bluuebunny/crossref_metadata_2025 huggingface dataset:
Fuzzy Recurrence Plots for Shallow Learning-Based Blockage Detection in a Centrifugal Pump Using Pre-Trained Image Recognition Models
Authors: Ranawat Nagendra Singh , Prakash Jatin , Miglani Ankur , Kankar Pavan Kumar
Published: April 2023

Rags, dusts, foreign particles, etc., are the primary cause of blockage in the centrifugal pump and deteriorate the performance. This study elaborates an experimental and data-driven methodology to identify suction, discharge, and simultaneous occurrence of both blockages. The discharge pressure signals are acquired and denoised using CEEMD. The fuzzy recurrence plots obtained from denoised signals are attempted to classify using three pre-trained models: Xception, GoogleNet, and Inception. None of these models are trained on such images; thus, features are extracted from different pooling layers which include shallow features too. The features extracted from different layers are fed to four shallow learning classifiers: Quadratic SVM, Weighted k-nearest network, Narrow Neural network, and subspace discriminant classifier. The study finds that subspace discriminant achieves the highest accuracy of 97.8% when trained using features from second pooling of Xception model. Furthermore, this proposed methodology is implemented at other blockage conditions of the pump. The subspace discriminant analysis outperforms the other selected shallow classifier with an accuracy of 93% for the features extracted from the first pooling layer of the Xception model. Therefore, this study demonstrates an efficient method to identify pump blockage using pre-trained and shallow classifiers.
Obtaining a single-photon weak value from experiments using a strong (many-photon) coherent state
Authors: Wiseman Howard M. , Steinberg Aephraim M. , Hallaji Matin
Published: April 2023

A common type of weak-value experiment prepares a single particle in one state, weakly measures the occupation number of another state, and post-selects on finding the particle in a third state (a “click”). Most weak-value experiments have been done with photons, but the heralded preparation of a single photon is difficult and slow of rate. Here, we show that the weak value mentioned above can be measured using strong (many-photon) coherent states, while still needing only a click detector such as an avalanche photodiode. One simply subtracts the no-click weak value from the click weak-value and scales the answer by a simple function of the click probability.
Tribological behavior of WC/WCN/CNx coatings deposited by high power impulse magnetron sputtering
Authors: Flores-Cova L. , Broitman E. , Jimenez O. , Flores-Martínez M.
Published: April 2023

Carbon-based coatings (WC/WCN/CNx) were deposited by high power impulse magnetron sputtering and direct current magnetron sputtering on the AISI 52100 alloy; no external heating was applied during deposition. Four bias voltages (−25, −50, −75, and −100 V) were used to analyze the bias effect on coating properties. Hardness was related to the sp3 content, coating adhesion depended on ion flux arriving at the substrate, and amorphous coatings were obtained at higher bias voltage. The coating showed a coefficient of friction of about 0.3, and the wear rate was reduced 100 times. Wear tracks were analyzed by Raman spectroscopy, indicating the graphitization of the coating during sliding.
Superconformal silicon carbide coatings via precursor pulsed chemical vapor deposition
Authors: Huang Jing-Jia , Militzer Christian , Wijayawardhana Charles A. , Forsberg Urban , Pedersen Henrik
Published: April 2023

In this work, silicon carbide (SiC) coatings were successfully grown by pulsed chemical vapor deposition (CVD). The precursors silicon tetrachloride (SiCl4) and ethylene (C2H4) were not supplied in a continuous flow but were pulsed alternately into the growth chamber with H2 as a carrier and a purge gas. A typical pulsed CVD cycle was SiCl4 pulse—H2 purge—C2H4 pulse—H2 purge. This led to growth of superconformal SiC coatings, which could not be obtained under similar process conditions using a constant flow CVD process. We propose a two-step framework for SiC growth via pulsed CVD. During the SiCl4 pulse, a layer of Si is deposited. In the following C2H4 pulse, this Si layer is carburized, and SiC is formed. The high chlorine surface coverage after the SiCl4 pulse is believed to enable superconformal growth via a growth inhibition effect.
Effect of focus ring with external circuit on cathode edge sheath dynamics in a capacitively coupled plasma
Authors: Xiao Yuhua , Brandon Joel , Morsell Joshua , Nam Sang Ki , Bae KiHo , Lee Jang-Yeob , Shannon Steven
Published: April 2023

Capacitively coupled plasmas are widely used in semiconductor processes. The control of plasma to obtain uniform deposition and etching is an open problem, particularly within a few millimeters of the substrate edge. Complex material stacks commonly referred to as focus rings are placed at the wafer edge to provide uniform processes across the entire substrate but have limitations with regard to process window and eventual material erosion. One approach is to combine a focus ring with a tunable external circuit ground path termination to extend the plasma uniformity to the wafer edge over a wider process space. The external circuit coupling focus ring to the ground influences the ion energy profile and the ion angular profile by changing the impedance between the focus ring and the ground and allows wafer edge tuning over a wide range of operating parameters. In this work, it is found that the adjustable external circuit can control the partitioning of bias and RF voltages between the RF powered and passively coupled plasma facing surfaces. The focus ring with an external circuit assembly can also control the spatial distribution of plasma density and, therefore, improve the sheath edge profile. These results point to possible source designs for engineering the distribution of power dissipation and the electric field of the wafer edge in industrial plasma reactors.
Limiting reagent conditions to control inorganic loading in AlOx–PET hybrid fabrics created through vapor-phase infiltration
Authors: McGuinness Emily K. , Manno Haley V. , Pyronneau Kira , Jean Benjamin C. , McClelland Nicole R. , Losego Mark D.
Published: April 2023

