bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chlorite in Metabasites from the Mikabu and North Chichibu Belts, Southwest Japan
Authors: Miyahara Masaaki , Kitagawa Ryuji , Uehara Seiichiro 
Published: October 2005

AbstractChlorites formed as a replacement of phenocrysts in metabasites from the pumpellyite-actinolite to lower-greenschist facies Mikabu and North Chichibu belts in southwest Japan were studied by X-ray powder diffraction, electron microprobe analysis (EMPA) and high-resolution transmission electron microscopy (HRTEM). The metabasites contain a small quantity of fine-grained smectite and corrensite in the <1 μm size fraction. The chlorite also contains trace amounts of Ca, Na and K, which generally appear to be associated with smectite stacked in chlorite packets. The smectite layers comprise up to 13% of the chlorite domains. Theoretical estimates of the smectite ratio by the Wise method using EMPA data coincide well with the ratio determined based on HRTEM observations in most chlorites. However, in some chlorites with high proportions of Ca, Na and K, the cations cannot be reasonably attributed to smectite alone. Based on the present analyses, Ca, Na and K cations are also hosted in discrete interstitial phases of fine-grained smectite and corrensite as possible retrograde metamorphic products. These findings suggest that care should be taken in application of the Wise method to estimate the smectite ratio, and that the whole-rock chlorite composition may not be suitable as a geothermometer.
Chemical and Crystallographic Properties of Kaolin from Ultisols in Thailand
Authors: Kanket Wimolnan , Suddhiprakarn Anchalee , Kheoruenromne Irb , Gilkes Robert J. 
Published: October 2005

AbstractEighteen purified kaolin samples from Thai Ultisols were studied by X-ray diffraction, X-ray fluorescence, transmission electron microscopy and BET methods. Minor amounts of inhibited vermiculite, quartz and anatase were general contaminants of the kaolins which had an average chemical composition of 403 g kg−1 Al2O3, 550 g kg−1 SiO2, 25.3 g kg−1 Fe2O3, 15.6 g kg−1 TiO2 and 4.65 g kg−1 K2O on an ignited basis. Appreciable concentrations of Mn, Co, Ni, Cu, Zn, As and Pb were present and most of the Ni, Cu and Zn in the original clay fraction was retained in the deferrated kaolin concentrate. It was not possible to determine if these elements are present as structural ions in kaolin crystals.The kaolins exhibited a variety of crystal morphologies ranging from sub-micron, euhedral, hexagonal plates to anhedral plates and tubes. Their specific surface areas ranged from 15.9 to 61.4 m2g−1 (mean 44.9 m2g−1) and surface area increased with decrease in crystal size. The cation exchange capacity of the kaolins ranged from 7.2 to 23.4 cmolc kg−1 and surface charge density from 0.16 to 0.99 C m−2 but these values are sensitive to the presence of contaminants. Structural iron ranged from 12.4 to 44.8 g kg−1 Fe2O3 and there was an increase in structural defects towards the soil surface associated with an increase in the amount of structural iron.
Alteration of Ilmenite in the Cretaceous Sandstones of Nova Scotia, Southeastern Canada
Authors: Pe-Piper Georgia , Piper David J. W. , Dolansky Lila 
Published: October 2005

AbstractMost detrital ilmenite grains in sandstones of the Chaswood Formation are completely altered to pseudorutile, leucoxene and rutile. The textural, chemical and mineralogical changes involved in alteration were tracked using electron microprobe analyses, backscattered electron images, and elemental maps. Ilmenite grains (Ti/(Ti+Fe) ≈ 0.48) alter patchily to pseudorutile (Ti/(Ti+Fe) 0.5–0.7) with volume loss, forming a porous structure and this process continues with the development of leucoxene (Ti/(Ti+Fe) 0.7–0.9). Within the pseudorutile and leucoxene, stubby prismatic rutile crystals have been precipitated. Si and A1 occur in the altered ilmenite, either (1) inherited from original quartz and muscovite inclusions in the parent crystal or (2) as kaolinite altered from muscovite inclusions or precipitated in the pore space, under pedogenic or early diagenetic conditions. Distribution of alteration phases has been related to facies and diagenetic variations. With increasing amounts of leaching in different types of paleosols, there was increasing alteration of pseudorutile to leucoxene. In light gray mudstones and interbedded sandstones with diagenetic kaolinite that formed beneath the water table from percolating meteoric water, most leucoxene was converted to rutile. Burial diagenesis (to vitrinite reflectance values >0.4%) also promoted the change from leucoxene to rutile. The alteration of ilmenite is an important source of Fe for diagenetic minerals in the Chaswood Formation and correlative offshore deltaic and marine facies of the Scotian basin.
A Simple Method for Partial Purification of Reference Clays
Authors: Arroyo L. Jacqueline , Li Hui , Teppen Brian J. , Boyd Stephen A. 
Published: October 2005

