bluuebunny/crossref_metadata_2025 huggingface dataset:
A Visual Feedback Approach for Focal Plane Stabilization of a High Resolution Space Camera (Ein Ansatz zur Bildgestützten Regelung für die Fokalebenenstabilisierung einer Hochauflösenden Satellitenkamera)
Authors: Janschek Klaus , Tchernykh Valerij , Dyblenko Serguei , Flandin Grégory
Published: October 2005

In this article a new concept of a smart satellite pushbroom imaging system with internal compensation of attitude instability effects is presented. The compensation is performed within the optical path by an active opto-mechatronic stabilization of the focal plane image motion in a closed loop system with visual feedback. The real-time image motion measurement is derived from an auxiliary matrix image sensor and an onboard optical correlator. In this way the effects of attitude instability, vibrations and micro shocks can be neutralized, the image quality is improved and the requirements to the satellite attitude stability can be reduced considerably. The paper describes the principles of operation, the main system elements and gives detailed performance figures derived from a simulation performance model, which contains all relevant components of the smart imaging system.
Bildoptimierung durch kontrolliertes Aktives Sehen und Bildfusion (Image Optimization via Controlled Active Vision and Image Fusion)
Authors: Beyerer Jürgen , Puente León Fernando
Published: October 2005

Mit nur einem Kamerabild alleine lässt sich bei schwierigen Objekten oftmals keine Darstellung visuell ausreichender Güte erzielen, unter Umständen auch dann nicht, wenn man die Aufnahmekonstellation optimal wählen würde. Der Grund liegt in der vielgestaltigen Wechselwirkung zwischen Beleuchtung, Objekt und Aufnahmeoptik einerseits und der eingeschränkten „Wahrnehmungsfähigkeit“ eines gängigen intensitätsempfindlichen 2D-Sensors einer Standardkamera für das informationstragende Lichtfeld der Szene andererseits. Für Bilder höherer Güte werden in diesem Aufsatz Bildserien unter gezielter Variation der Parameter der Aufnahmekonstellation gewonnen. Solche Serien, die wesentlich mehr Information tragen als ein einzelnes Bild, werden zu Resultatbildern mit einer von Einzelbildern nicht erreichbaren Qualität verschmolzen.

Am Beispiel der Gewinnung eines Bildes mit gleichmäßigem Signal-zu-Rausch-Verhältnis auf hohem Niveau wird ein finaler Fusionsansatz demonstriert. Ein solcher Ansatz ist sinnvoll, wenn anhand der Bildserie bereits sehr gut auf die Qualität des zukünftigen Fusionsresultates geschlossen werden kann.

Ein zweites Beispiel zeigt, wie für ein optisch schwieriges biologisches Präparat eine Bildserie durch zweidimensionale Variation der Beleuchtungsrichtung gewonnen und iterativ zu einem hochwertigen Ergebnisbild fusioniert wird. Die Qualität des Resultates der mitlaufenden Fusion bestimmt hier den Abbruch der Serienakquisition. In beiden Beispielen wird Bildinformation in die Bildseriengewinnung rückgekoppelt, und so der Akquisitionsprozess im Hinblick auf einen umfassenden aufgabenspezifischen Informationsgewinn geregelt.
Industrial Use of H∞ Optimisation for High Performance Laser Communication Pointing System: the SILEX Application (Industrieller Einsatz von H∞-Optimierung für die hochgenaue Ausrichtung des Laserkommunikationssystems SILEX)
Authors: Frapard Benoît , Griseri Gilbert , Guyot Phillippe
Published: October 2005

SILEX consists of an optical link between one optical terminal on board the observation satellite SPOT 4 in low earth orbit, and another optical terminal on board the telecommunication satellite ARTEMIS, in geostationary orbit. The first image transmission via SILEX has been performed on November 30th, 2001. The Pointing Acquisition and Tracking subsystem has raised the challenge and given the opportunity to obtain sub micro radian pointing performances from the tracking loop tuning. H∞ optimisation has demonstrated to be the adequate approach to comply with all the pointing constraints. Result of several years of theoretical work, this application was the first of many other industrial applications in EADS Astrium. This paper describes in the details the selected approach for SILEX tracking loop tuning.
Einsatz optischer Technologien zur Regelung des Laserstrahlschweißprozesses (Application of Optical Technologies for Closed Loop Control of Laser Beam Welding)
Authors: Bollig Alexander , Mann Stefan , Beck Ralf , Kaierle Stefan
Published: October 2005

Das Schweißen mit Laserstrahlung ist ein innovatives optisches Fügeverfahren, das sich gegenüber konventionellen Schweißtechniken durch höhere erzielbare Schweißgeschwindigkeiten und geringere Nahtbreiten bei gleichzeitig gesteigerter Nahttiefe auszeichnet. Wesentliche Qualitätskriterien sind neben erkannten Fehlern der Schweißnaht die Einschweißtiefe und die Nahtbreite, die die Nahtgeometrie bilden. In diesem Beitrag werden optische Sensoren für die Erfassung relevanter Prozessgrößen beschrieben sowie hierauf aufbauend ein prädiktives Regelungskonzept, in dem die Stellgrößen Laserleistung und Fokuslage unter Berücksichtiung der zukünftigen Bahngeschwindigkeit optimiert werden. Bei der Modellierung des physikalisch komplexen, nichtlinearen Prozesses wird ein Neuronales Netz mit externer Dynamik verwendet. Ergebnisse aus der Anwendung des Regelungskonzepts auf den realen Schweißprozess werden vorgestellt.
Max-Plus-Algebra, Teil 1 (Max-Plus Algebra, Part 1)
Authors: Rambow Thomas , Kiencke Uwe
Published: October 2005

