In this study, the effects of magnetic field and nanoparticle on the Jeffery- Hamel flow are studied using a powerful analytical method called the Adomian decomposition method （ADM）. The traditional Navier-Stokes eq...In this study, the effects of magnetic field and nanoparticle on the Jeffery- Hamel flow are studied using a powerful analytical method called the Adomian decomposition method （ADM）. The traditional Navier-Stokes equation of fluid mechanics and Maxwell＇s electromagnetism governing equations are reduced to nonlinear ordinary differential equations to model the problem. The obtained results are well agreed with that of the Runge-Kutta method. The present plots confirm that the method has high accuracy for different a, Ha, and Re numbers. The flow field inside the divergent channel is studied for various values of Hartmann ：number and angle of channel. The effect of nanoparticle volume fraction in the absence of magnetic field is investigated.展开更多
A simple and highly accurate semi-analytical method, called the differential transformation method(DTM), was used for solving the nonlinear temperature distribution equation in solid and porous longitudinal fin with t...A simple and highly accurate semi-analytical method, called the differential transformation method(DTM), was used for solving the nonlinear temperature distribution equation in solid and porous longitudinal fin with temperature dependent internal heat generation. The problem was solved for two main cases. In the first case, heat generation was assumed variable by fin temperature for a solid fin and in second heat generation varied with temperature for a porous fin. Results are presented for the temperature distribution for a range of values of parameters appearing in the mathematical formulation(e.g. N, εG, and G). Results reveal that DTM is very effective and convenient. Also, it is found that this method can achieve more suitable results in comparison to numerical methods.展开更多
In this paper motion of rigid rod on a circular surface is studied analytically.A new analytical method called modified homotopy perturbation method(MHPM)is applied for solving this problem in different initial condit...In this paper motion of rigid rod on a circular surface is studied analytically.A new analytical method called modified homotopy perturbation method(MHPM)is applied for solving this problem in different initial conditions to show capability of this method.The goveming equation for motion of a nigid rod on the circular surface without slipping have been solved using MHPM.The efficacy of MHPM for handling nonlinear oscillation systems with various small and large oscillation amplitudes are presented in comparison with numerical benchmarks.Outcomes reveal that MHPM has an excellent agreement with numerical solution.The results show that by decreasing the oscillation amplitude,the velocity of rigid rod decreases and for A=w3 the velocity profile is maximum.展开更多
In this paper, first a circular diaphragm is modeled using the classical plate theory. An analytical solution based on differential transformation method （DTM） and Runge-Kutta method is employed for solving the gove...In this paper, first a circular diaphragm is modeled using the classical plate theory. An analytical solution based on differential transformation method （DTM） and Runge-Kutta method is employed for solving the governing differential equation for the first time. Then the influences of various parameters on central deflection of the diaphragm, stress distribution and capacitance of pressure sensor with a time-dependent pressure are examined. Several case studies are compared with simulations to confirm the proposed method. The analytical results compared with ABAQUS simulation show excellent agreement with the simulation results. This method is very promising for time saving in calculating micro-device characteristics.展开更多
In this study, coupled equations of the motion of a particle in a fluid forced vortex were investigated using the differential transformation method （DTM） with the Pad6 approximation and the differential quadrature ...In this study, coupled equations of the motion of a particle in a fluid forced vortex were investigated using the differential transformation method （DTM） with the Pad6 approximation and the differential quadrature method （DO_M）. The significant contribution of the work is the introduction of two new, fast and efficient solutions for a spherical particle in a forced vortex that are improvements over the previous numerical results in the literature. These methods represent approximations with a high degree of accuracy and minimal computational effort for studying the particle motion in a fluid forced vortex. In addition, the velocity profiles （angular and radial） and the position trajectory of a particle in a fluid forced vortex are described in the current study.展开更多
