An Angle Recognition Algorithm for Tracking Moving Targets Using WiFi Signals with Adaptive Spatiotemporal Clustering

An angle estimation algorithm for tracking indoor moving targets with WiFi is proposed. First, phase calibration and static path elimination are proposed and performed on the collected channel state information signals from different antennas. Then, the angle of arrival information is obtained with the joint estimation algorithm of the angle of arrival (AOA) and time of flight (TOF). To deal with the multipath effects, we adopt the DBscan spatiotemporal clustering algorithm with adaptive parameters. In addition, the time-continuous angle of arrival information is obtained by interpolating and supplementing points to extract the dynamic signal paths better. Finally, the least-squares method is used for linear fitting to obtain the final angle information of a moving target. Experiments are conducted with the tracking data set presented with Tsinghua’s Widar 2.0. The results show that the average angle estimation error with the proposed algorithm is smaller than Widar2.0. The average angle error is about 7.18° in the classroom environment, 3.62° in the corridor environment, and 12.16° in the office environment; they are smaller than the errors of the existing system.

An Efficient Vehicle Localization Method by Using Monocular Vision

Accurate localization of surrounding vehicles helps drivers to perceive surrounding environment, which can be obtained by two parameters: depth and direction angle. This research aims to present a new efficient monocular vision based pipeline to get the vehicle’s location. We proposed a plug-and-play convolutional block combination with a basic target detection algorithm to improve the accuracy of vehicle’s bounding boxes. Then they were transformed to actual depth and angle through a conversion method which was deduced by monocular imaging geometry and camera parameters. Experimental results on KITTI dataset showed the high accuracy and efficiency of the proposed method. The mAP increased by about 2% with an additional inference time of less than 5 ms. The average depth error was about 4% for near distance objects and about 7% for far distance objects. The average angle error was about two degrees.

Topographical measurement of the attachments of the central band of the interosseous membrane on interosseous crests of the radius and ulna

Background: To suggest a reasonable isometric point based on the anatomical consistency of interosseous membrane (IOM) attachment in association with topographic characteristics of the interosseous crest, the footprints of the central band (CB) of the IOM on the radial and ulnar interosseous crests (RIC and UIC) were measured.Methods: We measured the distance from the CB footprints from each apex of both interosseous crests in 14 cadavers and the angles between the forearm axis of rotation (AOR) and the distal slopes of the RIC and UIC in 33 volunteers. Results: The CB footprints lay on the downslope of both interosseous crests with its upper margin on average 3-mm proximal from the RIC's apex consistently in the radial length, showing normality (p>0.05), and on average 16-mm distal from the UIC's apex on the ulna without satisfying normality (p<0.05). The average angle between the UIC's distal slope and the AOR was 1.3°, and the RIC's distal slope to the AOR was 14.0°, satisfying the normality tests (p>0.05), and there was no side-to-side difference in both forearms (p<0.05).Conclusions: The CB attached to the downslope just distal to the RIC's apex constrains the radius to the UIC that coincides with the AOR of the forearm circumduction, maintaining itself both isometrically and isotonically.

Calculation Method of Working Rotational Angle of Automobile Transmission System and Its Applications

The working state and operating parameters of the automobile transmission system play a key role in the vehicle noise and vibration performance. Based on the basic calculation method of relative rotational angle, this paper proposes two methods for calculating the working rotational angle and torsional stiffness of the transmission system, which can effectively obtain the key information of the transmission system under the vehicle operating state. The working rotational angle, whose initial angle should be corrected by the average angle in the neutral gear coasting condition, can reflect the actual working state of the torsional vibration damper effectively. And the accuracy of the linear torsional stiffness obtained will be above 90%. Both simulation and experimental analysis results show that these two proposed application methods have high calculation accuracies and engineering feasibility.

Rancang bangun alat monitoring fisioterapi pasien pasca stroke menggunakan sensor MPU6050 melalui media transmisi bluetooth

