbstractUnderwater gliders are winged autonomous underwater vehicles (AUVs) that can be deployed for months at a time and travel thousands of kilometers. As with any vehicle, different applications impose different mission requirements that impact vehicle design. We investigate the relationship between a glider’s geometry and its performance and stability characteristics. Because our aim is to identify general trends rather than perform a detailed design optimization, we consider a generic glider shape: a cylindrical hull with trapezoidal wings. Geometric parameters of interest include the fineness ratio of the hull, the wing position and shape, and the position and size of the vertical stabilizer. We describe the results of parametric studies for steady wings-level flight, both at minimum glide angle and at maximum horizontal speed, as well as for steady turning flight. We describe the variation in required lung capacity and maximum lift-to-drag ratio corresponding to a given vehicle size and speed; we also consider range and endurance, given some initial supply of energy for propulsion. We investigate how the turning performance varies with wing and vertical stabilizer configuration. To support this analysis, we consider the glider as an 8-degree-of-freedom multibody system (a rigid body with a cylindrically actuated internal moving mass) and develop approximate expressions for turning flight in terms of geometry and control parameters. Moving from performance to stability and recognizing that a glider’s motion is well described in terms of small perturbations from wings-level equilibrium, we study stability as an eigenvalue problem for a rigid (actuators-fixed) flight vehicle. We present a number of root locus plots in terms of various geometric parameters that illuminate the design tradeoff between stability and control authority.
15
L'Hévéder, Blandine, Laurent Mortier, Pierre Testor e François Lekien. "A Glider Network Design Study for a Synoptic View of the Oceanic Mesoscale Variability". Journal of Atmospheric and Oceanic Technology 30, n. 7 (1 luglio 2013): 1472–93. http://dx.doi.org/10.1175/jtech-d-12-00053.1.
Abstract (sommario):
Abstract This study presents an Observing System Simulation Experiment (OSSE) with a network of gliders in a realistic mesoscale field of eddies and filaments. The main objective is to demonstrate that the analysis skill evaluation, performed with different statistics, determines the optimal number of gliders needed to survey a “glider observatory” with a given simple topology of the glider array, in the shape of a “double comb.” Metrics, based on a spatial interpolation of the sampled data with a multiscale objective analysis method, are elaborated to evaluate the reconstruction of the three-dimensional temperature field with several glider networks, at a weekly time scale. The mesoscale structures obtained by the optimal network (front, eddies, eddies detachment) are also compared with the structures of the original simulation. This comparison demonstrates the efficiency of a glider fleet to sample a well-defined area at a given spatiotemporal scale. In this particular situation (midlatitude region, domain of 400 km × 600 km, reconstruction of weekly snapshots), the optimum network is composed of 10 gliders. A relationship is highlighted between the spatial scales of the sampled area, the physical characteristics of the studied region, the reconstruction time scale, and the optimum number of gliders. The results presented here can be applied to design an actual in situ experiment.
16
Tian, Xin, Lianhong Zhang e Hongwei Zhang. "Research on Sailing Efficiency of Hybrid-Driven Underwater Glider at Zero Angle of Attack". Journal of Marine Science and Engineering 10, n. 1 (26 dicembre 2021): 21. http://dx.doi.org/10.3390/jmse10010021.
Abstract (sommario):
The sailing efficiency of an underwater glider, an important type of marine environment detection and data collection equipment, directly affects its range and duration. The zero-angle-of-attack gliding can be achieved by adjusting the wing installation angle to minimize the drag and improve the sailing efficiency, and thus further improving performance of the glider. This paper first presents the dynamic characteristics of a hybrid-driven underwater glider with a certain wing installation angle when it is sailing at zero angle of attack in buoyancy-driven mode and hybrid-driven mode. In buoyancy-driven mode, with a given wing installation angle, the glider can achieve zero-angle-of-attack gliding only at a specific glide angle. In hybrid-driven mode, due to the use of a propulsion system, the specific glide angle that allows the zero-angle-of-attack gliding in buoyancy-driven mode is expanded to a glide angle range bounded by zero degrees. Then, the energy consumption per meter is introduced as an indicator of sailing efficiency, and the effects of glide angle and wing installation angle on sailing efficiency of the zero-angle-of-attack glider in two driving modes are studied under the conditions of given net buoyancy and given speed, respectively. Accordingly, the optimal wing installation angle for maximizing the sailing efficiency is proposed. Theoretical analysis shows that the sailing efficiency of a zero-angle-of-attack glider can be higher than that of a traditional glider. Considering the requirements of different measurement tasks, a higher sailing efficiency can be achieved by setting reasonable parameters and selecting the appropriate driving mode.
17
Ma, Wei, Yanhui Wang, Shuxin Wang, Gege Li e Shaoqiong Yang. "Optimization of hydrodynamic parameters for underwater glider based on the electromagnetic velocity sensor". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, n. 14 (31 marzo 2019): 5019–32. http://dx.doi.org/10.1177/0954406219840372.
Abstract (sommario):
With the development of autonomous underwater glider technology, the gliders integrated with multitype sensors have been widely applied in the ocean scientific research. Among those sensors, electromagnetic velocity sensor provides a new way to acquire the unknown parameters of Petrel‐II glider. Based on the analysis of computational fluid dynamics, the optimized layout position and distance of electromagnetic velocity sensor is determined. Petrel‐II integrated with electromagnetic velocity sensor conducted a series of sea‐trials to obtain sailing data under different attitudes. By combining sea‐trial data with dynamic model of deepsea glider, the relationships between pitch, hydrodynamic forces/moment, and angle of attack are yielded. The buoyance model in the dynamics is validated by suspension experiment of glider. The dynamic simulations in the longitudinal plane with different hydrodynamic parameters obtained by, that is, optimization with electromagnetic velocity sensor, data statistical analysis combining computational fluid dynamics and parameter identification, and calculation by computational fluid dymanics, are conducted and compared with experimental results to verify validity and accuracy of those parameters. Results show that hydrodynamic parameters optimized by integrating electromagnetic velocity sensor on the glider can exhibit dynamic behavior more accurately. This work contributes to the calculation of vertical water velocities from glider and theoretical research of glider.
18
Liu, Yanji, Jie Ma, Ning Ma e Zhijian Huang. "Experimental and Numerical Study on Hydrodynamic Performance of an Underwater Glider". Mathematical Problems in Engineering 2018 (30 agosto 2018): 1–13. http://dx.doi.org/10.1155/2018/8474389.