Dieser Beitrag befasst sich mit der Max-Plus-Algebra als mathematisches Werkzeug zur Beschreibung und Analyse ereignisdiskreter Systeme. Es werden die theoretischen Grundlagen zur graphischen oder mathematischen Beschreibung der kausalen Zusammenhänge und der logischen Abfolge von Ereignissen innerhalb des Systems zur Verfügung gestellt. Ereignisdiskrete Systeme, die sich durch Digraphen beschreiben lassen, können mit der Max-Plus-Algebra analytisch behandelt werden. Die Struktur des Systems wie z.B. die Koordination und die Synchronisation einzelner Komponenten, kann mit Hilfe der Max-Plus-Algebra modelliert werden. Anhand der gewonnenen Gleichungen ist es möglich, das Systemverhalten zu beschreiben und zu analysieren, z.B. durch die Berechnung von Eigenwerten und Eigenvektoren.
Effective Methods for Reinforcement Learning in Large Multi-Agent Domains (Leistungsfähige Verfahren für das Reinforcement Lernen in komplexen Multi-Agenten-Umgebungen)
Authors: Riedmiller Martin , Withopf Daniel
Published: October 2005

Robotic soccer requires the ability of individually acting agents to cooperate. The simulation league of RoboCup therefore offers an ideal testbed for evaluating multi-agent methods. In this paper we discuss how Reinforcement Learning (RL) methods can be succesfully applied within the scenario of learning to cooperatively score a goal. Due to the complexity of the task, enhanced methods of learning have to be applied. We discuss several approaches from literature and also present an own approach. All approaches are evaluated on a discretized version of robotic soccer, which we call gridworld soccer.
Reinforcing the Driving Quality of Soccer Playing Robots by Anticipation (Verbesserung der Fahreigenschaften von fußballspielenden Robotern durch Antizipation)
Authors: Gloye Alexander , Wiesel Fabian , Tenchio Oliver , Simon Mark
Published: October 2005

This paper shows how an omnidirectional robot can learn to correct inaccuracies when driving, or even learn to use corrective motor commands when a motor fails, whether partially or completely. Driving inaccuracies are unavoidable, since not all wheels have the same grip on the surface, or not all motors can provide exactly the same power. When a robot starts driving, the real system response differs from the ideal behavior assumed by the control software. Also, malfunctioning motors are a fact of life that we have to take into account. Our approach is to let the control software learn how the robot reacts to instructions sent from the control computer. We use a neural network, or a linear model for learning the robot's response to the commands. The model can be used to predict deviations from the desired path, and take corrective action in advance, thus increasing the driving accuracy of the robot. The model can also be used to monitor the robot and assess if it is performing according to its learned response function. If it is not, the new response function of the malfunctioning robot can be learned and updated. We show, that even if a robot loses power from a motor, the system can re-learn to drive the robot in a straight path, even if the robot is a black-box and we are not aware of how the commands are applied internally.
Robot Localization through Region Tracking (Ortung eines Roboters durch Verfolgen homogener Farbregionen)
Authors: Hundelshausen Felix von
Published: October 2005

In this article we describe a self-localization method for soccer robots that solves the “Where am I”-problem by visually perceiving and understanding the structure of the field lines on a soccer playing field. The method accrued from our participation in the RoboCup Middle Size league where fully autonomous robots play soccer on a 8 × 12 m field. The method was successfully applied by our FU-Fighter's Middle Size robots during the world championships in 2004, where we placed 4th.
From Perception to Action in the Sony Four-Legged Robot League (Von der Wahrnehmung zur Aktion in der Sony Four-Legged Robot League)
Authors: Röfer Thomas
Published: October 2005

This article describes the architecture and the methods developed by the GermanTeam, the RoboCup world champion 2004 in the Sony Four-Legged Robot League. The architecture supports developing software in a joint effort of many researchers both in sub-teams of the GermanTeam itself, but also in several other teams in the league. In addition to the architecture, the different components required to play soccer in the four-legged league are presented: perception, world modeling, behavior control, and motion control.
The VolksBot Concept – Rapid Prototyping for real-life Applications in Mobile Robotics (Das VolksBot Konzept – Ein Baukastensystem für anwendungsnahes Rapid-Prototyping mobiler Roboter)
Authors: Wisspeintner Thomas , Bose Abheek
Published: October 2005

VolksBot is a modular mobile robot construction kit, developed during the last 3 years to fit the needs in research and education as well as in application-based rapid prototyping. The component-based approach offers a plug-in architecture with open interfaces in electronic hardware, software and mechanics. The lean and open structure fosters reusability of existing modules, both in hardware and software. Initially this concept was successfully applied to indoor applications. The article addresses this concept and shows how it was extended to fit the higher demands of real-life scenarios like outdoor or rough terrain. As a result, the VolksBot RT (Rough Terrain) construction kit is presented. Examples are given, how domain-specific rapid prototyping of variants of such platforms could be achieved in the fields of Urban Search and Rescue and Autonomous Transportation.
Simultanous Mapping and Localization of Rescue Environments (Gleichzeitiges Kartieren und Lokalisieren von Rescue-Umgebungen)
Authors: Surmann Hartmut , Pervölz Kai , Nüchter Andreas , Lingemann Kai , Hertzberg Joachim , Hennig Matthias
Published: October 2005

