bluuebunny/crossref_metadata_2025 huggingface dataset:
Elastic properties assessment in the multiferroic BiFeO3 by pump and probe method
Authors: Hemme Pierre , Djemia Philippe , Rovillain Pauline , Gallais Yann , Sacuto Alain , Forget Anne , Colson Dorothée , Charron Eric , Perrin Bernard , Belliard Laurent , Cazayous Maximilien
Published: February 2021

We have performed elasticity measurements in the bulk multiferroic BiFeO3 (BFO) using acoustical pump and probe spectroscopy. The sound velocities of the (quasi)-longitudinal and two (quasi)-transverse acoustic waves along three independent directions of the (110) surface have been measured. Moreover, one surface wave and one longitudinal wave propagating perpendicular to the surface have been detected. Based on initial input values of the six independent Cij elastic constants determined by our density functional theory calculations and our eleven experimental velocities, the numerical resolution of the acoustic equations allows us to determine all the Cij elastic constants of BFO. The propagation direction dependence of volume and surface waves phase velocities allows the unambiguous assignment of the waves and, hence, the polarization of phonons.
Local non-linear excitation of sub-100 nm bulk-type spin waves by edge-localized spin waves in magnetic films
Authors: Gruszecki Pawel , Lyubchanskii Igor L. , Guslienko Konstantin Y. , Krawczyk Maciej
Published: February 2021

The excitation of high-frequency short-wavelength spin waves is a challenge limiting the application of these propagating magnetization disturbances in information processing systems. We propose a method of local excitation of the high-frequency spin waves using the non-linear nature of magnetization dynamics. We demonstrate with numeric simulations that an edge-localized spin wave can be used to excite plane waves propagating obliquely from the film's edge at a doubled frequency and over twice shorter in wavelength. The excitation mechanism is a direct result of the ellipticity of the magnetic moment precession that is related to the edge-mode propagation. As a consequence, the magnetization component tangential to the equilibrium orientation oscillates with doubled temporal and spatial frequencies, which leads to efficient excitation of the plane spin waves. The threshold-less non-linear process of short-wavelength spin-wave excitation proposed in our study is promising for integration with an inductive or point-like spin-torque source of edge spin waves.
Broadband sound attenuation by metaliner under grazing flow
Authors: Huang Sibo , Zhou Enmin , Huang Zhilong , Lei Pengfei , Zhou Zhiling , Li Yong
Published: February 2021

Acoustic liners are the most effective passive solution to noise emission from ducts but still suffer from the drawbacks of narrow-band performances and thick structures for the conventional designs. Here, we present an acoustic metaliner capable of high-efficiency broadband sound attenuation under grazing flow. The metaliner is composed of a perforated plate and a metasurface consisting of a series of neck-embedded Helmholtz resonators (NEHRs). By tuning the nonlocal coupling among the NEHRs and the perforated plate, efficient broadband impedance modulation can be realized, leading to a strong dissipation of broadband sound energy under various speeds of grazing flow. We theoretically and experimentally investigate a well designed metaliner, which can strongly attenuate sound energy for a wide frequency range from 800 Hz to 3000 Hz, both in the absence of air flow and in the presence of grazing flows with speeds from 10 m/s to 60 m/s. Besides, the thickness of the metaliner is only 40.5 mm. Our work provides a route to reduce flow-related noise in a broad frequency range and may find applications in airplane propulsion systems, air-conditioning systems, and other mechanical systems with flow.
Effects of content-based instruction (CBI) on EFL secondary school learners’ writing
Authors: Suzuki Noriko
Published: February 2021

To investigate the impact of meaning-focused content-based instruction (CBI) and language-focused non-CBI, both dealing with compare/contrast language, this study compared Japanese secondary school students’ compare/contrast writing on two topics (i.e., a power generation topic aligned to the CBI and a new topic) in pre-and post-tests. Their writing was analyzed in terms of complexity, accuracy, fluency, and functional adequacy. The results show that the CBI group improved both linguistic and functional aspects of the power generation topic, as well as two functional aspects of the new topic. In contrast, the non-CBI group showed two linguistic changes in the power generation topic, and three linguistic and two functional changes in the general topic writing. Therefore, CBI may not only serve to improve linguistic and functional aspects on the same topic writing but also might draw writers’ attention to functional aspects in a new topic.
Objective and subjective collocational frequency
Authors: Cangır Hakan
Published: February 2021

