bluuebunny/crossref_metadata_2025 huggingface dataset:
Cross structured two-dimensional violet phosphorene with extremely high deformation resistance
Authors: Zhang Bo , Zhang Lihui , Wang Zhenyu , Li Yongfei , Cheng Yonghong , Ma Lifeng , Zhang Jinying
Published: May 2021

Cross structures have been well adopted as load bearing structures due to their excellent mechanical properties.
Engineering of stealth (maghemite/PLGA)/chitosan (core/shell)/shell nanocomposites with potential applications for combined MRI and hyperthermia against cancer
Authors: Fernández-Álvarez Fátima , Caro Carlos , García-García Gracia , García-Martín María Luisa , Arias José L.
Published: May 2021

Biocompatible and long-circulating (maghemite/poly(d,l-lactide-co-glycolide))/chitosan (core/shell)/shell nanoparticles with promising theranostic applications (biomedical imaging and hyperthermia) against cancer.
Word Recognition and Word Prediction in Preschoolers With (a Suspicion of) a Developmental Language Disorder: Evidence From Eye Tracking
Authors: van Alphen Petra , Brouwer Susanne , Davids Nina , Dijkstra Emma , Fikkert Paula
Published: May 2021

Purpose

This study compares online word recognition and prediction in preschoolers with (a suspicion of) a developmental language disorder (DLD) and typically developing (TD) controls. Furthermore, it investigates correlations between these measures and the link between online and off-line language scores in the DLD group.

Method

Using the visual world paradigm, Dutch children ages 3;6 (years;months) with (a suspicion of) DLD (n= 51) and TD peers (n= 31) listened to utterances such as, “Kijk, een hoed!” (Look, a hat!) in a word recognition task, and sentences such as, “Hé, hij leest gewoon een boek” (literal translation:Hey, he reads just a book) in a word prediction task, while watching a target and distractor picture.

Results

Both groups demonstrated a significantword recognitioneffect that looked similar directly after target onset. However, the DLD group looked longer at the target than the TD group and shifted slower from the distractor to target pictures. Within the DLD group, word recognition was linked to off-line expressive language scores. Forword prediction,the DLD group showed a smaller effect and slower shifts from verb onset compared to the TD group. Interestingly, within the DLD group, prediction behavior varied considerably, and was linked to receptive and expressive language scores. Finally, slower shifts in word recognition were related to smaller prediction effects.

Conclusions

While the groups' word recognition abilities looked similar, and only differed in processing speed and dwell time, the DLD group showed atypical verb-based prediction behavior. This may be due to limitations in their processing capacity and/or their linguistic knowledge, in particular of verb argument structure.
Does the Speech Cue Profile Affect Response to Amplitude Envelope Distortion?
Authors: Souza Pamela E. , Ellis Gregory , Marks Kendra , Wright Richard , Gallun Frederick
Published: May 2021

Purpose

A broad area of interest to our group is to understand the consequences of the “cue profile” (a measure of how well a listener can utilize audible temporal and/or spectral cues for listening scenarios in which a subset of cues is distorted. The study goal was to determine if listeners whose cue profile indicated that they primarily used temporal cues for recognition would respond differently to speech-envelope distortion than listeners who utilized both spectral and temporal cues.

Method

Twenty-five adults with sensorineural hearing loss participated in the study. The listener's cue profile was measured by analyzing identification patterns for a set of synthetic syllables in which envelope rise time and formant transitions were varied. A linear discriminant analysis quantified the relative contributions of spectral and temporal cues to identification patterns. Low-context sentences in noise were processed with time compression, wide-dynamic range compression, or a combination of time compression and wide-dynamic range compression to create a range of speech-envelope distortions. An acoustic metric, a modified version of the Spectral Correlation Index, was calculated to quantify envelope distortion.

Results

A binomial generalized linear mixed-effects model indicated that envelope distortion, the cue profile, the interaction between envelope distortion and the cue profile, and the pure-tone average were significant predictors of sentence recognition.

Conclusions

The listeners with good perception of spectro-temporal contrasts were more resilient to the detrimental effects of envelope compression than listeners who used temporal cues to a greater extent. The cue profile may provide information about individual listening that can direct choice of hearing aid parameters, especially those parameters that affect the speech envelope.
Design and research of a robotic system for ultrasonic‐assisted lamellar keratoplasty
Authors: Xiao Jingjing , Li Mengqiong , Wang Chiming , Pi Jun , He Hui
Published: May 2021

In order to solve the problem of uncontrollable cutting depth and the rough incision edge of the cornea with manual trephine in lamellar keratoplasty, an ultrasonic‐assisted corneal trephination method has been proposed for the first time in accordance with the advantage of ultrasonic vibration cutting, and the corresponding robotic system has been designed and researched. According to the traditional process of lamellar keratoplasty, the requirements of the surgical robotic system were first proposed. On this basis, the robotic system was designed and its schematic diagram was introduced. Second, the key components of the robotic body such as the eccentric adjusting mechanism and the end‐effector of ultrasonic scalpel were illustrated, which can realise corneal trephination of different incision diameters without scalpel replacement. Then the operation flow chart of a robot‐assisted lamellar keratoplasty was put forward. Finally, the preliminary verified experiments were performed using a grape and a porcine eyeball, respectively, in vitro with the prototype system. The results show that the robotic system can basically satisfy the operation requirements of lamellar keratoplasty. Owing to the less cutting force and smoother corneal incision edge of ultrasonic‐assisted lamellar keratoplasty compared with manual trephine, it was proved to be more feasible and superior.
Prediction of instantaneous likeability of advertisements using deep learning
Authors: Saha Dipayan , Rahman S.M.Mahbubur , Islam Mohammad Tariqul , Ahmad M. Omair , Swamy M.N.S.
Published: May 2021

