Modeling and control of probe-on-probe dynamics in dual-probe atomic force microscopy

“The atomic force microscope (AFM) is a widely used instrument for imaging and direct manipulation of materials and particles at the nanoscale. The AFM uses a probe, which is a microcantilever with a sharp point at the end. Typically, the AFM is constructed with a single probe. The disadvantage of this construction is that it can only be used either for imaging or manipulation in one implementation. An AFM was constructed using two probes, permitting simultaneous imaging and manipulation. A dual-probe AFM (DP-AFM) provides a foundation for feedback controlled manipulation. Paper I investigates probe-on-probe contact stability and examines the dynamics of probe-on-probe contact. Evaluation of these interactions leads to study the stability of state-dependent switched systems. Uniform ultimate boundedness theorem and sequence nonincreasing condition corollary were employed to show stability of proposed state dependent switched model with DP-AFM application. Paper II is extending approach-retract curve to characterize probe-on-probe interaction. Universal sensitivity model for probe-on-probe interaction was found. During the retract phase, adhesion occurs between probes. Jump-off-contact deflection between probes was employed for adhesion force calculation. Paper III represents implementation of Iterative Learning Control on Z-axis nanostage with stochastic and deterministic noise. The nano stage model was identified using frequency response of the stage. Deterministic and stochastic noise spectrum was identified experimentally. Optimal Q filter and learning filter (L-filter) were designed depending on the deterministic and stochastic noise spectrum. The error norm was experimentally found to be converging for all four ILC algorithms”--Abstract, page iv

The Desarguesian projective plane of order eleven and related codes

In a finite projective plane PG(2; q), a set K of k points is a (k; n)-arc for 2 ≤ n ≤ q - 1 if the following two properties hold: 1. Every line intersects K in at most n points. 2. There exists a line which intersects K in exactly n points. Algebraic curves of degree n give examples of (k; n)-arc; the parameter n is called the degree of the arc. In PG(2; q); the problem of finding mn(2; q) and tn(2; q) (the maximum and the minimum value of k for which a complete (k; n)-arc exists) and the problem of classifying such arcs up to projective equivalence, are crucial problems in finite geometry. One of the important application of these arcs in coding theory are projective codes that cannot be extended to larger codes. The aim of this project is to classify (k; n)-arcs if possible for 3 ≤ n ≤ 5 and to construct large arcs in PG(2; 11): Algebraic and new combinatorial methods are used to perform the classification and the construction of such arcs with different degrees. Those procedures are implemented using different open-source software packages such as GAP [35] and Orbiter [10]. We were successful in obtaining new isomorphism types of (k; 5)-arcs for k = 5,…, 13 in PG(2; 11): We have also developed a new classification algorithm for cubic curves in small projective planes. Moreover, a new upper bound is proved for the number of 5-secants of (45; 5)-arc. In addition to proving our new lower bound for the complete (k; 5)-arc in PG(2; 11): The non existence of (44; 5)-arc and (45; 5)-arc is formulated as a new conjecture for q = 11: Using an arc of degree 2 and exploiting the complement relation between arcs and blocking sets we find new 134 isomorphism types of (77; 8)-arcs in PG(2; 11)

Detecting the antibacterial activity of green synthesized silver (Ag) nanoparticles functionalized with ampicillin (Amp)

In the current study, synthesis and characterization of silver nanoparticles (AgNPs) before and after functionalization with ampicillin antibiotic and their application as anti-pathogenic agents towards bacteria were investigated. AgNPs were synthesized by a green method from AgNO3 solution with glucose subjected to microwave radiation. Characterization of the nanoparticles was conducted using UV-Vis spectroscopy, scanning electron microscopy (SEM), zeta potential determination and Fourier transform infrared (FTIR) spectroscopy. From SEM analysis, the typical silver nanoparticle particle size was found to be 30 nm and Zeta potential measurements gave information about particle stability. Analysis of FTIR patterns and UV-VIS spectroscopy confirmed the production of nanosilver particles. The activity of produced silver NP was tested against three pathogens (Escherichia coli, Staphylococcus aureus, and Acinetobacter baumannii) in both liquid and solid growth medium. AgNPs presented potential antibacterial activity, against tested bacteria. Ag and Ag-AMP nanoparticles were detected to have penitent antimicrobial. The optical density (OD) of the culture solution and measuring zones of inhibition were used to monitor the growth of bacteria in liquid and solid growth medium respectivel

Defuzzification of groups of fuzzy numbers using data envelopment analysis

Defuzzification is a critical process in the implementation of fuzzy systems that converts fuzzy numbers to crisp representations. Few researchers have focused on cases where the crisp outputs must satisfy a set of relationships dictated in the original crisp data. This phenomenon indicates that these crisp outputs are mathematically dependent on one another. Furthermore, these fuzzy numbers may exist as a group of fuzzy numbers. Therefore, the primary aim of this thesis is to develop a method to defuzzify groups of fuzzy numbers based on Charnes, Cooper, and Rhodes (CCR)-Data Envelopment Analysis (DEA) model by modifying the Center of Gravity (COG) method as the objective function. The constraints represent the relationships and some additional restrictions on the allowable crisp outputs with their dependency property. This leads to the creation of crisp values with preserved relationships and/or properties as in the original crisp data. Comparing with Linear Programming (LP) based model, the proposed CCR-DEA model is more efficient, and also able to defuzzify non-linear fuzzy numbers with accurate solutions. Moreover, the crisp outputs obtained by the proposed method are the nearest points to the fuzzy numbers in case of crisp independent outputs, and best nearest points to the fuzzy numbers in case of dependent crisp outputs. As a conclusion, the proposed CCR-DEA defuzzification method can create either dependent crisp outputs with preserved relationship or independent crisp outputs without any relationship. Besides, the proposed method is a general method to defuzzify groups or individuals fuzzy numbers under the assumption of convexity with linear and non-linear membership functions or relationships

