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Thinking Of Aerospace Equipment Systematization Simulation Technology Development, Weimin Bao, Zhenqiang Qi Jun 2024

Thinking Of Aerospace Equipment Systematization Simulation Technology Development, Weimin Bao, Zhenqiang Qi

Journal of System Simulation

Abstract: The aerospace field is flourishing in the new era. Aerospace equipment presents new characteristics such as systematization, new quality, high efficiency and intelligence. Simulation technology plays a more important role in the digital aerospace era as a means of enhancing efficiency and empowerment covering all stages of the entire lifecycle, including project demonstration, research and development, testing, manufacturing, training, and maintenance. The conception of aerospace equipment systematization simulation technology is introduced, the current development status and practices at home and abroad are elaborated, and the future development trends and challenges of aerospace equipment systematization simulation technology are evaluated. Focusing …

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Unsupervised Complex Condition Recognition Based On Stochastic Neighborhood Embedding, Lin Huang, Shanjun Liu, Wei Wang, Li Gong Jun 2024

Unsupervised Complex Condition Recognition Based On Stochastic Neighborhood Embedding, Lin Huang, Shanjun Liu, Wei Wang, Li Gong

Journal of System Simulation

Abstract: Modern industrial production equipment usually has a complex structure and runs alternately in different working conditions. Accurate working conditions identification based on monitoring data is the basis of health monitoring of the system, but the monitoring data of the system usually has a high dimension and a large data volume. To identify the complex equipment operating conditions, an unsupervised operating condition identification method based on stochastic neighborhood embedding is proposed. The stochastic neighborhood embedding algorithm can simultaneously preserve the local and global structural characteristics of the data, and also calculate the probability similarity of data points in high-dimensional and …

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Completion Time Simulation Prediction Method For Aircraft Assembly Process With Batch And Sortie, Changjian Jiang, Hu Fan, Tao Luo, Wen Yuan, Zehao He Jun 2024

Completion Time Simulation Prediction Method For Aircraft Assembly Process With Batch And Sortie, Changjian Jiang, Hu Fan, Tao Luo, Wen Yuan, Zehao He

Journal of System Simulation

Abstract: Aiming at the product differentiation analysis limitation of traditional discrete event simulation method, a simulation prediction method for aircraft assembly process with batch and sortie is proposed. Around the aircraft sortie number, the formal definition of various basic elements and interactions in the assembly process with batch and sortie is studied, and the construction of station and whole line simulation model is carried out. The simulation promotion framework and execution mechanism supporting the product differentiation analysis are studied. Based on the simulation results, a method for predicting the completion time of sorties based on interval estimation method is proposed. …

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Adaptive Pid Control Algorithm Based On Ppo, Zhiyong Zhou, Fei Mo, Kai Zhao, Yunbo Hao, Yufeng Qian Jun 2024

Adaptive Pid Control Algorithm Based On Ppo, Zhiyong Zhou, Fei Mo, Kai Zhao, Yunbo Hao, Yufeng Qian

Journal of System Simulation

Abstract: A six-axis robotic arm is built and simulated in a complex control environment with disturbances by using MATLAB physics engine and Python, which provides a trial-and-error environment for the robotic arm training that could not be provided in reality. Proximal policy optimization(PPO) algorithm in reinforcement learning is proposed to improve the traditional PID control algorithm. By introducing the multi-agent idea and on the basis of the different effects of the three parameters of PID on control system and the characteristics of the six-axis robotic arm, the three parameters are separately trained as different intelligent individuals to achieve a new …

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Fusing Rotation Angle Coding In Spherical Space For Human Action Recognition, Benyue Su, Bangguo Zhu, Mengjuan Guo, Min Sheng Jun 2024

Fusing Rotation Angle Coding In Spherical Space For Human Action Recognition, Benyue Su, Bangguo Zhu, Mengjuan Guo, Min Sheng

Journal of System Simulation

Abstract: The existing human action recognition methods focus more on the translation information such as the coordinates and displacements of skeleton structure, and pay less attention to the motion trend of skeleton structure and the rotation information representing the motion direction of joints and bones. A spatio-temporal convolutional neural network method combining the rotation angle coding in spherical space is introduced. The angle information with scale invariance is obtained by mapping the human action in three-dimensional spherical space, and the dynamic angular velocity information is extracted as the angle code to represent the rotation information of joints and bones in …

