bluuebunny/crossref_metadata_2025 huggingface dataset:
A Reduced-Order Multi-Body Model for Ornithopters With Piezocomposite Flapping Wings
Authors: Shan Xin , Bilgen Onur
Published: November 2022

Mechanism-free ornithopters, also referred to as solid-state ornithopters, based on piezoelectric actuators do not need electromagnetic motors or conventional mechanisms, potentially saving weight and energy consumption, and reducing mechanical complexity. In such vehicles, the aim is to achieve lift and thrust purely by surface-mounted piezoelectric actuators; however, the generating sufficient lift and thrust without mechanism augmentation is extremely difficult; and has not been demonstrated. The optimization of wing substrate topology, actuator placement, and excitation parameters requires a computationally efficient model of the dynamic behavior of a solid-state ornithopter. In this article, a reduced-order lumped-parameter model is proposed for ornithopters with piezocomposite flapping wings. The piezoelectric, mechanical, and fluid domains are modeled and coupled by Hamilton’s principle. Based on the Rayleigh-Ritz method, the wing motion is described by the assumed bending and twisting modes to predict plunging and pitching motions. The fluid effects considered are added mass and quasi-static aerodynamic forces. A vortex lattice code is used to obtain aerodynamic coefficients for the wing. The body-wing and the wing-fluid interactions are accounted for in the model. Gliding flapping flight simulations with initial velocity and height are conducted. Contribution of active flapping are found by comparison to flight with non-flapping compliant wings.
Experimental Validation For A Multi-Objective Optimized Piezocomposite Morphing Airfoil
Authors: Wright Cody , Bilgen Onur
Published: November 2022

Slotted natural-laminar-flow airfoils are multi-element airfoils that employ a slot between the fore and aft elements to improve aerodynamic efficiency at cruise. Flow on the fore element pressure surface accelerates the flow through the slot which in-turn provides a pressure recovery mechanism for the suction surface of the fore element. This synergy delays the laminar to turbulent transition of the fore element leading to improved lift and a reduction in drag. These aerodynamic benefits permit aircraft designs with smaller planforms, reducing fuel burn. Smooth continuous surfaces are necessary to maintain proper flow on both the fore and aft element. For this reason, deployable surfaces to increase lift such as traditionally actuated flaps and slats can lead to premature tripping of the laminar to turbulent transition. To prevent this unwanted behavior, it is proposed that piezocomposite or other smart-material actuators are used for camber morphing of the aft element to modify lift. To this end, a parameterized model is proposed for piezocomposite airfoil morphing. The model is then applied to the aft element of a slotted natural-laminar flow airfoil with the fore element assumed as a rigid structure. A fluid-structure interaction framework is employed for determining the deformed actuated airfoil geometry subject to aerodynamic loading. Finally, a multi-objective optimization algorithm is used to generate the pareto front of two competing objective functions, maximizing excited airfoil lift and minimizing unexcited pressure induced deformation of the airfoil.
Adaptive Magneto-Responsive Surfaces Fabricated by Laser-Based Microstructuring
Authors: Kravanja Gaia , Belyaeva Inna A. , Hribar Luka , Drevenšek-Olenik Irena , Shamonin Mikhail , Jezeršek Matija
Published: November 2022

Adaptive surface microstructures are used extensively in nature to control various surface properties such as wettability, adhesion, self-cleaning, drag reduction, etc. Regulation of these properties can be achieved with the appropriate employment of a multitude of smart materials, whose characteristics/response can be controlled by noncontact stimuli, e.g., light, heat, or magnetic field. One of the very promising magneto-regulable smart materials are magnetoactive elastomers (MAEs). They are comprised of a compliant polymer matrix with embedded micrometer-sized ferromagnetic particles. The particles interact with each other and a magnetic field. This results in remarkable tunability of the physical properties of MAEs. This paper reports a fast, resilient, and tailored method for direct surface micromachining of MAEs that enables micro-structuring without mechanical contact between the tool and the material, bypassing the usual constraints of conventional fabrication methods. It is shown that it is possible to fabricate a large variety of different microstructure geometries whose precision is limited predominantly by the size of magnetic particles. Lamellar structures with a high aspect ratio (up to 6:1) oriented either perpendicularly to the surface, can be strongly bent by applying magnetic fields in the range of 0–250 mT.
Examination of the Interdependency of Applied Load, Realizable Stroke and Transition Temperatures in Cyclic Tests Concerning Lifetime of Single Crystalline CuAlNi
Authors: Langhoff Moritz , Horn Simon , Krieg Romina , Krancher Christian , Hoffmann Fabian , Theiß Ralf , Dültgen Peter
Published: November 2022

