bluuebunny/crossref_metadata_2025 huggingface dataset:
The initiation of smouldering peat fire by a glowing firebrand
Authors: Lin Shaorun , Zhang Tianhang , Huang Xinyan , Gollner Michael J.
Published: April 2024

Background Wildfires represent a significant threat to peatlands globally, but whether peat fires can be initiated by a lofted firebrand is still unknown. Aims We investigated the ignition threshold of peat fires by a glowing firebrand through laboratory-scale experiments. Methods The oven-dried weight (ODW) moisture content (MC) of peat samples varied from 5% ODW to 100% ODW, and external wind (ν) with velocities up to 1 m/s was provided in a wind tunnel. Key results and conclusions When MC < 35%, ignition is always achieved, regardless of wind velocity. However, if MC is between 35 and 85%, an external wind (increasing with peat moisture) is required to increase the reaction rate of the firebrand and thus heating to the peat sample. Further increasing the MC to be higher than 85%, no ignition could be achieved by a single laboratory firebrand. Finally, derived from the experimental results, a 90% ignition probability curve was produced by a logistic regression model. Implications This work indicates the importance of maintaining a high moisture content of peat to prevent ignition by firebrands and helps us better understand the progression of large peat fires.
Modification of the Rothermel model parameters – the rate of surface fire spread of Pinus koraiensis needles under no-wind and various slope conditions
Authors: Geng Daotong , Yang Guang , Ning Jibin , Li Ang , Li Zhaoguo , Ma Shangjiong , Wang Xinyu , Yu Hongzhou
Published: April 2024

Background The prediction accuracy for the rate of surface fire spread varies in different regions; thus, increasing the prediction accuracy for local fuel types to reduce the destructive consequences of fire is critically needed. Aims The objective of this study is to improve the Rothermel model’s accuracy in predicting the ROS for surface fuel burning in planted forests of Pinus koraiensis in the eastern mountains of north-east China. Methods Fuel beds with various fuel loads and moisture content was constructed on a laboratory burning bed, 276 combustion experiments were performed under multiple slope conditions, and the ROS data from the combustion experiments were used to modify the related parameters in the Rothermel model. Results The surface fire spread rate in Pinus koraiensis plantations was directly predicted using the Rothermel model but had significant errors. The Rothermel model after modification predicted the following: MRE = 25.09%, MAE = 0.46 m min−1, and R2 = 0.80. Conclusion The prediction accuracy of the Rothermel model was greatly enhanced through parameter tuning based on in-lab combustion experiments Implications This study provides a method for the local application of the Rothermel model in China and helps with forest fire fighting and management in China.
Fault severity recognition in axial piston pumps using attention-based adversarial discriminative domain adaptation neural network
Authors: Shao Yuechen , Chao Qun , Xia Pengcheng , Liu Chengliang
Published: April 2024

Axial piston pumps are the ‘hearts’ of hydraulic systems whose fault recognition is necessary for the safety and reliability of hydraulic equipment. These pumps operate under different operating conditions and the fault recognition model trained at one operating point cannot be applicable at another operating point due to the problem of domain shifts. This paper proposes a transfer learning method for the fault severity recognition of axial piston pumps based on adversarial discriminative domain adaptation fused with a convolutional channel attention module. First, a convolutional neural network is pre-trained with labeled vibration data from the source domain, and a convolutional channel attention module is added to assign weights to different convolution kernels. Second, the trained source model is transferred to the target domain, and its parameters are updated by an adversarial training process between the labeled source data and the unlabeled target data. Finally, vibration data are collected from an axial piston pump at different fault levels under various operating conditions to validate the proposed method. Experimental results indicate that the proposed method achieves an average recognition accuracy of 98.3% and outperforms some other transfer learning methods by a large margin.
Ultra-sensitive detection of triethylamine (TEA) using LMR/LSPR based fiber optic probe
Authors: Jyoti  , Verma R K
Published: April 2024

The excessive intake and inhalation of Triethylamine (TEA), which is an essential ingredient of pharmaceuticals, emulsifiers, dyestuff, soaps, rubber production etc, can cause health hazards such as blue haze, blurry vision, nausea, headache, and faintness; and to prevent the human beings from these hazards, it is crucial to detect TEA level. The present study explores the detection of TEA, using ZnO nanorods and porphyrin coated optical fiber probes. These probes have been synthesized and the topography, composition and morphology of different layers have been confirmed using FESEM, EDX and NMR characterizations. The sensitivity of this hybrid material-based probe has been estimated and was found to be 7-fold to the sensitivity of the metal oxide (ZnO nanorods) based fiber optic probe. The selectivity study has also been performed and it was observed that the analyte TEA has highest response (83.495 nm shift in peak wavelength) compared to other analytes such as the ethanol. This hybrid material-based fiber-optic probe offers the better selectivity and sensitivity for TEA and provides a very quick response time.
Enhancing quantum coherence in multiqubit-interacting system
Authors: Zhao Wen-Jing , Xu Kai , Sun Ji-Yang , Li Zai-Dong , Liu Wu-Ming
Published: April 2024

