Pupil dynamics are the important characteristics of face spoofing detection.The face recognition system is one of the most used biometrics for authenticating individual identity.The main threats to the facial recognit...Pupil dynamics are the important characteristics of face spoofing detection.The face recognition system is one of the most used biometrics for authenticating individual identity.The main threats to the facial recognition system are different types of presentation attacks like print attacks,3D mask attacks,replay attacks,etc.The proposed model uses pupil characteristics for liveness detection during the authentication process.The pupillary light reflex is an involuntary reaction controlling the pupil’s diameter at different light intensities.The proposed framework consists of two-phase methodologies.In the first phase,the pupil’s diameter is calculated by applying stimulus(light)in one eye of the subject and calculating the constriction of the pupil size on both eyes in different video frames.The above measurement is converted into feature space using Kohn and Clynes model-defined parameters.The Support Vector Machine is used to classify legitimate subjects when the diameter change is normal(or when the eye is alive)or illegitimate subjects when there is no change or abnormal oscillations of pupil behavior due to the presence of printed photograph,video,or 3D mask of the subject in front of the camera.In the second phase,we perform the facial recognition process.Scale-invariant feature transform(SIFT)is used to find the features from the facial images,with each feature having a size of a 128-dimensional vector.These features are scale,rotation,and orientation invariant and are used for recognizing facial images.The brute force matching algorithm is used for matching features of two different images.The threshold value we considered is 0.08 for good matches.To analyze the performance of the framework,we tested our model in two Face antispoofing datasets named Replay attack datasets and CASIA-SURF datasets,which were used because they contain the videos of the subjects in each sample having three modalities(RGB,IR,Depth).The CASIA-SURF datasets showed an 89.9%Equal Error Rate,while the Replay Attack datasets showed a 92.1%Equal Error Rate.展开更多
AIM:To establish pupil diameter measurement algorithms based on infrared images that can be used in real-world clinical settings.METHODS:A total of 188 patients from outpatient clinic at He Eye Specialist Shenyang Hos...AIM:To establish pupil diameter measurement algorithms based on infrared images that can be used in real-world clinical settings.METHODS:A total of 188 patients from outpatient clinic at He Eye Specialist Shenyang Hospital from Spetember to December 2022 were included,and 13470 infrared pupil images were collected for the study.All infrared images for pupil segmentation were labeled using the Labelme software.The computation of pupil diameter is divided into four steps:image pre-processing,pupil identification and localization,pupil segmentation,and diameter calculation.Two major models are used in the computation process:the modified YoloV3 and Deeplabv 3+models,which must be trained beforehand.RESULTS:The test dataset included 1348 infrared pupil images.On the test dataset,the modified YoloV3 model had a detection rate of 99.98% and an average precision(AP)of 0.80 for pupils.The DeeplabV3+model achieved a background intersection over union(IOU)of 99.23%,a pupil IOU of 93.81%,and a mean IOU of 96.52%.The pupil diameters in the test dataset ranged from 20 to 56 pixels,with a mean of 36.06±6.85 pixels.The absolute error in pupil diameters between predicted and actual values ranged from 0 to 7 pixels,with a mean absolute error(MAE)of 1.06±0.96 pixels.CONCLUSION:This study successfully demonstrates a robust infrared image-based pupil diameter measurement algorithm,proven to be highly accurate and reliable for clinical application.展开更多
The pupil recognition method is helpful in many real-time systems,including ophthalmology testing devices,wheelchair assistance,and so on.The pupil detection system is a very difficult process in a wide range of datas...The pupil recognition method is helpful in many real-time systems,including ophthalmology testing devices,wheelchair assistance,and so on.The pupil detection system is a very difficult process in a wide range of datasets due to problems caused by varying pupil size,occlusion of eyelids,and eyelashes.Deep Convolutional Neural Networks(DCNN)are being used in pupil recognition systems and have shown promising results in terms of accuracy.To improve accuracy and cope with larger datasets,this research work proposes BOC(BAT Optimized CNN)-IrisNet,which consists of optimizing input weights and hidden layers of DCNN using the evolutionary BAT algorithm to efficiently find the human eye pupil region.The proposed method is based on very deep architecture and many tricks from recently developed popular CNNs.Experiment results show that the BOC-IrisNet proposal can efficiently model iris microstructures and provides a stable discriminating iris representation that is lightweight,easy to implement,and of cutting-edge accuracy.Finally,the region-based black box method for determining pupil center coordinates was introduced.The proposed architecture was tested using various IRIS databases,including the CASIA(Chinese academy of the scientific research institute of automation)Iris V4 dataset,which has 99.5%sensitivity and 99.75%accuracy,and the IIT(Indian Institute of Technology)Delhi dataset,which has 99.35%specificity and MMU(Multimedia University)99.45%accuracy,which is higher than the existing architectures.展开更多
The objective of this study was to experimentally evaluate children’s daily food memory and eating habits.The study found that the gender and school location had an impact on the nutritional condition of primary scho...The objective of this study was to experimentally evaluate children’s daily food memory and eating habits.The study found that the gender and school location had an impact on the nutritional condition of primary school students as well as the school food scheme.The investigations were based on three hypotheses and three research questions.In this study,the Eating Habits and Daily Dietary Recall Scale was the tool utilized to gather data(EPDDRS).Four experts—three from the department of vocational education and one lecturer in test and measurement evaluation—validated the instrument’s face.The dependability indices of EPDDRS were calculated using Cronbach’s Alpha.While delivering the instruments,the researcher used the direct administration and retrieval approach.58 instructors and a sample size of 1240 students were selected using a systematic random selection approach.The obtained data was examined using mean and standard deviation to address the research objectives,and the null hypotheses were tested using t-test statistics and Analysis of variance(ANOVA)at the 0.05 level of significance.The main conclusions of this study were that the school meal program had a favorable impact on the students’nutritional status.Also,a balanced ration of nutrient-dense meals that were suitably varied was supplied for the students via the school food program.Also,the findings revealed a substantial difference in the mean assessments of male and female students about their eating patterns.On the school meal program’s dietary recall list,students from high,middle,and low socioeconomic status differ significantly.Recommendations were given to the government,schools,and parents based on the study’s findings.The study’s shortcomings were discussed,and recommendations for more research were made.展开更多
