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Key Construction Technologies For Single-Tower Rotating-Cable Suspension Bridges With Steel Truss Girders In Mountainous Regions, Gao Shuangjian, Zhang Weichao, Fu Lihong, Zhu Shuo Jun 2026

Key Construction Technologies For Single-Tower Rotating-Cable Suspension Bridges With Steel Truss Girders In Mountainous Regions, Gao Shuangjian, Zhang Weichao, Fu Lihong, Zhu Shuo

Journal of China & Foreign Highway

Given the problems of narrow construction sites, difficult construction organization, and high safety and quality risks faced in the construction of bridges in steep canyon regions of mountainous areas, this paper carried out research on key technologies for bridge construction in mountainous areas based on the Yellow River Three Gorges Bridge of the Jiyuan‒Xin’an Expressway. For the excavation of deep and large anchorage foundation pits in mountainous areas, a technical scheme of “loosening controlled blasting combined mainly with mechanical excavation and supplemented by manual excavation” was adopted. As this project is a single-tower single-span ground-anchored rotating-cable suspension bridge, the technologies …

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Mix Proportion Design Of Tunnel Shotcrete Based On Diorite Manufactured Sand, Song Funing, Wang Zegang, Liu Naifei, Song Zhanping Jun 2026

Mix Proportion Design Of Tunnel Shotcrete Based On Diorite Manufactured Sand, Song Funing, Wang Zegang, Liu Naifei, Song Zhanping

Journal of China & Foreign Highway

Tunnel construction produces a large amount of waste slag, which cannot be effectively utilized due to various factors. By using tunnel slag to prepare manufactured sand to replace natural sand, resources can be saved; costs can be reduced, and the environment can be protected. Based on the Xi’an‒Shiyan high-speed railway project, the physical and mechanical properties of diorite along the tunnel were tested; the physical properties and concrete performance of manufactured sand and natural sand were comparatively studied, and the effects of water-binder ratio and sand ratio on the performance of shotcrete were analyzed by designing multiple sets of mix …

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Surface Deep Well Dewatering Methods For Tertiary Water-Rich Semi-Diagenetic Section Of Wangjiazhai Tunnel, Liu Chengwen, Liu Gang, Xu Hua, Wei Meng Jun 2026

Surface Deep Well Dewatering Methods For Tertiary Water-Rich Semi-Diagenetic Section Of Wangjiazhai Tunnel, Liu Chengwen, Liu Gang, Xu Hua, Wei Meng

Journal of China & Foreign Highway

The tertiary semi-diagenetic sandstone of the Wangjiazhai Tunnel on the Yunnan Linqing Expressway is characterized by loose structure, low diagenetic strength, and poor cementation. The geological disasters such as collapse, water gushing, and mud bursting are very easy to happen when the tunnel passes through the water-rich section. With the surface deep well dewatering of the tertiary water-rich semi-diagenetic section of Wangjiazhai Tunnel as an example, the surface deep well dewatering methods and key parameters for tunnel crossing the tertiary water-rich semi-diagenetic section were discussed. Based on the single well surface dewatering test, the groundwater level and strata permeability of …

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Ventilation Design And On-Site Effect Testing For Construction Of Multiple Working Faces In Tianshan Shengli Tunnel, Xiong Ziyi, Jia Haiyang, Suo Feiyu, Liu Weiwei, Chen Jianxun, Yang Ziyao, Wang Heqi Jun 2026

Ventilation Design And On-Site Effect Testing For Construction Of Multiple Working Faces In Tianshan Shengli Tunnel, Xiong Ziyi, Jia Haiyang, Suo Feiyu, Liu Weiwei, Chen Jianxun, Yang Ziyao, Wang Heqi

Journal of China & Foreign Highway

To explore the ventilation optimization and energy saving issues in the construction of multiple working faces in extra-long highway tunnels, the air volumes required for a single working face under drilling and blasting construction conditions and TBM tunneling conditions were determined respectively based on theoretical calculations. Combined with the tunnel construction organization scheme, two ventilation schemes were proposed, and they were compared and selected according to the configured power of axial fans. Based on the recommended scheme, the layout scheme of pollutant-discharging jet fans was designed, and its feasibility was finally verified by on-site measurements of pollutant concentrations. The research …

