bluuebunny/crossref_metadata_2025 huggingface dataset:
Sensorless Control of Switched Reluctance Motor Based on Matlab/Simulink Simulation
Authors: Gao Jinjian , Sun Baojiang , Huo Wenli
Published: February 2021

This article mainly introduces the acquisition of the position information of the switched reluctance motor through the inductance, which can make the switched reluctance motor(SRM) correct commutation. The main method is to apply high-frequency and low-duty pulse voltages to the two non-conducting phases of the switched reluctance motor when the motor is in low-speed operation, so that the non-conducting phase generates a response current through the rising slope of the response current The current change rate is obtained by the difference with the falling slope, and then the current change rate is converted into inductance through a formula, and whether the inductance reaches the inductance threshold is judged whether it reaches the commutation position, and the motor is subjected to timely and accurate commutation processing. This method is realized by matlab/simulink simulation, and combined with the high-speed inductance method obtained by the flux ratio current, to realize the position sensorless technology combined with the inductance method in the full speed cycle, and the simulation verifies that the low-speed and high-speed algorithms can be smooth Switch, and can realize its commutation control function, and It provides simulation support for applications such as lawn mower.
Dynamic Aircraft Conflict Alert Based on the Markov Decision Process and Simulation of Actual Flight Data
Authors: Li Jie , Song Ruiliang , Zhang Haipeng
Published: February 2021

As air traffic flow continues growing, the risk of collision between aircraft is also increasing as well. In order to ensure efficiency of airspace would not reduce due to the increase of the conflict, and thus the accuracy of alerts also has higher requirements. Traditional conflict alerts based on the static threshold method will have a great flight separation redundancy, resulting in reduced operating efficiency of airspace. So it’s necessary to study the dynamic threshold alerts approach based on actual flight scenes, which can dynamically adjust the threshold and improve operational efficiency. First in this article, Markov decision processes were introduced. And then proposed a dynamic threshold alert method based on the Markov decision process. Finally, the analysis of alert results were performed through simulation of actual flight data. The results show that this method can reduce the false alert rate and improve the performance of the alert system under the premise of ensuring flight safety.
Data-driven Modeling of the Methane Adsorption Isotherm on Coal Using Supervised Learning Methods: A Comparative Study
Authors: Feng Qihong , Wang Jiaming , Zhang Jiyuan , Zhang Xianmin
Published: February 2021

Methane adsorption isotherm on coals is key to the development of coalbed methane (CBM). Laboratory measurement of adsorption isotherm is time-consuming. This paper presents a comparative study on the accuracy and robustness of seven supervised learning (SL) methods in estimating the methane adsorption isotherm based on coal properties. The SL methods used include the Gaussian process regression (GPR), kernel ridge regression (KRR), classifier and regression tree (CART) and four ensemble decision tree methods (random forests (RF), Adaboost, gradient boosting decision tree (GBDT) and extreme boosting (XGBoost)). The results show that all these SL methods are capable of correlating methane adsorption amounts with the feature variables with reasonable accuracies in the training stage. However, the KRR, GBDT and XGBoost are demonstrated to outperform other SL techniques in terms of the robustness and generalization capability, which therefore are recommended for fast estimation of the methane adsorption isotherms on coals.
Dynamic Path Planning of Underwater Vehicle Based on Pulse Lidar Profiler
Authors: Chen Xinghong , Tao Li
Published: February 2021

In the underwater environment, the speed of light is much faster than that of sonar, so it can be used to sample and detect more intensively in space and high frequency in time. A better strategy is to integrate sonar and lidar into an integrated device. In military affairs, lidar sonar system is used for identification of underwater artificial works and fixed-point blasting. In the civil field, aquaculture, scientific research and sampling, and underwater infrastructure exploration are the main areas. This paper analyzes the application of pulse lidar profiler system integrated with multiple detection methods in the dynamic path planning of underwater vehicle. Three colors of “red, orange, red sauce” were used as the warm color light source group, and three colors of “blue, green, purple” were used as the cold color light source group. Through matrix operation, underwater objects with almost all colors can be quickly reached and superimposed. The speed of sound wave is slow, but the bypass performance is very good, which fully supplements the blind area of light source.
An Improved K Nearest Neighbor Classifier for High-Dimensional and Mixture Data
Authors: Tuerhong Gulanbaier , Wushouer Mairidan , Zhang DongMei
Published: February 2021

Conventional K nearest neighbor classifier is challenged by data with high-dimensional and mixture of continuous and categorical variable characteristics. To address this issue, we propose an improved K nearest neighbor classifier by using principal component mixed also called PCAmix. First, we employed the PCAmix to preprocess high-dimensional and mixture data. Then, the KNN classifier is used to classify objects characterized by high-dimensional mixture of continuous and categorical variables. We have evaluated our method using five mixture datasets that are available from the UCI machine learning repository and compared our results with the base line approaches. The experimental results showed that the proposed method had better classification performance for high-dimensional mixture data.
Data Analytics for the 3-extra Diagnosability of Bubble-sort Star Graphs
Authors: Zhao Jutao , Wang Shiying
Published: February 2021

