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Background and aims Asthma exacerbation is defined as an acute attack of shortness of breath with more than 25% decrease in morning peak flow compared to the baseline on 2 consecutive days, which requires immediate standard therapy. The majority of asthmatic patients are considered to be steroid-sensitive; however, corticosteroid-resistant asthma is a subset of asthma with poor response to corticosteroids and is responsible for frequent hospital admissions. In this study we aimed to compare the effects of two enhancing strategies, the nebulized ketamine and IV magnesium sulfate, in treatment of severe steroid resistant asthma. Materials and methods This double-blind randomized clinical trial was conducted on patients who presented to a referral clinic in Alborz, Iran. Using random allocation, patients were divided into two groups. The first group was treated with nebulized ketamine and the second group was treated with intravenous magnesium sulfate. Peak expiratory flow rates were assessed before the intervention, 30 and 60 min after the intervention and compared with the aid of SPSS software. Results The Peak expiratory flow rates before the intervention, 30 min and 60 min after the intervention was statistically significantly different in both ketamine and magnesium sulfate groups. Peak expiratory flow rates change between 0 and 60 min were 29.4 and 15.2% in the ketamine and magnesium sulfate group respectively. Although the ketamine group showed much higher increase in mean PEFR compared to the MgSO4 groups, there was no statistically significant difference across both groups. Conclusion Our study concluded that combined with standard therapy, both ketamine and IV magnesium sulfate are effective agents in the improvement of PEFR in patients with acute severe asthma that failed to respond to traditional therapies. However, there were no statistically significant difference between the two groups.

Transcranial direct current stimulation (tDCS) of the prefrontal cortex is known as a promising intervention in major depression disorder (MDD). However, limited information on predictors of therapeutic response to tDCS are available. This study aimed to investigate clinical and demographic predictors of therapeutic response in patients taking no medications. For this purpose, the required data were collected from 2 independent tDCS trials on 116 MDD patients. Accordingly, 84 patients underwent 10 sessions of 2 mA tDCS daily each one lasted for 20 min and 32 patients received 10 twice sessions of 2 mA tDCS daily each one lasted for 20 min. Anodal electrode was located over the left dorsolateral prefrontal cortex (DLPFC), and cathode was over the right supraorbital region. Depression symptoms and the underlying clinical dimensions were assessed using the Beck Depression Inventory (BDI-II) at baseline and after the tDCS treatment. Of the included 116 patients, 47.4% showed an antidepressant response. Results of logistic regression analysis showed that the reduction in BDI-II scores after tDCS was associated with the baseline values of cognitive-affective symptoms factor, loss of pleasure, loss of interest, and sleep problems. Pronounced sleep disturbances and cognitive-affective symptoms were identified as the potential clinical predictors of response to tDCS. However, more prospective tDCS studies are necessary to validate the predictive value of the derived model.

An overview on the history of Turkic language indicates that religious works have a special place in this field. In particular, a considerable part of prose works have religious content. At the same time with adoption of Islam by Turkic people, numerous works were written about religion, culture and history of Islam. Among them, it can be refer to translations of Quran, commentaries, the history of prophets, lives of religious elders, jurisprudential books and the like, which have been written to promote Islam, the correct teaching of religious laws and their implementation. In Turkic language, the works with such contents have been often translated from Persian or Arabic. The purpose of present study was to investigate the Chagatai translation of Keydani jurisprudence as one of the important juristic books of Hanafi School. The original work has been written in Arabic by Lutfullah Keydani (d. 1349). This book had been considered as one of the important sources of jurisprudence during that era and afterwards and was later translated into Persian and Turkic languages. The translations are known by many different names because they have been translated by different translators. One of the considered translations is Muʻallimu'l-Etrak. This book is kept in the National Library of Iran under number 34234. In present study, the book has been introduced and some of its general features as well as its linguistic features have been discussed.

Background: Cysticercosis in among the neglected tropical disease caused by eating the egg of parasite Taenia solium. In this review, we aimed to verify the prevalence of human cysticercosis in different countries of Asia using systematic review and meta-analysis approach. Methods: Based of the protocol, reliable databases including PubMed, SCOPUS, Science Direct, Embase, and Cochrane Library from 1990-2018 were searched using a panel of keywords. Overall, 48 countries of Asia were searched in turn and data were analyzed using a category of statistical tests. Results: Out of 28 included studies, 586175 samples were collected and included in the data analysis. Based on the meta-analysis results, the overall pooled percent of cysticercosis was estimated 3.8% (95% CI: [2.0, 7.0]). According to the result of heterogeneity statistics including I-squared, chi-square, and tau-squared, it was statistically significant (Tau2 = 2.94, chi2 = 12733.31, P

Formal education in Iran, especially higher education, has been a means to smoothen the road to social mobility, provide good jobs, and boost people’s earnings. Now, being a university graduate and remaining unemployed is regarded as a challenge. In addition, governments consider this new unemployment a threat to their legitimacy. It seems that young unemployed graduates experience different problems in their social lives. This study aims to investigate the problems encountered by young unemployed graduates and to identify which aspects of situation provide a threatening condition for the society and government. This study has adopted a qualitative approach to answer these questions. It has been conducted in a Kurdish-Iranian context. The authors used a sample of 22 unemployed graduates and conducted semi-structured interviews with each of the sample members. The data gathered from the interviews were analyzed using the qualitative content analysis method. There emerged several themes that described the unemployed graduates’ lives. Findings show that the definition of job is gender based. Unemployment is interpreted as “illness,” “uselessness,” and “social injustice.” To cope with the unemployment issue, the unemployed graduates have to follow different strategies, including “seclusion,” “continuing education,” or “restarting education.” They experience in such a context different psychological, interactive, and behavioral challenges that sometimes make them adopt an anti-social position. The findings of this research contribute to a clearer understanding of the pathological aspects of unemployed graduates’ lives, which is considered a threat from their own viewpoints.