Stroke Transient Ischemic Attack (TIA ) adalah kondisi stroke ringan. Stroke ringan diakibatkan oleh berkurangnya suplai darah menuju otak. Kelumpuhan disebabkan oleh kurangnya aliran darah ke otak, sehingga sisi tubuh akan mengalami kelumpuhan terutama pada siku dan lutut. Fisioterapi pada pasien pasca stroke ringan dilakukan dengan metode terapi gerakan antara lain seperti penggunaan alat bantu fisioterapi pasien pasca stroke menggunakan sensor MPU6050 melalui media transmisi Bluetooth. Sistem rancangan ini membantu latihan pada pasien berbentuk sensor MPU6050 yang digunakan untuk mendeteksi sudut serta banyaknya gerakan rehabilitasi pasien pasca stroke. Sensor gyroscope menghasilkan deteksi sudut pada siku sebesar 150 dan sudut pada lutut sebesar 135 . Data yang didapatkan diproses oleh arduino nano menggunakan metode I2C. Penelitian ini bertujuan untuk merancang alat bantu fisioterapi pasien pasca stroke berbasis mikrokontroler guna memperoleh hasil yang maksimal karena bentuk alat ini yang portable. Stroke Transient Ischemic Attack (TIA) is a mild stroke condition that can be caused by reduced blood supply to the brain due to blocked blood vessels. Lack of blood flow to the brain can cause paralysis, usually only on one side of the body such as the elbows and knees. Physiotherapy in post-stroke patients is carried out using movement therapy methods, including elbow and knee flexion. Currently, patients come to the therapist or vice versa to perform therapeutic movements, so a telemonitoring system for post-stroke patient physiotherapy tools is made using the MPU6050 sensor which is connected to ESP 232 and the internet network and can be monitored by therapists and clinic admins where the therapy is done. This system helps monitor elbow and knew flexion exercises using the MPU6050 sensor which is used to detect the angle and number of rehabilitation movements of post-stroke patients. . From the results of testing the accuracy of this sensor is able to detect the angle of elbow movement from 00-1500 and knee flexion angle of 00-1350 by 99%.The telemonitoring application for physiotherapy tools for post-stroke patients based on Android is equipped with a therapist menu so that the number of movements and the average angle of movement of the knees and elbows can be monitored by the therapist, this tool can also be used anywhere and anytime due to the portable form of this tool.

Evaluation of the position and morphology of tongue and hyoid bone in skeletal Class II malocclusion based on cone beam computed tomography

Background The aim of the study was to analyze the morphology and position of the tongue and hyoid bone in skeletal Class II patients with different vertical growth patterns by cone beam computed tomography in comparison to skeletal Class I patients. Methods Ninety subjects with malocclusion were divided into skeletal Class II and Class I groups by ANB angles. Based on different vertical growth patterns, subjects in each group were divided into 3 subgroups: high-angle group (MP-FH ≥ 32.0°), average-angle group (22.0° ≤ MP-FH < 32°) and low-angle group (MP-FH < 22°). The position and morphology of the tongue and hyoid bone were evaluated in the cone beam computed tomography images. The independent Student’s t‐test was used to compare the position and morphology of the tongue and hyoid bone between skeletal Class I and Class II groups. One-way analysis of variance (ANOVA) was used to compare the measurement indexes of different vertical facial patterns in each group. Results Patients in skeletal Class II group had lower tongue posture, and the tongue body was smaller than that of those in the Class I group (P < 0.05). The position of the hyoid bone was lower in the skeletal Class II group than in Class I group (P < 0.05). The tongue length and H-Me in the skeletal Class I group with a low angle were significantly larger than those with an average angle and high angle (P < 0.05). There was no significant difference in the position or morphology of the tongue and hyoid bone in the skeletal Class II group with different vertical facial patterns (P > 0.05). Conclusion Patients with skeletal Class II malocclusion have lower tongue posture, a smaller tongue body, and greater occurrence of posterior inferior hyoid bone position than skeletal Class I patients. The length of the mandibular body in skeletal Class I patients with a horizontal growth type is longer. The position and morphology of the tongue and hyoid bone were not greatly affected by vertical facial development in skeletal Class II patients.