Copper-based shape memory alloys (Cu-SMA) are known for their high transition temperatures and therefore their potential for actuation applications in environments with higher temperatures than tolerable for binary NiTi. Due to the higher transition temperatures of Cu-SMA cooling rates are higher, so technical applications could work with higher dynamics. A huge disadvantage is the low durability in the lifecycle of actuation compared to NiTi-SMA. As already known, there are many factors influencing the lifetime of SMA-elements, such as applied load, stroke, and the element’s temperature during activation. Besides the SMA’s typical degradation of strain, the transition temperatures of CuAlNi are influenced under high actuation temperatures and stresses, so that they are constantly shifting over the lifetime. This behavior is not tolerable for industrial applications since it makes the designing of the actuators highly demanding and high ranges for the attainable stroke must be considered for the dimensioning process. To overcome these problems a deeper understanding of the dependencies of the values such as stroke and the activation temperature on the cycle number is necessary. In this study, the effects of electrical cyclic heating of single crystalline CuAlNi SMA wires were investigated to analyze influencing factors on the life cycle behavior. Therefore, samples were loaded with constant stresses varying from 80–200 MPa in four steps. Various actuation temperatures were applied to the specimen, from “overheated” to slightly above Af and temperatures relating to partly activated (about 50% austenite).
Fabrication of 3D Printed Thermoelectric Devices for Integration Into Liquid Crystal Elastomer Actuators
Authors: Zadan Mason , Patel Dinesh K. , Malakooti Mohammad H. , Yao Lining , Majidi Carmel
Published: November 2022

Shape memory materials such as liquid crystal elastomers (LCE) have been explored as soft robotic actuators due to their high mechanical robustness and muscle-like work densities. The main drawback of LCEs is slow response times and low energy efficiencies stemming from poor thermal management. Thermoelectric devices (TED), which generate temperatures differentials across semiconductors through the Peltier effect when current is applied, have the potential to address these long response times. By introducing additive manufacturing along with conductive liquid metal (LM) traces, we introduce TED for soft robotic applications. In this study, we build on recent work in soft thermoelectric generators to create high density arrays of thermoelectric semiconductors to actively heat and cool LCEs. We describe advancements in the manufacturing of a soft TED in which we achieve a 28% fill factor of semiconductors through the use of 3D printing. We report maximum power densities of 236 μWcm−2 at ΔT = 60 °C. By coating LCE on each side of the TED we create single input multidirectional liquid crystal elastomer thermoelectric device (LCE-TED) actuators. Thermal management design challenges are discussed along with the introduction of liquid metal embedded elastomer composites (LMEE) into TED design. Lastly, we introduce an inchworm inspired soft robot walker based on these LCE-TED actuators. We highlight gait mechanics for three cycles of actuation for this soft robotic system.
Effect of Multilayer Dielectric Elastomer Actuator (DEA) Construction on Performance and Breakdown Strength
Authors: Masud Md Abdulla Al , Hines Lindsey , Ng Chin-Yee , Hu Jia
Published: November 2022

Dielectric elastomer actuators (DEAs), unlike traditional actuators, are lightweight, soft, smart materials that are proving to be attractive in a broad range of potential applications such as robotic arms, artificial muscles, medical devices, stretchable sensors, grippers, loudspeakers, and automotive lightweighting. Though they have been known and studied for decades, their use is not widespead in part due to a number of practical implementation difficulties including the need for and handling of thin dielectric layers to reduce operating voltage, strechable and stackable electrodes that don’t overly degrade performance, and poor longevity due to electrical breakdown contributed by potential flaws in the thin film and material inclusions/irregularities. This paper investigates the construction of DEA multi-layer and single-layer articles, exploring the effect of non-negligible elastomer-based electrodes with various dielectric/electrode layer thickness ratios as well as the influence of stacked dielectric layers on breakdown voltage. A balance between actuator performance and the level of required voltage for operation is shown given a set of assumptions. Furthermore, the influence of stacked dielectric layers on breakdown voltage is demonstrated, confirming previous results performed with polyvinylidene fluoride (PVDF).
Electrical Conductivity of Multifunctional Blend Composites of Polycarbonate and Polyethylene With Hybrid Fillers
Authors: Naji Ahmed , Pötschke Petra , Ameli Amir
Published: November 2022

Multifunctional composites are in high demand where a material needs to simultaneously satisfy several functional requirements. Bipolar plates of polymer electrolyte membrane fuel cells are great examples of this kind, requiring very high electrical and thermal conductivities together with good mechanical properties and environmental durability. Conductive filler/polymer composites (CPCs) have shown some promise towards this application. However, achieving high levels of through-plane and in-plane electrical conductivities in CPCs while maintaining scalable processability and satisfactory level of mechanical performance is challenging. In this work, a polymeric blend system together with hybrid conductive fillers was designed, manufactured, and characterized in an attempt to obtain melt-processable, highly conductive composites. Polycarbonate (PC) and high-density polyethylene (HDPE) were employed as the blend matrix with polyethylene glycol (PEG) as the compatibilizer. Carbon nanotubes (CNT), carbon fibers (CF), and graphite (G) were utilized as the conductive fillers. The HDPE was used as the minor component of blend matrix at 30 wt.% of the major matrix PC, with PC having the better affinity to the fillers. This was done to localize the conductive fillers in the major PC component of the blend. CF and G were used in ranges of 10–30 wt. % and 30–50 wt. % of the composites, respectively. CNT and PEG were fixed at 3 wt. % and 1.5 wt. %, respectively. The composites were first compounded using a twin-screw extrusion system and the test specimens were then made using compression molding process. The results showed that due to the preferential localization of the fillers in PC component of the PC/HDPE blend, the electrical conductivities were increased by about three times, compared to that of CPCs made with PC-only matrix. Consequently, high through-plane and in-plane conductivities of 10.0 and 61.1 S/cm, respectively, were achieved, which are superior to most of the previously reported results. The findings suggest that integrating blending and hybrid filler strategies could be a promising approach towards scalable manufacturing of highly conductive CPCs for applications such as bipolar plates.
Investigations into acoustic dipole helical wave generation
Authors: Eastland Grant C. , Curry Peter J. , Tolliver Laura C.
Published: November 2022

