bluuebunny/crossref_metadata_2025_split huggingface dataset:
Computer Aided Methodology for the Optimization of an Electric Motorcycle Suspension
Authors: Pabón Villamizar Dany , Roa Prada Sebastián 
Published: January 2020

Abstract
There are almost 9 million motorcycles registered only in the United States, while in other much smaller countries such as Colombia, this number can exceed 8 million. However, the population of Colombia is about six times smaller than the population in the United States. This demonstrates that for many people around the world, motorcycles are a great transportation method, which at the same time can provide a solution to the problems of urban traffic and scarcity of parking space. In addition to the problems associated with traffic, there are also public health problems related to the air pollution generated by internal combustion engines in motor vehicles. The issue of greenhouse gases emission from motor vehicles is being tackled by electric propulsion systems. The massive use of electric vehicles can have a strong positive impact in the quality of life of people and the environment. Therefore, electric motorcycles can become an optimal solution for transportation, by reducing the problems of urban traffic and space, while also being friendly with the environment. Two ways to help popularizing these vehicles are by reducing their cost and improving their performance. This work focuses on the optimization of the suspension system which is one of the key components of a motorcycle. The main function of the suspension system is to provide safety and comfort to the riders, two conditions that must be guaranteed in a good design. This article proposes a methodology for the optimal design of a motorcycle suspension, considering the different phases of development, starting with the geometric design, where the different parameters are determined for the front suspension, such as Rake Angle and Trail, and for the rear suspension, such as the inclination and the geometry of the swing arm system. Next, the detailed design is carried out, making sure that the elements of the suspension coincide with the dimensions at the attachment points to the chassis. Once all the geometry is available, the kinematic analysis is carried out, to assess the behavior of the system during the wheel trip. A structural analysis is performed to evaluate stresses, stiffness and resonance frequencies of the system, and to evaluate the minimum safety factor of the structure under the action of typical loads. With the final geometry of the system, a lumped parameter model can be obtained to rapidly observe its transient behavior under the effect of different irregularities that may be encountered on the road, which lead to the optimization of the parameters that offer greatest comfort to the rider. This set of parameters was used as inputs for the representation of the system in the physical modeling simulation interface Simmechanics® to generate final performance graphs. The results obtained with this methodology covered the different aspects that must be considered in the design of an important part of a transportation system such as an electric motorcycle.
Computational Simulation and Analysis of Major Control Parameters of Time-Dependent PV/T Collectors
Authors: Shi Jimeng , Lin Cheng-Xian 
Published: January 2020

Abstract
In order to improve performance of photovoltaic/thermal (or PV/T for simplicity) collectors, this paper firstly validated a previous computational thermal model and then introduced an improved computational thermal model to investigate the effects of the major control parameters on the thermal performance of PV/T collectors, including solar cell temperature, back surface temperature, and outlet water temperature. Besides, a computational electrical model of PV/T system was also introduced to elaborate the relationship of voltage, current and power of a PV module (MSX60 poly-crystalline solar cell) used in an experiment in the literature. Simulation results agree with the experimental data very well. The effects of the time-steps from 1 hour to minute, which is closed to the real time, were also reported. At last, several suggestions to improve the efficiency of PV/T system were illustrated.
Analysis of Flow Through Packed Bed of Spheres Containing Phase Change Materials for Thermal Energy Storage Applications
Authors: Prabhu Vinit V. , Languri Ethan , Nawaz Kashif 
Published: January 2020

Abstract
The research on thermal energy storage (TES) systems have received a lot of attention in recent decades for sustainable use of thermal energy in various industrial and residential applications. The existing challenge in designing the TES is the response time of charging and discharging cycles that keeps these systems away from wide utilization in industries. Literature data show that beside the low thermal conductivity of most phase change materials (PCMs) as active media in TES systems, the poor flow distribution may be another factor affecting the response rate. This study aims to considerably reduce the response time by packing the PCMs in a bed of spheres made of high thermal conductivity material. The response rate during the charging cycle is studied numerically by passing hot water at 70 °C over the packed bed of spheres. The numerical analysis is performed using ANSYS Fluent 19. The PCM used in this study is a paraffin and has a melting point of 48 °C. The response rate of the system is studied and it is compared to other similar systems mentioned in literature. The amount of energy storage is also studied by changing the flow rate of water.
Investigation of Cyclic and Frequency Nanoindentation Effects in Polydimethylsiloxane
Authors: Patel Hinal , Yang Chen , Lee Howon , Pelegri Assimina A. 
Published: January 2020

