A Unified Approach to Configuration-based Dynamic Analysis of Quadcopters for Optimal Stability

A special type of rotary-wing Unmanned Aerial Vehicles (UAV), called Quadcopter have prevailed to the civilian use for the past decade. They have gained significant amount of attention within the UAV community for their redundancy and ease of control, despite the fact that they fall under an under-actuated system category. They come in a variety of configurations. The "+" and "x" configurations were introduced first. Literature pertinent to these two configurations is vast. However, in this paper, we define 6 additional possible configurations for a Quadcopter that can be built under either "+" or "x" setup. These configurations can be achieved by changing the angle that the axis of rotation for rotors make with the main body, i.e., fuselage. This would also change the location of the COM with respect to the propellers which can add to the overall stability. A comprehensive dynamic model for all these configurations is developed for the first time. The overall stability for these configurations are addressed. In particular, it is shown that one configuration can lead to the most statically-stable platform by adopting damping motion in Roll/Pitch/Yaw, which is described for the first time to the best of our knowledge.Comment: 6 page, 9 figure

Biodegradation Assessment of Petroleum-Contaminated Soils by Natural Attenuation, Biostimulation and Bioaugmentation Methods on an Industrial Scale

This research study compares the biodegradation of petroleum hydrocarbons by natural attenuation, biostimulation and bioaugmentation methods by applying the Pseudomonas aeruginosa and Bacillus cereus bacteria in hydrocarbon-polluted land area of 1000 square meters consists of three distinct parts to compare the methods discussed above for 100 days. The petroleum-contaminated percentage of this area (w / w) is 0.5%. The extraction and determination of petroleum hydrocarbons percentage in contaminated soil was done by gravimetric method by liquid-liquid extraction method by hexane, dichloromethane and chloroform solvents. The results showed that the bioaugmentation technique has a higher ability to analyze the petroleum hydrocarbons contaminant that reduced about 82.33% of this pollution in the period of 100 days and biostimulation and natural attenuation methods decreased the hydrocarbon materials percentage to the rate of 40.32 and 12.11% respectively

Biodegradation Assessment of Petroleum-Contaminated Soils by Natural Attenuation, Biostimulation and Bioaugmentation Methods on an Industrial Scale

This research study compares the biodegradation of petroleum hydrocarbons by natural attenuation, biostimulation and bioaugmentation methods by applying the Pseudomonas aeruginosa and Bacillus cereus bacteria in hydrocarbon-polluted land area of 1000 square meters consists of three distinct parts to compare the methods discussed above for 100 days. The petroleum-contaminated percentage of this area (w / w) is 0.5%. The extraction and determination of petroleum hydrocarbons percentage in contaminated soil was done by gravimetric method by liquid-liquid extraction method by hexane, dichloromethane and chloroform solvents. The results showed that the bioaugmentation technique has a higher ability to analyze the petroleum hydrocarbons contaminant that reduced about 82.33% of this pollution in the period of 100 days and biostimulation and natural attenuation methods decreased the hydrocarbon materials percentage to the rate of 40.32 and 12.11% respectively

Propeller Performance In Presence Of Freestream

This paper presents mathematical modeling for thrust force and moments generated by a propeller. In particular, the effects of freestream on propeller’s performance are investigated. We introduce some of the applications of the proposed model in modeling multi-rotor UAVs which helps to increase stability or maneuverability of the vehicle. In the end, simulation results for thrust force and moments of an example propeller in presence of a uniform freestream are presented

The Effect of Different Types of Climates on the Spread of COVID-19

Coronavirus disease of 2019 (COVID-19) is the third most common zoonotic disease caused by the coronavirusvirus, SARS in 2002, and Middle East Respiratory Syndrome (MERS) in 2012. The primary origin oftransmission of infection to humans is not well known. However, more prevalence of the disease is caused dueto human-to-human transmission. There are relatively few studies on the impact of climate change on COVID-19 disease in the world. Recognizing the behavioral features of the SARS-CoV-2 virus and its pathogenicity invarious climatic conditions can offer strategies for control measures, preventing the transmission of the disease,and minimizing the potential mortality risk of the virus, which provides a basis for more detailed studies indifferent climatic regions. This study aimed to evaluate the effect of different types of climate on the spread ofCOVID-19

Inhibitory effects of β-cyclodextrin and trehalose on nanofibril and AGE formation during glycation of human serum albumin

The effects of β-cyclodextrin (β-CyD) and trehalose on glycation of human serum albumin (HSA) were studied. These additives reduced AGEs and nanofibril formation of HSA under in vitro glycation conditions and improved its helical structure. These were accomplished through direct interactions of them with HSA and alterations in solute-protein interactions

An inter-laboratory comparison of urinary 3-hydroxypropylmercapturic acid measurement demonstrates good reproducibility between laboratories

<p>Abstract</p> <p>Background</p> <p>Biomarkers have been used extensively in clinical studies to assess toxicant exposure in smokers and non-smokers and have recently been used in the evaluation of novel tobacco products. The urinary metabolite 3-HPMA, a metabolite of the major tobacco smoke toxicity contributor acrolein, is one example of a biomarker used to measure exposure to tobacco smoke. A number of laboratories have developed liquid chromatography with tandem mass spectrometry (LC-MS/MS) based methods to measure urinary 3-HPMA; however, it is unclear to what extent the data obtained by these different laboratories are comparable.</p> <p>Findings</p> <p>This report describes an inter-laboratory comparison carried out to evaluate the comparability of 3-HPMA measurement between four laboratories. A common set of spiked and authentic smoker and non-smoker urine samples were used. Each laboratory used their in-house LC-MS/MS method and a common internal standard. A comparison of the repeatability ('r'), reproducibility ('R'), and coefficient of variation for 3-HPMA demonstrated that within-laboratory variation was consistently lower than between-laboratory variation. The average inter-laboratory coefficient of variation was 7% for fortified urine samples and 16.2% for authentic urine samples. Together, this represents an inter-laboratory variation of 12.2%.</p> <p>Conclusion</p> <p>The results from this first inter-laboratory comparison for the measurement of 3-HPMA in urine demonstrate a reasonably good consensus between laboratories. However, some consistent measurement biases were still observed between laboratories, suggesting that additional work may be required to further reduce the inter-laboratory coefficient of variation.</p