The underlying topology of a large processor system is usually represented by a graph. The g -extra diagnosability of graph G requires that each fault-free component has at least (g + 1) fault-free vertices. It is difficult to prove this problem. The n -dimensional bubble-sort star graph BS has many excellent properties. We show that the 3 -extra diagnosability of BSn
is 8n − 20 under PMC and MM model for n ≥ 5 and n ≥12, respectively.
An Automatic Method of Sequential Image Processing
Authors: Kong Liangliang , Chen Lin , Wang Man
Published: February 2021

As the visual storage of objective things, images are usually used everywhere in the field of electronic information. Images of objects are collected or drawn to make electronic image files, which are stored into image files, and may be classified into different folders. Image users, such as accounting, HR and so on, often need to reprocess the images and save them into a word file when they use the images. Such manual processing of images is time costing and labor costing. In this paper, a method of automatically inserting and processing images is proposed and implemented. In the method, the sequence of inserting files is recorded in an excel file. Only the name of image file and the excel file need to be maintained. It is convenient to use the method to process images, and the method can be implemented automatically. So it is an effective way to help staffs to edit and insert images.
Screening of Candidate Key Genes Associated with Congenital Heart Disease Using Bioinformatics Data Analysis
Authors: Zhang Jingshu , An Xuyao , Sun Xiaohan , Yu Kun , Gong Tianxing
Published: February 2021

Congenital heart disease (CHD) is one of the most dangerous diseases seen in daily life. Aim of this study is to find the deep causes of congenital heart disease. The GSE35776 chip data was extracted from the Gene Expression Synthesis Database (GEO). Analyzing above data was using the R language. The enrichment pathways of differentially expressed genes were processed using the Kyoto Encyclopedia of Genes and Genomics (KEGG) and gene ontology (GO) database. Then this study uses Cytoscape and GCBI to structure protein-protein interaction (PPI) networks, gene regulation networks. 257 differentially expressed genes (DEGs) were found out, mainly focusing on cell cycle, oocyte meiosis, p53 signaling pathway and progesterone mediated oocyte maturation. By constructing gene regulation network, 12 hub genes were screened, including NUF2, BUB1, CENPI, CCNB2, SGO1, SMC4, NCAPD2, TUBB and NCAPH. We hypothesized that these 12 genes may be key factors in CHD.
Analysis and Research Based on Method of Questionnaire Survey and the Algorithm of Big Data Analysis
Authors: Xiao Fuliu , Song Bei , Liu Kun , Qu Chiwen
Published: February 2021

During the COVID-19 epidemic, the whole country suspended classes in schools without stopping studying. Under this circumstance, online teaching experienced a breakthrough development. This paper uses the method of questionnaire survey and the algorithm of big data analysis, and this paper explores the general situation of online teaching in local colleges and universities in southwest Guangxi which face challenges in online learning due to the relative shortage of educational resources and remote geographical location. This paper analyzes the supporting conditions, problems and shortcomings of online teaching in local colleges and universities in southwest Guangxi. Suggestions are also proposed on four aspects to improve online teaching and learning experiences, which are establishing the basis of online teaching conditions, strengthening the basic rules of online classroom management, improving teachers and students’ adaptation to online environment, and guiding students to improve independent learning ability.
Word Frequency Data Analysis in Virtual Reality Technology Industrialization
Authors: Liu Jinyu , Yang Teng
Published: February 2021

Virtual reality technology is increasingly in demand for economic, social and management applications, with Moore’s Law gradually failing, it’s difficult to balance the relationship between realistic needs and advanced technology by relying solely on technological progress, and even falling into the “IT black hole”, hindering the industrialisation of virtual reality technology. This paper uses word frequency analysis to extract the four most frequently occurring keywords from current policies, literature and other secondary sources, and abstracts them into four social support concepts: conceptual awareness, education, regulation and finance, to explore the inner connection between virtual reality technology and social support systems through comparison, and to realise the socialisation of virtual reality from the perspective of virtual reality. By comparing and exploring the intrinsic links between virtual reality technology and social support systems, the socialisation of virtual reality technology is realised from the perspective of virtual reality, thus realising the socialisation of technology.
Simplification Algorithm and Analysis of Random Sequence Test Packets based on Filtering Ability
Authors: Wang Zekun , Zhang Fuxi
Published: February 2021

A method was presented for simplifying the random sequences by means of introducing the concept of “the ability of filtering”. On the basis of explication of the relationship between each test and In-depth analysis of the role and contribution of individual tests to the overall test, the algorithm and implementation plan of simplified test package were proposed. Three procedures for filtering descending permutation tables for simplifying links and the algorithm for simulation results were discussed.
A Fuzzy Clustering Based Anomaly Node Detection Method for Publish/Subscribe Distributed Systems
Authors: Wang Defeng , Shen Zhuowei , Wu Wenjun
Published: February 2021

Timely and accurate understanding of the node running status can effectively control the propagation of faults in publish/subscribe distributed systems, which is of great significance to ensure the reliable operation of applications. A method of anomaly node detection based on fuzzy k-means clustering algorithm is proposed. Compared with the traditional K-means algorithm, this algorithm introduces fuzzy membership matrix to realize fuzzy clustering, and uses the idea of local reachability density to improve the selection method of cluster centers. Experimental results show that this method can effectively detect anomaly node in publish / subscribe distributed systems with higher accuracy, recall and F-measure than traditional K-means algorithm. The precision of publish anomaly detection and network anomaly detection is improved by 10.53% and 38.6% respectively.
Ship Target Image Segmentation Algorithm Based on Fuzzy Level Set
Authors: Zhang Yu , Li Yuntao , Guo Yonghui , Zhou Zheshuai
Published: February 2021