Acoustic waves that transmit phase information spatially have recently been applied to navigation and communications systems. This paper will describe a helical wave, a type of wave that transmits phase information across a section of the plane linearly about the azimuth. The wave will be described from the ground up. First, a circular baffled transducer pressure field will be derived. Next, the field generated using two crossed circular transducers will be derived and approximations given for the far field. The general expression for the acoustic field from this arrangement is derived in the far field utilizing a paraxial ray approximation for ideal sources but applied to the more complex conceptualization of the monopole source being given by the circular piston source. In addition, the work presented was investigated numerically in comparison to a different approximation made in the field dependence on monopole separation of the two sources making up the dipole. Next, numerical examination of two crossed dipoles is examined with visualizations of the pressure and discussion of transients created when the direction of spiral changes. Finally, there is a discussion for the detection and estimation of helical waves and potential uses.
ERG11
Analysis among Clinical Isolates of Trichosporon asahii with Different Azole Susceptibility Profiles
Authors: Nobrega de Almeida João , Jimenez-Ortigosa Cristina , Francisco Elaine Cristina , Colombo Arnaldo L. , Perlin David S.
Published: November 2022

We analyzed a cohort of
Trichosporon asahii
strains with different MICs of fluconazole and voriconazole and evaluated the presence of
ERG11
mutations.
ERG11
mutation conferring an amino acid change was found and its resistance potential was evaluated by cloning into
Saccharomyces cerevisiae
susceptible host strain. Transformants were not resistant to either fluconazole nor voriconazole.
Feline Leukemia Virus Frequently Spills Over from Domestic Cats to North American Pumas
Authors: Petch Raegan J. , Gagne Roderick B. , Chiu Elliott , Mankowski Clara , Rudd Jaime , Roelke-Parker Melody , Vickers T. Winston , Logan Kenneth A. , Alldredge Mathew , Clifford Deana , Cunningham Mark W. , Onorato Dave , VandeWoude Sue
Published: November 2022

Feline leukemia virus (FeLV) is a retrovirus that primarily affects domestic cats. Close interactions with domestic cats, including predation, can lead to the interspecific transmission of the virus to pumas, bobcats, or other feline species.
Type IV Pili Are a Critical Virulence Factor in Clinical Isolates of Paenibacillus thiaminolyticus
Authors: Hehnly Christine , Shi Aiqin , Ssentongo Paddy , Zhang Lijun , Isaacs Albert , Morton Sarah U. , Streck Nicholas , Erdmann-Gilmore Petra , Tolstoy Igor , Townsend R. Reid , Limbrick David D. , Paulson Joseph N. , Ericson Jessica E. , Galperin Michael Y. , Schiff Steven J. , Broach James R.
Published: November 2022

Postinfectious hydrocephalus, a devastating sequela of neonatal infection, is associated with increased childhood mortality and morbidity. A novel bacterial pathogen,
Paenibacillus thiaminolyticus
, is highly associated with postinfectious hydrocephalus in an African cohort.
Draft Genome Sequence of Candida railenensis Strain CLIB 1423, Isolated from Papaya Fruit in French Guiana
Authors: Devillers Hugo , Grondin Cécile , Thiriet Angèle , Legras Jean-Luc
Published: November 2022

Here, we report the draft genome sequence and annotation of the yeast
Candida railenensis
strain CLIB 1423. The assembly consists of 57 nuclear scaffolds and 1 complete mitochondrial chromosome, for a total of 13.8 Mb (
N
50
, 0.54 Mb;
L
50
, 9). The annotation contains 6,013 coding DNA sequences (CDSs) (BUSCO completeness, 99.6%).
Complete Genome Sequence of
Erythrobacter
sp. Strain SDW2, a Marine Bacterium Producing a Yellow Xanthophyll Pigment
Authors: Jeong Sun-Wook , Choi Yong Jun
Published: November 2022

Erythrobacter
sp. strain SDW2, which is capable of biosynthesizing a yellow xanthophyll pigment, was isolated from coastal seawater. Here, we report the complete genome sequence of this marine bacterial strain, with a genome size of 2,920,893 bp (64.38% G+C content) and 2,859 genes.
Ancestral APOBEC3B Nuclear Localization Is Maintained in Humans and Apes and Altered in Most Other Old World Primate Species
Authors: Auerbach Ashley A. , Becker Jordan T. , Moraes Sofia N. , Moghadasi Seyed Arad , Duda Jolene M. , Salamango Daniel J. , Harris Reuben S.
Published: November 2022

