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Identification of the “aircraft dynamic modes” is one of the researchers’ favorite subjects in the flight mechanics field to study the behavior of airplane in maneuvers and nonlinear regime. Technically, by measuring the flight test parameters, the flight dynamic modes could be estimated. Although several approaches calculate precisely the linear flight dynamic modes, there is not a known standard procedure to calculate the nonlinear flight dynamic modes. In this paper, identification of the flight dynamic modes in highly nonlinear maneuver conditions and particularly in the coupled dynamic spin maneuvers is investigated. A new approach based on Hilbert–Huang Transform (HTT) for identification of the flight dynamic modes is presented in this paper. To overcome the mode mixing problem during decomposition which leads to imprecise results in the estimation of the flight dynamic modes, a Modified Ensemble Empirical Mode Decomposition (MEEMD) algorithm for processing of the complex signals that originate from FDR is presented in this research. This new algorithm is able to make a precise reconstruction of the original signal and it performs the task of signal decomposition with fewer iterations and so with less complexity order rather than the competitor approaches. An innovative algorithm for calculating flight dynamic modes natural frequencies and the damping ratios which uses the IMFs produced by MEEMD is presented. The obtained approach was applied to flight data, which belong to spin maneuvers. The results show the correct performance of the presented technique in the nonlinear flight regime.

Diazinon (DZ), an organophosphorus pesticide, has a large consumption for agricultural activities, which its discharge into groundwater and surface is associated with serious concerns for the animal and plants. Thus, the degradation of the mentioned pesticide from an aqueous environment was examined in the electro-Fenton (EF) and sono-electro-Fenton process (SEF) process using SS316/β-PbO2anode. To characterize the synthesized anode, the analyses, e.g., XRD, SEM, and EDX, were used. The central composite design (CCD) was the method used to assess the effect of selected parameters (DZ concentration = 25–75 mg/L, voltage = 5–15 V, pH = 3–9, and electrolysis time = 20–80 min) and their interactions on the DZ degradation in the evaluated system. Detecting the intermediates of DZ degradation was carried out by LC–MS analysis, and its degradation pathways were proposed. To conduct the toxicity tests for inlet and outlet, the growth inhibition percentage of Pseudomonas aeruginosaand Staphylococcus aureuswas estimated. SEF process could represent the DZ degradation, COD, and TOC removal efficiencies of 92.2%, 73.2%, and 67.4%, respectively. According to kinetic studies, the pseudo-first-order kinetic (R2> 0.99) was detected to be an adequate model for the enlightenment of data of the degradation of DZ by the evaluated system. Finally, DZ is converted into carbon dioxide (CO2( and water (H2O). The results of this study showed that the degradation and mineralization of DZ using the SEF process were successfully carried out.

In this paper, control of the nonlinear dynamics of quadrotor with the help of FOPID controllers was focused, moreover, this literature used neural networks method is used for tuning of the controller. In the next section, finding the optimal path which satisfies the constraints of speed and guarantees the safety and feasibility of the trajectory has been studied. For path planning, machine learning algorithm based on neural networks is used to emulate the controlled plant to raise the computational efficiency. For optimizing the path particle swarm optimization algorithm is considered. The results show the accurate and appropriate performance of the mentioned algorithm.

Dyes are one of the major environmental pollutants in the textile industry effluent. The Most of these compounds are toxic, carcinogenic, mutagenic, and biodegradable. In this study, the response surface method was used to determine the removal optimal conditions of acid blue 113 (AB 113) dye in the presence of nanoscale zero-valent iron (nZVI) particles as activators for persulfate (PS) and the mineralization rate of the dye were investigated. The structure and morphology of nZVI nanoparticles were investigated by using FTIR, FESEM, and XRD techniques. The experiments were evaluated based on the Box-Behnken design with five input parameters such as reaction time, pH, catalyst value (nZVI), PS value, and initial concentration of dye at three levels. Finally, the mineralization rate and kinetic studies were investigated to evaluate the oxidation process. The results of physicochemical analysis confirmed the accuracy of nZVI nanoparticle structure. Under optimal conditions, initial concentration of dye was 46 mg/L, pH = 3, reaction time was 50 min, catalyst dose = 0.08 g/L, PS = 0.14 g/L, and the removal rate obtained was 100%. The proposed model (quadratic) was confirmed by high correlation coefficient R2Adj= (0.9724) and R2= (0.9872). The results illustrated that the reaction kinetic conforms to the pseudo-first-order model (0.9985). The present study showed that the radicals obtained from the activation of persulfate using nZVI nanoparticles have a high efficiency in the removal of AB 113 dye. The results indicated that under optimal conditions, the efficiency of TOC for oxidation of acid AB 113 dye was 79.37%.