The effective recognition of ship target is very important for the protection of ocean rights, and the image segmentation is the precondition of the ship target recognition. To solve the two problems existing in the traditional level set graph, namely the increase of image segmentation and the increase of computation, the Fuzzy C-Means (FCM) and level set are introduced. A new algorithm for image segmentation based on fuzzy level set is proposed in this paper. The algorithm can use spatial fuzzy clustering to realize the parameter estimation and evolutionary adjustment. The algorithm is applied to optical remote sensing ship target image segmentation in complex sea environment, and the effectiveness of the proposed algorithm is verified by experiment results.
The Research of Quantitative Evaluation Algorithm of Process Auto Alarm Analysis Based on Chem-HRA
Authors: Jiang Xue , Dang Wenyi
Published: February 2021

For the process alarm management of chemical process safety analysis, its reliability mainly depends on the design of the safety limit and the optimization of the technical process, but there are few studies on the overall reliability level of process alarm based on the alarm disposal rate under the influence of human factor reliability. By focusing on independent layer analysis technique in the alarm and response, we combined the human reliability analysis (HRA) technology and Bayes theory, to form Human Reliability Analysis in chemical process safety(Chem-HRA), an optimized quantitative evaluation algorithm for chemical alarm failure frequency. The algorithm was applied to a risk event on tank farm’s cut over, ensuring the reliability and accuracy of petrochemical process analysis and disposal of the process alarm.
Application of Text Dimensionality Reduction Method in Information Filtering on Railway Transit Cloud Platform
Authors: Qiu Ye , Li Gang , An Junfeng
Published: February 2021

This paper focuses on the useful information data extraction of urban rail transportation’s urban rail cloud platform. Through the correlation and redundancy between feature items in the text vector space of a large amount of information data, a method of clustering text vector space dimensionality reduction is proposed and applied to the information data extraction of urban rail cloud platform. The vector aggregation theory and feature selection are applied to reduce the dimensionality of the feature space, so that the reduced dimensional feature items are more representative of the category. Through test experiments, it is proved that this text dimensionality reduction method algorithm is applied to the information data filtering of urban rail cloud platform, which effectively reduces the dimensionality of vector space and improves the accuracy and speed of text classification in urban rail cloud platform information data.
The Simulation Study of Multi-User Spread-Spectrum Wireless Communication System
Authors: Zhang Ling
Published: February 2021

Spread-spectrum technology is a promising and effective is an effective technique using for multiple accessing, combating multi-user interference and rejecting unwanted radio jamming. In this paper, we explore the effect of Direct Sequence spread-spectrum (DSSS) which base on π/4-DPSK modulation and demodulation technique, we provide a multi-user spread-spectrum wireless communication system and the system performance was studied from simulation and comparison. Four users information are transmitting over Rayleigh fading channel to model the 5G communication environments. The performances of the system are expressed through comparisons of the bit-error rate (BER) and signal to noise ratio (SNR) for both original signals at transmitter and recovered signals at receiver. From the contrast results, the anti-multi-user interference ability of the system is provided.
High Frequency Edge Information-based Sampling Algorithm for Multi-scale Block Compressive Sensing
Authors: Zhao Faqiang , Song Zejun , Li Jiayi , Zhu Binbin
Published: February 2021

The same sampling rate is applied to all subblocks of the same layer, which results in the deviation of the information contained in the sampling observation in the multi-scale block compressive sensing algorithm from the real information of the original image, thus affecting the accuracy of image reconstruction. For this reason, the multi-scale block compressive sensing adaptive sampling method (HEM) using HF edge information is proposed. In this method, the edge information is extracted by using the high frequency coefficients of wavelet transform, and then the edge information of the subblock of wavelet decomposition graph is calculated, and then converted into the adaptive sampling rate of each subblock. The influence of different decomposition layers and block sizes on HEM method is discussed through testing in 6 standard images. The experimental results show that the proposed algorithm can improve the PSNR of the reconstructed image at the same sampling rate on standard test images and cable trench inspection images. Among them, Stanwick image(S=0.1 and S=0.2), Russland image(S=0.3) and Stomach CT image(S=0.4) are partial exceptions.
Research on the Influence of Information Technology on Industrial Competitiveness
Authors: Wang Dong
Published: February 2021

Information technology, also known as information and communication technology, is mainly used to manage and process information. Information technology not only improves the operation and management efficiency of enterprises, but also gives birth to a new business model of the industry. Also, it has a profound impact on the competitiveness of national and regional industries. By analyzing the influence of information technology on four determinants and two external forces of Porter’s diamond model, this paper reveals the influence of information technology on industrial competitiveness.
The Prediction of New Medical Resources in China during COVID-19 Epidemic Period Based on Artificial Neural Network Model Optimized by Genetic Algorithm
Authors: Sun Fumin , Su Jie , Hu Yong , Zhou Ling
Published: February 2021