Recently,many researchers have tried to develop a robust,fast,and accurate algorithm.This algorithm is for eye-tracking and detecting pupil position in many applications such as head-mounted eye tracking,gaze-based hu...Recently,many researchers have tried to develop a robust,fast,and accurate algorithm.This algorithm is for eye-tracking and detecting pupil position in many applications such as head-mounted eye tracking,gaze-based human-computer interaction,medical applications(such as deaf and diabetes patients),and attention analysis.Many real-world conditions challenge the eye appearance,such as illumination,reflections,and occasions.On the other hand,individual differences in eye physiology and other sources of noise,such as contact lenses or make-up.The present work introduces a robust pupil detection algorithm with and higher accuracy than the previous attempts for real-time analytics applications.The proposed circular hough transform with morphing canny edge detection for Pupillometery(CHMCEP)algorithm can detect even the blurred or noisy images by using different filtering methods in the pre-processing or start phase to remove the blur and noise and finally the second filtering process before the circular Hough transform for the center fitting to make sure better accuracy.The performance of the proposed CHMCEP algorithm was tested against recent pupil detection methods.Simulations and results show that the proposed CHMCEP algorithm achieved detection rates of 87.11,78.54,58,and 78 according to´Swirski,ExCuSe,Else,and labeled pupils in the wild(LPW)data sets,respectively.These results show that the proposed approach performs better than the other pupil detection methods by a large margin by providing exact and robust pupil positions on challenging ordinary eye pictures.展开更多
Human eye detection has become an area of interest in the field of computer vision with an extensive range of applications in human-computer interaction,disease diagnosis,and psychological and physiological studies.Ga...Human eye detection has become an area of interest in the field of computer vision with an extensive range of applications in human-computer interaction,disease diagnosis,and psychological and physiological studies.Gaze-tracking systems are an important research topic in the human-computer interaction field.As one of the core modules of the head-mounted gaze-tracking system,pupil positioning affects the accuracy and stability of the system.By tracking eye movements to better locate the center of the pupil,this paper proposes a method for pupil positioning based on the starburst model.The method uses vertical and horizontal coordinate integral projections in the rectangular region of the human eye for accurate positioning and applies a linear interpolation method that is based on a circular model to the reflections in the human eye.In this paper,we propose a method for detecting the feature points of the pupil edge based on the starburst model,which clusters feature points and uses the RANdom SAmple Consensus(RANSAC)algorithm to perform ellipse fitting of the pupil edge to accurately locate the pupil center.Our experimental results show that the algorithm has higher precision,higher efficiency and more robustness than other algorithms and excellent accuracy even when the image of the pupil is incomplete.展开更多
for the past few decades,the way to achieve good teacher-pupil rapport in the classroom has been at the center of heated debate all over the world.All teachers should provide a good studying environment for pupils.Thi...for the past few decades,the way to achieve good teacher-pupil rapport in the classroom has been at the center of heated debate all over the world.All teachers should provide a good studying environment for pupils.This paper will focus on four parts to discuss this issue.展开更多
A great earthquake broke out in WenChuan. A lot of people were killed, but somany people were rescused by soldiers.Here are stories about three recused pupils.Langzhen, aged three, was rescusedby the soldiers after be...A great earthquake broke out in WenChuan. A lot of people were killed, but somany people were rescused by soldiers.Here are stories about three recused pupils.Langzhen, aged three, was rescusedby the soldiers after being buried in ruinsfor 10 hours.展开更多
AIM: To study the distribution of ocular higher-order aberrations(HOAs) and mesopic pupil size in individuals screened for refractive surgery. · METHODS: Ocular HOAs and mesopic pupil size were studied in 2 458 e...AIM: To study the distribution of ocular higher-order aberrations(HOAs) and mesopic pupil size in individuals screened for refractive surgery. · METHODS: Ocular HOAs and mesopic pupil size were studied in 2 458 eyes of 1 240 patients with myopia, myopic astigmatism and compound myopic astigmatism and 215 eyes of 110 patients with hyperopia, hyperopic astigmatism and compound hyperopic astigmatism using the Zywave aberrometer (Busch& Lomb). All patients had correctable refractive errors without a history of refractive surgery or underlying diseases. Root-mean-square values of HOAs, total spherical aberration, total coma and mesopic pupil size were analyzed. Ocular HOAs were measured across a ≥ 6.0 mm pupil, and pupil size measurements were performed under the mesopic condition. · RESULTS: The mean values of HOAs, total spherical aberration and total coma in the myopic group were 0.369 μm, ±0.233, 0.133±0.112μm and 0.330±0.188μm, respectively. In the hyperopic group the mean values of HOAs, total spherical aberration and total coma were 0.418μm±0.214, 0.202±0.209μm and 0.343±0.201μm, respectively. Hyperopes showed greater total HOAs (P <0.01) and total spherical aberration (P <0.01) compared to myopes. In age-matched analysis, only the amount of total spherical aberration was higher in the hyperopic group (P =0.05). Mesopic pupil size in the myopic group was larger (P ≤0.05). · CONCLUSION: The results suggested that significant levels of HOAs were found in both groups which are important for planning refractive surgeries on Iranians. There were significantly higher levels of total spherical aberration in hyperopes compared to myopes. Mesopic pupil size was larger in myopic group.展开更多