APOBEC3 enzymes are single-stranded DNA cytosine-to-uracil deaminases with beneficial roles in antiviral immunity and detrimental roles in cancer mutagenesis. Regarding viral infection, all seven human APOBEC3 enzymes have overlapping roles in restricting virus types that require DNA for replication, including EBV, HIV, human papillomavirus (HPV), and human T-cell leukemia virus (HTLV).
Epidemiology and Molecular Characteristics of
mcr-9
in
Citrobacter
spp. from Healthy Individuals and Patients in China
Authors: Ju Xiaoyang , Wang Siheng , Yang Xuemei , Han Weihua , Cai Chang , Wu Yuchen , Liu Congcong , Qian Jiao , Zhao Xiaofei , Qian Xiang , Sun Qiaoling , Zhang Rong , Chen Gongxiang
Published: November 2022

The emergence of
mcr
homologues posed a serious threat to the therapeutic efficiency of polymyxin antibiotics.
Citrobacter freundii
is generally regarded as an opportunistic pathogen associated with a variety of nosocomial infections. In this study, we investigated the prevalence of
mcr-9
in
Citrobacter
spp. isolates from healthy individuals and infected patients and highlighted the importance of the rational use of antibiotics.
Platelet Activation and Aggregation Induced by Streptococcus bovis
/
Streptococcus equinus Complex
Authors: Pernow Gustav , Shannon Oonagh , Öberg Jonas , Nilson Bo , Rasmussen Magnus
Published: November 2022

The capacity of bacteria to activate and aggregate platelets is believed to contribute to the pathogenesis of IE. The
Streptococcus bovis
/
Streptococcus equinus
complex (SBSEC) contains known IE-pathogens, but there is limited research on the different subspecies ability to interact with platelets and what signaling pathways are involved.
Novel Plasmid Carrying Mobile Colistin Resistance Gene
mcr-4.3
and Mercury Resistance Genes in Shewanella baltica: Insights into Mobilization of
mcr-4.3
in
Shewanella
Species
Authors: Marathe Nachiket P. , Salvà-Serra Francisco , Nimje Priyank S. , Moore Edward R. B.
Published: November 2022

We identified two new plasmids in
Shewanella baltica
isolated from wild Atlantic mackerel (
Scomber scombrus
) collected from the northern North Sea, one plasmid carrying the
mcr-4.3
gene for colistin resistance and the operon
merRPAT
for mercury resistance and the other carrying multiple heavy metal resistance genes. The marine environment has been recognized as a source of new resistance genes that are found in human pathogens.
Comparative Analysis of Phylogenetic Relationships and Virulence Factor Characteristics between Extended-Spectrum β-Lactamase-Producing Escherichia coli Isolates Derived from Clinical Sites and Chicken Farms
Authors: Li Chao , Chen Xuan , Ju Zijing , Li Cui , Xu Ying , Ding Jiawei , Wang Yuting , Ma Peng , Gu Kui , Lei Changwei , Tang Yizhi , Wang Hongning
Published: November 2022

Bacterial drug resistance has become one of the most significant threats to human health worldwide, especially for extended-spectrum β-lactamase-producing
E. coli
(ESBL-
E. coli
). Timely and accurate epidemiological surveys can provide scientific guidance for the adoption of treatments in different regions and also reduce the formation of drug-resistant bacteria.
Distinct Long- and Short-Term Adaptive Mechanisms in Pseudomonas aeruginosa
Authors: Koska Michal , Kordes Adrian , Erdmann Jelena , Willger Sven D. , Thöming Janne G. , Bähre Heike , Häussler Susanne
Published: November 2022

Extreme environments, such as those encountered during an infection process in the human host, make effective bacterial adaptation inevitable. While bacteria adapt individually by activating stress responses, long-term adaptation of bacterial communities to challenging conditions can be achieved via genetic fixation of favorable traits.
The autonomy of public health facilities in decentralised contexts: insights from applying a complexity lens in Kenya
Authors: Barasa Edwine , Nyawira Lizah , Musiega Anita , Kairu Angela , Orangi Stacey , Tsofa Benjamin
Published: November 2022

The financing of public health facilities influences their performance. A key feature that defines health facility financing is the degree of financial autonomy. Understanding the factors that influence public health facility financial autonomy is pertinent to developing strategies to addressing challenges that arise from constrained autonomy. In this paper, we apply a complexity lens to draw on a body of research that we have conducted in Kenya over the past decade, from the onset of devolution reforms, to unpack the determinants of public health facility financial autonomy in a context of decentralisation and provide suggestions for pertinent considerations when designing interventions to address financial autonomy challenges. We find that the factors that affect public health facility autonomy are not only structural, but also procedural, and political and interact in complex ways. These factors include; the public finance management (PFM) laws, sense-making by actors in the health system, political interests in control over resources, subnational level PFM capacity, PFM implementation bottlenecks and broader operational autonomy. Drawing from this analysis, we recommend that efforts at resolving public health facility financial autonomy include: PFM capacity development for subnational levels of government in decentralised settings, the use of a political lens that recognises interests and seeks to align incentives in engagement and solution finding for health facility financial autonomy, the audit of PFM processes to establish and resolve implementation bottlenecks that impinge on public health facility autonomy, and the resolution of operational autonomy to as a facilitator of financial autonomy.
Perceived discharge quality and associations with hospital readmissions and emergency department use: a prospective cohort study
Authors: Perera Tefani , Grewal Eshleen , Ghali William A , Tang Karen L
Published: November 2022

Background

At hospital discharge, care is handed over from providers to patients. Discharge encounters must prepare patients to self-manage their health, but have been found to be suboptimal. Our study objectives were to describe and determine the correlates of perceived discharge quality and to explore the association between perceived discharge quality and postdischarge outcomes.

