bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the Biot–Savart law of electromagnetism applied to the atomic circulation current
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Authors: Hey J D 
Published: February 2021

Abstract
The law of Biot and Savart, derived by observation of the magnetic field produced by electric current flowing in a macroscopic conductor, is shown to yield the correct expression for the nuclear hyperfine interaction, when applied to the electron circulation current derived for hydrogenic atoms from the theories of Pauli and Dirac, as further developed independently by Darwin, Gordon and Hartree. The law thus applies also on the microscopic scale to the magnetic field generated by the electron probability flux of the various atomic eigenstates, and may clearly be generalised formally for application to many-electron atoms, as outlined by Hartree. The present, fully relativistic, treatment is advantageous in avoiding the usual artificial splitting of the hyperfine interaction into a magnetic dipole–dipole contribution and a separate contribution arising from electron orbital motion. The formula obtained forms the basis for the inclusion of higher order (quantum electrodynamic and nuclear recoil) corrections. Interest in this subject is enhanced by observations of ‘strongly forbidden’ (magnetic dipole) atomic transitions arising from the nuclear magnetic interaction, notably the 21 cm line of hydrogen, which has played an important role in astrophysics, in both measurements of galactic rotation and studies of the early Universe.
Work-Life Experiences of Women in the Construction Industry: A Case of Women in Lagos Mainland, Nigeria
Authors: Tunji-Olayeni P F , Kajimo-Shakantu K , Oni AA 
Published: February 2021

Abstract
The construction industry has not been able to maximize its full potentials in terms of harnessing the talents and abilities of its diverse workforce. Despite calls for a more pluralistic and inclusive workforce, the construction industry remains male-dominated, thereby limiting its growth potentials. The study examined the effects of workload on family expectations intending to support initiatives on gender equality and equity that will improve working conditions in the industry and eventually increase its performance and competitiveness. The study used questionnaires to achieve the research purpose. The survey was based on a purposive sampling of female construction professionals from different companies in Lagos Mainland, Nigeria. Descriptive statistics and linear regression were used for analysing the data. From the linear regression model, it was revealed that workload affects family responsibility at 73.20%. The significant family responsibilities affected by workload included: making alternative arrangements for children’s school transportation, spending time with spouse, spending time with children, taking care of household chores, and going shopping for the family. The study focused only on female construction professionals working in the Mainland area of Lagos, Nigeria. More empirical evidence of the effects of workload on family responsibilities can be obtained by considering female professionals in other regions of Nigeria. These findings have serious implications on job fulfilment, organizational loyalty, employee retention, and organizational performance. The study recommends flexible working hours and other gender-friendly policies to attain the much desired inclusive, profitable and sustainable construction industry.
The Covid-19 Pandemic: Online Teaching and Learning at Higher Education Institutes
Authors: Armoed Z 
Published: February 2021

Abstract
The most recent public health emergency of global concern has presented itself as the Covid-19 pandemic, which began in late 2019 Wuhan, China and has rapidly spread around the world. This disease has received extensive global attention due to the rapid rate of transmission between individuals, with the elderly easily affected. Countries, economies and sectors around the world faced immediate closure to mitigate the infection rate with scientists constantly searching for a means to eradicate the novel coronavirus disease (Covid-19). The education sector was one of the sectors significantly affected by the onset of the pandemic due the vulnerability of its setting. UNESCO (2020) reported that as of the 6th of April 2020, 1,576,021,818 billion students were affected across 188 countries at all levels of teaching and learning. As a result, the immediate implementation of online teaching and learning modalities were required with a primary focus on maintaining a standard of teaching and learning that met the needs of both academic staff and students. However, due to the socio-economic challenges faced by South Africans, the education sector experienced numerous challenges in the implementation process of online teaching and learning modalities (HEIs). This paper seeks to review the challenges experienced by academic staff and students with the implementation of online teaching and learning modalities at higher education institutes across South Arica amidst a global pandemic. Future research suggestions include a comprehensive research study on the extensive effects of the Covid-19 pandemic on higher education institutes.
Implication of BIM on selected aspects of sustainability
Authors: Mésároš Peter , Smetanková Jana , Mandičák Tomáš , Krídlová-Burdová Eva 
Published: February 2021

