Gli oggetti e la documentazione degli scavi britannici di karkemish: Una nuova analisi

Questa tesi comprende la ricerca sui materiali provenienti dagli scavi britannici, avvenuti fra il 1911 e il 1920, del sito di Karkemish (Gaziantep - Turchia). Vengono qui studiati gli oggetti (a eccezione delle sculture) databili all’Età del Bronzo e del Ferro, che sono nella quasi totalità inediti. Si sono prese in considerazione i reperti attualmente conservati al British Museum di Londra, nei Musei Archeologici di Istanbul e al Museo delle Civiltà Anatoliche di Ankara.

La casa ellenistica in Epiro ed Illiria meridionale

Il ritrovamento della Casa dei due peristili a Phoinike ha aperto la strada a un’intensa opera di revisione di tutti i dati relativi all’edilizia domestica nella regione, con studi comparativi verso nord (Illiria meridionale) e verso sud (il resto dell’Epiro, ovvero Tesprozia e Molossia). Tutta quest’area della Grecia nord-occidentale è stata caratterizzata nell’antichità da un’urbanizzazione scarsa numericamente e tardiva cronologicamente (non prima del IV sec. a.C.), a parte ovviamente le colonie corinzio-corciresi di area Adriatico- Ionica d’età arcaica (come Ambracia, Apollonia, Epidamnos). A un’urbanistica di tipo razionale e programmato (ad es. Cassope, Orraon, Gitani in Tesprozia, Antigonea in Caonia) si associano numerosi casi di abitati cresciuti soprattutto in rapporto alla natura del suolo, spesso diseguale e montagnoso (ad es. Dymokastro/Elina in Tesprozia, Çuka e Aitoit nella Kestrine), talora semplici villaggi fortificati, privi di una vera fisionomia urbana. D’altro canto il concetto classico di polis così come lo impieghiamo normalmente per la Grecia centro-meridionale non ha valore qui, in uno stato di tipo federale e dominato dall’economia del pascolo e della selva. In questo contesto l’edilizia domestica assume caratteri differenti fra IV e I sec. a.C.: da un lato le città ortogonali ripetono schemi egualitari con poche eccezioni, soprattutto alle origini (IV sec. a.C., come a Cassope e forse a Gitani), dall’altro si delinea una spiccata differenziazione a partire dal III sec., quando si adottano modelli architettonici differenti, come i peristili, indizio di una più forte differenziazione sociale (esemplari i casi di Antigonea e anche di Byllis in Illiria meridionale). I centri minori e fortificati d’altura impiegano formule abitative più semplici, che sfruttano l’articolazione del terreno roccioso per realizzare abitazioni a quote differenti, utilizzando la roccia naturale anche come pareti o pavimenti dei vani.

Integrazione delle immagini ecotomografiche nei sistemi per chirurgia robotica: Stato dell'arte e sviluppi futuri

L'elaborato si propone di analizzare la fusione di due tecnologie diverse, ma allo stesso modo rivoluzionarie. Da un lato abbiamo la chirurgia robotica (Robotic Assisted Surgery), reputata ormai la nuova frontiera della chirurgia mini-invasiva, dall'altro invece l'eco-tomografia, che in molti ipotizzano poter divenire lo 'stetoscopio' del futuro.

Soil-structure interaction during tunnelling in urban area: observations and 3D numerical modelling

This work illustrates a soil-tunnel-structure interaction study performed by an integrated,geotechnical and structural,approach based on 3D finite element analyses and validated against experimental observations.The study aims at analysing the response of reinforced concrete framed buildings on discrete foundations in interaction with metro lines.It refers to the case of the twin tunnels of the Milan (Italy) metro line 5,recently built in coarse grained materials using EPB machines,for which subsidence measurements collected along ground and building sections during tunnelling were available.Settlements measured under freefield conditions are firstly back interpreted using Gaussian empirical predictions. Then,the in situ measurements’ analysis is extended to include the evolving response of a 9 storey reinforced concrete building while being undercrossed by the metro line.In the finite element study,the soil mechanical behaviour is described using an advanced constitutive model. This latter,when combined with a proper simulation of the excavation process, proves to realistically reproduce the subsidence profiles under free field conditions and to capture the interaction phenomena occurring between the twin tunnels during the excavation. Furthermore, when the numerical model is extended to include the building, schematised in a detailed manner, the results are in good agreement with the monitoring data for different stages of the twin tunnelling. Thus, they indirectly confirm the satisfactory performance of the adopted numerical approach which also allows a direct evaluation of the structural response as an outcome of the analysis. Further analyses are also carried out modelling the building with different levels of detail. The results highlight that, in this case, the simplified approach based on the equivalent plate schematisation is inadequate to capture the real tunnelling induced displacement field. The overall behaviour of the system proves to be mainly influenced by the buried portion of the building which plays an essential role in the interaction mechanism, due to its high stiffness.

