This research presents an improved real-time face recognition system at a low<span><span><span style="font-family:" color:red;"=""> </span></span></span><...This research presents an improved real-time face recognition system at a low<span><span><span style="font-family:" color:red;"=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">resolution of 15 pixels with pose and emotion and resolution variations. We have designed our datasets named LRD200 and LRD100, which have been used for training and classification. The face detection part uses the Viola-Jones algorithm, and the face recognition part receives the face image from the face detection part to process it using the Local Binary Pattern Histogram (LBPH) algorithm with preprocessing using contrast limited adaptive histogram equalization (CLAHE) and face alignment. The face database in this system can be updated via our custom-built standalone android app and automatic restarting of the training and recognition process with an updated database. Using our proposed algorithm, a real-time face recognition accuracy of 78.40% at 15</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">px and 98.05% at 45</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">px have been achieved using the LRD200 database containing 200 images per person. With 100 images per person in the database (LRD100) the achieved accuracies are 60.60% at 15</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">px and 95% at 45</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">px respectively. A facial deflection of about 30</span></span></span><span><span><span><span><span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#ffffff;"="">°</span></span><span> on either side from the front face showed an average face recognition precision of 72.25%-81.85%. This face recognition system can be employed for law enforcement purposes, where the surveillance camera captures a low-resolution image because of the distance of a person from the camera. It can also be used as a surveillance system in airports, bus stations, etc., to reduce the risk of possible criminal threats.</span></span></span></span>展开更多
This article reviews the constructs of stress, appraisal, coping, according to a transactional perspective, and executive function, and presents a stress control rating scale (ECOSTRESS), which design is founded in th...This article reviews the constructs of stress, appraisal, coping, according to a transactional perspective, and executive function, and presents a stress control rating scale (ECOSTRESS), which design is founded in these constructs. This psychometric tool is useful in the assessment of cognitive control of stress, correlated with the function of dorsolateral prefrontal cortex. It has been validated for its use in the assessment of Portuguese people in situations of stress related to unemployment and economic insufficiency. Also, within the context of the cognitive control of stress, it is highlighted the usefulness of low resolution brain electromagnetic tomography (LORETA).展开更多
We present here a design of fiber fed 4000 object low resolution spectroscopy of LAMOST. And some related problems are discussed briefly. LAMOST is a 4m aperture 5° FOV telescope. 4000 object low resolution spect...We present here a design of fiber fed 4000 object low resolution spectroscopy of LAMOST. And some related problems are discussed briefly. LAMOST is a 4m aperture 5° FOV telescope. 4000 object low resolution spectroscopic observation is its main observation mode. The LAMOST instrument is mainly a multi-object spectroscopy system including 4000 independent fiber positioners, fiber optics, 14 spectrographs and 28 CCD cameras. 4000 fiber is a great challenge to present multi-fiber spectroscopy. And positioning 4000 fiber is one of the two technological difficulties for LAMOST project.展开更多
Sometimes crystals cannot diffract X-rays beyond 3.0Åresolution due to the intrinsic flexibility associated with the protein.Low resolution diffraction data not only pose a challenge to structure determination,bu...Sometimes crystals cannot diffract X-rays beyond 3.0Åresolution due to the intrinsic flexibility associated with the protein.Low resolution diffraction data not only pose a challenge to structure determination,but also hamper interpretation of mechanistic details.Crystals of a 25.6 kDa non-Pfam,hypothetical protein,PF2046,diffracted X-rays to 3.38Åresolution.A combination of SeMet derived heavy atom positions with multiple cycles of B-factor sharpening,multi-crystal averaging,restrained refinement followed by manual inspection of electron density and model building resulted in a final model with a R value of 23.5(R_(free)=24.7).The asymmetric unit was large and consisted of six molecules arranged as a homodimer of trimers.Analysis of the structure revealed the presence of a RNA binding domain suggesting a role for PF2046 in the processing of nucleic acids.展开更多