AbstractThe influence of clay preparation procedure on sorption and hydrolysis of carbaryl (1-naphthyl, A-methyl carbamate) by the reference smectite SWy-2 was examined. For research purposes, reference clays are sometimes used without purification, or more commonly, the <2 μm size fraction is obtained by gravity sedimentation or low-speed centrifugation. We determined that these common methods did not remove all the inorganic carbonate impurities present in SWy-2, and that these impurities caused alkaline conditions in aqueous clay suspensions leading to the alkaline hydrolysis of carbaryl to 1-naphthol. The hydrolytic activity of homoionic K-SWy-2 disappeared once carbonates were eliminated. Two methods were evaluated for preparing K-SWy-2 devoid of inorganic carbonates. In Method A, inorganic carbonates were first removed by incremental additions of a 0.5 M sodium acetate buffer (pH 5.0) until the clay suspension reached pH 6.8, followed by low-speed centrifugation to obtain the <2 μm size fraction; in Method B, the order of these steps was reversed. Carbaryl hydrolysis was used as a probe to determine the effectiveness of the two methods in terms of the removal of carbonate accessory minerals. Homoionic K-SWy-2 obtained by Methods A and B produced near neutral pH when suspended in water and hydrolysis of carbaryl in these suspensions was not evident. In this regard, both clay preparation methods were acceptable. However, there were procedural advantages with Method B, which is therefore recommended for the partial purification of reference clays, as detailed in this paper.
DIFFaX Simulations of Stacking Faults in Layered Double Hydroxides (LDHs)
Authors: Radha A. V. , Shivakumara C. , Kamath P. Vishnu 
Published: October 2005

AbstractCarbonate-intercalated layered double hydroxides of Co(II) and Ni(II) with Fe(III) and Al(III) were precipitated under different conditions (pH = 8–12; T= 25–80°C). All the samples are replete with stacking faults which are not eliminated by post-precipitation hydrothermal treatment (80–180°C, 18 h). DIFFaX simulations show that the layer stacking sequence of the disordered samples can be generated by a mixture of motifs corresponding to the 3R1 and 2H1 polytypes. These specific sequences are selected in preference to others because of the need for hydrogen bonding between the intercalated carbonates and hydroxide sheets. Thermodynamic considerations show that faulted crystals have greater stability than ordered crystals. Stacking faults arising from a mixture of 3R1 and 2H1 motifs, while having the same enthalpy as that of the ordered crystal, nevertheless contribute to thermodynamic stability by enhancing disorder.
Synthesis of Al-PILC Assisted by Ultrasound: Reducing the Intercalation Time and the Amount of Synthesis Water
Authors: Pérez-Zurita M. Josefina , Pérez-Quintana Gabriela J. , Hasblady Alfonso J. , Maldonado Adriana , de Navarro Caribay Urbina , De Abrisqueta Ander , Scott Carlos E. 
Published: October 2005

