bluuebunny/crossref_metadata_2025 huggingface dataset:
Origin of the current saturation level of p-doped silicon field emitters
Authors: Edler Simon , Schels Andreas , Herdl Florian , Hansch Walter , Bachmann Michael , Dudeck Markus , Düsberg Felix , Pahlke Andreas , Hausladen Matthias , Buchner Philipp , Schreiner Rupert
Published: December 2021

Using p-type semiconductors for field emitters is one simple way to realize an integrated current limiter to improve the lifetime of the cathode. In this work, the origin of the current saturation of p-type silicon emitters is investigated in detail. Single emitters are electrically characterized and compared to simulation results. With a simulation model considering a high surface generation rate and elevated tip temperature, a good agreement to the measured data is found. This observation is supported further by alteration of the surface experimentally. Electrical measurements after different treatments in hydrofluoric acid as well as heated and subsequent operation at room temperature are well explained by the influence of surface generation. Furthermore, it is shown that the field penetration leads to a small voltage drop and a strong geometry-dependent reduction of the field enhancement factor.
Experimental considerations in electron beam transport on a nanophotonic chip using alternating phase focusing
Authors: Shiloh Roy , Chlouba Tomáš , Hommelhoff Peter
Published: December 2021

Not long after the laser was invented, it has been marked as a candidate source of strong, high-frequency electromagnetic radiation for the acceleration of particles. Indeed, while today’s complex particle accelerator facilities are an astonishing culmination of decades of work contributed by generations of physicists, engineers, and a host of scientists, new trends and acceleration technologies have recently been proposed and demonstrated. One of these technologies involves the miniaturization of particle accelerators, which is achieved by replacing the radiofrequency (RF) electromagnetic fields accelerating the particles with fields in the optical frequency range using lasers. This entails using nanophotonics structures to provide the required field distribution. Recently, individual elements toward the nanophotonics counterpart of RF accelerators have been demonstrated. Similarly, active electron transport through such a structure has been shown, which was based on the concept of alternating phase focusing. In this contribution, we discuss and augment on the recently demonstrated principle of alternating phase focusing using optical frequencies and provide new insights from relevant simulations and experiments. In particular, we show how to identify possible imprecisions and parasitic effects from time-delay scans and discuss how the transmission of electrons through the nanometric structure depends on the temporal overlap between electron and laser pulses. We also show how the incidence angle of the electron beam can affect the measured transmission of electrons through the structure.
Determination of density profile by using the refractive index in a linearly salt-stratified fluid: An experiment for an advanced undergraduate laboratory
Authors: Cruz-Gómez R. C. , Velázquez-Muñoz F. A. , Salcedo-Castro J.
Published: December 2021

This paper describes a low-cost laboratory experiment designed to demonstrate the applicability of the refractive index to study stratification in fluids. The laser refractography method was applied to a linearly vertical density profile of a salt (NaCl) stratified water column. Next, an image processing procedure was performed, consisting of the binarization and edge detection of the laser beam and its subsequent second-order polynomial best fit. Quantitatively, the whole-field results compared well with the respective measured density profiles. This method allows one to obtain quantitative measurements of density profiles in stratified fluids with good accuracy, making it a suitable experimental method for laboratory demonstrations on fluids.
The Vaidya metric: Expected and unexpected traits of evaporating black
holes
Authors: Piesnack Julius , Kassner Klaus
Published: December 2021

The ingoing Vaidya metric is introduced as a model for a non-rotating uncharged black hole emitting Hawking radiation. This metric is expected to capture the physics of the spacetime for radial coordinates up to a small multiple (>1) of the Schwarzschild radius. For larger radii, it will give an excellent approximation to the spacetime geometry in the case of astrophysical black holes (M≥M⊙), except at extremely large distances from the horizon (exceeding the cosmic particle horizon). In the classroom, the model may serve as a first exploration of non-stationary gravitational fields. Several interesting predictions are developed. First, particles dropped early enough before complete evaporation of the black hole cross its horizon as easily as with an eternal black hole. Second, the Schwarzschild radius takes on the properties of an apparent horizon, and the true event horizon of the black hole is inside of it, because light can escape from the shrinking apparent horizon. Third, a particle released from rest close enough to the apparent horizon is strongly repelled and may escape to infinity. An interpretation is given, demonstrating that such a particle would be able to compete, for a short time, in a race with a photon.
Acoustic signatures of communicative dimensions in codified mother-infant interactions
Authors: Falk Simone , Audibert Nicolas
Published: December 2021