Abstract (sommario):
The hydrodynamic coefficients are important parameters for predicting the motion of the glider and upgrading the hull design. In this paper, based on the Reynolds number similarity theory, 6 degrees of freedom (DOFs) of the fluid force and torque of a 1:1 full-scale glider model are measured. The present measurements were carried out at (2 - 14m/s) by varying attack angles and sideslip angles (-9 - 9°), respectively. The measurements were used to study the variation of the hydrodynamics of the glider, and the measurements have also been used to validate results obtained from a CFD code that uses RNG k-ε. The hydrodynamic force coefficients obtained from CFD accord well with the measurements. However, the torque coefficients difference is fairly large. Dynamics simulation results show that CFD results can be used to design and study the motion characteristics of gliders. In order to simplify the design process of gliders, we fit the empirical formula based on the experimental data and obtain a drag coefficient equation with Reynolds number. The influence of two kinds of appendages of the Conductance-Temperature-Depth (CTD) unit and thruster unit on the glider drag were studied by a contrast test. The analysis results can provide reference for design and the motion investigate of gliders.
19
Quin, D., R. Goldingay, S. Churchill e D. Engel. "Feeding Behaviour and Food Availability of the Yellow-Bellied Glider in North Queensland." Wildlife Research 23, n. 6 (1996): 637. http://dx.doi.org/10.1071/wr9960637.
Abstract (sommario):
The diet of the yellow-bellied glider (Petaurus australis) was examined at a site in north Queensland by extensive observation of individuals from 10 glider groups. The diet was assessed in four seasons over 12 months by collating large numbers of qualitative feeding observations and by analysis of faeces. Data were also collected on flowering and bark shedding in the forest. Sap feeding accounted for more than 80% of the feeding observations throughout the year. Nectar and pollen of eucalypts (Eucalyptus spp.) and banksias (Banksia spp.) accounted for much of the remainder of the diet although arthropods and honeydew were present in spring and summer. Faecal analysis was based on much smaller sample sizes but confirmed the qualitative result obtained from direct observations. It also revealed the presence of a wide variety of pollen types. Many of these could be attributed to incidental ingestion but at least six rain forest genera were moderately common in faeces, which is consistent with observations of brief and infrequent visits by gliders to these trees. Examination of eucalypt, banksia and other pollen types showed that 60-70% of pollen was devoid of cell contents, supporting earlier suggestions that gliders obtained protein from pollen digestion, but at this site also from harvesting arthropods. This study confirms the dependence of the yellow-bellied glider in north Queensland on the sap of the red stringybark (Eucalyptus resinifera) and that conservation of the yellow-bellied glider is intimately associated with the management of this tree species. The use of various species for nectar and pollen suggests that the yellow-bellied glider may be an important pollinator in these forests. Moreover, sap from the wounds created by gliders is used by a range of other animal species. These observations suggest that the yellow-bellied glider is likely to be a keystone species in the open-forest ecosystems of north Queensland and that it deserves special emphasis in management.
20
ORKISZ, Marek, Piotr WYGONIK, Michał KUŹNIAR e Maciej KALWARA. "Analysis of the possibility of using an engine with a rotating piston as the propulsion of an electric generator in application to a motor glider propulsion". Combustion Engines 178, n. 3 (1 luglio 2019): 264–68. http://dx.doi.org/10.19206/ce-2019-346.
Abstract (sommario):
Analysis of the possibility of using an engine with a rotating piston as the propulsion of an electric generator in application to a motor glider propulsion The paper presents an analysis of the possibilities of application of a rotating piston engine (Wankel type) as a propulsion for an electric generator in the motor glider propulsion system. This generator would be a part of the propulsion system of a hybrid motor glider using the AOS 71 motor glider airframe. In the research, the rotational characteristics of the LCR 407ti engine were determined experimentally. Driving torque run, power and fuel consumption were determined as a function of engine speed. The obtained results are presented in diagrams. The conceptual diagram of the hybrid drive is presented. The current generator was selected and the effectiveness of the generator and the entire propulsion were assessed from the motor gliders performance point of view. On the basis of the conducted research, conclusions were drawn and there were indicated the objectives and directions of further research on hybrid propulsion with specific aerodynamic and mass limitations of the aircraft
21
Woodd, Carly, Natasha A. Czarny, Ian M. G. Gunn e Wayne Sturrock. "Faecal steroid analysis and urinary cytology of the squirrel glider (Petaurus norfolcensis)". Australian Journal of Zoology 54, n. 4 (2006): 277. http://dx.doi.org/10.1071/zo06019.
Abstract (sommario):
Non-invasive techniques were used to investigate the reproductive biology of captive squirrel gliders (Petaurus norfolcensis) for 3 months during the breeding season. The squirrel glider is a medium-sized marsupial glider of eastern Australia and is currently listed as a threatened species as a result of habitat destruction and fragmentation. Urinary cytology was used to determine the timing of oestrus, and the presence of sperm confirmed mating. Progesterone and oestradiol-17β were identified in faecal samples via thin-layer chromatography, and were used to characterise the reproductive cycle. Reproductive activity was observed in three of four females, with births occurring during June and July. A preoestrus increase in faecal oestradiol-17β was detected in a single female, whilst significant increases occurred post partum (±2 days) in two of four females, suggesting that the squirrel glider may undergo a postpartum oestrus. Faecal progesterone profiles showed low concentrations before oestrus and significantly elevated concentrations after oestrus, which were maintained throughout pregnancy. Parturition coincided with a decrease in progesterone concentrations (±1 day). This study successfully used non-invasive monitoring of urinary cytology and faecal steroids to define luteal and gestational length as 16–17 days, a previously unpublished detail.
22
Soanes, Kylie, Peter A. Vesk e Rodney van der Ree. "Monitoring the use of road-crossing structures by arboreal marsupials: insights gained from motion-triggered cameras and passive integrated transponder (PIT) tags". Wildlife Research 42, n. 3 (2015): 241. http://dx.doi.org/10.1071/wr14067.
