A solid state Marx generator with a novel configuration

The new configuration proposed in this paper for Marx Generator (MG.) aims to generate high voltage for pulsed power applications through reduced number of semiconductor components with a more efficient load supplying process. The main idea is to charge two groups of capacitors in parallel through an inductor and take the advantage of resonant phenomenon in charging each capacitor up to a double input voltage level. In each resonant half a cycle, one of those capacitor groups are charged, and eventually the charged capacitors will be connected in series and the summation of the capacitor voltages can be appeared at the output of the topology. This topology can be considered as a modified Marx generator which works based on the resonant concept. Simulated models of this converter have been investigated in Matlab/SIMULINK platform and the acquired results fully satisfy the anticipations in proper operation of the converter.

The voices of the exegesis

In a recent journal article, Luke Jaaniste and I identified an emergent model of exegesis. From a content analysis of submitted exegeses within a local archive, we identified an approach that is quite different from the traditional thesis, but is also distinct from previously identified forms of exegesis, which Milech and Schilo have described as a ‘context model’ (which assumes the voice of academic objectivity and provides an historical or theoretical context for the creative practice) and a ‘commentary’ model’ (which takes the form of a first person reflection on the challenges, insights and achievements of the practice). The model we identified combines these dichotomous forms and assumes a dual orientation–looking outwards to the established field of research, exemplars and theories, and inwards to the methodologies, processes and outcomes of the practice. We went on to argue that this ‘connective’ exegesis offers clear benefits to the researcher in connecting the practice to an established field while allowing the researcher to demonstrate how the methods have led to outcomes that advance the field in some way. And, while it helps the candidate to articulate objective claims for research innovation, it enables them to retain a voiced, personal relationship with their practice. However, it also poses considerable complexities and challenges in the writing. It requires a reconciliation of multi-perspectival subject positions: the disinterested perspective and academic objectivity of an observer/ethnographer/analyst/theorist at times and the invested perspective of the practitioner/ producer at others. The author must also contend with a range of writing styles, speech genres and voices: from the formal, polemical voice of the theorist to the personal, questioning and sometimes emotive voice of reflexivity. Moreover, the connective exegesis requires the researcher to synthesize various perspectives, subject positions, writing styles, and voices into a unified and coherent text. In this paper I consider strategies for writing a hybrid, connective exegesis. I first ground the discussion on polyvocality and alternate textual structures through reference to recent discussions in philosophy and critical theory, and point to examples of emergent approaches to texts and practices in related fields. I then return to the collection of archived exegeses to investigate the strategies that postgraduate candidates have adopted to resolve the problems that arise from a polyvocal, connective exegesis.

Molecular dynamics study of dynamic buckling properties of nanowires with defects

Based on the embedded atom method (EAM) and molecular dynamics (MD) method, the deformation properties of Cu nanowires with different single defects under dynamic compression have been studied. The mechanical behaviours of the perfect nanowire are first studied, and the critical stress decreases with the increase of the nanowire’s length, which is well agreed with the modified Euler theory. We then consider the effects to the buckling phenomenon resulted from different defects. It is found that obvious decrease of the critical stress is resulted from different defects, and the largest decrease is found in nanowire with the surface vertical defect. Surface defects are found exerting larger influence than internal defects. The buckling duration is found shortened due to different defects except the nanowire with surface horizon defect, which is also found possessing the largest deflection. Different deflections are also observed for different defected nanowires. It is find that due to surface defects, only deflection in one direction is happened, but for internal defects, more complex deflection circumstances are observed.

Measuring transit service reliability using data from web-based transit user survey : a case study at Brisbane, Australia

This paper reports an empirical study on measuring transit service reliability using the data from a Web-based passenger survey on a major transit corridor in Brisbane, Australia. After an introduction of transit service reliability measures, the paper presents the results from the case study including study area, data collection, and reliability measures obtained. This includes data exploration of boarding/arrival lateness, in-vehicle time variation, waiting time variation, and headway adherence. Impacts of peak-period effects and separate operation on service reliability are examined. Relationships between transit service characteristics and passenger waiting time are also discussed. A summary of key findings and an agenda of future research are offered in conclusions.

Selection of solar energy for green building using superiority and inferiority multi-criteria ranking (SIR) method

Green energy is one of the key factors, driving down electricity bill and zero carbon emission generating electricity to green building. However, the climate change and environmental policies are accelerating people to use renewable energy instead of coal-fired (convention type) energy for green building that energy is not environmental friendly. Therefore, solar energy is one of the clean energy solving environmental impact and paying less in electricity fee. The method of solar energy is collecting sun from solar array and saves in battery from which provides necessary electricity to whole house with zero carbon emission. However, in the market a lot of solar arrays suppliers, the aims of this paper attempted to use superiority and inferiority multi-criteria ranking (SIR) method with 13 constraints establishing I-flows and S-flows matrices to evaluate four alternatives solar energies and determining which alternative is the best, providing power to sustainable building. Furthermore, SIR is well-known structured approach of multi-criteria decision support tools and gradually used in construction and building. The outcome of this paper significantly gives an indication to user selecting solar energy.

