bluuebunny/crossref_metadata_2025_split huggingface dataset:
Geomorphic comparison of two Atlantic coastal rivers: Toward an understanding of physical controls on Atlantic salmon habitat
Authors: Wilkins B. C. , Snyder N. P. 
Published: February 2010

AbstractRiver channel substrate size and mobility are important to Atlantic salmon spawning and rearing success. We compare morphology and bed sediment between two North American Atlantic coastal streams (Narraguagus River, Maine, USA and Jacquet River, New Brunswick, Canada). The watersheds have similar drainage areas and mean annual precipitation, but differing relief structure, channel longitudinal profiles and numbers of returning salmon. The lower‐relief Narraguagus River is segmented into steeper (gradient >0.002) and flatter reaches (gradient <0.0005). Flat reaches, including mainstem lakes, act as sediment sinks, preventing the continuity of downstream sediment transport. Based on field measurements, the Narraguagus River has a larger high‐flow width to depth ratio than the Jacquet River, but this difference is principally the result of outliers from low‐gradient channel reaches. Measurements of substrate grain size reveal finer river‐bed sediments on the Narraguagus River, however, Shields parameter calculations indicate that bed sediment should be mobile during high flows in both streams. We use the Shields equation to predict grain size based on channel slope, width and drainage area measured from digital elevation models (DEM) and aerial photographs. Predictions of median grain size agree with field measurements within a factor of 2 for 62–70% of the survey stations. We suggest ways that model misfits may provide opportunities to prioritize reach‐based restoration efforts. Based on expected grain size, we estimate 62% spawning and 68% rearing habitat along the length of the Narraguagus River, and 28 and 95% respectively on the Jacquet. Overall, glacial history and relief structure appear to be the first‐order controls on substrate grain size and habitat quality in these two rivers. Copyright © 2010 John Wiley & Sons, Ltd.
Mathematical Modelling of Water Sampler Filling
Authors: Zhang Z. , Tilliander A. , Jönsson P. G. 
Published: February 2010

AbstractSteel samples taken from ladles or tundishes during the steel making process can be of significant importance when monitoring the inclusion size and distribution. In order to preserve the original size and distributions of inclusions in the extracted samples, it is important to avoid their collisions and coagulations inside samplers during filling. Thus, it is necessary to investigate the flow during a sampling process to make sure that this is minimized. In addition, it is important to study the turbulence characteristics, since it is known to influence the inclusion growth. This study presents mathematical modelling of sampler filling using water as a media and experimental results for verification. The study focuses on a lollipop‐shaped sampler since it is one of the most common in the industry. The sampler is filled from an inlet pin located at the bottom centre of the main body. In addition, two different turbulence models, the realizable k‐ε model and Wilcox k‐ω model, were used to study the flow pattern in the sampler. The predictions were compared to experimental results obtained by Particle Image Velocimetry (PIV) measurements. It was found that the flow field predictions using the Wilcox k‐ω model agreed best with the flow field obtained by PIV measurements. Furthermore, it was illustrated that the Wilcox k‐ω model can be used for predictions of the different flow regions as well as the positions of the centres of vortexes which are located near the free surface. Thus, it is concluded that the Wilcox k‐ω model can be used in the future to predict the filling of steel samplers.
Experimental and Morphological Investigations of the Reduction from Coarse Hematite to Magnetite and Wüstite under Fluidized Bed Conditions
Authors: Weiss B. , Sturn J. , Voglsam S. , Strobl S. , Mali H. , Winter F. , Schenk J. 
Published: February 2010

AbstractFor optimization of iron ore fines reduction processes, fundamental knowledge of the reduction kinetics under industrial operating conditions is required. Reduction tests with coarse hematite iron ore were performed in H2‐rich reduction gas atmospheres of H2, H2O, CO, CO2 and CH4 considering elevated pressures similar to industrial process conditions. The reaction kinetics of the reactions hematite to magnetite, magnetite to wüstite and hematite to wüstite were investigated in a laboratory‐scale pressurized fluidized bed reactor. To facilitate kinetic measurements, the laboratory‐scale fluidized bed reactor is equipped with a sampling system, which allows sampling of the bed material at operating conditions. Process conditions were chosen close to industrial plants in a temperature range from 400 to 700 °C. Significant influence of temperature on the rate of reduction was found in all tests. Variation of reduction gas composition showed no influence on the rate of reduction in the range of concentrations investigated. Results presented herein proved the feasibility of depicting industrial process conditions in laboratory scale. For the reduction of hematite to magnetite and magnetite to wüstite topochemical phase growth were observed. In the single step reduction of hematite to wüstite, magnetite appeared as intermediate product formed by topochemical reaction while progressive conversion of magnetite to wüstite was found.
Simulation of Solidification Microstructure and Columnar to Equiaxed Transition in Free‐cutting Steel 9SMn28 based on a CAFE Method
Authors: Wang J. , Wang F. , Li C. , Zhang J. 
Published: February 2010

