Isfahan University of Thechnology
Computational Methods in Engineering
2228-7698
2423-5741
26
2
2008
1
1
Design and Implementation of a High Speed Systolic Serial Multiplier and Squarer for Long Unsigned Integer Using VHDL
1
14
F. Yazdanpanah and A. Vafaei
A systolic serial multiplier for unsigned numbers is presented which operates without zero words inserted between successive data words, outputs the full product and has only one clock cycle latency.
The multiplier is based on a modified serial/parallel scheme with two adjacent multiplier cells. Systolic concept is a well-known means of intensive computational task through replication of functional units and their repetitive use. Digital signal processing applications often involve high-speed sequential data. Bit-serial processing in particular can result in efficient communications, both within and between VLSI chips because of the reduced number of interconnections required. Serial input multipliers have received considerable attention, particularly for hardwired VLSI algorithms used in signal processing application, due to their minimal chip area required for interconnections. Bit-serial architectures are often used in parallel systems with high connectivity to reduce the wiring down to a reasonable level. The conventional add-shift technique for multiplication, which uses a minimum number of gates, is inexpensive to implement, but too slow to achieve the desired result. Iterative array multipliers are needed to satisfy the high speed requirement of systems. With the advantage of high scale integration, the hardware is not regarded as a major obstacle in implementation.
: Systolic arrays, Serial multiplier, Systolic multiplier, FPGA and HDL.
http://jcme.iut.ac.ir/article-1-431-en.html
http://jcme.iut.ac.ir/article-1-431-en.pdf
Isfahan University of Thechnology
Computational Methods in Engineering
2228-7698
2423-5741
26
2
2008
1
1
Stress Fields and Electric Potential in Piezoelectric Cylinders
1
16
A. Ghorbanpour
S. Golabi
and M. Sotoudeh
Smart materials, Piezoelectric cylinder, Radial stress, Hoop stress, Electric potential.
http://jcme.iut.ac.ir/article-1-426-en.html
http://jcme.iut.ac.ir/article-1-426-en.pdf
Isfahan University of Thechnology
Computational Methods in Engineering
2228-7698
2423-5741
26
2
2008
1
1
Evaluating Weld Magnification Factor in Welded Tubular Joints Using Artifitial Neural Networks
15
29
A. Fathi
A. A. Aghakuchak
and Gh. A. Montazer
In welded tubular joints, when the fatigue crack depth is less than 20% of chord wall thickness, the crack growing process is highly affected by weld geometry.
Hence, T-butt solution and weld magnification factor (Mk) are applicable tools for evaluating the crack growth rate in this domain. In this research, the capability of Artificial Neural Network (ANN) for estimating the Mk of weld toe cracks in T-butt joints is investigated. Four Multi-Layer Perceptron (MLP) networks are designed and trained to predict the Mk in deepest point and ends of weld toe cracks under membrane and bending stresses. Training and testing data of networks are extracted from a reputable resource on finite element modeling. Comparison of the results obtained and those from the most recently published equations shows that using ANN seems to be very beneficial in this field
Tubular joint, Offshore platforms, Fatigue crack, Linear elastic fracture mechanics, Weld magnification factor, Artificial Neural Networks
http://jcme.iut.ac.ir/article-1-432-en.html
http://jcme.iut.ac.ir/article-1-432-en.pdf
Isfahan University of Thechnology
Computational Methods in Engineering
2228-7698
2423-5741
26
2
2008
1
1
Investigation of Inclined Retaining Walls (Located on Slopes) Performance against Static and Earthquake Loads
17
31
A. Eslami
H. Modaraei
and H. Ahmadi
Instability of slopes, Vertical & inclined retaining walls, Static earth pressure, Earthquake, Stabiliy control
http://jcme.iut.ac.ir/article-1-427-en.html
http://jcme.iut.ac.ir/article-1-427-en.pdf
Isfahan University of Thechnology
Computational Methods in Engineering
2228-7698
2423-5741
26
2
2008
1
1
A Comparison between Kubelka-Munk and Geometric Models for Prediction of Reflectance Factor of Transparent Fibers
31
45
S. Amiri and S. H. Amirshahi
The reflectance factors of transparent fibers, free delustering agent, are predicted by geometric as well as Kubelka-Munk models.
Transparent fibers are simulated by a net of glass capillary tubes containing different solutions of dyestuffs. Based on the results, prediction of the reflectance factor of capillary net by geometric model is relatively better than those obtained from Kubelka-Munk model. However, the geometric model suffers from a complex and massive computation process. Generally speaking, the geometric model performs better for dark transparent samples due to the ignorable internal scattering phenomena. On the other hand, the Kubelka-Munk model provides better results for light samples, where the geometric model fails in acceptable prediction.
Geometric Model, Kubelka-Munk Theory, Spectral Refelctance, Fibers
http://jcme.iut.ac.ir/article-1-433-en.html
http://jcme.iut.ac.ir/article-1-433-en.pdf
Isfahan University of Thechnology
Computational Methods in Engineering
2228-7698
2423-5741
26
2
2008
1
1
Influence of (SBR) Latex and Silica Fume on Properties and Performance of Cement - based Repair Concretes
33
47
A.R. Bagheri and S. Hashemi
Repair concrete, Bonding strength, Elastic modulus, Unrestrained shrinkage.
http://jcme.iut.ac.ir/article-1-428-en.html
http://jcme.iut.ac.ir/article-1-428-en.pdf
Isfahan University of Thechnology
Computational Methods in Engineering
2228-7698
2423-5741
26
2
2008
1
1
Batch Scheduling in Flexible Flow Shop
41
52
M.R. Amin Naseri
I. Nakhaee
and M. A. Beheshti Nia
In this paper, the problem of batch scheduling in a flexible flow shop environment is studied. It is assumed that machines in some stages are able to process a number of jobs simultaneously. The applications of this problem can be found in various industries including spring and wire manufacturing and in auto industry. A mixed integer programming formulation of the problem is presented and it is shown that the problem is NP-Hard. Three heuristics will then be developed to solve the problem and a lower bound is also developed for evaluating the performance of the proposed heuristics. Results show that heuristic H3 gives better results compared to the others.