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A Prediction Method For Scale Of Karst Cave Water Inrush And Mud Outburst Based On Comprehensive Advanced Geological Prediction, Yang Weilin, Xiao Huabo, Meng Lubo, Zhang Caihong, Chen Weidong, Wang Hao Jun 2026

A Prediction Method For Scale Of Karst Cave Water Inrush And Mud Outburst Based On Comprehensive Advanced Geological Prediction, Yang Weilin, Xiao Huabo, Meng Lubo, Zhang Caihong, Chen Weidong, Wang Hao

Journal of China & Foreign Highway

To improve the accuracy of water inrush and mud outburst disaster prediction during tunnel construction through karst caves, a method of first forecasting the unfavorable geological conditions of karst caves and subsequently predicting water inrush and mud outburst geological disasters was proposed in this paper. First, a karst cave advanced prediction model based on the polynomial naive Bayes algorithm was established to predict the scale grade of karst caves. Secondly, taking the scale prediction results of karst caves as the input condition for water inrush and mud outburst, a support vector machine (SVM) grade prediction model for karst cave water …

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Research On Recognition Of Highway Toll Vehicles Based On Dual-View Feature Fusion Network, Xiao Qiang, Chen Xinjia, Chen Jing, Zhao Bin, Yan Kaifeng, Ding Hongwei Jun 2026

Research On Recognition Of Highway Toll Vehicles Based On Dual-View Feature Fusion Network, Xiao Qiang, Chen Xinjia, Chen Jing, Zhao Bin, Yan Kaifeng, Ding Hongwei

Journal of China & Foreign Highway

To solve the practical problems in vehicle type classification on toll roads, a deep learning network based on dual-view feature fusion, named ETCLNet, was proposed in this paper. A dual-branch architecture was adopted by the network to extract the features of vehicle head and side body images, respectively, and combined with an innovatively designed multi-scale feature extraction module, namely IPFE, and an adaptive weighting-based bilinear feature fusion (AWBF) mechanism, efficient and fine-grained vehicle feature representation was achieved. Through the design of parallel multi-scale convolutions and residual connections, the problem of gradient vanishing was effectively alleviated, and the adaptability to complex …

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Analysis Of Traffic Congestion Patterns In Continuous Bottleneck Construction Zones Of Highways Under Mixed Traffic Of Passenger And Freight Vehicles, Han Hailong, Song Tailong, Ma Tianyong, Fan Zhaodong, Chen Zhexin, Chen Liang Jun 2026

Analysis Of Traffic Congestion Patterns In Continuous Bottleneck Construction Zones Of Highways Under Mixed Traffic Of Passenger And Freight Vehicles, Han Hailong, Song Tailong, Ma Tianyong, Fan Zhaodong, Chen Zhexin, Chen Liang

Journal of China & Foreign Highway

To investigate the traffic congestion pattern changes in continuous bottleneck sections of highway construction zones under mixed passenger and freight traffic conditions, the spatio-temporal evolution laws of vehicle speed and lane-changing trajectory distribution in construction sections with successive lane-narrowing bottlenecks were studied. Based on measured highway data, traffic flow simulation parameters were calibrated using a genetic algorithm. By taking traffic volume and the proportion of passenger and freight vehicles as entry points, a traffic simulation experiment for continuous bottleneck construction zones under multi-factor coupling effects was constructed, and the spatio-temporal variation characteristics of speed and lane-changing trajectory distribution in the …

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Analysis Of Temperature Field Of Steel Box Girders During Steam Curing Construction Process Of Steel-Uhpc Composite Bridge Decks, Wu Shang, Zhang Yongjian Jun 2026

Analysis Of Temperature Field Of Steel Box Girders During Steam Curing Construction Process Of Steel-Uhpc Composite Bridge Decks, Wu Shang, Zhang Yongjian

Journal of China & Foreign Highway

To clarify the influence of high-temperature steam curing of steel-ultra-high performance concrete (UHPC) lightweight composite bridge deck paving on the temperature field of the steel box girder, taking a certain bridge in Hunan Province as an example, finite element numerical simulation and actual bridge testing were conducted on the temperature field of the steel box girder during the high-temperature steam curing process of the bridge deck paving. The numerical calculations were generally consistent with the test results. The analysis results indicate that under the superimposed effect of solar radiation heating and high-temperature steam curing heating, the maximum temperature of the …

