bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study of Forming Efficiency by Real-time Correction of Head Nozzle Height in Directed Energy Deposition
Authors: Aizawa Kengo , Ueda Masahiro , Aoyama Hideki , Yamazaki Kazuo 
Published: July 2020

Abstract
Laser metal deposition is of two types: powder bed and metal deposition. Either method is expected to be a breakthrough in innovative design and manufacturing technology development because both methods can form shapes that cannot be formed by conventional removal processing. One metal deposition method is directed energy deposition (DED), in which a laser irradiates the target position on the metal layer to melt it, and metal powder is supplied to the target position to perform molding. DED is expected to produce large parts and repair molds. However, as the lamination mechanism is not sufficiently clarified, relationships between process parameters, material properties, molding accuracy, and molding efficiency are not clear, making stable molding difficult [1]One obstacle to stable molding is that the distance between the head nozzle that supplies the metal powder and the molten pool cannot currently be kept constant. In this study, we measure the distance between the head nozzle and the molten pool using a triangulation method, propose a method to control the position of the head nozzle to keep the distance constant, and experimentally verify the method’s usefulness.
Effect of Segment Thickness on Internal Force of Shield Tunnel under Abnormal Loading Conditions
Authors: Zhang Bolin , Zheng Jun 
Published: July 2020

Abstract
Segment thickness is one of the important parameters of shield tunnel structure design. Segment thickness determines the section stiffness and mechanical performance of shield tunnel structure. Considering the load type of overload and unload, a three-dimensional fine shield tunnel numerical model was established. The full-scale test was used to verify the correctness of the numerical model. In the end, the effect of segment thickness on the internal force of shield tunnel structure under abnormal loading conditions was analyzed. The results show that the internal force of each section of the tunnel structure increases with the increase of the thickness of the segment, and the difference of the internal force between the different segment thickness increases with the increase of the overload and the degree of unloading. Increasing the thickness of segment will delay the breakpoint of the bending moment and axial force (critical instability state). The excessive increase of the segment thickness can lead to a large increase in the internal force of the tunnel structure, resulting in a decrease in the crack resistance of the tunnel structure.
Effects of Friction Stir Welding Parameters of Dissimilar Aluminum Alloys on Residual Stress and Microhardness
Authors: Baisukhan Adirek , Nakkiew Wasawat 
Published: July 2020

Abstract
The aim of this research is to use a full factorial design to determine the significant factors of friction stir welding (FSW) process of dissimilar AA6061-T6 and AA7075-T651 aluminum alloys, on the surface residual stress and microhardness. There are a total of three factors studied: rotation speed, welding speed and workpiece layout. The results showed that the factors that have a statistically significant effect on residual stress occurring are welding speed, workpiece layout and interaction between rotation speed and welding speed. The appropriate parameters for FSW process of dissimilar aluminum alloys are rotation speed of 1400 rpm, welding speed of 50 mm/min and the layout of the workpiece by advancing side (AS) uses AA6061-T6 sheet, while retreating side (RS) uses AA7075-T651 sheet, which will result in the surface residual stress of −34.33 MPa. This compressive residual stress will be beneficial to the welded joint for retard the occurrence of cracks caused by fatigue. The hardness of all workpieces have similar tendency, thermo-mechanically affected zone (TMAZ) area in both AS and RS gave the least hardness, which found that the AA6061-T6 and AA7075-T651 sheets had a hardness of approximately 55HV and 110HV respectively.
Deformation behavior study in a model dual phase system of copper–martensitic steel using in-situ synchrotron X-ray diffraction
Authors: Teimouri M , Godfrey A , Yu B , Tsuji N 
Published: July 2020

