bluuebunny/crossref_metadata_2025 huggingface dataset:
Temporally modulated one-dimensional leaky-wave holograms
Authors: Amini Amrollah , Oraizi Homayoon
Published: May 2022

Spatio-temporally modulated impedance surfaces can be good candidates for generation of radiating waves with arbitrary eigenstates by breaking momentum and energy conservations. Here, we present a theoretical framework based on the holographic technique and generalized Floquet-wave expansion to analyze spatio-temporally modulated impedance surfaces. The holographic technique estimates the required impedance distribution to achieve the desired momentum. Injecting temporal modulation deviates the eigenvalues and changes the radiation frequency. Using the proposed analytical model, the eigenvalues can be calculated accurately in the presence of space and time modulations. Consequently, it is possible to predict the propagation mechanism of bounded and radiation states. It has been shown that, imposition of temporal modulation causes the Doppler-shift effect and nonreciprocal responses in the hologram. By plotting the antenna dispersion diagram, and observing the asymmetric displacement of dispersion curve due to temporal modulation, the system nonreciprocity can be verified. The beam scanning properties of these structures have also been investigated.
Genomic, morphological, and biochemical analyses of a multi-metal resistant but multi-drug susceptible strain of Bordetella petrii from hospital soil
Authors: Halder Urmi , Biswas Raju , Kabiraj Ashutosh , Deora Rajendar , Let Moitri , Roy Rajendra Kr , Chitikineni Annapurna , Majhi Krishnendu , Sarkar Shrabana , Dutta Bhramar , Laha Anubhab , Datta Arunava , Khan Dibyendu , Varshney Rajeev K. , Saha Dipnarayan , Chattopadhyay Saswati , Bandopadhyay Rajib
Published: May 2022

Contamination of soil by antibiotics and heavy metals originating from hospital facilities has emerged as a major cause for the development of resistant microbes. We collected soil samples surrounding a hospital effluent and measured the resistance of bacterial isolates against multiple antibiotics and heavy metals. One strain BMCSI 3 was found to be sensitive to all tested antibiotics. However, it was resistant to many heavy metals and metalloids like cadmium, chromium, copper, mercury, arsenic, and others. This strain was motile and potentially spore-forming. Whole-genome shotgun assembly of BMCSI 3 produced 4.95 Mb genome with 4,638 protein-coding genes. The taxonomic and phylogenetic analysis revealed it, to be a Bordetella petrii strain. Multiple genomic islands carrying mobile genetic elements; coding for heavy metal resistant genes, response regulators or transcription factors, transporters, and multi-drug efflux pumps were identified from the genome. A comparative genomic analysis of BMCSI 3 with annotated genomes of other free-living B. petrii revealed the presence of multiple transposable elements and several genes involved in stress response and metabolism. This study provides insights into how genomic reorganization and plasticity results in evolution of heavy metals resistance by acquiring genes from its natural environment.
Controlling resistive switching behavior in the solution processed SiO2-x device by the insertion of TiO2 nanoparticles
Authors: Kwon Sera , Kim Min-Jung , Lim Dong-Hyeok , Jeong Kwangsik , Chung Kwun-Bum
Published: May 2022

The resistive switching behavior of the solution processed SiOx device was investigated by inserting TiO2 nanoparticles (NPs). Compared to the pristine SiOx device, the TiO2 NPs inserted SiOx (SiOx@TiO2 NPs) device achieves outstanding switching characteristics, namely a higher ratio of SET/RESET, lower operating voltages, improved cycle-to-cycle variability, faster switching speed, and multiple-RESET states. Density functional theory calculation (DFT) and circuit breaker simulation (CB) were used to detail the origin of the outstanding switching characteristic of the SiOx@TiO2 NPs. The improvement in resistive switching is mainly based on the difference in formation/rupture of the conductive path in the SiO2 and SiO2@TiO2 NPs devices. In particular, the reduction of resistance and lower switching voltage of TiO2 NPs control the formation and rupture of the conductive path to achieve more abrupt switching between SET/RESET with higher on/off ratio. This method of combined DFT calculation and CB offers a promising approach for high-performance non-volatile memory applications.
Functionalized electrospun nanofibers for high efficiency removal of particulate matter
Authors: Senthil Rethinam , Sumathi Vijayan , Tamilselvi Alagumuthu , Kavukcu Serdar Batıkan , Aruni A. Wilson
Published: May 2022

In recent years, introducing electrospun airfilters to enhance the removal of PM2.5 and PM10–2.5 has received much interest. In this study, a novel poly-(vinyl) alcohol (PVA)/carbon nanoparticle (CNP)/tea leaf extract (TLE), functionalized nanofibrous air filter (FNA) was fabricated using an electrospinning method. Novelty of the unique work in the blending of CNP and TLE, first of its kind, for the preparation of FNA. Polysaccharide crosslinked FNA has a carbon complex with two monosaccharide units to produce the intrinsic properties of the PM2.5 and PM10–2.5 removal efficiency. The FNA had promising traits of UV protection. The prepared FNA was characterized using physicochemical, mechanical, antimicrobial activity, etc., in addition to its PM2.5 and PM10–2.5 removal efficiency. Pore size and distribution study using the capillary flow porometry method has proved the structure of FNA. FNA exhibited excellent low pressure drop (110 Pa), which are promising characteristics for air purification. FNA from PVA: CNP: TLE exhibited high PM2.5 and PM10–2.5 removal efficiencies of 99.25% and 99.29%, respectively. Hence, the study proved.
Geographic and socioeconomic inequalities in the survival of children under-five in Nigeria
Authors: Okoli Chijioke Ifeanyi , Hajizadeh Mohammad , Rahman Mohammad Mafizur , Khanam Rasheda
Published: May 2022

