bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental dissolution of molybdenum‐sulphides at low oxygen concentrations: A first‐order approximation of late Archean atmospheric conditions
Authors: Greber Nicolas D. , Mäder Urs , Nägler Thomas F. 
Published: April 2015

AbstractThe abundance of atmospheric oxygen and its evolution through Earth's history is a highly debated topic. The earliest change of the Mo concentration and isotope composition of marine sediments are interpreted to be linked to the onset of the accumulation of free O2 in Earth's atmosphere. The O2 concentration needed to dissolve significant amounts of Mo in water is not yet quantified, however. We present laboratory experiments on pulverized and surface‐cleaned molybdenite (MoS2) and a hydrothermal breccia enriched in Mo‐bearing sulphides using a glove box setup. Duration of an experiment was 14 days, and first signs of oxidation and subsequent dissolution of Mo compounds start to occur above an atmospheric oxygen concentration of 72 ± 20 ppmv (i.e., 2.6 to 4.6 × 10−4 present atmospheric level (PAL)). This experimentally determined value coincides with published model calculations supporting atmospheric O2 concentrations between 1 × 10−5 to 3 × 10−4 PAL prior to the Great Oxidation Event and sets an upper limit to the molecular oxygen needed to trigger Mo accumulation and Mo isotope variations recorded in sediments. In combination with the published Mo isotope composition of the rock record, this result implies an atmospheric oxygen concentration prior to 2.76 Ga of below 72 ± 20 ppmv.
Seasonal to decadal variations of sea surface pCO2 and sea‐air CO2 flux in the equatorial oceans over 1984–2013: A basin‐scale comparison of the Pacific and Atlantic Oceans
Authors: Wang Xiujun , Murtugudde Raghu , Hackert Eric , Wang Jing , Beauchamp Jim 
Published: April 2015

AbstractThe equatorial Pacific and Atlantic Oceans release significant amount of CO2 each year. Not much attention has been paid to evaluating the similarities and differences between these two basins in terms of temporal variability. Here we employ a basin‐scale, fully coupled physical‐biogeochemical model to study the spatial and temporal variations in sea surface pCO2 and air‐sea CO2 flux over the period of 1984–2013 in the equatorial Pacific and Atlantic Oceans. The model reproduces the overall spatial and temporal variations in the carbon fields for both basins, including higher values to the south of the equator than to the north, the annual maximum sea surface pCO2 in boreal spring, and the annual peak in sea‐to‐air CO2 flux in boreal fall in the upwelling regions. The equatorial Pacific reveals a large interannual variability in sea surface pCO2, which is associated with the El Niño–Southern Oscillation. As a contrast, there is a strong seasonality but little interannual variability in the carbon fields of the equatorial Atlantic. The former is driven by the variability of dissolved inorganic carbon but the latter by sea surface temperature. Our model estimates an average sea‐to‐air CO2 flux of 0.521 ± 0.204 Pg C yr−1 for the tropical Pacific (18°S–18°N, 150°E–90°W), which is in good agreement with the observation‐based estimate (0.51 ± 0.24 Pg C yr−1). On average, sea‐to‐air CO2 flux is 0.214 ± 0.03 Pg C yr−1 in the tropical Atlantic (10°S–10°N), which compares favorably with observational estimates.
Day‐to‐day variability and solar preconditioning of thermospheric temperature over Millstone Hill
Authors: Zhang Shun‐Rong , Holt John M. , Erickson Philip J. , Goncharenko Larisa P. 
Published: April 2015

