Search results for: magnetic field therapy

Authors: Eyüphan Manay, Bayram Sahin, Emre Mandev, Ibrahim Ates, Tuba Yetim

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In this study, it was aimed to determine the thermophysical properties of two different magnetic nanofluids (NiFe₂O₄-water and CoFe₂O₄-water). Magnetic nanoparticles were dispersed into the pure water at different volume fractions from 0 vol.% to 4 vol.%. The measurements were performed in the temperature range of 15 ^oC-55 ^oC. In order to get better idea on the temperature dependent thermophysical properties of magnetic nanofluids (MNFs), viscosity and thermal conductivity measurements were made. SEM images of both NiFe₂O₄ and CoFe₂O₄ nanoparticles were used in order to confirm the average dimensions. The measurements showed that the thermal conductivity of MNFs increased with an increase in the volume fraction as well as viscosity. Increase in the temperature of both MNFs resulted in an increase in the thermal conductivity and a decrease in the viscosity. Based on the measured data, the correlations for both the viscosity and the thermal conductivity were presented with respect to solid volume ratio and temperature. Effective thermal conductivity of the prepared MNFs was also calculated. The results indicated that water based NiFe₂O₄ nanofluid had higher thermal conductivity than that of the CoFe₂O₄. Once the viscosity values of both MNFs were compared, almost no difference was observed.

Keywords: Magnetic nanofluids, thermal conductivity, Viscosity, NiFe2O4-water, CoFe2O4-water.

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Authors: Takahiro Nakamura, Kenji Takahashi, Hiroyuki Nishida, Shunjiro Shinohara, Takeshi Matsuoka, Ikkoh Funaki, Takao Tanikawa, Tohru Hada

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In order to realize long-lived electric propulsion systems, we have been investigating an electrodeless plasma thruster. In our concept, a helicon plasma is accelerated by the magnetic nozzle for the thrusts production. In addition, the electromagnetic thrust can be enhanced by the additional radio-frequency rotating electric field (REF) power in the magnetic nozzle. In this study, a direct measurement of the electromagnetic thrust and a probe measurement have been conducted using a laboratory model of the thruster under the condition without the REF power input. Fromthrust measurement, it is shown that the thruster produces a sub-milli-newton order electromagnetic thrust force without the additional REF power. The thrust force and the density jump are observed due to the discharge mode transition from the inductive coupled plasma to the helicon wave excited plasma. The thermal thrust is theoretically estimated, and the total thrust force, which is a sum of the electromagnetic and the thermal thrust force and specific impulse are calculated to be up to 650 μN (plasma production power of 400 W, Ar gas mass flow rate of 1.0 mg/s) and 210 s (plasma production power of 400 W, Ar gas mass flow rate of 0.2 mg/s), respectively.

Keywords: Electric propulsion, Helicon plasma, Lissajous acceleration, Thrust stand.

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Authors: Alexander Schulz, Ingrid Rottensteiner, Manfred Neumann, Michael Wehse, Johann Wassermann

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Self-sensing estimates the air gap within an electro magnetic path by analyzing the bearing coil current and/or voltage waveform. The self-sensing concept presented in this paper has been developed within the research project “Active Magnetic Bearings with Supreme Reliability" and is used for position sensor fault detection. Within this new concept gap calculation is carried out by an alldigital analysis of the digitized coil current and voltage waveform. For analysis those time periods within the PWM period are used, which give the best results. Additionally, the concept allows the digital compensation of nonlinearities, for example magnetic saturation, without degrading signal quality. This increases the accuracy and robustness of the air gap estimation and additionally reduces phase delays. Beneath an overview about the developed concept first measurement results are presented which show the potential of this all-digital self-sensing concept.

Keywords: digital signal analysis, active magnetic bearing, reliability, fault detection.

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Authors: A. Faro, D. Giordano, M. Pennisi, G. Scarciofalo, C. Spampinato, F. Tramontana

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The paper proposes a methodology to process the signals coming from the Transcranial Magnetic Stimulation (TMS) in order to identify the pathology and evaluate the therapy to treat the patients affected by demency diseases. In particular, a fuzzy model is developed to identify the demency of the patients affected by Subcortical Ischemic Vascular Dementia and to measure the positive effect, if any, of a repetitive TMS on their motor performances. A tool is also presented to support the mentioned analysis.

Keywords: TMS, SIVD, Electromiography , Fuzzy Logic.