Despite a substantial decline in child mortality globally, the high rate of under-five mortality in Nigeria is still one of the main public health concerns. This study investigates inequalities in geographic and socioeconomic factors influencing survival time of children under-five in Nigeria. This is a retrospective cross-sectional quantitative study design that used the latest Nigeria Demographic Health Survey (2018). Kaplan–Meier survival estimates, Log-rank test statistics, and the Cox proportional hazards were used to assess the geographic and socioeconomic differences in the survival of children under-five in Nigeria. The Kaplan–Meier survival estimates show most under-five mortality occur within 12 months after birth with the poorest families most at risk of under-five mortality while the richest families are the least affected across the geographic zones and household wealth index quintiles. The Cox proportional hazard regression model results indicate that children born to fathers with no formal education (HR: 1.360; 95% CI 1.133–1.631), primary education (HR: 1.279; 95% CI 1.056–1.550) and secondary education (HR: 1.204; 95% CI 1.020–1.421) had higher risk of under-five mortality compared to children born to fathers with tertiary education. Moreover, under-five mortality was higher in children born to mothers’ age ≤ 19 at first birth (HR: 1.144; 95% CI 1.041–1.258). Of the six geopolitical zones, children born to mothers living in the North-West region of Nigeria had 63.4% (HR 1.634; 95% CI 1.238–2.156) higher risk of under-five mortality than children born to mothers in the South West region of Nigeria. There is a need to focus intervention on the critical survival time of 12 months after birth for the under-five mortality reduction. Increased formal education and target interventions in geopolitical zones especially the North West, North East and North Central are vital towards achieving reduction of under-five mortality in Nigeria.
Absence of increased genomic variants in the cyanobacterium Chroococcidiopsis exposed to Mars-like conditions outside the space station
Authors: Napoli Alessandro , Micheletti Diego , Pindo Massimo , Larger Simone , Cestaro Alessandro , de Vera Jean-Pierre , Billi Daniela
Published: May 2022

Despite the increasing interest in using microbial-based technologies to support human space exploration, many unknowns remain not only on bioprocesses but also on microbial survivability and genetic stability under non-Earth conditions. Here the desert cyanobacterium Chroococcidiopsis sp. CCMEE 029 was investigated for robustness of the repair capability of DNA lesions accumulated under Mars-like conditions (UV radiation and atmosphere) simulated in low Earth orbit using the EXPOSE-R2 facility installed outside the International Space Station. Genomic alterations were determined in a space-derivate of Chroococcidiopsis sp. CCMEE 029 obtained upon reactivation on Earth of the space-exposed cells. Comparative analysis of whole-genome sequences showed no increased variant numbers in the space-derivate compared to triplicates of the reference strain maintained on the ground. This result advanced cyanobacteria-based technologies to support human space exploration.
Influence of the extent of hydrophobicity on water organization and dynamics on 2D graphene oxide surfaces
Authors: M. Rajasekaran , Ayappa K. Ganapathy
Published: May 2022

Water adsorption on graphene oxide surfaces plays an important role in determining hydrogen bond characteristics important for 2D water and proton transport applications.
Iridoid glycoside isolated from Wendlandia glabrata and the role of its enriched fraction in regulating AMPK/PEPCK/G6Pase signaling pathway of hepatic gluconeogenesis
Authors: Sarma Pranamika , Bharadwaj Simanta , Swargiary Deepsikha , Ahmed Semim Akhtar , Sheikh Yunus , Barge Sagar Ramrao , Manna Prasenjit , Talukdar Narayan Chandra , Bora Jayanta , Borah Jagat Chandra
Published: May 2022

Phytochemical investigation of W. glabrata and antihyperglycemic potential of isolated novel iridoid glycoside enriched fraction in CC1 hepatocytes and STZ-induced diabetic mice.
Current status of secondary metabolite pathways linked to their related biosynthetic gene clusters in Aspergillus section Nigri
Authors: Wang Xinhui , Jarmusch Scott A. , Frisvad Jens C. , Larsen Thomas O.
Published: May 2022

Aspergilli are biosynthetically ‘talented’ micro-organisms and therefore the natural products community has continually been interested in the wealth of biosynthetic gene clusters (BGCs) encoding numerous secondary metabolites related to these fungi.
Structure, properties of gossypol and its derivatives—from physiological activities to drug discovery and drug design
Authors: Liu Yanxia , Wang Lulu , Zhao Lin , Zhang Yagang
Published: May 2022

Gossypol is a polyphenolic compound isolated from cottonseed.
Aromaticity-enhanced reactivity of geminal frustrated Lewis pairs
Authors: Cabrera-Trujillo Jorge Juan , Fernández Israel
Published: May 2022

The presence of a cyclopropenimine moiety as the Lewis base partner in geminal frustrated Lewis pairs greatly enhances the reactivity of the system towards the activation of small molecules.
Structurally directed thienylenevinylene self-assembly for improved charge carrier mobility: 2D sheets vs. 1D fibers
Authors: Ghosh Samrat , Prasanthkumar Seelam , Das Satyajit , Saeki Akinori , Seki Shu , Ajayaghosh Ayyappanpillai
Published: May 2022