Methods

We conducted a prospective cohort study in medical inpatients admitted to a tertiary care hospital in Calgary, Canada. Perceived discharge quality was measured by the Care Transitions Measure (CTM). Linkage to administrative databases provided data for the composite outcome—90-day hospital readmission or emergency department visit. Logistic regression modelling was used to determine the association between global CTM scores, and the individual CTM components, and the composite outcome.

Results

A total of 316 patients were included in the analysis. The median CTM score was 80.0 (IQR 66.6–100.0). The distribution of CTM scores were significantly different based on comorbidity burden, with the median and maximum CTM scores being lower and the IQR being narrower, for those with six or more comorbidities compared with those with fewer comorbidities. CTM scores were not associated with the composite outcome, though a single CTM item—not understanding warning signs and symptoms—was (adjusted OR 3.46 (95% CI 1.02 to 11.73)).

Conclusion

Perceived quality of discharge varies based on patient burden of comorbidities. While global perceived discharge quality was not associated with postdischarge outcomes, lack of patient understanding of warning symptoms was. Discharging healthcare teams should pay special attention to these priority patient groups and specific discharge process components.
Advancing the Real-World Evidence for Medical Devices through Coordinated Registry Networks
Authors: Sedrakyan Art , Marinac-Dabic Danica , Campbell Bruce , Aryal Suvekshya , Baird Courtney E , Goodney Philip , Cronenwett Jack L , Beck Adam W , Paxton Elizabeth W , Hu Jim , Brindis Ralph , Baskin Kevin , Cowley Terrie , Levy Jeffery , Liebeskind David S , Poulose Benjamin K , Rardin Charles R , Resnic Frederic S , Tcheng James , Fisher Benjamin , Viviano Charles , Devlin Vincent , Sheldon Murray , Eldrup-Jorgensen Jens , Berlin Jesse A , Drozda Joseph , Matheny Michael E , Dhruva Sanket S , Feeney Timothy , Mitchell Kristi , Pappas Gregory
Published: November 2022

Objectives

Generating and using real-world evidence (RWE) is a pragmatic solution for evaluating health technologies. RWE is recognized by regulators, health technology assessors, clinicians, and manufacturers as a valid source of information to support their decision-making. Well-designed registries can provide RWE and become more powerful when linked with electronic health records and administrative databases in coordinated registry networks (CRNs). Our objective was to create a framework of maturity of CRNs and registries, so guiding their development and the prioritization of funding.

Design, setting, and participants

We invited 52 stakeholders from diverse backgrounds including patient advocacy groups, academic, clinical, industry and regulatory experts to participate on a Delphi survey. Of those invited, 42 participated in the survey to provide feedback on the maturity framework for CRNs and registries. An expert panel reviewed the responses to refine the framework until the target consensus of 80% was reached. Two rounds of the Delphi were distributed via Qualtrics online platform from July to August 2020 and from October to November 2020.

Main outcome measures

Consensus on the maturity framework for CRNs and registries consisted of seven domains (unique device identification, efficient data collection, data quality, product life cycle approach, governance and sustainability, quality improvement, and patient-reported outcomes), each presented with five levels of maturity.

Results

Of 52 invited experts, 41 (79.9%) responded to round 1; all 41 responded to round 2; and consensus was reached for most domains. The expert panel resolved the disagreements and final consensus estimates ranged from 80.5% to 92.7% for seven domains.

Conclusions

We have developed a robust framework to assess the maturity of any CRN (or registry) to provide reliable RWE. This framework will promote harmonization of approaches to RWE generation across different disciplines and health systems. The domains and their levels may evolve over time as new solutions become available.
Dynamics of tachyonic dark matter
Authors: Starke James M. , Redmount Ian H.
Published: November 2022

Usually considered highly speculative, tachyons can be treated via straightforward Einsteinian dynamics. Kinetic theory and thermodynamics for a gas of “dark” tachyons are readily constructed. Such a gas exhibits density and pressure which, for the dominant constituent of a suitable Friedmann–Robertson–Walker space–time, can drive cosmic evolution with features both similar to and distinct from those of a standard dark-energy/dark-matter model. Hence, tachyons might bear further consideration as a cosmic dark-matter candidate.
Feature Extraction and Pattern Recognition Algorithm of Power Cable Partial Discharge Signal
Authors: Du Jie , Mi Jianwei , Jia Zhanpeng , Mei Jiaxiang
Published: November 2022

