bluuebunny/crossref_metadata_2025 huggingface dataset:
Machine Setup Abnormality Detection Using Machine Vision and Deep Learning
Authors: Choudhari Sahil J. , Singh Swarit Anand , Kumar Aitha Sudheer , Desai K. A.
Published: September 2022

Machine tools can perform manufacturing operations autonomously with minimal involvement of machine operators. However, significant human expertise is required while machine setup to minimize machine faults, downtime, and scrap parts for achieving better productivity. The machine setup involves activities such as the presence/absence of a correct cutting tool in the spindle, adequate placement of workpiece on the fixture, ensuring proper coolant flow, clogging of chips, etc. The present machine shops employ skilled human operators to perform these tasks with a checklist for ensuring completeness. The outcomes of the process are dependent on the judgment, consistency, and skills of the operator. Machine vision is considered a low-cost, low-error, and higher consistency substitute for skilled humans in industrial processes involving repetition or fatiguing tasks. The existing machine vision systems developed for dimension measurement or surface defect detection application cannot detect machine setting abnormalities due to the distinct requirements. The present work explores the development of a robust algorithm by augmenting machine vision with the deep learning algorithm You Only Look Once (YOLO) to directly extract features from the captured images. The object detection algorithm based on YOLO-v2 and ResNet-50 is implemented to detect and segregate the elements of interest from different shop-floor images. The algorithm is trained using labeled image datasets generated for several machine setup abnormalities. An interactive Graphical User Interface (GUI) is developed and integrated with the model to implement the proposed framework on the manufacturing shop floor. The developed system was implemented to detect machine setup abnormalities by considering different case studies. The study demonstrated robust detection abilities of the algorithm, offering a potential solution to minimize dependence on human operators for machine setup abnormalities.
Design of Micro-Scale Periodic Surface Textures by Pulsed Laser Melting and its Influence on Wettability
Authors: Gupta Rohit , Hijam Justin , Balhara Rama , Vadali Madhu
Published: September 2022

Micro- and nano-scale surface texture plays a major role in the wetting behavior of various metallic and non-metallic components. Modifying surfaces using lasers has been widely explored to induce periodic surface textures and thus modify the wetting behavior. Most of these modifications are either through addition or ablation material, making the process uneconomical for the industries. This work presents the pulsed laser surface melting (pLSM) based modification of metallic surfaces to change the wetting behavior, wherein the material is neither removed nor added but is redistributed to create micro-scale features. The size and geometry of the redistributed material depend on the incident laser power and pulse duration and thus affect the wetting behavior. Detailed experimental study on an initially near-flat titanium alloy (Ti6Al4V) surface at various laser powers and pulse durations are presented to understand their influence on the wetting behavior. Experiments are carried out at various laser powers ranging from 120W to 300W and various pulse durations ranging from 3μs to 20μs to understand the size and geometry achievable through pLSM. The highest peak to valley height of the pLSM induced feature (2.3μm) was achieved with 10μs long laser pulses at 210W power. This single spot feature was then rastered across the surface with varying spot spacing and line spacing to generate nine textured surfaces. The corresponding transverse contact angles and the orthogonal contact angles are reported. The results show that the textured surfaces are more wettable or hydrophilic than the near-flat untextured surface of Ti6AL4V. In addition, line spacing of the raster scan in the transverse direction has a more significant impact on the contact angle than the spot spacing in the orthogonal direction. The transverse direction has uniform groove-like features, which aid wettability more than the periodic circular features in the orthogonal direction. Nonetheless, pLSM is demonstrated as a potential method to develop micro-scale surface textures to increase the wettability (hydrophilicity) of the Ti6Al4V surface.
Exploring Surface Texture Quantification in Piezo Vibration Striking Treatment (PVST) Using Topological Measures
Authors: Yesilli Melih C. , Chumley Max M. , Chen Jisheng , Khasawneh Firas A. , Guo Yang
Published: September 2022

Surface texture influences wear and tribological properties of manufactured parts, and it plays a critical role in end-user products. Therefore, quantifying the order or structure of a manufactured surface provides important information on the quality and life expectancy of the product. Although texture can be intentionally introduced to enhance aesthetics or to satisfy a design function, sometimes it is an inevitable byproduct of surface treatment processes such as Piezo Vibration Striking Treatment (PVST). Measures of order for surfaces have been characterized using statistical, spectral, and geometric approaches. For nearly hexagonal lattices, topological tools have also been used to measure the surface order. This paper explores utilizing tools from Topological Data Analysis for measuring surface texture. We compute measures of order based on optical digital microscope images of surfaces treated using PVST. These measures are applied to the grid obtained from estimating the centers of tool impacts, and they quantify the grid’s deviations from the nominal one. Our results show that TDA provides a convenient framework for characterization of pattern type that bypasses some limitations of existing tools such as difficult manual processing of the data and the need for an expert user to analyze and interpret the surface images.
The Influence of Cell Phone Usage on Dynamic Stability of the Body During Walking
Authors: Shahidian Hamed , Begg Rezaul , Ackland David C.
Published: September 2022