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Road Design Methods For Brt Projects Based On French Standard System : A Case Study Of A Project In West Africa, Wang Meng, Wu Cheng Jun 2026

Road Design Methods For Brt Projects Based On French Standard System : A Case Study Of A Project In West Africa, Wang Meng, Wu Cheng

Journal of China & Foreign Highway

With the continuous advancement of China ’s “Belt and Road Initiative”, Chinese enterprises have become increasingly involved in international engineering markets, undertaking numerous transportation infrastructure projects, particularly in Africa and Southeast Asia. However, international engineering projects commonly face the challenge of inconsistent design standard systems across different countries, posing significant difficulties for Chinese enterprises during project implementation. To address this issue, the differences in BRT road design under Chinese and French standards were focused on in this study, and their respective design philosophies and methods were analyzed. Taking a BRT project in a West African country as an example, field …

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Material Point Method Simulation Of Soil Landslide Considering Interface Friction Effect, Zuo Zhipeng, Hu Shengliang, Li Maowen, Tong Chenxi, Li Haichao Jun 2026

Material Point Method Simulation Of Soil Landslide Considering Interface Friction Effect, Zuo Zhipeng, Hu Shengliang, Li Maowen, Tong Chenxi, Li Haichao

Journal of China & Foreign Highway

During the high-speed and long-runout sliding failure process of large landslides, severe friction and heat generation in the sliding zone induce an interface friction effect between the debris flow and the bedrock, influencing the final accumulation morphology of the landslide. In this paper, a two-dimensional landslide model of the Yangbaodi landslide in Shenzhen was established using the material point method. A contact algorithm was introduced through a multi-background grid method to conduct numerical simulations on the initiation, sliding, and accumulation processes of the landslide. The results show that after initiation, the landslide moves over a long distance in a flow-like …

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Stratified Multi-Well Pumping Tests And Back-Analysis Of Hydraulic Conductivity In Ultra-Deep Circular Foundation Pits, Luo Renkun, Wang Jie Jun 2026

Stratified Multi-Well Pumping Tests And Back-Analysis Of Hydraulic Conductivity In Ultra-Deep Circular Foundation Pits, Luo Renkun, Wang Jie

Journal of China & Foreign Highway

Dewatering prior to foundation pit excavation is a critical measure to prevent engineering hazards such as slope instability at the pit top, seepage around the pit, and bottom heave. As a key parameter in dewatering design, hydraulic conductivity directly influences the risk control in foundation pit engineering. Based on the east anchor foundation pit project of the Shiziyang Passageway, single-well pumping tests and stratified multi-well pumping tests were conducted. The water level variations in the internal dewatering wells and the external observation wells were monitored in stages. Accordingly, a finite difference numerical model for the pumping tests was established. The …

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Research On Mechanical Properties And Particle Breakage Of Construction Solid Waste Concrete Under Cyclic Loading, Li Xuejian, Song Yang, Dong Chenxi, Li Shengkai, Li Wangyuan Jun 2026

Research On Mechanical Properties And Particle Breakage Of Construction Solid Waste Concrete Under Cyclic Loading, Li Xuejian, Song Yang, Dong Chenxi, Li Shengkai, Li Wangyuan

Journal of China & Foreign Highway

To investigate the mechanical properties and particle breakage effect of construction solid waste, a series of static and dynamic direct shear tests were carried out using a dynamic interface shear tester. Different coarse particle contents (40%, 50%, and 60%), amplitudes (45 kPa, 60 kPa, and 75 kPa), and frequencies (0.5 Hz, 1 Hz, and 2 Hz) were used as variables, and the variation rules of shear stress‒shear displacement curves, shear strength parameters, and particle breakage under three normal stresses (50 kPa, 100 kPa, and 150 kPa) were analyzed. The results indicate that under the same initial normal stress, with the …

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Study On Mechanical Properties Of Ultra-High Performance Concrete With Granite Manufactured Sand After Heating And Cooling Treatment, Li Gang, Zhou Feilong, Lu Qiuju, Du Kun, Liu Kai Jun 2026