Structural direction of hydrogen-bonded thienylenevinylenes reveals that self-assembled to 1D structures exhibit enhanced photoconductivity and charge carrier mobility when compared to 2D sheets.
Synergetic effect of photocatalysis and peroxymonosulfate activation by MIL-53Fe@TiO2 on efficient degradation of tetracycline hydrochloride under visible light irradiation
Authors: Li Di , Li Hongmiao , Long Mingyang , Bai Xiaojuan , Zhao Qianqian , Wen Qi , Song Fang
Published: May 2022

MIL-53Fe@TiO2 was prepared by a simple solvothermal method. In order to further enhance the degradation efficiency of MIL-53Fe@TiO2, it was used to activate peroxymonosulfate to degrade tetracycline hydrochloride.
Machine-learning-assisted molecular design of phenylnaphthylamine-type antioxidants
Authors: Du Shanda , Wang Xiujuan , Wang Runguo , Lu Ling , Luo Yanlong , You Guohua , Wu Sizhu
Published: May 2022

Efficient phenylnaphthylamine antioxidant molecular structures were constructed through machine learning and molecular simulation combined group contribution methods.
A deeper analysis of the role of synchronicity on the Bell–Evans–Polanyi plot in multibond chemical reactions: a path-dependent reaction force constant
Authors: Barrales-Martínez César , Jaque Pablo
Published: May 2022

The BEP principle is fulfilled at the same degree of (a)synchronicity!
Theoretical insight into the anion vacancy healing process during the oxygen evolution reaction on TaON and Ta3N5
Authors: Liu Taifeng , Zhang Qingyan , Zhao Qianyu
Published: May 2022

Anion vacancies on the outermost surface may be healed during the oxygen evolution reaction (OER).
Selective NMR detection of individual reaction components hyperpolarised by reversible exchange with para-hydrogen
Authors: Norcott Philip L.
Published: May 2022

Using hyperpolarisation from parahydrogen, NMR signals corresponding to the reactant, catalyst or product of a reaction which are normally obscured by low signal-to-noise or signal overlap can be selectively detected and identified.
π-Carbazolyl supported bis(alkyl) complexes of Sc, Y and La for α-olefin polymerization and hydrogenation
Authors: Selikhov Alexander N. , Pechenkina Polina V. , Cherkasov Anton V. , Nelyubina Yulia V. , Kovylina Tatyana A. , Trifonov Alexander A.
Published: May 2022

Rare-earth alkyl complexes [tBu4Carb]La(CH2C6H5)2(THF), [tBu4Carb]Ln(o-NMe2C6H4CH2)2 (Ln = Sc, Y, La), [tBu4Carb]Ln(CH2SiMe3)2(THF) (Ln = Sc, Y) - efficient catalysts for α-olefin polymerization and hydrogenation.
Viable protoplast formation of the coral endosymbiont alga Symbiodinium spp. in a microfluidics platform
Authors: Bashir Faiza , Kovács Sándor , Ábrahám Ágnes , Nagy Krisztina , Ayaydin Ferhan , Valkony-Kelemen Ildikó , Ferenc Györgyi , Galajda Péter , Tóth Szilvia Z. , Sass László , Kós Péter B. , Vass Imre , Szabó Milán
Published: May 2022

Microfluidics-based protoplast isolation, which enabled intracellular uptake of singlet oxygen sensor fluorophore and DNA oligonucleotides in Symbiodinium spp.
Ab initio molecular dynamics simulations on the adsorption of 1-hydroxyethane-1,1-diphosphonic acid on the iron (100) surface
Authors: Zhao Xiaoyang , Liu Bin , Li Jianhua , Nan Junmin
Published: May 2022

Through IRI, Bader charges and ELF analysis, an electrostatic interaction network exists between HEDP and the iron (100) surface, which is responsible for the stability of the adsorption state.
A quantitative description of the voltammetric time series of unclosed electric circuits for detection of differences between different potentiostats/galvanostats
Authors: Nigmatullin Raoul , Alexandrov Vadim , Sidelnikov Artem , Budnikov Herman , Maksyutova Elza , Kvyatkovskaya Adel
Published: May 2022

In this paper, ideal boundary conditions have been created for recording instrument noises and their fluctuations at the level of pico-currents to identify the best “ideal” device using voltammetric time series.
Host–guest sensing towards sodium cyclamate based on a cationic pillar[6]arene reduced graphene nano-composite
Authors: Huang Juncao , Tan Xiaoping , Ran Shuqin , Tao Yuxin , Wu Rui , Li Chaofan , Chen Yuxue , Pan Wen
Published: May 2022

A competitive fluorescence sensing for the detection of sodium cyclamate based on a cationic water-soluble pillar[6]arene graphene nano-composite.
Correction: The ins and outs of transporters at plasma membrane and tonoplast in plant specialized metabolism
Authors: Xu Deyang , Halkier Barbara Ann
Published: May 2022

Correction for ‘The ins and outs of transporters at plasma membrane and tonoplast in plant specialized metabolism’ by Deyang Xu and Barbara Ann Halkier, Nat. Prod. Rep., 2022, https://doi.org/10.1039/d2np00016d.
Practical synthesis of ECH and epoxyquinols A and B from (−)-shikimic acid
Authors: Luo Guiyin , Jia Yuanliang , Hu Yue , Wu Folei , Wang Maolin , Chen Xiaochuan
Published: May 2022

