MICROFABRICATION AND MODELLING OF DIELECTRIC ELASTOMER ACTUATORS

Dielectric elastomer actuators (DEAs) are a class of polymeric actuators that have gained prominence over the last decade. A DEA is comprised of a polymer sandwiched between two compliant electrodes. When voltage is applied between the two electrodes, electrostatic attraction between the electrodes compresses the elastomer in that direction and stretches it in the other two directions. DEAs produce dimensional changes (strains) up to 300% upon application of an electric field. DEAs have tremendous potential for applications requiring large displacements and have been demonstrated for many macro-scale (centimeter and larger) applications such as robots, loudspeakers, and motors. There are potentially many useful applications for micro-scale DEAs (less than millimeter-sized devices with micron-sized actuators) in the fields of micro-robotics, micro-optics, and micro-fluidics. However, miniaturization of DEAs is challenging because many of the materials and DEA fabrication methods used on the macro-scale cannot be adapted for micro-scale fabrication of DEAs. This thesis explores the feasibility of developing fabrication strategies for micro-scale DEAs by adapting micro-electromechanical systems (MEMS) technology. In addition, fabrication protocols for micro-scale DEAs have been developed. The other aspect of this thesis is the design of bending DEAs. Benders are useful because for a given actuation strain, greater deflection can be observed by controlling the stiffnesses and thicknesses of different layers. A general guideline for designing bending DEA configurations such as unimorph, bimorph, and multilayer stacks was developed using a multilayer analytical model. The design optimization is based on the effect of thickness and stiffness of different layers on curvature, blocked force, and work. Complaint electrodes and their design are important for DEAs to enable the elastomer to stretch unrestricted. Thus, design criteria for the fabrication of crenellated electrodes and crenellated elastomers with electrodes were investigated. This guideline enabled design of structures with appropriate axial or bending stiffnesses based on the amplitude, angle, length, and thickness. Simple analytical equations for axial and bending stiffness for crenellated electrodes with different shapes were derived. In addition, numerical simulations of crenellated elastomer with stiff electrode were performe

The role of union leader-member relationship capital within trade union for mental health

Objective – There are three main objectives of this study. First, this study is to examine the influence of union effectiveness and perceived union support on union relationship capital to achieve positive mental health in the workplace. Next, this study is to investigate the interdependency of the dimensions of union relationship capital: communication, trust and commitment between the union leader and union members in improving and strengthening the relationship within the union. Lastly, this study is to investigate the role of relationship capital as the mediator between union effectiveness, perceived union support and mental health. Methodology/Technique – A total of 600 questionnaires completed by trade union leaders and members in manufacturing sector based in Peninsular Malaysia were analysed using SEM (AMOS) and SPSS. The relationship between union effectiveness, perceived union support, union relationship capital and mental health were analysed using SEM. But the interaction between communication, trust and commitment were analysed using SPSS. Findings – The results demonstrated that union effectiveness and perceived union support are determinants for union relationship capital. The finding showed that communication, trust and commitment are interdependent. Furthermore, the finding also shows a significant relationship between union relationship capital and mental health. Novelty – It is said that good communication, trust and commitment within the trade union can increase cohesiveness and strengthen the trade union. A strong union can lead to positive mental health in the workplace. Type of Paper: Empirical

Detection of aeromonas hydrophila using fiber optic sensor

Pathogenesis including chronic infections, inflammation, malignancy, tissue break down, and immune system disorder are linked with pathogens that affect human health with massive diseases. Aeromonas hydrophila infections increasingly recognized as a serious worldwide public health concern. Although numerous antibiotics and vaccination have been introduced to protect against diseases, some pathogen continues to threaten living life. However, the current pathogen detection method which based on molecular culture and PCR techniques are fundamentally slow and time consuming. Consequently, these discoveries have created awareness in development of effective pathogen detecting tool to control the related quality and prevent further infections. In recent time, several researchers have attempted to develop rapid detecting tool. Despite advanced engineering, there is still need for an accurate and rapid pathogen detection tool. Thus, this research has been carried out to highlight mostly on detection of Aeromonas hydrophila by using optical biosensor as contribution of this study while Escherichia coli and Saccharomyces cerevisiae were used for justification of the findings as part of the experimental work. In this study, we proposed an optical based biosensor as relatively an accurate method of early effective detection of pathogen or infectious agent. Fiber optic flow cell and fiber optic microchannel were used in this study for detection of pathogens. Fiber optic flow cell was used as preliminary study for optical characteristic of the pathogens used. Then optical microchannel was fabricated with fiber optics by using photolithography method. Fiber optic was chosen as signal receiving and transmitting medium due to its excellent plus rapid signal delivering feature. Fiber optic biosensor is based on light scattering, absorption and optical properties of the microorganisms. The chemical composition, energy, the total nucleotides and photopigments will define the absorption properties of each microorganism. The difference in peak absorbance spectra of microorganism at particular region of wavelength will be manipulated for detection of the sample. Based on the experimental findings, the detection of A.hydrophila and E.coli of any phases (lag,exponential and stationary) were fall in UV spectral region while every phases of S.cerevisiae detection falls in visible spectral region. A.hydrophila was identified at between 350nm to 354nm and E.coli detected at region of 280nm to 285nm by using the microchannel. While, S. cerevisiae recognized in visible region of 570nm to 580nm. The entire detection can be done in less than 10 minutes. These detection regions for each sample have been compared with fiber optic flow cell measurements, spectrophotometer measurement plus theoretical calculations by using Beer Lambert Absorption Law and proved the detection regions were in approximately accurate spectral

Electrochemical tests on the carbon protective layer of a hard disk

10.1016/S0925-9635(02)00038-9Diamond and Related Materials1171409-1415DRMT

Influence of carbon sputtering conditions on corrosion protection of magnetic layer by an electrochemical technique

10.1149/1.1448819Journal of the Electrochemical Society1493B84-B88JESO

Optimal Step-stress test under progressive type I censoring

International audienc

Tenaga kerja pelbagai etnik kajian eksploratif tentang pengaruh etnisiti dalam organisasi kerja sektor swasta

Sektor industri moden dengan tenaga kerja yang terdiri daripada berbilang etnik sudah pastinya membuka ruang dan peluang yang lebih luas bagi individu-individu berinteraksi merentasi sempadan etnik dan perbezaan budaya serta memberi peluang kepada mereka menyertai bersama dalam proses membuat keputusan dalam industri. Justeru, dalam situasi kepelbagaian etnik masyarakat Malaysia keperluan memahami dan mengurus tenaga kerja pelbagai etnik adalah satu isu penting dalam amalan pengurusan sektor industri moden. Kajian ini adalah satu usaha untuk memahami pengaruh keetnikan dalam hubungan antara individu dalam situasi tenaga kerja pelbagai etnik di negeri Sabah. Ini adalah satu kajian tinjauan dengan menggunakan soal selidik. Seramai 432 pekerja dari pelbagai etnik dan pekerjaan telah dipilih daripada beberapa industri Utama yang berbeza di negeri Sabah. Hasil penemuan kajian menunjukkan pengalaman pekerja pelbagai etnik dalam organisasi kerja moden di negeri Sabah kurang dipengaruhi oleh faktor perbezaan etnik dalam interaksi di kalangan pekerja, Begitu pula pengaruhnya ke ataS tanggapan mereka terhadap amalan pihak pengurusan. Dapatan ini menunjukkan bahawa pengaruh keetnikan dan kepelbagaian etnik bukanlah satu isu utama dalam pengurusan organisasi kerja dalam sektor ekonomi moden di negeri Sabah