bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rule-Based Alternator Control Using Predicted Velocity for Energy Management Strategy
Authors: Shin Jaewook , Kim Haksu , Baek Seungeon , Sunwoo Myoungho , Han Manbae 
Published: September 2019

AbstractThe market concern of improvement of vehicle safety and its convenience to drive a vehicle has resulted in the growth of the demand for vehicular electronic equipment. This trend requires additional power in the vehicle and thus makes prone to the increase of fuel consumption for vehicles equipped with internal combustion engines. To minimize this fuel consumption, an efficient energy management (EM) strategy for the electrical system of alternator and battery is required. This paper proposes a successful EM strategy based on the rule-based alternator control using predictive information. The proposed strategy reduces fuel consumption by charging batteries using the residual kinetic energy during deceleration. In particular, we predict electrical energy that is recovered by the residual energy using a Markov chain-based velocity prediction algorithm. The accommodation of predicted electrical energy and current vehicle information determines one of the three predefined control modes, such as charge, hold, and discharge, depending on vehicle driving states. This control mode determines the power generation from the alternator and controls the amount of torque to the vehicle electrical system. The proposed strategy is verified through simulation and experiment. The simulation with the new EM strategy is validated as comparing the operation difference with a conventional proportional-integral (PI) control algorithm under the same driver behaviors. Further validation in real vehicle driving experiment shows that fuel consumption was reduced by 2.1% compared to the conventional PI control algorithm.
Low-Dielectric Constant Nanoporous Epoxy for Electronic Packaging
Authors: Jiang Jisu , Keller Landon , Kohl Paul A. 
Published: September 2019

AbstractEpoxide functionalized poly(propylene carbonate) (ePPC) was included in an epoxy resin formulation and thermally decomposed to create nanoporous epoxy film. The dielectric constant of the porous epoxy was lower than the epoxy formulation control. The introduction of 30% porosity in the epoxy lowered the dielectric constant from 3.78 to 2.76. A postporosity chemical treatment further lowered the dielectric constant. Hexamethyldisilazane (HMDS) was used to terminate the pore walls with the hydrophobic silane layer and reduce both the dielectric constant and tangent loss of the porous epoxy. Two different styrene maleic anhydride crosslinking agents were used in the epoxy formulation, styrene maleic anhydride 2000 (SMA2000) and styrene maleic anhydride 4000 (SMA4000). The effect of the maleic anhydride concentration within SMA on the electrical, mechanical, and thermal properties of porous epoxy film was evaluated. Epoxy films crosslinked with SMA2000 resulted in films with a higher dielectric constant compared to films prepared with SMA4000 due to higher mole fraction of maleic anhydride within SMA2000. However, SMA2000 crosslinked films yielded films with better mechanical and thermal properties. SMA2000 crosslinked films with 30% porosity had a coefficient of thermal expansion (CTE) of 35.2 ppm/K and glass transition temperature of 143 °C.
Longitudinal–Flexural–Torsional Dynamic Behavior of Liquid-Filled Pipelines: An Analytic Solution
Authors: Pavlou Dimitrios G. 
Published: September 2019

Abstract
The 14 partial differential equation system describing the longitudinal–flexural–torsional dynamic behavior of liquid-filled pipelines contains coupled equations due to mutual boundary conditions and Poisson contraction ratio terms. Solutions of the above system are available in the frequency-domain or in the time-domain (method of characteristics (MOC)). In this paper, an analytic solution in the domain of time and space is achieved. Double integral transform, namely, finite sine Fourier transform (FSFT) and Laplace transform, is applied to the derived system of the 14 fourth-order partial differential equations, yielding an algebraic system in terms of the transformed variables. The inversion of the FSFT is an easy task, but the analytic inversion of the Laplace transforms is very challenging. Both integral transform inversions of the 14 transformed variables are successfully performed, and an analytic matrix formula in the domain of time and space along with numerical results is obtained.
On the Hydraulics of Downward Sloping Pipes With Entrapped Air Pockets
Authors: Warda H. A. , Wahba E. M. , Ahmed E. N. 
Published: September 2019

