A Comparison Of Beamforming Characteristics In Isotropic And Composite Plate Structures For Use In Structural Health Monitoring,
2024
Embry-Riddle Aeronautical University
A Comparison Of Beamforming Characteristics In Isotropic And Composite Plate Structures For Use In Structural Health Monitoring, Sarah Ketchersid
Doctoral Dissertations and Master's Theses
Structural health monitoring in plate-like simple structures using phased array beamsteering of guided Lamb waves is useful in damage detection and evaluation efforts. Lamb waves can be effectively used for beamsteering using a linear array. The experimentation primarily focuses on beamsteering in the aluminum panel, which involves developing a simulation based on extracted data to visualize the dispersion of waves across the panel. By evaluating parameters such as slowness, velocity, and amplitude direction and variation for a specific metallic plate, the wavefront generated by a single wave source can be represented as a function of propagation angle and distance from …
Effect Of Fabrication Parameters On The Ferroelectricity Of Hafnium Zirconium Oxide Films: A Statistical Study,
2024
Air Force Institute of Technology
Effect Of Fabrication Parameters On The Ferroelectricity Of Hafnium Zirconium Oxide Films: A Statistical Study, Guillermo A. Salcedo, Ahmad E. Islam, Elizabeth Reichley, Michael Dietz, Christine M. Schubert Kabban, Kevin D. Leedy, Tyson C. Back, Weison Wang, Andrew Green, Timothy S. Wolfe, James M. Sattler
Faculty Publications
Ferroelectricity in hafnium zirconium oxide (Hf1−xZrxO2) and the factors that impact it have been a popular research topic since its discovery in 2011. Although the general trends are known, the interactions between fabrication parameters and their effect on the ferroelectricity of Hf1−xZrxO2 require further investigation. In this paper, we present a statistical study and a model that relates Zr concentration (x), film thickness (tf), and annealing temperature (Ta) with the remanent polarization (Pr) in tungsten (W)-capped Hf1−xZrxO2. …
Interfacial Magnetism And Anisotropy In Dirac And Weyl Semimetals,
2024
University of South Florida
Interfacial Magnetism And Anisotropy In Dirac And Weyl Semimetals, Noah Schulz
USF Tampa Graduate Theses and Dissertations
Semimetals have gained intense interest recently due to their exotic magnetic and electronic properties. One of the most widely studied semimetals is graphene, a Dirac semimetal. The utilization of graphene in devices and sensors requires interfacing it with other materials, which may induce potentially strong interfacial effects. Furthermore, graphene alone does not possess magnetic order. Studying the interfacial effects between graphene and magnetic materials is therefore of great importance in the application of graphene to meet modern technological needs. Furthermore, by understanding the fundamental interfacial physics between graphene and magnetic materials, new properties can be unlocked, broadening the possible applications …
Engineering Nanofibers: Laboratory Characterization, Microstructural Analysis, And Image Processing Insights,
2024
University of Nebraska at Omaha
Engineering Nanofibers: Laboratory Characterization, Microstructural Analysis, And Image Processing Insights, Sayed Ahmadreza Razian, Mohammad Arjomandi, Kaspars Maleckis
UNO Student Research and Creative Activity Fair
Polymer nanofibers have attracted high interest in a wide array of applications, including biomaterial scaffolding, textiles, sensors, reinforcement in composites, and filtration systems. Many of these applications combine nanofibers into non-woven fabrics for better properties and easier manipulation. The properties and performance of nanofiber-based fabrics are affected by various microstructure parameters, including fiber alignment, diameter, and gap sizes between the nanofibers. These structural parameters can be controlled by adjusting various process parameters during manufacturing process, but the exact process parameter-microstructure relationships vary depending on the polymer system and need to be studied individually. The goal of this study is to …
Machine Learning Prediction Of Photoluminescence In Mos2: Challenges In Data Acquisition And A Solution Via Improved Crystal Synthesis,
2024
Pepperdine University
Machine Learning Prediction Of Photoluminescence In Mos2: Challenges In Data Acquisition And A Solution Via Improved Crystal Synthesis, Ethan Swonger, John Mann, Jared Horstmann, Daniel Yang
