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(R1969) On the Approximation of Eventual Periodicity of Linearized KdV Type Equations using RBF-PS Method
Get PDFWater wave propagation phenomena still attract the interest of researchers from many areas and with various objectives. The dispersive equations, including a large body of classes, are widely used models for a great number of problems in the fields of physics, chemistry and biology. For instance, the Korteweg-de Vries (KdV) equation is one of the famous dispersive wave equation appeared in the theories of shallow water waves with the assumption of small wave-amplitude and large wave length, also its various modifications serve as the modeling equations in several physical problems. Another interesting qualitative characteristic of solutions of some dispersive wave equations indicated through experiments that are connected with their large-time behavior termed as Eventual Time Periodicity which is exhibited by solutions of initial-boundary-value problems (IBVPs henceforth). Laboratory experiments in a channel with a flap-type or piston-type wave maker mounted at one end of a channel exposed this interesting phenomena. Here in this study we numerically investigate the solutions periodicity for linearized KdV type equations on a finite (bounded) domain with periodic boundary conditions using meshfree technique known as Radial basis function pseudo spectral (RBF-PS) method
X-Ray Radiation Effects On Unfunctionalized And Functionalized Swcnt/Pmma Thin Film Nanocomposites For Radiation Sensor Applications
No full textSingle-walled carbon nanotube (SWCNT) and poly (methyl methacrylate) (PMMA) nanocomposites have various potential applications including radiation detection. This work studied the response of a radiation sensor that was developed from functionalized and unfunctionalized SWCNT/PMMA nanocomposite thin films placed on an interdigitated electrode (IDE). The functionalized thin film devices are made of ferrocene doped SWCNTs, SWCNTs functionalized with carboxylic acid (COOH), and SWCNTs coated/ modified with copper.
This study focused on studying the effect of ionizing radiation (X-rays) in the real-time electrical resistance of thin film nanocomposites. The initial positive results observed in the previous study on X-ray radiation effect on MWCNT/PMMA can be reproduced. The SWCNT/PMMA nanocomposite was prepared using the solution blending method. The prepared thin film of nanomaterial composite in this study was cast on IDE to make the SWCNT/PMMA nanocomposite thin film device. A 160 KV X-ray source was used to irradiate the thin film device at different doses and dose rates. X-rays generated electrons and positive ions (equivalent to holes) in the nanocomposite film caused the reduction of the device’s resistance.
The electrical characterization of the device was performed using a Semiconductor Device Analyzer during the experiments. The results showed that heat treatment of irradiated nanocomposite devices caused rapid recovery. The heat treatment time of thin film device increased about linearly, increasing with the X-rays radiation dose. The thin film device was operated at dc voltage as low as 0.05 V and could reliably observe the radiation-induced change in electrical resistance. This study suggests that researchers could use SWCNT/PMMA thin film devices to detect X-rays radiation, with five times higher sensitivity than similar devices made with MWCNT/PMMA nanocomposite thin film in another study. The response of carboxylic acid functionalized and copper coated SWCNT/PMMA nanocomposite thin film devices to X-rays reduced compared to unfunctionalized SWCNT/PMMA nanocomposite with almost a factor or two for all dose rate conditions. The sensitivity of ferrocene doped SWCNT/PMMA was the highest of all other functionalized and unfunctionalized SWCNT/PMMA thin film devices at lower dose rates 2.13 krad/min and 1.08 krad/min. In contrast, a previous study showed the improved response of the functionalized MWCNT/PMMA nanocomposite devices to X-ray ionizing radiation compared to unfunctionalized MWCNT/PMMA nanocomposite devices for all dose rates. In addition, electrical characterization of thin SWCNT/PMMA film devices was performed using an Arduino Nano microcontroller board.
The results showed that an inexpensive, lightweight-designed prototype radiation sensor instrument consisting of using SWCNT/PMMA thin film nanocomposite can be produced by integrating the devices with a modest microcontroller. The thin film device (SWCNT/PMMA) was irradiated with gamma radiation (Cs-137) to study the low dose rate radiation effect on the device. There was no significant effect observed on the electrical resistance of the device due to gamma radiation. The device was interfaced with an Arduino nano microcontroller connected to a DHT11 temperature and humidity sensor to monitor humidity and change in resistance of the device under ambient conditions in real-time. When the device is open, resistance change is about -2.5% under ambient conditions. The decrease in resistance when the device is encapsulated is very small (about -0.1%). In addition, the result showed that the encapsulated device could be used to detect X-ray radiation. Future work may focus on encapsulating the device to isolate the device from the environment to reliably detect low dose rates
Functional variables of bull sperm associated with cryotolerance
No full textThe objective of this study was to ascertain sperm population and cellular characteristics as well as total antioxidant capacity in spermatozoa from Holstein bulls with Good (11 bulls) and Poor (5 bulls) cryotolerance. Post-thaw sperm kinetics were evaluated using CASA, membrane integrity was assessed via HOS test, and DNA fragmentation was measured using the HaloSperm kit. Data were analyzed using principal component analysis. The spermatozoa from Good bulls had a higher number of cells with intact membranes (P=0.029), non-fragmented DNA (P=0.018), and post-thaw viability (P\u3c0.001) compared to sperm cells from Poor cryotolerance bulls. Sperm cells from Good bulls also had a faster average path velocity (P=0.017) and straight-line velocity (P=0.036), along with a greater distance average path (P=0.006) and distance straight line (P=0.011). However, total antioxidant capacity, number of live cells, and other kinetic parameters between spermatozoa from Good and Poor groups were not different. There is no one specific sperm function variable alone that can accurately predict cryotolerance of bull spermatozoa, and thus, a combination of sperm cell attributes and kinematics needs to be utilized by the AI industry in differentiating between freezability of spermatozoa between bulls
