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Journal articles on the topic 'Landmark Estimation'

Author: Grafiati

Published: 6 September 2023

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1

Sakai, Atsushi, Teppei Saitoh, and Yoji Kuroda. "Robust Landmark Estimation and Unscented Particle Sampling for SLAM in Dynamic Outdoor Environment." Journal of Robotics and Mechatronics 22, no. 2 (2010): 140–49. http://dx.doi.org/10.20965/jrm.2010.p0140.

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In this paper, we propose a set of techniques for accurate and practical Simultaneous Localization And Mapping (SLAM) in dynamic outdoor environments. The techniques are categorized into Landmark estimation and Unscented particle sampling. Landmark estimation features stable feature detection and data management for estimating landmarks accurately, robustly, and at a low-calculation cost. The stable feature detection removes dynamic objects and sensor noise with scan subtraction, detects feature points sparsely and evenly, and sets data association parameters with landmark density. The data ma

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Liu, Shengli, Xiaowen Zhu, Zewei Cao, and Gang Wang. "Deep 1D Landmark Representation Learning for Space Target Pose Estimation." Remote Sensing 14, no. 16 (2022): 4035. http://dx.doi.org/10.3390/rs14164035.

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Monocular vision-based pose estimation for known uncooperative space targets plays an increasingly important role in on-orbit operations. The existing state-of-the-art methods of space target pose estimation build the 2D-3D correspondences to recover the space target pose, where space target landmark regression is a key component of the methods. The 2D heatmap representation is the dominant descriptor in landmark regression. However, its quantization error grows dramatically under low-resolution input conditions, and extra post-processing is usually needed to compute the accurate 2D pixel coor

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Fujii, Hajime, Yoshinobu Ando, Takashi Yoshimi, and Makoto Mizukawa. "Shape Recognition of Metallic Landmark and its Application to Self-Position Estimation for Mobile Robot." Journal of Robotics and Mechatronics 22, no. 6 (2010): 718–25. http://dx.doi.org/10.20965/jrm.2010.p0718.

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This paper proposes a method of improving selfposition estimation accuracy with metallic landmarks for mobile robots. Many methods of the past selfposition estimation researches have used GPS, laserrange scanners, and CCD cameras, but have been unable to obtain landmark information correctly due to environmental factors. Metallic landmarks are useful in environments where conventional sensors do not work well. Self-position estimation accuracy is thus increased by combining metallic landmark information with that from other equipment.

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Floreskul, Volodymyr, Konstantin Tretyakov, and Marlon Dumas. "Memory-Efficient Fast Shortest Path Estimation in Large Social Networks." Proceedings of the International AAAI Conference on Web and Social Media 8, no. 1 (2014): 91–100. http://dx.doi.org/10.1609/icwsm.v8i1.14532.

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As the sizes of contemporary social networks surpass billions of users, so grows the need for fast graph algorithms to analyze them. A particularly important basic operation is the computation of shortest paths between nodes. Classical exact algorithms for this problem are prohibitively slow on large graphs, which motivates the development of approximate methods. Of those, landmark-based methods have been actively studied in recent years. Landmark-based estimation methods start by picking a fixed set of landmark nodes, precomputing the distance from each node in the graph to each landmark, and

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Fong, Li Wei, Pi Ching Lou, and Ke Jia Tang. "Vehicle Kinematic State Estimation Using Passive Sensor Fusion Approach." Applied Mechanics and Materials 271-272 (December 2012): 1709–12. http://dx.doi.org/10.4028/www.scientific.net/amm.271-272.1709.

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The main issue addressed here is that of estimating the kinematic state components of a vehicle in autonomous navigation using landmark angle-only measurements from an onboard passive sensor. The estimates of the absolute position and velocity of the vehicle are provided by a hybrid coordinate fusion filter. The hierarchical architecture of the filter which consists of a group of local processors and a global processor is developed for improving estimation accuracy. In each local processor, an extended Kalman filter uses hybrid information from the reference Cartesian coordinate system and the

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Mohd Shah, Hairol Nizam, Zalina Kamis, Azhar Ahmad, Mohd Rizuan Baharon, Muhd Akmal Noor Rajikon, and Kang Hui Hwa. "Vision Based Position Control for Vertical Take-off and Landing (VTOL) Using One Singular Landmark." Modern Applied Science 13, no. 9 (2019): 33. http://dx.doi.org/10.5539/mas.v13n9p33.