AIM:To explore a simple and low-cost self-made disposable flexible iris retractor and study its clinical efficacy and safety in small pupil phacoemulsification.METHODS:Polyproplyenesutureandscalpacupuncture were used ...AIM:To explore a simple and low-cost self-made disposable flexible iris retractor and study its clinical efficacy and safety in small pupil phacoemulsification.METHODS:Polyproplyenesutureandscalpacupuncture were used to make iris retractor.A prospective study were carried on 50 patients(50 eyes)with a maximally dilated pupil size of 2.5-4.0 mm which underwent phacoemulsification using this self-made iris retractor.Another 50 cases of phacoemulsification with normal pupil size sever as control group.The mean operation time,ultrasound time and ultrasonic power,volume of irrigation fluid were documented intraoperatively.The visual acuity,pupil size and complication were observed on 1d,1wk,1mo and 1y after operation.Corneal endothelial cell was measured at 1mo postoperatively.·RESULT:Pupils could be expanded to approximately4.5-5.5 mm with our self-made iris retractor in operation.No serious postoperative complication was found.Most(88%)of the pupils returned round or oval shape,light reflex restored to varying degrees at the first day after surgery.Best corrected visual acuity stabilized in 37 eyes(74%)at one day,in 43 eyes(86%)at one week,in 44eyes(88%)at one month and 46 eyes(92%)at one year.Compared with the control,more time was needed to complete the operation in the small pupil group.There was no significant difference of the mean ultrasound time,ultrasonic power,volume of irrigation fluid requiredand corneal endothelial cell loss in 1mo follow up between the two groups.CONCLUSION:Our self-made disposable flexible iris retractor could be easy obtained preoperatively or intraoperatively.It performed both safety and efficacy in our clinical trials.This simple self-made device has shown economic and practical values,especially in primary care hospital of the less developed districts.展开更多
AIM:To explore the photopic pupil size behavior in myopic children undergoing overnight orthokeratology(ortho-k)over 1-year period and its effects on the axial elongation.METHODS:A total of 202 Chinese myopic children...AIM:To explore the photopic pupil size behavior in myopic children undergoing overnight orthokeratology(ortho-k)over 1-year period and its effects on the axial elongation.METHODS:A total of 202 Chinese myopic children were enrolled in this prospective clinical trial.Ninetyfive subjects in ortho-k group and eighty-eight subjects in spectacle group completed the 1-year study.Axial length(AL)was measured before enrollment and every 6mo after the start of ortho-k.The photopic pupil diameter(PPD)was determined using the Pentacam AXL and measured in an examination room with lighting of 300-310 Lx.Stepwise multiple linear regression analysis was used to identify variables contribution to axial elongation.RESULTS:Compared with spectacle group,the average 1-year axial elongation was significantly slower in the ortho-k group(0.25±0.27 vs 0.44±0.23 mm,P<0.0001).In ortho-k group,PPDs significantly decreased from 4.21±0.62 mm to 3.94±0.53 mm after 1mo of lens wear(P=0.001,Bonferroni correction)and the change lasts for 3-month visit.No significantly change during the other follow-up visits was found(P>0.05,Bonferroni correction).The 4.81 mm PPD may be a possible cutoff point in the ortho-k group.Subjects with PPD below or equal to 4.81 mm tended to have smaller axial elongation compared to subjects with PPD above 4.81 mm after 1-year period(t=-3.09,P=0.003).In ortho-k group,univariate analyses indicated that those with older age,greater degree of myopia,longer AL,smaller baseline PPD(PPDbaseline)experienced a smaller change in AL.In multivariate analyses,older age,greater AL and smaller PPDbaseline were associated with smaller increases in AL.In spectacle group,PPD tended to be stable(P>0.05,Bonferroni correction)and did not affect axial growth.CONCLUSION:PPDs experience significantly decreases at 1-month and 3-month ortho-k treatment.Children with smaller PPD tend to experience slower axial elongation and may benefit more from ortho-k.展开更多
AIM: To analytically assess the effect of pupil size upon the refractive power distributions of different designs of multifocal contact lenses.METHODS: Two multifocal contact lenses of center-near design and one mul...AIM: To analytically assess the effect of pupil size upon the refractive power distributions of different designs of multifocal contact lenses.METHODS: Two multifocal contact lenses of center-near design and one multifocal contact lens of center-distance design were used in this study. Their power profiles were measured using the NIMO TR1504 device (LAMBDA-X, Belgium). Based on their power profiles, the power distribution was assessed as a function of pupil size. For the high addition lenses, the resulting refractive power as a function of viewing distance (far, intermediate, and near) and pupil size was also analyzed.RESULTS: The power distribution of the lenses was affected by pupil size differently. One of the lenses showed a significant spread in refractive power distribution, from about ?3 D to 0 D. Generally, the power distribution of the lenses expanded as the pupil diameter became greater. The surface of the lens dedicated for each distance varied substantially with the design of the lens.CONCLUSION: In an experimental basis, our results show how the lenses power distribution is affected by the pupil size and underlined the necessity of careful evaluation of the patient’s visual needs and the optical properties of a multifocal contact lens for achieving the optimal visual outcome.展开更多
By applying the wavefront coding technique to an optical system, the depth of focus can be greatly increased. Several complicated methods, such as Fisher Information based method, have already been taken to optimize f...By applying the wavefront coding technique to an optical system, the depth of focus can be greatly increased. Several complicated methods, such as Fisher Information based method, have already been taken to optimize for the best pupil phase mask in ideal condition. Here one simple point spread function (PSF) based method with only the standard deviation method used to evaluate the PSF stability over the depth of focus is taken to optimize for the best coefficients of pupil phase mask in practical optical systems. Results of imaging simulations for optical systems with and without pupil phase mask are presented, and the sharpness of image is calculated for comparison. The optimized results showed better and much more stable imaging quality over the original system without changing the position of the image plane.展开更多
pupils aged 9~12 years from six primary schools were cross-sectionally investigated on the psychological disorders with Conner Scale and EPQ. The results showed that the incidence of psychological disorders was 18. 2...pupils aged 9~12 years from six primary schools were cross-sectionally investigated on the psychological disorders with Conner Scale and EPQ. The results showed that the incidence of psychological disorders was 18. 2%,with 21. 3% in male and 15. 5% in female. The incidehees were significantly difrerent between male and remal (P<0. 05). The incidences or learning difficulty,hyperactivity and impulsive behavior were 8. 2%, 5. 3%,and 5.3% respectively.The family factors influencing the psychological disorders were the pupils'birth problems,the relationship between the pupils and their parents, and the parents'inappropriate prospect for the pupils.The investigation also found that the pupils with psychological disorders had more poor experiences or their family and school and more of them had obvious personality tendencies towards unstability or emotion,eccentricity and social immaturity as compared with the normal pupils. The effective measures to promote pupils'psychological health were suggested in this article.展开更多