The degree to which advertisements are successful is of prime concern for vendors in highly competitive global markets. Given the astounding growth of multimedia content on the internet, online marketing has become another form of advertising. Researchers consider advertisement likeability a major predictor of effective market penetration. An algorithm is presented to predict how much an advertisement clip will be liked with the aid of an end‐to‐end audiovisual feature extraction process using cognitive computing technology. Specifically, the usefulness of different spatial and time‐domain deep‐learning architectures such as convolutional neural and long short‐term memory networks is investigated to predict the frame‐by‐frame instantaneous and root mean square likeability of advertisement clips. A data set named the ‘BUET Advertisement Likeness Data Set’, containing annotations of frame‐wise likeability scores for various categories of advertisements, is also introduced. Experiments with the developed database show that the proposed algorithm performs better than existing methods in terms of commonly used performance indices at the expense of slightly increased computational complexity.
Accurate and efficient solution of electromagnetic scattering from randomly rough surface using MoM‐SMCG with adaptive quadrature
Authors: Du Yanlei , Yin Junjun , Li Xiang , Gao Fan , Yang Jian
Published: May 2021

An adaptive quadrature method is proposed and implemented with the full‐wave MoM‐SMCG to accurately and efficiently solve the electromagnetic scattering from randomly rough surfaces. Without using high‐order basis functions and dense surface discretisation, high numerical accuracy of computing the inner integrals for near‐field impedance matrix elements is ensured by exploiting the orthogonal Legendre polynomials. Far‐field interactions are calculated using the acceleration algorithms and the iterative solver to archive reasonable computational complexity and memory consumption. The proposed method is validated on solving the electromagnetic scattering and emission from rough ocean surfaces with fine‐scale roughness and large dielectric constants. By comparing to the existing methods, simulation results indicate the proposed method has high computational efficiency and memory saving with also maintaining good accuracy.
Sampling criteria for mutual over‐the‐air synchronisation of radar sensors
Authors: Dallmann Thomas
Published: May 2021

Synchronisation of radar systems can be used to suppress interference and enable communication between radars. In this paper, a generalised Kuramoto model is proposed, which can be used to synchronise pulse repetition frequencies of two radars over‐the‐air. The generalised approach allows the adjustment of a sampling factor which influences the convergence of the two pulse repetition frequencies. Furthermore, sampling criteria are derived, which can be used to estimate whether convergence occurs. Finally, it is shown by means of simulation that the model together with the criteria allows to reliably predict convergence and to perform synchronisation.
Lightning protection of multi‐fracture arc‐quenching lightning protection gap for 35 kV distribution lines
Authors: Wu Dong , Wang Ju‐feng
Published: May 2021

Owing to the low insulation level of 35 kV distribution lines, lightning outage accidents and huge economic losses occur frequently. Therefore, a multi‐fracture arc‐quenching lightning protection gap (MFALPG) for 35 kV distribution lines is developed to ensure the safety and stability of power supply. Here, the principle of MFALPG is presented through the electromagnetic self‐contraction effect and qualitative modelling theory. In order to investigate the coupling effect between high‐energy compressional waves and arcs, a mathematical model of airflow coupled arc was developed to simulate and analyse the arc‐quenching process. Theoretical analysis and simulation results show that the high‐energy compressional wave is triggered by the impulse arc rapidly, and the arc conductivity drops abruptly in a short time. Finally, a lightning impulse discharge test and the power frequency withstand voltage test are performed to determine the 35 kV power frequency continuous current interruption test parameters. Under the action of the MFAPLG, the entire time of arc duration is less than 3 ms, and reignition phenomenon of the arc is not found after the subsequent power frequency voltage is restored.
Vision‐based vehicle speed estimation: A survey
Authors: Fernández Llorca David , Hernández Martínez Antonio , García Daza Iván
Published: May 2021

The need to accurately estimate the speed of road vehicles is becoming increasingly important for at least two main reasons. First, the number of speed cameras installed worldwide has been growing in recent years, as the introduction and enforcement of appropriate speed limits are considered one of the most effective means to increase the road safety. Second, traffic monitoring and forecasting in road networks plays a fundamental role to enhance traffic, emissions and energy consumption in smart cities, being the speed of the vehicles one of the most relevant parameters of the traffic state. Among the technologies available for the accurate detection of vehicle speed, the use of vision‐based systems brings great challenges to be solved, but also great potential advantages, such as the drastic reduction of costs due to the absence of expensive range sensors, and the possibility of identifying vehicles accurately. This paper provides a review of vision‐based vehicle speed estimation. The terminology and the application domains are described and a complete taxonomy of a large selection of works that categorizes all stages involved is proposed. An overview of performance evaluation metrics and available datasets is provided. Finally, current limitations and future directions are discussed.
Removing broadside null of symmetric long‐slot antennas by using a coating layer
Authors: Shahrbandian Mohaddeseh , Aliakbarian Hadi
Published: May 2021

