839 resultados para MOVING-OBJECTS
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Most museums, libraries, and archives throughout the world have to deal with paper damaged by iron gall ink. For more than a decade international research has been devoted to the topic in an attempt to provide practical treatments for objects and formulate guidelines for the preservation of iron gall ink collections. A working group of conservators in South and Central America and the Caribbean have developed a program to disseminate research findings, collect data about the condition of iron gall ink collections in their countries and identify imminent training needs. The goal of this project is to combine the latest research with existing and acceptable conservation practices and share information about risk management, proper housing, examination and treatment of iron gall ink inscribed artefacts-at risk. Communications among colleagues were established to learn more about the current resources available in collections from various countries.
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Wet impregnation of pre-synthesized surfactant-stabilized aqueous rhodium (0) colloidal suspension on silica was employed in order to prepare supported Rh-0 nanoparticles of well-defined composition, morphology and size. A magnetic core-shell support of silica (Fe(3)O4@SiO2) was used to increase the handling properties of the obtained nanoheterogeneous catalyst. The nanocomposite catalyst Fe3O4@SiO2-Rh-0 NPs was highly active in the solventless hydrogenation of model olefins and aromatic substrates under mild conditions with turnover frequencies up to 143,000 h(-1). The catalyst was characterized by various transmission electron microscopy techniques showing well-dispersed rhodium nanoparticles (similar to 3 nm) mainly located at the periphery of the silica coating. The heterogeneous magnetite-supported nanocatalyst was investigated in the hydrogenation of cyclohexene and compared to the previous surfactant-stabilized aqueous Rh-0 colloidal suspension and various silica-supported Rh-0 nanoparticles. Finally, the composite catalyst could be reused in several runs after magnetic separation. (C) 2011 Elsevier B. V. All rights reserved.
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Discusses the technological changes that affects learning organizations as well as the human, technical, legal and sustainable aspects regarding learning objects repositories creation, maintenance and use. It presents concepts of information objects and learning objects, the functional requirements needed to their storage at Learning Management Systems. The role of Metadata is reviewed concerning learning objects creation and retrieval, followed by considerations about learning object repositories models, community participation/collaborative strategies and potential derived metrics/indicators. As a result of this desktop research, it can be said that not only technical competencies are critical to any learning objects repository implementation, but it urges that an engaged community of interest be establish as a key to support a learning object repository project. On that matter, researchers are applying Activity Theory (Vygostky, Luria y Leontiev) in order to seek joint perceptions and actions involving learning objects repository users, curators and managers, perceived as critical assets to a successful proposal.
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Experimental results of flow around a circular cylinder with moving surface boundary-layer control (MSBC) are presented. Two small rotating cylinders strategically located inject momentum in the boundary layer of the cylinder, which delays the separation of the boundary layer. As a consequence, the wake becomes narrower and the fluctuating transverse velocity is reduced, resulting in a recirculation free region that prevents the vortex formation. The control parameter is the ratio between the tangential velocity of the moving surface and the flow velocity (U-c/U). The main advantage of the MSBC is the possibility of combining the suppression of vortex-induced vibration (VIV) and drag reduction. The experimental tests are preformed at a circulating water channel facility and the circular cylinders are mounted on a low-damping air bearing base with one degree-of-freedom in the transverse direction of the channel flow. The mass ratio is 1.8. The Reynolds number ranges from 1600 to 7500, the reduced velocity varies up to 17, and the control parameter interval is U-c/U = 5-10. A significant decreasing in the maximum amplitude of oscillation for the cylinder with MSBC is observed. Drag measurements are obtained for statically mounted cylinders with and without MSBC. The use of the flow control results in a mean drag reduction at U-c/U = 5 of almost 60% compared to the plain cylinder. PIV velocity fields of the wake of static cylinders are measured at Re = 3000. The results show that the wake is highly organized and narrower compared to the one observed in cylinders without control. The calculation of the total variance of the fluctuating transverse velocity in the wake region allows the introduction of an active closed-loop control. The experimental results are in good agreement with the numerical simulation studies conducted by other researchers for cylinders with MSBC. (C) 2012 Elsevier Ltd. All rights reserved.