Nowadays, in addition to technical efficiency, the demands for environmentally-friendly machining processes have increased. In this context, development of an efficient strategy for machining of ceramic matrix composites (CMCs) has found crucial importance. CMCs exhibit outstanding properties, especially under harsh and severe conditions. Machining of CMCs, however, suffers from several disadvantages such as substantial costs, high tool wear, poor surface quality and low material removal rate, highlighting the need for optimization and development of efficient machining strategies. Due to extreme hardness of the ceramic matrix, grinding with diamond abrasives is inevitable. The grinding variables and the coolant-lubricant medium play significant roles in reduction of the energy dissipation and improving the finishing quality. Among coolant-lubricant types, minimum quantity lubrication (MQL) technique, which is known as an inexpensive and environmentally-compatible grinding process, can give the best results. In comparison with dry grinding condition, 37.95% reduction in cutting force, 75.93% reduction in surface roughness, and 150% increase in grinding efficiency have been achieved by MQL method. Considering MQL as the optimum coolant-lubricant medium, four machining strategies were developed using desirability function method in which efficiency, quality, and productivity were studied. Moreover, microstructure analysis and also cutting mechanism of grinding process for different types of fiber orientation have been investigated.

The authors aim to present a model that examines the constructs affecting the quality of accounting education at the undergraduate level in the context of Iran. To reach a conclusion, they use grou...

Since the development of data centers, power management (i.e., assessment, consumption and monitoring) has been a great challenge among scientists and engineers. By emerging a new generation of data center in the form of Hyperscale cloud data centers (HCDC), this concern has become more devastating than ever. The huge physical scale and the high level of system utilization through large power compensating system are some of the main characteristics of today’s HCDC. The lack of appropriate power assessment from available power estimation models, prevents professionals from designing an accurate HCDCcapacity planning. In particular, during steady state workload processing at the high utilization rate of HCDCtechnology, the inlet cold temperature level rises up and this trace can be effect to the computable power consumption. In this article, we show how the ambient temperature have significant negative impact on power consumption and for an accurate and proper estimation of the power consumption of HCDC, we propose a temperature-aware power consumption model. The model is evaluated by SimWare for various server types and configurations and results prove the effectiveness and accuracy of the proposed model. At the end, we show the proposed model can be applicable for both homogeneous and heterogeneous HCDCs.

Background: Patients with type-2 diabetes have poor adherence to the therapeutic regime. It can result in various complications in body systems associated with undesirable metabolic control. Purpose: The present study aimed to explore the inhibitors of medication adherence in patients with type-2 diabetes. Patients and methods: This was a qualitative study using a conventional content analysis method. Participants were 12 patients with type-2 diabetes referred to the diabetes unit in Saghez, Kurdistan Province in 2015. The purposive sampling method was used with a maximum variation in sampling, and data collection was continued until data saturation was achieved. Semi-structured interviews were used for data collection. Interviews were recorded and immediately transcribed verbatim. Results: Data analysis led to the development of four main categories including disbelief in medical explanatory/prescriptive knowledge, lived experiences of the disease, challenges of everyday life, and interactive/economic challenges. The main inhibitors were the patient's understanding of his/her own physical status and strategies used for maintaining the internal balance. Healthcare providers need to take patients' perceptions into account when they are prescribing medicinal diets. Another inhibitor was the incidents of everyday life, including economic and social challenges, and interactions to receive education and skills for living with the disease. Conclusion: Beliefs of the medical team and patients should be brought closer to each other, and patients' trust in the medical team should be increased. Nurses should consider the unique experience of every patient when giving healthcare recommendations, and try to limit the existing challenges as much as possible.

Subsurface damage (SSD) is a predominant type of damage in grinding process of optical materials with direct effect on the optical components performances. A series of cup wheel grinding trials were carried out on optical glass BK7 under different grinding parameters to evaluate their impacts on SSD and surface roughness. The SSD depths of ground specimens were measured by the wedge chemo-mechanical polishing (W-CMP) method. The modified model of Lambropoulos, proposed by Li, was applied considering the ductile regime effect. Besides, a three-dimensional model was established based on the coupled finite element method (FEM) and smoothed particle hydrodynamics (SPH) to simulate the grinding-induced SSD in optical glass BK7. The experimental results were compared with the theoretical model and simulations which showed a good agreement. Therefore, both the theoretical and simulation models could be used for fast and nondestructive evaluation of SSD. Also, a novel method was applied to calculate the crack length of a SEM micrograph through image processing technique.

Background Assessment is a necessary part of training postgraduate medical residents. The implementation of methods located at the “shows how” level of Miller’s pyramid is believed to be more effective than previous conventional tools. In this study, we quantitatively compared electronic and conventional methods in assessing ophthalmology residents. Methods In this retrospective study, eight different conventional methods of assessment including residents’ attendance, logbook, scholarship and research skills, journal club, outpatient department participation, Multiple Choice Question (MCQ), Objective Structured Clinical Examination (OSCE), and professionalism/360-degree (as one complex) were used to assess 24 ophthalmology residents of all grades. Electronic media consisting of an online Patient Management Problem (e-PMP), and modified electronic OSCE (me-OSCE) tests performed 3 weeks later were also evaluated for each of the 24 residents. Quantitative analysis was then performed comparing the conventional and electronic assessment tools, statistically assessing the correlation between the two approaches. Results Twenty-four ophthalmology residents of different grades were included in this study. In the electronic assessment, average e-PMP scores (48.01 ± 12.40) were much lower than me-OSCE (65.34 ± 17.11). The total average electronic score was 56.67 ± 11.28, while the total average conventional score was 80.74 ± 5.99. Female and male residents’ average scores in the electronic and conventional method were (59.15 ± 12.32 versus 83.01 ± 4.95) and (55.19 ± 10.77 versus 79.38 ± 6.29), respectively. The correlation between modified electronic OSCE and all conventional methods was not statistically significant (P-value >0.05). Correlation between e-PMP and six conventional methods, consisting of professionalism/360-degree assessment tool, logbook, research skills, Multiple Choice Questions, Outpatient department participation, and Journal club active participation was statistically significant (P-value Conclusion In this study, we conclude that electronic PMP can be used alongside all conventional tools, and overall, e-assessment methods could replace currently used conventional methods. Combined electronic PMP and me-OSCE can be used as a replacement for currently used gold-standard assessment methods, including 360-degree assessment.

