2,095 research outputs found
M.-C. Cauvin, A. Gourgaud, B. Gratuze, N. Arnaud, G. Poupeau, J.-L. Poidevin et С. Chataigner (éd.). 1998. L'obsidienne au Proche et Moyen-Orient, Du volcan à l'outil.
No full textPernicka Ernst. M.-C. Cauvin, A. Gourgaud, B. Gratuze, N. Arnaud, G. Poupeau, J.-L. Poidevin et С. Chataigner (éd.). 1998. L'obsidienne au Proche et Moyen-Orient, Du volcan à l'outil.. In: Paléorient, 2000, vol. 26, n°1. pp. 160-162
Early metallurgy at Arslantepe during the Late Chalcolithic and the Early Bronze Age IA-IB periods
No full textA. Hauptmann, E. Pernicka, T.Rehren, Ü.Yalçin (eds.)A. Hauptmann, E. Pernicka, T.Rehren, Ü.Yalçin (eds.
Discovery of ancient gold mining on Thasos (Greece)
No full textNear Kinyra, at the eastern coast of Thasos several ancient galleries were found during the 1979 field- season. The galleries extend up to 100 m into the ridge of Klisidi. They contain numerous traces of ancient mining activity. Mineralogical and chemical studies on limonitic ore samples reveal that gold is the only metal in these galleries which was worth mining in antiquity. The galleries very likely belong to the ancient gold mines which Herodotus described in this area and which, so far, had not been re-located.Près de Kinyra, sur la côte orientale de Thasos plusieurs anciennes galeries furent découvertes pendant la campagne de terrain 1979. Les galeries s'étendent jusqu'à 100 m dans la crête ded Klisidi. Elles contiennent de nombreuses traces d'anciennes activités minières. Les études minéralogiques et chimiques sur des échantillons de minerais limonitiques montrent que l'or était le seul métal qui valait la peine d'être exploité dans l'antiquité dans ces galleries. Celles-ci appartiennent très probablement aux anciennes mines d'or qui ont été décrites par Hérodote dans cette région, et qui jusqu'ici n'avaient pas été localisées.Wagner G.A., Pernicka E., Gentner Wolfgang, Vavelidis M. Discovery of ancient gold mining on Thasos (Greece). In: Revue d'Archéométrie, n°1, 1981. Actes du XXe symposium international d'archéométrie Paris 26-29 mars 1980 Volume III. pp. 313-320
Experiences with a proportional inclined chamber at the european hybrid spectrometer
No full textA new detector of ionizing particles, the ProportionalInclinedChamber, is described. The detector provides a resolution better than 100 μm in the measured coordinate, independent in first approximation of drift velocity variations. It has good, about 300 μm two-track resolution and gives a rough measurement of the angle of the track with a resolution of about 1°. Results obtained with PIC in physics experiments at the European HybridSpectrometer are reported
Review of test methods used for the measurement of hermeticity in packages containing small cavities
No full textThis paper presents a critical review of the traditional and newly proposed test methods used for the measurement of hermeticity in packages with very small cavity volumes. Closed-form expressions of the minimum and maximum true leak rates achievable are provided for the helium fine leak test method. These expressions are shown to provide practical guidelines for the accurate testing of hermeticity for ultrasmall packages. A portfolio of hermeticity test methods is also presented outlining the limitations and advantages of each method.</p
Preliminary Thermal Analysis of the DEXSTR CubeSat
No full textCollin M. Gentry, Missouri University of Science and Technology, USAHenry J. Pernicka, Missouri University of Science and Technology, USAThe Doppler Experiment for Search, Tracking, and Rescue (DEXSTR) is a 3U CubeSat being developed by the Missouri University of Science and Technology (Missouri S&T) and NASA's Goddard Space Flight Center. The low Earth orbit mission uses the Doppler shift of a ground-based beacon signal to geolocate the beacon. This technology has applications in the lunar domain, providing positioning support of assets on the surface of the Moon. The performance of the payload is highly dependent on maintaining its chip-scale atomic clock (CSAC) at a consistent temperature, as the CSAC is needed to accurately determine the Doppler shift. This poses a challenge for DEXSTR and other CubeSats due to their high power densities and limited thermal control capabilities. This study presents a preliminary thermal analysis of DEXSTR as the team progresses toward increasing the model fidelity of the payload and CSAC. Mission constraints and payload requirements are used to create hot and cold cases that account for currently undetermined mission elements such as DEXSTR's specific orbit. A thermal model is built in Thermal Desktop, utilizing the symbolic capabilities of the software to easily adjust model parameters as the mission concept is more fully detailed. This model is used to assess the spacecraft's ability to meet critical thermal requirements, namely the rate of temperature change of the payload and the operating temperature limits of DEXSTR's electronics. From this analysis, initial plans for DEXSTR's thermal control system are outlined. Finally, this study looks ahead to the lunar thermal environment and the unique challenges it will pose to the use of Doppler-shift location technology in cislunar space
Investigation of the pigment use in the Tomba dei Rilievi and other tombs in the Etruscan Banditaccia Necropolis. PIGMENTGEBRAUCH IM GRAB DER RELIEFS UND ANDEREN GRÄBERN DER ETRUSKISCHEN BANDITACCIA NEKROPOLE
No full textThe use of pigments in antiquity, by Romans, Greeks and Egyptians, has been subject to a number of scientific studies. That of contemporary cultures, such as the Etruscans, have been described only in a small number of publications. We investigated the pigment use in five tombs of the Banditaccia Necropolis, near Cerveteri in central Italy: Tomba dei Rilievi (4th century BC), Tomba Mengarelli (7th century BC), Tumolo Policromo (4th century BC), Tomba delle Onde Marine (4th-3rd century BC) and an yet untitled recently excavated tomb (4th century BC (preliminary)). All were carved from the soft tuff bedrock.