Study On Mechanical Properties Of Ultra-High Performance Concrete With Granite Manufactured Sand After Heating And Cooling Treatment, Li Gang, Zhou Feilong, Lu Qiuju, Du Kun, Liu Kai

Journal of China & Foreign Highway

Due to the frequent occurrence of building fires, the mechanical properties of concrete, as the most widely used construction material, are severely challenged under high temperatures. To explore the effect of granite manufactured sand content on the performance of ultra-high performance concrete (UHPC) after heating and cooling treatment, three types of UHPC specimens with different manufactured sand contents (0, 50%, and 100%) were prepared in this study. Then, the effects of manufactured sand content, heating temperature, and cooling regime on the P-wave velocity and uniaxial compressive strength of UHPC were obtained through experiments. The results indicate that the P-wave velocity …

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Characteristic Analysis Of Detection Profiles For Internal Moisture Content Of Asphalt Pavements Based On Ground Penetrating Radar, Yang Li, He Pingping, Liu Weizhen, Fu An Jun 2026

Characteristic Analysis Of Detection Profiles For Internal Moisture Content Of Asphalt Pavements Based On Ground Penetrating Radar, Yang Li, He Pingping, Liu Weizhen, Fu An

Journal of China & Foreign Highway

As a novel non-destructive testing method for roads, ground penetrating radar (GPR) can effectively prevent road water damage by regularly detecting the internal moisture condition of roads. However, when the moisture data of GPR are analyzed, the moisture conditions obtained by relying solely on the analysis of a single profile characteristic may be misjudged. To improve the accuracy and reliability of GPR in detecting the internal moisture content of pavements, focus was placed on the time-frequency domain analysis of GPR moisture content detection profiles in this paper. Simulation tests were conducted, and the influencing factors and results of moisture detection …

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Research On Mechanical Properties Of Concrete At High Temperatures Based On Machine Learning, Liu Junhua, Liu Bin, Cao Haifeng, Liu Zhiguang, Li Zhiyong Jun 2026

Research On Mechanical Properties Of Concrete At High Temperatures Based On Machine Learning, Liu Junhua, Liu Bin, Cao Haifeng, Liu Zhiguang, Li Zhiyong

Journal of China & Foreign Highway

Structural safety is directly affected by the mechanical properties of concrete at high temperatures. Firstly, based on the existing compression and tension test data of concrete at high temperatures, the Abaqus finite element software was adopted for numerical simulation reproduction, and the reliability of the simulation method was verified. Secondly, by simulating the uniaxial tension-compression and confining pressure tests of normal concrete with different strength grades under high temperatures of 20‒800 ℃, the influence rules of temperature on the compressive strength, splitting tensile strength, elastic modulus, and stress ‒ strain relationship of concrete were elucidated. Finally, based on three commonly …

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Research On Dic Monitoring Of Dynamic Deflection And Damage Identification Method For Small And Medium-Span Bridges, Wang Yong, Li Derui, Tang Haotian, Yan Xingfei, Cheng Bin Jun 2026

Research On Dic Monitoring Of Dynamic Deflection And Damage Identification Method For Small And Medium-Span Bridges, Wang Yong, Li Derui, Tang Haotian, Yan Xingfei, Cheng Bin

Journal of China & Foreign Highway

A large number of built small and medium-span bridges in China are facing the problem of increasingly degrading structural performance. Therefore, it is of great significance to carry out lightweight intelligent monitoring and realize damage identification and early warning, so as to ensure the safe operation of these bridges. For typical small and medium-span simply supported beam bridges, a damage analysis method based on measured dynamic deflection data was established by combining the influence line theory and mechanical constitutive equations. Furthermore, based on the high-precision monitoring algorithm and instruments of digital image correlation (DIC), the real-time dynamic deflection data of …

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Comparative Study On Pouring Timing Of Sealing Hinge Concrete For Concrete-Filled Steel Tube Arch Bridge, Wang Xiaoliang, Fu Kaige, Zhang Song, Wang Zhongqiang, Chen Zhuoyi Jun 2026

Comparative Study On Pouring Timing Of Sealing Hinge Concrete For Concrete-Filled Steel Tube Arch Bridge, Wang Xiaoliang, Fu Kaige, Zhang Song, Wang Zhongqiang, Chen Zhuoyi

