65 research outputs found
Design and development of a reduced form-factor high accuracy three-axis teslameter
Acknowledgments: The authors would like to thank Reuben Debono for his useful guidance and help in the
PCB assembly of the instruments at the Electronic Systems Lab at the Faculty of Engineering at University of
Malta. The authors would like to thank R. Ganter, project leader of the Athos undulator beamline and H-H.
Braun, SwissFEL machine director, for their constant support throughout the entire project. The authors would
like to thank Sasa Spasic and his team at Sentronis facilities for their fruitful discussions and their guidance
during testing.A novel three-axis teslameter and other similar machines have been designed and developed for SwissFEL at the Paul Scherrer Institute (PSI). The developed instrument will be used for high fidelity characterisation and optimisation of the undulators for the ATHOS soft X-ray beamline. The teslameter incorporates analogue signal conditioning for the three-axes interface to a SENIS Hall probe, an interface to a Heidenhain linear absolute encoder and an on-board high-resolution 24-bit analogue-to-digital conversion. This is in contrast to the old instrumentation setup used, which only comprises the analogue circuitry with digitization being done externally to the instrument. The new instrument fits in a volumetric space of 150 mm × 50 mm × 45 mm, being very compact in size and also compatible with the in-vacuum undulators. This paper describes the design and the development of the different components of the teslameter. Performance results are presented that demonstrate offset fluctuation and drift (0.1–10 Hz) with a standard deviation of 0.78 µT and a broadband noise (10–500 Hz) of 2.05 µT with an acquisition frequency of 2 kHz.peer-reviewe
Convergence research into the applicability of smart contracts in construction projects
This study presents a new research into the applicability of smart contract approach (SCA) in construction projects, and it consists of two parts, including the identification of limitations and challenges associated with traditional construction contract approach in comparison with the SCA, and the establishment of a conceptual framework to facilitate further research and development in adopting SCA at tactical and operational level in construction projects. The study adopted a systematic literature review first to identify limitations and challenges to adopting SCA in construction projects, and then a system analysis and design to establish a conceptual framework in response to identified limitations and challenges at strategic level. This study shows a list of identified limitations and challenges of traditional construction contract approach in the digital construction era, and a strategic framework as one technical solution to overcome the limitations and to tackle the challenges. This study presents a list of limitations and challenges that traditional construction contract approach has in the digital construction era and a strategic resolution to adopting SCA in construction projects. These research outcomes are practice oriented with connections to further research, development and practice in relation to SCA. This research establishes a connection between the identified limitations and challenges of traditional construction contract approach and the adoption of SCA at strategic level. This connection including the strategic framework can well inform further research into tactical and operational solutions for adopting SCA in the digital construction era
Convergence research into agile lean construction for major project risks management
This study describes an ongoing PhD research into a novel technical integration of agile project management (APM) and lean construction (LC) for risks management in major construction project delivery. This study describes four research methods adopted, including systematic literature review to justify the need for the described research, system analysis and design to establish a managerial prototype of agile lean construction (ALC) integrated risk management process map called ALCPM, and questionnaire-based survey and case study to verify the ALCPM prototype. In addition to introducing this research project and the ALCPM prototype, this study describes contemporary issues and challenges in project risk management in connection with ALC. The ALCPM methodology with expected research findings will include a re-engineered process map to achieve the advantages from ALC integration to enhance risks management practice in major construction project delivery. This study will also discuss anticipated outcomes from questionnaire based survey and case study to verify the ALCPM methodology and to explore its utilization in a scenario-based case study. The described research puts forward a generic ALCPM methodology for risks management in major construction projects. This methodology can inform academic research and professional practices in risks management for construction projects, especially major ones where project performance enhancement against risks is on the agenda. This study puts forward a generic ALCPM methodology to support theoretical development of risks management in construction management. Both research justification and proposed process map described in this study have established the preliminary research with valuable findings to inform further development
The Australian Space Eye: studying the history of galaxy formation with a CubeSat
The Australian Space Eye is a proposed astronomical telescope based on a 6U
CubeSat platform. The Space Eye will exploit the low level of systematic errors
achievable with a small space based telescope to enable high accuracy
measurements of the optical extragalactic background light and low surface
brightness emission around nearby galaxies. This project is also a demonstrator
for several technologies with general applicability to astronomical
observations from nanosatellites. Space Eye is based around a 90 mm aperture
clear aperture all refractive telescope for broadband wide field imaging in the
i and z bands.Comment: 19 pages, 14 figures, submitted for publication as Proc. SPIE 9904,
9904-56 (SPIE Astronomical Telescopes & Instrumentation 2016
A systemic review to identify grand challenges in adopting lean construction
This study presents current research into identifying grand challenges in adopting principles and techniques of Lean Construction (LC) in construction management. This research is conducted through using nine square process (NSP), which is a practical qualitative technique of the TRIZ (Theory of Inventive Problem Solving) to form a systematic literature review. Findings: This research yields a structured LC oriented research documentation to support technical analysis to identify grand challenges in relevant research and practice. The structure and contents of this research documentation are developed and accumulated respectively through the NSP connecting with a wide range of relevant literature from academic research and professional practice. This study also presents a list of grand challenges identified from the research with regard to further LC oriented research and development, and these include the change of enterprise culture, the cost of implementation, and the lack of practical knowledge. The described research demonstrates a new research initiative in a systemic literature review to establish a research documentation, which is used to identify grand challenges in research and practice. It is expected that the structure of research documentation and identified grand challenges can well inform further research in innovative solutions for adopting LC in construction management. This study presents a unique example to use NSP to establish a systematic literature view in the context of LC and grand challenges in further research and practice. Both research method and findings are valuable for further research and development in adopting LC in construction management
