bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular phylogenetic and morphological studies on the systematic position of Heracula discivitta reveal a new subfamily of Pseudobistonidae (Lepidoptera: Geometroidea)
Authors: Wang Houshuai , Holloway Jeremy D. , Wahlberg Niklas , Wang Min , Nylin Sören 
Published: January 2019

AbstractHeracula discivitta Moore is an uncommon moth species currently recorded from India, Nepal and China. Although this species has traditionally been placed in Lymantriinae, its systematic position in Macroheterocera has been enigmatic due to its unique morphological features. Here we used molecular and morphological data to explore the systematic position of H. discivitta. Our molecular phylogenetic analyses indicate that this species is sister to Pseudobiston pinratanai Inoue, a member of a recently established monotypic family Pseudobistonidae. The examinations of morphological features further show that H. discivitta shares synapomorphies with Pseudobistonidae. Based on the analysis results, we propose a new subfamily of Pseudobistonidae (Heraculinae subfam.n.) to accommodate H. discivitta. The resemblance of the habitus to that of the brahmaeid genus Calliprogonos Mell & Hering is discussed.This published work has been registered on ZooBank,
http://zoobank.org/urn:lsid:urn:lsid:zoobank.org:pub:63D17850‐6D51‐4E03‐A5D6‐F9EF6E7AF402.
High‐throughput 3D modelling to dissect the genetic control of leaf elongation in barley (Hordeum vulgare)
Authors: Ward Ben , Brien Chris , Oakey Helena , Pearson Allison , Negrão Sónia , Schilling Rhiannon K. , Taylor Julian , Jarvis David , Timmins Andy , Roy Stuart J. , Tester Mark , Berger Bettina , van den Hengel Anton 
Published: January 2019

SummaryTo optimize shoot growth and structure of cereals, we need to understand the genetic components controlling initiation and elongation. While measuring total shoot growth at high throughput using 2D imaging has progressed, recovering the 3D shoot structure of small grain cereals at a large scale is still challenging. Here, we present a method for measuring defined individual leaves of cereals, such as wheat and barley, using few images. Plant shoot modelling over time was used to measure the initiation and elongation of leaves in a bi‐parental barley mapping population under low and high soil salinity. We detected quantitative trait loci (QTL) related to shoot growthper se, using both simple 2D total shoot measurements and our approach of measuring individual leaves. In addition, we detectedQTLspecific to leaf elongation and not to total shoot size. Of particular importance was the detection of aQTLon chromosome 3H specific to the early responses of leaf elongation to salt stress, a locus that could not be detected without the computer vision tools developed in this study.
Building a Global, Pediatric Vascular Access Registry: A Scoping Review of Trial Outcomes and Quality Indicators to Inform Evidence‐Based Practice
Authors: Schults Jessica A. , Rickard Claire M. , Kleidon Tricia , Hughes Rebecca , Macfarlane Fiona , Hung Jacky , Ullman Amanda J. 
Published: January 2019

AbstractBackgroundInternationally, there is a lack of comparative vascular access (VA) data for pediatric clinicians and organizations to benchmark outcomes, evaluate quality initiatives, and improve practice. A VA registry is needed to address these knowledge and data capture gaps.ObjectivesTo determine the range and heterogeneity of VA outcome measures or quality indicators reported in randomized controlled trials (RCTs) and clinical registries, to inform development of a homogeneous, reliable, minimum dataset for a pediatric VA registry.MethodsScoping review framework. A systematic search for RCTs reporting VA outcomes in pediatrics and neonates was undertaken in the Cochrane library, EMBASE, CINAHL, PubMed, MEDLINE, and EBSCO using a medical subject headings and key words related to VA and pediatrics. We included RCTs of children (0–18 years) reporting any VA outcome. We identified clinical registries reporting VA data in children (0–18) through web‐based searches using key words related to VA and clinical or quality registries. Additional registries were identified through peer consultation. The frequency and scope of outcome measures and quality indicators were extracted from trials and registries and evaluated.ResultsFrom 93 RCTs included, 214 different VA measures were reported, reflecting 14 outcome domains. The most commonly reported outcome domains were insertion (44 RCTs; 47%), noninfectious complications (33 RCTs; 35%), and infectious complications (30 RCTs; 32%). Of the 22 registries identified, VA‐associated infection was the main quality indicator routinely collected (12 registries; 55%). Outcomes such as mechanical complications and patient‐reported outcomes were infrequently collected.Linking Evidence to ActionVascular access outcomes reported in pediatric and neonatal RCTs are highly heterogeneous. Internationally, clinical registries currently collect minimal VA data with the exception of infection outcomes. A core dataset of reliable, relevant measures to children and clinicians for VA device quality is needed. This will enable a VA registry that facilitates inter‐institutional and international benchmarking.
Numerical Investigation on LNG Injection in a SI-ICE
Authors: Pasini Gianluca , Frigo Stefano , Antonelli Marco , Berardi Maria 
Published: January 2019