A special focus was put on the Tomba dei Rilievi (Tomb of the Reliefs. It is for up to 45 bodies with 13 loculus (burial niches) the largest of the investigated tombs and the only one decorated with painted stucco reliefs
The Archaeological Site HLO1 - A Bronze Age Copper Mining and Smelting Site in the Emirate of Sharjah (U.A.E.)
No full textThe site HLO1 in the Wadi al-Hilo, which means “Hilo river valley”, in the Emirate of Sharjah, UAE, has been excavated since 2007 by a Joint Project of the Directorate of Antiquities of the Government of Sharjah and the Institute of Pre- and Protohistory of Tübingen University under the direction of Sabah A. Jasim from the Sharjah side and Margarethe Uerpmann and Hans-Peter Uerpmann from the Tübingen side. The author was in charge of the actual excavations at the site from 2007 to 2012 and, under the supervision of Ernst Pernicka and Gregor Markl, of the evaluation of finds and findings presented in this dissertation.
The site is situated near the upper end of the valley. Its name translates as “sweet valley”, which is due to its fertility and the rich supply of fresh water in its alluvial underground. Geologically, the area is dominated by Gabbro of the Oman–UAE Ophiolite, which contains small occurrences of copper ore. Some of them indicate traces of surface mining, including a locality at the northern periphery of the archaeological site.
Indications for copper smelting at the site begin during the transition from the Neolithic to the Bronze Age. At present, this is the earliest proof for metallurgy in SE Arabia. Indications for continued occupation of the site during the Bronze and Iron Ages exist in the form of typical pottery from these periods. Direct and indirect evidence for metal production was found in the form of smelting furnaces, workshops, and traces of ore processing. An ingot of pure copper with a weight of 4.6 kg—which, according to the lead isotopes, was produced from local ore—is direct evidence for on-site metallurgy. Isotope analyses of artefacts from other Bronze Age sites indicate that HLO1 is a potential source of copper for a larger area of SE Arabia.
The economic importance of the site and its products is indicated by traces of fortifications. The most obvious is the base of a watchtower of the Umm an-Nar period excavated near the southern access to the site. Traces of a fortification wall were found along the northern border of the site. The stone foundations of a house with several rooms are the only indication for potential domestic buildings. This house was later transformed into a workshop. Presumably, wooden huts, which have left no traces, served as housing for the prehistoric population. An additional outcome of the excavations at HLO1 is the evidence for a Neolithic occupation of the site. Unfortunately, the only evidence for that period are five radiocarbon dates for fireplaces which span the time from the 9th to the 4th millennium BC. Based on stratigraphy, a partly excavated stone structure also belongs to this period. Some few flint artefacts from the corresponding levels are insufficiently characteristic for a typological characterization.
Obvious ruins indicate human presence during the historic period in the form of fairly well preserved rural buildings in the north of the site. They seem to form a “socio-economic unit”, which as such seemed deserving of detailed description before their state of preservation deteriorates further.
A large number of presumably Islamic graves were spared from excavation. A well preserved Islamic watchtower at the southern entrance of HLO1 and the ruins of a noble house on the other side of the wadi indicate that the ecological advantages of the area attracted people at all times.Die Fundstelle HLO1 im Wadi Hilo (Emirat Sharjah, VAE) wird seit 2007
von einem gemeinsamen Projekt des Instituts für Naturwissenschaftliche
Archäologie der Universität Tübingen unter Leitung von Margarethe und
Hans-Peter Uerpmann und des Antikendirektorats des Emirats Sharjah (VAE) unter
Leitung von Sabah A. Jasim untersucht. Der Autor dieser Dissertation hat die
Grabungen an der Fundstelle HLO1 von 2007 bis 2012 geleitet. Die Auswertung von
Funden und Befunden unter Anleitung durch Ernst Pernicka und Gregor Markl sind
Gegenstand der vorliegenden Dissertation.
