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Abstract

In view of the high cost and difficulty of ensuring the accuracy in the measurement of fire smoke velocity, the measurement system developed using platinum resistance temperature detectors and an 8-bit microcontroller, is used to realize the fast measurement of high-temperature fire smoke velocity. The system is based on the thermodynamic method and adopts the Kalman filter algorithm to process the measurement data, so as to eliminate noise and interference, and reduce measurement error. The experimental results show that the Kalman filter algorithm can effectively improve the measurement accuracy of fire smoke velocity. It is also shown that the system has high measurement accuracy, short reaction time, low cost, and is characterized by high performance in the measurement of high-temperature smoke velocity in experiments and practice.
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Authors and Affiliations

Haoyu Wang
1

  1. Department of Fire Engineering, China Fire and Rescue Institute, Nanyan 4, Changping District, 102202, Beijing, China
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Abstract

Analog circuits need more effective fault diagnosis methods. In this study, the fault diagnosis method of analog circuits was studied. The fault feature vectors were extracted by a wavelet transform and then classified by a generalized regression neural network (GRNN). In order to improve the classification performance, a wolf pack algorithm (WPA) was used to optimize the GRNN, and a WPA-GRNN diagnosis algorithm was obtained. Then a simulation experiment was carried out taking a Sallen–Key bandpass filter as an example. It was found from the experimental results that the WPA could achieve the preset accuracy in the eighth iteration and had a good optimization effect. In the comparison between the GRNN, genetic algorithm (GA)-GRNN and WPA-GRNN, the WPA-GRNN had the highest diagnostic accuracy, and moreover it had high accuracy in diagnosing a single fault than multiple faults, short training time, smaller error, and an average accuracy rate of 91%. The experimental results prove the effectiveness of the WPA-GRNN in fault diagnosis of analog circuits, which can make some contributions to the further development of the fault diagnosis of analog circuits.

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Authors and Affiliations

Hui Wang
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Abstract

Due to the characteristics of color vegetation canopy images which have multiple details and Gaussion noise interference, the adaptive mean filtering (AMF) algorithm is used to perform the denoising experiments on noised images in RGB and YUV color space. Based on the single color characteristics of color vegetation canopy images, a simplified AMF algorithm is proposed in this paper to shorten the overall running time of the denoising algorithm by simplifying the adaptive denoising processing of the component V, which contains less image details. Experimental results show that this method can effectively reduce the running time of the algorithm while maintaining a good denoising effect.

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Authors and Affiliations

C. Wang
Y. Liu
P. Wang
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Abstract

The purpose of this paper is to discuss the distinguished properties of by-names as forms different from official ones, to analyze their structural and semantic features and to search for their historical evidence. By-names of Chinese places should not be defined as unusual and informal, since actually in many cases by-names are formal and very common in China nowadays. By-names are generally bestowed on important places (mostly cities) that win the public interest. Most of them have two structural parts, the front specific parts are determiners / qualifiers and the back ones are generics. The generics generally are: cheng 城 ‘town / city’, du 都 ‘capital’, jiang 江 ‘river’, shan 山 ‘mountain’, dao 岛 ‘island’ etc. The lexical meanings of lexical items forming specific parts of by-names mainly refer to animals, plants, minerals, local manufactured products, climate and natural scenery, geographical location, humans, areas, etc. Chinese contemporary by-names, used on various occasions, vary in frequency and stability. The by-names discussed in the paper only account for a small proportion and are listed just due to their relatively high frequency, stability and acceptability.

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Authors and Affiliations

Xiaoqiong Wang
Irena Kałużyńska
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Abstract

This article explores investment protection under Chinese international investment agreements (IIAs), particularly under the China-Poland bilateral investment treaty (BIT). As a state that both imports and exports foreign direct investment, China currently promotes balanced and safeguarded BITs that protect its increasing overseas investments and preserves the necessary space to regulate in the public interest. The Chinese government remains reluctant to be directly involved in investment arbitration as a respondent, while Chinese investors are active in taking advantage of the IIAs’ regime. When compared to China’s recent treaty practice and new developments in global investment governance, the China-Poland BIT is relatively outdated in terms of investment protection, promotion, social clauses, and dispute settlement. In terms of the investment protection effects of BITs, China is seemingly in a more urgent position to update the China-Poland BIT. However, if we evaluate the overall effects of a modernized BIT on investment promotion, regulation, and dispute settlement, an updated China-Poland BIT will fit the interests of both the Polish and Chinese governments. Notwithstanding the on-going negotiation between the EU and China, this article aims, along with presenting the Chinese practice regarding BITs, to describe de lege lata the state of protection offered to Chinese and Polish investors under the China-Poland BIT.