In this paper, a neural network model is constructed to predict the number of new infections, and on the basis of this model, the demand for medical resources of new infections is further predicted. Firstly, the traditional Back Propagation neural network is optimized by genetic algorithm, which solves the problem that Back Propagation neural network is easy to fall into the local optimal solution in the prediction. Taking the number of severe patients, the number of cured patients, the number of deaths, and the number of suspected patients on the first day of the new crown period as the input variables, and the number of newly diagnosed patients on the second day as the output variable, a new Back Propagation neural network is constructed Novel coronavirus pneumonia model is constructed. Secondly, according to the official documents on the new crown pneumonia research and the guide for the use of medical resources, the linear function of the infection proportion and the normal distribution function of each symptom duration are constructed. Finally, combined with the above two contents, a complete process is designed to achieve the medical treatment for the newly infected patients. Prediction of the demand for medical resources.
A Smoothness Regularized Low-Rank Completion Method for Power Grid Middle Platform Data
Authors: Wang Jijun , Xu Mingsheng , Zhou Situ
Published: February 2021

Currently, the construction of power middle platform plays a vitally important role in the evolution of the smart grid. However, due to sensor failures or network delays, the sampled power middle platform data is often inevitably missing. To address this challenge, in this paper, we propose a smoothness regularized low-rank completion method for power middle platform missing data. Technically, the acquired middle platform data are formed to a time-series data matrix. Then, the low-rank matrix recovery model is applied to complete the missing data. Since the middle platform data is time-continuous, we adopt a total variation term to use this piece-wise smoothness. Finally, the proposed model is efficiently solved by the distributed alternating direction method of multipliers. Experimental evaluations on a real middle platform dataset validate the performance of the proposed method.
A Typical Failure Mode and Effects Analysis for EMA Used for UAV and Guided Missile
Authors: Wu Jiufeng , Yang Tao , Cao Xinlei
Published: February 2021

Scout and strike UAV (Unmanned Aerial Vehicle) is one of the important products of latest UAV technology, which is becoming prevalent in modern war. The scout and strike UAV can complete scout tasks efficiently and hit the target with the guided missile accurately. And also the military use of scout and strike UAV brings low casualty. It attracts more and more attention. EMA is the actuator of the UAV and the guided missile. It controls the control surface, rotation of which determines the flight attitude, exerting heavy influence on the flight safety. Failure mode and effects analysis is an important tool for EMA (Electronic Mechanical Actuator) design, for the simple reason that it helps to assess EMA reliability, maintainability and safety. In this paper, a typical failure mode and effects analysis is conducted with EMA as the research object. EMA system definition and FMEA (Failure Mode and Effects Analysis) basic principle are presented. And then the detailed analysis is given based on some certain rules and the FMEA table illustrates the analysis. To summarize, the failure mode and effects analysis offers reference for EMA design. With it, the weak part in the design can be found and some potential risks can be eliminated in early stages of EMA design.
Research and Implementation of a Humanoid Robot Control Method Based on Action Mapping
Authors: Li Xuezhen , Zhang Yuanwen , Yang Rui , Zhang Jiayun
Published: February 2021

In order to reduce programming difficulty and let humanoid robot act more humanlike, we designed a robotics control method for humanoid robots. Firstly, based on human body movements collected by Kinect camera, we calculated 3D data of joint point with pinhole model, and established space model of robot and skeleton model of human. Then, we transformed 3D coordinates of human joints into joint values by space vector method, mapping to the joints of the robot and guides the robot to move. Finally, with semi-autonomous control experiment, it shows that humanoid robot action mapping strategy is feasible and effective. Compared with the existing similar research, this paper implements the action guidance control of humanoid robot, enhances the intelligent degree of robot and expands the application scene and scope of humanoid robot. Depending on the human-like appearance, humanoid robot with action mapping could provide a much more intelligent interaction method.
The Role of Colour Perception in Visual Sustainability: a Survey of Senate Building Facades in Selected Universities in Southwest, Nigeria
Authors: Oludare Obaleye J. , Adeboye Albert. B. , Ezema Isidore. C.
Published: February 2021

Colour perception is essential in the appreciation of the physical world. The inclusion of colour in the consideration of sustainable development of buildings is an important environmental and social factor which calls for distinguishing different colours for diverse building typology. This paper was aimed at identifying public colour preference for senate building facade in selected universities in southwest Nigeria, with a view to establish distinct colour scheme for office buildings. A survey research design was adopted with the stratified random sampling technique used in selecting respondents. Primary data were obtained through the administration of questionnaire to 577 users from ten selected universities. Photographs of 10 selected university senate building façade were attached to the questionnaire to serve as bases for assessing the buildings. Data was analysed using frequencies, percentages and mean ranking. The study revealed that façade colour is an important architectural element for visual sustainability and lighter shades of different colours were observed to be most preferred by the respondents in the study area. The study recommended the need for equipping the design professionals on the fundamentals of colour choices as an architectural design element for building façade attractiveness.
Determination of cross-sectional void fraction in a two-phase water flow through a PVC pipe
Authors: Ajesi O.H. , Latif M.B. , Gbenu S.T. , Onumejor C. A. , Fasasi M. K. , Akinpelu A. , Arijaje T. E. , Oyeyemi K. D.
Published: February 2021