Dual-task walking and cell phone usage, which is associated with high cognitive load and reduced situational awareness, can increase risk of a collision, a fall event, or death. The objective of this study was to quantify the effect of dual-task cell phone talking, texting, and reading while walking on spatiotemporal gait parameters; minimum foot clearance; and dynamic stability of the lower limb joints, trunk, and head. Nineteen healthy male participants walked on an instrumented treadmill at their self-selected speed as well as walking while simultaneously (1) reading on a cell phone, (2) texting, and (3) talking on a cell phone. Gait analyses were performed using an optical motion analysis system, and dynamic stability was calculated using the Maximum Lyapunov Exponent. Dual-task cell phone usage had a significant destabilizing influence on the lower limb joints during walking. Cell phone talking while walking significantly increased step width and length and decreased minimum foot clearance height (P < .05). The findings suggest that dual-task walking and cell phone conversation may present a greater risk of a fall event than texting or reading. This may be due to the requirements for more rapid information processing and cognitive demand at the expense of motor control of joint stability.
Modular derivation of diverse, regionally discrete human posterior CNS neurons enables discovery of transcriptomic patterns
Authors: Iyer Nisha R. , Shin Junha , Cuskey Stephanie , Tian Yucheng , Nicol Noah R. , Doersch Tessa E. , Seipel Frank , McCalla Sunnie Grace , Roy Sushmita , Ashton Randolph S.
Published: September 2022

Our inability to derive the neuronal diversity that comprises the posterior central nervous system (pCNS) using human pluripotent stem cells (hPSCs) poses an impediment to understanding human neurodevelopment and disease in the hindbrain and spinal cord. Here, we establish a modular, monolayer differentiation paradigm that recapitulates both rostrocaudal (R/C) and dorsoventral (D/V) patterning, enabling derivation of diverse pCNS neurons with discrete regional specificity. First, neuromesodermal progenitors (NMPs) with discreteHOXprofiles are converted to pCNS progenitors (pCNSPs). Then, by tuning D/V signaling, pCNSPs are directed to locomotor or somatosensory neurons. Expansive single-cell RNA-sequencing (scRNA-seq) analysis coupled with a novel computational pipeline allowed us to detect hundreds of transcriptional markers within region-specific phenotypes, enabling discovery of gene expression patterns across R/C and D/V developmental axes. These findings highlight the potential of these resources to advance a mechanistic understanding of pCNS development, enhance in vitro models, and inform therapeutic strategies.
Most users do not follow political elites on Twitter; those who do show overwhelming preferences for ideological congruity
Authors: Wojcieszak Magdalena , Casas Andreu , Yu Xudong , Nagler Jonathan , Tucker Joshua A.
Published: September 2022

We offer comprehensive evidence of preferences for ideological congruity when people engage with politicians, pundits, and news organizations on social media. Using 4 years of data (2016–2019) from a random sample of 1.5 million Twitter users, we examine three behaviors studied separately to date: (i) following of in-group versus out-group elites, (ii) sharing in-group versus out-group information (retweeting), and (iii) commenting on the shared information (quote tweeting). We find that the majority of users (60%) do not follow any political elites. Those who do follow in-group elite accounts at much higher rates than out-group accounts (90 versus 10%), share information from in-group elites 13 times more frequently than from out-group elites, and often add negative comments to the shared out-group information. Conservatives are twice as likely as liberals to share in-group versus out-group content. These patterns are robust, emerge across issues and political elites, and exist regardless of users’ ideological extremity.
Matching study using health and police datasets for characterising interpersonal violence in the community of Khayelitsha, South Africa 2013–2015
Authors: Jabar Ardil , Oni Tolu , London Leslie , Cois Annibale , Matzopoulos Richard
Published: September 2022

Objectives

The Cardiff Model of data sharing for violence prevention is premised on the idea that the majority of injury cases presenting at health facilities as a result of interpersonal violence will not be reported to the police. The aim of this study was to determine the concordance between violent crimes reported to the police with violence-related injuries presenting at health facilities in Cape Town, South Africa.

Methods

We conducted a retrospective analysis of secondary cross-sectional health and police data, from three health facilities and three police stations in the community of Khayelitsha, Cape Town. 781 cases of injuries arising from interpersonal violence seen at health facilities were compared with 739 violence-related crimes reported at police stations over five separate week-long sampling periods from 2013 to 2015. Personal identifiers, name and surname, were used to match cases.

Results

Of the 708 cases presenting at health facilities, 104 (14.7%) were matched with police records. The addition of non-reported cases of violence-related injuries from the health dataset to the police-reported crime statistics resulted in an 81.7% increase in potential total violent crimes over the reporting period. Compared with incidents reported to the police, those not reported were more likely to involve male patients (difference: +47.0%; p<0.001) and sharp object injuries (difference: +24.7%; p<0.001). Push/kick/punch injuries were more frequent among reporting than non-reporting patients (difference: +17.5%; p<0.001).