Seaver College Research And Scholarly Achievement Symposium
Transition metal dichalcogenides (TMDCs) like molybdenum disulfide (MoS2) possess unique electronic and optical properties, making them promising materials for nanotechnology. Photoluminescence (PL) is a key indicator of MoS2 crystal quality. This study aimed to develop a machine-learning model capable of predicting the peak PL wavelength of single MoS2 crystals based on micrograph analysis. Our limited ability to consistently synthesize high-quality MoS2 crystals hampered our ability to create a large set of training data. The project focus shifted towards improving MoS2 crystal synthesis to generate improved training data. We implemented a novel approach utilizing low-pressure chemical vapor deposition (LPCVD) combined with …
La1-Xsrxcoo3 Perovskite Nanomaterial: Synthesis, Characterization, And Its Biomedical Application,
2024
The University of Texas Rio Grande Valley
La1-Xsrxcoo3 Perovskite Nanomaterial: Synthesis, Characterization, And Its Biomedical Application, Adhira Tippur, Anyet Shohag, Luke Franco, Ahmed Touhami, Swati Mohan, Mohammed Uddin
Research Symposium
Early cancer detection is paramount for effective treatment and potential cures. This research explores the application of perovskite materials, specifically Sr2+-doped Lanthanum Cobaltite (La1-xSrxCoO3) nanomaterials, in cancer detection, with a focus on rats as an experimental model. The ferroelectric nature of these materials, synthesized through a combination of sol-gel and molten-salt processes, was examined at varying Sr2+ doping levels (1-20 wt%). Rigorous characterization, employing X-ray diffraction and scanning electron microscopy, confirmed the uniform morphology of nano cubes, laying the foundation for subsequent investigations. The magnetic properties of the perovskite nanoparticles were probed, suggesting their potential as a diagnostic tool for …
Study On Treatment Method Of Expansive Soil Embankment In Expressway Reconstruction And Extension,
2024
Anhui Transportation Holding Group Co .， Ltd.， Hefei ， Anhui 230088 ， China
Study On Treatment Method Of Expansive Soil Embankment In Expressway Reconstruction And Extension, Wang Yuwei, Hu Yanli, Zhang Rui
Journal of China & Foreign Highway
In order to fully utilize expansive soil as filler in highway reconstruction and expansion projects，this paper draws on the successful experience of using expansive soil directly in road construction.It proposes an embankment treatment scheme that involves the use of geogrid-reinforced expansive soil with edge wrapping，based on the reconstruction and expansion project of the Hefei to Dagudian section of the G 40 Shanghai-Shaanxi Expressway.Through laboratory tests，the road performance and swelling characteristics of the expansive soil filler were investigated to determine the applicable scope and compaction control indices of the filler.Then，the feasibility of the embankment treatment scheme was demonstrated through the prediction …
Research On Construction Risk Of Desert Highway Subgrade Engineering Based On Sem,
2024
School of Traffic and Transportation Engineering ，Changsha University of Science ＆Technology ，Changsha ， Hunan 410114 ，China
Research On Construction Risk Of Desert Highway Subgrade Engineering Based On Sem, Wang Shouxu, Han Lingyun
Journal of China & Foreign Highway
Highway construction in desert areas is of great significance to improving the nodes of transportation networks and developing the economy of remote areas.In order to effectively explore the construction risks of desert highway subgrade engineering，the five aspects of personnel risk，technical risk，material risk，mechanical risk，and environmental risk were analyzed，and 23 indicators affecting the construction risk of desert highway subgrade engineering were screened out by literature research method.Based on the effective data collected by questionnaire survey，a structural equation model （SEM ） of the construction risk of desert highway subgrade engineering was constructed，and the key influencing factors of the construction risk were analyzed.The results …
Lightweight Replacement Technology For Existing Soft Subgrade Based On Over‑Consolidated State,
2024
School of Marine Engineering Equipment ， Zhejiang Ocean University ， Zhoushan ， Zhejiang 316022 ， China ;School of Naval Architecture and Maritime ， Zhejiang Ocean University ， Zhoushan ， Zhejiang 316022 ， China