Abstract
Sustainability in civil engineering industry represents space for the subject of discussions and extensive research opportunities. On the other hand, this represents worldwide pressure to explore this area. Sustainability in the context of Building Information Modelling technology is also often a controversial topic. BIM technology brings many benefits. Exploring these technologies from the field of sustainability and environmental aspects is more than desirable in the light of global developments in this field. The aim of the research was to point out and propose a structure of environmental parameters based on the acquired knowledge, which will be incorporated into the emerging database of elements - information models. The paper presents a proposal for the structure of the database of structural elements taking into account cost parameters, time parameters, environmental parameters and life parameters, points out the main advantages of the proposed database and defines the aims of further research. The aim of the paper was to analyse the current state and possibilities of implication of certification systems for sustainable construction and describe the current state and impact of BIM implication on selected aspects by survey.
Advanced Treatment Process for Secondary Effluent of Municipal Wastewater Based on A/O Biological Filtration Technology
Authors: Zhengjiang Wang 
Published: February 2021

Abstract
Through the removal effects of the anoxic/oxic (A/O) biological filtration technology on organic matters, nitrogen and phosphorus, the advanced treatment for secondary effluent of municipal wastewater was analytically characterized by means of filter material selection and natural biofilm start-up. The results show that the composite slag has the best adsorbing effects on ammonia nitrogen and phosphorus, reaching 57% and 32.2%, respectively; as the natural biofilm start-up is smoothly implemented, the removal rate of ammonia nitrogen reaches over 60% in the first phase and over 96% in the second phase. This study provides a reference for the advanced treatment for secondary effluent of municipal wastewater.
Research on the Impact of Rooftop Photovoltaic on Reducing Carbon Dioxide Emissions
Authors: Tang Linyan 
Published: February 2021

Abstract
At present, the biggest environmental problem facing mankind is the rapid change of climate. In order to be able to mitigate climate change, we must attach importance to carbon reduction actions. China has taken many measures to adjust the energy structure to reduce petrochemical energy consumption and carbon emissions as much as possible. In the development of the power industry, the universal application of renewable resources such as solar energy can adjust and upgrade the traditional thermal power structure. The effective development of renewable resources such as solar energy can greatly reduce carbon dioxide emissions, which is an important measure to reduce carbon emissions. The establishment of solar photovoltaic power generation systems on the roof can improve the development level of China’s photovoltaic power generation systems. At the same time, this can also reduce the energy consumption of coal-fired power, which is of great help in reducing carbon emissions. In the process of researching rooftop photovoltaic power generation systems, we need to analyze the importance of solar photovoltaic power generation. Meanwhile, we also need to explore the practical application of rooftop photovoltaic power generation systems, and conduct research and analysis on the factors affecting rooftop photovoltaic carbon emission reductions. Only in this way can we accurately grasp the impact of rooftop photovoltaics on carbon dioxide emissions, and provide a corresponding reference for promoting the widespread application of rooftop photovoltaic power generation systems.
Application Research on Objective Evaluation of Vehicle Interior Odor Based On Weber-Fechner Law
Authors: Li Chuan Jie , Yao Qian , Liu Ya Lin , Wang Yan Meng , Feng Shi Hao 
Published: February 2021