·AIM:To study the relationship between corneal white-to- white (WTW) distance and mesopic pupil diameter. ·METHODS:This study is composed of 30 cases that underwent photorefractive keratotomy (PRK). Pupil si...·AIM:To study the relationship between corneal white-to- white (WTW) distance and mesopic pupil diameter. ·METHODS:This study is composed of 30 cases that underwent photorefractive keratotomy (PRK). Pupil size measurements were performed with Schwind ORK wavefront analyzer in mesopic conditions. WTW distance was measured with a measuring caliper. Also, A-scan ultrasound examination was performed in all patients. The relationship among the mesopic pupil diameter and age, sex, axial length, lens thickness, anterior chamber depth(ACD), horizontal WTW distance, vertical WTW distance, spherical equivalent, and average keratometry were analyzed with univariate and multivariate regression analysis. ·RESULTS:Mean pupil diameter was (6.39±0.80)mm (range:3.70mm to 7.73mm. Horizontal WTW distance measurements were between 11.00mm and 12.50mm and mean horizontal WTW distance was (11.79±0.43)mm. On the other hand, vertical WTW distances ranged between 10.00mm and 13.00mm, and their mean was(11.42±0.72)mm. Bivariate correlation between pupil diameter and other variables showed that the axial length, ACD, spherical equivalent, and horizontal WTW distance had a moderate correlation with mesopic pupil diameter. Multiple regression analysis revealed that spherical equivalent and horizontal WTW distances were significantly associated with mesopic pupil diameter (R =0.598, R 2=0.358 P =0.02). ·CONCLUSION:This study shows that mesopic pupil diameter is closely related to horizontal WTW distance. These two factors must be taken in consideration together in preoperative ablation zone planning.展开更多
Many women feel a physical burden, which usually appears as a pain, during mammography. We examined the pain-related pupil dilation response during mammography. Twenty-four healthy women participated in the examinatio...Many women feel a physical burden, which usually appears as a pain, during mammography. We examined the pain-related pupil dilation response during mammography. Twenty-four healthy women participated in the examination. They were randomly assigned to water group or sucrose group. Water group and sucrose group ingested distilled water and a sucrose solution during mammography, respectively. Their pupil sizes were measured during mammography excluding X-ray irradiation. The subjective intensity of pain during mammography was also assessed using visual analogue scales (VAS). The mean pupil diameter was 2.99 mm in relaxation phase before mammography, while it was 3.15 mm in a few seconds after breast compression (pressure phase). The difference between the two was statistically significant (p p < 0.01). These results suggest that we may be able to assess objectively the degree of pain associated with mammography and sweet taste stimuli may be effective to alleviate a women’s burden received during mammography.展开更多
AIM:To determine the agreement and repeatability of the pupil measurement obtained with VIP-200(Neuroptics),Power Ref II(Plusoptix),WAM-5500(Grand Seiko) and study the effects of instrument design on pupillomet...AIM:To determine the agreement and repeatability of the pupil measurement obtained with VIP-200(Neuroptics),Power Ref II(Plusoptix),WAM-5500(Grand Seiko) and study the effects of instrument design on pupillometry.METHODS:Forty patients were measured twice in low,mid and high mesopic.Repeatability was analyzed with the within-subject standard deviation(Sw) and paired t-tests.Agreement was studied with Bland-Altman plots and repeated measures ANOVA.Instrument design analysis consisted on measuring pupil size with Power Ref II simulating monocular and binocular conditions as well as with proximity cues and without proximity cues.RESULTS:The mean difference(±standard deviation) between test-retest for low,mid and high mesopic conditions were,respectively:-0.09(±0.16),-0.05(±0.18) and-0.08(±0.23) mm for Neuroptics,-0.05(±0.17),-0.12(±0.23) and-0.17(±0.34) mm for WAM-5500,-0.04(±0.27),-0.13(±0.37) and-0.11(±0.28) mm for Power Ref II.Regarding agreement with Neuroptics,the mean difference for low,mid and high mesopic conditions were,respectively:-0.48(±0.35),-0.83(±0.52) and-0.38(±0.56) mm for WAM-5500,-0.28(±0.56),-0.70(±0.55) and-0.61(±0.54) mm for Power Ref II.The mean difference of binocular minus monocular pupil measurements was:-0.83(±0.87) mm;and with proximity cues minus without proximity cues was:-0.30(±0.77) mm.CONCLUSION:All the instruments show similar repeatability.In all illumination conditions,agreement of Neuroptics with WAM-5500 and Power Ref II is not good enough,which can be partially induced due to their open field design.展开更多
This paper proposes a simple method to achieve the optical transfer function of a circular pupil wavefront coding system with a separable phase mask in Cartesian coordinates. Based on the stationary phase method, the ...This paper proposes a simple method to achieve the optical transfer function of a circular pupil wavefront coding system with a separable phase mask in Cartesian coordinates. Based on the stationary phase method, the optical transfer function of the circular pupil system can be easily obtained from the optical transfer function of the rectangular pupil system by modifying the cut-off frequency and the on-axial modulation transfer function. Finally, a system with a cubic phase mask is used as an example to illustrate the way to achieve the optical transfer function of the circular pupil system from the rectangular pupil system.展开更多
AIM: To evaluate the value of ultra-wide field(UWF) imaging in the management of traumatic retinopathy under the condition of corneal scar or fixed small pupil after complicated ocular trauma. METHODS: Twenty-eigh...AIM: To evaluate the value of ultra-wide field(UWF) imaging in the management of traumatic retinopathy under the condition of corneal scar or fixed small pupil after complicated ocular trauma. METHODS: Twenty-eight patients(28 eyes) with complicated ocular trauma were enrolled in the study from June 2016 to May 2017, including 19 males and 9 females with age ranged from 11 to 64(43.42±12.62)y. All patients were treated with secondary vitrectomy after emergency operation for wound repair of open ocular trauma. Direct ophthalmoscopy and 45-degree fundus photography were taken at each time point of follow up for comparison of findings with UWF images. Routine eye examination including visual acuity, intraocular pressure, slit lamp examination were performed and analyzed as well.RESULTS: Among the 28 traumatized eyes, the positive rate for identification of traumatic retinopathed was 32.1%(9 cases), 14.9%(5 cases), and 85.7%(24 cases) with direct ophthalmoscopy, 45-degree fundus photography, and UWF imaging, respectively. The detective rate of UWF imaging under the condition of corneal scar or fixed small pupil was statistically greater than that of 45-degree fundus photography and direct ophthalmoscopy(Bonferroni correction, P〈0.001). UWF image was obtained in 19 eyes with opaque corneal scar, otherwise their fundus could not be seen by conventional methods. The additional findings of traumatic retinopathies by UWF imaging included periretinal membranes or pre-retinal proliferating strip, retinal holes, hemorrhage in the vitreous or sub-retinal space.CONCLUSION: UWF imaging is superior to traditional fundus photography in the evaluation of traumatic retinopathies under the condition of corneal scar or fixed small pupil after complicated ocular trauma.展开更多
AIMTo evaluate the characteristics of pupillo-accommodative functions in patients with idiopathic tonic pupil according to the time of onset, gender, and age.
