bluuebunny/crossref_metadata_2025 huggingface dataset:
The Design and Development of a 15 kV SiC Half-Bridge Multi-Chip Power Module for Medium Voltage Applications
Authors: Cole Z. , Stabach J. , Falling G. , Killeen P. , McNutt T. , Passmore B. S.
Published: October 2015

In this work, the packaging design and development of a high voltage (> 15 kV), high current (120 A) silicon carbide (SiC) multi-chip power module (MCPM) will be presented. The module implements a MCPM packaging strategy which itself uses subassemblies to reduce manufacturing costs through reworkability. The use of solderless internal connections aids in reducing cost both by simplifying the assembly process as well as enabling a high level of flexibility in the manufacturing process in order to drive down costs by increasing yield. A wire bondless flip-chip die interconnection scheme has been developed in parallel with a more traditional wire bonded method. Both presented approaches utilize a common set of parts with minimal differences due to the divergent portions of each interconnection scheme. Device neutrality in this design ensures that a variety of die types from any manufacturer may be housed in a number of arrangements depending on the requirements of the end-use application without requiring significant redesign effort for each new application or improvement in device technology. The SiC MCPM is constructed using high temperature capable materials, enabling operation at high junction temperatures. This leads to the ability to design a small, low profile module with low parasitic inductances and a small junction to case thermal resistance. A low module thermal resistance makes it possible to significantly reduce the size and complexity of the cooling systems, ultimately, reducing the size of the system. Thus, this novel high voltage SiC MCPM represents a significant step forward in high voltage switching applications. This paper discusses the overall mechanical design of the SiC high voltage MCPM; the three-dimensional finite-element modeling and analysis of the thermal and electrical characteristics of the high voltage power module are also presented.
Interconnect and Packaging Techniques for System Integration of High Power Assemblies that Improve Assembly Efficiency and Design Flexibility
Authors: Lynch Joseph , Schneider Richard , Longford Andy
Published: October 2015

Growth in electrification and power conversion is driving a large need for electrical efficiency and improved cost models that in theory can be gained through the design consolidation of secondary assemblies into complete single modules. To put this theory into practice, there must be a cost effective way to interconnect these subassemblies that is space efficient, easy to assemble, supports high power and is resilient to temperature cycles.

To integrate subassemblies cost effectively is to develop them so that they have interconnects between each subassembly that are an integral part of the subassembly itself and are not secondary add on or bolt on connector systems. Additionally these interconnects must be easily pluggable, to allow assembly methods that are manufacturing friendly, measureable and don't require secondary heating methods.

This paper will show how proven highly reliable interconnects like press-fit, IDC and wirebonds can be integrated into subassemblies along with capacitors, motors, DBC power substrates, thermal coolers, heats sinks, busbars and other subassemblies typically found in power assemblies, to create a cost effective design that provides flexibility in manufacturing assembly with measureable results.
Reliability of Cu Wirebonded ICs for Automotive Applications
Authors: McLeish Jim , Caswell Greg , Schueller Randy
Published: October 2015

The transition to replace gold with copper bond wires in semiconductor components, primarily driven by the ever increasing price of gold wire, has been under way for several years. Cu wire bonds (Cu-WBs) are technically more challenging than gold to produce, requiring improved designs, processes and equipment. After introduction in consumer products, their use is now migrating to automotive electronics where product integrity for quality, reliability and durability (QRD) and safety over 10–15 years in a demanding harsh environment is paramount, in addition to managing cost in the highly competitive global automotive market.

Reliability issues with some Cu wire bonded components detected during the rigorous product validation durability–reliability tests of automotive electronics, however, are starting to appear. The indications are that only optimized package design with well-controlled assembly processes are suitable for high reliability (hi-rel) harsh environment applications such as automotive, military and aerospace. A concern is that non-optimized Cu-WBs and package materials issues are being detected in module-level durability validation tests in parts that were qualified as automotive grade per AEC Q-100 or AEC-Q101. This paper will explore the issues and discuss potential solutions as the Automotive Electronics Council (AEC) – the organization that defines requirements for automotive grade electronic components – works to update qualification procedures for evolving Cu-wire bond technology.
Automate 3D Modeling of Trace and Via Structures
Authors: Caswell Greg , Hillman Craig , Blattau Nathan , Navius Frank Pitelli , Waters Paul , Sharon Gil
Published: October 2015

