100 research outputs found
Author Correction: Multi-target mode of action of silver against Staphylococcus aureus endows it with capability to combat antibiotic resistance
No full textThe original version of this Article contained an error in the author affiliations. Affiliation 1 incorrectly read “Department of Chemistry, The University of Hong Kong, Hong Kong S.A.R., People’s Republic of China”. This has now been corrected to “Department of Chemistry, State Key Laboratory of Synthetic Chemistry, CAS-HKU Joint Laboratory of Metallomics on Health and Environment, The University of Hong Kong, Hong Kong S.A.R., People’s Republic of China”. in both the PDF and HTML versions of the Article.link_to_OA_fulltex
[Obra póstuma de Isabel de Borbón] [Material gráfico] : [frontispicio] / Ballester F.t
No full textInscripción: "OBRA PÓSTUMA DE S.A.R LA RERENISIMA SEÑORA DOÑA ISABEL DE BORBÓN" En la parte inferior "TU FOELIX AUSTRIA NUBE"Frontispicio de: Meditaciones christianas para un retiro espiritual que escribio S.A.R. la Serenisima Señora Doña Isabel de Borbón. Princesa de Parma... / Traducidas del francés por Don Joaquin Molés Presbyt. -- Madrid : Andres Ramirez, 1767 ; Después vuelve a imprimirse en: Meditaciones christianas para un retiro espiritual / Su autora... Isabel de Borbón... ; traducidas del francés por Joaquín Moles ; y a expensas de la Serenísima Señora... Luisa de Borbón. - 5ª ed. y 2ª en castellano. - En Madrid : por Pantaleón Aznar, Año 1771 ; y en Meditaciones christianas para un retiro espiritual / su authora ... D.A Isabel de Borbon Infanta de España ... ; traducidas por D. Joachin Móles ... -- Octava edicion, y quinta en castellano. -- Madrid : en la Imprenta y Libreria de D. Juan Blanques ... , 1794Páez. Repertorio..., 195-8 y 1411-
Design of RF Oscillators for Wireless Digital Transmitters
No full textCost reduction is one of the main driving forces for integration. As such, advanced CMOS technologies offer excellent digital functionality and high-density integration capabilities. Properties that persuade designers to exploit new digitally assisted approaches rather than following conventional analogue techniques. Using these new concepts, fully integrated transmitters that operate from baseband up to the pre-power amplifier (PA) stage entirely in the digital domain have become feasible. However, this imposes many coupling issues for different parts of the transceiver, such as the local oscillator. One of the primary building blocks of the transmitter is an oscillator and each modern digital transmitter has to have at least one oscillator, which normally has tough specifications imposed by the standard and transceiver architecture. This thesis focuses on the design of digitally controlled oscillators which could have excellent phase noise, very fine frequency resolution, small footprint and wide tuning range. Moreover, a simple yet an efficient architectural solution for the problem of local oscillator pulling, which will likely be the main cause degrading spectral purity of the TX output in multi radio SoCs has been proposed.Microelectronics & Computer EngineeringElectrical Engineering, Mathematics and Computer Scienc
An Exploratory Model to Investigate the Dynamics of the World Energy System: A Biophysical Economics Perspective
No full textEnergy is inherent part of our current life. No one can imagine living without it. It has changed the lifestyle of people and it will continue to do so in future. About 80% of current global total primary energy supply belongs to non-renewable resources. It is also expected that non-renewable resources dominate in total primary energy supply in next decades. The world is moving towards scarcity in non-renewable energy resources. Most studies about the world energy-economy system use standard economic theories. These theories do not include limitations of natural resources and the environment. Biophysical economics theory considers the relation between economy and natural resources. It has been used as the basis of various energy-economy models. However, those models have a global view on this system. They do not sufficiently provide insights into the properties and international trading behaviors of energy suppliers and consumers. So, they do not provide insight on the effects of these interactions on the emergent behavior of the global energy system. Biophysical economics has high potential for providing insights into the world energy system. However, the current biophysical models are not capable of representing the world energy system considering trade and other interactions among regions. Considering this problem the main research question in this thesis is stated as follow: What can be learnt from biophysical economics theory when it is used for the modeling of the world energy system considering energy trade? In order to answer this question, the objective of this research is set to develop a model for exploring the behaviors of the world energy system with multiple interacting regions. The theory of complex adaptive systems (CAS) is used to enable biophysical economics theory to consider trade and other interactions among regions. In order to model and analyze the world energy system from both biophysical economics and CAS perspective, agent-based modeling is identified as the most appropriate paradigm. This thesis provides an analysis of the world energy system from both technical and actor perspectives. The technical analysis aims at describing the main characteristics of and activities in the world energy system. It also identifies the main uncertainties within this system. Actor analysis aims at providing a regional decomposition for the world energy system. To achieve this goal, a number of current regional decompositions are identified. One of those is selected on the basis of a number of criteria. This research uses the 11-region decomposition of (IIASA, 2012b) To develop the objective model, a two-step approach is used. In the first step, the aggregated world energy model is developed without considering energy trade. In the second step, the multi-region world energy model is developed considering energy trade. The aggregated world energy model is the implementation of the most recent biophysical economics model in the literature, GEMBA by (M. A. J. Dale, 2010), in NetLogo. The multi-region model inherits all characteristics of the first model. However, it considers each world region as a world and facilitates the energy trade among them. The models are evaluated by comparison with historical data and literature. The multi-region model shows that the energy trade can be modeled and explored using the biophysical economics perspective. Since it includes energy price as a parameter, it also shows that energy trade can be an interface between biophysical economics and standard economics as well. In addition, exploratory experiments show that size of energy trade for regions is low in comparison to their total production/consumption. Moreover, they show that the size of total energy trade will peak and decline. It is because energy trade mostly belongs to non-renewable energy and the production of non-renewables will peak and decline in the future. In addition, it shows that lower energy trade can increase the share of production of energy.System Engineering, Policy Analysis and ManagementInfrastructure Systems & ServicesTechnology, Policy and Managemen
Analysis and Design of a Multi-Core Oscillator for Ultra-Low Phase Noise
No full textIn this paper, we exploit an idea of coupling multiple oscillators to reduce phase noise (PN) to beyond the limit of what has been practically achievable so far in a bulk CMOS technology. We then apply it to demonstrate for the first time an RF oscillator that meets the most stringent PN requirements of cellular basestation receivers while abiding by the process technology reliability rules. The oscillator is realized in digital 65-nm CMOS as a dualcore LC-tank oscillator based on a high-swing class-C topology. It is tunable within 4.07-4.91 GHz, while drawing 39-59 mA from a 2.15 V power supply. The measured PN is -146.7 dBc/Hz and -163.1 dBc/Hz at 3 MHz and 20 MHz offset, respectively, from a 4.07 GHz carrier, which makes it the lowest reported normalized PN of an integrated CMOS oscillator. Straightforward expressions for PN and interconnect resistance between the cores are derived and verified against circuit simulations and measurements. Analysis and simulations show that the interconnect resistance is not critical even with a 1% mismatch between the cores. This approach can be extended to a higher number of cores and achieve an arbitrary reduction in PN at the cost of the power and area
One dimensional electromagnetic waves on flat surfaces
No full textAuthor version of article. The version of record is available as an open access article from the publisher via doi: http://dx.doi.org/10.1088/0022-3727/47/43/435103© 2014 IOP Publishing LtdWe show that one-dimensional electromagnetic waves can be constrained to propagate along a join between two thin sheets when one surface supports transverse magnetic polarized surface waves and the other supports transverse electric polarized surface waves. We calculate the dispersion relation of these modes and show that they are exceptionally tightly confined to the join, with characteristic decay lengths an order of magnitude smaller than the surface waves supported by each individual surface. We give an example of a metasurface implementation where low frequency instances of such waves may be observed.Engineering and Physical Sciences Research Council (EPSRC
A Tiny Quadrature Oscillator Using Low-Q Series LC Tanks
No full textA new quadrature oscillator topology is proposed, which arranges four low-Q series LC tanks in a ring structure driven by inverters operating in class-D. With a very small area of 0.007 mm^2 that is comparable to conventional ring oscillators, this oscillator has 7–20 dB better phase noise FoM of 177 dB. It is widely tunable for nearly an octave from 2.66 to 4.97 GHz.MicroelectronicsElectrical Engineering, Mathematics and Computer Scienc
A new method for synthesizing test accuracy data outperformed the bivariate method
No full textObjectives: This study outlines the development of a new method (split component synthesis; SCS) for meta-analysis of diagnostic accuracy studies and assesses its performance against the commonly used bivariate random effects model. Methods: The SCS method summarizes the study-specific diagnostic odds ratio (on the ln(DOR) scale), which mainly reflects test discrimination rather than threshold effects, and then splits the summary ln(DOR) into its component parts, logit sensitivity (Se) and logit specificity (Sp). Performance of SCS estimator was assessed through simulation and compared against the bivariate random effects model estimator in terms of bias, mean squared error (MSE), and coverage probability across varying degrees of between-studies heterogeneity. Results: The SCS estimator for the DOR, Se, and Sp was less biased and had smaller MSE than the bivariate model estimator. Despite the wider width of the 95% confidence intervals under the bivariate model, the latter had a poorer coverage probability than that under the SCS method. Conclusion: The SCS estimator outperforms the bivariate model estimator and thus represents an improvement in the approach to diagnostic meta-analyses. The SCS method is available to researchers through the diagma module in Stata and the SCSmeta function in R. © 2020 The Author
Historical layering of straight streets in Macau [45].
No full text(1780, 1889, 1950, and 2018). Reprinted from [MNL.05.03. CART 1780] under a CC BY license with permission from [ARQUIVO DE MACAU], original copyright [1780]. Reprinted from [MNL.10.18h. CART 1889] under a CC BY license with permission from [ARQUIVO DE MACAU], original copyright [1889]. Reprinted from [MNL.05.26. CART 1950] under a CC BY license with permission from [ARQUIVO DE MACAU], original copyright [1950]. Reprinted from [https://viewer.nationalmap.gov/advanced-viewer/] under a CC BY license with permission from [USGS National Map Viewer], original copyright [2018]. Image source: The author selected the historical maps of 1780, 1889, 1950, and 2018 as the base maps for layering analysis and self-drawing. The base maps of 1780, 1889, and 1950 were obtained from the Archives of Macau, Cultural Affairs Bureau, Macau S.A.R. Government. The base map of 2018 was obtained from the USGS National Map Viewer. https://viewer.nationalmap.gov/advanced-viewer/.</p
- …