Gamma ray transmission method for void faction measurement studies is in rare use in Nigeria, especially in industries and research. The study used this method to determine the cross-sectional void fraction of two-phase water flow through a Polyvinyl chloride (PVC) pipechannel. The gamma-ray counts transmitted through the water pipe were recorded and used to calculate the void fraction using a semi-empirical approach. Void ratio values varying from 0.171 – 0.036 were obtained for water flow rates ranging between 0.5gal/min - 4.0gal/min at estimated constant air flow rate. Conclusively, the experimental results compared well with Chisholm theoretical model predictions of void ratio applicable to horizontal flow. The use of two or more theoretical model predictions is recommended for further comparative study with experimental process. Also, more use of gamma ray transmission method should be encouraged.
Simulation and Techno-economic Analysis of a CO2 Capture Scheme for Combustion Processes
Authors: Babatunde Damilola E. , Anozie Ambrose N. , Omoleye James A.
Published: February 2021

Literature search has revealed that most post-combustion CO2 capture processes available to power plants are hinged on sorption technologies (chemical absorption and desorption) which are cost and energy-intensive. The colossal cost of solvents used for the absorption of CO2, the high energy requirements for the absorption & solvent recovery processes, plant design & control related complications, and environmental concerns about the solvents are some of the challenges associated with this option of post-combustion CO2 capture approach which is widely being adopted to mitigate CO2 emissions from power plants. In this study, the capture of CO2 from flue gas by exploring the concept of change of state of matter, which is essentially a physical approach to CO2capture, is presented as an alternative to the typical methods in the industry.
The Vector dynamics of Ikogosi Wind Speed/direction relative to Climate Change
Authors: Abodunrin T.J. , Emetere M.E.
Published: February 2021

This study appraises anticipated vicissitudes to surface wind characteristics from 1980-2018 in Ikogosi South-Western Nigeria. Changes in wind speeds at regional and global levels are signals of global warming. A concern about climate change has been a major driving force for the speedy expansion experienced in wind energy projects. Yearly investigation of wind speed disguises seasonal variation in predictive planning. At times, these changes fluctuate across seasons in some zones. The Inter-governmental Panel on Climate Change (IPCC) gave a proponent for long-term changes in the large-scale atmospheric circulation. In effect, observed changes such as poleward shifts and reinforcement of westerly winds will likely be promoted. Projected changes to annual wind speed display altitudinal variability compared to seasonal and annual mean wind speed. An evaluation of wind changes at specific locations is therefore necessary for site-specific application. This paper presents experience at Ikogosi warm spring site with varying return periods, analysedfor identificationof the behaviour of its wind using several statisticsprobability distribution. Average wind speed of 2.2 m/s in Ikogosi certainly portends a future for hydro-electricity alternative in Nigeria.
Reliability Assessment of an Off-Grid Hybrid Micro-Grid Power System (HMPS) for a Remote Community in Nigeria
Authors: Amuta E.O. , Wara S.T. , Agbetuyi A.F. , Adoghe U.A. , Olajube A.
Published: February 2021

Power System reliability assessment is one of the most crucial mensurations to evaluate power provider services and continuous availability. Hybrid Renewable Energy Systems (HRES) are an effective means to provide off-grid electrification to the rural areas that predominantly do not have access to electricity. This paper presents the reliability performance of a typical remote Obayantor community hybrid micro-grid in Edo state, Southern Nigeria. The hybrid energy system provides power for 90 households via a combination of 300W Solar Photovoltaic (PV) Modules, 1200Ah back-up battery system, and a 65kW diesel generator. The PV modules generate power throughout the day; the back-up provides energy source in the night while the diesel generator is sparingly used only in the event of faults, maintenance, or repairs. The reliability indices calculated were Mean Time to Repair (MTTR), Mean Time Between Failure (MTBF), and Availability using the outage data obtained from the microgrid between 2015 and 2019. The results recorded showed that the micro - grid was always available due to low downtime and low frequency of outages over the five years studied. Except in 2018, when the result recorded had the highest rate of power of interruption, which gave rise to the smallest value of availability and MTBF obtained in the same year. 2015 and 2019 had the highest availability value of 99.8%, and this value showed a similar trend to MTBF with the highest value in 2015 and the minimum value in 2018.
Density Functional Theory Approach to the Study of the Structural Stability of Nitrides of Iron and Nickel
Authors: Atsue T. , Oyewande O. E. , Ogunniranye I. B. , Aizebeokhai A. P.
Published: February 2021

Nitrides of transition metals such as iron and nickel are known to possess excellent properties relevant for technological applications. Among these, FeNhas been synthesized in zinc blende face centered cubic (F4

