bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on deformation of surrounding rock in fault tunnel based on field measured data statistics
Authors: Hao Chen
Published: January 2021

Based on the statistical analysis of surrounding rock deformation from 56 fault tunnels in China, the overall distribution characteristics and time evolution laws of surrounding rock deformation and the relationships with buried depth of tunnel and the height-span ratio are studied. The results of the statistical analysis show that the deformation is excessive when the tunnel passes through the fault zone. The average deformation value of surrounding rock in railway fault tunnels is maximum and second in highway fault tunnels and minimum in subway fault tunnels. The average value of peripheral convergence is larger than that of vault settlement. The deformation increases with the increases of buried depth, and the deformation in railway fault tunnels shows obvious concentration with the change of the height-span ratio. There is a significant time evolution law of surrounding rock deformation in fault tunnels, which can be roughly divided into three stages: rapid growth, slow growth and stabilization. The results offer some references for the optimal design of supporting structure and the reasonable construction time of secondary lining when the tunnels pass through the fault zone.
Comparative study on dam site selection in the pre-feasibility stage of Shitouzhai Hydropower Station
Authors: Shaohong Pan , Hongpin Zhang
Published: January 2021

The selection of dam site is the key content in the early stage of hydropower station project. Based on the hydrology, topographic and geological conditions, kinetic energy economic indexes, flood loss of reservoir, project layout, electromechanical and metal structure, construction conditions and project investment of the proposed dam site, this paper makes an in-depth analysis of the dam site selection in the pre-feasibility stage of Shitouzhai Hydropower Station, in order to provide beneficial inspiration for the design of similar projects.
Research on International New Industry Cooperation in the Core Area of Maritime Silk Road
Authors: FU LINGLAN , SU J. L.
Published: January 2021

This paper analyzes the main problems and difficulties faced by private enterprises in upgrading and upgrading in our province and explores the countermeasures for effectively accelerating the transformation and upgrading of private enterprises through several field investigations inside and outside the province. Through several provincial surveys and cross-provincial studies, the research group visited several typical private economic regions and their successful enterprises, explored their successful development experience and regional policy advantages, and put forward some countermeasures to accelerate the transformation and upgrading of private enterprises. Through investigation, the research group found that private enterprises in our province are facing problems in the new normal of economic development on private enterprises many impact; Through in-depth analysis and research, the research group puts forward the corresponding countermeasures, that is, accelerate the supply-side structural reform, and strive to provide beneficial policy advice and Suggestions for accelerating the transformation and upgrading of private enterprises in our province.This paper focuses on the research on international new industry cooperation in the core area of maritime silk road. FuJian is facing the main problems and difficulties in the international new industry cooperation. After thorough investigation and analysis, the research group put forward several feasible schemes.
NArchitecTURE: A Paradigm of Design with Nature
Authors: Ling Xiaohong
Published: January 2021

The relationship between architecture and nature has been a constant debate in the field. The preposition that architecture is an integral part of nature and even the natural landscape itself has accompanied the development of architectural theories over time. However, the question of how nature can be a design language intrinsically involved in the design process has not been systematically explored. This paper, therefore, through initiating the concept of NArchitecTURE, commences with a review of relevant theories concerning the relationship between nature and architecture. And then, through investigating a number of pioneering design works, this paper identifies a series of morphological types and spatial patterns that NArchitecTURE can produce. By means of proposing an alternative design paradigm by working with nature, this paper aims to provide contemporary architects with valuable inspiration to achieve environmental sustainability.
Research on the Characteristics and Regularity of Evacuation in Railway Tunnel Emergency Rescue Station at High Altitude
Authors: Xueling Liao , Qi Li , Xiangjie Min , Ruiwen He , Ruizhi Teng , Ruihua Zhang
Published: January 2021

With the development of economy, railway construction is gradually expanding to the plateau area, and the number of super-long railway tunnels at high altitude is increasing year by year. Compared with the plain area, due to the influence of hypoxia and panic, there are obvious differences in evacuation rules in plateau environment. In this paper, considering the high altitude environment, panic psychology, people’s age and gender and train structure factors, we use the Pathfinder personnel evacuation simulation technology, simulate and analyze evacuation of personnel in emergency rescue stations with different structural parameters. Finally we obtain the characteristics and rules of the evacuation of personnel in emergency rescue stations of high-altitude railway tunnels, and give the suggested design values of structural parameters of emergency rescue stations of high-altitude railway tunnels, so as to provide reference basis for its construction.
The influence and Thinking of urban planning on real estate development
Authors: Li Longhui
Published: January 2021