Abstract
In this paper, four typical compounds of odorants were selected as the research objects. The mathematical model hypothesis is established which based on the Weber-Fechner law, and then the relationship between the concentration of odor substances and the odor grade is verified to judge whether this law is applicable to the objective evaluation of vehicle interior odor. The results show that: the concentration of single odor substance and odor grade, the concentration of two kinds of odor substances and odor grade are in accordance with this law. It is proved that the relationship between odor substance concentration and odor grade conforms to the law to a certain extent, which provides an important theoretical basis for objective evaluation of vehicle interior odor and control vehicle environment to create an environmental and healthy vehicle.
The influence of vegetation cover change on the land surface temperature in the central Guizhou urban agglomeration from 2000 to 2019
Authors: Sun Weizhao , Yang Kun , Luo Yi 
Published: February 2021

Abstract
We used land surface temperature (LST) and normalized difference vegetation index (NDVI) data from 2000 to 2019, using change trend analysis, correlation analysis, and other methods to explore the impact of vegetation cover changes on ground surface temperature. From 2000 to 2019, in the central Guizhou urban agglomeration, the LST showed a fluctuating downward trend, with an average trend rate of -5.1%a−1. NDVI showed a fluctuating upward trend, with an average trend rate of 0.56%a−1. The area with increasing LST (P<0.5) accounted for about 9.8%, and the area with a decreasing trend accounted for about 90.2%. The region of NDVI showing an increasing trend (P<0.5) accounted for approximately 97.34%, and the area of decreasing trend accounts for about 2.67%. About 96.8% of the regional area NDVI is negatively correlated with LST, and about 3.2% of the regional area is positively correlated.
Earthquake mechanism analysis of cross-faults system of Zhangjiakou-bohai fault belt in North China
Authors: Hong Li 
Published: February 2021

Abstract
North China is one of the earthquake-prone areas and Zhangjiakou-bohai belt is one of the main seismic tectonic belt in North China. There are many cross-faults in the belt and strong earthquakes occur at the intersection of faults. In order to explore the fault behavior and strong seismic mechanism of cross-fault system, we establish 3D finite element models to simulate the sliding activity of faults under the regional tectonic environment.
Analysis of Topographic Features Based on Yunnan Fire
Authors: Shangqi Duan , Haidong Chen , Xingke Ge , Shuangde Huang , Tao Wang , Debin Xu , Baoyu Xu 
Published: February 2021

Abstract
The Yunnan power grid has the characteristics of wide distribution and large geometric size, which makes the power grid vulnerable to natural disasters such as wildfires. The unique topography and climatic conditions of transmission lines crossing mountains, forests and other zones can easily lead to the outbreak of mountain fires, or even the tripping of transmission lines. In serious cases, transmission towers may be destroyed, thus causing major power accidents. The occurrence of mountain fire is closely related to topographic factors, and the change of each topographic factor (elevation, slope, slope direction, etc.) has a certain influence on fire. This paper mainly studies the relationship between three terrain factors and fire. Based on the statistical analysis of remote sensing data from 2005 to 2020, the terrain features and their influence of fire spots in Yunnan province were analyzed. The results show that most of the fires occur within the range of 1000-2000m above sea level, and the fires occur frequently. The frequency of fire occurring below 1000m and above 2000m is low. The occurrence frequency of fire is higher in the gentle slope range, among which, the number of fire point samples is the largest within the range of 5°-15°, followed by 0°-5°and less than 15°.In this paper, eight slopes are divided to make statistics of fire points, and the number of fires in different slopes also fluctuates, among which the south slope has the highest fire risk, accounting for 16.0%.The West Slope accounted for only 10.0%, with the lowest fire risk. Terrain factor is a fixed variable that has a fixed influence on the regional fire risk. Therefore, terrain analysis of fire is of great significance for the prevention of mountain fires in power grid.
Change trend analysis of the time-series shadow-eliminated vegetation index (SEVI) for the Wuyishan Nature Reserve with the Sen+Mann-Kendall method
Authors: Jiang Hong , Wu Yongfeng 
Published: February 2021