A key stereoselective allylic oxidation, which is achieved by fine tuning the cyclohexene substrate structure and reaction conditions, enables a convenient synthesis of several bioactive epoxyquinoids from (−)-shikimic acid.
Clusters of apoptotic signaling molecule-enriched rafts, CASMERs: membrane platforms for protein assembly in Fas/CD95 signaling and targets in cancer therapy
Authors: Mollinedo Faustino , Gajate Consuelo
Published: May 2022

Mammalian cells show the ability to commit suicide through the activation of death receptors at the cell surface. Death receptors, among which Fas/CD95 is one of their most representative members, lack enzymatic activity, and depend on protein–protein interactions to signal apoptosis. Fas/CD95 death receptor-mediated apoptosis requires the formation of the so-called death-inducing signaling complex (DISC), bringing together Fas/CD95, Fas-associated death domain-containing protein and procaspase-8. In the last two decades, cholesterol-rich lipid raft platforms have emerged as scaffolds where Fas/CD95 can be recruited and clustered. The co-clustering of Fas/CD95 and rafts facilitates DISC formation, bringing procaspase-8 molecules to be bunched together in a limited membrane region, and leading to their autoproteolytic activation by oligomerization. Lipid raft platforms serve as a specific region for the clustering of Fas/CD95 and DISC, as well as for the recruitment of additional downstream signaling molecules, thus forming the so-called cluster of apoptotic signaling molecule-enriched rafts, or CASMER. These raft/CASMER structures float in the membrane like icebergs, in which the larger portion lies inside the cell and communicates with other subcellular structures to facilitate apoptotic signal transmission. This allows an efficient spatiotemporal compartmentalization of apoptosis signaling machinery during the triggering of cell death. This concept of proapoptotic raft platforms as a basic chemical-biological structure in the regulation of cell death has wide-ranging implications in human biology and disease, as well as in cancer therapy. Here, we discuss how these raft-centered proapoptotic hubs operate as a major linchpin for apoptosis signaling and as a promising target in cancer therapy.
Proteolytic regulation of mitochondrial oxidative phosphorylation components in plants
Authors: Ghifari Abi S. , Murcha Monika W.
Published: May 2022

Mitochondrial function relies on the homeostasis and quality control of their proteome, including components of the oxidative phosphorylation (OXPHOS) pathway that generates energy in form of ATP. OXPHOS subunits are under constant exposure to reactive oxygen species due to their oxidation-reduction activities, which consequently make them prone to oxidative damage, misfolding, and aggregation. As a result, quality control mechanisms through turnover and degradation are required for maintaining mitochondrial activity. Degradation of OXPHOS subunits can be achieved through proteomic turnover or modular degradation. In this review, we present multiple protein degradation pathways in plant mitochondria. Specifically, we focus on the intricate turnover of OXPHOS subunits, prior to protein import via cytosolic proteasomal degradation and post import and assembly via intra-mitochondrial proteolysis involving multiple AAA+ proteases. Together, these proteolytic pathways maintain the activity and homeostasis of OXPHOS components.
Impact of the image alignment over frequency for the VLBI Global Observing System
Authors: Xu Ming H. , Savolainen Tuomas , Anderson James M. , Kareinen Niko , Zubko Nataliya , Lunz Susanne , Schuh Harald
Published: May 2022

Aims.The VLBI Global Observing System (VGOS), which is the next generation of geodetic very long baseline interferometry (VLBI), observes simultaneously in four frequency bands in the range 3.0-10.7 GHz (expected to be extended to 14 GHz). Because source structure changes with frequency, we aim to study the source position estimates from the observations of this new VLBI system.Methods.Based on an ideal point source model, simulations are run to determine the relation between the source positions as determined by VGOS observations and the locations of the radio emission in the four bands.

Results.We obtained the source positions as determined by VGOS observations as a function of the source positions in the four frequency bands for both group and phase delays. The results reveal that if the location of the radio emission in one band is offset with respect to that in the other bands, the VGOS position estimates can be shifted by a larger amount (up to more than three times that offset), possibly in the opposite direction.

Conclusions.The VGOS source positions will be highly variable with time and imprecise as to the locations of the radio emission in the four bands if the effects of source structure are not modeled. The image alignment over frequency is essential for modeling these effects, which is the only way to mitigate the impact of such frequency-dependent radio emission on the resulting VGOS source positions.
The Gaia EDR3 view of Johnson-Kron-Cousins standard stars: the curated Landolt and Stetson collections
Authors: Pancino E. , Marrese P. M. , Marinoni S. , Sanna N. , Turchi A. , Tsantaki M. , Rainer M. , Altavilla G. , Monelli M. , Monaco L.
Published: May 2022

Context. In the era of large surveys and space missions, it is necessary to rely on large samples of well-characterized stars for inter-calibrating and comparing measurements from different surveys and catalogues. Among the most employed photometric systems, the Johnson-Kron-Cousins has been used for decades and for a large amount of important datasets.

Aims. Our goal is to profit from the Gaia EDR3 data, Gaia official cross-match algorithm, and Gaia-derived literature catalogues, to provide a well-characterized and clean sample of secondary standards in the Johnson-Kron-Cousins system, as well as a set of transformations between the main photometric systems and the Johnson-Kron-Cousins one.