Since the reform and opening up, China’s rapid economic development, in this process, the construction industry or real estate industry is particularly rapid development. The rapid development of real estate industry has played a great role in promoting the urban construction of China. However, with the social and economic progress, China’s urban construction has been further expanded, with a more specific and detailed urban planning, so that the city can better serve the national construction. Similarly, urban planning also has an important impact on the development of real estate, and here we will explore how to better carry out the real estate development under the urban planning.
Composite control of the SiC arc welding power source based on the expert system and neuron PID
Authors: Si-min Chen , Qi-ming Zhong , Zhi-jing Zeng , Zhen-min Wang
Published: January 2021

A third generation wide-band-gap SiC semiconductor device is used in the SiC arc welding power source, which has a higher inverter frequency and greatly improves the dynamic characteristics of the arc welding power source, providing opportunities for control algorithm optimization. A composite control method of the arc welding power source combining the expert system and single neuron Proportional-Integral-Derivative (PID) is proposed in this paper, aimed at the fact that the proportional cofficient of neuron PID can hardly be adapted to rapid welding current changes. The SiC arc welding power source is taken as the plant of study in this paper. A mathematical model of the arc welding power source-arc system is established, and the controller of the arc welding power source based on the neuron PID and corresponding expert rules are defined to adjust the proportional coefficient of neuron PID Finally, the neuron PID controller (SNC) and the composite controller based on the expert system and neuron PID (ESNC) are simulated and verified. The results show that compared with the neuron PID algorithm, this method can adjust the proportional neuron PID coefficient in real time according to the welding current and has a better adaptive ability and superior tracking performance for arc welding power source control.
Hierarchical fuzzy obstacle avoidance control of omnidirectional mobile robot for substation inspection
Authors: Ma Li
Published: January 2021

There are some limitations in the practical application of robot obstacle avoidance control methods. In order to realize the high-speed planning and obstacle avoidance processing of mobile robot, the path model, inspection route and path obstacles of the robot must be fully considered. Through feature extraction, the reasonable planning of substation inspection obstacle avoidance route is realized, and the control quantity set satisfying substation inspection is given. The hierarchical fuzzy obstacle avoidance control method of mobile robot is realized by using the optimal control set design. The simulation results show that the control method can solve various complex problems when the robot contour collides with obstacles, and can realize safe and fast control. The flexibility and robustness of obstacle avoidance are improved, and the motion state and speed of obstacles are also improved.
The Friction and Wear Influence of Laser Processing Bionic Brake Drum Unit on the Brake Pad
Authors: Hu Haiyan , Yang Haiyang , Yang Jiandong , Wang Qingnian , Zhou Ti
Published: January 2021

This article starts with the analysis of the contact between the laser processing bionic brake drum unit body and the brake pad and performs the analysis of the force between the unit body and the brake pad based on elastic mechanics and contact mechanics. By using the Preston equation, the wear of the brake pad caused by the unit body is obtained, as well as the relevant factors and influence rule which affects the wear of the brake pad are found. During laser processing on the bionic brake drum unit body, in order to reduce wear of brake pad, the height of the unit body should be minimized. Besides, the light intensity at the centre of the laser spot should be reduced, and the laser intensity distribution should be more uniform, which can effectively improve the environmental friendliness of the brake drum.
Fault tolerant control of uav with wing layout based on control allocation
Authors: Jie Chen , Jianxin LIN
Published: January 2021

As the flying wing layout unmanned aerial vehicle (uav) extensive research and task environment increasingly complex, Yu Feiyi layout unmanned aerial vehicle (uav) for fault tolerant control gradually become the main technical means of the flight control, using the established mathematical model of the flying wing uav longitudinal layout setting the actuator failure effect, is in the nature of adaptive control allocation fault-tolerant algorithm is given, and MATLAB/simulink simulation is carried out for uav longitudinal motion, realize the rapid and stable, the control command and response to complete the nonlinear fault-tolerant control of flying wing uavs.
Research on Standardization of Aircraft Battle Damage Description
Authors: Jia Yang , Hanwu Zhao , Kai Guo
Published: January 2021

Rapid and accurate description of battle damage is the first step in aircraft battle damage repair (ABDR). The standardized description of damage information is the basis of the construction of aircraft battle damage data model. This paper studies and analyses the statistical description of battle damage in the view of definition, damage mode and cause classification of battle damage, so as to obtain the basis for standardized description of battle damage information.
Simulation Calculation of Air Conditioning System Under Complex Vehicle Conditions
Authors: Chang He , Cheng Lili
Published: January 2021

Based on the Simulink the vehicle air conditioning simulation platform for the whole vehicle is established. The multi model joint simulation system can predict the performance parameters and energy consumption of the air conditioning system under the conditions of different vehicle speed, temperature and humidity. It can coordinate the simulation of the temperature change process inside the passenger compartment with the performance of the air conditioning system.
Intelligent storage and washing integrated cabinet based on sine mechanism
Authors: Guo Pu , Shao Jiaxin , Tu Jiaqi , Xiong Xinhong
Published: January 2021

