Journal articles: 'Wall following algorithm'

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Ando, Yoshinobu, Takashi Tsubouchi, and Shin’ichi Yuta. "A Reactive Wall Following Algorithm and Its Behavior of an Autonomous Mobile Robot with Sonar Ring." Journal of Robotics and Mechatronics 8, no. 1 (February 20, 1996): 33–39. http://dx.doi.org/10.20965/jrm.1996.p0033.

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A robust wall following algorithm for an autonomous mobile robot with a sonar ring is presented. A sonar ring consists of multiple ultrasonic range sensors which are arranged on a disc. The proposed wall-following algorithm has an ability to make a robot follow walls in various shapes. The algorithm is described as a collection of reactions based on the data from the sonar ring. The autonomous mobile robot ""Yamabico"" is used to demonstrate the experimental behaviors of the proposed algorithm. Several experimental examples of the behaviors with this autonomous mobile robot are illustrated in this paper.

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Suwoyo, Heru, Zhou Thong, Yingzhong Tian, Andi Adriansyah, and Muhammad Hafizd Ibnu Hajar. "THE ACA-BASED PID CONTROLLER FOR ENHANCING A WHEELED-MOBILE ROBOT." TEKNOKOM 5, no. 1 (April 7, 2022): 103–12. http://dx.doi.org/10.31943/teknokom.v5i1.74.

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Wall-following control of mobile robot is an important topic in the mobile robot researches. The wall-following control problem is characterized by moving the robot along the wall in a desired direction while maintaining a constants distance to the wall. The existing control algorithms become complicated in implementation and not efficient enough. Ant colony algorithm (ACA), in terms of optimizing parameters, has a faster convergence speed and features that are easy to integrate with other methods. This paper adopts ant colony algorithm to optimize PID controller, and then selects ideal control parameters. The simulation results based on MATLAB show that the control system optimized by ant colony algorithm has higher efficiency than the traditional control systems in term of RMSE.

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Suwoyo, Heru, Yingzhong Tian, Andi Adriansyah, Muhammad Hafizd Ibnu Hajar, and Tong Zhou. "The ACA-based PID Controller for Enhancing a Wheeled-Mobile Robot." Journal FORTEI-JEERI 1, no. 2 (December 28, 2020): 19–23. http://dx.doi.org/10.46962/forteijeeri.v1i2.15.

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Wall-following control of mobile robot is an important topic in the mobile robot researches. The wall-following control problem is characterized by moving the robot along the wall in a desired direction while maintaining a constants distance to the wall. The existing control algorithms become complicated in implementation and not efficient enough. Ant colony algorithm (ACA), in terms of optimizing parameters, has a faster convergence speed and features that are easy to integrate with other methods. This paper adopts ant colony algorithm to optimize PID controller, and then selects ideal control parameters. The simulation results based on MATLAB show that the control system optimized by ant colony algorithm has higher efficiency than the traditional control systems in term of RMSE.

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Wiegmann, Aaron Lee, David A. Hill, Thomas Q. Xu, Anuja K. Antony, and Keith C. Hood. "Chest wall reconstruction following iatrogenic Eloesser-type wounds: The rush algorithm." Journal of Plastic, Reconstructive & Aesthetic Surgery 72, no. 10 (October 2019): 1700–1738. http://dx.doi.org/10.1016/j.bjps.2019.06.038.

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Losken, A., V. H. Thourani, G. W. Carlson, G. E. Jones, J. H. Culbertson, J. I. Miller, and K. A. Mansour. "A reconstructive algorithm for plastic surgery following extensive chest wall resection." British Journal of Plastic Surgery 57, no. 4 (June 2004): 295–302. http://dx.doi.org/10.1016/j.bjps.2004.02.004.

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Suwoyo, Heru, Yingzhong Tian, and Muhammad Hafizd Ibnu Hajar. "ENHANCING THE PERFORMANCE OF THE WALL-FOLLOWING ROBOT BASED ON FLC-GA." SINERGI 24, no. 2 (April 17, 2020): 141. http://dx.doi.org/10.22441/sinergi.2020.2.008.

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Determination of the improper speed of the wall-following robot will produce a wavy motion. This common problem can be solved by adding a Fuzzy Logic Controller (FLC) to the system. The usage of FLC is very influential on the performance of the wall-following robot. Accuracy in the determination of speed is largely based on the setting of the membership function that becomes the value of its input. So manual setting on membership function can still be enhanced by approaching the certain optimization method. This paper describes an optimization method based on Genetic Algorithm (GA). It is used to improving the ability of FLC to control the wall-following robot controlled by FLC. To provide clarity, the wall-following robot that controlled using an FLC with manual settings will be simulated and compared with the performance of wall-following robots controlled by a fuzzy logic controller optimized by a Genetic Algorithm (FLC-GA). According to comparative results, the proposed method has been showing effectiveness in terms of stability indicated by a small error.

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Kim, Dong-Hyung, Kyoosik Shin, Chang-Soo Han, and Ji Yeong Lee. "Sensor-based navigation of a car-like robot based on Bug family algorithms." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 227, no. 6 (September 12, 2012): 1224–41. http://dx.doi.org/10.1177/0954406212458202.

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This article presents a sensor-based navigation algorithm for 3-degree-of-freedom car-like robots with a nonholonomic constraint. Similar to the classical Bug family algorithms, the proposed algorithm enables the car-like robot to navigate in a completely unknown environment by only using range sensor information. The car-like robot uses the local range sensor view to determine the local path so that it moves toward the goal. To guarantee that the car-like robot can approach the goal, the two modes of motion are repeated, termed as motion-to-goal and wall-following. The motion-to-goal behavior lets the robot directly move toward the goal and the wall-following behavior makes the car-like robot circumnavigate the obstacle boundary until it meets the leaving condition. For each behavior, the nonholonomic motion for the car-like robot is planned in terms of the turning radius at each step. The proposed algorithm is implemented with a real robot and the experimental results show the performance of the proposed algorithm.

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Chen, Cheng-Hung, Shiou-Yun Jeng, and Cheng-Jian Lin. "Mobile Robot Wall-Following Control Using Fuzzy Logic Controller with Improved Differential Search and Reinforcement Learning." Mathematics 8, no. 8 (July 31, 2020): 1254. http://dx.doi.org/10.3390/math8081254.

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In this study, a fuzzy logic controller with the reinforcement improved differential search algorithm (FLC_R-IDS) is proposed for solving a mobile robot wall-following control problem. This study uses the reward and punishment mechanisms of reinforcement learning to train the mobile robot wall-following control. The proposed improved differential search algorithm uses parameter adaptation to adjust the control parameters. To improve the exploration of the algorithm, a change in the number of superorganisms is required as it involves a stopover site. This study uses reinforcement learning to guide the behavior of the robot. When the mobile robot satisfies three reward conditions, it gets reward +1. The accumulated reward value is used to evaluate the controller and to replace the next controller training. Experimental results show that, compared with the traditional differential search algorithm and the chaos differential search algorithm, the average error value of the proposed FLC_R-IDS in the three experimental environments is reduced by 12.44%, 22.54% and 25.98%, respectively. Final, the experimental results also show that the real mobile robot using the proposed method can effectively implement the wall-following control.