基金funded by Researchers Supporting Program at King Saud University (RSPD2023R809).
文摘Pupil dynamics are the important characteristics of face spoofing detection.The face recognition system is one of the most used biometrics for authenticating individual identity.The main threats to the facial recognition system are different types of presentation attacks like print attacks,3D mask attacks,replay attacks,etc.The proposed model uses pupil characteristics for liveness detection during the authentication process.The pupillary light reflex is an involuntary reaction controlling the pupil’s diameter at different light intensities.The proposed framework consists of two-phase methodologies.In the first phase,the pupil’s diameter is calculated by applying stimulus(light)in one eye of the subject and calculating the constriction of the pupil size on both eyes in different video frames.The above measurement is converted into feature space using Kohn and Clynes model-defined parameters.The Support Vector Machine is used to classify legitimate subjects when the diameter change is normal(or when the eye is alive)or illegitimate subjects when there is no change or abnormal oscillations of pupil behavior due to the presence of printed photograph,video,or 3D mask of the subject in front of the camera.In the second phase,we perform the facial recognition process.Scale-invariant feature transform(SIFT)is used to find the features from the facial images,with each feature having a size of a 128-dimensional vector.These features are scale,rotation,and orientation invariant and are used for recognizing facial images.The brute force matching algorithm is used for matching features of two different images.The threshold value we considered is 0.08 for good matches.To analyze the performance of the framework,we tested our model in two Face antispoofing datasets named Replay attack datasets and CASIA-SURF datasets,which were used because they contain the videos of the subjects in each sample having three modalities(RGB,IR,Depth).The CASIA-SURF datasets showed an 89.9%Equal Error Rate,while the Replay Attack datasets showed a 92.1%Equal Error Rate.
文摘AIM:To establish pupil diameter measurement algorithms based on infrared images that can be used in real-world clinical settings.METHODS:A total of 188 patients from outpatient clinic at He Eye Specialist Shenyang Hospital from Spetember to December 2022 were included,and 13470 infrared pupil images were collected for the study.All infrared images for pupil segmentation were labeled using the Labelme software.The computation of pupil diameter is divided into four steps:image pre-processing,pupil identification and localization,pupil segmentation,and diameter calculation.Two major models are used in the computation process:the modified YoloV3 and Deeplabv 3+models,which must be trained beforehand.RESULTS:The test dataset included 1348 infrared pupil images.On the test dataset,the modified YoloV3 model had a detection rate of 99.98% and an average precision(AP)of 0.80 for pupils.The DeeplabV3+model achieved a background intersection over union(IOU)of 99.23%,a pupil IOU of 93.81%,and a mean IOU of 96.52%.The pupil diameters in the test dataset ranged from 20 to 56 pixels,with a mean of 36.06±6.85 pixels.The absolute error in pupil diameters between predicted and actual values ranged from 0 to 7 pixels,with a mean absolute error(MAE)of 1.06±0.96 pixels.CONCLUSION:This study successfully demonstrates a robust infrared image-based pupil diameter measurement algorithm,proven to be highly accurate and reliable for clinical application.
文摘The pupil recognition method is helpful in many real-time systems,including ophthalmology testing devices,wheelchair assistance,and so on.The pupil detection system is a very difficult process in a wide range of datasets due to problems caused by varying pupil size,occlusion of eyelids,and eyelashes.Deep Convolutional Neural Networks(DCNN)are being used in pupil recognition systems and have shown promising results in terms of accuracy.To improve accuracy and cope with larger datasets,this research work proposes BOC(BAT Optimized CNN)-IrisNet,which consists of optimizing input weights and hidden layers of DCNN using the evolutionary BAT algorithm to efficiently find the human eye pupil region.The proposed method is based on very deep architecture and many tricks from recently developed popular CNNs.Experiment results show that the BOC-IrisNet proposal can efficiently model iris microstructures and provides a stable discriminating iris representation that is lightweight,easy to implement,and of cutting-edge accuracy.Finally,the region-based black box method for determining pupil center coordinates was introduced.The proposed architecture was tested using various IRIS databases,including the CASIA(Chinese academy of the scientific research institute of automation)Iris V4 dataset,which has 99.5%sensitivity and 99.75%accuracy,and the IIT(Indian Institute of Technology)Delhi dataset,which has 99.35%specificity and MMU(Multimedia University)99.45%accuracy,which is higher than the existing architectures.
文摘The objective of this study was to experimentally evaluate children’s daily food memory and eating habits.The study found that the gender and school location had an impact on the nutritional condition of primary school students as well as the school food scheme.The investigations were based on three hypotheses and three research questions.In this study,the Eating Habits and Daily Dietary Recall Scale was the tool utilized to gather data(EPDDRS).Four experts—three from the department of vocational education and one lecturer in test and measurement evaluation—validated the instrument’s face.The dependability indices of EPDDRS were calculated using Cronbach’s Alpha.While delivering the instruments,the researcher used the direct administration and retrieval approach.58 instructors and a sample size of 1240 students were selected using a systematic random selection approach.The obtained data was examined using mean and standard deviation to address the research objectives,and the null hypotheses were tested using t-test statistics and Analysis of variance(ANOVA)at the 0.05 level of significance.The main conclusions of this study were that the school meal program had a favorable impact on the students’nutritional status.Also,a balanced ration of nutrient-dense meals that were suitably varied was supplied for the students via the school food program.Also,the findings revealed a substantial difference in the mean assessments of male and female students about their eating patterns.On the school meal program’s dietary recall list,students from high,middle,and low socioeconomic status differ significantly.Recommendations were given to the government,schools,and parents based on the study’s findings.The study’s shortcomings were discussed,and recommendations for more research were made.