Research states that when deciding what target lexical items to focus in their syllabi, textbook designers tend to use their intuition and establish their framework for vocabulary teaching accordingly rather than using a systematic method. With the advent of computational methods for language analysis, contemporary EFL publishers also claim they have begun to design corpus-informed textbooks reflecting actual language use in their products as evidenced in a representative corpus. In an attempt to offer a more rational method to form corpus-oriented and pedagogically convenient target vocabulary lists, the present study, exploiting different association measures in a representative corpus, seeks to detect the collocational strength of 50 target word combinations presented in the two EFL textbooks as an initial step. Additionally, inspired byEllis et al.’s (2008)research, the current study aims to investigate if/to what extent the association measures indicating collocational strength correlate with EFL instructors’ intuitions regarding collocational frequency. The results indicate that EFL instructors’ collocational frequency intuitions correlate strongly with an objective collocational frequency measure (t-score). The findings are likely to guide decision makers in tertiary level schools in constructing their vocabulary syllabi and designing materials for teaching collocations in particular.
Near ambient pressure photoelectron spectro-microscopy: from gas–solid interface to operando devices
Authors: Amati Matteo , Gregoratti Luca , Zeller Patrick , Greiner Mark , Scardamaglia Mattia , Junker Benjamin , Ruß Tamara , Weimar Udo , Barsan Nicolae , Favaro Marco , Alharbi Abdulaziz , Jensen Ingvild J T , Ali Ayaz , Belle Branson D
Published: February 2021

Near ambient pressure scanning photoelectron microscopy adds to the widely used photoemission spectroscopy and its chemically selective capability two key features: (1) the possibility to chemically analyse samples in a more realistic gas pressure condition and (2) the capability to investigate a system at the relevant spatial scale. To achieve these goals the approach developed at the ESCA Microscopy beamline at the Elettra Synchrotron facility combines the submicron lateral resolution of a Scanning Photoelectron Microscope with a custom designed Near Ambient Pressure Cell where a gas pressure up to 0.1 mbar can be achieved. In this manuscript a review of experiments performed with this unique setup will be presented to illustrate its potentiality in both fundamental and applicative research such as the oxidation reactivity and gas sensitivity of metal oxides and semiconductors. In particular, the capability to perform operando experiments with this setup opens the possibility to study operating devices and to properly address the real nature of the studied systems, because if microscopy and spectroscopy are simultaneously combined in a single technique it can yield to more conclusive results.
Measurement outcomes that do not occur and their role in entanglement transformations
Authors: Hebenstreit Martin , Englbrecht Matthias , Spee Cornelia , de Vicente Julio I. , Kraus Barbara
Published: February 2021

The characterization of transformations among entangled pure states via local operations assisted by classical communication (LOCC) is a crucial problem in quantum information theory for both theoretical and practical reasons. As LOCC has a highly intricate structure, sometimes the larger set of separable (SEP) maps is considered, which has a mathematically much simpler description. In the literature, mainly SEP maps consisting of invertible Kraus operators have been taken into account. In this paper we show that the consideration of those maps is not sufficient when deciding whether a state can be mapped to another via general SEP transformations. This is done by providing explicit examples of transformations among pure three- and five-qubit states, which are feasible via SEP maps containing singular Kraus operators, however, not possible via SEP maps containing solely regular Kraus operators. The key point that allows to construct the SEP maps is to introduce projective measurements that occur with probability zero on the input state. The fact that it is not sufficient to consider SEP maps composed out of regular Kraus operators even in the case of pure state transformations, also affects the results on LOCC transformations among pure states. However, we show that non-invertible Kraus operators do not help in state transformations under LOCC with finitely many rounds of classical communication, i.e. the necessary and sufficient condition for SEP transformations with invertible Kraus operators is still a necessary condition for convertibility under finite-round LOCC. Moreover, we show that the results on transformations via SEP that are not possible with LOCC (including infinitely many rounds of classical communication) presented in Hebenstreit et al 2016 Phys. Rev. A
93, 012339 are not affected.
Gravitational energy of the spherically symmetric static and charged black holes encircled by the dark energy through approximate Lie symmetries
Authors: Liaqat Asia , Hussain Ibrar
Published: February 2021

We investigate the gravitational energy of the Reissner-Nordström black hole encircled by dark energy using the approach of approximate Lie symmetries of second-order. We confine our calculations to following values of the equation of state parameter ω: (i)

ω

q

=
−

1

2

(quintessence regime of dark energy), (ii) ω
Λ = −1 (the pure cosmological constant regime), (iii)

ω

c

=
−

1

3

(frustrated cosmic strings network). In order to examine the gravitational energy for the Reissner-Nordström black hole spacetime encircled by the dark energy, we construct a system of second-order perturbed geodesic equations, which is done primarily by considering the mass M and charge Q of the black hole in terms of some small perturbation parameter ϵ. It is observed that we do not obtain any non-trivial approximate symmetry generator for any value of the state parameter ω, we get only trivial second-order approximate symmetry generators. As a result of these trivial approximate symmetries we get a rescaling of the proper time s which gives the rescaling of energy in the Reissner-Nordström spacetime encircled by the dark energy. It is found that for

ω

q

=
−

1

2

and ω
Λ = −1, the rescaling factor for energy is dependent on r and for

ω

c

=
−

1

3

, the rescaling factor is independent of the radial distance r. Furthermore, we investigate that the effect of cosmological constant and quintessence dark energy decreases the energy of the underlying spacetime while the equation of state parameter