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Maulidin, Indra, Muliady Muliady, and Yohana Susanthi. "Rancang Bangun Quadcopter untuk Terbang Mengikuti Dinding Menggunakan Sensor Jarak Ultrasonik HC-SR04." TELKA - Telekomunikasi Elektronika Komputasi dan Kontrol 6, no. 2 (November 24, 2020): 75–84. http://dx.doi.org/10.15575/telka.v6n2.75-84.

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Makalah ini memaparkan perancangan dan realisasi sebuah quadcopter menggunakan sensor jarak ultrasonic HC-SR04 agar dapat terbang mengikuti dinding. Algoritma yang digunakan pada realisasi quadcopter adalah algoritma Wall Follower. Fokus pembahasan sistem tersebut adalah mengimplementasikan algoritma Wall Follower pada quadcopter agar dapat terbang navigasi dalam ruang dengan cara mengikuti dinding. Kontrol pergerakan roll menggunakan mode pengontrol ON-OFF Hysteresis sedangkan pada pergerakan yaw digunakan mode pengontrol open-loop. Nilai batas bawah dan batas atas yang digunakan pada kontrol ON-OFF Hysteresis adalah 70 cm dan 100 cm. Hasil pengujian menunjukkan quadcopter berhasil terbang mengikuti dinding sejauh 10,2 m dengan ketinggian maksimum 2,14 m. This paper explained the design and realization of a quadcopter using the HC-SR04 ultrasonic distance sensor so that it can fly following the wall. The algorithm used in the quadcopter design is the Wall Follower algorithm. The focus of the discussion of the system is implementing a Wall Follower algorithm to the quadcopter so that it can navigate following the wall. The roll movement control was using Hysteresis ON-OFF control and the yaw movement control was using open-loop control. The lower and upper limit values that were used in the Hysteresis ON-OFF control are 70 cm and 100 cm. The test results show the quadcopter can fly following the wall as far as 10.2 m and reaches a maximum height of 2,14 m.

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Rehman Khan, Abdul, Ameer Tamoor Khan, Masood Salik, and Sunila Bakhsh. "An Optimally Configured HP-GRU Model Using Hyperband for the Control of Wall Following Robot." International Journal of Robotics and Control Systems 1, no. 1 (March 10, 2021): 66–74. http://dx.doi.org/10.31763/ijrcs.v1i1.281.

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In this paper, we presented an autonomous control framework for the wall following robot using an optimally configured Gated Recurrent Unit (GRU) model with the hyperband algorithm. GRU is popularly known for the time-series or sequence data, and it overcomes the vanishing gradient problem of RNN. GRU also consumes less memory and is computationally more efficient than LSTMs. The selection of hyper-parameters of the GRU model is a complex optimization problem with local minima. Usually, hyper-parameters are selected through hit and trial, which does not guarantee an optimal solution. To come around this problem, we used a hyperband algorithm for the selection of optimal parameters. It is an iterative method, which searches for the optimal configuration by discarding the least performing configurations on each iteration. The proposed HP-GRU model is used on a dataset of SCITOS G5 robots with 24 sensors mounted. The results show that HP-GRU has a mean accuracy of 0.9857 and a mean loss of 0.0810, and it is comparable with other deep learning algorithms.

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Wang, Xiangbin, Guocheng Zhang, Yushan Sun, Lei Wan, and Jian Cao. "Research on autonomous underwater vehicle wall following based on reinforcement learning and multi-sonar weighted round robin mode." International Journal of Advanced Robotic Systems 17, no. 3 (May 1, 2020): 172988142092531. http://dx.doi.org/10.1177/1729881420925311.

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When autonomous underwater vehicle following the wall, a common problem is interference between sonars equipped in the autonomous underwater vehicle. A novel work mode with weighted polling (which can be also called “weighted round robin mode”) which can independently identify the environment, dynamically establish the environmental model, and switch the operating frequency of the sonar is proposed in this article. The dynamic weighted polling mode solves the problem of sonar interference. By dynamically switching the operating frequency of the sonar, the efficiency of following the wall is improved. Through the interpolation algorithm based on velocity interpolation, the data of different frequency ranging sonar are time registered to solve the asynchronous problem of multi-sonar and the system outputs according to the frequency of high-frequency sonar. With the reinforcement learning algorithm, autonomous underwater vehicle can follow the wall at a certain distance according to the distance obtained from the polling mode. At last, the tank test verified the effectiveness of the algorithm.

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Duan, Ping, Cheng-jun Ding, Guang-ming Yuan, and Ming-lu Zhang. "Wall-Following of Mobile Robot Based on Fuzzy Genetic Algorithm to Linear Interpolating." Fuzzy Information and Engineering 2, no. 2 (June 2010): 201–11. http://dx.doi.org/10.1007/s12543-010-0045-6.

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Suwoyo, Heru, and Ferryawan Harris Kristanto. "Performance of a Wall-Following Robot Controlled by a PID-BA using Bat Algorithm Approach." International Journal of Engineering Continuity 1, no. 1 (December 10, 2022): 56–71. http://dx.doi.org/10.58291/ijec.v1i1.39.

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A wall-following robot needs a controller that applies the closed-loop concept to move actively without hindrance. Some controllers with good capabilities can act as controllers for wall follower robots, such as PID controllers. Conceptually, this controller's good performance depends on tuning the three gains before use. Instead of giving the expected and appropriate output, wrong settings will provide inaccuracies for the controller, so applying the manual method at the tuning stage is not recommended. For this reason, PID controllers are often implemented in a system supported by appropriate optimization methods, such as Genetic Algorithm or Particle Swarm Optimization. Furthermore, different from this, in this study, the Bath Algorithm is used as an alternative optimization algorithm. Its application begins with a realistic simulation of a wall-following robot. This is done to provide the possibility to implement online PID controllers and BAs. In the end, several methods are compared to find out the performance of this type of approach. Moreover, based on the observed comparative results, the proposed method gives a better value in accumulative error and convergence speed in the PID optimization process.

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Zhong, Xun Yu, Xia Fu Peng, Jie Hua Zhou, and Xiao Ci Huang. "Mobile Robot Path Planning Based on Local Environment Modeling and Adaptive Window." Applied Mechanics and Materials 48-49 (February 2011): 679–83. http://dx.doi.org/10.4028/www.scientific.net/amm.48-49.679.

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In order to solve the problem of path planning for mobile robot in unknown environment, improving overall performance of the planned path, a multi-constrained local environment modeling method is used in which the traversability, security, movement smoothness and goal-guiding are taken into consideration. On the basis of environment modeling, improved local path planning algorithms is proposed by combining Bug algorithm and rolling path planning algorithm. That improved algorithm contains Move to Goal behavior and Wall Following behavior, for overcoming local minimum, designed for robot using adaptive dynamic window. Simulation results show that the proposed methods have a good safety obstacle avoidance capabilities and environmental adaptability.

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Meng, Qing-hao, Da-wei Liu, Ming-lu Zhang, and Yi-cai Sun. "Wall-following by an Autonomously Guided Vehicle (AGV) Using a New Fuzzy-I (Integration) Controller." Robotica 17, no. 1 (January 1999): 79–86. http://dx.doi.org/10.1017/s0263574799000740.