Since the beginning of this century, Liquefied Natural Gas (LNG) has been attracting more and more attention as a cleaner energy alternative to other fossil fuels, mainly due to the possibility to transport it over longer distances than natural gas in pipelines and lower environmental impact than other liquid fuels. It is expected that this trend in the use of LNG will lead to steady increases in demand over the next few decades.
At present, in the automotive sector, natural gas is employed as fuel in spark-ignited (SI) engines in the gas phase (CNG) adopting port-fuel injection system (PFI) in the intake manifold, with the main result of reducing CO2 emissions by up to 20%, compared with gasoline operation. However, SI engines which are operated in this manner suffer loss of peak torque and power due to a reduction in volumetric efficiency. Direct-Injection (DI) inside the cylinder can overcome this drawback by injecting CNG after intake valve closure. Another strategy could be the injection of natural gas in the liquid phase, both in PFI or DI mode. The injected fuel evaporation cools down the intake air; increasing the charge density with a substantial improvement in the engine volumetric efficiency and delivered power. However, at present, injection systems dedicated to cryogenic injection of natural gas are still in the prototype state.
In the present study, the volumetric efficiency and performance of a turbocharged, LNG fuelled SI-ICE were numerically analysed both in the cases of DI and PFI modes and compared with the results of a conventional CNG system. Various fuel injection timings and injector position were analysed. The engine performance was evaluated by means of a one-dimensional model developed with the simulation program GT-Power, while the verification of the LNG-air mixture characteristics was carried out with the commercial code Aspen HYSIS.
The numerical activity has shown that gaseous DI, before inlet valves closing, gives the worst result since methane, once injected into the cylinder, expands hindering the entry of air. On the other side, liquid PFI represents the best configuration to maximize the volumetric efficiency and therefore the engine power. All the technological issues related to a cryogenic liquid methane injection system were not taken into consideration in this study.
Integration of Printed Sensors in Plain Engine Bearings
Authors: Gorges Roger , Bisgrove William , Curtis Ryan , Carter Jeff , George James W. , Ritchie Jonathan , Wirth Ingo , Zoellmer Volker , Rusch Tim 
Published: January 2019

The integration of sensors in engine components has been a long-standing wish of engine manufacturers and researchers. Conventional probes are particularly difficult to mount in moving engine parts and require time-intensive and costly preparation, while often still not reaching the site of interest close enough. The advances recently made in the field of printed electronics enable new possibilities for sensor integration that previously were not possible. Particularly, crankshaft engine bearings are an interesting component to apply those new sensors to.
An important enabling factor for the successful sensor integration has been the increasing market penetration of polymer overlays for crankshaft bearings. The driving force behind this development was the pressure from legislation to reduce CO2 emissions, which in turn brought about new technologies such as start-stop and mild hybrids. Engine components now have to operate in much more aggressive environments, which in many cases only polymer overlays withstand. The unique application process of those coatings together with their material properties, such as robustness and non-conductivity, now allow embedding of electronic components right at the running surface of the bearings.
This paper details the development of a printed sensor that has been integrated into the bearing polymer overlay coating. Various results from respective rig testing of the sensor feedback throughout different load and speed conditions during operation are reported.
Turbulent Reactive Flow Modeling in Engines: A Robust and Accurate Toolkit/Software for Simulating Engine Dynamics
Authors: Carrington David B. , Waters Jiajia 
Published: January 2019