Abstract
In this study, the deformation behavior of two phases in a model dual phase system of copper and a martensitic stainless steel was investigated using in situ synchrotron X-ray diffraction. Due to the different crystallographic structures of copper and martensite, their diffraction patterns are well separated such that the strain distribution and the load partitioning between the phases could be investigated under loading using standard methods. The copper matrix started to yield at low stress levels after a short stage of elastic deformation and the different lattice strain of the copper and martensite indicated that load partitioning took place after yielding of the copper.
Remaining Useful Life Prediction of Lithium-ion Battery based on Attention Mechanism with Positional Encoding
Authors: Zhou Beitong , Cheng Cheng , Ma Guijun , Zhang Yong 
Published: July 2020

AbstractThe rising demands of more reliable and stable electrical systems attach importance to accurate Remaining Useful Life (RUL) prediction of the lithium-ion batteries. As artificial intelligence and machine learning techniques advance, data-driven methods especially deep learning algorithms have become the rising star in RUL prediction. Recurrent Neural Networks (RNNs) and their variants such as Long Short Term Memory have proven effectiveness in various sequential tasks. However, due to its iterative nature along the time axis, RNNs take much time for information to flow through the network for prediction. Inspired by recent advance brought by Transformer in sequence transduction tasks, we proposed the attention mechanism based Convolutional Neural Network (CNN) with positional encoding to tackle this problem. The attention mechanism enables the network to focus on specific parts of sequences and positional encoding injects position information while utilizing the parallelization merits of CNN on GPUs. Empirical experiments show that the proposed approach is both time effective and accurate in battery RUL prediction.
Static characteristics of a simple rotor-bearing system: modelling and experiment
Authors: Dang Phuoc Vinh , Minh Nhat Le Dinh , Vo Nhu Thanh , Ngo Thanh Nghi , Le Hoai Nam , Nguyen Huu Nhan 
Published: July 2020

Abstract
The dynamics of rotating machinery have been extensively investigated during the past century. To date, longer rotating shafts, higher rotating velocity, higher fluid pressure, and generally high performances are required. For this purpose, a deep understanding and a more accurate modelling of the rotating machinery dynamical behaviour is needed, especially in terms of the resultant vibrations and stability issues. In this paper, a mathematical model was developed for a simple rigid rotor-bearing system using finite element method. Several natural frequencies and corresponding mode shapes of the systems were presented. In order to validate the model, some experimental tests were performed using a small test rig. The response of the system in the frequency domain and the direct orbit of the shaft were plotted as well.
Empirical study on influences of electromagnetic field on Hall Effect sensor for analysing oil lubricant deterioration
Authors: Satthamsakul S , Sriratana W , Sriratana L 
Published: July 2020

Abstract
This study aims to present the procedure developed for detecting deterioration of oil lubricant under variation of electromagnetic field which was generated by a ferrite-core solenoid coil. The overall diameter of coil was 18.5 mm and the inductance was 22.421 mH from direct current stimulation. The results were then compared to those from frequency stimulation. The optimal efficiency of measurement systems was then assessed by real-time analyzing the metal particle contamination of 3 oil lubricants categorized by grade namely ISO 32, ISO 46 and ISO 68 as well as the viscosity under specific conditions which were flow rate and temperature ranging from 25 °C to 100 °C. The analysis was performed to compare the results from experiments of unused and used (approximately 6 months) oil lubricants. From experiments, the viscosity of oil lubricant was reduced when the temperature exceeded 50 °C. However, the stimulation of coil using 0.9 A direct current could clearly distinguish the difference between the unused and used oil lubricants with metal particle contamination comparing to other values of direct currents applied with 0.42 % of error. Also, the 0.5 kHz of frequency would be the most appropriate value for frequency stimulation with 0.38 % of error.
Preparation and photochromic properties of phosphomolybdic acid/rare earth strontium aluminate luminous fiber
Authors: Li Jing , Tang Sisi , Ge Mingqiao , Zhu Yanan , Yu Yuan 
Published: July 2020