ω

c

=
−

1

3

, for which the Universe is static, increases the energy of the Reissner-Nordström black hole spacetime encircled by the dark energy.
Improvements on spatial coverage and focality of deep brain stimulation in pre-surgical epilepsy mapping
Authors: Collavini Santiago , Fernández-Corazza Mariano , Oddo Silvia , Princich Juan Pablo , Kochen Silvia , Muravchik Carlos H
Published: February 2021

Objective.Electrical stimulation mapping (ESM) of the brain using stereo-electroencephalography (SEEG) intracranial electrodes, also known as depth-ESM (DESM), is being used as part of the pre-surgical planning for brain surgery in drug-resistant epilepsy patients. Typically, DESM consists in applying the electrical stimulation using adjacent contacts of the SEEG electrodes and in recording the EEG responses to those stimuli, giving valuable information of critical brain regions to better delimit the region to resect. However, the spatial extension or coverage of the stimulated area is not well defined even though the precise electrode locations can be determined from computed tomography images.Approach.We first conduct electrical simulations of DESM for different shapes of commercial SEEG electrodes showing the stimulation extensions for different intensities of injected current. We then evaluate the performance of DESM in terms of spatial coverage and focality on two realistic head models of real patients undergoing pre-surgical evaluation. We propose a novel strategy for DESM that consist in applying the current using contacts of different SEEG electrodes (x-DESM), increasing the versatility of DESM without implanting more electrodes. We also present a clinical case where x-DESM replicated the full semiology of an epilepsy seizure using a very low-intensity current injection, when typical adjacent DESM only reproduced partial symptoms with much larger intensities. Finally, we show one example of DESM optimal stimulation to achieve maximum intensity, maximum focality or intermediate solution at a pre-defined target, and one example of temporal interference in DESM capable of increasing focality in brain regions not immediately touching the electrode contacts.Main results.It is possible to define novel current injection patterns using contacts of different electrodes (x-DESM) that might improve coverage and/or focality, depending on the characteristics of the candidate brain. If individual simulations are not possible, we provide the estimated radius of stimulation as a function of the injected current and SEEG electrode brand as a reference for the community.Significance.Our results show that subject-specific electrical stimulations are a valuable tool to use in the pre-surgical planning to visualize the extension of the stimulated regions. The methods we present here are also applicable to pre-surgical planning of tumor resections and deep brain stimulation treatments.
The study of radiation effect on Raman Distributed optical fiber Temperature Sensor
Authors: Xiang Meiqiong , Liu Yanyang , Qing Xianguo , He Zhengxi , Zhu Jialiang , He Peng , XinLv
Published: February 2021

The rapid development of big data and artificial intelligence technology is inseparable from the acquisition of massive basic data, and the data is acquired by sensors. The Raman Distributed optical fiber Temperature Sensor (RDTS) is a kind of sensor with many advantages, such as: anti-electromagnetic interference, intrinsic safety, small size, water and high temperature resistance. It has been applied in many fields for fast and continuous temperaturemeasurement. However, due to the rapid attenuation of transmitted light and the temperature error in radiated environment, it has not been applied innuclear field. Therefore, in order to improve the temperature accuracy of RDTS in radiated environment and provide basic data for advanced control. This paper studies the radiation effect on RDTS. Analyzesthe radiation damage mechanism and radiation damage influencing factors of RDTS. Proposes measures to improve the anti-radiation performance and provides four useful calibration methodsfortemperature error. Among them, two calibration methods have been proved right by experiments.
Design of a novel grinding end-effector for spiral welded pipe
Authors: Ayalew Getachew Demeissie , Zheng Yu , Yang Yang
Published: February 2021

In the spiral welded pipe manufacturing process, grinding is one of the production processes, this process proceeds by hand grinding and fixed machine grinding. Usually, those methods have impacts larboard intensive, long production cycle and unstable product qualification rate for the final product. To prevent those factors from this paper, present a newly-designed grinding machine for a spiral welded pipe manufacturing industry, the machine has equipped with a special grinding machine with the ability to grind the spiral welded pipe the inner and outer surface simultaneously of the pipe and equipped with 6DOF grinding robot. The kinematics model of grinding robot is derived and the robot joint trajectory is calculated. The simulation result shows that the grinding mechanism can perform the job without failures under the external torque, and also trajectory graph of the robot kinematics shows there is no vibration on the robot movement to perform the job.
Case studies in modular prefabrication: comparative analysis and discoveries
Authors: Gharehbaghi Koorosh , Mulowayi Erica , Rahmani Farshid , Paterno David
Published: February 2021

While prefabrication is the process where parts are manufactured off-site, modular construction on other hand is the utilisation of parts along with their installation to form a complete structure, such as a building. The aim of this paper is to compare case studies in prefabrication including modular construction. Subsequently, this paper reviewed five case studies around the globe. The comparison of these case studies showed that China had the fastest construction rate by manufacturing steel modules off-site. This was presumably due to the significant use of Advanced Modular Technology (AMT). Such new technique can potentially be the next era of prefabrication construction in high-rise construction. Particularly, the corporations which are either exploring or are using modular prefabrication should utilise AMT to enhance the design technique and assembly of prefabricated units.
An estimation procedure with knot selection for multivariate regression splines
Authors: Huang Tzee-Ming
Published: February 2021