Abstract
In this study, air–water flow in a downward sloping pipe subsequent to the entrapping of an air pocket is investigated both numerically and experimentally. A transient, two-dimensional computational fluid dynamics model is applied to study the different possible flow regimes and their associated phenomena. The numerical model is based on the Reynolds-averaged Navier–Stokes (RANS) equations and the volume of fluid (VOF) method. Both numerical and experimental investigations provide visualization for the hydraulic jump, the blowback regime, and the full gas transport regime. The numerical results predict that the flow structure in the pipe downstream the toe of the hydraulic jump is subdivided into three distinct regions including the jet layer, the shear zone, and the circulation region, which agrees qualitatively with the previous investigations of the hydraulic jump characteristics in open channel flow. Numerical results are in reasonable agreement with the experimental measurements of the circulation length and the hydraulic jump head loss.
A Numerical and Experimental Study on the Fabrication GaN Films by Chemical Vapor Deposition
Authors: Wong Sun , Jaluria Yogesh 
Published: September 2019

Abstract
Computational modeling and simulation are employed to study a rotating susceptor vertical impinging chemical vapor deposition (CVD) reactor to predict GaN film deposition. Many metal-organic chemical vapor deposition reactor manufacturers use prior experience to design and fabricate CVD reactors without a fundamental basis for the process and information on the optimal conditions for the deposition. Through trial and error, they fine tune the gas flow parameters, heater temperatures, chamber pressure, and concentration of species gases for optimal growth. However, expensive raw precursor gas and time are wasted through this method. A computational model is an important step in the CVD reactor design and GaN growth prediction. It can be used to model and optimize the reactor to yield favorable operating conditions. In this paper, a simple geometry consisting of a rotating susceptor and flow guide is considered. The focus is on gallium nitride (GaN) thin films. The study shows how the computational model can benefit reactor design. It also presents comparisons between model prediction results and experimental data from a physical, practical, system. Commercially available software is used, with appropriate modifications, and the results obtained are discussed in detail.
A Simulative and Experimental Approach Toward Eddy Current Nondestructive Evaluation of Manufacturing Flaws and Operational Damage in CFRP Composites
Authors: James Robin , Faisal Haider Mohammad , Giurgiutiu Victor , Lilienthal David 
Published: September 2019

Abstract
The manufacturing process of carbon fiber reinforced polymer (CFRP) composite structures can introduce many characteristic defects and flaws such as fiber misorientation, fiber waviness, and wrinkling. Therefore, it becomes increasingly important to detect the presence of these defects at the earliest stages of development. Eddy current testing (ECT) is a nondestructive inspection (NDI) technique that has been proven quite effective in detection of damage in metallic structures. However, NDI of composite structures has mainly relied on other methods such as ultrasonic testing (UT) and X-ray to name a few and not much on ECT. In this paper, the authors explore the possibility of using ECT in NDI of CFRP composites by conducting simulations and experiments thereafter. This research is based on the fact that the CFRP displays some low-level electrical conductivity due to the inherent conductivity of the carbon fibers. This low-level conductivity may permit eddy current pathways to cause the flow of eddy currents in the CFRP composites that can be exploited for nondestructive damage detection. An invention disclosure describing our high-frequency ECT method has also been processed. First, the multiphysics finite element method (FEM) simulation was used to simulate the detection of various types of manufacturing flaws and operational damage in CFRP composites such as fiber misorientation, waviness, wrinkling, and so on. Thereafter, ECT experiments were conducted on CFRP specimens with various manufacturing flaws using the Eddyfi Reddy eddy current array (ECA) system.
A Two-Dimensional Experimental and Numerical Study of Moonpools With Recess
Authors: Ravinthrakumar Senthuran , Kristiansen Trygve , Ommani Babak 
Published: September 2019