Abstract
In this study, we intend to obtain a novel luminous fiber with colour-tuned luminescence via the photoelectron transfer of a phosphomolybdic acid pigment (PAP). The luminous fiber include the SrAl2O4: Eu2+, Dy3+ materials as the luminescence sources, a solid solution of PAP and polyvinyl alcohol as the photoinitiator, amino silicone resin (ASR) as the surface-modified film-forming material and polypropylene (PP) as the matrix, which are prepared by the melt spinning method. The surface morphology was characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV–vis) spectroscopy, photoluminescence emission spectroscopy, and CIE-1931 chromaticity coordinates. Thus, promising results were obtained, which denoted that the luminescence colour of the luminous fibers could transform from yellow–green to blue by adjusting the PAP concentration. The PL emission spectra of these luminous fibers consisted of two emission peak regions in the range of 430–530 nm. The intensity of the two emission peaks in the fiber reaches the maximum when the concentration of the PAP was 50%. Further, the fibers gradually turned blue with luminescence decay when the fiber was placed in a dark place. The existence of photosensitive discoloration was found to be directly related to the amino groups embedded in the silicone resin coated with the luminous surface material, which reacted with PAP to develop phosphorous molybdenum blue via the photo-reduction process. These findings provide valuable insights toward developing next-generation luminescent materials and multicolor luminous fibers.
Surface defects incorporated diamond machining of silicon
Authors: Khatri Neha , Barkachary Borad M , Muneeswaran B , Al-Sayegh Rajab , Luo Xichun , Goel Saurav 
Published: July 2020

Abstract
This paper reports the performance enhancement benefits in diamond turning of the silicon wafer by incorporation of the surface defect machining (SDM) method. The hybrid micromachining methods usually require additional hardware to leverage the added advantage of hybrid technologies such as laser heating, cryogenic cooling, electric pulse or ultrasonic elliptical vibration. The SDM method tested in this paper does not require any such additional baggage and is easy to implement in a sequential micro-machining mode. This paper made use of Raman spectroscopy data, average surface roughness data and imaging data of the cutting chips of silicon for drawing a comparison between conventional single-point diamond turning (SPDT) and SDM while incorporating surface defects in the (i) circumferential and (ii) radial directions. Complementary 3D finite element analysis (FEA) was performed to analyse the cutting forces and the evolution of residual stress on the machined wafer. It was found that the surface defects generated in the circumferential direction with an interspacing of 1 mm revealed the lowest average surface roughness (Ra) of 3.2 nm as opposed to 8 nm Ra obtained through conventional SPDT using the same cutting parameters. The observation of the Raman spectroscopy performed on the cutting chips showed remnants of phase transformation during the micromachining process in all cases. FEA was used to extract quantifiable information about the residual stress as well as the sub-surface integrity and it was discovered that the grooves made in the circumferential direction gave the best machining performance. The information being reported here is expected to provide an avalanche of opportunities in the SPDT area for low-cost machining solution for a range of other nominal hard, brittle materials such as SiC, ZnSe and GaAs as well as hard steels.
Microstructure-based three-dimensional characterization of chip formation and surface generation in the machining of particulate-reinforced metal matrix composites
Authors: Wu Qi , Zhang Liangchi 
Published: July 2020

Abstract
Particulate-reinforced metal matrix composites (PRMMCs) are difficult to machine due to the inclusion of hard, brittle reinforcing particles. Existing experimental investigations rarely reveal the complex material removal mechanisms (MRMs) involved in the machining of PRMMCs. This paper develops a three-dimensional (3D) microstructure-based model for investigating the MRM and surface integrity of machined PRMMCs. To accurately mimic the actual microstructure of a PRMMC, polyhedrons were randomly distributed inside the matrix to represent irregular SiC particles. Particle fracture and matrix deformation and failure were taken into account. For the model’s capability comparison, a two-dimensional (2D) analysis was also conducted. Relevant cutting experiments showed that the established 3D model accurately predicted the material removal, chip morphology, machined surface finish, and cutting forces. It was found that the matrix-particle-tool interactions led to particle fractures, mainly in the primary shear and secondary deformation zones along the cutting path and beneath the machined surface. Particle fracture and dilodegment greatly influences the quality of a machined surface. It was also found that although a 2D model can reflect certain material removal features, its ability to predict microstructural variation is limited.
Uncovering interpretable relationships in high-dimensional scientific data through function preserving projections
Authors: Liu Shusen , Anirudh Rushil , Thiagarajan Jayaraman J , Bremer Peer-Timo 
Published: July 2020