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In this paper, the wall-following problem of an AGV is characterized by keeping a constant distance from a wall. Four Polaroid ultrasonic range sensors (sonar) are used to obtain information of the distance between the AGV and the wall. Four sonars are divided into two groups being placed at the front and back end on the right side of the AGV, respectively. A digital filter is used to get rid of disturbance and wrong readings. The former results mainly from the door and the latter from the specular reflection and accidental scattering. To obtain good dynamic and steady performances, a new compound fuzzy-I control algorithm is presented. Our methods have been verified by following a 15-meter-long wall with one door by using our TIT-1 AGV (TIT: Tianjin Institute of Technology). The results show a good performance with an error of ±2 cm from the desired distance to the wall.

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Adriansyah, Andi, and Shamsudin H. Mohd Amin. "WALL-FOLLOWING BEHAVIOR-BASED MOBILE ROBOT USING PARTICLE SWARM FUZZY CONTROLLER." Jurnal Ilmu Komputer dan Informasi 9, no. 1 (February 15, 2016): 9. http://dx.doi.org/10.21609/jiki.v9i1.367.

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Behavior-based control architecture has been broadly recognized due to their compentence in mobile robot development. Fuzzy logic system characteristics are appropriate to address the behavior design problems. Nevertheless, there are problems encountered when setting fuzzy variables manually. Consequently, most of the efforts in the field, produce certain works for the study of fuzzy systems with added learning abilities. This paper presents the improvement of fuzzy behavior-based control architecture using Particle Swarm Optimization (PSO). A wall-following behaviors used on Particle Swarm Fuzzy Controller (PSFC) are developed using the modified PSO with two stages of the PSFC process. Several simulations have been accomplished to analyze the algorithm. The promising performance have proved that the proposed control architecture for mobile robot has better capability to accomplish useful task in real office-like environment.

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Venturini, Giuseppe, Niccolò Grossi, Lorenzo Morelli, and Antonio Scippa. "A Non-Uniform Offset Algorithm for Milling Toolpath Generation Based on Boolean Operations." Applied Sciences 13, no. 1 (December 24, 2022): 208. http://dx.doi.org/10.3390/app13010208.

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In milling, the advancement of CAM strategies has increased the need for tailored algorithms for semi-finished phase computation. In some cases (e.g., thin-wall milling), variable radial engagement of the tool during the toolpath is desired, leading to the need of non-uniform machining allowance on the component that could be achieved only with a non-uniform offset algorithm, i.e., offset where the distance to the initial contour varies along that input. This work presents a general algorithm for non-uniform offset of polyline curves. The approach is based on 2D polygons and Boolean union operation, following these steps: (i) projection segments are generated, (ii) polygons (trapezoids and circular sectors) are created, (iii) Boolean union of all the polygons is performed, (iv) boundary of interest is extracted. The proposed algorithm is able to handle both internal and external offset and is robust for complexity of both the polyline and variable offset magnitude along that line, as proven by several examples and two applications to thin-wall milling provided.

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Anđelić, Nikola, Sandi Baressi Šegota, Matko Glučina, and Ivan Lorencin. "Classification of Wall Following Robot Movements Using Genetic Programming Symbolic Classifier." Machines 11, no. 1 (January 12, 2023): 105. http://dx.doi.org/10.3390/machines11010105.

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The navigation of mobile robots throughout the surrounding environment without collisions is one of the mandatory behaviors in the field of mobile robotics. The movement of the robot through its surrounding environment is achieved using sensors and a control system. The application of artificial intelligence could potentially predict the possible movement of a mobile robot if a robot encounters potential obstacles. The data used in this paper is obtained from a wall-following robot that navigates through the room following the wall in a clockwise direction with the use of 24 ultrasound sensors. The idea of this paper is to apply genetic programming symbolic classifier (GPSC) with random hyperparameter search and 5-fold cross-validation to investigate if these methods could classify the movement in the correct category (move forward, slight right turn, sharp right turn, and slight left turn) with high accuracy. Since the original dataset is imbalanced, oversampling methods (ADASYN, SMOTE, and BorderlineSMOTE) were applied to achieve the balance between class samples. These over-sampled dataset variations were used to train the GPSC algorithm with a random hyperparameter search and 5-fold cross-validation. The mean and standard deviation of accuracy (ACC), the area under the receiver operating characteristic (AUC), precision, recall, and F1−score values were used to measure the classification performance of the obtained symbolic expressions. The investigation showed that the best symbolic expressions were obtained on a dataset balanced with the BorderlineSMOTE method with ACC¯±SD(ACC), AUC¯macro±SD(AUC), Precision¯macro±SD(Precision), Recall¯macro±SD(Recall), and F1−score¯macro±SD(F1−score) equal to 0.975×1.81×10−3, 0.997±6.37×10−4, 0.975±1.82×10−3, 0.976±1.59×10−3, and 0.9785±1.74×10−3, respectively. The final test was to use the set of best symbolic expressions and apply them to the original dataset. In this case the ACC¯±SD(ACC), AUC¯±SD(AUC), Precision¯±SD(Precision), Recall¯±SD(Recall), and F1−score¯±SD(F1−Score) are equal to 0.956±0.05, 0.9536±0.057, 0.9507±0.0275, 0.9809±0.01, 0.9698±0.00725, respectively. The results of the investigation showed that this simple, non-linearly separable classification task could be solved using the GPSC algorithm with high accuracy.

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Si, Chu Dung, Pham Quoc Khanh, and Tran Van Dong. "ID: 1043 Study value of 12-lead ECG for the left free wall of accessory pathways diagnosing in patients with typical Wolff-Parkinson-White Syndrome." Biomedical Research and Therapy 4, S (September 5, 2017): 122. http://dx.doi.org/10.15419/bmrat.v4is.319.

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Objectives: This study was designed characteristics of 12-lead Electrocardiogram (ECG) for the left free wall lateral of accessory pathway (AP) localization in the typical WPW syndrome to develop a new algorithm ECG for localizing APs, and to test the accuracy of the algorithm prospectively. Methods: We studied 129 patients, in 84 patients with typical WPW syndrome have a single anterograde with the localization of APs identified by successful radiofrequency catheter ablation (RCFA) to develop a new ECG algorithm for the left free wall of localizing APs. Then this algorithm was tested prospectively in 45 patients were compared with the location of AP’s successful ablation by RCFA. Results: We found that the 12 lead ECG parameters in typical WPW syndrome such as delta wave polarity in V1, R/S ratio in V1, the transition of the QRS complex, delta wave polarity in inferior leads in diagnosis for the localization of APs by with high accuracy predicted from 74,5% to 100%, and for development of a new ECG algorithm. Then the following 45 patients were prospectively evaluated by the new derived algorithm for the left free wall pathways with high sensitivity and specificity from 75% to 100%. Conclusion: 12-lead ECG parameters in typical WPW syndrome closely related to left free wall of APs localization, in order to develop the new ECG algorithm by parameters as above; and can be used to a new ECG algorithm in predicting the location APs with high accuracy.

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Zhou, Zi Wei, Xin Yu O Yang, Wang Bao Xu, and Nai Dong Cui. "A New Algorithm of Path Planning Based on Local Data." Key Engineering Materials 531-532 (December 2012): 741–45. http://dx.doi.org/10.4028/www.scientific.net/kem.531-532.741.