Advanced numerical study of impact forces on railway sleepers under wheel flat

Wheel-rail interaction is one of the most important research topics in railway engineering. It includes track vibration, track impact response and safety of the track. Track structure failures caused by impact forces can lead to significant economic loss for track owners through damage to rails and to the sleepers beneath. The wheel-rail impact forces occur because of imperfections on the wheels or rails such as wheel flats, irregular wheel profile, rail corrugation and differences in the height of rails connected at a welded joint. In this paper, a finite element model for the wheel flat study is developed by use of the FEA software package ANSYS. The effect of the wheel flat to impact force on sleepers is investigated. It has found that the wheel flat significantly increases impact forces and maximum Von Mises stress, and also delays the peak position of dynamic variation for impact forces on both rail and sleeper.

The impact of the Malaysian code on corporate governance: compliance, institutional investors and stock performance

In 2001, the Malaysian Code on Corporate Governance (MCCG) became an integral part of the Bursa Malaysia Listing Rules, which requires all listed firms to disclose the extent of compliance with the MCCG. Our panel analysis of 440 firms from 1999 to 2002 finds that corporate governance reform in Malaysia has been successful, with a significant improvement in governance practices. The relationship between ownership by the Employees Provident Fund (EPF) and corporate governance has strengthened during the period subsequent to the reform, in line with the lead role taken by the EPF in establishing the Minority Shareholders Watchdog Group. The implementation of MCCG has had a substantial effect on shareholders' wealth, increasing stock prices by an average of about 4.8%. Although there is no evidence that politically connected firms perform better, political connections do have a significantly negative effect on corporate governance, which is mitigated by institutional ownership.

Using Fiber Bragg Grating (FBG) sensors for vertical displacement measurement of bridges

In many bridges, vertical displacements are one of the most relevant parameters for structural health monitoring in both the short and long terms. Bridge managers around the globe are always looking for a simple way to measure vertical displacements of bridges. However, it is difficult to carry out such measurements. On the other hand, in recent years, with the advancement of fiber-optic technologies, fiber Bragg grating (FBG) sensors are more commonly used in structural health monitoring due to their outstanding advantages including multiplexing capability, immunity of electromagnetic interference as well as high resolution and accuracy. For these reasons, using FBG sensors is proposed to develop a simple, inexpensive and practical method to measure vertical displacements of bridges. A curvature approach for vertical displacement measurement using curvature measurements is proposed. In addition, with the successful development of a FBG tilt sensors, an inclination approach is also proposed using inclination measurements. A series of simulation tests of a full-scale bridge was conducted. It shows that both the approaches can be implemented to determine vertical displacements for bridges with various support conditions, varying stiffness (EI) along the spans and without any prior known loading. These approaches can thus measure vertical displacements for most of slab-on-girder and box-girder bridges. Moreover, with the advantages of FBG sensors, they can be implemented to monitor bridge behavior remotely and in real time. Further recommendations of these approaches for developments will also be discussed at the end of the paper.

Approaches to acquiring ‘doctorateness’ in the creative industries : an Australian perspective

Over the last two decades, particularly in Australia and the UK, the doctoral landscape has changed considerably with increasingly hybridised approaches to methodologies and research strategies as well as greater choice of examinable outputs. This paper provides an overview of doctoral practices that are emerging in the context of the creative industries, with a focus on practice-led approaches within the Doctor of Philosophy and recent developments in professional doctorates, from a predominantly Australian perspective. In interrogating what constitutes ‘doctorateness’ in this context, the paper examines some of the diverse theoretical principles which foreground the practitioner/researcher, methodological approaches that incorporate tacit knowledge and reflective practice together with qualitative strategies, blended learning delivery modes, and flexible doctoral outputs; and how these are shaping this shifting environment. The paper concludes with a study of the Doctor of Creative Industries at Queensland University of Technology as one model of an interdisciplinary professional research doctorate.

Condition monitoring and diagnosis of injector faults in a diesel engine using in-cylinder pressure and acoustic emission techniques

Failing injectors are one of the most common faults in diesel engines. The severity of these faults could have serious effects on diesel engine operations such as engine misfire, knocking, insufficient power output or even cause a complete engine breakdown. It is thus essential to prevent such faults from occurring by monitoring the condition of these injectors. In this paper, the authors present the results of an experimental investigation on identifying the signal characteristics of a simulated incipient injector fault in a diesel engine using both in-cylinder pressure and acoustic emission (AE) techniques. A time waveform event driven synchronous averaging technique was used to minimize or eliminate the effect of engine speed variation and amplitude fluctuation. It was found that AE is an effective method to detect the simulated injector fault in both time (crank angle) and frequency (order) domains. It was also shown that the time domain in-cylinder pressure signal is a poor indicator for condition monitoring and diagnosis of the simulated injector fault due to the small effect of the simulated fault on the engine combustion process. Nevertheless, good correlations between the simulated injector fault and the lower order components of the enveloped in-cylinder pressure spectrum were found at various engine loading conditions.