The simulation and modeling of advanced packaging has always been hindered by the duality of the design process. Electrical design packages are based on vectors, plotting, and routing compounds that align well with the physical process of fabricating substrates. However, these design files contain numerous flaws and limitations that does not allow them to be directly imported into modern CAE tools for mechanical, thermal, and electrical modeling and simulation. The resulting gap results in extended model development (physical artifacts are recreated in the CAE software), gross assumptions about composite properties, or a preference for physical testing. This limitation does not align with the strategic goals of the semiconductor packaging industry, especially in regards to the system-in-package and package-on-package technologies. This paper will discuss a new parsing methodology developed to extract trace, via, and ground plots from standard electronic CAD output formats (Gerber, ODB++, ODB.xml). The methodology for capturing trace geometry and eliminating design flaws and singularities will be explained. The process includes selection of appropriate elements for trace, via, power plane, epoxy, and solder mask to ensure successful automesh completion and segmented hole creation and checking to ensure compatibility with model development strategies implemented in Abaqus and Ansys software packages. Identification of material properties through rule checks and computation of effective properties using sandwich and Halpern-Tsai equations will be demonstrated. The presentation will conclude with a discussion on case studies where automated 3D modeling of all copper features provides strong advantages over existing processes, including warpage prediction of wafers, strips, and packages, effective CTE calculations, and high frequency electrical signal simulations.
Developing Enterprise Skills in Undergraduate Medical Students: A Mixed-methods Evaluation
Authors: Dube Sharul , Underwood Sarah , Murdoch-Eaton Deborah
Published: October 2015

Introduction

Support for the development of enterprise skills in medical education exists from the perspectives of educators, researchers, and healthcare leaders. However, literature is limited evaluating the understanding of medical students about these skills. This study aimed to determine whether medical students valued gaining enterprise skills within the course and those skills that they identified and recognized contributed to enterprise practice in subsequent training.

Methodology

Quantitative and qualitative evaluations were undertaken for over three years. Students completed end-of-course evaluations ( n = 895) in 2011 and 2012, responding to closed questions utilizing a Likert scale. Subsequent qualitative reflections were collected by interviews one year later with nine students and eight supervisors.

Results

Immediately after course completion, students gave positive feedback, identifying the development of independent learning, creativity, and reflection, as these enterprise skills were most valued. However, in subsequent reflection one year later, they were unable to transfer the acquired knowledge and identify the examples of enterprise around them in their later experiences and had mixed beliefs about its value in medicine.

Conclusion

Enterprise skills need to be revisited explicitly throughout the medical curriculum, with authentic real-life examples, to sustain students' understanding about the role of enterprise in medicine.
The vertical structure of cloud radiative heating over the Indian subcontinent during summer monsoon
Authors: Johansson E. , Devasthale A. , L'Ecuyer T. , Ekman A. M. L. , Tjernström M.
Published: October 2015

Abstract. Clouds forming during the summer monsoon over the Indian subcontinent affect its evolution through their radiative impact as well as the release of latent heat. While the latter is previously studied to some extent, comparatively little is known about the radiative impact of different cloud types and the vertical structure of their radiative heating/cooling effects. Therefore, the main aim of this study is to partly fill this knowledge gap by investigating and documenting the vertical distributions of the different cloud types associated with the Indian monsoon and their radiative heating/cooling using the active radar and lidar sensors onboard CloudSat and CALIPSO. The intraseasonal evolution of clouds from May to October is also investigated to understand pre-to-post monsoon transitioning of their radiative heating/cooling effects. The vertical structure of cloud radiative heating (CRH) follows the northward migration and retreat of the monsoon from May to October. Throughout this time period, stratiform clouds radiatively warm the middle troposphere and cool the upper troposphere by more than ±0.2 K day−1 (after weighing by cloud fraction), with the largest impacts observed in June, July and August. During these months, the fraction of high thin cloud remains high in the tropical tropopause layer (TTL). Deep convective towers cause considerable radiative warming in the middle and upper troposphere, but strongly cool the base and inside of the TTL. This cooling is stronger during active (−1.23 K day−1) monsoon periods compared to break periods (−0.36 K day−1). The contrasting radiative warming effect of high clouds in the TTL is twice as large during active periods than in break periods. These results highlight the increasing importance of CRH with altitude, especially in the TTL. Stratiform (made up of alto- and nimbostratus clouds) and deep convection clouds radiatively cool the surface by approximately −100 and −400 W m−2 respectively while warming the atmosphere radiatively by about 40 to 150 W m−2. While the cooling at the surface induced by deep convection and stratiform clouds is largest during active periods of monsoon, the importance of stratiform clouds further increases during break periods. The contrasting CREs (cloud radiative effects) in the atmosphere and at surface, and during active and break periods, should have direct implications for the monsoonal circulation.
PM2.5 water-soluble elements in the southeastern United States: automated analytical method development, spatiotemporal distributions, source apportionment, and implications for heath studies
Authors: Fang T. , Guo H. , Verma V. , Peltier R. E. , Weber R. J.
Published: October 2015