In this experimental study, alum adsorbent was synthesized using an electrochemical process consisting of aluminum (anode) and iron (cathode) electrodes in a 1 L cylindrical reactor. The structure of the alum adsorbent was investigated using transmission electron microscopy, scanning electron microscopy, X-ray diffraction, and Brunauer–Emmett–Teller techniques. Adsorption process experiments were evaluated with four input parameters such as pH (4–9), alum nanoparticles dosage (0.01–0.05 g/L), initial concentration of tannic acid (10–80 mg/L), and contact time (5–50 min). The isotherm and adsorption kinetics were examined under optimal experimental conditions to evaluate the adsorption process. The results of the physicochemical analysis confirmed the accuracy of the alum structure. Under optimal conditions of the adsorption process, pH, adsorbent dose, initial concentration of tannic acid, and contact time were 6, 0.05 g/L, 20 mg/L, and 50 min; Under these conditions, the removal efficiency of tannic acid was obtained to be 93.9%. The results of the adsorption isotherm and kinetics studies showed that the adsorption process follows the Langmuir isotherm (R2= 0.99) while the process kinetics corresponds to the second-order kinetics model (R2= 1). The results showed that alum can be used as a high-availability and cost-effective adsorbent to remove tannic acid from aqueous solutions.

This study has been carried out with the aim of evaluating the treatability of polycyclic aromatic hydrocarbon compounds of PAHs available in urban and industrial sewage sludge utilizing advanced chemical oxidation methods contingent on free sulfate radicals using hydrogen peroxide and heat activation methods. For this purpose, various parameters including (3, 5, 7, 9, and 10), persulfate’s concentration (2, 10, 5, 15, and 20 mmol), the ratio of peroxide to persulfate (1, 0.5, 0.3, 0.2, and 0.1), sludge temperature (25°C, 35°C, 45°C, and 55°C) and the primary concentration of PAHs were considered at the 20 d reaction periods. Through making use of gas chromatography– mass spectrometry (GC-MS), after 40-min period, the quality and quantity of the compounds available in the samples were determined using a mass detector and the drawn standards curve. After examining the effectiveness of eliminating PAH compounds in various conditions, the chemical oxygen demand test was carried out for the samples related to optimal removal of PAH compounds to determine the real efficiency of the process in eliminating intermediate compounds originated from PAHs oxidation. The results demonstrate that the advanced chemical oxidation method (persulfate-peroxide) can effectively result in the elimination of PAH compounds from the sludge.

Herein, two different extraction methods (Soxhlet and ultrasound assisted extraction) along with dispersive liquid-liquid microextraction (as an assisted clean-up and preconcentration technique) were applied for the measurement of selected polycyclic aromatic hydrocarbons (PAHs) in sewage sludge. The measurements were made using gas chromatography-mass spectrometry (GC-MS). The extraction efficiencies of the above-mentioned methods were investigated and subsequently compared. Briefly, high amounts of sludge were gently heat-dried and sieved and the resulting solids (5 g for the Soxhlet extraction and ultrasound assisted extraction each) were then subjected to the corresponding extraction method. To clean-up, after completion of the extraction phase, the extract was dried under a gentle stream of nitrogen and then diluted with acetone (1.5 ml) and finally passed through a PTFE syringe filter. Further on, tetrachloroethylene (C2Cl4, 12 μl) was added to the acetone solution and the resulting mixture was rapidly added to a vessel containing deionized water (5.0 ml) for assisting the clean-up process and further preconcentration. Afterwards, the sedimented organic phase (5 ± 0.5 μl) was withdrawn and injected into the GC/MS (1.0 μl) for identification and quantification of the PAHs. Some differences between the two methods were observed for reproducibility and limits of quantification and were determined to be insignificant and significant, respectively. Overall, Soxhlet extraction had better extraction efficiency compared to that of the Ultrasound assisted extraction for the PAHs.