In this work, the vapor-phase infiltration (VPI) of polyethylene terephthalate (PET) fabrics with trimethylaluminum (TMA) and coreaction with water vapor is explored as a function of limiting TMA reagent conditions versus excess TMA reagent conditions at two infiltration temperatures. TMA is found to sorb rapidly into PET fibers, with a significant pressure drop occurring within seconds of TMA exposure. When large quantities of polymer are placed within the chamber, minimal residual precursor remains at the end of the pressure drop. This rapid and complete sorption facilitates the control of inorganic loading by purposely delivering a limited quantity of the TMA reagent. The inorganic loading for this system scales linearly with a Precursor:C=O molar ratio of up to 0.35 at 140 °C and 0.5 at 80 °C. After this point, inorganic loading is constant irrespective of the amount of additional TMA reagent supplied. The SEM analysis of pyrolyzed hybrids indicates that this is likely due to the formation of an impermeable layer to subsequent infiltration as the core of the fibers remains uninfiltrated. The Precursor:C=O molar ratio in the subsaturation regime is found to tune the hybrid fabric morphology and material properties such as the optical properties of the fabric. Overall, this work demonstrates how a reagent-limited processing route can control the inorganic loading in VPI synthesized hybrid materials in a simpler manner than trying to control kinetics-driven methods.
7.5 kV, 6.2 GW cm−2 NiO/β-Ga2O3
vertical rectifiers with on–off ratio greater than
1013
Authors: Li Jian-Sian , Chiang Chao-Ching , Xia Xinyi , Wan Hsiao-Hsuan , Ren Fan , Pearton S. J.
Published: April 2023

Vertical geometry NiO/β n-Ga2O/n+ Ga2O3 heterojunction rectifiers with contact sizes from 50 to 200 μm diameter showed breakdown voltages (VB) up to 7.5 kV for drift region carrier concentration of 8 × 1015 cm−3. This exceeds the unipolar 1D limit for SiC and was achieved without substrate thinning or annealing of the epi layer structure. The power figure-of-merit, VB2/RON, was 6.2 GW cm−2, where RON is the on-state resistance (9.3–14.7 mΩ cm2). The average electric field strength was 7.56 MV/cm, approaching the maximum for β-Ga2O3. The on–off ratio switching from 5 to 0 V was 2 × 1013, while it was 3 × 1010–2 × 1011 switching to 100 V. The turn-on voltage was in the range 1.9–2.1 V for the different contact diameters, while the reverse current density was in the range 2 × 10−8–2 × 10−9 A cm−2 at −100 V. The reverse recovery time was 21 ns, while the forward current density was >100 A/cm2 at 5 V.
Hydrophobic Si nanopillar array coated with few-layer MoS2 films for surface-enhanced Raman scattering
Authors: Ko Tsung-Shine , Chen Yen-Lun , Shieh Jiann , Chen Szu-Hung , Syu Jing-Yang , Chen Guan-Long
Published: April 2023

In this study, we covered Si nanopillar (NP) array with few-layer MoS2 films to convert their wettability characteristics from hydrophilic to hydrophobic for applications as a surface-enhanced Raman scattering (SERS) substrate. The Si NP array was fabricated using a semiconductor process. We then sulfurized and transferred MoO3 films coated onto the Si NP array to MoS2 films. The surface morphology and cross-sectional profile of the MoS2-coated Si NP array structure was examined using scanning electron microscopy and transmission electron microscopy. The SERS results indicate that the substrate exhibits a favorable enhancement factor of 1.76 × 103 and a detection limit of approximately 10−5M for Rhodamine 6G (R6G) utilized as the test molecule, attributed to the charge transfer (CT) mechanism at the interface between MoS2 and R6G. Contact angle measurements showed that the MoS2-coated Si NP array possesses a hydrophobic surface. Our results suggest that an MoS2-coated Si NP array with CT and hydrophobicity characteristics is extremely promising SERS substrates for SERS applications.
Assessing cognitive effects of transportation noise on office workers with physiology and task performance
Authors: Park Heui Young , Vigeant Michelle C. , Dittberner Andrew
Published: April 2023

Noise typically present in offices can negatively impact workers’ mental workload and task performance. This study investigated how transportation noise in open offices when windows are open can influence workers’ task performance, physiology (brain activity, heart rate variability, and skin resistance), and subjective ratings, as previous literature works often show inconclusive results or use unrealistic, simulated acoustic conditions. Subjects were given two cognitive tasks, mental arithmetic and digit span, while wearing three physiological measurement devices: an electroencephalography (EEG) headset, electrocardiogram (ECG) sensors, and electrodermal activity (EDA) sensors. After a baseline measurement, both the physiological markers and task performance were recorded for a training session, a quiet condition, and two transportation noise conditions with sound pressure levels of 50 and 70 dBA, respectively. Recorded rail noise was auralized in an anechoic chamber with a 32-loudspeaker array to simulate transportation noise heard when sitting in an office with an open window. Subjective rating questions regarding the acoustic environment and self-perception of mental workload and performance were administered after each acoustic condition. The effects of different acoustic conditions on cognitive task performance, physiological data, and subjective ratings were analyzed with a repeated measures MANOVA. Findings from this study will be presented.
Clinical trials of sonothrombolysis for Acute Coronary Syndromes
Authors: Mathias Wilson
Published: April 2023

