bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tribological Analysis of Squeeze Stir Cast Recycled Aluminum MMC’s
Authors: Victor Christy John , Mourad Abdel-Hamid I. , Qudeiri Jaber Abu 
Published: October 2021

Abstract
In this work, squeeze stir casting was used to produce recycled Aluminum Metal Matrix Composites (MMC’s) plates. Scrap Aluminum Alloy Wheel (SAAW) was used as a matrix and alumina as reinforcement. The produced recycled MMC plate was subjected to abrasive and sliding wear using a Two-body abrasion tester and Pin-on-Disc tester with a load of 20 N. To improve the wear resistance of the recycled MMC, graphite (1% to 4%) and SiC (3% and 6%) were added to alumina, and the results were compared. The results showed that the addition of graphite and SiC to alumina decreased the wear rate and frictional forces compared to using alumina alone as reinforcements. Also, wear rates and frictional forces further reduced by increasing the percentage of graphite to 4%, whereas increasing the SiC content increased the wear. Scanning Electron Microscopy (SEM) analysis and microstructure analysis was conducted on these samples. These results confirmed that graphite and alumina exhibited better bonding to the SAAW matrix than SiC. Since this recycled Aluminum MMC achieves a cleaner production process, it has great industrial potential, including applications in the piping industry, and its tribological properties can be boosted using graphite (4% by wt.) with alumina (5% by wt.) as reinforcements.
Further Development of Probabilistic Leak-Before-Break Methods
Authors: Gill Peter , Daniels Brian 
Published: October 2021

Abstract
Leak-before-Break software has been developed to provide probabilities of detecting a leak from a circumferential crack in a pipe. This utilizes the methods detailed in the UK structural integrity assessment procedure, R6, and was presented in PVP2020-21769. The latest developments in this code are presented in this paper and account for initial surface defects that can develop over time to become through wall cracks. This is possible through the implementation of stress intensity factor solutions for semi-elliptical circumferential flaws in cylinders of Chapuliot et. al and crack growth laws due to Stress Corrosion Cracking.
The results presented in this paper demonstrates the functionality of the code with sample problems that are designed to be plant representative. Probability of detection is also accounted for and enables reliabilities to be calculated based on probability of failure from the Monte Carlo simulations.
Equivalent Diameter for Predicting Vortex Shedding of Finned Cylinders in Cross-Flow
Authors: Alziadeh Mohammed , Mohany Atef 
Published: October 2021

Abstract
This article explores different equivalent diameter equations found in the literature for shedding frequency scaling and applying it to various types of finned cylinders in industrial heat exchangers. The focus is on three finned cylinder types: straight, twist-serrated, and crimped spirally finned cylinders. Within each finned cylinder category, at least three different finned cylinders are investigated. The results indicate that utilizing the appropriate equivalent diameter for vortex shedding frequency scaling collapses the data within the Strouhal bounds of a bare cylinder away from resonance excitation. However, the onset of flow-excited acoustic resonance and peak acoustic pressure in all the finned cylinder cases occur at a reduced flow velocity earlier than their equivalent diameter bare cylinder. This suggests that although utilizing the appropriate equivalent diameter can predict the shedding frequency away from resonance, it cannot be used in velocity scaling to predict the onset of acoustic resonance in finned tube bundle.
Technical Basis Summary for Code Case N-860: Inspection Requirements and Evaluation Standards for Spent Nuclear Fuel Storage and Transportation Containment Systems
Authors: Broussard John E. 
Published: October 2021