Ba0.5Sr0.5Co0.8Fe0.1Ni0.1O3δ（BSCFNiO） perovskite oxides were synthesized using a combined EDTA-citrate complexation method,and then pressed into disk and applied in a membrane reactor.The performance of the BSCFNiO...Ba0.5Sr0.5Co0.8Fe0.1Ni0.1O3δ（BSCFNiO） perovskite oxides were synthesized using a combined EDTA-citrate complexation method,and then pressed into disk and applied in a membrane reactor.The performance of the BSCFNiO membrane reactor was studied for partial oxidation of methane over Ni/α-Al 2 O 3 catalyst.The time dependence of oxygen permeation rate and catalytic performance of BSCFNiO membrane during the catalyst initiation stage were investigated at 850 C.In unsteady state,oxygen permeation rate,methane conversion and CO selectivity were closely related to the state of the catalyst.After 300 min from the initial time,the reaction condition reached to steady state and oxygen permeation rate were obtained about 11.7cm 3 cm 2 min 1.Also,the performance of membrane reactor was studied at the temperatures between 750 and 950 C.The results demonstrated good performance for the membrane reactor,as CH 4 conversion and CO selectivity permeation rate reached 98% and 97.5%,respectively,and oxygen permeation rate was about 14.5 cm 3 cm 2 min 1 which was 6.8 times higher than that of air-helium gradient.Characterization of membrane surface by SEM after reaction showed that the original grains disappeared on both surfaces exposed to the air and reaction side,but XRD profile of the polished surface membrane indicated that the membrane bulk preserved the perovskite structure.展开更多
The demand for green-power-driven flexible energy storage systems is increasing.This requires new materials for power-ing wearable electronic devices without conceding energy and power densities.Herein,a nanograss-flo...The demand for green-power-driven flexible energy storage systems is increasing.This requires new materials for power-ing wearable electronic devices without conceding energy and power densities.Herein,a nanograss-flower-like nickel di-vanadium selenide(NiV_(2)Se_(4))is fabricated on a flexible Ni–Cu–Co fabric by a scalable oil bath deposition approach.The NiV_(2)Se_(4)is decorated with silver(Ag)nanoparticles(NiV_(2)Se_(4)–Ag)to improve the electrical conductivity of the electrode surface.The NiV_(2)Se_(4)–Ag electrode exhibits a 27%higher capacity than the NiV_(2)Se_(4)electrode at 1 mA cm^(-2),owing to the synergistic effect of Ag nanoparticles and NiV_(2)Se_(4).Aqueous and flexible hybrid supercapacitors(HSCs)are fabricated with NiV_(2)Se_(4)–Ag and activated carbon(AC)electrodes(NiV_(2)Se_(4)–Ag//AC),which work up to 1.6 V.Aqueous NiV_(2)Se_(4)–Ag//AC HSCs maintain 76%capacitance at a current density of 10 mA cm^(-2)and deliver an energy density of 77 Wh kg^(-1)at a power density of 749 W kg^(-1).Moreover,these HSCs exhibit an excellent cycling stability of 95%after 10,000 galvanostatic charge–discharge cycles.Ultimately,this study demonstrates the potential of NiV_(2)Se_(4)–Ag//AC flexible HSCs for wearable electronics.These HSCs can withstand different bending and twisting angles without compromising the electrochemical performance.The fabricated flexible HSCs can also be recharged by sunlight,providing a sustainable way to utilize natural energy resources.展开更多
This work focuses on transient thermal behavior of radial fins of rectangular,triangular and hyperbolic profiles with temperature-dependent properties.A hybrid numerical algorithm which combines differential transform...This work focuses on transient thermal behavior of radial fins of rectangular,triangular and hyperbolic profiles with temperature-dependent properties.A hybrid numerical algorithm which combines differential transformation(DTM) and finite difference(FDM) methods is utilized to theoretically study the present problem.DTM and FDM are applied to the time and space domains of the problem,respectively.The accuracy of this method solution is checked against the numerical solution.Then,the effects of some applicable parameters were studied comparatively.Since a broad range of governing parameters are investigated,the results could be useful in a number of industrial and engineering applications.展开更多