Conclusion

These findings suggest that the majority of injuries arising from interpersonal violence presenting at health facilities in Khayelitsha are not reported to the police. A data-sharing model between health services and the police should be implemented to inform violence surveillance and reduction.
Development of a core outcome set and identification of patient-reportable outcomes for primary brain tumour trials: protocol for the COBra study
Authors: Retzer Ameeta , Sivell Stephanie , Scott Hannah , Nelson Annmarie , Bulbeck Helen , Seddon Kathy , Grant Robin , Adams Richard , Watts Colin , Aiyegbusi Olalekan Lee , Kearns Pamela , Cruz Rivera Samantha , Dirven Linda , Baddeley Elin , Calvert Melanie , Byrne Anthony
Published: September 2022

Introduction

Primary brain tumours, specifically gliomas, are a rare disease group. The disease and treatment negatively impacts on patients and those close to them. The high rates of physical and cognitive morbidity differ from other cancers causing reduced health-related quality of life. Glioma trials using outcomes that allow holistic analysis of treatment benefits and risks enable informed care decisions. Currently, outcome assessment in glioma trials is inconsistent, hindering evidence synthesis. A core outcome set (COS) - an agreed minimum set of outcomes to be measured and reported - may address this. International initiatives focus on defining core outcomes assessments across brain tumour types. This protocol describes the development of a COS involving UK stakeholders for use in glioma trials, applicable across glioma types, with provision to identify subsets as required. Due to stakeholder interest in data reported from the patient perspective, outcomes from the COS that can be patient-reported will be identified.

Methods and analysis

Stage I: (1) trial registry review to identify outcomes collected in glioma trials and (2) systematic review of qualitative literature exploring glioma patient and key stakeholder research priorities. Stage II: semi-structured interviews with glioma patients and caregivers. Outcome lists will be generated from stages I and II. Stage III: study team will remove duplicate items from the outcome lists and ensure accessible terminology for inclusion in the Delphi survey. Stage IV: a two-round Delphi process whereby the outcomes will be rated by key stakeholders. Stage V: a consensus meeting where participants will finalise the COS. The study team will identify the COS outcomes that can be patient-reported. Further research is needed to match patient-reported outcomes to available measures.

Ethics and dissemination

Ethical approval was obtained (REF SMREC 21/59, Cardiff University School of Medicine Research Ethics Committee). Study findings will be disseminated widely through conferences and journal publication. The final COS will be adopted and promoted by patient and carer groups and its use by funders encouraged.

PROSPERO registration number

CRD42021236979.
Perceived risk of neurodevelopmental outcomes in offspring related to psychotropic and mental illness exposures in pregnancy and breastfeeding: a cross-sectional survey of women with past or current mental illness
Authors: Bjørndal Ludvig D , Tauqeer Fatima , Heiervang Kristin S , Clausen Hanne K , Heitmann Kristine , Lupattelli Angela
Published: September 2022

Objectives

To investigate the perceived risk of psychotropic and mental illness exposures (1) during pregnancy or (2) while breastfeeding on offspring neurodevelopment, and factors associated with this perception in women with past/current mental illness.

Design

Cross-sectional, web-based study.

Setting

Nationwide in Norway, June 2020–June 2021.

Participants

Women aged 18–55 years who were pregnant, recent mothers or planning a pregnancy, and had been offered antidepressants in the last 5 years.

Primary and secondary outcome measures

Perceived risk of prenatal and breastmilk exposure to psychotropic medications and maternal mental illness on offspring neurodevelopmental outcomes.

Results

We included 448 women: 234 pregnant, 146 mothers and 68 planning a pregnancy. On a 0–10 scale, women perceived antidepressants as least harmful both (1) in pregnancy (mean score 4.2, 95% CI 3.6 to 4.8) and (2) while breastfeeding (mean score 3.8, 95% CI 3.3 to 4.4), relative to antipsychotics, anxiety/sleeping medication or antiepileptics (mean score range: 6.3–6.5 during pregnancy, 5.5–6.2 while breastfeeding). Many participants were unfamiliar with psychotropics other than antidepressants. The perceived risk of mental illness exposure exceeded that of antidepressants (mean score range 5.6–5.9) in both exposure periods. Using general linear models, factors associated with greater antidepressant risk perception in both exposure periods included having lower education, non-Norwegian native language, and employment status (range mean score difference (β): 2.07–6.07). For pregnant women and mothers, there was an inverse association between perceived risk and the perceived antidepressant effectiveness in both exposure periods (range of β: −0.18 to –0.25).

Conclusions

In women with past/current mental illness, the perceived risk of antidepressant exposure on child neurodevelopment was lower than that for maternal mental illness. Other psychotropic medications were perceived as more harmful. As medication risk perception influences the decision-making regarding treatment of mental illness, pre- and pregnancy counselling should target women with characteristics associated with higher perceived risk.
Medical injection and infusion practices among HIV-seronegative people and people living with HIV: a behavioural survey of 10 HIV testing and opportunistic infections/antiretroviral therapy sites in Cambodia
Authors: Seang Kennarey , Khim Keovathanak , Vyas Kartavya , Khuon Dyna , Saphonn Vonthanak , Gorbach Pamina
Published: September 2022

Objectives

In late 2014, an HIV outbreak occurred in rural Cambodia among villagers who received medical injections from unlicensed medical providers, justifying the need to assess medical injection practices among those who are at risk of acquiring and/or transmitting HIV. This study examined medical injection/infusion behaviours among people living with HIV (PLWH) and those who were HIV negative in Cambodia. These behaviours should be properly assessed, especially among PLWH, as their prevalence might influence a future risk of other outbreaks.