Nursery rhymes, lullabies, or traditional stories are pieces of oral tradition that constitute an integral part of communication between caregivers and preverbal infants. Caregivers use a distinct acoustic style when singing or narrating to their infants. Unlike spontaneous infant-directed (ID) interactions, codified interactions benefit from highly stable acoustics due to their repetitive character. The aim of the study was to determine whether specific combinations of acoustic traits (i.e., vowel pitch, duration, spectral structure, and their variability) form characteristic “signatures” of different communicative dimensions during codified interactions, such as vocalization type, interactive stimulation, and infant-directedness. Bayesian analysis, applied to over 14 000 vowels from codified live interactions between mothers and their 6-months-old infants, showed that a few acoustic traits prominently characterize arousing vs calm interactions and sung vs spoken interactions. While pitch and duration and their variation played a prominent role in constituting these signatures, more linguistic aspects such as vowel clarity showed small or no effects. Infant-directedness was identifiable in a larger set of acoustic cues than the other dimensions. These findings provide insights into the functions of acoustic variation of ID communication and into the potential role of codified interactions for infants' learning about communicative intent and expressive forms typical of language and music.
Suppression of caspase 8 activity by a coronin 1–PI3Kδ pathway promotes T cell survival independently of TCR and IL-7 signaling
Authors: Mori Mayumi , Ruer-Laventie Julie , Duchemin Wandrille , Demougin Philippe , Ndinyanka Fabrice Tohnyui , Wymann Matthias P. , Pieters Jean
Published: December 2021

Coronin 1 supports T cell survival by maintaining PI3Kδ-dependent repression of caspase 8 activity.
Bloodstream Infections Caused by
Magnusiomyces capitatus
and
Magnusiomyces clavatus
: Epidemiological, Clinical, and Microbiological Features of Two Emerging Yeast Species
Authors: Noster Janina , Koeppel Martin B. , Desnos-Olivier Marie , Aigner Maria , Bader Oliver , Dichtl Karl , Göttig Stephan , Haas Andrea , Kurzai Oliver , Pranada Arthur B. , Stelzer Yvonne , Walther Grit , Hamprecht Axel
Published: December 2021

Magnusiomyces clavatus
and
Magnusiomyces capitatus
are emerging yeasts with intrinsic resistance to many commonly used antifungal agents. Identification is difficult, and determination of susceptibility patterns with commercial and reference methods is equally challenging. For this reason, few data on invasive infections by
Magnusiomyces
spp. are available.
Abstracts from international emergency medicine journals
Authors: Production EMJ
Published: December 2021

EMJ has partnered with the journals of multiple international emergency medicine societies to share from each a highlighted research study, as selected by their editors. This edition will feature an abstract from each publication.
Hownotto count the health benefits of family planning
Authors: Zionts Jacob , Millum Joseph
Published: December 2021

Several influential organisations have attempted to quantify the costs and benefits of expanding access to interventions—like contraceptives—that are expected to decrease the number of pregnancies. Such health economic evaluations can be invaluable to those making decisions about how to allocate scarce resources for health. Yet how the benefits should be measured depends on controversial value judgments. One such value judgment is found in recent analyses from the Disease Control Priority Network (DCPN) and the Study Group for the Global Investment Framework for Women’s and Children’s Health. Noting the decrease in the number of pregnancies expected to result from providing access to family planning, DCPN and the Study Group claim that a substantial benefit of such interventions is averting the stillbirths and child deaths that would have resulted from those pregnancies. We argue that health economic analyses should not count such averted deaths as benefits in the same way as saved lives. First, by counting averted stillbirths and child deaths as a benefit but not counting as a cost the lives of babies who survive, DCPN and the Study Group implicitly commit themselves to antinatalism. Second, this method for calculating the benefits of family planning interventions implies that infertility treatments are harmful. Determining how potential people should be treated in health economic analyses will require grappling with population ethics.
Soluble ST2 concentrations associate with in-hospital mortality and need for mechanical ventilation in unselected patients with COVID-19
Authors: Omland Torbjorn , Prebensen Christian , Jonassen Christine , Svensson My , Berdal Jan Erik , Seljeflot Ingebjørg , Myhre Peder Langeland
Published: December 2021

Objective

Soluble ST2 (sST2) reflects inflammation, endothelial dysfunction and myocardial fibrosis, is produced in the lungs and is an established biomarker in heart failure. We sought to determine the role of sST2 in COVID-19 by assessing pathophysiological correlates and its association to in-hospital outcomes.

Methods

We enrolled 123 consecutive, hospitalised patients with COVID-19 in the prospective, observational COVID-19 MECH study. Biobank samples were collected at baseline, day 3 and day 9. The key exposure variable was sST2, and the outcome was ICU treatment with mechanical ventilation or in-hospital death.

Results

Concentrations of sST2 at baseline was median 48 (IQR 37–67) ng/mL, and 74% had elevated concentrations (>37.9 ng/mL). Higher baseline sST2 concentrations were associated with older age, male sex, white race, smoking, diabetes, hypertension and chronic kidney disease. Baseline sST2 also associated with the presence of SARS-CoV-2 viraemia, lower oxygen saturation, higher respiratory rate and increasing concentrations of biomarkers reflecting inflammation, thrombosis and cardiovascular disease. During the hospitalisation, 8 (7%) patients died and 27 (22%) survivors received intensive care unit (ICU) treatment. Baseline sST2 concentrations demonstrated a graded association with disease severity (median, IQR): medical ward 43 (36–59) ng/mL; ICU 67 (39–104) ng/mL and non-survivors 107 (72–116) ng/mL (p<0.001 for all comparisons). These associations persisted at day 3 and day 9 .