Perovskite-type a0.5Sr0.5Co0.8Fe0.1R0.1O3-δ （R=Al, Mn, Fe, Ce, Cr, Ni, Co） oxide membranes were ex- ploited and synthesized. Oxygen behavior, order-disorder transition and phase stability of these composite oxides ...Perovskite-type a0.5Sr0.5Co0.8Fe0.1R0.1O3-δ （R=Al, Mn, Fe, Ce, Cr, Ni, Co） oxide membranes were ex- ploited and synthesized. Oxygen behavior, order-disorder transition and phase stability of these composite oxides were investigated by combined analysis of X-ray diffraction （XRD）, temperature programmed desorp- tion （TPD）, thermogravimetric-differential thermal analysis （TG-DTA）. Oxygen permeation through these membranes was studied by the gas chromatography （GC） method using a high-temperature permeation cell in a wide temperature range from 700 to 950℃. High permeation fluxes were observed for these materials. The high permeation flux was about 3.19 ml.min-l.cm-2 under air/He gradients at 950℃, which was achieved for a0.5Sr0.5Co0.8Fe0.1R0.1O3-δ（BSCFNiO） membrane. The results of analysis showed no phase transition for BSCFNiO oxide with increasing temperature and XRD pattern of this material after O2-TPD indicated to sustain a pure perovskite structure after oxygen permeation process.展开更多
This paper describes analytical and numerical methods to analyze the steady state periodic response of an oscillator with symmetric elastic and inertia nonlinearity. A new implementation of the homotopy perturbation m...This paper describes analytical and numerical methods to analyze the steady state periodic response of an oscillator with symmetric elastic and inertia nonlinearity. A new implementation of the homotopy perturbation method （HPM） and an ancient Chinese method called the max-rain approach are presented to obtain an approximate solution. The major concern is to assess the accuracy of these approximate methods in predicting the system response within a certain range of system parameters by examining their ability to establish an actual （numerical） solution. Therefore, the analytical results are compared with the numerical results to illustrate the effectiveness and convenience of the proposed methods.展开更多
Objective： The high burden of injuries in Iran necessitates the establishment of a comprehensive trauma care system. The purpose of this paper is to describe the current status of trauma system regarding the componen...Objective： The high burden of injuries in Iran necessitates the establishment of a comprehensive trauma care system. The purpose of this paper is to describe the current status of trauma system regarding the components and function. Methods： The current status of trauma system in all components of a trauma system was described through expert panels and semi-structured interviews with trauma specialists and policy makers. Results： Currently, various organizations are involved in prevention, management and rehabilitation of injuries, but an integrative system approach to trauma is rather deficient. There has been ongoing progress in areas of public education through media, traffic regulation reinforcement, hospital care and prehospital services. Meanwhile, there are gaps regarding financing, legislations and education of high risk groups. The issues on education and training standards of the front line medical team and continuing education and evaluation are yet to be addressed. Trauma registry has been piloted in some provinces, but as it needs the well-developed infrastructure （regarding staff, maintenance, financial resources）, it is not yet established in our system of trauma care. Conclusions： It seems that one of the problems with trauma care in Iran is lack of coordination among trauma system organizations. Although the clinical management of trauma patients has improved in our country in the recent decade, decreasing the burden of injuries necessitates an organized approach to prevention and management of trauma in the context of a trauma system.展开更多
In the present paper, three complicated non- linear differential equations in the field of vibration, which are Vanderpol, Rayleigh and Duffing equations, have been analyzed and solved completely by Algebraic Method ...In the present paper, three complicated non- linear differential equations in the field of vibration, which are Vanderpol, Rayleigh and Duffing equations, have been analyzed and solved completely by Algebraic Method （AGM）. Investigating this kind of equations is a very hard task to do and the obtained solution is not accurate and reliable. This issue will be emerged after comparing the achieved solutions by numerical method （Runge-Kutte 4th）. Based on the comparisons which have been made between the gained solutions by AGM and numerical method, it is possible to indicate that AGM can be successfully applied for various differential equations particularly for difficult ones. The results reveal that this method is not only very effective and simple, but also reliable, and can be applied for other complicated nonlinear problems.展开更多
AIM: To assess the distribution of human leukocyte antigen (HLA)-DQ2 and -DQ8 in Iranian celiac disease (CD) patients and compare them to healthy Iranian controls.
