Three-Dimensional Design of Axial Flow Compressor Blades Using the Ball-Spine Algorithm

Recently a new inverse design algorithm has been developed for the design of ducts, called ball-spine (BS). In the BS algorithm, the duct walls are considered as a set of virtual balls that can freely move along some specified directions, called ‘spines’. Initial geometry is guessed and the flow field is analyzed by a flow solver. Comparing the computed pressure distribution (CPD) with the target pressure distribution (TPD), new balls positions for the modified geometry are determined. This procedure is repeated until the target pressure is achieved. In the present work, the ball-spine algorithm is applied to three-dimensional design of axial compressor blades. The design procedure is tested on blades based on NACA65-410 and NACA65-610 profiles and the accuracy of the method is shown to be very good. As an application, the pressure distribution of the blade with NACA65-610 profiles is modified and the pressure gradient in the aft part of the blade is decreased and selected as target pressure distribution. The corresponding geometry which satisfies the target pressure is determined using the BS design algorithm

Biology of Parapodia sinaica (Lep.: Gelechiidae) in Qom province

Parapodia sinaica Frau. is among one of the important pests of tamarisk (Tamarix spp.) in Qom province. During 2000-2003, the biology of this pest was studied by periodic samplings of its different life stages every 15 days using light traps in natural tamarisk fields (Masileh region - Qom salt lake) and rearing some life stages in transparent dishes containing a tamarisk stem in laboratory conditions (50 ± 5% RH, 25 ± 1ºC and a photoperiod of 16L: 8D h.). P. sinaica overwinters as 4th or 5th larval instars in the galls. In early March, larvae change into pupa and the pupal period lasts 52 ± 5 and 44 ± 3 days in field and laboratory conditions, respectively. Flight peak of the adult moth took place in early May. The moth being fed on water and sugar survived 14 ± 3 days and preoviposition period lasted 2.3 ± 0.49 days. Average egg number deposited by a female in natural conditions was 32 ± 7. Oviposition period lasted 7.2 ± 0.83 days and incubation period of eggs was 29 ± 3 and 25 ± 2 days in the field and laboratory conditions, respectively. This insect has five larval instars and the mean developmental time of the first to the fifth larval instars were 63 ± 5, 46 ±.34, 44 ± 3.8, 50 ± 5.3 and 97 ± 6.2 days, respectively. The pest has one generation in a year. Larvae never feed on the wood but they feed on bark and cause die back of the branches in the end of the next year. Activity of this pest was also observed in Isfahan, Khuzestan, Qom and Yazd provinces

Robust Walking Using Peicewise Linear Spring

Having a direct impact on the energy efficiency has made the compliance a favorable element in the robotic systems. Moreover, legged system can benefit from compliance for stability, speed, adaptability and robustness. Recently, we have studied the effects of compliant spine in quadrupedal robots. We have observed that having nonlinearity in the spine compliance can set a better trade-off between speed and energy efficiency. Similar to the spine in quadruped robots, compliance at the hip joint of bipedal robots can also improve the walking performance such as robustness. Here, we test the efficacy of piecewise linear hip compliance for robust bipedal walking

Changes in Aflatoxin Content During the Processing of Vinegar Obtained From Grape

Mycotoxins are known to be one of the most important food contaminants that pose potential health risks to humans. This study aimed to investigate the changes in total aflatoxin (TAF) content during grape vinegar production. Different types of aflatoxins including aflatoxin B1 (AFB1 ), B2 (AFB2 ), G1 (AFG1 ), and G2 (AFG2 ) were spiked into washed grape samples in the level of 5 μg/kg. Then grape samples were converted to vinegar. After different stages of vinegar processing including juicing, alcoholic fermentation, acetic acid fermentation, and pasteurization, sampling was performed and the level of each aflatoxin was measured using high performance liquid chromatography with fluorescence detector (HPLC-FD). Among different processing steps, the pasteurization operation had the least effect on the removal of aflatoxin. After juicing, the amount of AFB1 , AFB2 , AFG1 and AFG2 decreased by 14%, 11.18%, 13.77%, and 18.56%, respectively. Alcoholic fermentation had the greatest effect on the removal of aflatoxin so that it could reduce the levels of AFB1 , AFB2 , AFG1 and AFG2 by 41.87%, 45.34%, 45.37%, and 46.52%, respectively. Overall, during processing and conversion of grapes to vinegar, the values of AFB1 , AFB2 , AFG1 and AFG2 were reduced by 76.20%, 71.06%, 69.26%, and 75.85%, respectively. Processing grapes to vinegar can have a significant effect on the aflatoxin reduction