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Authors and Affiliations

Peng Wang
Maciej Żenkiewicz
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Abstract

The two-dimensional distribution of gas-solid flow parameters is a great research significance to reflect the actual situation in industry. The commonly used method is the ultrasonic tomography method, in which multiple probes are arranged at various angles, or the measurement device is rotated as that in medicine, but in most industrial situations, it is impossible to install probes at all angles or rotate the measured pipe. The backscattering method, however, uses only one transducer to both transmit and receive signals, and the twodimensional information is obtained by only rotating the transducer. Ultrasound attenuates greatly in the air, and the attenuation changes with frequency. Therefore, COMSOL is used to study the reflection of particles with different radii in the air to ultrasound with various frequencies. It is found that the backscattering equivalent voltage is the largest when the product of ultrasonic frequency and particle radius is about 27.78 Hz �� m, and the particle concentration of 30% causes the strongest backscattering. The simulated results are in good agreement with the Faran backscattering model, which can provide references for selecting the appropriate frequency and obtaining the concentration when measuring gas-solid two-phase flow with the ultrasonic backscattering method.
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Authors and Affiliations

Jinhui Fan
1
Fei Wang
1

  1. State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou, 310027, China
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Abstract

The head-related transfer function (HRTF) is dependent on the position of the sound source (both direction and distance) and is also affected by individual anatomical parameters. Individualized HRTFs have been shown to affect the perception of sound direction, but have not been considered in distance perception. This work aims to discover, by means of psychoacoustic experiments for a virtual reproduction system through a pair of in-ear headphones, the effect of individualized HRTF on auditory distance perception for a nearby sound source. The individualized HRTFs of six subjects and the non-individualized HRTFs of a mannequin at seven distances between 0.2 and 1.0 m and five lateral azimuths between 45X and 135X in the horizontal plane were processed with white noise to generate binaural signals. Further, the individualized and non-individualized HRTFs were used in the auditory distance perception experiments. Results of distance perception show that the variance of distance perception results among subjects is significant, the reason could be the stimuli are lack of dynamic cue and early reflections, or the auditory difference of distance perception among subjects. However, via the analyses of mean slope of perceptual distance and correlation between the perceptual and real distance, we find that the individualized HRTF cue has insignificant influence on distance perception.

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Authors and Affiliations

Guangzheng Yu
Liliang Wang
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Abstract

Wave motion in pipe bends is much more complicated than that in straight pipes, thereby changing considerably the propagation characteristics of guided waves in pipes with bends. Therefore, a better understanding of how guided waves propagate in pipe bends is essential for inspecting pipelines with bends. The interaction between a pipe bend and the most used non-dispersive torsional mode at low frequency in a small-bore pipe is studied in this paper. Experiments are conducted on a magnetostrictive system, and it is observed that T(0,1) bend reflections and mode conversions from T(0,1) to F(1,1) and F(2,1) occur in the pipe bend. The magnitude of the T(0,1) bend reflections increases with increasing propagation distance and excitation frequency. The amplitude of the mode-converted signals also increases with increasing propagation distance, but it decreases with increasing excitation frequency. Because of their longer bent path, the test signals for a pipe bend with a bending angle of 180X are much more complicated than those for one with a bending angle of 90X. Therefore, it is even more difficult to scan a bent pipe with a large bending angle. The present findings provide some insights into how guided waves behave in pipe bends, and they generalize the application of guided-wave inspection in pipelines.