AbstractThe solidification microstructure in 9SMn28 free‐cutting steel is simulated by the finite element – cellular automaton (CAFE) method based on the calculation of convection in a casting. The simulation results are consistent with experimental findings; the simulated crystallisation process conforms to the actual situation. The solidification of 9SMn28 alloy is a volume solidification mode under slow cooling condition. The columnar‐to‐equiaxed transition (CET) is also studied in the CAFE model. The mechanism of the CET in the CAFE model is thermal interaction. The CET is not abrupt but occurs gradually, the long columnar grains are first blocked by elongated grains. The grains become more equiaxed as the thermal gradient is decreased with the development of solidification.
Possibility of Selective Oxidation of Vanadium from Iron and Phosphorus in Fe‐V‐P Melt
Authors: Lindvall M. , Rutqvist E. , Ye G. , Björkvall J. , Sichen Du 
Published: February 2010

AbstractExperiments on a vanadium recovery method from vanadium containing BOF‐slag using both a Tamman furnace (3 kg scale) and an induction furnace (150 kg scale) were conducted. The vanadium was extracted into the slag phase by bubbling oxidation gas into a metal bath consisting mainly of V (1–10 mass%), Si (less than 1 mass%) and P (about 1 mass%). The first experiments revealed that the slag formed during oxidation reaction had considerably high phosphate capacity. High phosphorus content would rule out the possibility of using the slag as a raw material for the production of ferrovanadium of high quality. In order to reduce the P‐content in the slag, addition of slag former to reduce phosphate capacity was necessary. A suitable slag system (having the initial composition 40 mass% Al2O3 ‐ 25 mass% CaO ‐ 35 mass% SiO2) and a suitable atmosphere, by using CO2, that enhanced the oxidation of vanadium, but limit the oxidation of iron and phosphorus was found. However, more efforts should be put forward, e.g. study of the phase diagram, the viscosity of the slag and even oxide activities to gain more insight into the slag formed by selective oxidation.
Geh‐ und Radwegbrücke über den Stadtkanal in Brandenburg an der Havel
Authors: Reck Peter , Andrä Hans‐Peter , Häberle Uwe 
Published: February 2010

AbstractIm Rahmen von Stadtentwicklungsmaßnahmen wird vor dem St. Pauli‐Kloster in Brandenburg an der Havel eine neue Gehund Radwegbrücke über den Stadtkanal errichtet. Das integrale Stahlrahmenbauwerk mit einer Gesamtlänge von 40,50 m ist das Ergebnis eines begrenzt offenen Gestaltungswettbewerbs.Bridge for footpath and cycle track across the urban canal in Brandenburg an der Havel, Germany. In the context of urban development, a new pedestrian bridge across the Stadtkanal is planned in the city of Brandenburg an der Havel. The steel frame bridge with the total length of 40,50 m is the result of a competition.
Die dritte Brücke über den Orinoco/Venezuela – Eine zweistöckige Schrägkabelbrücke für Straße und Eisenbahn mit Verbundfachwerk
Authors: Saul Reiner , Humpf Karl , Schiele Ingo 
Published: February 2010