Knot selection for regression splines is crucial to the approximation power of splines. For univariate splines, many knot selection algorithms are available. However, extending those univariate algorithms to the multivariate case can be challenging. In this work, an estimation procedure with knot selection for multivariate regression splines is proposed, where the knot selection part is adapted from an existing univariate knot selection algorithm. Simulation results are included to demonstrate the performance of the proposed method.
An LSTM model for extracting hierarchical relations between words for better topic modeling
Authors: Javeed Arshad
Published: February 2021

Often when dealing with text data, there exists valuable information that determines the relationship between the words encountered in the corpus. The type of relationship which is sought after is the “has-a” and “is-a” relationship, with which one can build a hierarchical representation of words. Since each language has its own set of rules and syntax, extraction of the relationships ultimately boils down to understanding the syntax of the particular language and using relevant features in the process.

The paper presents a machine-learning model for understanding the language syntax and deducing the relationships between the words encountered. To be specific, a sequence modeling approach if followed, where the model receives a sequence of words and makes use of the various properties of the words to build a hierarchical graph. The algorithm described will be independent of the language, and the model should be versatile enough to be trained for different languages. In addition, the paper also describes how this information can be used to build better topic models, given a corpus of text.
Satellite disturbance detection and rejection with control moment gyros
Authors: Lee Jung-Hyung , Lee Joon-Yong , Oh Hwa-Suk
Published: February 2021

Uncertain external disturbances either secular or oscillating make the satellite attitude be deviated or oscillating from the mission attitude. These disturbances should be detected in short and rejected with proper counter torques of actuators. Nonlinear second order sliding mode observer is one of the good algorithms that can be used for the detection of disturbances’ magnitude and frequencies. With a control law of the integration and dipole rejection filters based on the identified disturbance information, the actuator torques can compensate the disturbances. The spacecraft attitude is then stabilized at the mission attitude within a tolerable error. In this paper, the performances of detection and rejection algorithms are checked respectively in computer simulations. The applicability is proved on a satellite ground simulator recently developed in Korea Aerospace University. The results show that the algorithms work properly with small error, which is due to the low grade of sensors and actuators.
Hierarchical graph attention network for relation extraction
Authors: Sun Hongru , Ni Wancheng , Yang Yiping
Published: February 2021

Previous research on relation extraction has proved the effectiveness of using dependency trees, which build non-local connections between tokens. However, the existing dependency-based models treat the dependency trees as an inherently flat graph, which causes a loss of dependency information for representing sentences. Besides, they fail to consider the fact that the importance of tokens on the dependency tree varies with different relations to be extracted. In this paper, we propose a novel hierarchical graph attention networkHierGAT, which can generate multi-level dependency trees and extract key information from them to improve relation extraction. Specifically, it contains multiple dependency-based graph attention layers, each of which takes a different dependency tree generated by an adaptive subtree pruning strategy as input, and distinguishes the importance of different tokens in a dependency tree. Finally,HierGATintegrates the output token representations of each layer with a multi-head attention mechanism, and learns sentence representation for relation extraction through a pooling layer. The experimental results demonstrate that our method outperforms state-of-the-art baselines on the benchmark datasets.
Extracting a DME area based on graph-based image segmentation and collation of OCT retinal images*
Authors: Shirokanev Alexandr , Ilyasova Nataly , Demin Nikita , Zamyckij Evgeniy
Published: February 2021

This paper proposes a technique for improving the localization of areas of diabetic macular edema. This study is relevant because the incidence of serious eye diseases due to diabetic macular edema is only increasing among the world’s population. The proposed method is graph-based image segmentation. Comparison of optical coherence tomography (OCT) data and retinal images is based on the search and comparison of special points on the original analyzed image and OCT analysis based on these images. Segmentation accuracy is improved by using specially selected parameters. Of these, the optimal parameters obtained in the course of the study made it possible to achieve a segmentation error of 2%.
Discriminative locality-constrained sparse representation for robust face recognition
Authors: Huang Meng , Shao Guifang , Wang Keqi , Liu Tundong , Lu Hao
Published: February 2021

In this paper, a new joint sparse representation method called discriminative locality-constrained sparse representation (DLSR) is proposed for robust face recognition. DLSR incorporates locality and label information of training samples into the framework of sparse representation. Locality information can distinguish dissimilarity between samples and plays an important role in image classification. Compared with the existing methods, DLSR contains more discriminative information of samples and can obtain more discriminative recognition results. Due to the use of l2-norm regularization, DLSR can obtain a closed-form solution. This makes it computationally very efficient. Experimental results based on the benchmark face databases ORL have shown that DLSR can achieve more promising performance than some state-of-the-art methods.
Comparison of Malaria Parasite Image Segmentation Algorithm Using Thresholding and Watershed Method
Authors: Jusman Yessi , Pusparini Anindita , Nazilah Chamim Anna Nur , Kanafiah Siti Nurul Aqmariah Mohd
Published: February 2021