Online learning of taskdriven object-based visual attention control

A biologically-motivated computational model for learning task-driven and objectbased visual attention control in interactive environments is proposed. Our model consists of three layers. First, in the early visual processing layer, most salient location of a scene is derived using the biased saliency-based bottom-up model of visual attention. Then a cognitive component in the higher visual processing layer performs an application specific operation like object recognition at the focus of attention. From this information, a state is derived in the decision making and learning layer. Online Learning of Task-driven Object-based Visual Attention Control Ali Borji Top-down attention is learned by the U-TREE Discussions and Conclusions An agent working in an environment receives information momentarily through its visual sensor. It should determine what to look for. For this we use RL to teach the agent simply look for the most task relevant and rewarding entity in the visual scene ( This layer controls both top-down visual attention and motor actions. The learning approach is an extension of the U-TREE algorithm [6] to the visual domain. Attention tree is incrementally built in a quasi-static manner in two phases (iterations): 1) RL-fixed phase and 2) Tree-fixed phase In each Tree-fixed phase, RL algorithm is executed for some episodes by Fig. 1. Proposed model for learning task-driven object-based visual attention control Example scenario: captured scene through the agents' visual sensor undergoes a biased bottom-up saliency detection operation and focus of attention (FOA) is determined. Object at the FOA is recognized (i.e. is either present or not in the scene), then the agent moves in its binary tree in the decision making and leaves. 100% correct policy was achieved. The object at the attended location is recognized by the hierarchical model of object recognition (HMAX) [3] M. Riesenhuber, T. Poggio, Hierarchical models of object recognition in cortex. Nature Neuroscience, 2(1999),11, 1019-1025. Basic saliency-based model of visual attention [1] is revised for the purpose of salient region selection (object detection) at this layer where norm(.) is the Euclidean distance between two points in an image. Saliency is the function which takes as input an image and a weight vector and returns the most salient location. t i is the location of target object in the i-th image. In each Tree-fixed phase, RL algorithm is executed for some episodes by following ε-greedy action selection strategy. In this phase, tree is hold fixed and the derived quadruples (s t , a t , r t+1 , s t+1 ) are only used for updating the Q-table: State discretization occurs in the RL-fixed phase where gathered experiences are used to refine aliased states. An object which minimizes aliasing the most is selected for braking an aliased leaf. Acknowledgement This work was funded by the school of cognitive sciences, IPM, Tehran, IRAN. scene), then the agent moves in its binary tree in the decision making and learning layer. This is done repetitively until it reaches a leaf node which determines its state. The best motor action is this state is performed. Outcome of this action over the world is evaluated by a critic and a reinforcement signal is fed back to the agent to update its internal representations (attention tree) and action selection strategy in a quasi-static manner. Following subsections discuss each layer of the model in detail

Five years of a single burn center experience with toxic epidermal necrolysis: retrospective study of causative drugs and the clinical outcome

Background: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare, but potentially life-threatening reactions to medications. Both conditions have significant morbidity and mortality. This study aimed to document the epidemiological features, aetiologies, treatment and clinical outcomes of such patients.Method: In this retrospective cross-sectional study the records of all patients with TEN treated for5 years in central Hospital, Mashhad, Iran were reviewed. Results: Thirty-four patients were studied with a mean age of 26.5 years. Mean age in the mortality and survivors groups was 33.6 and 25.3 years, respectively. Drugs accounted for all 34 cases were including Anti-convulsants (52.9%) other the most common implicated drug followed by antibiotics (26.5%), allopurinol (5.9%) and multiple drugs (anticonvulsants plus antibiotics) (14.7%). Antibiotics had the shortest interval between ingestion time and onset of symptoms. The mean ICU length of stay was 12.7 days, with a range of 1 to 30 days. The mean of SCORTEN was 2.3; it was 3.3 and 2.1 in the mortality and survivors group, respectively (P=0.001).All 34 TEN cases were given intravenous immunoglobulins (IVIG). Six patients with TEN died (17.6%). The highest mortality was found in the allopurinol group with 50%, whereas anticonvulsants and antibiotics had a mortality rate of 16.6% and 15.3%, respectively.Conclusion: Anti-convulsants especially Lamotrigine were the most frequently implicated drug, followed by antibiotics and allopurinol. IVIG was shown beneficial effects in TEN syndrome