Abstract
In many fields of science and engineering, we frequently encounter experiments or simulations datasets that describe the behavior of complex systems and uncovering human interpretable patterns between their inputs and outputs via exploratory data analysis is essential for building intuition and facilitating discovery. Often, we resort to 2D embeddings for examining these high-dimensional relationships (e.g. dimensionality reduction). However, most existing embedding methods treat the dimensions as coordinates for samples in a high-dimensional space, which fail to capture the potential functional relationships, and the few methods that do take function into consideration either only focus on linear patterns or produce non-linear embeddings that are hard to interpret. To address these challenges, we proposed function preserving projections (FPP), which construct 2D linear embeddings optimized to reveal interpretable yet potentially non-linear patterns between the domain and the range of a high-dimensional function. The intuition here is that humans are good at understanding potentially non-linear patterns in 2D but unable to interpret non-linear mapping from high-dimensional space to 2D. Therefore, we should restrict the projection to linear but not the pattern we are seeking. Using FPP on real-world datasets, one can obtain fundamentally new insights about high-dimensional relationships in extremely large datasets that could not be processed with existing dimension reduction methods.
Surface functionalization of multi-walled carbon nanotubes by ozone and the enhancement of their environmental applications
Authors: Elsehly Emad M , Chechenin N G , Makunin A V , Shemukhin A A , Motaweh H A 
Published: July 2020

Abstract
Selective functionalization of multiwalled carbon nanotubes (MWNTs) is essential for many prospective applications of such materials. In the present study, MWNTs grown by chemical vapor deposition are functionalized by ozone treatment at room temperature. Through this environmental and effective functionalization method, the chemical reactivity of MWNTs can be altered and tuned. Ozone functionalized MWNTs (F-MWNTs) were characterized by Raman spectroscopy, SEM, EDS, BET surface area, XPS, and FTIR. The results obtained confirm the formation of oxygen groups attached to the surface of ozone-treated nanotubes (e.g. carboxyl), which modify their physicochemical properties and boost the surface reactivity. The F-MWNT filters showed 99.5% manganese removal efficiency at 20 ppm concentration in the solution, which is higher than the efficiency reported earlier. The optimal parameters for Mn adsorption by F-MWNTs were studied. Possible mechanisms of F-MWNT adsorption processes are also discussed.
Engagement in Cognitively Stimulating Activities Mediates the Relationship between Openness and Attention/Executive Functions, but Not Memory in Older Adults
Authors: Mercuri Giulia , Holtzer Roee 
Published: July 2020

Abstract

Objective
Openness has a positive association with cognitive functioning and engagement in cognitively stimulating activities (CSA). Older adults who engage in more CSA tend to show greater preservation of their cognitive skills; thus, we examined whether: higher Openness would be associated with higher attention/executive functions (AEF) and verbal memory; and CSA would mediate the relationship between Openness and AEF, as well as verbal memory.

Method
477 community-dwelling older adults (65+ years) were included in the current cross-sectional study. Composite variables of AEF (TMT-A&B, COWAT, and DSST) and verbal memory (RBANS immediate and delayed verbal memory subtasks) were included. Openness was assessed via the Big-5 Inventory and CSA with the Leisure Activity Questionnaire.