Malaria is an infectious disease caused by plasmodium that lives and breeds in the red blood cells, transmitted by the Anopheles mosquito. During this time, the paramedics to diagnose symptoms use any imagery that is done manually. In the identification analysis of the malaria parasite cell infection, there is a possibility of human error factor done by paramedics because of the number of samples analyzed. This case is because the human eye tends to be tired while working continuously, leading to misclassification and treatment that is not right. Therefore, it takes a computer-based system that facilitates image processing to paramedics or laboratory technicians to identify the parasite cells and reduce human error instances. This research conducted on identification of the thresholding and watershed of segmentation method for three types of plasmodium parasite, namely Plasmodium falciparum, Plasmodium malaria, and Plasmodium vivax. This study offered modifications thresholding and watershed algorithm. The results showed the success of the technique that can effectively segment on the three types of Plasmodium malaria, which has an accuracy rate above 90% as well as the results of the computation time between the thresholding method could segment imagery for 1-2 seconds and the watershed method intelligent segmented representation for 3-4 seconds.
Health impacts of fine particles under climate change mitigation, air quality control, and demographic change in India
Authors: Dimitrova Asya , Marois Guillaume , Kiesewetter Gregor , K C Samir , Rafaj Peter , Tonne Cathryn
Published: February 2021

Despite low per capita emissions, with over a billion population, India is pivotal for climate change mitigation globally, ranking as the third largest emitter of greenhouse gases. We linked a previously published multidimensional population projection with emission projections from an integrated assessment model to quantify the localised (i.e. state-level) health benefits from reduced ambient fine particulate matter in India under global climate change mitigation scenarios in line with the Paris Agreement targets and national scenarios for maximum feasible air quality control. We incorporated assumptions about future demographic, urbanisation and epidemiological trends and accounted for model feedbacks. Our results indicate that compared to a business-as-usual scenario, pursuit of aspirational climate change mitigation targets can avert up to 8.0 million premature deaths and add up to 0.7 years to life expectancy (LE) at birth due to cleaner air by 2050. Combining aggressive climate change mitigation efforts with maximum feasible air quality control can add 1.6 years to LE. Holding demographic change constant, we find that climate change mitigation and air quality control will contribute slightly more to increases in LE in urban areas than in rural areas and in states with lower socio-economic development.
Energetics of critical oscillators in active bacterial baths
Authors: Gopal Ashwin , Roldán Édgar , Ruffo Stefano
Published: February 2021

We investigate the nonequilibrium energetics near a critical point of a non-linear oscillator immersed in an active bacterial bath. At the critical point, we reveal a scaling exponent of the average power exerted by a constant non-conservative torque

⟨

W

̇

⟩

∼

(

D

a

/
τ

)

1
/
4

, where D
a is the effective diffusivity and τ the correlation time of the bacterial bath described by a Gaussian colored noise. Other features that we investigate are the average stationary power and the variance of the work both below and above the saddle-node bifurcation. Above the bifurcation, the average power attains an optimal, minimum value for finite τ that is below its zero-temperature limit. Furthermore, we reveal a finite-time uncertainty relation for active matter which leads to values of the Fano factor of the work that can be below 2k
B
T
eff, with T
eff the effective temperature of the oscillator in the bacterial bath. We analyze different Markovian approximations to describe the nonequilibrium stationary state of the system. Finally, we illustrate our results in the experimental context by considering the example of driven colloidal particles in periodic optical potentials within an E. Coli bacterial bath.
Rapid detection of SARS-CoV-2 infection by multicapillary column coupled ion mobility spectrometry (MCC-IMS) of breath. A proof of concept study
Authors: Steppert Claus , Steppert Isabel , Sterlacci William , Bollinger Thomas
Published: February 2021

There is an urgent need for screening of patients with a communicable viral disease to cut infection chains. Recently, we demonstrated that ion mobility spectrometry coupled with a multicapillary column (MCC-IMS) is able to identify influenza-A infections in patients’ breath. With a decreasing influenza epidemic and upcoming SARS-CoV-2 infections we proceeded further and analyzed patients with suspected SARS-CoV-2 infections. In this study, the nasal breath of 75 patients (34 male, 41 female, aged 64.4 ± 15.4 years) was investigated by MCC-IMS for viral infections. Fourteen were positively diagnosed with influenza-A infection and sixteen with SARS-CoV-2 by reverse transcription polymerase chain reaction (RT-PCR) of nasopharyngeal swabs. In one patient RT-PCR was highly suspicious of SARS-CoV-2 but initially inconclusive. The remaining 44 patients served as controls. Breath fingerprints for specific infections were assessed by a combination of cluster analysis and multivariate statistics. There were no significant differences in gender or age according to the groups. In the cross validation of the discriminant analysis 72 of the 74 clearly defined patients could be correctly classified to the respective group. Even the inconclusive patient could be mapped to the SARS-CoV-2 group by applying the discrimination functions. Conclusion: SARS-CoV-2 infection and influenza-A infection can be detected with the help of MCC-IMS in breath in this pilot study. As this method provides a fast non-invasive diagnosis it should be further developed in a larger cohort for screening of communicable viral diseases. A validation study is ongoing during the second wave of COVID-19.