Abstract
ASME Boiler and Pressure Vessel Code Section XI Code Case N-860 provides inspection requirements and evaluation standard for welded stainless steel canisters used for spent nuclear fuel storage. The Code Case defines an initial inspection interval and populations then defines examination requirements that are based on the primary degradation mechanism, chloride induced stress corrosion cracking (CISCC). Additional examination requirements are based on the results of the initial screening examination. This paper summarizes the technical basis for the examinations and the evaluation criteria defined in Code Case N-860. Technical basis information for topics related to the inservice inspection and the flaw evaluation of canisters are described. The topics related to inservice inspection include: 1) the reasons for and the basis of requirements for the site susceptibility of the canister installations, 2) the inspection intervals required by the Code Case, 3) the inspection sample population required by the Code Case, 4) the methods and acceptance criteria for visual examinations required by the Code Case, and 5) the size and location of the required inspection region for supplemental examinations. The topics related to the flaw evaluation include: 1) a summary of the crack growth rate technical basis, and 2) background related to flaw size evaluation for spent fuel canisters.
Flexural Vibrations of a Multi-Material Microhydraulic Hose Subjected to External Excitation. Experimental Research and Theoretical Description
Authors: Lubecki Marek , Stosiak Michał , Bocian Mirosław , Urbanowicz Kamil 
Published: October 2021

Abstract
The paper presents experimental research and mathematical modeling of flexural vibrations of a composite hydraulic microhose. The tested object was a Polyflex 2020N-013V30 hydraulic microhose, consisting of a braided aramid layer placed in a thermoplastic matrix. The vibrations were induced with an external electromagnetic exciter in the range from 0 Hz to 100 Hz using the sweep function. Using a laser vibrometer, the exciter’s displacement was measured in the above-mentioned range. Long exposure photographs were taken to identify the form of microhose’s vibrations as well as to measure it’s amplitude. The existence of considerable non-linearity in subsequent natural frequencies was shown. At the same time, mathematical simulations were carried out using the Mathematica software. For the analytical description of the object’s vibrations partial differential equations based on the string equation were used. A part responsible for damping in the material was added to the classical equation of the string. The dependence of the values of the stiffness and damping coefficients a on the excitation frequency made it possible to model nonlinearities manifested by the upward shift of higher natural frequencies and the suppression of the amplitudes of successive modes. Further development of the proposed model will allow for modeling the internal pressure in the hose and its effect on transverse vibrations. It will also allow to design of vibrations of composite microhoses and avoid the coupling of these vibrations with external excitations.
Directed Energy Deposition of UNS S31603 Materials by Wire Arc Energy for Nuclear Application
Authors: Ahn HeeSung , Jang YoungSeob , Heo SungHo 
Published: October 2021

Abstract
GMAW (Gas Metal Arc Welding) based Wire Arc Directed Energy Deposition (WA DED) process is one of the key metal Additive Manufacturing (AM) processes. WA DED process with commercial UNS S31603 filler wires, ER316L and ER316LSi, were applied to investigate whether print deposits satisfy the requirements for manufacturing ASME safety class 1 nuclear pressure valve components. Comprehensive chemical, micro-structural, and mechanical test data on ER316L and ER316LSi print deposits were investigated. Mechanical tests include hardness, bend, CVN, room and high temperature tensile up to 525°C. The test results were compared with ASME SA-182 forging and ASME SA-351 casting valve specifications, and ASTM F3184 standard for AM UNS S31603 with powder bed fusion. From this study, it was concluded that the as-print and solution annealed deposits with ER316LSi filler wire were recommended for manufacturing ASME safety class 1 nuclear pressure valve components.
Design of a Pneumatic Growing Robot Inspired to Plants’ Roots
Authors: Bianchi Giovanni , Agoni Aldo , Cinquemani Simone 
Published: October 2021

Abstract
Although plants are usually seen as static organisms, they exhibit a wide range of movements that only in recent years have been considered as a source of inspiration for robots. The motion of roots is one of the most interesting, because they are extraordinary diggers, able to navigate in unstructured environments, finding their way around obstacles. Moreover, root growth is featured by high energy efficiency because they penetrate the soil adding new material at their tip, without moving the already grown part, preventing friction from dissipating energy and reducing the inertia. A robot inspired to roots’ growth could be employed in search and rescue operations or in environmental monitoring. In this work the design of a soft robot inspired to root’s growth is presented. The body of the robot consists of a cylindrical plastic membrane folded inside itself. When air is blown from the base, the body of the robot is inflated, and its tip is everted increasing its length. On the external surface some Velcro stripes are mounted, which keep the membrane folded. Inside the tip a head is mounted, where the mechanism controlling the direction of growth is placed. It consists of a housing for some balloons, which can be inflated selectively, and their expansion exerts a pressure on the external surface able to open the Velcro stripes. The direction of growth is controlled by selecting which balloon to inflate. The robot has been built and a kinematic model of its motion in the plane has been developed and compared with experimental results.
Modulation of Zirconia Ferroelectricity via Crystal Orientation of Pt Electrode
Authors: Zhuang Yong-Xiang , Shieh Jay , Chen Miin-Jang , Lin Hsin-Chih 
Published: October 2021