Deploying rescue workers in an urban setting is often a perilous, time-, power-, and force-consuming job, and robot systems to assist in this effort are needed. A fundamental task for rescuer is to localize and salvage injured persons. To this end, robotic systems are used for mapping a site and for remote inspection of suspicious objects. The mobile robot Kurt3D is the first rescue robot that is capable of mapping its environment in 3D and self localize in all six degrees of freedom, i. e., considering its x, y and z positions and the roll, yaw and pitch angles. This capability allowed the small robot to win the Vice World Championship at the RoboCup Rescue competition 2004 at Lisbon.
Humanoid Soccer Robots (Humanoide Fußballroboter)
Authors: Behnke Sven
Published: October 2005

Humanoid robots are enjoying increasing popularity as a research tool. As step towards the long-term goal of winning against the FIFA world champion, the RoboCup Federation added in 2002 a league for humanoid robots to its annual soccer competitions. In this paper, the Humanoid League competitions that took place so far are reviewed. The different approaches for the design of robot hardware and the software for perception and behavior control of soccer playing humanoid robots are discussed. The paper concludes with an outlook to the future of the RoboCup Humanoid League.
Data Mining: The Next Generation (Data Mining: Die nächste Generation)
Authors: Freytag Johann-Christoph , Ramakrishnan Raghu , Agrawal Rakesh
Published: October 2005

Data Mining has enjoyed great popularity in recent years, with advances in both research and commercialization. The first generation of data mining research and development has yielded several commercially available systems, both stand-alone and integrated with database systems, produced scalable versions of algorithms for many classical data mining problems and introduced novel pattern discovery problems. In July 2004 researchers from a variety of backgrounds assembled at the Dagstuhl Conference Center in Germany for a workshop to re-assess the current directions of the field, to identify critical problems that require attention, and to discuss ways to increase the flow of ideas across the different disciplines that Data Mining has brought together. The workshop did not seek to draw up an agenda for the field of data mining. Rather, it offers the participants' perspective on two technical directions – compositionality and privacy – and describes some important application challenges which drove the discussion.
Ein Differential-Interferometer mit konfokalem Positionssensor zum Messen kleinster Verschiebungen eines stark gekrümmten Prüflings (A Differential Interferometer with Confocal Position Sensor for the Measurement of Very Small Displacements of an Object with Narrow Curvature)
Authors: Li Zhi , Herrmann Konrad , Pohlenz Frank , Popadic Radovan
Published: October 2005

Dieser Beitrag behandelt die Entwicklung eines Differential-Interferometers mit einer neuen Konfiguration, um die Verschiebung von stark gekrümmten Prüflingen zu messen. In den vorhandenen Aufbau eines Differential-Interferometers wurde ein konfokaler Sensor mit dem Ziel integriert, die relative Position zwischen dem Prüfling und dem Strahlteiler zu bestimmen. Eine Experimentaleinrichtung wurde aufgebaut, um ein Tiefenmesssystem in einem kommerziellen Nanoindentation-Gerät zu kalibrieren, die auch die Vorteile des entwickelten Differential-Interferometers deutlich demonstriert.
Interferometrischer Sensor und interferometrisches Kalibriersystem für Ultrapräzisions-Anwendungen (Interferometric Sensor and Calibration System for High-Precision Applications)
Authors: Welter Matthias , Manske Eberhard , Jäger Gerd
Published: October 2005

Es wurde ein kompaktes, ultrapräzises Laserkalibriersystem aufgebaut und erfolgreich getestet. Das System besteht unter anderem aus einem neuen interferometrischen Winkel- und Längensensor und einer DSP-gestützten Signalverarbeitungseinheit. Es wird mittels Matlab gesteuert, sodass Messabläufe und Datenauswertung sehr einfach und flexibel gestaltet werden können. Mit Hilfe eines Autokollimators, eines induktiven Tasters und eines AFM konnten die Eigenschaften des Kalibriersystems erfolgreich demonstriert werden. Derzeit sind statische eindimensionale Kalibrierungen mit Schrittweiten von 20 pm bis ±6 μm sowie dynamische bei Frequenzen bis 2 kHz möglich.
Nutzung der Ultraschallgeschwindigkeitsmessung für die Ermittlung des Fettgehaltes in Milch (Use of the Ultrasound Velocity Measurement for the Determination of the Fat Content in Milk)
Authors: Liebsch Wolfgang , Frense Dieter , Nacke Thomas , Beckmann Dieter
Published: October 2005

Dieser Beitrag befasst sich mit der selektiven Bestimmung einer einzelnen Komponente in einer Suspension am Beispiel von Milch. Ziel ist es, den Fettgehalt von Rohmilch zu bestimmen. Die Messung erfolgt über die Auswertung einer integrativen Messgröße, der Ultraschallgeschwindigkeit, in einem Temperaturprofil. Zur Datenreduktion werden die Messwerte approximiert. Die Koeffizienten der Approximation ermöglichen eine effiziente Auswertung mittels eines neuronalen Netzes. Im Anschluss erfolgt ein Vergleich der Ergebnisse mit Referenzmessungen und eine Diskussion der Messfehler dieser Methode.
Between anti‐Semitism and Islamophobia: Some thoughts on the new Europe
Authors: Bunzl Matti
Published: October 2005

