Location In Space Research Articles

Analysis of accidental spacecraft break-up events in cislunar space

Fragmentation events are the most common source of artificial debris in space. Such events can happen for multiple reasons, ranging from collisions with active or inactive objects to propellant tanks or battery explosions. They are an inherent part of human activities in space, regardless of the location. At the same time, the interest in the Moon and the space around it increases. Multiple planned missions want to leverage the peculiar dynamics of the Earth-Moon system to build an infrastructure likely to support human exploration of space for centuries to come. The present research puts a step forward in the direction of Space Debris Mitigation techniques for future cislunar missions. After being tuned with novel implementation techniques, the NASA Standard Break-up Model has been employed to simulate explosion events in multiple locations in cislunar space. Notably, the Circular Restricted Three-Body Problem model has been employed to generate orbits, corrected in a higher-fidelity model to generate initial conditions for long-term propagations. Moreover, multiple starting positions along each orbit have been crossed with several possible event dates, providing a broader understanding of the aftermath of explosion events. Three case studies have been considered: an EML2 southern Near Rectilinear Halo Orbit (NRHO), candidate for the Gateway station, a larger Halo orbit of the same family, and a Distant Retrograde Orbit (DRO). These locations have been chosen to characterize dynamically different trajectories used in current applications. Results provided include the number, locations, and characteristics of collision with the Moon and the Earth, together with considerations on the interactions with Earth’s protected orbital regions of Low Earth Orbit (LEO) and Geostationary Orbit (GEO). A novel analysis is also introduced to determine the immediate danger for the Gateway station in the case of such an event. This research lays the foundation to develop a cislunar Space Debris Mitigation (SDM) framework in the hopes that awareness is raised when there is still time for proper implementation of guidelines.

Evaluation of an automatic approach device to the epidural space of Beagle dogs

ObjectiveTo compare the epidural anesthesia device (EPIA), which facilitates an automatic approach to location of the epidural space, with the performance of clinicians using tactile sensation and differences in pressure when inserting an epidural needle into the epidural space of a dog. Study designProspective, crossover experiment. AnimalsA total of 14 Beagle dogs weighing 7.5 ± 2.4 kg (mean ± standard deviation). MethodsEach dog was anesthetized three times at 2 week intervals for three anesthesiologists (two experienced, one novice) to perform 14 epidural injections (seven manual and EPIA device each). The sequence of methods was assigned randomly for each anesthesiologist. The dogs were anesthetized with medetomidine (10 μg kg–1), alfaxalone (2 mg kg–1) and isoflurane and positioned in sternal recumbency with the pelvic limbs extended cranially. Epidural puncture in the manual method was determined by pop sensation, hanging drop technique and reduced injection pressure, whereas using the device a sudden decrease in reaction force on the device was detected. A C-arm identified needle placement in the epidural space, and after administration of iohexol (0.3 mL), the needle length in the epidural space was defined as the mean value measured by three radiologists. Normality was tested using the Kolmogorov–Smirnov test, and significant differences between the two methods were analyzed using an independent sample t test. ResultsIn both methods, the success rates of epidural insertion were the same at 95.2%. The length of the needle in the epidural space using the device and manual methods was 1.59 ± 0.50 and 1.68 ± 0.88 mm, respectively, with no significant difference (p = 0.718). Conclusions and clinical relevanceEPIA device was comparable to human tactile sense for an epidural needle insertion in Beagle dogs. Further research should be conducted for application of the device in clinical environments.

Detecting informal green, blue, and street physical activity spaces in the city using geotagged sports-related Twitter tweets.

Finland's natural physical environment and climate support a wide variety of informal outdoor sports, thereby motivating the population to do physical exercise in scenic environments. The vast majority of Finns enjoys outdoor recreational activities, and could thus be encouraged to post accounts of their year-round activities on social media. Our aim was to find out in what kind of areas and spaces, spatially, users are tweeting about sporting activities. We use geotagged Twitter tweets filtering for 16 sporting activity keywords in both English and Finnish. The case study was conducted in the Helsinki Metropolitan Area, Finland, with an emphasis on cross-country skiing as a sports activity when there is snow. In a secondary analysis we concentrated on the sports people were practicing in these locations when there was no snow. The location spaces are split in to three land cover types: green, blue, and street spaces. We found that approximately half of the 150 skiing-related tweets were geotagged in green spaces, and half in street spaces. This finding related to street space was attributable to a spatial scale error: when we checked the results manually we noticed that they referenced the sporting location in the green space. Hence, then over 90% of the 745 non-ski-related tweets were geotagged in a street space. We conclude that Twitter is a beneficial tool for detecting spaces used for informal physical activity. A shortcoming in current Finnish national sporting policies is that spaces for informal physical activity are not explicitly mentioned- we use the term informal with reference both to the space and to the sporting activity, whereby public spaces are used for physical activity. This new knowledge of sporting locations will help city planners and sports planners to improve informal sports facilities, which in turn will promote healthy exercise in cities.

