In this paper, we proposed a combined PCA-LPP algorithm toimprove 3D face reconstruction performance. Principal component analysis(PCA) is commonly used to compress images and extract features. Onedisadvantage of PCA ...In this paper, we proposed a combined PCA-LPP algorithm toimprove 3D face reconstruction performance. Principal component analysis(PCA) is commonly used to compress images and extract features. Onedisadvantage of PCA is local feature loss. To address this, various studies haveproposed combining a PCA-LPP-based algorithm with a locality preservingprojection (LPP). However, the existing PCA-LPP method is unsuitable for3D face reconstruction because it focuses on data classification and clustering.In the existing PCA-LPP, the adjacency graph, which primarily shows the connectionrelationships between data, is composed of the e-or k-nearest neighbortechniques. By contrast, in this study, complex and detailed parts, such aswrinkles around the eyes and mouth, can be reconstructed by composing thetopology of the 3D face model as an adjacency graph and extracting localfeatures from the connection relationship between the 3D model vertices.Experiments verified the effectiveness of the proposed method. When theproposed method was applied to the 3D face reconstruction evaluation set,a performance improvement of 10% to 20% was observed compared with theexisting PCA-based method.展开更多
COVID-19 comes from a large family of viruses identied in 1965;to date,seven groups have been recorded which have been found to affect humans.In the healthcare industry,there is much evidence that Al or machine learni...COVID-19 comes from a large family of viruses identied in 1965;to date,seven groups have been recorded which have been found to affect humans.In the healthcare industry,there is much evidence that Al or machine learning algorithms can provide effective models that solve problems in order to predict conrmed cases,recovered cases,and deaths.Many researchers and scientists in the eld of machine learning are also involved in solving this dilemma,seeking to understand the patterns and characteristics of virus attacks,so scientists may make the right decisions and take specic actions.Furthermore,many models have been considered to predict the Coronavirus outbreak,such as the retro prediction model,pandemic Kaplan’s model,and the neural forecasting model.Other research has used the time series-dependent face book prophet model for COVID-19 prediction in India’s various countries.Thus,we proposed a prediction and analysis model to predict COVID-19 in Saudi Arabia.The time series dependent face book prophet model is used to t the data and provide future predictions.This study aimed to determine the pandemic prediction of COVID-19 in Saudi Arabia,using the Time Series Analysis to observe and predict the coronavirus pandemic’s spread daily or weekly.We found that the proposed model has a low ability to forecast the recovered cases of the COVID-19 dataset.In contrast,the proposed model of death cases has a high ability to forecast the COVID-19 dataset.Finally,obtaining more data could empower the model for further validation.展开更多
This letter presents a face normalization algorithm based on 2-D face model to recognize faces with variant postures from front-view face. A 2-D face mesh model can be extracted from faces with rotation to left or rig...This letter presents a face normalization algorithm based on 2-D face model to recognize faces with variant postures from front-view face. A 2-D face mesh model can be extracted from faces with rotation to left or right and the corresponding front-view mesh model can be estimated according to the facial symmetry. Then based on the inner relationship between the two mesh models, the normalized front-view face is formed by gray level mapping. Finally, the face recognition will be finished based on Principal Component Analysis (PCA). Experiments show that better face recognition performance is achieved in this way.展开更多
Background The accurate(quantitative)analysis of 3D face deformation is a problem of increasing interest in many applications.In particular,defining a 3D model of the face deformation into a 2D target image to capture...Background The accurate(quantitative)analysis of 3D face deformation is a problem of increasing interest in many applications.In particular,defining a 3D model of the face deformation into a 2D target image to capture local and asymmetric deformations remains a challenge in existing literature.A measure of such local deformations may be a relevant index for monitoring the rehabilitation exercises of patients suffering from Par-kinson’s or Alzheimer’s disease or those recovering from a stroke.Methods In this paper,a complete framework that allows the construction of a 3D morphable shape model(3DMM)of the face is presented for fitting to a target RGB image.The model has the specific characteristic of being based on localized components of deformation.The fitting transformation is performed from 3D to 2D and guided by the correspondence between landmarks detected in the target image and those manually annotated on the average 3DMM.The fitting also has the distinction of being performed in two steps to disentangle face deformations related to the identity of the target subject from those induced by facial actions.Results The method was experimentally validated using the MICC-3D dataset,which includes 11 subjects.Each subject was imaged in one neutral pose and while performing 18 facial actions that deform the face in localized and asymmetric ways.For each acquisition,3DMM was fit to an RGB frame whereby,from the apex facial action and the neutral frame,the extent of the deformation was computed.The results indicate that the proposed approach can accurately capture face deformation,even localized and asymmetric deformations.Conclusion The proposed framework demonstrated that it is possible to measure deformations of a reconstructed 3D face model to monitor facial actions performed in response to a set of targets.Interestingly,these results were obtained using only RGB targets,without the need for 3D scans captured with costly devices.This paves the way for the use of the proposed tool in remote medical rehabilitation monitoring.展开更多