Lightweight Replacement Technology For Existing Soft Subgrade Based On Over‑Consolidated State, Huang Baotao, Zhang Mudan, Huang Xiangshuo, Fang Mingshan, Feng Jianxue, Huang Lizhen
Journal of China & Foreign Highway
In order to solve the differential settlement of soft subgrade in coastal areas，based on the elastic deformation theory of overconsolidation stress ratio，the calculation and analysis of artificial overconsolidation stress ratio and the new technology of lightweight replacement were carried out to reduce the additional stress of vehicle load and structure weigh.The results show that the replacement thickness of the lightweight material with suitable density can make the additional stress at the bottom of the subgrade less than the deadweight stress of the original soft soil，and the additional stress is less than the initial flow stress of the soft soil.The resulting …
Analysis Of Stress And Drainage Characteristics Of Water Film Between Tire And Road Surface And Influence Of Groove Parameters,
2024
Shandong Provincial Communications Planning and Design Institute Group Co .， Ltd.， Jinan ， Shandong 250101 ， China ;College of Civil and Transportation Engineering ， Hohai University ， Nanjing ， Jiangsu 210098 ， China
Analysis Of Stress And Drainage Characteristics Of Water Film Between Tire And Road Surface And Influence Of Groove Parameters, Sun Zhenhao, Chen Jun
Journal of China & Foreign Highway
In order to study the stress characterist ics of water film on cement concrete road surface under the action of the tire and the influence of grooves，the finite element model of tire-water film-road surface was constructed using SolidWorks and Ansys Workbench.Based on computational fluid dynamics （CFD ） control equation and fluid-structure coupling theory，the flow law of water film on road surface under the action of the tire and the influence of water film thickness，driving speed，groove width，groove spacing，and groove direction on the hydrodynamic lift of tire were analyzed.The results show that the hydrodynamic lift of the tire increases with the increasing …
Rut Development Law And Correction Factor Of Axle Load Conversion Of Asphalt Pavement In Long And Large Longitudinal Slope,
2024
School of Qilu Transportation ， Shandong University ， Jinan ， Shandong 250002 ， China
Rut Development Law And Correction Factor Of Axle Load Conversion Of Asphalt Pavement In Long And Large Longitudinal Slope, Guo Chenchen, Ding Tingting, Lyu Xin, Sun Jianxiu, Zhang Jizhe, Yao Zhanyong
Journal of China & Foreign Highway
The existing design specifications do not make special design provisions for pavements in long and large longitudinal slopes，and the directly applied design specifications ignore the stress characteristics of these pavements，which fail to guarantee pavement performance and life.In order to realize the differential design of the pavement structure of special road sections，based on the measured dynamic modulus of asphalt mixture，annual traffic volume，and temperature data，this paper used the self-developed temperature-axle load analysis software to convert the real traffic volume into standard axle load.Abaqus software was used to establish a rut model under the coupling effect of measured axle load and temperature，and the …
Mechanical Behavior Of Composite Structures Of Wearing Course And Underlying Layer For Asphalt Pavements,
2024
China Railway Construction Investment Group Corporation Limited ， Zhuhai ， Guangdong 519000 ， China
Mechanical Behavior Of Composite Structures Of Wearing Course And Underlying Layer For Asphalt Pavements, Yang Xiaohua, Yuan Zhanwen, Wen Yongbing, Zhou Chao, Wu Hao
Journal of China & Foreign Highway
The interlayer bonding state of pavement structures changes due to the influence of various factors under service conditions，and this change exhibits a significant influence on the mechanical behavior of pavement structures.Through the composite structure test and numerical analysis，the mechanical behavior of the composite structure of different wearing courses and underlying layers under different stresses and bonding states was studied.The test used three commonly used wearing course （surface layer ） materials of asphalt pavements，namely AC- 13，OGFC- 13，and SMA- 13 for comparative analysis.The test results show that different composite structures exhibit different interlayer bonding properties and fatigue characteristics due to the difference …