Abstract
The origin of ferroelectricity and antiferroelectricity in zirconia (ZrO2) ultrathin films has become a topic of great interest in recent years. The normal ferroelectricity in ZrO2 is widely considered to originate from the high-pressure noncentrosymmetric Pca21 orthorhombic (o) phase. While the antiferroelectric-like behavior is regarded as the result of a phase transition from the centrosymmetric and paraelectric P42/nmc tetragonal (t) phase to the ferroelectric o-phase under electrical loading. This study reports an effective technique to selectively produce a ferroelectric or antiferroelectric ZrO2 ultrathin film (∼15 nm) without compositional manipulation. The technique is based on tailoring the crystal orientation of the Pt bottom electrode on which the ZrO2 ultrathin film is deposited. By correlating the results of the XRD, HRTEM, and electric field-polarization (P-E) analyses, it is found that a cubic phase (111)-oriented Pt electrode promotes the textured growth of the ferroelectric o-phase (111) planes in the ZrO2 ultrathin film; while a random-oriented Pt electrode leads to a t-phase dominated system, resulting in an antiferroelectric-like pinched P-E hysteresis. The modulation of ZrO2 ferroelectricity via the crystal orientation of the Pt bottom electrode can be achieved with a low thermal budget (&lt; 400 °C), making it highly favorable for process integration and device scaling in a variety of nanoelectronics and nanoelectromechanical applications.
Finite Element Modeling of Bio Compatible Piezoelectric Actuator for Orthodontic Treatment
Authors: Amiri Nikta , Karami M. Amin 
Published: October 2021

Abstract
This paper presents the finite element modeling and performance evaluation of a biocompatible piezoelectric actuator using polyvinylidene fluoride (PVDF) as an effective way in accelerating teeth movement and shortening of orthodontic treatment. Polyvinylidene fluoride (PVDF) piezoelectric actuators are used as the source of mechanical vibration and energy conversion. The device has a compact design, and can be adjusted on different teeth based on patients’ needs. The finite element model is constructed by using COMSOL Multiphysics to evaluate the effectiveness of the device. The generated force on the targeted teeth for a range of DC voltages are evaluated, and thereafter a parametric study is conducted to evaluate the effect of PVDF actuator properties including its thickness and electrode area. The results show the device can generate 2.2 gr and 8.8 gr at 100 V applied voltage for 1 mm and 4 mm actuator thickness, respectively. For 1mm PVDF thickness at 100 V, the output force increases from 1 gr to 2.2 gr by increasing the active electrode area from 25 % center area to the whole surface area. The generated force of the proposed device on the targeted teeth provides an output force of 0.5 gr to 3.5 gr depending on teeth locations. The present results demonstrate the possibility of using PVDF to design piezoelectric teeth actuators.
Integrated Thin Film Supercapacitor as Multifunctional Sensor System
Authors: Petersen Jan , Geier Sebastian , Wierach Peter 
Published: October 2021