Feedback linearization of antagonistically actuated variable stiffness joints with twisted string actuators

The work of this thesis is on the implementation of a variable stiffness joint antagonistically actuated by a couple of twisted-string actuator (TSA). This type of joint is possible to be applied in the field of robotics, like UB Hand IV (the anthropomorphic robotic hand developed by University of Bologna). The purposes of the activities are to build the joint dynamic model and simultaneously control the position and stiffness. Three different control approaches (Feedback linearization, PID, PID+Feedforward) are proposed and validated in simulation. To improve the properties of joint stiffness, a joint with elastic element is taken into account and discussed. To the end, the experimental setup that has been developed for the experimental validation of the proposed control approaches.

Methoden zur Analyse, Interpretation und Modellierung des elektrischen Widerstandes von archäologischen Steinstrukturen

In der Archäologie werden elektrische Widerstandsmessungen routinemäßig zur Prospektion von Fundstellen eingesetzt. Die Methode ist kostengünstig, leicht anwendbar und liefert in den meisten Fällen zuverlässige und leicht zu interpretierende Ergebnisse. Dennoch kann die Methode die archäologischen Strukturen in manchen Fällen nur teilweise oder gar nicht abbilden, wenn die bodenphysikalischen und bodenchemischen Eigenschaften des Bodens und der archäologischen Strukturen dies nicht zulassen. Der spezifische elektrische Widerstand wird durch Parameter wie Wassergehalt, Bodenstruktur, Bodenskelett, Bodentextur, Salinität und Bodentemperatur beeinflusst. Manche dieser Parameter, wie z.B. der Wassergehalt und die Bodentemperatur, unterliegen einer saisonalen Veränderung. Die vorliegende Arbeit untersucht den spezifischen elektrischen Widerstand von archäologischen Steinstrukturen und evaluiert die Möglichkeit, auf Grundlage von Geländemessungen und Laboranalysen archäologische Strukturen und Böden als numerische Modelle darzustellen. Dazu wurde eine Kombination von verschiedenen bodenkundlichen, geoarchäologischen und geophysikalischen Methoden verwendet. Um archäologische Strukturen und Bodenprofile als numerische Widerstandsmodelle darstellen zu können, werden Informationen zur Geometrie der Strukturen und ihren elektrischen Widerstandswerten benötigt. Dabei ist die Qualität der Hintergrundinformationen entscheidend für die Genauigkeit des Widerstandsmodells. Die Geometrie der Widerstandsmodelle basiert auf den Ergebnissen von Rammkernsondierungen und archäologische Ausgrabungen. Die an der Ausbildung des elektrischen Widerstands beteiligten Parameter wurden durch die Analyse von Bodenproben gemessen und ermöglichen durch Pedotransfer-Funktion, wie die Rhoades-Formel, die Abschätzung des spezifischen elektrischen Widerstandes des Feinbodens. Um den Einfluss des Bodenskeletts auf den spezifischen elektrischen Widerstand von Bodenprofilen und archäologischen Strukturen zu berechnen, kamen die Perkolationstheorie und die Effective Medium Theory zum Einsatz. Die Genauigkeit und eventuelle Limitierungen der Methoden wurden im Labor durch experimentelle Widerstandsmessungen an ungestörten Bodenproben und synthetischen Materialien überprüft. Die saisonale Veränderung des Wassergehalts im Boden wurde durch numerische Modelle mit der Software HYDRUS simuliert. Die hydraulischen Modelle wurden auf Grundlage der ermittelten bodenkundlichen und archäologischen Stratigraphie erstellt und verwenden die Daten von lokalen Wetterstationen als Eingangsparameter. Durch die Kombination der HYDRUS-Ergebnisse mit den Pedotransfer-Funktionen konnte der Einfluss dieser saisonalen Veränderung auf die Prospektionsergebnisse von elektrischen Widerstandsmethoden berechnet werden. Die Ergebnisse der Modellierungsprozesse wurden mit den Geländemessungen verglichen. Die beste Übereinstimmung zwischen Modellergebnissen und den Prospektionsergebnissen konnte für die Fallstudie bei Katzenbach festgestellt werden. Bei dieser wurden die Modelle auf Grundlage von archäologischen Grabungsergebnissen und detaillierten bodenkundlichen Analysen erstellt. Weitere Fallstudien zeigen, dass elektrische Widerstandsmodelle eingesetzt werden können, um den Einfluss von ungünstigen Prospektionsbedingungen auf die Ergebnisse der elektrischen Widerstandsmessungen abzuschätzen. Diese Informationen unterstützen die Planung und Anwendung der Methoden im Gelände und ermöglichen eine effektivere Interpretation der Prospektionsergebnisse. Die präsentierten Modellierungsansätze benötigen eine weitere Verifizierung durch den Vergleich der Modellierungsergebnisse mit detailliertem geophysikalischem Gelände-Monitoring von archäologischen Fundstellen. Zusätzlich könnten elektrische Widerstandsmessungen an künstlichen Mauerstrukturen unter kontrollierten Bedingungen zur Überprüfung der Modellierungsprozesse genutzt werden.