Abstract (sommario):
Context Wildlife crossing structures are installed to mitigate the impacts of roads on animal populations, yet little is known about some aspects of their success. Many studies have monitored the use of structures by wildlife, but studies that also incorporate individual identification methods can offer additional insights into their effectiveness. Aims We monitored the use of wildlife crossing structures by arboreal marsupials along the Hume Freeway in south-eastern Australia to (1) determine the species using these structures and their frequency of crossing, (2) determine the number and demographic characteristics of individuals crossing, and (3) use the rate of crossing by individuals to infer the types of movement that occurred. Methods We used motion-triggered cameras to monitor five canopy bridges and 15 glider pole arrays installed at 13 sites along the Hume Freeway. The five canopy bridges were also monitored with passive integrated transponder (PIT)-tag readers to identify the rate of use by individuals. Key results Five species of arboreal marsupial were detected using canopy bridges and glider poles at 11 sites. Our analysis suggested that increasing the number and the distance between poles in a glider pole array reduced the rate of use by squirrel gliders. The PIT tag and camera footage revealed that the structures were used by adult males, adult females and juveniles, suggesting that all demographic groups are capable of using canopy bridges and glider poles. At two canopy bridges, multiple squirrel gliders and common brushtail possums crossed more than once per night. Conclusions Given that previous studies have shown that the freeway is a barrier to movement, and that many of the species detected crossing are subject to road mortality, we conclude that canopy bridges and glider poles benefit arboreal marsupials by providing safe access to resources that would otherwise be inaccessible. Implications Although the factors influencing crossing rate require further study, our analysis suggests that glider pole arrays with fewer poles placed closer together are likely to be more successful for squirrel gliders. The individual identification methods applied here offer insights that are not possible from measuring the rate of use alone and should be adopted in future monitoring studies.
23
Xiong, Gang, Jian Jiang, Yi Tao Wu e Jun Chen. "The Hydrodynamic Analysis of Hybrid-Driven Underwater Glider". Advanced Materials Research 694-697 (maggio 2013): 577–81. http://dx.doi.org/10.4028/www.scientific.net/amr.694-697.577.
Abstract (sommario):
The hybrid-driven underwater glider (HUG) is a new kind of underwater vehicle; it combines the best features of autonomous underwater vehicles and underwater gliders, and can be used as important platforms for marine environment observation and ocean resource exploration. It’s difficult to get the drag coefficient of HUG through theoretical formula. In this paper, we use analysis software Fluent to analyze the HUG with different attack-angle and velocities, get the lift 、 drag coefficient and lift-drag ratio, and determine the biggest lift-drag ratio of HUG in the attack- angle of 6 degrees.
24
von Oppeln-Bronikowski, Nicolai, Brad de Young, Dariia Atamanchuk e Douglas Wallace. "Glider-based observations of CO<sub>2</sub> in the Labrador Sea". Ocean Science 17, n. 1 (4 gennaio 2021): 1–16. http://dx.doi.org/10.5194/os-17-1-2021.
Abstract (sommario):
Abstract. Ocean gliders can provide high-spatial- and temporal-resolution data and target specific ocean regions at a low cost compared to ship-based measurements. An important gap, however, given the need for carbon measurements, is the lack of capable sensors for glider-based CO2 measurements. We need to develop robust methods to evaluate novel CO2 sensors for gliders. Here we present results from testing the performance of a novel CO2 optode sensor (Atamanchuk et al., 2014), deployed on a Slocum glider, in the Labrador Sea and on the Newfoundland Shelf. This paper (1) investigates the performance of the CO2 optode on two glider deployments, (2) demonstrates the utility of using the autonomous SeaCycler profiler mooring (Send et al., 2013; Atamanchuk et al., 2020) to improve in situ sensor data, and (3) presents data from moored and mobile platforms to resolve fine scales of temporal and spatial variability of O2 and pCO2 in the Labrador Sea. The Aanderaa CO2 optode is an early prototype sensor that has not undergone rigorous testing on a glider but is compact and uses little power. Our analysis shows that the sensor suffers from instability and slow response times (τ95>100 s), affected by different behavior when profiling through small (<3 ∘C) vs. large (>10 ∘C) changes in temperature over similar time intervals. We compare the glider and SeaCycler O2 and CO2 observations and estimate the glider data uncertainty as ± 6.14 and ± 44.01 µatm, respectively. From the Labrador Sea mission, we point to short timescales (<7 d) and distance (<15 km) scales as important drivers of change in this region.
25
Arwie, Dzikra, e Rahmat Aryandi. "Identifikasi Antibodi Spesifik Toxoplasma gondii Pada Wanita Di Komunitas Pecinta Sugar Glider Indonesia (Kpsgi) Kota Makassar". Jurnal Kesehatan Panrita Husada 4, n. 1 (15 marzo 2019): 30–48. http://dx.doi.org/10.37362/jkph.v4i1.169.
Abstract (sommario):
This research is motivated by quite a lot of public interest in maintaining pet animals such as sugar gliders but the negative effects of these animals can cause zoonotic diseases such as toxoplasmosis caused by the parasite Toxoplasma gondii. However, the presence of Toxoplasma gondii specific antibodies against sugar glider lovers is not known with certainty. This study aims to identify specific Toxoplasma gondii antibodies in women in the Makassar Sugar Glider Indonesia (KPSGI) Lovers community. The study was a laboratory observation with qualitative analysis techniques with the research subjects being women in the sugar glider (KPSGI) lover community in Makassar. Of the 10 samples taken by purposive sampling technique, 40% of female samples were obtained in the body with Toxoplasma gondii specific antibodies.
26
Dzikra Arwie e Rahmat Aryandi. "IDENTIFIKASI ANTIBODI SPESIFIK Toxoplasma gondii PADA WANITA DI KOMUNITAS PECINTA SUGAR GLIDER INDONESIA (KPSGI) KOTA MAKASSAR". Jurnal Kesehatan Panrita Husada 4, n. 1 (17 settembre 2019): 30–48. http://dx.doi.org/10.37362/jkph.v4i1.180.
Abstract (sommario):
This research is motivated by quite a lot of public interest in maintaining pet animals such as sugar gliders but the negative effects of these animals can cause zoonotic diseases such as toxoplasmosis caused by the parasite Toxoplasma gondii. However, the presence of Toxoplasma gondii specific antibodies against sugar glider lovers is not known with certainty. This study aims to identify specific Toxoplasma gondii antibodies in women in the Makassar Sugar Glider Indonesia (KPSGI) Lovers community. The study was a laboratory observation with qualitative analysis techniques with the research subjects being women in the sugar glider (KPSGI) lover community in Makassar. Of the 10 samples taken by purposive sampling technique, 40% of female samples were obtained in the body with Toxoplasma gondii specific antibodies.
27
Lee, Jung-Han, Sung-Hyub Ko, Seom-Kyu Jung e Jong-Wu Hyeon. "Tertiary Waves Measured during 2017 Pohang Earthquake Using an Underwater Glider". Applied Sciences 9, n. 18 (14 settembre 2019): 3860. http://dx.doi.org/10.3390/app9183860.