This study presents a new concept in the design of symmetric long‐slot leaky‐wave antennas. Theoretically, a radiation null in the broadside direction of these antennas exists. The main idea of this study is to use a cover or coating layer to convert this null to a peak in the radiation pattern. The presence of the coating on the slot not only changes the leaked mode of the waveguide but also rotates its polarisation by 90°. As a proof of concept, a relatively small long‐slot LWA is designed and fabricated on a C‐band WR‐159 waveguide, which is covered by an FR4 layer. The simulated relative broadside gain of the antenna with the coating over the antenna without the coating tends to infinity because of the presence of the null. Our simple measured results of the radiation pattern confirm the theory with more than 18 dB improvement. The realised gain of the antenna with a coating layer at broadside is 11.1 dBi with 9.8° half‐power beam‐width.
IoT focused VHF and UHF propagation study and comparisons
Authors: Wright D.P. , Ball E.A
Published: May 2021

As the market for internet of things (IoT) is growing and due to Ofcom's decision to reassign parts of the very high frequency (VHF) spectrum in the UK for IoT use, a propagation study has been conducted using the newly released VHF spectrum and the currently commercially operated ultra‐high frequency (UHF) spectrum, in order to compare and contrast the suitability of the VHF spectrum for IoT use. The authors conducted their study in a number of different environments (rural, suburban, urban and dense urban), with measurement equipment deployed in a manner suitable for a portable IoT use case. Results are presented in comparison to other propagation studies available in the literature and widely used propagation models such as the Hata model. Shadowing and noise are also measured and examined. It is found that current propagation models do not provide adequate predictions within the considered use case, but found it is possible to calculate log‐distance based models that provide good predictions. Path‐loss is found to be constantly lower at VHF than UHF, but radio frequency noise is consistently higher. The newly released spectrum is found to be suitable for IoT deployments in all the examined environments.
Experimental and simulation studies of radiation‐induced single event burnout in SiC‐based power MOSFETs
Authors: Peng Chao , Lei Zhifeng , Chen Ziwen , Yue Shaozhong , Zhang Zhangang , He Yujuan , Huang Yun
Published: May 2021

The single event burnout (SEB) effects of SiC power MOSFET are investigated by irradiations. An SEB is observed when drain biased above 400 V for 181Ta ion irradiation. The failure analysis shows a melting “hole” near the gate region due to the thermal runaway. Based on TCAD simulations, the impact ionization and parasitic bipolar are the key factors to trigger SEB in SiC MOSFET. Unlike the impact ionization, the turning on of the parasitic bipolar is not necessary for an SEB. But it will significantly reduce the threshold of SEB. Except for SEB, another permanent damage mode is also observed, which is manifested as the increase of leakage current and the abnormal of the output characteristics. This damage may be related to the latent track produced by heavy ion according to the failure analysis. The SEBs are observed for proton irradiations. The maximum LET value of the proton‐induced secondary ions can reach 13.9 MeV cm2/mg for 100 MeV proton. The simulations imply that most of the secondary ions can contribute to SEB. The biggest discrepancy from heavy ion irradiation is that no leakage current increases and output characteristics degradations are observed for the device without SEB after proton irradiation.
Research on Bus Voltage of DC Microgrid Containing Hybrid Energy Storage System
Authors: Feng Feiyue , Chi Changchun
Published: May 2021

In order to suppress the busbar voltage fluctuations in the DC microgrid, this paper establishes an optical storage DC microgrid system with a hybrid energy storage system to achieve the purpose of stabilizing the DC bus voltage. This system focuses on the component hybrid energy storage unit, and uses the structure of three batteries and supercapacitors (SC) in parallel to improve the stability of the system, while ensuring the frequency division distribution between devices.
Research on Defect Recognition of Lithium Battery Pole Piece Based on Deep Learning
Authors: Li Jiwei , Li Linsheng , Xu Changlu
Published: May 2021

In the field of defect recognition, deep learning technology has the advantages of strong generalization and high accuracy compared with mainstream machine learning technology. This paper proposes a deep learning network model, which first processes the self-made 3, 600 data sets, and then sends them to the built convolutional neural network model for training. The final result can effectively identify the three defects of lithium battery pole pieces. The accuracy rate is 92%. Compared with the structure of the AlexNet model, the model proposed in this paper has higher accuracy.
Research and Development of a Digital Safety Monitoring Device for Attached Lifting Scaffolding
Authors: Zhang Qiang
Published: May 2021