The degree of insulation aging of power cables is closely related to their partial discharge (PD) level, so the analysis of PD signals can be used to realize the cable condition detection. However, after performing online detection of PDs on power cables, the collected signals always contain interference signals due to the influence of electromagnetic interference in the field. In order to identify each type of local discharge signal from the interference signal, this paper proposes a clustering identification algorithm for local discharge signals, which mainly involves pulse extraction, feature parameter extraction and clustering identification process. The algorithm first extracts the pulse signal by combining the amplitude–time threshold method and the time domain energy method, then obtains the feature vector of the signal according to the synchronous multi-channel method, designs a fuzzy C-mean clustering algorithm based on subtractive clustering to determine the initial clustering center to cluster the samples and finally analyzes and checks the clustering results according to the phase resolved PD (PRPD) of a single class of signals and the fit of the two-parameter Weibull distribution function. The clustering results were analyzed and examined. The experimental results show that the proposed algorithm can extract pulse signals efficiently and accurately, and the synchronous multi-channel method can characterize pulse signals better. Meanwhile, the algorithm can determine the optimal number of classes adaptively according to the clustering effectiveness function and adopt subtractive clustering to initialize the clustering center, which can approach the optimal solution faster, and can effectively cluster a variety of discharge signals, so as to realize the type identification of single-class discharge signals.
Matching Logic for Concurrent Programs Based on Rely/Guarantee and Abstract Patterns
Authors: Wang ShangBei , Dong WeiYu
Published: November 2022

This paper combines rely/guarantee, abstract patterns and matching logic to reason about concurrent programs in a modular and compositional manner. According to the separation property, the state can be divided into two disjoint parts, the local state and the shared state. We use matching logic to deal with the local state, and use rely/guarantee and abstract patterns to deal with the shared state. The power of rely/guarantee is to describe interference between concurrent programs. The advantage of abstract patterns is supporting fictional separation, which indicates that we logically consider abstract patterns to represent disjoint elements, although these elements are not disjoint under a certain implementation. By combining the advantages of rely/guarantee, abstract patterns and matching logic, our approach realize that clients of the module can be verified completely according to the specification of the module, regardless of the implementation of the module. In addition, we use several examples to illustrate our approach, define our logic judgments, and prove the soundness of our logic.
Multiple-component spectral analysis of 24 Fermi LAT GRBs and the Eiso-Ei,peak relation
Authors: Zafar Hira , Sajjad Saeeda , Motiwala Khadeejah
Published: November 2022

The use of correlations between various observable quantities for Gamma-ray bursts (GRBs) has been the subject of much interest and discussion. In particular, many studies have explored the Eiso-Ei,peak relation, its origin and its potential use as a means to discriminate between GRBs from various progenitors. Observations of GRBs through the Fermi Gamma-Ray Space Telescope have also opened up the possibility of studying this correlation over a wide range of energies from keVs to GeVs. While the correlation has been studied through Fermi Large Area Telescope (LAT) GRBs with measured redshifts, its compatibility with LAT GRBs without measured redshifts is yet to be tested. In this paper, we study this correlation with a sample of 24 Fermi LAT GRBs with unknown redshift. We analyze their data between 8 keV and 100 GeV through single and multiple-component spectral models. We use the results of this analysis to study the compatibility of these GRBs with the Eiso-Ei,peak relation by varying the redshift continuously between 0.3 and 10.5. We find that all 24 GRBs are compatible with the Eiso-Ei,peak relation within a 1-sigma uncertainty for a certain redshift range. The range of compatible redshifts found for each GRB remains consistent with observed redshifts for long GRBs.
On the rate of convergence of weighted oscillating ergodic averages
Authors: Darwiche Ahmad , Schneider Dominique
Published: November 2022

Let [Formula: see text] be a probability space, let [Formula: see text] be a contraction on [Formula: see text] and let [Formula: see text] in [Formula: see text], ([Formula: see text]). In this paper, we provide suitable conditions over sequences [Formula: see text], [Formula: see text] and [Formula: see text] in such a way that the limit of the weighted ergodic average is [Formula: see text] [Formula: see text]-a.e. We also give applications which concretely prove the effectiveness of the obtained theorems. More precisely, we construct sequences [Formula: see text] and [Formula: see text] that were difficult to deal with previously, which satisfy the conditions of our theorems.
An Experimental Study on Evaluating Alzheimer’s Disease Features using Data Mining Techniques
Authors: Albalawi Hadeel
Published: November 2022

Alzheimer’s disease (AD) predominantly affects the elderly population with symptoms including, but not limited to, cognitive impairment and memory loss. Predicting AD and mild cognitive impairment (MCI) can lengthen the lifespan of patients and help them to access necessary medical resources. One potential approach to achieve an early diagnosis of AD is to use data mining techniques which explore various characteristic traits related to MCI, cognitively normal (CN), and AD subjects to build classifiers that reveal important contributors to the disease. These classifiers are used by physicians during the AD diagnostic process in a clinical evaluation. In this research, we compare between different data mining algorithms through empirical data approach to deal with the AD diagnosis. Experimental evaluation, using attribute selection methods, and classifiers from rule induction and other classification techniques have been conducted on data from the Alzheimer’s Disease Neuroimaging Initiative (ADNI-MERGE). The results illustrate the good classification performance of classifiers with rules in predicting AD.
Antibacterial Activities of Ethiopian Natural Honey Against Iron and Nickel-Doped ZnO Nanoparticles
Authors: Alemu Elias , Tegegne Newaymedhin Aberra , Lachore Wegene Lema , Garedew Asnake Desalegn , Dejene Francis Birhanu , Hone Fekadu Gashaw
Published: November 2022