Abstract (sommario):
An underwater glider equipped with a hydrophone observed the acoustic sounds of an earthquake that occurred on 15 November 2017 05:29:32 (UTC) in the Pohang area. The underwater glider observed the earthquake sounds after 19 s (05:29:51) at approximately 140 km from the Pohang epicenter. In order to distinguish the earthquake sound from the glider’s operation noise, the noise sources and Sound Pressure Level (SPL) of the underwater glider were analyzed and measured at laboratory tank and sea. The earthquake acoustic signal was distinguished from glider’s self-noises of fin, pumped Conductivity-Temperature-Depth profiler (CTD) and altimeter which exist over 100 Hz. The dominant frequencies of the earthquake acoustic signals due to the earthquake were 10 Hz. Frequencies at which the spectra had dropped 60 dB were 50 Hz. By analysis of time correlation with seismic waves detected by five seismic land stations and the earthquake acoustic signal, it is clearly shown that the seismic waves converted to Tertiary waves and then detected by the underwater glider. The results allow constraining the acoustic sound level of the earthquake and suggest that the glider provides an effective platform for enhancing the earth seismic observation systems and monitoring natural and anthropogenic ocean sounds.
28
Hong, Xue Wu, Jian Zhao, Si Zhuo Zhao, Ming Yu e Yan Yang. "Research on Dynamic Characteristics of Glider Hydrofoil by Finite Element Models Analysis". Key Engineering Materials 693 (maggio 2016): 182–86. http://dx.doi.org/10.4028/www.scientific.net/kem.693.182.
Abstract (sommario):
The underwater glider is a new type of autonomous underwater vehicle driven by buoyancy. The glider hydrofoil is the key driving element of the glider, it works under complex alternative load and determines the safety of navigation of the underwater glider. This paper takes the hydrofoil as the research object, a finite element model of hydrofoil has been established and the dynamic load of hydrofoil has been calculated. Finite element model analysis was conducted to the glider hydrofoil in free and restrained states, and the preceding few orders natural frequency of the glider hydrofoil and the corresponding vibration model and the vibration amplitude in the conditions were conducted respectively. The dangerous area of the glider hydrofoil was found out, which could provide data for optimal dynamic design and dynamic modification of hydrofoil.
29
Sang, Hongqiang, Jin Zhang, Xiujun Sun, Can Li, Lei Wang e Liwei Wang. "Optimal Design and Dynamic Analysis of Hydrofoil Mechanism of Wave Glider". Journal of Marine Science and Engineering 10, n. 3 (4 marzo 2022): 367. http://dx.doi.org/10.3390/jmse10030367.
Abstract (sommario):
A wave glider can convert vertical wave motion into its forward propulsion. There are many factors affecting the propulsion performance of a wave glider. The swing amplitude of hydrofoil can affect the efficiency of hydrofoil to capture wave energy, and the pull direction of an umbilical cable can affect the transmission efficiency of wave energy. In this paper, an optimized hydrofoil mechanism with a self-adjusting lower limit (SALL) was proposed by analyzing the un- synchronized movement between the submerged glider and the surface float. This mechanism was able to transfer the movement of umbilical cable to the hydrofoil swing mechanism through the linkage to control the lower limit of hydrofoil swing (maximum swing angle of hydrofoil in a counterclockwise direction). Firstly, the user-defined function (UDF) was written to control the motion of hydrofoil in the fluid domain. The lower limit swing angle and the heave direction of the hydrofoil were both set in the UDF, and the forward thrust generated by the passive swing of the hydrofoil in the fluid domain was able to be obtained by the simulation. Secondly, the prototype was designed by introducing a parallelogram mechanism on a conventional submerged glider, and a wave simulation test platform was built to verify the propulsive performance of the prototype. The results showed that, in comparison with the conventional submerged glider, the forward thrust of the SALL submerged glider was able to be improved by 1.50%, 17.78%, 7.42%, and 20.70% under the stiffness coefficients of torsion spring set to K = 2, K = 4, K = 6, and K = 8 in the simulation experiment, respectively. The forward thrust of the SALL submerged glider was able to be elevated by 9.99% with torsion spring K = 8 in the tank experiment. The advantage of the SALL mechanism was verified by comparing the results of the simulation and the tank experiment. Finally, the feasibility of the SALL submerged glider was verified in actual sea conditions by a sea trial.
30
Ahmad, U. N., e Y. Xing. "A 2D model for the study of equilibrium glide paths of UiS Subsea Freight-Glider". IOP Conference Series: Materials Science and Engineering 1201, n. 1 (1 novembre 2021): 012022. http://dx.doi.org/10.1088/1757-899x/1201/1/012022.
Abstract (sommario):
Abstract A planar mathematical model for the analysis of equilibrium glide paths of the UiS subsea freight-glider (USFG) is presented. The model is developed using Simscape Multibody in MATLAB/Simulink to study the ever-changing dynamics of the glider. Motion along the heave and pitch direction is regulated by two separate PID controllers. Controllers are tuned for the optimal bandwidth and phase margin to provide the system with ideal gains which satisfy the system requirements. A wide-ranging sensitivity investigation is carried out on the USFG by changing the two key variables, pump flow rate and ballast fraction. The results reflect the advantages of using higher flow capacity and ballast fraction, which should be preferred according to the application, provided if there are no space and weight restrictions. Finally, different glide paths were simulated to observe that, controller gains obtained from the linear model can be improved to acquire better performance in terms of robustness and stability of the system.
31
Wang, Xiuyuan, Zongyu Chang, Zhongqiang Zheng, Jiakun Zhang, Zhanxia Feng e Guiqiao Lu. "Analysis and Selection of Deployment Methods for a Wave Glider System". Journal of Marine Science and Engineering 8, n. 7 (17 luglio 2020): 529. http://dx.doi.org/10.3390/jmse8070529.
Abstract (sommario):
A wave glider is a novel unmanned marine vehicle which can convert marine energy into kinetic energy. In practice, it is crucial for the wave glider system to deploy into the ocean environment efficiently and safely. Hence, the present work establishes the wave glider motion equations to analyze the deployment method. Firstly, the wave glider model is simplified in the vertical plane and the cable model is defined as mass nodes connected with a massless spring. Then, two typical deployment methods (Method 1 and Method 2) are proposed based on the multibody dynamic method, and the numerical simulation model is established to investigate the kinematic performance of two deployment methods. Lastly, the dynamic characteristic analysis is conducted to select the determined deployment method. We explain the practical advantages of Method 1, which would provide the reference for the deployment method selection.
32
Ball, Tina, Eddie Adams e Ross L. Goldingay. "Diet of the squirrel glider in a fragmented landscape near Mackay, central Queensland". Australian Journal of Zoology 57, n. 5 (2009): 295. http://dx.doi.org/10.1071/zo08095.