The main purpose of this pilot study was to assess the regional diagnostic reference level (RDRL) of computed tomography (CT) examinations to optimise medical exposure in five pediatric medical imaging centers in Tehran, Iran where the most frequent CT examinations were investigated. For each patient, CT volume dose indexes (CTDIvol) and dose length product (DLP) in each group were recorded and their third quartile was calculated and set as RDRL. Pediatrics were divided into four age groups (

BackgroundThe SARS-CoV-2 epidemic broke out in December 2019 and now is characterized as a pandemic. The effective control of this infectious disease requires access to diagnostic techniques, both for case finding and epidemic size estimation. The molecular technique is routinely being used worldwide. Although it is the “standard” case detection and management method, it has its own shortcomings. Thus, some easy-to-use rapid serological tests were developed.MethodsOne hundred and fourteen positive RT-PCR-diagnosed patients were tested by VivaDiag Kit, a brand of rapid serological kits available in hospitals affiliated to Tehran University of Medical Sciences (TUMS), Tehran, Iran. Frozen serum specimens taken from healthy people in summer and autumn 2019, were also tested as negative controls.ResultsThe test sensitivity was 47.9% (95% confidence interval [CI]: 38.8-56.9) for IgM and 47.0% (95% CI: 38.0-56.0) for IgG. There was no difference between IgG and IgM seropositivity except in one case. Specificity was calculated as 99.0% (95% CI: 96.4-99.9) for IgM and of 100.0% (95% CI: 0.98.2-100.0) for IgG. Sensitivity was higher in men and older participants.ConclusionThis test can be used for epidemiological investigations especially for the estimation of the level of infection in the community, after it is properly corrected for sensitivity and specificity. The low sensitivity could be attributed to the technical limitation of the kits or low levels of antibodies after infection. The different sensitivity in age and sex groups supports the hypothesis that different people show different immune responses to this virus.

Background: The Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epidemic broke out in December 2019 and is now characterized as a pandemic. Effective control of this infectious disease requires access to diagnostic techniques, for both case finding and epidemic size estimation. The molecular technique is routinely used worldwide. Although it is the "standard" case detection and management method, it has its own shortcomings. Thus, some easy-to-use rapid serological tests have been developed. Methods: One hundred and fourteen positive RT-PCR-diagnosed patients were tested by VivaDiag Kit, a brand of rapid serological kits available in hospitals affiliated to Tehran University of Medical Sciences (TUMS), Tehran, Iran. Frozen serum specimens taken from healthy people in summer and fall 2019 were also tested as negative controls. Results: Test sensitivity was 47.9% (95% confidence interval [CI]: 38.8-56.9) for IgM and 47.0% (95% CI: 38.0–56.0) for IgG. There was no difference between IgG and IgM seropositivity except in one case. Specificity was calculated as 99.0% (95% CI: 96.4–99.9) for IgM and of 100.0% (95% CI: 0.98.2–100.0) for IgG. Sensitivity was higher in men and older participants. Conclusion: This test can be used for epidemiological investigations, especially for the estimation of the level of infection in the community, after it is properly corrected for sensitivity and specificity. The low sensitivity could be attributed to the technical limitations of the kit or low levels of antibodies after infection. The different sensitivity in age and sex groups supports the hypothesis that different people show different immune responses to this virus.

This article is a Letter to the Editor and does not include an Abstract.

Background Repetitive transcranial magnetic stimulation (rTMS) is a potential non-invasive treatment for post-traumatic stress disorder (PTSD). However, the treatment parameters of rTMS required to optimize therapeutic efficacy remains unclear. Objective The aim of the present study was to investigate the efficacy of bilateral rTMS and unilateral right rTMS and compare the efficacy of bilateral rTMS and unilateral rTMS on PTSD symptoms. Methods Sixty-five veterans with current combat-related PTSD symptoms were randomly selected to receive bilateral rTMS (1200 pulses at 20 Hz followed by 1200 pulses per session), unilateral right rTMS (2400 pulses at 20 Hz) or sham rTMS over the dorsolateral prefrontal cortex (DLPFC). Results Results showed significant differences among the 3 groups. Patients demonstrated significant PTSD symptom reductions in the bilateral group compared to the sham group in session five and endpoint. There were no significant differences between the bilateral and unilateral right groups at endpoint. Unilateral right group when compared to sham group showed greater symptom reductions from baseline to endpoint. There were no significant differences between the unilateral right and sham groups in session five. Conclusion Our findings suggest that bilateral and unilateral right rTMS are superior to sham rTMS but does not support the hypothesis that bilateral rTMS is more effective than unilateral high-frequency right-sided rTMS.

Jale Ghaemmaghmi is the late Ghajar and first Pahlavi poet who has social-political thought and is the outstanding poet among female poets. However, she is anonymous as the consequence of her limitation in her life. By studying her poems, it is found that her social-political thought is in line with some famous thinkers such as Dehkhoda, Bahar and Kasravi. She has more social poems in comparison to Forugh Farokhzad. This paper aims at investigating her thought by categorizing her poems to introduce the hidden layers of her thought to contemporary researchers in literature and sociology.