Methods. Using Gaia as a reference, as well as data from reddening maps, spectroscopic surveys, and variable stars monitoring surveys, we curated and characterized the widely used Landolt and Stetson collections of more than 200 000 secondary standards, employing classical as well as machine learning techniques. In particular, our atmospheric parameters agree significantly better with spectroscopic ones, compared to other machine learning catalogues. We also cross-matched the curated collections with the major photometric surveys to provide a comprehensive set of reliable measurements in the most widely adopted photometric systems.

Results. We provide a curated catalogue of secondary standards in the Johnson-Kron-Cousins system that are well-measured and as free as possible from variable and multiple sources. We characterize the collection in terms of astrophysical parameters, distance, reddening, and radial velocity. We provide a table with the magnitudes of the secondary standards in the most widely used photometric systems (ugriz, grizy, Gaia, HIPPARCOS, Tycho, 2MASS). We finally provide a set of 167 polynomial transformations, valid for dwarfs and giants, metal-poor and metal-rich stars, to transform UBVRI magnitudes in the above photometric systems and vice-versa.
Video synopsis algorithm based on two-stage target tubes grouping
Authors: Wang Yuting , Zhu Zhixiang , Wang Chenwu , Wang Pei
Published: May 2022

Video synopsis generates a concentrated video that can be browsed quickly. With the increase of condensation ratio, more pseudo collisions between target tubes will occur. To solve this problem, this paper proposed a video synopsis algorithm based on two-stage target tubes grouping. In the first stage, using the hypergraph to analyze the collision relationship between target tubes, and the target tubes are grouped according to the hyper-edges. In the second stage, a clustering algorithm based on equal distance nearest neighbor sampling is proposed to group the target tubes. Then, selecting target tubes according to the selection principle of quantity priority between groups and length priority within groups (QPB-LPG) . Finally, these target tubes are rearranged to generate concentrated videos with smaller pseudo collisions. The experimental results show that this algorithm can significantly reduce the pseudo collision between target tubes without reducing the frame condensation ratio and frame compact rate compared with existing video concentration algorithms, and the feasibility of the method is fully verified.
Design of a prefixspan algorithm based on prefix position form
Authors: Su Youcheng , He Xin , Wang Zilong , Wang Jianyu
Published: May 2022

PrefixSpan algorithm based on sequence pattern is an association algorithm without generating candidate sequences and only needs to scan the original sequence database twice in the whole operation process. Compared with other sequence algorithms, the PrefixSpan algorithm is more efficient and fast. In this paper, PrefixSpan Base on Prefix Position Form, PPFPrefixSpan is proposed by studying the characteristics of the PrefixSpan algorithm and optimizing it based on it. , which solves the problem that the PrefixSpan algorithm produces too many duplicate projection databases in the process of operation, and optimates the PrefixSpan algorithm in space/time.
Delta system transfer function model for IEMI time domain test
Authors: Ma Rupo , Wang Qun , Wang Zhenli , Pan Yanyan
Published: May 2022

Intentional electromagnetic interference (IEMI) is a serious threat to the stable operation of computer and other intelligent terminal equipment. For testing research on IEMI, it is very important to build a stable and reliable test system model for accurate analysis of test data. In the time-domain test of IEMI, the z-domain discrete system transfer function is usually used to describe the response characteristics of the test system. However, with the change of sampling frequency, the parameters of thez-domain model should change accordingly, which leads to inconvenience in modeling the test system. In this paper, aδ-domain transfer function model of the test system is constructed by the transformation fromz-domain. And theδ-domain model has better stability at high sampling rate and can be approximately equivalent to the system transfer function in the continuous-time domain.
Research on targeted service technology for early warning information of meteorological disaster based on NLP
Authors: Feng Yuxing , Tang Wei , Wang Muhua , Cao Zhiyu , Qiao Liang , Cui Lei
Published: May 2022

Affected by global climate change and the superposition of urban construction, the climate of city meteorological guarantee service puts forward new requirements and new challenges. As the first line of defense of meteorological disaster prevention and reduction, it is very important to realize the refinement targeted service of early warning information. There are some problems in the traditional early warning information service, such as the difficulty of accurate service of early warning information, the lack of precision, and the insufficient mining of early warning text information. This paper mainly analyzes the text description characteristics of early warning information of meteorological disaster, constructs the early warning information knowledge extraction process, constructs the early warning information labeling system, and realizes the early warning effective time extraction method based on conditional random field model, Early warning affected areas extraction method based on bidirectional long-term and short-term memory neural network and early warning cautions extraction method based on bootstrapping weak supervised learning method. Finally, taking the early warning information targeting service of meteorological information decision support system as an example, this paper tests the early warning information extraction methods, and preliminarily realizes the early warning precision targeting service in the decision support service of meteorological disaster prevention and reduction.
Fast all-focus image reconstruction method based on light field imaging
Authors: Wang Shuzhen , Zhao Haili , Jing Wenbo
Published: May 2022

To achieve high-quality imaging of all focal planes with large depth of field information, a fast all-focus image reconstruction technology based on light field imaging is proposed: combining light field imaging to collect field of view information, and using light field reconstruction to obtain a multi-focus image source set, using the improved NSML image fusion method performs image fusion to quickly obtain an all-focus image with a large depth of field. Experiments have proved that this method greatly reduces the time consumed in the image fusion process by simplifying the calculation process of NSML, and improves the efficiency of image fusion. This method not only achieves excellent fusion image quality, but also improves the real-time performance of the algorithm.
Design of short-circuit protection circuit for switching power supply
Authors: Wang Jian , Liu Xingzhi , Wu Youchao
Published: May 2022