A text mining approach to trend analysis of research on building information modelling in the Middle East and North Africa
This study describes an ongoing research into using text mining technique to identify trends in research on BIM (building information model/modelling/management) in the Middle East and North Africa (MENA). The described research has collected relevant studies on BIM and analysed changes in the patterns and research trends in the selected research period. The research is conducted by using literature review to justify the research aim and objectives, data collection from publication databases to establish a relevant dataset, and data analysis through text mining to identify the patterns and trends in BIM oriented research in MENA. The above research enabled establishing an original view on patterns and trends in BIM oriented research in the MENA. The text analysis approach developed from the described research can be useful for further research into developing a generic text analysis roadmap (TAR) to facilitate academic research and professional practice by using text mining technique in construction management within BIM pervasive project environment. Based on the preliminary research, this study provides useful information on how to use text mining technique to identify patterns and trends in BIM oriented research in the MENA. Research ndings described in this study can well inform further research in related areas
A lifecycle social network analysis framework for BIM adoption in major construction projects
This study presents a critical review and discussions on the need for a project lifecycle oriented social network analysis (SNA) framework to enhance the effectiveness and efficiency of adopting BIM as a socio-technical subsystem in major construction project delivery. The described research adopted literature review and technical analysis in the context of using SNA to support managerial performance enhancement in BIM pervasive major project environment, and to develop a lifecycle oriented SNA framework at strategic level for major construction project management. Based on a preliminary research, this study rst provides information on how BIM adoption can interact with major construction project stakeholders in such a new socio-technical subsystem with regard to their needs, responsibilities, and possible contributions, and then presents a strategic framework to integrate SNA in major project management. The SNA framework presented here can inform further research and development with regard to managerial activities at tactical and operational level throughout the lifecycle of major construction project where challenges from BIM adoption, which has been forming a new socio-technical subsystem, need to be well tackled in major construction project delivery. The described research originally established a strategic framework for using SNA to enhance managerial performance in BIM pervasive major construction project management. This SNA framework is established through literature review and technical analysis in related areas, and can well inform further research and development to facilitate the adoption of this framework at tactical and operational level for project clients
Spatially Resolved Operando Synchrotron-Based X-Ray Diffraction Measurements of Ni-Rich Cathodes for Li-Ion Batteries
Understanding the performance of commercially relevant cathode materials for lithium-ion (Li-ion) batteries is vital to realize the potential of high-capacity materials for automotive applications. Of particular interest is the spatial variation of crystallographic behavior across (what can be) highly inhomogeneous electrodes. In this work, a high-resolution X-ray diffraction technique was used to obtain operando transmission measurements of Li-ion pouch cells to measure the spatial variances in the cell during electrochemical cycling. Through spatially resolved investigations of the crystallographic structures, the distribution of states of charge has been elucidated. A larger portion of the charging is accounted for by the central parts, with the edges and corners delithiating to a lesser extent for a given average electrode voltage. The cells were cycled to different upper cutoff voltages (4.2 and 4.3Â V vs. graphite) and C-rates (0.5, 1, and 3C) to study the effect on the structure of the NMC811 cathode. By combining this rapid data collection method with a detailed Rietveld refinement of degraded NMC811, the spatial dependence of the degradation caused by long-term cycling (900 cycles) has also been shown. The variance shown in the pristine measurements is exaggerated in the aged cells with the edges and corners offering an even lower percentage of the charge. Measurements collected at the very edge of the cell have also highlighted the importance of electrode alignment, with a misalignment of less than 0.5Â mm leading to significantly reduced electrochemical activity in that area.</jats:p
Intensity changes in a continuous tone: Auditory cortical potentials comparison with frequency changes
Targeted Deletion of Neuropeptide Y (NPY) Modulates Experimental Colitis
Neurogenic inflammation plays a major role in the pathogenesis of inflammatory bowel disease (IBD). We examined the role of neuropeptide Y (NPY) and neuronal nitric oxide synthase (nNOS) in modulating colitis.Colitis was induced by administration of dextran sodium sulphate (3% DSS) or streptomycin pre-treated Salmonella typhimurium (S.T.) in wild type (WT) and NPY (NPY(-/-)) knockout mice. Colitis was assessed by clinical score, histological score and myeloperoxidase activity. NPY and nNOS expression was assessed by immunostaining. Oxidative stress was assessed by measuring catalase activity, glutathione and nitrite levels. Colonic motility was assessed by isometric muscle recording in WT and DSS-treated mice.DSS/S.T. induced an increase in enteric neuronal NPY and nNOS expression in WT mice. WT mice were more susceptible to inflammation compared to NPY(-/-) as indicated by higher clinical & histological scores, and myeloperoxidase (MPO) activity (p<0.01). DSS-WT mice had increased nitrite, decreased glutathione (GSH) levels and increased catalase activity indicating more oxidative stress. The lower histological scores, MPO and chemokine KC in S.T.-treated nNOS(-/-) and NPY(-/-)/nNOS(-/-) mice supported the finding that loss of NPY-induced nNOS attenuated inflammation. The inflammation resulted in chronic impairment of colonic motility in DSS-WT mice. NPY -treated rat enteric neurons in vitro exhibited increased nitrite and TNF-alpha production.NPY mediated increase in nNOS is a determinant of oxidative stress and subsequent inflammation. Our study highlights the role of neuronal NPY and nNOS as mediators of inflammatory processes in IBD
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