Streaming From the Air : Enabling Drone-Sourced Video Streaming Applications on 5G Open-RAN Architectures

Enabling high data-rate uplink cellular connectivity for drones is a challenging problem, since a flying drone has a higher likelihood of having line-of-sight propagation to base stations that terrestrial UEs normally do not have line-of-sight to. This may result in uplink inter-cell interference and uplink performance degradation for the neighboring ground UEs when drones transmit at high data-rates (e.g., video streaming). We address this problem from a cellular operator's standpoint to support drone-sourced video streaming of a point of interest. We propose a low-complexity, closed-loop control system for Open-RAN architectures that jointly optimizes the drone's location in space and its transmission directionality to support video streaming and minimize its uplink interference impact on the network. We prototype and experimentally evaluate the proposed control system on a dedicated outdoor multi-cell RAN testbed, which is the first measurement campaign of its kind. Furthermore, we perform a large-scale simulation assessment of the proposed control system using the actual cell deployment topologies and cell load profiles of a major US cellular carrier. The proposed Open-RAN control scheme achieves an average 19% network capacity gain over traditional BS-constrained control solutions and satisfies the application data-rate requirements of the drone (e.g., to stream an HD video).

Linear Programming Models for Leak Detection and Localization in Water Distribution Networks

This study examined the benefits and limitations of formulating linear programming models for water distribution network leak detection and localization considering sequences of demands. First, the consistency of sensitivity matrixes for different demand magnitudes and spatially varying nodal demands was investigated to determine if different sensitivity matrixes are needed for each time step and to determine the demands to use for computing the gradient matrixes. Then several unconstrained and constrained models were developed and their detection and localization performance was evaluated for a network in Austin, Texas. To constrain the failure location in time and space, binary (zero–one) integer linear programming (BILP) was used. A set of threshold-based detection rules was applied to test for the anomalies in the time series, and they were compared for a range of realistic leak sizes. Based on the numerical results, the best optimization model was identified considering multiple detection metrics (detection effectiveness, efficiency, and localization). The best BILP model that constrains leak locations spatially and temporally outperformed the unconstrained model in detecting and locating relatively small leaks.

Comparison of median and paramedian technique of thoracic epidural anaesthesia in patients undergoing laparotomy under combined general and epidural anaesthesia - A prospective observational study.

Most studies have found that lumbar epidural catheterisation is technically easier with a paramedian than median approach. There is scant literature comparing the two approaches to the epidural space in the mid-thoracic spine. This study aims to compare the median versus paramedian approaches in the location of epidural space in the T7-9 region in patients undergoing laparotomy under combined general and epidural anaesthesia. A prospective observational study was conducted after ethical approval and written informed consent on 70 patients undergoing major abdominal surgery. The patients received epidural analgesia either through a median or paramedian approach (Group M, n = 35 and Group P, n = 35). The primary objective was the incidence of successful epidural catheter placement in the first attempt. The secondary objectives were the overall success rate, the requirement of change of intervertebral space, approach or operator and complications associated with the procedure. Sixty-seven patients were analysed. Epidural catheter was placed successfully in the first attempt in 40% of patients in Group M and 78.1% in Group P (P = 0.003). The overall success rate was 74.3% in Group M and 87.5% in Group P (P = 0.223). The number of attempts in Group M was more (one attempt 14, two 6, three 5 and four 1) as compared to Group P (one 25, two 2, three 1 and four 0) (P = 0.014). The incidence of complications was comparable between the groups. Epidural catheter insertion was technically easier in paramedian as compared to the median approach in T7-9 thoracic region with no difference in complications.

