A gradient flow approach to robust pole assignment in second-order systems

Assignment for second-order systems is considered. It is shown that assignment can be achieved by solving a linear matrix equation or linear system. An objective function measuring the robustness of the closed-loop spectrum is minimized via gradient flow.published_or_final_versio

Gastro-oesophageal reflux in bronchiectasis

published_or_final_versio

Designing CALL for learning Chinese characters

Despite the enormity of its quantity, printed or written forms of Chinese characters are composed from a limited number of common components. For example, the characters for pond( ), lake( ), stream( ), river ( ), sea( ) and ocean( ) all contain a component in common, a three-dot component representing water. When this clue is explicitly highlighted to students, the learning of Chinese characters can be greatly enhanced. Using a computer to help students to develop this kind of structural awareness about language learning has not yet been thoroughly examined. This paper reports on the design of CALL software based on a pedagogic method which helps students to develop the higher order skills to analyse and categorise Chinese characters by using components. The result of the classroom experiment has shown supportive evidence on the feasibility and the need of integrating the software with an affective and contextual way of teaching Chinese characters.postprin

Asymmetric-detection time-stretch optical microscopy (ATOM) for high-contrast and high-speed microfluidic cellular imaging

High-throughput cellular imaging is acclaimed as captivating yet challenging in biomedical diagnostics. We have demonstrated a new imaging modality, asymmetric-detection time-stretch optical microscopy (ATOM), by incorporating a simple detection scheme which is a further advancement in time-stretch microscopy - a viable solution to achieve high-speed and high-throughput cellular imaging. Through the asymmetric-detection scheme in ATOM, the time-stretch image contrast is enhanced through accessing to the phase-gradient information. With the operation in the 1 μm wavelength range, we demonstrate high-resolution and high-contrast cellular imaging in ultrafast microfluidic flow (up to 10 m/s) by ATOM - achieving an imaging throughput equivalent to 100,000 cells/sec. © 2014 SPIE.published_or_final_versio

Revision of the genus Centrophorus (Squaliformes: Centrophoridae): Part 1-Redescription of Centrophorus granulosus (Bloch & Schneider), a senior synonym of C-acus Garman and C-niaukang Teng

The genus Centrophorus is one of the most taxonomically complex and confusing elasmobranch groups. A revision of this group is currently underway and this first paper sets an important foundation in this process by redescribing the type species of the genus-Centrophorus granulosus. This taxon name has been previously applied to two different morphotypes: a large species \u3e 1.5 m TL and a smaller species similar to 1 m TL. Centrophorus acus and C. niaukang are the most commonly used names applied to the larger morphotype. The original description of C. granulosus was based on a large specimen of similar to 1.5 m TL, but subsequent redescriptions were based on either of the large or small morphotypes. Centrophorus granulosus is herein redescribed as a large species and a neotype is designated. Centrophorus acus and C. niaukang are found to be junior synonyms of C. granulosus. Centrophorus granulosus is distinguishable from its congeners by its large size, dermal denticle shape, colouration and a number of morphological and biological characteristics. Ontogenetic changes in morphology, dentition and denticle shape for this species are described in detail

Contradictions of slate formation resolved?

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62973/1/392348a0.pd

Green energy technology

Our environment is facing several serious challenges from energy utilization, such as fossil fuel exhaustion, air pollution, deteriorated atmospheric greenhouse effect, global warming, climate change, etc [...]</jats:p

Cyclic deformation characteristics of S355 and S690 steels under different loading protocols

Despite of excellent high strength to self-weight ratios of the S690 steels, when compared with the S355 steels, there is a widespread concern regarding the ductility of the S690 steels. It is generally considered that the ductility of the S690 steels is significantly lower than that of the S355 steels – this is the general understandings the authors attempt to investigate. This paper presents an experimental investigation into cyclic deformation characteristics of both S355 and S690 steels through low-cycle high-strain cyclic tests with two different loading protocols. A detailed account of the results of 32 cyclic tests on both the S355 and the S690 funnel-shaped coupons is presented. Effects of four different target strains and two different loading frequencies are also examined in details. For the ranges of loading protocols, strain amplitudes, and frequencies considered, the hysteretic responses of these coupons of the two steels are compared directly in terms of engineering stress–strain curves based on their nominal diameters. Microstructures of the fractured coupons of the two steels are also identified for comparison. Contrary to the general understandings, it is demonstrated that the high strength S690 steels do have a good ductility under both monotonic and cyclic actions. Moreover, depending on specific loading protocols and target strains, the cyclic deformation characteristics of the S690 steels are demonstrated to be superior to those of the S355 steels in terms of the number of cycles completed prior to failure and their corresponding energy dissipation characteristic under various target strains up to ±10.0%. The findings of this experimental investigation highlight the importance of establishing ductility requirements and cyclic deformation characteristics for the high strength S690 steels in accordance with specifically designed cyclic tests rather than relying solely on conventional monotonic tensile tests

Bolt looseness detection using Spectral Kurtosis analysis for structural health monitoring

Bolt looseness is a major problem for high valued infrastructure assets such as bridges. Historical data indicates failure in the operating bridges is related to bolted joints. This reveals defects generated by small components can leads to major problem thus early detection is required. In this paper, a novel methodology to characterize the bolt looseness using optimal filtering of vibration data is proposed. A Spectral Kurtosis (SK) based optimal filter is designed to extract frequencies that are generated by bolt looseness. The filter is capable of extracting weak signatures (hidden in acceleration data) that are generated by bolt looseness. The proposed approach is demonstrated through experiments. Results have indicated that the proposed approach can be reliable and effective in detecting loose bolts of a structure subjected to fluctuating loads.Innovate UK under grant agreement No. 103883. The research has been undertaken as a part of the project entitled “SmartBridge”. The SmartBridge project is a collaboration between the following organisations: James Fisher and Sons plc, TWI Ltd, Brunel University London & Innvotek Ltd