24,039 research outputs found
James Stirling and the Tate Gallery Project in Albert Dock, Liverpool, 1982-88
El proyecto de James Stirling para adecuar el viejo almacén de Albert Dock para la Tate Gallery en Liverpool contenía
dos niveles de intervención. El primero afectó a la intervención en su interior, que el arquitecto pudo desarrollar, coincidiendo en el
tiempo con un momento de madurez personal y con el final de algunas obras claves de su trayectoria. Analizaremos las estrategias
que Stirling utilizó para organizar el programa museístico, poner en valor la herencia estructural del proyecto de Jesse Hartley, sin
renunciar a las mejores condiciones expositivas que la experiencia en el diseño de instalaciones similares le había permitido alcanzar.
El segundo nivel de intervención, cuya propuesta fue rechazada y no pudo realizar, contemplaba el proyecto de nuevos accesos
y conexiones con el viejo edificio. Fue una época en la que las autoridades estaban apostando por la readecuación y rehabilitación
de toda la zona de los docks, de la que Albert Dock era y es la joya de la corona. Analizaremos los contenidos gráficos y escritos del
irrealizado croquis de 1982 y veremos la aspiración de Stirling de vincular la visibilidad del museo con la propia historia de la ciudad
y la arqueología vital de su propia memoria, planteando estrategias formales que, aun estando presentes en parte en otras obras,
muestran una innovación que surge del diálogo con las arquitecturas y los paisajes preexistentes que sirven de soporte al proyecto.James Stirling’s project to adapt the abandoned Albert Dock warehouse for the Tate Gallery in Liverpool involved two
levels of action. The first affected the inside of the building, a task that the architect was able to complete, coinciding in time with his
personal maturity and with the completion of some key works in his career. We analyse the strategies Stirling used to organise the
museum project, showcasing the structural legacy of Jesse Hartley’s project without renouncing the best exhibition conditions that
his experience in designing similar premises had allowed him to reach. The second action level, one he could not bring to fruition
because the proposal was rejected, contemplated new entrances to and connections with the old building. It was an era in which
the authorities were focused on readapting and restoring the entire dock area, of which the Albert Dock was –and is– the crown
jewel. We analyse the drawings and notes for the unachieved 1982 proposal, which reveal Stirling’s aspiration of linking the visibility
of the museum with the city’s own history and the essential archaeology of his own memory. We can see how he formulated formal
strategies that, although partially present in other works, show an innovation that arises from the dialogue with the pre–existing
architectures and landscapes that anchor the project
Fair value on commons-based intellectual property assets: Lessons of an estimation over Linux kernel.
Open source describes practices in production and development that promote access to the end product's source materials, spreading development burden amongst individuals and companies. This model has resulted in a large and efficient ecosystem and unheralded software innovation, freely available to society. Open source methods are also increasingly being applied in other fields of endeavour, such as biotechnology or cultural production. But under financial reporting framework, general volunteer activity is not reflected on financial statements. As a result, there is not value of volunteer contributions and there is also no single source for cost estimates of how much it has taken to develop an open source technology. This volunteer activity encloses not only individuals but corporations developing and contributing open source products. Standard methodology for reporting open source asset valuation is needed and must include value creation from the perspective of the different stakeholders.FLOSS, commons, accounting standards, financial reporting
AGN spiral galaxies in groups: effects of bars
We explore properties of barred active spiral galaxies in groups selected
from the SDSS-DR7, with the aim of assessing the effects of bars on AGN and the
role of the high density environment. We identified barred active galaxies that
reside in groups from SDSS-DR7 group catalog. To provide a suitable
quantification of the effects of bars, a reliable control sample of unbarred
active galaxies in high density environments with similar redshift, magnitude,
morphology, and bulge size distributions was constructed. We found that the
fraction of barred AGN galaxies in groups (~ 38 %) is higher than those in the
total barred AGN sample ( ~ 28 %), indicating that AGN spiral galaxies in
groups are more likely to be barred than those in the field. We also found that
barred AGN galaxies are more concentrated towards the group centers than the
other unbarred AGN group members. In addition, barred AGN host galaxies show an
excess of population dominated by red colors suggesting that bars produce an
importanteffect on galaxy colors of AGN hosts. The host groups of the barred
AGN exhibit a larger fraction of red colors than the host groups of the
corresponding unbarred active galaxies. Color-magnitude relations of both host
groups of AGN differ significantly: the host group colors of barred active
galaxies display distributions spreading toward red populations, with respect
to the host groups of the unbarred AGN objects. Barred active galaxies show an
excess of nuclear activity compared to galaxies without bars. We found that
barred active galaxies located farther from the group-center have stronger
Lum[OIII]. Our findings suggest that the efficiency of bars to transport
material towards the more central regions of the AGN galaxies in high density
environments reveals an important dependence on the localization of objects
within the group and on the host group colors.Comment: 10 pages, 10 figures. Accepted for Astronomy & Astrophysic
Towards a collocation writing assistant for learners of Spanish
