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211.
Although a large body of research has been dedicated to examining emotional intelligence (EI) and learning styles in relation to different factors in academic setting, the relationship between these two variables still necessitates more exploration and deeper study, especially in the Iranian context. To this end, 60 English for Academic Purposes (EAP) learners were recruited to fill out the Farsi version of Emotional Intelligence Scale (FEIS-41) and Paragon Learning Styles Inventory (PLSI). The results revealed that the participants achieved the highest score in Optimism/Mood Regulation sub-scale of the FEIS-41. With respect to the four dimensions of PLSI, Sensing, Feeling, Judging and Extrovert were the participants’ preferred learning styles, respectively. Besides, analysis of data illustrated that gender did not affect their EI and learning styles preferences. Furthermore, the significance of 9 out of 12 computed correlations between three sub-skills of FEIS-41 and four dimensions of PLSI indicated the existence of correlation between EI and learning styles preferences of Iranian EAP learners.  相似文献   
212.
The present study investigated English as a foreign language (EFL) teachers’ attributions of success and failure. It also set out to investigate whether these attributions vary by teachers’ age, teaching experience, gender and educational level. To do so, 200 EFL teachers were selected according to convenience sampling among EFL teachers teaching English in Language Institutes in Mashhad and Tehran, two cities in Iran. The participants completed the language teacher attribution scale measuring four attributions: teaching competency (TC), teacher effort (TE), student effort (SE) and institution supervision (IS). The present study yielded mixed results regarding English language teachers’ attributions of success and failure events. It was also found that these attributions vary by their age, teaching experience and educational level, but not by gender. The discussion and implications of the research are further presented with reference to the earlier findings.  相似文献   
213.
Circulating tumor cells (CTCs) separation technology has made positive impacts on cancer science in many aspects. The ability of detecting and separating CTCs can play a key role in early cancer detection and treatment. In recent years, there has been growing interest in using deformability-based CTC separation microfilters due to their simplicity and low cost. Most of the previous studies in this area are mainly based on experimental work. Although experimental research provides useful insights in designing CTC separation devices, there is still a lack of design guidelines based on fundamental understandings of the cell separation process in the filters. While experimental efforts face challenges, especially microfabrication difficulties, we adopt numerical simulation here to study conical-shaped microfilters using deformability difference between CTCs and blood cells for the separation process. We use the liquid drop model for modeling a CTC passing through such microfilters. The accuracy of the model in predicting the pressure signature of the system is validated by comparing it with previous experiments. Pressure-deformability analysis of the cell going through the channel is then carried out in detail in order to better understand how a CTC behaves throughout the filtration process. Different system design criteria such as system throughput and unclogging of the system are discussed. Specifically, pressure behavior under different system throughput is analyzed. Regarding the unclogging issue, we define pressure ratio as a key parameter representing the ability to overcome clogging in such CTC separation devices and investigate the effect of conical angle on the optimum pressure ratio. Finally, the effect of unclogging applied pressure on the system performance is examined. Our study provides detailed understandings of the cell separation process and its characteristics, which can be used for developing more efficient CTC separation devices.  相似文献   
214.
215.
In this paper, a new technique is introduced for chaos secure data communication. In this approach, in addition to the usually used techniques for data encryption, the concept of carrier encryption is introduced to increase the security level of the secure communication scheme. To fulfill this objective, at the transmitting end, two chaotic oscillators are coupled, and a set of inequality time dependent constraints with time dependent bounds is imposed on the generated chaotic signals. Moreover, to increase system complexity and its security level, the imposed set of constraints and their bounds are allowed to be changeable from one time period to another during the transmission process. As a result, the patterns of the generated chaotic signals are completely changed and the chaotic oscillator is completely encrypted. At the receiving end, the newly developed Constrained Smoothed Regularized Least Square (CSRLS) observer is used to synchronize the received constrained chaotic signals and hence retrieve the transmitted data. Using such an approach, the quality of the received information, measured by the Bit Error Rate (BER), is highly improved due to the superior performance of the developed CSRLS observer. The stability of the observer is analyzed, and simulation results are presented to show the efficiency and effectiveness of the proposed secure communication scheme.  相似文献   
216.
In this study, an adaptive interval type-2 Takagi-Sugeno-Kang fuzzy logic controller based on reinforcement learning (AIT2-TSK-FLC-RL) is proposed. The proposed controller consists of an actor, a critic and a reward signal. The actor is represented by the IT2-TSK-FLC in which the antecedents and the consequents are interval type-2 fuzzy sets (IT2FSs) and type-1 fuzzy sets (T1FSs), respectively, which are named A2-C1. The critic is represented by a neural network, which approximates the optimal guaranteed cost in the control design to ensure the system stability for all admissible uncertainties and noise. The use of a reward signal to formalize the idea of a goal is one of the most distinctive features of RL. Thus, the proposed controller evolves in time as a result of the online learning algorithm. The parameters of the proposed controller are learned online based on the Lyapunov theorem to guarantee the stability, overcome the shortcomings of the gradient descent, such as the local minima and instability, and determine the learning rate of the IT2-TSK-FLC controller. Furthermore, the critic stability is discussed for determining the optimal learning rate. The proposed controller is applied to uncertain nonlinear systems to show its robustness in reducing the effect of system uncertainties and external disturbances and is compared to other controllers.  相似文献   
217.
