Improving Performance of Object Detection using the Mechanisms of Visual Recognition in Humans

Object recognition systems are usually trained and evaluated on high resolution images. However, in real world applications, it is common that the images have low resolutions or have small sizes. In this study, we first track the performance of the state-of-the-art deep object recognition network, Faster- RCNN, as a function of image resolution. The results reveals negative effects of low resolution images on recognition performance. They also show that different spatial frequencies convey different information about the objects in recognition process. It means multi-resolution recognition system can provides better insight into optimal selection of features that results in better recognition of objects. This is similar to the mechanisms of the human visual systems that are able to implement multi-scale representation of a visual scene simultaneously. Then, we propose a multi-resolution object recognition framework rather than a single-resolution network. The proposed framework is evaluated on the PASCAL VOC2007 database. The experimental results show the performance of our adapted multi-resolution Faster-RCNN framework outperforms the single-resolution Faster-RCNN on input images with various resolutions with an increase in the mean Average Precision (mAP) of 9.14% across all resolutions and 1.2% on the full-spectrum images. Furthermore, the proposed model yields robustness of the performance over a wide range of spatial frequencies

Modeling of unconfined compressive strength and Young's modulus of lime and cement stabilized clayey subgrade soil using Evolutionary Polynomial Regression (EPR)

In this study, the evolutionary polynomial regression (EPR) method has been employed to develop simple models with reasonable accuracy to predict the compressive strength and Young's modulus of the lime/cement stabilized clayey subgrade soil. For this purpose, the different specimens with the various cement and lime contents, at three moisture contents (dry side, wet side, and optimum moisture content) were fabricated and were cured for 7, 14, 21, 28 and, 60 days to conduct the unconfined compressive strength (UCS) test. According to the test results, a dataset consisting of 75 records for each additive was prepared. Results of this study show that the R2 value of the developed model for predicting UCS of cement-stabilized clay soil is equal to 0.96 and 0.95 for training and testing sets, respectively. These two values for lime-stabilized soil are 0.91 and 0.87, respectively. Moreover, the R2 for predicting Young's modulus of cement-stabilized clay soil is equal to 0.90 and 0.89 for training and testing set, respectively. These two values for predicting Young's modulus of lime-stabilized soil are 0.88 and 0.94, respectively. The sensitivity analysis showed that for the Portland cement stabilized clayey subgrade, the percentage of the Portland cement and moisture content are the most significant parameters for predicting the UCS and Young's modulus, respectively. In contrast, for the lime-stabilized clayey subgrade soil, the most important parameters are the moisture content and the UCS, respectively

Correlation between bone mineral density of jaws and skeletal sites in an Iranian population using dual X-ray energy absorptiometry

Background: The aim of the present study was to evaluate the relationship between the bone density of various regions of jaws and skeletal bones. Materials and Methods: A total of 110 patients with a mean age of 55.01 ± 10.77 years were selected for the purpose of the present descriptive study. Dual X-ray Energy Absorptiometry (DXA) was carried out to determine bone mineral density (BMD) of the femur and lumbar vertebrae. Then all the subjects underwent DXA of the jaw bones and BMD values were determined at four jaw regions. Data were analyzed by SPSS 16 statistical software, and the correlation between the various BMD values was determined by Pearson′s correlation coefficient. Results: The results showed that 42.7% of females had normal BMD values in the femur, and in vertebrae, 20% were osteopenic and 37.3% suffered from osteoporosis, with statistically significant differences in the BMD values of the jaws between the three above-mentioned groups (P < 0.001). There was an increasing tendency toward osteopenia and osteoporosis with age. There was a positive correlation between BMD values of the femur and lumbar vertebrae and those of all the jaw regions under study (P < 0.005). There was a negative correlation (P < 0.01) between age and the BMD values of the femur, lumbar vertebrae and anterior maxilla. Conclusion: The bone density of the maxilla and mandible and presence of osteoporosis or osteopenia in these bones might reflect the same problem in skeletal bones