Untersuchung von Einflussfaktoren zur Ortsbruststabilität und Vortriebsgeschwindigkeit beim Tunnelbau im Rheinischen Schiefergebirge

Zusammenfassung Der ca. 1.555 m lange Tunnel Fernthal wurde von 1998 bis 2000 im Zuge der Bundesbahn-Neubaustrecke Köln – Rhein/Main erstellt. Der Tunnel durchquert devonische Schichten des Rechtsrheinischen Schiefergebirges. Die Ton- und Sandsteine sind tiefgründig verwittert, intensiv verfaltet mit wechselnden Vergenzen der Faltenschenkel und zudem stark durch Trennflächen zerlegt. Beim Auffahren des Tunnel Fernthal sind Phänomene in Bezug auf die Wechselwirkung zwischen dem Grundwasser und dem Tunnel sowie dem Fels und dem Tunnel beobachtet worden, die vom Verfasser der vorliegenden Arbeit im Nachgang der Baumaßnahme vertieft ausgewertet und interpretiert werden.Innerhalb von zwanzig strukturgeologischen Homogenbereichen wurden die geotechnisch und strukturgeologisch bestimmenden Einflussfaktoren (z.B. ungünstig zum Hohlraum einfallende Schichtung oder Querklüftung mit hohem Durchtrennungsgrad) im Hinblick auf Ihre Auswirkung auf die Sicherung der Ortsbrust und damit die Vortriebsgeschwindigkeit quantifiziert. Über das Produkt der den Vortrieb bestimmenden Einzelfaktoren wurde für den jeweiligen Homogenbereich ein Gesamteinflussfaktor errechnet.Aus dem neu eingeführten Gesamteinflussfaktors fn gesamt lassen sich dabei Empfehlungen über die notwendigen Sicherungsmaßnahmen im Bereich der Ortsbrust ableiten und Einteilungen in Ausbruchsklassen vornehmen. Über die Bewertungsmatrix und den sich daraus ergebenen Gesamteinflussfaktor können reduzierte Vortriebsgeschwindigkeiten ausgehend von einer 'idealen' Vortriebsgeschwindigkeit näherungsweise errechnet werden. Mithilfe der Bewertungsmatrix lässt sich die bautechnischen Eigenschaften des Gebirges besser bewerten. So zeigt sich im Rahmen dieser Arbeit deutlich, dass es bei einem vergenten Faltengebirge günstiger ist, den Tunnel gegen die Vergenz von Faltenschenkeln aufzufahren. Somit können schon im Vorfeld einer Tunnelbaumaßnahme verschiedene Vortriebsschemata durchrechnet werden. Neben der besseren Prognose von notwendigen Sicherungsmaßnahmen kann durch den Zeitgewinn auch ein finanzieller Vorteil für die Beteiligten entstehen.