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Authors and Affiliations

Wenjun Wu
Junhua Wang
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Abstract

A spinal code is the type of rateless code, which has been proved to be capacity- achieving over both a binary symmetric channel (BSC) and an additive white Gaussian noise (AWGN) channel. Rateless spinal codes employ a hash function as a coding kernel to generate infinite pseudo-random symbols. A good hash function can improve the perfor- mance of spinal codes. In this paper, a lightweight hash function based on sponge structure is designed. A permutation function of registers is a nonlinear function. Feedback shift registers are used to improve randomness and reduce bit error rate (BER). At the same time, a pseudo-random number generator adopts a layered and piecewise combination mode, which further encrypts signals via the layered structure, reduces the correlation between input and output values, and generates the piecewise random numbers to compensate the shortcoming of the mixed linear congruence output with fixed length. Simulation results show that the designed spinal code with the lightweight hash function outperforms the original spinal code in aspects of the BER, encoding time and randomness.

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Authors and Affiliations

Lina Wang
Xinran Li
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Abstract

As the capacity and scale of distribution networks continue to expand, and distributed generation technology is increasingly mature, the traditional fault location is no longer applicable to an active distribution network and "two-way" power flow structure. In this paper, a fault location method based on Karrenbauer transform and support vector machine regression (SVR) is proposed. Firstly, according to the influence of Karrenbauer transformation on phase angle difference before and after section fault in a low-voltage active distribution network, the fault regions and types are inferred preliminarily. Then, in the feature extraction stage, combined with the characteristics of distribution network fault mechanism, the fault feature sample set is established by using the phase angle difference of the Karrenbauer current. Finally, the fault category prediction model based on SVR was established to solve the problem of a single-phase mode transformation modulus and the indistinct identification of two-phase short circuits, then more accurate fault segments and categories were obtained. The proposed fault location method is simulated and verified by building a distribution network system model. The results show that compared with other methods in the field of fault detection, the fault location accuracy of the proposed method can reach 98.56%, which can enhance the robustness of rapid fault location.
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Authors and Affiliations

Siming Wang
1
Zhao Kaikai
1

  1. School of Automation and Electrical Engineering, Lanzhou Jiaotong University, China
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Abstract

Compared with traditional cellular networks, wireless ad hoc networks do not have trusted entities such as routers, since every node in the network is expected to participate in the routing function. Therefore, routing protocols need to be specifically designed for wireless ad hoc networks. In this work, we propose an authenticated routing protocol based on small world model (ARSW). With the idea originating from the small world theory, the operation of the protocol we proposed is simple and flexible. Our simulation results show the proposed ARSW not only increases packet delivery ratio, but also reduces packet delivery delay. In particularly, Using authentication theory, the proposed ARSW improves communication security.
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Bibliography

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Authors and Affiliations

Daxing Wang
1
Leying Xu
1

  1. College of Mathematics and Finance, Chuzhou University
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Abstract

A novel process to recover lithium and manganese oxides from a cathode material (LiMn2O4) of spent lithium-ion battery was attempted using thermal reaction with hydrogen gas at elevated temperatures. A hydrogen gas as a reducing agent was used with LiMn2O4 powder and it was found that separation of Li2O and MnO was taken place at 1050°C. The powder after thermal process was washed away with distilled water and only lithium was dissolved in the water and manganese oxide powder left behind. It was noted that manganese oxide powder was found to be 98.20 wt.% and the lithium content in the solution was 1,928 ppm, respectively.
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Authors and Affiliations

Jei-Pil Wang
1

  1. Pukyong National University, Department of Metallurgical Engineering, Busan, Republic of Korea
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Abstract