Olive in its various ripening stages is an important agricultural product, especially for its oil. Early detection of ripening stages of on-branch olives provides an insight into suitable site-specific managements. To fulfill these requirements, a model has been developed in the current study. This model is based on RGB images and deep Convolutional Neural Networks (CNN). Two Iranian olive cultivars (Zard and Roghani) in four ripening stages (immature, green maturity, black maturity, and fully mature) were considered (total eight classes). No structured imaging system was considered to ensure a natural condition of the experiment and generality of the method. The proposed model was selected based upon testing several popular or developed CNNs, and according to the criterion such as accuracy, prediction time, and computational burden. Multiple layers of Convolution, Max-Pooling, and Batch Normalization, followed by a Global Average Pooling layer (GAP), were contained in the proposed model. For this network, six different optimizers, i.e., Adagrad, SGD, SGDM, RMSProp, Adam, and Nadam, were evaluated, among which Nadam showed the best efficiency. According to the results, the overall accuracy of the proposed model was 91.91 %, and it performed the processing of a single frame in only 12.64 ms on CPU. It reflects the real-time potential and the robustness of the model to classify on-branch olives based on their ripening stages. If an orchard consists of just Zard cultivar or both the Zard and Roghani cultivars, the unripe Zard cultivar, among all eight classes, will be recognized with 100 % accuracy. However, if the Roghani cultivar is only considered, the over-ripening stage will be recognized with the highest accuracy. The results of this study showed that the proposed model could be effectively embedded in a system to treat olive trees based on the conditions of a particular branch in precision horticulture.

The article's abstract is not available.

Background & Aim: Abortion, as one of the factors affecting maternal health, is considered as a health and social problem. This paper aimed to investigate the status of abortion among Kurdish women in Mahabad and to determine the prevalence of spontaneous abortion and induced abortion and its related factors. Materials & Methods: This research is a cross-sectional survey. The study sample size included 360 married women, aged 15- 49 years old. Researcher constructed questionnaire was adopted for collecting data. Using cluster sampling, four regions were selected, and women were chosen through random sampling. Data were analyzed by SPSS and PLS software, and X2 and Logistic regression (P= 0.05) were adopted for analyzing the relationships of variables. Results: A total of 30.6 % of women had experienced abortion and 34.5% of them had induced abortion. Women with high socioeconomic status mostly committed induced abortion and those with low-level socioeconomics had spontaneous abortion (x2 = 6.421, P = 0.02). Women who were employed or had high level of education mostly committed induced abortion (x2 = 28.40, P= 0.001). According to logistic regression, individualism (B = 0.612, P= 0.04), rationality (B = 0.979, P= 0.02), and adherence to religion (B =-0.987, P= 0.006) had significant impacts on committing induced abortion. Conclusion: Unmet needs of women can affect induced abortion. Unmet needs besides religious and secular beliefs may determine the level of induced abortion in society. The increasing tendency toward individualism and instrumental rationality may increase the couples’ tendency to control the number of children. It is the case while the failure of contraception may lead to induced abortion.

Coal combustion has attracted a lot of interest by generating combined heat and power (CHP) due to low costs and high efficiency. However, one of the most important challenges in coal combustion is the environmental issues related to the process. In this article, the influence of some critical parameters, i.e., oxygen ratio, system pressure, residence time, and coal particle size, on output temperature and greenhouse gas emissions was evaluated using a kinetic model and an experimental study. Results showed that an increase in oxygen ratio leads to a significant increase in output temperature. It is also found that the particle size plays a negligible role in the process; smaller particles favor the production of gas products and higher combustion efficiencies. Modeling data validated against experimental measurements and were found to be in a good agreement.

Currently, there is not definitive information regarding the efficacy of transcranial direct current stimulation (tDCS) for Post-traumatic stress disorder (PTSD). This study aimed to examine the efficacy of tDCS for PTSD and its sub-symptoms. In a double-blind, controlled randomized clinical trial, 40 participants with PTSD were randomly assigned to receive either 10 tDCS sessions delivered at 2 mA to the right (cathode) and left (anode) dorsolateral prefrontal cortex (DLPFC) or 10 sham tDCS sessions to the same area. A blinded rater assessed PTSD, depressive, and anxiety symptoms before treatment, following it, and after a 1-month follow-up period. According to the results: i) PTSD patients demonstrated a significant reduction in PTSD symptoms, hyper-arousal and negative alterations in cognition and mood sub-symptoms as well as depressive and anxiety symptoms in the active stimulation compared to the sham stimulation at post-treatment and follow-up; ii) active stimulation when compared to sham stimulation revealed greater reductions in re-experiencing sub-symptoms from baseline to post-test. However, follow-up differences did not reach significance; iii) With respect to avoidance sub-symptoms, there were no significant differences between the active and sham stimulation at post-test and follow-up. This study supported the efficacy of 10 sessions of bilateral DLPFC tCDS delivered at 2 mA for the treatment of PTSD symptoms. Taken together, these findings suggest that although tDCS can reduce PTSD symptoms, researchers should consider the different types of PTSD and use strategies to ensure sufficient power to detect a potential effect of tDCS on various types of PTSD.

OBJECTIVES: The study systematically reviewed the effectiveness of pharmacological treatments alone or combined with brief cognitive-behavioural therapy (BCBT) for treating Iranian amphetamine abusers. The secondary aim was to review the efficacy of BCBT alone or combined with pharmacological treatments for treating amphetamine abusers in the world. EVIDENCE ACQUISITION: Published trials were considered for inclusion. The review was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Web of Science, MEDLINE (via PubMed), Cochrane Central Register of Controlled Trials, Cochrane Drugs and Alcohol Group’s Specialised Register of Trials, Embase, CINAHL, Scopus, PsychINFO, Iran Medex, Magiran and the Scientific Information Database were searched (January 2001 to March 2019). The reference lists of included studies were hand searched for more information. A systematic literature search in eight databases produced 10 trials. RESULTS: Risperidone reduced positive psychotic symptoms while aripiprazole reduced negative psychotic symptoms. Methylphenidate reduced craving and depression compared with placebo. Topiramate reduced addiction severity and craving for methamphetamine abuse compared with placebo. Buprenorphine reduced methamphetamine craving more than methadone. Haloperidol and risperidone reduced psychosis. Riluzole reduced craving, withdrawal, and depression compared with placebo. Abstinence from amphetamine or reduction in amphetamine abuse was confirmed in four BCBT studies and one study which applied BCBT with a pharmacological treatment which were stable between two and 12-months. Other changes in BCBT studies were as follows: reduced polydrug use; drug injection, criminality and severity of amphetamine dependence at six-month follow-up; improved general functioning; mental health; stage of change as well as improved motivation to change in a pharmacological + BCBT study. CONCLUSION: A review of trials indicates that pharmacological treatments and BCBT in a research setting outperform control conditions in treating amphetamines abuse and associated harms. Large-scale studies should determine if both treatments can be effective in clinical settings.