Method
477 community-dwelling older adults (65+ years) were included in the current cross-sectional study. Composite variables of AEF (TMT-A&B, COWAT, and DSST) and verbal memory (RBANS verbal memory subtasks) were included. Openness was assessed via the Big-5 Inventory and CSA with the Leisure Activity Questionnaire.

Results
Linear regressions indicated a significant positive association between Openness and AEF (β = .09, p &lt; .01), but not verbal memory (β = .06, p = .06). A significant partial mediation was demonstrated between Openness, CSA, and AEF (c: β = .08, p &lt; .05, 95%CI = .02−.14; c′: β = .02, 95%CI = .01−.03). The mediation of Openness, CSA, and verbal memory was not significant (c: β = .06, p &gt; .05, 95%CI = .01−.11; c′: β = .00, 95%CI = −.01−.01).

Conclusions
The association between Openness and AEF, but not verbal memory, was partially mediated by CSA in healthy older adults. The findings suggest that those who are more open to and highly engaged in CSA may have a later in life advantage in preserving their AEF abilities.
PDR: a new genome assembly evaluation metric based on genetics concerns
Authors: Xie Luyu , Wong Limsoon 
Published: July 2020

Abstract

Motivation
Existing genome assembly evaluation metrics provide only limited insight on specific aspects of genome assembly quality, and sometimes even disagree with each other. For better integrative comparison between assemblies, we propose, here, a new genome assembly evaluation metric, Pairwise Distance Reconstruction (PDR). It derives from a common concern in genetic studies, and takes completeness, contiguity, and correctness into consideration. We also propose an approximation implementation to accelerate PDR computation.

Results
Our results on publicly available datasets affirm PDR’s ability to integratively assess the quality of a genome assembly. In fact, this is guaranteed by its definition. The results also indicated the error introduced by approximation is extremely small and thus negligible.

Availabilityand implementation
https://github.com/XLuyu/PDR.

Supplementary information
Supplementary data are available at Bioinformatics online.
Experimental Criminology and the Free-Rider Dilemma
Authors: Koehler Johann , Smith Tobias 
Published: July 2020

AbstractExperimental criminology promises a public good: when experiments generate findings about criminal justice interventions, everyone benefits from that knowledge. However, experimental criminology also produces a free-rider problem: when experiments test interventions on the units where problems concentrate, only the sample assumes the risk of backfire. This mismatch between who pays for criminological knowledge and who rides on it persists even after traditional critiques of experimental social science are addressed. We draw from medicine and economics to define experimental criminology’s free-rider problem and expose a dilemma. Either we distribute the costs of producing policy-actionable knowledge to the entire beneficiary population or we justify isolating the risk of experimental harm on that class of the population where ethical concerns are most acute.
Discharge, But No Exit: An Existential Qualitative Interpretive Meta-Synthesis of Veteran Reintegration
Authors: Tarbet Zachary , Moore Steven , Alanazi Ahmed 
Published: July 2020

Abstract
Ongoing campaigns in support of the Global War on Terrorism have created an influx of veterans attempting to reintegrate into civilian society. While some veterans reintegrate easily, others continue to struggle. An increasing number of studies have begun to take a more holistic approach to understanding the root causes of the distress observed in reintegrating veterans. The objective of this study was to utilise the existential framework as conceptualised by Irvin Yalom to generate a deeper understanding of the underlying factors contributing to the struggles that veterans experience in their return to society. A qualitative interpretive meta-synthesis (QIMS) approach was used to hear the combined voices of a selection of veterans from the USA and UK. A directed content analysis was used in conjunction with the QIMS methodology to categorise novel constructs in the context of existential ultimate concerns resulting in nine new themes: loss of identity, fear of death, loss of control, reliance on authority, feelings of alienation, self-isolation, resentment towards civilians, loss of collective sense of duty and loss of purpose. Findings enhance the understanding of conflicting values and beliefs underlying reintegration problems, informing future social work practice and research.