In this work, the antibacterial activities of natural Ethiopian honey and iron (Fe)-/nickel (Ni)-doped ZnO nanoparticles against Gram-positive and Gram-negative bacteria were investigated. The test strains used were Staphylococcus aureus (S. aureus ATCC25923) and Escherichia coli (E. coli ATCC25922). The co-precipitation method was used to prepare Fe- and Ni-doped ZnO nanoparticles (NPs). The X-ray diffraction (XRD) study revealed that the prepared samples have hexagonal crystal structure with a preferred orientation along the (101) plane. The average crystal sizes for iron and nickel-doped NPs were 39.09[Formula: see text]nm and 34.30[Formula: see text]nm, respectively. The energy dispersive analysis of X-ray spectra (EDX) analyses confirmed the presence of Zn, O, Fe and Ni elements in the prepared NPs samples. A strong emission peak at 454[Formula: see text]nm was observed in the photoluminescence spectra of the NPs. In order to characterize the honey’s composition, variety of physico-chemical and optical approaches were used. The absorption spectra of the three samples of honey are comparable and exhibited a noticeable peak about 260[Formula: see text]nm. The FTIR analysis confirmed that the honey samples contained the expected functional groups. The agar well diffusion technique was used to investigate the antibacterial efficacy of Fe- and Ni-doped ZnO NPs as well as Ethiopian natural honey. The results show that against E. coli strains and S. aureus strains, respectively, Fe-doped and Ni-doped ZnO NPs had average inhibitory zones of 17.1[Formula: see text]mm, 15.7[Formula: see text]mm, 15.5[Formula: see text]mm and 14.7[Formula: see text]mm, respectively. Against the S. aureus strain, the natural honey displayed a maximal inhibition zone of 12.6[Formula: see text]mm and no inhibition zone at all for E. coli.
The Effect of Surface Morphology of Silver Nanoparticles on the Selectivity of Styrene Epoxidation
Authors: Sarıbıyık Oğuz Yunus
Published: November 2022

Catalytic materials at the nanoscale level have an enormous impact on sustainable environmental protection, which is important for the future. Therefore, the researchers will intensively carry out the design of catalytic materials with well-ordered surface structures. In more detail, morphology-controlled nanoparticles have special interactions with the reactants that increase catalytic performance and influence the selectivity for catalytic reactions. For those reasons, obtaining specifically surface structure-tuned nanocrystals having different surface arrangements is a significant priority that promises the best model relationship between well-oriented surface structure and catalytic performance. In this study, silver nanocrystals shaped with cubes, truncated octahedrons, and octahedrons were produced. Their catalytic behaviors were examined as an innovation for epoxidation/oxidation reactions of styrene in mild conditions. The morphological and surface characterizations of nanocrystals were determined by analytical and instrumental methods such as high-resolution transmission electron microscopy energy dispersive X-ray (HR-TEM-EDX), X-ray diffraction (XRD), as well as inductively coupled plasma mass spectroscopy optical emission spectrometry (ICP-OES), and gas chromatography-mass spectrometry (GC-MS). According to the results, nanoparticles having different surface-facets fractions can be employed to increase the selectivity of styrene epoxide.
Carbon Nanotubes (CNTs): Smart Theranostic Tools for the Recognition and Preclusion of SARS-COV-2 Variants
Authors: Garg Pankaj
Published: November 2022

The current review article explores the binding empathy of carbon nanotubes (CNTs) for different molecular targets, in the context of their potential use to fight against severe acute respiratory syndrome corona virus-2 (SARS-CoV-2). CNTs are touted as one of the most impending theranostic tools, owing to their exceptional mechanical, thermal and optical properties. Furthermore, their structural reliability and functional group flexibility make them especially useful for the design of advanced biosensing devices both for diagnostic and therapeutic applications against SARS-CoV-2. In addition, CNTs could also function both as an antigen carrier and an adjuvant when used concurrently with current and upcoming COVID-19 vaccines.
Re-locations: Augmenting Personal and Shared Workspaces to Support Remote Collaboration in Incongruent Spaces
Authors: Fink Daniel Immanuel , Zagermann Johannes , Reiterer Harald , Jetter Hans-Christian
Published: November 2022

Augmented reality (AR) can create the illusion of being virtually co-located during remote collaboration, e.g., by visualizing remote co-workers as avatars. However, spatial awareness of each other's activities is limited as physical spaces, including the position of physical devices, are often incongruent. Therefore, alignment methods are needed to support activities on physical devices. In this paper, we present the concept of Re-locations, a method for enabling remote collaboration with augmented reality in incongruent spaces. The idea of the concept is to enrich remote collaboration activities on multiple physical devices with attributes of co-located collaboration such as spatial awareness and spatial referencing by locally relocating remote user representations to user-defined workspaces. We evaluated the Re-locations concept in an explorative user study with dyads using an authentic, collaborative task. Our findings indicate that Re-locations introduce attributes of co-located collaboration like spatial awareness and social presence. Based on our findings, we provide implications for future research and design of remote collaboration systems using AR.
Leveraging Smartwatch and Earbuds Gesture Capture to Support Wearable Interaction
Authors: Rateau Hanae , Lank Edward , Liu Zhe
Published: November 2022