Magnetic nanofiuid hydrothermal analysis over a plate is studied that includes consideration of thermal radiation. The Runge-Kutta （RK4） method is utilized to get solution of ODEs which are obtained from similarity ...Magnetic nanofiuid hydrothermal analysis over a plate is studied that includes consideration of thermal radiation. The Runge-Kutta （RK4） method is utilized to get solution of ODEs which are obtained from similarity solution. In considering the impacts of Brownian motion, we applied Koo-Kleinstreuer-Li cor- relation to simulate the properties of CuO-water. The influence is discussed of important parameters such as the temperature index, magnetic, radiation, and velocity ratio parameters and volume fraction of nanoparticle on hydrothermal behavior. Results illustrate that the coefficient of skin friction enhances with enhancing magnetic parameter while reduces with enhancing velocity ratio parameter. Also the Nusselt number was found to directly depend on the velocity ratio and temperature index parameters but has an inverse dependence on the magnetic and radiation parameters.展开更多
<strong>Introduction:</strong> Unilateral nasal mass can be benign or malignant. Very rarely we will find benign salivary gland tumor in nasal cavity. Pleomorphic adenoma is still the most common pathologi...<strong>Introduction:</strong> Unilateral nasal mass can be benign or malignant. Very rarely we will find benign salivary gland tumor in nasal cavity. Pleomorphic adenoma is still the most common pathological variety either in major or minor salivary gland tumors. In the nasal cavity, even though most of the accessory salivary glands are present in the lateral wall of nose, nasal septum remains the most common site of origin. <strong>Case Report:</strong> A 40-year-old female presented with right-sided nasal obstruction and epistaxis. CT scan of Nose and Paranasal sinuses found a lesion involving the anterior third of the right nasal cavity. The patient underwent complete surgical resection of the tumor via an endonasal approach. Histological examination found a mixed cellular component (epithelial and myoepithelial) and mesenchymatous tissue with chondromyxoid stroma, enabling diagnosis of a typical pleomorphic adenoma. <strong>Conclusion:</strong> Pleomorphic adenoma is the most common salivary gland tumor but rare to find in the nasal cavity with only few cases reported in the literature. Although benign, the risk of local recurrence, malignant transformation and metastasis requires close long-term follow-up.展开更多
<strong>Introduction:</strong> Rhabdomyosarcoma accounts for up to 60% of childhood soft tissue sarcoma, occurring mostly in the head and neck region but rarely in the ear and temporal areas. <strong>...<strong>Introduction:</strong> Rhabdomyosarcoma accounts for up to 60% of childhood soft tissue sarcoma, occurring mostly in the head and neck region but rarely in the ear and temporal areas. <strong>Case Report:</strong> A 4-year-old boy came to our hospital due to a purulent discharge, bleeding from his left ear. Also seen mass in the left ear along with facial weakness and diplopia. After histopathologic evaluation, it was diagnosed as embryonal rhabdomyosarcoma. <strong>Conclusion:</strong> Rhabdomyosarcoma should be kept in mind as a differential diagnosis in all children presenting with otitis media with mastoiditis. Biopsy should be considered who are not responding to medications and those worsening condition.展开更多
In this paper,in order to improve the performance of a linear parabolic collector,the thermal effects of using Al_(2)O_(3)-syltherm oil nanofluid with different concentrations and new flange-shaped turbulators are inv...In this paper,in order to improve the performance of a linear parabolic collector,the thermal effects of using Al_(2)O_(3)-syltherm oil nanofluid with different concentrations and new flange-shaped turbulators are investigated.The simulation was performed by ANSYS-FLUENT-18.2 commercial software using Realizable k-εtwo-equation turbulence model.In accordance with the results,it was realized that increasing the volume fraction of nanoparticles(to 5%)and number of turbulators causes the heat transfer coefficient(h)of the fluid to elevate and ultimately the uniform temperature is created in the absorber.For instance,at a flow rate of 4.5kg/s and an inlet temperature of 350 K,the value of h increases by about 8.5%by changing the number of turbulators from 10 to 15 sets.On the other hand,the results indicate that by changing the arrangement of the turbulators,the heat transfer efficiency of the collector can be increased by 5%for 350 K,3.5%for 450 K and 1%for 550 K inlet temperature.展开更多