With the advancement of computer vision techniques in surveillance systems,the need for more proficient,intelligent,and sustainable facial expressions and age recognition is necessary.The main purpose of this study is...With the advancement of computer vision techniques in surveillance systems,the need for more proficient,intelligent,and sustainable facial expressions and age recognition is necessary.The main purpose of this study is to develop accurate facial expressions and an age recognition system that is capable of error-free recognition of human expression and age in both indoor and outdoor environments.The proposed system first takes an input image pre-process it and then detects faces in the entire image.After that landmarks localization helps in the formation of synthetic face mask prediction.A novel set of features are extracted and passed to a classifier for the accurate classification of expressions and age group.The proposed system is tested over two benchmark datasets,namely,the Gallagher collection person dataset and the Images of Groups dataset.The system achieved remarkable results over these benchmark datasets about recognition accuracy and computational time.The proposed system would also be applicable in different consumer application domains such as online business negotiations,consumer behavior analysis,E-learning environments,and emotion robotics.展开更多
The stability of shallow tunnels excavated in full face has been a major challenge to the scientific community for a long time. In recent years, new techniques based on the installation of a pre-reinforcement system a...The stability of shallow tunnels excavated in full face has been a major challenge to the scientific community for a long time. In recent years, new techniques based on the installation of a pre-reinforcement system ahead of the tunnel face were developed to control the deformations and surface settlements induced by the excavation and to ensure the sustainability of the tunnel in the long term. In this paper, a finite difference numerical simulation was conducted to study the behaviors and effects of two pre-reinforcement systems, i.e. the face bolting and the umbrella arch system installed in a section of southern Toulon tunnel in France. For this purpose, two approaches were taken and compared: a two-dimensional (2D) approach based on the convergence–confinement method, and a three-dimensional (3D) approach taking into account the complete modeling of the tunnel. A 2D numerical back-analysis was performed to identify the geomechanical parameters that offer satisfactory agreement with the measurement results. The limit of this method lies in the exact choice of the stress relaxation ratio λ. To overcome this uncertainty, a 3D model was developed, which permitted to study the influence of different pre-support systems on the reaction of ground mass. Both 2D and 3D numerical approaches have been fitted to measurements recorded in a section of the Toulon tunnel and the very satisfactory correspondence has allowed validating the simulations. The results show that the 3D numerical analysis with a full discretization of the inclusions seems unquestionably the most reliable approach.展开更多
To study the rock deformation with three- dimensional model under rolling forces of disc cutter, by car- rying out the circular-grooving test with disc cutter rolling around on the rock, the rock mechanical behavior u...To study the rock deformation with three- dimensional model under rolling forces of disc cutter, by car- rying out the circular-grooving test with disc cutter rolling around on the rock, the rock mechanical behavior under rolling disc cutter is studied, the mechanical model of disc cutter rolling around the groove is established, and the the- ory of single-point and double-angle variables is proposed. Based on this theory, the physics equations and geometric equations of rock mechanical behavior under disc cutters of tunnel boring machine (TBM) are studied, and then the bal- ance equations of interactive forces between disc cutter and rock are established. Accordingly, formulas about normal force, rolling force and side force of a disc cutter are de- rived, and their validity is studied by tests. Therefore, a new method and theory is proposed to study rock- breaking mech- anism of disc cutters.展开更多
Accurate and temporally consistent modeling of human bodies is essential for a wide range of applications,including character animation,understanding human social behavior,and AR/VR interfaces.Capturing human motion a...Accurate and temporally consistent modeling of human bodies is essential for a wide range of applications,including character animation,understanding human social behavior,and AR/VR interfaces.Capturing human motion accurately from a monocular image sequence remains challenging;modeling quality is strongly influenced by temporal consistency of the captured body motion.Our work presents an elegant solution to integrating temporal constraints during fitting.This increases both temporal consistency and robustness during optimization.In detail,we derive parameters of a sequence of body models,representing shape and motion of a person.We optimize these parameters over the complete image sequence,fitting a single consistent body shape while imposing temporal consistency on the body motion,assuming body joint trajectories to be linear over short time.Our approach enables the derivation of realistic 3D body models from image sequences,including jaw pose,facial expression,and articulated hands.Our experiments show that our approach accurately estimates body shape and motion,even for challenging movements and poses.Further,we apply it to the particular application of sign language analysis,where accurate and temporally consistent motion modelling is essential,and show that the approach is well-suited to this kind of application.展开更多
基金This research was supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF),funded by the Ministry of Education(2021R1I1A3058103).