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Let D be a division ring with center k, and let D-dagger be its multiplicative group. We investigate the existence of free groups in D-dagger, and free algebras and free group algebras in D. We also go through the case when D has an involution * and consider the existence of free symmetric and unitary pairs in D-dagger.
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The present work propounds an inverse method to estimate the heat sources in the transient two-dimensional heat conduction problem in a rectangular domain with convective bounders. The non homogeneous partial differential equation (PDE) is solved using the Integral Transform Method. The test function for the heat generation term is obtained by the chip geometry and thermomechanical cutting. Then the heat generation term is estimated by the conjugated gradient method (CGM) with adjoint problem for parameter estimation. The experimental trials were organized to perform six different conditions to provide heat sources of different intensities. This method was compared with others in the literature and advantages are discussed. (C) 2012 Elsevier Ltd. All rights reserved.
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Context. Convergent point (CP) search methods are important tools for studying the kinematic properties of open clusters and young associations whose members share the same spatial motion. Aims. We present a new CP search strategy based on proper motion data. We test the new algorithm on synthetic data and compare it with previous versions of the CP search method. As an illustration and validation of the new method we also present an application to the Hyades open cluster and a comparison with independent results. Methods. The new algorithm rests on the idea of representing the stellar proper motions by great circles over the celestial sphere and visualizing their intersections as the CP of the moving group. The new strategy combines a maximum-likelihood analysis for simultaneously determining the CP and selecting the most likely group members and a minimization procedure that returns a refined CP position and its uncertainties. The method allows one to correct for internal motions within the group and takes into account that the stars in the group lie at different distances. Results. Based on Monte Carlo simulations, we find that the new CP search method in many cases returns a more precise solution than its previous versions. The new method is able to find and eliminate more field stars in the sample and is not biased towards distant stars. The CP solution for the Hyades open cluster is in excellent agreement with previous determinations.
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This paper presents the results of a simulation using physical objects. This concept integrates the physical dimensions of an entity such as length, width, and weight, with the usual process flow paradigm, recurrent in the discrete event simulation models. Based on a naval logistics system, we applied this technique in an access channel of the largest port of Latin America. This system is composed by vessel movement constrained by the access channel dimensions. Vessel length and width dictates whether it is safe or not to have one or two ships simultaneously. The success delivered by the methodology proposed was an accurate validation of the model, approximately 0.45% of deviation, when compared to real data. Additionally, the model supported the design of new terminals operations for Santos, delivering KPIs such as: canal utilization, queue time, berth utilization, and throughput capability
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Recent statistics have demonstrated that two of the most important causes of failures of the UAVs (Uninhabited Aerial Vehicle) missions are related to the low level of decisional autonomy of vehicles and to the man machine interface. Therefore, a relevant issue is to design a display/controls architecture which allows the efficient interaction between the operator and the remote vehicle and to develop a level of automation which allows the vehicle the decision about change in mission. The research presented in this paper focuses on a modular man-machine interface simulator for the UAV control, which simulates UAV missions, developed to experiment solution to this problem. The main components of the simulator are an advanced interface and a block defined automation, which comprehend an algorithm that implements the level of automation of the system. The simulator has been designed and developed following a user-centred design approach in order to take into account the operator’s needs in the communication with the vehicle. The level of automation has been developed following the supervisory control theory which says that the human became a supervisor who sends high level commands, such as part of mission, target, constraints, in then-rule, while the vehicle receives, comprehends and translates such commands into detailed action such as routes or action on the control system. In order to allow the vehicle to calculate and recalculate the safe and efficient route, in term of distance, time and fuel a 3D planning algorithm has been developed. It is based on considering UASs representative of real world systems as objects moving in a virtual environment (terrain, obstacles, and no fly zones) which replicates the airspace. Original obstacle avoidance strategies have been conceived in order to generate mission planes which are consistent with flight rules and with the vehicle performance constraints. The interface is based on a touch screen, used to send high level commands to the vehicle, and a 3D Virtual Display which provides a stereoscopic and augmented visualization of the complex scenario in which the vehicle operates. Furthermore, it is provided with an audio feedback message generator. Simulation tests have been conducted with pilot trainers to evaluate the reliability of the algorithm and the effectiveness and efficiency of the interface in supporting the operator in the supervision of an UAV mission. Results have revealed that the planning algorithm calculate very efficient routes in few seconds, an adequate level of workload is required to command the vehicle and that the 3D based interface provides the operator with a good sense of presence and enhances his awareness of the mission scenario and of the vehicle under his control.