In the current paper, a simplified model of Tower Cranes has been presented in order to investigate and analyze the nonlinear differential equation governing on the presented system in three different cases by Algebra...In the current paper, a simplified model of Tower Cranes has been presented in order to investigate and analyze the nonlinear differential equation governing on the presented system in three different cases by Algebraic Method （AGM）. Comparisons have been made between AGM and Numerical Solution, and these results have been indicated that this approach is very efficient and easy so it can be applied for other nonlinear equations. It is citable that there are some valuable advantages in this way of solving differential equations and also the answer of various sets of complicated differential equations can be achieved in this manner which in the other methods, so far, they have not had acceptable solutions. The simplification of the solution procedure in Algebraic Method and its application for solving a wide variety of differential equations not only in Vibrations but also in different fields of study such as fluid mechanics, chemical engineering, etc. make AGM be a powerful and useful role model for researchers in order to solve complicated nonlinear differential equations.展开更多
文摘In this study, the effects of magnetic field and nanoparticle on the Jeffery- Hamel flow are studied using a powerful analytical method called the Adomian decomposition method （ADM）. The traditional Navier-Stokes equation of fluid mechanics and Maxwell＇s electromagnetism governing equations are reduced to nonlinear ordinary differential equations to model the problem. The obtained results are well agreed with that of the Runge-Kutta method. The present plots confirm that the method has high accuracy for different a, Ha, and Re numbers. The flow field inside the divergent channel is studied for various values of Hartmann ：number and angle of channel. The effect of nanoparticle volume fraction in the absence of magnetic field is investigated.
文摘A simple and highly accurate semi-analytical method, called the differential transformation method(DTM), was used for solving the nonlinear temperature distribution equation in solid and porous longitudinal fin with temperature dependent internal heat generation. The problem was solved for two main cases. In the first case, heat generation was assumed variable by fin temperature for a solid fin and in second heat generation varied with temperature for a porous fin. Results are presented for the temperature distribution for a range of values of parameters appearing in the mathematical formulation(e.g. N, εG, and G). Results reveal that DTM is very effective and convenient. Also, it is found that this method can achieve more suitable results in comparison to numerical methods.
文摘In this paper motion of rigid rod on a circular surface is studied analytically.A new analytical method called modified homotopy perturbation method(MHPM)is applied for solving this problem in different initial conditions to show capability of this method.The goveming equation for motion of a nigid rod on the circular surface without slipping have been solved using MHPM.The efficacy of MHPM for handling nonlinear oscillation systems with various small and large oscillation amplitudes are presented in comparison with numerical benchmarks.Outcomes reveal that MHPM has an excellent agreement with numerical solution.The results show that by decreasing the oscillation amplitude,the velocity of rigid rod decreases and for A=w3 the velocity profile is maximum.
文摘In this paper, first a circular diaphragm is modeled using the classical plate theory. An analytical solution based on differential transformation method （DTM） and Runge-Kutta method is employed for solving the governing differential equation for the first time. Then the influences of various parameters on central deflection of the diaphragm, stress distribution and capacitance of pressure sensor with a time-dependent pressure are examined. Several case studies are compared with simulations to confirm the proposed method. The analytical results compared with ABAQUS simulation show excellent agreement with the simulation results. This method is very promising for time saving in calculating micro-device characteristics.