Design

A cross-sectional survey was conducted in order to examine injection behaviours and estimate injection prevalence and rates by HIV status. Unsafe injections/infusions were those received from village providers who do not work at a health centre or hospital, or traditional providers at the participant’s (self-injection included) or provider’s home. Logistic regression was performed to examine the relationship between unsafe injection/infusion and HIV, adjusting for sex, age, education, occupation, residence location and other risk factors.

Setting

The survey was conducted in 10 HIV testing and treatment hospitals/clinics across selected provinces in Cambodia, from February to March 2017.

Participants

A total number of 500 volunteers participated in the survey, 250 PLWH and 250 HIV-negative individuals.

Outcome measures

Measures of injection prevalence and other risk behaviours were based on self-reports.

Results

Both groups of participants reported similar past year’s injection/infusion use, 47% (n=66) among PLWH and 54% (n=110) HIV-negative participants (p=0.24). However, 15% (n=11) of PLWH reported having received unsafe last injection compared with only 7% (n=11) of HIV-negative participants. In logistic regression, this association remained numerically positive, but was not statistically significant (adjusted OR 1.84 (95% CI: 0.71 to 4.80)).

Conclusions

The inclination for medical injections and infusions (unsafe at times) among PLWH and the general population in Cambodia was common and could possibly represent yet another opportunity for parenteral transmission outbreak.
Delayed diagnosis of serious paediatric conditions in 13 regional emergency departments
Authors: Michelson Kenneth A , McGarghan Finn L E , Patterson Emma E , Samuels-Kalow Margaret E , Waltzman Mark L , Greco Kimberly F
Published: September 2022

Objective

To evaluate rates, risk factors and outcomes of delayed diagnosis of seven serious paediatric conditions.

Methods

This was a retrospective, cross-sectional study of children under 21 years old visiting 13 community and tertiary emergency departments (EDs) with appendicitis, bacterial meningitis, intussusception, mastoiditis, ovarian torsion, sepsis or testicular torsion. Delayed diagnosis was defined as having a previous ED encounter within 1 week in which the condition was present per case review. Patients with delayed diagnosis were each matched to four control patients without delay by condition, facility and age. Conditional logistic regression models evaluated risk factors of delay. Complications were compared between by delayed diagnosis status.

Results

Among 14 972 children, delayed diagnosis occurred in 1.1% (range 0.3% for sepsis to 2.6% for ovarian torsion). Hispanic (matched OR 2.71, 95% CI 1.69 to 4.35) and non-Hispanic black (OR 2.40, 95% CI 1.21 to 4.79) race/ethnicity were associated with delayed diagnosis, whereas Asian and other race/ethnicity were not. Public (OR 2.21, 95% CI 1.42 to 3.44) and other (OR 2.43, 95% CI 1.50 to 3.93) insurance were also associated with delay. Non-English language was associated with delay (OR 1.65, 95% CI 1.02 to 2.69). Abnormal vital signs were associated with a lower likelihood of delay (OR 0.15, 95% CI 0.09 to 0.25). In an adjusted model, Hispanic race/ethnicity, other insurance, abnormal vital signs and complex chronic conditions (CCCs) were associated with delay. The odds of a complication were 2.5-fold (95% CI 1.6 to 3.8) higher among patients with a delay.

Conclusion

Delayed diagnosis was uncommon across 13 regional EDs but was more likely among children with Hispanic ethnicity, CCCs or normal vital signs. Delays were associated with a higher risk of complications.
Poly(2-methoxyethyl acrylate) (PMEA) improves the thromboresistance of FRED flow diverters: a thrombogenic evaluation of flow diverters with human blood under flow conditions
Authors: Yoshizawa Keiko , Kobayashi Hirohisa , Kaneki Atsushi , Takenouchi Mika , Belletto John , Baldwin Aaron , Anzai Takao
Published: September 2022

Background

Surface modification of flow-diverting stents has been explored to reduce thrombus-related complications that may arise under clinical use. This study investigated the thromboresistant properties of the flow redirection endoluminal device (FRED) X, a flow diverter treated with a copolymer of poly(2-methoxyethyl acrylate) (PMEA; X Technology).

Methods

The performance of FRED, FRED X, and Pipeline Flex with Shield Technology (sPED) was evaluated in an in vitro blood loop model. Blood activation level was assessed by the concentration of thrombin-antithrombin complex (TAT), β-thromboglobulin (β-TG), and platelet count, and qualitatively by scanning electron microscopy (SEM). Cellular adhesion characteristics were measured using human aortic endothelial cells that were seeded on flat sheets mimicking the surface of FRED, FRED X, and sPED, and evaluated with fluorescence microscopy. Statistical comparisons were conducted using one-way analysis of variance (ANOVA) with Tukey post hoc tests.

Results

FRED X, sPED, and control blood loops showed significantly reduced blood activation levels (TAT and β-TG) compared with FRED (p<0.01). Consequently, FRED showed a significant decrease in platelet count compared with FRED X, sPED, and control loops (p<0.01). SEM imaging showed the lowest accumulation of blood cell-like deposits on FRED X compared with sPED and FRED, while FRED had the highest accumulation. Endothelial cells adhered and were widely spread on X Technology-treated sheets, while minimal cell adhesion was observed on phosphorylcholine-treated sheets.