AbstractWe use a continuous 30 day incoherent scatter radar experiment at Millstone Hill in October 2002 to examine day‐to‐day thermospheric variability in exospheric temperature Tex. Solar flux and magnetic activity influences as the main driving factors for day‐to‐day variability are investigated quantitatively. Solar ultraviolet flux levels are based on the TIMED/SEE space weather product, allowing for analysis of ultraviolet flux‐Tex correlation. Tex is most sensitive to solar EUV flux with approximately a 2 day delay at wavelengths of 27–34 nm (including 30.4 nm). In particularly, a 20–60 h time delay occurs in Tex response to EUV flux at 27–34 nm band, with shorter delays in the morning and longer delays in the afternoon and at night. The 1 ∼ 2 day delayed Tex response to solar ultraviolet flux and associated thermospheric solar preconditioning (“memory”) are most significant in the daily mean for the 27–34 nm band, in the diurnal and semidiurnal amplitudes for the soft X‐ray flux at 0.1–7 nm, and in the diurnal amplitude for longer wavelengths. An empirical model driven only by EUV flux at 27–34 nm from 2 days in advance reproduces 90% of the observed variability in the Tex daily mean. With a 2 day time delay, solar X‐ray flux at 0.1–7 nm is correlated positively with Tex diurnal amplitude and negatively with Tex semidiurnal amplitude. Finally, magnetic activity control, as represented by the Dst index, is weaker during the day and stronger at night and is important for the semidiurnal amplitude but not important for the daily mean.
Structure of the Koyna‐Warna Seismic Zone, Maharashtra, India: A possible model for large induced earthquakes elsewhere
Authors: Catchings R. D. , Dixit M. M. , Goldman M. R. , Kumar S. 
Published: April 2015

AbstractThe Koyna‐Warna area of India is one of the best worldwide examples of reservoir‐induced seismicity, with the distinction of having generated the largest known induced earthquake (M6.3 on 10 December 1967) and persistent moderate‐magnitude (>M5) events for nearly 50 years. Yet, the fault structure and tectonic setting that has accommodated the induced seismicity is poorly known, in part because the seismic events occur beneath a thick sequence of basalt layers. On the basis of the alignment of earthquake epicenters over an ~50 year period, lateral variations in focal mechanisms, upper‐crustal tomographic velocity images, geophysical data (aeromagnetic, gravity, and magnetotelluric), geomorphic data, and correlation with similar structures elsewhere, we suggest that the Koyna‐Warna area lies within a right step between northwest trending, right‐lateral faults. The sub‐basalt basement may form a local structural depression (pull‐apart basin) caused by extension within the step‐over zone between the right‐lateral faults. Our postulated model accounts for the observed pattern of normal faulting in a region that is dominated by north‐south directed compression. The right‐lateral faults extend well beyond the immediate Koyna‐Warna area, possibly suggesting a more extensive zone of seismic hazards for the central India area. Induced seismic events have been observed many places worldwide, but relatively large‐magnitude induced events are less common because critically stressed, preexisting structures are a necessary component. We suggest that releasing bends and fault step‐overs like those we postulate for the Koyna‐Warna area may serve as an ideal tectonic environment for generating moderate‐ to large‐ magnitude induced (reservoir, injection, etc.) earthquakes.
Magnetic anisotropy in rhyolitic ignimbrite, Snake River Plain: Implications for using remanent magnetism of volcanic rocks for correlation, paleomagnetic studies, and geological reconstructions
Authors: Finn David R. , Coe Robert S. , Kelly Henry , Branney Michael , Knott Thomas , Reichow Marc 
Published: April 2015

AbstractIndividual ignimbrite cooling units in southern Idaho display significant variation of magnetic remanence directions and other magnetic properties. This complicates paleomagnetic correlation. The ignimbrites are intensely welded and exhibit mylonite‐like flow banding produced by rheomorphic ductile shear during emplacement, prior to cooling below magnetic blocking temperatures. Glassy vitrophyric lithologies commonly have discrepantly shallow remanence directions rotated closer to the orientation of the subhorizontal shear fabric when compared to the microcrystalline center of the same cooling unit. To investigate this problem, we conducted a detailed paleomagnetic and rock magnetic study of a vertical profile through a single ignimbrite cooling unit and its underlying baked soil. The results demonstrate that large anisotropy of thermal remanent magnetization correlates with large (up to 38°) deflections of the stable remanence direction. Anisotropy of magnetic susceptibility revealed no strong anisotropy. A strong lineation and deflection of the remanence declination suggest that rheomorphic shear above magnetic blocking temperatures is the dominant mechanism controlling the formation of the magnetic fabric, with compaction contributing to a lesser extent. Nucleation and growth of anisotropic fine‐grained magnetite in volcanic glass at high temperatures after, and perhaps also during, emplacement is indicated by systematic variation of magnetic properties from the quickly chilled ignimbrite base to the interior. These properties include remanence directions, anisotropy, coercivity, susceptibility, strength of natural remanent magnetization, and dominant unblocking temperature. The microcrystalline ignimbrite center has a magnetic direction that is the same as the underlying baked soil and, therefore, is a more reliable recorder of the paleofield direction than the glassy margins of highly welded ignimbrites.
Wave power variability and trends across the North Atlantic influenced by decadal climate patterns
Authors: Bromirski Peter D. , Cayan Daniel R. 
Published: April 2015