基金This research was funded by“TAIF UNIVERSITY RESEARCHERS SUPPORTING PROJECT,grant number TURSP-2020/345”,Taif University,Taif,Saudi Arabia.
文摘Recently,many researchers have tried to develop a robust,fast,and accurate algorithm.This algorithm is for eye-tracking and detecting pupil position in many applications such as head-mounted eye tracking,gaze-based human-computer interaction,medical applications(such as deaf and diabetes patients),and attention analysis.Many real-world conditions challenge the eye appearance,such as illumination,reflections,and occasions.On the other hand,individual differences in eye physiology and other sources of noise,such as contact lenses or make-up.The present work introduces a robust pupil detection algorithm with and higher accuracy than the previous attempts for real-time analytics applications.The proposed circular hough transform with morphing canny edge detection for Pupillometery(CHMCEP)algorithm can detect even the blurred or noisy images by using different filtering methods in the pre-processing or start phase to remove the blur and noise and finally the second filtering process before the circular Hough transform for the center fitting to make sure better accuracy.The performance of the proposed CHMCEP algorithm was tested against recent pupil detection methods.Simulations and results show that the proposed CHMCEP algorithm achieved detection rates of 87.11,78.54,58,and 78 according to´Swirski,ExCuSe,Else,and labeled pupils in the wild(LPW)data sets,respectively.These results show that the proposed approach performs better than the other pupil detection methods by a large margin by providing exact and robust pupil positions on challenging ordinary eye pictures.
基金This research was funded by the Science and Technology Support Plan Project of Hebei Province(grant numbers 17210803D and 19273703D)the Science and Technology Spark Project of the Hebei Seismological Bureau(grant number DZ20180402056)+1 种基金the Education Department of Hebei Province(grant number QN2018095)the Polytechnic College of Hebei University of Science and Technology.
文摘Human eye detection has become an area of interest in the field of computer vision with an extensive range of applications in human-computer interaction,disease diagnosis,and psychological and physiological studies.Gaze-tracking systems are an important research topic in the human-computer interaction field.As one of the core modules of the head-mounted gaze-tracking system,pupil positioning affects the accuracy and stability of the system.By tracking eye movements to better locate the center of the pupil,this paper proposes a method for pupil positioning based on the starburst model.The method uses vertical and horizontal coordinate integral projections in the rectangular region of the human eye for accurate positioning and applies a linear interpolation method that is based on a circular model to the reflections in the human eye.In this paper,we propose a method for detecting the feature points of the pupil edge based on the starburst model,which clusters feature points and uses the RANdom SAmple Consensus(RANSAC)algorithm to perform ellipse fitting of the pupil edge to accurately locate the pupil center.Our experimental results show that the algorithm has higher precision,higher efficiency and more robustness than other algorithms and excellent accuracy even when the image of the pupil is incomplete.
文摘for the past few decades,the way to achieve good teacher-pupil rapport in the classroom has been at the center of heated debate all over the world.All teachers should provide a good studying environment for pupils.This paper will focus on four parts to discuss this issue.
文摘A great earthquake broke out in WenChuan. A lot of people were killed, but somany people were rescused by soldiers.Here are stories about three recused pupils.Langzhen, aged three, was rescusedby the soldiers after being buried in ruinsfor 10 hours.
文摘AIM: To study the distribution of ocular higher-order aberrations(HOAs) and mesopic pupil size in individuals screened for refractive surgery. · METHODS: Ocular HOAs and mesopic pupil size were studied in 2 458 eyes of 1 240 patients with myopia, myopic astigmatism and compound myopic astigmatism and 215 eyes of 110 patients with hyperopia, hyperopic astigmatism and compound hyperopic astigmatism using the Zywave aberrometer (Busch& Lomb). All patients had correctable refractive errors without a history of refractive surgery or underlying diseases. Root-mean-square values of HOAs, total spherical aberration, total coma and mesopic pupil size were analyzed. Ocular HOAs were measured across a ≥ 6.0 mm pupil, and pupil size measurements were performed under the mesopic condition. · RESULTS: The mean values of HOAs, total spherical aberration and total coma in the myopic group were 0.369 μm, ±0.233, 0.133±0.112μm and 0.330±0.188μm, respectively. In the hyperopic group the mean values of HOAs, total spherical aberration and total coma were 0.418μm±0.214, 0.202±0.209μm and 0.343±0.201μm, respectively. Hyperopes showed greater total HOAs (P <0.01) and total spherical aberration (P <0.01) compared to myopes. In age-matched analysis, only the amount of total spherical aberration was higher in the hyperopic group (P =0.05). Mesopic pupil size in the myopic group was larger (P ≤0.05). · CONCLUSION: The results suggested that significant levels of HOAs were found in both groups which are important for planning refractive surgeries on Iranians. There were significantly higher levels of total spherical aberration in hyperopes compared to myopes. Mesopic pupil size was larger in myopic group.
文摘AIM:To explore a simple and low-cost self-made disposable flexible iris retractor and study its clinical efficacy and safety in small pupil phacoemulsification.METHODS:Polyproplyenesutureandscalpacupuncture were used to make iris retractor.A prospective study were carried on 50 patients(50 eyes)with a maximally dilated pupil size of 2.5-4.0 mm which underwent phacoemulsification using this self-made iris retractor.Another 50 cases of phacoemulsification with normal pupil size sever as control group.The mean operation time,ultrasound time and ultrasonic power,volume of irrigation fluid were documented intraoperatively.The visual acuity,pupil size and complication were observed on 1d,1wk,1mo and 1y after operation.Corneal endothelial cell was measured at 1mo postoperatively.·RESULT:Pupils could be expanded to approximately4.5-5.5 mm with our self-made iris retractor in operation.No serious postoperative complication was found.Most(88%)of the pupils returned round or oval shape,light reflex restored to varying degrees at the first day after surgery.Best corrected visual acuity stabilized in 37 eyes(74%)at one day,in 43 eyes(86%)at one week,in 44eyes(88%)at one month and 46 eyes(92%)at one year.Compared with the control,more time was needed to complete the operation in the small pupil group.There was no significant difference of the mean ultrasound time,ultrasonic power,volume of irrigation fluid requiredand corneal endothelial cell loss in 1mo follow up between the two groups.CONCLUSION:Our self-made disposable flexible iris retractor could be easy obtained preoperatively or intraoperatively.It performed both safety and efficacy in our clinical trials.This simple self-made device has shown economic and practical values,especially in primary care hospital of the less developed districts.