Abstract. Water-soluble redox-active metals are potentially toxic due to its ability to catalytically generate reactive oxygen species (ROS) in vivo, leading to oxidative stress. As part of the Southeastern Center for Air Pollution and Epidemiology (SCAPE), we developed a method to quantify water-soluble elements, including redox-active metals, from a large number of filter samples (N = 530) in support of the center's health studies. PM2.5 samples were collected during 2012–2013 at various sites (three urban, two rural, a near-road site, and a road-side site) in the southeastern United States, using high-volume samplers. Water-soluble elements (S, K, Ca, Ti, Mn, Fe, Cu, Zn, As, Se, Br, Sr, Ba, and Pb) were determined by extracting filters in deionized water and re-aerosolized for analyses by X-ray fluorescence (XRF) using an online aerosol element analyzer (Xact, Cooper Environmental). Concentrations ranged from detection limits (nominally 0.1 to 30 ng m−3) to 1.2 μg m−3, with S as the most abundant element, followed by Ca, K, Fe, Cu, Zn, and Ba. Positive matrix factorization (PMF) identified four factors that were associated with specific sources based on relative loadings of various tracers. These include brake/tire wear (with tracers Ba and Cu), biomass burning (K), secondary formation (S, Se, and WSOC), and mineral dust (Ca). Of the four potentially toxic and relatively abundant metals (redox-active Cu, Mn, Fe, and redox-inactive Zn), 51 % of Cu, 32 % of Fe, 17 % of Mn, and 45 % of Zn were associated with the brake/tire factor. Mn was mostly associated with the mineral dust factor (45 %). Zn was found in a mixture of factors, with 26 % associated with mineral dust, 14 % biomass burning, and 13 % secondary formation. Roughly 50 % of Fe and 40 % of Cu were apportioned to the secondary formation factor, likely through increases in the soluble fraction of these elements by sulfur-driven aerosol water and acidity. Linkages between sulfate and water-soluble Fe and Cu may account for some of the past observed associations between sulfate/sulfur oxide and health outcomes. For Cu, Mn, Fe, and Zn, only Fe was correlated with PM2.5 mass (r = 0.73–0.80). Overall, mobile source emissions generated through mechanical processes (re-entrained road dust, tire and break wear) and processing by secondary sulfate were major contributors to water-soluble metals known to be capable of generating ROS.
Observations of new particle formation in enhanced UV irradiance zones near cumulus clouds
Authors: Wehner B. , Werner F. , Ditas F. , Shaw R. A. , Kulmala M. , Siebert H.
Published: October 2015

Abstract. During the CARRIBA (Cloud, Aerosol, Radiation and tuRbulence in the trade wInd regime over BArbados) campaign, the interaction between aerosol particles and cloud microphysical properties was investigated in detail, which also includes the influence of clouds on the aerosol formation. During two intensive campaigns in 2010 and 2011, helicopter-borne measurement flights were performed to investigate the thermodynamic, turbulent, microphysical, and radiative properties of trade-wind cumuli over Barbados. During these flights, 91 cases with increased aerosol particle number concentrations near clouds were detected. The majority of these cases are also correlated with enhanced irradiance in the ultraviolet (UV) spectral wavelength range. This enhancement reaches values up to a factor of 3.3 greater compared to background values. Thus, cloud boundaries provide a perfect environment for the production of precursor gases for new particle formation. Another feature of cloud edges is an increased turbulence, which may also enhance nucleation and particle growth. The observed events have a mean length of 100 m, corresponding to a lifetime of less than 300 s. This implies that particles with diameters of at least 7 nm grew several nanometers per minute, which corresponds to the upper end of values in the literature (Kulmala et al., 2004). Such high values cannot be explained by sulfuric acid alone; thus extremely low volatility organic compounds (ELVOCs) are probably involved here.
Constraining condensed-phase formation kinetics of secondary organic aerosol components from isoprene epoxydiols
Authors: Riedel T. P. , Lin Y.-H. , Zhang Z. , Chu K. , Thornton J. A. , Vizuete W. , Gold A. , Surratt J. D.
Published: October 2015

Abstract. Isomeric epoxydiols from isoprene photooxidation (IEPOX) have been shown to produce substantial amounts of secondary organic aerosol (SOA) mass and are therefore considered a major isoprene-derived SOA precursor. Heterogeneous reactions of IEPOX on atmospheric aerosols form various aerosol-phase components or "tracers" that contribute to the SOA mass burden. A limited number of the reaction rate constants for these acid-catalyzed aqueous-phase tracer formation reactions have been constrained through bulk laboratory measurements. We have designed a chemical box model with multiple experimental constraints to explicitly simulate gas- and aqueous-phase reactions during chamber experiments of SOA growth from IEPOX uptake onto acidic sulfate aerosol. The model is constrained by measurements of the IEPOX reactive uptake coefficient, IEPOX and aerosol chamber wall-losses, chamber-measured aerosol mass and surface area concentrations, aerosol thermodynamic model calculations, and offline filter-based measurements of SOA tracers. By requiring the model output to match the SOA growth and offline filter measurements collected during the chamber experiments, we derive estimates of the tracer formation reaction rate constants that have not yet been measured or estimated for bulk solutions.
Wind speed response of marine non-precipitating stratocumulus clouds over a diurnal cycle in cloud-system resolving simulations
Authors: Kazil J. , Feingold G. , Yamaguchi T.
Published: October 2015