Multi-objective optimization approach for Inverse Kinematics of redundant manipulator for welding applications

This article presents an optimization-based approach for determining the Inverse Kinematics (IK) of redundant robot manipulators for industrial welding applications. Nine degrees of freedom (DOF) kinematic configuration of a robot manipulator with one prismatic and eight revolute joints has been modelled to improve maneuverability in a welding environment. To perform welding operations at desired task space locations (TSLs), the IK are to be determined. The IK problem is solved using a constrained multi-objective optimization technique with the objective of a reachability manipulator with minimal positional and orientational errors. An obstacle avoidance algorithm is also implemented to avoid collisions during welding operations. IK Simulations of the redundant manipulator in different welding applications were performed in a MATLAB environment. The obtained results shows that the welding manipulator reached desired locations successfully and this approach is adaptable for various shapes of weld joints.

A Study on the Summer Microclimate Environment of Public Space and Pedestrian Commercial Streets in Regions with Hot Summers and Cold Winters

Pedestrian commercial streets are an important part of a city. However, the open outdoor street is easily affected by the external climate, and a poor microclimate environment can indirectly affect the volume of visitors to the commercial street. This paper takes pedestrian commercial streets in regions with hot summers and cold winters as the research object in order to obtain reasonable prototypes of street space. Adopting the experimental method of controlling variables, microclimate simulation analysis is conducted on different street flow lines, various locations of open space, and the different greening arrangements of typical street spaces. This paper also proposes design strategies for improving the microclimate environment, such as reserving ventilation passages in the dominant wind direction, setting up air buffer areas to increase the “wind storage” effect, building an open space in the upwind direction to increase the “wind absorption” effect, preventing planar greening space from hindering airflow in streets with poor ventilation, and establishing planar green space in the upwind direction to increase the coverage of the cooling effect of plants. In this paper, comfort in the outdoor microclimate comfort is taken into consideration in commercial street design, aiming to achieve the revitalization of commercial streets through “micro renovation” and provide some reference for the future design of commercial streets.

Understanding the encoding of object locations in small-scale spaces during free exploration using eye tracking

Navigation is instrumental to daily life and is often used to encode and locate objects, such as keys in one's house. Yet, little is known about how navigation works in more ecologically valid situations such as finding objects within a room. Specifically, it is not clear how vision vs. body movements contribute differentially to spatial memory in such small-scale spaces. In the current study, participants encoded object locations by viewing them while standing (stationary condition) or by additionally being guided by the experimenter while blindfolded (walking condition) after viewing the objects. They then retrieved the objects from the same or different viewpoint, creating a 2 × 2 within subject design. We simultaneously recorded participant eye movements throughout the experiment using mobile eye tracking. The results showed no statistically significant differences among our four conditions (stationary, same viewpoint as encoding; stationary, different viewpoint; walking, same viewpoint; walking, different viewpoint), suggesting that in a small real-world space, vision may be sufficient to remember object locations. Eye tracking analyses revealed that object locations were better remembered next to landmarks and that participants encoded items on one wall together, suggesting the use of local wall coordinates rather than global room coordinates. A multivariate regression analysis revealed that the only significant predictor of object placement accuracy was average looking time. These results suggest that vision may be sufficient for encoding object locations in a small-scale environment and that such memories may be formed largely locally rather than globally.

Multiagent Manuvering with the Use of Reinforcement Learning

This paper presents an approach for defining, solving, and implementing dynamic cooperative maneuver problems in autonomous driving applications. The formulation of these problems considers a set of cooperating cars as part of a multiagent system. A reinforcement learning technique is applied to find a suboptimal policy. The key role in the presented approach is a multiagent maneuvering environment that allows for the simulation of car-like agents within an obstacle-constrained space. Each of the agents is tasked with reaching an individual goal, defined as a specific location in space. The policy is determined during the reinforcement learning process to reach a predetermined goal position for each of the simulated cars. In the experiments, three road scenarios—zipper, bottleneck, and crossroads—were used. The trained policy has been successful in solving the cooperation problem in all scenarios and the positive effects of applying shared rewards between agents have been presented and studied. The results obtained in this work provide a window of opportunity for various automotive applications.

