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Full-Text Articles in Mechanical Engineering

C.V. - Wojciech Budzianowski, Wojciech M. Budzianowski Jan 2017

C.V. - Wojciech Budzianowski, Wojciech M. Budzianowski

Wojciech Budzianowski

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Renewable Energy And Sustainable Development (Resd) Group, Wojciech M. Budzianowski Jan 2017

Renewable Energy And Sustainable Development (Resd) Group, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Procesy Cieplne I Aparaty (Lab), Wojciech M. Budzianowski Jan 2016

Procesy Cieplne I Aparaty (Lab), Wojciech M. Budzianowski

Wojciech Budzianowski

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Nonlinear 3d Finite Element Modeling For Structural Failure Analysis Of Concrete Sleepers/Bearers At An Urban Turnout Diamond, Minh Vu, Sakdirat Kaewunruen, Mario Attard Jan 2016

Nonlinear 3d Finite Element Modeling For Structural Failure Analysis Of Concrete Sleepers/Bearers At An Urban Turnout Diamond, Minh Vu, Sakdirat Kaewunruen, Mario Attard

Sakdirat Kaewunruen

Railway urban turnout is a special track system used to divert a train from a particular direction or a particular track onto other directions or other tracks. It is a structural grillage system that consists of steel rails, points (or called “switches”), crossings, steel plates, rubber pads, insulators, fasteners, screw spikes, beam bearers (either tim- ber, polymer, steel, or concrete), ballast and formation. There are two types of turnouts, a conventional turnout and a tangential turnout. Standard conventional turnouts are designed typically for straight main line track. The combination of switch length, heel angle, and cross rate defines the turnout …


Inżynieria Chemiczna Lab., Wojciech M. Budzianowski Jan 2016

Inżynieria Chemiczna Lab., Wojciech M. Budzianowski

Wojciech Budzianowski

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Rail Squats: Understand Its Causes, Severity, And Non-Destructive Evaluation Techniques, Sakdirat Kaewunruen, Makoto Ishida Jul 2015

Rail Squats: Understand Its Causes, Severity, And Non-Destructive Evaluation Techniques, Sakdirat Kaewunruen, Makoto Ishida

Sakdirat Kaewunruen

Generally, rail squats are defined by the growth of any cracks that have grown longitudinally through the rail subsurface and some of the cracks propagating to the bottom of rails transversely have branched from initial longitudinal cracks with a depression of rail surface. The rail defects are commonly referred to as ‘squats’ when they were initiated from damage caused by rolling contact fatigue, and as ‘studs’ when they were associated with white etching layer caused by the transform from pearlitic steel due to friction heat generated by wheel sliding or excessive traction. Such rail surface defect induces wheel/rail impact and …


Severity And Growth Evaluation Of Rail Corrugations On Sharp Curves Using Wheel/Rail Interaction, Sakdirat Kaewunruen, Steve Marich Jul 2015

Severity And Growth Evaluation Of Rail Corrugations On Sharp Curves Using Wheel/Rail Interaction, Sakdirat Kaewunruen, Steve Marich

Sakdirat Kaewunruen

A railway network generally spans over a large distance so the structural health monitoring of such a rail infrastructure system is one of the critical challenges in rail industry practice. Especially in an underground/subway or elevated system, the facilities, resources and time period permitted for critical infrastructure inspection and maintenance is considerably limited. As a result, the automated inspection system of railway is in very high demand. Rail corrugation defect is the periodic, undulated or wave-like vertical alignment of rail surface. The wavelength and severity of rail corrugations is dependant to track structure, track geometry, traction system, rail vehicle behaviours, …


Design Of Holes And Web Openings In Railway Prestressed Concrete Sleepers, Erosha Kahawatta Gamage, Sakdirat Kaewunruen, Alex M. Remennikov Jun 2015

Design Of Holes And Web Openings In Railway Prestressed Concrete Sleepers, Erosha Kahawatta Gamage, Sakdirat Kaewunruen, Alex M. Remennikov

Sakdirat Kaewunruen

As the crosstie beam in railway track systems, the prestressed concrete sleepers (or railroad ties) are principally designed in order to carry wheel loads from the rails to the ground. Their design takes into account static and dynamic loading conditions. It is evident that prestressed concrete has played a significant role as to maintain the high endurance of the sleepers under low to moderate repeated impact loads. In spite of the most common use of the prestressed concrete sleepers in railway tracks, there have always been many demands from rail engineers to improve serviceability and functionality of concrete sleepers. For …