Die Fundstelle liegt am oberen Ende des Wadi Hilo auf einer alten Wadi Terrasse
am Ostrand des Tales. Sein Name bedeutet "`Süßes Tal"', was sich auf seine
Fruchtbarkeit und den Reichtum an Wasser in seinem alluvialen Untergrund
bezieht. Geologisch wird die Gegend durch Gabbro-Formationen des
Oman-VAE-Ophioliths bestimmt, der kleine Vorkommen von Kupfererz enthält.
Einige davon zeigen Hinweise auf einen obertägigen Abbau, darunter auch ein
kleines Vorkommen nahe der Fundstelle.
Hinweise auf Kupferverhüttung am Fundplatz beginnen am Übergang vom Neolithikum
zur Bronzezeit. Derzeit sind dies die ältesten Spuren metallurgischer
Aktivitäten in Südost-Arabien. Eine Besiedlung des Fundplatzes von der Bronze-
bis zur Eisenzeit wird durch charakteristische Keramik-Funde dieser Perioden
belegt. Direkte und indirekte Belege für die Erzverhüttung liegen in Form von
Schmelzöfen, Werkstätten, Schlacken und Spuren der Erz-Aufbereitung vor. Der
Fund eines Barrens aus reinem Kupfer mit einem Gewicht von 4,6kg – der nach
Ausweis der Blei-Isotopie aus lokalem Erz gewonnen wurde – ist ein klarer
Beleg für Kupfergewinnung vor Ort. Isotopenanalysen an Bronzefunden anderer
Fundstellen weisen darauf hin, dass HLO1 eine potentielle Produktionsstätte von
Kupfer für größere Gebiete in SO-Arabien gewesen ist.
Die ökonomische Bedeutung der Fundstelle und ihrer Produkte ergibt sich aus den
Spuren einer aufwendigen Befestigungsanlage. Ihr auffälligster Bestandteil ist
der Stumpf eines Turmes, der in die Umm an-Nar Phase der Frühen Bronzezeit
datiert. Er liegt auf der Südseite der Fundstelle und kontrolliert den dortigen
Zugang. Weniger gut erhaltene Spuren einer Befestigungsanlage wurden entlang
der Nordseite gefunden. Grundmauern eines Hauses mit mehreren Räumen sind die
einzigen Spuren potenzieller Wohnbauten. Dieses Haus wurde später zu einer
metallurgischen Werkstätte umgebaut. Vermutlich hat die prähistorische
Bevölkerung in Holzbauten gelebt, die keine archäologischen Spuren hinterlassen
haben.
Ein zusätzliches Ergebnis der Ausgrabungen sind die klaren Hinweise auf eine
Nutzung der Fundstelle im Neolithikum. Leider besteht der Nachweis für die
Periode nur aus fünf Radiocarbon-Daten, die den Zeitraum vom 9. bis ins 4.
Jahrtausend v. Chr. belegen. Auf Grund der Stratigraphie gehört auch eine
partiell ergrabene Steinstruktur zu dieser Periode. Einige Silexartefakte aus
den zugehörigen Schichten sind zu uncharakteristisch um eine typologische
Zuordnung zu ermöglichen.
Augenfällige Ruinen belegen die menschliche Anwesenheit in historischer Zeit.
Diese liegen am Nordrand der Fundstelle. Da sie die sozio-ökonomische Struktur
der Ansiedlung widerspiegeln, rechtfertigten sie eine detaillierte Beschreibung
und Dokumentation bevor sie weiter zerfallen
Single event upset studies on the CMS tracker APV25 readout chip
No full textThe microstrip tracker for the CMS experiment at the CERN Large Hadron Collider will be read out using APV25 chips. During high luminosity running the tracker will be exposed to particle fluxes up to 10**7 cm**-**2 s**-**1, which raises concerns that the APV25 could occasionally suffer Single Event Upsets (SEUs). The effect of SEU on the APV25 has been studied to investigate implications for CMS detector operation and from the viewpoint of detailed circuit operation, to improve the understanding of its origin and what factors affect its magnitude. Simulations were performed to reconstruct the effects created by highly ionising particles striking sensitive parts of the circuits, along with consideration of the underlying mechanisms of charge deposition, collection and the consequences. A model to predict the behaviour of the memory circuits in the APV25 has been developed and data collected from dedicated experiments using both heavy ions and hadrons have been shown to support it
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