AbstractDie dritte Brücke über den Orinoco verbindet die Orte Cabruta, Provinz Guárico, im Norden und Caicara del Orinoco, Provinz Bolivar, im Süden und hat eine Schlüsselstellung in der weiteren Erschließung Venezuelas, insbesondere der Gebiete südlich des Orinoco. Die kombinierte Straßen‐ und Eisenbahnbrücke hat eine Gesamtlänge von 11125 m. Die doppelstöckige Hauptbrücke mit einer Länge von 2280 m und Regelstützweiten von 120 m hat eine seilverspannte Hauptöffnung von 360 m. Der Überbau ist ein Verbundfachwerk mit einer Gesamthöhe von rund 12 m. Die diamantenförmigen Pylone haben eine Höhe von 182,5 m und werden auf 39 Großbohrpfählen mit einem Durchmesser von 2,5 m und einer Länge von 80 m gegründet. Der Überbau wird in 60 m Schüssen mit Pontons zur Baustelle transportiert, dort zu 360 m langen Einheiten zusammengebaut und auf Teflon‐Lagern eingeschoben, hierzu sind temporäre Verstärkungen erforderlich. Das 120 m lange und 2400 t schwere Schlussstück der Schrägkabelbrücke wird eingeschwommen und mit Litzenhebern gehoben.The third bridge across the Orinoco River/Venezuela – A doubledeck bridge cable‐stayed bridge for highway and railroad with composite truss girder. With the aim of developing the Southwest of Venezuela and to enable its connections with the rest of the country, a third bridge over the Orinoco River was designed between the cities of Cabruta, State of Guárico, in the north and Caicara del Orinoco, State of Bolivar, in the south. The combined highway and railroad bridge will have a total length of 11125 km. The stay‐cable main bridge with 360 m main span and the adjacent approach bridges with a length of 2 · 720 m are comprised of a steel composite truss girder with a depth of 12,0 m. The diamond shaped pylons are founded on piles with a diameter of 2,5 m and a length of up to 80 m. The bridge is transported to the site on barges in lengths of 60 m and assembled in construction yards adjacent to the southern and northern abutments to elements of 360 m, before launching each into its final position using Teflon plates on top of the piers; this requires temporary strengthening. The center segment of the main bridge with a length of 120 m and a dead weight of 2400 t will be lifted from a barge.
Neubau der Elbebrücke Schönebeck – Entwurf, Ausschreibung und Vergabe
Authors: Eilzer Wolfgang , Portius Meike , Morawietz Markus , Stockmann Rico , Heymel Ulrich 
Published: February 2010

AbstractIm Zuge der Ortsumgehung Schönebeck der Bundesstraße B 246a wird der Neubau einer Brücke über die Elbe erforderlich. Der folgende Aufsatz behandelt die im Rahmen der Entwurfsplanung untersuchten Varianten des 1128,50 m langen Bauwerkes und geht auf die weitere Planung bis zur Vergabe ein. Kernstück der neuen Elbequerung ist die einhüftige Schrägseilbrücke mit einer Hauptspannweite von 185 m.The new Elbe Bridge Schönebeck – design, bidding procedure and allocation. The following article describes the studies and the design of the new roadwaybridge across the river Elbe near the City of Schönebeck, Germany. The new bridge will have a total length of 1128,50 m and a main span of 185 m built as a single tower cable‐stayed bridge.
Eine Erweiterung der Verallgemeinerten Technischen Biegetheorie zur Erfassung von Scheibenschubverzerrungen
Authors: Hanf Manfred 
Published: February 2010

AbstractEs wird eine Erweiterung der VTB vorgestellt, mit deren Hilfe Membranschubverzerrungen erfasst werden können. Nach einem Überblick über Grundlagen und Bezeichnungsweise der schubstarren Faltwerkstheorie werden die Ansätze für die Erweiterung, die Einführung kinematischer Schubkorrekturen sowie zusätzliche Wölbfreiheitsgrade an Nebenknoten, dargestellt. Die hierfür erforderlichen Modifikationen bei der Querschnittswerteberechnung werden beschrieben. Das beherrschende Differentialgleichungssystem wird aufgestellt. Mit Hilfe eines Potenzreihenansatzes gelingt die quasi‐geschlossene Lösung unter Angabe von Stabsteifigkeitsmatrizen und Partikularlösungen. Den Abschluss bilden Vergleichsrechnungen mit konkurrierenden Verfahren beziehungsweise Versuchen.An extension of the Generalized Beam Theory to determinate plate shear lags. An extension of the GBT which includes membrane shear lags is introduced. After giving an overview of the basics and terminology of the shear rigid folded plate theory, the approach for the extension, including the implementation of kinematic shear corrections as well as additional warping degrees of freedom on secondary nodes, are shown. The modifications of the calculation of cross section values necessary therefore are described. The differential equation is solved by using power series which leads to a quasi‐closed solution with indication of stiffness matrices and particulate solutions. As conclusion, comparisons with competing methods and experiments are presented.
Buckled Bridges Using Film Stress for Three‐Dimensional Structures: Effects of Lateral Designs on Vertical Profiles and Dynamic Characteristics
Authors: Sasaki Minoru , Hane Kazuhiro , Briand Danick , Noell Wilfried , de Rooij Nicolaas F. 
Published: February 2010