Finite Element Modelling Of Modular Precast Composites For Railway Track Support Structure – A Battle To Save Sydney Harbour Bridge, Dane Griffin, Olivia Mirza, Kenny Kwok, Sakdirat Kaewunruen Apr 2015

Finite Element Modelling Of Modular Precast Composites For Railway Track Support Structure – A Battle To Save Sydney Harbour Bridge, Dane Griffin, Olivia Mirza, Kenny Kwok, Sakdirat Kaewunruen

Sakdirat Kaewunruen

Railway networks in Australian alone require replacing a large amount of aging timber components in excess of 280,000 m3 per year. The replacement of timber track components is responsible for producing greenhouse gas emissions 6 times greater than equivalent reinforced concrete counterparts. Sydney Harbour Bridge presently experiences similar problem. A feasibility study to develop an innovative solution for the replacement of aging timber transoms installed on the Sydney Harbour Bridge was conducted to evaluate environmental, safety and financial benefits. The development of alternative composite structure to replace the timber components overcomes some potential compatibility issues with track stiffness as well …


Eggshells: A Novel Bio-Filler For Intumescent Flame-Retardant Coatings Apr 2015

Eggshells: A Novel Bio-Filler For Intumescent Flame-Retardant Coatings

Faculty of Engineering University of Malaya

The aim of this study was to develop intumescent flame-retardant coatings that incorporate chicken eggshell (CES) waste as a novel eco-friendly bio-filler. Three flame-retardant additives, namely, ammonium polyphosphate phase II, pentaerythritol and melamine were mixed with flame-retardant fillers and acrylic binder to synthesize the intumescent coatings. The fire performance of the coatings was evaluated in accordance with 'BS 476: Part 6-Fire Propagation' and 'BS 476: Part 7-Surface Spread of Flame' test standards. It was found that 4 out of 5 of the coated specimens (B, C, D and E) neither showed surface spread of flame nor any afterglow combustion upon …


Using Local Stiffness Indicator To Examine The Effect Of Honeycombs On The Flexural Stiffness Of Reinforced Concrete Beams Mar 2015

Using Local Stiffness Indicator To Examine The Effect Of Honeycombs On The Flexural Stiffness Of Reinforced Concrete Beams

Faculty of Engineering University of Malaya

Experimental modal analysis was performed on RC beams with honeycombs. The mode shapes were extracted, and the eigenvectors were used in determining the mode shape equations using nonlinear regression. The equation used in the regression was the generalized solution of transverse vibration of a Bernoulli-Euler prismatic beam. By utilizing the regressed phase variable, the global flexural stiffness was evaluated. It was observed that the global stiffness dropped with increasing volumes of the honeycombs in the beam. The results were compared with values computed using the secant modulus from the load-deflection plot obtained upon loading at each load stage and the …


Soft Computing Methodologies For Estimation Of Bridge Girder Forces With Perforations Under Tsunami Wave Loading Mar 2015

Soft Computing Methodologies For Estimation Of Bridge Girder Forces With Perforations Under Tsunami Wave Loading

Faculty of Engineering University of Malaya

Tsunamis pose a great threat to coastal infrastructures. Bridges without adequate provisions for earthquake and tsunami loading generally are vulnerable when a tsunami occurs. During the last two disastrous tsunami events (i.e., the tsunami in the Indian Ocean and the tsunami that struck Japan), many bridges were damaged by the waves created by the tsunamis. In this paper, in order to address this crucial problem, we used soft computing techniques to design and develop a process that simulates the effects of perforations in the girders of bridges on reducing the forces applied on the bridge when a tsunami occurs. Soft …


Determination Of The Significant Anthropometry Dimensions For User-Friendly Designs Of Domestic Furniture And Appliances - Experience From A Study In Malaysia Jan 2015

Determination Of The Significant Anthropometry Dimensions For User-Friendly Designs Of Domestic Furniture And Appliances - Experience From A Study In Malaysia

Faculty of Engineering University of Malaya

Future design for the elderly is undoubtedly important for their survival to live independently in this challenging world. Therefore to realize the mentioned design, an anthropometric database for Malaysian elderly population need to be developed. A total of 107 participants took part in the study which involved 61 females and 46 males with ages ranging between 55 and 70 years. An earlier anthropometric database for Malaysian elderly population has been developed. Sixty body dimensions were measured in the study. It is hoped that from this study, the database can be used as a guideline in designing household facilities for the …


Inżynieria Chemiczna Ćw., Wojciech M. Budzianowski Jan 2015

Inżynieria Chemiczna Ćw., Wojciech M. Budzianowski

Wojciech Budzianowski

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Tematyka Prac Doktorskich, Wojciech M. Budzianowski Jan 2015