Abstract
Moonpool resonance is investigated in a two-dimensional setting in terms of regular, forced heave motions of a model with moonpool with different rectangular-shaped recess configurations. A recess is a reduced draft zone in the moonpool. Dedicated experiments were carried out. The model consisted of two boxes of 40 cm width each, with a distance of 20 cm between them. Recess configurations varying between 5 cm and 10 cm in length and 5 cm in height were tested. Different drafts were also tested. A large number of forcing periods and five forcing amplitudes were tested. A time-domain boundary element method (BEM) code based on the linear potential flow theory was implemented to investigate the resonance periods, mode shapes, as well as the moonpool response as predicted by the (linear) potential flow theory. Dominant physical effects were discussed, in particular damping due to flow separation from the sharp corners of the moonpool inlet and recess. The effect of the recess on the piston-mode behavior is discussed. The nondimensional moonpool response suggests strong viscous damping at the piston-mode resonance. The viscous BEM (VBEM) simulations demonstrate improvement over inviscid BEM, although further improvement of the method is needed. The VBEM simulations are, in general, in good agreement with the experiments. For the largest recess case, some discrepancies are observed in the amplitude-dependent response amplitude operators (RAOs). The piston-mode shapes are clearly different from the near flat free-surface elevation for a moonpool without recess, consistent with the recently published theory.
Improving the Tribological Properties of Al-7Fe-5Ni Alloys via Friction Stir Processing
Authors: Fekri Soustani M. , Taghiabadi R. , Jafarzadegan M. , Shahriyari F. , Rahmani A. 
Published: September 2019

AbstractDue to the limited solid-solubility of Fe and Ni in Al, coarse brittle intermetallics rich in Fe and/or Ni are inevitably formed in the as-cast microstructure of Al-Fe-Ni alloys. Upon formation, Fe(Ni)-rich intermetallics significantly deteriorate the properties and restrict the application of alloy in as-cast condition. The purpose of this study was to investigate the effect of friction stir processing (FSP) on microstructure and tribological properties of cast Al-7Fe-5Ni alloy. The dry sliding wear tests were done by using a pin-on-disk type machine under the applied pressures of 1, 2, and 3 MPa, sliding distance of 1000 m, at room temperature. According to the results, FSP (1250 rpm and 8 mm/min) effectively refined the microstructure, especially the coarse primary Al9FeNi intermetallics and eliminated the alloy casting-related defects. FSP also converted the large columnar grains of the cast alloys to the ultrafine equiaxed grains. These microstructural changes enhanced the substrate mechanical properties thereby increased its resistance against sliding-induced plastic flow, leading to the higher tribolayer stability on the surface, and accordingly, higher wear resistance. The results showed that applying 1-pass FSP reduced the wear by 13% and 53% under applied pressures of 1 and 3 MPa, respectively. The friction results also revealed that, compared with the as-cast sample, FSPed samples exhibited lower friction coefficient and friction coefficient fluctuations.
The Benefit of Using Multiple Thin Tanks Versus a Short Big Tank for Thermal Storage in Ceramic-Sphere Packed Bed With Airflow
Authors: Wang Yan , Li Peiwen , Wang Zhifeng , Yang Bei , Yuan Guofeng 
Published: September 2019

Abstract
To make a better thermal storage system that uses air as the heat transfer fluid flowing through a packed-bed of ceramic spheres (Al2O3) as thermal storage materials, the present work studied cases using multiple small-diameter thin tanks to replace a large-diameter big tank while keeping the same total volume and the same air flow rate. Performance analysis of thermal storage has been conducted for comparison and optimization. The long flow passage and faster flow velocity of air in the small-diameter tanks was found to significantly benefit thermal storage performance compared with that of a short big tank. It resulted in a longer duration of discharge of high-temperature airflow, if the same operation time is applied to the two situations. The faster airflow enhances the heat transfer between air and thermal storage material, although it incurs larger pressure loss. Overall, the energy storage efficiency of using several thin tanks can be significantly better than that of using a big short tank if the height-to-diameter ratio in the multiple thin tanks is properly optimized. The optimization methodology and results are of great significance to the development of thermal storage systems that use air as heat transfer fluid and rocks or ceramic spheres as the packed-bed material for thermal storage.
Molecular basis and biological function of variability in spatial genome organization
Authors: Finn Elizabeth H. , Misteli Tom 
Published: September 2019