We propose a quantum coherence protection scheme for a two-qubit system by considering the exact evolution of multi-interacting qubits in a common reservoir. We find that the l
1 norm of coherence and the relative entropy of coherence can be noticeably enhanced by increasing the number of qubits in the weak/strong system-environment coupling regime, which contrasts sharply with the impact of coupling between qubits. Moreover, in the infinite-time limit, all the coherence measures reach their steady values which are determined only by the number of qubits.
Blaze-angle led dark-blue iridescence and superhydrophobicity features of non-morpho Euploea midamus butterfly wing scale
Authors: Das Bikash K , Dubey Mahesh C , Mohanta Dambarudhar
Published: April 2024

We report on backlit iridescent blue structural coloration as well as superhydrophobicity in a non-morpho butterfly of Euploea midamus (blue-spotted crow) belonging to the Lepidoptera order. Select forewing and hindwing parts were characterized by employing optical microscopy, field emission electron microscopy, UV–vis-NIR spectrophotometry, and an advanced contact angle meter. As substantiated from variable incident angle reflectance spectra and chromaticity plots, the apparent visual effect is most pronounced in the forewing case and at an incident angle of 30–40°, with reflectance peak maxima positioned at ~ 412 nm and 478 nm. Additionally, the forewing scale of this butterfly acts as an anti-reflection filter (< 460 nm) for p-polarized light, showing greater polarization anisotropy in the lower wavelength region. Numerical simulationand microstructure-based analytical calculations with blaze angle grating effects have been considered to elucidate the observed dark-blue iridescence at large. Moreover, both the forewing and hindwing of the butterfly exhibit the ‘lotus effect’, with a contact angle as high as of ~ 150°, low contact angle hysteresis (16° and 13°) as well as low roll-off angles (10° and 7°) to favor self-cleaning action. Theoretical calculations attributing to dual roughnesses would encompass micro-textured and nanoscale asperities within the wing scale interface. The scope of the bifunctional features including optical and dewetting responses in natural systems would provide valuable insights and clues for biomimetics, particularly in nanophotonic and nanocoating applications.
Interaction of an electron and a uniformly charged spherical donor impurity
Authors: Mandal S , Karakoç M , Bayrak O
Published: April 2024

In this study, we propose an interaction potential between an electron and a uniformly charged spherical donor impurity in a quantum dot and numerically solve the Schrödinger equation using the finite difference method. We investigate the effects of the potential depth, donor radius, temperature, and hydrostatic pressure on the electronic and optical properties of an electron-donor impurity in a quantum dot, including absorption coefficients and the total change in the relative refractive index during the transition of an electron from the ground (1s) to excited (2p) states in the conduction band. Our findings indicate that an increase in donor radius or temperature leads to a red shift in the optical response, holding the parameters constant. Conversely, an increase in potential depth or hydrostatic pressure induces a blue shift in the optical response under the constant parameters.
Decomposition solutions and Bäcklund transformations of the B-type and C-type Kadomtsev–Petviashvili equations
Authors: Hao Xiazhi , Lou S Y
Published: April 2024

This paper introduces a modified formal variable separation approach, showcasing a systematic and notably straightforward methodology for analyzing the B-type Kadomtsev–Petviashvili (BKP) equation. Through the application of this approach, we successfully ascertain decomposition solutions, Bäcklund transformations, the Lax pair, and the linear superposition solution associated with the aforementioned equation. Furthermore, we expand the utilization of this technique to the C-type Kadomtsev–Petviashvili (CKP) equation, leading to the derivation of decomposition solutions, Bäcklund transformations, and the Lax pair specific to this equation. The results obtained not only underscore the efficacy of the proposed approach, but also highlight its potential in offering a profound comprehension of integrable behaviors in nonlinear systems. Moreover, this approach demonstrates an efficient framework for establishing interrelations between diverse systems.
The impact of segment dilution on the magnetic and hysteretic properties of ferrimagnetic (1/2-1) segmented Ising nanowire
Authors: Kantar Ersin
Published: April 2024

This study explores the presence of diverse phase diagrams and hysteresis characteristics, as well as their dependencies on segment dilution, in an Ising-type core/shell segmented nanostructure. The magnetic and hysteretic behavior of the nanostructure was carefully investigated by employing the effective-field theory and its respective diluted parameters. The phase diagrams reveal characteristic phenomena that are influenced by the dilution parameters. Specifically, this study examined the variations in phase transitions and tricritical points by altering the dilution and physical parameters of the segments. The investigation also encompasses an examination of the hysteresis characteristics, including the hysteresis loop, coercivity, and remanence, in relation to the segment dilution dependence of the segmented nanowire. It was discovered that as the temperature rises, the hysteresis loop areas diminish. However, intriguingly, at specific dilution and crystal area values, the hysteresis loop areas exhibit an augmentation.
Metamaterial terahertz device with temperature regulation function that can achieve perfect absorption and complete reflection conversion of ultrawideband
Authors: Sun Hao , Yi Zao , Ma Can , Cheng Shubo , Tang Bin , Zeng Qingdong , Ahmad Sohail
Published: April 2024