Conclusions

sST2 concentrations associate with SARS-CoV-2 viraemia, hypoxaemia and concentrations of inflammatory and cardiovascular biomarkers. There was a robust association between baseline sST2 and disease severity that was independent of, and superior to, established risk factors. sST2 reflects key pathophysiology and may be a promising biomarker in COVID-19.

Trial registration number

NCT04314232.
Therapeutic enzymes as non-conventional targets in cardiovascular impairments: A comprehensive review
Authors: Kumar Gaurav , Saini Manisha , Kundu Suman
Published: December 2021

Over the last few decades, substantial progress has been made towards the understanding of cardiovascular diseases. In-depth mechanistic insights have also provided opportunities to explore novel therapeutic targets and to discover new treatment regimens. Therapeutic enzymes are examples of such opportunities. The enzymes protect against a variety of cardiovascular diseases, however, even minor malfunctioning of these enzymes may lead to deleterious outcomes. Owing to their great versatility, the inhibition and activation of these enzymes are key regulatory approaches to counter the onset and progression of several cardiovascular impairments. While cardiovascular remedies are already available in excess and are efficacious, a comprehensive description of novel therapeutic enzymes to combat cardiovascular diseases would still be of great benefit. In the light of this, the regulation of functional activities of these enzymes also opens a new avenue for the treatment approaches to be employed. This review describes the importance of non-conventional enzymes such as nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX), phosphodiesterase (PDE), arginase, superoxide dismutase (SOD), thioredoxin reductase (TXNRD) and selenoprotein T (SELENOT), cytochrome b5 reductase 3 (CYB5R3), epoxide hydrolase (EHs), xanthine oxidoreductase (XOR), matrix metalloprotease (MMPs), and dopamine beta hydroxylase (DBH), as potential candidates in several cardiovascular disorders while highlighting some of the recently targeted therapeutic enzymes in cardiovascular diseases. We also discuss the role of intrinsic antioxidant defense system involved in cardioprotection followed by addressing some of the clinical investigations considering the use of antioxidant as a preferred therapy of cardiovascular complications.
The impact of sources and sinks on the dynamics of homogeneous and heterogeneous boolean networks
Authors: Agostini Luca
Published: December 2021

Random Boolean networks, originally introduced as simplified models for the genetic regulatory networks, are abstract models widely applied for the study of the dynamical behaviors of self-organizing complex systems. In these networks, connectivity and the bias of the Boolean functions are the most important factors that can determine the behavioral regime of the systems. On the other hand, it has been found that topology and some structural elements of the networks such as the reciprocity, self-loops and source nodes, can have relevant effects on the dynamical properties of critical Boolean networks. In this paper, we study the impact of source and sink nodes on the dynamics of homogeneous and heterogeneous Boolean networks. Our research shows that an increase of the source nodes causes an exponentially growing of the different behaviors that the system can exhibit regardless of the network topology, while the amount of order seems to undergo modifications depending on the topology of the system. Indeed, with the increase of the source nodes the orderliness of the heterogeneous networks also increases, whereas it diminishes in the homogeneous ones. On the other hand, although the sink nodes seem not to have effects on the dynamic of the homogeneous networks, for the heterogeneous ones we have found that an increase of the sinks gives rise to an increasing of the order, although the different potential behaviors of the system remains approximately the same.
Chinese Medicine for Coronavirus Disease 2019 (COVID-19): A GRADE-Assessed Systematic Review and Meta-Analysis
Authors: Guo Jianbo , Qin Zongshi , Lau Ngai Chung , Fong Tung Leong , Meng Wei , Zhang Zhang-Jin , Luo Yi , Wong Vivian Chi-Woon Taam , Feng Yibin , Chen Haiyong
Published: December 2021

Coronavirus disease 2019 (COVID-19) has caused enormous public health and socioeconomic burden globally. This study aims to evaluate the efficacy and safety of Chinese medicine (CM) against COVID-19. Eleven databases were searched on April 30, 2021, and 52 studies were included. The RoB 2.0, ROBINS-I, and GRADE tools were employed to assess the risks and evidence grades. The findings with moderate certainty in GRADE showed that compared with routine treatment (RT), Lianhua Qingwen granules (LHQW) adjunctive to RT showed significantly improved efficacy rate (relative risk (RR) = 1.19, 95% confidence interval (CI): [1.09, 1.31]), febrile score (standard mean difference (SMD) = −1.21, 95% CI: [−1.43, −0.99]), and computerized tomography (CT) lung images (RR = 1.23, 95% CI: [1.10, 1.38]); Qingfei Paidu decoction (QFPD) plus RT significantly shortened the length of hospital stay (SMD = −1.83, 95% CI: [−2.18, −1.48]); Feiyan Yihao formula (FYYH) plus RT significantly improved the clinical efficacy rate (RR = 1.07, 95% CI: [1, 1.15]), febrile time (SMD = −0.02, 95% CI: [−0.23, 0.19]), and time to negative PCR test for COVID-19 (SMD = −0.72, 95% CI: [−0.94, −0.51]). Adjunctive effects of CM with lower certainty of evidence were found, including the improvements of symptoms, laboratory findings, and mortality. No or mild adverse events were observed in most of the studies. In conclusion, the current evidence indicates that CM formulae, particularly LHQW, QFPD, and FYYH, have adjunctive effects on the standard treatment of COVID-19.
Julia Sets and Their Control in a Three-Dimensional Discrete Fractional-Order Financial Model
Authors: Zhao Zhongyuan , Zhang Yongping
Published: December 2021