This smart storage and washing integrated cabinet based on sine mechanism mainly includes three functional modules: cleaning, storage and transportation. Each part of the organization to cooperate with each other to achieve three basic functions, such as no dead-end dishwashing, tableware storage and according to the instructions to take dishes. Not only that, it also enables additional functions such as drying disinfection and residue filtration. Now that intelligence is rapidly spreading, people’s hands in tableware management are free , Let people only participate in the beginning and end of the tableware management chain, and provide greater convenience to people’s lives.
Design and implementation of remote image processing system for space launch site
Authors: Li Ma , Yan Wang Bai , Tao Liu , Chao WangYu , Yu Xiang , Peng Li
Published: January 2021

Telemetry image has the characteristics of intuitive image in the process of rocket flight. Through real-time acquisition of rocket flight video image, it can provide the working status of key nodes in the process of rocket flight, and provide intuitive decision-marking auxiliary information for commanders. This paper analyzes the design content of the image processing system of the space launch site from the aspects of image transmission mechanism, information flow, image data processing and image decoding, so as to provide technical basis for the image receiving, transmission and decoding process in the engineering practice of the image processing system.
Pricing decision and coordination mechanism of dual-channel supply chain dominated by a risk-aversion retailer under demand disruption
Authors: Yan Bo , Chen Zhuo , Liu Yan-Ping , Chen Xiao-Xu
Published: January 2021

This paper studies a dual-channel supply chain composed of a retailer and a supplier, and discusses the optimal decisions of supply chain participants under decentralized decision-making without and with demand disruption, respectively. By comparing the optimal decisions in the two scenarios, we find that the optimal decision after demand disruption is a linear function of the demand disruption plus optimal decision before demand disruption. Additionally, when the demand disruption is in interval (−ψu2, ψu1), the optimal total production of the supply chain is equal before and after demand disruption. Moreover, the profits of the supply chain members and the value of their recognizing demand disruption are largely affected by the scale of demand disruption. Finally, the results show that the improved revenue-sharing contract can effectively improve the supply chain performance.
Hypergravity running: A “centrifugal track” for sprint-specific strength training
Authors: Picerno Pietro
Published: January 2021

After having discovered that, unlike humans, greyhounds do not slow down when running round a tight bend (Usherwood & Wilson, 2005 – https://doi.org/10.1038/438753a), desert lizards actually swim in the Sahara (Crofts & Summers, 2011 – https://doi.org/10.1038/472177a) and water strider insects are able to jump on water (Koh et al., 2015 – https://doi.org/10.1126/science.aab1637), we are now going to find out how sprint-running athletes can improve their strength capabilities by running under an augmented gravitational acceleration similar to that of Jupiter without actually having to leave Earth. The centrifugal track exploits the centripetal acceleration to increase the runner’s body weight during the foot-contact phase of running. Since inertial forces are distributed, the overload produced by running on the centrifugal track does not harmfully affect the musculoskeletal system. It has been shown that this overload does not cause acute detrimental changes to the running technique. The centrifugal track can be proposed as a viable alternative to traditional sprint-specific strength training tools.
Toward effective government communication strategies in the era of COVID-19
Authors: Hyland-Wood Bernadette , Gardner John , Leask Julie , Ecker Ullrich K. H.
Published: January 2021

Several countries have successfully reduced their COVID-19 infection rate early, while others have been overwhelmed. The reasons for the differences are complex, but response efficacy has in part depended on the speed and scale of governmental intervention and how communities have received, perceived, and acted on the information provided by governments and other agencies. While there is no ‘one size fits all’ communications strategy to deliver information during a prolonged crisis, in this article, we draw on key findings from scholarship in multiple social science disciplines to highlight some fundamental characteristics of effective governmental crisis communication. We then present ten recommendations for effective communication strategies to engender maximum support and participation. We argue that an effective communication strategy is a two-way process that involves clear messages, delivered via appropriate platforms, tailored for diverse audiences, and shared by trusted people. Ultimately, the long-term success depends on developing and maintaining public trust. We outline how government policymakers can engender widespread public support and participation through increased and ongoing community engagement. We argue that a diversity of community groups must be included in engagement activities. We also highlight the implications of emerging digital technologies in communication and engagement activities.
Velocity of suspended fluid particles in a low Reynolds number converging flow
Authors: Sangli Aditya N. , Bigio David I.
Published: January 2021

We studied a pressure-driven, low Reynolds number fluid flow through a planar channel whose spanwise width along the flow varied inversely as the streamwise coordinate such that the extensional rate on the centerline was near constant. The effect of the near constant extensional rate on an immiscible droplet of silicone oil was studied by tracking its deformation. The droplet rapidly deformed into an ellipsoid and displayed a consistent lag velocity compared to the single phase background flow at the same point. The observations were attributed to the flow induced deformation of the immiscible droplet, which was a function of the magnitude of the initial capillary number. The streamwise component of the single phase velocity along the centerline of the converging flow was also estimated as leading order using lubrication theory. The estimated velocity is compared favorably with numerical simulations; validation with experimental measurement of the flow of castor oil through the channel by tracking tracer particles is performed. The accuracy of the determination of the velocity field by the lubrication theory allowed for the careful measurement of the velocity difference between the drop and suspended fluid velocities. This research validated lubrication theory predictions of the flow velocity through a converging channel and provided an experimental insight into the behavior of a suspended phase.
High-frequency magnetotransport in La1-xSrxMnO3 (x = 0.12-0.20)
Authors: Chaudhuri U. , Mahendiran R.
Published: January 2021