The field of terahertz devices is important in terahertz technology. However, most of the current devices have limited functionality and poor performance. To improve device performance and achieve multifunctionality, we designed a terahertz device based on a combination of VO2 and metamaterials. This device can be tuned using the phase-transition characteristics of VO2, which is included in the triple-layer structure of the device, along with SiO2 and Au. The terahertz device exhibits various advantageous features, including broadband coverage, high absorption capability, dynamic tunability, simple structural design, polarization insensitivity, and incident-angle insensitivity. The simulation results showed that by controlling the temperature, the terahertz device achieved a thermal modulation range of spectral absorption from 0 to 0.99. At 313 K, the device exhibited complete reflection of terahertz waves. As the temperature increased, the absorption rate also increased. When the temperature reached 353 K, the device absorption rate exceeded 97.7% in the range of 5–8.55 THz. This study used the effective medium theory to elucidate the correlation between conductivity and temperature during the phase transition of VO2. Simultaneously, the variation in device performance was further elucidated by analyzing and depicting the intensity distribution of the electric field on the device surface at different temperatures. Furthermore, the impact of various structural parameters on device performance was examined, offering valuable insights and suggestions for selecting suitable parameter values in real-world applications. These characteristics render the device highly promising for applications in stealth technology, energy harvesting, modulation, and other related fields, thus showcasing its significant potential.
On the spreading behavior of a droplet on a circular cylinder using the lattice Boltzmann method
Authors: Yang 杨 Fan 帆 , Jin 金 Hu 虎 , Dai 戴 Mengyao 梦瑶
Published: April 2024

The study of a droplet spreading on a circular cylinder under gravity was carried out using the pseudo-potential lattice Boltzmann high-density ratios multiphase model with a non-ideal Peng–Robinson equation of state. The calculation results indicate that the motion of the droplet on the cylinder can be divided into three stages: spreading, sliding, and aggregating. The contact length and contact time of a droplet on a cylindrical surface can be affected by factors such as the wettability gradient of the cylindrical wall, the Bond number, and droplet size. Furthermore, phase diagrams showing the relationship between Bond number, cylinder wall wettability gradient, and contact time as well as maximum contact length for three different droplet sizes are given. A theoretical foundation for additional research into the heat and mass transfer process between the droplet and the cylinder can be established by comprehending the variable rules of maximum contact length and contact time.
Bifurcation analysis and control study of improved full-speed differential model in connected vehicle environment
Authors: Ai 艾 Wen-Huan 文欢 , Lei 雷 Zheng-Qing 正清 , Li 李 Dan-Yang 丹洋 , Fang 方 Dong-Liang 栋梁 , Liu 刘 Da-Wei 大为
Published: April 2024

In recent years, the traffic congestion problem has become more and more serious, and the research on traffic system control has become a new hot spot. Studying the bifurcation characteristics of traffic flow systems and designing control schemes for unstable pivots can alleviate the traffic congestion problem from a new perspective. In this work, the full-speed differential model considering the vehicle network environment is improved in order to adjust the traffic flow from the perspective of bifurcation control, the existence conditions of Hopf bifurcation and saddle-node bifurcation in the model are proved theoretically, and the stability mutation point for the stability of the transportation system is found. For the unstable bifurcation point, a nonlinear system feedback controller is designed by using Chebyshev polynomial approximation and stochastic feedback control method. The advancement, postponement, and elimination of Hopf bifurcation are achieved without changing the system equilibrium point, and the mutation behavior of the transportation system is controlled so as to alleviate the traffic congestion. The changes in the stability of complex traffic systems are explained through the bifurcation analysis, which can better capture the characteristics of the traffic flow. By adjusting the control parameters in the feedback controllers, the influence of the boundary conditions on the stability of the traffic system is adequately described, and the effects of the unstable focuses and saddle points on the system are suppressed to slow down the traffic flow. In addition, the unstable bifurcation points can be eliminated and the Hopf bifurcation can be controlled to advance, delay, and disappear, so as to realize the control of the stability behavior of the traffic system, which can help to alleviate the traffic congestion and describe the actual traffic phenomena as well.
Improvement and security analysis of multi-ring discrete modulation continuous variable quantum secret sharing scheme
Authors: Jiang 姜 Huan-Yao 欢窈 , Nie 聂 Min 敏 , Yang 杨 Guang 光 , Sun 孙 Ai-Jing 爱晶 , Zhang 张 Mei-Ling 美玲 , Pei 裴 Chang-Xing 昌幸
Published: April 2024

