ORIGINAL_ARTICLE
Measurement of Heat Characteristics of a New Incubator with a Chemical Energy Source
A heat transfer model was developed for a new non-electric infant’s transport incubator. The source of heat comprises a super saturated solution of Sodium Acetate and a metal disk (activator) in a plastic container. Estimating the number of the chemical bags required for different ambient temperature was the goal. First the quantity of heat generated by the chemical was appointed through experiments and use of a parameter estimation method. The number of the chemical bags were also estimated through a numerical-experimental method.
https://www.ije.ir/article_71540_e983bb9225e2cf7244b2a8c9a435aa9b.pdf
2004-11-01
319
328
Non
Electric Incubator
Sodium Acetate
Water Solution
parameter estimation
heat transfer
Enclosure
Uncertainty
B.
Farhanieh
bifa@sharif.ir
1
Mechanical Engineering, Sharif University of Technology
AUTHOR
Y.
Khodadadeh
yassamankh@hotmail.com
2
Industrial Engineering, Sharif University of Technology
AUTHOR
A. H.
Kakaee
kakaee_ah@iust.ac.ir
3
Automotive Engineering, Iran University of Science & Technology
AUTHOR
ORIGINAL_ARTICLE
Lattice Gas Automata Simulation of Adsorption Process of Polymer in Porous Media
Lattice gas automata (LGA) model is developed to simulate polymer adsorption process by adding some collision rules. The simulation result of the model is matched with batch experiment and compared with accepted isothermal adsorption equations. They show that the model is viable to perform simulation of the polymer adsorption process. The LGA model is then applied for simulating continuous polymer solution flow through porous media. Some parameters such as concentration, surface area, and porosity are varied to examine their effects. The concentration and porosity parameters are found to affect adsorption rate at the transient period whereas the surface area affects the maximum number of adsorbed polymer molecules. Meanwhile, the polymer adsorption in porous media may decrease its permeability and fluid velocity.
https://www.ije.ir/article_71542_f677380d4e720cb835cfe28ffb186b80.pdf
2004-11-01
329
338
Adsorption
Lattice Gas Automata
Porous media
Mariyamni B.
Awang
k-mariy@utm.my
1
Engineering, Universiti Teknologi Malaysia
AUTHOR
Muhammad
Fathaddin
fathaddin@yahoo.com
2
Petroleum Engineering, Universitas Trisakti
AUTHOR
ORIGINAL_ARTICLE
Analysis and Design of a Simple Surge Tank (RESEARCH NOTE)
In a hydroelectric power plant or in a pumping station in order to avoid sudden large increase of pressure due to instantaneous valve closure sometimes a surge tank is installed. The height of surge tank is designed by the highest possible water level during the operation. The theoretical treatment of oscillation in a surge tank is difficult because of the non-linearity of friction term in the governing differential equation of the system. The present study attempts to find a general solution for the surge oscillation in a simple surge tank in terms of non-dimensional parameters. Equations for the highest and the lowest water level in the tank, which are very important in the design of a surge tank have been found.
https://www.ije.ir/article_71544_cb83ad61e31c6e8145a467137000617b.pdf
2004-11-01
339
345
Surge Tank
pressure
Surge Oscillation
Non
Linear Differential Equation
M.
Azhdari Moghaddam
mazhdary@hamoon.usb.ac.ir
1
Civil Engineering, University of Sistan & Baluchestan
AUTHOR
ORIGINAL_ARTICLE
A Proposed Method to Evaluate Ultimate Resistance of Plate Girders Subjected to Shear and Patch Loading (RESEARCH NOTE)
Experimental investigation of the ultimate resistance of slender, steel-plate girder web panels to combined shear-and-patch loading indicates significant interaction between shear loading and patch loading. However, an existing interaction formula is based on experimental results. Herein, an improved design procedure for slender plate girders subjected to combined shear and patch loading is proposed. A modified formula to evaluate shear resistance of plate girders in presence of patch loading is proposed that shows satisfactory correlation with the available test data and is acceptable for practical purposes.
https://www.ije.ir/article_71547_2dbcd3115628a0fcdd96fa652ab804ff.pdf
2004-11-01
347
356
Plate Girders
Combined Shear and Patch Loading
Modified Shear Resistance
H.
Haji Kazemi
hkazemi@um.ac.ir
1
Civil Eng., Ferdowsi University of Mashhad
AUTHOR
F.
Shahabian
fshahabianm@yahoo.com
2
, Ferdowsi Univ. of Mashhad
AUTHOR
ORIGINAL_ARTICLE
Determination of Principal Permeabilities in Two-Dimensional Fissured Rocks Using Permeability Circle (TECHNICAL NOTE)
Among the many parameters affecting the design of hydraulic structures on fissured rocks are orientation of principal permeability axes and degree of anisotropy of fissured rocks. Geological explorations rarely provide this type of information. If at all the information is available, methods employed are computationally cumbersome and inefficient. A new concept of simple equations and geometrical method termed as Permeability Circle similar to Mohr’s circle of stresses has been developed for determination of principal permeability and their orientation from the known characteristics of two-dimensional fissured rock mass.
https://www.ije.ir/article_71548_5b6f9a32b99f88dc831725029e51d5a3.pdf
2004-11-01
357
362
Secondary Permeability
Principal Permeability
Geological explorations
Degree of Anisotropy
Permeability Circle
D.V.S.
