Confusing object detection(COD),such as glass,mirrors,and camouflaged objects,represents a burgeoning visual detection task centered on pinpointing and distinguishing concealed targets within intricate backgrounds,lev...Confusing object detection(COD),such as glass,mirrors,and camouflaged objects,represents a burgeoning visual detection task centered on pinpointing and distinguishing concealed targets within intricate backgrounds,leveraging deep learning methodologies.Despite garnering increasing attention in computer vision,the focus of most existing works leans toward formulating task-specific solutions rather than delving into in-depth analyses of methodological structures.As of now,there is a notable absence of a comprehensive systematic review that focuses on recently proposed deep learning-based models for these specific tasks.To fill this gap,our study presents a pioneering review that covers both themodels and the publicly available benchmark datasets,while also identifying potential directions for future research in this field.The current dataset primarily focuses on single confusing object detection at the image level,with some studies extending to video-level data.We conduct an in-depth analysis of deep learning architectures,revealing that the current state-of-the-art(SOTA)COD methods demonstrate promising performance in single object detection.We also compile and provide detailed descriptions ofwidely used datasets relevant to these detection tasks.Our endeavor extends to discussing the limitations observed in current methodologies,alongside proposed solutions aimed at enhancing detection accuracy.Additionally,we deliberate on relevant applications and outline future research trajectories,aiming to catalyze advancements in the field of glass,mirror,and camouflaged object detection.展开更多
Gasoline compression ignition(GCI)has been considered as a promising combustion concept to yield ultralow NOX and soot emissions while maintaining high thermal efficiency.However,how to improve the low-load performanc...Gasoline compression ignition(GCI)has been considered as a promising combustion concept to yield ultralow NOX and soot emissions while maintaining high thermal efficiency.However,how to improve the low-load performance becomes an urgent issue to be solved.In this paper,a GCI engine model was built to investigate the effects of internal EGR(i-EGR)and pre-injection on in-cylinder temperature,spatial concentration of mixture and OH radical,combustion and emission characteristics,and the control strategy for improving the combustion performance was further explored.The results showed an obvious expansion of the zone with an equivalence ratio between 0.8∼1.2 is realized by higher pre-injection ratios,and the s decreases with the increase of pre-injection ratio,but increases with the increase of i-EGR ratio.The high overlap among the equivalentmixture zone,the hightemperature zone,and the OH radical-rich zone can be achieved by higher i-EGR ratio coupled with higher preinjection ratio.By increasing the pre-injection ratio,the combustion efficiency increases first and then decreases,also achieves the peak value with a pre-injection ratio of 60%and is unaffected by i-EGR.The emissions of CO,HC,NOX,and soot can also be reduced to low levels by the combination of higher i-EGR ratios and a pre-injection ratio of 60%.展开更多
A significant performance boost has been achieved in point cloud semantic segmentation by utilization of the encoder-decoder architecture and novel convolution operations for point clouds.However,co-occurrence relatio...A significant performance boost has been achieved in point cloud semantic segmentation by utilization of the encoder-decoder architecture and novel convolution operations for point clouds.However,co-occurrence relationships within a local region which can directly influence segmentation results are usually ignored by current works.In this paper,we propose a neighborhood co-occurrence matrix(NCM)to model local co-occurrence relationships in a point cloud.We generate target NCM and prediction NCM from semantic labels and a prediction map respectively.Then,Kullback-Leibler(KL)divergence is used to maximize the similarity between the target and prediction NCMs to learn the co-occurrence relationship.Moreover,for large scenes where the NCMs for a sampled point cloud and the whole scene differ greatly,we introduce a reverse form of KL divergence which can better handle the difference to supervise the prediction NCMs.We integrate our method into an existing backbone and conduct comprehensive experiments on three datasets:Semantic3D for outdoor space segmentation,and S3DIS and ScanNet v2 for indoor scene segmentation.Results indicate that our method can significantly improve upon the backbone and outperform many leading competitors.展开更多
基金supported by the NationalNatural Science Foundation of China Nos.62302167,U23A20343Shanghai Sailing Program(23YF1410500)Chenguang Program of Shanghai Education Development Foundation and Shanghai Municipal Education Commission(23CGA34).