In order to avoid the complexity of Gaussian modulation and the problem that the traditional point-to-point communication DM-CVQKD protocol cannot meet the demand for multi-user key sharing at the same time, we propose a multi-ring discrete modulation continuous variable quantum key sharing scheme (MR-DM-CVQSS). In this paper, we primarily compare single-ring and multi-ring M-symbol amplitude and phase-shift keying modulations. We analyze their asymptotic key rates against collective attacks and consider the security key rates under finite-size effects. Leveraging the characteristics of discrete modulation, we improve the quantum secret sharing scheme. Non-dealer participants only require simple phase shifters to complete quantum secret sharing. We also provide the general design of the MR-DM-CVQSS protocol. We conduct a comprehensive analysis of the improved protocol’s performance, confirming that the enhancement through multi-ring M-PSK allows for longer-distance quantum key distribution. Additionally, it reduces the deployment complexity of the system, thereby increasing the practical value.
Single event effects evaluation on convolution neural network in Xilinx 28 nm system on chip
Authors: Zhao 赵 Xu 旭 , Du 杜 Xuecheng 雪成 , Xiong 熊 Xu 旭 , Ma 马 Chao 超 , Yang 杨 Weitao 卫涛 , Zheng 郑 Bo 波 , Zhou 周 Chao 超
Published: April 2024

Convolutional neural networks (CNNs) exhibit excellent performance in the areas of image recognition and object detection, which can enhance the intelligence level of spacecraft. However, in aerospace, energetic particles, such as heavy ions, protons, and alpha particles, can induce single event effects (SEEs) that lead CNNs to malfunction and can significantly impact the reliability of a CNN system. In this paper, the MNIST CNN system was constructed based on a 28 nm system-on-chip (SoC), and then an alpha particle irradiation experiment and fault injection were applied to evaluate the SEE of the CNN system. Various types of soft errors in the CNN system have been detected, and the SEE cross sections have been calculated. Furthermore, the mechanisms behind some soft errors have been explained. This research will provide technical support for the design of radiation-resistant artificial intelligence chips.
Influence of temperature, stress, and grain size on behavior of nano-polycrystalline niobium
Authors: Yan 晏 Yu-Ping 玉平 , Zhang 张 Liu-Ting 柳亭 , zhang 张 Li-Pan 丽攀 , Lu 芦 Gang 刚 , Tu 涂 Zhi-Xin 志新
Published: April 2024

Atomic simulations are executed to investigate the creep responses of nano-polycrystalline (NC) niobium established by using the Voronoi algorithm. The effects of varying temperature, applied stress, and grain size (GS) on creep properties and mechanisms are investigated. Notably, the occurrence of tertiary creep is exclusively observed under conditions where the applied stress exceeds 4.5 GPa and the temperature is higher than 1100 K. This phenomenon can be attributed to the significant acceleration of grain boundary and lattice diffusion, driven by the elevated temperature and stress levels. It is found that the strain rate increases with both temperature and stress increasing. However, an interesting trend is observed in which the strain rate decreases as the grain size increases. The stress and temperature are crucial parameters governing the creep behavior. As these factors intensify, the creep mechanism undergoes a sequential transformation: initially from lattice diffusion under low stress and temperature conditions to a mixed mode combining grain boundaries (GBs) and lattice diffusion at moderate stress and mid temperature levels, and ultimately leading to the failure of power-law controlled creep behavior, inclusive of grain boundary recrystallization under high stress and temperature conditions. This comprehensive analysis provides in more detail an understanding of the intricate creep behavior of nano-polycrystalline niobium and its dependence on various physical parameters.
Opinion consensus incorporating higher-order interactions in individual-collective networks
Authors: Ye 叶 Shun 顺 , Tu 涂 Li-Lan 俐兰 , Wang 王 Xian-Jia 先甲 , Hu 胡 Jia 佳 , Wang 王 Yi-Chao 薏潮
Published: April 2024

In the current information society, the dissemination mechanisms and evolution laws of individual or collective opinions and their behaviors are the research hot topics in the field of opinion dynamics. First, in this paper, a two-layer network consisting of an individual-opinion layer and a collective-opinion layer is constructed, and a dissemination model of opinions incorporating higher-order interactions (i.e. OIHOI dissemination model) is proposed. Furthermore, the dynamic equations of opinion dissemination for both individuals and groups are presented. Using Lyapunov’s first method, two equilibrium points, including the negative consensus point and positive consensus point, and the dynamic equations obtained for opinion dissemination, are analyzed theoretically. In addition, for individual opinions and collective opinions, some conditions for reaching negative consensus and positive consensus as well as the theoretical expression for the dissemination threshold are put forward. Numerical simulations are carried to verify the feasibility and effectiveness of the proposed theoretical results, as well as the influence of the intra-structure, inter-connections, and higher-order interactions on the dissemination and evolution of individual opinions. The main results are as follows. (i) When the intra-structure of the collective-opinion layer meets certain characteristics, then a negative or positive consensus is easier to reach for individuals. (ii) Both negative consensus and positive consensus perform best in mixed type of inter-connections in the two-layer network. (iii) Higher-order interactions can quickly eliminate differences in individual opinions, thereby enabling individuals to reach consensus faster.
Multi-functional photonic spin Hall effect sensor controlled by phase transition
Authors: Cheng 程 Jie 杰 , Li 李 Rui-Zhao 瑞昭 , Cheng 程 Cheng 骋 , Zhang 张 Ya-Lin 亚林 , Liu 刘 Sheng-Li 胜利 , Dong 董 Peng 鹏
Published: April 2024