Highly immunogenic nucleotide fragments from 3 genes of Mycoplasma hyopneumoniae strain 232 were selected using information software technology. After repeating each fragment three times, a total of 9 nucleotide fragments were joined together to form a new nucleotide sequence called Mhp2321092bp. Mhp2321092bp was directly synthesized and cloned into a pET100 vector and expressed in Escherichia coli. After purification, the proteins were successfully validated by SDS-PAGE and Western blotting using mouse His-tag antibody and pig anti-Mhp serum. BALB/c mice were intraperitoneally injected with purified proteins in the high-dose (100 μg), medium-dose group (50 μg) and low-dose (10 μg) groups. Mice in each group were injected on day 1, day 8 and day 15 of feeding, respectively. Serum samples were collected from all mice on the day before immunization and on day 22 after immunization. The antibody level in the mouse serum was detected using western blotting using purified expressed proteins as antigens. IL-2, TNF-α and IFN-γ were simultaneously detected in the mouse serum by ELISA. The results showed that the 60 kDa protein was successfully expressed and reacted specifically with the specific serum Mhp His-Tag mouse monoclonal antibody and pig anti-Mhp serum. From day 0 to day 22 of immunization, IFN-γ increased from 269.52 to 467.74 pg/mL, IL-2 increased from 14.03 to 145.16 pg/mL, and TNF-α increased from 6.86 to 12.37 pg/mL. The IgG antibody in mice increased significantly from 0 day to day 22 after immunization. This study suggests that the expressed recombinant protein may serve as one of the novel vaccine candidates for Mhp.
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Authors and Affiliations

J. Li
1
G. Wang
1

  1. College of Veterinary Medicine, Hunan Agricultural University, Nongda road 1#, Changsha, Hunan, 410128, China
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Abstract

Ti-containing steel weld metals with Al contents of 0.01-0.085% were prepared. The effects of Al contents on the inclusions evolution were investigated by means of thermodynamic calculations coupled with electron probe micro-analyses and transmission electron microscopy. The results show that the inclusions in the 0.01% Al weld metal are mainly composed of ilmenite with some amounts of (Mn-Si-Al)-oxide and titanial_spinel. When Al content is increased up to 0.035%, a more amount of corundum and a small amount of pseudobrookite are formed. In 0.085% Al weld metal, the (Mn-Si-Al)-oxide disappears completely, and the inclusions contain a substantial amount of corundum, in addition to a minimal amount of pseudobrookite. Ti3O5, MnTi2O4 and MnTiO3 are the primary constituents of pseudobrookite, titanial_spinel and ilmenite, respectively. Titanial_spinel and ilmenite have higher amounts of Mn, but lower Ti levels compared with pseudobrookite. In the case of presence of a considerable amounts of titanial_spinel and ilmenite, Mn-depleted zone is formed in matrix around the inclusions.

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Authors and Affiliations

Bingxin Wang
Yingtian Jiang
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Abstract

Using colloid water as a covering for explosives can improve the energy efficiency for explosive welding, while its effects on bonding properties remain unclear. Here, by employing titanium/steel as a model system, the effect of covering thickness on microstructures and mechanical properties of the bonding interface was systematically investigated. It was found that all the welds displayed wavy interfaces, and the wave size increased with increasing covering thickness. Vortices characterized by solidified melt zones surrounded by strongly deformed parent materials, were only formed for the welds performed with a covering. Moreover, with increasing covering thickness, both the tensile strength and the elongation of the titanium/steel plate decreased, and the failure mode changed from ductile to cleavage fracture, gradually. In the tensile-shear tests, all the fractures took place in titanium matrix without separation at interface, indicating that the titanium/steel interfaces had an excellent bonding strength. The micro-hardness decreased with increasing distance from the interface, and this trend was more remarkable for a thicker covering. The micro-hardness inside the solidified melt zones was far higher than that observed in strain-hardened layers of the parent metal, due to formation of hard intermetallic compounds.
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Authors and Affiliations

Fei Wang
1
Ming Yang
2

  1. Anhui University of Science and Technology State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines,Huainan, Anhui Province, China
  2. Nanjing University of Science and Technology, National Key Laboratory of Transient Physics, Nanjing, 210094, China
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Abstract

The numerical solutions of stress and strain components on the critical plane of tungsten carbide coating were solved based on the critical plane method in three-dimensional coordinate system, and accordingly three strain energy density parameters (Smith-Watson-Topper, Nita-Ogatta-Kuwabara and Chen parameters) were determined to reveal the fretting fatigue characteristics of tungsten carbide coating. In order to predict the fretting fatigue life based on the strain energy density criterion, the expressions between the strain energy density parameter and the fretting fatigue life was obtained experimentally. After the comparison of the three strain energy parameters, it was found that all three parameters could accurately predict the crack initiation position, but only the Smith-Watson-Topper parameters could accurately predict the crack initiation angle. The effects of cyclic load, normal load and friction coefficient on fretting fatigue damage behaviors were discussed by using the Smith-Watson-Topper criterion. The results show that the fretting fatigue life decreases with the increase of cyclic load; an increase in the normal contact load will cause the Smith-Watson-Topper damage parameters more concentrated at the outer edge of the bridge foot; a decrease in the friction coefficient will increase the Smith-Watson-Topper damage parameters in the middle of the contact surface.
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Authors and Affiliations