It is of great significance to study the three-dimensional financial system model based on the discrete fractional-order theory. In this paper, the Julia set of the three-dimensional discrete fractional-order financial model is identified to show its fractal characteristics. The sizes of the Julia sets need to be changed in some situations, so it is necessary to achieve control of the Julia sets. In combination with the characteristics of the model, two different controllers based on the fixed point are designed, and the control of the three-dimensional Julia sets is realized by adding the controllers into the model in different ways. Finally, the simulation graphs show that the controllers can effectively control the fractal behaviors.
On Extremal Positive Maps of Three-Dimensional Matrix Algebra
Authors: Ługiewicz Piotr , Olkiewicz Robert
Published: December 2021

A class of bistochastic maps of three-dimensional matrix algebra which preserves a one-dimensional projector is studied.
On the Representation of Boolean and Real Functions as Hamiltonians for Quantum Computing
Authors: Hadfield Stuart
Published: December 2021

Mapping functions on bits to Hamiltonians acting on qubits has many applications in quantum computing. In particular, Hamiltonians representing Boolean functions are required for applications of quantum annealing or the quantum approximate optimization algorithm to combinatorial optimization problems. We show how such functions are naturally represented by Hamiltonians given as sums of Pauli
Z
operators (Ising spin operators) with the terms of the sum corresponding to the function’s Fourier expansion. For many classes of Boolean functions which are given by a compact description, such as a Boolean formula in conjunctive normal form that gives an instance of the satisfiability problem, it is #P-hard to compute its Hamiltonian representation, i.e., as hard as computing its number of satisfying assignments. On the other hand, no such difficulty exists generally for constructing Hamiltonians representing a real function such as a sum of local Boolean clauses each acting on a fixed number of bits as is common in constraint satisfaction problems. We show composition rules for explicitly constructing Hamiltonians representing a wide variety of Boolean and real functions by combining Hamiltonians representing simpler clauses as building blocks, which are particularly suitable for direct implementation as classical software. We further apply our results to the construction of controlled-unitary operators, and to the special case of operators that compute function values in an ancilla qubit register. Finally, we outline several additional applications and extensions of our results to quantum algorithms for optimization. A goal of this work is to provide a
design toolkit for quantum optimization
which may be utilized by experts and practitioners alike in the construction and analysis of new quantum algorithms, and at the same time to provide a unified framework for the various constructions appearing in the literature.
Open Problems Related to Quantum Query Complexity
Authors: Aaronson Scott
Published: December 2021

I offer a case that quantum query complexity still has loads of enticing and fundamental open problems—from relativized
QMA
versus
QCMA
and
BQP
versus
IP
, to time/space tradeoffs for collision and element distinctness, to polynomial degree versus quantum query complexity for partial functions, to the Unitary Synthesis Problem and more.
(100) Plane β-Ga2O3 Flake Based Field Effect Transistor and Its Hydrogen Response
Authors: Kim Man-Kyung , Kim Yukyung , Bae Jinho , Kim Jihyun , Baik Kwang Hyeon , Jang Soohwan
Published: December 2021

2-dimensional (100) plane β phase Ga2O3 (β-Ga2O3) flake based field effect transistor (FET) was fabricated, and its electrical characteristics was analyzed. The (100) plane β-Ga2O3 flake was mechanically exfoliated from the side wall of

2
¯

01

plane β-Ga2O3 bulk substrate. The minimum thickness of 57.3 nm was obtained for the very thin (100) plane β-Ga2O3 channel layer of the FET using inductively coupled plasma etching with BCl3/N2 chemistry. The current-voltage characteristics of the FET with various β-Ga2O3 channel thickness was investigated. The dependence of the channel thickness on the drain current density, threshold voltage, transconductance, and field effect mobility was studied. The hydrogen response of the (100) plane Ga2O3 flake based FET with catalytic Pt gate surface was measured in the range of 10–500 ppm at 400 °C, and modeled with a dissociative Langmuir isotherm. The device showed a reliable responsivity to the different concentration of hydrogen exposure, and the responsivity of 25.02% was observed for the 500 ppm hydrogen at 400 °C.
A Review on Utilization Routes of the Leather Industry Biomass
Authors: Ayele Million , Limeneh Derseh Yilie , Tesfaye Tamrat , Mengie Wassie , Abuhay Amare , Haile Adane , Gebino Gemeda
Published: December 2021