Photonic spin Hall effect (PSHE), as a novel physical effect in light–matter interaction, provides an effective metrological method for characterizing the tiny variation in refractive index (RI). In this work, we propose a multi-functional PSHE sensor based on VO2, a material that can reveal the phase transition behavior. By applying thermal control, the mutual transformation into different phase states of VO2 can be realized, which contributes to the flexible switching between multiple RI sensing tasks. When VO2 is insulating, the ultrasensitive detection of glucose concentrations in human blood is achieved. When VO2 is in a mixed phase, the structure can be designed to distinguish between the normal cells and cancer cells through no-label and real-time monitoring. When VO2 is metallic, the proposed PSHE sensor can act as an RI indicator for gas analytes. Compared with other multi-functional sensing devices with the complex structures, our design consists of only one analyte and two VO2 layers, which is very simple and elegant. Therefore, the proposed VO2-based PSHE sensor has outstanding advantages such as small size, high sensitivity, no-label, and real-time detection, providing a new approach for investigating tunable multi-functional sensors.
Effects of asymmetric coupling and boundary on the dynamic behaviors of a random nearest neighbor coupled system
Authors: Xu 徐 Ling 玲 , Jiang 姜 Lei 磊
Published: April 2024

This study investigates the dynamical behaviors of nearest neighbor asymmetric coupled systems in a confined space. First, the study derivative analytical stability and synchronization conditions for the asymmetrically coupled system in an unconfined space, which are then validated through numerical simulations. Simulation results show that asymmetric coupling has a significant impact on synchronization conditions. Moreover, it is observed that irrespective of whether the system is confined, an increase in coupling asymmetry leads to a hastened synchronization pace. Additionally, the study examines the effects of boundaries on the system’s collective behaviors via numerical experiments. The presence of boundaries ensures the system’s stability and synchronization, and reducing these boundaries can expedite the synchronization process and amplify its effects. Finally, the study reveals that the system’s output amplitude exhibits stochastic resonance as the confined boundary size increases.
A pressure-sensitive rheological origin of high friction angles of granular matter observed in NASA–MGM project
Authors: Cheng 程 Xiaohui 晓辉 , Xiao 肖 Shize 世泽 , Yang 杨 Sen 森 , Zhao 赵 Naifeng 乃峰 , Cao Alex Sixie
Published: April 2024

An abnormally high peak friction angle of Ottawa sand was observed in (National Aeronautics and Space Administration) NASA–(Mechanics of Granular Materials) MGM tests in microgravity conditions on the space shuttle. Previous investigations have been unsuccessful in providing a constitutive insight into this behavior of granular materials under extremely low effective stress conditions. Here, a recently proposed unified constitutive model for transient rheological behavior of sand and other granular materials is adopted for the analytical assessment of high peak friction angles. For the first time, this long-eluded behavior of sand is attributed to a hidden rheological transition mechanism, that is not only rate-sensitive, but also pressure-sensitive. The NASA–MGM microgravity conditions show that shear-tests of sand can be performed under abnormally low confining stress conditions. The pressure-sensitive behavior of granular shearing that is previously ignored is studied based on the μ(I) rheology and its variations. Comparisons between the model and the NASA microgravity tests demonstrate a high degree of agreement. The research is highly valid for pressure-sensitive and rate-dependent problems that occur during earthquakes, landslides, and space exploration.
Field induced Chern insulating states in twisted monolayer–bilayer graphene
Authors: Wang 王 Zhengwen 政文 , Han 韩 Yingzhuo 英卓 , Watanabe Kenji , Taniguchi Takashi , Jiang 姜 Yuhang 宇航 , Mao 毛 Jinhai 金海
Published: April 2024

Unraveling the mechanism underlying topological phases, notably the Chern insulators (ChIs) in strong correlated systems at the microscopy scale, has captivated significant research interest. Nonetheless, ChIs harboring topological information have not always manifested themselves, owing to the constraints imposed by displacement fields in certain experimental configurations. In this study, we employ density-tuned scanning tunneling microscopy (DT-STM) to investigate the ChIs in twisted monolayer–bilayer graphene (tMBG). At zero magnetic field, we observe correlated metallic states. While under a magnetic field, a metal–insulator transition happens and an integer ChI is formed emanating from the filling index s = 3 with a Chern number C = 1. Our results underscore the pivotal role of magnetic fields as a powerful probe for elucidating topological phases in twisted Van der Waals heterostructures.
Numerical simulation of early-age thermal stress of high volume fly ash (HVFA) concrete
Authors: Xin Jianda , Li Zhi , Zhang Guoxin , Liu Yi , Zhang Lei , Zhu Jingping , Liu Longlong , Rong Muning
Published: April 2024