文摘In this study, coupled equations of the motion of a particle in a fluid forced vortex were investigated using the differential transformation method （DTM） with the Pad6 approximation and the differential quadrature method （DO_M）. The significant contribution of the work is the introduction of two new, fast and efficient solutions for a spherical particle in a forced vortex that are improvements over the previous numerical results in the literature. These methods represent approximations with a high degree of accuracy and minimal computational effort for studying the particle motion in a fluid forced vortex. In addition, the velocity profiles （angular and radial） and the position trajectory of a particle in a fluid forced vortex are described in the current study.
文摘Ba0.5Sr0.5Co0.8Fe0.1Ni0.1O3δ（BSCFNiO） perovskite oxides were synthesized using a combined EDTA-citrate complexation method,and then pressed into disk and applied in a membrane reactor.The performance of the BSCFNiO membrane reactor was studied for partial oxidation of methane over Ni/α-Al 2 O 3 catalyst.The time dependence of oxygen permeation rate and catalytic performance of BSCFNiO membrane during the catalyst initiation stage were investigated at 850 C.In unsteady state,oxygen permeation rate,methane conversion and CO selectivity were closely related to the state of the catalyst.After 300 min from the initial time,the reaction condition reached to steady state and oxygen permeation rate were obtained about 11.7cm 3 cm 2 min 1.Also,the performance of membrane reactor was studied at the temperatures between 750 and 950 C.The results demonstrated good performance for the membrane reactor,as CH 4 conversion and CO selectivity permeation rate reached 98% and 97.5%,respectively,and oxygen permeation rate was about 14.5 cm 3 cm 2 min 1 which was 6.8 times higher than that of air-helium gradient.Characterization of membrane surface by SEM after reaction showed that the original grains disappeared on both surfaces exposed to the air and reaction side,but XRD profile of the polished surface membrane indicated that the membrane bulk preserved the perovskite structure.
基金supported by the National Research Foundation of Korea(NRF)Grant funded by the Korea government(MSIT)(2022M3J7A1062940 and 2022R1A2C2008968)supported by the Korea Environment Industry&Technology Institute(KEITI)through a project to develop Aquatic Ecosystem Conservation Research Program,funded by the Korea Ministry of Environment(MOE)(2022003040004).
文摘The demand for green-power-driven flexible energy storage systems is increasing.This requires new materials for power-ing wearable electronic devices without conceding energy and power densities.Herein,a nanograss-flower-like nickel di-vanadium selenide(NiV_(2)Se_(4))is fabricated on a flexible Ni–Cu–Co fabric by a scalable oil bath deposition approach.The NiV_(2)Se_(4)is decorated with silver(Ag)nanoparticles(NiV_(2)Se_(4)–Ag)to improve the electrical conductivity of the electrode surface.The NiV_(2)Se_(4)–Ag electrode exhibits a 27%higher capacity than the NiV_(2)Se_(4)electrode at 1 mA cm^(-2),owing to the synergistic effect of Ag nanoparticles and NiV_(2)Se_(4).Aqueous and flexible hybrid supercapacitors(HSCs)are fabricated with NiV_(2)Se_(4)–Ag and activated carbon(AC)electrodes(NiV_(2)Se_(4)–Ag//AC),which work up to 1.6 V.Aqueous NiV_(2)Se_(4)–Ag//AC HSCs maintain 76%capacitance at a current density of 10 mA cm^(-2)and deliver an energy density of 77 Wh kg^(-1)at a power density of 749 W kg^(-1).Moreover,these HSCs exhibit an excellent cycling stability of 95%after 10,000 galvanostatic charge–discharge cycles.Ultimately,this study demonstrates the potential of NiV_(2)Se_(4)–Ag//AC flexible HSCs for wearable electronics.These HSCs can withstand different bending and twisting angles without compromising the electrochemical performance.The fabricated flexible HSCs can also be recharged by sunlight,providing a sustainable way to utilize natural energy resources.
文摘This work focuses on transient thermal behavior of radial fins of rectangular,triangular and hyperbolic profiles with temperature-dependent properties.A hybrid numerical algorithm which combines differential transformation(DTM) and finite difference(FDM) methods is utilized to theoretically study the present problem.DTM and FDM are applied to the time and space domains of the problem,respectively.The accuracy of this method solution is checked against the numerical solution.Then,the effects of some applicable parameters were studied comparatively.Since a broad range of governing parameters are investigated,the results could be useful in a number of industrial and engineering applications.