Short-circuit protection circuit for switching power supply is designed. The circuit is for sampling and protection based on capacitance ripple characteristics. It has the advantages of rapid fault protection adjustable trigger time and recovery time. It shows that the circuit scheme has a good protective effect on the power converter in various load environments, and it has reached desired effect, according to the simulation results and the circuit application results.
Simulation on dynamic envelope gauge of NX70 flat car
Authors: Chen Chao , Han Yanhui , Han Mei
Published: May 2022

In railway transportation, the clearance provided between the vehicle and structure gauge is an important safe space. The general rules and methods for inspecting of rolling stock gauge are based on a static gauge in China. Dynamic envelope gauge calculation considers the rolling stock displacement much more than before. The paper combines dynamics simulation with the Standard for Metro Gauge to calculate the dynamic envelope gauge. The lateral static vibration offset caused by the error of manufacturing, installation and maintenance is calculated. The lateral dynamic vibration and the vertical dynamic vibration offset caused by the suspension and wheel/rail gap is obtained by dynamic simulation. According to the current structure gauge, the clearance between the dynamic envelope gauge and the structure gauge can be calculated and the safety of railways operation can be analyzed. As an example, NX70 dynamic simulation model is established. The clearance between the vehicle and structure gauge is enough to curve and straight line when the center height of gravity increased to 2400mm for NX70.
Research on stock index forecast based on the forgetting-genetic network model
Authors: Wei Bin , Zhang Mingshu , Liu Longfei
Published: May 2022

The stock market plays an important role in national economic development. Predicting its trend, to ensure market stability, efficiency, and safety, is one of the hottest topics of current research. Some algorithms have been proposed to use in this study, however, the drawback in forecasting accuracy and applicability of the model and other issues limit its application in practice. In this paper, we designed a forgotten-genetic network model to predict the stock index. Finally, a comparison between existing algorithms to verify the validity and applicability of the proposed method in this study.
Research on Chinese live broadcast marketing and sustainable consumption intention under the internet environment
Authors: Zhao Yihan , Lu Pingjun , Chen Wei
Published: May 2022

Compared with the traditional marketing model, the live broadcast marketing model increases the role of the anchor, making it a research hotspot. Based on different types of products and different anchor modes, the impact on consumers’ psychology and behavior is the focus of this paper. Through two standard experiments, spss22 0 statistical analysis found that: (1) for functional products, entertainment anchor mode significantly improves consumers’ emotional identity; at the same time, it significantly reduces consumers’ authority identity and knowledge identity; (2) for functional products, knowledge-based anchor mode significantly enhances consumers’ authority identity and knowledge identity, and significantly reduces consumers’ emotional identity; (3) In the functional product scenario, knowledge identity, authority identity and emotional identity all have a positive impact on consumers’ continuous purchase intention.
Accounting firms transformation and investor protection
Authors: Tan Wenhao , Sun Yun , Zhao Jianfeng , Sun Dian
Published: May 2022

The outburst of financial crisis gives a big hit to the global capital market, and makes the investors had a new cognition about the CPA (Certified Public Accountants). The capital market cannot develop healthily without the certified public accountants. The article aims to explain the legal responsibility of special general partnership, to expound the operation mechanism and responsibility formation mechanism of general partnership. It also aims to make a further analysis on problems of legal responsibility in special general partnership, in order to put forward how to define error or fraud, to set up the responsibility evaluation standard and restriction mechanism. The final purpose is to create a good guarantee system for the investors and promote the healthy development of capital market.
An optical access scheme with 1.25Gbit/s NRZ downstream signals over 6GHz subcarrier for next generation mobile systems application
Authors: Yang Qiming , Shao Yufeng , Wang Anrong , Wang Zhuang , Yang Jie , Yi Linfang , Yu Ni , Tian Qing , Liu Shuanfan , Zuo Renjie , Yuan Jie , Li Yanlin , Chen Peng , Li Chong
Published: May 2022

In order to solve the problem of network frequency resource congestion from the central office (CS) to the base station (BS) in sixth generation (6G) mobile communication systems, we design a passive optical network (PON) access scheme. 1.25Gbit/s non-return-to-zero (NRZ) downstream signals over 6GHz subcarrier are successfully transmitted in the 20km single-mode fiber (SMF) and allocated to 4 optical network units (ONUs). The radio frequency (RF) spectrums, optical spectrums, eye-diagrams and bit error rate (BER) before and after transmission of NRZ signals in the system were measured and analysed. The results show that, this scheme can provide high-speed, stable and secure data communication.
Research on trust issues in cloud computing
Authors: Lu Lilei , Li Zhaohui , Wu Shukun , Shang Yanhong
Published: May 2022

Although cloud computing has some eminent advantages such as low cost, resource elasticity, yet the highly dynamic, distributed and opaque nature of cloud services makes it a meaningful challenge to establish and manage trust between cloud service providers and consumers. Based on this background, this paper first describes the common concepts and classifications of trust issues and trust models, then generalize trust issues in cloud computing based on the research of existing work, next enumerates typical trust evaluation models from several different perspectives in cloud computing. Finally, conclusions including several potential trends are proposed for the future work.
Radar signals recognition based on attention and denoising residual network
Authors: Ding Jiajun , Yan Yunyang , Liu Yian
Published: May 2022