Piecewise linear spine for speed-energy efficiency trade-off in quadruped robots

We compare the effects of linear and piecewise linear compliant spines on locomotion performance of quadruped robots in terms of energy efficiency and locomotion speed through a set of simulations and experiments. We first present a simple locomotion system that behaviorally resembles a bounding quadruped with flexible spine. Then, we show that robots with linear compliant spines have higher locomotion speed and lower cost of transportation in comparison with those with rigid spine. However, in linear case, optimal speed and minimum cost of transportation are attained at very different spine compliance values. Moreover, it is verified that fast and energy efficient locomotion can be achieved together when the spine flexibility is piecewise linear. Furthermore, it is shown that the robot with piecewise linear spine is more robust against changes in the load it carries. Superiority of piecewise linear spines over linear and rigid ones is additionally confirmed by simulating a quadruped robot in Webots and experiments on a crawling two-parts robot with flexible connection. (C) 2013 Elsevier B.V. All rights reserved

The Impact of an Instructional Model with Assistive Technology on Achievement Satisfaction of People with Physical-Motor Impairments

Background: The use of new technologies in education is a topic that has attracted the attention of educational experts over the past two decades. The purpose of this study was to investigate the effect of an instructional model enriched with assistive technology on the achievement satisfaction of people with physical-motor impairments in learning English. Methods: The research method is semi-experimental, with a pre-test/post-test design using a control group. The statistical population consisted of male individuals with physical mobility impairments studying at Imam Ali Educational Center in Tehran. To determine the sample size,Cohen’s (1986) table was used. Based on the sample size table, 16 people were selected. In this method, after drawing up a student list with a random number table, the sample was selected after checking criteria for entry and exit. The experimental group was trained in six sessions using an instructional model enriched with online and offline assistive technologies, and the control group was trained in the usual way. Results: The mean ± standard deviation (SD) for pre- and post-test in the experimental group were 75.50 ± 5.90 and 82.25 ± 6.29, respectively, and was 75.38 ± 11 and 77.37 ± 11.91 in the control group. The results of the analysis of covariance between adjusted means of both groups for variable of academic satisfaction show a significant difference between the two groups (F =20.06, P < 0.01). The effect size was 0.60. Conclusion: Using an instructional model enriched with assistive technology can be useful in teaching English to individuals with physical-motor impairments

Sport and Risk- Taking against Substance Abuse in students of Tehran High Schools

Substance abuse, violation and sexual behavior are the main reasons of fatality in adolescents and the youth. Most risky behaviors including cigarettes, alcohol, drugs and unsafe sexual contacts occur under the age of 18. Traditionally, sport is regarded as a means to encourage and develop healthy behaviors and a factor to protect and prevent risky behaviors. The present study studied 406 students including 271 male and 135 female students to compare the vulnerability of male and female athlete and non-athlete adolescents to risky behaviors such as smoking, drugs and alcohol. Iranian Adolescence Risk-Taking Scale (IARS) was used to measure the risk taking (Zadeh Mohammadi & Ahmadabadi, 2008). Those adolescents who have been a member of athletic teams had higher mean in subscale ‘drinking alcohol’. Those athletes who participated in provincial competitions and higher levels, those who engaged more than three sessions a week in sport teams and those athletes who attended sport camps had a higher mean. Also, there was no significant difference between individual and group sports. When explaining the higher levels of risk-taking in those who were members of athletic teams and clubs , factors such as duality, and the difficulty in playing the role of a student and an athlete simultaneously, camp condition, lack of sufficient control over members’ behaviors except when they are playing, peers’ collective norms, normative pressure to conform with various expectations of the team, lack of scientific attitude towards school athletic organizations in Iran, and concurrent influence of personality features like sensation and novelty sought in tendencies toward sport and risky behaviors can be taken into account