Trial registration: ClinicalTrial.gov, NCT04282135 Registered 20 February 2020—Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT04282135?term=IMS&draw=2&rank=1
Impacts of Drivers’ Physiological and Psychological Characteristics on Road Traffic Safety Based on Traffic Safety Management Database
Authors: Cheng Hui-ting
Published: February 2021

As traffic accidents dramatically increased on highways, this paper aims to study how drivers’ physiological and psychological characteristics can affect traffic safety. This paper studies and analyses the physiological and psychological characteristics of drivers during highway congestions, including drivers’ eye blink rate, level of fatigue and heart rate. Moreover, the k-means clustering algorithm is used to determine the relationship between the drivers’ level of fatigue and dangerous driving paths. It is found that the drivers’ average blink rate under traffic congestion is higher than those under normal conditions, which indicates that traffic congestion can affect the driver’s visual state; The longer traffic congestion lasts, the higher level of fatigue the drivers have, and the more dangerous driving paths appear. This paper can provide a theoretical basis for the studies of how to reduce unsafe driving behavior resulting from drivers’ dangerous driving convictions.
Optimization of Palletized Unit Implants Dispatch Considering Less than Truckload Transportation in Auto Parts Industry
Authors: Feng Shupei , Song Rui , Xue Shouqiang
Published: February 2021

In recent years, the acceleration of economic globalization has played an irreplaceable role in promoting the development of modern logistics industry. Reducing production and operating costs, reducing logistics costs, and increasing enterprise competitiveness have become new challenges of the rapid development for the logistics industry. At the same time, the demand for automobiles has also increased significantly which has strongly driven the development of auto parts industry. A method to optimize palletized unit implants dispatch in auto parts industry which adopts less than truckload (LTL) transportation is proposed in this paper. An optimization model of palletized unit implants dispatch is constructed with the goal to minimize the total transportation cost and the constraints including dispatching demand, dispatching time and so on. And the effectiveness of the model and algorithm is verified by case study. The results show that the dispatch optimization model of shared palletized unit implants considering less than truckload transportation is 7.5% less than full dispatch mode and 146.6% less than full lease mode.
Optimization of Opening Scheme of ETC/MTC Toll Lane Based on Cost and Benefit Analysis
Authors: Zhang Hao , Cheng Cheng , Zhang Changjian , He Jie , Xu Yang , Chen Yikai , Hong Qiong
Published: February 2021

In recent years, with the popularization of electronic toll collection systems (ETC), expressway toll stations in China have developed into a mixed toll form jointly deployed by ETC toll lanes and MTC toll lanes, presenting a development trend based on ETC toll lanes. Since the toll collection system has the important function of “credit repayment“, the relationship between operation benefit and cost will become an important indicator for measuring the toll station system. Taking the minimum cost and the maximum benefit of the toll station under normal operating condition as the optimization goals, a multi-objective nonlinear optimization model is established within the seek for balance between cost and benefit, so as to obtain an open plan with better toll lanes. The Nanjing-Hangzhou toll station is used as an example to verify the model. Furthermore, based on the trend of the future traffic flow and the increase in the proportion of ETC vehicles, the distribution law of the optimal opening schemes of the toll lane under different traffic volumes and different traffic flow structures is analyzed, which provides experience support for the construction and operation of toll stations in the future.
Study on the Law of Drivers’ eye Movement Index in Different Landscape Environment
Authors: Shang Yan , Zhu Shoulin , Qi Chunhua
Published: February 2021

To study the law of drivers’ eye movement indices,indoor simulation driving experiment method was adopted, two-lane second-class grassland highway was designed to simulate real road conditions. 48 subjects were selected for the experiment,groups were divided according to different driving ages, three eye movement sensitive indexes including fixation duration, pupil diameter and scan range were extracted, the variation rule of eye movement index of drivers with different experience under different landscape environment was quantified. It was found that the relationship between the landscape environments and eye movement index was U-shaped,the changes of eye movement indexes of drivers at different driving ages were different.The results showed that 4/km was the optimal threshold number of combined elements.In this environment, the change rate of driver eye movement index was the largest,extraction information was the most;When the number of elements was greater than or less than 4/km, the change rate of driver eye movement index would decrease. The results could provide reference for improving and optimizing the design of grassland highway landscape environment.
Development and Application of 3D Visualization Platform for Flood Evolution in Le’an River Basin of Wuyuan
Authors: Yang Bin , Ma Jianming , Huang Guoxin , Cao Daling
Published: February 2021

