Bahram Jozi

University of Technology Sydney, Faculty of Engineering and IT, Graduate Student

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Supervisors: Prof. Robin Braun, Prof. Bijan Samali, and Prof. Jianchun Li

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Papers by Bahram Jozi

Condition assessment of in-service timber utility poles utilizing advanced digital signal processing and multi-sensors array

format_quoteCurrent surface stress wave NDT methods are ineffective for assessing timber poles; wave complexity complicates evaluations significantly.format_quote

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Field efficacy of natural and conventional insecticides against lucerne aphids and their impact on predators

Journal of the Maharashtra Agricultural Universities, 2005

Harmonic opponent modeling and behavior structure for 3D soccer simulation agent

2009 IEEE International Symposium on Computational Intelligence in Robotics and Automation - (CIRA), 2009

Abstract-- As the beginning of the 3D soccer simulation competitions the simulated humanoid robot... more

Implementation of an airborne P-band ice sounding radar

… (EUSAR), 2008 7th …, 2008

... Anders Kusk, National Space Institute, Technical University of Denmark Jan Balling, National ... more

An intelligent fuzzy controller based on genetic algorithms

2009 IEEE International Symposium on Computational Intelligence in Robotics and Automation - (CIRA), 2009

In view of many applications, in recent years, there has been increasing interest in robot's cont... more In view of many applications, in recent years, there has been increasing interest in robot's control. Two intelligent controllers based on fuzzy logic and neural network are developed to trace the desired trajectory for a robot. A variety of evolutionary algorithms, have been proposed to approximately solve problems of common engineering applications. Increasingly common applications involve automatic learning of nonlinear mappings that govern the behavior of control systems. In many cases where robot control is of primary concern, the systems used to demonstrate the effectiveness of evolutionary algorithms often do not represent practical robotic systems. In this paper, genetic algorithms (GA) are the evolutionary strategy of interest. This procedure and the manner in which fuzzy controllers are codified into chromosomes is described. It is applied to learn fuzzy control rules for a practical autonomous vehicle steering control problem, namely, path tracking. GA handles the simultaneous evolution of membership functions and rule bases for the fuzzy path tracker. Simulation results show that the proposed fuzzy controller whose all parameters have been tuned simultaneously using GAs, offers advantages over existing controllers and has improved performance.

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An optimized gait generator based on fourier series towards fast and robust biped locomotion involving arms swing

Abstract- Bipedal locomotion is one of the most challenging problems in control, artificial intel... more Abstract- Bipedal locomotion is one of the most challenging problems in control, artificial intelligence, mechanics and other related fields. In this article a model free approach with emphasis on making robot’s walking more stable and faster is presented. In this regard we use Particle Swarm Optimization (PSO) to optimize the signals produced by Truncated Fourier Series (TFS) which control joints ’ angels. The role of hands is also considered to smooth walking and to increase its robustness. For the first time a new method will be introduced to improve the speed and robustness of bipedal walking by refining signals and reducing the role of inertia. Simulation results show this approach can make the robot's walking more stable and faster than walking without considering the role of hands and inertia effect.

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Investigating O:MIB-based Distributed Active Information Model (DAIM) for Autonomics

Technological innovations in communication networking, computing applications, and information mo... more Technological innovations in communication networking, computing applications, and information modeling have played a significant role in managing complex distributed electronic systems. Autonomic Computing (AC) is a concept to deal with the over growing complexity of distributed networks; this term gives systems the ability of self-management, which mean each component in AC can adapt itself to changing conditions of the dynamic environment. In this paper we investigate a new natureinspired Distributed Active Information Model (DAIM) to allow the local decision making process, that will essentially contribute to complex distributed network environments. Details of the DAIM structure are also described, which will hopefully address the schemes of some previous network management protocols such as Simple Network Management Protocol (SNMP), Common Information Model (CIM), and mechanism like Policy-Based Network Management. Finally, we will introduce a benchmark networking system calle...

format_quoteDAIM employs adaptation algorithms with intelligent agents, enabling autonomous local decision-making in complex distributed networks.format_quote

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Application and improvement of conventional stress-wave-based non-destructive testing methods for the condition assessment of in-service timber utility poles

Timber utility poles represent a significant part of Australia’s infrastructure for power distrib... more Timber utility poles represent a significant part of Australia’s infrastructure for power distribution and communication networks. Due to their advanced age, significant efforts are undertaken to prevent utility lines from failure. However, the lack of reliable tools for assessing the condition of in-service poles seriously jeopardizes the maintenance and asset management. Non-destructive testing (NDT) methods based on stress wave propagation can potentially offer simple and cost-effective tools for the condition assessment of in-service timber poles. Based on the impact direction and location, mainly two wave types can be excited in a pole, i.e. longitudinal and bending waves. A conventional stresswave-based method that analyses longitudinal waves is the Sonic Echo (SE) method; and a typical signal processing method for the analysis of bending waves (BW) is the Short Kernel Method (SKM). In this paper, firstly, the application of the conventional SE method and the BW method with SK...

format_quoteEstimation errors in wave velocity differ based on sensor location, affecting the reliability of condition assessments for timber utility poles.format_quote

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Separation of bi-directional stress waves for the non-destructive condition assessment of in-service timber utility

Timber utility poles represent a significant part of Australia's infrastructure for power distrib... more Timber utility poles represent a significant part of Australia's infrastructure for power distribution and communication networks. Due to the advanced age of Australia's timber pole infrastructure, significant efforts are undertaken by state authorities on maintenance and asset management to prevent utility lines from failure. However, the lack of reliable tools for assessing the condition of in-service poles seriously jeopardizes the maintenance and asset management. For example, each year approximately 300,000 poles are replaced in the Eastern States of Australia with up to 80% of them still being in a very good serviceable condition, resulting in significant waste of natural resources and money. Non-destructive testing (NDT) methods based on stress wave propagation can potentially offer simple and costeffective tools for identifying the in-service condition of timber poles. However, most of the currently available methods are not suitable for condition assessment of timber poles in-service due to complicating factors such as orthotropic material properties, soil embedment, complex wave behaviour and other uncertainties. An additional challenge for the assessment of poles is the simultaneous presence of upward and downward travelling waves resulting from the impact excitation at the lower section of the pole instead of the top due to practical constraints; i.e. in field testing, access to the top section of timber utility poles is prohibitive. The presence of the bi-directional travelling waves with their reflections from two ends of the pole produces complex wave propagation patterns that lead to difficulties in wave interpretation and analysis. This paper attempts to solve this problem by proposing a signal processing method based on low pass Finite Impulse Response (FIR) digital filtering, predictive deconvolution, and frequency wavenumber (F-K) phase velocity filtering algorithms to separate upward and downward travelling waves from the stress wave testing signals, and as a result detect a clear reflection from the bottom of the pole for embedment length estimation. In the proposed technique, first, low pass FIR digital filtering is applied to remove noise and unwanted high frequency components. Then, a predictive deconvolution algorithm is employed for the separation of the bi-directional wave of a pole with isotropic material properties. Finally, and F-K filter is designed and applied for better reflection detection of an orthotropic pole. The method is tested on numerical data of a timber pole modelled with both isotropic and orthotropic material properties.