The Los Alamos turbulent reactive flow researchers, our modelers and simulation code developers have succeeded in providing the engine research and development community an encompassing, robust, accurate and easy to use software for engine modeling or simulations. This software is now known as the FEARCE Toolkit.
In this paper we discuss the physics present in the engine by discussion the methods we’ve employed to solve the model equations within the toolkit. Provided are background on what has been developed recently at LANL for internal combustion engine modeling.
An Experimental Study on Fuel Economy Improvement of a Marine Diesel Engine Using a Sequential Turbocharging System
Authors: Wang Hechun , Li Xiannan , Wang Yinyan , Li Hailin 
Published: January 2019

Marine diesel engines usually operate on a highly boosted intake pressure. The reciprocating feature of diesel engines and the continuous flow operation characteristics of the turbocharger (TC) make the matching between the turbocharger and diesel engine very challenging. Sequential turbocharging (STC) technology is recognized as an effective approach in improving the fuel economy and exhaust emissions especially at low speed and high torque when a single stage turbocharger is not able to boost the intake air to the pressure needed. The application of STC technology also extends engine operation toward a wider range than that using a single-stage turbocharger.
This research experimentally investigated the potential of a STC system in improving the performance of a TBD234V12 model marine diesel engine originally designed to operate on a single-stage turbocharger. The STC system examined consisted of a small (S) turbocharger and a large (L) turbocharger which were installed in parallel. Such a system can operate on three boosting modes noted as 1TC-S, 1TC-L and 2TC. A rule-based control algorithm was developed to smoothly switch the STC operation mode using engine speed and load as references. The potential of the STC system in improving the performance of this engine was experimentally examined over a wide range of engine speed and load. When operated at the standard propeller propulsion cycle, the application of the STC system reduced the brake specific fuel consumption (BSFC) by 3.12% averagely. The average of the exhaust temperature before turbine was decreased by 50°C. The soot and oxides of nitrogen (NOx) emissions were reduced respectively. The examination of the engine performance over an entire engine speed and torque range demonstrated the super performance of the STC system in extending the engine operation toward the high torque at low speed (900 to 1200 RPM) while further improving the fuel economy as expected. The engine maximum torque at 900 rpm was increased from 1680Nm to 2361 Nm (40.5%). The average BSFC over entire working area was improved by 7.4%. The BSFC at low load and high torque was significantly decreased. The application of the STC system also decreased the average NOx emissions by 31.5% when examined on the propeller propulsion cycle.
Investigation of NO2 Formation Kinetics in Dual-Fuel Engines With Lean Premixed Methane-Air Charge
Authors: Arabian Ehsan , Sattelmayer Thomas 
Published: January 2019

A dual fuel engine concept with lean premixed methane-air charge ignited by a diesel pilot flame is highly promising for reducing NOx and soot emissions. One drawback of this combustion method, however, is the high nitric dioxide (NO2) emissions observed at certain operating points. NO2 is a toxic gas, which is identifiable by its yellow color.
In this paper the conditions leading to increased NO2 formation have been investigated using a batch reactor model in Cantera. In a first step, it has been found that the high emission levels of NO2 can be traced back to the mixing of small amounts of quenched CH4 with NO from the hot combustion zones followed by post-oxidation in the presence of O2, requiring that the temperatures are within a certain range.
In the second step, NO2 formation in the exhaust duct of a test engine has been modeled and compared to the experimental results. For that purpose a well-stirred reactor model has been used that calculates the steady-state of a uniform composition for a certain residence time. An appropriate reaction mechanism that considers the effect of NO/NO2 on methane oxidation at low temperature levels has been used.
The numerical results of NO to NO2 conversion in the duct at low temperature and pressure levels show good agreement with the experimental results for various temperatures and concentrations of unburned methane. The partial oxidation of CH4 can be predicted well. It can be shown that methane oxidation in the presence of NO/NO2 at low temperature levels is enhanced via the reaction steps CH3 + NO2 ⇌ CH3O + NO and CH3O2 + NO ⇌ CH3O + NO2. In addition the elementary reaction HO2 + NO ⇌ NO2 + OH is the important NO oxidizing step.
Numerical Analysis of a Six-Stroke Gasoline Compression Ignition (GCI) Engine Combustion With Continuously Variable Valve Duration (CVVD) Control
Authors: Rajput Oudumbar , Ra Youngchul , Ha Kyoung-Pyo , Son You-sang 
Published: January 2019