Journal of China & Foreign Highway

The pouring timing of sealing hinge concrete for concrete-filled steel tube arch bridges directly affects the construction duration and the stress state of arch ribs. To clarify the structural response differences at different pouring timings, the Beiliuhe Extra-large Bridge on the Pingxi ‒ Cenxi Expressway in Guangxi Province was taken as the engineering background in this paper. A finite element model was established using Midas Civil, and the following four pouring timings of sealing hinge concrete were comparatively analyzed: immediately after the butt welding of sealing hinge steel pipes; after the closure of arch ribs and before the pouring of …

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Study On Calculation Method For Incremental Launching Based On Nonlinear Analysis, Mo Shanfeng, Huang Cailiang, Qin Hui Jun 2026

Study On Calculation Method For Incremental Launching Based On Nonlinear Analysis, Mo Shanfeng, Huang Cailiang, Qin Hui

Journal of China & Foreign Highway

In view of the shortcomings of traditional incremental launching calculation methods and the assembly construction control of incremental launching beams, an incremental launching calculation method based on nonlinear analysis was proposed in this paper. This method could truly simulate the running state where the incremental launching pier remains stationary, and the beam moves forward. The assembly alignment of all segments of the beam and the real alignment of the beam under specified working conditions could be directly output. The prefabricated alignment of the main beam (i.e., unstressed alignment) did not need to be consistent with the slide alignment. When the …

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Summary And Prospect Of Typical Diseases In Energy Transport Channels In Winter Cold Regions Over Past 20 Years, Jia Qinlong, Hou Zhongfei, Yin Yanping Jun 2026

Summary And Prospect Of Typical Diseases In Energy Transport Channels In Winter Cold Regions Over Past 20 Years, Jia Qinlong, Hou Zhongfei, Yin Yanping

Journal of China & Foreign Highway

To investigate the typical disease characteristics of energy transport channels in winter cold regions and guide the design for extending road service life, the causes of diseases such as pavement reflective cracks, continuous potholes on bridge decks, and failures of bridge drainage systems were analyzed based on the 20-year operation data of a 531 km in-service expressway in the coal energy region of northern Shaanxi. The research results indicate that when the asphalt pavement thickness reaches 22 cm, the reflective crack spacing of the expressway operated for 15 years can be controlled to over 50 m. Basically, no base layer …

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Hybrid Solar - Coal Thermal Energy System For Industrial Process Heat At Sayona Drinks Limited In Tanzania, Santos Kihwele, Elisha D. Bitesigirwe Jun 2026

Hybrid Solar - Coal Thermal Energy System For Industrial Process Heat At Sayona Drinks Limited In Tanzania, Santos Kihwele, Elisha D. Bitesigirwe

Tanzania Journal of Engineering and Technology (TJET)

Over the past two decades, global efforts to mitigate pollution from conventional energy sources have intensified, with coal remaining a major contributor to carbon emissions. While fossil fuels cannot be eliminated from thermal generation in manufacturing industries, particularly in middle‑income countries such as Tanzania, they continue to dominate as the primary energy source. Industries including food and beverage, paper, textile, paints, chemicals, and pharmaceuticals require substantial thermal energy for heating and drying, and typically rely on coal and natural gas.This study introduces a unique application of a parabolic trough solar thermal system with integrated thermal energy storage, specifically tailored to …

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Teachers’ Awareness Of Family Engagement In Multilingual Education, Sedighe Zamani Roodsari Jun 2026

Teachers’ Awareness Of Family Engagement In Multilingual Education, Sedighe Zamani Roodsari

Journal of Multicultural Affairs

This study investigated public school teachers’ awareness of family engagement as a linguistic and cultural resource for multilingual students. Multilinguals are typically described as individuals who can communicate in more than one language, with English not being their native language, and their linguistic choices are influenced by societal norms and systems (Šifrar Kalan et al., 2024; Wei, 2008). Preparing pre-service teachers to enhance opportunities for multilingual students remains a critical need in teacher education programs, as they strive to move beyond monolingual ideologies in their teaching practices (Cárdenas Curiel et al., 2024; Kim & Choi, 2020; Williams & Ewing, 2019). …

