965 resultados para Master-builders


Relevância:

60.00% 60.00%

Publicador:

Resumo:

Aquesta tesi doctoral com diu el seu títol es centra en analitzar la construcció de l'església de Sant Feliu de Girona al segle XIV a través de l'anàlisi dels llibres d'obra conservats a l'Arxiu Diòcesa de Girona. Aquesta tesi doctoral esta dividida en quatre parts. En la primera part s'analitza la historiografia de l'església de Sant Feliu de Girona des del segle XVII fins a l'actualitat. Dins d'aquest apartat s'analitzen les notícies que aporten els diferents autors i es situa el context historiogràfic de cadascun dels segles. S'ha realitzat un estudi molt exhaustiu en les darreres publicacions del segle XX i inicis del segle XXI. Un cop analitzades aquestes fonts - secundàries -, dins d'aquesta primera part del treball s'ha passat a analitzar els llibres d'obra del segle XIV. S'analitzaràn els aspectes formals i els diferents escrivans encarregats de realitzar aquests llibres d'obra. Aquesta serà la documentació bàsica per realitzar aquesta tesi doctoral. En la segona part del treball es procedirà a analitzar la gestió i el finançament de l'Obra. Es tracta d'una anàlisi, bàsicament dels ingressos, per veure quines són les estratègies que es duen a terme per aconseguir el màxim de recursos per la construcció i per les necessitats "litúrgiques" de l'església de Sant Feliu de Girona. En aquest apartat s'ha analitzat l'Obra com a entitat amb les persones que formen part d'ella i el paper que correspon a cadascuna d'elles (l'obrer, l'escrivà, el mestre d'obres, el questor). També s'han analitzat els promotors i aquells ingressos que, pel seu volum, subministren el nombre més gran de diners a l'Obra ("annates", bacins, etc.). La tercera part ha consistit en l'elaboració de la cronologia constructiva de l'església de Sant Feliu de Girona partint de la informació obtinguda en els llibres d'obra corresponent a les despeses. S'han analitzat totes aquelles obres, tant pel que fa a la construcció de l'edifici com pel que fa a reparacions i manteniment, que tenen lloc entre l'any 1349 (data del primer llibre d'obra de despeses) i l'any 1391. En aquesta part no s'ha entrat a analitzar de forma exhaustiva les figures que fan possible la construcció de l'església al segle XIV ja que això pertany al contingut de la darrera part del nostre treball. La darrera part del treball correspon a l'execució de les obres. En aquesta part trobem quatre grans capítols: els mestres d'obra, la mà d'obra, els materials i els mitjans auxiliars. En cadascun d'aquests capítols s'ha incidit sobre el rol dels diferents treballadors durant la construcció del temple, els materials utilitzats i les seves característiques (pedra, fusta, aglomerants, etc.) i els mitjans auxiliars utilitzats per col.locar aquests materials en obra. S'han separat els mestres d'obres de la resta de treballadors ja que els primers juguen un rol diferenciat dels segons. S'ha intentat analitzar en ambdós casos els seus sous i les tasques de cadascun d'ells. Pel que fa als materials també s'ha procedit a analitzar d'on s'extreuen, com han arribat a peu d'obra i on s'emmagatzemen i manipulen o transformen abans d'ésser col.locats en obra. Dels mitjans auxiliars s'ha intentat analitzar les funcions per la qual es fan servir les eines (apareixen totes les de l'ofici de pedrer), els enginys (elevar pesos), les bastides (poder treballar en alçada) i el encofrats (garantir la resistència inicial dels elements constructius). Evidentment s'han establert unes conclusions de cadascuna de les parts i unes conclusions finals. La tesi també inclou els agraïments corresponents, el prefaci i la bibliografia.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