This paper introduces a digital safety monitoring device for attached lifting scaffold, including attached lifting scaffold and safety monitoring control device. The safety monitoring device includes monitoring point, intermediate station, control center, communication converter, display and mobile terminal. The monitoring point is set on the attached lifting scaffold, the monitoring point is wirelessly connected with the intermediate station. The intermediate station transmits data to the control center through network mapping. The control center is respectively connected with the display and the communication converter, and the communication converter is connected with the mobile terminal. The utility model has simple structure, convenient operation, can intuitively monitor various values of the monitoring points, and provides a strong guarantee for the construction safety of the attached lifting scaffold.
Research on the influence of uneven solar radiation distribution on the radiant floor heating system in railway stations on Tibetan Plateau
Authors: Zheng Jiacheng , Yu Tao , Lei Bo , Lv Ruixin , Chen Chen , Luo Xiujing
Published: May 2021

In cold regions, radiant floor heating systems are commonly used in public buildings due to better thermal comfort and lower energy consumption. However, in transportation buildings with many transparent envelopes such as railway stations on Tibetan Plateau, the strong solar radiation entering into the station may cause local overheating, which has a great effect on the radiant floor heating system. In this paper, a railway station on Tibetan Plateau is simulated to investigate the influence of uneven solar radiation distribution on the radiant floor heating system. Results show that due to the strong solar radiation, the floor surface temperature and indoor operative temperature in some parts of the waiting hall can reach up to 30 °C and 26 °C, respectively. The temperature difference of the floor surface can even exceed 5 °C occasionally during the heating period. According to the results, it can be found that the method of reducing the heating in the area with strong solar radiation and making full use of solar radiation for heating is an effective way to improve the indoor thermal comfort and reduce the heating energy consumption of heating system.
Experimental Studies on the Structural Strength of Pumping Concrete in Winter
Authors: Chang Sheng , Qunmei Zhou , Shangzhuan Ling
Published: May 2021

The strength growth of concrete depends on the hydration reaction of cement. Curing temperature and humidity are important conditions to determine the hydration rate of cement. In this paper, rebound method is used to detect the structural strength of pumping commercial concrete in winter construction in Jinhua. The relationship between temperature, rebound value and compressive strength value is analyzed based on the concrete strength detection data. At the same time, some effective measures are put forward to solve the problems in winter construction.
Research on Liquid CO2 Phase Transition Ejection Technology
Authors: He Danna , Zuo Youxing , Shen Bailiang , Shi Qingsan , Wang Heng
Published: May 2021

Due to the low temperature and clean gas, liquid CO2 phase transition ejection technology has outstanding advantages such as high versatility, low launch cost, and environmental friendliness, which will open up a new research field for the development of missile launch technology. Through the study of phase transition characteristics of liquid CO2 in this paper, a mathematical model of internal ballistics of the liquid CO2 phase transition ejection power system is established. And through simulation calculation, the launching parameters such as the pressure in the launcher, the velocity and acceleration of the missile are obtained, and they is compared with the experiment data to verify the validity of the model.
Civil Aircraft metal structure superfluous hole repair and stress evaluation method
Authors: Zhu Weibin , Wang Kai , Sun Xiaodong , Yu Xue , Diao Jixiang
Published: May 2021

Civil aircraft is the most complicated production of the world and during the manufacture various kinds of manufacture nonconformities occur at times. Superfluous hole is one of the most typical nonconformity types. When coping with this kind of problem, engineers often lack experience or standard treatment criteria, which may cause verbose treatment progress, low production efficiency or even technique risk. This article firstly introduces reasons for different types of superfluous holes and figures out treatment procedure and methods and analyses strength evaluation and assessment method.
Microwave-assisted pyrolysis of seaweed biomass for aromatics-containing bio-oil production
Authors: Wang Xinyun , Li Chuan , Chen Mingqiang , Wang Jun
Published: May 2021

Microwave-assisted pyrolysis of seaweed biomass was conducted using a microwave pyrolysis system. The product yields were determined and the components of bio-oil were analyzed by a gas chromatography-mass spectrometry (GC-MS). Results showed that as the pyrolysis temperature increased from 400 °C to 600 °C, the gas yield increased and the bio-char yield decreased. However, the bio-oil yield rose firstly and then reduced. The maximal bio-oil yield was 18.4 wt.% when pyrolysis temperature was 500 °C. The bio-oil obtained is a mixture of very complex organic compounds, mainly consisting of aldehydes, ketones, alcohols, esters, phenols, aliphatic hydrocarbons, aromatic hydrocarbons and nitrogencontaining compounds. The relative content of aromatics in bio-oil accounted for about 16%. The above results reveal that microwave-assisted pyrolysis of seaweed biomass is a feasible method to produce aromatics-containing bio-oil.
Research on Thermal Reflection and Cooling Curing Coating Material of Nano Modified Emulsified Asphalt for Urban Road Pavement
Authors: Zhong Yongqiang
Published: May 2021

Based on the development of thermal reflective coating materials at home and abroad, modified emulsified asphalt was selected as the substrate material and nano TiO2 was selected as the filler. Different filler dosage was selected, the optimal ratio of thermal reflective coating was obtained by analyzing the pavement temperature data measured in the field experiment. Finally, the construction technology of pavement thermal reflection coating material is described in detail.
Recovery of Copper and Cyanide from Copper-cyanide Solution by Direct Electrolysis
Authors: Gao Teng-Yue , Xu Chao , Qin Guang-Lin
Published: May 2021