AbstractClimate variations influence North Atlantic winter storm intensity and resultant variations in wave energy levels. A 60 year hindcast allows investigation of the influence of decadal climate variability on long‐term trends of North Atlantic wave power, PW, spanning the 1948–2008 epoch. PW variations over much of the eastern North Atlantic are strongly influenced by the fluctuating North Atlantic Oscillation (NAO) atmospheric circulation pattern, consistent with previous studies of significant wave height, Hs. Wave activity in the western Atlantic also responds to fluctuations in Pacific climate modes, including the Pacific North American (PNA) pattern and the El Niño/Southern Oscillation. The magnitude of upward long‐term trends during winter over the northeast Atlantic is strongly influenced by heightened storm activity under the extreme positive phase of winter NAO in the early 1990s. In contrast, PW along the United States East Coast shows no increasing trend, with wave activity there most closely associated with the PNA. Strong wave power “events” exhibit significant upward trends along the Atlantic coasts of Iceland and Europe during winter months. Importantly, in opposition to the long‐term increase of PW, a recent general decrease in PW across the North Atlantic from 2000 to 2008 occurred. The 2000–2008 decrease was associated with a general shift of winter NAO to its negative phase, underscoring the control exerted by fluctuating North Atlantic atmospheric circulation on PW trends.
High‐resolution mapping of two large‐scale transpressional fault zones in the California Continental Borderland: Santa Cruz‐Catalina Ridge and Ferrelo faults
Authors: Legg Mark R. , Kohler Monica D. , Shintaku Natsumi , Weeraratne Dayanthie S. 
Published: April 2015

AbstractNew mapping of two active transpressional fault zones in the California Continental Borderland, the Santa Cruz‐Catalina Ridge fault and the Ferrelo fault, was carried out to characterize their geometries, using over 4500 line‐km of new multibeam bathymetry data collected in 2010 combined with existing data. Faults identified from seafloor morphology were verified in the subsurface using existing seismic reflection data including single‐channel and multichannel seismic profiles compiled over the past three decades. The two fault systems are parallel and are capable of large lateral offsets and reverse slip during earthquakes. The geometry of the fault systems shows evidence of multiple segments that could experience throughgoing rupture over distances exceeding 100 km. Published earthquake hypocenters from regional seismicity studies further define the lateral and depth extent of the historic fault ruptures. Historical and recent focal mechanisms obtained from first‐motion and moment tensor studies confirm regional strain partitioning dominated by right slip on major throughgoing faults with reverse‐oblique mechanisms on adjacent structures. Transpression on west and northwest trending structures persists as far as 270 km south of the Transverse Ranges; extension persists in the southern Borderland. A logjam model describes the tectonic evolution of crustal blocks bounded by strike‐slip and reverse faults which are restrained from northwest displacement by the Transverse Ranges and the southern San Andreas fault big bend. Because of their potential for dip‐slip rupture, the faults may also be capable of generating local tsunamis that would impact Southern California coastlines, including populated regions in the Channel Islands.
Subglacial Lake CECs: Discovery and in situ survey of a privileged research site in West Antarctica
Authors: Rivera Andrés , Uribe José , Zamora Rodrigo , Oberreuter Jonathan 
Published: April 2015

AbstractWe report the discovery and on‐the‐ground radar mapping of a subglacial lake in Antarctica, that we have named Lake CECs (Centro de Estudios Científicos) in honor of the institute we belong to. It is located in the central part of the West Antarctic Ice Sheet, right underneath the Institute Ice Stream and Minnesota Glacier ice divide, and has not experienced surface elevation changes during the last 10 years. The ratio between the area of the subglacial lake and that of its feeding basin is larger than those for either subglacial lakes Ellsworth or Whillans, and it has a depth comparable to that of Ellsworth and greater than that of Whillans. Its ice thickness is ∼600 m less than that over Ellsworth. The lake is very likely a system with long water residence time. The recent finding of microbial life in Lake Whillans emphasizes the potential of Subglacial Lake CECs for biological exploration.
Combined analysis of soil moisture measurements from roving and fixed cosmic ray neutron probes for multiscale real‐time monitoring
Authors: Franz Trenton E. , Wang Tiejun , Avery William , Finkenbiner Catherine , Brocca Luca 
Published: April 2015