Xin Zeng
1 2
Xiaoxiao Wang
1 2
Xuecheng Ping
1 2
Renjie Wang
1 2
Tao Hu
3

  1. Tianjin University of Science and Technology, School of Mechanical Engineering, Tianjin 300222, China
  2. Tianjin University of Science and Technology, Tianjin Key Laboratory of Integrated Design and Online Monitoring of Light Industry and Food Engineering Machinery and Equipment, Tianjin 300222, China
  3. Shanghai Xifa Business Consult ing Co., Ltd., Shanghai 200232, China
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Abstract

In view of the increasing scarcity of bauxite resources in China, the high energy consumption and high pollution of electrolytic aluminum, and the requirements for energy conservation and environmental protection, aluminum recycling and high-value utilization of its derivatives have evolved into a crucial development requirement for the aluminum industry in the future. As an important part of the development of recycled aluminum resources, the high-value application of scrap aluminum cans has always been a hot research topic in various recycled aluminum processing enterprises and scientific research units. The traditional regeneration system of waste cans includes a series of complex technological processes such as pretreatment, paint removal, smelting system and casting system, which is difficult to control in the middle of the process. Most of the recycled scrap aluminum cans are cast and downgraded for later use, except for a part of them used as alloy materials for new cans. In this paper, combined with the research on the preparation of metal aluminum alkoxide, combined with recrystallization heat conduction to further study the effective dissolution or adsorption how to remove impurity elements to obtain high-purity aluminum alcohol salt mechanism research, and thermal effect of alcohols with different carbon chains on the synthesis of high-purity aluminum alkoxide was further investigated. Moreover, the changes in morphology and pore size distribution of hydrolyzed alumina precursor materials under different hydrothermal temperature conditions were discussed by means of the alkoxide hydrolysis-sol-gel process. Eventually, the aluminum alkoxide was obtained by the reaction of waste cans with isopropanol and heavy crystal thermal conductivity, and the high-purity aluminum alkoxide was purified by vacuum distillation. Under the hydrothermal condition of 160°C, the high-purity alumina material with a purity of 99.99% and an original crystal size of 200nm was prepared.
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Bibliography

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Authors and Affiliations

Chengmin Wang
1
Anatoly Politov
2
Xiuhui Wang
1
Jinlong Yang
3

  1. Dalian Jiaotong University, China
  2. Institute of Solid State Chemistry and Mechanochemistry, Russia
  3. State Key Laboratory of New Ceramics & Fine Processing, China
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Abstract

Acoustical analysis of snoring provides a new approach for the diagnosis of obstructive sleep apnea hypopnea syndrome (OSAHS). A classification method is presented based on respiratory disorder events to predict the apnea-hypopnea index (AHI) of OSAHS patients. The acoustical features of snoring were extracted from a full night’s recording of 6 OSAHS patients, and regular snoring sounds and snoring sounds related to respiratory disorder events were classified using a support vector machine (SVM) method. The mean recognition rate for simple snoring sounds and snoring sounds related to respiratory disorder events is more than 91.14% by using the grid search, a genetic algorithm and particle swarm optimization methods. The predicted AHI from the present study has a high correlation with the AHI from polysomnography and the correlation coefficient is 0.976. These results demonstrate that the proposed method can classify the snoring sounds of OSAHS patients and can be used to provide guidance for diagnosis of OSAHS.