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A novel new algorithm of path planning is proposed for the robot path planning based on the local data map in the robot autonomous navigation. The algorithm is used to search for the local optimal path from the current position of the robot to the target according to the known sensor data. If the robot cannot reach the target directly, the temporary target point which the robot can reach will be set up according to the optimal path. The algorithm is effective under the complicated unknown environment and moving obstacle situation which fast searching speed, it can be adapted into the practical applications and the multi-robot harmony easily. The simulation result shows that this method can provide a better planning path by comparing with the traditional planning algorithms such as artificial potential field and wall-following

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Suherman, Aan. "Fire Search and Obstcale Avoidance Robot." Telekontran : Jurnal Ilmiah Telekomunikasi, Kendali dan Elektronika Terapan 3, no. 2 (July 22, 2015): 37–46. http://dx.doi.org/10.34010/telekontran.v3i2.1881.

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Abstract - Fire search and obstacle avoidance robot are types of mobile robots that can find targets in the form of fire by tracing walls. For this robot, the navigation system uses navigation using walls. Navigation using walls is an algorithm to guide robots by navigating along walls. This system works by adjusting the distance from the wall to the robot. If a change occurs, the robot moves to adjust the distance again. This robot consists of several main components to support it when navigating through walls to reach the target. This robot consists of a flame sensor placed on the front that serves as a detector for targets in the form of fire. In addition to the flame sensor, three ultrasonic sensors are located on the left, front and right of the robot. These three ultrasonic sensors function as wall detectors. Based on the test, the percentage of success of the robot reaches the target of fire by tracing the wall of the right side is 100% in room II, in room III 70%, in room IV 70% Whereas by tracing the left wall, the percentage of success in room II is 60%, in room III 70%, in room IV 100%. The success percentage of robots reaching the target with the right search method is 80% and the left is 76.667%. Keyword : Navigation wall following, obstacle avoidance robot, mobile robot, target search robot in the form of fire

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Wang, Tian-liang, Hong-fang Song, Yu Shu, Fei Zhang, and Ya-meng He. "Temperature Field of Artificially Frozen Gravel Formation and Optimization of Freezing Pipe Layout Parameters under Seepage Flow." Geofluids 2022 (March 24, 2022): 1–11. http://dx.doi.org/10.1155/2022/1597645.

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An artificial ground freezing method is often applied to highly permeable gravel formations. Seepage flow increases energy consumption and engineering accidents under this condition. Based on the physical modeling tests, the numerical simulations were conducted. The physical modeling test examined the development of the temperature and frozen wall. Numerical modeling integrated with the ACO algorithm was established to optimize the layout parameters of the freezing pipes. The results indicate that the flowing water prolongs the closure time of the frozen wall. Meanwhile, the total thickness of the frozen wall is also reduced by the flowing water. There are significant differences in the development rates of the frozen wall in different zones. The thickness of the entire frozen wall is nonuniform owing to the seepage flow. Following optimization using the proposed algorithm, the closure time was shortened from 82.4 d to 56.9 d for the frozen wall. Moreover, the freezing efficiency increased by 30.95% after optimization, and consequently, the entire frozen wall was more uniform with a nonweak zone. A case study showed that this optimization system is an effective method for artificial ground freezing operations in geotechnical engineering.

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Ming, Li Yue, Huang Hai, Xu Yang, Zhang Guocheng, Li Jiyong, and Qin Hongde. "Cognition-based hybrid path planning for autonomous underwater vehicle target following." International Journal of Advanced Robotic Systems 16, no. 4 (July 2019): 172988141985755. http://dx.doi.org/10.1177/1729881419857554.

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Intelligent path planning is one of the key techniques for autonomous underwater vehicles for the purpose of target detection, environmental survey and so on. In order to realize automatic motion plan, an intelligent cognitive architecture for autonomous underwater vehicle motion planning has been proposed to realize complicated target detection and mobile target following in the disturbance environment. A novel adaptive ant colony optimization and particle swarm optimization fusion-based fuzzy rules optimization algorithm has been proposed to generate optimized fuzzy rules. Through this optimization algorithm, the preliminary fuzzy rules can be optimized to realize intelligent motion planning for complicated operation tasks. Experiments of channel following for wall detection and mobile target following in the oceanic environment have verified the validity of path planning method in the implementation of detection and operation tasks.

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Lin, Cheng-Jian, and Hsueh-Yi Lin. "Mobile robot wall-following control using a fuzzy cerebellar model articulation controller with group-based strategy bacterial foraging optimization." International Journal of Advanced Robotic Systems 14, no. 4 (July 1, 2017): 172988141772087. http://dx.doi.org/10.1177/1729881417720872.

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In this study, a fuzzy cerebellar model articulation controller based on group-based strategy bacterial foraging optimization is proposed for mobile robot wall-following control. In fuzzy cerebellar model articulation controller, the inputs are the distance between the sonar and the wall, and the outputs are the angular velocity of two wheels. The proposed group-based strategy bacterial foraging optimization learning algorithm is used to adjust the parameters of fuzzy cerebellar model articulation controller model. The proposed group-based strategy bacterial foraging optimization has the advantages of global search, evolutionary strategies, and group evolution to speed up the convergent rate. A new fitness function is defined to evaluate the performance of mobile robot wall-following control. The fitness function includes four assessment factors which are defined as follows: (1) maintaining safe distance between the mobile robot and the wall, (2) ensuring successfully running a cycle, (3) avoiding mobile robot collisions, and (4) mobile robot running at a maximum speed. The experimental results show that the proposed group-based strategy bacterial foraging optimization obtains a better wall-following control than other methods in unknown environments.

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Rodriguez, Eduardo D., Rachel Bluebond-Langner, Ronald P. Silverman, Grant Bochicchio, Alice Yao, Paul N. Manson, and Thomas Scalea. "Abdominal Wall Reconstruction following Severe Loss of Domain: The R Adams Cowley Shock Trauma Center Algorithm." Plastic and Reconstructive Surgery 120, no. 3 (September 2007): 669–80. http://dx.doi.org/10.1097/01.prs.0000270303.44219.76.

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Kalinović, Saša M., Dejan I. Tanikić, Jelena M. Djoković, Ružica R. Nikolić, Branislav Hadzima, and Robert Ulewicz. "Optimal Solution for an Energy Efficient Construction of a Ventilated Façade Obtained by a Genetic Algorithm." Energies 14, no. 11 (June 4, 2021): 3293. http://dx.doi.org/10.3390/en14113293.

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To design a residential or commercial building with high energy performance that would be economical at the same time, an analysis was performed that relates these two aspects of the problem. The first aspect is focused on evaluation of the thermal performance of a multi-layered wall in order to achieve the lowest energy consumption for heating and cooling. The second aspect of the analysis covered the choice of materials (type, thickness and price) so that the building has the lowest possible construction costs, but the best achieved thermal comfort. The three types of external walls with the same structure were analyzed in this paper. The lowest and highest values of the layer thickness offered by the manufacturer were chosen and their dynamic characteristics for the heat transfer were calculated. The following step was to perform optimization of the objective function, which was defined by the unit price of the material per mass of the material, that is, the economical aspect was provided. The genetic algorithm method was used to obtain the optimal thickness of the external wall layers that provided the best dynamic characteristics for the heat transfer in the defined conditions.

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Kimura, Shogo, Hisaya Tanaka, and Hideto Ide. "Automapping by Autonomous Mobile Robot using Ultrasonic Range Sensor." Journal of Robotics and Mechatronics 9, no. 4 (August 20, 1997): 310–16. http://dx.doi.org/10.20965/jrm.1997.p0310.