Diagnostic high mechanical index (MI) ultrasound in conjunction with microbubble infusion in patients with acute ST-elevation myocardial infarction (STEMI) may be a method of achieving early recanalization, (sonothrombolysis). To evaluate the safety, efficacy and prognostic impact of sonothrombolysis in patients with acute coronary syndromes (ACS). We will randomize 540 patients with anterior STEMI in the “High Ultrasound Mechanical Index and MicrobuBBLEs to reduce acute myocardial infarction burden” (HUBBLE-I). Sonothrombolysis (50 min) was performed using multiple intermittent high MI impulses when microbubbles were imaged within the risk area (Therapy Group) or only 3 projections of low MI imaging alone plus microbubbles (Control Group) in 5 patient subgroups: G1-STEMI pre-PCI; G2-STEMI after lytic therapy; G3-Unstable angina and non-STEMI; G4-STEMI post-PCI; G5-STEMI pre-PCI treated in ambulances. Recanalization, ejection fraction, troponin and MB-CK levels were acquired at baseline, pre-PCI and follow-up. Global longitudinal strain was serially measured. The number of patients randomized to control versus therapy was 47(23/24), as follows: G1- 12 (5/7); G2- 13 (9/4); G3- 14 (8/6); G4- 8 (4/4) and G5- 0(0/0). This multicenter, Phase III randomized trial in patients with ACS treated by sonothrombolysis will assess safety, efficacy, and prognostic impact of this therapy.
Unnatural hearing—3D printing functional polymers as a path to bio-inspired microphone design
Authors: Reid Andrew
Published: April 2023

In nature, auditory organs are rarely passive transducers of their environment. Highly localized material properties and complex interdependencies mechanically filter the acoustic signal, reducing the burden of signal processing to the nervous system. Capturing these design traits in engineered systems is important for device miniaturization and energy efficiency, but manufacturing a functional electromechanical device, like a microphone, at the microscale using biologically inspired 3D designs and highly anisotropic materials remains extremely challenging. Our research uses one-pot synthesis methods for a variety of tissue-like hydrogels, polymers, and functionalized piezoelectric composites that are compatible with vat-based photopolymerization 3D printing. These materials can be used to produce reproductions of microphone designs using functional photopolymers for the conductive, piezoelectric, elastomeric, and structural elements. Used to produce mimetic structures, for example, in a device based on the directional sensitivity of the parasitoid fly Ormia ochracea, we can reproduce O. ochracea’s sound localization capability while addressing the impracticalities in frequency, sensitivity and scale of MEMS or micromachined designs. Each of the materials used has a unique set of acoustic, electrical and mechanical properties which can be tailored by altering the synthesis process leading to a truly vast design space which we are only beginning to explore.
American Football Soft-Shell Helmet Covers Reduce Head Impact Severity: A Critically Appraised Topic
Authors: O’Connell Kayla , Brown Christopher , Tripp Patricia M.
Published: April 2023

Focused Clinical Question: Do soft-shell helmet covers reduce head impact severity in American football helmets? Clinical Bottom Line: There is consistent SORT level C evidence to support that soft-shell helmet covers reduce measures of head impact severity and measures of linear and rotational acceleration. The impact reductions occurred at magnitudes less than the average reported concussive impact, which limits the application of the evidence with respect to concussion incidence or risk among American football players.
Comment on “Metabolic scaling is the product of life-history optimization”
Authors: Froese Rainer , Pauly Daniel
Published: April 2023

White
et al
. (Science 377, p. 834–839, 2022) propose that reproduction reduces the somatic growth of animals. This contradicts the common observations that non-reproducing adults are not larger than those that reproduced as well as the very example the authors provide of a fish that reproduces while its growth continues to accelerate, which is common in larger fish.
Minimizing buried interfacial defects for efficient inverted perovskite solar cells
Authors: Zhang Shuo , Ye Fangyuan , Wang Xiaoyu , Chen Rui , Zhang Huidong , Zhan Liqing , Jiang Xianyuan , Li Yawen , Ji Xiaoyu , Liu Shuaijun , Yu Miaojie , Yu Furong , Zhang Yilin , Wu Ruihan , Liu Zonghao , Ning Zhijun , Neher Dieter , Han Liyuan , Lin Yuze , Tian He , Chen Wei , Stolterfoht Martin , Zhang Lijun , Zhu Wei-Hong , Wu Yongzhen
Published: April 2023