Abstract
In order to reveal the characteristics of spatial distribution and dynamic change of the forest in the Wuyishan Nature Reserve from 2000 to 2019, the recently proposed shadow-eliminated vegetation index (SEVI) and the method of Sen+Mann-Kendall were used together in this study. The results show a trend of “decreasing first and then increasing” of vegetation cover change of the Reserve during the sub-periods of 2000-2011 and 2012-2019, but, as a whole, the vegetation cover of the Reserve was improved during 2000-2019, with 43.76% slight improvement and 55.18% significant improvement, approximately.
Electromagnetic Signal from a Circumbinary Gas Disk Around Merging Binary Black Holes
Authors: Huang Zhuoyun , Yu Haoran 
Published: February 2021

Abstract
The detection of gravitational waves (GW) is a major achievement in physics and astrophysics. Up to now, more than 30 GW events resulting from the merger of compact celestial bodies have been observed by LIGO and VIRGO. Because electromagnetic radiation is the main method for studying astrophysical processes, whether physics can be combined with astronomy depends on whether the corresponding body of gravitational wave events can be found on electromagnetic radiation. Unfortunately, only the electromagnetic counterparts of the twin neutron star merger are currently seen. In gravitational wave astronomy, a very important subject is: Is it possible to generate electromagnetic radiation when the two black holes’ merge? In this essay, the dynamic process of the gas disk surrounding the binary black hole is studied through numerical simulation, and the long-term evolution process of these gases on the cosmological time scale is studied at the same time. The evolution process of the gas disk of the ring binary black hole can be obtained, which provides a theoretical limit on whether the electromagnetic counterpart of the merger of the binary black hole can be seen in the future.
Mineralogical characteristics of scheelite in the Xi’an tungsten deposit, western Hunan
Authors: Wen Jing , Zheng Shufen , Chu Xin , Jiang Han , Zhao Yurong 
Published: February 2021

Abstract
The Xi’an tungsten deposit, located in the middle of Xi’an gold antimony tungest metallogenic belt, western Hunan, is an important tungsten deposit in South China. In order to places emphasis on mineralogy of the scheelite, based on the previous researches, using mineralogical, this dissertation documents the geological feature of the studied deposit. This study investigated the scheelite deposit is hosted in the Madiyi Formation of Proterozoic Banxi Group. Its ore bodies, occurring as stratiform and stratoid, are strictly controlled by strata, lithology and structure. The chemical formula of scheelite collected from the studied deposit is Ca0.96W1.02O4.02, and its content of CaO is less than the theoretical value, while the content of WO3 is bigger, and the latter tends to increase with depth from deep to shallow. The crystal parameters for scheelite are close to the theoretical value.
In vitro Effect of Replacement Mineral Salts of Trace Elements with P-containing Chelates to Improve Rooting of Cherry Rootstock (cv. VC-13)
Authors: Tsirulnikova N V , Nikulina E A , Akimova S V , Kirkach V V , Glinushkin A P , Yu Podkovyrov I 
Published: February 2021

Abstract
In this paper, we studied the effect of modified culture medium based on Murashige and Skoog (Murashige T. Skoog F., 1962) on the in vitro rhizogenesis of clonal rootstock of stone cultures - VC-13. For the first time, the nutrient medium was modified with complexes of all incoming trace elements based on a phosphorus-containing ligand of the bisphosphonate class. The effect of 3 levels of concentrations of chelated trace elements was studied: 1.25, 2.5 and 5 ml/l without the use of increased doses of BMI, and a comparative analysis was carried out in comparison with the modification of trace elements based on EDTA. The maximum effect – 100% rooting after 30 days of subcultivation was found at a concentration of chelated trace elements of 5 ml/l. When modifying EDTA, rooting did not occur. Also, the modification of the nutrient medium by phosphorus-containing complexes contributed to a change in the nature of the formation of the root system of micro-gears. Micro-plants had from 3 to 6 short strong roots, convenient for washing from the nutrient medium and then planting at the stage of adaptation to non-sterile conditions. Repeated tests of the effect of culture medium modification on rhizogenesis in vitro on a larger scale confirmed the high efficiency of this approach. The rooting rate of micro-gears of the VC-13 clone rootstock was more than 80%. The results obtained allow us to conclude about the key role of the nature of the chelating agent.
SCREENING OF ENDOPHYTIC BACTERIA EXHIBITING ANTHAGONISTIC ACTIVITY AGAINST FUSARIUM SPOROTRICHIOIDES MICROMYCETE
Authors: Idiyatov I I , Tremasova A M , Tremasov Y M , Valiullin L R , Kalinitchenko V P , Rud V.Y. , Semenov A.M. 
Published: February 2021