The application of linear motor-driven stages as the feed drivers of CNC micro milling machine tools is growing. In addition to employ high speed and high precision equipment such as linear motor-driven stages, the precision of the machined contours is highly dependent on the capabilities of the servo controllers. In this paper, the design of a precise controller for a two-axis LMDS has been investigated for micro-milling applications. In such feed drives, disturbances such as friction, force ripples, and machining forces have adverse effects on the workpiece positioning precision due to the direct drive concept behind them. Therefore, in order to have an acceptable transient response and disturbance rejection properties, a two-degree-of-freedom proportional–integral–derivative controller was employed for each axis. To design this controller, the zero-placement method was used. To compensate disturbances and machining contour errors, the utilization of Kalman filter observers, neural networks, cross-coupled controllers, and different integration of them were studied. The controllers were experimentally examined for circular motions. An integrated controller consisted of a Kalman filter disturbance observer, a cross-coupled controller, and a well-designed two-degree-of-freedom proportional–integral–derivative controller resulted in a high contouring and tracking precision. The controller could also reduce the spikes caused by the friction at the motion reversal points such as the quadrants in circle trajectories.

Gasification is a thermochemical process which converts organic fuels into a high caloric value syngas and other chemicals in the presence of a gasification agent. Tar generation represents the strongest barrier for the use of fixed-bed reactors for liquid fuel gasification, whereas sufficing is only possible with catalytic activities and expensive physical processing. In this work, a kinetic model of waste oil gasification was proposed which can be used a flexible model to provide a quantitative prediction of product yield of other fuels. Results were validated against the experimental measurements and showed a good agreement. In accordance with the modeling results, it was found that the greenhouse gas emission (GGE) of waste oil is higher than that of biomass materials, but the caloric value of the syngas generated is higher. The residence time was also recognized as an important design parameter to improve the syngas volume fraction.

Piezoelectric cantilever actuators are widely used in micro/nano-positioning applications due to their relatively accurate response and large operating bandwidth. One of the main obstacles in the way of implementing high-accuracy position tracking in high frequencies is the piezoelectric hysteresis phenomenon. It is known from previous research that piezoelectric materials exhibit a rate-dependent hysteresis loop. The purpose of this article is to obtain a novel hysteresis model that can accurately describe the output of the piezoelectric actuator. This is done by introducing a hysteresis model in the form of an actuated linear dynamic system. This model provides the ability to capture both rate-dependence and magnitude characteristics of the system, and it is simple and easy to implement in real-time. As a result, the proposed method accurately predicts the position of the piezo-actuated beam in a wide range of input frequencies and amplitudes. To demonstrate its effectiveness, the proposed hysteresis model is used along with a robust control loop to track the position of a piezo-actuated beam plant. It is shown using experimental results that utilizing this model leads to accurate position control in a wide range of frequencies.

This research develops a multiple-surface sliding mode control (MSSC) approach for position control of a servo-pneumatic system in the presence of mismatched uncertainties due to the friction force of the cylinder sealing. Servo-pneumatic actuators have many applications such as industrial automation, haptic interfaces, rehabilitation robots and non-invasive surgeries. Non-linearities due to internal and external disturbances, such as the friction force between the piston seal and cylinder wall, make it difficult to achieve adequate performance from these actuators. Thus, modelling and identification of friction parameters is an essential part of the controller design procedure. A simple model for friction such as the Stribeck model may be used in order to reduce the complexity of the identification procedure. In addition, a bounded uncertainty owing to the unmodelled dynamics of friction is considered. The lack of direct measurement for systems velocity necessitates finding a solution to estimate this parameter. One answer to this problem is to employ a high-gain observer. Whereas mismatched uncertainties appear in the state space equation of the system before control input, control input cannot apply directly to them. In the proposed framework, an MSSC scheme has been used to cope with these types of uncertainties. Asymptotic stability of the closed-loop system is proven by using the Lyapunov method; experimental results show that the proposed controller can deliver a good tracking performance and is robust to uncertainties. Experimental results validate the controller performance.

Introduction: Bipolar patients have abnormalities in cognitive functions and emotional processing. Two resting state networks (RSNs), the default mode network (DMN) and the sensorimotor network (SMN), play a decisive role in these two functions. Dorsolateral prefrontal cortex (DLPFC) is one of the main areas in the central executive network (CEN), which is linked to the activities of each of the two networks. Studies have found DLPFC abnormalities in both hemispheres of patients with bipolar depression. We hypothesized that the bilateral repetitive transcranial magnetic stimulation (rTMS) of DLPFC would produce changes in the activity of both the SMN and DMN as well as relevant cognitive function in patients with bipolar depression that responded to treatment. Methods: 20 patients with bipolar depression underwent 10 sessions of 1 Hz rTMS on right DLPFC with subsequent 10 Hz rTMS on left DLPFC. Changes in electroencephalography resting networks between pre and post rTMS were evaluated utilizing low-resolution electromagnetic tomography (eLORETA). Depression symptom was assessed using the Beck Depression Inventory (BDI-II) and cognitive function was assessed by Verbal Fluency Test (VFT), Rey Auditory Verbal Learning Test (RAVLT), Stroop Test, and Wisconsin Card Sorting Test (WCST). Results: Responders to rTMS showed significantly lower DMN activity at baseline and a significant decrease in SMN connectivity after treatment. Non-responders did not significantly differ from the control group at the baseline and they showed higher activity in the SMN, visual network, and visual perception network compared to control group following treatment. Bilateral rTMS resulted in significant changes in the executive functions, verbal memory, and depression symptoms. No significant changes were observed in selective attention and verbal fluency. Conclusion: Bilateral stimulation of DLPFC, as the main node of CEN, results in changes in the activity of the SMN and consequently improves verbal memory and executive functions in patients with bipolar depression.