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This study aims at analysing Brian O'Nolans literary production in the light of a reconsideration of the role played by his two most famous pseudonyms ,Flann Brien and Myles na Gopaleen, behind which he was active both as a novelist and as a journalist. We tried to establish a new kind of relationship between them and their empirical author following recent cultural and scientific surveys in the field of Humour Studies, Psychology, and Sociology: taking as a starting point the appreciation of the comic attitude in nature and in cultural history, we progressed through a short history of laughter and derision, followed by an overview on humour theories. After having established such a frame, we considered an integration of scientific studies in the field of laughter and humour as a base for our study scheme, in order to come to a definition of the comic author as a recognised, powerful and authoritative social figure who acts as a critic of conventions. The history of laughter and comic we briefly summarized, based on the one related by the French scholar Georges Minois in his work (Minois 2004), has been taken into account in the view that humorous attitude is one of manâs characteristic traits always present and witnessed throughout the ages, though subject in most cases to repression by cultural and political conservative power. This sort of Super-Ego notwithstanding, or perhaps because of that, comic impulse proved irreducible exactly in its influence on the current cultural debates. Basing mainly on Robert R. Provineâs (Provine 2001), Fabio Ceccarelliâs (Ceccarelli 1988), Arthur Koestlerâs (Koestler 1975) and Peter L. Bergerâs (Berger 1995) scientific essays on the actual occurrence of laughter and smile in complex social situations, we underlined the many evidences for how the use of comic, humour and wit (in a Freudian sense) could be best comprehended if seen as a common mind process designed for the improvement of knowledge, in which we traced a strict relation with the play-element the Dutch historian Huizinga highlighted in his famous essay, Homo Ludens (Huizinga 1955). We considered comic and humour/wit as different sides of the same coin, and showed how the demonstrations scientists provided on this particular subject are not conclusive, given that the mental processes could not still be irrefutably shown to be separated as regards graduations in comic expression and reception: in fact, different outputs in expressions might lead back to one and the same production process, following the general âEconomy Ruleâ of evolution; man is the only animal who lies, meaning with this that one feeling is not necessarily biuniquely associated with one and the same outward display, so human expressions are not validation proofs for feelings. Considering societies, we found that in nature they are all organized in more or less the same way, that is, in élites who govern over a community who, in turn, recognizes them as legitimate delegates for that task; we inferred from this the epistemological possibility for the existence of an added ruling figure alongside those political and religious: this figure being the comic, who is the person in charge of expressing true feelings towards given subjects of contention. Any community owns one, and his very peculiar status is validated by the fact that his place is within the community, living in it and speaking to it, but at the same time is outside it in the sense that his action focuses mainly on shedding light on ideas and objects placed out-side the boundaries of social convention: taboos, fears, sacred objects and finally culture are the favourite targets of the comic personâs arrow. This is the reason for the word a(rche)typical as applied to the comic figure in society: atypical in a sense, because unconventional and disrespectful of traditions, critical and never at ease with unblinkered respect of canons; archetypical, because the âvillage foolâ, buffoon, jester or anyone in any kind of society who plays such roles, is an archetype in the Jungian sense, i.e. a personification of an irreducible side of human nature that everybody instinctively knows: a beginner of a tradition, the perfect type, what is most conventional of all and therefore the exact opposite of an atypical. There is an intrinsic necessity, we think, of such figures in societies, just like politicians and priests, who should play an elitist role in order to guide and rule not for their own benefit but for the good of the community. We are not naïve and do know that actual owners of power always tend to keep it indefinitely: the