基金Supported by the Natural Science Foundation of Shanghai(No.18ZR1435700)Clinical Research Project of Shanghai Health and Family Planning Committee(No.201840199)。
文摘AIM:To explore the photopic pupil size behavior in myopic children undergoing overnight orthokeratology(ortho-k)over 1-year period and its effects on the axial elongation.METHODS:A total of 202 Chinese myopic children were enrolled in this prospective clinical trial.Ninetyfive subjects in ortho-k group and eighty-eight subjects in spectacle group completed the 1-year study.Axial length(AL)was measured before enrollment and every 6mo after the start of ortho-k.The photopic pupil diameter(PPD)was determined using the Pentacam AXL and measured in an examination room with lighting of 300-310 Lx.Stepwise multiple linear regression analysis was used to identify variables contribution to axial elongation.RESULTS:Compared with spectacle group,the average 1-year axial elongation was significantly slower in the ortho-k group(0.25±0.27 vs 0.44±0.23 mm,P<0.0001).In ortho-k group,PPDs significantly decreased from 4.21±0.62 mm to 3.94±0.53 mm after 1mo of lens wear(P=0.001,Bonferroni correction)and the change lasts for 3-month visit.No significantly change during the other follow-up visits was found(P>0.05,Bonferroni correction).The 4.81 mm PPD may be a possible cutoff point in the ortho-k group.Subjects with PPD below or equal to 4.81 mm tended to have smaller axial elongation compared to subjects with PPD above 4.81 mm after 1-year period(t=-3.09,P=0.003).In ortho-k group,univariate analyses indicated that those with older age,greater degree of myopia,longer AL,smaller baseline PPD(PPDbaseline)experienced a smaller change in AL.In multivariate analyses,older age,greater AL and smaller PPDbaseline were associated with smaller increases in AL.In spectacle group,PPD tended to be stable(P>0.05,Bonferroni correction)and did not affect axial growth.CONCLUSION:PPDs experience significantly decreases at 1-month and 3-month ortho-k treatment.Children with smaller PPD tend to experience slower axial elongation and may benefit more from ortho-k.
基金Supported by the AGEYE project(No.608049)the Marie Curie Initial Training Network program(No.FP7-PEOPLE-2013-ITN)the European Commission,Brussels,Belgium and by an Atraccióde Talent(University of Valencia)research scholarship granted to Antonio J.Deláguila-Carrasco(No.UV-INV-PREDOC14-179135)
文摘AIM: To analytically assess the effect of pupil size upon the refractive power distributions of different designs of multifocal contact lenses.METHODS: Two multifocal contact lenses of center-near design and one multifocal contact lens of center-distance design were used in this study. Their power profiles were measured using the NIMO TR1504 device (LAMBDA-X, Belgium). Based on their power profiles, the power distribution was assessed as a function of pupil size. For the high addition lenses, the resulting refractive power as a function of viewing distance (far, intermediate, and near) and pupil size was also analyzed.RESULTS: The power distribution of the lenses was affected by pupil size differently. One of the lenses showed a significant spread in refractive power distribution, from about ?3 D to 0 D. Generally, the power distribution of the lenses expanded as the pupil diameter became greater. The surface of the lens dedicated for each distance varied substantially with the design of the lens.CONCLUSION: In an experimental basis, our results show how the lenses power distribution is affected by the pupil size and underlined the necessity of careful evaluation of the patient’s visual needs and the optical properties of a multifocal contact lens for achieving the optimal visual outcome.
文摘By applying the wavefront coding technique to an optical system, the depth of focus can be greatly increased. Several complicated methods, such as Fisher Information based method, have already been taken to optimize for the best pupil phase mask in ideal condition. Here one simple point spread function (PSF) based method with only the standard deviation method used to evaluate the PSF stability over the depth of focus is taken to optimize for the best coefficients of pupil phase mask in practical optical systems. Results of imaging simulations for optical systems with and without pupil phase mask are presented, and the sharpness of image is calculated for comparison. The optimized results showed better and much more stable imaging quality over the original system without changing the position of the image plane.
文摘pupils aged 9~12 years from six primary schools were cross-sectionally investigated on the psychological disorders with Conner Scale and EPQ. The results showed that the incidence of psychological disorders was 18. 2%,with 21. 3% in male and 15. 5% in female. The incidehees were significantly difrerent between male and remal (P<0. 05). The incidences or learning difficulty,hyperactivity and impulsive behavior were 8. 2%, 5. 3%,and 5.3% respectively.The family factors influencing the psychological disorders were the pupils'birth problems,the relationship between the pupils and their parents, and the parents'inappropriate prospect for the pupils.The investigation also found that the pupils with psychological disorders had more poor experiences or their family and school and more of them had obvious personality tendencies towards unstability or emotion,eccentricity and social immaturity as compared with the normal pupils. The effective measures to promote pupils'psychological health were suggested in this article.