In this paper, a rate control algorithm for variable bit rate video applications with buffer constraint is proposed. The proposed algorithm utilizes a fuzzy rate controller and a perceptual quality controller. The fuzzy controller computes a base quantization parameter (QP) for each video picture to provide the buffer constraint. Then, the perceptual quality controller uses a human visual system (HVS) model namely foveated just-noticeable distortion (FJND) model to improve the perceptual quality of encoded video by modulating the QP of macroblocks around the picture QP. The proposed rate control algorithm has been implemented on the JM H.264/AVC reference software and obtained experimental results show that it can produce encoded videos with high perceptual quality while the buffering constraint is strongly obeyed.

The electro-hydraulic servo system (EHSS) demonstrates numerous advantages in size and performance compared to other actuation methods. Oftentimes, its utilization in industrial and machinery settings is limited by its inferior efficiency. In this paper, a nonlinear backstepping control algorithm with an energy-saving approach is proposed for position control in the EHSS. To achieve improved efficiency, two control valves including a proportional directional valve (PDV) and a proportional relief valve (PRV) are used to achieve the control objectives. To design the control algorithm, the state space model equations of the system are transformed to their normal form and the control law through the PDV is designed using a backstepping approach for position tracking. Then, another nonlinear set of laws is derived to achieve energy-saving through the PRV input. This control design method, based on the normal form representation, imposes internal dynamics on the closed-loop system. The stability of the internal dynamics is analyzed in special cases of operation. Experimental results verify that both tracking and energy-saving objectives are satisfied for the closed-loop system.

Digital video stabilization (DVS) allows acquiring video sequences without disturbing jerkiness, removing unwanted camera movements. A good DVS should remove the unwanted camera movements while maintains the intentional camera movements. In this article, we propose a novel real-time DVS algorithm with a short-delay. The proposed DVS compensates the camera jitters applying an adaptive fuzzy filter on the global motion of video frames. The adaptive filter is an infinite impulse response (IIR) non-causal filter which is tuned by a fuzzy system adaptively to the camera motion characteristics. The fuzzy system itself is also tuned during operation according to the amount of camera jitters. The fuzzy system uses two inputs which are quantitative representations of the unwanted and the intentional camera movements. The global motion of video frames is estimated based on the block motion vectors which resulted by video encoder during motion estimation operation. Experimental results indicate a good performance for the proposed algorithm.

Actuator force control in servo-hydraulic systems has numerous applications in machinery and industrial settings. The prevalent hydraulic configuration for force control utilizes a proportional directional control valve to properly route the supplied hydraulic fluid toward the chambers of the actuator. It is well known that this configuration imposes certain physical limitations on force-tracking performance. In this article, a different configuration is utilized to improve the hydraulic force control performance. This is done by replacing the proportional directional control valve with a proportional double-stage relief valve. It is shown that this new setting is superior in its achievable force-tracking performance. This comes at the cost of a more challenging control problem compared to the proportional directional control valve case, due to the presence of un-modeled dynamics and unknown parameters. A robust [Formula: see text] control approach has been followed as the main solution to address uncertainty problems. However, conservative robust design imposes its own limitations on force-tracking performance. To address this issue, a combination of additional switched-proportional–integral–derivative and Prandtl–Ishlinskii hysteresis compensation control loops is proposed. Conditions are derived under which the additional loops improve the performance of the robust [Formula: see text] controller. The effectiveness of the proposed configuration and control method is demonstrated by the experimental results.

Electro-hydraulic servo systems (EHSS) are used in many industrial applications for position and force control. Force control with a hydraulic actuator is challenging and requires complicated control algorithms used along with high crossover frequency electro-hydraulic valves, even for simple force control tasks. In this paper, a different hydraulic structure is proposed to improve the force tracking quality and increase efficiency in the EHSS. This comes at the cost of a new model with linearization and uncertainty challenges. To address these challenges, a robust H∞ control design approach is followed to control the proposed EHSS. Model linearization uncertainties are approximated by a polytope and a robust controller is designed to keep the system stable and satisfy the H∞ performance conditions within this polytope. Experimental results verify that the objectives of the paper are satisfied after using the proposed system.

Among the prevalent methods in linear bilateral teleoperation systems with communication channel time delays is to employ position and velocity signals in the control scheme. Utilizing force signals in such controllers significantly improves performance and reduces tracking error. However, measuring force signals in such cases, is one of the major difficulties. In this paper, a control scheme with human and environment force signals for linear bilateral teleoperation is proposed. In order to eliminate the measurement of forces in the control scheme, a force estimation approach based on disturbance observers is applied. The proposed approach guarantees asymptotic estimation of constant forces, and estimation error would only be bounded for time-varying external forces. To cope with the variations in human and environment force, sliding mode control is implemented. The stability and transparency condition in the teleoperation system with the designed control scheme is derived from the absolute stability concept. The intended control scheme guarantees the stability of the teleoperation system in the presence of time-varying human and environment forces. Experimental results indicate that the proposed control scheme improves position tracking in free motion and in contact with the environment. The force estimation approach also appropriately estimates human and environment forces.