This paper numerically studied the effect of fly ash (FA) replacement on early-age thermal stress of concrete. Different FA replacement levels (0%, 20%, 50% and 80%) on the thermal stress and cracking risk of concrete have been considered. Results showed that, due to the FA effect on the reduction of hydration heat, the maximum temperature and corresponding compressive stress during the temperature rise stage were both lowered; meanwhile, the strength of concrete was simultaneously weakened, leading to lower cracking stress when the FA replacement increased gradually. Finally, the cracking temperature of concrete decreased when the FA replacement level increased up to 50%, and converted to plateau with higher FA replacement level. Overall, FA replacement level with 50% was recommended for concrete under restraint cracking risk.
Numerical Study on the Efficiency of the Point Smoke Exhaust System in V-shaped Urban Underground Road Tunnel
Authors: Kang Siyan , Li Junmei , Qiao Yaxin , Qi Zhao , Lu Huimin , Ouyang Li
Published: April 2024

In order to study the exhaust effect of the point smoke exhaust system in V-shaped urban underground tunnel with different structures, effects of the slope differences on both sides of the slope changing point and the operating mode of the exhaust vent on the smoke spread distance, temperature at the height of 2 m above the road and the ceiling temperature were studied by the numerical method. The research results show that for the symmetric V-shaped tunnel, smoke can be controlled in the required range, but for asymmetric V-shaped tunnel with the slope difference on both sides, smoke cannot be easily controlled, ventilation supply is needed to improve the smoke exhaust efficiency. Point smoke exhaust system cannot effectively reduce the maximum temperature of the ceiling above the fire. When the fire source power is large, for the symmetrical V-shaped tunnel with a small slope, some fire prevention measures must be taken to protect the ceiling partition. For the asymmetric V-shaped tunnel, two exhaust vents opened on the small slope side and four opened on the large slope side are suggested for the occupant safe evacuation in tunnel.
Research on less temperature flawing resistance of steel residue asphalt composition based on SCB test
Authors: Wang Hongwei , Feng Xuemao , Liu Jiaqing , Wu Jianmin , Jiao Xiaodong , Shu Zhiqiang
Published: April 2024

In view of the increasing application of steel residue in asphalt pavement construction in China, in order to analyze the less temperature flawing resistance of steel residue asphalt composition, the less temperature semi-circular bending test (SCB) was used to analyze the less temperature flawing resistance of steel residue asphalt composition (SSAC-13) with various residue content based on the stress peak value and stress attenuation, rupture toughness, rupture energy and critical rupture energy density. The results show that the content of steel residue has a noticeable influence on the less temperature flawing resistance of steel residue asphalt composition. Considering the less temperature flawing resistance, the recommended steel residue content is 40%.
Effect of tempering on corrosion properties of mold steel
Authors: Cheng Xueming , Cheng Lei , Niu Ben , Qiu Yunjun , Zhu Guojian , Liu Chengzhe
Published: April 2024

There are many strongly developed karsts in South China, which bring great uncertainty to the construction stability of underground projects. This paper takes the deep foundation pit project of a station in a sandy soil area as the background, simulates the deep foundation pit excavation process based on finite element software, and comparatively analyzes the influence of the existence of karst holes on the foundation pit support structure. The results show that the effective treatment of solution holes in the process of foundation pit excavation can reduce the risk of surface settlement around the foundation pit but has less influence on the lateral displacement of the foundation pit support structure. The cavity grouting reinforcement technology is also introduced in detail in the paper, which can provide a reference for the reinforcement of deep foundation pit projects in sandy soil stratum containing strong development of large cavities.
Study on interpretation of Marine Geotechnical parameter based on static sounding
Authors: Zhang Ying , Di ShengJie , Zhou Heng , Mu Qingyi , Hu Xiangyang , Jing Liu
Published: April 2024

In recent years, the rapid rise of offshore wind power. Compared with other Marine exploration means and methods, pore pressure static penetration test is more economical, more efficient and more reliable. It has been widely used and is an indispensable exploration means in offshore wind power projects. Based on the survey results of the offshore windpower project in Guangdong in recent years, the applicability of using the pore pressure static sounding (CPTU) empirical formula to interpret various geotechnical parameters of offshore projects is analyzed in this paper, which can provide experience and reference for similar offshore projects.
Study on Improved Large Span Propping System for Reinforced Concrete Composite Slabs with Lattice Girders
Authors: Li Siyao , Li Liming , Shi Pengfei , Guo Zhipeng , Su Yanjiang , Li Yubo
Published: April 2024

To further improve the installation efficiency of commonly used reinforced concrete composite slabs with lattice girders in China, an Improved Large Span Propping System is proposed. This article investigates the mechanical properties of the new propping system through in-situ monitoring. The monitoring results show that the displacement and stress of the prefabricated layer can meet the requirements of current Chinese standards, which indicates the feasibility of the new support system. Compared with the original Large Span Propping System, the new propping system can further utilize the bending stiffness of the prefabricated layer and reduce the installation amount of the lower propping frame.
The Development of New Type GFRP Hollow Panels
Authors: Wei Yuxin , Wang Zhiping , Xiang Junzheng , Qiang Sheng
Published: April 2024