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This project presents a vision based position control for Vertical Take-off and Landing (VTOL) to recognise a singular landmark for landing and take-off. Position control can provide safe flight and an accurate navigation. The circle landmark which used is an artificial landmark at known locations in an environment. Initially, a camera mounted on VTOL facing downward detecting landmarks in environments. A single circle used as landmark and VTOL will be control the position to reach the landmark. The images from the down-looking camera provided vision data to estimates position of VTOL from lan

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Chen, Yao Chang, Ta Ming Shih, and Chung Ho Wang. "Stereo Vision Specific Observation Model for EKF-Based SLAM." Applied Mechanics and Materials 373-375 (August 2013): 238–41. http://dx.doi.org/10.4028/www.scientific.net/amm.373-375.238.

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This work addresses a new probabilistic observation model for a stereo simultaneous localization and mapping (SLAM) system within the standard Extended-Kalman filter (EKF) framework. The observation modal was derived by using the inverse depth parameterization as the landmark modal, and contributes to both bearing and range information into the EKF estimation. In this way the inherently non-linear problem cause by the projection equations is resolved and real depth uncertainty distribution of landmarks features can be accurately estimated. The system was demonstrated with real-world outdoor da

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Hsu, Chen-Chien, Cheng-Kai Yang, Yi-Hsing Chien, Yin-Tien Wang, Wei-Yen Wang, and Chiang-Heng Chien. "Computationally efficient algorithm for vision-based simultaneous localization and mapping of mobile robots." Engineering Computations 34, no. 4 (2017): 1217–39. http://dx.doi.org/10.1108/ec-05-2015-0123.

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Purpose FastSLAM is a popular method to solve the problem of simultaneous localization and mapping (SLAM). However, when the number of landmarks present in real environments increases, there are excessive comparisons of the measurement with all the existing landmarks in each particle. As a result, the execution speed will be too slow to achieve the objective of real-time navigation. Thus, this paper aims to improve the computational efficiency and estimation accuracy of conventional SLAM algorithms. Design/methodology/approach As an attempt to solve this problem, this paper presents a computat

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D’Amelio, Richard, and Thomas J. Dunn. "Revisiting the Santa Barbara sense of direction scale, mental rotations, and gender differences in spatial orientation." PsyPag Quarterly 1, no. 115 (2020): 7–10. http://dx.doi.org/10.53841/bpspag.2020.1.115.7.

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Angular direction estimation to landmarks of varying distance in the physical environment was utilised to investigate the ecological validity of the Santa Barbara sense of direction scale (SBSOD). Two- and three-dimensional MR measures were included to enable further the scale applicability. Results showed a moderate correlation between SBSOD and angular deviation from landmarks in the immediate landscape, but not with local or distant landmarks. Moreover, the findings suggest that skills which underlie three-dimensional MR better relate to pointing accuracy (PA) of distant landmarks and the c

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Chen, Haiwen, Jin Chen, Zhuohuai Guan, Yaoming Li, Kai Cheng, and Zhihong Cui. "Stereovision-Based Ego-Motion Estimation for Combine Harvesters." Sensors 22, no. 17 (2022): 6394. http://dx.doi.org/10.3390/s22176394.

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Ego-motion estimation is a foundational capability for autonomous combine harvesters, supporting high-level functions such as navigation and harvesting. This paper presents a novel approach for estimating the motion of a combine harvester from a sequence of stereo images. The proposed method starts with tracking a set of 3D landmarks which are triangulated from stereo-matched features. Six Degree of Freedom (DoF) ego motion is obtained by minimizing the reprojection error of those landmarks on the current frame. Then, local bundle adjustment is performed to refine structure (i.e., landmark pos

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Elli, Stefano, Giacomo Bellani, Luigi Cannizzo, et al. "Reliability of cutaneous landmarks for the catheter length assessment during peripherally inserted central catheter insertion: A retrospective observational study." Journal of Vascular Access 21, no. 6 (2020): 917–22. http://dx.doi.org/10.1177/1129729820911225.

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Introduction: Peripherally inserted central catheters are very common devices for short, medium and long-term therapies. Their performance is strictly dependent on the correct tip location, at the junction between the upper caval vein and the right atrium. It is very important to obtain an estimated measure of the catheter, in order to reach the cavo-atrial junction and optimize the catheter length. Estimated measures are often obtained using cutaneous landmarks. Objective: Evaluate the reliability of cutaneous landmark-based length estimation during catheter insertion. Identify any patient’s

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Yun, Hye Sun, Chang Min Hyun, Seong Hyeon Baek, Sang-Hwy Lee, and Jin Keun Seo. "A semi-supervised learning approach for automated 3D cephalometric landmark identification using computed tomography." PLOS ONE 17, no. 9 (2022): e0275114. http://dx.doi.org/10.1371/journal.pone.0275114.