We report the magnetization, magnetic field dependence of direct current magnetoresistance (dc MR) and alternating current magnetoresistance (ac MR) in La1-xSrxMnO3 (x = 0.12, 0.18, and 0.20) in the frequency range f= 30 MHz to 3000 MHz, at room temperature. The ac MR is negative in all three compositions and shows a dramatic increase in magnitude compared to the dc MR when f = 30 MHz and in a magnetic field H = ±3 kOe. With increasing frequency of current, the sign of ac MR at 3 kOe progressively changes from negative to positive in all these samples which is initiated by appearance of two peaks at H = ±Hr. Line shape analysis of the data indicate that Hr increases linearly with f in x = 0.12 and 0.18. We attribute the two peak behavior at high frequencies to electron paramagnetic resonance in x = 0.12 and 0.18 samples. From the analysis, we obtain the gyromagnetic ratio γ/2π = 2.428 MHz/Oe and 2.690 MHz/Oe for x = 0.18 and 0.12 respectively. The smaller value of γ/2π in x = 0.18 possibly reflects short-range correlations among Mn-spins in the paramagnetic state.
Electronic, magnetic and galvanomagnetic properties of Co-based Heusler alloys: Possible states of a half-metallic ferromagnet and spin gapless semiconductor
Authors: Semiannikova A. A. , Perevozchikova Yu. A. , Irkhin V. Yu , Marchenkova E. B. , Korenistov P. S. , Marchenkov V. V.
Published: January 2021

Parameters of the energy gap and, consequently, electronic, magnetic and galvanomagnetic properties in different X2YZ Heusler alloys can vary quite strongly. In particular, half-metallic ferromagnets (HMFs) and spin gapless semiconductors (SGSs) with almost 100% spin polarization of charge carriers are promising materials for spintronics. The changes in the electrical, magnetic and galvanomagnetic properties of the Co2YSi (Y = Ti, V, Cr, Mn, Fe) and Co2MnZ Heusler alloys (Z = Al, Si, Ga, Ge) in possible HMF- and/or SGS-states were followed and their interconnection was established. Significant changes in the values of the magnetization and residual resistivity were found. At the same time, the correlations between the changes in these electronic and magnetic characteristics depending on the number of valence electrons and spin polarization are observed.
Improved averaging of hysteresis loops from micromagnetic simulations of non-interacting uniaxial nanoparticles
Authors: Delgado-Garcia Rafael , Rodriguez-Rodriguez Gabriel , Colino Jose M.
Published: January 2021

Micromagnetic simulations allow us to understand the magnetization reversal of magnetic systems, but the computational cost scales up with the size and, in the case of bulk-scale systems, it becomes an impossible task to face unless certain assumptions are made (e.g. uniform and fully saturated magnetization or simplified anisotropy). However, those simplifications do not work for more complex systems with domain walls, shape anisotropy or exchange-bias. Macroscopic ensembles of non-interacting Magnetic Nanoparticles (MNP) can be modelled as an average of a set of isolated single-domain nanoparticles where magnetocrystalline anisotropies force the particle moments in a wide range of directions. To reduce computational time in such systems, we propose an optimized method of hysteresis loop averaging that takes advantage of high rotational symmetry of spherical particles and proves convenient for energy landscapes such as that in magnetocrystalline uniaxial systems. This improved method reduces the number of simulations required to generate macroscopic-like non-interacting and randomly oriented ensembles of magnetic nanoparticles (i.e. a dilute powder), as compared to the usual mean arithmetic averaging of hysteresis loops. To verify the good agreement of the averaging method we have compared our results with the well-known Stoner-Wohlfarth hysteresis loop, thus matching magnetic properties such as coercivity, remanence and energetic product with a relatively low count of simulations.
Reduction of magnetic noise limits of orthogonal fluxgate sensor
Authors: Dressler Michal , Janosek Michal , Butta Mattia
Published: January 2021