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For an autonomous mobile robot, how make and describe a environment map is very important problem. I made a robot that using ultrasonic range sensor and autonomous mapping by this robot at wall following algorithm. This experiment shows only using ultrasonic range sensor Mapping problem.

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Tan, Si-hao, Hui-lin Zhou, Lei Xiang, and Zhen Shu. "An Automatic Framework Using Space-Time Processing and TR-MUSIC for Subsurface and Through-Wall Multitarget Imaging." International Journal of Antennas and Propagation 2012 (2012): 1–10. http://dx.doi.org/10.1155/2012/392308.

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We present an automatic framework combined space-time signal processing with Time Reversal electromagnetic (EM) inversion for subsurface and through-wall multitarget imaging using electromagnetic waves. This framework is composed of a frequency-wavenumber (FK) filter to suppress direct wave and medium bounce, a FK migration algorithm to automatically estimate the number of targets and identify target regions, which can be used to reduce the computational complexity of the following imaging algorithm, and a EM inversion algorithm using Time Reversal Multiple Signal Classification (TR-MUSIC) to reconstruct hidden objects. The feasibility of the framework is demonstrated with simulated data generated by GPRMAX.

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Suwoyo, Heru, Yingzhong Tian, and Muhammad Hafizd Ibnu Hajar. "AN FLC-PSO ALGORITHM-CONTROLLED MOBILE ROBOT." SINERGI 24, no. 3 (July 9, 2020): 177. http://dx.doi.org/10.22441/sinergi.2020.3.002.

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The ineffectiveness of the wall-following robot (WFR) performance indicated by its surging movement has been a concerning issue. The use of a Fuzzy Logic Controller (FLC) has been considered to be an option to mitigate this problem. However, the determination of the membership function of the input value precisely adds to this problem. For this reason, a particular manner is recommended to improve the performance of FLC. This paper describes an optimization method, Particle Swarm Optimization (PSO), used to automatically determinate and arrange the FLC’s input membership function. The proposed method is simulated and validated by using MATLAB. The results are compared in terms of accumulative error. According to all the comparative results, the stability and effectiveness of the proposed method have been significantly satisfied.

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Mughal, Ubaid Ahmad, Asad Ullah Qazi, Ali Ahmed, Wasim Abbass, Safeer Abbas, Abdelatif Salmi, and Mohamed Mahmoud Sayed. "Impact of Openings on the In-Plane Strength of Confined and Unconfined Masonry Walls: A Sustainable Numerical Study." Sustainability 14, no. 12 (June 18, 2022): 7467. http://dx.doi.org/10.3390/su14127467.

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While openings are an essential requirement in buildings as a source of access, fresh air and sunlight, these openings cause a reduction in the lateral stiffness and torsional resistance of masonry wall units. A detailed numerical investigation was carried out to explore the impact of the opening percentage on the in-plane stiffness and lateral strength of unconfined and confined masonry wall panels prepared using calcium silicate bricks, for sustainable masonry structures. A commercially available FEM package (ANSYS) was used to carry out comparative analysis of ten wall panels, five of each type (confined and unconfined masonry walls) with concentrically located openings of varying sizes (0% to 16.5%). A simplified micro-modeling technique following the Newton Raphson Algorithm was adopted. Results revealed that the confined masonry approach unveiled a more reliable anti-seismic response along with improved in-plane strength in the case of confined masonry walls. The failure type shifted from pure flexural to more of a blend of shear and flexure after the opening percentage increased to 10.09% in unconfined masonry walls, which was not the case where confinement was provided. Based on the outcomes, it is strongly recommended to adopt confined masonry in highly seismic-prone areas to avoid catastrophic damage caused by earthquakes.

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Choh, Clarisa T. P., Bettina Lieske, Ridzuan Farouk, Carl Waldmann, and Rajan S. Uppal. "Algorithm for the management of large abdominal wall defects due to laparostomy wounds following intra-abdominal catastrophe." European Journal of Plastic Surgery 36, no. 9 (April 27, 2013): 553–58. http://dx.doi.org/10.1007/s00238-013-0834-3.

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Rymarczyk, Tomasz, Grzegorz Kłosowski, Anna Hoła, Jerzy Hoła, Jan Sikora, Paweł Tchórzewski, and Łukasz Skowron. "Historical Buildings Dampness Analysis Using Electrical Tomography and Machine Learning Algorithms." Energies 14, no. 5 (February 27, 2021): 1307. http://dx.doi.org/10.3390/en14051307.

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The article deals with the problem of detecting moisture in the walls of historical buildings. As part of the presented research, the following four methods based on mathematical modeling and machine learning were compared: total variation, least-angle regression, elastic net, and artificial neural networks. Based on the simulation data, the systems for the reconstruction of “pixel by pixel” tomographic images were trained. In order to test the reconstructive algorithms obtained during the research, images were generated based on real measurements and simulation cases. The method comparison was performed on the basis of three indicators: mean square error, relative image error, and image correlation coefficient. The above indicators were applied to four selected variants that corresponded to various parts of the walls. The variants differed in the dimensions of the tested wall sections, the number of electrodes used, and the resolution of the 3D image meshes. In all analyzed variants, the best results were obtained using the elastic net algorithm. In addition, all machine learning methods generated better tomographic reconstructions than the classic Total Variation method.

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Tashtoush, Yahya, Israa Haj-Mahmoud, Omar Darwish, Majdi Maabreh, Belal Alsinglawi, Mahmoud Elkhodr, and Nasser Alsaedi. "Enhancing Robots Navigation in Internet of Things Indoor Systems." Computers 10, no. 11 (November 15, 2021): 153. http://dx.doi.org/10.3390/computers10110153.

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In this study, an effective local minima detection and definition algorithm is introduced for a mobile robot navigating through unknown static environments. Furthermore, five approaches are presented and compared with the popular approach wall-following to pull the robot out of the local minima enclosure namely; Random Virtual Target, Reflected Virtual Target, Global Path Backtracking, Half Path Backtracking, and Local Path Backtracking. The proposed approaches mainly depend on changing the target location temporarily to avoid the original target’s attraction force effect on the robot. Moreover, to avoid getting trapped in the same location, a virtual obstacle is placed to cover the local minima enclosure. To include the most common shapes of deadlock situations, the proposed approaches were evaluated in four different environments; V-shaped, double U-shaped, C-shaped, and cluttered environments. The results reveal that the robot, using any of the proposed approaches, requires fewer steps to reach the destination, ranging from 59 to 73 m on average, as opposed to the wall-following strategy, which requires an average of 732 m. On average, the robot with a constant speed and reflected virtual target approach takes 103 s, whereas the identical robot with a wall-following approach takes 907 s to complete the tasks. Using a fuzzy-speed robot, the duration for the wall-following approach is greatly reduced to 507 s, while the reflected virtual target may only need up to 20% of that time. More results and detailed comparisons are embedded in the subsequent sections.

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Meel, Priyanka, Ritu Tiwari, and Anupam Shukla. "Optimization of Focused Wave Front Algorithm in Unknown Dynamic Environment for Multi-Robot Navigation." International Journal of Intelligent Mechatronics and Robotics 3, no. 4 (October 2013): 1–29. http://dx.doi.org/10.4018/ijimr.2013100101.