文摘·AIM:To study the relationship between corneal white-to- white (WTW) distance and mesopic pupil diameter. ·METHODS:This study is composed of 30 cases that underwent photorefractive keratotomy (PRK). Pupil size measurements were performed with Schwind ORK wavefront analyzer in mesopic conditions. WTW distance was measured with a measuring caliper. Also, A-scan ultrasound examination was performed in all patients. The relationship among the mesopic pupil diameter and age, sex, axial length, lens thickness, anterior chamber depth(ACD), horizontal WTW distance, vertical WTW distance, spherical equivalent, and average keratometry were analyzed with univariate and multivariate regression analysis. ·RESULTS:Mean pupil diameter was (6.39±0.80)mm (range:3.70mm to 7.73mm. Horizontal WTW distance measurements were between 11.00mm and 12.50mm and mean horizontal WTW distance was (11.79±0.43)mm. On the other hand, vertical WTW distances ranged between 10.00mm and 13.00mm, and their mean was(11.42±0.72)mm. Bivariate correlation between pupil diameter and other variables showed that the axial length, ACD, spherical equivalent, and horizontal WTW distance had a moderate correlation with mesopic pupil diameter. Multiple regression analysis revealed that spherical equivalent and horizontal WTW distances were significantly associated with mesopic pupil diameter (R =0.598, R 2=0.358 P =0.02). ·CONCLUSION:This study shows that mesopic pupil diameter is closely related to horizontal WTW distance. These two factors must be taken in consideration together in preoperative ablation zone planning.
文摘Many women feel a physical burden, which usually appears as a pain, during mammography. We examined the pain-related pupil dilation response during mammography. Twenty-four healthy women participated in the examination. They were randomly assigned to water group or sucrose group. Water group and sucrose group ingested distilled water and a sucrose solution during mammography, respectively. Their pupil sizes were measured during mammography excluding X-ray irradiation. The subjective intensity of pain during mammography was also assessed using visual analogue scales (VAS). The mean pupil diameter was 2.99 mm in relaxation phase before mammography, while it was 3.15 mm in a few seconds after breast compression (pressure phase). The difference between the two was statistically significant (p p < 0.01). These results suggest that we may be able to assess objectively the degree of pain associated with mammography and sweet taste stimuli may be effective to alleviate a women’s burden received during mammography.
基金Supported by the Spanish Ministry of Economy and Competitiveness under the grant DPI 2014-56850-R
文摘AIM:To determine the agreement and repeatability of the pupil measurement obtained with VIP-200(Neuroptics),Power Ref II(Plusoptix),WAM-5500(Grand Seiko) and study the effects of instrument design on pupillometry.METHODS:Forty patients were measured twice in low,mid and high mesopic.Repeatability was analyzed with the within-subject standard deviation(Sw) and paired t-tests.Agreement was studied with Bland-Altman plots and repeated measures ANOVA.Instrument design analysis consisted on measuring pupil size with Power Ref II simulating monocular and binocular conditions as well as with proximity cues and without proximity cues.RESULTS:The mean difference(±standard deviation) between test-retest for low,mid and high mesopic conditions were,respectively:-0.09(±0.16),-0.05(±0.18) and-0.08(±0.23) mm for Neuroptics,-0.05(±0.17),-0.12(±0.23) and-0.17(±0.34) mm for WAM-5500,-0.04(±0.27),-0.13(±0.37) and-0.11(±0.28) mm for Power Ref II.Regarding agreement with Neuroptics,the mean difference for low,mid and high mesopic conditions were,respectively:-0.48(±0.35),-0.83(±0.52) and-0.38(±0.56) mm for WAM-5500,-0.28(±0.56),-0.70(±0.55) and-0.61(±0.54) mm for Power Ref II.The mean difference of binocular minus monocular pupil measurements was:-0.83(±0.87) mm;and with proximity cues minus without proximity cues was:-0.30(±0.77) mm.CONCLUSION:All the instruments show similar repeatability.In all illumination conditions,agreement of Neuroptics with WAM-5500 and Power Ref II is not good enough,which can be partially induced due to their open field design.
基金Project supported by the Natural Science Foundation of Zhejiang Province,China (Grant No. Y1110455)the Scientific Research Fund of Educational Department of Zhejiang Province,China (Grant No. Y200909691)the Science Foundation of Zhejiang Sci-Tech University (Grant No. 0913849-Y)
文摘This paper proposes a simple method to achieve the optical transfer function of a circular pupil wavefront coding system with a separable phase mask in Cartesian coordinates. Based on the stationary phase method, the optical transfer function of the circular pupil system can be easily obtained from the optical transfer function of the rectangular pupil system by modifying the cut-off frequency and the on-axial modulation transfer function. Finally, a system with a cubic phase mask is used as an example to illustrate the way to achieve the optical transfer function of the circular pupil system from the rectangular pupil system.
基金Supported by Sichuan Province Scientific Research Project of Institutions of Higher Education (No.2017ZRQN-108)
文摘AIM: To evaluate the value of ultra-wide field(UWF) imaging in the management of traumatic retinopathy under the condition of corneal scar or fixed small pupil after complicated ocular trauma. METHODS: Twenty-eight patients(28 eyes) with complicated ocular trauma were enrolled in the study from June 2016 to May 2017, including 19 males and 9 females with age ranged from 11 to 64(43.42±12.62)y. All patients were treated with secondary vitrectomy after emergency operation for wound repair of open ocular trauma. Direct ophthalmoscopy and 45-degree fundus photography were taken at each time point of follow up for comparison of findings with UWF images. Routine eye examination including visual acuity, intraocular pressure, slit lamp examination were performed and analyzed as well.RESULTS: Among the 28 traumatized eyes, the positive rate for identification of traumatic retinopathed was 32.1%(9 cases), 14.9%(5 cases), and 85.7%(24 cases) with direct ophthalmoscopy, 45-degree fundus photography, and UWF imaging, respectively. The detective rate of UWF imaging under the condition of corneal scar or fixed small pupil was statistically greater than that of 45-degree fundus photography and direct ophthalmoscopy(Bonferroni correction, P〈0.001). UWF image was obtained in 19 eyes with opaque corneal scar, otherwise their fundus could not be seen by conventional methods. The additional findings of traumatic retinopathies by UWF imaging included periretinal membranes or pre-retinal proliferating strip, retinal holes, hemorrhage in the vitreous or sub-retinal space.CONCLUSION: UWF imaging is superior to traditional fundus photography in the evaluation of traumatic retinopathies under the condition of corneal scar or fixed small pupil after complicated ocular trauma.
文摘AIMTo evaluate the characteristics of pupillo-accommodative functions in patients with idiopathic tonic pupil according to the time of onset, gender, and age.