The electro-hydraulic servo system (EHSS) demonstrates a relatively low level of efficiency compared to other available actuation methods. The objective of this paper is to increase this efficiency by introducing a variable supply pressure into the system and controlling this pressure during the task of position tracking. For this purpose, an EHSS structure with controllable supply pressure is proposed and its dynamic model is derived from the basic laws of physics. A switching control structure is then proposed to control both the supply pressure and the cylinder position at the same time, in a way that reduces the overall energy consumption of the system. The stability of the proposed switching control system is guaranteed by proof, and its performance is verified by experimental testing.

In micromanipulation applications, controlling the force exerted on the object is of great importance. In such cases, any uncontrolled forces may damage the object or cause system failure. However, the presence of disturbances such as impedance uncertainties and hysteresis can strongly degrade force control performance and even lead to instability. Therefore, accurate force control when internal and external disturbances occur is a significant challenge. Conventional control methods usually have a number of restrictive conditions especially on the disturbance bounds. To rectify those issues, a modified robust disturbance rejection-based force control approach is proposed in this paper. For this purpose, an appropriate disturbance observer is utilized to estimate the disturbance effect regardless of amplitude. Then a robust control method is employed to achieve the disturbance-free desired dynamic. A modification is also performed to rectify the need for acceleration measurement in the control design. Finally, the force control for an unknown environment in the presence of disturbances is accomplished. The efficiency of the proposed approach is evaluated through simulation studies and compared with the well-known PI method. The experimental results validate the force control performance for the micropositioning piezoelectric actuator.

Bimorph Piezoelectric Cantilevered (BPC) actuators have been of increasing interest in micro-manipulation processes during recent years. Due to properties such as transverse vibration, the performance and manoeuvrability have considerably improved, compared with conventional longitudinal piezoelectric actuators. Therefore, dynamic modelling of such actuators has been the centre of attraction. For this purpose, a target point on the actuator, e.g. the cantilever end tip, is usually considered as the actuator output. One degree of freedom lumped and continuous type dynamic models have been considered in prior research works. These types of modelling lead to two significant issues. First, the effect of higher vibrational modes in the actuator output is disregarded. Second, a minimum phase dynamic system is achievable for all target points regardless of position. In this paper, these two issues will be analytically and experimentally investigated. To this end, a linear continuous dynamic model for a general B...

Self-sensing actuation has been extensively used in vibration control of flexible structures over the last three decades. Positive position feedback controller has been commonly used in this field due to the robustness against spillover phenomena. Piezoelectric clamped capacitance is the most important parameter that affects the performance of this technique. In this study, the effect of capacitance change on performance and stability of a self-sensing system with positive position feedback controller is investigated. Based on this analysis, some modifications are suggested to increase the stability of the closed-loop system against capacitance change. An online Fourier transform–based capacitance measurement method is used, which guarantees good performance and stability of closed-loop system in the presence of capacitance change. Experimental results are also presented to show the effectiveness of this method in vibration control of cantilever beam.

Precise control of piezoelectric actuators used in micropositioning applications is strongly under the effect of internal and external disturbances. Undesired external forces, unmodelled dynamics, parameter uncertainties, time variation of parameters and hysteresis are some sources of disturbances. These effects not only degrade the performance efficiency, but also may lead to closed-loop instability. Several works have investigated the positioning accuracy for constant and slow time-varying disturbances. The main concern is controlling performance and also the presence of time-varying perturbations. Considering unknown source and magnitude of disturbances, the estimation of the existing disturbances would be inevitable. In this paper, a compound disturbance observer-based robust control is developed to achieve precise positioning in the presence of time-varying disturbances. In addition, a modified disturbance observer is proposed to remedy the effect of switching behaviour in the case of slow time variations. A modified Prandtl–Ishlinskii (PI) operator and its inverse are utilized for both identification and real-time compensation of the hysteresis effect. Experimental results depict that the proposed approach achieves precise micropositioning in the presence of estimated disturbances.

The study is concerned with normal-strength concrete corbels. 30 such corbels were studied by finite element modelling and the variables considered include ratios of primary and secondary reinforcement, type of applied loading, vertical or horizontal. Finite element modelling with a software package LUSAS was used to analyse four series of corbels namely PV series (primary reinforcement with vertical loading), SV series (secondary reinforcement with vertical loading), PH series (primary reinforcement with horizontal loading) and SH series (secondary reinforcement with horizontal loading). The results indicate that corbels with neither primary reinforcement nor secondary reinforcement fail suddenly. In the case of PV series and SV series, corbels increase in ratio of primary and secondary reinforcement generally resulted in enhancement of strength and ductility when subjected to only vertical loading. This increase is significant up to 0.4% in the case of primary reinforcement and 0.3% in the case of secondary reinforcements. No noticeable change in ultimate load or ductility was observed for corbels in PH series and SH series. First published online:24 Oct 2013

This paper presents the research work on a 1 Degree of Freedom (DOF) macro-micro teleoperation system which enables human operator to perform complex task in micro environment such as cell insertion with the capability of haptic feedback. To reach submicron resolution, a nano-motion piezo actuator was used as the slave robot and a servo DC motor was used as the master robot. Force sensors were implemented at both ends for haptic feedback and a microscope equipped with camera was employed for real-time visual feedback. The hysteresis nonlinearity of the piezo motor was modeled using LuGre friction model and compensated for. A Sliding Mode Based Impedance Controller (SMBIC) was designed at the slave side to ensure position tracking while an impedance force controller was designed at the master side to ascertain tracking of the force. Control parameters were chosen based on Llewellyn stability criteria such that the entire system stays stable against parameter uncertainties and constant time delay. The experimental results demonstrated capability of the proposed control frameworks in desirable tracking of the position and force signals while the entire system remained stable. The results of this study can be used for complex tasks in micron environment such as cell insertion.