Abstract. Observed and projected trends in large scale wind speed over the oceans prompt the question: how might marine stratocumulus clouds and their radiative properties respond to future changes in large scale wind speed? Wind speed drives the surface fluxes of sensible heat, moisture, and momentum, and thereby acts on cloud liquid water path (LWP) and cloud radiative properties. We present an investigation of the dynamical response of non-precipitating, overcast marine stratocumulus clouds to different wind speeds, all else equal. In cloud-system resolving simulations, we find that higher wind speed leads to faster boundary layer growth and stronger entrainment. The dynamical driver is enhanced buoyant production of turbulence kinetic energy (TKE) from latent heat release in cloud updrafts. LWP is enhanced during the night and in the morning at higher wind speed, and more strongly suppressed later in the day. Wind speed hence accentuates the diurnal LWP cycle by expanding the morning – afternoon contrast. The higher LWP at higher wind speed does not, however, enhance cloud top cooling because in clouds with LWP ⪆ 50 g m−2, long wave emissions are very insensitive to LWP. This leads to the more general conclusion that in sufficiently thick stratocumulus clouds, additional boundary layer growth and entrainment due to a boundary layer moistening arises by stronger production of TKE from latent heat release in cloud updrafts, rather than from enhanced longwave cooling. We find furthermore that large scale wind modulates boundary layer decoupling. At nighttime and at low wind speed during daytime, it enhances decoupling in part by faster boundary layer growth and stronger entrainment, and in part because circulation driven by shear from large scale wind in the sub-cloud layer hinders vertical moisture transport between the surface and cloud base. With increasing wind speed, however, in decoupled daytime conditions, shear-driven circulation due to large scale wind takes over from buoyancy-driven circulation in transporting moisture from the surface to cloud base, and thereby reduces decoupling and helps maintain LWP. The cloud radiative effect (CRE) responds to changes in LWP and cloud fraction, and higher wind speed translates to a stronger diurnally averaged CRE. However, the sensitivity of the diurnally averaged CRE to wind speed decreases with increasing wind speed.
On the interpretation of the loading correction of the aethalometer
Authors: Virkkula A. , Chi X. , Ding A. , Shen Y. , Nie W. , Qi X. , Zheng L. , Huang X. , Xie Y. , Wang J. , Petäjä T. , Kulmala M.
Published: October 2015

Abstract. Aerosol optical properties were measured with a seven-wavelength aethalometer and a three-wavelength nephelometer at the suburban site SORPES in Nanjing, China, in September 2013–January 2015. The aethalometer compensation parameter k, calculated with the Virkkula et al. (2007) method depended on the backscatter fraction, measured with an independent method, the integrating nephelometer. At λ = 660 nm the daily averaged compensation parameter k ≈ 0.0017 ± 0.0002 and 0.0042 ± 0.0013 when backscatter fraction at λ = 635 nm was in the ranges of 0.100 ± 0.005 and 0.160 ± 0.005, respectively. Also, the wavelength dependency of the compensation parameter depended on the backscatter fraction: when b(λ = 525 nm) was less than approximately 0.13 the compensation parameter decreased with wavelength and at larger b it increased with wavelength. This dependency has not been considered in any of the algorithms that are currently used for processing aethalometer data. The compensation parameter also depended on the single-scattering albedo ω0 so that k decreased with increasing ω0. For the green light (λ = 520 nm) in the ω0 range 0.870 ± 0.005, the average (± standard deviation) k ≈ 0.0047 ± 0.006 and in the ω0 range 0.960 ± 0.005, k ≈ 0.0028 ± 0.0007. This difference was larger for the near-infrared light (λ = 880 nm): in the ω0 range 0.860 ± 0.005, k ≈ 0.0055 ± 0.0023 and in the ω0 range 0.960 ± 0.005, k ≈ 0.0019 ± 0.0011. The negative dependence of k on ω0 was also shown with a simple theoretical analysis.
Measurements of greenhouse gases at Beromünster tall tower station in Switzerland
Authors: Berhanu T. A. , Satar E. , Schanda R. , Nyfeler P. , Moret H. , Brunner D. , Oney B. , Leuenberger M.
Published: October 2015

Abstract. In order to constrain the regional flux of greenhouse gases, an automated measurement system was built on an old radio tower at Beromünster, Switzerland. The measurement system has been running since November 2012 as part of the Swiss greenhouse gases monitoring network (CARBOCOUNT-CH), which is composed of four measurement sites across the country. The Beromünster tall tower has five sampling lines with inlets at 12.5, 44.6, 71.5, 131.6 and 212.5 m a.g.l., and it is equipped with a Picarro CRDS analyzer (G-2401), which continuously measures CO, CO2, CH4 and H2O. Sensors for detection of wind speed and direction, air temperature, barometric pressure, and humidity have also been installed at each height level. We have observed a non-negligible temperature effect in the calibration measurements, which was found to be dependent on the type of cylinder (steel or aluminum) as well as trace gas species (strongest for CO). From a target gas of known mixing ratio that has been measured once a day, we have calculated a long-term reproducibility of 2.79, 0.05 and 0.29 ppb for CO, CO2 and CH4, respectively over 19 months of measurements. The values obtained for CO2 and CH4 are compliant with the WMO recommendations, while the value calculated for CO is higher than the recommendation, which is mainly due to the above mentioned temperature effects.
Inverse transport modeling of volcanic sulfur dioxide emissions using large-scale ensemble simulations
Authors: Heng Y. , Hoffmann L. , Griessbach S. , Rößler T. , Stein O.
Published: October 2015