AbstractSoil moisture partly controls land‐atmosphere mass and energy exchanges and ecohydrological processes in natural and agricultural systems. Thus, many models and remote sensing products continue to improve their spatiotemporal resolution of soil moisture, with some land surface models reaching 1 km resolution. However, the reliability and accuracy of both modeled and remotely sensed soil moisture require comparison with ground measurements at the appropriate spatiotemporal scales. One promising technique is the cosmic ray neutron probe. Here we further assess the suitability of this technique for real‐time monitoring across a large area by combining data from three fixed probes and roving surveys over a 12 km × 12 km area in eastern Nebraska. Regression analyses indicated linear relationships between the fixed probe averages and roving estimates of soil moisture for each grid cell, allowing us to derive an 8 h product at spatial resolutions of 1, 3, and 12 km, with root‐mean‐square error of 3%, 1.8%, and 0.9%.
Estimation of mesoscale thermospheric wind structure using a network of interferometers
Authors: Harding Brian J. , Makela Jonathan J. , Meriwether John W. 
Published: April 2015

AbstractWe introduce a technique for estimating the regional thermospheric wind field from measurements made by a network of interferometers. Unlike previous work, this technique does not make assumptions about the functional form of the wind field and instead uses inverse theory to find the smoothest wind field that agrees with the measurements. This technique is general and applies to any network making radial velocity measurements. We show reconstructions of the thermospheric wind field over the eastern United States and over eastern Brazil, using data from two distinct networks of Fabry‐Perot interferometers measuring the Doppler shift of the 630.0 nm airglow emission. In Brazil, we find direct evidence of a convergent wind field during the period of rapid thermospheric temperature increase associated with the equatorial midnight temperature maximum.
Topside equatorial ionospheric density, temperature, and composition under equinox, low solar flux conditions
Authors: Hysell D. L. , Milla M. A. , Rodrigues F. S. , Varney R. H. , Huba J. D. 
Published: April 2015

AbstractWe present observations of the topside ionosphere made at the Jicamarca Radio Observatory in March and September 2013, made using a full‐profile analysis approach. Recent updates to the methodology employed at Jicamarca are also described. Measurements of plasma number density, electron and ion temperatures, and hydrogen and helium ion fractions up to 1500 km altitude are presented for 3 days in March and September. The main features of the observations include a sawtooth‐like diurnal variation in ht, the transition height where the O+ ion fraction falls to 50%, the appearance of weak He+ layers just below ht, and a dramatic increase in plasma temperature at dawn followed by a sharp temperature depression around local noon. These features are consistent from day to day and between March and September. Coupled Ion Neutral Dynamics Investigation data from the Communication Navigation Outage Forecast System satellite are used to help validate the March Jicamarca data. The SAMI2‐PE model was able to recover many of the features of the topside observations, including the morphology of the plasma density profiles and the light‐ion composition. The model, forced using convection speeds and meridional thermospheric winds based on climatological averages, did not reproduce the extreme temperature changes in the topside between sunrise and noon. Some possible causes of the discrepancies are discussed.
Basic Consideration
Authors: Wong Y.S. , Chan C.C. , Nazir Samir 
Published: April 2015

AbstractWith ever tightening regulations regarding fuel economy and emissions, hybrid electric vehicles (HEVs) are expected to comprise a larger portion of vehicle sales using various technologies to reduce fuel consumption. These vehicles have been on the market for over a decade, yet new vehicle models continue to see advances. The internal combustion engine (ICE) has low thermal and mechanical efficiencies and much of the energy of the fuel is dissipated as heat. AnHEVis designed to boost up efficiency of the vehicle drivetrain with integration of the electric propulsion system.HEVdevelopment is driven by advances inICEsimproving combustion with the aid of automotive electronics and by the development of an advanced electric drive and its optimized integration withICE. This chapter discusses features of micro, mild, full, and plug‐inHEVswith the emphasis on functionality of the electrical powertrain.HEVsare classified into series, parallel, series–parallel, and complex hybrids according to the drivetrain topology. This chapter also discusses novelty and energy management strategies of these drivetrains.
Energy Management System ofHEVs
Authors: Abe Shinichi 
Published: April 2015