Anterior knee pain causes after total knee arthroplasty

The objective of the study was to determine the causes of postoperative anterior knee pain after total knee arthroplasty for preventing its occurrence and improving the surgery results.The treatment results of 77 (112 cases) patients with cruciate-retaining total knee arthroplasty without patellar replacement were analyzed. The study involved 62 (80.5 %) women and 15 (19.5 %) men. The average age (Me (25‒75 %)) of the patients was 65 (60‒70) years. There were 97 cases (87 %) with varus deformity of the knee joint, 15 cases with valgus deformity (13 %). The average angle of varus deformity was 11.22 ± 3.81°, the average angle of valgus deformity was 11 ± 4.27°. After the anterior pain appeared, patients were examined in 2‒3, 4‒5 and 6‒7 months after surgery using clinical, X-ray (anterior-posterior, lateral and axial projections, topogram of lower extremities), and EMG methods.The causes of anterior postoperative knee pain were: implant components misplacement, patellar microcirculation disorders (chondrolysis, avascular necrosis due to circular patella denervation), patellofemoral joint imbalance, and functional causes. Pain manifested itself at active leg loading and knee motion because of implant components misplacement within 2‒3 months in 34 cases (94 %), 4‒5 months ‒ in 2 cases (6 %). Patellar microcirculation disorders within 4‒5 months ‒ in 5 cases (21 %), 6‒7 months ‒ in 19 (79 %) cases. Imbalance in the patellofemoral joint within 2‒3 months ‒ in 29 cases (69 %), 4‒5 months ‒ in 13 cases (31 %). Functional causes of pain appeared within 2‒3 months ‒ in 7 cases (70 %), 4‒5 months ‒ in 3 cases (30 %).The causes of postoperative anterior pain in total knee arthroplasty can be incorrect surgical technique, changes in patellar blood supply or in the biomechanics of the patellofemoral joint due to the imbalance of the thigh muscles.

Fracture variability in basalts and its effect on river erosion: a case study in the Paraná Volcanic Province

The variation in the structural characteristics (cooling joints and tectonic fractures) of basaltic flows implies potential variability in the intensity of erosion by plucking. The erosive behavior of the rivers that sculpt these areas depends on their interaction with the diverse fracture systems. In view of this, we analyzed the effect of fracture variability in basalts on erosion in a bedrock river reach located in the Continental Volcanic Province of the Paraná Basin, southern Brazil. The 120-m-long reach is influenced somewhat by a possible fault that crosses it near one end. The fracture density and fracture direction were evaluated through field photogrammetry in seven sample areas distributed along the reach. The fracture direction and main erosion axes were also surveyed by remote piloted aircraft (RPA) aerial imaging. Tectonic fractures were identified in the field; they do not always appear in the survey of the sample areas but are evident in the RPA survey. The main erosion axes coincide with the principal fracture directions (tectonic fractures), which are disposed obliquely to the channel flow direction, making an average angle of 50°. The more abundant and multidirectional cooling joints act to control the plucking process and not to determine the erosion direction. The fracture density decreases with increasing distance from the fault crossing zone (from 9.62 to 3.73 m/m²), although the lower value is influenced by the presence of an amygdaloidal basalt zone. The higher fracture density favors more intense plucking.

SACN: A Novel Rotating Face Detector Based on Architecture Search

Rotation-Invariant Face Detection (RIPD) has been widely used in practical applications; however, the problem of the adjusting of the rotation-in-plane (RIP) angle of the human face still remains. Recently, several methods based on neural networks have been proposed to solve the RIP angle problem. However, these methods have various limitations, including low detecting speed, model size, and detecting accuracy. To solve the aforementioned problems, we propose a new network, called the Searching Architecture Calibration Network (SACN), which utilizes architecture search, fully convolutional network (FCN) and bounding box center cluster (CC). SACN was tested on the challenging Multi-Oriented Face Detection Data Set and Benchmark (MOFDDB) and achieved a higher detecting accuracy and almost the same speed as existing detectors. Moreover, the average angle error is optimized from the current 12.6° to 10.5°.

Effects of Friction Plate Hardness and Surface Orientation on the Frictional Properties of Cereal Grain

The objective of this study was to evaluate the effects of the friction plate hardness and surface orientation of a friction plate on the angle and coefficient of static friction of cereal kernels. The angle of static friction of kernels representing four major cereal species was measured on six friction plates with different hardness. The friction plates were placed in position where their surface orientation was perpendicular or parallel relative to their inclination tilt. The experimental material comprised the so-called flat seed units, where each unit consisted of three spaced kernels. The angle of static friction of every flat seed unit was measured with a dedicated device in three replications, and average values of that angle were calculated. The kernels’ angle of static friction varied considerably from 13° to 33° within the analyzed range of changes in the surface characteristics of friction plates. The average angle of static friction was influenced mainly by the surface orientation of the friction plate that came into contact with cereal kernels. The angle of static friction was 17.5% to 56.5% higher when the friction plate had perpendicular rather than parallel surface orientation. The frictional properties of kernels were less influenced by plate hardness, and clear relationships were not observed in this respect. The kernels’ coefficient of static friction remained fairly constant within the analyzed range of plate hardness values, and it was estimated at 0.4 on plates with a perpendicular surface orientation and at 0.3 on plates with a parallel surface orientation.