Abstract
The nanoindentation response of polydimethylsiloxane (PDMS) is examined using single nanoindentation loading and small-scale fatigue. It is well known that viscoelastic material response is inherently related to the local loading and environmental conditions. First, quasistatic nanoindentation experiments were performed at various depths through the specimen to benchmark our nanoindentation results with literature data. The PDMS cyclic and frequency dependence to quasi-static and dynamic nanoindentation loading was studied and a ‘load/partial-unload’ technique was employed to investigate nanoindentation modulus variation through the thickness of the specimen. The frequencies of the small-scale fatigue tests were varied to study periodic response. The average indentation modulus for PDMS at 2mN load-controlled tests was 4.37 ± 0.1 MPa. The PDMS sample had an average indentation modulus value of 3.94 ± 0.06 MPa for 3mN load-controlled tests. The indentation moduli decreased as the maximum depth increased because the stiffness reduced when indentations were performed further from the surface. The single nanoindentation data was confirmed with literature values and validated the precision of nanoindentation testing.
Small-scale fatigue tests were implemented at 50 cycles with frequencies of 1, 0.5, and 0.033 Hz. The lower frequencies displayed an increase in maximum depth at a given controlled load due to relaxation and creep effects. As with the single nanoindentations, the small-scale fatigue tests confirmed the decreasing trend of indentation moduli as the maximum depth increased. Overall, the two nanoindentation methods corroborated similar trends in changes of the PDMS mechanical response.
Additive Manufacturing of Kevlar Reinforced Epoxy Composites
Authors: Nawafleh Nashat , Chabot Jordan , Aljaghtham Mutabe , Oztan Cagri , Dauer Edward , Gorguluarslan Recep M. , Demir Teyfik , Celik Emrah 
Published: January 2020

Abstract
Additive manufacturing is defined as layer-by-layer deposition of materials on a surface to fabricate 3D objects with reduction in waste, unlike subtractive manufacturing processes. Short, flexible Kevlar fibers have been used in numerous studies to alter mechanical performance of structural components but never investigated within printed thermoset composites. This study investigates the effects of adding short Kevlar fibers on mechanical performance of epoxy thermoset composites and demonstrates that the addition of Kevlar by 5% in weight significantly improves flexure strength, flexural modulus, and failure strain by approximately 49%, 19%, and 38%, respectively. Hierarchical microstructures were imaged using scanning electron microscopy to observe the artefacts such as porosity, infill and material interdiffusion, which are inherent drawbacks of the 3D printing process.
Nonlinear Dynamic Analysis of an Asymmetric Ball Bearing Rotor System
Authors: Bahan Doğancan , Ciğeroğlu Ender 
Published: January 2020

Abstract
Performance of ball bearing–rotor systems are highly dependent on and often limited by characteristics of ball bearings. Several studies are available in the literature, investigating varying compliance and subharmonic resonances of ball bearings. Most of the studies are carried out with rigid rotors to focus on modelling of the bearings. There exist few studies which take flexibility of rotors into account. Furthermore, even if the rotor flexibility is modelled, most of the time symmetrical rotors are considered. However, rotors are rarely symmetric in realistic applications due to different locations of bearings and different weights of rotor components (compressors, turbines etc.). In this study, an asymmetric, balanced, flexible rotor supported by ball bearings considering Hertzian contact and radial clearance is investigated. Rotor shaft is modelled with Nelson finite rotor elements using Timoshenko beam theory and disks are considered as rigid masses. Harmonic Balance Method (HBM) is used to obtain nonlinear algebraic equations in the frequency domain and Alternating Frequency Time (AFT) method is utilized to find Fourier coefficients of nonlinear bearing forces. In order to decrease the number of nonlinear equations to be solved, Receptance Method (RM) is applied. Resulting set of nonlinear algebraic equations is solved by using Newton’s method with arclength continuation. Several case studies are performed and effects of asymmetry on nonlinear periodic vibration response of rotors are studied.
Study of Metallurgical and Mechanical Behavior of Laser Butt-Welded Dissimilar Joint of Inconel and Stainless Steel
Authors: Jaypuria Sanjib , Gupta Santosh Kumar , Suresh-Fazeela Sulthan , Pratihar Dilip Kumar , Chakrabarti Debalay , Jha M. N. 
Published: January 2020