The use of biomass to produce bioenergy and biomaterials is considered a sustainable alternative to depleting fossil fuel resources. The world tanneries consume 8–9 MT of skin and hide every year producing 1.4 MT of solid waste. Most of the solid biomass generated from tanneries is disposed of as waste in the environment using either landfilling or thermal incineration. Disposal of this waste into the environment affects the ecosystem, causing bad odor (air pollution) and has an antagonistic impact on the environment. Due to this, European Union legislation bans the landfilling of biomass. This study aims to comprehensively review the possible valorization routes of leather processing industry biomass into high‐value biomaterials. Leather biomass (trimmings, shaving, splitting, and buffing dust) mainly contain 30%–35% collagen protein, which is produced by acid or alkali hydrolysis. The biopolymers obtained from leather industry biomass can be utilized in the production of several high‐value materials. In addition, leather processing industry biomass also contains fat, which can be converted into a bio‐surfactant, and other useful biomaterials. Keratin protein can also be extracted from the hair waste of hides and skins. The increased demand for biomaterials makes the using of leather industry biomass very attractive. From this study, it can be concluded that the conversions of leather processing industry waste to valuable biomaterial can protect the environment, generate additional income for leather industries, and pave way for sustainable and renewable biomaterials production.
Applied Mathematical Modelling and Heat Transport Investigation in Hybrid Nanofluids under the Impact of Thermal Radiation: Numerical Analysis
Authors: Khan Umar , Ullah Basharat , Khan Wahid , Adnan  , Khan Ilyas , Fayz-Al-Asad Md.
Published: December 2021

Nanofluids are solid-liquid mixtures that have a dispersion of nanometer-sized particles in conventional base fluids. The flow and heat transmission in an unstable mixed convection boundary layer are affected by the thermal conductivity and dynamic viscosity uncertainty of a nanofluid over a stretching vertical surface. There is time-dependent stretching velocity and surface temperature instability in both the flow and temperature fields. It is possible to scale the governing partial differential equations and then solve them using ordinary differential equations. Cu and Al2O3 nanofluids based on water are among the possibilities being investigated. An extensive discussion has been done on relevant parameters such as the unsteadiness parameter and the mixed convection parameter's effect on solid volume fraction of nanoparticles. In addition, alternative nanofluid models based on distinct thermal conductivity and dynamic viscosity formulas are examined for their flow and heat transmission properties. On the basis of the comparison, it is concluded that the results are spot on for steady state flow.
Efficacy of Praziquantel for the Treatment of Human Schistosomiasis in Ethiopia: A Systematic Review and Meta-Analysis
Authors: Hailegebriel Tamirat , Nibret Endalkachew , Munshea Abaineh
Published: December 2021

Background. Schistosomiasis is one of the neglected tropical diseases causing a serious human health problem in Ethiopia. Praziquantel is the only drug that has been used for the treatment of human schistosomiasis in the country. In line with this, the efficacy of praziquantel has been evaluated in a few interventional studies in the country, but there is a lack in systematically gathered and analyzed information for policymakers. The aim of this systematic review and meta-analysis was to provide a summary of the efficacy of praziquantel for the treatment of human schistosomiasis in Ethiopia. Methods. We conducted a literature search from ScienceDirect, PubMed/Medlin, and Google Scholar databases. A total of 140 articles published in English from 1980 to June 2021 were accessed and 15 of them were eligible for this meta-analysis. The meta-analysis was conducted using Stata 14 software, “metan command.” The heterogeneities among studies were evaluated using I2 test. Results. A total of 140 articles were reviewed, but only 15 of them fulfilled the inclusion criteria. The polled cure rate of 40 mg/kg praziquantel was 89.2% (95% CI: 85.4–93.1) and 93.6% (95% CI: 80.6–106) among Schistosoma mansoni and S. haematobium, respectively. Similarly, the mean egg reduction rates of 40 mg/kg praziquantel were 90.2% and 85% among S. mansoni and S. haematobium infected subjects, respectively. The common adverse events observed after receiving praziquantel include abdominal pain, vomiting, headache, diarrhea, and bloody stool. Conclusion. This systematic review and meta-analysis has indicated that praziquantel is still an appropriate drug for the treatment of human schistosomiasis in Ethiopia.
GTF: An Adaptive Network Anomaly Detection Method at the Network Edge
Authors: Li Renjie , Zhou Zhou , Liu Xuan , Li Da , Yang Wei , Li Shu , Liu Qingyun
Published: December 2021