Abstract (sommario):
We investigated the diet of the squirrel glider (Petaurus norfolcensis) from within a highly fragmented landscape in the northern (tropical) part of its geographic range where information was absent. We analysed 86 faecal samples of 53 gliders from 11 locations and obtained 97 observations of 10 gliders feeding at two locations. Pollen of Eucalyptus/Corymbia was present in 70% and Melaleuca in 20% of faecal samples. Indicators of sap feeding were present in 44% of samples and seeds were present in 14% of samples. Invertebrates, mostly moth larvae, were present in 54% of samples. Observations of gliders feeding revealed that the main food types were invertebrates (36% of observations), nectar and pollen (27% of observations) and sap (26% of observations) of five tree species. Differences in the use of the major food types revealed by the two methods of diet analysis partly reflect site-based differences. Qualitatively, the diet was similar to that described in southern Australia, with confirmation that sap may be important at some locations. Our results reveal the contribution that different tree species make to the diet, which should be used to guide habitat restoration for the squirrel glider in this fragmented landscape.
33
Jiang, Yong-Min, Stan Dosso, Luigi Troiano e Alain Maguer. "Passive acoustic glider for marine acoustic environment characterization". Journal of the Acoustical Society of America 154, n. 4_supplement (1 ottobre 2023): A338. http://dx.doi.org/10.1121/10.0023724.
Abstract (sommario):
Acoustic payload-equipped underwater gliders have great potential for assessing the marine soundscape (oceanic acoustic environment), including characterizing properties of the sound field, of acoustic sources, and of the marine environment (water column and seabed). This talk presents observations and analysis of passive acoustic recordings carried out by gliders during the 2017 Seabed Characterization Experiment (SBCEX17). Two Teledyne Webb Research Slocum gliders equipped with omni-directional hydrophones were deployed as virtual acoustic moorings in 72 m deep water on the New England Mud Patch for time periods of ∼6 days for one glider and ∼3 days for the other. Acoustic recordings collected by the gliders captured the marine soundscape, including natural ambient noise, marine-life sounds, ship noise, and acoustic signals transmitted by the SBCEX17 participants. The acoustic environment in the water column is characterized in terms of the acoustic power spectral density as a function of time, depth, and frequency. As an example of the use of passive acoustic gliders for environmental characterization, Bayesian geoacoustic inversion for seabed properties is presented, making use of recordings of controlled sources associated with SBCEX17. [Work supported by the Office of Naval Research.]
34
P. Kavanagh, Rodney, e Rodney P. Kavanagh. "Effects of variable-intensity logging and the influence of habitat variables on the distribution of the Greater Glider Petauroides volans in montane forest, southeastern New South Wales". Pacific Conservation Biology 6, n. 1 (2000): 18. http://dx.doi.org/10.1071/pc000018.
Abstract (sommario):
Populations of arboreal marsupials were assessed in forests before and after logging at different levels of logging intensity to determine the sensitivity of these species to habitat disturbance. The logging treatments imposed were unlogged controls and two intensities of integrated logging for sawlogs and woodchips. The mean basal area of trees retained in logged blocks ranged from 83% to 35% of pre-logging levels. The objective of the study was to develop better methods for managing arboreal marsupials within the wood production forests of southeastern New South Wales. Seven species of arboreal marsupials were recorded during the study, but the Greater Glider Petauroides volans was the only species recorded in sufficient numbers for analysis (86% of all records). No significant differences were observed between the treatments in counts of the Greater Glider before and after logging. However, given the observed trend and an a priori expectation of a decline in numbers of this species following intensive logging, a one-tailed statistical test was applied which resulted in a significant difference at P = 0.08 for the contrast between the unlogged controls and the most intensively logged treatment. The existence of a threshold in logging intensity within the range of 21 % to 39% retention of tree basal area, below which numbers of the Greater Glider suffer a marked decline, was inferred on the basis of comparisons with the results of other studies. Factors other than logging were important in determining the distribution of the Greater Glider. Elevation, in particular, was a significant environmental variable, with Greater Gliders more likely to occur in forests above 845 m a.s.1. The presence and absence of particular tree species also influenced the distribution of the Greater Glider. Forests containing Manna Gum E. viminalis and Mountain Gum E. dalrympleana were highly preferred compared to forests with a high proportion of E. obliqua. The presence of E. cypellocarpa appeared to improve the quality of habitat for the Greater Glider in forests dominated by E. obliqua. This study has shown that Greater Glider populations can be maintained at or near pre-logging levels when at least 40% of the original tree basal area is retained thoughout logged areas and when the usual practice of retaining unlogged forest in riparian strips is applied.
35
Jia, Li Juan, Xuan Ming Zhang, Zhan Feng Qi, Yu Feng Qin e Xiu Jun Sun. "Hydrodynamic Analysis of Submarine of the Wave Glider". Advanced Materials Research 834-836 (ottobre 2013): 1505–11. http://dx.doi.org/10.4028/www.scientific.net/amr.834-836.1505.
Abstract (sommario):
Wave glider harvests the abundant ocean wave energy for long term ocean cruising due to its particular two-part architecture. Its submerged part named glider converts vertical fluctuation of waves to horizontally forward propulsion. Because of the uncertainty of the ocean condition and irregularity of its wave motion, the design parameters of the submerged glider vary in a confined range in the state of art design models. In order to indicate the hydrodynamic characteristics and summarize the dynamic law of the submerged glider with different design parameters, this paper concentrates on three critical design details: profile of the wings, interval space of the arrayed multiple flapping wings and maximum rotating angle of wings, and performs the corresponding CFD analysis. Finally, we conclude that the lift curve of NACA0006 and plate profile is almost the same with small waves at sea, but NACA0006 profile can generate much larger forward lift than the plate profile with seawater velocity up to 0.5m/s; Decreasing space of intermittent causes more obvious decrement of forward lift while space of intermittent overpasses the inflection point at 20cm; With the decrement of the maximum rotating angle, the forward lift occurs to take a sharp decline if the angle strides the inflection point.
36
De León-Gordillo, Dagoberto, Noé Amir Rodríguez-Olivares, Leonardo Barriga-Rodríguez, José Luis Sánchez-Gaytán, Jorge Alberto Soto-Cajiga, Guillermo Ronquillo-Lomelí e Tomás Salgado-Jiménez. "Development of a Datalogger for Submarine Glider: Integration of Fault-Tolerant Software Layers". Journal of Marine Science and Engineering 9, n. 12 (30 novembre 2021): 1352. http://dx.doi.org/10.3390/jmse9121352.