Shear Strength Test Of Hefei Expansive Soil Under Low Stress Conditions With Controlled Suction,
2024
School of Automotive and Transportation Engineering ， Hefei University of Technology ， Hefei ， Anhui 230009 ， China
Shear Strength Test Of Hefei Expansive Soil Under Low Stress Conditions With Controlled Suction, Hou Chaoqun, Zhang Rongjian, Li Yongxin
Journal of China & Foreign Highway
Topsoil slide and instability of expansive soil slopes may occur under variable saturation conditions.In order to study the strength characteristics of unsaturated expansive soil under low stress conditions，several different matrix suction and stress conditions were set by unsaturated triaxial apparatus.The triaxial shear test of Hefei expansive soil was carried out，and the test data were analyzed.The test results show that when the net confining stress on the expansive soil continues to weaken，the stress-strain curve transitions from strain hardening to strain softening.The strength of unsaturated expansive soil increases with increasing matrix suction.The shear strength of shallow expansive soil shows a significant reduction …
Comparative Analysis Of Test Results Of Different Nano‑Clay Improved Loess,
2024
School of Highway ， Chang'an University ， Xi'an ， Shaanxi 710064 ， China
Comparative Analysis Of Test Results Of Different Nano‑Clay Improved Loess, Zhao Danni, Cao Baohua, Xu Jiangbo, Nan Yalin, Chen Nengyuan, Zhang Peng, Wang Heping
Journal of China & Foreign Highway
The orthogonal design t est was used to quantitatively analyze the influencing factors and influence degree of compressive strength，shear strength index，and permeability coefficient of improved loess，and the optimal content of improved loess was obtained.In addition，the improvement mechanism of nano-clay materials on loess was explored by scanning electron microscopy.The results show that：① The factors affecting the compressive strength of improved loess are the content of nano-clay，water content，and curing age，and the factors affecting cohesion，internal friction angle，and permeability coefficient are the content，dry density，and confining pressure.② Under different influencing factors，nano-montmorillonite can effectively improve the compressive strength of loess than attapulgite.③ When the material content …
Influence Of Rap Content On Mechanical Properties And Pavement Performance Of Warm Recycled Asphalt Mixture,
2024
School of Transportation Engineering ， Shandong Jianzhu University ， Jinan ， Shandong 250101 ， China
Influence Of Rap Content On Mechanical Properties And Pavement Performance Of Warm Recycled Asphalt Mixture, Ren Ruibo, Yin Liyang, Xu Qiang, Zhao Pinhui, Ma Shidong
Journal of China & Foreign Highway
Warm recycling technology is an effective new technology for recycling recycled asphalt pavement （RAP ）.In order to improve the pavement performance of warm recycled asphalt and effectively enhance the recycling rate of RAP，the influence of RAP content on the performance of warm recycled asphalt mixture was investigated through mechanical properties and pavement performance analysis，and the correlation between dynamic stability and mechanical parameters of creep tests under repeated loading was discussed.The results show that with the increase in RAP content，the high-temperature stability，shear resistance，and elastic deformation resistance of warm recycled asphalt mixture are improved，but the low-temperature crack resistance and water stability are …
Different Forms Of Nano‑Sio2 In Emulsified Asphalt And Their Effects On Emulsion Storage Stability,
2024
Sixth Engineering Branch of CCCC Fourth Highway Engineering Co .， Ltd.， Tianjin 301700 ， China
Different Forms Of Nano‑Sio2 In Emulsified Asphalt And Their Effects On Emulsion Storage Stability, Ji Chao, Cao Yuanhao, Li Zhigang
Journal of China & Foreign Highway
The insufficient storage performance of emulsified asphalt has always been a problem affecting its application，and there have been studies in China on nano-SiO2 particles as additives to improve the stability of emulsified asphalt，but the effect is not obvious.Based on the principle of Pickering emulsion，nano-SiO2 with surface modification was used as an emulsifier to directly emulsify matrix asphalt，and whether its stability improvement effect on emulsified asphalt is better than nano-SiO2 as a modified additive was explored.Firstly，three emulsified asphalt were prepared，namely ordinary modified emulsified asphalt A，emulsified asphalt B with nano-SiO2 as a modified additive，and emulsified asphalt C based on the new nano-SiO2 …