Network Anomaly Detection (NAD) has become the foundation for network management and security due to the rapid development and adoption of edge computing technologies. There are two main characteristics of NAD tasks: tabular input data and imbalanced classes. Tabular input data format means NAD tasks take both sparse categorical features and dense numerical features as input. In order to achieve good performance, the detection model needs to handle both types of features efficiently. Among all widely used models, Gradient Boosting Decision Tree (GBDT) and Neural Network (NN) are the two most popular ones. However, each method has its limitation: GBDT is inefficient when dealing with sparse categorical features, while NN cannot yield satisfactory performance for dense numerical features. Imbalanced classes may downgrade the classifier’s performance and cause biased results towards the majority classes, often neglected by many exiting NAD studies. Most of the existing solutions addressing imbalance suffer from poor performance, high computational consumption, or loss of vital information under such a scenario. In this paper, we propose an adaptive ensemble-based method, named GTF, which combines TabTransformer and GBDT to leverage categorical and numerical features effectively and introduces Focal Loss to mitigate the imbalance classification. Our comprehensive experiments on two public datasets demonstrate that GTF can outperform other well-known methods in both multiclass and binary cases. Our implementation also shows that GTF has limited complexity, making it be a good candidate for deployment at the network edge.
Experimental Research on Narrowband Interference Suppression of GNSS Signals
Authors: Wang Bin , Sun Yanjing , Liu Yang , Zhang Yuzhi , Li Song
Published: December 2021

The navigation satellites are running at a high altitude of 20000 km from the ground, and the satellite signals arriving at the ground are very weak, such as the C/A code on the L1 band, which is only ‐160 dBW. In complex urban environments, especially when there is an occlusion, the signal power will be even lower. Low power causes the signal to be easily disturbed, where suppressed interference is the most common method of interference. The purpose of this paper is to experiment with the BPSK and BOC signal system to do the narrowband suppression of interference analysis and set up the actual test environment, based on the commonly used LMS algorithm for the two systems of narrowband interference performance contrast analysis, and throughout the simulation, it can be seen that the two improved algorithms can effectively suppress narrowband interference, thus improving the anti‐interference performance of satellite navigation receiver.
Investigation on Friction Stir Weldability Characteristics of AA7075‐T651 and AA6061‐T6 Based Nanocomposites
Authors: Madhusudan M. , Shanmuganatan S. P. , Shridhar Kurse , John Jacob , Krishnamurthy R. , Sasikumar Bashyam
Published: December 2021

Friction stir welding (FSW) is an emerging solid‐state process and alternative to fusion welding, wherein frictional heat is generated between a nonconsumable rotating steel tool and the work substrate. The present study focuses on the influence of the operating attributes like tool pin contact geometry, welding speed, and tool rotational speed on dissimilar aluminum matrix nanocomposites. AA6061‐T6 and AA7075‐T651 aluminum alloy plates were joined via double‐pass FSW with the inclusion of 5 vol. % of nanoscale h‐BN particles. Welding was performed with four rotational speeds (600, 800, 900, and 1000 rpm), three traversing speeds (30, 40, and 60 mm/min), and three distinct tool pin geometry (cylindrical, threaded cylindrical, and square), respectively. Besides, unreinforced and reinforced weldments were analyzed for mechanical properties like tensile strength and microhardness. Microstructural characterization was also carried out using FESEM and XRD techniques. The findings concluded that the reinforced samples welded using a cylindrical tool and double‐pass strategy showcased homogenous distribution of nanoparticles with grain refinement, thereby exhibiting improved strength and hardness.
A Computational Offloading Method for Edge Server Computing and Resource Allocation Management
Authors: Al-Razgan Muna , Alfakih Taha , Hassan Mohammad Mehedi
Published: December 2021

The emerging technology of mobile cloud is introduced to overcome the constraints of mobile devices. We can achieve that by offloading resource intensive applications to remote cloud-based data centers. For the remote computing solution, mobile devices (MDs) experience higher response time and delay of the network, which negatively affects the real-time mobile user applications. In this study, we proposed a model to evaluate the efficiency of the close-end network computation offloading in MEC. This model helps in choosing the adjacent edge server from the surrounding edge servers. This helps to minimize the latency and increase the response time. To do so, we use a decision rule based Heuristic Virtual Value (HVV). The HVV is a mapping function based on the features of the edge server like the workload and performance. Furthermore, we propose availability of a virtual machine resource algorithm (AVM) based on the availability of VM in edge cloud servers for efficient resource allocation and task scheduling. The results of experiment simulation show that the proposed model can meet the response time requirements of different real-time services, improve the performance, and minimize the consumption of MD energy and the resource utilization.
Embedded System Intelligent Platform Design Based on Digital Multimedia Artistic Design
Authors: Ren Xinguang , Cui Yongmin
Published: December 2021