The apparent resurgence of hostility against Jews has been a prominent theme in recent discussions of Europe. At the same time, the adversities of the Muslim populations on the continent have received increasing attention as well. In this article, I attempt a historical and cultural clarification of the key terms in this debate. I argue against the common impulse to analogize anti‐Semitism and Islamophobia. Instead, I offer an analytic framework that locates the two phenomena in different projects of exclusion. Anti‐Semitism was invented in the late 19th century to police the ethnically pure nation‐state; Islamophobia, by contrast, is a formation of the present, marshaled to safeguard a supranational Europe. Whereas traditional anti‐Semitism has run its historical course with the supersession of the nation‐state, Islamophobia threatens to become the defining condition of the new Europe.
Edward Said and the political present
Authors: Abu El‐Haj Nadia
Published: October 2005

This article offers a reading of Edward Said's legacy. It engages Said's scholarly and political insights, on the one hand, and his vision of and life as an intellectual, on the other hand. The article focuses on his broader conceptual and methodological interventions, his analysis of the politics of empire (in the Middle East), and his passionate attachment to the question of Palestine. It also contextualizes Said's work in light of the contemporary political moment, arguing that he and that for which he is seen to stand have emerged as key flash points in the latest U.S. culture wars.
Between heritage and countermemory: Varieties of historical representation in a West German community
Authors: Eidson John R.
Published: October 2005

Contrasting views of the past are often understood in terms of dichotomies (e.g., hegemonic–counterhegemonic and regressive–progressive), but ethnographic data gathered in a German community suggest the need for a more differentiated approach. The public presentation of history in that community corresponds to one of three conventions: (1) the commemoration of the founding of local institutions by their members, (2) “hometown history,” an avocation of the local bourgeoisie, and (3) citizens' initiatives for coming to terms with the Nazi past. German‐area specialists have tended to dismiss the first two types and to valorize the third, but different representations of the past in the present are best viewed as varieties of symbolic capital, which members of different social groups employ in the institutional settings to which they have access and in which they are authorized to play active roles.
An “impossible” transmission: Youth religious memories in Guinea–Conakry
Authors: Berliner David
Published: October 2005

Memory, persistence, and cultural transmission are hot topics in anthropology today. Contributing to an increasing anthropological interest in youth agency, in this article I invite readers to look at youth as a crucial site for understanding issues of religious memory and cultural transmission. In the past five decades, Bulongic people (Guinea–Conakry) have undergone significant religious changes caused by the introduction of Islam, which has led to the official disappearance of pre‐Islamic rituals. In this article, I explore how young Bulongic remember a pre‐Islamic past that they have never experienced. I argue that, to understand how they assimilate and perpetuate this religious heritage, one must examine the subtle processes of intergenerational transmission through which their memories are dynamically shaped.
Encounters with the “peasant”: Memory work, masculinity, and low fertility in Italy
Authors: Krause Elizabeth L.
Published: October 2005

The peasant in Italy has all but vanished as an exemplar of an economic way of life but as a social figure has relevance to trends such as the transformation to small families. Ethnographic “encounters” provide the basis for my explorations into the trauma and meaning of the historical experiences that find expression in Italian women's low fertility rates. Current family‐making practices have resulted from historical adjustments deeply linked to economic shifts that involved the unraveling of a patriarchal hierarchy and necessitated a subsequent reworking of gendered subjects situated in new socioeconomic conditions. An ethnographic focus on memory work reveals that the social figure of the peasant persists in meaningful ways that shape people's family‐making practices.
Family firms amidst the creative destruction of capitalism
Authors: Marcus George E.
Published: October 2005

In terms of anthropology's past interests, the study of family firms seems a “natural” way into the ethnography of contemporary capitalism. True, but as Sylvia Yanagisako's rich and sensitive study demonstrates, this is so by productively frustrating central ideas in anthropology like “culture” and “kinship” without resolution in alternative concepts.
Image and instrumentality in a Xavante politics of existential recognition: The public outreach work of EtÉnhiritipa Pimentel Barbosa
Authors: Graham Laura R.
Published: October 2005

This analysis of one Xavante group's innovative projects to represent Xavante culture to nonindigenous audiences reveals multiple and complex perceptions of instrumentalities as well as political goals. Unlike many contemporary Native (Amazonian and other) groups that use aspects of their culture to attract support and achieve concrete political goals, local objectives are relatively abstract and future oriented, having to do with public “image” and “existential recognition.” Analysis illustrates that local ideas about indigenous cultural displays aimed primarily at nonindigenous audiences, including “identity politics” and apparently straightforward cultural commodification, may not neatly correspond with anthropologists' or other outsiders' expectations. Overly narrow interpretive foci may cause anthropologists to overlook the potential for multiple and complex objectives and a diversity of locally significant dimensions.
Global movements and local historical events: Itelmens of Kamchatka appeal to the United Nations
Authors: Koester David
Published: October 2005