Controlling the perovskite morphology and defects at the buried perovskite-substrate interface is challenging for inverted perovskite solar cells. In this work, we report an amphiphilic molecular hole transporter, (2-(4-(bis(4-methoxyphenyl)amino)phenyl)-1-cyanovinyl)phosphonic acid, that features a multifunctional cyanovinyl phosphonic acid group and forms a superwetting underlayer for perovskite deposition, which enables high-quality perovskite films with minimized defects at the buried interface. The resulting perovskite film has a photoluminescence quantum yield of 17% and a Shockley-Read-Hall lifetime of nearly 7 microseconds and achieved a certified power conversion efficiency (PCE) of 25.4% with an open-circuit voltage of 1.21 volts and a fill factor of 84.7%. In addition, 1–square centimeter cells and 10–square centimeter minimodules show PCEs of 23.4 and 22.0%, respectively. Encapsulated modules exhibited high stability under both operational and damp heat test conditions.
Cell and Tissue Tropism of Brucella spp.
Authors: Carvalho Thaynara Parente de , Silva Laice Alves da , Castanheira Thaís Larissa Lourenço , Souza Tayse Domingues de , Paixão Tatiane Alves da , Lazaro-Anton Leticia , Tsolis Renee M. , Santos Renato Lima
Published: April 2023

Brucellaspp. are facultatively intracellular bacteria that can infect, survive, and multiply in various host cell typesin vivoand/orin vitro. The genusBrucellahas markedly expanded in recent years with the identification of novel species and hosts, which has revealed additional information about the cell and tissue tropism of these pathogens.
The Mystery of Candida albicans Hyphal Morphogenesis in the Macrophage Phagolysosome
Authors: Krysan Damian J.
Published: April 2023

C. albicans
transitions between budding yeast and filamentous hyphal forms in a process that is tightly associated with its virulence. This transition also occurs after the fungus has been phagocytosed by macrophages.
Massive mature cystic teratoma of the head and neck, masquerading as a glial choristoma, causing respiratory compromise of a neonate
Authors: Suttle Tessa Kirsty , Els Timothy
Published: April 2023

Glial choristoma of the head and neck is a rare, benign congenital malformation consisting of a mass of heterotopic glial cells. In cases involving the upper aerodigestive tract, this can present with upper airway obstruction. In the acute setting, this can lead to diagnostic challenges due to the broad differential, as well as the additional difficulties in obtaining appropriate imaging and tissue samples due to the potential risk of airway compromise. We present a case of a neonate born with a large heterogenous mass involving the upper aerodigestive tract and multiple deep neck spaces which resulted in upper airway compromise requiring emergency surgical intervention in the form of a paediatric tracheostomy. We will discuss the histological findings which initially suggested a glial choristoma, work-up and treatment of this patient with the aim of supplementing the limited existing clinical knowledge of this congenital anomaly and understanding the implications of a paediatric tracheostomy in our setting.
Scoping review protocol exploring the relationship between food insecurity, mental health and diet intake among adolescents across the globe
Authors: Nkwanyana Akhona , Florence Maria , Swart Elizabeth Catherina
Published: April 2023

Introduction

Studies, exploring the effect of food insecurity on physical and mental health, have shown that food insecurity is associated with lower self-reports of physical and mental health. With the COVID-19 pandemic, food insecurity has increased leading to higher risks of poor mental health. Despite evidence of the negative implications of food insecurity on mental health, there is a paucity of research on these variables for adolescents specifically. The current evidence shows there is a gap in adolescent centred research linking mental health and food insecurity globally. Adolescence is a crucial period of development where habits, nutritional inadequacies linked to food insecurity and mental health problems formed due to these inadequacies can be conveyed into adulthood. The aim of this study is to systematically scope the literature exploring the relationship between mental health, food (in)security and/or diet intake of adolescents.

Methods

This review will be guided by Arksey and O’Malley’s extended framework. The search strategy was developed by two of the authors and will be used to search literature from January 2012 to December 2022 in PubMed, Academic search complete, PsychARTICLES, Google, ScienceDirect, Scopus and Web of science core collection. Searching published and unpublished literature will be done in the chosen databases. References used in included literature will be reviewed for additional studies/sources. Articles will be assessed for eligibility by two reviewers, and any discrepancies reviewed by a third reviewer. The inclusion and exclusion criteria will be used for screening. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagram will be used to document the selection process. A narrative summary and descriptive analysis will be used to summarise and report the extracted data.

Ethics and dissemination

Approval for this study has been granted by the University of the Western Cape Biomedical Research Ethics Committee (BM21/8/3). Strict measures will be followed to ensure methodological rigour.
Mental health of new and recent graduates during the university-to-work transition: a scoping review protocol
Authors: Zayts Olga , Edmonds David Matthew , Kong Brandon Chee Kin , Fortune Zoë
Published: April 2023

Introduction

University students face challenges when starting their careers and entering the workforce after tertiary education is associated with negative psychological outcomes. The planned scoping review will synthesise the literature on the impact of university-to-work transitions on the mental health of new and recent graduates. We will describe the characteristics and main findings of the studies, and will examine the variables associated with, and the theories used to explain, the relationship between transitions to work and graduates’ mental health.