With the rapid development of computer network technology, virtual display technology has become a typical representative of modern information technology, which can provide more efficient and intuitive technical means for flood prevention and risk assessment of water conservancy departments, and make more innovations and breakthroughs in the field of 3D simulation. This paper takes the area of Wuyuan County in the upper reaches of Le’an River in Poyang Lake as an example. Based on WebGIS technology, spatial database technology, CTS virtual display technology and combined with TOPMODEL semi-distributed hydrological model and IFMS domestic flood analysis software, it uses computer languages such as C#.NET and Java to carry out secondary development, explore and build a three-dimensional immersive hydrological multi-element virtual reality platform with real-time interactive display function, and realize the dynamics simulation display of three-dimensional data query, water and rain monitoring, flood evolution, submergence analysis, disaster assessment and other scenes under the three-dimensional perspective. It also provides an auxiliary decision-making platform for flood control and disaster reduction in the river basin, and further improves the guarantee level of water safety in the river basin.
Investigation and Research on Geological Disasters in Nanzheng County
Authors: Yao Zhang , Shunli Han , Shaoqiang Guo , liangliang Bai
Published: February 2021

Based on the data from the detailed survey of geological disasters in Nanzheng County, Shaanxi Province, the natural situation of Nanzheng County was introduced. The types, status and development rules of geological disasters in Nanzheng County were evaluated, and the formation conditions and influencing factors of its geological disasters were systematically analyzed and researched, which provided a geological basis for the prevention and control of geological disasters.
Research on Influencing Factors of Reasonable Distance of Shallow Buried Close Tunnel in Weak Surrounding Rock
Authors: Zaifeng Yao , Jiantao Guo , Yishuo Liu , Wenyuan Gao
Published: February 2021

In order to study the influence of different spans, depths, heights and initial stresses on the reasonable clearance of shallow tunnels in weak surrounding rock. This article uses numerical simulation technology. The judging standard is whether the plastic zone of the middle rock pillar is through. The factors affecting the reasonable clear distance of the small clear tunnel are analysed. The results show that the reasonable clear distance of small-distance tunnels under shallow buried conditions gradually increases as the tunnel depth increases. The reasonable clearance distance of the tunnel increases as the lateral pressure coefficient of the surrounding rock decreases. For small-distance tunnels with the same buried depth and same span, the reasonable clearance increases as the tunnel height increases.
Quantitative Research Based on Parametric Simulation of Waterlogging on Bridge Deck
Authors: Cai Wenhao , Huang Ling
Published: February 2021

With the rise of the bridge construction wave, the problem of waterlogging on bridge deck (WBD) also followed. The problems of WBD will cause serious economic losses, restrict the benign development of urban traffic and reduce the life quality of residents. The computational fluid dynamics (CFD) method is adopted to quantitatively research the WBD problem due to its high efficiency, low-cost and outstanding performance of visualization. In addition, four factors including rainfall, performance of the grates, mode of alignment change and disease characteristics have been parameterized simulated. In view of the influence of different factors on the WBD problem, corresponding suggestions in daily operation and management have been put forward in the present paper.
Research on the Selection and Optimization of Horizontal Swirling Energy Dissipation Flood Discharge Tunnel
Authors: Zhang Ying , Di Shengjie , Zhou Heng
Published: February 2021

Through the study of the diameter control of the horizontal swirling efficiency shaft and the swirling tunnel and the cross-section of the aeration sill, a flood discharge tunnel with a scale of about 100 meters and a discharge volume of more than a thousand is obtained. The horizontal swirling energy dissipation type is combined with the diversion tunnel. At the time, the diameter of the shaft can be controlled and determined according to the average velocity of 15-20m/s; the diameter of the swirling hole can be calculated according to the empirical formula D=(Q2/g)0.2. In order to reduce the impact of water flow pulsation on the concrete lining and surrounding rock of the shaft, the flood discharge tunnel inlet should adopt a submerged flow pattern. Its discharge capacity will be controlled by the cross section (A) of the aeration sill in the shaft and the inlet section (σ) of the swirl chamber. When the slope of the aeration sill is 1:2.5 to 1:3.0, σ/A should be controlled at 1.05. The research results can provide a reliable basis for the design of horizontal swirling energy dissipation.
Correlation analysis method of track irregularity indexes
Authors: Li Shiyi
Published: February 2021

Research on the correlation analysis method of track irregularity indexes has an important guiding role in selecting targeted maintenance decision-making indexes and guiding maintenance decision making related to track irregularity state. In this study, the track irregularity index structures and track quality index were used to design the correlation analysis method of track irregularity indexes. To verify the effectiveness of this method, a total of 48 track inspection car historical data from September 2014 to February 2017 and November 2017 to December 2018 of the Shenmu-Shuozhou railway Hexi transportation division was used as the case study. The results show that the correlation analysis method proposed in this study can be used to effectively analyze the correlation between the track irregularity indexes. This is verified by comparing with the correlation analysis method based on the standard deviations of track irregularity indexes.
Seismic response analysis of high-pier long-span continuous rigid-frame bridges under far-field long-period ground motions
Authors: Yanan Wang , Guangwu Tang , Haiming Liu , Yonghui Liu , Bin Peng
Published: February 2021