Abstract
High energy density welding processes like laser and electron beam welding are capable of welding dissimilar plates with much ease due to high power density and low heat input in spite of the varying thermos-physical properties of the used alloys. The present work is aimed to check the feasibility of joint prepared with laser welding of SS 316L and Inconel 718 plates. The experiments are designed to study the effect of welding speed on the mechanical and metallurgical behavior of the joints without any offset to joint line. The formation of laves phases is confirmed by energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) phase analysis. These laves phase are micro-segregation of Nb, Fe, C and Cr, which is because of high temperature in a small area of fusion zone (FZ) due to intense heat of laser source. Micro-segregation of different elements has led to micro-fissures, which is detrimental for the joints operating at elevated temperature. Cooling rate and peak temperature during welding play the significant role in obtaining a sound quality joint. The present work gives an insight on feasibility of laser welded joint of SS 316L and Inconel 718 with suitable selection of welding speed during laser welding.
Thermoelectric Generator-Based System for Energizing Low-Power Communication and Geolocation Electronics
Authors: Eldaly Mamdouh , Pokharel Ashish , Petralia Michael , Unnthorsson Runar , Dell Robert 
Published: January 2020

Abstract
A small-scale thermoelectric generator (TEG) system produces a power of 1.43 W at a temperature differential between the thermoelectric module (TEM) surfaces of 70.00°C. This can cold-start a GSM locator and broadcast coordinates using an SMS message. Ultra-low power off-the-shelf electronics are combined to produce a reliable cellular signal and generate the coordinates, eliminating the need for dedicated GPS modules and reducing the total power consumption. A supercapacitor-based charging system was designed to store charge from the TEMs and discharge a constant 5.2 V to power the electronics. The system requires approximately 60 seconds from a cold start to send geographic coordinates. Designs for several cold blocks, used to generate the temperature differential for the TEMs, were investigated, including designs utilizing phase-change material (PCM) and water.
Design, Analysis and Test of Multi-Stage Crashworthiness Energy Absorbing Device for Railway Vehicles
Authors: Hong Haifeng , Liu Hongtao , Fang Ziwen , Wang Kefei , Wang Jianran , Luo Qi 
Published: January 2020

Abstract
An anti-collision and energy absorbing device is generally placed at the front end of railway vehicles to provide controlled collapse and sufficient energy absorbing capacity. In the conventional way, the energy absorbing device is usually designed as an integrated part of the carbody that can’t be easily replaced nor maintained after crash. To increase the maintainability and energy absorbing capacity of the energy absorbing device, a Multi-stage Crashworthiness Energy Absorbing Device has been developed, in which the first-stage and the second-stage energy absorbing units can be replaced or repaired under the collision that is not severe enough to initiate the third-stage energy absorbing unit. The Crashworthiness Energy Management (CEM) has four stages: coupler energy absorbing components (stage 1), honeycomb in the sliding center anti-climber (stage 2), metal peeling tubes mounted at the back of the fixed anti-climber (stage 3) and the structural components in the cab area (stage 4). By comparing the simulation results and test results, it is concluded that the finite element simulation model can provide dependable and accurate prediction for collision behaviors. Based on the design, simulation and test data, a safe, reliable and maintainable Multi-stage Crashworthiness Energy Absorbing Device has been verified and validated, which can provide valuable reference for researchers and engineers in the crashworthiness and railway vehicle industry.
Does intensive glycaemic control promote healing in diabetic foot ulcers? – a feasibility study
Authors: Dissanayake Ajith , Vandal Alain C , Boyle Veronica , Park Diane , Milne Bobbie , Grech Roger , Ng Anthony 
Published: January 2020