Methods

We will search the following databases: Scopus, Web of Science, ERIC, PSYCINFO, Social Sciences Citation Index, CINAHL Plus, Ovid MEDLINE and Google Scholar, to locate published and unpublished literature. The included studies will focus on undergraduate and postgraduate university students during planned or current university-to-work transitions, as well as early-career workers. We will include studies involving people who have left or are in their final year of study, are undergoing career transition preparation or have worked for no longer than 3 years since graduation. Studies from all countries, those published in English and since 2000, will be included. We will use a set of predefined search terms and we will extract studies using the EndNote V.20 reference management software. Two reviewers will screen and assess the identified studies using the Covidence software. Finally, we will present the data in a summary table and will qualitatively analyse the studies using thematic analysis.

Ethics and dissemination

Our scoping review does not require ethical approval. The scoping review’s findings will be disseminated in peer-reviewed journal articles and conference presentations, and will inform the development of training resources for different stakeholders as part of a wider research project.

Trial registration number

The study has been registered with the Open Science Framework (https://osf.io/gw86x).
The existence of null circular geodesics outside extremal spherically symmetric asymptotically flat hairy black holes
Authors: Peng Yan
Published: April 2023

The existence of null circular geodesics in the background of non-extremal spherically symmetric asymptotically flat black holes has been proved in previous works. An interesting question that remains, however, is whether extremal black holes possess null circular geodesics outside horizons. In the present paper, we focus on the extremal spherically symmetric asymptotically flat hairy black holes. We show the existence of the fastest circular trajectory around an extremal black hole. As the fastest trajectory corresponds to the position of null circular geodesics, we prove that null circular geodesics exist outside extremal spherically symmetric asymptotically flat hairy black holes.
The validity of the BCS-like theory of Fermi-liquid superconductivity in overdoped cuprates
Authors: Dzhumanov S. , Sheraliev M. U.
Published: April 2023

In this paper, we study the key and challenging issues arising in the physics of doped cuprate superconductors, which depending on the doping level (or the Fermi energy [Formula: see text]) and the characteristic energy [Formula: see text] of the attractive interaction between the charge carriers (holes or electrons) might be either in the limit of fermionic (weakly-bound) Cooper pairs just like in ordinary metals or in the limit of bosonic (tightly-bound) Cooper pairs. We argue that the underlying mechanism of superconductivity in doped cuprates depends on the fermionic or bosonic nature of Cooper pairs. We examine the validity criterion of the Bardeen–Cooper–Schrieffer (BCS)-like theory of Fermi-liquid superconductivity in these materials and determine the doping level at which this criterion is well satisfied. We find that the specific overdoped cuprates (with [Formula: see text] or [Formula: see text][Formula: see text]eV) can become the BCS-type superconductors. Using a pertinent BCS-like pairing theory, we calculate the superconducting order parameter (defined as a BCS-like gap [Formula: see text]) and the critical temperature [Formula: see text] of the superconducting transition and the doping dependences of [Formula: see text] and [Formula: see text] in various overdoped cuprates. Our results for [Formula: see text] and [Formula: see text] in specific overdoped cuprates are in fair agreement with the experimental findings reported for these systems.
Nickel oxide nanoparticles: Synthesis and characterization for optical studies
Authors: Shanmugapriya B. , Sivasankari G. , Kannagi K. , Sankari P. , Kiruthika R. A. , Pavithra N. , Al-Zaharani Asla A. , Sarif Mahanim
Published: April 2023

In this study, the co-precipitation approach was used to make nanostructured nickel oxide (NiO) commencing with sodium hydroxide (NaOH) and nickel (II) chloride hexahydrate (NiCl2[Formula: see text]6H2O). Through the use of X-ray diffraction (XRD), scanning electron microscopes (SEM), UV-visible (UV–Vis) absorption, and Fourier transform infrared (FTIR) imaging, structural and optical studies were investigated. FTIR, photoluminescence (PL), cyclic voltammetry (CV) studies are taken. The synthesized nanoparticles were annealed at [Formula: see text]C and [Formula: see text]C. The face-centered cubic (FCC) structure of the NiO and highly crystallized nanoparticles were revealed by XRD investigations. Observation of FTIR spectra validated the composition of functional groups. Scanning electron microscopy image shows the average size is 24 nm. NiO optical band gap at [Formula: see text]C (3.37 eV) and [Formula: see text]C (2.7 eV) is revealed from UV studies. From CV graph, the sample annealing at [Formula: see text]C and [Formula: see text]C the specific capacitance was 543.6 and 519.8 F/g, respectively. This study signifies the supercapacitor application of nanosized metal oxide.
Resisting China’s ICT Influence in Sub-Saharan Africa: A Bandwagoning-for-Profit Perspective
Authors: YANG DOMINGO I-KWEI
Published: April 2023