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Authors: B. Parchem, M. Watanabe, D. Modrakovic, L. Mathew, A. Franklin, M. Cao, R. E. Broudy

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Objective: Executive functioning (EF) deficits underlie several mental health diagnoses including ADHD, anxiety, and depression. Community mental health clinics face extensive waitlists for services with many referrals involving EF deficits. A pilot trial of a four-week group therapy was developed using key components from Cognitive-Behavioral Therapy (CBT), Dialectical Behavior Therapy (DBT), and mindfulness with an aim to improve EF skills and offer low-fee services. Method: Eight adults (M = 34.5) waiting for services at a community clinic were enrolled in a four-week group therapy at an in-house training clinic for doctoral trainees. Baseline EF, pre-/post-intervention ADHD and distress symptoms, group satisfaction, and curriculum helpfulness were assessed. Results: Downward trends in ADHD and distress symptoms pre/post-intervention were not significant. Favorable responses on group satisfaction and helpfulness suggest clinical utility. Conclusion: Preliminary pilot data from a brief group therapy to improve EF may be an efficacious, acceptable, and feasible intervention for adults waiting for services at community mental health and training clinics where there are high demands and limits to services and staffs.

Keywords: Executive functioning, cognitive-behavioral therapy, dialectical behavior therapy, mindfulness, adult group therapy.

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Authors: Robert Pintaric, Joze Matela, Stefan Pintaric, Stanka Vadnjal

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Introduction: This work is aimed to represent the use of the OPTI-JET CS MD1 MR prototype for application of neutral electrolyzed oxidizing water (NEOW) in magnetic resonance rooms. Material and Methods: We produced and used OPTI-JET CS MD1 MR aerosolisator whereby was performed aerosolization. The presence of microorganisms before and after the aerosolisation was recorded with the help of cyclone air sampling. Colony formed units (CFU) was counted. Results: The number of microorganisms in magnetic resonance 3T room was low as expected. Nevertheless, a possible CFU reduction of 87% was recorded. Conclusions: The research has shown that the use of EOW for the air and hard surface disinfection can considerably reduce the presence of microorganisms and consequently the possibility of hospital infections. It has also demonstrated that the use of OPTI-JET CS MD1 MR is very good. With this research, we started new guidelines for aerosolization in magnetic resonance rooms. Future work: We predict that presented technique works very good but we must focus also on time capacity sensors, and new appropriate toxicological studies.

Keywords: Biocide, electrolyzed oxidizing water (EOW), disinfection, microorganisms, OPTI-JET CS MD1MR.

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Authors: Ziya Uddin

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This paper deals with the theoretical and numerical investigation of magneto hydrodynamic boundary layer flow of a nanofluid past a wedge shaped wick in heat pipe used for the cooling of electronic components and different type of machines. To incorporate the effect of nanoparticle diameter, concentration of nanoparticles in the pure fluid, nanothermal layer formed around the nanoparticle and Brownian motion of nanoparticles etc., appropriate models are used for the effective thermal and physical properties of nanofluids. To model the rotation of nanoparticles inside the base fluid, microfluidics theory is used. In this investigation ethylene glycol (EG) based nanofluids, are taken into account. The non-linear equations governing the flow and heat transfer are solved by using a very effective particle swarm optimization technique along with Runge-Kutta method. The values of heat transfer coefficient are found for different parameters involved in the formulation viz. nanoparticle concentration, nanoparticle size, magnetic field and wedge angle etc. It is found that, the wedge angle, presence of magnetic field, nanoparticle size and nanoparticle concentration etc. have prominent effects on fluid flow and heat transfer characteristics for the considered configuration.

Keywords: Heat transfer, Heat pipe, numerical modeling, nanofluid applications, particle swarm optimization, wedge shaped wick.