In this article, I examine the institutional, cultural, and discursive foundations of a historical event. I explicate global, transnational, national, intercultural, ethnic, regional, local, and personal realms of understanding as well as a range of discursive and pragmatic strategies as they came into play in a schoolroom meeting that led to the writing of a letter to the United Nations for help. The case presented is that of a group of people in a small, majority‐indigenous village in Kamchatka in the Russian Far East, who, in 1993, after the collapse of the Soviet government and its support network, decided to turn to the United Nations for help.
Eritrea on‐line: Diaspora, cyberspace, and the public sphere
Authors: Bernal Victoria
Published: October 2005

For Eritreans in diaspora, identities are deterritorialized, one's most pressing communication may be with far‐flung strangers in cyberspace, and one's political engagement is centered on a distant homeland. Eritrean experiences, thus, seem to bring together various qualities that scholars have been grappling with in trying to chart the implications of the infotech revolution and life on‐line, in seeking to understand processes of transnationalism and globalization, and in charting the elusive construction of community in the postmodern age. Through an analysis of the social history of www.dehai.org, a website developed by Eritreans in diaspora, I explore the ways that new forms of technological and geographical mobility are changing the conditions not just of capitalist production but also of knowledge production and the constitution of publics, public spheres, communities, and nations.
Culture, state, and security in Europe: The case of citizenship and integration policy in Estonia
Authors: Feldman Gregory
Published: October 2005

In this article, I examine how a territorial imaginary conflating culture, territory, nation, and security allows “elites of statecraft” in Europe to frame citizenship and integration policy as (inter)national security matters. Focusing on post‐Soviet Estonia, I argue that this imaginary legitimized the denial of citizenship to Soviet‐era Russian speakers and enabled the government's integration policy objective of creating the “Estonian cultural domain.” Drawing on historical, archival, and ethnographic research, I demonstrate how the invocation of national security justified these events and how the territorial imaginary structured the making of integration policy from the 1991 reestablishment of independence to E.U. accession in 2004.
BeforeTurannoiWere Tyrants: Rethinking a Chapter of Early Greek History
Authors: Anderson Greg
Published: October 2005

Abstract According to classical and postclassical sources, the early Greekturannoi were, by definition, illegitimate rulers who overturned existing political arrangements and installed rogue monarchic regimes in their place. And on this one fundamental point at least, modern observers of archaicturannides seem to have little quarrel with their ancient informants. To this day, it remains axiomatic that Cypselus, Peisistratus, and the rest were autocrats who gained power by usurpation. Whatever their individual accomplishments, they were still, in a word, "tyrants." Relying mostly on evidence from the contemporary literary and material records, my paper aims to challenge this time-honored conventional wisdom and restore the firstturannoi to the political mainstream.
Iphigeneia in Philadelphia
Authors: Burrell Barbara
Published: October 2005

Abstract A long-misinterpreted Roman provincial coin shows a mythological scene in order to make a remarkable claim: that Iphigeneia, Orestes, and Pylades fled from the land of the Taurians to Philadelphia in Lydia (modern Alaşehir in Turkey), and there set up their stolen image, identified by the Philadelphians as their patron Artemis Anaitis. This Persianized goddess was generally depicted as an Anatolian image almost identical to the Artemis of Ephesos; it is the bond between the two goddesses that may be the immediate basis of this coin's alliance with Ephesos, but the long-term intent may have been to form a voting bloc within the provincial association of cities. Philadelphia, though a relatively recent foundation, often allied itself with the oldest and greatest of Asia's cities and petitioned Roman emperors in order to raise its rank to rival that of its eminent neighbor Sardis. With this coin Philadelphia sought not only to gain allies, but, by grounding its history in the depth of mythological time, to advance itself among its rivals in Roman Asia.
Parry in Paris: Structuralism, Historical Linguistics, and the Oral Theory
Authors: Vet Thérèse de
Published: October 2005

Abstract This paper investigates the origins of the Oral Theory as formulated by Milman Parry in Paris during the late 1920s by reexamining the scholarship on which it rests. Parry's Oral Theory compared the texts of oral performances in Yugoslavia with the Homeric texts in order to shed light on the presumed oral origins of the latter. His work integrated the work of the linguist and Indo-Europeanist Antoine Meillet, the linguist and scholar of oral poetics Matthias Murko, and the anthropologists Lucien Lévy-Bruhl and Marcel Jousse.
Mimesis or Phantasia? Two Representational\\ Modes in Roman Commemorative Art
Authors: Koortbojian Michael
Published: October 2005

Abstract The commemorative forms of the Romans are marked by the ubiquity of two contrasting presentational modes: one essentially mimetic, rooted in the representational power of artistic forms, the other abstract and figurative, dependent on the presentation of cues for the summoning of absent yet necessary images. The mimetic mode was thoroughly conventional, and thus posed few problems of interpretation; the figurative knew no such orthodoxy and required a different and distinctive form of attention. At the tomb, epigraphic and sculptural forms, each in its characteristic manner, addressed an audience habituated by tradition to respond to both of these modes, to grasp their differences, and to rise to the challenge implicit in the very fact of their contrast.
Traces of a Freed Language: Horace, Petronius, and the Rhetoric of Fable
Authors: Marchesi Ilaria
Published: October 2005