3

¯

M) crystal structure while NiN has not been synthesized yet. Literature search revealed that hexagonal close packed and primitive tetragonal structures of these compounds have not been investigated to ascertain their preference.Therefore, the structural stability of Zinc blende face centered cubic, hexagonal closed packed and primitive tetragonal crystal structures of the compounds were investigated in this study. Generalized gradient approximation of Perdew-Burke-Ernzerhof revised for solids (GGA-PBEsol) as implemented in Quantum espresso package was used based on density functional theory for the computation. The results revealed that FeN and NiNcompounds prefer Zinc blende face centered cubic crystal structure as their equilibrium lattice parameters occurred at the least equilibrium minimum energies in this structure. The lattice parameters of FeN and NiN compounds in thezinc blende FCC crystal structure were computed to be 4.232 Å and 4.324 Å respectively in agreement with experiment and previous computations. The preference of zinc blende FCC crystal structure by these compounds imply they may possess highly directional covalent bonds that prefer a tetrahedral arrangement of atoms, thus forming good binary semiconductor compounds. Therefore, these compounds have high possibility of been synthesized in zinc blende FCC crystal structure.
Rare earth elements in Uranium ore for nuclear forensic application
Authors: John S.O.O. , Usman I.T. , Akpa T.C. , Ibrahim U.
Published: February 2021

The contents of the Lanthanides, which are Rare Earth Elements (REE), that show consistent patterns under changing geochemical conditions in uranium ore have been studied. The objective is to determine the nuclear forensic parameters inherent to the various uranium ore samples collected from parts of northern Nigeria using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) analytical technique for the purpose of baseline data generation and nuclear forensic application. The REE fingerprint obtained in this study suggests that the uranium is of uraninite/pitchblende granitic (vein-type) origin. The REE concentrations varied from 0.011 ± 0.000 ppm to 2.337 ± 0.082 ppm for Riruwai, 0.001 ± 0.000 ppm to 0.035 ± 0.002 ppm for Mika-I, 0.002 ± 0.000 ppm to 0.357 ± 0.007 ppm for Mika-II and 0.001 ± 0.001 ppm to 0.159 ± 0.005 ppm for Michika. A positive correlation between the REEs showed symmetrical chemical properties as well as their overall presence in the samples. The normalised REE/Cl-Chondrites pattern show Light Rare Earth Elements(LREE) enrichment, Heavy Rare Earth Elements (HREE) fractionation with a negative Europium (Eu) anomaly. The ΣLREE/ΣHREE ratio presented varied values for the samples while a negative value of 143Nd/144Nd ratio (0.512638) in the Chondritic Uniform Reservoir (CHUR) ε
Nd(-0.64285) suggested LREE uniformity and radiogenic origin.
Soil salinity and its implications on sustainable agriculture in Southern and Northcentral States of Nigeria
Authors: Kayode O. T. , Aizebeokhai A. P. , Odukoya A. M.
Published: February 2021

Soil salinity impedes agricultural production, threatens global food security and agricultural profits. Soil salinity is a global issue and the accurate assessment of salt affected areas can assist in combating global climate change, effectively manage and utilize limited land and water resources. Landsat series of the multispectral remote sensing provides the potential for frequent surveys for soil salinization at various scales and resolutions. For this research, twenty tiles of Landsat 8 imagery between 2018 and 2019 were used to generate the soil salinity index map for the study area. The result revealed the salinity index status for all the areas investigated. Reclamation of salt affected land and management practices to curb soil salinity is highly recommended.
Large-scale Agricultural Investments and Female Employment in Nigerian Communities
Authors: Edafe O. O. , Osabuohien E. , Osabohien R.
Published: February 2021

This study examines how large-scale agricultural investments (LSAIs) affect employment outcomes of female households in Nigeria. It focuses on wage income and labour allocations to agricultural activities for households in communities with LSAIs compared with households in communities without LSAIs. It engages Wave 4 (2018/2019) of the Living Standards Measurement Study-Integrated Surveys on Agriculture (LSMS-ISA) dataset using the Propensity Score Matching (PSM) technique. The results show a positive relationship with the household income living in communities with LSAIs, but a negative relationship with the labour allocation to agricultural activities. Furthermore, the findings indicate that households in communities with LSAIs received higher wages and spend fewer hours in agricultural activities. Also, though female-head households spend more hours on agricultural activities than male-headed households, they earn less. Therefore, the study submits with some recommendations on reducing the possible adverse effects of LSAIs and optimising its positive impact, especially for females in rural communities where most of such investments occur.
A conceptual framework for evaluating public housing for resilience to rapid population growth
Authors: Equere Enobong B. , Ibem Eziyi O. , Alagbe Oluwole A.
Published: February 2021

The concept of resilience is increasingly being used in discourses on cities. However, there is paucity of` studies on the evaluation of public housing for resilience to urban population growth, especially in a developing country like Nigeria. This paper explored the concept of resilience on housing, and proposed a conceptual framework for the evaluation of public housing towards achieving resilience to the impacts of rapid population growth in cities. The methodology adopted includemapping the multidisciplinary data sources; reviewing the literature and categorizing the selected data; identifying and naming the concepts; deconstructing and categorizing the concepts and systematicintegration of the concepts to form the framework. The basic concepts identified in the literature for studying housing for city resilience in the face of rapid population growth were the vulnerability, adaptability and systems thinking theories. Based on these construct of theories, the study developed the conceptual framework around four key components. These components were (i) the impacts of rapid population growth on the social, economic and environmental fabrics of the city, (ii) the strategies or interventions that the actors can adoptthrough design and development characteristics, and building adaptive capacities towards the impacts, (iii)the effect of this strategies and interventions on the design and development of public housing and (iv) the systemic approach towards optimising the capacity of public housing schemes to absorb the adverse impacts of rapid population growth. This study contends that theoretical approach is important in understanding the development of housing that would promote city resilience in the face of growing negative impacts of rapid urbanisation in developing countries. It suggests the adoption of the proposed conceptual framework as guidelines to architects and other housing development professionals, as an evaluation parameter for resilience research and solving housing delivery problems in cities of developing countries.
Effects of annealing temperature on microstructural, magnetic properties, and specific absorption rate of Zn-Ni ferrite nanoparticles
Authors: Suharyadi Edi , Pratiwi Sri Handika , Indrayana I Putu Tedy , Kato Takeshi , Iwata Satoshi , Ohto Keisuke
Published: February 2021