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Authors: A. V. Trukhanov, S. V. Trukhanov, L. V. Panina, V. G. Kostishin, V. A. Turchenko

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It has been shown that BaFe₁₂O₁₉ is a perspective room-temperature multiferroic material. A large spontaneous polarization was observed for the BaFe₁₂O₁₉ ceramics revealing a clear ferroelectric hysteresis loop. The maximum polarization was estimated to be approximately 11.8 μC/cm². The FeO₆ octahedron in its perovskite-like hexagonal unit cell and the shift of Fe³⁺ off the center of octahedron are suggested to be the origin of the polarization in BaFe₁₂O₁₉. The magnetic field induced electric polarization has been also observed in the doped BaFe_12-x-δSc_xM_δO₁₉ (δ=0.05) at 10 K and in the BaSc_xFe_12−xO₁₉ and SrSc_xFe_12−xO₁₉ (x = 1.3–1.7) M-type hexaferrites. The investigated BaFe_12-xD_xO₁₉ (x=0.1, D-Al³⁺, In³⁺) samples have been obtained by two-step “topotactic” reactions. The powder neutron investigations of the samples were performed by neutron time of flight method at High Resolution Fourier Diffractometer.

Keywords: Substituted hexaferrites, ferrimagnetics, ferroelectrics, neutron powder diffraction, crystal and magnetic structures.

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Authors: Leila Amjad, Mahsa Shafighi

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The role of the pollen grain, with to the reproductive process of higher plants, is to deliver the spermatic cells to the embryo sac for egg fertilization. The aim of this project was study the effect of electromagnetic fields on structure and pollen grains development in Chenopodium album. Anthers of Chenopodium album L. were collected at different stages of development from control (without electromagnetic field) and plants grown at 10m from the field sources. Structure and development of pollen grains were studied and compared. The studying pollen structure by Light and Scanning electron microscopy showed that electromagnetic fields reduction of pollen grains number and male sterility, thus , in some anthers, pollen grains were attached together and deformed compared to control ones. The data presented suggest that prolonged exposures of plants to magnetic field may cause different biological effects at the cellular tissue and organ levels.

Keywords: Electromagnetic fields, pollen, Chenopodium albumL.

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Authors: Diako Azizi, Hosein Heydari, Ahmad Gholami

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Today with the rapid growth of telecommunications equipment, electronic and developing more and more networks of power, influence of electromagnetic waves on one another has become hot topic discussions. So in this article, this issue and appropriate mechanisms for EMC operations have been presented. First, a source of alternating current (50 Hz) and a clear victim in a certain distance from the source is placed. With this simple model, the effects of electromagnetic radiation from the source to the victim will be investigated and several methods to reduce these effects have been presented. Therefore passive and active shields have been used. In some steps, shielding effectiveness of proposed shields will be compared. . It should be noted that simulations have been done by the finite element method (FEM).

Keywords: Electrical field, field distribution, finite element method, shielding effectiveness

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Authors: Asadollah Boshra, Ahmad Seif, Mehran Aghaei

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A model of (4, 4) single-walled boron-nitride nanotube as a representative of armchair boron-nitride nanotubes studied. At first the structure optimization performed and then Nuclear Magnetic Resonance parameters (NMR) by Density Functional Theory (DFT) method at 11B and 15N nuclei calculated. Resulted parameters evaluation presents electrostatic environment heterogeneity along the nanotube and especially at the ends but the nuclei in a layer feel the same electrostatic environment. All of calculations carried out using Gaussian 98 Software package.

Keywords: Boron-nitride nanotube, Density Functional Theory, Nuclear Magnetic Resonance (NMR).

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Authors: P. Ram Mohan, M. Vijaya Kumar, O. V. Raghava Reddy

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This paper deals with the simulation of a Boost Power Factor Correction (PFC) Converter with Electro Magnetic Interference (EMI) Filter. The diode rectifier with output capacitor gives poor power factor. The Boost Converter of PFC Circuit is analyzed and then simulated with diode rectifier. The Boost PFC Converter with EMI Filter is simulated for resistive load. The power factor is improved using the proposed converter.

Keywords: Boost Converter, Power Factor Correction, Electro Magnetic Interference, Diode Rectifier

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Authors: Jo-Chi Jao, Yen-Ku Chen, Twei-Shiun Jaw, Po-Chou Chen

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This study aimed to investigate the magnetic resonance (MR) signal enhancement ratio (ER) of contrast-enhanced MR angiography (CE-MRA) in normal rats with gadobenate dimeglumine (Gd-BOPTA) using a clinical 3T scanner and an extremity coil. The relaxivities of Gd-BOPTA with saline only and with 4.5% human serum albumin (HSA) were also measured. Compared with Gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA), Gd-BOPTA had higher relaxivities. The maximum ER of aorta (ERa), kidney, liver and muscle with Gd-BOPTA were higher than those with Gd-DTPA. The maximum ERa appeared at 1.2 min and decayed to half at 10 min after Gd-BOPTA injection. This information is helpful for the design of CE-MRA study of rats.