Abstract. An inverse transport modeling approach based on the concepts of sequential importance resampling and parallel computing is presented to reconstruct altitude-resolved time series of volcanic emissions, which often can not be obtained directly with current measurement techniques. A new inverse modeling and simulation system, which implements the inversion approach with the Lagrangian transport model Massive-Parallel Trajectory Calculations (MPTRAC) is developed to provide reliable transport simulations of volcanic sulfur dioxide (SO2). In the inverse modeling system MPTRAC is used to perform two types of simulations, i. e., large-scale ensemble simulations for the reconstruction of volcanic emissions and final transport simulations. The transport simulations are based on wind fields of the ERA-Interim meteorological reanalysis of the European Centre for Medium Range Weather Forecasts. The reconstruction of altitude-dependent SO2 emission time series is also based on Atmospheric Infrared Sounder (AIRS) satellite observations. A case study for the eruption of the Nabro volcano, Eritrea, in June 2011, with complex emission patterns, is considered for method validation. Meteosat Visible and InfraRed Imager (MVIRI) near-real-time imagery data are used to validate the temporal development of the reconstructed emissions. Furthermore, the altitude distributions of the emission time series are compared with top and bottom altitude measurements of aerosol layers obtained by the Cloud–Aerosol Lidar with Orthogonal Polarization (CALIOP) and the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) satellite instruments. The final transport simulations provide detailed spatial and temporal information on the SO2 distributions of the Nabro eruption. The SO2 column densities from the simulations are in good qualitative agreement with the AIRS observations. Our new inverse modeling and simulation system is expected to become a useful tool to also study other volcanic eruption events.
Coupled dynamic model and vibration responses characteristic of a motor-driven flexible manipulator system
Authors: Liu Y. F. , Li W. , Yang X. F. , Wang Y. Q. , Fan M. B. , Ye G.
Published: October 2015

Abstract. Motor-driven flexible manipulator systems (MDFMSs) are widely used in industry robot fields. During the dynamic modeling, the separate investigation method which neglects the dynamic behavior of the driving motor will cause an error in the dynamic analysis of the flexible manipulator, especially with high-speed operations. This paper proposes a coupled dynamic model of the MDFMS in which the driving motor and flexible manipulator are considered as an integrated system, which can clearly reflect the influence of the dynamic effect of the driving motor. Based on the proposed dynamic model, the vibration responses of the flexible manipulator under different velocities, accelerations and structure parameters, as well as the effect mechanism of the driving motor on the vibration responses, are investigated. The results obtained in this paper contribute to the structure design, motion optimization and dynamic analysis of flexible manipulators.
Approaches for delineating landslide hazard areas using receiver operating characteristic in an advanced calibrating precision soil erosion model
Authors: Ghazvinei P. T. , Zandi J. , Ariffin J. , Hashim R. B. , Motamedi S. , Aghamohammadi N. , Moghaddam D. A.
Published: October 2015

Abstract. Soil erosion is undesirable natural event that causes land degradation and desertification. Identify the erosion-prone areas is a major component of preventive measures. Recent landslide damages at different regions lead us to develop a model of the erosion susceptibility map using empirical method (RUSLE). A landslide-location map was established by interpreting satellite image. Field observation data was used to validate the intensity of soil erosion. Further, a correlation analysis was conducted to investigate the "Receiver Operating Characteristic" and frequency ratio. Results showed a satisfactory correlation between the prepared RUSLE-based soil erosion map and actual landslide distribution. The proposed model can effectively predict the landslide events in soil-erosion area. Such a reliable predictive model is an effective management facility for the regional landslide forecasting system.
River bulge evolution and dynamics in a non-tidal sea – Daugava River plume in the Gulf of Riga, Baltic Sea
Authors: Soosaar E. , Maljutenko I. , Uiboupin R. , Skudra M. , Raudsepp U.
Published: October 2015