文摘Perovskite-type a0.5Sr0.5Co0.8Fe0.1R0.1O3-δ （R=Al, Mn, Fe, Ce, Cr, Ni, Co） oxide membranes were ex- ploited and synthesized. Oxygen behavior, order-disorder transition and phase stability of these composite oxides were investigated by combined analysis of X-ray diffraction （XRD）, temperature programmed desorp- tion （TPD）, thermogravimetric-differential thermal analysis （TG-DTA）. Oxygen permeation through these membranes was studied by the gas chromatography （GC） method using a high-temperature permeation cell in a wide temperature range from 700 to 950℃. High permeation fluxes were observed for these materials. The high permeation flux was about 3.19 ml.min-l.cm-2 under air/He gradients at 950℃, which was achieved for a0.5Sr0.5Co0.8Fe0.1R0.1O3-δ（BSCFNiO） membrane. The results of analysis showed no phase transition for BSCFNiO oxide with increasing temperature and XRD pattern of this material after O2-TPD indicated to sustain a pure perovskite structure after oxygen permeation process.
文摘This paper describes analytical and numerical methods to analyze the steady state periodic response of an oscillator with symmetric elastic and inertia nonlinearity. A new implementation of the homotopy perturbation method （HPM） and an ancient Chinese method called the max-rain approach are presented to obtain an approximate solution. The major concern is to assess the accuracy of these approximate methods in predicting the system response within a certain range of system parameters by examining their ability to establish an actual （numerical） solution. Therefore, the analytical results are compared with the numerical results to illustrate the effectiveness and convenience of the proposed methods.
文摘Objective： The high burden of injuries in Iran necessitates the establishment of a comprehensive trauma care system. The purpose of this paper is to describe the current status of trauma system regarding the components and function. Methods： The current status of trauma system in all components of a trauma system was described through expert panels and semi-structured interviews with trauma specialists and policy makers. Results： Currently, various organizations are involved in prevention, management and rehabilitation of injuries, but an integrative system approach to trauma is rather deficient. There has been ongoing progress in areas of public education through media, traffic regulation reinforcement, hospital care and prehospital services. Meanwhile, there are gaps regarding financing, legislations and education of high risk groups. The issues on education and training standards of the front line medical team and continuing education and evaluation are yet to be addressed. Trauma registry has been piloted in some provinces, but as it needs the well-developed infrastructure （regarding staff, maintenance, financial resources）, it is not yet established in our system of trauma care. Conclusions： It seems that one of the problems with trauma care in Iran is lack of coordination among trauma system organizations. Although the clinical management of trauma patients has improved in our country in the recent decade, decreasing the burden of injuries necessitates an organized approach to prevention and management of trauma in the context of a trauma system.
文摘In the present paper, three complicated non- linear differential equations in the field of vibration, which are Vanderpol, Rayleigh and Duffing equations, have been analyzed and solved completely by Algebraic Method （AGM）. Investigating this kind of equations is a very hard task to do and the obtained solution is not accurate and reliable. This issue will be emerged after comparing the achieved solutions by numerical method （Runge-Kutte 4th）. Based on the comparisons which have been made between the gained solutions by AGM and numerical method, it is possible to indicate that AGM can be successfully applied for various differential equations particularly for difficult ones. The results reveal that this method is not only very effective and simple, but also reliable, and can be applied for other complicated nonlinear problems.
文摘AIM: To assess the distribution of human leukocyte antigen (HLA)-DQ2 and -DQ8 in Iranian celiac disease (CD) patients and compare them to healthy Iranian controls.