Using direct electrolysis method, the recovery of copper and cyanide from high concentration copper cyanide solution was researched. The distribution of copper cyanide species was calculated by stability constants and balance equation. The results showed that the cupric ion was confirmed to generate at low potential (<0.4V) on the titanium electrode coated with iridium and tantalum oxides during the electrolysis process, which led to the oxidation of cyanide and the precipitate obtained on the anode was proved to be cupric hydroxide by XRD at high potential. The copper was recovered by direct electrowinning, the recovery of copper increased with increasing temperature, which reached 80% at 70°C; but the loss of cyanide was serious, the free cyanide concentration was significantly lower than original value.
Study on the Performance of the Physical Foaming Warm-mix Recycled Asphalt Mixture
Authors: Zhigang Zheng , Yunwu He , Tao Wang , Hanxin Wei , Xiayi Liang , Xin Xiao , Tao Liu
Published: May 2021

In order to evaluate the performance of the physical foaming warm-mix recycled asphalt mixture (WRAM), the hot mix plant recycling technology was adopted to develop AC-20 hot-mix recycled asphalt mixture (HRAM) and the WRAM of different reclaimed asphalt pavement (RAP) contents. The high temperature stability, water stability and low temperature crack resistance performance of the reclaimed asphalt pavement were evaluated. The results indicate that the physical foaming WRAM feature better high temperature stability, water stability and low temperature crack resistance compared to those of HRAM. With the increase in RAP contents, the high temperature stability of the physical foaming WRAM and HRAM rises notably but the water stability and low temperature crack resistance performance continues to drop.
Analysis of Lithium-ion Battery Micro-overcharge Cycle Damage Mechanism Based on Electrochemical Impedance Spectroscopy
Authors: Zhou Jingjing , Chao Peipei , Zhang Nutao , Wang Peng , Cheng Duanqian , Zeng Ganghui , Huang Peifeng
Published: May 2021

Electrochemical impedance spectroscopy (EIS) was used to study the micro-overcharge cycle damage mechanism of Lithium-ion batteries (LIBs). Micro-overcharge cycle experiments of LIBs were carried out, and the capacity fading of LIBs under different charging cut-off voltages were analyzed. It was found that the capacity fading rate of LIBs increased with the rising of overcharge cut-off voltages and the increasing of cycle numbers. The EIS results show that the main damage pattern of LIBs during micro-overcharge cycle is the active lithium loss when the cut-off voltage is between 4.3 V and 4.4 V. Lithium loss accounts for more than 80% damage proportion when LIBs cycling for more than 20 cycles.
Simulation Analysis of Sedimentation Separation of Suspended Solids Sewage in Oil Field Based on COMSOL
Authors: Ren Y L , He S W , Lei Q M , Gao S , Jiang M Z , Zhang R J , Wang Y
Published: May 2021

After oil and water separation, the produced sewage needs to be treated in a series of ways and injected into the ground if it reaches the discharge standard in oilfields. Sedimentation separation is one of the most important process. In order to study the law of settlement, a set of settlement simulation device was set up, and the raw wastewater was extracted from the oil production plant for settlement experiment, and the relevant data were gathered. Comsol software is used to model and analyse the model. Through comparing the calculation results with the experimental data, the velocity and concentration of liquid-solid two-phase medium change rules are concluded, which lays a foundation for further research on efficient treatment of oilfield sewage.
Study on the effect of home night lighting environment on students’ eyestrain and visual efficacy
Authors: Wang J.Q. , Fang Y.H. , Huang Y.X. , Chen J.N. , Luo X.Y.
Published: May 2021

China has the highest incidence rate of myopia, and the number of teenagers with myopia accounts for more than half of the total number of myopia in the world. In recent years, With the increase of youth night home learning time, the impact of the night lighting environment in the home learning space on eye health has become increasingly obvious. This paper selects 112 home learning spaces of middle school students to carry out the actual measurement of lighting environment parameters and the satisfaction survey of the lighting environment, and through comparative experiments to explore the effects of illuminance, color temperature and lighting methods on eyestrain and visual efficacy. This Study found that under mixed lighting conditions, when the color temperature is 4500k, the illuminance in the range of 500lx-750lx is beneficial to relieve eyestrain and improve visual efficacy; When the illuminance is 500lx, a low color temperature (3500k) can help relieve eyestrain, and a high color temperature (6000k) can improve visual efficacy better. In addition, mixed lighting is better than local lighting for relieving eyestrain and improving visual efficacy. The results will help improve the night lighting environment in the home learning space of middle school students.
Occurrence Frequencies and Regional Variations of Fire points in the southern China
Authors: Lai Guanglin , Xu Xiaoze , Su Haohui , Wang Qi , Zheng Wenjian
Published: May 2021