Abstract (sommario):
Submarine gliders are specialized systems used in applications such as environmental monitoring of marine fauna, in the oil industry, among others. The glider launch and capture is a costly process that requires substantial technological and human resources, so the orderly and error-free storage of data is of fundamental importance due to the subsequent analysis. The amount of information being obtained from the seabed is increasing, this leads to the need to develop robust and low-cost ad-hocsystems for this type of application. The challenge is the integration of the different software layers in the storage system because the monitored variables must be ordered according to different glider operations such as calibration data update and navigation. Additionally, to avoid data corruption in the memory chip, error control coding must be used. The goal of this paper is to present a novel design of different layers of software integrated into a datalogger: reception, error control, and storage logic for the different glider operations. The design of the datalogger is based on a NAND flash memory chip and an MSP430 microcontroller. To correct bit-flipping errors, a BCH code that corrects 4 errors for every 255 bits is implemented into the microcontroller. The design and evaluation are performed for different glider operations, and for different lengths and correction capabilities of the BCH module. A test to calculate the storage time has been carried out. This test shows that in the case of 256 bytes per sample, at 30 samples per minute, and 1 GB of storage capacity, it is possible to collect data from the glider sensors for 84 days. The results obtained show that our device is a useful option for storing underwater sensor data due to its real-time storage, power consumption, small size, easy integration, and its reliability, where the bit error rate BER is of 2.4 ×10−11.
37
Guo, Liming, Jing Liu, Baowei Song, Guang Pan e Yujun Liu. "Vibration Analysis and Suppression Methods of the Wing of an Underwater Glider". International Journal of Acoustics and Vibration 28, n. 3 (30 settembre 2023): 249–57. http://dx.doi.org/10.20855/ijav.2023.28.31928.
Abstract (sommario):
Vibration analysis and suppression methods are widely studied in mechanical systems. In this study, rubber damping materials were employed to enhance the vibration suppression performance of the wing of an underwater glider. A finite element model was established to analyze the vibration characteristics of the wing. The excitation characteristics of the actuator were determined by experimental methods. The wet mode shapes and corresponding frequencies of the wing of the underwater glider were investigated. The vibration suppression performance of rubber damping materials with different thickness and hardness was discussed. The optimal parameters of the rubber pads on various positions were provided to minimize the excitations from the actuator. This paper provides valuable insights for developing vibration suppression techniques for the wings of an underwater glider.
38
Retnowati, Nurcahyani Dewi, Buyung Junaidin e Engelbertus Rande. "GLIDER MODEL FLYING DYNAMICS SIMULATION EAGE-X ON LONGITUDINAL MATRA". Vortex 3, n. 1 (15 gennaio 2022): 59. http://dx.doi.org/10.28989/vortex.v3i1.1165.
Abstract (sommario):
The Glider Eagle-X aircraft is an unmanned aircraft which is expected to fly with a height of 7 meters above the ground in Yogyakarta (120 m above sea level) with a flying speed of 10 m/s. In order for the Eagle-X glider to fly stably, it is necessary to analyze the flight stability of the Eagle-X glider model. Therefore, in this study, the analysis phase of static stability and dynamic response of disturbances in the longitudinal dimension was carried out. This can be useful for students so that they can better understand the analysis of static stability and dynamic response of disturbances in the longitudinal dimension. The results of the analysis show that the flight dynamics is a value of CM-α < 0 indicating the plane is statically longitudinal and the initial response of the graph is getting smaller which indicates the plane's motion is dynamically stable. The output of the stability analysis of the flying dynamics of the Eagle-X glider model is in the form of a graph. The simulation of the flying dynamics of the Eagle-X glider in the expected longitudinal dimension is shown by the aircraft movement following the graph from the results of the stability analysis which is used as the path of the Eagle-X glider model.
39
Niu, Wen-dong, Shu-xin Wang, Yan-hui Wang, Yang Song e Ya-qiang Zhu. "Stability analysis of hybrid-driven underwater glider". China Ocean Engineering 31, n. 5 (ottobre 2017): 528–38. http://dx.doi.org/10.1007/s13344-017-0061-y.
40
Goldingay, RL, e RP Kavanagh. "Foraging behaviour and habitat use of the feathertail glider (Acrobates pygmaeus) at Waratah Creek, New South Wales". Wildlife Research 22, n. 4 (1995): 457. http://dx.doi.org/10.1071/wr9950457.
Abstract (sommario):
Observations were made of the foraging behaviour of the feathertail glider (Acrobates pygmaeus) at Waratah Creek in south-eastern New South Wales (NSW). Gliders were observed on 164 occasions, including 42 observations of feeding, 41 observations of moving along a substrate and 68 observations of gliding to a tree, an understorey plant or to the ground. On the remaining occasions, gliders were lost from view before any information was recorded. Most (91%) feeding observations occurred in live eucalypts. When feeding in eucalypts, 61% of observations were of gliders searching under loose shedding bark and 32% were of gliders engaged in foliage gleaning. Foraging amongst loose bark is suggested to represent feeding on honeydew and arthropods while foliage gleaning is indicative of gliders engaged in feeding on manna, honeydew, lerps and arthropods. Nectar feeding was uncommon and only 3% of trees in which gliders were observed were flowering. In contrast, 42% of these trees showed signs of recent bark shed. Two observations were of gliders foraging on the ground, suggesting that arthropods may also be captured there. Comparison of the frequency of use of different tree species with the abundance of those species showed a highly significant preference for E. fastigata, while other species were used in proportion to their abundance. Analysis also showed that gliders used trees in the smallest of three size classes (<40 cm diameter at breast height) less often than expected on the basis of the abundance of these trees. Overall, gliders used the six different habitat types in the study area in proportion to their abundance but showed significant seasonal differences in the use of these habitats. These results permit consideration of the management requirements of the feathertail glider in the timber production forests of NSW. It is concluded that the requirements of this species are catered for by existing management prescriptions.
41
Rayaprolu, Venkata Shashank Shankar, e R. Vijayakumar. "Sensitivity Analysis of the Turning Motion of an Underwater Glider on the Viscous Hydrodynamic Coefficients". Defence Science Journal 71, n. 5 (2 settembre 2021): 709–17. http://dx.doi.org/10.14429/dsj.71.16905.