La piattaforma ros per lo sviluppo di applicazioni robotiche

Lo sviluppo hardware nel campo della robotica ha raggiunto negli ultimi anni livelli impressionanti ed è in continua crescita, e di pari passo si è espansa l’eterogeneità delle forme che può assumere, dalle tipologie basate su movimento a terra ai droni volanti, fino a forme più sofisticate di robot umanoidi che cercano di emularne il comportamento. Se da un lato ora possiamo disporre di hardware sempre più potente ed efficiente a costi sempre minori, dall’altro programmare il comportamento che un robot deve tenere nelle svariate circostanze in cui può imbattersi, nel poter portare a compimento il proprio obbiettivo, risulta essere sempre più complesso. Dopo una breve introduzione alla robotica e alle difficoltà che deve affrontare e una panoramica sui robot, cosa siano e come siano strutturati, fulcro della tesi sarà l’esposizione delle caratteristiche principali di ROS, Robot Operating System, come piattaforma di sviluppo software nel campo della robotica, e si concluderà con un semplice caso di studio in cui ne verrà messo in mostra concretamente l’utilizzo.

Removal of enamel caries with an air abrasion powder

This study compared the efficiency of air abrasion on enamel caries with selective enamel powder (SEP) or with alumina powder and a negative and positive control group. Ninety-three extracted molars with non-cavitated incipient enamel lesions were selected. After embedding the roots in resin, each lesion was sectioned perpendicular to the surface and photographed. Each lesion was classified microscopically as having or not having dentin involvement. The lesions were distributed into four groups with an equal number of enamel caries with or without dentin involvement. Each group was treated differently: Group 1 had SEP abrasion, Group 2 had alumina abrasion, Group 3 had sodium bicarbonate abrasion (negative control) and Group 4 had bur treatment (positive control). The surface was rephotographed after treatment. Superimposition of the photographs identified areas of "correct-excavation," "under-excavation" and "over-excavation." There were no statistical differences between lesions treated with or without dentin involvement for Groups 2 through 4. However, in the SEP group, all measured areas were significantly influenced by dentin involvement. In pairwise comparisons, no statistical differences were found between the alumina and bur groups. The SEP group, however, showed statistically significant differences for each area compared to the alumina group in enamel caries without dentin involvement. SEP performed as well as alumina and bur in lesions with dentin involvement. SEP is different in its ablative properties toward caries with dentin involvement or no dentin involvement. In terms of dental treatment, SEP seems to have a diagnostic potential for enamel lesions before operative intervention in patients with high caries risk.

Retraining of interjoint arm coordination after stroke using robot-assisted time-independent functional training

We have developed a haptic-based approach for retraining of interjoint coordination following stroke called time-independent functional training (TIFT) and implemented this mode in the ARMin III robotic exoskeleton. The ARMin III robot was developed by Drs. Robert Riener and Tobias Nef at the Swiss Federal Institute of Technology Zurich (Eidgenossische Technische Hochschule Zurich, or ETH Zurich), in Zurich, Switzerland. In the TIFT mode, the robot maintains arm movements within the proper kinematic trajectory via haptic walls at each joint. These arm movements focus training of interjoint coordination with highly intuitive real-time feedback of performance; arm movements advance within the trajectory only if their movement coordination is correct. In initial testing, 37 nondisabled subjects received a single session of learning of a complex pattern. Subjects were randomized to TIFT or visual demonstration or moved along with the robot as it moved though the pattern (time-dependent [TD] training). We examined visual demonstration to separate the effects of action observation on motor learning from the effects of the two haptic guidance methods. During these training trials, TIFT subjects reduced error and interaction forces between the robot and arm, while TD subject performance did not change. All groups showed significant learning of the trajectory during unassisted recall trials, but we observed no difference in learning between groups, possibly because this learning task is dominated by vision. Further testing in stroke populations is warranted.

Validation of a modified AVHRR aerosol optical depth retrieval algorithm over Central Europe

The Advanced Very High Resolution Radiometer (AVHRR) carried on board the National Oceanic and Atmospheric Administration (NOAA) and the Meteorological Operational Satellite (MetOp) polar orbiting satellites is the only instrument offering more than 25 years of satellite data to analyse aerosols on a daily basis. The present study assessed a modified AVHRR aerosol optical depth τa retrieval over land for Europe. The algorithm might also be applied to other parts of the world with similar surface characteristics like Europe, only the aerosol properties would have to be adapted to a new region. The initial approach used a relationship between Sun photometer measurements from the Aerosol Robotic Network (AERONET) and the satellite data to post-process the retrieved τa. Herein a quasi-stand-alone procedure, which is more suitable for the pre-AERONET era, is presented. In addition, the estimation of surface reflectance, the aerosol model, and other processing steps have been adapted. The method's cross-platform applicability was tested by validating τa from NOAA-17 and NOAA-18 AVHRR at 15 AERONET sites in Central Europe (40.5° N–50° N, 0° E–17° E) from August 2005 to December 2007. Furthermore, the accuracy of the AVHRR retrieval was related to products from two newer instruments, the Medium Resolution Imaging Spectrometer (MERIS) on board the Environmental Satellite (ENVISAT) and the Moderate Resolution Imaging Spectroradiometer (MODIS) on board Aqua/Terra. Considering the linear correlation coefficient R, the AVHRR results were similar to those of MERIS with even lower root mean square error RMSE. Not surprisingly, MODIS, with its high spectral coverage, gave the highest R and lowest RMSE. Regarding monthly averaged τa, the results were ambiguous. Focusing on small-scale structures, R was reduced for all sensors, whereas the RMSE solely for MERIS substantially increased. Regarding larger areas like Central Europe, the error statistics were similar to the individual match-ups. This was mainly explained with sampling issues. With the successful validation of AVHRR we are now able to concentrate on our large data archive dating back to 1985. This is a unique opportunity for both climate and air pollution studies over land surfaces.