This paper employs Himawari-8 fire points data to analyze the annual, monthly and regional distribution of fire points in the five southern provinces (Guangdong, Guangxi, Yunnan, Guizhou, and Hainan). Results showed that from 2016 to 2020, the occurrence frequencies of fire points in Yunnan Province showed an increasing trend, while the occurrence frequencies in Guangdong Province showed a downward trend. The occurrence frequencies in Guizhou, Guangxi and Hainan did not change significantly. For the monthly scale, the occurrence frequencies of fire points are mainly concentrated in January-March in the southern China. The analysis results will provide reference for the prevention and control of fire accidents in the five southern provinces.
Discussion on Landscape and Greening Technology of Highway Structural Tunnel Entrance
Authors: Ming Liu , Zhiqiang Liu , Rongrong Qiang
Published: May 2021

Highway tunnel entrance is not only the exposed part of mountain in the tunnel engineering, but also an integral part of the highway breaking through the mountain. On the premise of ensuring the safety of tunnel entrance, it is important to realize the unity of safety and practical “stability” and landscape greening “beauty” of the expressway tunnel through reasonable aesthetic landscape greening design. In combination with the topographic and geomorphological conditions as well as the regional and humanistic conditions of the highway tunnel portal area, this paper introduces the cultural landscape and plant greening engineering of highway tunnel entrance by reference to the successful experience of tunnel entrance landscape greening, and puts forward the requirements for landscape and greening technology of highway tunnel entrance in accordance with the provisions of relevant regulations.
Value-added Service of Distribution Center on Integrated Cold Chain Performance
Authors: Mou Jin-Jin , Jiang Ying-Mei
Published: May 2021

Different from the previous articles on multi-echelon cold chain system, in addition to traditional transportation/distribution, warehousing and inventory control, DC value-added services, such as joint order processing, product processing and customizing, picking and assorting, joint distribution, etc. are employed to improve the performance of the cold chain system. Case study and sensitivity analysis demonstrate that (1) DC revenue is mainly from processing and customizing service for all kinds of products; (2) Of the value added services, picking and assorting cost has a significant effect on the total profit. These conclusions present good theoretical and managerial insights.
Study on Optimization of Port Railway Transportation Mode
Authors: Liu Donghui , Yu Zhouming , Jiang Minghui , Fan Runze , Wang Xiulei , Wang Zengjin , Lu Hongli
Published: May 2021

With the continuous development of port economy and the continuous promotion of industrial transformation and upgrading in China, the mode of gathering and distributing transportation in port area has gradually become the core factor to enhance the competitiveness of the whole logistics chain of port. It always play an important role in the port collection and distribution system. Especially for inland economic hinterland ports, it is of great significance to develop railway transportation and optimize port railway collection and distribution system. Based on the development and application of the theory of port railway transportation at home and abroad, this paper briefly analyzes the present situation and trend of port railway transportation mode. Combined with the demand characteristics of the current port railway transportation system and the problems that need to be further improved after the reform of freight organization, the form and task of optimizing the port railway transportation mode are clarified.
Treatment of simulated printing and dyeing wastewater using ozone microbubble
Authors: Nkudede Emmanuel , Sulemana Husseini , Zhang Bo , Zhu Kaida , Hu Shan , Gblinwon Roselyn Tehzee , Kosiba Anthony Adebayiga
Published: May 2021

Owing to its widespread and persistent usage, methylene blue (MB) is an environmental substance, mostly found in the printing and dyeing industry that raises concerns in the environment recently by posing significant threat to human life and the ecosystem as a whole. Thus, there is the need to effectively manage and treat the wastewater from these industries before reaching to the available water sources. Ozonation treatment is very efficient in treating printing and dyeing wastewater (MB) and can be greatly improved by using micro-bubble technology. Microbubble dissolution is an effective way to improve the rate of ozone mass transfer. To discover these properties, a method was used to improve the mass transfer of ozone microbubbles, which was used to effectively treat simulated printing and dyeing wastewater. We investigated the effects of pH, water temperature, ozone flow, and other conditions on the dissolution and attenuation properties of ozone in methylene blue microbubble solutions. Treatment of simulated printing and dyeing wastewater (methylene blue) was investigated under various initial pH and ozone flow rates. A catalytic exhibition was performed towards the decolorization of methylene blue (MB) concentrations and the corresponding COD removal efficiency. Ozone depletion and pH levels played key roles in MB degradation. Under high pH level of 11.01, the rate of removal of COD was 93.5%. Ozone dosage also has direct effect on COD removal efficiency and decolorization. Higher ozone flow rates, 0.4 L/min and 0.5 L/min recorded more than 94% degradation of COD thus very effective and efficient. Also, ozone flow rates 0.3 L/min, 0.4 L/min and 0.5 L/min with initial pH, 7.03, 6.63 and 6.36 decreased to 3.43, 3.49 and 3.44 after reaction processes which clearly shows that with high ozone dosage, pH reduces considerably.
Performance of ecological concrete-based ecological systems (ECBESs) for nitrogen removing from synthetic farmland drainage water
Authors: Xu Wei , Gao Song , Fang Weijian , Shi Chengcheng , Zhang Song , Gao Hongjian
Published: May 2021