Carbon Nanotubes (CNTs) in the fabrication of Glass Fiber-Reinforced Polymers (GFRPs) are applied through Electrophoretic Deposition (EPD) technique to improve their interlaminar shear strength and high velocity impact response. EPD is utilized to insert CNTs on the surface of Glass fibers (GFs), performing as fuzzy fibers in the GFRP’s interphase. This achievement improved the load transfer capacity of composite, especially in out-of-plane and high-rate loadings. So, high velocity impact experiments with blunt and ogival projectiles are applied to investigate the CNTs position on the impact response of GFRPs. Experimental studies revealed the supremacy of EPD to improve the mechanical performance of specimen regarding simple GFRP and also conventional specimen in which CNTs just mixed in the entire matrix. The interlaminar shear strength of GFRPs is enhanced by 42% in EPD specimens. Using various lay-ups in fabrication shows that CNT deposited layers in the core of simple layers demonstrated highest deflection before failure in short beam test. EPD of CNTs improved the ballistic limit and impact energy absorption of specimens by 45% & 20% regarding simple control GFRPs and 35% & 16% regarding conventional specimen, respectively.

One of the most important aspects of interceptive orthodontic diagnosis and treatment planning is space analysis. To date all methods use the size of permanent teeth to predict the dimensions of unerupted teeth. The aim of this study was to predict the permanent teeth size using maxillary primary first molar. The size of primary maxillary first molars and permanent canines and premolars of 80 subjects was measured on their dental casts. Regression equations were determined between the size of primary maxillary first molars and permanent canines and premolars. The new regression equations for predicting permanent tooth size in the maxilla and mandible were, respectively, $$ Y = 2.2X + 13 $$ Y=2.2X+13 and $$ Y = 2.4X + 9.5 $$ Y=2.4X+9.5 among females and $$ Y = 2.7X + 5.5 $$ Y=2.7X+5.5 and $$ Y = 2.4X + 9.5 $$ Y=2.4X+9.5 among males. The results show that the primary maxillary first molar size can be used to predict the size of unerupted permanent teeth.

ABSTRACTAmendment of empty fruit bunch (EFB) and vermicompost (VC) in coconut coir dust (CD) has been promoted as a potential alternate media in soilless culture. However, in commercial overview, several problems can be seen in the use of amendment with coconut coir dust as a growth media. The aim of this study was to investigate the effect of EFB and VC as organic amendment (10%–40%; v/v) on the growth and yield of tomato plant in CD media. Six treatments were used with five replications. A 100% CD with nutrient solution (electrical conductivity [EC] = 2.5 mS·cm−1) was used as control treatment. The other treatments were 30 EFB, 10, 20, 30, and 40% VC, which were equivalent to half strength of the nutrients supplied in control. The results showed that plants grown in CD with 20% VC had higher vegetative growth and yield.

The heritability of tolerance of wheat F$\_3$ lines to competition from annual ryegrass ( Lolium rigidum), and its relationship to morphological traits, were determined using crosses between wheat cultivars with good and poor competitive ability. Forty F$\_2$-derived F$\_3$ lines from a cross between two late flowering varieties (Machete × Spear) and 40 from a cross between early flowering varieties (Wilgoyne × Gutha) were grown in the field with and without annual ryegrass. There was significant genetic variation between lines within each of the two populations in a number of aspects of plant growth and development, including yield in monoculture. The estimates of heritability for % yield loss due to competition were 0.25 and 0.57 in the two crosses respectively, indicating that selection for high tolerance to competition in the F$\_3$ generation or later should be effective. Fairly strong relationships between height and % yield loss and between leaf length and % yield loss suggest that these may be useful auxiliary traits when selecting for low % yield loss. However, differences between crosses in the magnitude and sign of genetic and phenotypic correlation between traits indicate that competitive ability is a complex character influenced by many factors.

The rapid development of herbicide resistance in weeds, and environmental imperatives, have forced the consideration of non-chemical tactics such as crop competition for weed management. This review of wheat–weed competition examines the plant traits associated with wheat competitiveness, and the opportunities for plant breeding or manipulating crop agronomy to differentially favour the growth of the crop. Many studies have proven that enhancing crop competitive ability can reduce weed seed production and crop yield loss, although a number of difficulties in conducting this research are identified and suggestions are made for improvement. It remains to be seen whether crop competitiveness will be considered as a priority by farmers and plant breeders. Farmers require precise information on the reliability of agronomic factors such as increased crop seeding rate or choice of variety for enhancing crop competitive ability in different environments. Plant breeders need to know which plant traits to incorporate in varieties to increase competitive ability. A thorough analysis of the benefits and costs of enhancing wheat competitiveness is needed. Competitive wheat crops should be available as part of reliable and economical integrated weed management packages for farmers. herbicide resistance, plant traits, crop morphology, variety, competitive ability, interference, seeding rates, weed suppression, yield loss, crop tolerance, biotechnology.