âsocial comicâ as a role of power has nonetheless the distinctive feature of being the only job whose tension is not towards stability. It has got in itself the rewarding permission of contradiction, for the very reason we exposed before that the comic must cast an eye both inside and outside society and his vision may be perforce not consistent, then it is satisfactory for the popularity that gives amongst readers and audience. Finally, the difference between governors, priests and comic figures is the seriousness of the first two (fundamentally monologic) and the merry contradiction of the third (essentially dialogic). MPs, mayors, bishops and pastors should always console, comfort and soothe popular mood in respect of the public convention; the comic has the opposite task of provoking, urging and irritating, accomplishing at the same time a sort of control of the soothing powers of society, keepers of the righteousness. In this view, the comic person assumes a paramount importance in the counterbalancing of power administration, whether in form of acting in public places or in written pieces which could circulate for private reading. At this point comes into question our Irish writer Brian O'Nolan(1911-1966), real name that stood behind the more famous masks of Flann O'Brien, novelist, author of At Swim-Two-Birds (1939), The Hard Life (1961), The Dalkey Archive (1964) and, posthumously, The Third Policeman (1967); and of Myles na Gopaleen, journalist, keeper for more than 25 years of the Cruiskeen Lawn column on The Irish Times (1940-1966), and author of the famous book-parody in Irish An Béal Bocht (1941), later translated in English as The Poor Mouth (1973). Brian O'Nolan, professional senior civil servant of the Republic, has never seen recognized his authorship in literary studies, since all of them concentrated on his alter egos Flann, Myles and some others he used for minor contributions. So far as we are concerned, we think this is the first study which places the real name in the title, this way acknowledging him an unity of intents that no-one before did. And this choice in titling is not a mere mark of distinction for the sake of it, but also a wilful sign of how his opus should now be reconsidered. In effect, the aim of this study is exactly that of demonstrating how the empirical author Brian O'Nolan was the real Deus in machina, the master of puppets who skilfully directed all of his identities in planned directions, so as to completely fulfil the role of the comic figure we explained before. Flann O'Brien and Myles na Gopaleen were personae and not persons, but the impression one gets from the critical studies on them is the exact opposite. Literary consideration, that came only after O'Nolans death, began with Anne Clissmannâs work, Flann O'Brien: A Critical Introduction to His Writings (Clissmann 1975), while the most recent book is Keith Donohueâs The Irish Anatomist: A Study of Flann O'Brien (Donohue 2002); passing through M.Keith Bookerâs Flann O'Brien, Bakhtin and Menippean Satire (Booker 1995), Keith Hopperâs Flann O'Brien: A Portrait of the Artist as a Young Post-Modernist (Hopper 1995) and Monique Gallagherâs Flann O'Brien, Myles et les autres (Gallagher 1998). There have also been a couple of biographies, which incidentally somehow try to explain critical points his literary production, while many critical studies do the same on the opposite side, trying to found critical points of view on the authorâs restless life and habits. At this stage, we attempted to merge into O'Nolan's corpus the journalistic articles he wrote, more than 4,200, for roughly two million words in the 26-year-old running of the column. To justify this, we appealed to several considerations about the figure O'Nolan used as writer: Myles na Gopaleen (later simplified in na Gopaleen), who was the equivalent of the street artist or storyteller, speaking to his imaginary public and trying to involve it in his stories, quarrels and debates of all kinds. First of all, he relied much on language for the reactions he would obtain, playing on, and with, words so as to ironically unmask untrue relationships between words and things. Secondly, he pushed to the limit the convention of addressing to spectators and listeners usually employed in live performing, stretching its role in the written discourse to come to a greater effect of involvement of readers. Lastly, he profited much from what we labelled his âspecific weightâ, i.e. the potential influence in society given by his recognised authority in determined matters, a position from which he could launch deeper attacks on conventional beliefs, so complying