Abstract This paper investigates the status that the genre of fable acquires when it is employed in literature. In particular, it surveys Horace's treatment of fables in the Satires andEpistles and the carefully controlled circumstances in which zoomorphic language is allowed to emerge during the banquet at Trimalchio's in Petronius' Satyrica. The analysis of the distribution of fables in Horace shows that for the Roman literary public the act of speaking through fables bore in itself a negative connotation, so much that the moral discourse of the satirist needed at first to provide additional justification in order to incorporate them: from vindication of ingenuitas and shifts in narrative voice, to use of rhetorical misnomers and eventually of philosophical frankness. Petronius' text, in turn, suggests that what is wrong with fable is precisely its being reminiscent of a servile past. During the dinner at Trimalchio's allusions to recognizable fable plots and zoomorphic language are allowed to surface only during a momentary absence of the host. This circumstance suggests that fable is not just another literary genre among the many genres abused in Trimalchio's house: for both the host and his freedmen guests fables are an uncomfortable reminder of an enduring past inscribed in their language.
Agriculture, Writing, and Cato's Aristocratic Self-Fashioning
Authors: Reay Brendon
Published: October 2005

Abstract This article investigates the interplay of agriculture and writing in the elder Cato's aristocratic self-fashioning (both his individual self-representation, that is, and his construction of aristocracy more broadly). I argue that the De Agricultura represents Cato and his contemporaries as individual, small-plot farmers by making explicit the agricultural inflection of a more general masterly extensibility, i.e., that slaves were prosthetic tools with which owners accomplished various tasks, a move that in turn reveals the ubiquitous, assiduous “labor” of the individual owner. The preface's valorization of small-plot farmers, past and present, contextualizes the owner's “labor” both culturally and historically (the one by means of the other), and thereby seeks to bridge the agricultural and temporal divide that separates Cato and his contemporaries from their esteemed predecessors.
FUNDAMENTALISSUES IN THEEVOLUTIONARYPSYCHOLOGY OFMUSIC: Assessing Innateness and Domain Specificity
Authors: JUSTUS TIMOTHY , HUTSLER JEFFREY J.
Published: October 2005

EVOLUTIONARY PSYCHOLOGY OFTEN does not sufficiently document the innate constr aint and domain specificity required for strong adaptationist argument. We develop these criteria within the domain of music. First, we advocate combining computational, developmental, cross-cultural, and neuroscience research to address the ways in which a domain is innately constrained. Candidate constraints in music include the importance of the octave and other simple pitch ratios, the categorization of the octave into tones, the importance of melodic contour, tonal hierarchies, and principles of grouping and meter. Second, we advocate combining psychological, neuroscience, and genetic research across cognitive domains to address the domain specificity of such constraints. Currently available evidence suggests that the innate constraints in music are not specific to that domain, making it unclear which domain(s) provided the relevant selection pressures.
THE ORIGINS OF MUSIC: INNATENESS, UNIQUENESS, AND EVOLUTION
Authors: McDERMOTT JOSH , HAUSER MARC
Published: October 2005

THE ORIGINS and adaptive significance of music, long an elusive target, are now active topics of empirical study, with many interesting developments over the past few years. This article reviews research in anthropology, ethnomusicology, developmental and comparative psychology, neuropsychology, and neurophysiology that bears on questions concerning the origins and evolution of music. We focus on the hypothesis that music perception is constrained by innate, possibly human- and musicspecific principles of organization, as these are candidates for evolutionary explanations. We begin by discussing the distinct roles of different fields of inquiry in constraining claims about innateness and adaptation, and then proceed to review the available evidence. Although research on many of these topics is still in its infancy, at present there is converging evidence that a few basic features of music (relative pitch, the importance of the octave, intervals with simple ratios, tonality, and perhaps elementary musical preferences) are determined in part by innate constraints. At present, it is unclear how many of these constraints are uniquely human and specific to music. Many, however, are unlikely to be adaptations for music, but rather are probably side effects of more general-purpose mechanisms. We conclude by reiterating the significance of identifying processes that are innate, unique to humans, and specific to music, and highlight several possible directions for future research.
PRODUCTION AND SYNCHRONIZATION OF UNEVEN RHYTHMS AT FAST TEMPI
Authors: REPP BRUNO H. , LONDON JUSTIN , KELLER PETER E.
Published: October 2005

THIS STUDY EXAMINED PRODUCTION and synchronization of eight uneven rhythms (set A: 2+3, 3+2; set B: 2+2+3, 2+3+2, 3+2+2; set C: 2+3+3, 3+2+3, 3+3+2) at rates that made it difficult to subdivide the component intervals into elementary metrical pulses. The main questions were how interval ratios would change as a function of tempo within this range, and whether metrical downbeat location (which distinguishes the rhythms within each set) would be reflected in any of the dependent measures. Musically trained participants tapped each rhythm cyclically in synchrony with an auditory template and then continued to tap in three ways: self-paced, paced by a sequence of downbeats, or paced by a rapid stream of isochronous subdivisions. Each task was carried out at eight tempi. The third task assessed the temporal limit of subdivision for these rhythms (about 6 Hz), which was exceeded by most tempi. Results showed that the mean long–short (3:2) interval ratio was already larger than 1.5 at the slowest tempo in rhythm sets A and B, and increased with tempo in sets B and C, but did not approach 2. Uneven rhythms thus can be produced without mental subdivision, but only with substantial enhancement of the contrast between long and short intervals. Metrical downbeat location had no reliable effect on interval ratios but was reflected in more forceful downbeat taps and in different alignments of taps with a pacing sequence. In general, effects of temporal grouping (between rhythm sets) outweighed those of metrical interpretation (within rhythm sets).
IS THERE A PERCEPTION-BASED ALTERNATIVE TO KINEMATIC MODELS OF
TEMPO RUBATO?
Authors: HONING HENKJAN
Published: October 2005