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Authors and Affiliations

Can Wang
Jianxin Peng
Xiaowen Zhang
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Abstract

Alveolar macrophages (AMs) are not only important immune cell of the host, but also important target cell of a variety of respiratory pathogens. They play an important role in defense against pathogen invasion and in maintaining tissue balance. Interferon (IFN)-γ is a well known multipotent cytokine that has antiviral and antibacterial immune activity and enhances antigen presentation. To better reveal the biological processes of porcine AMs activated by IFN-γ, transcriptomic analysis was performed using Illumina HiSeqTM technique. The results identified 2,248 differentially expressed genes (DEGs), of which 753 were upregulated and 1,495 were downregulated, in porcine AMs 12 h after IFN-γ stimulation, compared with mock-treated porcine AMs. A gene ontology function enrichment analysis of these DEGs indicated that these genes were significantly enriched in functional clusters such as immune response, defense response, and intracellular signaling cascades. Analyzing the Kyoto Encyclopedia of Genes and Genomes pathways of the DEGs showed that these genes are mainly involved in cytokine–cytokine receptor interactions, alpha linolenic acid metabolism, and the RIG-I-like receptor signaling pathway. This study shows that a massive gene expression change occurred in porcine AMs following IFN-γ stimulation, which is critical for understanding the mechanisms of IFN-γ-mediated macrophage activation and immune regulation.
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Authors and Affiliations

Q. Liu
1
H.-Y. Wang
1

  1. Nanchong Key Laboratory of Disease Prevention, Control, and Detection in Livestock and Poultry, Nanchong Vocational and Technical College, Nanchong 637131, China
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Abstract

Object tracking based on Siamese networks has achieved great success in recent years, but increasingly advanced trackers are also becoming cumbersome, which will severely limit deployment on resource-constrained devices. To solve the above problems, we designed a network with the same or higher tracking performance as other lightweight models based on the SiamFC lightweight tracking model. At the same time, for the problems that the SiamFC tracking network is poor in processing similar semantic information, deformation, illumination change, and scale change, we propose a global attention module and different scale training and testing strategies to solve them. To verify the effectiveness of the proposed algorithm, this paper has done comparative experiments on the ILSVRC, OTB100, VOT2018 datasets. The experimental results show that the method proposed in this paper can significantly improve the performance of the benchmark algorithm.
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Authors and Affiliations

Zhentao Wang
1
Xiaowei He
1
Rao Cheng
1

  1. College of Mathematics and Computer Science, Zhejiang Normal University, Jinhua, Zhejiang, 321000, China
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Abstract

The rapid and accurate detection and identification of coal gangue is one of the premises and key technologies of the intelligent separation of coal gangue, which is of considerable importance for the separation of coal gangue. Focusing on the problems in the current deep learning algorithms for the detection and recognition of coal gangue, such as large model memory and slow detection speed, a rapid detection method for lightweight coal gangue is proposed. YOLOv3 is taken as the basic structure and improved. The MobileNetv2 lightweight feature extraction network is selected to replace Darknet53 as the main network of the detection algorithm to improve the detection speed. Spatial pyramid pooling (SPP) is added after the backbone network to convert different feature maps into fixed feature maps in order to improve the positioning accuracy and detection capability of the algorithm, thereby obtaining the lightweight network MS-YOLOV3. The experimental equipment was set up and multi-condition coal and gangue datasets were constructed. The model was trained and the identification and positioning results of the model were tested under different sizes, illumination intensities and various working conditions, and compared with other algorithms. Experimental results show that the proposed algorithm can detect the coal gangue quickly and accurately, with an mAP of 99.08%, a speed of 139 fps and a memory occupation of only 9.2 M. In addition, the algorithm can effectively detect mutually stacking coal and gangue of different quantities and sizes under different lights with high confidence and with a certain degree of environmental robustness and practicability. Compared with the YOLOv3, the performance of the proposed algorithm is significantly improved. Under the premise that the accuracy is unchanged, the FPS increases by 127.9% and the memory decreases by 96.2%. Therefore, the MS-YOLOv3 algorithm has the advantages of small memory, high accuracy and fast speed, which can provide online technical support for the detection and identification of coal and gangue.
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Authors and Affiliations