with the duty of a comic we hypothesised before: that of criticising society even in threat of losing the benefits the post guarantees. That seemingly masochistic tendency has its rationale. Every representative has many privileges on the assumption that he, or she, has great responsibilities in administrating. The higher those responsibilities are, the higher is the reward but also the severer is the punishment for the misfits done while in charge. But we all know that not everybody accepts the rules and many try to use their power for their personal benefit and do not want to undergo lawâs penalties. The comic, showing in this case more civic sense than others, helped very much in this by the non-accessibility to the use of public force, finds in the role of the scapegoat the right accomplishment of his task, accepting the punishment when his breaking of the conventions is too stark to be forgiven. As Ceccarelli demonstrated, the role of the object of laughter (comic, ridicule) has its very own positive side: there is freedom of expression for the person, and at the same time integration in the society, even though at low levels. Then the banishment of a âsocialâ comic can never get to total extirpation from society, revealing how the scope of the comic lies on an entirely fictional layer, bearing no relation with facts, nor real consequences in terms of physical health. Myles na Gopaleen, mastering these three characteristics we postulated in the highest way, can be considered an author worth noting; and the oeuvre he wrote, the whole collection of Cruiskeen Lawn articles, is rightfully a novel because respects the canons of it especially regarding the authorial figure and his relationship with the readers. In addition, his work can be studied even if we cannot conduct our research on the whole of it, this proceeding being justified exactly because of the resemblances to the real figure of the storyteller: its âchaptersâ âthe daily articlesâ had a format that even the distracted reader could follow, even one who did not read each and every article before. So we can critically consider also a good part of them, as collected in the seven volumes published so far, with the addition of some others outside the collections, because completeness in this case is not at all a guarantee of a better precision in the assessment; on the contrary: examination of the totality of articles might let us consider him as a person and not a persona. Once cleared these points, we proceeded further in considering tout court the works of Brian O'Nolan as the works of a unique author, rather than complicating the references with many names which are none other than well-wrought sides of the same personality. By putting O'Nolan as the correct object of our research, empirical author of the works of the personae Flann O'Brien and Myles na Gopaleen, there comes out a clearer literary landscape: the comic author Brian O'Nolan, self-conscious of his paramount role in society as both a guide and a scourge, in a word as an a(rche)typical, intentionally chose to differentiate his personalities so as to create different perspectives in different fields of knowledge by using, in addition, different means of communication: novels and journalism. We finally compared the newly assessed author Brian O'Nolan with other great Irish comic writers in English, such as James Joyce (the one everybody named as the master in the field), Samuel Beckett, and Jonathan Swift. This comparison showed once more how O'Nolan is in no way inferior to these authors who, greatly celebrated by critics, have nonetheless failed to achieve that great public recognition OâNolan received alias Myles, awarded by the daily audience he reached and influenced with his Cruiskeen Lawn column. For this reason, we believe him to be representative of the comic figureâs function as a social regulator and as a builder of solidarity, such as that Raymond Williams spoke of in his work (Williams 1982), with in mind the aim of building a âculture in commonâ. There is no way for a âculture in commonâ to be acquired if we do not accept the fact that even the most functional society rests on conventions, and in a world more and more âconnectedâ we need someone to help everybody negotiate with different cultures and persons. The comic gives us a worldly perspective which is at the same time comfortable and distressing but in the end not harmful as the one furnished by politicians could be: he lets us peep into parallel worlds without moving too far from our armchair and, as a consequence, is the one who does his best for the improvement of our understanding of things.