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Robotics is a field which includes multiple disciplines such as environment mapping, localization, path planning, path execution, area exploration etc. Path planning is the elementary requirement for all the above mentioned diversified fields. This paper presents a new method for motion planning of mobile robots which carry forward the best features of Focused Wave Front and other wave front based path planners, at the same time optimizes the algorithm in terms of path length, energy consumption and memory requirements. This research introduces a method of choosing every next step in grid based environment and also proposes a backtracking procedure to minimize turns by means of identifying landmark points in the path. Further, the authors have enhanced the functionality of Focused Wave Front algorithm by applying it in uncertain dynamic environment. The proposed method is a combination of global and local path planning as well as online and offline navigation process. A new method based on bidirectional wave propagation along the walls of obstacle and wall following behavior is being proposed for avoiding uncertain static obstacles. Considering the criticalness of moving obstacles a colored safety zone is assumed to have around them and the robot is equipped with color sensitivity. Based on the particular color (red, green, yellow) that has sensed the robot will make intelligent decisions to avoid them. The simulation result reflects how the proposed method has efficiently and safely navigates a robot towards its destination by avoiding all known and unknown obstacles. Finally the algorithms are extended for multi-robot environment.

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Belokonev, V. I., V. P. Zakharov, D. B. Grachev, S. Y. Pushkin, Z. V. Kovaleva, and D. S. Pushkina. "Optimization of surgical treatment of abdominal hernias in patients with obesity." Grekov's Bulletin of Surgery 180, no. 1 (June 2, 2021): 73–80. http://dx.doi.org/10.24884/0042-4625-2021-180-1-73-80.

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Introduction. Among patients with primary and postoperative ventral hernias, obesity of various degrees is observed in more than 50 % of patients. A severe complication of obesity is the development of panniculus – a skin-subcutaneous apron of varying severity. The hernia surgeon often performs a panniculectomy, which requires justification, taking into account both the positive and negative consequences.The objective was to improve the results of treatment of patients with hernias who are obese by developing a mathematical algorithm of indications for removing the skin-subcutaneous apron.Methods and materials. The analysis of surgical treatment of 253 obese patients with hernia aged 20 to 90 years was performed. There were 44 males (17.4 %) and 209 females (82.6 %). There are 2 groups: the first (comparison group) included 129 patients whom the hernia excision was performed without removing the skin-subcutaneous apron; the second (main group) – 124 patients who had the excision of the skin-subcutaneous apron during surgery. Indications for panniculus removal were based on the proposed mathematical algorithm, which took into account the size, clinical manifestations, associated complications, and possible consequences after surgeries while preserving it.Results. When considering the abdomen in patients with hernias and obesity from the side surface, the hanging apron in relation to the abdominal wall forms a truncated cone, or two conjugated cones that form significantly different moments of forces acting on the abdominal wall at different stages of development of the panniculus, and, therefore, can serve as the basis for the development of classification. Based on this mathematical model, the following classification of changes in the anterior abdominal wall in hernias and obesity is proposed: saggy belly; cutaneoussubcutaneous apron I, II, III degrees, which are based on calculated mathematical indicators and clinical manifestations of the disease. When treating patients with hernias and obesity during operations, the following tactical algorithms were followed: with a saggy stomach and panniculus of the 1st degree, the removal of the skin-subcutaneous apron can be refused; with the 2nd and 3rd degrees, its preservation contributes to the recurrence of the hernia due to the action of moments of forces that shift and pull the abdominal wall down.Conclusions. Clinical observations of patients with hernias and obesity have shown that the removal of the skinsubcutaneous apron did not lead to an increase in the frequency of wound and systemic complications, and therefore it should be considered a necessary stage of surgery.

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El. Hasadi, Y. M. F., A. A. Busedra, and I. M. Rustum. "Laminar Mixed Convection in the Entrance Region of Horizontal Semicircular Ducts With the Flat Wall at the Top." Journal of Heat Transfer 129, no. 9 (November 14, 2006): 1203–11. http://dx.doi.org/10.1115/1.2739612.

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Laminar mixed convection in the entrance region for horizontal semicircular ducts with the flat wall on top is investigated theoretically. The governing momentum and energy equations are solved numerically using a marching technique with the finite control volume approach following the SIMPLER algorithm. Results are obtained for the thermal boundary conditions of uniform heat input axially with uniform wall temperature circumferentially at any cross section (H1 boundary condition) with Pr=0.7 and a wide range of Grashof numbers. These results include the velocity and temperature distributions at different axial locations, axial distribution of local Nusselt number, and local average wall friction factor. It is found that Nusselt number values are close to the forced convection values near the entrance region and then decrease to a minimum as the distance from the entrance increases and then rise due to the effect of free convection before reaching constant value (fully developed). As the Grashof number increases the Nusselt number and the average wall friction factor increase in both developing and fully developed regions and the location of the onset of the secondary flow moves upstream.

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Baba Ali, Ahmed Riadh, and Sarah Madi. "A multi-stage genetic algorithm for instance selection dedicated to k nearest neighbours classification: application to robot wall following problem." International Journal of Metaheuristics 1, no. 1 (2022): 1. http://dx.doi.org/10.1504/ijmheur.2022.10051695.

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Madi, Sarah, and Ahmed Riadh Baba Ali. "A multi-stage genetic algorithm for instance selection dedicated to k nearest neighbours classification: application to robot wall following problem." International Journal of Metaheuristics 8, no. 1 (2022): 79. http://dx.doi.org/10.1504/ijmheur.2022.127832.

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Abu Bakar, Nordin, and Rosnawati Abdul Kudus. "Solving Robot Path Planning Problem Using Ant Colony Optimisation (ACO) Approach." Scientific Research Journal 6, no. 1 (June 30, 2009): 65. http://dx.doi.org/10.24191/srj.v6i1.5638.

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Learning is a complex cognitive process; thus, the algorithms that can simulate learning are also complex. The complexity is due to the fact that little is known about the learning process that can be simulated in a machine. In this study two methods have been chosen to navigate a simulated robot to a target point; namely, Ants Colony Optimisation (ACO) and the Fuzzy Approach. The focus of this paper is primarily the ACO method and the Fuzzy Approach is used as a comparative benchmark. Three scenarios were designed: the Big Hall, the Wall Following and the Volcano Challenge. These experimental scenarios represent the respective navigation frameworks found in the literature used to test learning algorithms. The results indicate that the ACO’s performance is inferior to the Fuzzy approach; justification for this has been discussed in relation to previous research in this area. Some future work to investigate this phenomenon further and improve the performance of the ACO algorithm is also presented.

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Jia, Yanfeng, Dayi Qu, Lewei Han, Lu Lin, and Jiale Hong. "Research on car-following model based on molecular dynamics." Advances in Mechanical Engineering 13, no. 2 (February 2021): 168781402199300. http://dx.doi.org/10.1177/1687814021993003.

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The car-following model has always been a research hot spot in the field of traffic flow theory. Modeling the car-following behavior can quantify the longitudinal interaction between cars, thereby understanding the characteristics of traffic flow, and revealing the inherent mechanisms of traffic congestion and other traffic phenomena. In fact, there is an asymmetry problem in the driver’s acceleration and deceleration operation. The existing car-following model ignores the difference between the acceleration and deceleration of cars. To solve this problem, the cars driving on the road are compared to molecules with interactions. Based on the molecular interaction potential function and the wall potential function, we construct a molecular car-following model. We use NGSIM data set to calibrate the parameters of the model through the genetic algorithm. Finally, we analyze the evolution rule of the disturbance in the traffic flow in different states with the help of the time-space diagram, and compare the molecular model and the classical optimal velocity model. The results show that the molecular car-following model can better describe the car-following behavior from the micro level.