Conclusion

The X Technology surface modification of FRED X demonstrated superior thromboresistant properties over untreated FRED while maintaining comparable cellular adhesion. Taken together, these properties may help mitigate material-related thromboembolic complications.
Validation of an optical potential for incident and emitted low-energy $$\alpha $$–particles in the $$A$$ $$\sim $$60 mass range
Authors: Avrigeanu V. , Avrigeanu M.
Published: September 2022

The assessment of an $$\alpha $$
α
-particle optical model potential for nucleon–induced $$\alpha $$
α
-emission within the $$A$$
A
$$\sim $$
∼
60 mass-number range [Avrigeanu and Avrigeanu (Eur. Phys. J. A 57:54, 2021)] is completed by analysis of neutron–induced reactions on stable Ni isotopes. The same consistent set of nuclear–model input parameters as well as first uncertainty analysis of calculated cross sections related to the accuracy of independent data formerly used within parameter setting up have been concerned. Description of absorption and emission of $$\alpha $$
α
-particles by the same potential is validated, while the pickup direct reaction and Giant Quadrupole Resonance (GQR) $$\alpha $$
α
-emission beyond the statistical predictions are confirmed by recent data around the GQR energies.
Beyond the infrared: a centenary of Heinrich Rubens’s death
Authors: de Arrieta Iñigo González
Published: September 2022

Heinrich Rubens (Wiesbaden, 1865, Berlin, 1922) was the first scientist to study the large gap between the conventional infrared range and the electrical wave regime, better known today as the terahertz gap. To this end, he produced numerous original instruments and was almost single-handedly responsible for all research on this region up to the 1920s. His research, motivated by Hertz’s demonstration of the electromagnetic theory of light, led him to contribute seminal works on blackbody radiation and interferometric spectroscopy that have been almost forgotten in modern expositions of these topics. On occasion of the centenary of his death, this work aims to critically assess his legacy, as well as to revitalize this important figure for a newer generation of spectroscopists.
Accelerated innovation in developing high-performance metal halide perovskite solar cell using machine learning
Authors: Kumar Anjan , Singh Sangeeta , Mohammed Mustafa K. A. , Sharma Dilip Kumar
Published: September 2022

The invention of novel light-harvesting materials is one of the primary reasons behind the acceleration of current scientific advancement and technological innovation in the solar sector. Organometal halide perovskite (OHP) has recently attracted a great deal of interest because of the high-energy conversion efficiency that has reached within a few years of its discovery and development. Modern machine learning (ML) technology is quickly advancing in a variety of fields, providing blueprints for the discovery and rational design of new and improved material properties. In this paper, we apply ML to optimize the material composition of OHPs, propose design methods and forecast their performance. Our ML model is built using 285 datasets that were taken from about 700 experimental articles. We have developed two different ML models to predict the bandgap and performance parameters of solar cell. In the first model, we employed three ML algorithms to investigate the relationship between bandgap and perovskite material composition. We estimated the performance characteristics using projected and actual bandgap. Second, ML models are used to predict the performance parameters employing the bandgap of perovskite and energy difference between electron transport layer (ETL) and hole transport layer (HTL) with perovskite as an input parameter. Simulation results suggest that the artificial neural network (ANN) technique, which predicts the bandgap by taking into consideration how cations and halide ions interact with one another, demonstrates a better degree of accuracy (with a Pearson coefficient of 0.91 and root mean square error of 0.059). The constructed ML model closely fits the theoretical prediction made by Shockley and Queisser, and that is almost hard for a person to discover from an aggregation of datasets.
Closed form wave profiles of the coupled-Higgs equation via the ϕ6-model expansion method
Authors: Ali Karmina K. , Tarla Sibel , Yusuf Abdullahi , Yilmazer Resat
Published: September 2022

The coupled-Higgs equation, which depicts a system of preserved scalar nucleons cooperating with unbiased scalar mesons, is investigated using the [Formula: see text]-model expansion approach in this paper. We want to look at the various particles that are created when scalar nucleons collide with unbiased scalar mesons. The modulus of the elliptic function [Formula: see text] and [Formula: see text] is used to obtain the trigonometric and hyperbolic functions. Under the stated limited constraints, all found solutions are used to validate the partial differential equation. We displayed 3D surfaces and 2D visuals of selected solutions produced with the assistance of a computer program to shed more light on the dynamic behavior of the acquired solutions.
Comparative study of microstructure and mechanical properties using a novel filler rod ER 4943 and autogenously butt welded joint during laser welding of AA 6061-T6 in 1G position
Authors: Muneer Waqas , Hu Ke , Chen Shuai , Liu Dongtao , Liu Ting , Zhan Xiaohong
Published: September 2022