Keywords: Contrast-Enhanced Magnetic Resonance Angiography, Gd-BOPTA, Gd-DTPA, Rat.

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Authors: H. Nouri, I. E. Achouri, A. Grimes, H. Ait Said, M. Aissou, Y. Zebboudj

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This paper aims to analysis the behavior of DC corona discharge in wire-to-plate electrostatic precipitators (ESP). Currentvoltage curves are particularly analyzed. Experimental results show that discharge current is strongly affected by the applied voltage. The proposed method of current identification is to use the method of least squares. Least squares problems that of into two categories: linear or ordinary least squares and non-linear least squares, depending on whether or not the residuals are linear in all unknowns. The linear least-squares problem occurs in statistical regression analysis; it has a closed-form solution. A closed-form solution (or closed form expression) is any formula that can be evaluated in a finite number of standard operations. The non-linear problem has no closed-form solution and is usually solved by iterative.

Keywords: Electrostatic precipitator, current-voltage characteristics, Least Squares method, electric field, magnetic field.

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Authors: Ane Larrea, Victor Sebastian, Manuel Arruebo, Jesus Santamaria

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We present a gas-liquid microfluidic system as a reactor to obtain magnetite nanoparticles with an excellent degree of control regarding their crystalline phase, shape and size. Several types of microflow approaches were selected to prevent nanomaterial aggregation and to promote homogenous size distribution. The selected reactor consists of a mixer stage aided by ultrasound waves and a reaction stage using a N2-liquid segmented flow to prevent magnetite oxidation to non-magnetic phases. A milli-fluidic reactor was developed to increase the production rate where a magnetite throughput close to 450 mg/h in a continuous fashion was obtained.

Keywords: Microfluidics, magnetic nanoparticles, continuous production, nanomaterials.

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Authors: P. Pistelok

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The article presents the concept of an electromagnetic circuit generator with permanent magnets mounted on the surface rotor core designed for single phase work. Computation field-circuit model was shown. The spectrum of time course of voltages in the idle work was presented. The cross section with graphically presentation of magnetic induction in particular parts of electromagnetic circuits was presented. Distribution of magnetic induction at the rated load point for each phase was shown. The time course of voltages and currents for each phases for rated power were displayed. An analysis of laboratory results and measurement of load characteristics of the generator was discussed. The work deals with three electromagnetic circuits of generators with permanent magnet where output voltage characteristics versus rated power were expressed.

Keywords: Permanent magnet generator, permanent magnets, vibration, course of torque, single phase work, asymmetrical three phase work.

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Authors: Wei Chin, Wen-Kuang Hsu

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Fats and oils are made of esterified hydrocarbons (RCOOR-) and this work demonstrates the substitution of R by multi-walled CNTs (MWNTs). The resultant materials are fluidic, oily, electrically conducting and excellent lubricants. Esterified MWNTs can also respond to magnetic field when tubules contain long segments of Fe

Keywords: Liquids Nanomaterials Electric conductors

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Authors: Yasmin Binti Othman Mydin, Mohd. Fadzillah Abdul Razak

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Rational Emotive Behaviour Therapy is the first cognitive behavior therapy which was introduced by Albert Ellis. This is a systematic and structured psychotherapy which is effective in treating various psychological problems. A patient, 25 years old male, experienced intense fear and situational panic attack to return to his faculty and to face his class-mates after a long absence (2 years). This social anxiety disorder was a major factor that impeded the progress of his study. He was treated with the use of behavioural technique such as relaxation breathing technique and cognitive techniques such as imagery, cognitive restructuring, rationalization technique and systematic desensitization. The patient reported positive improvement in the anxiety disorder, able to progress well in studies and lead a better quality of life as a student.

Keywords: Anxiety, behaviour, cognitive, therapy

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Authors: K. Dimitropoulos, N. Grammalidis, I. Gragopoulos, H. Gao, Th. Heuer, M. Weinmann, S. Voit, C. Stockhammer, U. Hartmann, N. Pavlidou

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Existing ground movement surveillance technologies at airports are subjected to limitations due to shadowing effects or multiple reflections. Therefore, there is a strong demand for a new sensing technology, which will be cost effective and will provide detection of non-cooperative targets under any weather conditions. This paper aims to present a new intelligent system, developed within the framework of the EC-funded ISMAEL project, which is based on a new magnetic sensing technology and provides detection, tracking and automatic classification of targets moving on the airport surface. The system is currently being installed at two European airports. Initial experimental results under real airport traffic demonstrate the great potential of the proposed system.