THE RELATION BETWEEN MUSIC and motion has been a topic of much theoretical and empirical research. An important contribution is made by a family of computational theories, so-called kinematic models, that propose an explicit relation between the laws of physical motion in the real world and expressive timing in music performance. However, kinematic models predict that expressive timing is independent of (a) the number of events, (b) the rhythmic structure, and (c) the overall tempo of the performance. These factors have no effect on the predicted shape of a ritardando. Computer simulations of a number of rhythm perception models show, however, a large effect of these structural and temporal factors. They are therefore proposed as a perception-based alternative to the kinematic approach.
Transmission electron microscopy observation of the microemulsion process and the magnetic properties of the resultant nanocrystalline Ni–Zn ferrites
Authors: Yan Shifeng , Zhou Enle
Published: October 2005

Nanocrystalline Ni–Zn ferrite particles (Ni0.5Zn0.5Fe2O4) have been successfully produced by microemulsion method. The microemulsion process was first observed by transmission electron microscopy examination. The particles exhibit a blocking temperature of 95 K. They do not attain saturation magnetization even at a high field of 50 KOe. The saturation magnetization at 300 K is 29.8 emu/g, which is significantly lower than that reported for the bulk ceramic standard. Below the blocking temperature, the Ni0.5Zn0.5Fe2O4 nanocrystalline particles exhibit a hysteretic feature. The remanent magnetization and coercivity at 2K are 10.45 emu/g and 453 Oe, respectively.
Vickers hardness and compressive properties of bulk metallic glasses and nanostructure-dendrite composites
Authors: Pan X.F. , Zhang H. , Zhang Z.F. , Stoica M. , He G. , Eckert J.
Published: October 2005

The compressive properties and the Vickers hardness of Cu-, Fe-, Mg-, and Zr-based monolithic bulk metallic glasses (BMGs) as well as Ti-based nanostructure-dendrite composites were investigated and compared. The monolithic BMGs exhibit nearly the same yield strength σ y and fracture strength σf but poor plasticity. The Vickers hardness HV of the monolithic BMGs follows the empirical relationship HV/3 ≈σy ≈σf. The Ti-based composites yield at a relatively low stress level (less than 850 MPa) but fail at a very high fracture stress (∼ 2 GPa) and exhibit a large strain hardening ability. Accordingly, the Vickers hardness HV of the Ti-based nanostructure-dendrite composites obeys the relationship σy <HV/3 <σf. Based on these results, the relationship between the Vickers hardness and the compressive properties of the investigated materials will be discussed by taking the yield and fracture strength (σ y and σf), the strain hardening exponent n, and the elastic and plastic energy stored upon deformation (δΕ and δP) into account.
Impurity Effects on the Environmental Stability of Powder Processed Intermetallic Alumino-Silicide Compounds
Authors: Eason P.D. , Kaufman M.J.
Published: October 2005

The evolution of nearly dense stoichiometric silicide compacts via powder processing is presented in this paper. For specific single-phase Mo(Si,Al)2 compacts, room-temperature environmental degradation, phenomenologically similar to the pesting behavior of binary MoSi2 was observed. This degradation occurs over a series of a few months and results in grain boundary decohesion, which leads to crumbling of polycrystalline compacts in air at room temperature. Auger electron spectroscopy, transmission electron microscopy, and energy dispersive spectroscopy of the boundaries revealed the presence of an array of lens-shaped particles each comprised of silicon carbide and aluminum. The reaction of these phases with atmospheric species was accelerated by the presence of humidity. The trace presence of carbon was unavoidable due to the use graphite pressing dies. Alloying additions were made to tie up carbon by forming more stable carbides while maintaining the desired matrix phase stoichiometry. The pest phenomenon and alloying remedy were proven applicable to other silicide systems through experimentation and ThermoCalc modeling.
Transmission electron microscopy and differential scanning calorimetry studies on the precipitation sequence in an Al–Mg–Si alloy: AA6022
Authors: Yassar Reza S. , Field David P. , Weiland Hasso
Published: October 2005

The precipitate sequence in a 6022 aluminum alloy was investigated by means of differential scanning calorimetry (DSC), transmission electron microscopy, and Vickers hardness measurements. The solution-treated samples were quenched and then immediately subjected to DSC and isothermal aging experiments. It was observed that in the early stages of aging there are some unknown small precipitates that form prior to the formation of β″ precipitates. Studies on isothermally aged and DSC heated samples suggest that some of the β″ needles transform during growth to lath-shaped precipitates. An alternative precipitation sequence for AA6022 is proposed.
Plastic Deformation and Mechanical Softening of Pd40Cu30Ni10P20 Bulk Metallic Glass During Nanoindentation
Authors: Concustell A. , Sort J. , Alcalá G. , Mato S. , Gebert A. , Eckert J. , Baró M.D.
Published: October 2005