The use of chemical pesticides in agriculture to increase the quantity and quality of crops ultimately leads to pollution of water and soil resources. The evaluation of parameters that can affect the efficiency of three-dimensional sono-electro-Fenton (3D/SEF) with PAC/Fe3O4particle electrodes using and SS316/β-PbO2anode in 2,4-D degradation, and those parameters were optimized by Taguchi design technique. Different analyses (i.e., Field emission scanning electron microscopy (FESEM), X-ray diffraction analysis (XRD), energy-dispersive X-ray spectroscopy mapping (EDX-mapping), vibrating sample magnetometer (VSM), and Fourier Transform Infrared Spectroscopy (FTIR) could approve the fruitful synthesis of PAC/Fe3O4and SS316/β-PbO2anode. By employing LC-MS analysis, the intermediates generated from pollutant degradation were spotted, and degradation pathways was proposed. The pH of the solution (with percentage contribution of up to 39.52%) was as the most effective independent variable on system response. The optimal conditions for removal of 2,4-D were determined to be as follows: 2,4-D concentration = 50 mβL, pH = 3; FeSO4= 0.08 mg/250 mL, electrolysis time = 60 min, H2O2concentration = 0.2 mL/L, current density = 5 mA/cm2, catalyst dose = 5 g/L, and Na2SO4concentration = 0.3 g/250 mL; in these conditions, removal efficiencies of the 2,4-D, COD and TOC were 96.2%, 92.31% and 86.5%, respectively. Moreover, significant reduction was detected in the biological toxicity of the outlet effluent from the 3D/SEF process. Finally, 2,4-D herbicide was completely degraded using hydroxyl radicals produced by the electrocatalytic process and converted into CO2and H2O products. Considering obtained results, the wastewater containing pesticides such as 2,4-D herbicide can effectively treated by 3D/SEF process, and it could offer acceptable results.

Charged spin-fields are coupled to an extended gauge model without the total suppression of the vector degrees of freedom which usually takes place as a consequence of simultaneously imposing the Maxwell and Rarita-Schwinger symmetries.

This paper presents the salient features of the Energy Management System which is being developed for Pacific Gas and Electric Company by Control Data Corporation. This project consists of two phases: Phase I contains the basic SCADA/AGC, scheduling applications, and the suppliers standard Real-Time Sequence of Network Applications. Phase II contains the addition of customized Network Applications and Dispatcher Training Simulator software. Phases I and II are scheduled to be delivered in 1989.

Identification of aircraft flight dynamic modes has been implemented by adopting highly nonlinear flight test data. This paper presents a new algorithm for identification of the flight dynamic modes based on Hilbert–Huang transform (HHT) due to its superior potential capabilities in nonlinear and nonstationary signal analysis. Empirical mode decomposition and ensemble empirical mode decomposition (EEMD) are the two common methods that apply the HHT transform for decomposition of the complex signals into instantaneous mode frequencies; however, experimentally, the EMD faces the problem of “mode mixing,” and EEMD faces with the signal precise reconstruction, which leads to imprecise results in the estimation of flight dynamic modes. In order to overcome (handle) this deficiency, an improved EEMD (IEEMD) algorithm for processing of the complex signals that originate from flight data record was introduced. This algorithm disturbing the original signal using white Gaussian noise, IEEMD, is capable of making a precise reconstruction of the original signal. The second improvement is that IEEMD performs signal decomposition with fewer number of iterations and less complexity order rather than EEMD. This algorithm has been applied to aircraft spin maneuvers flight test data. The results show that implication of IEEMD algorithm on the test data obtained more precise signal extractions with fewer iterations in comparison to EEMD method. The signal is reconstructed by summing the flight modes with more accuracy respect to the EEMD. The IEEMD requires a smaller ensemble size, which results in saving of a significant computational cost.