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Moufida, Moussaoui, Rehab Bekkouche Souhila, Kamouche Houda, Benayoun Fadila, and Goudjil Kamel. "Identification of Soil Mechanical Parameters by Inverse Analysis Using Stochastic Methods." Selected Scientific Papers - Journal of Civil Engineering 17, no. 1 (December 1, 2022): 1–12. http://dx.doi.org/10.2478/sspjce-2022-0018.

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Abstract The mechanical parameters of the soil that must be introduced into geotechnical calculations, in particular those carried out by the Finite Element Method, are often poorly understood. The search for the numerical values of these parameters so that the models best reflect the observed reality constitutes the inverse analysis approach. In this article, we are interested in the identification of the mechanical parameters of the soil based on the principle of inverse analysis using the two methods of stochastic optimization, the genetic algorithm and the hybrid genetic algorithm with Tabu search. Soil behavior is represented by the constitutive soil Mohr-Coulomb model. The identification relates to the following two parameters: The shear modulus (G) and the friction angle (φ). The validation of these two stochastic optimization methods is done on the experimental sheet pile wall of Hochstetten in Germany. The results obtained by applying the genetic algorithm method and the hybrid genetic algorithm method for the identification of the two Mohr-Coulomb parameters (G, φ) show that the hybridization process of the genetic algorithm combined with the Tabu search method accelerated the convergence of the algorithm to the exact solution of the problem whereas the genetic algorithm alone takes a much longer computation time to reach the exact solution of the problem.

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Suwoyo, Heru, Abdurohman Abdurohman, Yifan Li, Andi Adriansyah, Yingzhong Tian, and Muhammad Hafizd Ibnu Hajar. "The Role of Block Particles Swarm Optimization to Enhance The PID-WFR Algorithm." International Journal of Engineering Continuity 1, no. 1 (December 8, 2022): 9–23. http://dx.doi.org/10.58291/ijec.v1i1.37.

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In the conventional Proportional Integral Derivation (PID) controller, the parameters are often adjusted according to the formulas and actual application. However, this empirical method will bring two disadvantages. First, testing the program takes much time and usually needs help to reach the optimal solution. Second, the PID parameters will not adapt to the new environment when the situation changes. This paper proposed a method by employing a Block Particles Swarm Optimization (BPSO) to enhance the conventional Proportional Integral Derivation (PID) algorithm to overcome the mentioned disadvantages. The genetic algorithm (GA) first optimized the PID parameters. However, its optimization time is relatively long. Then, a Block Particle Swarm Optimization (BPSO) algorithm is designed to solve the problem of long optimization time. This method was then applied to the wall-following robot problem by realistically simulating it to confirm the performance. After Compared with conventional methods, the proposed method shows a relatively stable solution.

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Çiçek, Oktay, and A. Cihat Baytaş. "Local thermal non-equilibrium conjugate forced convection and entropy generation in an aircraft cabin with air channel partially filled porous insulation." Aircraft Engineering and Aerospace Technology 94, no. 2 (November 19, 2021): 210–25. http://dx.doi.org/10.1108/aeat-02-2021-0039.

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Purpose The purpose of this study is to numerically investigate heat transfer and entropy generation between airframe and cabin-cargo departments in an aircraft. The conjugate forced convection and entropy generation in a cylindrical cavity within air channel partly filled with porous insulation material as simplified geometry for airframe and cabin-cargo departments are considered under local thermal non-equilibrium condition. Design/methodology/approach The non-dimensional governing equations for fluid and porous media discretized by finite volume method are solved using the SIMPLE algorithm with pressure and velocity correction. Findings The effects of the following parameters on the problem are investigated; Reynolds number, Darcy number, the size of inlet and exit cross-section, thermal conductivity ratio for solid and fluid phases, angle between the vertical symmetry axis and the end of channel wall exit and the gap between adiabatic channel wall and horizontal adiabatic wall separating cabin and cargo sections. Originality/value This paper can provide a basic perspective and framework for thermal design between the fuselage and cabin-cargo sections. The minimum total entropy generation number is calculated for various Reynolds numbers and thermal conductivity ratios. It is observed that the channel wall temperature increases for high Reynolds number, low Darcy number, narrower exit cross-section and wider the gap between channel wall and horizontal.

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Nguyen, L. S., B. Schaeli, D. Sage, S. Kayal, D. Jeanbourquin, D. A. Barry, and L. Rossi. "Vision-based system for the control and measurement of wastewater flow rate in sewer systems." Water Science and Technology 60, no. 9 (November 1, 2009): 2281–89. http://dx.doi.org/10.2166/wst.2009.659.

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Combined sewer overflows and stormwater discharges represent an important source of contamination to the environment. However, the harsh environment inside sewers and particular hydraulic conditions during rain events reduce the reliability of traditional flow measurement probes. In the following, we present and evaluate an in situ system for the monitoring of water flow in sewers based on video images. This paper focuses on the measurement of the water level based on image-processing techniques. The developed image-based water level algorithms identify the wall/water interface from sewer images and measure its position with respect to real world coordinates. A web-based user interface and a 3-tier system architecture enable the remote configuration of the cameras and the image-processing algorithms. Images acquired and processed by our system were found to reliably measure water levels and thereby to provide crucial information leading to better understand particular hydraulic behaviors. In terms of robustness and accuracy, the water level algorithm provided equal or better results compared to traditional water level probes in three different in situ configurations.

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Jørgensen, R. Wejnold, C. Dippmann, L. Dahl, and J. Stürup. "Treatment Algorithm for Patients with Non-arthritic Hip Pain, Suspect for an Intraarticular Pathology." Open Orthopaedics Journal 10, no. 1 (August 19, 2016): 404–11. http://dx.doi.org/10.2174/1874325001610010404.

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Background: The amount of patients referred with longstanding, non-arthritic hip pain is increasing, as are the treatment options. Left untreated hip dysplasia, acetabular retroversion and femoroacetabular impingement (FAI) may lead to osteoarthritis (OA). Finding the right treatment option for the right patient can be challenging in patients with non-arthritic hip pain. Purpose: The purpose of this study was to categorize the radiographic findings seen in patients with longstanding hip pain, suspect for an intraarticular pathology, and provide a treatment algorithm allocating a specific treatment option for each clinical condition. Material and Methods: A review of the literature was performed using Public Medline searches of MeSH terms combined with synonyms for femoroacetabular impingement, acetabular retroversion, periacetabular osteotomy and hip arthroscopy. Results: Radiographic findings associated with acetabular retroversion described in the literature were the crossover sign, the posterior wall sign and the ischial spine sign, while Wiberg’s lateral center-edge angle (CE-angle) together with Leqeusne’s acetabular index indicate hip dysplasia. A Tönnis index >2 indicates osteoarthritis, however unsatisfying results are documented following joint preserving surgery with a Tönnis index >1. Furthermore, ischial spine sign in combination with the posterior wall sign indicates total acetabular retroversion prone to periacetabular osteotomy in contrast to focal retroversion prone to hip arthroscopy. These findings were used creating a treatment algorithm for intraarticular pathologies in patients with longstanding hip pain. Conclusion: Based on the radiographic findings, the algorithm presented in this study can be a helpful tool in the decision-making for the treatment of patients with non-arthritic hip pain, suspect for intraarticular pathologies.