Study On Test Methods Of Wheel Sticking‑Free Emulsified Asphalt,
2024
Research Institute of Highway Ministry of Transport ， Beijing 100088 ， China ;Key Laboratory of Transport Industry of Road Structure and Material ， Beijing 100088 ， China
Study On Test Methods Of Wheel Sticking‑Free Emulsified Asphalt, Wang Peng, Qin Yongchun, Wang Jie, Xiong Weiming, Chang Rong, Fu Chongfeng, Feng Guoli
Journal of China & Foreign Highway
The wheel sticking-free emulsified asphalt is a key material to solve the wheel sticking problem in the process of asphalt pavement construction，with the wheel sticking-free effect as the core index.The accurate evaluation of the wheel sticking-free effect is important for the popularization and application of wheel sticking-free emulsified asphalt.Based on the research results in China and abroad，two test methods for wheel sticking-free effects （counterweight method and indenter method ） were innovatively proposed，and the wheel sticking-free effects of various emulsified asphalt were evaluated.The test results show that the two test methods can accurately evaluate the wheel sticking-free performance of emulsified asphalt，and …
Study On Mobilization Rate Of Rap Aged Asphalt Based On Ftir,
2024
Jinhua Highway and Transportation Management Center ， Jinhua ， Zhejiang 321000 ， China
Study On Mobilization Rate Of Rap Aged Asphalt Based On Ftir, Zou Xiaoyong, Li Ning, Wu Wenxiu, Wang Xin, Xu Xiaohe
Journal of China & Foreign Highway
During the preparation of the recycled asphalt mixture，part of the aged asphalt is first transferred from the surface of the recycled material to the new aggregate and then diffused and fused with the new asphalt，in which the percentage of transferred aged asphalt plays a key role in the final regeneration effect.In order to study the degree of transfer of aged asphalt in reclaimed asphalt pavement （RAP ），the mobilization rate （RMR） was calculated and analyzed based on the Fourier transform infrared spectroscopy （FTIR ）.The AC-13 graded recycled asphalt mixture was mixed and sieved to separate the new aggregate and RAP.The recycled …
Effect Evaluation Method Of Foamed Asphalt Based On Digital Image Processing Technology,
2024
Shanxi Transportation Research Institute Group Co .， Ltd.， Taiyuan ， Shanxi 030000 ， China ;Shanxi Transportation Technology Research & Development Co .， Ltd.， Taiyuan ， Shanxi 030000 ， China
Effect Evaluation Method Of Foamed Asphalt Based On Digital Image Processing Technology, Chang Xiaoyu
Journal of China & Foreign Highway
In view of the shortage of deter mining the optimal foaming parameters of foamed asphalt only by experience，this paper adopted digital image processing technology to collect images of the mixture of foamed asphalt and milled material RAI obtained under different foaming conditions and carried out grayscale image conversion，morphological processing，binary image conversion，and image segmentation，so as to calculate the asphalt wrapping rate in different areas.With the uniform dispersion of asphalt in the mixture as the indicator，the foaming effect of foamed asphalt was evaluated，and the optimal foaming parameters were determined.The results show that the digital image processing technology can quickly and effectively evaluate …
Study On Flexural Behavior Of Wet Joints Of Prefabricated Steel‑Uhpc Composite Bridge Deck,
2024
Key Laboratory for Wind and Bridge Engineering of Hunan Province ， School of Civil Engineering ， Hunan University ， Changsha ， Hunan 410082 ， China
Study On Flexural Behavior Of Wet Joints Of Prefabricated Steel‑Uhpc Composite Bridge Deck, Liao Wancheng, Zhao Hua, An Jiahe
Journal of China & Foreign Highway
Prefabricated steel-UHPC composite bridge deck is a new deck structure system that places the longitudinal rib at the upper layer and forms PBL shear connectors.This structure can be prefabricated in the factory and assembled on-site.The adjacent steel beams are integrated by welding，and the cast in-situ UHPC wet joints connect the adjacent UHPC bridge decks.However，these wet joints represent the structure's vulnerable segments but with little research.To this end，a full-scale model test has been conducted to study the flexural behavior of the wet joints in a steel-UHPC composite bridge deck in a practical project.The Abaqus finite element model was established and verified …