Abstract. Satellite remote sensing imagery and numerical modelling were used for the study of river bulge evolution and dynamics in a non-tidal sea, the Gulf of Riga (GoR) in the Baltic Sea. Total suspended matter (TSM) images showed a clearly formed anti-cyclonically rotating river bulge from Daugava River discharge during the studied low wind period. In about 7–8 days the bulge grew up to 20 km in diameter, before being diluted. Bulge growth rate was estimated as rb ~ t 0.31± 0.23 (R2 = 0.87). A high resolution (horizontal grid step of 125 m) General Estuarine Transport Model (GETM) was used for detailed description of the development of the river plume in the southern GoR over the period when satellite images were acquired. In the model simulation, the rb ~ t 0.5± 0.04 (R2 = 0.90). Both the model simulation and the satellite images showed that river water was mainly contained in the bulge and there were numerous intrusions at the outer perimeter of the bulge. We made numerical sensitivity tests with actual bathymetry and measured river runoff without wind forcing: (1) having initial 3-dimensional density distribution, (2) using initially a homogeneous ambient density field. In the first case, the anti-cyclonic bulge did not develop within the course of the model simulation and coastal current was kept offshore due to ambient density-driven circulation. In the second case, the river plume developed steadily into an anti-cyclonically recirculating bulge and a coastal current. This showed a significant effect of the wind in the evolution of the river bulge, even if the wind speed was moderate (3–4 m s−1). In the second case, rb ~ t 0.28± 0.01 (R2 = 0.98). While previous studies conclude that mid-field bulge region is governed by balance between centrifugal, Coriolis and pressure gradient terms, our study showed that geostrophic balance is valid for the entire mid-field of the bulge. In addition, while there is discharge into the homogenous GoR in case of high inflow Rossby number, the river inflow might split into two jets, with strong mixing zone in-between, in the plume near field region.
The hydrothermal power of oceanic lithosphere
Authors: Grose C. J. , Afonso J. C.
Published: October 2015

Abstract. We have estimated the power of ventilated hydrothermal heat transport, and its spatial distribution, using a set of recently developed plate models which highlight the effects of axial hydrothermal circulation and thermal insulation by oceanic crust. Testing lithospheric cooling models with these two effects, we estimate that global advective heat transport is about 6.6 TW, significantly lower than most previous estimates, and that the fraction of that extracted by vigorous circulation on the ridge axes (< 1 My old) is about 50 % of the total, significantly higher than previous estimates. These new estimates originate from the thermally insulating properties of oceanic crust in relation to the mantle. Since the crust is relatively insulating, the effective properties of the lithosphere are "crust dominated" near ridge axes (a thermal blanketing effect yielding lower heat flow) and gradually approach mantle values over time. Thus, cooling models with crustal insulation predict low heat flow over young seafloor, implying that the difference of modeled and measured heat flow is due to the heat transport properties of the lithosphere, in addition to ventilated hydrothermal circulation as generally accepted. These estimates may bear on important problems in the physics and chemistry of the Earth because the magnitude of ventilated hydrothermal power affects chemical exchanges between the oceans and the lithosphere, thereby affecting both thermal and chemical budgets in the oceanic crust and lithosphere, the subduction factory, and the convective mantle.
A new approach to over-bedding in American healthcare: Statistical analysis and computer simulation of patient admission in a West Virginia state psychiatric hospital
Authors: Zheng Wanhong , Li Minqi , Nickasch Michael , Yang Feng , Gohar Aida Rabiee
Published: October 2015

Objective: To identify the factors that have a substantial impact on a West Virginia state psychiatric hospital’s bed occupancy by investigating historical admission data, and developing a computer simulation system to give insight into modifiable variables that reduce admission numbers, therefore to provide solutions to the over-bedding problem.Methods: Quantitative review of hospital admission data from January 2007 to November 2013 allowed for the construction of a simulation model to estimate the inpatient flow. The system’s performance was evaluated after alteration of selected parameters and variables.Results: The study revealed significant regional differences in admission numbers. The civil commitments and psychiatric hospitalizations do not directly correlate with county coverage populations. Some counties sent disproportionately more patients. Patients’ length of stay also varied among geographical areas. Re-admission was not uncommon. Using the percentage of diversion as the outcome measurement, the computer simulation model reconstructed the admission scenario multiple times, predicting that the diversion rate can be significantly reduced if certain variables (hospital capacity, patient arrivals from top referring counties, and patient length of stay) are changed.Conclusions: Involuntary admissions were unevenly distributed according to geography and population in the studied American state psychiatric hospital. Using historical data, computer simulations can model hospital admission systems to evaluate performance and predict needs for change.
Digital Literacies and Generational Micro-Cultures: Email Feedback in Lebanon
Authors: Coursey Christina De , Dandashly Nadine
Published: October 2015

This study reports on the introduction of email feedback, in a private university in Lebanon with marked generational differences and a traditional instructor culture focused on grammar correction. The instructor profile showed insufficient ELT training and a disjuncture between those with low and those with long service. Instructors were trained, and an email form used during one semester. A survey elicited instructors’ views. Appraisal analysis identified attitudes in personal responses written by students and instructors. Analysis of feedback quality was undertaken. Results showed students responded positively, instructors negatively to email feedback. Instructors perceived students’ positive response, but reasserted traditional understandings of teacher roles, reflecting a lack of understanding of the role of emotion in acquiring form. Training in ELT and digital literacies, management oversight of accountability structures, and sufficient remuneration for part-timers’ grading hours, are recommended. The study also implicates long years of service in resistance to needed change.
The Effective of Computer-Assisted Instruction Based on Top-Level Structure Method in English Reading and Writing Abilities of Thai EFL Students
Authors: Jinajai Nattapong , Rattanavich Saowalak
Published: October 2015