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ABSTRACT In passato valeva il motto “grande è meglio”. Le aziende avevano enormi magazzini che riempivano fino a che questi riuscivano a contenere merce. Ciò avveniva nella convinzione che gli alti costi della gestione delle scorte sarebbero stati superati dalle vendite. Negli ultimi anni le aziende hanno però radicalmente cambiato il loro approccio alla gestione delle rimanenze: queste, vengono considerate un eccesso e i magazzini con elevate scorte vengono visti come un‟opportunità mancata e capitale sprecato. I produttori sono sempre più consapevoli della necessità di minimizzare l‟inventario e massimizzare la rotazione dei prodotti. In questo contesto si inseriscono le problematiche connesse alla gestione delle scorte, con particolare riferimento al fenomeno dello slow moving, espressione che indica tutti i materiali a lenta movimentazione stoccati a magazzino. Questi spesso rappresentano un importante onere finanziario per le aziende: si sostengono costi di immobilizzo del capitale, di stoccaggio del materiale oltre a quelli connessi al rischio di obsolescenza. Molto spesso si tende a trascurare il problema, fino a quando le dimensioni di quest‟ultimo si ingrandiscono al punto di diventare una priorità aziendale da cui si cerca una rapida soluzione. L‟elaborato presenta un preliminare studio di caso che ha costituito il punto di partenza per la progettazione di un action plan per la riduzione e lo smaltimento degli item obsoleti e a bassa movimentazione di una realtà aziendale italiana del settore metalmeccanico di cui si presentano anche i primi risultati dell‟implementazione. Dopo aver fornito una panoramica teorica sul ruolo e la gestione delle scorte, si passa ad analizzare il problema dello slow moving in una particolare realtà aziendale, la Biffi s.r.l. di Fiorenzuola d‟Arda (Piacenza), un‟ impresa che dal 1955 produce attuatori per valvole. Esaminato il mercato di riferimento, il tipo di prodotto e il processo di fabbricazione, si passa all‟as-is del magazzino. Attraverso tale analisi, vengono poste in risalto le problematiche legate all‟identificazione, classificazione e gestione dei codici slow moving. E‟ stato proprio lo studio di questi dati che ha posto le basi per lo sviluppo dell‟action plan per la razionalizzazione delle giacenze a magazzino. Nell‟ultima parte dell‟elaborato ho quindi descritto le azioni intraprese e presentato i risultati ottenuti, che hanno consentito risparmi significativi senza effettuare investimenti , ma semplicemente utilizzando al meglio le risorse già disponibili.
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A single picture provides a largely incomplete representation of the scene one is looking at. Usually it reproduces only a limited spatial portion of the scene according to the standpoint and the viewing angle, besides it contains only instantaneous information. Thus very little can be understood on the geometrical structure of the scene, the position and orientation of the observer with respect to it remaining also hard to guess. When multiple views, taken from different positions in space and time, observe the same scene, then a much deeper knowledge is potentially achievable. Understanding inter-views relations enables construction of a collective representation by fusing the information contained in every single image. Visual reconstruction methods confront with the formidable, and still unanswered, challenge of delivering a comprehensive representation of structure, motion and appearance of a scene from visual information. Multi-view visual reconstruction deals with the inference of relations among multiple views and the exploitation of revealed connections to attain the best possible representation. This thesis investigates novel methods and applications in the field of visual reconstruction from multiple views. Three main threads of research have been pursued: dense geometric reconstruction, camera pose reconstruction, sparse geometric reconstruction of deformable surfaces. Dense geometric reconstruction aims at delivering the appearance of a scene at every single point. The construction of a large panoramic image from a set of traditional pictures has been extensively studied in the context of image mosaicing techniques. An original algorithm for sequential registration suitable for real-time applications has been conceived. The integration of the algorithm into a visual surveillance system has lead to robust and efficient motion detection with Pan-Tilt-Zoom cameras. Moreover, an evaluation methodology for quantitatively assessing and comparing image mosaicing algorithms has been devised and made available to the community. Camera pose reconstruction deals with the recovery of the camera trajectory across an image sequence. A novel mosaic-based pose reconstruction algorithm has been conceived that exploit image-mosaics and traditional pose estimation algorithms to deliver more accurate estimates. An innovative markerless vision-based human-machine interface has also been proposed, so as to allow a user to interact with a gaming applications by moving a hand held consumer grade camera in unstructured environments. Finally, sparse geometric reconstruction refers to the computation of the coarse geometry of an object at few preset points. In this thesis, an innovative shape reconstruction algorithm for deformable objects has been designed. A cooperation with the Solar Impulse project allowed to deploy the algorithm in a very challenging real-world scenario, i.e. the accurate measurements of airplane wings deformations.