A 4 mm thick heat-treated aluminum alloy AA 6061-T6 has been butt welded in 1 G position using a 12-kW disk laser. A novel high magnesium content filler rod ER 4943 belonging to the 4xxx series of aluminum alloys has been used to investigate its effects on microstructure, mechanical properties and alloying elements segregation in the fusion zone. The results have also been compared with an autogenous laser butt welded joint case. A solidified microstructure has been analyzed by EBSD. It was found that additional solute content brought by filler rod into the molten pool caused a higher proportion of equiaxed grain zone after solidification due to an enhanced constitutional supercooling ahead of solid/liquid interface. For an autogenous butt welded joint, the columnar morphology sustained for a longer period and a narrower equiaxed grain zone were observed. Point analysis by an EDS revealed a higher retention of magnesium and silicon inside the solid solution with filler rod welding. In addition, the area map of magnesium also observed a denser distribution of magnesium inside the fusion zone. Both hardness and tensile strength of filler rod welded joint were higher than without filler rod welding. It is believed that a higher proportion of equiaxed grains and additional solute content within the solid solution are the primary causes of higher mechanical properties owing to hampered dislocation motion. The much desirable results obtained in terms of microstructure and mechanical properties could be of great significance to the welding industry.
Microstructure and mechanical properties during dissimilar welding of AA2060-T8 and AA6061-T6 by circular laser beam oscillations
Authors: Muneer Waqas , Hu Ke , he Shi , Chen Shuai , Zhan Xiaohong
Published: September 2022

Circular laser beam oscillations have been applied at 0.5 mm and 1 mm amplitude with four different frequencies of 30, 60, 100 and 200 Hz during dissimilar laser beam welding of 2-mm-thick heat-treated AA2060-T8 with AA6061-T6. The results have been compared with a rectilinear welding case. The width of solidified weld beads produced by laser beam oscillations is wider than that of rectilinear welding due to an increase in the area of the processed zone. Welding defects inside the fusion zone were evaluated by subjecting the joints to 100% of X-ray examination, and it was found that there was absolutely no crack and negligible level of porosity in the fusion zone. Laser beam oscillations have been applied the first time to investigate the evolution of the dendritic equiaxed zone in the central region as well as the nondendritic equiaxed zone besides the fusion line in case of 2060-T8. Optical microscopy was employed to observe the microstructure. It was found that laser beam oscillations have a significant positive impact on the microstructure both in the central region and in the vicinity of the fusion line. The inhibited ability of the formation of equiaxed dendrites due to lesser solute content has been compensated by altering the thermal conditions inside the fusion zone, and a wider equiaxed dendritic region has been achieved. In addition, the nondendritic equiaxed zone, which is undesirable during welding of aluminum–lithium alloys, has been significantly reduced in width by employing laser beam oscillations. In case of rectilinear welding, the average width of the nondendritic equiaxed zone was found to be 43 [Formula: see text]m, while the oscillatory welding reported an average width of the nondendritic equiaxed zone as low as 6 [Formula: see text]m. Enhanced fluid flow inside the melt pool and repeated interaction of the beam with the molten pool are the most probable causes of the observed results. This investigation suggests that laser beam oscillations can be successfully used to alter the microstructure and produce high-quality welds using AA 2060-T8/6061-T6 and can be replaced with conventional rectilinear laser welding for industrial applications.
A Secure Two-Tier Domain Verification and Certificate Validation Integrating Intermediate Certificate Authorities and Secure Certificate Box
Authors: Rahoof P. P. , Nair Latha R. , Thafasal Ijyas V. P.
Published: September 2022

Digital certificates play a key role in the public key infrastructure (PKI). They are mainly used to secure communication between a browser and a webserver to keep the transmitted data safe from interception. Digital certificates are issued by certificate authorities (CAs). Numerous CAs serve as root CAs around the world. Moreover, root CAs can delegate intermediate CAs (ICAs). Any CA can issue a certificate for any entity on the internet world. However, it will be difficult for an end user to identify which authorities are trustworthy and genuine. In addition, adversaries can quickly induce fraudulent certificates due to a lack of rigorous background checks for domain possession at the time of certificate issuance. Our work is primarily oriented towards incorporating the domain validation and certificate validity check from the client side as an additional security fortification. This is in addition to a novel associative approach for domain validation using ICAs. This paper presents a novel two-tier system for domain validation of servers. The system operates at two levels. At the first level, an associative validation of the domains by making use of multiple ICAs is employed. A set of CAs validates domain ownership before issuing the certificate to prevent false issuance of the certificate. In addition to this, during the initiation of the client–server connection, the client itself validates the certificate to make sure that the certificate received securely from any webserver is a genuine one.
Parallel Ensemble Matching Based on Subscription Partitioning for Content-Based Publish/Subscribe Systems
Authors: Li Junshen , Deng Yufeng , Qian Shiyou , Cao Jian , Xue Guangtao
Published: September 2022

The content-based publish/subscribe system is an effective paradigm for implementing on-demand event distribution. Each event needs to be matched against subscriptions to identify the target subscribers. To improve the matching performance, many novel data structures have been proposed. However, the predicates contained in subscriptions are handled the same way in most existing data structures, without considering their differences in matching probability. In this paper, we propose the concept of parallel ensemble matching (PEM) based on subscription partitioning. The basic idea is that we have the right algorithm handling the right subscriptions at the right time. First of all, we design a PEM framework by classifying subscriptions according to their matching probabilities and use the proper algorithms to process each subscription category. Furthermore, to deal with high-dimensional subscriptions, we propose a fine-grained PEM (fgPEM) that exploits matching algorithms with complementary behaviors by partitioning subscriptions into sub-subscriptions. We implement the prototype of PEM and fgPEM based on two existing algorithms. The experiment results show that PEM improves the matching performance by 43%. On the basis of PEM, fgPEM further improves the performance by 31%.
IMPROVED NOISE-RESILIENT ISOLATED WORDS SPEECH RECOGNITION USING PIECEWISE DIFFERENTIATION
Authors: AL-ANZI FAWAZ S.
Published: September 2022