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Identification of 3D cephalometric landmarks that serve as proxy to the shape of human skull is the fundamental step in cephalometric analysis. Since manual landmarking from 3D computed tomography (CT) images is a cumbersome task even for the trained experts, automatic 3D landmark detection system is in a great need. Recently, automatic landmarking of 2D cephalograms using deep learning (DL) has achieved great success, but 3D landmarking for more than 80 landmarks has not yet reached a satisfactory level, because of the factors hindering machine learning such as the high dimensionality of the

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Liu, Shuang, Hongli Xu, Yang Lin, and Lei Gao. "Visual Navigation for Recovering an AUV by Another AUV in Shallow Water." Sensors 19, no. 8 (2019): 1889. http://dx.doi.org/10.3390/s19081889.

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Autonomous underwater vehicles (AUVs) play very important roles in underwater missions. However, the reliability of the automated recovery of AUVs has still not been well addressed. We propose a vision-based framework for automatically recovering an AUV by another AUV in shallow water. The proposed framework contains a detection phase for the robust detection of underwater landmarks mounted on the docking station in shallow water and a pose-estimation phase for estimating the pose between AUVs and underwater landmarks. We propose a Laplacian-of-Gaussian-based coarse-to-fine blockwise (LCB) met

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Lee, Yang Sun, Jang Woo Park, and Leonard Barolli. "A Localization Algorithm Based on AOA for Ad-Hoc Sensor Networks." Mobile Information Systems 8, no. 1 (2012): 61–72. http://dx.doi.org/10.1155/2012/986327.

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Knowledge of positions of sensor nodes in Wireless Sensor Networks (WSNs) will make possible many applications such as asset monitoring, object tracking and routing. In WSNs, the errors may happen in the measurement of distances and angles between pairs of nodes in WSN and these errors will be propagated to different nodes, the estimation of positions of sensor nodes can be difficult and have huge errors. In this paper, we will propose localization algorithm based on both distance and angle to landmark. So, we introduce a method of incident angle to landmark and the algorithm to exchange physi

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Allen, Robert C., Daniel P. McDonald, and Michael J. Singer. "Landmark Direction and Distance Estimation in Large Scale Virtual Environments." Proceedings of the Human Factors and Ergonomics Society Annual Meeting 41, no. 2 (1997): 1213–17. http://dx.doi.org/10.1177/1071181397041002109.

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The current paper describes our classification of errors participants made when estimating direction and distances in a large scale (2000 m × 2000 m) Virtual Environment (VE). Two VE configuration groups (Low or High Interactivity) traversed a 400 m route through one of two Virtual Terrain's (Distinctive or Non-Distinctive or Terrain 1 and 2, respectively) in 100 m increments. The High VE group used a treadmill to move through the VE with head tracked visual displays; the Low VE group used a joystick for movement and visual display control. Results indicate that as experience within either ter

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Keelson, Benyameen, Luca Buzzatti, Jakub Ceranka, et al. "Automated Motion Analysis of Bony Joint Structures from Dynamic Computer Tomography Images: A Multi-Atlas Approach." Diagnostics 11, no. 11 (2021): 2062. http://dx.doi.org/10.3390/diagnostics11112062.

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Dynamic computer tomography (CT) is an emerging modality to analyze in-vivo joint kinematics at the bone level, but it requires manual bone segmentation and, in some instances, landmark identification. The objective of this study is to present an automated workflow for the assessment of three-dimensional in vivo joint kinematics from dynamic musculoskeletal CT images. The proposed method relies on a multi-atlas, multi-label segmentation and landmark propagation framework to extract bony structures and detect anatomical landmarks on the CT dataset. The segmented structures serve as regions of i

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Micheler, Carina M., Jan J. Lang, Nikolas J. Wilhelm, et al. "Scaling Methods of the Pelvis without Distortion for the Analysis of Bone Defects." Current Directions in Biomedical Engineering 8, no. 2 (2022): 797–800. http://dx.doi.org/10.1515/cdbme-2022-1203.