AbstractThe purpose of energy management in a hybrid electric vehicle (HEV) is to maximize vehicle fuel efficiency. There are two main methods for improving fuel efficiency: managing the energy of the hybrid propulsion system and energy management on a vehicle level. In terms of the hybrid propulsion system, it is necessary to both improve the efficiency of the components and optimize the control strategy between the hybrid propulsion system and the vehicle level systems. From a vehicle level standpoint, efficiency can be improved by reducing energy losses, such as engine idling requests (e.g., by the air conditioner compressor), or by utilizing thermal energy from engine exhaust gas. This chapter will explain these two methods using the Toyota Hybrid System (THS) and integrated motor assist (IMA) system as examples. In addition, this chapter briefly explains the plug‐in hybrid vehicle system, which is likely to be installed in environmentally friendly vehicles in the future.
Steel Processing: Formability of Steel Sheets and Tailor‐Welded Blanks for Automotive Applications
Authors: Bandyopadhyay Kaushik , Panda Sushanta K. 
Published: April 2015

AbstractIn recent decades, great improvements have been made in the production of steel sheets with high formability. Automotive companies are using various grades of steels to meet the customers' ever‐changing demands for low cost and fuel efficient vehicles. Applications of advanced high strength steel and tailored blank technology in stamping of various components are a major boost for steel manufacturers, and hence, steel sheets remain the fair choice for automotive body part fabrication as compared to aluminum and magnesium sheets. In this chapter, various sheet metal‐forming processes and formability diagnostic measures such as limiting drawing ratio, limiting dome height, forming limit diagram were discussed with respect to constitutive properties of the sheet metal, damage model, and design modifications in toolings and blank shape. Emphasis is placed on application of finite element method‐basedCAE(computer‐aided engineering) techniques to predict forming behavior of various steel sheets and tailor‐welded blanks while selecting the right materials for stamping the automotive body components.
Vehicle Safety, Functional Safety,OBDDiagnosis
Authors: Kriso Stefan , Klauda Matthias , Hamann Reinhold 
Published: April 2015

AbstractWith a significantly increasing number of electrical and electronic systems within road vehicles, the complexity of such systems dramatically increases. To prevent these increasingly complex systems from becoming more and more fault‐prone is one of the most important challenges of the future. Systems have to be intrinsically safe whereby owing to the cost pressure within the automotive industry, it is not possible just to double or triple the systems, as it is usual in the avionics industry. This chapter describes the general concept of vehicle safety—especially with regard to functional safety that came into focus within recent years with the advent of a new standard for functional safety of road vehicles—theISO26262.This chapter gives an overview over the trends why safety of road vehicles becomes more and more important in future, what are the special constraints of the automotive industry. Furthermore, we explain the legal point of view and the key concept ofISO26262, for example, the method of hazard analysis and risk assessment, the concept ofSEooC(safety element out of context), the confidence in the use of software tools, and the random hardware faults and hardware metrics. Some side issues of vehicle safety such as the quality assurance concept and theOBD(on‐board diagnosis) are described.
Semiconductor Sensor (1)—Sensors for Power Trains
Authors: Hanzawa Keiji , Nakabayashi Kenji , Yasukawa Akio , Igarashi Shinya , Hoshika Hiroaki 
Published: April 2015

Abstract

This chapter explains microelectromechanical system (
MEMS
) airflow sensor and semiconductor pressure sensor. Sensing principles, manufacturing processes, possible problems for automotive applications, and their preventive actions are described.
Body
ECU
(Airbag)
Authors: Noguchi Takashi 
Published: April 2015

Abstract

An airbag is a device that protects the occupants of a vehicle at the time of a collision. The airbag
ECU
(electronic control unit) determines when a collision is occurring and deploys the airbags in the vehicle. This chapter describes the phenomena behind collision determination, details of crash testing, and explains the relevant sensing technologies. This chapter also presents details about sensors for airbags, the
ECU
, the component parts of the airbag
ECU
, and the collision determination algorithm.