Speech is the primary method of communication among humans; it is the main form of communication to deliver emotions and thoughts. Intuitively, humans would find it convenient to communicate with machines through speech. The automatic speech recognition model’s primary goal is to transcribe or identify the word sequence represented by the acoustic signals or speech. In this advanced era of digital media and e-learning platforms, the effective use of voice recognition technology to deliver a more individualized and effective educational experience in e-learning initiatives. It helps the students to improve their oral pronunciation skills. Even though Arabic is one of the most spoken languages, the research works related to Arabic speech and text are lacking when compared to other languages. Here, we propose a hybrid model of [Formula: see text]-Nearest Neighbor (KNN) classifier and Dynamic Time Warping (DTW) for implementing a noise-resilient speech recognition system for isolated words in the Arabic language. The model is implemented with Mel-Frequency Cepstral Coefficients (MFCC) and its piecewise first and second derivatives as feature representation models. The proposed model is implemented in Python and simulated using Arabic Speech Corpus for Isolated Words [A. Alalshekmubarak and L. Smith, On improving the classification capability of reservoir computing for Arabic speech recognition, in International Conference on Artificial Neural Networks (Springer, Cham, 2014), pp. 225–232]. The proposed model is implemented with (1) MFCC alone for feature representation, (2) combination of MFCC with Delta coefficients, and (3) combination of MFCC with Delta and Delta–Delta coefficients. The implemented model is evaluated using different test sets of varying sizes of 100, 200, 500, 1000, 1500, and 2000. Evaluation is performed for both noised and noiseless speech using these three feature representation models and performed an evaluation of these three models. For evaluating this model’s performance in noised conditions, both white and babble noises of various signal-to-noise ratio values such as 10 dB, 20 dB, and 30 dB are added into the noiseless speech and estimate the classification accuracy in those situations. The proposed KNN–DTW model with MFCC outperformed all the other models in the literature. MFCC with Delta and Delta–Delta coefficients is effective than other two models using MFCC and MFCC with Delta coefficients. The proposed model could be used to recognize the isolated word recognition of grade 1 textbook vocabulary in classroom noisy environment for providing a better interactive classroom environment to Kuwaiti elementary students to enhance their math learning level. In an interactive computer-based education environment for Mathematics learning, the proposed model could be recognized as the spoken utterances of students.
Full-Reference Objective Quality Metric for Three-Dimensional Deformed Models
Authors: Elloumi Nessrine , Loukil Habiba , Bouhlel Med Salim
Published: September 2022

Three-dimensional data are generally represented by triangular meshes. The 3D data are used in several fields including remote 3D games, 3D medical application, 3D virtual worlds and 3D augmented reality application. These applications require displaying, printing or exchanging the 3D models through the network to optimize the rendering of the 3D models and 3D applications, which include different treatments, for example, smoothing, compression, re-meshing, simplification, watermarking, etc. However, these processes generate distortions that affect the quality of the rendered 3D data. Thus, subjective or objective metrics are required for assessing the visual quality of the deformed models to evaluate the efficiency of the applied algorithms. In this context, we introduce a new perceptual full-reference metric that compare two 3D meshes based on their 3D content information. The proposed metric integrates the relativity and selectivity properties of the Human visual system (HVS) independent of the mesh type and connectivity (e.g. Triangular, Quadrilateral, Tetrahedron, Hexahedron), which represent a limit in the existing method, in order to capture the perceptual quantity of the distortion by the observer. The results of the proposed approach outperform the existing metrics and have a high correlation with the subjective measures. We use the two correlation coefficients Spearman Rank ([Formula: see text]) and Pearson Rank (Rp) in order to assess the performance of the proposed metric.
Climate Change and India: Balancing Domestic and International Interests
Authors: MITRA SUBRATA K. , PAULI MARKUS , SCHOTTLI JIVANTA
Published: September 2022

In this paper, we analyze how India’s climate change policy is framed, formulated and implemented and argue that it requires carefully balancing of domestic and international interests. Given the country’s population size, composition and projected economic growth, India will, in the next few years, see its most significant energy demand upsurge along with a massive need for infrastructure. As projected by the International Energy Agency, “nearly 60% of its CO2 emissions in the late 2030s will be coming from infrastructure and machines that do not exist today”. As a result, policy choices made today by India’s decision-makers and international negotiators will have severe implications for the world.