Context Considering the high prevalence of psychological distresses among patients with chronic physical diseases, the question is why do some of these patients not experience any disorders and cope better with their disease? Objectives The current study aims at reviewing the researches on resilience in adult patients with chronic diseases. Data Source In the present systematic review, articles published in English on resilience from March 2000 to July 2015 were searched using the keywords: Resilience OR Resiliency AND Illness OR Disease OR Chronic Disease in databases such as Google Scholar, Science Direct, PubMed, PreQuest, Scopus, and PsycINFO. Study Selection The process of screening and the initial selection of articles were based on systematic reviews and meta-analyses (PRISMA) guidelines. The methodological quality of the articles was studied using a modified version of quality of life index form. Eventually, 17 qualified studies were selected for the review. Data Extraction The form used to extract information included the variables of the first author of the article, the publication year, the place of the study, the type of the study, sample size, the data collecting instruments, and the most important findings. Results The results included resilience outcomes, protective factors and resilience-related risk factors. Psychological distresses were the most common risk factors, and self-efficacy and adaptive coping constituted the most common resilience-related protective factors. The findings showed that the protective factors, by mediating risk factors, resulted in positive outcomes such as proper treatment adhesion, better quality of life, psychological well-being, and self-care behaviors. Conclusions Resilience is a balance between risk factors and protective factors, and it develops or disappears through changes in the protective and risk factors. Patients with high resilience tend to enhance their protective factors and manage their everyday life in spite of disease-related limitations.

Background: Play, particularly pretend play, has a cognitive basis and has been linked to the language and social ability. Objectives: The goal of this study was to examine face and content validity, inter-rater, intra-rater and test-retest reliability of the Persian translation of the child-initiated pretend play assessment Methods: Ten occupational therapists consented to be in the content validity study. Face validity was examined by five occupational therapy specialists. For reliability, 31 typically developing children aged 4 - 6 years were chosen from kindergartens of four regions of Tehran, Iran. Two weeks after the initial assessment the children were re-tested for test-retest reliability. Intra-rater and inter-rater reliability was scored from videos of the children’s play assessment. Results: To be culturally appropriate for Iran, some phrases were changed and the pigs were replaced by dogs. Content validity index (CVI) and content validity ratio (CVR) were acceptable for all items. The Intra-class correlation coefficient was ICC = 0.99 for intra-rater reliability and ICC = 0.98 for inter-rater reliability. For test-retest reliability, the intra-class correlation coefficient for symbolic and combined object substitution scores and all elaborate play scores ranged from ICC = 0.69 to - 0.99. For imitated actions, the majority of children scored 0 on both test and re-test. Conclusions: The Persian version of child initiated pretend play assessment has appropriate face and content validity. Inter-rater and intra-rater reliability were excellent. PEPA, combined and symbolic NOS showed good to excellent test-retest reliability. Test retest reliability for conventional NOS was moderate and NIA was not stable with more children imitating the examiner in the first test but not the re-test.

Hydraulic systems are widely used in different industries; especially where high-magnitude forces are exerted. Traditional elector-hydraulic systems use a proportional or servo valve to control the position of hydraulic actuators. Low energy efficiency and high cost of these control valves are two important problems in these systems. Digital Hydraulics is one of the most novel methods, proposed to address these issues. Low cost, better energy efficiency, contamination insensitivity and low leakage are major advantages of Digital Hydraulics which make them popular among researchers. In this paper a Digital Hydraulic circuit is proposed, that uses a fast-switching on/off valve instead of servo valves to control the position of a hydraulic actuator. For this purpose the flow running through the fast-switching valve is controlled, employing proper PWM duty cycle. The excess flow of pump is discharged to the tank directly instead of going through the relief valve when the control valve is off. Thus the wasted energy, caused by the relief valve, is reduced significantly. A robust H∞ controller is applied to guarantee position tracking in the presence of uncertainties. The effectiveness of this method is tested after conducting experiments on a hydraulic test rig and presenting the experimental results.

Servo-Pneumatic actuators introduce some advantages such as cleanliness, high specific power and actuating force with high performance, comparing to electrical and hydraulic actuators. Servo-Pneumatic actuators are employed in many applications such as non-invasive surgeries, and rehabilitation robotics. High friction in servo-pneumatic actuators, due to the cylinder tight sealing, results in low controllability and decreases the system trajectory tracking performance. Therefore, position control of these actuators is a challenging issue. This paper presents a new approach for modeling the friction force called Generalized Maxwell-Slip model. According to GMS model, friction is constituted of two stages, namely “presliding” and “sliding”. Presliding stage is referring to friction force as velocity crosses zero. Moreover, friction illustrates a hysteresis behavior commensurate to displacement; therefore friction could be defined as a function of displacement in the presliding stage. Conversely, friction force in sliding stage is more of a function of velocity. Acquiring a model for hysteresis behavior is a problematic issue, which is resolved by using Generalized Prandtl-Ishlinski model. Consequently, attaining an accurate model for friction could help us to compensate this highly nonlinear phenomenon more precisely. Eventually, to achieve desirable tracking performance, multiple surface sliding mode controller is employed. To verify the effectiveness of the proposed approach, an experimental setup is developed and the acquired results show great improvement in tracking performance.

Electro-hydraulic servo systems are used as actuators for positioning and force exertion in heavy-duty and relatively precise industrial applications. In addition, to achieve the best performance of the system, all of the components must work properly. These systems are often subjected to some problematic issues such as leakage, fluid property variation, and actuator seal damage. These problems are called “faults” which degrade the control performance. This paper presents a novel approach for fault detection in electro-hydraulic servo systems using pressure signals analysis. The leakage fault influences many aspects of the fluid pressure signals. The proposed method is based on pressure signals analysis in one of the cylinder chambers in response to periodic square inputs to a proportional valve. For this purpose, propounded features are extracted from supply pressure signals. These features are considered as height, width, and location of peaks. In the proposed scheme, a support vector machine classifier has been exploited to classify systems into multiple classes including faultless systems and systems with different levels of fault. Moreover, this method does not need the model of actuator or leakage. The performance of proposed fault detection scheme was verified through experimental results.