Keywords: Air traffic management, magnetic sensors, multitracking, A-SMGCS.

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Authors: M. Bahgat, F. M. Awan, H. A. Hanafy, O. N. Alzeghaibi

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Strontium hexaferrite (SrFe12O19; Sr-ferrite) is one of the well-known materials for permanent magnets. In this study, Mtype strontium ferrite was prepared by following the conventional ceramic method from steelmaking by-product. Initial materials; SrCO3 and by-product, were mixed together in the composition of SrFe12O19 in different Sr/Fe ratios. The mixtures of these raw materials were dry-milled for 6h. The blended powder was presintered (i.e. calcination) at 1000°C for different times periods, then cooled down to room temperature. These pre-sintered samples were re-milled in a dry atmosphere for 1h and then fired at different temperatures in atmospheric conditions, and cooled down to room temperature. The produced magnetic powder has a dense hexagonal grain shape structure. The calculated energy product values for the produced samples ranged from 0.3 to 2.4 MGOe.

Keywords: Ceramic route, Hard magnetic materials, Strontium ferrite.

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Authors: Zs. Kovács, Zs. J. Viharos, J. Kodácsy

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As a well-known conventional finishing process, the grinding is commonly used to manufacture seal mating surfaces and bearing surfaces, but is also creates twisted surfaces. The machined surfaces by turning or grinding usually have twist structure on the surfaces, which can convey lubricants such as conveyor screw. To avoid this phenomenon, have to use special techniques or machines, for example start-stop turning, tangential turning, ultrasonic protection or special toll geometries. All of these solutions have high cost and difficult usability. In this paper, we describe a system and summarize the results of the experimental research carried out mainly in the field of Magnetic Abrasive Polishing (MAP) and Magnetic Roller Burnishing (MRB). These technologies are simple and also green while able to produce twist-free surfaces. During the tests, C45 normalized steel was used as workpiece material which was machined by simple and Wiper geometrical turning inserts in a CNC turning lathe. After the turning, the MAP and MRB technologies can be used directly to reduce the twist of surfaces. The evaluation was completed by advanced measuring and IT equipment.

Keywords: Magnetism, finishing, polishing, roller burnishing, twist-free.

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Authors: Masaki Yamaguchi, Akira Ito, Noriaki Okamoto, Yoshinori Kawabe, Masamichi Kamihira

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Heat-inducible gene expression vectors are useful for hyperthermia-induced cancer gene therapy, because the combination of hyperthermia and gene therapy can considerably improve the therapeutic effects. In the present study, we developed an enhanced heat-inducible transgene expression system in which a heat-shock protein (HSP) promoter and tetracycline-responsive transactivator were combined. When the transactivator plasmid containing the tetracycline-responsive transactivator gene was co-transfected with the reporter gene expression plasmid, a high level of heat-induced gene expression was observed compared with that using the HSP promoter without the transactivator. In vitro evaluation of the therapeutic effect using HeLa cells showed that heat-induced therapeutic gene expression caused cell death in a high percentage of these cells, indicating that this strategy is promising for cancer gene therapy.

Keywords: Inducible gene expression, Gene therapy, Hyperthermia, Heat shock protein, Tetracycline transactivator.

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Authors: M. A. Talha, M. Osman Gani, M. Ferdows

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This paper focuses on the study of two dimensional magnetohydrodynamic (MHD) steady incompressible viscous Williamson nanofluid with exponential internal heat generation containing gyrotactic microorganism over a stretching sheet. The governing equations and auxiliary conditions are reduced to a set of non-linear coupled differential equations with the appropriate boundary conditions using similarity transformation. The transformed equations are solved numerically through spectral relaxation method. The influences of various parameters such as Williamson parameter γ, power constant λ, Prandtl number P_r, magnetic field parameter M, Peclet number P_e, Lewis number Le, Bioconvection Lewis number Lb, Brownian motion parameter Nb, thermophoresis parameter Nt, and bioconvection constant σ are studied to obtain the momentum, heat, mass and microorganism distributions. Moment, heat, mass and gyrotactic microorganism profiles are explored through graphs and tables. We computed the heat transfer rate, mass flux rate and the density number of the motile microorganism near the surface. Our numerical results are in better agreement in comparison with existing calculations. The Residual error of our obtained solutions is determined in order to see the convergence rate against iteration. Faster convergence is achieved when internal heat generation is absent. The effect of magnetic parameter M decreases the momentum boundary layer thickness but increases the thermal boundary layer thickness. It is apparent that bioconvection Lewis number and bioconvection parameter has a pronounced effect on microorganism boundary. Increasing brownian motion parameter and Lewis number decreases the thermal boundary layer. Furthermore, magnetic field parameter and thermophoresis parameter has an induced effect on concentration profiles.