Abstract
Within the framework of this study, the micromycete Fusarium sporotrichioides was isolated from wheat grain, a collection of isolates of endophytic microorganisms with antagonistic activity against this pathogen was formed, and their antagonistic activity was studied. By the mechanism of action, the isolates are classified as strains exhibiting fungistatic antibiotic antagonism, that is, inhibition of fungal growth occurred at a distance under the influence of antibiotic substances produced by the antagonist, with the formation of a “sterile” zone between cultures; and strains with fungistatic alimentary type of antagonism, expressed in stopping the growth of the pathogen upon contact with the antagonist colony. Stepwise screening of microorganisms-antagonists in in vitro and in vivo experiments made it possible to select technological and safe isolates with high antifungal activity and the possibility of using them as biofungicide producers. Three isolates from among the most active aboriginal endophytic microorganisms belonging to the species Bacillus subtilis are promising for introduction into the biocenosis with the aim of long-term regulation of the density of phytopathogenic populations of Fusarium sporotrichioides.
Study on the dynamic characteristics of the horizontally encrypted column network spring vibration isolated turbine-generator foundation
Authors: Song Yu Ying , Wang Xian Yun , Qu Tie Jun 
Published: February 2021

Abstract
To investigate the dynamic characteristics of the horizontally encrypted column network spring vibration isolated turbine-generator foundation, according to similarity theory, a 10:1 scale model of the horizontally encrypted column network spring vibration isolated turbine-generator foundation, including two condensers, was tested on site, and the dynamic characteristics of the model are analyzed by excitation method, and the natural frequencies, mode shapes and damping ratio of the integral structure are acquired. This study shows that the first two mode shapes of the turbine-generator foundation are translation and torsion, the high mode shape is accompanied by column-end swing and local distortion; the condenser is more stable in the integral structure; the natural frequency of this foundation is higher than the dual-row column spring vibration isolated turbine-generator foundation, and it is significantly lower than rigid foundation, and the mode shape distribution is different from them.
Preliminary Study of Ship Maneuvering Prediction of Container Ship
Authors: Yulianto A N , Aryawan W D , Putranto T , Sujiatanti S H , Ahadyanti G M , Purwanto D B 
Published: February 2021

Abstract
Ship maneuvering is defined as the inherent capability of a vessel to turn its path based on the hydrodynamics principles. The maneuvering performance becomes important to the safety of navigation when a ship operates. In case of vessel turning motion, International Maritime Organization (IMO) requires the maximum tactical diameter is five times of the ship lengths. Tactical diameter is the distance travelled by the ship’s center of gravity in a parallel direction to the ship’s initial path. In this paper, semi-empirical approach proposed by Clarke (1983) was used to obtain the first derivative of hydrodynamics equation. After that, the maneuvering performance was calculated using Son and Nomoto’s mathematical model (1981). Based on IMO regulations, the calculation of tactical diameter was conducted with 35° of rudder position. The calculation and analysis of tactical diameter was carried out according to relevant procedure of the ship maneuvering provided by IMO. The calculation result shows satisfactory result based on IMO regulations. The maximum tactical diameter does not exceed the requirements of IMO maneuvering standards. A further investigation was performed to see whether there was any impact on ship’s main dimensions to the maneuverability performance. In the future study, the development of open source software program to analyze the ship maneuvering performance is considered. It is expected to be able to contribute for facilitating in the preliminary ship design process.