A fast version of the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG)/Institute of Atmospheric Physics (IAP) climate system model is briefly documented. Th...A fast version of the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG)/Institute of Atmospheric Physics (IAP) climate system model is briefly documented. The fast coupled model employs a low resolution version of the atmospheric component Grid Atmospheric Model of IAP/LASG (GAMIL), with the other parts of the model, namely an oceanic component LASG/IAP Climate Ocean Model (LICOM), land component Common Land Model (CLM), and sea ice component from National Center for Atmospheric Research Community Climate System Model (NCAR CCSM2), as the same as in the standard version of LASG/IAP Flexible Global Ocean Atmosphere Land System model (FGOALS_g). The parameterizations of physical and dynamical processes of the atmospheric component in the fast version are identical to the standard version, although some parameter values are different. However, by virtue of reduced horizontal resolution and increased time-step of the most time-consuming atmospheric component, it runs faster by a factor of 3 and can serve as a useful tool for longterm and large-ensemble integrations. A 1000-year control simulation of the present-day climate has been completed without flux adjustments. The final 600 years of this simulation has virtually no trends in global mean sea surface temperatures and is recommended for internal variability studies. Several aspects of the control simulation's mean climate and variability are evaluated against the observational or reanalysis data. The strengths and weaknesses of the control simulation are evaluated. The mean atmospheric circulation is well simulated, except in high latitudes. The Asian-Australian monsoonal meridional cell shows realistic features, however, an artificial rainfall center is located to the eastern periphery of the Tibetan Plateau persists throughout the year. The mean bias of SST resembles that of the standard version, appearing as a "double ITCZ" (Inter-Tropical Convergence Zone) associated with a westward extension of the equatorial eastern Pacific cold tongue. The sea ice extent is acceptable but has a higher concentration. The strength of Atlantic meridional overturning is 27.5 Sv. Evidence from the 600-year simulation suggests a modulation of internal variability on ENSO frequency, since both regular and irregular oscillations of ENSO are found during the different time periods of the long-term simulation.展开更多
Visual cortical prostheses have the potential to restore partial vision. Still limited by the low-resolution visual percepts provided by visual cortical prostheses, implant wearers can currently only "see" pixelized...Visual cortical prostheses have the potential to restore partial vision. Still limited by the low-resolution visual percepts provided by visual cortical prostheses, implant wearers can currently only "see" pixelized images, and how to obtain the specific brain responses to different pixelized images in the primary visual cortex(the implant area) is still unknown. We conducted a functional magnetic resonance imaging experiment on normal human participants to investigate the brain activation patterns in response to 18 different pixelized images. There were 100 voxels in the brain activation pattern that were selected from the primary visual cortex, and voxel size was 4 mm × 4 mm × 4 mm. Multi-voxel pattern analysis was used to test if these 18 different brain activation patterns were specific. We chose a Linear Support Vector Machine(LSVM) as the classifier in this study. The results showed that the classification accuracies of different brain activation patterns were significantly above chance level, which suggests that the classifier can successfully distinguish the brain activation patterns. Our results suggest that the specific brain activation patterns to different pixelized images can be obtained in the primary visual cortex using a 4 mm × 4 mm × 4 mm voxel size and a 100-voxel pattern.展开更多
In this paper, an efficient hybrid shock capturing scheme is proposed to obtain accurate results both in the smooth region and around discontinuities for compressible flows. The hybrid algorithm is based on a fifth-or...In this paper, an efficient hybrid shock capturing scheme is proposed to obtain accurate results both in the smooth region and around discontinuities for compressible flows. The hybrid algorithm is based on a fifth-order weighted essentially non-oscillatory (WENO) scheme in the finite volume form to solve the smooth part of the flow field, which is coupled with a characteristic-based monotone upstream-centered scheme for conservation laws (MUSCL) to capture discontinuities. The hybrid scheme is intended to combine high resolution of MUSCL scheme and low dissipation of WENO scheme. The two ingredients in this hybrid scheme are switched with an indicator. Three typical indicators are chosen and compared. MUSCL and WENO are both shock capturing schemes making the choice of the indicator parameter less crucial. Several test cases are carried out to investigate hybrid scheme with different indicators in terms of accuracy and efficiency. Numerical results demonstrate that the hybrid scheme in the present work performs well in a broad range of problems.展开更多
This paper presents a 50 Hz 15-bit analog-to-digital converter (ADC) for pixel-level implementation in CMOS image sensors. The ADC is based on charge packets counting and adopts a voltage reset technique to inject c...This paper presents a 50 Hz 15-bit analog-to-digital converter (ADC) for pixel-level implementation in CMOS image sensors. The ADC is based on charge packets counting and adopts a voltage reset technique to inject charge packets. The core circuit for charge/pulse conversion is specially optimized for low power, low noise and small area. An experimental chip with ten pixel-level ADCs has been fabricated and tested for verification. The measurement result shows a standard deviation of 1.8 LSB for full-scale output. The ADC has an area of 45 × 45μm^2 and consumes less than 2 μW in a standard 1P-6M 0.18μm CMOS process.展开更多