With the ever‐changing times, technological progress, media transformation, and innovation, the soil for the growth of digital media art has been cultivated. The rapid development of the mobile Internet combines multimedia communications such as pictures, text, audio, video, and data, which greatly enriches people’s life experience. Embedded systems have strong processing capabilities, small size, and convenient use. In recent years, they have become the mainstream of multimedia research. Therefore, this paper proposes a research on the design of an embedded system intelligent platform based on digital multimedia artistic design. This paper adopts the literature research method to study the development and evolution of digital multimedia and the characteristics and applications of embedded systems and other related theoretical research and design an embedded system intelligent platform based on the artistic design of digital multimedia, from software and hardware design and application The platform design research is carried out in three aspects of the program, and the effect comparison of system’s scheduling test, real‐time test, peak signal‐to‐noise ratio test, and digital multimedia art design is analyzed. The experimental results show that when the pixel values are the same (both are 6), the signal‐to‐noise ratio of this method reaches 48.5, which is higher than the output value of other method platforms, and the system setting performance is better.
Evaluation of the Effects of the Belt and Road Initiative on the Unified Economic and Environmental Efficiency of Transportation Infrastructure in China Based on Range‐Adjusted Measure Model and Difference in Difference Model
Authors: Wang Yijiao
Published: December 2021

The Belt and Road Initiative has brought new opportunities for countries along the routes to develop their transportation infrastructure. Through large‐scale transportation infrastructure construction, these countries enhanced the Belt and Road cooperation with each other, which further facilitates the rapid development of their own economy, but whether this can promote the sustainable development of their own environment, relevant research is still lacking. In this paper, China is taken as the study subject to evaluate the comprehensive effects that the Belt and Road Initiative exerts on the economy and environment through improving transportation infrastructure. In the study, RAM indicators were first established to measure the unified economic and environmental efficiency of transportation infrastructure, a DID model was then built to study the effects of the Initiative on the unified efficiency, and mediation models were finally created to discuss the ways in which the Belt and Road Initiative can improve the unified economic and environmental efficiency of transportation infrastructure through transformation and upgrade of industrial structure. The study result shows that the Belt and Road Initiative can significantly promote the improvement of the unified economic and environmental efficiency of the national transportation infrastructure, but the result is regionally heterogeneous. The Initiative has positive effects in improving the unified efficiency in eastern region but has no effect in the central and western regions. Although the Initiative can significantly enhance the efficiency through transforming and upgrading the industrial structure, the industrial structure rationalization plays a primary positive role. This paper provides the empirical evidences to evaluate the implementation effects of the Initiative in the transportation infrastructure sector and verifies that countries along the routes can achieve sustainable development through large‐scale transportation infrastructure construction under the Belt and Road Initiative.
Construction Safety Risk Assessment of Large-Sized Deep Drainage Tunnel Projects
Authors: Hu Kai , Wang Junwu , Wu Han
Published: December 2021

Frequent extreme climate events and rapid global urbanization have amplified the occurrence of accidents such as waterlogging or the overflow of pollution in big cities. This has increased the application scenarios of large-sized deep drainage tunnel projects (LSDDTPs). The scientific and accurate evaluation of the construction safety risks of LSDDTP can effectively reduce the corresponding economic losses and casualties. In this paper, we employed the hierarchical holographic model to construct the safety risk list of LSDDTPs in terms of the risk source and construction unit. Based on social network analysis, we then screened key indicators and calculated the weights of all secondary indicators from the correlation between risk factors. We subsequently developed a construction safety risk assessment model of LSDDTPs based on the matter-element extension method. The Donghu Deep Tunnel Project in Wuhan, China, was selected as a case study for the proposed method. The results of empirical research demonstrated that eight indicators (e.g., failure to effectively detect the change of the surrounding environment of the tunnel project) were key factors affecting the construction safety risk of IV, which is within the acceptable risk level. Our proposed model outperformed other methods (the fuzzy comprehensive evaluation, analytic hierarchy process, entropy weight method, and comprehensive weight method) in terms of scientific validity and research advancements.
Research on English Online Test Platform Based on Real-Time Web Communication Technology
Authors: Huo Junyan , Wang Chunxia
Published: December 2021

Due to the multiattribute and multi-related problems of the target English test platform, the efficiency of the platform is low. In order to solve the problem of insufficient control of the difficulty of the test questions in the process of English test paper generation, this paper designs an English test platform based on real-time network communication technology. The English test platform designed in this paper includes three modules: user management module, question bank management module, and test paper management module. Among them, in the test paper management module, we extract English test questions according to the test paper generation strategy, then use real-time web communication technology according to the test paper generation target, and, through effective update of pheromone, solve the problem of high test question repetition rate in automatic test paper generation and design the network. The self-learning platform and English test platform modules have completed the design of the English test platform based on real-time network communication technology. The experimental results show that the designed English test platform has a high success rate, quick test paper generation time, and good application value.
A Study of Supplier Selection Method Based on SVM for Weighting Expert Evaluation
Authors: Zhao Li , Qi Wenjing , Zhu Meihong
Published: December 2021