Under the background of global energy transformation, pumped storage power stations are becoming more and more important. Most of their water retaining structures adopt face rockfill dams, but their concrete panels will have many problems such as durability. In this study, a new type of GFRP hollow panel was developed for face rockfill dam. The nonlinear behavior and damage process of the material were simulated by finite element analysis and UMAT subroutine. Through analysis and comparison, it is found that the triangular section form is superior to other forms in terms of stress distribution and bearing capacity. After optimization design, the optimal section takes into account the stability, safety and economic benefits of the structure. The research results provide a high-performance panel solution with high construction efficiency and low maintenance cost for the face rockfill dam, and provide an important design reference for the application of GFRP composite materials in water conservancy projects in the future.
Impact Analysis of Section Seismic Capacity in Potential Plastic Hinge Zone of Engineered Cementitious Composite Based on OpenSees
Authors: Yuan Jiaquan , Jiang Weihong , Feng Luyang , Duan Wenhong , Li Huimei , Hu Guiling , Moulin  , Xu Weibing , Huang Xiaomin , Yang Kun
Published: April 2024

In this paper, OpenSees is used to analyze the moment-curvature (M-φ) curves of the bottom cross section of 4×40m continuous girder piers under the same reinforcing conditions, which are completely made of C40 concrete, partially made of Engineered Cementitious Composite material concrete(ECC) outsourced concrete, and completely made of ECC concrete, and then evaluate its seismic performance. Meanwhile, the yield curvature and ultimate curvature changes of the abutment section under different axial compression ratios are investigated. The results show that the yield curvature and ultimate curvature of ECC are larger than those of ordinary concrete, and the deformation capacity of ECC is stronger under the same axial force. The results also show that the yield moment and yield curvature of the section gradually increase with the increase of axial compression ratio, and the curvature ductility of the section deteriorates.
Influence of foundation pit excavation on the internal force of adjacent shield segment structure
Authors: Jiang Y.X. , Wang M. , Feng S. , Li Y.D. , Wang H.L. , Ran L. , Jin T.
Published: April 2024

As subway line density increases, excavation of foundation pits around tunnels unavoidably triggers soil disturbance. This consequently alters the on-site strain and distortion fields of the soil, resulting in internal force modifications in the tunnel shield segment and joint failure. To maintain tunnelling structure safety through numerous foundation pit diggings, this study uses a real-world project as its model. Leveraging the tunnel convergent deformation results derived from prior analyses with PLAXIS 3D software, the Midas GTS software is utilized to explore the alterations in internal forces and joint failure patterns of the tunnel subjected to convergent deformations of 4cm and 5cm. The findings are as follows: (i) Under the effect of a vertical load, the segment deformation takes on a transverse elliptical shape. (ii) The majority of joint failure is primarily focused around the foundation pit excavation area, where the base of the arch opens inwardly, and the midsection of the arch expands outwardly. (iii) The stress on the structure escalates as the extent of foundation pit excavation increases.
A note on new weighted geometric inequalities for hypersurfaces in ℝⁿ
Authors: Wu Jie
Published: April 2024

In this note, we prove a family of sharp weighed inequalities which involve weighted

k
k

-th mean curvature integral and two distinct quermassintegrals for closed hypersurfaces in

R

n

\mathbb {R}^n

. This inequality generalizes the corresponding result of Wei and Zhou [Bull. Lond. Math. Soc. 55 (2023), pp. 263–281] where their proof is based on earlier results of Kwong-Miao [Pacific J. Math. 267 (2014), pp. 417–422; Commun. Contemp. Math. 17 (2015), p. 1550014]. Here we present a proof which does not rely on Kwong-Miao’s results.
Association between ACE1 and missed abortion: ACE1 promotes H2O2-induced trophoblast cell injury in vitro
Authors: Yan Yi-dan , Ji Wen-xia , Zhao Na , Zhang Jian-juan , Du Jie , Lu Ting , Gu Wei-qun
Published: April 2024

The aim of this study was to evaluate the role of angiotensin-converting enzyme 1 (ACE1) in H2O2-induced trophoblast cell injury and the potential molecular mechanisms. Oxidative stress was modeled by exposing HTR-8/SVneo cells to 200 μM H2O2. Western blot and real-time quantitative PCR methods were used to detect protein and mRNA expression level of ACE1 in chorionic villus tissue and trophoblast HTR-8/SVneo cell. Inhibition of ACE1 expression was achieved by transfection with small interfering RNA. Then flow cytometry, Cell Counting Kit-8, and Transwell assay was used to assess apoptosis, viability, and migration ability of the cells. Reactive oxygen species (ROS) were detected by fluorescent probes, and malondialdehyde (MDA), superoxide dismutase (SOD), and reduced glutathione (GSH) activities were determined by corresponding detection kits. Angiotensin-converting enzyme 1 expression was upregulated in chorionic villus tissue of patients with missed abortion (MA) compared with individuals with normal early pregnancy abortion. H2O2 induced elevated ACE1 expression in HTR-8/SVneo cells, promoted apoptosis, and inhibited cell viability and migration. Knockdown of ACE1 expression inhibited H2O2-induced effects to enhance cell viability and migration and suppress apoptosis. Additionally, H2O2 stimulation caused increased levels of ROS and MDA and decreased SOD and GSH activity in the cells, whereas knockdown of ACE1 expression led to opposite changes of these oxidative stress indicators. Moreover, knockdown of ACE1 attenuated the inhibitory effect of H2O2 on the Nrf2/HO-1 pathway. Angiotensin-converting enzyme 1 was associated with MA, and it promoted H2O2-induced injury of trophoblast cells through inhibiting the Nrf2 pathway. Therefore, ACE1 may serve as a potential therapeutic target for MA.
Brittle bonds: queer relationalities in literary and cinematic forms in India
Authors: Mokkil Navaneetha
Published: April 2024