文摘This research presents an improved real-time face recognition system at a low<span><span><span style="font-family:" color:red;"=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">resolution of 15 pixels with pose and emotion and resolution variations. We have designed our datasets named LRD200 and LRD100, which have been used for training and classification. The face detection part uses the Viola-Jones algorithm, and the face recognition part receives the face image from the face detection part to process it using the Local Binary Pattern Histogram (LBPH) algorithm with preprocessing using contrast limited adaptive histogram equalization (CLAHE) and face alignment. The face database in this system can be updated via our custom-built standalone android app and automatic restarting of the training and recognition process with an updated database. Using our proposed algorithm, a real-time face recognition accuracy of 78.40% at 15</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">px and 98.05% at 45</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">px have been achieved using the LRD200 database containing 200 images per person. With 100 images per person in the database (LRD100) the achieved accuracies are 60.60% at 15</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">px and 95% at 45</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">px respectively. A facial deflection of about 30</span></span></span><span><span><span><span><span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#ffffff;"="">°</span></span><span> on either side from the front face showed an average face recognition precision of 72.25%-81.85%. This face recognition system can be employed for law enforcement purposes, where the surveillance camera captures a low-resolution image because of the distance of a person from the camera. It can also be used as a surveillance system in airports, bus stations, etc., to reduce the risk of possible criminal threats.</span></span></span></span>
文摘This article reviews the constructs of stress, appraisal, coping, according to a transactional perspective, and executive function, and presents a stress control rating scale (ECOSTRESS), which design is founded in these constructs. This psychometric tool is useful in the assessment of cognitive control of stress, correlated with the function of dorsolateral prefrontal cortex. It has been validated for its use in the assessment of Portuguese people in situations of stress related to unemployment and economic insufficiency. Also, within the context of the cognitive control of stress, it is highlighted the usefulness of low resolution brain electromagnetic tomography (LORETA).
文摘We present here a design of fiber fed 4000 object low resolution spectroscopy of LAMOST. And some related problems are discussed briefly. LAMOST is a 4m aperture 5° FOV telescope. 4000 object low resolution spectroscopic observation is its main observation mode. The LAMOST instrument is mainly a multi-object spectroscopy system including 4000 independent fiber positioners, fiber optics, 14 spectrographs and 28 CCD cameras. 4000 fiber is a great challenge to present multi-fiber spectroscopy. And positioning 4000 fiber is one of the two technological difficulties for LAMOST project.
基金This work was funded by the Ministry of Science and Technology of China(Grant Nos.2006AA02A316,2009DFB30310 and 2006CB910901)the National Natural Science Foundation of China(Grants Nos.30670427 and 30721003)+1 种基金the Ministry of Health of China(Grant No.2008ZX10404)CAS Research Grant(No.KSCX2-YW-R-127 and INFO-115-D01-2009).
文摘Sometimes crystals cannot diffract X-rays beyond 3.0Åresolution due to the intrinsic flexibility associated with the protein.Low resolution diffraction data not only pose a challenge to structure determination,but also hamper interpretation of mechanistic details.Crystals of a 25.6 kDa non-Pfam,hypothetical protein,PF2046,diffracted X-rays to 3.38Åresolution.A combination of SeMet derived heavy atom positions with multiple cycles of B-factor sharpening,multi-crystal averaging,restrained refinement followed by manual inspection of electron density and model building resulted in a final model with a R value of 23.5(R_(free)=24.7).The asymmetric unit was large and consisted of six molecules arranged as a homodimer of trimers.Analysis of the structure revealed the presence of a RNA binding domain suggesting a role for PF2046 in the processing of nucleic acids.
基金Acknowledgements. This work was jointly supported by the Chinese Academy of Sciences through the International Partnership Creative Group entitled "The Climate System Model Development and Application Studies", the Major State Basic Research Development Program of China (973 Program) under Grant No. 2005CB321703, and the National Natural Science Foundation of China (Grant Nos. 40675050, 40221503, 40625014). The long-term integration of the coupled model was finished on the Lenovo DeepComp 6800 supercomputer at the Supercomputing Center of the Chinese Academy of Sciences, and the IBM SP690 at the Institute of Atmospheric Physics, Chinese Academy of Sciences. The authors appreciate the contribution of Drs. R. C. Yu, Y. Q. Yu, H. L. Liu, W. P. Zheng, J. Li, X. G Xin, and Mrs. H. Wan, H. M. Li in the model development and validations.