O texto versa sobre o papel dos mestres-construtores na produção da arquitetura nas vilas e cidades coloniais brasileiras, focalizando o sistema de empreitada em etapas e o papel dos riscos e traças na concepção, execução, louvação e prestação de contas das edificações. Questiona a ideia de autoria única, apontando atores e assinaturas múltiplas. Analisa os conhecimentos necessários, especialmente relacionados à geometria prática, discutindo a relação dialética entre teoria e prática, e as fronteiras tênues entre erudição e costume.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Plate-bandes are straight masonry arches (they are called, also, flat arches or lintel arches). Ideally they have the surfaces of extrados and intrados plane and horizontal. The stones or bricks have radial joints converging usually in one centre. The voussoirs have the form of wedges and in French they are called "claveaux". A plate-bande is, in fact, a lintel made of several stones and the proportions of lintels and plate-bandes are similar. Proportions of plate-bandes, that is the relationship between the thickness t and the span s (t/s)varies, typically between 1/4–1/3 in thick plate-bandes, and is less than 1/20 in the most slender ones. A ratio of circa 1/8 was usual in the 18th Century and follows a simple geometrical rule: the centre form with the intrados an equilateral triangle and the plate-bande should contain an arc of circle. The joints are usually plane, but in some cases present a «rebated» or «stepped» form. Plate-bandes exert an inclined thrust as any masonry arch. This thrust is usually very high and it requires either massive buttresses, or to be built in the middle of thick walls. Master builders and architects have tried since antiquity to calculate the abutment necessary for any arch. A modern architect or engineer will measure the arch thrust in units of force, kN or tons. Traditionally, the thrust has been measured as the size of the buttresses to resist it safely. Old structural rules, then, addressed the design problem establishing a relationship between the span and the depth of the buttress. These were empirical rules, particular for every type of arch or structure in every epoch. Thus, the typical gothic buttress is 1/4 of the vault span, but a Renaissance or baroque barrel vault will need more than 1/3 of the span. A plate-bande would require more than one half of the span; this is precisely the rule cited by the French engineer Gautier, who tried unsuccessfully to justify it by static reasons. They were used, typically, to form the lintels of windows or doors (1-2 m, typically); in Antiquity they were used, also, though rarely, at the gates of city walls or in niches (ca. 2 m, reaching 5.2 m). Plate-bandes may show particular problems: it is not unusual that some sliding of the voussoirs can be observed, particularly in thick plate-bandes. The stepped joints on Fig. 1, left, were used to avoid this problem. There are other «hidden» methods, like iron cramps or the use of stone wedges, etc. In seismic zones these devices were usual. Another problem relates to the deformation; a slight yielding of the abutments, or even the compression of the mortar joints, may lead to some cracking and the descent of the central keystone. Even a tiny descent will convert the original straight line of the intrados in a broken line with a visible «kink» or angle in the middle. Of course, both problems should be avoided. Finally, the wedge form of the voussoirs lead to acute angles in the stones and this can produce partial fractures; this occurs usually at the inferior border of the springers at the abutments. It follows, that to build a successful plate-bande is not an easy matter. Also, the structural study of plate-bandes is far from simple, and mechanics and geometry are related in a particular way. In the present paper we will concentrate on the structural aspects and their constructive consequences, with a historical approach. We will outline the development of structural analysis of plate-bandes from ca. 1700 until today. This brief history has a more than purely academic interest. Different approaches and theories pointed to particular problem, and though the solution given may have been incorrect, the question posed was often pertinent. The paper ends with the application of modern Limit Analysis of Masonry Structures, developed mainly by professor Heyman in the last fifty years. The work aims, also, to give some clues for the actual architect and engineer involved in the analysis or restoration of masonry buildings.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Unlike their counterparts in Europe and America, the citizen organizations acting for the well-being of animals in Japan have not received scholarly attention. In this research, I explore the activities of twelve Japanese pro-animal organizations in Tokyo and Kansai area from the perspective of social movement and civil society studies. The concept of a ‘pro-animal organization’ is used to refer generally to the collectives promoting animal well-being. By using the collective action frame analysis and the three core framing tasks – diagnostic, prognostic, and motivational – as the primarily analytical tools, I explore the grievances, tactics, motivational means, constructions of agency and identity as well as framing of civil society articulated in the newsletters and the interviews of the twelve organizations I interviewed in Japan in 2010. As the frame construction is always done in relation to the social and political context, I study how the organizations construct their roles as civil society actors in relation to other actors, such as the state, and the idea of citizen activism. The deficiencies in the animal welfare law and lack of knowledge among the public are identified as the main grievances. The primary tactic to overcome these problems was to educate and inform the citizens and authorities, because most organizations lack the channels to influence politically. The audiences were mostly portrayed as either ignorant bystanders or potential adherents. In order to motivate people to join their cause and to enforce the motivation within the organization, the organizations emphasized their uniqueness, proved their efficiency, claimed credit and celebrated even small improvements. The organizations tended to create three different roles for citizen pro-organizations in civil society: reactive, apolitical and emphatic animal lovers concentrating on saving individual animals, proactive, educative bridge-builders seeking to establish equal collaborative relations with authorities, and corrective, supervising watchdogs demanding change in delinquencies offending animal rights. Based on the results of this research, I suggest that by studying how and why the different relations between civil society and the governing actors of the state are constructed, a more versatile approach to citizens’ activism in its context can be achieved.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