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Abstract For the development of new types of hip implants for acetabulum revision, it is beneficial to analyse the acetabular defects of the indication group in advance. In order to be able to specially compare the bone defects with each other, a normalisation and accompanying scaling of the pelvis is necessary. Uniform scaling is required so that the bone structures are not distorted. In the following study, three scaling methods based on the minimal bounding box and sphere principle are compared with a method using 14 landmarks on the pelvis.The landmark method is applied to determine the tr

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Gdoura, Ahmed, Markus Degünther, Birgit Lorenz, and Alexander Effland. "Combining CNNs and Markov-like Models for Facial Landmark Detection with Spatial Consistency Estimates." Journal of Imaging 9, no. 5 (2023): 104. http://dx.doi.org/10.3390/jimaging9050104.

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The accurate localization of facial landmarks is essential for several tasks, including face recognition, head pose estimation, facial region extraction, and emotion detection. Although the number of required landmarks is task-specific, models are typically trained on all available landmarks in the datasets, limiting efficiency. Furthermore, model performance is strongly influenced by scale-dependent local appearance information around landmarks and the global shape information generated by them. To account for this, we propose a lightweight hybrid model for facial landmark detection designed

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Ye, Jianghao, Ying Cui, Xiang Pan, Herong Zheng, Dongyan Guo, and Yanan Ren. "An improved boundary-aware face alignment using stacked dense U-Nets." International Journal of Advanced Robotic Systems 17, no. 4 (2020): 172988142094090. http://dx.doi.org/10.1177/1729881420940900.

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Facial landmark localization is still a challenge task in the unconstrained environment with influences of significant variation conditions such as facial pose, shape, expression, illumination, and occlusions. In this work, we present an improved boundary-aware face alignment method by using stacked dense U-Nets. The proposed method consists of two stages: a boundary heatmap estimation stage to learn the facial boundary lines and a facial landmark localization stage to predict the final face alignment result. With the constraint of boundary lines, facial landmarks are unified as a whole facial

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Maltzahn, Niklas, Rune Hoff, Odd O. Aalen, Ingrid S. Mehlum, Hein Putter, and Jon Michael Gran. "A hybrid landmark Aalen-Johansen estimator for transition probabilities in partially non-Markov multi-state models." Lifetime Data Analysis 27, no. 4 (2021): 737–60. http://dx.doi.org/10.1007/s10985-021-09534-4.

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AbstractMulti-state models are increasingly being used to model complex epidemiological and clinical outcomes over time. It is common to assume that the models are Markov, but the assumption can often be unrealistic. The Markov assumption is seldomly checked and violations can lead to biased estimation of many parameters of interest. This is a well known problem for the standard Aalen-Johansen estimator of transition probabilities and several alternative estimators, not relying on the Markov assumption, have been suggested. A particularly simple approach known as landmarking have resulted in t

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Rowell, N., M. N. Dunstan, S. M. Parkes, J. Gil-Fernández, I. Huertas, and S. Salehi. "Autonomous visual recognition of known surface landmarks for optical navigation around asteroids." Aeronautical Journal 119, no. 1220 (2015): 1193–222. http://dx.doi.org/10.1017/s0001924000011210.

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AbstractWe present an autonomous visual landmark recognition and pose estimation algorithm designed for use in navigation of spacecraft around small asteroids. Landmarks are selected as generic points on the asteroid surface that produce strong Harris corners in an image under a wide range in viewing and illumination conditions; no particular type of morphological feature is required. The set of landmarks is triangulated to obtain a tightly fitting mesh representing an optimal low resolution model of the natural asteroid shape, which is used onboard to determine the visibility of each landmark

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Wen, Zhihua, and Michael Rabinovich. "Network distance estimation with dynamic landmark triangles." ACM SIGMETRICS Performance Evaluation Review 36, no. 1 (2008): 433–34. http://dx.doi.org/10.1145/1384529.1375507.

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Lee, Jyun-Cheng, Chih-Chun Chen, Chang-Te Shen, and Ying-Chih Lai. "Landmark-Based Scale Estimation and Correction of Visual Inertial Odometry for VTOL UAVs in a GPS-Denied Environment." Sensors 22, no. 24 (2022): 9654. http://dx.doi.org/10.3390/s22249654.