文摘A fast version of the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG)/Institute of Atmospheric Physics (IAP) climate system model is briefly documented. The fast coupled model employs a low resolution version of the atmospheric component Grid Atmospheric Model of IAP/LASG (GAMIL), with the other parts of the model, namely an oceanic component LASG/IAP Climate Ocean Model (LICOM), land component Common Land Model (CLM), and sea ice component from National Center for Atmospheric Research Community Climate System Model (NCAR CCSM2), as the same as in the standard version of LASG/IAP Flexible Global Ocean Atmosphere Land System model (FGOALS_g). The parameterizations of physical and dynamical processes of the atmospheric component in the fast version are identical to the standard version, although some parameter values are different. However, by virtue of reduced horizontal resolution and increased time-step of the most time-consuming atmospheric component, it runs faster by a factor of 3 and can serve as a useful tool for longterm and large-ensemble integrations. A 1000-year control simulation of the present-day climate has been completed without flux adjustments. The final 600 years of this simulation has virtually no trends in global mean sea surface temperatures and is recommended for internal variability studies. Several aspects of the control simulation's mean climate and variability are evaluated against the observational or reanalysis data. The strengths and weaknesses of the control simulation are evaluated. The mean atmospheric circulation is well simulated, except in high latitudes. The Asian-Australian monsoonal meridional cell shows realistic features, however, an artificial rainfall center is located to the eastern periphery of the Tibetan Plateau persists throughout the year. The mean bias of SST resembles that of the standard version, appearing as a "double ITCZ" (Inter-Tropical Convergence Zone) associated with a westward extension of the equatorial eastern Pacific cold tongue. The sea ice extent is acceptable but has a higher concentration. The strength of Atlantic meridional overturning is 27.5 Sv. Evidence from the 600-year simulation suggests a modulation of internal variability on ENSO frequency, since both regular and irregular oscillations of ENSO are found during the different time periods of the long-term simulation.
基金supported by the National Natural Science Foundation of China,No.31070758,31271060the Natural Science Foundation of Chongqing in China,No.cstc2013jcyj A10085
文摘Visual cortical prostheses have the potential to restore partial vision. Still limited by the low-resolution visual percepts provided by visual cortical prostheses, implant wearers can currently only "see" pixelized images, and how to obtain the specific brain responses to different pixelized images in the primary visual cortex(the implant area) is still unknown. We conducted a functional magnetic resonance imaging experiment on normal human participants to investigate the brain activation patterns in response to 18 different pixelized images. There were 100 voxels in the brain activation pattern that were selected from the primary visual cortex, and voxel size was 4 mm × 4 mm × 4 mm. Multi-voxel pattern analysis was used to test if these 18 different brain activation patterns were specific. We chose a Linear Support Vector Machine(LSVM) as the classifier in this study. The results showed that the classification accuracies of different brain activation patterns were significantly above chance level, which suggests that the classifier can successfully distinguish the brain activation patterns. Our results suggest that the specific brain activation patterns to different pixelized images can be obtained in the primary visual cortex using a 4 mm × 4 mm × 4 mm voxel size and a 100-voxel pattern.
文摘In this paper, an efficient hybrid shock capturing scheme is proposed to obtain accurate results both in the smooth region and around discontinuities for compressible flows. The hybrid algorithm is based on a fifth-order weighted essentially non-oscillatory (WENO) scheme in the finite volume form to solve the smooth part of the flow field, which is coupled with a characteristic-based monotone upstream-centered scheme for conservation laws (MUSCL) to capture discontinuities. The hybrid scheme is intended to combine high resolution of MUSCL scheme and low dissipation of WENO scheme. The two ingredients in this hybrid scheme are switched with an indicator. Three typical indicators are chosen and compared. MUSCL and WENO are both shock capturing schemes making the choice of the indicator parameter less crucial. Several test cases are carried out to investigate hybrid scheme with different indicators in terms of accuracy and efficiency. Numerical results demonstrate that the hybrid scheme in the present work performs well in a broad range of problems.
基金supported by the Major National Science & Technology Program of China(No.2012ZX03004004-002)
文摘This paper presents a 50 Hz 15-bit analog-to-digital converter (ADC) for pixel-level implementation in CMOS image sensors. The ADC is based on charge packets counting and adopts a voltage reset technique to inject charge packets. The core circuit for charge/pulse conversion is specially optimized for low power, low noise and small area. An experimental chip with ten pixel-level ADCs has been fabricated and tested for verification. The measurement result shows a standard deviation of 1.8 LSB for full-scale output. The ADC has an area of 45 × 45μm^2 and consumes less than 2 μW in a standard 1P-6M 0.18μm CMOS process.