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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of Artificial Intelligence in Electrical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Nonlinear Control,fault and failure,control actuators
- چکیده:
- چکیده انگلیسی: Control actuators' faults are among the major reasons to lose aircraft control while flights. The plane dynamics is severely dependent upon faults and errors in flight control systems and if the reformed control order is not issued by the fault tolerant controller there would be unpleasant outcomes such as inconsistency and the reduction of system performance and some dreadful aerial accidents will occur. This research includes the presentation of a fault tolerant control technique based on nonlinear optimal control method using Rekaty equation related to the state. The characteristics of nonlinear optimal control method entail the possibility of novel aircraft modeling and restructuring of the control systems when a fault occurs and this increases the possibility of flight save. The two scenarios of error and failure include the reduction of elevator efficiency and the exclusion of aileron of a great business aircraft from being controlled and the optimal function of nonlinear method compared with linear optimal control. It is the first time that this technique is used in local research projects as a control method. The results of simulations proved the effectiveness of the proposed approach in consistency retrieval and the preservation of flight route. Several linear and nonlinear controllers have been planned and implemented to control the position and status of flights. During some recent decades and due to lack of ability in linear control systems, there has been extending developments in methods such as linearization with feedback, interest tabling, return to past method, slide mode control, adjustment control, Thus, the goal of the present research is to design a nonlinear controller with a resistant approach for the systems. Also the simulation results showed efficiency of the controllers in flight consistency and system direction. The goal of the present study is to know different aircrafts especially Boeing 100-747, to study about the actuators' failures and to investigate about different types of aerial disasters and their reasons, to know different controlling and comparing techniques with nonlinear control technique and to design active controllers using nonlinear techniques for a Boeing 747 flight aircraft.
- انتشار مقاله: 24-09-1397
- نویسندگان: Alireza Sadraei,Alireza Ghafari Kashani
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Artificial Intelligence in Electrical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Trajectory tracking,Robust Control,Quadrotor Helicopter,SMC
- چکیده:
- چکیده انگلیسی: In this paper, a robust tracking control method for automatic take-off and trajectory tracking of a quadrotor helicopter is presented. The designed controller includes two parts: a position controller and an attitude controller. The attitude controller is designed by using the sliding mode control (SMC) method to track the desired pitch and roll angles, which are the output of position controller. The position controller is also a design using SMC and the attitude controller is faster than position controller.
- انتشار مقاله: 03-12-1394
- نویسندگان: Kamal Torabi,Alireza Ghafari Kashani
- مشاهده
- جایگاه : پژوهشی
- مجله: Asia Pacific Journal of Medical Toxicology
- نوع مقاله: Journal Article
- کلمات کلیدی: Iran,Amphetamines,High Pressure Liquid Chromatography,N-Methyl-3,4-methylenedioxyamphetamine,Street Drugs
- چکیده:
- چکیده انگلیسی: Background:Ecstasy, mainly composed of 3,4-methylenedioxymethamphetamine (MDMA), is one of the most popular addictive synthetic drugs. This study was aimed to investigate the amount of MDMA in the ecstasy tablets seized in West Azerbaijan province, northwest Iran and also to assess the relationship between the physicochemical and morphological characteristics of the tablets.
Methods: MDMA content of ecstasy tablets was analyzed using high-performance liquid chromatography method. Flow rate was 3 mL/min and mobile phase consisted of a mixture of acetonitrile and water containing triethylamine (pH = 3.2). The fluorescence spectrophotometer detector set at an excitation and emission wavelength of 220 and 306 nm, respectively. The retention time of ecstasy on this system was 2.2 minutes. The calibration curve was linear (R2= 0.999) over the concentrations ranging from 0.2 to 2 µg/ml. The limit of detection and the limit of quantitation were found to be 0.06 µg/L and 0.19 µg/L, respectively with six times repetition.
Results: In this study, 85 ecstasy tablets were analyzed. Mean weight of the tablets was 275.6 ± 70.4 (range: 158.5-403.3) mg. Mean MDMA content of the tablets was 30.53 ± 23.23 (range: 0.05-70.7) mg. The tablets were classified into 8 groups based on their morphological features (color and logo). Considering the tablet groups, physicochemical features of the tablets (weight, MDMA content, and MDMA to weight ratio) were significantly different (P < 0.001). Correlation analysis showed that the MDMA content and weight of tablets were significantly correlated (P = 0.04).
Conclusion: There is variability in the physicochemical properties of ecstasy tablets available in the black market for illicit drugs in northwest Iran. This variability may potentially put abusers at increased risk of overdose due to inadvertent excess ingestion of the tablets to achieve desired effects and also experiencing more harm due to tablets adulterants.- انتشار مقاله: 10-03-1393
- نویسندگان: Reza Ghafari,Amir Heydari,Mohammad Reza Vardast,Azam Akbari
- مشاهده