In 1906, two American industrialists, John Munroe Longyear and Frederick Ayer, formed the Arctic Coal Company to make the first large scale attempt at mining in the high-Arctic location of Spitsbergen, north of the Norwegian mainland. In doing so, they encountered numerous obstacles and built an organization that attempted to overcome them. The Americans sold out in 1916 but others followed, eventually culminating in the transformation of a largely underdeveloped landscape into a mining region. This work uses John Law’s network approach of the Actor Network Theory (ANT) framework to explain how the Arctic Coal Company built a mining network in this environmentally difficult region and why they made the choices they did. It does so by identifying and analyzing the problems the company encountered and the strategies they used to overcome them by focusing on three major components of the operations; the company’s four land claims, its technical system and its main settlement, Longyear City. Extensive comparison between aspects of Longyear City and the company’s choices of technology with other American examples place analysis of the company in a wider context and helps isolate unique aspects of mining in the high-Arctic. American examples dominate comparative sections because Americans dominated the ownership and upper management of the company.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The 2d ed., 1884, was reprinted in 1888; the 3d ed., 1895, reprinted in 1898.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A combination of trajectory sensitivity method and master-slave synchronization was proposed to parameter estimation of nonlinear systems. It was shown that master-slave coupling increases the robustness of the trajectory sensitivity algorithm with respect to the initial guess of parameters. Since synchronization is not a guarantee that the estimation process converges to the correct parameters, a conditional test that guarantees that the new combined methodology estimates the true values of parameters was proposed. This conditional test was successfully applied to Lorenz's and Chua's systems, and the proposed parameter estimation algorithm has shown to be very robust with respect to parameter initial guesses and measurement noise for these examples. Copyright (C) 2009 Elmer P. T. Cari et al.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We present a derivation of the Redfield formalism for treating the dissipative dynamics of a time-dependent quantum system coupled to a classical environment. We compare such a formalism with the master equation approach where the environments are treated quantum mechanically. Focusing on a time-dependent spin-1/2 system we demonstrate the equivalence between both approaches by showing that they lead to the same Bloch equations and, as a consequence, to the same characteristic times T(1) and T(2) (associated with the longitudinal and transverse relaxations, respectively). These characteristic times are shown to be related to the operator-sum representation and the equivalent phenomenological-operator approach. Finally, we present a protocol to circumvent the decoherence processes due to the loss of energy (and thus, associated with T(1)). To this end, we simply associate the time dependence of the quantum system to an easily achieved modulated frequency. A possible implementation of the protocol is also proposed in the context of nuclear magnetic resonance.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