Speech Intelligibility in Persian Children with Down Syndrome

Objectives: One of the most effective methods to describe speech disorders is the measurement of speech intelligibility. The speech intelligibility indicates the extent of acoustic signals that correctly speaker produces and hearer receives. The purpose of this study was to investigate the speech intelligibility in the Persian children with Down syndrome, age range was 3 to 5 years, who had spoken Persian. Methods: this cross- sectional study investigates 12 children (6 girls and 6 boys) with Down syndrome who had referred to speech therapy clinic in Hamadan city and 12 normal children (6 girls and 6 boys) who went to the kindergarten in Hamadan city. The pictures of speech intelligibility test (in Persian language) were used to collect speech samples of participants. The participant&rsquo;s voice was recorded by voice recorder and was investigated in two age groups. Results: The results of this study indicated the means of speech intelligibility was 92.25 for normal children and 35.08 for children with Down syndrome. The correlation between age and speech intelligibility for normal children was 0.866 and for children with Down syndrome was 0.352. The mean of speech intelligibility 2 for normal boys was 93 and for normal girls 91.5 and for boys with Down syndrome 34.66 and for girls with Down syndrome 35.5. Discussion: The difference between normal children and children with Down syndrome was Significant. One of the factors that affects speech intelligibility for children with Down syndrome is difficulty with voluntarily programming, combining, organizing, and sequencing the movements necessary for speech

Serum biochemical profile of sheep fed olive-pulp silage for extended period

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Vestibular Dysfunctions in Cochlear Implant Patients; A Vestibular Evoked Myogenic Potential Study

Background and Aim: Vestibular evoked myogenic potential in response to click or short tone burst stimuli have been used as a clinical test for distinguish saccule and inferior vestibular nerve diseases. Different studies show that cochlear implant could have inverse effects on vestibular structures. We aimed to investigate vestibular evoked myogenic potential in unilateral cochlear implanted individuals in compare to normal individuals.Methods: Thirty-three unilateral cochlear implanted patients (mean age 19.96 years) and 30 normal hearing individuals (mean age 24-27 years) as control group were enrolled in this cross- sectional study. Absolute latencies and amplitudes of myogenic potential responses were measured and compared in both groups.Results: Myogenic potential recorded in both ears of all controls were normal. No response could be recorded in 16 patients (48.48%) from both ears. In three patients, responses were recorded in both ears though the amplitude of waves was reduced in implanted ear. Unilateral response could be recorded in 14 patients only in their non-implanted ear.Conclusion: Vestibular evoked myogenic potential test is a useful tool for assessing saccular function in cochlear implant patients. Damages of osseous spiral lamina and basilar membrane after cochlear implantation could result in dysfunctions of vestibular organs specially saccule. It seems that saccule could be easily damaged after cochlear implantation. This would cause absence or reduced amplitudes in myogenic potential

Percentile Charts of Neonatal Blood Pressure Values at a Tertiary Iranian Hospital

Background: Blood pressure (BP) is an important vital sign and indicator of clinical stability. Therefore, the accurate measurement and interpretation of this physiological signal is essential for the optimal management of ill newborns. In this regard, the present study aimed to determine BP values and percentiles in stable newborns in the first weeks of life and evaluate the relevant factors.Methods: This prospective observational study was conducted on 320 term and preterm newborns between 26 and 42 weeks gestational age (GA) within 2015-2017. The exclusion criteria entailed: 1) birth asphyxia,2) preeclampsia, 3) gestational diabetes mellitus (GDM) type I, 4) illicit substance use, and 5) major congenital anomaly. The oscillometric technique was used for BP measurement and systolic and diastolic BPs were analyzed by regression analysis for various percentiles (5th to 95th).Results: The neonates in the current study consisted of 185 (57.8%) males and 135 (42.2%) females with mean (SD) birth weight of 2058.3±582.5grams. Mean (SD) gestational age was reported as 32.95(3.97) weeks. 69.1 % of neonates were delivered via cesarean section. Percentile charts (5th- 95th values) which were developed for systolic (SBP) and diastolic (DBP) demonstrated a steady rise on the respective days that were comparable between different groups. Term neonates were found to have higher BPs, compared to their preterm counterparts on the respective days. Moreover, the neonates who were delivered vaginally had higher mean BP values than neonates delivered via cesarean section.Conclusion: The current study provided normative BP values among neonates, especially in the first two weeks of life. Data presented in this study which include delivery-mode-specific BP percentile curves using an oscillometric method serve as a valuable reference for physicians in the management of newborns in the neonatal unit