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With the rapid development of technology, unmanned aerial vehicles (UAVs) have become more popular and are applied in many areas. However, there are some environments where the Global Positioning System (GPS) is unavailable or has the problem of GPS signal outages, such as indoor and bridge inspections. Visual inertial odometry (VIO) is a popular research solution for non-GPS navigation. However, VIO has problems of scale errors and long-term drift. This study proposes a method to correct the position errors of VIO without the help of GPS information for vertical takeoff and landing (VTOL) UAV

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Liu, Pin-Ling, Chien-Chi Chang, Jia-Hua Lin, and Yoshiyuki Kobayashi. "Simple benchmarking method for determining the accuracy of depth cameras in body landmark location estimation: Static upright posture as a measurement example." PLOS ONE 16, no. 7 (2021): e0254814. http://dx.doi.org/10.1371/journal.pone.0254814.

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To evaluate the postures in ergonomics applications, studies have proposed the use of low-cost, marker-less, and portable depth camera-based motion tracking systems (DCMTSs) as a potential alternative to conventional marker-based motion tracking systems (MMTSs). However, a simple but systematic method for examining the estimation errors of various DCMTSs is lacking. This paper proposes a benchmarking method for assessing the estimation accuracy of depth cameras for full-body landmark location estimation. A novel alignment board was fabricated to align the coordinate systems of the DCMTSs and M

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Karkasina, Dafni, Margarita Kokla, and Eleni Tomai. "Investigating drivers’ geospatial abilities in unfamiliar environments." AGILE: GIScience Series 2 (June 4, 2021): 1–10. http://dx.doi.org/10.5194/agile-giss-2-3-2021.

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Abstract. The prominence of landmarks in aiding pedestrian navigation has been highlighted in various studies; people rely strongly on visual landmarks, especially when navigating in unfamiliar environments. The paper describes the design and implementation of a study for assessing drivers’ spatial abilities, when navigating in an unfamiliar environment. Two types of route directions based on references to either landmarks or street names were given to two groups of participants. Three geospatial learning tasks are used to evaluate these abilities: map sketching, distance, and direction estima

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Koh, Kyoung C., Jae S. Kim, and Hyung S. Cho. "A position estimation system for mobile robots using a monocular image of a 3-D landmark." Robotica 12, no. 5 (1994): 431–41. http://dx.doi.org/10.1017/s0263574700017987.

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SUMMARYThis paper presents an absolute position estimation system for a mobile robot moving on a flat surface. In this system, a 3-D landmark with four coplanar points and a non-coplanar point is utilized to improve the accuracy of position estimation and to guide the robot during navigation. Applying theoretical analysis, we investigate the image sensitivity of the proposed 3-D landmark compared with the conventional 2-D landmark. In the camera calibration stage of the experiments, we employ a neural network as a computational tool. The neural network is trained from a set of learning data co

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Senejohnny, Danial, and Mehrzad Namvar. "A predictor-based attitude and position estimation for rigid bodies moving in planar space by using delayed landmark measurements." Robotica 35, no. 6 (2016): 1415–30. http://dx.doi.org/10.1017/s0263574716000187.

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SUMMARYThis paper proposes a globally and exponentially convergent predictive observer for attitude and position estimation based on landmark measurements and velocity (angular and linear) readings. It is assumed that landmark measurements are available with time-delay. The maximum value of the sensor delay under which the estimation error converges to zero is calculated. Synthesis of the observer is based on a representation of rigid-body kinematics and sensor delay, formulated via ordinary and partial differential equations (ODE-PDE). Observability condition specifies necessary and sufficien

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Yoshinaga, Tsukasa, Kazunori Nozaki, Osamu Kondo, and Akiyoshi Iida. "Estimation of sibilant groove formation and sound generation from early hominin jawbones." JASA Express Letters 2, no. 4 (2022): 045203. http://dx.doi.org/10.1121/10.0010209.

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The speech production capability of sibilant fricatives of early hominin was assessed by interpolating the modern human vocal tract to an Australopithecine specimen based on the jawbone landmarks, and then simulating the airflow and sound generation. The landmark interpolation demonstrates the possibility to form the sibilant groove in the anterior part of the oral tract, and results of the aeroacoustic simulation indicate that the early hominins had the potential to produce the fricative broadband noise with a constant supply of airflow to the oral cavity, although the ancestor's tongue defor

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Liu, Xin Ying, and Ping Ping Liu. "LSD Based Pose and Position Estimation for UAV Landing." Applied Mechanics and Materials 631-632 (September 2014): 602–5. http://dx.doi.org/10.4028/www.scientific.net/amm.631-632.602.