Nanoindentation tests of Pd40Cu30Ni10P20 bulk metallic glass were performed over a wide range of indentation rates (from 0.04 up to 6.4 mN s−1) under the standard load control mode. New results using the feedback displacement control mode are also presented. The dependence of the pop-in formation on the loading rate is investigated. Variations in hardness and reduced elastic modulus as a function of the indentation rate are observed. A softening effect occurs when increasing the loading rate. This is explained by the differences in plastic deformation achieved at different indentation rates. The displacement control mode was used to avoid the shear localization of the free volume, leading to the almost complete absence of pop-ins along the loading curve. The obtained results suggest that plastic flow in bulk metallic glasses is governed by the rate of creation of free volume, which depends on the strain rate and its localization into shear bands.
Indentation mechanics of Cu–Be quantified by an in situ transmission electron microscopy mechanical probe
Authors: Bobji M.S. , Pethica J.B. , Inkson B.J.
Published: October 2005

In situ transmission electron microscopy was used to study, in real time, the sub-surface deformation taking place in Cu–Be alloy during nanoindentation. A twinned region of the material was indented with a sharp tungsten tip in a specially developed transmission electron microscopy (TEM) holder. A flexible hinge-based force sensor was used to measure the force on the indenter, and the force–displacement curve for the tip was obtained by tracking the tip in the sequential images of a TEM video of the indentation process. Step-like structures ∼50 nm in size resulting from the tip surface roughness were observed to generate clusters of dislocations in the sample when they come in contact with the softer Cu–Be. With this setup, the forces and the mean pressure associated with such an individual deformation event in a nanostructured TEM sample were measured.
Effects of V2O5 on the synthesis of Ba2Ti9O20 powders
Authors: Lin Huixing , Chen Wei , Luo Lan
Published: October 2005

Phase-pure Ba2Ti9O20 powders were made by doping 3 wt% of V2O5 to a Ba:Ti = 2:9 molar composition, and the effects of the dopant on the phase formation were investigated. The study shows that BaTiO3, BaTi2O5, and BaTi4O9 were the intermediate phases before the formation of Ba2Ti9O20 for samples with or without V2O5. However, with V2O5 doping, the temperature at which Ba2Ti9O20 occurred were lowered from 1150 to 1050 °C and single phase Ba2Ti9O20 powders was easily obtained at 1150 °C for 2 h. Microstructure of the powders was examined by field emission scanning electron microscopy. No evidence of V2O5–Ba2Ti9O20 solid-solution was found by x-ray diffraction and energy-dispersive spectroscopy. The benefit of V2O5 to facilitate the Ba2Ti9O20 synthesis is most probably due to a vanadium-containing eutectic liquid phase which accelerates the migration of reactant species.
Nanocrystalline GdFeO3 via the gel-combustion process
Authors: Chavan S.V. , Tyagi A.K.
Published: October 2005

Nanocrystalline GdFeO3 powder was synthesized by a combustion technique, using glycine as the fuel and the corresponding metal nitrates as oxidants. Five different molar ratios of fuel-to-oxidant were chosen to study the effect of fuel content on the phase formation and the powder properties. The powders after calcination were characterized by x-ray diffraction (XRD) and crystallite sizes calculated by x-ray line broadening. The crystallite sizes for the phase pure products after calcination at 600 °C were in the range 40–65 nm. The transmission electron microscopy observations clearly highlight the pronounced crystallinity for the propellant chemistry samples. The nature of the agglomerates was investigated by light scattering studies. The lattice thermal expansion behavior was also studied by high-temperature XRD.
Determination of elastic modulus and hardness of viscoelastic-plastic materials by instrumented indentation under harmonic load
Authors: Menčík J. , Rauchs G. , Bardon J. , Riche A.
Published: October 2005

When determining elastic modulus and hardness of viscoelastic-plastic materials by depth-sensing indentation, one must respect their specific response. In the monotonic load-unload testing mode, the unloading should be preceded by a dwell mitigating the influence of the delayed deforming. The continuous stiffness measurement (CSM) mode, with a small harmonic signal added to the basic monotonic load, enables continuous measurement of harmonic contact stiffness and mechanical properties as a function of depth. However, the contact depth and area in this mode actually depend on the slow (monotonic) component of the loading and should be determined not from the harmonic contact stiffness but from the unloading stiffness; otherwise, the calculated elastic modulus and mean contact pressure will be incorrect. This paper provides the formulae for these calculations, defines special characteristics—such as apparent dynamic hardness and the index of sensitivity to harmonic loading—and shows how to improve results by smoothing the harmonic stiffness curve. The proposed methods are illustrated through nanoindentation tests of polymethyl methacrylate.
Formation of Metallic Nanowires by Utilizing Electromigration
Authors: Saka M. , Ueda R.
Published: October 2005

A technique for forming metallic nanowires by utilizing electromigration, which is the phenomenon of atomic diffusion due to high current densities, is presented. These diffused atoms can be used for creating metallic nanowires. To specify the position at which a nanowire is formed, some specific conditions need to be established. These conditions are, first, to control the atomic diffusion so the accumulation of atoms produces the desired higher compressive stress; second, to design the structure to control the areas in which diffusion takes place; third, to adjust the thickness of the passivation layer deposited on the metal; and fourth, to form a small slot in the passivation layer through which the compressive stress is released by discharging the diffused atoms. It is shown that when these factors are satisfied, an Al nanowire can be successfully generated in a passivated metal track composed of an Al line buried in a W line.