Tematyka Prac Doktorskich, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Field Monitoring Of Rail Squats Using 3d Ultrasonic Mapping Technique, Sakdirat Kaewunruen, Makoto Ishida Nov 2014

Field Monitoring Of Rail Squats Using 3d Ultrasonic Mapping Technique, Sakdirat Kaewunruen, Makoto Ishida

Sakdirat Kaewunruen

Rail squats and studs are typically classified as the propagation of any cracks that have grown longitudinally through the subsurface. Some of the cracks could propagate to the bottom of rails transversely, which have branched from the initial longitudinal cracks with a depression of rail surface. The rail defects are commonly referred to as ‘squats’ when they were initiated from damage layer caused by rolling contact fatigue, and as ‘studs’ when they were associated with white etching layer caused by the transform from pearlitic steel due to friction heat generated by wheel sliding or excessive traction. Such above-mentioned rail defects …


Free Vibrations Of Interspersed Railway Track Systems In Three-Dimensional Space, Sakdirat Kaewunruen, Alex M. Remennikov, Akira Aikawa, Hirotaka Sakai Apr 2014

Free Vibrations Of Interspersed Railway Track Systems In Three-Dimensional Space, Sakdirat Kaewunruen, Alex M. Remennikov, Akira Aikawa, Hirotaka Sakai

Sakdirat Kaewunruen

Statistically, the actual loading conditions for railway tracks are rather dynamic and transient. The dynamic loadings due to train and track interactions redistribute from the rails to the rail pad, from the rail pad to the railway sleeper, and from the railway sleeper to the underlying ground. Commonly, railway sleeper in track systems is modeled as a beam on elastic foundation. This study makes use of a calibrated finite element model of railway sleepers in a track system, in order to investigate the resonant frequencies and associated mode shapes of railway components in interspersed track systems. The numerical model takes …


Dynamic Responses Of Railway Bridge Ends: A Systems Performance Improvement By Application Of Ballast Glue/Bond, Sakdirat Kaewunruen Apr 2014

Dynamic Responses Of Railway Bridge Ends: A Systems Performance Improvement By Application Of Ballast Glue/Bond, Sakdirat Kaewunruen

Sakdirat Kaewunruen

Accelerated deterioration of railway bridge approaches often induces downtime or restricted railway operation; and importantly causes more frequent maintenance, which is costly and time-consuming. Such deterioration is believed to occur because of high dynamic impact loading from: the difference of stiffness between the railway track and the bridge; and the poor condition of the track support at the bridge ends. The abrupt change in track stiffness often causes accelerated degradation of the track geometry and components and poor ride quality, demanding higher maintenance. There are a number of improvement programs that have been implemented in order to provide a smooth …


Monitoring In-Service Performance Of Fibre-Reinforced Foamed Urethane Sleepers/Bearers In Railway Urban Turnout Systems, Sakdirat Kaewunruen Mar 2014

Monitoring In-Service Performance Of Fibre-Reinforced Foamed Urethane Sleepers/Bearers In Railway Urban Turnout Systems, Sakdirat Kaewunruen

Sakdirat Kaewunruen

Special track systems used to divert a train to other directions or other tracks are generally called \'railway turnout\'. A traditional turnout system consists of steel rails, switches, crossings, steel plates, fasteners, screw spikes, timber bearers, ballast and formation. The wheel rail contact over the crossing transfer zone has a dip-like shape and can often cause detrimental impact loads on the railway track and its components. The large impact also emits disturbing noises (either impact or ground-borne noise) to railway neighbors. In a brown-field railway track where an existing aged infrastructure requires renewal or maintenance, some physical constraints and construction …


Termodynamika Procesowa I Techniczna Lab., Wojciech M. Budzianowski Jan 2014

Termodynamika Procesowa I Techniczna Lab., Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Tematyka Prac Dyplomowych Dla Studentów Wydziału Mechaniczno-Energetycznego Pwr., Wojciech M. Budzianowski Jan 2014

Tematyka Prac Dyplomowych Dla Studentów Wydziału Mechaniczno-Energetycznego Pwr., Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Tematyka Prac Dyplomowych Dla Studentów Wydziału Chemicznego Pwr., Wojciech M. Budzianowski Jan 2014

Tematyka Prac Dyplomowych Dla Studentów Wydziału Chemicznego Pwr., Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Mechanika Płynów Lab., Wojciech M. Budzianowski Jan 2014

Mechanika Płynów Lab., Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


On The Residual Energy Toughness Of Prestressed Concrete Sleepers In Railway Track Structures Subjected To Repeated Impact Loads, Sakdirat Kaewunruen, Alex M. Remennikov Dec 2013