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Currently, there has been growing interest in unmanned aerial vehicle (UAV) during the landing. With the widespread use of the UAVs, a more precise estimation on pose and position in the process of landing is required to support the higher-level applications. In this paper, the estimation of pose and position based on the line segment detection (LSD) is proposed. By applying a vision camera, a landmark is detected using the effective LSD algorithm. Then a line-based vision model is built to calculate the pose and position of the UAV. Experimental results show that the state solutions of the pr

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Sayadi, Mehrab, Najaf Zare, Armin Attar, and Seyyed Mohammad Taghi Ayatollahi. "Improved Landmark Dynamic Prediction Model to Assess Cardiovascular Disease Risk in On-Treatment Blood Pressure Patients: A Simulation Study and Post Hoc Analysis on SPRINT Data." BioMed Research International 2020 (April 23, 2020): 1–16. http://dx.doi.org/10.1155/2020/2905167.

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Landmark model (LM) is a dynamic prediction model that uses a longitudinal biomarker in time-to-event data to make prognosis prediction. This study was designed to improve this model and to apply it to assess the cardiovascular risk in on-treatment blood pressure patients. A frailty parameter was used in LM, landmark frailty model (LFM), to account the frailty of the patients and measure the correlation between different landmarks. The proposed model was compared with LM in different scenarios respecting data missing status, sample size (100, 200, and 400), landmarks (6, 12, 24, and 48), and f

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Korolov, Volodimir, Stepan Savchuk, Olha Korolova, Ihor Milkovich, and Yaroslav Zaec. "Mathematical Model for Errors Estimation of Object’s Location Parameters Determination Using Flying Platform." Baltic Surveying 10 (June 1, 2019): 26–30. http://dx.doi.org/10.22616/j.balticsurveying.2019.003.

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Some tasks require identification of landmarks in districts beyond the reach of existing optical observation facilities. The accuracy of their determination significantly affects the effectiveness of the use necessary equipment during the task. In the paper an algorithm to determine the object parameters using a flying platform is offered. An observation point is installed which is equipped with a navigation system to solve this task. This ensures its orientation and positioning. From the observation point an aerial observation point is displayed. It is suggested to use a flying platform. The

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Putter, Hein, and Cristian Spitoni. "Non-parametric estimation of transition probabilities in non-Markov multi-state models: The landmark Aalen–Johansen estimator." Statistical Methods in Medical Research 27, no. 7 (2016): 2081–92. http://dx.doi.org/10.1177/0962280216674497.

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The topic non-parametric estimation of transition probabilities in non-Markov multi-state models has seen a remarkable surge of activity recently. Two recent papers have used the idea of subsampling in this context. The first paper, by de Uña Álvarez and Meira-Machado, uses a procedure based on (differences between) Kaplan–Meier estimators derived from a subset of the data consisting of all subjects observed to be in the given state at the given time. The second, by Titman, derived estimators of transition probabilities that are consistent in general non-Markov multi-state models. Here, we sho

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Song, Meijia, Hong Liu, Wei Shi, and Xia Li. "PCLoss: Fashion Landmark Estimation with Position Constraint Loss." Pattern Recognition 118 (October 2021): 108028. http://dx.doi.org/10.1016/j.patcog.2021.108028.

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Xie, Zhifeng, Zhipeng Zhou, Zhaosheng Wang, Huiming Ding, and Lizhuang Ma. "Multi-Scale Spatial Feature-Guided Cloth Landmark Estimation." Journal of Computer-Aided Design & Computer Graphics 34, no. 11 (2022): 1763–71. http://dx.doi.org/10.3724/sp.j.1089.2022.19189.

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Chen, Yuzhong, Yang Yu, and Guolong Chen. "Shortest distance estimation in large scale graphs." Engineering Computations 31, no. 8 (2014): 1635–47. http://dx.doi.org/10.1108/ec-11-2012-0286.

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Purpose – Shortest distance query between a pair of nodes in a graph is a classical problem with a wide variety of applications. Exact methods for this problem are infeasible for large-scale graphs such as social networks with hundreds of millions of users and links due to their high complexity of time and space. The purpose of this paper is to propose a novel landmark selection strategy which can estimate the shortest distances in large-scale graphs and clarify the efficiency and accuracy of the proposed strategy in comparison with currently used strategies. Design/methodology/approach – Diff

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Oh, Chahyun, Boohwi Hong, Yumin Jo, et al. "A retrospective comparison for prediction of optimal length of right subclavian vein catheterization in infants: landmark-based estimation vs. linear regression model." Anesthesia and Pain Medicine 16, no. 3 (2021): 258–65. http://dx.doi.org/10.17085/apm.21021.