Engine performance and emissions of a six-stroke Gasoline Compression Ignition (GCI) engine with wide range of Continuously Variable Valve Duration (CVVD) control were numerically investigated at low engine load conditions. For the simulations, an in-house 3-D CFD code with high fidelity physical sub-models was used and the combustion and emissions kinetics were computed using a reduced kinetics mechanism for a 14-component gasoline surrogate fuel. Double injections were employed to effectively form the local fuel/air mixtures with optimal reactivity. Several valve timing and duration variations through the CVVD control were considered under both positive valve overlap (PVO) and negative valve overlap (NVO) conditions. Effects of intake-valve re-breathing between the first expansion and the second compression strokes were also investigated.
Close attention was paid to understand the effects of two additional strokes of the engine cycle on the thermal and chemical conditions of charge mixtures that alter ignition, combustion and energy recovery processes. Double injections were found to be necessary to effectively utilize the additional two strokes for the combustion of overly mixed lean charge mixtures during the second power stroke (PS2). It was found that combustion phasing in both power strokes is effectively controlled by the intake valve closure (IVC) timing since it affects the effective compression ratio. Engine operation under NVO condition with fixed exhaust valve opening (EVO) and IVC timings tends to advance the ignition timing of the first power stroke (PS1) but has minimal effect on the ignition timing of PS2. Re-breathing was found to be an effective way to control the ignition timing in PS2 at a slight expense of the combustion efficiency.
The operation of a six-stroke GCI engine could be successfully simulated and the operability range of the engine could be substantially extended by employing the CVVD technique. In addition, the control of valve timings could successfully control the thermodynamic and compositional conditions of in-cylinder mixtures that enable to control the combustion phasing.
Modular 9.0L and 4.5L Non-Road Spark-Ignited Engines for Power Generation
Authors: Gillette Allen , Dees Jesse , Crudden John , Petcoff Anthony 
Published: January 2019

Following the successful commercial use of a 9.0L, V-8 automotive-derivative engine for stationary power generation, a new 4.5L, four-cylinder engine has been developed utilizing a modular family design approach. Substantial commonality of power cylinder components has been achieved including the complete power cylinder and cylinder head. This paper describes the design and development approach to the engine family.
These spark-ignited engines are typically used for standby emergency power and demand response applications utilizing commercial grade natural gas or propane. Driving a synchronous electrical generator operating at 60 HZ or 50Hz, engine speeds are either 1800 rpm/3600 rpm or 1500 rpm/3000 rpm respectively, depending upon selection of either a 2-pole or 4-pole alternating current generator. Designed for stoichiometric combustion, the engine configurations can include naturally-aspirated, turbocharged or turbocharged and after-cooled versions. Depending upon end-use applications, exhaust emissions technology and regulatory compliance can be met solely through engine calibration or inclusion of a 3-way catalyst with active air-fuel ratio control.
Since the 9.0L engine version was successfully introduced in 2012, significant efforts have been undertaken to achieve commonality of desired features between the existing veeengine and the future in-line versions, including optimization of performance characteristics in consideration of future power rating structures. Starting from 9.0L commercial introduction, the content herein specifically describes the development of the new 4.5L engine with regard to design and analysis.
Application of Variable Valve Actuation Strategies and Direct Gasoline Injection Schemes to Reduce Combustion Harshness and Emissions of Boosted HCCI Engine
Authors: Hunicz Jacek , Mikulski Maciej 
Published: January 2019