Structural damage identification with noise polluted Frequency Response Functions (FRFs)

Damage detection in structures has become increasingly important in recent years. While a number of damage detection and localization methods have been proposed, very few attempts have been made to explore the structure damage with noise polluted data which is unavoidable effect in real world. The measurement data are contaminated by noise because of test environment as well as electronic devices and this noise tend to give error results with structural damage identification methods. Therefore it is important to investigate a method which can perform better with noise polluted data. This paper introduces a new damage index using principal component analysis (PCA) for damage detection of building structures being able to accept noise polluted frequency response functions (FRFs) as input. The FRF data are obtained from the function datagen of MATLAB program which is available on the web site of the IASC-ASCE (International Association for Structural Control– American Society of Civil Engineers) Structural Health Monitoring (SHM) Task Group. The proposed method involves a five-stage process: calculation of FRFs, calculation of damage index values using proposed algorithm, development of the artificial neural networks and introducing damage indices as input parameters and damage detection of the structure. This paper briefly describes the methodology and the results obtained in detecting damage in all six cases of the benchmark study with different noise levels. The proposed method is applied to a benchmark problem sponsored by the IASC-ASCE Task Group on Structural Health Monitoring, which was developed in order to facilitate the comparison of various damage identification methods. The illustrated results show that the PCA-based algorithm is effective for structural health monitoring with noise polluted FRFs which is of common occurrence when dealing with industrial structures.

Educating for change : a case for a pedagogy of desire in design eduation

Despite major inroads in demystifying creativity for the non-design disciplines, there has been very little movement in the design disciplines themselves beyond traditional paradigms. As argued in this paper, this is particularly noticeable in design education where traditional pedagogical approaches persist despite the emergence of new experimental pedagogies and the possibilities and opportunities they offer. In response, this paper describes what is revealed when a ‘pedagogy of desire’ is used as a critical lens to reflect on an experience of developing and implementing a first year interior design program involving first and second year undergraduate interior design and architecture students. Implications drawn from the review are presented and a case made for continuing experimentation and development of a pedagogy of desire for design learning and teaching.

A cross-cultural approach towards designing digital noticeboards with a remote aboriginal community

This working paper reflects upon the opportunities and challenges of designing a form of digital noticeboard system with a remote Aboriginal community that supports their aspirations for both internal and external communication. The project itself has evolved from a relationship built through ecological work between scientists and the local community on the Groote Eylandt archipelago to study native populations of animal species over the long term. In the course of this work the aspiration has emerged to explore how digital noticeboards might support communication on the island and externally. This paper introduces the community, the context and the history of the project. We then reflect upon the science project, its outcomes and a framework empowering the Aboriginal viewpoint, in order to draw lessons for extending what we see as a pragmatic and relationship based approach towards cross-cultural design.

The concept of smart cities

Rapid urbanization has resulted in migration of people in urban areas and spatial expansion of urban infrastructures, consequently causing many undesirable malaises and challenges. Concerned with the uncontrolled growth of cities and the associated malaises, there have been numerous initiatives to promote a more rational development of cities. The idea of making cities smart is one of the most promising initiatives which have been a subject of research and development in modern cities. Despite the many activities and initiatives to promote smartness in cities, there is little agreement on what constitute smartness in a city. This inevitably leads to a diversified ways of defining smart cities. By reviewing the existing definitions of smart cities, this paper proposes a framework to define and measure a city’s smartness in a more correct manner.

Value management in infrastructure project design : unlocking the project team’s creativity

Value Management (VM) is a proven methodology that provides a structured framework using supporting tools and techniques that facilitate effective decision-making in many types of projects, thus achieving ‘best value’ for clients. It offers an exceptionally robust approach to exploring the need and function of projects to be aligned with client’s objectives. The functional analysis and creativity phases of VM are crucial as it focused on utilising innovative thinking to understand the objectives of clients’ projects and provide value-adding solutions at the early discovery stages of projects. There is however a perception of VM as just being another cost-cutting tool, which has overshadowed the fundamental benefits of the method, therefore negating both influence and wider use in the construction industry. This paper describes findings from a series of case studies conducted at project and corporate levels of a current public funded infrastructure projects in Malaysia. The study aims to investigate VM processes practised by the project client organisation and evaluate the effects of project team involvement in VM workshops during the design-stage of these projects. The focus of the study is on how issues related to ‘upstream’ infrastructure design aimed at improving ‘downstream’ construction process on-site, are being resolved through multi-disciplinary team consideration and decision-making. Findings from the case studies indicate that the mix of disciplines of project team members at a design-stage of a VM workshop has minimal influence on improving construction processes. However, the degree of interaction, institutionalized thinking, cultural dimensions and visualization aids adopted, have a significant impact in maximizing creativity amongst project team members during VM workshop. The case studies conducted for this research have focused on infrastructure projects that utilise traditional VM workshop as client’s chosen VM methodology to review and develop designs. Documents review and semi-structured interview with project teams are used as data collection techniques for the case study. The significant outcomes of this research are expected to offer alternative perspectives for construction professionals and clients to minimise the constraints and strengthen strategies for implementing VM on future projects.