We have further lowered the white noise of an orthogonal fluxgate to about 0.3 pT/√Hz @ 8 Hz. So far, this is the lowest noise reported for a fluxgate magnetometer. The noise reduction was achieved by introducing a JFET input stage, embedded directly to the sensor head, allowing for high common-mode rejection and negligible loading of the resonant circuit. The origin of the noise was investigated by correlation measurements and we concluded that, at least in the white noise region, we observe the magnetic noise of the sensor, with about 0.1 pT/√Hz white noise contribution by the electronics. We were finally able to obtain sensor noise floor below 1 pT/√Hz @ 1 Hz also in a feedback-compensated closed-loop. Closed-loop operation allows for higher magnetometer stability and operation in Earth’s magnetic field without deteriorating its noise performance.
Preliminary comparison of skin transcriptome from sheep with different wool fibre diameters
Authors: Qi Yunxia , Fu Shaoyin , He Xiaolong , Wang Biao , Da Lai , Te Rigele , Yuejun Ma , Suzhen Sun , Zhang Wenguang , Liu Yongbin
Published: January 2021

Context Wool is one of the most important animal fibres for the textile industry, and its diameter directly affects its economic value. However, the molecular mechanisms underlying wool fibre diameter (FD) in sheep have not been fully elucidated. Aims The aims of the work were to make an initial comparison of skin transcriptomes from sheep with wool of high and low FD, and to identify key genes affecting FD. Methods High-throughput RNA-Seq technology was employed to explore the skin transcriptome, using three sheep with fine wool (FD <21.0 μm) and three sheep with coarse wool (FD >27.0 μm). Key results We obtained 28 607 228 bp of clean sequence data, 78.9% (±3.8%) of which uniquely aligned to the reference genome across the six samples. In total, 19 914 mRNA transcripts were expressed (FPKM >0) in the six skin samples, among which were certain well-known genes involved in the skin–hair cycle, such as KRTAP7-1, KRT14, Wnt10b, Wnt2b, β-catenin and FGF5. Furthermore, 467 genes were significantly differentially expressed between the fine-wool and coarse-wool groups, including 21 genes with upregulated and 446 genes with downregulated expression in the sheep with lower FD. These differentially expressed genes were particularly enriched in the gene ontology processes related to lipid metabolism, skin development, differentiation and immune function (P < 0.05). The biological processes were involved in collagen catabolism, negative regulation of macromolecule metabolism, steroid hormone stimulation and lipid metabolism. A significant Kyoto Encyclopedia of Genes and Genomes pathway involving the metabolism of lipids and lipoproteins was also enriched, revealing that lipid metabolism might be one of the key factors affecting FD. The expression of these differentially expressed genes that were involved in the metabolism of lipids and lipoproteins pathway was verified by quantitative real-time PCR (qPCR). The correlation between the mRNA expression level from qPCR and RNA-Seq data was 0.999 (P < 0.001). Conclusions The 467 differentially expressed genes, especially those involved in lipid metabolism and immune function, may play key roles in wool follicle metabolism and the expression of wool FD. Implications This study provided valuable data for future studies aimed at elucidating the mechanisms that underlie wool follicle metabolism and wool FD. The work may also have implications for studies of the human hair follicle.
Variability among Festuca arundinacea cultivars for tolerance to and recovery from waterlogging, salinity and their combination
Authors: Menon-Martínez F. E. , Grimoldi A. A. , Striker G. G. , Di Bella C. E.
Published: January 2021

Frequency and intensity of floods and the extent of salt-affected lands are expected to increase in pastures and grassland ecosystems as a result of global climate change. This study evaluated the effects of waterlogging, salinity (150 mm NaCl, ~15 dS m–1) and their combination over 14 days of treatment on morphological and growth traits of seven cultivars of Festuca arundinacea (tall fescue). Recovery was also assessed after a 14-day growth period under aerated, non-saline conditions (recovery phase). All cultivars survived the imposed stresses, showing greater tolerance to waterlogging than to salinity or the combined stress, evaluated as a response ratio of total dry mass relative to the control. The combined stress provoked growth lower than predicted by a multiplicative model in one cultivar, growth equal to the model in three cultivars and growth higher than the model in three cultivars. High variability among cultivars in response to each stress and phase was observed; this was more evident for relative growth rate of roots than of shoots. Plant morphological traits were affected by treatments in different ways; mature tiller weight was maintained, and tiller number decreased by 79–71% under waterlogging and combined stresses, whereas the opposite responses occurred under salinity. During the recovery phase, plants in all stress treatments had lower tiller numbers than controls and prioritised the growth of pre-existing tillers, which were heavier. Number of dead leaves per plant increased in saline and combined treatments. In general, F. arundinacea proved more tolerant to waterlogging than to salinity or combined treatments, and showed promising variability among cultivars with respect to root relative growth rate under the evaluated stresses, which can be used in future breeding programs. The findings also provide a basis for further research into the tolerance mechanisms involved.
Medium-term effects of straw helimulching on post-fire vegetation recovery in shrublands in north-west Spain
Authors: Fernández Cristina
Published: January 2021