The seismic response of a high-pier long-span continuous rigid frame bridge under the action of far-field long-period ground motions is studied. A numerical calculation model of a high-pier long-span continuous rigid frame bridge whose span layout is (95+170+95)m is established by using finite element software. According to the established wave selection criteria, 10 long-period far-field seismic records and 10 ordinary seismic records are selected from the strong earthquake record database. Using the dynamic time history analysis method, the seismic response of the bridge structure under the far-field long-period seismic record and the ordinary seismic record was obtained through calculation, and a comparative analysis was carried out. The results show that the seismic response of a high-pier long-span continuous rigid frame bridge under far-field long-period ground motions is significantly greater than that of ordinary ground motions, the effect of ground motion spectrum characteristics should be considered in seismic design of such Bridges.
Numerical simulation of the influence of ground fissures on the deformation characteristics of the surface
Authors: Tian Yingjie , Xu Zhipeng , Hu Hongwei
Published: February 2021

in order to study the influence of ground fissures on the construction of expressway, a ground fissure (F1) with a strike of NE20∼45° and length of 120km in Yunnan Province is selected as the research object. The FLAC3D numerical software is used to study the characteristics of displacement and stress. The results show that: (1) under normal fault activity, vertical displacement mainly develops hanging wall. (2) The overall variation law of the surface subsidence curve presents an “s“ type distribution. (3) The stress of the two plates changes with the fracture activity, which is manifested in the stress increasing area in the footwall and the stress decreasing area in the hanging wall.
Research on Integrated Liquefaction Assessment for Stone Column Applied in Coral Sand Area within High Earthquake Magnitude Zone
Authors: Liang Xiaocong , Chen Pingshan , Qiu Qingchang , Wang Jing , Zhu Mingxing
Published: February 2021

For deep and thick coral reef sand with high fine contents in high magnitude zone where the traditional vibro-compaction is not sufficient to compact, the stone column shall be applied as liquefaction mitigation measurement. Based on the analysis of the three major anti liquefaction criterion of stone column, an integrated evaluation method combined densification, shear stress distribution and drainage criterion for liquefaction mitigation was proposed, further a field test with 10.1% replacement ratio was launched. According to the analysis of the test result, the loose reclamation coral sand could be improved to an average 4.3 times SPT N value comparing. While for the medium dense coral sand, the densification among columns is limited, SPT N value is only increased by 1.3 times, and the densification decreases with fines content increasing. Further, the safety factor of liquefaction is only 0.70 and 1.01 when only considering densification criterion, or combined with shear stress redistribution criterion. However, if assessed by integrated assessment method which is mainly based on drainage criterion together with densification criterion and shear stress redistribution criterion, the calculated pore pressure ratio is still far less than the design value of 0.6 and that indicated the risk of liquefaction is still low. Moreover, when the bottom feed vibro-replacement process is adopted, the permeability coefficient of stone gravel is expected to reduce by half after stone column construction completion.
Research on Cavitation Characteristics and Control Measures of Horizontal Swirl Spillway Tunnel
Authors: Huang Peng , Zhou Heng , Di Shengjie , Lu Xi
Published: February 2021

The swirling chamber of the horizontal swirling energy dissipation is the key part to form the swirling flow, but the swirling chamber and the rising sill are also sensitive parts of cavitation. In order to improve its anti-cavitation performance, the side wall aeration and pressure should be increased. This paper proposes to set up an annular aeration sill in the middle and upper part of the shaft, and use a vent pipe to supplement the air under the sill to increase the aeration volume of the swirling chamber and the ascending sill. Both the monitoring data and the flow surface inspection show that the noise of the cavitation water flow in the swirling chamber of the horizontal swirling tunnel is weak. There are no obvious signs of negative pressure and cavitation. The ventilation facilities of the shaft section are effective, and the water flow is fully air-entrained. The water flow aeration can effectively protect the surface of the flow channel. This measure can effectively solve the anti-cavitation problem.
Response analysis of inertia mass under dynamic load
Authors: Tian Zhen , Liang Yanfang , Zhao Yongxi , He Jiangtao , Zhai Minghui , Luo Ye , Luo Yuxiang , Sun Jianyun , Yang Shaolin , Geng Dongqing
Published: February 2021

In the fields of civil engineering, aerospace and mechanical manufacturing, inertia mass is a very common form of load. The research on the response of inertia mass under dynamic load can provide a strong basis for the research in the above fields. In this paper, in order to study the response of inertia mass under dynamic load, a high-speed dynamic actuator is used to carry out sinusoidal loading and impact loading on an inertia mass, and its response under dynamic load is studied, which can provide a basic basis for the follow-up study of inertia mass. It can be concluded from the response analysis of inertia mass that the motion of inertia mass satisfies the basic laws of kinematics and dynamics.