To solve the problem that complex radar emitter signals are difficult to identify under low signal-to-noise ratio, this paper proposes a novel radar signal recognition method based on an improved deep residual network. In this method, two IQ signals are used as the input of the method, which saves time for generating time-frequency images, and then the signal features are extracted through an improved deep residual network. A nonlinear transform layer is inserted into the network to automatically confirm the threshold value, and then the soft threshold method is used to denoise. The importance of features is weighted by attention unit, and then classified by softmax classifier. The experiments based on five kinds of radar signal datasets show higher accuracy at low signal-to-noise ratio compared with other methods. The experiments also verified its overall accuracy can still exceed 90% even at extremely low signal-to-noise ratio of -16dB.
Synthesis of silver coatings by brush plating with cyanide-free solution
Authors: Du Baoshuai , Zhang Zhongwen , Suo Shuai , Li Xinmei
Published: May 2022

Silver coating can be used to improve the surface properties of components made of copper in terms of corrosion resistance, wear resistance and electrical contact conductivity. A cyanide-free solution based on Na₂S₂O₃ is proposed for the brush plating of silver coating on copper substrate. XRD, SEM and microhardness tester were used to characterize the microstructure and properties of the coatings. It is found that this cyanide-free solution can deposit silver coating with high efficiency. Coatings consist of nano-sized grains which present as aggregated nodular morphology. The brush plated coatings show microhardness of 122.47 Hv, which is promising in the engineering application of electrical contact components.
Stress Analysis of Floating Photovoltaic Power Plants under Wind Conditions in 8x8 Arrangement
Authors: Yuan Bingqing , Bei Yaoping , Zhang Mingyu , Deng Xia
Published: May 2022

This paper adopts Sharepower solar floating photovoltaic power station unit. The structure is simulated and analyzed, the strength of a single solar structure support is analyzed, the photovoltaic array structure is analyzed, and the rectangular and square structures with different wind directions are analyzed.
Effect of annealing temperature on the photocatalytic performance of ZnO@MoS2 composite materials
Authors: Yang Weijia , Liu Lihua , Zhao Jingjing , Guan Zeyi , Lu Bingshang , Wang Fengming , He Xin , Fu Yuechun
Published: May 2022

In this work, we report the ZnO@MoS2 composite materials prepared by a hydrothermal method, and the effect of annealing temperature on the photocatalytic performance of ZnO@MoS2 composite materials. It is found that annealing temperature plays an important role in the formation of MoS2 surface morphology, resulting in the dense films and a reduction of nanostructure nummber and active sites by enhancing temperature. Furthermore, ZnO@MoS2 composite materials annealed at 50 oC possess a higher photocatalytic degradation efficiency of 62.88% on methylene blue solution compared with ZnO materials or other samples.
Methods and exploration for mechanical testing and microscopic testing of loess under freeze-thaw cycles
Authors: Liu Qingbo , Zhao Kai , Zhao Laishuan , Wang Linhao
Published: May 2022

The stability of loess subgrade is affected by many factors. Freeze-thaw cycles are a common factor that causes the strength of loess subgrades to be damaged. In order to study the influence of freezethaw cycles on the stability of loess subgrades, reveal the mechanism of freeze-thaw cycles on the strength of loess subgrades. It is necessary to sample the loess soil samples in this area, and perform compaction test, freeze-thaw cycle test, unconfined compression test and electron microscope scanning test on the soil sample to analyze the influence of freeze-thaw cycle on the strength and microstructure of loess soil. . In this way, the potential relationship between the microstructure and the strength of the soil can be obtained. The results found that the freeze-thaw cycle of loess led to a trend of first increase and then decrease in soil strength. The microstructure showed a trend of smaller soil particles and increased soil voids. The potential relationship between the microstructure and the strength of the soil was analyzed. It explains the conclusion that the strength of the soil first increases and then decreases.
Influence of preparation conditions on the physical structure and surface properties of enteromorpha clathrate bio-char
Authors: Liu Lu , Zheng Yali , Gong Peng , Shao Guangcai , Huang Xu
Published: May 2022

Bio-char with rich pore structure was obtained by pyrolysis of enteromorpha clathrate (EC) and subsequent activation process. The effect of pyrolysis methods, KOH concentrations used in activation and heating rate was studied. A new method that combined pyrolysis and activation into one step was proposed. The bio-char obtained via slow pyrolysis at 450°C and 700°C had a certain pore structure. The bio-char obtained via fast pyrolysis had almost no effective pore structure and a large amount of organic matters still exist in the bio-char, while it had the largest specific surface area after activation by KOH at 800°C. Therefore, bio-char that is a kind of by-product in the process of making bio-oil by fast pyrolysis of EC is worthy of further exploration. As the KOH concentration of the impregnated solution increased, the specific surface area first increased and then decreased. The bio-char obtained via impregnation and activation with 3 mol/L KOH had the highest specific surface area (1128.85 m2/g) and pore volume (0.789 cm3/g). If the processes of pyrolysis and activation were combined into one step via mixing KOH and EC, the structure of cell tissue in the EC was reserved. The sample that prepared by mixing 2 g dried EC with 0.1 g KOH powder has the highest specific surface area (724.66 m2/g) and better pore structure. The best heating rate was 5°C/min for impregnation method and 2°C/min for one step method.
Nonlinear error control of five-axis machining singular region
Authors: Chen Liangji , Liu Zhi , Li Zhiguang , Wei Zisen
Published: May 2022