In light of the increasingly pivotal role of Sub-Saharan Africa (SSA) in the escalating US-China competition, this paper explores why US-led anti-Chinese information and communications technology (ICT) campaigns have not resonated with African countries. It notes that Washington’s narrative about China’s ICT activities in the region corresponds with Stephen Walt’s “balance of threat,” emphasizing the threat of China and demanding that African states balance against its cyber aggression. It argues, however, that American policymakers should focus more on Randall Schweller’s “bandwagoning for profit” to resist China’s ICT influence in the region because the pitfalls of malignant Chinese ICTs are outweighed by the opportunities and prospects of mobile-driven digital transformation there. This paper explores Washington’s unsatisfactory approach toward the SSA, traces China’s long-term penetration into the digital sector among African countries, and argues that the country’s strategic objective in the region is to establish a digital ecosystem filled with Chinese technologies and devices. It then evaluates the region’s digital prospects and the yearning among African countries to learn from China’s late development path. The paper concludes that China is not winning hearts and minds in the region and both strategies of balancing and bandwagoning persist in Sino-African relations. African countries would not always bandwagon with China if there were more alternatives. To resist the country’s ICT influence in the region, Washington should engage with Africa’s ICT industries, deepen trade relations and help to grow its digital economy.
How to Limit Label Dissipation in Neural-network Validation: Exploring Label-free Early-stopping Heuristics
Authors: Ameryan Mahya , Schomaker Lambert
Published: April 2023

In recent years,
deep learning (DL)
has achieved impressive successes in many application domains, including Handwritten-Text Recognition. However, DL methods demand a long training process and a huge amount of human-based labeled data. To address these issues, we explore several label-free heuristics for detecting the early-stopping point in training convolutional-neural networks: (1) Cumulative Distribution of the
standard deviation of kernel weights (SKW)
; (2) the moving standard deviation of SKW, and (3) the standard deviation of the sum of weights over a window in the epoch series. We applied the proposed methods to the common RIMES and Bentham data sets as well as another highly challenging historical data set. In comparison with the usual stopping criterion which uses labels for validation, the label-free heuristics are at least 10 times faster per epoch when the same training set is used. The use of alternative stopping heuristics may require additional epochs, however, they never require the original computing time. The character error rate (%) on the test set of the label-free heuristics is about a percentage point less in comparison to the usual stopping criterion. The label-free early-stopping methods have two benefits: They do not require a computationally intensive evaluation of a validation set per epoch and all labels can be used for training, specifically benefitting the underrepresented word or letter classes.
RoSense
Authors: Zhu Yinan , Duan Chunhui , Ding Xuan
Published: April 2023

RFID sensing leveraging backscatter signal features (e.g., phase shift) from tags has gained increasing popularity in numerous applications, but also suffers from negative impacts of environmental multipaths. Past works to address it rely on extra customized devices, labor-intensive offine training or frequency channel hopping, all of which are nonubiquitous or ineffective for real-life adoption. This paper presents RoSense, a universal method to alleviate multipath reflections' impacts by spinning the reader antenna, thus enabling more robust RFID sensing. Besides, RoSense requires no RF devices or offline training, and operates in a nonintrusive manner. The key insight of RoSense is to exploit two properties of line-of-sight (LOS) signal when spinning the antenna, i.e., the linearity of phase changes and stability of received signal strength to attenuate the non-linear and non-monotonic effect of multipath signals and refine the phase shift of LOS signal. We have implemented a prototype of RoSense with COTS devices and studied two cases for evaluation: material identification and object localization. Experimental results show that RoSense can improve the material identification accuracy by 16.22% and reduce the mean localization error by 39.93%, greatly outperforming the state-of-the-art solutions.
Tackling Heterogeneous Traffic in Multi-access Systems via Erasure Coded Servers
Authors: Choudhury Tuhinangshu , Wang Weina , Joshi Gauri
Published: April 2023

In cloud systems, the number of servers is fixed, and each server is usually dedicated to a job type. However, the traffic of various jobs can vary across time, and hence, a rigid allocation of servers does not perform well. In this paper, we propose the addition of erasure-coded servers that can flexibly serve multiple job types without additional storage cost. We show that coding expands the service capacity region, thus enabling the system to handle variable traffic. Moreover, we characterize the response time of the coded system in various arrival rate regimes and show that adding even a small number of coded servers can significantly reduce the mean response time.
The Application of Intelligent Generation Technology in the Visual Communication Design of Exhibition Brand
Authors: Cao Zeyu
Published: April 2023

Since the beginning of the new century, information technology has advanced by leaps and bounds, and intelligent technology has made breakthroughs, speech recognition, and image recognition. In the development of medium and long-term exhibition brands, intelligence and modernization are taken as one of the development tasks. The visual communication design of brand logo is the graphical post symbol language of brand trademark, which is the silent transmission of brand. As long as you see a certain brand logo, its product characteristics and values can emerge in your mind. It is very easy to identify. Graphics, colors, and fonts are its main visual elements. Exhibition is a very promising industry in the modern business economy, and it is one of the best platforms for enterprises to promote their brands. Paying attention to the brand visual communication design of exhibitions is of great significance and value to enhance the overall impression of enterprises in the minds of consumers. This article explores the value and principles of corporate brand in the exhibition industry. Research shows that corporate brand visual communication design in exhibitions should be based on the brand architecture system, reflect the connotation of brand culture, and highlight brand design innovation. Taking corporate brand visual communication design in the exhibition industry as the research object, to explore its design value, the value of corporate brand visual communication design in commercial exhibitions is very great, and enterprises must attach great importance to commercial exhibitions. From the perspective of visual communication design, it can be parsed into three levels: color, space shaping, and graphic and text conformity. To reconstruct brand design, companies must make layout, innovation, and reconstruction of these three levels and strengthen commercial exhibitions. The impact and appeal of the visual communication design of the Chinese enterprise brand can truly enhance the influence and popularity of the enterprise brand and ultimately promote the sustainable development of the enterprise brand.
Unknown Binary Protocol Recognition Algorithm Based on One Class of Classification and One‐Dimensional CNN
Authors: Yin Shizhuang , You Zhifeng , Hu Qiwei , Shi Quan , Li Juan
Published: April 2023