AbstractBridges buckled by film stress can generate a vertical displacement resulting in three‐dimensional structures. We have demonstrated a micromirror lifted by buckled bridges and a vertical comb drive actuator. The structures show rounded profiles in a stable manner. The detailed profiles of the bridges and the lifted micromirrors are examined. The relations between the lateral design and its effect on the vertical profile and the dynamic characteristics are studied. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Vacuum Packaging Technology for Uncooled Infrared Sensor
Authors: Kimata Masafumi , Tokuda Takayuki , Tsuchinaga Akinobu , Matsumura Takeshi , Abe Hideyuki , Tokashiki Naotaka 
Published: February 2010

AbstractWe developed vacuum packaging equipment and low‐cost vacuum packaging technology for the mass production of uncooled infrared focal plane arrays (IRFPAs). The equipment consists of two chambers with identical construction. Two‐chamber architecture provides flexibility in the vacuum packaging process, so we can bake the components and achieve getter activation by heating, stem/cap soldering, and cap/window soldering in a series under high‐vacuum conditions. Heaters and component‐holding jigs are designed to assure rapid and uniform heating to 500°C. The batch size is 27 if we choose a 15‐mm diameter TO8 package and can be increased by enlarging the heater area. We also developed a micro‐vacuum gauge to evaluate the vacuum level in encapsulated packages. The operation principle of this vacuum gauge is based on thermal conduction by air molecules. It can be integrated in IRFPA chips since the fabrication process is compatible with that for IRFPAs. We encapsulated the vacuum gauges in TO8 packages with our vacuum packaging equipment, and confirmed that the pressure in fabricated packages is sufficiently low for high‐performance IRFPA operation (≪1 Pa). Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Individual Generator Modeling in Multimachine Networks and Its Stabilization with SVCs
Authors: Zhou Jun 
Published: February 2010

AbstractIndividual generators with damping windings and shunt static VAR compensators (SVCs) and under disturbances in multimachine power networks are modeled via what we call the model‐reference (MR) swing equations. Then stabilization of individual generators is contrived with nonlinear and MR SVCs, by employing the MR swing equations. The SVCs guarantee robust stability against disturbances and uncertainties in generators and from connecting networks, and they can be implemented in a variety of ways. As a specific example, nonlinear and piecewise SVCs are suggested, which can accommodate performances on generators such as swing reduction ratio. Examples illustrate efficacy of the stabilization technique. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
An Experimental Study on Relative Displacement Sensing Using Phototransistor Array for Building Structures
Authors: Kanekawa Kiyoshi , Matsuya Iwao , Sato Maya , Tomishi Ryota , Takahashi Motoichi , Miura Satoru , Suzuki Yasutsugu , Hatada Tomohiko , Katamura Ryuta , Nitta Yoshihiro , Tanii Takashi , Shoji Shuichi , Nishitani Akira , Ohdomari Iwao 
Published: February 2010

AbstractWe propose a novel sensor for directly measuring the relative displacement of a building structure. The sensor is composed of a laser light source and a phototransistor (PT) array. The PT array is immobilized on the floor together with a photo scattering plate made of glass, whereas the laser light source is separately immobilized on the ceiling. The photo scattering plate is placed in front of the PT array and distributes the laser beam on the multiple PTs. The relative displacement between the ceiling and the floor is estimated by the distribution of the PT output voltages, and the displacement is estimated with a resolution finer than the interval between the PTs. The accuracy of the relative displacement sensor (RDS) is experimentally assessed by conducting a shaking table test exhibiting several waves from harmonic sinusoidal waves to real seismic waves. We discuss the feasibility of real‐time monitoring system utilizing this sensor. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Performance modeling of MPEG‐4 video streaming over IEEE 802.11 using distribution coordination function
Authors: Lin Cheng‐Han , Chilamkurti Naveen K. , Zeadally Sherali , Shieh Ce‐Kuen 
Published: February 2010