This research aims to study the development of ninth grade students’ reading and writing abilities and interests in learning English taught through computer-assisted instruction (CAI) based on the top-level structure (TLS) method. An experimental group time series design was used, and the data was analyzed by multivariate analysis of variance (MANOVA) with repeated measures as well as basic statistical and line graphs. The results demonstrate that the experimental group attained significantly higher development in English reading and writing at the .001 level and registered significantly higher interests at the .01 level.
Virtual R&D Teams: A New Model for Product Development
Authors: Ebrahim Nader Ale
Published: October 2015

Increased global competitions have urged small and medium enterprises (SMEs) to develop new products faster. Virtual research and development (RD) teams in SMEs can offer a solution to speed up time-to-market of new product development (NPD). However, factors that affect the effectiveness of virtual teams for NPD are still not adequately verified. This paper presents the correlations between virtual RD team constructs and virtual team effectiveness by developing a “Virtual Research and Development Team” (ViRDT) model. The items, which may influence the effectiveness of virtual teams, are taken from the literature. Through an online survey and by application of structural equation modeling (SEM) technique, the proposed model (ViRDT) has been tested. The results suggest that the process construct is strongly correlated to the effectiveness of virtual teams. Therefore, NPD managers in virtual RD teams should concentrate on the process of new product development rather than simply equipping the teams with the latest technology or employing highly qualified experts. Further empirical research is recommended to fully explore and appreciate the breadth of application of the ViRDT model.Virtual Ramp;D Teams: A New Model for Product Development
Transbronchial Cryobiopsies in the Evaluation of Lung Allografts: Do the Benefits Outweigh the Risks?
Authors: Roden Anja C. , Kern Ryan M. , Aubry Marie Christine , Jenkins Sarah M. , Yi Eunhee S. , Scott John P. , Maldonado Fabien
Published: October 2015

Transbronchial cryobiopsy technique yields larger biopsies with enhanced quality. The benefits and safety of cryobiopsies have not been thoroughly studied in lung allografts.Context.—

To compare size, quality, reproducibility of interpretation of rejection and complications of cryobiopsies with those of conventional biopsies from lung allografts.Objective.—

All cryobiopsies (March 2014–January 2015) of lung allografts performed at Mayo Clinic, Rochester, and medical records were reviewed. For comparison, conventional biopsies from the same patient or, if unavailable, from a random patient, were selected. Two pathologists blinded to outcome reviewed all biopsies. Specimen volume, number of alveoli, small airways, and pulmonary vessels were counted and statistically compared.Design.—

Fifty-four biopsies (27 cryobiopsies) from 18 patients (11 men) were reviewed. A median of 3 (range, 2–5) and 10 (range, 6–12) specimens were obtained with cryobiopsies and conventional biopsies, respectively. Cryobiopsies were larger and contained more alveoli (P < .001, both) and small airways (P = .04). Conventional biopsies showed more fresh alveolar hemorrhage (procedural) and crush artifact/atelectasis (P < .001, both). Cryobiopsies contained more pulmonary veins and venules (P < .001). There was no significant difference between the types of biopsies with respect to the reviewers' agreement on grades of rejection. Complications were more frequent in the cryobiopsy group, though the difference was not statistically significant.Results.—

Cryobiopsies of lung allografts are larger and have less artifact. However, complications occur and should be considered. Three cryobiopsy specimens appear sufficient for histopathologic evaluation of lung allografts.Conclusions.—
Maritime Performing Party under the Rotterdam Rules 2009
Authors: Mandić Nikola , Skorupan Wolf Vesna
Published: October 2015

This paper explores the provisions of the Rotterdam Rules 2009 relating to the performing party in general and the maritime performing party in particular. Performing party means a person who performs or undertakes to perform any of the carrier’s obligations under a contract of carriage with respect to the receipt, loading, handling, stowage, carriage, keeping, care, unloading or delivery of the goods, to the extent that such person acts, either directly or indirectly, at the carrier’s request or under the carrier’s supervision or control. Maritime performing party means a performing party who performs or undertakes to perform any of the carrier’s obligations during the period between the arrival of goods at the port of loading and their departure from the port of discharge of a ship. The maritime performing party is a new concept introduced by the Rotterdam Rules. The central intention of this paper is to study and analyse the concept, legal standing and liability of a maritime performing party under the Rotterdam Rules. A comparative analysis of the legal standing of persons analogous to the performing party in conventions regulating the carriage of goods by sea is also provided.
An alternate approach to ensemble ENSO forecast spread: Application to the 2014 forecast
Authors: Larson Sarah M. , Kirtman Ben P.
Published: October 2015

Evaluating the 2014 El Niño forecast as a “bust” may be tapping into a bigger issue, namely that forecast “overconfidence” from single‐model ensembles could affect the retrospective assessment of El Niño–Southern Oscillation (ENSO) predictions. The present study proposes a new approach to quantifying an “expected” spread and uncertainty from noise‐driven processes and supplementing these measures with actual ENSO forecasts. Expanding on a previously developed coupled model framework that isolates noise‐driven ENSO‐like errors, an experimental design is implemented to generate an expected December Niño‐3.4 spread from March initial condition sea surface temperature errors that have similar structure to the 2014 and 2015 observed. Results reveal that the 2014 ENSO forecast falls within the expected uncertainty generated by ENSO‐independent, forecast‐independent, noise‐driven errors.
Impact of sample geometry on the measurement of pressure‐saturation curves: Experiments and simulations
Authors: Moura M. , Fiorentino E.‐A. , Måløy K. J. , Schäfer G. , Toussaint R.
Published: October 2015