Keywords: Convection flow, internal heat generation, similarity, spectral method, numerical analysis, Williamson nanofluid.

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Authors: Musaab Salman Sultan

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The surface and bulk magnetization behavior of template released isolated ferromagnetic Ni₆₀Fe₄₀ nanowires of relatively thick diameters (~200 nm), deposited from a dilute suspension onto pre-patterned insulating chips have been investigated experimentally, using a highly sensitive Magneto-Optical Ker Effect (MOKE) magnetometry and Magneto-Resistance (MR) measurements, respectively. The MR data were consistent with the theoretical predictions of the anisotropic magneto-resistance (AMR) effect. The MR measurements, in all the angles of investigations, showed large features and a series of nonmonotonic "continuous small features" in the resistance profiles. The extracted switching fields from these features and from MOKE loops were compared with each other and with the switching fields reported in the literature that adopted the same analytical techniques on the similar compositions and dimensions of nanowires. A large difference between MOKE and MR measurments was noticed. The disparate between MOKE and MR results is attributed to the variance in the micro-magnetic structure of the surface and the bulk of such ferromagnetic nanowires. This result was ascertained using micro-magnetic simulations on an individual: cylindrical and rectangular cross sections NiFe nanowires, with the same diameter/thickness of the experimental wires, using the Object Oriented Micro-magnetic Framework (OOMMF) package where the simulated loops showed different switching events, indicating that such wires have different magnetic states in the reversal process and the micro-magnetic spin structures during switching behavior was complicated. These results further supported the difference between surface and bulk magnetization behavior in these nanowires. This work suggests that a combination of MOKE and MR measurements is required to fully understand the magnetization behavior of such relatively thick isolated cylindrical ferromagnetic nanowires.

Keywords: MOKE magnetometry, MR measurements, OOMMF package, micro-magnetic simulations, ferromagnetic nanowires, surface magnetic properties.

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Authors: Kaveh Qaderi Bagajan, Osman Khanahmadi, Ziba Mamaghani Chaharborj, Majid Chenaparchi

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The purpose of this study is to investigate the efficacy of the solution-focused brief therapy on improving the psychological wellbeing of family supervisor woman. This study has been carried out by semi-experimental method and in the form of pre-test, post-test performance on two groups (experimental and control), so that one sample group of 30 individuals was randomly achieved and were randomly divided in two groups of experimental (n=15) and control (n=15). To collect data, Ryff scale psychological wellbeing was used. After conducting pre-test (RSPWB) for two experimental and control groups, Solution-focused brief therapy interference was conducted on the experimental group during five two-hour sessions. Finally, Ryff scale psychological wellbeing was reused for the two groups as post-test and achieved outcomes that were analyzed using covariance. The results indicated that the significant increase of average marks of the experimental group in psychological wellbeing had better function than that of the control group. Finally, solution-focused brief therapy for improving psychological well-being of family supervisor women has a suitable capability and could be used in this way.

Keywords: Solution-Focused Brief Therapy, Short-term Therapy, Family Supervisor Women, Psychological Wellbeing.

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Authors: Amal E. Shehata, Manal E. Fareed