One of the pending issues regarding Homogeneous Charge Compression Ignition (HCCI) engines is high load operation limit constrained by excessive pressure rise rates (PRRs). The present study investigates various measures to reduce combustion harness in a residual-affected HCCI engine. At the same time, the impact of those measures on efficiency and emissions is assessed. Experimental research was performed on a single cylinder engine equipped with a fully-flexible valvetrain mechanism and direct gasoline injection. The HCCI combustion mode with exhaust gas trapping was realized using negative valve overlap and fuel reforming, achieved via the injection of a portion of fuel during exhaust re-compression.
Three measures are investigated for the PRR control under the same reference operating conditions, namely: (i) variable intake and exhaust valve timing, (ii) boost pressure adjustment and (iii) split fuel injection to control the amount of fuel injected for reforming. Variable exhaust valve timing enabled control of the amount of trapped residuals, and thus of the compression temperature. The reduction in the amount of trapped residuals, at elevated engine load, delays auto-ignition, which results in a simultaneous reduction of pressure rise rates and nitrogen oxides emissions. The effects of intake valve timing are much more complex, because they include the variability in the amount of intake air, the thermodynamic compression ratio as well as the in-cylinder fluid flow. It was found, however, that both early and late intake valve openings delay auto-ignition and prolong combustion. Additionally, the reduction of the amount of fuel injected during exhaust re-compression further delays combustion and reduces combustion rates. Intake pressure reduction has by far the largest effect on peak pressure reduction yet is connected with excessive NOx emissions. The research successfully identifies air-path and injection techniques, which allow for the control of combustion rates and emissions under elevated load regime, thus shorting the gap towards the real-world application of HCCI concepts.
Experimental Investigation of Soot Accumulation and Regeneration in a Catalyzed Gasoline Particulate Filter Utilizing Particulate Quantification and Gas Speciation Measurements
Authors: Rathod Dhruvang , Onori Simona , Filipi Zoran , Hoffman Mark 
Published: January 2019

Recent particulate regulations for gasoline passenger cars have prompted the utilization of Gasoline Particulate Filters (GPF’s) to mitigate particulate emissions. This study overviews a comprehensive experimental methodology for examination of essential GPF parameters: spatial exothermic temperature rise, particulate trapping efficiency, and the pressure rise versus particulate loading. A GDI vehicle equipped with a subfloor catalytically washcoated GPF downstream of the three-way catalyst was operated on a chassis dynamometer for data collection. Accelerated soot accumulation procedures were developed to expedite the testing while avoiding passive particulate regeneration based on both particulate concentration and size distributions. Soot concentrations pre and post GPF were used to measure the soot trapping efficiency and total soot accumulation. Fuel-cut coast events, common in real-world driving, were utilized to initiate worst case GPF regenerations, namely regenerations which produce maximum temperature rise due to the limited exhaust flow through the GPF. CO2 measurements simultaneously measured before and after the GPF were examined to calculate the quantity of soot burned during each regeneration event. Thermocouples located inside the GPF were implemented to obtain the spatially disparate, transient temperature traces and analyzed to obtain insights on the soot distribution inside the GPF. The maximum exothermic temperature rise within the GPF was tracked for different soot loadings and regeneration temperatures to ensure GPF substrate and catalytic washcoat health. Most initial soot loadings required multiple ‘fuel-cut coast’ regenerations for complete soot oxidation of all trapped particulate mass.
Additionally, externally supplied oxygen was utilized to obtain complete GPF regeneration in a single event. This purpose built system created O2 availability while maintaining constant GPF temperatures, similar to actively commanding lean A/F ratios during vehicle operation. Emissions measurements indicated that this system successfully regenerated all GPF soot. However, due to magnitude disparity between exhaust flow and total exothermic heat released, the thermocouples inside the GPF recorded only minimal exothermic temperature rises, providing confidence that lean active regeneration strategies pose little threat to GPF health.