Краевой эффект сосновых древостоев северной тайги

The studies are carried out in pine stands situated on the forest boundaries, which are in between the open space locations and forest growth areas. The investigations were made on the territory of the Kholmogorskiy and Primorskiy districts in the Arkhangelsk region. The purpose of the research is to identify the characteristics of meteorological factors at different distances from the edge of phytocenosis as well as their influence on the undergrowth and ground vegetation in the ecotone zone. For this purpose, the vegetation, which grew on the transects at different distances from the edge of the phytocenosis, is described in layers. The transects were positioned perpendicular to the forest boundary. The following parameters were described and measured, such as undergrowth, ground vegetation, luminance, air temperature, wind speed, air humidity. The taxation of the stand was accomplished by using relascopic circular platforms. It is found that luminance, air temperature, and wind speed naturally decrease with distance from the edge of the phytocenosis deeper into the forest. The decrease in luminance can be revealed to 8 m, temperature to 8–15 m, wind speed to 30 m. However, air humidity increases up to 8 m. A correlation between meteorological factors and the distance from the edge of the phytocenosis is determined. The distribution of the undergrowth according to the edges of phytocenosis has a consistent pattern. The undergrowth of heliophytes of pine, birch, and aspen is most abundant at the edge of phytocenoses, and their numbers decrease with distance from the edge. The undergrowth of sciophytes either increases or its quantity does not change. Such distributions are confirmed by correlation analysis. The resulting figures are rated as significant or high. They are reliable at the significance level of 0.05. The number of plants in the grass-shrub tier decreases with the distance deep into the forest. Any define conclusion can’t be made regarding the moss-lichen tier. In general, it can be concluded that the size of the ecotone zone in terms of meteorological factors and indicators of vegetation is 12–14 m. For citation: Feklistov P.A., Sobolev A.N., Babich N.A., Sungurova N.R., Melekhov V.I., Bolotov I.N. Edge Effect in Pine Stands in the Northern Taiga. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 2, pp. 26–37. (In Russ.). https://doi.org/10.37482/0536-1036-2023-2-26-37

Modeling and Simulation for a Five DOF Robotic Arm Manipulator

Nowadays, service robots are used in a large number of applications in the service industry. With the booming service industry in third world countries, service robots are expected to be used in a wider range of applications, so it is of great importance to conduct research on service robots. This paper develops the model of a kinematic models for a 5 DOF robotic arm that used in service industry in SolidWorks. The robotic arm’s mathematical model is predicated on Denavit-Hartemberg (DH) method, which determine the robot joints angle vector. The procedure aims at describing the forward and inverse kinematic analysis, and finally determine the end effector’s position and orientation through the corresponding joints angle related to the coordinate system (CS), in order to control the robotic arm to reach the designated location in space. A simulation model of the robotic arm was built using the Matlab Robotics Toolbox to verify the correctness of forward and inverse kinematics, which also can simplify the calculation and analysis.

Evaluation of the BET and GAB models for interpretation of soil water isotherms: A molecular simulation study

Mathematical characterization of soil water isotherm (SWI) plays a significant role in modeling various processes in soils and estimating the soil properties, and the Brunauer-Emmet-Teller (BET) and Guggenheim-Anderson-de Boer (GAB) models are most widely used. Each model uses the amount of adsorbed gas in the monolayer on the surface for area estimates. Although these two models are widely used with soils, studies on the applicabilities of the SWIs estimated with the two models and the reliabilities of the derived monolayer contents are noticeably lacking. This work presents detailed evaluations of the two models and the resulting SWIs and determines whether these provide meaningful monolayer contents. The SWIs for four representative soils were generated with Grand Canonical Monte Carlo (GCMC) simulations, and the data were evaluated along with a wealth of information on the physical states of the adsorbed water molecules. The results showed that the GAB model was much superior to the BET model in terms of fitting the SWIs. A series of analyses validated the soundness of the monolayer contents determined, including analyses of the layer thickness, the area occupied by the water monolayer, and the orientations of the water molecules. The molecular simulation also revealed the very different effects of the surface hydroxyls and cations in adsorption by considering the densities, space locations, and orientations of the adsorbed water. This work provides crucial information for rational application of the BET and GAB models to SWIs.

LSOS: An FG Position Method Based on Group Phase Ranging Ambiguity Estimation of BeiDou Pseudolite