Straw mulch is commonly applied to land after high-severity wildfires because of its effectiveness in reducing post-fire runoff and erosion. However, information about the effect on vegetation recovery is still scarce and usually limited to the first 2 years after wildfire. In this study, the effects of straw helimulching on vegetation recovery and species composition were assessed in 30 experimental plots established in four shrubland areas in north-west Spain 5 years after wildfire. The influence of the treatment on biomass accumulation in the medium term was also assessed. The relationships between soil burn severity, site characteristics (altitude, aspect, soil depth and percentage of stoniness) and the vegetation variables (total vegetation cover, weighted mean height of vegetation, total fuel load and litter and duff load) were also explored. Overall, the mulching treatment did not have significant effects on the variables studied. In the mulched plots, no non-native species were recorded 5 years after the wildfire. Site characteristics significantly affected the vegetation complex, but soil burn severity did not have any residual effect. The study findings indicate that straw helimulching has neutral effects on vegetation cover and composition in coastal shrublands in NW Spain in the medium term.
Multiscale modeling shows that dielectric differences make NaV channels faster than KV channels
Authors: Catacuzzeno Luigi , Sforna Luigi , Franciolini Fabio , Eisenberg Robert S.
Published: January 2021

The generation of action potentials in excitable cells requires different activation kinetics of voltage-gated Na (NaV) and K (KV) channels. NaV channels activate much faster and allow the initial Na+ influx that generates the depolarizing phase and propagates the signal. Recent experimental results suggest that the molecular basis for this kinetic difference is an amino acid side chain located in the gating pore of the voltage sensor domain, which is a highly conserved isoleucine in KV channels but an equally highly conserved threonine in NaV channels. Mutagenesis suggests that the hydrophobicity of this side chain in Shaker KV channels regulates the energetic barrier that gating charges cross as they move through the gating pore and control the rate of channel opening. We use a multiscale modeling approach to test this hypothesis. We use high-resolution molecular dynamics to study the effect of the mutation on polarization charge within the gating pore. We then incorporate these results in a lower-resolution model of voltage gating to predict the effect of the mutation on the movement of gating charges. The predictions of our hierarchical model are fully consistent with the tested hypothesis, thus suggesting that the faster activation kinetics of NaV channels comes from a stronger dielectric polarization by threonine (NaV channel) produced as the first gating charge enters the gating pore compared with isoleucine (KV channel).
Quasi binormal Schrodinger evolution of wave polarizatıon field of light wıth repulsive type
Authors: Korpinar Talat , Demirkol Rıdvan Cem , Khalil Eied M , Korpinar Zeliha , Baleanu Dumitru , Inc Mustafa
Published: January 2021

In this paper, we study the evolution of the wave polarization vector in the tangent direction of the curved path. This path is assumed to be the trajectory of the propagated light beam. The polarization state of the wave is described by the unit complex transverse field component by eliminating the longitudinal field component. We obtain new relationship between the geometric phase and the parallel transportation law of the wave polarization vector of the evolving light beam in the tangent direction of the curved path. Moreover, we present a new geometric interpretation of the quasi binormal evolution of the wave polarization vector via the nonlinear Schrodinger equation of repulsive type in the tangent direction. Finally, we find a space-time nonlocal NLS reduction for equation system.
Perturbation, symmetry analysis, Bäcklund and reciprocal transformation for the extended Boussinesq equation in fluid mechanics
Authors: Wang Gangwei , Wazwaz Abdul-Majid
Published: January 2021

In this work, we study a generalized double dispersion Boussinesq equation that plays a significant role in fluid mechanics, scientific fields, and ocean engineering. This equation will be reduced to the Korteweg–de Vries equation via using the perturbation analysis. We derive the corresponding vectors, symmetry reduction and explicit solutions for this equation. We readily obtain Bäcklund transformation associated with truncated Painlevé expansion. We also examine the related conservation laws of this equation via using the multiplier method. Moreover, we investigate the reciprocal Bäcklund transformations of the derived conservation laws for the first time.
Origin of hardening in spectra of cosmic ray nuclei at a few hundred GeV using AMS-02 data *
Authors: Niu Jia-Shu
Published: January 2021

Many experiments have confirmed spectral hardening at a few hundred GeV in the spectra of cosmic ray (CR) nuclei. Three different origins have been proposed: primary source acceleration, propagation, and the superposition of different kinds of sources. In this work, a broken power law has been employed to fit each of the spectra of cosmic ray nuclei from AMS-02 directly, for rigidities greater than 45 GeV. The fitting results of the break rigidity and the spectral index differences less than and greater than the break rigidity show complicated relationships among different nuclear species, which cannot be reproduced naturally by a simple primary source scenario or a propagation scenario. However, with a natural and simple assumption, the superposition of different kinds of sources could have the potential to explain the fitting results successfully. Spectra of CR nuclei from a single future experiment, such as DAMPE, will provide us the opportunity to do cross checks and reveal the properties of the different kinds of sources.
Experiment and simulation of ELM in NBI heated plasma on EAST tokamak
Authors: Geng K.N. , Tang T.F. , Kong D.F. , Zhang S.B. , Zhang T. , Huang C.B. , Wu M.Q. , Jiang D. , Lyu B. , Wang L. , Gao W. , Liu Z.X. , Liu A.D. , Duan Y.M. , Zhang L. , Jie Y.X. , Zang Q. , Zhu X. , Hao B.L. , Wang K. , Lin X.D. , Huang J.J. , Wan Y.X. , Gao X.
Published: January 2021