Heterogeneity in genome organization
How the genome is organized in the three-dimensional space of the cell nucleus influences the activity of gene expression. Finn and Misteli review features of genome architecture and cell- and allele-specific variability in spatial genome organization. They also connect stochasticity in gene transcription and variability in genome organization and discuss the functional consequences of genome variability at the cell and population levels in development and disease.

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Revolutions in agriculture chart a course for targeted breeding of old and new crops
Authors: Eshed Yuval , Lippman Zachary B. 
Published: September 2019

Growing more and better food
Increasing human populations demand more productive agriculture, which in turn relies on crop plants adjusted for high-yield systems. Eshed and Lippman review how genetic tuning of the signaling systems that regulate flowering and plant architecture can be applied to crops. Crops that flower sooner might be adaptable to regions with shorter growing seasons, and compact plant shapes might facilitate agricultural management. The universality of these plant hormone systems facilitates application to a range of crops, from the orphan crop teff to the well-known wheat.

Science
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Canopy structure in Late Cretaceous and Paleocene forests as reconstructed from carbon isotope analyses of fossil leaves
Authors: Graham Heather V. , Herrera Fabiany , Jaramillo Carlos , Wing Scott L. , Freeman Katherine H. 
Published: September 2019

Abstract
While modern forests have their origin in the diversification and expansion of angiosperms in the Late Cretaceous and early Cenozoic, it is unclear whether the rise of closed-canopy tropical rainforests preceded or followed the end-Cretaceous extinction. The “canopy effect” is a strong vertical gradient in the carbon isotope (δ13C) composition of leaves in modern closed-canopy forests that could serve as a proxy signature for canopy structure in ancient forests. To test this, we report measurements of the carbon isotope composition of nearly 200 fossil angiosperm leaves from two localities in the Paleocene Cerrejón Formation and one locality in the Maastrichtian Guaduas Formation of Colombia. Leaves from one Cerrejón fossil assemblage deposited in a small fluvial channel exhibited a 6.3‰ range in δ13C, consistent with a closed-canopy forest. Carbon isotope values from lacustrine sediments in the Cerrejón Formation had a range of 3.3‰, consistent with vegetation along a lake edge. An even-narrower range of δ13C values (2.7‰) was observed for a leaf assemblage recovered from the Cretaceous Guaduas Formation, and suggests vegetation with an open canopy structure. Carbon isotope fractionation by Late Cretaceous and early Paleogene leaves was in all cases similar to that by modern relatives, consistent with estimates of low atmospheric CO2 during this time period. This study confirms other lines of evidence suggesting that closed-canopy forests in tropical South America existed by the late Paleocene, and fails to find isotopic evidence for a closed-canopy forest in the Cretaceous.
Selective laser trabeculoplasty versus topical medication as initial glaucoma treatment: the glaucoma initial treatment study randomised clinical trial
Authors: Ang Ghee Soon , Fenwick Eva K , Constantinou Marios , Gan Alfred Tau Liang , Man Ryan Eyn Kidd , Casson Robert J , Finkelstein Eric A , Goldberg Ivan , Healey Paul R , Pesudovs Konrad , Sanmugasundram Sutha , Xie Jing , McIntosh Rachel , Jackson Jonathan , Wells Anthony P , White Andrew , Martin Keith , Walland Mark J , Crowston Jonathan G , Lamoureux Ecosse Luc 
Published: September 2019