This paper describes the process followed in creating a tool aimed at helping learners produce collocations in Spanish. First we present the Diccionario de colocaciones del español (DiCE), an online collocation dictionary, which represents the first stage of this process. The following section focuses on the potential user of a collocation learning tool: we examine the usability problems DiCE presents in this respect, and explore the actual learner needs through a learner corpus study of collocation errors. Next, we review how collocation production problems of English language learners can be solved using a variety of electronic tools devised for that language. Finally, taking all the above into account, we present a new tool aimed at assisting learners of Spanish in writing texts, with particular attention being paid to the use of collocations in this language
Recommended from our members
The relationship of drug reimbursement with the price and the quality of pharmaceutical innovations
This paper studies the strategic interaction between pharmaceutical firms' pricing decisions and government agencies' reimbursement decisions which discriminate between patients by giving reimbursement rights to patients for whom the drug is most effective. We show that if the reimbursement decision preceeds the pricing decision, the agency only reimburses some patients if the private and public health benefits from the new drug diverge. That is, when (i) there are large externalities of consuming the drug and (ii) the difference in costs between the new drug and the alternative treatment is large. Alternatively, if the firm can commit to a price in advance of the reimbursement decision, we identify a strategic effect which implies that by committing to a high price ex ante, the firm can force a listing outcome and make the agency more willing to reimburse than in the absence of commitment
Cost of energy and mutual shadows in a two-axis tracking PV system
The performance improvement obtained from the use of trackers in a PV system cannot be separated from the higher requirement of land due to the mutual shadows between generators. Thus, the optimal choice of distances between trackers is a compromise between productivity and land use to minimize the cost of the energy produced by the PV system during its lifetime.
This paper develops a method for the estimation and optimization of the cost of energy function. It is built upon a set of equations to model the mutual shadows geometry and a procedure for the optimal choice of the wire cross-section. Several examples illustrate the use of the method with a particular PV system under different conditions of land and equipment costs.
This method is implemented using free software available as supplementary material
Exact and efficient calculation of Lagrange multipliers in constrained biological polymers: Proteins and nucleic acids as example cases
In order to accelerate molecular dynamics simulations, it is very common to
impose holonomic constraints on their hardest degrees of freedom. In this way,
the time step used to integrate the equations of motion can be increased, thus
allowing, in principle, to reach longer total simulation times. The imposition
of such constraints results in an aditional set of Nc equations (the equations
of constraint) and unknowns (their associated Lagrange multipliers), that must
be solved in one way or another at each time step of the dynamics. In this work
it is shown that, due to the essentially linear structure of typical biological
polymers, such as nucleic acids or proteins, the algebraic equations that need
to be solved involve a matrix which is banded if the constraints are indexed in
a clever way. This allows to obtain the Lagrange multipliers through a
non-iterative procedure, which can be considered exact up to machine precision,
and which takes O(Nc) operations, instead of the usual O(Nc3) for generic
molecular systems. We develop the formalism, and describe the appropriate
indexing for a number of model molecules and also for alkanes, proteins and
DNA. Finally, we provide a numerical example of the technique in a series of
polyalanine peptides of different lengths using the AMBER molecular dynamics
package.Comment: 29 pages, 10 figures, 1 tabl
A model for the simulation of energy gains when using distributed maximum power point tracking (DMPPT) in photovoltaic arrays
Over the past years, the photovoltaic (PV) market has been invaded with numerous power optimizers and micro-inverters that claim large energy gains when used in PV generators with shading or module mismatch. These products provide distributed maximum power point tracking (DMPPT), normally at module level, allowing the maximum power to be extracted from each PV module. This topology can be beneficial in situations where the PV generator is shaded or when there is large module mismatch. However, it is not clear that this power gain will result in energy improvements over a whole year or the lifetime of the system. This paper presents a very detailed and precise model for simulating energy gains with DMPPT as well as its verification and simulation results with different shading profiles, showing the possible energy gain over a whole year. Simulation results show that the yearly energy gain is much lower than the maximum power gain. However, interesting yearly gains of up to 12% are obtained in one of the simulations
Wind energy forecasting with neural networks: a literature review
Renewable energy is intermittent by nature and to integrate this energy into the Grid while assuring safety and stability the accurate forecasting of there newable energy generation is critical. Wind Energy prediction is based on the ability to forecast wind. There are many methods for wind forecasting based on the statistical properties of the wind time series and in the integration of meteorological information, these methods are being used commercially around the world. But one family of new methods for wind power fore castingis surging based on Machine Learning Deep Learning techniques. This paper analyses the characteristics of the Wind Speed time series data and performs a literature review of recently published works of wind power forecasting using Machine Learning approaches (neural and deep learning networks), which have been published in the last few years.Peer ReviewedPostprint (published version
- …