By scanning toroidal rotation with a combination of co- and counter-current direction neutral beam injection (NBI) on the Experimental Advanced Superconducting Tokamak, it is found the size of edge localized mode (ELM) decreases with increasing toroidal rotation in counter-current direction. The synergistic effect of plasma rotation and collisionality on ELM behavior is also studied by statistical analysis. Three-field module in BOUT++ framework is employed to study the impacts of toroidal rotation/E × B flow shear on ELM behaviors. The BOUT++ simulation results show that both Co- and Ctr-NBI induced net flow have stabilization effects on the peeling-ballooning modes, especially for counter NBI case, high-n ballooning mode can be totally stabilized. With larger E × B shear, the mode number of most unstable mode downshifts in the counter NBI case, with larger E × B shear, the mode number of most downshifts in the counter NBI case, correlated with reduced ELM size.
The Development of Learning Design for Polyhedron Based On Realistic Mathematic Education for Grade VII of Junior High School Students
Authors: Prestiani V , Irwan  , Arnawa I M
Published: January 2021

The flow of teaching mathematics on the topic of Polyhedron all this time emphasizes memorization of formulas and the provision of exercises to students which are still teacher-centered. Learning design is needed to facilitate students to actively participate in building the concept of building a flat-sided class room in grade VIII of Junior High School based on Realistic Mathematic Education using the learning flow in the form of Hypothetical Learning Trajectory and implementation products in the form of teacher books and student books. This type of research was development research that combines two types of research design, namely the Plomp and Gravemeijer and Cobb models which consist of three phases: preliminary research, development or prototyping and assessment phases. This research was limited to preliminary research. Teacher interview guidelines, student interview guidelines, field notes, preliminary test questions for students' mathematical reasoning abilities are used as instruments. From this preliminary research phase, it could be concluded as follows: (1) teachers are guided by printed books owned by teachers and students, which have not facilitated students to develop concepts through meaningful learning activities, (2) teachers also had not designed learning paths which was appropriate for teaching a mathematical topic, (3) the mathematical reasoning ability of students was not optimal, (4) the preparation of the learning flow was in accordance with the results of curriculum analysis.
The Role of Mathematics Anxiety and Mathematical Problem-Solving Skill
Authors: Rusyda N A , Suherman  , Dwina F , Manda T G , Rusdinal R
Published: January 2021

The purpose of this research is to analyze the correlation between mathematics anxiety and mathematical problem-solving skill. The data was collected by using a mathematics anxiety questionnaire and a problem-solving test. There were seven questions for the test of mathematical problem-solving and 25 questions for the mathematics anxiety questionnaire. The questionnaire was arranged by using the Likert Scale. The data were analyzed using the Pearson correlation formula. The population is the students in the calculus class. The samples are 200 students that were chosen by using a purposive random sampling technique. The results showed that there was a negative correlation between mathematics anxiety and mathematical problem-solving.
The Effect of Problem Based Module for Sampling Technique Courses Toward College Student Problem Solving Behaviour; Case Study in Indonesia
Authors: Harisman Y , Sovia A , Rahima
Published: January 2021

This study aims to look at the effectiveness of problem-based modules in lectures on Sampling Techniques toward problem-solving behavior. A module can also be used by using an e-learning platform if the lecturer cannot face-to-face because the modules designed can be used independently by college students because they contain material, examples, guided exercises, independent exercises, and answer keys. The subjects of this study were 26 college students from one of the private universities in Indonesia. The study used a One-Shot Case Study design. Data collection is done through a final Problem-Solving test, open interview, video analysis. Data were analyzed using a t-test and problem-solving behavior rubric. Based on the results of the study concluded that was the use of the Sampling Technique module in lectures affected college student problem-solving behavior. This means that the problem-based sampling technique module is effectively used in studies.
Analysis of Students Mathematical Concept Understanding Ability in Operation Research Course
Authors: Manda T G , Winanda R S , Rusyda N A
Published: January 2021

The purpose of this research to improve the students' mathematical concept understanding ability who receive the Scientific approach with PBL model learning compared to students who receive conventional learning in operation research courses through pretest. The sample was two classes of 2019 who took an operation research course. The data was analyzed by quantitative technique. The result of the research base on the pretest explained that it is known that the students' mathematical concept understanding ability is low.
The Used of E-learning Based on Android in Actuarial Courses
Authors: Suherman  , Fauzan A , Yerizon
Published: January 2021

