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When mobile robot used in large-scale dynamic environments, it face more challenging problems in real-time path planning and collision-free path tracking. This paper presents a new hybrid path planning method that combines A* algorithm with adaptive window approach to conduct global path planning, real-time tracking and obstacles avoidance for mobile robot in large-scale dynamic environments. Firstly, a safe A* algorithm is designed to simplify the calculation of risk cost function and distance cost. Secondly, key path points are extracted from the planned path which generated by the safe A* to reduce the number of the grid nodes for smooth path tracking. Finally, the real-time motion planning based on adaptive window approach is adopted to achieve the simultaneous path tracking and obstacle avoidance (SPTaOA) together the switching of the key path points. The simulation and practical experiments are conducted to verify the feasibility and performance of the proposed method. The results show that the proposed hybrid path planning method, used for global path planning, tracking and obstacles avoidance, can meet the application needs of mobile robots in complex dynamic environments.

The low light conditions, abundant dust, and rocky terrain on the lunar surface pose challenges for scientific research. To effectively perceive the surrounding environment, lunar rovers are equipped with binocular cameras. In this paper, with the aim of accurately detect obstacles on the lunar surface under complex conditions, an Improved Semi-Global Matching (I-SGM) algorithm for the binocular cameras is proposed. The proposed method first carries out a cost calculation based on the improved Census transform and an adaptive window based on a connected component. Then, cost aggregation is performed using cross-based cost aggregation in the AD-Census algorithm and the initial disparity of the image is calculated via the Winner-Takes-All (WTA) strategy. Finally, disparity optimization is performed using left–right consistency detection and disparity padding. Utilizing standard test image pairs provided by the Middleburry website, the results of the test reveal that the algorithm can effectively improve the matching accuracy of the SGM algorithm, while reducing the running time of the program and enhancing noise immunity. Furthermore, when applying the I-SGM algorithm to the simulated lunar environment, the results show that the I-SGM algorithm is applicable in dim conditions on the lunar surface and can better help a lunar rover to detect obstacles during its travel.

Facial Expression Recognition (FER) is an important area in human computer interaction. FER has different applications such as analysis of student behaviour in virtual class room, driver mood detection, security systems, and medicine. The analysis of facial expressions is an interesting and exciting problem. Feature extraction plays important role in any FER system. Local Binary Pattern (LBP) and its variants are popular for feature extraction due to simplicity in computation and monotonic illumination invariant property. However, the performance of LBP is poor in the presence of noise. This work proposes a novel approach for feature extraction to improve the performance of the FER. In this approach, the LBP is calculated considering 4-neighbors and diagonal neighbours separately. Further, for affective feature description, the concept of adaptive window and averaging in radial directions is introduced. This approach reduces the length of the feature vector as well as immune to noise. Support Vector Machine (SVM) is considered for classification. Recognition rate and confusion matrix are used to assess the performance of the proposed algorithm. Extensive experimental results on JAFFE, CK, FERG and FEI face databases show significant improvement in recognition rate compared to the available techniques both in noise free and noisy conditions.

Curie depth plays an important role in the study of geological structures and resource exploration. Conventional methods usually employ a fixed window size for estimation, often resulting in significant inaccuracies. To overcome this deficiency, a new adaptive window Curie depth calculation approach is proposed, which can automatically select the optimal window size across a range of diverse geological conditions to achieve a more precise Curie depth. We validated the new approach using synthetic data, demonstrating that the average error of the bottom depth of the model was reduced compared to traditional methods. Subsequently, we applied the new method to real magnetic data from the South China Block, and a new Curie depth result was obtained and verified using measured ground heat flow data. The mean square error between the derived results and the measured ground heat flow was found to be lower than that of the Curie depth inversed by previous researchers. The adaptive window Curie depth calculation method presented herein exhibited high adaptability and accommodated various geological features. For the South China Block, the Curie depths exhibited a smooth and continuous pattern in stable regions such as cratons, while displaying a distinct uplift in the junction region between fault zones and blocks. This method can not only accurately capture the Curie depth variations across large areas, but also vividly highlight subtle changes in the Curie depth within smaller regions, demonstrating the superiority of this new approach.

Speckle noise exists inherently in the synthetic aperture radar (SAR) image. Its multiplicative property leads to lots of difficulties in SAR image processing. A novel guidance-aided triple-adaptive Frost filter is proposed in this paper, which has potential for real-time processing platforms. Firstly, a scale-adaptive sliding window sizing method is adopted to determine the neighborhood ranges for every point in the image. All the subsequent processing is based on it. Then, an adaptive calculation for the tuning factor in the Frost filter is embedded into the proposed method. Lastly, the feature information apertured from the original image is used to provide guidance for edge recovery automatically, which guarantees the satisfactory ability for feature preservation. Thus, a novel improved Frost filter is proposed with triple adaptabilities. Both the positioning accuracy and response sensitivity of the scale-adaptive sliding window sizing method are verified first. The superiority of the adaptive tuning factor combined with the scale-adaptive sliding window is confirmed by two comparison experiments. At last, the results of speckle suppression experiments on the synthetic images and two natural airborne SAR images present a better performance than other methods.