Zn-Ni ferrite nanoparticles were successfully synthesized by coprecipitation method. The samples were annealed at various temperatures, i.e., 200 °C, 400 °C, 600 °C, 800 °C, and 1000 °C. The nanoparticles have the mixed spinel phase structure as confirmed by the X-ray diffraction patterns. The crystallite size was 15.1 nm and increased to 25.1 nm after annealing at 1000 °C. Transmission electron microscope images showed that the annealed sample exhibited better dispersion and grain boundaries compared to the as-prepared sample. Fourier transform infra-red spectra showed the existence of vibrations at 378 cm−1 and 555 cm−1, confirming bonding for mixed spinel ferrites. The hysteresis measurement by using vibrating sample magnetometer confirmed that the sample possessed soft magnetic properties with a coercivity of 45 Oe and increased after annealing. The saturation magnetization of the as-prepared sample was 11 emu g−1, and increased to 58 emu g−1 after annealing at a temperature of 800 and 1000 °C. The specific absorption rate (SAR) with an alternating current magnetic field (50 Hz and 100 Oe) of Zn-Ni ferrite before and after annealing (at 800 °C) was 63.7 and 92.4 mW g−1, respectively. The results showed that annealing temperature has a significant role in determining the microstructural, the magnetic properties and the SAR of the nanoparticles.
Quantum information processing with bosonic qubits in circuit QED
Authors: Joshi Atharv , Noh Kyungjoo , Gao Yvonne Y
Published: February 2021

The unique features of quantum theory offer a powerful new paradigm for information processing. Translating these mathematical abstractions into useful algorithms and applications requires quantum systems with significant complexity and sufficiently low error rates. Such quantum systems must be made from robust hardware that can coherently store, process, and extract the encoded information, as well as possess effective quantum error correction (QEC) protocols to detect and correct errors. Circuit quantum electrodynamics (cQED) provides a promising hardware platform for implementing robust quantum devices. In particular, bosonic encodings in cQED that use multi-photon states of superconducting cavities to encode information have shown success in realizing hardware-efficient QEC. Here, we review recent developments in the theory and implementation of QEC with bosonic codes and report the progress made toward realizing fault-tolerant quantum information processing with cQED devices.
Quantitative structure of stable sets in arbitrary finite groups
Authors: Conant Gabriel
Published: February 2021

We show that a

k
k

-stable set in a finite group can be approximated, up to given error

ϵ
>
0

\epsilon >0

, by left cosets of a subgroup of index

ϵ

-

O
k

(
1
)

\epsilon ^{\text {-} O_k(1)}

. This improves the bound in a similar result of Terry and Wolf on stable arithmetic regularity in finite abelian groups, and leads to a quantitative account of work of the author, Pillay, and Terry on stable sets in arbitrary finite groups. We also prove an analogous result for finite stable sets of small tripling in arbitrary groups, which provides a quantitative version of recent work by Martin-Pizarro, Palacín, and Wolf. Our proofs use results on VC-dimension, and a finitization of model-theoretic techniques from stable group theory.
Adams’ inequality with logarithmic weights in ℝ⁴
Authors: Zhu Maochun , Wang Lianfang
Published: February 2021

Trudinger-Moser inequality with logarithmic weight was first established by Calanchi and Ruf [J. Differential Equations 258 (2015), pp. 1967–1989]. The aim of this paper is to address the higher order version; more precisely, we show the following inequality
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="sup Underscript u element-of upper W Subscript 0 comma r a d Superscript 2 comma 2 Baseline left-parenthesis upper B comma omega right-parenthesis comma double-vertical-bar normal upper Delta u double-vertical-bar Subscript omega Baseline less-than-or-equal-to 1 Endscripts integral Underscript upper B Endscripts exp left-parenthesis alpha StartAbsoluteValue u EndAbsoluteValue Superscript StartFraction 2 Over 1 minus beta EndFraction Baseline right-parenthesis d x greater-than plus normal infinity">

sup

u
∈

W

0
,
r
a
d

2
,
2

(
B
,
ω
)
,

‖

Δ
u

‖

ω

≤
1

∫
B

exp
⁡

(

α

|
u
|

2

1
−
β

)

d
x
>
+
∞

\begin{equation*} \sup _{u \in W_{0,rad}^{2,2}(B,\omega ),{{\left \| {\Delta u} \right \|}_\omega } \le 1} \int _B {\exp \left ( {\alpha {{\left | u \right |}^{\frac {2}{{1 - \beta }}}}} \right )} dx > + \infty \end{equation*}

holds if and only if
\[

α
≤

α
β

=
4

[

8

π
2

(

1
−
β

)