On The Residual Energy Toughness Of Prestressed Concrete Sleepers In Railway Track Structures Subjected To Repeated Impact Loads, Sakdirat Kaewunruen, Alex M. Remennikov

Sakdirat Kaewunruen

Installed as the crosstie beam support in railway track systems, the prestressed concrete sleepers (or railroad ties) are designed in order to carry and transfer the wheel loads from the rails to the ground. It is nowadays best known that railway tracks are subject to the impact loading conditions, which are attributable to the train operations with either wheel or rail abnormalities such as flat wheels, dipped rails, etc. These loads are of very high magnitude but short duration, as well as there exists the potential of repeated load experience during the design life of the prestressed concrete sleepers. These …


Railway Bridge-Track Interaction Under Elevated Temperatures, Sakdirat Kaewunruen Nov 2013

Railway Bridge-Track Interaction Under Elevated Temperatures, Sakdirat Kaewunruen

Sakdirat Kaewunruen

This paper presents the adaptability to short-term climate variability and extreme events of existing infrastructures in Australia, especially railway track bridges. The main objective of this research was to analyse the interaction between the track and bridge under elevated temperatures. The scope of work was to evaluate the behaviour of the track and bridge interaction throughout temperature ranges experienced in summer periods whereas the expansion and contraction of materials are different in nature. This investigation was emphasised on the differential longitudinal behaviours of railway track and bridge structure. A nonlinear 3D finite element model of a railway bridge (ballast top) …


Acoustic And Dynamic Characteristics Of A Complex Urban Turnout Using Fibre-Reinforced Foamed Urethane (Ffu) Bearers, Sakdirat Kaewunruen Sep 2013

Acoustic And Dynamic Characteristics Of A Complex Urban Turnout Using Fibre-Reinforced Foamed Urethane (Ffu) Bearers, Sakdirat Kaewunruen

Sakdirat Kaewunruen

A special track system used to divert a train to other directions or other tracks is generally called ‘railway turnout’. A traditional turnout system includes rails, switches, crossings (special track components), steel plates, fasteners, screw spikes, timber bearers, ballast and formation. The wheel rail contact over the crossing transfer zone has a dip-like shape and can often cause detrimental impact loads on the railway track and its components. The large impact also emits disturbing noises (either impact or ground-borne noise) to railway neighbors. In a brown-field railway track where an existing aged infrastructure requires renewal or maintenance, some physical constraints …


Active Tuned Mass Dampers For Control Of In-Plane Vibrations Of Wind Turbine Blades, Breiffni Fitzgerald Jan 2013

Active Tuned Mass Dampers For Control Of In-Plane Vibrations Of Wind Turbine Blades, Breiffni Fitzgerald

Breiffni Fitzgerald

This paper investigates the use of active tuned mass dampers (ATMDs) for the mitigation of in-plane vibrations in rotating wind turbine blades. The rotating wind turbine blades with tower interaction represent time-varying dynamical systems with periodically varying mass, stiffness, and damping matrices. The aim of this paper is to determine whether ATMDs could be used to reduce in-plane blade vibrations in wind turbines with better performance than compared with their passive counterparts. A Euler–Lagrangian wind turbine mathematical model based on energy formulation was developed for this purpose, which considers the structural dynamics of the system and the interaction between in-plane …


Mechaniczny Rozdział Faz Proj., Wojciech M. Budzianowski Jan 2013

Mechaniczny Rozdział Faz Proj., Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Challenges And Prospects Of Processes Utilising Carbonic Anhydrase For Co2 Separation, Patrycja Szeligiewicz, Wojciech M. Budzianowski Jan 2013

Challenges And Prospects Of Processes Utilising Carbonic Anhydrase For Co2 Separation, Patrycja Szeligiewicz, Wojciech M. Budzianowski

Wojciech Budzianowski

This article provides an analysis of processes for separation CO2 by using carbonic anhydrase enzyme with particular emphasis on reactive-membrane solutions. Three available processes are characterised. Main challenges and prospects are given. It is found that in view of numerous challenges practical applications of these processes will be difficult in near future. Further research is therefore needed for improving existing processes through finding methods for eliminating their main drawbacks such as short lifetime of carbonic anhydrase or low resistance of reactive membrane systems to impurities contained in flue gases from power plants.


Climate Change In Cyprus: Impacts And Adaptation Measures, Theodoros Zachariadis Mar 2012

Climate Change In Cyprus: Impacts And Adaptation Measures, Theodoros Zachariadis

Theodoros Zachariadis

No abstract provided.