This paper concerns the simultaneous fault detection and control (SFDC) problem for a class of nonlinear stochastic switched systems with time-varying state delay and parameter uncertainties. The switching signal of detector/controller unit (DCU) is assumed to be with switching delay, which results in the asynchronous switching between the subsystems and DCU. By constructing a switching strategy depending on the state and switching delays, new sufficient conditions expressed by a set of linear matrix inequalities (LMIs) is derived to design DCU gains. This problem is formulated as an H optimization problem and both mean square exponential stability and fault detection of augmented system are considered. A numerical example is finally exploited to verify the effectiveness and potential of the achieved scheme.  相似文献   
218.
Polycystic ovarian syndrome is one of the most common hormonally leading cause infertility disorders. The effect of oxidant-antioxidant imbalance on disease progression has been studied in many disorders. The present study was aimed to evaluate prooxidant–antioxidant balance (PAB) in patients with polycystic ovarian syndrome compared to healthy subjects. We also studied the possible effect of treatment with available drugs on serum PAB. In this case–control study 100 polycystic ovary syndrome (PCOS) patients and 100 healthy individuals were enrolled in the study. The laboratory features of patients and controls like as serum LH and FSH concentration and hematological examinations were collected. PAB was evaluated by a colorimetric method. Serum PAB value was significantly higher before treatment compared to after treatment and healthy subjects. PAB values were also higher in subjects with irregular menstrual cycle compared to normal subjects. Our results represented that serum PAB values has an indirect significant correlation with serum LH concentration. We also found that drugs regimen containing spironolactone effectively reduced the serum PAB values. Our results showed that PCOS patients had increased level of PAB and treatment with spironolactone mainly decreases the level of serum PAB. Our results indicate that the measurements of PAB may be used as a potential laboratory marker for assessment of PCOS patients.  相似文献   
219.
One of the most important complications of diabetes is nephropathy. This study investigates the effects of aqueous garlic extract on inflammation and oxidative stress status in the kidneys of diabetic rats. Male rats were divided into four groups- control rats, diabetic rats, garlic extract-treated diabetic rats, garlic extract-treated normal rats. The glucose, urea, uric acid, and creatinine levels were measured in sera using colorimetric methods. To determine the oxidative stress condition in the kidney tissues, total antioxidant capacity (TAC), malondialdehyde (MDA), and total oxidant status (TOS) were measured using colorimetric methods. Inflammation status was evaluated by the determination of tumor necrosis factor-alpha (TNF-α) gene and protein expression using qRT-PCR and ELISA respectively, while nitric oxide (NO) level in these tissues was measured using the Griess method. Histological examination of Kidneys was carried out by H&E staining. The levels of glucose, urea, and uric acid were found to increase in the serum of diabetic rats and decrease in that of diabetic rats after treatment with garlic. Measurement of MDA, TOS, and TAC revealed oxidative stress in diabetic rats, which improved after receiving the extract. The NO and TNF-α protein levels in diabetic rats were higher than those in control rats. After treatment with garlic, the levels of TNF-α protein and NO became close to the normal levels. Histological results confirmed certain other data as well. Garlic has antioxidant properties; therefore, it can reduce oxidative stress, which plays an important role in the development of diabetic nephropathy. Reduction in oxidative stress has beneficial effects on inflammation because it leads to a decrease in the level of TNF-α.  相似文献   
220.
In collaborative content generation (CCG), such as publishing scientific articles, a group of contributors collaboratively generates artifacts available through a venue. The main concern in such systems is the quality. A remarkable range of research considers quality metrics partially when dealing with the quality of artifacts, contributors, and venues. However, such approaches have several drawbacks. One of the most notable ones is that they are not comprehensive in terms of the metrics to evaluate all entities, including artifacts, contributors, and venues. Also, they are vulnerable to potential attacks.In this paper, we propose a novel iterative definition in which the quality of artifacts, collaborators, and venues are defined interconnectedly. In our framework, the quality of an artifact is defined based on the quality of its contributors, venue, references, and citations. The quality of a contributor is defined based on the quality of his artifacts, collaborators, and the venues. Quality of a venue is defined based on both quality of artifacts and contributors. We propose a data model, formulations, and an algorithm for the proposed approach. We also compare the robustness of our approach against malicious manipulations with two well-known related approaches. The comparison results show the superiority of our method over other related approaches.  相似文献   
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