IntroductionOne in four diabetes patients will develop a foot ulcer over their lifetime. The role of glycaemic control in the healing of foot ulcers in diabetes patients is not supported by randomised controlled trial (RCT) data.ObjectivesTo determine the feasibility of an RCT of glycaemic control with intensive insulin therapy in diabetic foot ulcer, by assessing: entry criteria, fasting capillary blood glucose (FCBG) medication satisfaction and sensitivity of different ulcer-healing endpoints to glycaemic control.DesignTwo substudies: one cross-sectional and one single-arm prospective.SettingSingle-centre secondary care diabetic foot clinic in New Zealand.ParticipantsSubstudy 1: 78 participants consisting of all people ≥18 years with a diabetic foot ulcer presenting to the clinic over 35 weeks in 2015.Substudy 2: 15 participants from Substudy 1 consenting to intensive insulin therapy.InterventionSubstudy 1: None.Substudy 2: Intensive insulin therapy with standard podiatry care over 24 weeks.OutcomeSubstudy 1: Proportion of participants satisfying potential RCT entry criteria; medication satisfaction (Diabetes Medication Satisfaction).Substudy 2: FCBG, index ulcer healing time, index ulcer size, health-related quality of life (HRQoL; EuroQol 5 Dimensions 5 Levels and Diabetic Foot Ulcer Scale-Short Form).ResultsProportion in Substudy 1 satisfying all entry criteria was 31% (95% CI 21 to 42). FCBG values decreased between baseline and study end (difference −3.7 mmol/L, 95% CI −6.5 to −0.8); 83% (95% CI 44 to 95) of ulcers healed by 24 weeks. FCBG correlated negatively with medication satisfaction. Ulcer area logarithm was most sensitive to FCBG changes, displaying significant negative correlation with HRQoL outcomes. Detecting a 30% between-group difference in this outcome (80% power, α=5%) requires 220 participants per arm, achievable within 1 year with 15 centres similar to study setting.ConclusionsAn adequately powered RCT requires cooperation between a large number of centres. Ulcer area logarithm should be primary endpoint.Trial registration numberANZCTR ACTRN12617001414303
Impact and use of reviews and ‘overviews of reviews’ to inform clinical practice guideline recommendations: protocol for a methods study
Authors: Lunny Carole , Ramasubbu Cynthia , Gerrish Savannah , Liu Tracy , Salzwedel Douglas M , Puil Lorri , Mintzes Barbara , Wright James (Jim) 
Published: January 2020

IntroductionGuidelines are systematically developed recommendations to assist practitioner and patient decisions about treatments for clinical conditions. High quality and comprehensive systematic reviews and ‘overviews of systematic reviews’ (overviews) represent the best available evidence. Many guideline developers, such as the WHO and the Australian National Health and Medical Research Council, recommend the use of these research syntheses to underpin guideline recommendations. We aim to evaluate the impact and use of systematic reviews with and without pairwise meta-analysis or network meta-analyses (NMAs) and overviews in clinical practice guideline (CPG) recommendations.Methods and analysisCPGs will be retrieved from Turning Research Into Practice and Epistemonikos (2017–2018). The retrieved citations will be sorted randomly and then screened sequentially by two independent reviewers until 50 CPGs have been identified. We will include CPGs that provide at least two explicit recommendations for the management of any clinical condition. We will assess whether reviews or overviews were cited in a recommendation as part of the development process for guidelines. Data extraction will be done independently by two authors and compared. We will assess the risk of bias by examining how each guideline developed clinical recommendations. We will calculate the number and frequency of citations of reviews with or without pairwise meta-analysis, reviews with NMAs and overviews, and whether they were systematically or non-systematically developed. Results will be described, tabulated and categorised based on review type (reviews or overviews). CPGs reporting the use of the Grading of Recommendations, Assessment, Development and Evaluation approach will be compared with those using a different system, and pharmacological versus non-pharmacological CPGs will be compared.Ethics and disseminationNo ethics approval is required. We will present at the Cochrane Colloquium and the Guidelines International Network conference.
Vitamin D supplementation to improve pregnancy and perinatal outcomes: an overview of 42 systematic reviews
Authors: Bialy Liza , Fenton Tanis , Shulhan-Kilroy Jocelyn , Johnson David W , McNeil Deborah A , Hartling Lisa 
Published: January 2020