Efficiency and mechanism of nitrogen removals by ecological concrete-based ecological systems (ECBESs) were investigated in this study. Results show that ECBES performed well on denitrification. Ecological concrete as matrix of the ecological was positive for nitrogen removing according to that the experimental ECBESs achieved a greater TN removal compared to the control system. This result was possibly attributable to a higher biomass and increased bacteria diversity in ECBESs, since ecological concrete could be a carrier of microorganism. Vegetation could further improve TN removals. Acorus calamus L. - ECBES, Ipomoea aquatica Forsk - ECBESs, Oenanthe javanica (Bl.) DC. - ECBES and Zizania aquatica - ECBES achieved an average TN removal of 67.87%, 81.93%, 76.18%, 66.22%, respectively, in a test cycle. Nitrogen transformation in the ECBESs indicated the occurrence of ammonification, nitrification and denitrification. Moreover, bacteria related to nitrogen transformation was identified from the bio-film immobilized on the ecological concrete.
Research on Technical Route Optimization and Energy-saving Characteristics of High-temperature Subcritical Retrofit
Authors: Wu He An , Zhong Feng Wei , Li Y.
Published: May 2021

In order to further reduce the power supply coal consumption rate for 300MW subcritical units, this paper will conduct a comprehensive analysis to improve the main steam and reheat steam parameters of those units based on the basic principles of thermodynamics, steam turbines and water pumps. The analysis shows that for the subcritical unit retrofit method that only raises the main steam and reheat steam temperature as the basic technical route has better feasibility. On this basis, combined with the actual system and working conditions of the 320MW subcritical unit, a simulation model of the entire plant’s thermal system is established for calculation and analysis. The calculation results show that the heat consumption rate of the high-temperature subcritical retrofit can reach 7526.7kJ/kWh. Combined with China Resources Xuzhou #3 unit high temperature subcritical comprehensive retrofit project (using high temperature subcritical transformation and equipped with special energy saving transformation), A comprehensive analysis of the performance of the unit after retrofit. The analysis shows that the coal consumption rate after the retrofit is reduced by 36g/kWh.
Enhanced technology of phytoremediation
Authors: Shuang Cui , Qing Han , Song Bai
Published: May 2021

The enhanced technology of phytoremediation has the advantages of low treatment cost, good purification effect, low environmental risk and environmental aesthetics. However, some hyperaccumulators grow slowly and their biomass is generally low; the activity of heavy metals in the soil is very low; the roots of plants are distributed in the surface of the soil, and the remediation effect of deep soil is poor; the nutrients of the soil to be repaired are seriously insufficient. It is necessary to take a series of strengthening measures to improve the efficiency of phytoremediation. The strengthening technologies of phytoremediation include chemical strengthening, microbial strengthening, animal strengthening, carbon dioxide strengthening, agronomic and management measures strengthening, etc.
Effect of fluorine on surface tension of CaO-SiO2-Al2O3-Na2O-CaF2 mold flux
Authors: Gao Qiang , Cao Longhu
Published: May 2021

The surface tension of mold flux is an important parameter for controlling the quality of continuous billet, affected deeply by the compositions of mold flux and temperature, andclosed related with the structure of mold flux. In the present study, the effect of CaF2and temperature on the surface tension of CaO-SiO2-Al2O3-Na2O-CaF2 mold flux melts is investigated by the pulling cylinder method; furthermore, the structure of melts is determined by FT-IR spectroscopy to analyze the change mechanism of surface tension. The results indicate that the variation of surface tension is in accord with that of structure of melts. The surface tension of melt decreases with the increase of CaF2 mass fraction, and this tendency becomes more apparent at higher temperature. The FT-IR spectra show thatboth the amount of Obandthe degree of structural polymerization of melts decrease as the CaF2 content increases. This is because the Si-Ob bonds in the [SiO4]-tetrahedrons are broken by F− and transformed into Si-F bonds, and the silicon-oxygen anions with more complex structure were depolymerized into silicon-oxygen anions containing fluorine with simpler structure, resulting in an increase of Si-F saturated bonds on the melt surface, and thusreducing the surface tension of melts.
Ophthalmic Outpatient and Inpatient Care Under Pandemic Conditions: Hygiene, Triage and New Challenges
Authors: Hattenbach Lars-Olof , Feltgen Nicolas , Eter Nicole , Al-Nawaiseh Sami , Chronopoulos Argyrios
Published: May 2021

Background The progression of the COVID-19 pandemic has caused significant changes in the environment for outpatient and inpatient care in ophthalmology, with limitations on access to medical care but also new observations and challenges. We now describe major developments in recent months and provide an outlook on the expected consequences.

Methods PubMed literature search, clinical survey.

Results To date, the course of the COVID-19 pandemic has been characterised by several new but overall rare ocular manifestations, the ophthalmological shared management of COVID-19 patients on intensive care units, and a significant decrease in case numbers, associated with an increase in case severity and relative proportion of emergencies, as a result of delayed presentation of patients and reduced treatment adherence. With the introduction of hygiene measures and infection control procedures, ophthalmic patient care was maintained – including emergencies and urgent treatments. Due to the extensive postponement of elective surgeries, scarce therapeutic and health care professional resources, and the prioritisation of critically ill patients from other specialties, there is a reasonable likelihood that urgent treatments will be delayed as infection rates rise.