On Accidental Archaeology

Archaeological excavations in the nineteenth century presented images of past and present collapsed together. Examining the accidental excavation of Roman remains in London and the failed excavation of Silbury Hill in Wiltshire, this essay shows how the intrusion of material from one time into another disrupted notions of linear chronology.

Minimally invasive postmortem telebiopsy

For the past 10 years, medical imaging techniques have been increasingly applied to forensic investigations. To obtain histological and toxicological information, tissue and liquid samples are required. In this article, we describe the development of a low-cost, secure, and reliable approach for a telematic add-on for remotely planning biopsies on the Virtobot robotic system. Data sets are encrypted and submitted over the Internet. A plugin for the OsiriX medical image viewer allows for remote planning of needle trajectories that are used for needle placement. The application of teleradiological methods to image-guided biopsy in the forensic setting has the potential to reduce costs and, in conjunction with a mobile computer tomographic scanner, allows for tissue sampling in a mass casualty situation involving nuclear, biological, or chemical agents, in a manner that minimizes the risk to involved staff.

Evaluating the Impact of the Number of Access Points in Mobile Robots Localization Using Artificial Neural Networks

Localization is information of fundamental importance to carry out various tasks in the mobile robotic area. The exact degree of precision required in the localization depends on the nature of the task. The GPS provides global position estimation but is restricted to outdoor environments and has an inherent imprecision of a few meters. In indoor spaces, other sensors like lasers and cameras are commonly used for position estimation, but these require landmarks (or maps) in the environment and a fair amount of computation to process complex algorithms. These sensors also have a limited field of vision. Currently, Wireless Networks (WN) are widely available in indoor environments and can allow efficient global localization that requires relatively low computing resources. However, the inherent instability in the wireless signal prevents it from being used for very accurate position estimation. The growth in the number of Access Points (AP) increases the overlap signals areas and this could be a useful means of improving the precision of the localization. In this paper we evaluate the impact of the number of Access Points in mobile nodes localization using Artificial Neural Networks (ANN). We use three to eight APs as a source signal and show how the ANNs learn and generalize the data. Added to this, we evaluate the robustness of the ANNs and evaluate a heuristic to try to decrease the error in the localization. In order to validate our approach several ANNs topologies have been evaluated in experimental tests that were conducted with a mobile node in an indoor space.

A self-developed and constructed robot for minimally invasive cochlear implantation

Conclusion: A robot built specifically for stereotactic cochlear implantation provides equal or better accuracy levels together with a better integration into a clinical environment, when compared to existing approaches based on industrial robots. Objectives: To evaluate the technical accuracy of a robotic system developed specifically for lateral skull base surgery in an experimental setup reflecting the intended clinical application. The invasiveness of cochlear electrode implantation procedures may be reduced by replacing the traditional mastoidectomy with a small tunnel slightly larger in diameter than the electrode itself. Methods: The end-to-end accuracy of the robot system and associated image-guided procedure was evaluated on 15 temporal bones of whole head cadaver specimens. The main components of the procedure were as follows: reference screw placement, cone beam CT scan, computer-aided planning, pair-point matching of the surgical plan, robotic drilling of the direct access tunnel, and post-operative cone beam CT scan and accuracy assessment. Results: The mean accuracy at the target point (round window) was 0.56 ± 41 mm with an angular misalignment of 0.88 ± 0.41°. The procedural time of the registration process through the completion of the drilling procedure was 25 ± 11 min. The robot was fully operational in a clinical environment.