One-way master-slave (OWMS) chain networks are widely used in clock distribution systems due to their reliability and low cost. As the network nodes are phase-locked loops (PLLs), double-frequency jitter (DFJ) caused by their phase detectors appears as an impairment to the performance of the clock recovering process found in communication systems and instrumentation applications. A nonlinear model for OWMS chain networks with P + 1 order PLLs as slave nodes is presented, considering the DFJ. Since higher order filters are more effective in filtering DFJ, the synchronous state stability conditions for an OWMS chain network with third-order nodes are derived, relating the loop gain and the filter coefficients. By using these conditions, design examples are discussed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Clock signal distribution in telecommunication commercial systems usually adopts a master-slave architecture, with a precise time basis generator as a master and phase-locked loops (PLLs) as slaves. In the majority of the networks, second-order PLLs are adopted due to their simplicity and stability. Nevertheless, in some applications better transient responses are necessary and, consequently, greater order PLLs need to be used, in spite of the possibility of bifurcations and chaotic attractors. Here a master-slave network with third-order PLLs is analyzed and conditions for the stability of the synchronous state are derived, providing design constraints for the node parameters, in order to guarantee stability and reachability of the synchronous state for the whole network. Numerical simulations are carried out in order to confirm the analytical results. (C) 2009 Elsevier B.V. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The distribution of clock signals throughout the nodes of a network is essential for several applications. in control and communication with the phase-locked loop (PLL) being the component for electronic synchronization process. In systems with master-slave (MS) strategies, the PLLs are the slave nodes responsible for providing reliable clocks in all nodes of the network. As PLLs have nonlinear phase detection, double-frequency terms appear and filtering becomes necessary. Imperfections in filtering process cause oscillations around the synchronous state worsening the performance of the clock distribution process. The behavior of one-way master-slave (OWMS) clock distribution networks is studied and performances of first- and second-order filter processes are compared, concerning lock-in ranges and responses to perturbations of the synchronous state. (c) 2007 Elsevier GmbH. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The double-frequency jitter is one of the main problems in clock distribution networks. In previous works, sonic analytical and numerical aspects of this phenomenon were studied and results were obtained for one-way master-slave (OWMS) architectures. Here, an experimental apparatus is implemented, allowing to measure the power of the double-frequency signal and to confirm the theoretical conjectures. (C) 2008 Elsevier B.V. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A reversible linear master equation model is presented for pressure- and temperature-dependent bimolecular reactions proceeding via multiple long-lived intermediates. This kinetic treatment, which applies when the reactions are measured under pseudo-first-order conditions, facilitates accurate and efficient simulation of the time dependence of the populations of reactants, intermediate species and products. Detailed exploratory calculations have been carried out to demonstrate the capabilities of the approach, with applications to the bimolecular association reaction C3H6 + H reversible arrow C3H7 and the bimolecular chemical activation reaction C2H2 +(CH2)-C-1--> C3H3+H. The efficiency of the method can be dramatically enhanced through use of a diffusion approximation to the master equation, and a methodology for exploiting the sparse structure of the resulting rate matrix is established.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The Multicenter Australian Study of Epidural Anesthesia and Analgesia in Major Surgery (The MASTER Trial) was designed to evaluate the possible benefit of epidural block in improving outcome in high-risk patients. The trial began in 1995 and is scheduled to reach the planned sample size of 900 during 2001. This paper describes the trial design and presents data comparing 455 patients randomized in 21 institutions in Australia, Hong Kong, and Malaysia, with 237 patients from the same hospitals who were eligible but not randomized. Nine categories of high-risk patients were defined as entry criteria for the trial. Protocols for ethical review, informed consent, randomization, clinical anesthesia and analgesia, and perioperative management were determined following extensive consultation with anesthesiologists throughout Australia. Clinical and research information was collected in participating hospitals by research staff who may not have been blind to allocation. Decisions about the presence or absence of endpoints were made primarily by a computer algorithm, supplemented by blinded clinical experts. Without unblinding the trial, comparison of eligibility criteria and incidence of endpoints between randomized and nonrandomized patients showed only small differences. We conclude that there is no strong evidence of important demographic or clinical differences between randomized and nonrandomized patients eligible for the MASTER Trial. Thus, the trial results are likely to be broadly generalizable. Control Clin Trials 2000;21:244-256 (C) Elsevier Science Inc. 2000.