Conclusion Outpatient and inpatient care in ophthalmology during the COVID-19 pandemic is primarily accompanied by additional organisational or medical challenges and a decline in case volume. Although to date emergency and urgent ophthalmic treatments have been maintained, long-term persistence of pandemic conditions will require additional strategies to provide continuation of ophthalmic care at the required level.
A Systematic Review of Economic Aspects of Service Interventions to Increase Anticoagulation Use in Atrial Fibrillation
Authors: Jones Nicholas R. , Crawford William , Yang Yaling , Hobbs F.D. Richard , Taylor Clare J. , Petrou Stavros
Published: May 2021

Objective To systematically identify and appraise existing evidence surrounding economic aspects of anticoagulation service interventions for patients with atrial fibrillation.

Methods We searched the published and grey literature up to October 2019 to identify relevant economic evidence in any health care setting. A narrative-synthesis approach was taken to summarise evidence by economic design and type of service intervention, with costs expressed in pound sterling and valued at 2017 to 2018 prices.

Results A total of 13 studies met our inclusion criteria from 1,168 papers originally identified. Categories of interventions included anticoagulation clinics (n = 4), complex interventions (n = 4), decision support tools (n = 3) and patient-centred approaches (n = 2). Anticoagulation clinics were cost-saving compared with usual care (range for mean cost difference: £188–£691 per-patient per-year) with equivalent health outcomes. Only one economic evaluation of a complex intervention was conducted; case management was more expensive than usual care (mean cost difference: £255 per-patient per-year) and the probability of its cost-effectiveness did not exceed 70%. There was limited economic evidence surrounding decision support tools or patient-centred approaches. Targeting service interventions at high-risk groups and those with suboptimal treatment was most likely to result in cost savings.

Conclusion This review revealed some evidence to support the cost-effectiveness of anticoagulation clinics. However, summative conclusions are constrained by a paucity of economic evidence, a lack of direct comparisons between interventions, and study heterogeneity in terms of intervention, comparator and study year. Further research is urgently needed to inform commissioning and service development. Data from this review can inform future economic evaluations of anticoagulation service interventions.
Adherence to the ‘Atrial Fibrillation Better Care’ Pathway in Patients with Atrial Fibrillation: Impact on Clinical Outcomes—A Systematic Review and Meta-Analysis of 285,000 Patients
Authors: Romiti Giulio Francesco , Pastori Daniele , Rivera-Caravaca José Miguel , Ding Wern Yew , Gue Ying Xuan , Menichelli Danilo , Gumprecht Jakub , Kozieł Monika , Yang Pil-Sung , Guo Yutao , Lip Gregory Y.H. , Proietti Marco
Published: May 2021

Objective The ‘Atrial fibrillation Better Care’ (ABC) pathway has been recently proposed as a holistic approach for the comprehensive management of patients with atrial fibrillation (AF). We performed a systematic review of current evidence for the use of the ABC pathway on clinical outcomes.

Methods and Results We performed a systematic review and meta-analysis according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. PubMed and EMBASE were searched for studies reporting the prevalence of ABC-pathway-adherent management in AF patients, and its impact on clinical outcomes (all-cause death, cardiovascular death, stroke, and major bleeding). Meta-analysis of odds ratio (OR) was performed with random-effects models; subgroup analysis and meta-regression were performed to account for heterogeneity. Among the eight studies included, we found a pooled prevalence of ABC-adherent management of 21% (95% confidence interval, CI: 13–34%), with a high grade of heterogeneity, explained by the increasing adherence to each ABC criterion. Patients treated according to the ABC pathway showed a lower risk of all-cause death (OR: 0.42; 95% CI: 0.31–0.56), cardiovascular death (OR: 0.37; 95% CI: 0.23–0.58), stroke (OR: 0.55; 95% CI: 0.37–0.82) and major bleeding (OR: 0.69; 95% CI: 0.51–0.94), with moderate heterogeneity. Prevalence of comorbidities was moderators of heterogeneity for all-cause and cardiovascular death, while longer follow-up was associated with increased effectiveness for all outcomes.

Conclusion Adherence to the ABC pathway was suboptimal, being adopted in one in every five patients. Adherence to the ABC pathway was associated with a reduction in the risk of major adverse outcomes.
Updates and Advances: Pediatric Musculoskeletal Infection Imaging Made Easier for Radiologists and Clinicians
Authors: Furman Michael S. , Restrepo Ricardo , Kritsaneepaiboon Supika , Laya Bernard F. , Plut Domen , Lee Edward Y.
Published: May 2021

Infants and children often present with a wide range of musculoskeletal (MSK) infections in daily clinical practice. This can vary from relatively benign superficial infections such as cellulitis to destructive osseous and articular infections and life-threatening deep soft tissue processes such as necrotizing fasciitis. Imaging evaluation plays an essential role for initial detection and follow-up evaluation of pediatric MSK infections. Therefore, a clear and up-to-date knowledge of imaging manifestations in MSK infections in infants and children is imperative for timely and accurate diagnosis that, in turn, can result in optimal patient management. This article reviews an up-to-date practical imaging techniques, the differences between pediatric and adult MSK infections, the spectrum of pediatric MSK infections, and mimics of pediatric MSK infections encountered in daily clinical practice by radiologists and clinicians.