Recursos de colección

Enlighten (154.243 recursos)

Enlighten is the University of Glasgow's institutional repository service for published research material including peer-reviewed journal articles, published conference papers,books and book chapters

Type = Conference Proceedings

Mostrando recursos 1 - 20 de 2.348

  1. Laser Guided Curved Electric Discharges. Technical Report.

    Clerici, Matteo; Hu, Yi; Milián, Carles; Couairon, Arnaud; Christodoulides, Demetrios N.; Chen, Zhigang; Razzari, Luca; Vidal, François; Légaré, François; Faccio, Daniele; Morandotti, Roberto
    We report laser-guided electric discharges along curved trajectories, and hence around obstacles in line of sight between electrodes. Furthermore, beam self-healing enables direct discharge on target even when the laser beam directly hits the obstacle.

  2. Epsilon near zero metamaterials for ultra-low power nonlinear applications

    Pietrzyk, Monika; Kaipurath, Rashid; Di Falco, Andrea; Faccio, Daniele
    Epsilon-near-zero metamaterial samples, composed of five alternating bi-layers of silica and silver, are fabricated using the electron-beam evaporator. Nonlinear properties of samples are measured using a pulsed Ti:sapphire laser by the z-scan technique. It is observed that the real part of the nonlinear Kerr index is one order of magnitude higher than the values expected from a naive averaging of the corresponding coefficients of metal and dielectric layers (the correct averaging should be performed with respect to the nonlinear susceptibility), so that its value is actually of the same order of magnitude as that of a single silver layer. At...

  3. A Classification of Infographics

    Purchase, Helen C.; Isaacs, Katherine; Bueti, Thomas; Hastings, Ben; Kassam, Aadam; Kim, Allen; van Hoesen, Steffan
    Classifications are useful for describing existing phenomena and guiding further investigation. Several classifications of diagrams have been proposed, typically based on analytical rather than empirical methodologies. A notable exception is the work of Lohse and his colleagues, published in Communications of the ACM in December 1994. The classification of diagrams that Lohse proposed was derived from bottom-up grouping data collected from sixteen participants and based on 60 diagrams. Mean values on ten Likert-scales were used to predict diagram class. We follow a similar methodology to Lohse, using real-world infographics (i.e. embellished data charts) as our stimuli. We propose a structural...

  4. Coherent All-Optical Sygnal Processing with Plasmonic Metamaterials: Demonstration of 100THz Bandwidth and Quantum-Level Operations

    Zheludev, Nikolay I.; Faccio, Daniele
    We report recent experiments demonstrating that coherently controlled redistribution of energy at plasmonic metamaterials can underpin various forms of optical switching and show that devices based on coherent control can operate down to single photon level and with a modulation bandwidth up to 100 THz.

  5. 250-GW Sub-Three-Cycle Multi-Millijoule Mid-IR Pulses Self-Compressed in a YAG plate. Technical Digest.

    Shumakova, Valentina; Malevich, Pavel; Alisauskas, Skirmantas; Voronin, Aleksander; Zheltikov, Aleksei; Faccio, Daniele; Kartashov, Daniil; Maksimenka, Raman; Gitzinger, Gregory; Forget, Nicolas; Baltuska, Andrius; Pugzlys, Audrius
    Virtually lossless self-compression of 10-mJ 3.9-um sub-100 fs pulses in bulk YAG resulting in 9-mJ 33-fs pulses is reported. Generated peak power exceeds 250 GW which is suitable for filamentation in ambient air.

  6. 250-GW Sub-Three-Cycle Multi-Millijoule Mid-IR Pulses Self-Compressed in a YAG plate

    Shumakova, Valentina; Malevich, Pavel; Alisauskas, Skirmantas; Voronin, Aleksander; Zheltikov, Aleksei; Faccio, Daniele; Kartashov, Daniil; Maksimenka, Raman; Gitzinger, Gregory; Forget, Nicolas; Baltuska, Andrius; Pugzlys, Audrius
    Virtually lossless self-compression of 10-mJ 3.9-um sub-100 fs pulses in bulk YAG resulting in 9-mJ 33-fs pulses is reported. Generated peak power exceeds 250 GW which is suitable for filamentation in ambient air.

  7. Learning Rigid Image Registration - Utilizing Convolutional Neural Networks for Medical Image Registration

    Sloan, J.M.; Goatman, K.A.; Siebert, J.P.
    Many traditional computer vision tasks, such as segmentation, have seen large step-changes in accuracy and/or speed with the application of Convolutional Neural Networks (CNNs). Image registration, the alignment of two or more images to a common space, is a fundamental step in many medical imaging workflows. In this paper we investigate whether these techniques can also bring tangible benefits to the registration task. We describe and evaluate the use of convolutional neural networks (CNNs) for both mono- and multi- modality registration and compare their performance to more traditional schemes, namely multi-scale, iterative registration. This paper also investigates incorporating inverse consistency...