AbstractOf all the known pillared layered clays (PILC), Al-PILC is the most studied. In spite of that, its use on a commercial scale is not yet possible due to the large amount of water required for its synthesis. The aim of the present work was to take advantage of the beneficial effects of ultrasound radiation for reducing intercalation time, and to optimize the synthesis parameters in order to find a viable industrial means of preparing Al-PILC.A comprehensive study of the effect of ultrasonic radiation on the parameters which have a direct effect on the amount of water used in the synthesis was conducted, specifically on the effects of: (1) mmol of Al/g of clay ratio (R) by decreasing the volume of A1 solution and keeping the amount of clay constant, (2) the concentration of clay in the initial suspension (or not suspending the clay at all), and (3) the concentration of the A1 precursor solution. The use of ultrasonic radiation produced the expected reduction in exchange time which was attributed to a decrease of the clay-particle size. This decrease of particle size gave rise to an improvement in the diffusion of the A1 precursor towards the core of the clay grain leading to solids with increased surface areas, basal spacing and X-ray diffraction peak definition. By optimizing the synthesis parameters directly involved in the consumption of water, it was possible to decrease the amount used by >60%.
Effect of Cosolvents on Ca-Na Exchange onto Wyoming Bentonite
Authors: Srour Rafif K. , McDonald Louis M. 
Published: October 2005

AbstractCalcium-sodium exchange on Wyoming bentonite in methanol, ethanol and acetone-water systems were investigated at 0.03 N Cl and at room temperature. Calcium-sodium exchange isotherms were plotted at cosolvent concentrations ranging from 0 to 70% wt./wt. using Ca and Na ionic activities before and after correction for CaCl+ formation. In both cases and in all treatments, a greater selectivity of bentonite surfaces for Ca ions was observed. When compared to water, different trends were observed among and within cosolvents. These trends varied depending on whether or not CaCl+ formation was accounted for. Ignoring the formation of CaCl+, the preference of bentonite for Ca increased in methanolwater systems with increased percent methanol at low equivalent Ca fraction (<0.2). At higher Ca fractions, this preference matched that of water. In ethanol-water, no increased preference of the surface for Ca was observed. In acetone-water, increasing cosolvent concentration decreased the preference of the surface for Ca. The magnitude of this decrease was larger at low equivalent Ca fraction (<0.2). After correction for CaCl+, both in solution and on the surface, the preference of bentonite for Ca2+ was larger in methanol- and ethanol-water systems. In acetone-water, increased surface preference for Ca was only apparent at low acetone fractions (<50%). At higher acetone fractions, there was evidence of increased Na loading but no increase in Ca2+ selectivity. Clearly, ion-pair formation and its effects on Ca-Na exchange reactions cannot be ignored in mixtures of aqueous-organic solvents. After accounting for this effect, Ca-Na exchange in the studied solvents appears to be more of a surface- than a solution-controlled phenomenon that involves both electrostatic and specific solvent-surface types of interactions that have not been elucidated.
Real-time Control of ESO Adaptive Optics Systems (Echtzeitsteuerung der ESO Adaptive Optik Systeme)
Authors: Fedrigo Enrico , Kasper Markus , Ivanescu Liviu , Bonnet Henri 
Published: October 2005

Abstract
The light coming from a star travels undisturbed for billions of kilometers until it reaches the boundaries of the Earth atmosphere: there small differences in the refraction index distort the spherical wavefront, creating phase errors in the image-forming ray paths. Even at the best sites, ground-based telescopes observing at visible wavelengths cannot, because of atmospheric turbulence alone, achieve an angular resolution better than telescopes of 10- to 20-cm diameter. Adaptive Optics (AO) is a technique to remove the effects of these distortions in real-time by operating a deformable mirror that rapidly adapts its shape to the atmospheric disturbance canceling it. ESO now operates several AO systems in the Paranal observatory, where the four telescopes of the VLT (Very Large Telescope) are installed. Several of them are the result of a common project called MACAO, for Multi Application Curvature Adaptive Optics. Four MACAO systems, one for each VLT telescope, are now serving the VLT-Interferometer (VLTI) increasing the capability of the interferometer. In this paper we will present the main concept of adaptive optics and then we will derive a model for a generic AO system. We will then tailor the model to MACAO and study some interesting features of MACAO as the control of the piston mode and the control of the tip/tilt modes.
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

Abstract
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

AbstractMit 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

Abstract
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

Abstract
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

Abstract
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

Summary
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

Summary
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

Summary
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

Summary
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

Summary
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.