Abstract
Throughout the integration of thin-film supercapacitors into composite structures, it is not only possible to store electric energy, but also to use them as sensor systems for strain detection. This paper describes the integration of thin-film supercapacitors into a glass-fiber composite structure, as well as their analyzation under mechanical load. The results are showing that there is a strong link between the mechanical load and the impedance spectra of the supercapacitor, enabling it to act as strain sensors. To characterize the samples, a four-point bending experiment is used, which features a well-defined constant load scenario with two interesting load states, a tensile and compression state, all in one sample. On each side one structural supercapacitor is integrated, placed far away from the neutral axis near to the outside layer, to be under the highest strain possible. Additionally, the device is placed in between the middle load entry points. During the four-point bending experiment the load is kept constant to run an electrochemical impedance spectroscopy to characterize the supercapacitor. This gives an inside view of what is happening in the supercapacitor. The experiments show a strong relation between the mechanical load and the electrochemical impedance measurements.
Development of a Releasable Snap-Fit Connector Based on Shape Memory Alloy Actuators
Authors: Pagel Kenny , Wiechmann Arne , Drossel Welf-Guntram , Lachmann Lutz 
Published: October 2021

Abstract
Shape Memory Alloy (SMA) based actuator systems provide many advantages compared to conventional actuators and have already successfully established themselves on the market in various applications. The state of the art shows a large number of SMA applications in the field of joining technology. However, these are almost exclusively aimed at providing a reliable, robust but non-detachable connection using the shape memory one-way effect. Approaches to realize a releasable connection for disassembly purposes do not or hardly exist so far.
In the present paper it is investigated how shape memory alloys can be used to design releasable snap-fit connectors. Therefore, the state of the art in the field of snap-fit connectors, particularly the systems used in the automotive sector is discussed in order to find potential applications. Beyond that, the functional structure of snap-fit connectors is analyzed to determine which SMA semi-finished products are particularly suitable for this purpose. Different concepts are evaluated and a preferred variant is derived. For detail development, a numerical study will be carried out to determine the influences of various geometric parameters on the performance of the actuator. This is realized using an SMA Finite Element Analysis (FEA) model based on Auricchio’s approach, which is described in detail. Based on these results appropriately preconditioned SMA semi-finished products are produced and experimentally investigated in order to validate the model. Furthermore, several functional models of releasable snap-fit connectors are produced using additive manufacturing processes thus verifying the approach in experiments.
Simulation-Based Design and Experimental Validation of a Ferroelectret Strain Energy Harvester for Lightweight Structures
Authors: Holzmann Hendrik , Park Ye Ji , Atzrodt Heiko 
Published: October 2021

Abstract
This work covers a novel concept for piezoelectric energy harvesting for the use in lightweight design. It is motivated by a structural strain excitation in an aircraft wing caused by a dynamic pressure. The concept uses piezoelectric electrets, also called ferroelectrets. Ferroelectrets are piezoelectric polymers that show a higher ecological compatibility and a much higher structural flexibility than piezoceramics. The used ferroelectret material for piezoelectric energy conversion is fluorinated ethylene propylene (FEP) assembled in a parallel-tunnel structure that provides high transversal piezoelectric δ31-coefficients. The transformation of strain energy is realized by a metallic mechanism converting a low strain amplitude with a high structural stress to a desired high strain amplitude. Due to low stresses required in the ferroelectret material, the metallic mechanism is designed in a very light way. An analytical model is presented to show the main design parameters and a finite element model is used with the goal of investigating the power output per total energy harvester mass. The model is eventually validated with experimental results. A power output of 344.2 nW and a ratio of power per mass of 302.6 μWkg−1 can be reached for a single harvester under a realistic quasistatic load. For a suggested cluster this can be increased up to 2.6 mW/m2 which is enough to power many devices with a low power consumption.
Towards Clinically-Relevant Shape Memory Alloy Actuated Active Steerable Needle
Authors: Acharya Sharad Raj , Hutapea Parsaoran 
Published: October 2021