  8. A Case Study on Mining Social Media data

    Chan, H. K.; Lacka, E.; Yee, R. W. Y.; Lim, M. K.
    In recent years, usage of social media websites have been soaring. This trend not only limits to personal but corporate web-sites. The latter platforms contain an enormous amount of data posted by customers or users. Without a surprise, the data in corporate social media web-sites are normally link to the products or services provided by the companies. Therefore, the data can be utilized for the sake of companies' benefits. For example, operations management research and practice with the objective to make decisions on product and process design. Nevertheless, little has been done in this area. In this connection, this paper...

  9. On the Optimality of Virtualized Security Function Placement in Multi-Tenant Data Centers

    Ali, Abeer; Anagnostopoulos, Christos; Pezaros, Dimitrios P.

  10. Adoption of Social Media Sites by B2B Companies in China

    Lacka, Ewelina; Chan, Hing Kai; Chong, Alain
    Social media sites have been perceived to be irrelevant in B2B sector. This is because of the perception of poor usability of those sites for B2B marketing. This study while extending Technology Acceptance Model by Nielsen?s Model of Attributes of System Acceptability assesses the impact of usability, utility and perceived usefulness on adoption and use of social media sites in B2B context. The empirical investigation, carried out on a sample of 181 Chinese B2B companies, reveals that users? perception of the usefulness, usability and utility of social media sites drive their adoption and use in the B2B sector. The usefulness...

  11. Automated Measurement of Adherence to Traumatic Brain Injury (TBI) Guidelines using Neurological ICU Data

    Stell, Anthony; Piper, Ian; Moss, Laura
    Using a combination of physiological and treatment information from neurological ICU data-sets, adherence to traumatic brain injury (TBI) guidelines on hypotension, intracranial pressure (ICP) and cerebral perfusion pressure (CPP) is calculated automatically. The ICU output is evaluated to capture pressure events and actions taken by clinical staff for patient management, and are then re-expressed as simplified process models. The official TBI guidelines from the Brain Trauma Foundation are similarly evaluated, so the two structures can be compared and a quantifiable distance between the two calculated (the measure of adherence). The methods used include: the compilation of physiological and treatment information...

  12. Nanotechnology in Multimodal Theranostic Capsule Endoscopy

    Cochran, S.; Button, T.W.; Cox, B.F.; Cumming, D.R.S.; Gourevich, D.; Lay, H.S.; Mulvana, H.; Nathke, I.S.; Stewart, F.
    Video capsule endoscopy (VCE) has become a clinically accepted diagnostic modality in the last 20 years and has established a technological roadmap for other capsule endoscopy (CE) devices, incorporating microscale technology, a local power supply and wireless communication. However, VCE does not provide a therapeutic function and research in therapeutic capsule endoscopy (TCE) has been limited. This paper proposes a new route towards viable TCE based on multiple CE devices including essential nanoscale components. A first device is used for multimodal diagnosis, with quantitative microultrasound as a complement to video imaging. Ultrasound-enhanced fluorescent marking of sites of pathology allows follow-up...

  13. Planning Configuration Relocation on the BonFIRE Infrastructure

    Herry, Herry; Anderson, Paul
    The Nuri configuration tool uses automated planning techniques to reconfigure computing infrastructures from one declarative state to another, while maintaining any required constraints at all stages of the generated workflow. This paper presents the results of our experiments using Nuri to relocate complete 3-tier web applications between two BonFIRE sites. We describe the architecture of the tool and present the results of the experiment which demonstrate that Nuri is capable of planning, and executing this relocation in a reasonable time, with guaranteed constraints on the system throughout the reconfiguration.

  14. Self-compression of Millijoule mid-IR Femtosecond Pulses in Transparent Dielectrics

    Pugzlys, Audrius; Malevich, Pavel; Alisauskas, Skirmantas; Voronin, Alexander A.; Kartashov, Daniil; Baltuska, Andrius; Zheltikov, Aleksei; Faccio, Daniele
    Self-compression of 2.2-mJ, 80-fs mid-IR pulses is achieved using a 1.5-mm-thick CaF2 plate. Femtosecond pulses with peak powers orders of magnitude higher than the self-focusing threshold can undergo self-compression without breaking up into multiple filaments.