Due to the proliferation of smart wearables, it is now the case that designers can explore novel ways that devices can be used in combination by end-users. In this paper, we explore the gestural input enabled by the combination of smart earbuds coupled with a proximal smartwatch. We identify a consensus set of gestures and a taxonomy of the types of gestures participants create through an elicitation study. In a follow-on study conducted on Amazon's Mechanical Turk, we explore the social acceptability of gestures enabled by watch+earbud gesture capture. While elicited gestures continue to be simple, discrete, in-context actions, we find that elicited input is frequently abstract, varies in size and duration, and is split almost equally between on-body, proximal, and more distant actions. Together, our results provide guidelines for on-body, near-ear, and in-air input using earbuds and a smartwatch to support gesture capture.
Conductor: Intersection-Based Bimanual Pointing in Augmented and Virtual Reality
Authors: Zhang Futian , Katsuragawa Keiko , Lank Edward
Published: November 2022

Pointing is an elementary interaction in virtual and augmented reality environments, and, to effectively support selection, techniques must deal with the challenges of occlusion and depth specification. Most of the previous techniques require two explicit steps to handle occlusion. In this paper, we propose Conductor, an intuitive, plane-ray, intersection-based, 3D pointing technique where users leverage bimanual input to control a ray and intersecting plane. Conductor allows users to use the non-dominant hand to adjust the cursor distance on the ray while pointing with the dominant hand. We evaluate Conductor against Raycursor, a state-of-the-art VR pointing technique, and show that Conductor outperforms Raycursor for selection tasks. Given our results, we argue that bimanual selection techniques merit additional exploration to support object selection and placement within virtual environments.
HandyGaze: A Gaze Tracking Technique for Room-Scale Environments using a Single Smartphone
Authors: Nagai Takahiro , Fujita Kazuyuki , Takashima Kazuki , Kitamura Yoshifumi
Published: November 2022

We propose HandyGaze, a 6-DoF gaze tracking technique for room-scale environments that can be carried out by simply holding a smartphone naturally without installing any sensors or markers in the environment. Our technique simultaneously employs the smartphone’s front and rear cameras: The front camera estimates the user’s gaze vector relative to the smartphone, while the rear camera (and depth sensor, if available) performs self-localization by reconstructing a pre-obtained 3D map of the environment. To achieve this, we implemented a prototype that works on iOS smartphones by running an ARKit-based algorithm for estimating the user’s 6-DoF head orientation. We additionally implemented a novel calibration method that offsets the user-specific deviation between the head and gaze orientations. We then conducted a user study (N=10) that measured our technique’s positional accuracy to the gaze target under four conditions, based on combinations of use with and without a depth sensor and calibration. The results show that our calibration method was able to reduce the mean absolute error of the gaze point by 27%, with an error of 0.53 m when using the depth sensor. We also report the target size required to avoid erroneous inputs. Finally, we suggest possible applications such as a gaze-based guidance application for museums.
TetraForce: A Magnetic-Based Interface Enabling Pressure Force and Shear Force Input Applied to Front and Back of a Smartphone
Authors: Tsuchida Taichi , Fujita Kazuyuki , Ikematsu Kaori , Sarcar Sayan , Takashima Kazuki , Kitamura Yoshifumi
Published: November 2022

We propose a novel phone-case-shaped interface named TetraForce, which enables four types of force input consisting of two force directions (i.e., pressure force and shear force) and two force-applied surfaces (i.e., touch surface and back surface) in a single device. Force detection is achieved using the smartphone's built-in magnetometer (and supplementary accelerometer and gyro sensor) by estimating the displacement of a magnet attached to a 3-DoF passively movable panel at the back. We conducted a user study (N=12) to investigate the fundamental user performance by our interface and demonstrated that the input was detected as intended with a success rate of 97.4% on average for all four input types. We further conducted an ideation workshop with people who were involved in human-computer interaction (N=12) to explore possible applications of this interface, and we obtained 137 ideas for applications using individual input types and 51 possible scenarios using them in combination. Organizing these ideas reveals the advantages of each input type and suggests that our interface is useful for applications that require complex operations and that it can improve intuitiveness through elastic feedback.
A Survey of Augmented Piano Prototypes: Has Augmentation Improved Learning Experiences?
Authors: Deja Jordan Aiko , Mayer Sven , Čopič Pucihar Klen , Kljun Matjaž
Published: November 2022

Humans have been developing and playing musical instruments for millennia. With technological advancements, instruments were becoming ever more sophisticated. In recent decades computer-supported innovations have also been introduced in hardware design, usability, and aesthetics. One of the most commonly digitally augmented instruments is the piano. Besides electronic keyboards, several prototypes augmenting pianos with different projections providing various levels of interactivity on and around the keyboard have been implemented in order to support piano players. However, it is still unclear whether these solutions support the learning process. In this paper, we present a systematic review of augmented piano prototypes focusing on instrument learning based on the four themes derived from interviews with piano experts to understand better the problems of teaching the piano. These themes are (i) synchronised movement and body posture, (ii) sight-reading, (iii) ensuring motivation, and (iv) encouraging improvisation. We found that prototypes are saturated on the synchronisation themes, and there are opportunities for sight-reading, motivation, and improvisation themes. We conclude by presenting recommendations on augmenting piano systems towards enriching the piano learning experience as well as on possible directions to expand knowledge in the area.