AbstractDelivering video streaming over wireless Internet is becoming increasingly popular. However, most of the research studies focused on the modeling analysis of system performance such as saturation throughput and channel utilization. Perceived quality of video streaming cannot be assessed solely based on the results of analytical models. In this paper, we propose a model to assess the perceived quality of MPEG‐4 video streaming over IEEE 802.11 distribution coordination function (DCF)‐based wireless local area networks. The analysis of our proposed model considers not only effects of losses such as collision loss from channel access competition but also wireless loss caused by wireless interferences. Moreover, the impact of the loss of specific MPEG‐4 video frames is also taken into account in the performance analysis. The model was validated by comparing our performance results with results obtained from simulation and analytical models. The results show that our proposed model is able to predict the perceived quality of MPEG‐4 video streaming over DCF‐based WLAN more accurately than other models. Copyright © 2010 John Wiley & Sons, Ltd.
Dynamic hybrid duplex for rate maximization in OFDMA
Authors: Oh Sangmin , Lee Chae Y. 
Published: February 2010

AbstractOrthogonal frequency division multiple access (OFDMA) is considered as one of the technologies for 4th generation (4G) due to its robustness against multi‐path environment. OFDMA also has the advantage of flexibility in resource allocation, which cannot be supported by existing duplex schemes. In this paper, we propose dynamic hybrid duplex (DHD) which will enhance the efficiency and flexibility of the OFDMA system. To establish the framework of resource allocation for the DHD, we formulate DHD resource allocation problem (DRAP) which maximizes the total users' data rate with power, rate, and subcarrier allocation constraints. A heuristic procedure is developed to solve the problem. The procedure finds the best mode and the best amount of resources allocated to downlink (DL) and uplink (UL). Simulation is performed with five scenarios to evaluate the DHD. Its results show that the proposed DHD outperforms other duplex schemes in various environments. Copyright © 2010 John Wiley & Sons, Ltd.
Site‐directed mutagenesis of Asp853 in Pdr3p transcriptional activator from Saccharomyces cerevisiae
Authors: Dzugasova Vladimira , Borecka Silvia , Batova Monika , Pilisiova Ruzena , Hervayova Nora , Subik Julius 
Published: February 2010

AbstractThe PDR3 gene encodes one of the main transcriptional activators involved in the control of multidrug resistance in the yeast Saccharomyces cerevisiae. Recently, it has been demonstrated that a specific D853Y mutation results in the loss of transactivation activity of Pdr3p and its conversion to multicopy suppressor of multidrug resistance. In this study, the Asp853 in Pdr3p was replaced by eight different amino acids and the function of mutated proteins was analysed. Different levels of complementation of cycloheximide hypersensitivity and expression of autoregulated PDR3 and its PDR5 target in the pdr1Δpdr3Δ mutant strain, ranging from that of the wild‐type to loss‐of‐function alleles, were observed in pdr3 mutants containing Pro, Glu, Arg, Asn, Ser, Leu, Phe, Ile or Tyr instead of Asp853 in Pdr3p. The introduction of the D853Y mutation into gain‐of‐function Pdr3p suppressed the transcription of the PDR3 and PDR5 genes and reduced both the rhodamine 6G efflux rate and the drug resistance level in corresponding double mutants. The results indicate that, while Pdr3p can tolerate several substitutions of Asp853, the occurrence of a hydrophobic amino acid at this position has an adverse effect on its function. Copyright © 2010 John Wiley & Sons, Ltd.
The Yap family and its role in stress response
Authors: Rodrigues‐Pousada Claudina , Menezes Regina A. , Pimentel Catarina 
Published: February 2010

AbstractThe budding yeast Saccharomyces cerevisiae possesses a very flexible and complex programme of gene expression when exposed to several environmental challenges. Homeostasis is achieved through a highly coordinated mechanism of transcription regulation involving several transcription factors, each one acting singly or in combination to perform specific functions. Here, we review our current knowledge of the function of the Yap transcription factors in stress response. They belong to b‐ZIP proteins comprising eight members with specificity at the DNA‐binding domain distinct from that of the conventional yeast AP‐1 factor, Gcn4. We finish with new insights into the links of transcriptional networks controlling several cellular processes. The data reviewed in this article illustrate how much our comprehension of the biology of Yap family involved in stress response has advanced, and how much research is still needed to unravel the complexity of the role of these transcriptional factors. The complexities of these regulatory interactions, as well as the dynamics of these processes, are important to understand in order to elucidate the control of stress response, a highly conserved process in eukaryotes. Copyright © 2010 John Wiley & Sons, Ltd.