Deyong Li
1
Guofa Wang
2
ORCID: ORCID
Shuang Wang
3
Wenshan Wang
3
Ming Du
3

  1. State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines, Anhui University of Science and Technology, Huainan 232001, China
  2. Collaborative Innovation Center for Mine Intelligent Technology and Equipment, Anhui University of Science and Technology, Huainan 232001, China
  3. China Coal Technology Engineering Group Coal Mining Research Institute, Beijing 100013, China
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Abstract

To promote the application of aeolian sand resources for steel-concrete composite structures, an aeolian sand reinforced concrete column with I-shaped structural steel is proposed in this study. Four specimens are designed and manufactured with different replacement rates of aeolian sand. The seismic behaviour and damage evolution process of the specimens are studied by low-cycle repeated loading tests. Based on the test results, the mechanical characteristics, failure modes, hysteresis curves, skeleton curves, energy dissipation capacity, displacement ductility, and stiffness degradation of the specimens with different replacement rates of aeolian sand are analysed. In addition, the effects of the design parameters on the seismic behaviour of the specimens are also studied. The results show that the indexes of the seismic behaviour can be significantly improved by adding steel. Moreover, a revised damage model is proposed, to better reflect the evolution law of seismic damage of aeolian sand reinforced concrete columns with steel. The proposed model can provide an important reference for seismic damage assessment of the columns.

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Authors and Affiliations

Yaohong Wang
Heyan Wang
Yanpeng Wang
Meng Zhao
Jin Qi
Guangzong Huo
Peiqi Liu
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Abstract

To explore the role of Toll-like receptors (TLRs) and interferon (IFN) in the innate immunity against porcine epidemic diarrhea virus (PEDV), we detected the expression of TLR genes in PEDV-infected IPEC-J2 cells by real-time PCR. We also detected the level of interferon α (IFN-α) and interferon γ (IFN-γ) by enzyme-linked immunosorbent assay (ELISA). Results showed that IPEC-J2 cells exhibited a clear pathological change after PEDV infection at 24 h. In addition, TLR7, TLR9 and TLR10 expressions were significantly upregulated in PEDV-infected IPEC-J2 cells at 24 h. Interestingly, the expression patterns of TLR2 and TLR4 were consistent at different stages of PEDV infection. The expression level of TLR3 decreased significantly with the increase of infection time, but the expression levels of TLR5 and TLR8 genes at 6 h and 12 h were significantly lower than those in the control group (p<0.01). There were significant correlations among the expression levels of TLR genes (p<0.05). Cytokine detection showed that the secretion level of IFN-α in the PEDV-infected group was significantly higher than that in the control group (p<0.01), and IFN-γ at 6 h and 12 h after PEDV infection was significantly higher than that in control group (p<0.01). Therefore, our results suggest that PEDV infection can induce innate immune responses in intestinal porcine jejunum epithelial cells, leading to changes in the expression of Toll-like receptors, and can regulate the resistance to virus infection by affecting the release levels of downstream cytokines.

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Authors and Affiliations

F. Wang
S.Q. Wang
H.F. Wang
Z.C. Wu
W.B. Bao
S.L. Wu
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Abstract

A numerical model of the high-speed train carriage fire is established in this study. The influence of ceilings, sidewalls, luggage racks, seats, and floors on the heat release rate (HRR) of the high-speed train is studied by numerical methods. The results indicate that the heat release rate per unit area (HRRPUA) of ceiling and seat material dramatically influences the peak HRR and the time to peak HRR of train carriage fire. When the peak HRRPUA of interior ceiling material 1 decreases from 326 to 110 kW/m2, the peak HRR of the high-speed train fire decreases from 36.4 to 16.5 MW, with a reduction ratio of 54.7%. When seat materials with low HRRPUA are used, the peak HRR reduction ratio is 44.8%. The HRRPUA of the sidewall, luggage rack, and floor materials has little effect on the peak HRR of the carriage fire. However, the non-combustible luggage rack can delay the time when the HRR reaches its peak.
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Authors and Affiliations

Yuanlong Zhou
1
Haiquan Bi
2
Honglin Wang
2

  1. University of Science and Technology of China, State Key Laboratory of Fire Science, Hefei, Anhui 230026, China
  2. Southwest Jiaotong University, School of Mechanical Engineering, Chengdu 610031, China

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