How to choose suppliers scientifically is an important part of strategic decision-making management of enterprises. Expert evaluation is subjective and uncontrollable; sometimes, there exists biased evaluation, which will lead to controversial or unfair results in supplier selection. To tackle this problem, this paper proposes a novel method that employs machine learning to learn the credibility of expert from historical data, which is converted to weights in evaluation process. We first use the Support Vector Machine (SVM) classifier to classify the historical evaluation data of experts and calculate the experts’ evaluation credibility, then determine the weights of the evaluation experts, finally assemble the weighted evaluation results, and get a preference order of choosing suppliers. The main contribution of this method is that it overcomes the shortcomings of multiple conversions and large loss on evaluation information, maintains the initial evaluation information to the maximum extent, and improves the credibility of evaluation results and the fairness and scientificity of supplier selection. The results show that it is feasible to classify the past evaluation data of the evaluation experts by the SVM classification model, and the expert weights determined on the basis of the evaluation credibility of experts are adjustable.
An Improved 2D U-Net Model Integrated Squeeze-and-Excitation Layer for Prostate Cancer Segmentation
Authors: Liu Bingshuai , Zheng Jiawei , Zhang Hongwei , Chen Peijie , Li Shipeng , Wen Yuexian
Published: December 2021

In this paper, we proposed an improved 2D U-Net model integrated squeeze-and-excitation layer for prostate cancer segmentation. The proposed model combined a more complex 2D U-Net model and squeeze-and-excitation technique. The model consisted of an encoder stage and a decoder stage. The encoder stage aims to extract features of the input, which contains CONV blocks, SE layers, and max-pooling layers for improving the feature extraction capability of the model. The decoder aims to map the extracted features to the original image with CONV blocks, SE layers, and upsampling layers. The SE layer is implemented to learn more global and local features. Experiments on the public dataset PROMISE12 have demonstrated that the proposed model could achieve state-of-the-art segmentation performance compared with other traditional methods.
Allocation Optimization of Multi‐Axis Suspension Dynamic Parameter for Tracked Vehicle
Authors: Ling Qihui , Dai Juchuan , He Xingyun , Chen Shengzhao , Chen Zhewu
Published: December 2021

The dynamic parameter allocation of the suspension system has an important influence on the comprehensive driving performance of the tracked vehicle. Usually, the allocation of suspension parameters is based on a single performance index, which has the disadvantage of not being able to achieve multi‐performance optimization. Therefore, a novel optimization method using multi‐performance index‐oriented is presented. Firstly, considering the vertical vibration excitation caused by road roughness, the input (excitation) model of road roughness is embedded to establish the parametric dynamic model of the tracked vehicle. Then, the evaluation index and its quantitative algorithm, which reflect the multi‐aspect performance of the suspension system, are proposed. Moreover, the parameter allocation objective function based on multi‐index information fusion is designed. Finally, two allocation optimization methods are presented to solve the parameter allocation, i.e., equal weight allocation and expert knowledge‐based weight allocation. By comparing the results obtained by the two methods, it is found that the performance of the suspension system can be improved effectively by optimizing the parameters of suspension stiffness and damping. Furthermore, the optimization of weight allocation based on expert knowledge is more effective. These provide a better knowledge reference for suspension system design.
A Novel Self-Positioning Based on Feature Map Creation and Laser Location Method for RBPF-SLAM
Authors: Shen Yubao , Jiao Zhipeng
Published: December 2021

Aiming at the high computational complexity of the traditional Rao-Blackwellized Particle Filtering (RBPF) method for simultaneous localization and Mapping (SLAM), an optimization method of RBPF-SLAM system is proposed, which is based on lidar and least square line segment feature extraction as well as raster, reliability mapping continuity. Validation test results show that less storage in constructing a map with this method is occupied, and the computational complexity is significantly reduced. The effect of noise data on feature data extraction results is effectively avoided. It also solves the problem of error accumulation caused by noninteger grid size movement of unmanned vehicle in time update stage based on Markov positioning scheme. The improved RBPF-SLAM method can enable the unmanned vehicle to construct raster map in real time, and the efficiency and accuracy of map construction are significantly improved.
Evaluación de docentes en programas de posgrado
Authors: Olascoaga Ana Cecilia , Ticse Aguirre Ray , Caballero López José
Published: December 2021

Los profesores son parte fundamental de una escuela de medicina. A nivel de la residencia médica, la evaluación de la docencia clínica es una estrategia de mejoramiento de la educación que permite identificar las deficiencias que existen para superarlas mediante capacitación, así como reconocer las buenas prácticas docentes. Los modelos de evaluación docente utilizados en distintas facultades de medicina comprenden: la evaluación por pares, la autoevaluación, la evaluación basada en la opinión de los estudiantes y el portafolio docente. Con el fin de mejorar la calidad de la enseñanza y la calidad de los programas formativos en la residencia médica es necesario contar instrumentos de evaluación válidos, confiables, factibles y que cuenten con la aceptación de los profesores y residentes. Esta evaluación debe ser devuelta al docente mediante un proceso de retroalimentación efectiva y conectarse a un plan de desarrollo docente, de capacitación y de reconocimiento, enmarcado dentro de la carrera profesional. El sistema de evaluación y desarrollo docente debe partir de la institución universitaria responsable de la formación del médico residente.