In MOOC learning, learners’ emotions have an important impact on the learning effect. In order to solve the problem that learners’ emotions are not obvious in the learning process, we propose a method to identify learner emotion by combining eye movement features and scene features. This method uses an adaptive window to partition samples and enhances sample features through fine-grained feature extraction. Using an adaptive window to partition samples can make the eye movement information in the sample more abundant, and fine-grained feature extraction from an adaptive window can increase discrimination between samples. After adopting the method proposed in this paper, the four-category emotion recognition accuracy of the single modality of eye movement reached 65.1% in MOOC learning scenarios. Both the adaptive window partition method and the fine-grained feature extraction method based on eye movement signals proposed in this paper can be applied to other modalities.

Stereo matching is still very challenging in terms of depth discontinuity, occlusions, weak texture regions, and noise resistance. To address the problems of poor noise immunity of local stereo matching and low matching accuracy in weak texture regions, a stereo matching algorithm (iFCTACP) based on improved four-moded census transform (iFCT) and a novel adaptive cross pyramid (ACP) structure were proposed. The algorithm combines the improved four-moded census transform matching cost with traditional measurement methods, which allows better anti-interference performance. The cost aggregation is performed on the adaptive cross pyramid structure, a unique structure that improves the traditional single mode of the cross. This structure not only enables regions with similar color and depth to be connected but also achieves cost smoothing across regions, significantly reducing the possibility of mismatch due to inadequate corresponding matching information and providing stronger robustness to weak texture regions. Experimental results show that the iFCTACP algorithm can effectively suppress noise interference, especially in illumination and exposure. Furthermore, it can markedly improve the error matching rate in weak texture regions with better generalization. Compared with some typical algorithms, the iFCTACP algorithm exhibits better performance whose average mismatching rate is only 3.33 $ \\% $ .

A configurable process Change Mining approach can detect changes from a collection of event logs and provide details on the unexpected behavior of all process variants of a configurable process. The strength of Change Mining lies in its ability to serve both conformance checking and enhancement purposes; users can simultaneously detect changes and ensure process conformance using a single, integrated framework. In prior research, a configurable process Change Mining algorithm has been introduced. Combined with our proposed preprocessing and change log generation methods, this algorithm forms a complete framework for detecting and recording changes in a collection of event logs. Testing the framework on synthetic data revealed limitations in detecting changes in different types of variable fragments. Consequently, it is recommended that the preprocessing approach be enhanced by applying a filtering algorithm based on sliding and adaptive windows. Our improved approach has been tested on various types of variable fragments to demonstrate its efficacy in enhancing Change Mining performance.

Stereo matching is an important method in computer vision for simulating human binocular vision to acquire spatial distance information. Implementing high-precision and real-time stereo-matching algorithms on hardware platforms with limited resources remains a significant challenge. Although the semi-global stereo-matching algorithm strikes a good balance between obtaining accuracy in the disparity map and computational complexity, it uses a fixed window for matching, resulting in lower matching accuracy in image regions with depth discontinuities and weak textures. To address the shortcomings of existing semi-global stereo-matching algorithms, an adaptive window semi-global stereo-matching algorithm is proposed, along with post-processing disparity optimization through left–right consistency check and median filtering. On test images provided by the Middlebury dataset, the average matching accuracy improved by 5.07% compared to traditional-matching algorithms. This algorithm is implemented on a Zynq UltraScale + chip, utilising 42,072 LUTs, 66,532 registers, and 101 BRAMs for the entire stereo-matching architecture. For images with a resolution of 1280 × 720 and 64 disparity levels, the final-processing speed can reach 54.24 fps.

In today's digital era, many applications generate massive data streams that must be sequenced and processed immediately. Therefore, storing large amounts of data for analysis is impractical. Now, this infinite amount of evolving data confronts concept drifts in data stream classification. Concept drift is a phenomenon in which the distribution of input data or the relationship between input data and target label changes over time. If the drifts are not addressed, the learning model's performance suffers. Non-stationary data streams must be processed as they arrive, and neural networks' built-in capabilities aid in the processing of huge non-stationary data streams. We proposed an adaptive windowing approach based on a gated recurrent unit, a variant of the recurrent neural network incrementally trained on incoming data (for the real-world airline and synthetic Streaming Ensemble Algorithm (SEA) datasets), and employed elastic weight consolidation with the Fisher information matrix to prevent forgetting. Unlike the traditional fixed window methodology, the proposed model dynamically increases the window size if the prediction is correct and reduces it if drifts occur. As a result, an adaptive recurrent neural network model can adapt to changes in the non-stationary data stream and provide consistent performance. Moreover, the findings revealed that on the airline and the SEA dataset, the proposed model outperforms state-of-the-art methods by achieving 67.74% and 91.70% accuracy, respectively. Further, the results demonstrated that the proposed model has a better accuracy of 3.6% and 1.6% for the SEA and the airline dataset, respectively.