This research is advance research that built an android application for the lecture process in e-learning for actuarial courses. This research aims to produce the learning designs to apply the applications developed in Actuarial courses. The product developed is a compilation of Semester Lecture Plans, Lecture Program Units, teaching materials, and queries. This research produced an android application program for e-learning in Actuarial lectures at the Mathematics Education Study Program Department of Mathematics, Faculty of Mathematics and Natural Sciences, UNP Padang.
The Development of Student Worksheet Based on Realistic Mathematics Education in Ordinary Differential Equations of Order-1
Authors: Yarman  , Fauzan A , Armiati  , Yerizon  , Lufri
Published: January 2021

Students' mathematical communication skills are still low and need to be improved. Learning tools do not support the student learning process. This study aims to produce a learning trajectory for lst-order differential equations. This type of research is a Plomp type research design consisting of three phases: (1) preliminary phase (preliminary research phase), (2) prototyping phase (prototype development phase), and (3) assessment phase (assessment phase). This section reports the preliminary phase. The conclusion is that the device has not facilitated students to make their own strategies to find concepts. Students need teaching materials in the form of worksheets that contain contextual problems that are close to students and facilitate student learning flow in rediscovering the theoretical concept of Ordinary Differential Equations (ODE).
On Locating Chromatic Number of H = Pm
∪ Wn
Authors: Anti A. , Welyyanti D. , Azhari M.
Published: January 2021

A married of vertex coloring partition and dimension of graph, became a definition of locating chromatic number of graph. That draught only can apply for connected graph. Because that, Welyyanti et al. expand concept of the locating chromatic number for disconnected graph. For this paper, the locating-chromatic number of disconnected graph contains one path and wheel graph as its components, is determined.
Development of constructivism-based mathematics interactive learning media tools on the material of constructing a flat side space for class VIII junior high school students
Authors: Rullis R M , Fauzan A
Published: January 2021

This study originated from students who had difficulty understanding the material of flat-sided shapes. Students often make mistakes in solving flat-sided shapes, including errors in calculations, and students having difficulty in visualizing images, especially in the material of flat-sided shapes. Also, many students still entered the formula incorrectly. One way to overcome this problem is to develop media-based interactive learning with a constructivist approach. This study aims to produce constructivism-based interactive mathematics learning media that is valid and practical on flat-sided building materials for class VIII junior high school students. This study describes the effectiveness of constructivist-based interactive learning media that is valid and practical flat-sided building materials for junior high school students VIII. The type of research used is development research using the Plomp model, which consists of three phases: the initial investigation phase, the development phase or prototyping, and the assessment phase. The preliminary research needs analysis, curriculum analysis, student analysis, and concept analysis were carried out. At the stage of developing or making a prototype, the researcher designs constructivism by paying attention to content, language, presentation, and graphics. Media-based interactive learning constructivism is validated by experts in mathematics, media, technology, and language education. Practicality is seen through the analysis of the implementation of learning observations, interviews, and student and teacher response questionnaires. Effectiveness is seen through the results of the analysis of student activities and learning outcomes.
The practicality of learning design based on realistic mathematics education for probability topic of grade VIII junior high school
Authors: Sya’bani F , Armiati  , Permana D , Arnawa I M , Asmar A
Published: January 2021

This study aimed to determine the practicality of Realistic Mathematics Education (RME) based learning design for probability topics. Probability is a learning topic that is close to daily life and is expected to assist students in developing students' communication skills. The Learning design development was done by combining two designs, namely the development design of Plomp and Gravemeijer & Cobb; meanwhile, to find out the practicality of the design, data collection was done in the form of filling out questionnaires by teachers and students. The data obtained were analyzed quantitatively and qualitatively. From the research conducted, it was obtained that the RME-based learning design for the topic of Probability was practical so that the RME-based learning design of probability topics that were implemented to teacher books and student books could be used to develop mathematical communication skills of grade viii junior high school students.
Study of factors affecting student learning outcomes in Real Analysis lectures during the Covid-19 pandemic
Authors: Helma H , Murni D
Published: January 2021

The competencies to be achieved in the Real Analysis course are 1) prove simple math statements with familiar concepts and 2) develop critical, creative, structured, and systematically thinking skills. This competence can be improved by using flow proof-based teaching materials and direct interaction in class between lecturers and students. During the Covid-19 pandemic, direct interaction in class was replaced with online learning. Of course, online interactions will affect student learning outcomes. What are the factors that affect student learning outcomes in real analysis lectures during the Covid-19 pandemic? By using a questionnaire, data about these factors were obtained. The factors affecting of learning outcomes during the Covid-19 pandemic are student background, learning attitude, and learning style. In particular, the indicators that influence student learning outcomes are the ease of obtaining internet access, the need for time to study that is not in accordance with the schedule, not confident in solving Real Analysis problems/exercises, not being able to understand Real Analysis material independently, and student learning styles.