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Design Of Real-Time Simulation & Test Software Based On Windows/Rtx, Yongbo Li, Runmei Tian, Hui Zhang, Shanpeng Guo, Qi Li Jun 2024

Design Of Real-Time Simulation & Test Software Based On Windows/Rtx, Yongbo Li, Runmei Tian, Hui Zhang, Shanpeng Guo, Qi Li

Journal of System Simulation

Abstract: Aiming at the limited real-time performance of traditional test software and the low generality of traditional simulation interface software, a real-time simulation software based on Windows/RTX is designed to meet the requirements of unit testing and control system simulation verification of semiphysical simulation software. Through modular design, GUI layer human-computer interface and RTX layer real-time operation program are developed. To ensure the real-time, the lock-free cyclic buffer plus dual-threading technology is used to solve the timeout problem of serial data transmission and reception when the simulation step size is 1 ms under RTX environment. A timeout detection algorithm is …

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Cooperative Ant Colony Algorithm Combining Evaluation Reward And Punishment Mechanism And Neighborhood Dynamic Degradation, Yujie Wang, Xiaoming You, Sheng Liu Jun 2024

Cooperative Ant Colony Algorithm Combining Evaluation Reward And Punishment Mechanism And Neighborhood Dynamic Degradation, Yujie Wang, Xiaoming You, Sheng Liu

Journal of System Simulation

Abstract: To address the slow convergence and the tendency to fall into local optimality in solving TSP, a cooperative ant colony algorithm combining evaluation reward and punishment mechanism and neighborhood dynamic degradation (ENCACO) is proposed. The paths are classified into active and abandon paths according to the path evaluation value, and with the path evaluation value as the weight, the different pheromone reward and punishment strategies are adopted for the two types of paths to accelerate the convergence speed of the algorithm. Through the neighborhood dynamic degradation strategy, and the neighborhood radius is used to divide the set of cities …

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Construction Of A Virtual Interactive System For Orchards Based On Digital Twin, Hongjun Wang, Junqiang Lin, Xiangjun Zou, Po Zhang, Mingxuan Zhou, Weirui Zou, Yunchao Tang, Lufeng Luo Jun 2024

Construction Of A Virtual Interactive System For Orchards Based On Digital Twin, Hongjun Wang, Junqiang Lin, Xiangjun Zou, Po Zhang, Mingxuan Zhou, Weirui Zou, Yunchao Tang, Lufeng Luo

Journal of System Simulation

Abstract: Aiming at the low visibility, poor real-time, weak adaptability and single interaction mode in orchard planting management system, a six-dimensional model of orchard digital twin system for planting management process is proposed. The system model construction theory and technology system is discussed from four aspects, entity modeling of management elements, dynamic modeling of management process, simulation modeling of management system and optimization modeling of management strategy. Based on the six-dimensional model, supported by the theory and technology system, the virtual interactive system architecture of the orchard based on the digital twin is designed, and the key technologies of the …

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Black Men Who Participate In An Urban Community College Men Of Color Initiative: A Phenomenological Study, Steven Hardy Jun 2024

Black Men Who Participate In An Urban Community College Men Of Color Initiative: A Phenomenological Study, Steven Hardy

Theses and Dissertations

This phenomenological study explored the perceptions and experiences of Black men who participated in the MOCI. The study uncovered insights into what aspects of the program were effective and where improvements could be made according to the student participants. Employing a phenomenological design, the research identified commonalities among the participants' experiences (Creswell & Creswell, 2018; Moustakas, 1994; Rubin & Rubin, 2012). The structure of understanding surrounding participants in the MOCI program was meticulously facilitated using phenomenology (Creswell & Creswell, 2018). The interviews were not just semi-structured but also empathetic, with prepared open-ended questions followed by probing inquiries, all aimed at …

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Study Of Modified Salinomycin Analogs On Inhibition Of Triple Negative Breast Cancer Metastasis And Invasion, Farnaz Malekmarzban Jun 2024

Study Of Modified Salinomycin Analogs On Inhibition Of Triple Negative Breast Cancer Metastasis And Invasion, Farnaz Malekmarzban

Theses and Dissertations

Triple negative breast cancer (TNBC) is a more aggressive type of breast cancer which contains faster growth, higher metastasis rate and worse prognosis. The main challenge toward treatment of this type of cancer is being heterogeneous. Recently, Salinomycin (SAL) has been considered as a potential agent for triple negative breast cancer treatment. However, chemical modification of SAL is needed to improve SAL selectivity to cations and decrease its cytotoxicity. The purpose of this study was to evaluate the effect of chemically modified analogs of SAL on the viability, metastasis, Wnt pathway as well as angiogenesis of Triple negative breast cancer …