Aiming at the singular problem of large nonlinear error caused by the extreme change of rotation in five axis NC machining of complex surface. An optimization algorithm of tool path in singular region is proposed. Taking a-c double turntable five axis linkage NC machine tool as an example, firstly, the mathematical models of tool local milling ability, machining bandwidth and tool axis inclination are established. Based on the two constraint models, the mechanism of singularity and the size of singular region are analyzed, and it is proposed to adjust the side angle with the tool contact as the rotation center to avoid the singular region. The modified tool axis vector that does not meet the accuracy is interpolated recursively according to the interpolation principle. This method solves the problem of large nonlinear error caused by the extreme rotation of the rotating axis in the singular region on the basis of meeting the requirement of no curvature interference. At the same time, the processing bandwidth before and after modification is guaranteed to remain unchanged. Simulation results show that the algorithm can effectively detect the singular region and improve the machining quality in the singular region.
Effect of surface insulation on thermal stress of concrete
Authors: Xin Jianda , Liu Yi , Wang Juan , Wang Zhenhong , Jiang Xiaoming , He Dingquan , Jiang Huaiyu , Hou Wenqian , Zhang Shixi
Published: May 2022

For concrete, the appearance of temperature load due to the hydration heat of cementitious materials is inevitable and important to the structural safety of dam. This paper investigates the effect of different surface insulation measures on the thermal stress of dam concrete by means of finite element simulation calculation. The calculation results show that surface insulation is important for lowering the surface thermal stress of concrete. When the equivalent surface coefficient of heat transfer was less than 3kJ/(m2·h·°C), the surface tensile stress can be decreased by 80%~90% for concrete undergoing diurnal temperature variation and cold wave.
Effect of ultrasonic wave on coating and corrosion of ZK60 magnesium alloy
Authors: Zhang Nana , Tong Zhibo , Li Hongyan , Liu Shichang , Li Qing , Xie Qiuyan , Ding Jianbo
Published: May 2022

In this paper, hydroxyapatite coating was successfully deposited on ZK60 magnesium alloy surface by ultrasound-assisted electrodeposition method, and the macroscopic structure, chemical composition and corrosion properties of ZK60 magnesium alloy sample and HA coating were analyzed. The results show that the quality of ZK60 magnesium alloy surface coating is improved by ultrasonic power, and the HA coating is uniform, smooth and compact. XRD and FTIR analysis show that the main composition of the coating obtained by ultrasonic assisted electrodeposition is hydroxyapatite. The results show that ultrasonic treatment is beneficial to the corrosion resistance of SBF solution.
Theory study of H2O adsorbed TiO2 (110) surface: structural and
electronic properties
Authors: Zhong Siying , Wu Shaoyi , Chen Xiaohong , Xu Kailai
Published: May 2022

There are three main crystal forms of TiO2 in nature: rutile, anatase and brookite. In this paper, the GGA-PBE method of density functional theory was used to study the H2O molecules adsorbed (110) surface of these three kinds of titanium dioxide. H2O molecules tend to polymerize into dimmers due to the increase of H-O bond length on the surface of rutile than anatase. The lowest adsorption energies of H2O molecules adsorbed on these three structures are −5.479, −0.085 and 4.278 eV, respectively. H2O molecule is most likely to be adsorbed on the (110) surface of anatase. As for H2O molecules adsorbed in the (110) surface of these structures, rutile exhibits the smallest changes of both host TiO2 and H2O molecules.
Dielectric Properties of Polypropylene by Deashing Method for DC Polymer Film Capacitors
Authors: Xing Zhaoliang , Zhang Chong , Dai Xiying , Li Fei , Xiao Yu , Li Jian
Published: May 2022

In this paper, a novel deashing method was proposed to prepare polypropylene (PP) materials with different ash contents (80 ~ 560 ppm). Effects of the ash on dielectric and energy storage characteristics of PP in polymer film capacitors were studied. The experimental results reveal that a low content of ash will help to improve the dielectric properties. Compared to the sample with 560 ppm of ash content, the PP film with 60 ppm ash possesses a lower DC conductivity (1.85×10-14S/m). After the purification, the decline of the ash content in PP prevents the local electric field distortion and enhances the breakdown strength, which is beneficial for the improvement of the discharge energy density. Meanwhile, the reduction in the number of carriers ionized by the ash weakens the transport behavior and reduces the conductivity. It is concluded that the PP with high purity shows a great potential in polymer film capacitors.
A profit maximization single item inventory problem considering deterioration during carrying for price dependent demand and preservation technology investment
Authors: Mahata Sourav , Debnath Bijoy Krishna
Published: May 2022

This paper addresses a single item two-level supply chain inventory model considering deterioration during carrying of deteriorating item from a supplier’s warehouse to a retailer’s warehouse as well as deterioration in the retailer’s warehouse. The model assumes preservation technology in the retailer’s warehouse to prevent the rate of deterioration. An upper limit for the preservation technology investment has been set as a constraint to the model. The model maximizes the retailer’s profit per unit time, simultaneously calculated optimal order quantity. A price dependent demand and storage-time dependent holding cost is considered to develop the model. Some theorems are proven to get optimal values of the total cost. A numerical problem is workout as per the developed algorithm and with the help of MATLAB software to study the applicability of our theoretical results.