文摘In this paper, we proposed a combined PCA-LPP algorithm toimprove 3D face reconstruction performance. Principal component analysis(PCA) is commonly used to compress images and extract features. Onedisadvantage of PCA is local feature loss. To address this, various studies haveproposed combining a PCA-LPP-based algorithm with a locality preservingprojection (LPP). However, the existing PCA-LPP method is unsuitable for3D face reconstruction because it focuses on data classification and clustering.In the existing PCA-LPP, the adjacency graph, which primarily shows the connectionrelationships between data, is composed of the e-or k-nearest neighbortechniques. By contrast, in this study, complex and detailed parts, such aswrinkles around the eyes and mouth, can be reconstructed by composing thetopology of the 3D face model as an adjacency graph and extracting localfeatures from the connection relationship between the 3D model vertices.Experiments verified the effectiveness of the proposed method. When theproposed method was applied to the 3D face reconstruction evaluation set,a performance improvement of 10% to 20% was observed compared with theexisting PCA-based method.
文摘COVID-19 comes from a large family of viruses identied in 1965;to date,seven groups have been recorded which have been found to affect humans.In the healthcare industry,there is much evidence that Al or machine learning algorithms can provide effective models that solve problems in order to predict conrmed cases,recovered cases,and deaths.Many researchers and scientists in the eld of machine learning are also involved in solving this dilemma,seeking to understand the patterns and characteristics of virus attacks,so scientists may make the right decisions and take specic actions.Furthermore,many models have been considered to predict the Coronavirus outbreak,such as the retro prediction model,pandemic Kaplan’s model,and the neural forecasting model.Other research has used the time series-dependent face book prophet model for COVID-19 prediction in India’s various countries.Thus,we proposed a prediction and analysis model to predict COVID-19 in Saudi Arabia.The time series dependent face book prophet model is used to t the data and provide future predictions.This study aimed to determine the pandemic prediction of COVID-19 in Saudi Arabia,using the Time Series Analysis to observe and predict the coronavirus pandemic’s spread daily or weekly.We found that the proposed model has a low ability to forecast the recovered cases of the COVID-19 dataset.In contrast,the proposed model of death cases has a high ability to forecast the COVID-19 dataset.Finally,obtaining more data could empower the model for further validation.
基金Supported by the National 863 Project(2001AA114140)and NNSF of China (90104013)
文摘This letter presents a face normalization algorithm based on 2-D face model to recognize faces with variant postures from front-view face. A 2-D face mesh model can be extracted from faces with rotation to left or right and the corresponding front-view mesh model can be estimated according to the facial symmetry. Then based on the inner relationship between the two mesh models, the normalized front-view face is formed by gray level mapping. Finally, the face recognition will be finished based on Principal Component Analysis (PCA). Experiments show that better face recognition performance is achieved in this way.
文摘Background The accurate(quantitative)analysis of 3D face deformation is a problem of increasing interest in many applications.In particular,defining a 3D model of the face deformation into a 2D target image to capture local and asymmetric deformations remains a challenge in existing literature.A measure of such local deformations may be a relevant index for monitoring the rehabilitation exercises of patients suffering from Par-kinson’s or Alzheimer’s disease or those recovering from a stroke.Methods In this paper,a complete framework that allows the construction of a 3D morphable shape model(3DMM)of the face is presented for fitting to a target RGB image.The model has the specific characteristic of being based on localized components of deformation.The fitting transformation is performed from 3D to 2D and guided by the correspondence between landmarks detected in the target image and those manually annotated on the average 3DMM.The fitting also has the distinction of being performed in two steps to disentangle face deformations related to the identity of the target subject from those induced by facial actions.Results The method was experimentally validated using the MICC-3D dataset,which includes 11 subjects.Each subject was imaged in one neutral pose and while performing 18 facial actions that deform the face in localized and asymmetric ways.For each acquisition,3DMM was fit to an RGB frame whereby,from the apex facial action and the neutral frame,the extent of the deformation was computed.The results indicate that the proposed approach can accurately capture face deformation,even localized and asymmetric deformations.Conclusion The proposed framework demonstrated that it is possible to measure deformations of a reconstructed 3D face model to monitor facial actions performed in response to a set of targets.Interestingly,these results were obtained using only RGB targets,without the need for 3D scans captured with costly devices.This paves the way for the use of the proposed tool in remote medical rehabilitation monitoring.