Abstract (sommario):
Autonomous underwater gliders (AUG) are a class of underwater vehicles that move using a buoyancy engine and forces from wings. Gliders execute turning motion with the help of a rudder or an internal roll control mechanism and the trajectory of the turn is a spiral. This paper analyses the sensitivity of the characteristics of spiral manoeuvre on the hydrodynamic coefficients of the glider. Based on the dynamics model of a gliding fish whose turn is enabled by a rudder, the effect of hydrodynamic coefficients of the hull and the rudder on the spiral motion are quantified. Local sensitivity analysis is undertaken using the indirect method. The order of importance of hydrodynamic coefficients is evaluated. It is observed that the spiral path parameters are most sensitive to the side force created by the rudder and the effect of the drag coefficient is predominant to that of the lift coefficients. This study will aid in quantifying the effect of change of geometry on the manoeuvrability of AUGs.
42
Su, Dong Hai, Yu Zhang, Ying Shi e Kuo Yang. "Research on Driving Mechanism and Movement Principle of Underwater Glider". Advanced Materials Research 433-440 (gennaio 2012): 6825–31. http://dx.doi.org/10.4028/www.scientific.net/amr.433-440.6825.
Abstract (sommario):
In this paper, firstly, the organization structure and working principle of gliders are introduced. Secondly, the buoyancy driven principle of gliders as well as the composition of buoyancy drive system is given. Thirdly, the stationary movement state is analyzed and the law of motion about the steady gliding as well as steady spiral rotation in vertical space are given and the principles, control method of vertical steady glide as well as spiral steady rotation in space are also given, which provides an important theoretical basis with the movement control of underwater gliders. Finally, the vehicle’s underwater experiment was completed. The results of experiment proved that the theoretical analysis is correct and also verified that the design of vehicle is rational, which could meet the requirement of control.
43
Oh, Soram, Ju-Hyo Park, Hyun-Jung Kim, Hye-Jeong Kim, Eurok Shim, Jee-Yeon Woo, Hiran Perinpanayagam, Kyung-Kyu Choi e Seok Woo Chang. "Torsional Fracture Resistance of Niti Rotary Glide Path Files under Flexural Stress". Applied Sciences 12, n. 12 (18 giugno 2022): 6214. http://dx.doi.org/10.3390/app12126214.
Abstract (sommario):
This study aimed to evaluate the effects of flexural stress on the torsional fracture resistance of NiTi glide path files. PathFile #16/02, RaCe #15/04, RaCe Evo #15/04, HyFlex EDM #15/03, TruNatomy Glider #17/02, and V Taper 2H #17/04 were examined by scanning electron microscopy (SEM) (n = 3/brand) and subjected to differential scanning calorimetry (n = 2/brand). Torsional fracture resistance testing was performed in straight (ISO 3630-1) and flexural modes (n = 15/brand/mode). Flexural mode testing involved instruments rotating within a stainless-steel artificial double-curved canal. Ultimate strength and distortion angle until failure were recorded, and fractured instruments were examined by SEM. Statistical analyses involved independent sample t-test and one-way analysis of variance with Games–Howell pots hoc test. Austenitic transformation- finishing temperatures of heat-treated files were above body temperature. For RaCe Evo, HyFlex EDM, TruNatomy Glider, and V Taper 2H, the flexural mode resulted in a significantly higher distortion angle compared to the straight mode (p < 0.05). The maximum torque of RaCe Evo, HyFlex EDM increased with the flexural stress (p < 0.05). V taper 2H showed the highest distortion angle and ultimate strength. SEM showed typical patterns of torsional fracture for all tested files. The flexural stress positively affected distortion angle of heat-treated NiTi glide path files.
44
Kang, J. I., S. K. Jeoung, J. Y. Oh, H. S. Choi, Y. H. Kim, J. Y. Kim, S. H. Yu e H. K. Cho. "An analysis of carbon fiber hull structure of a new underwater glider". International Journal of Modern Physics B 32, n. 19 (18 luglio 2018): 1840065. http://dx.doi.org/10.1142/s0217979218400659.
Abstract (sommario):
In this research, hull structure of Ray-type Underwater Glider (RUG) that could be a next generation unmanned vehicle was studied. RUG is capable of long-term operation at higher speeds than conventional cylindrical underwater gliders due to its ray shaped body composed of dual buoyancy engine. For long-term operation, it is necessary to develop a lightweight control housing and battery case. For this reason, the carbon fiber container was used to be lighter and stronger than duralumin used in the past. Through the stress and buckling analysis, it was shown that the container was able to withstand the pressure of 200 m which is the target water depth with the safety ratio of about 1.8 times. Using a carbon composite material, the mechanical strength can be maintained while reducing the weight of the pressure vessel by more than 40% compared with the high tensile aluminum material.
45
Jiang, Feng, Muping Zhou, Feng Zhou e Zhentao Hu. "Glider Network Observation Unraveling A Cyclonic Eddy in the Northwestern Pacific Subtropical Countercurrent". Journal of Physics: Conference Series 2486, n. 1 (1 maggio 2023): 012009. http://dx.doi.org/10.1088/1742-6596/2486/1/012009.
Abstract (sommario):
Abstract The North Pacific Subtropical Countercurrent (STCC) is a zonal current consisting of a weak eastward current near the surface and a westward current (north equatorial current, NEC) below. Previous studies have proved that this region is an extremely active region of the North Pacific eddy. The activity of mesoscale eddy in this region can directly or indirectly affect the periodic variations of the Kuroshio and the Chinese coastal waters. In order to study the structure of mesoscale eddies in this region and their impact on the upper ocean, five Petrel-II underwater gliders were conducted as a network to collect hydrographic properties from December 09 2020 to February 05, 2021. It is found that a cyclonic eddy passed through the glider network from east to west during the observation period, and the glider grid almost covers the whole eddy. The radius, amplitude and propagation velocity of the eddy were analyzed. The underwater gliders were equipped with CTD sensors, collected about 1200 full thermohaline profiles. The observation results indicated that the cyclonic eddy can influence over 400 m in the vertical, which caused the isotherm rising up to 40 m. Analysis based on satellite sea surface temperature (SST) and sea level anomaly (SLA) data suggest that the cyclonic eddy is probably locally generated.
46
Ma, Yunlong, Guang Pan, Qiaogao Huang e Jinglu Li. "Research on Hydrodynamic Characteristics of Blended Wing Body Underwater Glider with Rudder". Xibei Gongye Daxue Xuebao/Journal of Northwestern Polytechnical University 38, n. 1 (febbraio 2020): 24–30. http://dx.doi.org/10.1051/jnwpu/20203810024.