This paper analyzes global emission trends, climate change impacts and India’s international and domestic climate policies—from Paris to Glasgow and New Delhi to rural India. Furthermore, we examine the core constraints that Indian policymakers face and draw attention to shortcomings in India’s climate change policies, particularly concerning continued investment in coal despite the country’s widely lauded efforts to embrace renewables. We argue that fossil fuel subsidies are a delicate political issue with significant implications for many election-determining poor citizens—hence accompanying “just transition” measures are essential.
Loppa High Composite Tectono-Sedimentary Element, Barents Sea
Authors: Brunstad Harald , Rønnevik Hans Christen
Published: September 2022

The Loppa High Composite Tectono-Sedimentary Element is a mature exploration area in the southwestern Norwegian Barents Sea hosting Skrugard (in 2012) and the Late Paleozoic Gohta (in 2013) discoveries. The exploration of the Norwegian Barents Sea started in 1980 and the Loppa High in 1985. Today the Loppa High is one of the most studied areas of the Barents Shelf. Subsurface mapping is based on dense coverage of modern 3D and 2D seismic data and drilling results of over 40 exploration wells. This chapter summarizes the tectonosedimentary and subregional development, and the petroleum geology of the Loppa High.
Myocardial Infarction with Nonobstructive Coronary Arteries
Authors: Reynolds H.R. , Smilowitz N.R.
Published: September 2022

Myocardial infarction with nonobstructive coronary arteries (MINOCA) is an important subtype of myocardial infarction (MI) that occurs in approximately 6–8% of patients with spontaneous MI who are referred for coronary angiography. MINOCA disproportionately affects women, but men are also affected. Pathogenesis is more variable than in MI with obstructive coronary artery disease (MI-CAD). Dominant mechanisms include atherosclerosis, thrombosis, and coronary artery spasm. Management of MINOCA varies based on the underlying mechanism of infarction. Therefore, systematic approaches to diagnosis are recommended. The combination of invasive coronary angiography, multivessel intracoronary imaging, provocative testing for coronary spasm, and cardiac magnetic resonance imaging provides the greatest diagnostic yield. Current clinical practice guidelines for the secondary prevention of MI are based largely on data from patients with MI-CAD. Thus, optimal medications after MINOCA are uncertain. Clinical trials focused on the treatment of patients with MINOCA are urgently needed to define optimal care.
(Invited, Digital Presentation) Carbon-Based Multi-Porous-Layered-Electrodes for Highly-Stable Perovskite Solar Cells for Space Application
Authors: Ito Seigo , Sakai Youichirou , Tsuji Ryuki , Shioki Takaya
Published: September 2022

Organo-lead halide perovskite solar cells (PSCs) have attracted the attention due to the high efficiency and the cost-effective manufacturing by printing system. However, PSCs have been unstable due to water from outside and iodide (I-) reacts with the back contact metal (Au or Ag) inside. To solve these two issues, porous-carbon-electrodes have been introduced in PSCs. We are showing a challenging work of high thermal stability at 100-140 ֩C in vacuum, which is required for outer space application.
(Invited) Material Porosity
Authors: O'Dwyer Colm
Published: September 2022

Big pores, small pores, ordered pores, random pores – they all have a function and as is often found, show behaviour in new materials that is not always predicted or obvious at the outset. I started my research journey trying to put extremely thin films onto near-perfect III-V crystals to control (opto)electronic properties and when the first TEM on our campus showed remarkable pore growth and structure in InP almost 21 years ago, the electrochemical modification of the InP made more sense. In this paper, I will summarise a few aspects of research into porous materials and semiconductors, from porous InP that led to studies of other porous semiconductors such as silicon, GaN, ZnO and Indium Tin oxide (ITO), to periodically ordered photonic crystal porous structures and some optical, thermal and electrochemical properties, photocatalysis, studies in batteries and related that were enabled or modified by the porous structure.
(Invited) Single Photon Detectors and Metrology
Authors: Buckley Sonia Mary , Stephens M , Lehman J.H.
Published: September 2022

For quantum applications, it is important to generate quantum states of light and detect them with extremely high efficiency. For future applications, it also important to do this at scale. This presents many engineering and metrology challenges. This paper discusses some of the open challenges and opportunities in single photon detector efficiency measurements, including the challenges ofmetrology for waveguide-integrated detectors on photonic circuits.
Reduced Pressure – Chemical Vapor Deposition of Monocrystalline and Polycrystalline Si(:B) and SiGe(:B) Layers on Blanket Wafers
Authors: Lespiaux Justine , Deprat Fabien , Vives Jérémy , Duru Romain , Bicer Mehmet , Gauthier Alexis , Brezza Edoardo , Juhel Marc , Chenevas-Paule Florence , Baron Alain , Valery Alexia , Hartmann Jean-Michel
Published: September 2022

In this paper, epitaxial growths or depositions were performed, in 300 mm RP-CVD chambers, on two types of templates: N-type Si substrates or poly-Si/oxide/ P-type Si substrates. SiH4+HCl+H2 and SiH2Cl2+HCl+GeH4+H2 chemistries were used to deposit Si and SiGe layers between 675-750°C and 10-20 Torr on such wafers. Monocrystalline and polycrystalline growth kinetics were similar for intrinsic SiGe. Meanwhile, growth kinetics and boron incorporation were different for mono-Si:B, mono-SiGe:B, poly-Si:B and poly-SiGe:B layers. While the impact of B atoms is well documented in monocrystalline layers, it is still poorly understood for polycrystalline layers. An attempt has therefore been made to quantify it by measuring the poly-structure, with a focus on the poly-grains size and the number of grain boundaries. A lattice contraction coefficient β = - 9.82 * 10-24 cm3 has otherwise been extracted from an in-depth study of the incorporation of B atoms into substitutional sites of the SiGe epitaxial lattice.