Abstract
The targeting error with surgical needles in percutaneous procedures is the major factor that undermines their efficacy. The limitations in trajectory correction to reduce this error during the insertion have motivated researchers to develop actuation mechanisms in needles. The study of shape memory alloy (SMA) wire actuators in needles has gathered significant interest in the past decade because of high strain density, shape memory effect and biocompatibility. An active steerable needle design with an active stylet and a compliant collet is presented. The stylet tip bends by actuating the SMA wire installed on the bending region of the stylet. The bending region is composed of polytetrafluoroethylene (PTFE) polymer attached to the machined portion of the stylet. PTFE has low stiffness and high thermal and electrical insulation that are suitable for active needle applications. The finite element analysis of the actuation of a 3.25 mm diameter active needle model showed 18% greater tip deflection in the air compared to the prototype. By improving the SMA attachment region in the prototype, increased tip deflection as well as reduced needle diameter of 2 mm (14 gauge), which is a medically applicable scale, could be achieved.
Miocene to modern hydrothermal circulation and high topography during synconvergent extension in the Cordillera Blanca, Peru
Authors: Grambling Tyler A. , Jessup Micah J. , Newell Dennis L. , Methner Katharina , Mulch Andreas , Hughes Cameron A. , Shaw Colin A. 
Published: October 2021

AbstractThe Cordillera Blanca detachment in the highest elevations of the Peruvian Andes has been accommodating synconvergent extension since the late Miocene. Stable isotope analysis of synkinematic mica from its exhumed footwall shear zone provides new constraints on deep meteoric-hydrothermal circulation during ductile deformation and regional paleoelevation. Muscovite and biotite that deformed and/or grew synkinematically in the shear zone have δ2H values of −131‰ to −58‰ and −149‰ to −98‰ (versus Vienna standard mean ocean water, VSMOW), respectively. The δ2H value difference between coexisting muscovite and biotite is consistent with equilibrium fractionation of the same fluid at the same temperature. Calculated δ2H values of water (−107‰ to −78‰) in equilibrium with these micas are indistinguishable from those of present-day, deeply circulated (9–11 km) hot spring waters emanating from the fault. Such low-δ2H fluids indicate circulation of meteoric water to the depths of the brittle-ductile transition that cannot be explained by other mechanisms. Average recharge paleoelevation for water entering the shear zone based on hydrogen isotopes was 3400 + 500/–700 m (1σ). This is near, but ~500 m below, the present-day mean elevation of the catchments feeding modern hot springs of 3965 ± 880 m, and ~700 m below the 4200 + 700/–900 m mean recharge elevation derived from δ2H values of modern surface and thermal water. The consistency between modern and ancient fault-assisted hydrothermal systems and elevation suggests that high topography, steep relief, and meteoric-hydrothermal circulation have persisted throughout the history of the Cordillera Blanca detachment system.
Presumed incipient choroidal melanoma: proposed diagnostic criteria and management
Authors: Jouhi Susanna , Al-Jamal Ranaa T , Täll Martin , Eskelin Sebastian , Kivelä Tero T 
Published: October 2021

AimsTo propose diagnostic criteria for a presumed incipient choroidal melanoma based on tumour growth rate and tumour doubling time (TDT) and to describe management of such tumours with transpupillary thermotherapy (TTT).MethodsRetrospective interventional case series of nine consecutive presumed incipient uveal melanomas diagnosed and treated with TTT in 2010–2017. Growth rate in mm/year and per cent/year in largest basal diameter (LBD) and TDT were compared with published data for uveal melanomas and growing naevi that did not transform to melanoma under long-term follow-up.ResultsThe median LBD and thickness were 1.6 mm (range 0.9–2.3) and 0.20 mm (range 0.15–0.29), respectively. The median age was 57 years (range 47–78). Seven tumours were classified as de novo melanomas and two as transformed naevi. The median time from first observation to diagnosis was 3.3 years (range 2.2–7.3), LBD growth rate 0.25 mm/year (range 0.11–0.72) and 34 per cent/year (range 10–1437), and TDT 609 days (range 97–1612). The estimates matched those reported for uveal melanoma (median TDT 521 days, 90th percentile 2192) and exceeded those for growing naevi (median growth rate 0.04 mm/year, 90th percentile 0.12; 1.1 per cent/year, 90th percentile 2.6). The predicted median age at de novo appearance was 51 years (range 32–63). No tumour grew after TTT during a median follow-up of 2.1 years (range 0.6–8.7).ConclusionsIn this series, relative growth rate and TDT best qualified as diagnostic criteria for an incipient choroidal melanoma. Too small for brachytherapy, they could be managed with TTT.