wei sun

Prof. wei sun


Research Focus & Metrics

Academic Career Length

19Years (2008-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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13 September 2018 in IEEE Transactions on Vehicular Technology
Verified
Journal Article
Closed access
WSwei sun
wei sun
MXMin Xue
Min Xue
Hongshan YuHongshan Yu
Hongshan Yu
HTHongwei TANG
Hongwei TANG
LALin Anping
Lin Anping
WiFi-Fingerprint is extensively utilized for indoor localization with the advent of the high-density wireless networks deployment and research on ubiquitous intelligence. Nevertheless, establishing an elaborate radio map for localization is a highly time-consuming task. Aiming to alleviate this problem and enhance WiFi-based indoor localization accuracy, this paper has done the following contributions. First, we present gaussian process regression (GPR) models to predict the spatial distribution of signal strength in the uncalibrated domain with limited known labeled fingerprints in reference points (RPs). As a result, deployment effort for radio mapping can be greatly reduced. Second, in order to acquire fingerprints data with higher accuracy, the compound kernels for received signal strength (RSS) prediction models are presented. Finally, the definite position is determined with the weighted Similarity K-Nearest Neighbor (Similarity-WKNN) localization algorithm when new observation RSS is collected. The experiments show that compared with the original reference fingerprints localization system, the proposed localization system explicitly reduces the localization error. The results further demonstrate that our method can augment the fingerprints and improve the accuracy of fingerprint-based indoor localization without extra manual calibration or adding dedicated infrastructure.

18 March 2020 in IEEE Transactions on Image Processing
Verified
Journal Article
Closed access
ZYZhengeng Yang
Zhengeng Yang
Hongshan YuHongshan Yu
Hongshan Yu
Mingtao FengMingtao Feng
Mingtao Feng
WSwei sun
wei sun
XLXuefei Lin
Xuefei Lin
AMAjmal Mian
Ajmal Mian
Semantic segmentation is a key step in scene understanding for autonomous driving. Although deep learning has significantly improved the segmentation accuracy, current highquality models such as PSPNet and DeepLabV3 are inefficient given their complex architectures and reliance on multi-scale inputs. Thus, it is difficult to apply them to real-time or practical applications. On the other hand, existing real-time methods cannot yet produce satisfactory results on small objects such as traffic lights, which are imperative to safe autonomous driving. In this paper, we improve the performance of real-time semantic segmentation from two perspectives, methodology and data. Specifically, we propose a real-time segmentation model coined Narrow Deep Network (NDNet) and build a synthetic dataset by inserting additional small objects into the training images. The proposed method achieves 65.7% mean intersection over union (mIoU) on the Cityscapes test set with only 8.4G floatingpoint operations (FLOPs) on 1024×2048 inputs. Furthermore, by re-training the existing PSPNet and DeepLabV3 models on our synthetic dataset, we obtained an average 2% mIoU improvement on small objects.

13 February 2023 in IEEE Transactions on Industrial Informatics
Verified
Journal Article
Closed access
JLJian Liu
Jian Liu
WSwei sun
wei sun
CLChongpei Liu
Chongpei Liu
XZXing Zhang
Xing Zhang
QFQiang Fu
Qiang Fu
Robotic grasping is one of the key functions for realizing industrial automation and human-machine interaction. However, current robotic grasping methods for unknown objects mainly focus on generating the 6D grasp poses, which cannot obtain rich object pose information and are not robust in challenging scenes. Based on this, we propose a robotic continuous grasping system that achieves end-to-end robotic grasping of intra-class unknown objects in 3D space by accurate category-level 6D object pose estimation. Specifically, to achieve object pose estimation, first, we propose a global shape extraction network (GSENet) based on ResNet1D to extract the global shape of an object category from the 3D models of intra-class known objects. Then, with the global shape as the prior feature, we propose a transformer-guided network to reconstruct the shape of intra-class unknown object. The proposed network can effectively introduce internal and mutual communication between the prior feature, current feature, and their difference feature. The internal communication is performed by self-attention. The mutual communication is performed by cross-attention to strengthen their correlation. To achieve robotic grasping for multiple objects, we propose a low-computation and effective grasping strategy based on the pre-defined vector orientation, and develop a GUI for monitoring and control. Experiments on two benchmark datasets demonstrate that our system achieves state-of-the-art (SOTA) 6D pose estimation accuracy. Moreover, the real-world experiments show that our system also achieves superior robotic grasping performance, with a grasping success rate of 81.6 $\%$ for multiple objects. Code and trained models are released at https://github.com/CNJianLiu/6D-CLGrasp