Due to the influence of indoor space environments, the carrier phase information obtained by the BeiDou pseudo-satellite often has the issue of cycle slips, which makes the user unable to carry out high-precision positioning. Aiming at the problem of ambiguity resolution (AR) and location in large-scale occluded space (LSOS), a factor graph (FG) position method based on group phase ranging ambiguity estimation of BeiDou pseudolite is proposed. Firstly, by introducing the principle of group phase period quantization and utilizing the multi-frequency characteristic of the BeiDou pseudo-satellite, the carrier phase propagation ambiguity of the BeiDou pseudo-satellite can be estimated quickly. On this basis, by introducing the shuffled frog leading algorithm (SFLA) assisted factor graph optimization location estimation method, the BeiDou pseudo-satellite positioning process in LSOS is realized. The experimental results show that the proposed method can solve the problem of fast estimation of ranging ambiguity of BeiDou pseudolite in LSOS, and the ranging accuracy can be improved to two wavelength ranges. In the further location experiment, it is found that the algorithm can not only guarantee the real-time location output but also improve the location precision to sub-meter level under the multi-frequency combination; the optimal location test precision is 9 cm, the maximum positioning error is 50 cm. This method successfully solves the problem wherein the BeiDou pseudo-satellite cannot provide real-time, continuous, and high-precision positioning in LSOS.

Optimizing urban green space patterns to improve spatial equity using location-allocation model: A case study in Wuhan

Green space allocation aims to support the UNs sustainable development goals (SDGs) and to mitigate the conflicts between supply and demand. Previous studies have shown that the uneven distribution of populations and natural locations of green space results in environmental inequity. However, there is still a lack of knowledge on strategies for reducing mismatches of supply and demand by optimizing spatial patterns in highly dense cities. Developed urbanized areas are featured in fewer spaces for greening. In this study, we set three scenarios for coordinating the provision and demand of urban green spaces at a block scale. Taking the main city of Wuhan as an example, we apply the location-allocation model in order to identify potential sites for new green spaces. Then, the simulations of the three scenarios are used to depict various development strategies by evaluating the improvement of green equity. Our results show that the levels of green space accessibility are lower on the west side of the city center, while relatively higher on the east side, due to abundant natural resources. The Gini coefficient is 0.715, indicating unequal access for citizens to green space. Increasing green areas could enhance green equity, and the most effective way to allocate new increments is based on the accessibility. For developed cities, blocks with lower accessibility should be given priority when increasing green areas; doing so could offset the shortage of large green areas and reduce green inequity within daily walking distances. Optimal green space planning of small and functional parks near communities has the potential to meet higher recreational demands in densely populated areas.

A Pattern of Public Open Space Utilization in Tondo I Permanent Resettlement Residential Area (HUNTAP) as Evacuation Space

Learning from the disaster in Palu on September 28, 2018, disaster management in residential areas needs to be facilitated, such as a disaster evacuation or gathering point. This study tries to see the other side of the function of public space as an evacuation shelter in a settlement, with the study case of Huntap I Tondo. This study aims to formulate a pattern of public open space as an evacuation space in Permanent Residential (Huntap) I Tondo. The method is descriptive with field observation of data collection techniques and questionnaires. The stages of the research are 1) conducting spatial analysis to map the location of public open spaces and 2) using the behavioral mapping method and describing it to reveal the spatial pattern created from the reciprocal relationship between humans and space. 3) Distributing questionnaires to determine perceptions and preferences of public open spaces as evacuation spaces. The results obtained the pattern and factors of public open space as an evacuation space in the Huntap I Tondo area are influenced by, (1) the physical aspect of the availability of the nearest public space in the form of environmental roads and open spaces in residential areas. (2) Non-physical aspects include survivors’ and refugees’ social interactions.

A Learned Map for Places and Concepts in the Human Medial Temporal Lobe.

Distinct lines of research in both humans and animals point to a specific role of the hippocampus in both spatial and episodic memory function. The discovery of concept cells in the hippocampus and surrounding medial temporal lobe (MTL) regions suggests that the MTL maps physical and semantic spaces with a similar neural architecture. Here, we studied the emergence of such maps using MTL microwire recordings from 20 patients (9 female, 11 male) navigating a virtual environment featuring salient landmarks with established semantic meaning. We present several key findings. The array of local field potentials in the MTL contains sufficient information for above-chance decoding of subjects' instantaneous location in the environment. Closer examination revealed that as subjects gain experience with the environment the field potentials come to represent both the subjects' locations in virtual space and in high-dimensional semantic space. Similarly, we observe a learning effect on temporal sequence coding. Over time, field potentials come to represent future locations, even after controlling for spatial proximity. This predictive coding of future states, more so than the strength of spatial representations per se, is linked to variability in subjects' navigation performance. Our results thus support the conceptualization of the MTL as a memory space, representing both spatial- and nonspatial information to plan future actions and predict their outcomes.SIGNIFICANCE STATEMENT Using rare microwire recordings, we studied the representation of spatial, semantic, and temporal information in the human MTL. Our findings demonstrate that subjects acquire a cognitive map that simultaneously represents the spatial and semantic relations between landmarks. We further show that the same learned representation is used to predict future states, implicating MTL cell assemblies as the building blocks of prospective memory functions.