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Binding Energy Of Muonic Beryllium: Perturbative Versus All-Order Calculations, Shikha Rathi, Ulrich D. Jentschura, Paul Indelicato, Ben Ohayon Jun 2026

Binding Energy Of Muonic Beryllium: Perturbative Versus All-Order Calculations, Shikha Rathi, Ulrich D. Jentschura, Paul Indelicato, Ben Ohayon

Physics Faculty Research & Creative Works

We compute the ground-state binding energy of muonic (Formula presented) (Formula presented) Be in two ways: first, the fully perturbative treatment of the nuclear-size effect often employed in light systems, and second, an approach that accounts for the finite-nuclear-size to all orders (and is inspired by calculations otherwise employed for heavy muonic ions). The results are compared term by term and show that both approaches agree to better than one part-per-million of the total energy. The objective of this work is twofold. The first is practical: to provide a parameterization that allows the extraction of the (Formula presented) (Formula presented) …

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Examining Nitrate Concentrations In Rainwater In The Marine Boundary Layer In St. Petersburg, Sam Irvine, Anson Kirsch, Ben Lloyd '25, Yasin Elshorbany, James Ivey Jun 2026

Examining Nitrate Concentrations In Rainwater In The Marine Boundary Layer In St. Petersburg, Sam Irvine, Anson Kirsch, Ben Lloyd '25, Yasin Elshorbany, James Ivey

Student Research

Harmful algae blooms (HABs) are a common, natural phenomenon that occur in bodies of water. Karenia brevis is an algae species where, in excess, it can result in red tide events which deplete nutrients in the area, impacting aquatic life and releasing toxic gasses. Past research shows that K. brevis can grow through nutrient absorption in response to excess nitrate in water. This project sought to examine whether nitrates from rainfall are responsible for creating an increase in nitrogen concentrations in the water surrounding St. Petersburg which can lead to algae bloom growth. Results showed that rainwater has higher concentrations …

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Trustworthy Reinforcement Learning And Communication-Efficient Multi-Agent Systems, Rui Zuo Jun 2026

Trustworthy Reinforcement Learning And Communication-Efficient Multi-Agent Systems, Rui Zuo

Dissertations - ALL

The rapid proliferation of autonomous systems, such as Unmanned Aircraft Systems (UAS) transitioning to large-scale Beyond Visual Line of Sight (BVLOS) operations, demands a paradigm shift toward reliable, transparent, and resilient autonomy. While Deep Reinforcement Learning (DRL) and Multi-Agent Reinforcement Learning (MARL) have demonstrated exceptional capabilities in complex decision-making and coordination, their real-world deployment in safety-critical domains is hindered by two fundamental challenges. First, the opaque, "black-box" nature of DRL models prevents human operators from understanding and trusting the agents' underlying logic. Second, as multi-agent operations scale, they become severely constrained by the stochastic link qualities and strict bandwidth limitations …

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Atropisomer Mechanochemistry Of Diarylethene Mechanophores: A Study Of Structure-Mechanical Activity Relationships, Cijun Zhang Jun 2026

Atropisomer Mechanochemistry Of Diarylethene Mechanophores: A Study Of Structure-Mechanical Activity Relationships, Cijun Zhang

Dissertations - ALL

Stimuli-responsive organic structures are advanced, intelligent platforms that dynamically adjust their physical or chemical properties—such solubility, or color—in response to external stimuli including light, heat, pH, redox conditions, mechanical force, or magnetic fields. Among these structures, mechanophores represent an important class that is specifically responsive to mechanical force. Synthetic mechanophores can be rationally engineered to exhibit tunable mechanosensitivity as well as tailored chemical and physical properties. In this work, we designed and synthesized a type of atropisomeric mechanophores based on sterically congested diarylethene photoswitches, and systematically investigated their mechanical and photochemical properties. Chapter 1 Chapter 1 provides a general introduction …

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Scaling Logical Reasoning On Modern Hpc Hardware, Yihao Sun Jun 2026