基金This research was supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(No.2018R1D1A1A02085645)Also,this work was supported by the KoreaMedical Device Development Fund grant funded by the Korean government(the Ministry of Science and ICT,the Ministry of Trade,Industry and Energy,the Ministry of Health&Welfare,theMinistry of Food and Drug Safety)(Project Number:202012D05-02).
文摘With the advancement of computer vision techniques in surveillance systems,the need for more proficient,intelligent,and sustainable facial expressions and age recognition is necessary.The main purpose of this study is to develop accurate facial expressions and an age recognition system that is capable of error-free recognition of human expression and age in both indoor and outdoor environments.The proposed system first takes an input image pre-process it and then detects faces in the entire image.After that landmarks localization helps in the formation of synthetic face mask prediction.A novel set of features are extracted and passed to a classifier for the accurate classification of expressions and age group.The proposed system is tested over two benchmark datasets,namely,the Gallagher collection person dataset and the Images of Groups dataset.The system achieved remarkable results over these benchmark datasets about recognition accuracy and computational time.The proposed system would also be applicable in different consumer application domains such as online business negotiations,consumer behavior analysis,E-learning environments,and emotion robotics.
文摘The stability of shallow tunnels excavated in full face has been a major challenge to the scientific community for a long time. In recent years, new techniques based on the installation of a pre-reinforcement system ahead of the tunnel face were developed to control the deformations and surface settlements induced by the excavation and to ensure the sustainability of the tunnel in the long term. In this paper, a finite difference numerical simulation was conducted to study the behaviors and effects of two pre-reinforcement systems, i.e. the face bolting and the umbrella arch system installed in a section of southern Toulon tunnel in France. For this purpose, two approaches were taken and compared: a two-dimensional (2D) approach based on the convergence–confinement method, and a three-dimensional (3D) approach taking into account the complete modeling of the tunnel. A 2D numerical back-analysis was performed to identify the geomechanical parameters that offer satisfactory agreement with the measurement results. The limit of this method lies in the exact choice of the stress relaxation ratio λ. To overcome this uncertainty, a 3D model was developed, which permitted to study the influence of different pre-support systems on the reaction of ground mass. Both 2D and 3D numerical approaches have been fitted to measurements recorded in a section of the Toulon tunnel and the very satisfactory correspondence has allowed validating the simulations. The results show that the 3D numerical analysis with a full discretization of the inclusions seems unquestionably the most reliable approach.
基金supported by the National Natural Science Foundation of China (51075147)
文摘To study the rock deformation with three- dimensional model under rolling forces of disc cutter, by car- rying out the circular-grooving test with disc cutter rolling around on the rock, the rock mechanical behavior under rolling disc cutter is studied, the mechanical model of disc cutter rolling around the groove is established, and the the- ory of single-point and double-angle variables is proposed. Based on this theory, the physics equations and geometric equations of rock mechanical behavior under disc cutters of tunnel boring machine (TBM) are studied, and then the bal- ance equations of interactive forces between disc cutter and rock are established. Accordingly, formulas about normal force, rolling force and side force of a disc cutter are de- rived, and their validity is studied by tests. Therefore, a new method and theory is proposed to study rock- breaking mech- anism of disc cutters.
基金This work was partly funded by the European Union’s Horizon 2020 Research and Innovation Programme under Agreement No.952147(Invictus)as well as the German Federal Ministry of Education and Research(BMBF)through the Research Program MoDL under Contract No.01 IS 20044.
文摘Accurate and temporally consistent modeling of human bodies is essential for a wide range of applications,including character animation,understanding human social behavior,and AR/VR interfaces.Capturing human motion accurately from a monocular image sequence remains challenging;modeling quality is strongly influenced by temporal consistency of the captured body motion.Our work presents an elegant solution to integrating temporal constraints during fitting.This increases both temporal consistency and robustness during optimization.In detail,we derive parameters of a sequence of body models,representing shape and motion of a person.We optimize these parameters over the complete image sequence,fitting a single consistent body shape while imposing temporal consistency on the body motion,assuming body joint trajectories to be linear over short time.Our approach enables the derivation of realistic 3D body models from image sequences,including jaw pose,facial expression,and articulated hands.Our experiments show that our approach accurately estimates body shape and motion,even for challenging movements and poses.Further,we apply it to the particular application of sign language analysis,where accurate and temporally consistent motion modelling is essential,and show that the approach is well-suited to this kind of application.