ObjectiveTo review the evidence to assess effectiveness of vitamin D supplementation during pregnancy and associations of serum vitamin D levels with perinatal outcomes.DesignOverview of systematic reviews (SRs).Data sourcesSearches conducted in January 2019: Ovid Medline (1946–), Cochrane Library databases.Eligibility criteria for selecting studiesTwo reviewers independently screened titles and abstracts, and full texts using predefined inclusion criteria: SRs evaluating vitamin D supplementation in pregnant women and/or examining the association between serum vitamin D levels reporting at least one predefined perinatal outcome. Only SRs with high AMSTAR scores were analysed.Data extraction and synthesisData were extracted independently by one reviewer and checked by a second. Results were assessed for quality independently by two reviewers using GRADE criteria.ResultsThirteen SRs were included, synthesising evidence from 204 unique primary studies. SRs of randomised controlled trials (RCTs) with the highest level of evidence showed no significant benefit from vitamin D in terms of preterm birth (RR 1.00 (95% CI 0.77, 1.30); high quality), pre-eclampsia (RR 0.91 (0.45, 1.86); low quality), gestational diabetes (RR 0.65 (0.39, 1.08); very low quality), stillbirth (RR 0.75 (0.50, 1.12); high quality), low birth weight (RR 0.74 (0.47, 1.16); low quality), caesarean section (RR 1.02 (0.93, 1.12); high quality). A significant difference was found for small for gestational age (RR 0.72 (0.52, 0.99); low quality). SRs of observational studies showed associations between vitamin D levels and preterm birth (RR 1.19 (1.08, 1.31); moderate quality), pre-eclampsia (RR 1.57 (1.21, 2.03) for 25-hydroxy vitamin D (25 (OH)D)<50 nmol/L subgroup; low quality), gestational diabetes (RR 1.12 (1.02, 1.22) for 25 (OH)D<50 nmol/L and RR 1.09 (1.03, 1.15)<75 nmol/L; moderate quality) and small for gestational age (RR 1.35 (1.18, 1.54)<50 nmol/L; low quality). SRs showed mixed results for associations between vitamin D and low birth weight (very low quality) and caesarean section (very low quality).ConclusionThere is some evidence from SRs of observational studies for associations between vitamin D serum levels and some outcomes; however SRs examining effectiveness from RCTs showed no effect of vitamin D supplementation in pregnancy with the exception of one predefined outcome, which had low quality evidence. Credibility of the evidence in this field is compromised by study limitations (in particular, the possibility of confounding among observational studies), inconsistency, imprecision and potential for reporting and publication biases.
Educational differentials in key domains of physical activity by ethnicity, age and sex: a cross-sectional study of over 40 000 participants in the UK household longitudinal study (2013–2015)
Authors: Fluharty Meg E , Pinto Pereira Snehal M , Benzeval Michaela , Hamer Mark , Jefferis Barbara , Griffiths Lucy J , Cooper Rachel , Bann David 
Published: January 2020

ObjectivesTo assess whether educational differentials in three key physical activity (PA) domains vary by age, sex and ethnicity.DesignNational cross-sectional survey.SettingUK.ParticipantsAltogether 40 270 participants, aged 20 years and over, from the UK Household Longitudinal Study with information on education, PA and demographics collected in 2013–2015.Outcome measuresParticipation in active travel (AT), occupational activity (OA) and leisure time physical activity (LTPA) at the time of assessment.ResultsLower educational attainment was associated with higher AT and OA, but lower weekly LTPA activity; these associations were modified by sex, ethnicity and age. Education-related differences in AT were larger for women—the difference in predicted probability of activity between the highest and the lowest education groups was −10% in women (95% CI: −11.9% to 7.9%) and −3% in men (−4.8% to –0.4%). Education-related differences in OA were larger among men −35% (-36.9% to –32.4%) than women −17% (-19.4% to –15.0%). Finally, education-related differences in moderate-to-vigorous LTPA varied by ethnicity; for example, differences were 17% (16.2% to 18.7%) for white individuals compared with 6% (0.6% to 11.6%) for black individuals.ConclusionsEducational differences in PA vary by domain and are modified by age, sex and ethnicity. A better understanding of physically inactive subgroups may aid development of interventions to both increase activity levels and reduce health inequalities.