]

1

1
−
β

,

\alpha \le {\alpha _\beta } = 4{\left [ {8{\pi ^2}\left ( {1 - \beta } \right )} \right ]^{\frac {1}{{1 - \beta }}}},

\]
where

B
B

denotes the unit ball in

R

4

\mathbb {R}^{4}

,

β
∈

(

0
,
1

)

\beta \in \left ( {0,1} \right )

,

ω

(
x
)

=

(

log
⁡

1

|
x
|

)

β

\omega \left ( x \right ) = {\left ( {\log \frac {1}{{\left | x \right |}}} \right )^\beta }

or

(

log
⁡

e

|
x
|

)

β

{\left ( {\log \frac {e}{{\left | x \right |}}} \right )^\beta }

, and

W

0
,
r
a
d

2
,
2

(
B
,
ω
)

W_{0,rad}^{2,2}(B,\omega )

is the weighted Sobolev spaces. Our proof is based on a suitable change of variable that allows us to represent the laplacian of

u
u

in terms of the second derivatives with respect to the new variable; this method was first used by Tarsi [Potential Anal. 37 (2012), pp. 353–385].
Completeness and separability of the spaces of variable integrability and summability
Authors: Ghorbanalizadeh Arash , Górka Przemysław
Published: February 2021

We address an open problem posed by Hästö in 2017 about separability of the mixed Lebesgue-sequence spaces

ℓ

q
(
⋅
)

(

L

p
(
⋅
)

)

\ell ^{q(\cdot )} (L^{p(\cdot )})

.
Torsion of elliptic curves with rational 𝑗-invariant defined over number fields of prime degree
Authors: Gužvić Tomislav
Published: February 2021

Let

[
K
:

Q

]
=
p

[K:\mathbb {Q}]=p

be a prime number and let

E

/

K

E/K

be an elliptic curve with

j
(
E
)
∈

Q

j(E) \in \mathbb {Q}

. We determine the all possibilities for

E
(
K

)

t
o
r
s

E(K)_{tors}

. We obtain these results by studying Galois representations of

E
E

and of its quadratic twists.
A note on congruences for weakly holomorphic modular forms
Authors: Dembner Spencer , Jain Vanshika
Published: February 2021

Let

O
L

O_L

be the ring of integers of a number field

L
L

. Write

q
=

e

2
π
i
z

q = e^{2 \pi i z}

, and suppose that
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="f left-parenthesis z right-parenthesis equals sigma-summation Underscript n much-greater-than negative normal infinity Endscripts a Subscript f Baseline left-parenthesis n right-parenthesis q Superscript n Baseline element-of upper M Subscript k Superscript factorial Baseline left-parenthesis upper S upper L 2 left-parenthesis double-struck upper Z right-parenthesis right-parenthesis intersection upper O Subscript upper L Baseline left-bracket left-bracket q right-bracket right-bracket">

f
(
z
)
=

∑

n
≫
−
∞

a
f

(
n
)

q
n

∈

M

k

!

(

SL
2

⁡
(

Z

)
)
∩

O
L

[
[
q
]
]

\begin{equation*} f(z) = \sum _{n \gg - \infty } a_f(n) q^n \in M_{k}^{!}(\operatorname {SL}_2(\mathbb {Z})) \cap O_L[[q]] \end{equation*}

is a weakly holomorphic modular form of even weight

k
≤
2

k \leq 2

. We answer a question of Ono by showing that if

p
≥
5

p \geq 5

is prime and

2
−
k
=
r
(
p
−
1
)
+
2

p
t

2-k = r(p-1) + 2 p^t

for some

r
≥
0

r \geq 0

and

t
>
0

t > 0

, then

a
f

(

p
t

)
≡
0

(
mod

p
)

a_f(p^t) \equiv 0 \pmod p

. For

p
=
2
,
3
,

p = 2,3,

we show the same result, under the condition that

2
−
k
−
2

p
t

2 - k - 2 p^t

is even and at least

4
4

. This represents the “missing case” of Theorem 2.5 from [Proc. Amer. Math. Soc. 144 (2016), pp. 4591–4597].
Uniqueness and stability of bistable waves for monotone semiflows
Authors: Zhang Yuxiang , Zhao Xiao-Qiang
Published: February 2021

This paper is devoted to the study of the uniqueness and stability of bistable traveling waves for monotone semiflows in an abstract setting. Under appropriate assumptions, we establish the uniqueness and stability of bistable waves for discrete and continuous-time semiflows in a continuous habitat by appealing to a global convergence theorem for monotone semiflows. We also extend such a result to time-periodic semiflows, and apply the general theory to a class of reaction-diffusion-advection systems in a cylinder.
Sets whose differences avoid squares modulo 𝑚
Authors: Ford Kevin , Gabdullin Mikhail
Published: February 2021

We prove that if

ε
(
m
)
→
0

\varepsilon (m)\to 0

arbitrarily slowly, then for almost all

m
m

and any

A
⊂

Z

m

A\subset \mathbb {Z}_m

such that

A
−
A

A-A

does not contain non-zero quadratic residues we have

|

A

|

⩽

m

1

/

2
−
ε
(
m
)

.

|A|\leqslant m^{1/2-\varepsilon (m)}.