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Updated Catalog Of Kepler Planet Candidates: Focus On Accuracy And Orbital Periods, Jack J. Lissauer, Jason F. Rowe, Daniel Jontof-Hutter, Daniel C. Fabrycky, Eric B. Ford, Darin Ragozzine, Jason H. Steffen, Kadri M. Nizam Jun 2024

Updated Catalog Of Kepler Planet Candidates: Focus On Accuracy And Orbital Periods, Jack J. Lissauer, Jason F. Rowe, Daniel Jontof-Hutter, Daniel C. Fabrycky, Eric B. Ford, Darin Ragozzine, Jason H. Steffen, Kadri M. Nizam

Pacific Faculty Work

We present a new catalog of Kepler planet candidates that prioritizes accuracy of planetary dispositions and properties over uniformity. This catalog contains 4376 transiting planet candidates, including 1791 residing within 709 multiplanet systems, and provides the best parameters available for a large sample of Kepler planet candidates. We also provide a second set of stellar and planetary properties for transiting candidates that are uniformly derived for use in occurrence rate studies. Estimates of orbital periods have been improved, but as in previous catalogs, our tabulated values for period uncertainties do not fully account for transit timing variations (TTVs). We show …

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Advancing Influence In Social Networks Based On Game Theory, Adedamola Adesokan Jun 2024

Advancing Influence In Social Networks Based On Game Theory, Adedamola Adesokan

Electrical and Computer Engineering ETDs

Online Social Networks (OSNs) have become part of our everyday life, as a means of interacting with people, sharing content, attending events, etc. Influencers are professional OSN users, who have a large loyal audience and use the OSNs to market various goods or services based on brand partnerships. In this thesis, we introduce a novel mechanism to enable OSN users to become influencers by strategically deciding their activity within the OSN. Initially, the concepts of social coordinates and social communities are proposed. Then, a non-cooperative game is introduced to enable the users to make optimal decisions regarding their activity in …

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Strategies For Resilient Build Back In The Post-Flood Era: An Ahp-Dematel Technique, Muhammad Tahir, Mohd Fadzil Bin Mohd Idris Jun 2024

Strategies For Resilient Build Back In The Post-Flood Era: An Ahp-Dematel Technique, Muhammad Tahir, Mohd Fadzil Bin Mohd Idris

CSID Journal of Infrastructure Development

Pakistan suffered from devastating floods in 2022, causing extensive infrastructural, economic, social, and other damages. Effective risk management was notably absent in the country. Therefore, this paper identifies critical factors influencing the build-back-better (BBB) framework and resilience building. The evaluation of various strategies for risk reduction in infrastructure during floods, ensuring its resilience, is also addressed. This study employs Multi-Criteria Decision Making (MCDM) techniques, specifically the Analytic Hierarchy Process (AHP) and the Decision-Making Trial and Evaluation Laboratory (DEMATEL), to assess critical factors in BBB in the context of devastating floods. The AHP analysis effectively ranked the identified factors based on …

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Simulation Of Robotic Peg-In-Hole Assembly Strategy Based On Drl, Zilu Zhu, Yongkui Liu, Lin Zhang, Lihui Wang, Tingyu Lin Jun 2024

Simulation Of Robotic Peg-In-Hole Assembly Strategy Based On Drl, Zilu Zhu, Yongkui Liu, Lin Zhang, Lihui Wang, Tingyu Lin

Journal of System Simulation

Abstract: Aiming at the existing peg-in-hole assembly method problems of dependence on accurate contact state models, difficulties in data acquisition, low sampling efficiency, and poor security, a simulation research method for robot peg-in-hole assembly strategy based on DRL is proposed. A simulation environment of robot peg-in-hole assembly based on ROS-Gazebo is built, and a method of gravity compensation for force/torque sensor based on a least square method is proposed. The reinforcement learning paradigm is employed to model the robot peg-in-hole assembly, and a method based on soft actor-critic(SAC) algorithm is proposed. The communication mechanism between the simulation environment and the …

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Manufacturing Of Aligned Electrospun Nanofiber Yarns For Their Enhanced Mechanical And Piezoelectric Properties, Adaugo Mary-Frances Enuka Jun 2024