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Background: The optimal insertion length for right subclavian vein catheterization in infants has not been determined. This study retrospectively compared landmark-based and linear regression model-based estimation of optimal insertion length for right subclavian vein catheterization in pediatric patients of corrected age < 1 year. Methods: Fifty catheterizations of the right subclavian vein were analyzed. The landmark related distances were: from the needle insertion point (I) to the tip of the sternal head of the right clavicle (A) and from A to the midpoint (B) of the perpendicular line

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Rauniyar, Shyam, Sameer Bhalla, Daegyun Choi, and Donghoon Kim. "EKF-SLAM for Quadcopter Using Differential Flatness-Based LQR Control." Electronics 12, no. 5 (2023): 1113. http://dx.doi.org/10.3390/electronics12051113.

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SLAM (Simultaneous Localization And Mapping) in unmanned aerial vehicles can be an advantageous proposition during dangerous missions where aggressive maneuvers are paramount. This paper proposes to achieve it for a quadcopter using a differential flatness-based linear quadratic regulator while utilizing sensor measurements of an inertial measurement unit and light detection and ranging considering sensors’ constraints, such as a limited sensing range and field of view. Additionally, a strategy to reduce the computational effort of Extended Kalman Filter-based SLAM (EKF-SLAM) is proposed. To v

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Tam, Andy Yiu-Chau, Li-Wen Zha, Bryan Pak-Hei So, et al. "Depth-Camera-Based Under-Blanket Sleep Posture Classification Using Anatomical Landmark-Guided Deep Learning Model." International Journal of Environmental Research and Public Health 19, no. 20 (2022): 13491. http://dx.doi.org/10.3390/ijerph192013491.

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Emerging sleep health technologies will have an impact on monitoring patients with sleep disorders. This study proposes a new deep learning model architecture that improves the under-blanket sleep posture classification accuracy by leveraging the anatomical landmark feature through an attention strategy. The system used an integrated visible light and depth camera. Deep learning models (ResNet-34, EfficientNet B4, and ECA-Net50) were trained using depth images. We compared the models with and without an anatomical landmark coordinate input generated with an open-source pose estimation model us

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Neath, Andrew A., and Natalie Langenfeld. "A Note on the Comparison of the Bayesian and Frequentist Approaches to Estimation." Advances in Decision Sciences 2012 (October 22, 2012): 1–12. http://dx.doi.org/10.1155/2012/764254.

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Samaniego and Reneau presented a landmark study on the comparison of Bayesian and frequentist point estimators. Their findings indicate that Bayesian point estimators work well in more situations than were previously suspected. In particular, their comparison reveals how a Bayesian point estimator can improve upon a frequentist point estimator even in situations where sharp prior knowledge is not necessarily available. In the current paper, we show that similar results hold when comparing Bayesian and frequentist interval estimators. Furthermore, the development of an appropriate interval esti

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Dogancay, Kutluyil. "Self-localization from landmark bearings using pseudolinear estimation techniques." IEEE Transactions on Aerospace and Electronic Systems 50, no. 3 (2014): 2361–68. http://dx.doi.org/10.1109/taes.2014.130461.

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Cappello, Angelo, Aurelio Cappozzo, Pier Francesco La Palombara, Luigi Lucchetti, and Alberto Leardini. "Multiple anatomical landmark calibration for optimal bone pose estimation." Human Movement Science 16, no. 2-3 (1997): 259–74. http://dx.doi.org/10.1016/s0167-9457(96)00055-3.

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Stoyan, D. "Estimation of Distances and Variances in Bookstein's Landmark Model." Biometrical Journal 32, no. 7 (2007): 843–49. http://dx.doi.org/10.1002/bimj.4710320712.

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Tully, Stephen, George Kantor, and Howie Choset. "A Single-Step Maximum A Posteriori Update for Bearing-Only SLAM." Proceedings of the AAAI Conference on Artificial Intelligence 24, no. 1 (2010): 1252–57. http://dx.doi.org/10.1609/aaai.v24i1.7736.