  15. Solitonic Regime of Mid-infrared Filamentation at Highly Overcritical Power in Transparent Solids

    Kartashov, Daniil; Malevich, Pavel; Alisauskas, Skirmantas; Pug¡zlys, Audrius; Voronin, Alexander; Zheltikov, Alexei; Faccio, Daniele; Baltuska, Andrius
    Filamentation of femtosecond pulses in transparent solids with anomalous group-velocity dispersion is investigated for a broad range of the peak powers. Solitonic self-compression of multi-millijoule mid-IR pulses is achieved using a 1.5-mm-thick CaF2 plate.

  16. Benchmarking Electrical Loss in Rectangular Metallic Waveguide at Submillimeter Wavelengths

    Ridler, Nick; Li, Chong
    A series of documentary standards has recently been published (the IEEE 1785 series) that provides specification details for rectangular metallic waveguides used at frequencies from 110 GHz to at least 3.3 THz. This includes values of electrical loss (both reflection and transmission) for these waveguides. However, the values specified in these standards are based on calculated (i.e. modelled) performance and not measured values for real waveguide devices. This paper presents measured values of loss for commercially available waveguides in this frequency range. A comparison is given between the standardized values and values obtained from measurements made under precision laboratory conditions.

  17. An Intra-laboratory Investigation of On-wafer Measurement Reproducibility at Millimeter-wave Frequencies

    Clarke, R.G.; Li, C.; Ridler, N.M.
    Understanding the relative contribution of contact repeatability and overall reproducibility for on-wafer measurements provides useful insight into the significance of measurement comparisons. We report on an intra-laboratory investigation into contact repeatability and the variation that may be anticipated when measurements are reproduced in different laboratories using different equipment. We pay particular attention to the dispersion in measurement results arising from the use of on-wafer and off-wafer calibration. Experimental results are reported for measurements in the frequency range 140 GHz to 220 GHz, together with preliminary estimates of the repeatability limits for this type of measurement.

  18. Development of a Verification Technique for On-wafer Noise Figure Measurement Systems

    Wu, Aihua; Li, Chong; Sun, Jing; Wang, Yibang; Liu, Chen
    We present the development of a verification technique for on-wafer noise figure (NF) measurement systems. As the key element of the technique, a verification device consisting of a mismatched attenuator and a low noise amplifier (LNA) has been developed. The attenuator and the LNA are fabricated on two separate chips but joined with a bondwire. The verification procedure based on the device has also been developed and tested on an on-wafer vector network analyzer system with a noise measurement option across the frequency range from 2 GHz to 20 GHz. It has also been found that the bondwire contributes to...

  19. Formation of Ferroelectrically Defined Ag Nanoarray Patterns

    Damm, Signe; Carville, N. Craig; Manzo, Michele; Gallo, Katia; Lopez, S.; Keyes, Tia E.; Forster, Robert J.; Rodriguez, Brian J.; Rice, James H.
    In order to produce the most effective Ag nanoarrays for plasmon enhanced fluorescence and Raman scattering made using ferroelectric substrates, the optimum conditions for the creation of arrays must be identified. We study here Ag nanopattern arrays formed using ferroelectric lithography based on periodically proton exchanged (PPE) template methods. We examine different conditions in regard to deposition of Ag nanoparticles and analyze the plasmon enhanced signal from the resulting nanoarray. We apply FLIM (fluorescence lifetime imaging) to assess different Ag nanoarray preparation conditions on fluorescence emission from selected fluorphores. In addition, we apply Raman and luminescence spectroscopy with AFM (atomic...

  20. Optical Properties of Porphyrin: Graphene Oxide Composites

    Reddy, M. Harsha Vardhan; Al-Shammari, Rusul M.; Al-Attar, Nebras; Lopez, Sergio; Keyes, Tia E.; Rice, James H.
    In this work we aim to (via a non-invasive functionalization approach) tune and alter the intrinsic features of optically “transparent” graphene, by integrating water-soluble porphyrin aggregates. We explore the potential to combine porphyrin aggregates and graphene oxide to assess the advantages of such as a composite compared to the individual systems. We apply a range of optical spectroscopy methods including photo-absorption, fluorescence assess ground-state and excited state interactions. Our studies show that comparing resonant Raman scattering with optical transmission and fluorescence microscopy that the presence of influences the microscopic structures of the resulting composites.

Aviso de cookies: Usamos cookies propias y de terceros para mejorar nuestros servicios, para análisis estadístico y para mostrarle publicidad. Si continua navegando consideramos que acepta su uso en los términos establecidos en la Política de cookies.