Background/AimsTo determine if selective laser trabeculoplasty (SLT) is superior to topical medication as a first-line treatment for glaucoma on quality of life (QoL) and clinical outcomes.MethodsIn this international, longitudinal, multisite randomised controlled trial, treatment naïve mild-to-moderate primary open angle or exfoliation glaucoma patients were randomised 1:1 to SLT or topical medication. Glaucoma-specific QoL (primary outcome) was measured using the Glaucoma Outcomes Assessment Tool (GOAT; 342 items, 12 domains). Secondary outcomes included rate of successful intraocular pressure (IOP) reduction (>25% reduction from baseline) and presence of ocular surface disease including conjunctival hyperaemia and eyelid erythema. Our intention-to-treat analysis was performed at months 12 and 24.ResultsOf 167 enrolled patients, 83 and 84 were randomised to SLT and topical medication, respectively; and 145 (n=75 SLT, n=70 medication) completed 24-month follow-up. While both treatment arms achieved significant within-group gains in GOAT outcomes at both endpoints, SLT patients reported a greater between-group improvement in ‘social well-being’ compared with medication patients (mean±SE=0.28±0.13; p=0.034) at 24 months. At month 24, the rate of successful IOP reduction was 18.6% (95% CI 3.0% to 34.3%, p=0.022) higher (absolute difference) in the medication compared with SLT group. More individuals in the medication group had conjunctival hyperaemia and eyelid erythema compared with SLT at 24 months.ConclusionOverall, we did not find evidence that SLT was superior to medication in improving glaucoma-specific QoL. While we found superior IOP reduction in the medication arm, eyelid erythema and conjunctival hyperaemia were more prevalent in these patients compared with the SLT group.Trial registrationACTRN12611000720910.
Strength training as a supplemental therapy for androgen deficiency of the aging male (ADAM): study protocol for a three-arm clinical trial
Authors: Kralik Michal , Cvecka Jan , Buzgo Gabriel , Putala Matus , Ukropcova Barbara , Ukropec Jozef , Killinger Zdenko , Payer Juraj , Kollarik Boris , Bujdak Peter , Raastad Truls , Sedliak Milan 
Published: September 2019

IntroductionAndrogen deficiency of the ageing male is a clinical syndrome resulting from the low production of androgens (testosterone levels <6.9 nmol/L) with symptoms including decline in lean mass, muscle strength, increases in body mass and overall fat mass. The aim of the study is to examine the effect of a 12 week strength training intervention on body composition, physical function, muscle cellular and molecular and selected biochemical markers of metabolic health in hypogonadal patients.Methods and analysisThe study is three-group controlled 12-week experiment to assess the effect of strength training on hypogonadal patients with testosterone replacement therapy and newly diagnosed males without testosterone replacement therapy. Age matched healthy eugonadal males are also engaged in strength training. Lean mass is used to determine sample size indicating, that 22 subjects per group will be sufficient to detect intervention related changes at the power of 0.90. All outcomes are collected before the intervention (pre-intervention assessments) and after the intervention (post-intervention assessments). Clinical outcomes are body composition (lean mass, fat mass and total body mass) measured by dual-energy X-ray absorptiometry, physical functioning assessed by physical tests and psychosocial functioning. The most important haematological and biochemical parameters included are glucose, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, testosterone, luteinizing hormone, follicle-stimulating hormone, sexhormone-binding globulin, insulin and prostate-specific antigen. Muscle cellular and molecular outcomes are muscle fibre size and regulators of muscle fibre size. Muscle cellular outcomes are measured from muscle biopsies obtained from musculus vastus lateralis.Ethics and disseminationThis trial is approved by Ethics Committee of the University Hospital in Bratislava, Slovakia, (ref. trial number: 127/2017) and all subjects will be fully informed on the rationale, risks and benefits of the study and sign the written informed consent prior to entering the study. Results will be published in peer-reviewed journals and presented in scientific conferences.Trial registration numberNCT03282682