In order to solve the problem that there are a large number of unknown protocols on the network, which affect the network management and network security in varying degrees, an unknown binary protocol identification method is proposed. On the premise that the center cluster of unknown protocols is obtained by the clustering algorithm, the unknown protocols for network traffic are identified by combining one‐class of classification with one‐dimensional CNN classification technology. At first, a class of classification algorithm is used to select the unknown protocols, and then, the labeled protocol data obtained by clustering are used to train the one‐dimensional CNN model, and the classified binary protocol packets are directly used as the input of the one‐dimensional convolution neural network. After the classification of the CNN model, the unknown protocols are finally identified. The experimental results show that the proposed classification and recognition method is better than the traditional CNN and SVM algorithms, and the maximum frequency pooling is better than the traditional pooling method.
Design of Metamaterial Antenna Based on the Mathematical Formulation of Patch Antenna for Wireless Application
Authors: Prasad Jones Christydass S. , Suresh Kumar S. , Nishok V. S. , Saravanakumar R. , Devakirubakaran S. , Deepa J. , Sangeetha K.
Published: April 2023

For WLAN/WIMAX applications, a brand-new tree-shaped metamaterial-loaded microstrip antenna is suggested. The reduced ground plane size and 4.4 dielectric constant (r) and 0.02 loss tangent (δ) dielectric are used to manufacture the 15 × 16 × 1.6 mm3 microstrip antenna. Two X-shaped slots are added to achieve the characteristics needed for WIMAX applications at 5.5 GHz. Additionally, a split-ring resonator is added to the structure to increase its bandwidth. It runs for WLAN applications with a center frequency of 5.8 GHz. The proposed structure’s measured impedance bandwidth is 45.39% with SRR and 53.48% without SRR, respectively. The proposed antenna is capable of satisfying the major requirements of modern wireless devices such as multiband operation, compact size, large bandwidth, and planar structure. The best outcomes are attained with the aid of parametric analysis of feed width, ground height, and slot width. All electromagnetic simulations were performed using CST Studio software. The measured results and the simulation agree. The waveguide extraction approach is used to demonstrate the SRR’s permeability property. The suggested antenna had adequate impedance matching, was small, and had a wide bandwidth.
An Experimental Testing of Optimized Fuzzy Logic‐Based MPPT for a Standalone PV System Using Genetic Algorithms
Authors: Yahiaoui Fatah , Chabour Ferhat , Guenounou Ouahib , Bajaj Mohit , Hussain Bukhari Syed Sabir , Shahzad Nazir Muhammad , Pushkarna Mukesh , Mbadjoun Wapet Daniel Eutyche
Published: April 2023

The choice and the dimensioning of the controller for the maximum power point tracking (MPPT) are determined for the ideal energy efficiency of the photovoltaic (PV) systems. Many works have been developed in the field of MPPT methods, especially fuzzy logic controllers. However, these are robust if the parameters of the membership functions have been well designed. In this paper, the performances of an intelligent fuzzy logic controller (FLC)‐based MPPT method have been optimized by an evolutionary genetic algorithm (GA). The works presented in the literature have shown the efficiency of the proposed method compared to classical methods. In our paper, the validation of the experimental results obtained is given with respect to a reference signal. The control of the simulated PV source and the proposed method are built using the Simulink/Matlab environment and implemented on the dSPACE DS1104 controller to validate the practical execution of the suggested method. The standalone PV system has been tested in an emulated test bench experimentation. Experimental results confirm the efficiency of the proposed method and its high accuracy in handling fast varying load conditions.
A Compound Class of Unit Burr XII Model: Theory, Estimation, Fuzzy, and Application
Authors: Zayed Mohammad A. , Hassan Amal S. , Almetwally Ehab M. , Aboalkhair Ahmad M. , Al-Nefaie Abdullah H. , Almongy Hisham M.
Published: April 2023

The current research offers an enhanced three-parameter lifetime model that combines the unit Burr XII distribution with a power series distribution. The novel class of distribution is named the unit Burr XII power series (UBXIIPS). This compounding technique allows for the production of flexible distributions with strong physical meanings in domains such as biology and engineering. The UBXIIPS class includes the unit Burr XII Poisson (UBXIIP) distribution, the unit Burr XII binomial distribution, the unit Burr XII geometric distribution, and the unit Burr XII negative binomial distribution. The statistical properties of the class include formulas for the density and cumulative distribution functions, and limiting behaviour, moments and incomplete moments, entropy measures, and quantile function are provided. For estimating population parameters and fuzzy reliability for the UBXIIP model, maximum likelihood and Bayesian approaches are studied by the Metropolis–Hastings algorithm. For maximum likelihood estimators, the length of asymptotic confidence intervals is specified, whereas, for Bayesian estimators, the length of credible confidence intervals is assigned. A simulation investigation of the UBXIIP model was established to evaluate the performance of suggested estimates. In addition, the UBXIIP distribution is explored using real-world data. The UBXIIP distribution appears to offer some benefits in understanding lifetime data when compared to unit Weibull, beta, Kumaraswamy, Kumaraswamy Kumaraswamy, Marshall-Olkin Kumaraswamy, and Topp–Leone Weibull Lomax distributions.
Determination of Chemical Composition and Antimicrobial Activity of the CO2 Extract of Eryngium planum L.
Authors: Arykbayeva Aliya B. , Ustenova Gulbaram O. , Sharipov Kamalidin O. , Beissebayeva Ulzhan T. , Kaukhova Irina E. , Myrzabayeva Auyes , Gemejiyeva Nadezhda G.
Published: April 2023