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Lin, Chun-Hui, Shyh-Hau Wang, and Cheng-Jian Lin. "Interval Type-2 Neural Fuzzy Controller-Based Navigation of Cooperative Load-Carrying Mobile Robots in Unknown Environments." Sensors 18, no. 12 (November 28, 2018): 4181. http://dx.doi.org/10.3390/s18124181.

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In this paper, a navigation method is proposed for cooperative load-carrying mobile robots. The behavior mode manager is used efficaciously in the navigation control method to switch between two behavior modes, wall-following mode (WFM) and goal-oriented mode (GOM), according to various environmental conditions. Additionally, an interval type-2 neural fuzzy controller based on dynamic group artificial bee colony (DGABC) is proposed in this paper. Reinforcement learning was used to develop the WFM adaptively. First, a single robot is trained to learn the WFM. Then, this control method is implemented for cooperative load-carrying mobile robots. In WFM learning, the proposed DGABC performs better than the original artificial bee colony algorithm and other improved algorithms. Furthermore, the results of cooperative load-carrying navigation control tests demonstrate that the proposed cooperative load-carrying method and the navigation method can enable the robots to carry the task item to the goal and complete the navigation mission efficiently.

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Stephens, Heidi Multhopp, and Roy Sanders. "Calcaneal Malunions: Results of a Prognostic Computed Tomography Classification System." Foot & Ankle International 17, no. 7 (July 1996): 395–401. http://dx.doi.org/10.1177/107110079601700707.

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Following nonoperative treatment of calcaneal fractures, some patients may develop a disabling malunion with associated posttraumatic arthritis of the subtalar joint, impingement of the peroneal tendons, and hindfoot malalignment. We present a computed tomography classification system for calcaneal malunions which guides treatment and is of prognostic significance. A prospective study was performed using this classification system on a series of 26 malunions treated over a 45-month period. Three distinct types of malunions were identified: type I, lateral wall exostosis without subtalar arthrosis; type II, lateral wall exostosis with subtalar arthrosis; and type III, lateral wall exostosis, subtalar arthrosis, and a varus malunion. The surgical treatment was determined by a protocol based on the specific type of malunion encountered. Results were evaluated using the Maryland Foot Score. There were 18 excellent, 5 good, and 3 fair results. Although outcomes deteriorated as malunion complexity increased, significant clinical improvement as a result of reconstructive surgery was noted in even the worst types of malunion. This algorithm is consistent, prognostic, and useful for the orthopaedic surgeon presented with a symptomatic calcaneal malunion of one of these types.

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Vasilescu, Gabriel-Dragoş, Cristian Rădeanu, Ciprian-Ilie Jitea, Bogdan Garaliu-Bușoi, and Doru Anghelache. "Technical-scientific considerations regarding the reduction of the explosion effects generated by the explosive materials on persons and industrial and civil objectives." MATEC Web of Conferences 373 (2022): 00031. http://dx.doi.org/10.1051/matecconf/202237300031.

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The attenuation is a function of a structural strength and mass of the PES structure. Relatively light or weak structures (or open PES facilities) are assumed to not attenuate any of the pressure or impulse load. These not-attenuating facilities include: Pre-engineered metal building, Hollow clay tile building, Trailer (drop or stand-alone), Tractor-trailer and Bulk/tank truck/Van truck. If there is a barricade present between the PES and the ES and this barricade meets certain criteria, the user can direct the model to reduce the pressure and impulse arriving at the ES because of the presence of the barricade. The fractional damage of the PES structure remaining intact after an explosive event is a function of the equivalent NEW (Net Explosive Weight) and the PES building type. The fractional damage (a value between 0 and 1) of each PES component (roof, front wall, side walls, and rear wall) is determined by comparing the NEW to lower-bound and upper-bound damage limits for the PES types. So, if the NEW is below the lower-bound damage limit value, then the PES structure is assumed to remain totally intact; if the NEW is greater than upper-bound damage limit value, then the PES structure is assumed to be completely destroyed; if the NEW value is between the lower-bound damage limit and upper-bound damage limit, the PES structure is partially or fractionally damaged. If the equivalent NEW is between the two values, an algorithm is used to determine how fast the PES structure transitions from zero damage to full damage as the NEW increases between the lower-bound damage limit and upper-bound damage limit values. This algorithm and all associated parameters are described in the following.

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Bendris, Bianca, and Julián Cayero Becerra. "Design and Experimental Evaluation of an Aerial Solution for Visual Inspection of Tunnel-like Infrastructures." Remote Sensing 14, no. 1 (January 2, 2022): 195. http://dx.doi.org/10.3390/rs14010195.

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Current railway tunnel inspections rely on expert operators performing a visual examination of the entire infrastructure and manually annotating encountered defects. Automatizing the inspection and maintenance task of such critical and aging infrastructures has the potential to decrease the associated costs and risks. Contributing to this aim, the present work describes an aerial robotic solution designed to perform autonomous inspections of tunnel-like infrastructures. The proposed robotic system is equipped with visual and thermal sensors and uses an inspection-driven path planning algorithm to generate a path that maximizes the quality of the gathered data in terms of photogrammetry goals while optimizing the surface coverage and the total trajectory length. The performance of the planning algorithm is demonstrated in simulation against state-of-the-art methods and a wall-following inspection trajectory. Results of a real inspection test conducted in a railway tunnel are also presented, validating the whole system operation.

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Liu, Yimin, Zhengyang Hou, Hao Zhou, Guiyun Gao, Lu Yang, Pu Wang, and Peng Wang. "Research into using a fiber Bragg grating sensor group for three-dimensional in situ stress measurement." Geoscientific Instrumentation, Methods and Data Systems 11, no. 1 (February 7, 2022): 59–73. http://dx.doi.org/10.5194/gi-11-59-2022.

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Abstract. The observation and estimation of the deep crustal stress state is a key and difficult problem for in situ stress measurement. Using a borehole wall strain gauge based on the overcoring stress-relieving method is one of the main methods of in situ stress measurement. In this paper, a strain-sensing array based on fiber Bragg grating (FBG) is designed by using the main structure of the classical hollow inclusion cell, and its layout scheme on the hollow inclusion is studied. According to the layout scheme, the in situ stress inversion algorithm of hole wall strain to stress is deduced. Following this, the triaxial loading and unloading experiment platform is built, and the calibration experiment for the FBG strain sensor is designed. Finally, Abaqus finite element software is used to simulate the in situ stress measurement process of the overcoring stress relief. The FBG strain values of each measurement direction before and after the overcoring process are extracted, and the stress inversion equation is used to carry out the stress inversion. The comparison of the inversion results proved that the FBG strain sensor group is feasible and reliable. The quasi-distributed FBG sensor module designed in this paper can invert the three-dimensional in situ stress by measuring the hole wall strain, which places a theoretical and experimental foundation for the development and application of an FBG hole wall strain gauge. It makes up for the deficiency of the existing hole wall strain gauge based on a resistance strain gauge, provides direct and accurate observations for hole wall strain measurement, and has important practical value for the development of in situ stress measurement technology.

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Journal articles on the topic 'Wall following algorithm'

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