文摘Confusing object detection(COD),such as glass,mirrors,and camouflaged objects,represents a burgeoning visual detection task centered on pinpointing and distinguishing concealed targets within intricate backgrounds,leveraging deep learning methodologies.Despite garnering increasing attention in computer vision,the focus of most existing works leans toward formulating task-specific solutions rather than delving into in-depth analyses of methodological structures.As of now,there is a notable absence of a comprehensive systematic review that focuses on recently proposed deep learning-based models for these specific tasks.To fill this gap,our study presents a pioneering review that covers both themodels and the publicly available benchmark datasets,while also identifying potential directions for future research in this field.The current dataset primarily focuses on single confusing object detection at the image level,with some studies extending to video-level data.We conduct an in-depth analysis of deep learning architectures,revealing that the current state-of-the-art(SOTA)COD methods demonstrate promising performance in single object detection.We also compile and provide detailed descriptions ofwidely used datasets relevant to these detection tasks.Our endeavor extends to discussing the limitations observed in current methodologies,alongside proposed solutions aimed at enhancing detection accuracy.Additionally,we deliberate on relevant applications and outline future research trajectories,aiming to catalyze advancements in the field of glass,mirror,and camouflaged object detection.
基金sponsored by the projects of National Natural Science Foundation of China (Grant Nos.51806127 and 52075307)Key Research and Development Program of Shandong Province (Grant No.2019GHZ016).
文摘Gasoline compression ignition(GCI)has been considered as a promising combustion concept to yield ultralow NOX and soot emissions while maintaining high thermal efficiency.However,how to improve the low-load performance becomes an urgent issue to be solved.In this paper,a GCI engine model was built to investigate the effects of internal EGR(i-EGR)and pre-injection on in-cylinder temperature,spatial concentration of mixture and OH radical,combustion and emission characteristics,and the control strategy for improving the combustion performance was further explored.The results showed an obvious expansion of the zone with an equivalence ratio between 0.8∼1.2 is realized by higher pre-injection ratios,and the s decreases with the increase of pre-injection ratio,but increases with the increase of i-EGR ratio.The high overlap among the equivalentmixture zone,the hightemperature zone,and the OH radical-rich zone can be achieved by higher i-EGR ratio coupled with higher preinjection ratio.By increasing the pre-injection ratio,the combustion efficiency increases first and then decreases,also achieves the peak value with a pre-injection ratio of 60%and is unaffected by i-EGR.The emissions of CO,HC,NOX,and soot can also be reduced to low levels by the combination of higher i-EGR ratios and a pre-injection ratio of 60%.
基金support of the National Natural Science Foundation of China(61972157)the Natural Science Foundation of Shanghai(20ZR1417700)+2 种基金the National Key R&D Program of China(2019YFC1521104,2020AAA0108301)Shanghai Municipal Commission of Economy and Information(XX-RGZN-01-19-6348)the Art Major Project of National Social Science Fund(I8ZD22).
文摘A significant performance boost has been achieved in point cloud semantic segmentation by utilization of the encoder-decoder architecture and novel convolution operations for point clouds.However,co-occurrence relationships within a local region which can directly influence segmentation results are usually ignored by current works.In this paper,we propose a neighborhood co-occurrence matrix(NCM)to model local co-occurrence relationships in a point cloud.We generate target NCM and prediction NCM from semantic labels and a prediction map respectively.Then,Kullback-Leibler(KL)divergence is used to maximize the similarity between the target and prediction NCMs to learn the co-occurrence relationship.Moreover,for large scenes where the NCMs for a sampled point cloud and the whole scene differ greatly,we introduce a reverse form of KL divergence which can better handle the difference to supervise the prediction NCMs.We integrate our method into an existing backbone and conduct comprehensive experiments on three datasets:Semantic3D for outdoor space segmentation,and S3DIS and ScanNet v2 for indoor scene segmentation.Results indicate that our method can significantly improve upon the backbone and outperform many leading competitors.