Scaling Logical Reasoning On Modern Hpc Hardware, Yihao Sun

Dissertations - ALL

Deductive logic reasoning has evolved from a theoretical symbolic artificial intelligence tool into a massive computational workload. Modern domains, ranging from static program analysis and binary reverse engineering to knowledge-graph reasoning, rely on Datalog, a logical query language, to express deeply recursive, declarative specifications. However, scaling logic reasoning to these industrial workload exposes two interlocking ceilings in traditional engines. Architecturally, the memory bandwidth and parallel throughput of single-node CPUs fall drastically short of the read- and write-heavy demands of semi-naive evaluation. Asymptotically, traditional query processing algorithms, such as binary join algorithms generate massive intermediate relations that exhaust device memory on …

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On The Extension Conjecture For Koszul Algebras, Benjamin Kaufman Jun 2026

On The Extension Conjecture For Koszul Algebras, Benjamin Kaufman

Dissertations - ALL

We investigate questions related to the extension conjecture for finite-dimensional algebras. Suppose $\Lambda = \kk Q/I$ is a finite-dimensional algebra given by a quiver with relations. The extension conjecture asserts that if $S$ is a simple right $\Lambda$-module corresponding to a vertex with a loop, that is, $\Ext_\Lambda^1(S,S)\neq 0$, then $\Ext^n_\Lambda(S,S)\neq 0$ for infinitely many $n$. We show that one can obtain information about the non-vanishing of the extensions $\Ext^n_\Lambda(S,S)$ by looking at the graded Cartan matrix and its inverse. We use this connection to prove the extension conjecture for standardly graded $\kk$-algebras on two vertices with Loewy length at …

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Using Low-Frequency Vibrational Spectroscopy To Develop Analytical Profiles For Polymorphic Organic Molecular Crystals, Salvatore Zarrella Jun 2026

Using Low-Frequency Vibrational Spectroscopy To Develop Analytical Profiles For Polymorphic Organic Molecular Crystals, Salvatore Zarrella

Dissertations - ALL

Low-frequency vibrational spectroscopy provides a sensitive approach for characterizing polymorphism and intermolecular dynamics in organic molecular crystals. Terahertz time-domain spectroscopy (THz-TDS) and low-frequency Raman spectroscopy probe collective lattice vibrations arising from weak intermolecular interactions, offering direct insight into crystal packing, phase stability, and structural organization that is often inaccessible to conventional diffraction and mid-infrared techniques. To interpret these modes, experimental measurements are combined with periodic solid-state density functional theory (ss-DFT), which enables vibrational assignments to specific intermolecular motions, and crystal structure prediction (CSP), which maps accessible polymorphic energy landscapes. Together, these methods form a unified experimental–computational framework for understanding molecular …

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(R2077) Enhancing Queue Management: Dynamic Server Allocation And Optional Services In Stochastic Modeling, G. Ayyappan, S. Sankeetha Jun 2026

(R2077) Enhancing Queue Management: Dynamic Server Allocation And Optional Services In Stochastic Modeling, G. Ayyappan, S. Sankeetha

Applications and Applied Mathematics: An International Journal (AAM)

Consider a queueing system with a single server, where customer arrivals follow a Markovian arrival process and service times follow a phase-type distribution. The main server has the capability to recruit an additional server when the number of customers in the system exceeds a certain threshold, denoted as L. Both servers provide normal service to customers, and optional service is provided upon request. The main server takes multiple vacations, with the durations following an exponential distribution with rate parameter η, until there is at least one customer in the system. This system can be represented as a Markov chain process, …

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(R2142) Queueing System With Batched Services, Server-Controlled Re-Service, Set-Up Time And Multiple Vacation, S. Karpagam, N. Aarthy, B. Somasundaram Jun 2026

(R2142) Queueing System With Batched Services, Server-Controlled Re-Service, Set-Up Time And Multiple Vacation, S. Karpagam, N. Aarthy, B. Somasundaram

Applications and Applied Mathematics: An International Journal (AAM)

To analyze a bulk queueing system with server-controlled admission for reservice, low-batch service, multiple vacation and set-up time. The study explores how the server dynamically adjusts between low-batch and bulk services based on the queue size. After completing a bulk service, the departing batch may request reservice with a certain probability. However, accepting the request is not mandatory, and the server admits it with some probability. Whenever the queue becomes empty, whether after reservicing, completing service with no reservice request, or ending the low-batch service, the server enters a random-length vacation. If the queue still has less than ‘a’ customers …

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