Performance analysis of negative group delay network using MIMO technique

This study introduces comparative consequences that determine the bit error rate enhancements, resultant from adopting a proposed MIMO wireless model in this study. The antenna configurations for this model uses new small microstrip slotted patch antenna with multiple frequency bands at strategic operating frequencies of 2.4, 4.4, and 5.55 respectively. The S11 response of the proposed antenna for IEEE802.11 MIMO wireless network has been highly appropriate to be adopted with MIMO antenna system. The negative group delay (NGD) response is the most significant feature for projected MIMO antenna. The NGD stands for a counterintuitive singularity that interacts time advancement with wave propagation. These improvements are employed for increasing a reliability of instantly conveyed data streams, enhance the capacity of the wireless configuration and decrease the bit error rate (BER) of adopted wireless system. In addition to antenna scattering response, the enhancements have been analysed in term of BER for different MIMO topologies

Early Baldness in Males and Hormonal Changes

Androgenetic alopecia (AGA) or baldness is a common form of hair loss, affecting men more than women .The exact causes and pathogenesis of baldness are not well understood. A search for new drug is still needed. This study aims to evaluate the role of gonadotropins hormones in hair loss in males and its possibility to be used as treatment target. A total of 78 volunteers 43 with baldness and 35 healthy men were participated in this study. Their age ranged between (20-49) years, the studied groups were divided into two categories: firstly according to age (group1: 20-29 year), (group2: 30-39 year),and (group3: 40-49 year).Secondly according to baldness degree. LH and FSH were measured by using Enzyme Linked Immunosorbent Assay (ELISA) kits. The results showed a significant decrease (

Investigation the Morphological Characteristics of the Particulate Matter Emissions from the Oxygenated Fuels Combustion in Diesel Engines

Understanding the size and morphological properties of particulate matter (PM) is essential to improve analysis of the process of PM formation in diesel engines. These will help to reduce undesirable environmental impact and health effects. A scanning mobility particle sizer (SMPS) and thermal gravimetric analysis (TGA) were used to study the changes in size characteristics of PM/soot and soot reactivity. Furthermore, improve the oxidation of soot particles in diesel engines is necessary under the range of different fuel combustions. Oxygenated fuels (e.g., ethanol blend, E10 and butanol blend, B16) were used in this experimental study to show how insignificant changes in morphological characteristics and activity of PM. The oxidation and activation energy of PM was achieved at the lower temperature from the combustion of oxygenated fuels compared with diesel fuel combustion. Besides, it was found that both the size of soot particulate and the number of primary particles are reduced with increasing the oxygen content in oxygenated fuels than the diesel fuel. The shape of primary soot particle for PM is a bit more spherical in the case of diesel fuel than to the oxygenated fuels

MICRO DETERMINATION OF DOPAMINE IN BIOLOGICAL SAMPLES BY COUPLING REACTION

The paper presents the development of an analytical method to determine dopamine by coupling reaction with diazotized solution of 4-Aminoantipyrine in basic media to give a compound with a single azo dye salt having orange color soluble in water. A calibration curve for a range of concentration (9.14x10-5 – 2.28x10-3 μg.mL-1) was realized and the value of molar absortivity was 1.5x103 L.mol-1.cm-1, with a relative standard deviation more than 1.26% and a recovery 98.77%. As we study the nature of the azo dye by mole fraction method, from the practical value we found that the mole fraction of the dye compound is 1:1 (dopamine: 4- amino antipyrine) and the stability factor reach to 1.4x106 L.mol-1. The described procedure is very simple, low-time-consuming, provides high throughput of examined samples, and could be used for routine screening and confirmatory analyses as well. The method was successfully validated to the analysis of the dopamine in biological samples

MICRO DETERMINATION OF DOPAMINE IN BIOLOGICAL SAMPLES BY COUPLING REACTION

The paper presents the development of an analytical method to determine dopamine by coupling reaction with diazotized solution of 4-Aminoantipyrine in basic media to give a compound with a single azo dye salt having orange color soluble in water. A calibration curve for a range of concentration (9.14x10-5 – 2.28x10-3 μg.mL-1) was realized and the value of molar absortivity was 1.5x103 L.mol-1.cm-1, with a relative standard deviation more than 1.26% and a recovery 98.77%. As we study the nature of the azo dye by mole fraction method, from the practical value we found that the mole fraction of the dye compound is 1:1 (dopamine: 4- amino antipyrine) and the stability factor reach to 1.4x106 L.mol-1. The described procedure is very simple, low-time-consuming, provides high throughput of examined samples, and could be used for routine screening and confirmatory analyses as well. The method was successfully validated to the analysis of the dopamine in biological samples

A modified empirical model for estimating the wetted zone dimensions under drip irrigation

Drip irrigation system has become one of the most common irrigation systems especially in arid and semi-arid regions due to its advantages in saving water. One of the most essential considerations in designing these systems is the dimensions of the wetted soil volume under emitters. These dimensions are significant in choosing the proper emitter spacing along the laterals and the suitable distance between laterals. In this study, a modified empirical equations for estimating the horizontal and vertical extend of the wetted zone under surface emitters were suggested. Data from published papers includes different conditions of soil properties and emitter discharge were used in deriving the empirical model using the nonlinear regression. The developed model has high value for coefficient of determination, R2. The results from the developed model were compared with results of other empirical models derived by other researchers. Some statistical criteria were used to evaluate the model performance which are the mean error ME, root mean square error RMSE, and model efficiency EF. The results revealed that the modified model showed good performance in predicting the wetted zone dimensions and it can be used in design and management of drip irrigation systems