In this paper, we study the influence of sample geometry on the measurement of pressure‐saturation relationships, by analyzing the drainage of a two‐phase flow from a quasi‐2‐D random porous medium. The medium is transparent, which allows for the direct visualization of the invasion pattern during flow, and is initially saturated with a viscous liquid (a dyed glycerol‐water mix). As the pressure in the liquid is gradually reduced, air penetrates from an open inlet, displacing the liquid which leaves the system from an outlet on the opposite side. Pressure measurements and images of the flow are recorded and the pressure‐saturation relationship is computed. We show that this relationship depends on the system size and aspect ratio. The effects of the system's boundaries on this relationship are measured experimentally and compared with simulations produced using an invasion percolation algorithm. The pressure build up at the beginning and end of the invasion process are particularly affected by the boundaries of the system whereas at the central part of the model (when the air front progresses far from these boundaries), the invasion happens at a statistically constant capillary pressure. These observations have led us to propose a much simplified pressure‐saturation relationship, valid for systems that are large enough such that the invasion is not influenced by boundary effects. The properties of this relationship depend on the capillary pressure thresholds distribution, sample dimensions, and average pore connectivity and its applications may be of particular interest for simulations of two‐phase flow in large porous media.
Channel adjustments to a succession of water pulses in gravel bed rivers
Authors: Ferrer‐Boix Carles , Hassan Marwan A.
Published: October 2015

Gravel bed rivers commonly exhibit a coarse surface armor resulting from a complex history of interactions between flow and sediment supply. The evolution of the surface texture under single storm events or under steady flow conditions has been studied by a number of researchers. However, the role of successive floods on the surface texture evolution is still poorly understood. An experimental campaign in an 18 m‐long 1 m‐wide flume has been designed to study these issues. Eight consecutive runs, each one consisting of a low‐flow period of variable duration followed by a sudden flood (water pulse) lasting 1.5 h, have been conducted. The total duration of the experiment was 46 h. The initial bed surface was created during a 280 h‐long experiment focused on the influence of episodic sediment supply on channel adjustments. Our experiments represent a realistic armored and structured beds found in mountain gravel bed rivers. The armor surface texture persists over the duration of the experiment. The experiment exhibits downstream fining of the bed‐surface texture. It was found that sorting processes were affected by the duration of low‐flow between flood pulses. Since bed load transport is influenced by sediment sorting, the evolution of bed load transport is impacted by the frequency of the water pulses: short interpulse durations reduce the time over which fine material (transported as bed load) can be winnowed. This, in turn, contributes to declining reduction of the bed load transport over time while the sediment storage increases.
Integrated crude selection and refinery optimization under uncertainty
Authors: Yang Yu , Barton Paul I.
Published: October 2015

Crude oil selection and procurement is the most important step in the refining process and impacts the profit margin of the refinery significantly. Due to uncertain quality of the crudes, conventional deterministic modeling and optimization methods are not suitable for refinery profitability enhancement. Therefore, a novel optimization scheme for crude oil procurement integrated with refinery operations in the face of uncertainties is presented. The decision process comprises two stages and is solved using a scenario‐based stochastic programming formulation. In Stage I, the optimal crude selections and purchase amounts are determined by maximizing the expected profit across all scenarios. In Stage II, the uncertainties are realized and optimal operations for the refinery are determined according to this realization. The resulting large‐scale mixed‐integer nonlinear programming formulation incorporates integer variables for crude selection and continuous variables for refinery operations, as well as bilinear terms for pooling processes. Nonconvex generalized Benders decomposition is used to solve this problem to obtain an
global optimum efficiently. © 2015 American Institute of Chemical Engineers AIChE J, 62: 1038–1053, 2016
Potential‐Assisted DNA Immobilization as a Prerequisite for Fast and Controlled Formation of DNA Monolayers
Authors: Jambrec Daliborka , Gebala Magdalena , La Mantia Fabio , Schuhmann Wolfgang
Published: October 2015

Highly reproducible and fast potential‐assisted immobilization of single‐stranded (ss)DNA on gold surfaces is achieved by applying a pulse‐type potential modulation. The desired DNA coverage can be obtained in a highly reproducible way within minutes. Understanding the underlying processes occurring during potential‐assisted ssDNA immobilization is crucial. We propose a model that considers the role of ions surrounding the DNA strands, the distance dependence of the applied potentials within the electrolyte solution, and most importantly the shift of the potential of zero charge during the immobilization due to the surface modification with DNA. The control of the surface coverage of ssDNA as well as the achieved speed and high reproducibility are seen as prerequisites for improved DNA‐based bioassays.