8 July 2019 in IEEE Sensors Journal
Verified
Journal Article
Closed access
QFQiang Fu
Qiang Fu
Hongshan YuHongshan Yu
Hongshan Yu
LLLihai Lai
Lihai Lai
JWJingwen Wang
Jingwen Wang
XPXia Peng
Xia Peng
MSMingui Sun
Mingui Sun
High-performance 6D pose estimation and dense 3D mapping with an RGB-D camera has recently attracted substantial research attention since this type of camera can simultaneously capture RGB and depth information. However, there is an unresolved problem in estimating pose and generating highly accurate 3D maps from challenging indoor scenes. This paper presents a real-time simultaneous localization and mapping (SLAM) system based on the RGB-D camera for indoor mobile robots. Our contributions are fourfold. First, we propose a complete high-accuracy SLAM system based on a combination of information from points and lines, which differs from most solutions that rely on only point features. Second, we propose a novel pose solver to handle point and line correspondences, in which a line-based inliers refinement (LBIR) algorithm is proposed to remove outliers. Third, we construct a unified optimization model to concurrently minimize point and line reprojection errors, and extend it to the bundle adjustment (BA) method. Fourth, extensive experiments demonstrate the robustness, accuracy, and real-time performance of the proposed system on public TUM datasets and real world scenes. The empirical results show that the proposed system achieves a comparable or better performance than state-of-the-art methods. Notably, our system can operate in nearly texture-less scenes, while other methods are prone to failure.

25 June 2018 in IEEE Journal of Biomedical and Health Informatics
Verified
Journal Article
Closed access
Qiaokang LiangQiaokang Liang
Qiaokang Liang
YNYang Nan
Yang Nan
GCGianmarc Coppola
Gianmarc Coppola
KZKunglin Zou
Kunglin Zou
WSwei sun
wei sun
GYGuan-zhen Yu
Guan-zhen Yu
Recent advances in deep learning have produced encouraging results for biomedical image segmentation; however, outcomes rely heavily on comprehensive annotation. In this paper, we propose a neural network architecture and a new algorithm, known as overlapped region forecast, for the automatic segmentation of gastric cancer images. To the best of our knowledge, this report describes the first time that deep learning has been applied to the segmentation of gastric cancer images. Moreover, a reiterative learning framework that achieves superior performance without pre-training or further manual annotation is presented to train a simple network on weakly annotated biomedical images. We customize the loss function to make the model converge faster while avoiding becoming trapped in local minima. Patch boundary errors were eliminated by our overlapped region forecast algorithm. By studying the characteristics of the model trained using two different patch extraction methods, we train iteratively and integrate predictions and weak annotations to improve the quality of the training data. Using these methods, a mean Intersection over Union coefficient (IoU) of 0.883 and a mean accuracy of 91.09% were achieved on the partially labeled dataset, thereby securing a win in the 2017 China Big Data and Artificial Intelligence Innovation and Entrepreneurship Competition.

18 June 2019 in IEEE Internet of Things Journal
Verified
Journal Article
Closed access
MXMin Xue
Min Xue
WSwei sun
wei sun
HYHongshan Yu
Hongshan Yu
HTHongwei TANG
Hongwei TANG
ALAnping Lin
Anping Lin
RZRoger Zimmermann
Roger Zimmermann
Due to the advent and pervasive deployment of wireless local area networks, WiFi-based indoor localization systems have received increasing attention in the last few years. However, their localization accuracy has always been a challenging issue. In addition, because of diverse interference such as multipath effects, the block of signals, an unstable or weak signal in itself, etc., not all the Access Points (AP) are informative for the localization. Faced with these problems, we propose a WiFi-based localization model by Modifying the large localization errors and Enhancing the Gaussian Process Regression (MEGPR). (1) To select the AP subsets that contribute more to the localization and further reduce the computational load, the Access Point Discrimination Criterion (APDC) is introduced to quantify the discernibility of the APs detected in the workspace and filter out the APs with low discrimination. (2) Second, to enhance the localization model, the localization residual is fed and learnt by the model. (3) Furthermore, the large localization errors are mitigated by the Location Modification Method (LMM). Experiments were conducted in a real environment with an area of more than 1200 m2 and the results show that compared with other existing localization models, the average localization error of the proposed MEGPR model is minimum, which further verifies the effectiveness of the proposed MEGPR localization model.