文摘Magnetic nanofiuid hydrothermal analysis over a plate is studied that includes consideration of thermal radiation. The Runge-Kutta （RK4） method is utilized to get solution of ODEs which are obtained from similarity solution. In considering the impacts of Brownian motion, we applied Koo-Kleinstreuer-Li cor- relation to simulate the properties of CuO-water. The influence is discussed of important parameters such as the temperature index, magnetic, radiation, and velocity ratio parameters and volume fraction of nanoparticle on hydrothermal behavior. Results illustrate that the coefficient of skin friction enhances with enhancing magnetic parameter while reduces with enhancing velocity ratio parameter. Also the Nusselt number was found to directly depend on the velocity ratio and temperature index parameters but has an inverse dependence on the magnetic and radiation parameters.
文摘<strong>Introduction:</strong> Unilateral nasal mass can be benign or malignant. Very rarely we will find benign salivary gland tumor in nasal cavity. Pleomorphic adenoma is still the most common pathological variety either in major or minor salivary gland tumors. In the nasal cavity, even though most of the accessory salivary glands are present in the lateral wall of nose, nasal septum remains the most common site of origin. <strong>Case Report:</strong> A 40-year-old female presented with right-sided nasal obstruction and epistaxis. CT scan of Nose and Paranasal sinuses found a lesion involving the anterior third of the right nasal cavity. The patient underwent complete surgical resection of the tumor via an endonasal approach. Histological examination found a mixed cellular component (epithelial and myoepithelial) and mesenchymatous tissue with chondromyxoid stroma, enabling diagnosis of a typical pleomorphic adenoma. <strong>Conclusion:</strong> Pleomorphic adenoma is the most common salivary gland tumor but rare to find in the nasal cavity with only few cases reported in the literature. Although benign, the risk of local recurrence, malignant transformation and metastasis requires close long-term follow-up.
文摘<strong>Introduction:</strong> Rhabdomyosarcoma accounts for up to 60% of childhood soft tissue sarcoma, occurring mostly in the head and neck region but rarely in the ear and temporal areas. <strong>Case Report:</strong> A 4-year-old boy came to our hospital due to a purulent discharge, bleeding from his left ear. Also seen mass in the left ear along with facial weakness and diplopia. After histopathologic evaluation, it was diagnosed as embryonal rhabdomyosarcoma. <strong>Conclusion:</strong> Rhabdomyosarcoma should be kept in mind as a differential diagnosis in all children presenting with otitis media with mastoiditis. Biopsy should be considered who are not responding to medications and those worsening condition.
文摘In this paper,in order to improve the performance of a linear parabolic collector,the thermal effects of using Al_(2)O_(3)-syltherm oil nanofluid with different concentrations and new flange-shaped turbulators are investigated.The simulation was performed by ANSYS-FLUENT-18.2 commercial software using Realizable k-εtwo-equation turbulence model.In accordance with the results,it was realized that increasing the volume fraction of nanoparticles(to 5%)and number of turbulators causes the heat transfer coefficient(h)of the fluid to elevate and ultimately the uniform temperature is created in the absorber.For instance,at a flow rate of 4.5kg/s and an inlet temperature of 350 K,the value of h increases by about 8.5%by changing the number of turbulators from 10 to 15 sets.On the other hand,the results indicate that by changing the arrangement of the turbulators,the heat transfer efficiency of the collector can be increased by 5%for 350 K,3.5%for 450 K and 1%for 550 K inlet temperature.
文摘In the current paper, a simplified model of Tower Cranes has been presented in order to investigate and analyze the nonlinear differential equation governing on the presented system in three different cases by Algebraic Method （AGM）. Comparisons have been made between AGM and Numerical Solution, and these results have been indicated that this approach is very efficient and easy so it can be applied for other nonlinear equations. It is citable that there are some valuable advantages in this way of solving differential equations and also the answer of various sets of complicated differential equations can be achieved in this manner which in the other methods, so far, they have not had acceptable solutions. The simplification of the solution procedure in Algebraic Method and its application for solving a wide variety of differential equations not only in Vibrations but also in different fields of study such as fluid mechanics, chemical engineering, etc. make AGM be a powerful and useful role model for researchers in order to solve complicated nonlinear differential equations.