Scheduling, Flexible flow shop, Sequencing, Batch, Heuristics.
http://jcme.iut.ac.ir/article-1-434-en.html
http://jcme.iut.ac.ir/article-1-434-en.pdf
Isfahan University of Thechnology
Computational Methods in Engineering
2228-7698
2423-5741
26
2
2008
1
1
Investigation of the Behavior of Rubberized Concrete under Uniaxial Compressive Test
49
58
M. Dehestani
Ali R. Khaloo
and P. Rahmatabadi
Rubber concrete, Mechanical behavior, Stress-strain, Environment
http://jcme.iut.ac.ir/article-1-429-en.html
http://jcme.iut.ac.ir/article-1-429-en.pdf
Isfahan University of Thechnology
Computational Methods in Engineering
2228-7698
2423-5741
26
2
2008
1
1
Radar Signal Detection in K-distributed Clutter by Pade Approximation
53
65
M. Ghaffari
M.R. Taban
M.M. Nayebi
and G. Mirjalily
In this paper, two suboptimum detectors are proposed for coherent radar signal detection in K-distributed clutter. Assuming certain values for several initial moments of clutter amplitude, the characteristic function of the clutter amplitude is approximated by a limited series. Using the Pade approximation, it is then converted to a rational fraction. Thus, the pdf of the clutter amplitude is obtained as a sum of simple exponential functions. Using such a pdf, we develop the suboptimum detectors PGLR and PAALR, which are simplified forms of the GLR and AALR. Computer simulations show that the suggested detectors have appropriate performance compared to OLD, GLR and AALR detectors.
Radar, Detection, Suboptimum, Coherent, Non-Gaussian, K-distributed, Pade approximation
http://jcme.iut.ac.ir/article-1-435-en.html
http://jcme.iut.ac.ir/article-1-435-en.pdf
Isfahan University of Thechnology
Computational Methods in Engineering
2228-7698
2423-5741
26
2
2008
1
1
Formation Mechanism and Enthalpy of Mixing of Nanocrystalline NiTi Intermetallic during Mechanical Alloying
59
70
T. Mousavi
M. H. Abbasi
F. Karimzadeh
and M. H. Enayati
NiTi intermetallic, Nanocrystalline, Mechanical alloying, Enthalpy, Supersaturated solid solution
http://jcme.iut.ac.ir/article-1-430-en.html
http://jcme.iut.ac.ir/article-1-430-en.pdf
Isfahan University of Thechnology
Computational Methods in Engineering
2228-7698
2423-5741
26
2
2008
1
1
Using a Fuzzy Auto Regressive Integrated Moving Average Model for Exchange Rate Forecasting
67
75
Mehdi Khashei and Mehdi Bijari
Forecasting models have wide applications in decision making. In the real world, rapid changes normally take place in different areas, specifically in financial markets. Collecting the required data is a main problem for forecasters in such unstable environments. Forecasting methods such as Auto Regressive Integrated Moving Average (ARIMA) models and also Artificial Neural Networks (ANNs) need large amounts of historical data. Although fuzzy forecasting models such as fuzzy regression are suitable metods when the data available is scant, their performance is not satisfactory at times. In this paper, a new Fuzzy Auto Regressive Integrated Moving Average (FARIMA) is presented. The proposed model can be run with less data, so it is more suitable than other models for cases where there are limited data available. The results obtained on exchange rate forecasting reveal the efficiency of the proposed model.
Exchange rate, Auto Regressive Integrated Moving Average, Fuzzy regression, Time series forecasting, Combined forecast.
http://jcme.iut.ac.ir/article-1-436-en.html
http://jcme.iut.ac.ir/article-1-436-en.pdf
Isfahan University of Thechnology
Computational Methods in Engineering
2228-7698
2423-5741
26
2
2008
1
1
Bending-Unbending Analysis of Anisotropic Sheet under Plane Strain Condition
77
86
M. Salimi
M. Jamshidian
A. Beheshti
and A. Sadeghi Dolatabadi
The mechanical behavior of cold rolled sheets is significantly related to residual stresses that arise from bending and unbending processes. Measurement of residual stresses is mostly limited to surface measurement techniques. Experimental determination of stress variation through thickness is difficult and time-consuming. This paper presents a closed form solution for residual stresses, in which the bending-unbending process is modeled as an elastic-plastic plane strain problem. An anisotropic material is assumed. To validate the analytical solution, finite element simulation is also demonstrated. This study is applicable to analysis of coiling-uncoiling, leveling and straightening processes.
Residual stresses, Elastic-plastic Bending-unbending, Anisotropy, Finite element method.
http://jcme.iut.ac.ir/article-1-437-en.html
http://jcme.iut.ac.ir/article-1-437-en.pdf