Abstract (sommario):
In order to improve the maneuverability and stability of the Blended Wing Body (BWB) underwater glider, the trailing edge rudder is integrated into its shape design in this paper. Through the numerical simulation of CFD, the variation laws of the hydraulic parameters such as lift, drag, lift-to-drag ratio with the angle of attack and rudder angle are given. Compared with the traditional underwater glider, the BWB underwater glider not only has high loading capacity, but also has a maximum lift-to-drag ratio three times that of the former, resulting in higher energy efficiency. At the same time, by adding trailing edge rudders, the maneuverability of the BWB underwater glider is improved, and the lift-to-drag ratio under the same large rudder angle is increased by more than 30% compared with the variable-wing underwater glider. Finally, through the analysis of the numerical results and the cloud image, the difference interaction extent between the rudder and the body of the BWB underwater glider and the traditional torpedo or AUV is illustrated.
47
Feng, Zhanxia, Zongyu Chang, Zhongqiang Zheng e Panfeng Wang. "Effects of Connection Type between Surface Vessel and Submersible Propeller on Motion Performance of Wave Glider". Applied Sciences 8, n. 12 (3 dicembre 2018): 2467. http://dx.doi.org/10.3390/app8122467.
Abstract (sommario):
Wave Glider is an autonomous surface vehicle that directly uses wave energy to generate forward power and has been widely used in marine survey and observation. Wave Glider is composed of surface vessel, submersible propeller and the connection structure between them. Connection types are thought to be related to the performance of Wave Glider closely. In this paper, the effects of the connection structure between the surface vessel and the submersible propeller on the motion performance of the Wave Glider are studied. Several connection types such as rigid rod, cable, multi-link chain and elastic rod are applied to connect the surface vessel and the submersible propeller. The models of connection structures are developed respectively. Among them, cable model is established with a finite number of small cylinders, which connected by spring and damping elements; multi-link chain can be seen as hinged by multiple rigid rods; elastic rod model can be looked on as several segments linked with elastic components. Considering the connection characteristics, the integrated dynamic models are established by applying multi-body dynamics software ADAMS (Automatic Dynamic Analysis of Mechanical Systems) with consideration of the hydrodynamic forces on different components of Wave Glider. The propulsion performance of the Wave Glider is calculated by using numerical method, and the simulation results showed that the difference of propulsion performance with different connection types of the Wave Glider is slightly. But serious impacts can occur on the connections of rigid rod and multi-link chain. They can lead to serious extra load on the structure of Wave Glider. From the engineering practice of Wave Glider application, the cable connection is more convenient to transport, deploy, recover and store. It is also the generous connection type for wave glider.
48
Wang, Peng, Xuehao Wang, Yanhui Wang, Wendong Niu, Shaoqiong Yang, Chao Sun e Chenyi Luo. "Dynamics Modeling and Analysis of an Underwater Glider with Dual-Eccentric Attitude Regulating Mechanism Using Dual Quaternions". Journal of Marine Science and Engineering 11, n. 1 (20 dicembre 2022): 5. http://dx.doi.org/10.3390/jmse11010005.
Abstract (sommario):
The underwater glider has difficulty accessing the complex and narrow hadal trench for observation, which is affected by its limited regulation capability of pitch angle (−45°~45°). In this study, a compact attitude regulating mechanism is proposed to extend the regulation range of pitch angle from −90°to 90° and to install it on the hadal-class underwater glider Petrel-XPLUS. Subsequently, the dynamics model of Petrel-XPLUS is established using dual quaternions to solve the “gimbal lock” problem caused by the increased pitch angle range. Within the extended pitch range, the motion modes of the glider are enriched into long-range, virtual mooring, and Lagrangian float modes for long-range, small-area, and current-following observation missions, respectively, and are analyzed using the established dynamics model. Moreover, a ballast method was used to modify the pitch angle range and initial equilibrium state of a constructed underwater glider. Finally, Petrel-XPLUS achieved a pitch angle regulation range of −90°~90° in a water pool experiment and completed three consecutive profiles in a sea trial in the Challenger Deep, Mariana Trench, with all depths over 10,000 m, of which the maximum depth was 10,619 m. The proposed mechanism and methods can also be applied to other submersibles to facilitate ocean observations.
49
Priohutomo, Kusnindar, Wibowo Harso Nugroho e Rosi Dwi Yulfani. "Strength Analysis and Assessment of Ina-TEWS Wave Glider". International Journal of Natural Science and Engineering 4, n. 3 (14 dicembre 2020): 140. http://dx.doi.org/10.23887/ijnse.v4i3.29873.
Abstract (sommario):
Indonesia as a country that often experiences tsunami disasters needs to have an early warning system against tsunami disasters. This system can use various existing technologies, one of which is the tsunami buoy system. The new tsunami buoy system does not use the natural mooring system but uses the wave glider system. This paper discusses the structural strength of the surface floater of wave glider using Eva Foam and Fiberglass material for skin and Alluminium material for frame and kell. The surface floater using 16 pieces for frame and 1 piece for keel. Enviromental loads is use in this paper like hydrodynamics load and weight load. The results from this paper is material from Eva Foam has a maximum principle stress is 12693 Pa and shear stress is 6114.6 Pa. For material from Fiberglass has maximum principle stress is 11.875 Pa and shear stress is 6076.3 Pa. Safety factor (SF) from maximum principle stress and shear stress for Eva Foams is up to 6x and SF for maximum principle and shear stress for Fiberglass is up to 26x. Conclusions for this paper is the desain for surface floater of wave glider it can be operated in the sea with draugh 0.18 m.
50
Inprasetyobudi, H., Y. Y. E. Darma, N. Rinanto, G. H. Wibowo e R. E. P. Utomo. "Design and analysis of low-cost underwater glider for shallow water". IOP Conference Series: Earth and Environmental Science 925, n. 1 (1 novembre 2021): 012055. http://dx.doi.org/10.1088/1755-1315/925/1/012055.
Abstract (sommario):
Abstract This paper aims to design a low-cost underwater glider to operate in shallow water. The proposed design was developed by manufacturing engineering software. Analysis of the hull using manufacturing engineering software and 3D computer-aided design (CAD). The analysis of hydrodynamics using computational fluid dynamics (CFD). This glider was designed to operate in shallow water, coastal, lake and river for a maximum depth of 10 m and a maximum speed of current 12,96 km/h, or 3,6 m/s. To reduce and minimize the cost to manufacture this underwater glider, the mechanics, electrical, electronics, and power source were using common tools on the market, not on demand. Based on numerical model, the hull pressure had 30,127 psi or 0,2077162 MPa for maximum depth 10 m and max speed 12,96 km/h. Maximum pressure occurs on the nose and behind the wings. This unmanned vehicle was designed to be in 9 compartments. The first compartment and 8th compartment are used for ballast tanks. The others for: mechanics of ballast system, altimeter and attitude controller, payload, battery pack, main controller part, propulsion system, and propulsor.