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Osteoarthritis (OA) is the most prevalent and far common debilitating form of arthritis which can be defined as a degenerative condition affecting synovial joint. Patients suffering from osteoarthritis often complain of dull ache pain on movement. Physical agents can fight the painful process when correctly indicated and used such as heat or cold therapy Aim. This study was carried out to: Compare the effect of cold, warm and contrast therapy on controlling knee osteoarthritis associated problems. Setting: The study was carried out in orthopedic outpatient clinics of Menoufia University and teaching Hospitals, Egypt. Sample: A convenient sample of 60 adult patients with unilateral knee osteoarthritis. Tools: three tools were utilized to collect the data. Tool I : An interviewing questionnaire. It comprised of three parts covering  sociodemographic data, medical data and adverse effects of the treatment protocol. Tool II : Knee Injury and Osteoarthritis Outcome Score (KOOS) It consists of five main parts. Tool II1 : 0-10 Numeric pain rating scale. Results: reveled that the total knee symptoms score was decreased from moderate symptoms pre intervention to mild symptoms after warm and contrast method of therapy, but the contrast therapy had significant effect in reducing the knee symptoms and pain than the other symptoms. Conclusions: all of the three methods of therapy resulted in improvement in all knee symptoms and pain but the most appropriate protocol of treatment to relive symptoms and pain was contrast therapy.

Keywords: Knee Osteoarthritis, Cold, Warm and Contrast Therapy.

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Authors: Loke Kean Koay, Horizon Gitano-Briggs, Mani Maran Ratnam

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Today air-core coils (ACC) are a viable alternative to ferrite-core coils in a range of applications due to their low induction effect. An analytical study was carried out and the results were used as a guide to understand the relationship between the magnet-coil distance and the resulting attractive magnetic force. Four different ACC models were fabricated for experimental study. The variation in the models included the dimensions, the number of coil turns and the current supply to the coil. Comparison between the analytical and experimental results for all the models shows an average discrepancy of less than 10%. An optimized ACC design was selected for the scanner which can provide maximum magnetic force.

Keywords: Air-Core Coils, Electromagnetic, Linear Optical Scanner

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Authors: Valentina Koliskina

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Change in impedance of an encircling coil is obtained in the present paper for the case where the electric conductivity and magnetic permeability of a metal cylindrical tube depend on the radial coordinate. The system of equations for the vector potential is solved by means of the Fourier cosine transform. The solution is expressed in terms of improper integral containing modified Bessel functions of complex order.

Keywords: Eddy currents, magnetic permeability, Besselfunctions

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Authors: Kai-Long Hsiao

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A conjugate heat transfer for steady two-dimensional mixed convection with magnetic hydrodynamic (MHD) flow of an incompressible quiescent fluid over an unsteady thermal forming stretching sheet has been studied. A parameter, M, which is used to represent the dominance of the magnetic effect has been presented in governing equations. The similar transformation and an implicit finite-difference method have been used to analyze the present problem. The numerical solutions of the flow velocity distributions, temperature profiles, the wall unknown values of f''(0) and '(θ (0) for calculating the heat transfer of the similar boundary-layer flow are carried out as functions of the unsteadiness parameter (S), the Prandtl number (Pr), the space-dependent parameter (A) and temperature-dependent parameter (B) for heat source/sink and the magnetic parameter (M). The effects of these parameters have also discussed. At the results, it will produce greater heat transfer effect with a larger Pr and M, S, A, B will reduce heat transfer effects. At last, conjugate heat transfer for the free convection with a larger G has a good heat transfer effect better than a smaller G=0.

Keywords: Finite-difference method, Conjugate heat transfer, Unsteady Stretching Sheet, MHD, Mixed convection.

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Authors: Hamed Khani Arani, Mohammad Shariyat, Armaghan Mohammadian

Abstract:

In the present study, the free vibration of magnetostrictive nano-plate (MsNP) resting on the Pasternak foundation is investigated. Firstly, the modified couple stress (MCS) and nonlocal elasticity theories are compared together and taken into account to consider the small scale effects; in this paper not only two theories are analyzed but also it improves the MCS theory is more accurate than nonlocal elasticity theory in such problems. A feedback control system is utilized to investigate the effects of a magnetic field. First-order shear deformation theory (FSDT), Hamilton’s principle and energy method are utilized in order to drive the equations of motion and these equations are solved by differential quadrature method (DQM) for simply supported boundary conditions. The MsNP undergoes in-plane forces in x and y directions. In this regard, the dimensionless frequency is plotted to study the effects of small scale parameter, magnetic field, aspect ratio, thickness ratio and compression and tension loads. Results indicate that these parameters play a key role on the natural frequency. According to the above results, MsNP can be used in the communications equipment, smart control vibration of nanostructure especially in sensor and actuators such as wireless linear micro motor and smart nano valves in injectors.

Keywords: Feedback control system, magnetostrictive nano-plate, modified couple stress theory, nonlocal elasticity theory, vibration analysis.

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