Verma
dvs_verma@rediffmail.com
1
Civil Engineering, National Institute of Technology Kurukhshetra
AUTHOR
Krishna Kumar
Singh
k_k_singh_2000@yahoo.com
2
Civil Engineering, National Institute of Technology Kurukhshetra
AUTHOR
ORIGINAL_ARTICLE
Control of Multivariable Systems Based on Emotional Temporal Difference Learning Controller
One of the most important issues that we face in controlling delayed systems and non-minimum phase systems is to fulfill objective orientations simultaneously and in the best way possible. In this paper proposing a new method, an objective orientation is presented for controlling multi-objective systems. The principles of this method is based an emotional temporal difference learning, and has a neuro-fuzzy structure. The proposal method, regarding the present conditions, the system action in the part and the controlling aims, can control the system in a way that these objectives are attain in the least amount of time and the best way. To clarify the issue and verify the proposed the method, three well known control examples which are hard to handle through classic methods are handled by means of the proposed method.
https://www.ije.ir/article_71550_7cd911c416d22c645878bc8721aa82f6.pdf
2004-11-01
363
376
Temporal Difference Learning
Intelligent Control
Multivariable Systems
Emotional Learning
Neuro
fuzzy control
Agent
C.
Lucas
lucas@ipm.ir
1
Intelligent Systems, Sharif University of Technology
AUTHOR
Mehrdad
Fatourechi
mehrdadf@ece.ubc.ca
2
Electerical Engineering, University of British Columbia
AUTHOR
GholamHassan
Famil Khalili
f.khalili@kiau.ac.ir
3
Literature & Humanities, Islamic Azad University
AUTHOR
Javad
Abdi
jabdi@ece.ut.ac.ir
4
Electerical Engineering, Sharif University of Technology
AUTHOR
Ali
Khaki-Sedigh
sedigh@kntu.ac.ir
5
Electerical Engineering, Khaje Nasir Toosi University of Technology
AUTHOR
ORIGINAL_ARTICLE
Ultra-Widband Distributed Amplifier Using Loss Compensation Technique on Both Input and Output Circuit
In this paper, we analyze a distributed amplifier based on input/output attenuation compensation. The analysis is carried out for a HEMT transistor; and a constant-k section filter is used to calculate the amplifier’s characteristics such as attenuation factor, phase constant and gain. The proposed design approach enables us to examine the tradeoff among the variables, which include the type and the number of devices, and the impedance and cutoff frequency of the lines. Consequently, we arrive at a design which gives the desired frequency response with significant bandwidth enhancement of around 70% with about 10% increase in circuit size. The simulation carried out by Advance Design System (ADS) software. Excellent agreement is shown when the theoretically predicted response of a typical amplifier is compared with the result of the computer-aided analysis (simulation).
https://www.ije.ir/article_71552_e333f5b5708273dcf3d5c3f7a55b09d3.pdf
2004-11-01
377
386
Distributed Amplifier
Hemt
Loss Compensation
Bandwidth Enhancement
Mohamed I.
Elmasry
elmasry@uwaterloo.ca
1
VLSI Research Group, University of Waterloo
AUTHOR
M.
Mohammad Taheri
mtaheri@ut.ac.ir
2
Electerical Engineering, University of Tehran
AUTHOR
ORIGINAL_ARTICLE
Numerical Modeling of Mold Filling and Curing in Non-Isothermal RTM Process (RESEARCH NOTE)
Resin Transfer Molding (RTM) is a composite manufacturing process. A preformed fiber is placed in a closed mold and a viscous resin is injected into the mold. In this paper, a model is developed to predict the flow pattern, extent of reaction and temperature change during filling and curing in a thin rectangular mold. A numerical simulation is presented to predict the free surface and its interactions with heat transfer and cure for flow of a shear-thinning resin through the preformed fiber. Finite difference method with marker and cell procedure has been used for front flow position prediction. To verify the model results, the temperature profiles for preformed fiber have been calculated, and compared with the experimental results of the other researchers. The results showed that, to optimize the better quality of production of composite materials, and also considering the effect of curing on temperature distribution during the process, the heat dispersion term should not be neglected.
https://www.ije.ir/article_71556_b4697bf0524f319225f86347d407c6f7.pdf
2004-11-01
391
400
Resin Transfer Molding (RTM)
Porous media
Composites Processing
Curing
A.
Abbassi
abbassi@aut.ac.ir
1
Mechanical enginnering, Amirkabir
AUTHOR
M.R.
Shahnazari
hasnomail@ije.ir
2
Mechanical Engineering, Amirkabir University of Technology
AUTHOR
ORIGINAL_ARTICLE
Simulation of Ideal External and Internal Flows with Arbitrary Boundaries Using Schwarz Christoffel Transformation
The flow field, velocity and pressure coefficient distribution of some 2-D ideal flows are presented. Conformal mapping is used to simulate two-dimensional ideal flow for a variety of complex internal and external configurations, based on the numerical integration of Schwarz-Christoffel transformation. The advantages of this method are simplicity and high accuracy. The method presented in this paper has been applied to flow problems for which established experimental results are available in the literature. The close agreement between the predictions of simulation program and experimental results shows that the present method is applicable to any 2-D ideal flow regardless of the system of coordinates.
https://www.ije.ir/article_71558_289c88d3ff2565e3b2151faf392e8e9e.pdf
2004-11-01
405
414
Ideal Flow
Conformal mapping
Schwarz
Christoffel Transformation
S.M.
Hosseini Sarvari
hasnomail@ije.ir
1
Mechanical Engineering, University of Sistan & Baluchestan
AUTHOR
M. A.
Mehrabian
ma_mehrabian@yahoo.com
2
Mechanical, Shahid Bahonar University of Kerman
AUTHOR
S. H.
Mansouri
mansouri@alum.mit.edu
3
Mechanical Engineering, Shahid Bahonar University of Kerman
AUTHOR