The article presents parameters for obtaining a carbon dioxide extract from the subterranean part of Eryngium planum that contains a valuable set of organic substances and has a certain antimicrobial effect. Methods. Raw materials were collected in the Almaty region (Republic of Kazakhstan). The CO2 extract of Eryngium planum herbs was obtained under subcritical conditions. A gas chromatograph with a mass spectrometric detector was used to determine the compositional breakdown of the extract. Antimicrobial activity was determined by two methods: the micromethod of serial dilutions and the disk-diffusion method. Three microbial test strains were used: Staphylococcus aureus ATCC 6538-P, Escherichia coli ATCC 8739, and Candida albicans ATCC 10231. Results. To extract biologically active substances from the subterranean part of Eryngium planum L., we have chosen carbon dioxide extraction technology, a technology for processing carbon dioxide (CO2) raw materials, which allows us to extract various substances in high concentrations. Carbon dioxide extraction technology is an effective and environmentally safe way to isolate various biologically active substances contained in medicinal plant raw materials. In the composition of the CO2 extract of Eryngium planum L. 43 components were identified, the main of which are α-linolenic acid, 8.30%; myristic acid, 6.40%; caryophyllene, 6.92%; spatulous, 6.62%; and other main identified compounds and their percentage. Conclusions. The study showed that the CO2 extract of Eryngium planum L. contains biologically active compounds that have a pronounced antimicrobial effect against clinically significant microorganisms, such as Escherichia coli, Staphylococcus aureus, and Candida albicans.
Development of a Simple Integrative Carbon Nanomaterial Microextraction Method with GC-MS for Assessing Pesticide Residues in Apples
Authors: Valenzuela Eduard F. , André Leiliane C. , Menezes Helvecio C. , Cardeal Zenilda L.
Published: April 2023

The present study describes an efficient analytical method for analyzing apple pesticide residues. This novel approach employs ultrasound-assisted cleaning (UAC), solid-phase microextraction (SPME), and gas chromatography/mass spectrometry (GC-MS). A fiber coating with carbon nanomaterials (CNMs) was used for the extraction process. The methodology underwent extraction process optimization and analytical method validation. Moreover, its applicability for detecting pesticides in apples was evaluated. The validation showed satisfactory results with linearity coefficients greater than 0.99 (R2 > 0.99) and linear working ranges from 0.5 ng·g−1 to 300.0 ng·g−1. The limits of detection and quantification (LODs and LOQs) ranged from 0.1 ng·g−1 to 0.3 ng·g−1 and from 0.5 ng·g−1 to 0.7 ng·g−1, respectively. The calculated recovery values ranged from 79% to 98%. The precision presented a relative standard deviation (RSD) lower than 14%. The validated method was applied to apple samples acquired from different markets and fruit stands in Belo Horizonte, Minas Gerais, Brazil. Organophosphate pesticides typically used in Brazilian apple production areas were detected in some samples. This study demonstrates the utility of UAC and CNM microextraction as an effective and highly efficient approach for analyzing pesticides in apples.
Numerical Study on Load Bearing Capacity of Root‐Caisson Foundation
Authors: Jayashree J. , Sathyapriya S. , Karthik V. , Periyasamy Selvakumar , Sundramurthy Venkatesa Prabhu
Published: April 2023

Innovation has been made in the caisson foundation to support a very large structure resting over a soft soil stratum known as the root‐caisson foundation. This technique was executed in China‐Yangtze River Bridge. The root caisson foundation was first implemented in the Yangtze River bridge and discovered that the root improves soil structure interaction and increases vertical bearing capacity by 100%. In the present research, a numerical study of root‐caisson foundation under combined vertical and horizontal loading was performed using ABAQUS software. Analysis was performed by varying the parameters of root caisson such as the inclination of roots (30°, 45°, 60°, and 90°) spacing(S) between the root floors with respect to diameter (D) of the caisson as (0.5°D, 0.6°D, and 0.75°D) with different loading conditions and results were compared with normal traditional caisson with the same length (L) to diameter (D) ratio. From the test results, the load‐settlement behavior of caisson is nonlinear for individual vertical, and lateral load tests and also the same for the combined loading conditions. It is found that the root‐caisson has a higher load bearing capacity as compared to that of the traditional caisson. Moreover, in combined loading, the load bearing capacity increases considerably, compared with the ultimate vertical and lateral load capacity.