FUNCTIONAL QUALITIES OF LVIV’S NEWEST CHRISTIAN CHURCHES

The article consides the problems of Lviv’s newest sacred architectural buildings, namely their functional qualities. It is proven that among the main reasons why religious people rarely attend liturgies can be a lack of time or a general reluctance to visit the church, giving priority to other matters. The following principles of the designing of church educational institutions are given: denominationalism and ecumenism; multi-education; sacredness; worldliness; inclusiveness; flexibility and mobility; traditionalism and modernity. The main functional zones are distinguished, which include the entrance zone, sanctuary, entertainment and recreation, educational, dining, residential, commercial, administrative, technical, household, exhibition and auxiliary groups of objects. The necessity of searching for new ways and means of spreading spiritual knowledge in society is indicated. It requires new methods and approaches in the design of institutions of religious activity. Special attention is paid to the needs of people with disabilities. Public spaces are divided into functional and cultural and educational spaces. Types of location of public spaces in churches are described, they are: part of the floor, in a specially built building, with a specially decorated entrance, under the open sky, part of the building. The topic of public space in temples is considered. It is noted that the building of the spiritual retreat center, which combines various social functions, is designed in such a way as to ensure the comfort of visitors and the smooth operation of all functional processes. The internal organization of space plays an important role in this. The interior is the final addition to create an artistic image and overall harmonious composition. In the study, the functions of sacred architecture are determined: (commercial function, social/public function, religious function, etc.). It is determined that the church, as a building, is historically something more than a religious building. It is proposed to design the temple as multifunctional and to develop it not only as a religious building, but also as a public area. Recommendations on the architectural solution of sacred buildings are given, an overview of individual examples of modern sacred architecture in Lviv is given. The functional properties of modern churches in Lviv are analyzed.

Optimal sizing of solar-wind based hybrid energy system using modified dragonfly algorithm for an institution

Globally, most solar and wind power systems can produce power cheaper than fossil fuel-powered systems under certain circumstances according to the international renewable energy agency (IRENA). Despite that, the penetration rate of renewable energy has slowed down recently due to its non-availability and reliability in providing an uninterruptible power supply. A hybrid renewable energy system (HRES) with the conventional grid to counter the intermittency challenges without battery storage is a way forward for a greener solution. In this paper, unutilized rooftop space and underutilized potential locations of an educational institution are customized for renewable Solar-Wind power generation together with the conventional grid for effective and cost-optimal power solutions. A modified dragonfly algorithm (MDA) was adopted for mathematical modeling to reduce the power systems' net present value (NPV) over its lifespan. The model reckons various scenarios and found that the HRES with grid interaction is the best case to significantly improve the reliability economically. The result is encouraging to promote HRES in potential institutions to boost the growth of renewable energy, economically to achieve the net zero emission goal of IRENA by 2050.

TriHorn-Net: A model for accurate depth-based 3D hand pose estimation

3D hand pose estimation methods have made significant progress recently. However, estimation accuracy is often far from sufficient for specific real-world applications, and thus there is significant room for improvement. This paper proposes TriHorn-Net, a novel model that uses specific innovations to improve hand pose estimation accuracy on depth images. The first innovation is decomposition of the 3D hand pose estimation into the estimation of 2D joint locations in the depth image space (UV), and the estimation of their corresponding depths aided by two complementary attention maps. This decomposition prevents depth estimation, which is a more difficult task, from interfering with the UV estimations at both the prediction and feature levels. The second innovation is PixDropout, which is, to the best of our knowledge, the first appearance-based data augmentation method for hand depth images. Experimental results demonstrate that the proposed model outperforms the state-of-the-art methods on three public benchmark datasets, achieving 5.73 mm, 7.13 mm, and 7.68 mm on the ICVL, MSRA, and NYU datasets, respectively. The proposed model achieves this performance with a relatively fast average inference speed of 9.25 ms per frame on an NVIDIA 1080Ti GPU, which, as discussed in the paper, places the proposed model among the fastest-performing 3D hand pose estimation models. Our implementation is available at https://github.com/mrezaei92/TriHorn-Net.