From factories to hostels, homes to neighbourhoods, how do embodied practices in stratified spaces shape the contemporary terrains of queerness in India? In this article, I analyse two recent cultural texts from India, Neeraj Ghaywan’s Geeli Pucchi (Sloppy Kisses, 2021) and Hansda Sowvender Shekhar’s (2018) novel My Father’s Garden, Speaking Tiger Books, Delhi, to engage with the fraught dynamics of relationality and queerness. My analysis contests any easy celebration of community – by foregrounding the movements of dispossessed protagonists who do not fit into the paradigm of the privileged subject of queer politics. Yet these texts capture the fleeting possibilities of reaching towards one another in spaces carved through the operations of exclusion and discrimination. I bring together two texts in which the direct references to sexual identities formed via governmental or non-governmental networks are largely absent; rather, they ask fundamental questions about the in-between terrain of the relational. The dynamics of distance and connection is opened up in complex ways in these cinematic and literary texts as they create imaginative idioms to explore the brittleness of queer bonds formed through the hierarchized operations of class, caste and ethnicity. Through an analysis of the formal aspects of these texts, and the practices of spectatorship and readership they facilitate, I seek to underline how formations of sexuality in India can be unpacked only through a close engagement with the critical discourse on gender, caste and ethnicity.
Queerious communities: building writing centres in Indian universities
Authors: Dasgupta Anannya
Published: April 2024

This paper examines the new phenomenon of writing centres being made a part of universities, particularly the liberal arts private universities, in India, as growing in a way that lends it to consciously choosing queer pedagogy and to building it as a politically queer space. While some aspects of the queering of writing centres mirror the invisibilizing and the burden of proving the worth of their existence in the way queer communities are, other aspects build on what queer theory enables in terms of understanding what it takes to build communities where what is normative will continually shift what it excludes. Queer theory reminds us of the fluid and constantly reconstituting nature of identity formation whether it is based on non-binary gender identity or identities caught in the debilitating intersections of class, caste, religion, ability and sexuality. This has led to a recognition that communities formed around the learning of reading, writing and thinking, as writing centres are, are predisposed to shift focus from product to process as a move in the practice of teaching writing because it considers the individual reading-and-writing-selves present in the classroom as subjects-in-formation. This paper argues that writing pedagogy is creating queer communities because it invites and supports unsettled subjective selves to the process of knowledge production.
Cross-Domain Recommendation To Cold-Start Users Via Categorized Preference Transfer
Authors: Liu Xiaoyang , Fu Xiaoyang , De Meo Pasquale , Fiumara Giacomo
Published: April 2024

Most existing cross-domain recommendation (CDR) systems apply the embedding and mapping idea to tackle the cold-start user problem and, to this end, they learn a common bridge function to transfer the user preferences from the source domain into the target domain. However, sharing a bridge function for all users inevitably leads to biased recommendations. This paper proposes a novel method, named CDR to cold-start users via categorized preference transfer (CDRCPT), to overcome the shortcomings of existing approaches. First, the embeddings of users and items in both the source and target domain are learned through pretraining and we utilize preference encoder to obtain the preference embeddings of users in the source domain. Second, mini-batch clustering is applied in the source domain to group users according to their preferences; here, each cluster identifies a specific class of users, and each cluster is represented by its center. Finally, the general representation is fed into a meta network to learn a bridge function for each available class of users. Experiments on two real data sets show that our CDRCPT method is effective in improving the accuracy and robustness of recommendations.
Deep Learning Model for Tamil Part-of-Speech Tagging
Authors: Visuwalingam Hemakasiny , Sakuntharaj Ratnasingam , Alawatugoda Janaka , Ragel Roshan
Published: April 2024

Part-of-Speech (POS) tagging is one of the popular Natural Language Processing (NLP) tasks. It is also considered to be a preliminary task for other NLP applications such as speech recognition, machine translation, and sentiment analysis. A few works have been published on POS tagging for the Tamil language. However, the performance of the POS tagger with unknown words is not explored in the literature. The appearance of unknown words is a frequently occurring problem in POS tagging and makes it a challenging task. In this paper, we propose a deep learning-based POS tagger for Tamil using Bi-directional Long Short Term Memory (BLSTM). The performance of the POS tagger was evaluated using known and unknown words. The POS tagger with regular word-level embeddings produces 99.83 and 92.46% accuracies for all known and 63.21% unknown words. It clearly shows that the accuracy decreases when the number of unknown words increases. To improve the performance of the POS tagger with unknown words, the proposed BLSTM model that uses word-level, character-level and pre-trained word embeddings. Test results of this model show a 2.57% improvement for 63.21% of unknown words, with an accuracy of 95.03%.