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This paper presents a novel recursive maximum a posteriori update for the Kalman formulation of undelayed bearing-only SLAM. The estimation update step is cast as an optimization problem for which we can prove the global minimum is reachable via a bidirectional search using Gauss-Newton's method along a one-dimensional manifold. While the filter is designed for mapping just one landmark, it is easily extended to full-scale multiple-landmark SLAM. We provide this extension via a formulation of bearing-only FastSLAM. With experiments, we demonstrate accurate and convergent estimation in situatio

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Bloesch, Michael, Michael Burri, Sammy Omari, Marco Hutter, and Roland Siegwart. "Iterated extended Kalman filter based visual-inertial odometry using direct photometric feedback." International Journal of Robotics Research 36, no. 10 (2017): 1053–72. http://dx.doi.org/10.1177/0278364917728574.

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This paper presents a visual-inertial odometry framework that tightly fuses inertial measurements with visual data from one or more cameras, by means of an iterated extended Kalman filter. By employing image patches as landmark descriptors, a photometric error is derived, which is directly integrated as an innovation term in the filter update step. Consequently, the data association is an inherent part of the estimation process and no additional feature extraction or matching processes are required. Furthermore, it enables the tracking of noncorner-shaped features, such as lines, and thereby i

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Yekkehfallah, Majid, Ming Yang, Zhiao Cai, Liang Li, and Chuanxiang Wang. "Accurate 3D Localization Using RGB-TOF Camera and IMU for Industrial Mobile Robots." Robotica 39, no. 10 (2021): 1816–33. http://dx.doi.org/10.1017/s0263574720001526.

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SUMMARYLocalization based on visual natural landmarks is one of the state-of-the-art localization methods for automated vehicles that is, however, limited in fast motion and low-texture environments, which can lead to failure. This paper proposes an approach to solve these limitations with an extended Kalman filter (EKF) based on a state estimation algorithm that fuses information from a low-cost MEMS Inertial Measurement Unit and a Time-of-Flight camera. We demonstrate our results in an indoor environment. We show that the proposed approach does not require any global reflective landmark for

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Tsai, Fuan, Yih Shyh Chiou, and Huan Chang. "A Positioning Scheme Combining Kalman Filtering with Vision Assisting for Wireless Sensor Networks." Applied Mechanics and Materials 284-287 (January 2013): 2009–14. http://dx.doi.org/10.4028/www.scientific.net/amm.284-287.2009.

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This paper presents the performance of an adaptive location estimator combining Kalman filtering (KF) scheme with vision-assisted scheme for wireless sensor networks. To improve the location accuracy, a KF tracking scheme is employed at a mobile terminal to track variations of the location estimate. In addition, with a vision-assisted calibration technique based on the normalized cross-correlation scheme, the proposed approach is an accuracy enhancement procedure that effectively removes system errors causing uncertainty in measuring a dynamic environment. Therefore, using the vision-assisted

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Ajanović, Zurifa, Uzeir Ajanović, Lejla Dervišević, et al. "A Geometric Morphometrics Approach for Sex Estimation Based on the Orbital Region of Human Skulls from Bosnian Population." Scanning 2023 (April 14, 2023): 1–9. http://dx.doi.org/10.1155/2023/2223138.

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Background. Understanding the anatomy and morphological variability of the orbital region is of great importance in clinical practice, forensic medicine, and biological anthropology. Several methods are used to estimate sex based on the skeleton or parts of the skeleton: classic methods and the geometric morphometric method. The objective of this research was to analyse sex estimation of the orbital region on a sample of skulls from a Bosnian population using the geometric morphometric method. Materials and Methods. The research was conducted on three-dimensional models of 211 human adult skul

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Jiang, Suhui, Yu Kong, and Yun Fu. "Deep Geo-Constrained Auto-Encoder for Non-Landmark GPS Estimation." IEEE Transactions on Big Data 5, no. 2 (2019): 120–33. http://dx.doi.org/10.1109/tbdata.2017.2773096.

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Moeini, Amir, and Mehrzad Namvar. "Global attitude/position estimation using landmark and biased velocity measurements." IEEE Transactions on Aerospace and Electronic Systems 52, no. 2 (2016): 852–62. http://dx.doi.org/10.1109/taes.2015.140626.

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Chang, Feng-Ju, Anh Tuan Tran, Tal Hassner, Iacopo Masi, Ram Nevatia, and Gérard Medioni. "Deep, Landmark-Free FAME: Face Alignment, Modeling, and Expression Estimation." International Journal of Computer Vision 127, no. 6-7 (2019): 930–56. http://dx.doi.org/10.1007/s11263-019-01151-x.

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