Harnessing the value of rumen protected amino acids to enhance animal performance
No full textIn general, higher mammals need nine amino acids in their diets as building blocks to synthesize proteins while ruminants can produce some of them through the synthesis of microbial proteins. Diet is utilized by ruminal microorganisms to synthesize microbial protein (MCP) which is digested in the small intestine (SI). Although protein and amino acid requirements in ruminants are subject to microbial protein synthesis, it is not enough for optimal daily production. Therefore, there is a current trend towards supplementing amino acids in ruminant diets. In the rumen, free amino acids can be degraded by rumen bacteria, therefore, the AAs need to be supplemented in a protected form to be stable in the rumen and absorbable post-ruminal for metabolic purposes. The main site of amino acid absorption is the small intestine (SI), and there is a need to keep AA from ruminal degradation and direct them to absorption sites. Several approaches have been suggested by feed scientists to decrease this problem such as defaunation and debacterization of the rumen against amino acid-fermenting fungi and bacteria, inhibitors or antagonists of vitamin B6 enzymes, diet composition and also protecting AA from rumen degradation. A number of studies have evaluated the roles of amino acids concerning their effects on milk yield, growth, digestibility, feed intake and efficiency of nitrogen utilization of ruminants. The focus of this review was on experimental and research studies about AAs in feedstuff, metabolism, supplementing amino acids for ruminants and the current trends of using rumen protected amino acids
Adaptive Hybrid Projective Synchronization Of Hyper-chaotic Systems
Get PDFIn this paper, we design a procedure to investigate the hybrid projective synchronization (HPS) technique among two identical hyper-chaotic systems. An adaptive control method (ACM) is pro- posed which is based on Lyapunov stability theory (LST). The considered technique globally determines the asymptotical stability and establishes identification of parameter simultaneously via HPS approach. Additionally, numerical simulations are carried out for visualizing the effectiveness and feasibility of discussed scheme by using MATLAB
Qualitative Analysis of a Modified Leslie-Gower Predator-prey Model with Weak Allee Effect II
Get PDFThe article aims to study a modified Leslie-Gower predator-prey model with Allee effect II, affecting the functional response with the assumption that the extent to which the environment provides protection to both predator and prey is the same. The model has been studied analytically as well as numerically, including stability and bifurcation analysis. Compared with the predator-prey model without Allee effect, it is found that the weak Allee effect II can bring rich and complicated dynamics, such as the model undergoes to a series of bifurcations (Homoclinic, Hopf, Saddle-node and Bogdanov-Takens). The existence of Hopf bifurcation has been shown for models with (with- out) Allee effect and the local existence and stability of the limit cycle emerging through Hopf bifurcation has also been studied. The phase portrait diagrams are sketched to validate analytical and numerical findings
Theoretical Study of Mach number and Compressibility Effect on the Slender Airfoils
Get PDFTheoretical development of the velocity potential equation for compressible flow and its various consequences has been presented. The geometrical interpretation of potential equation and conformal mapping technique are discussed where the mappings link the flow around a circular cylinder of a slender airfoil. The lift and drag coefficients are determined for the slender airfoils based on the Mach number and compressibility effects. The calculated lift coefficients show that with the increasing of attack angle it increases linearly and a higher lift coefficient is found for a smaller Mach number for any certain attack angle. Similarly, the drag profiles are determined which are exponentially decreased with the increasing of Mach number for any fixed attack angle. The calculated and experimental data on the lift and drag coefficients over the slender airfoil surface are compared and found in good agreement
Numerical Technique for Solving Fractional-order of IVGTT Glucose-insulin Interaction
Get PDFIn this paper, we use a numerical technique to solve fractional nonlinear differential equations systems that arise in Bergman’s minimal model that describe blood glucose and insulin metabolism, after intravenous tolerance testing. Shifted Jacobi -Gauss-Radau collocation (SJ-GR-C) method is developed for approximating the proposed model. The principal target in our technique is to transform the proposed model to a system of algebraic equations. Finally, numerical simulation is introduced to illustrate the analytical results
Somaesthetics of discomfort enhancing awareness and inquiry
No full textThis essay presents somaesthetics of discomfort as an extension of the field of somaesthetics as developed by Shusterman. Using the work of Peirce and Dewey as a foundation upon which Shusterman and Johnson have considered the body as the basis of aesthetics, I propose that somaesthetics of discomfort provides a means of enhancing bodily awareness and reflection useful for domains of inquiry, such as healthcare and design. Taking Peirce\u27s notion of the irritation of doubt in a literal sense, I explore bodily discomfort as the inception of inquiry. I consider work done by phenomenologists concerning experiences of comfort and discomfort, which includes definitions of each. My argument follows the perspective put forth by Peirce, Dewey, and contemporary pragmatists that experience is qualitative and that feeling is at the root of reflection. I explain how discomfort may be considered a type of aesthetic experience and provide examples of bodily discomfort as somaesthetic. In closing, I consider somaesthetic focus on discomfort as fostering moral imagination and empathy