Manufacturing Of Aligned Electrospun Nanofiber Yarns For Their Enhanced Mechanical And Piezoelectric Properties, Adaugo Mary-Frances Enuka

Theses and Dissertations

Electrospinning is a widely used technique for producing nanofibers with diverse applications. This method uses polymer solutions and strong electric fields to generate nano-sized fibers with unique properties. This study presents a novel manufacturing approach that enables the production of electrospun poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) nanofiber yarns using an automated parallel track system and an adjustable roll-to-roll collector. This research examines the impact of an automated post-drawing system on the polymer chain orientation, crystallinity, tensile strength, morphology, and piezoelectric properties of PVDF-HFP nanofiber yarn. The results reveal that the post-drawing process significantly improves molecular alignment, increases tensile strength, and enhances the …

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The Fate Of Fixed Nitrogen In Santa Barbara Basin Sediments During Seasonal Anoxia, Xuefeng Peng, David J. Yousavich, Annie Bourbonnais, Frank Wenzhöfer, Felix Janssen, Tina Treude, David L. Valentine Jun 2024

The Fate Of Fixed Nitrogen In Santa Barbara Basin Sediments During Seasonal Anoxia, Xuefeng Peng, David J. Yousavich, Annie Bourbonnais, Frank Wenzhöfer, Felix Janssen, Tina Treude, David L. Valentine

Faculty Publications

Despite long-standing interest in the biogeochemistry of the Santa Barbara Basin (SBB), there are no direct rate measurements of different nitrogen transformation processes. We investigated benthic nitrogen cycling using in situ incubations with 15NO 3̅  addition and quantified the rates of total nitrate (NO 3̅) uptake, denitrification, anaerobic ammonia oxidation (anammox), N2O production, and dissimilatory nitrate reduction to ammonia (DNRA). Denitrification was the dominant NO 3̅ reduction process, while anammox contributed 0 %–27 % to total NO 3̅ reduction. DNRA accounted for less than half of NO 3̅ reduction except at the …

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Considerations For Quality Control Monitoring Of Machine Learning Models In Clinical Practice, Louis Faust, Patrick Wilson, Shusaku Asai, Sunyang Fu, Hongfang Liu, Xiaoyang Ruan, Curt Storlie Jun 2024

Considerations For Quality Control Monitoring Of Machine Learning Models In Clinical Practice, Louis Faust, Patrick Wilson, Shusaku Asai, Sunyang Fu, Hongfang Liu, Xiaoyang Ruan, Curt Storlie

Faculty, Staff and Student Publications

Integrating machine learning (ML) models into clinical practice presents a challenge of maintaining their efficacy over time. While existing literature offers valuable strategies for detecting declining model performance, there is a need to document the broader challenges and solutions associated with the real-world development and integration of model monitoring solutions. This work details the development and use of a platform for monitoring the performance of a production-level ML model operating in Mayo Clinic. In this paper, we aimed to provide a series of considerations and guidelines necessary for integrating such a platform into a team's technical infrastructure and workflow. We …

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The Effect Of A Contextualized Dosage Calculation Learning Intervention On Pre-Nursing Students' Math Self-Efficacy And Ability To Pass High Stakes Dosage Calculation Examination On First Attempt, Eileen V. Weatherby Jun 2024

The Effect Of A Contextualized Dosage Calculation Learning Intervention On Pre-Nursing Students' Math Self-Efficacy And Ability To Pass High Stakes Dosage Calculation Examination On First Attempt, Eileen V. Weatherby

Dissertations

Many students in pre-licensure nursing programs struggle with calculating accurate medication dosages even though they meet the numeracy requirements for application to the nursing programs. Most pre-licensure programs require that nursing students pass dosage calculation exams at a specified level of accuracy before progressing to the next term. Students typically have three tries to pass at the specified level and should they not succeed, they must withdraw. If they wish to continue in the program, they must complete the requirements for reentry which may include space availability restrictions. Factors influencing dosage calculation performance include fear of mathematics, low math self-efficacy, …

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Monitoring Water Meniscus Formation At Nanocontacts With Shear-Force Acousto Near-Field Microscopy, Xiaohua Wang, Rodolfo Fernandez, Theodore Brockman, Kacharat Supichayanggoon, Andres H. La Rosa Jun 2024

Monitoring Water Meniscus Formation At Nanocontacts With Shear-Force Acousto Near-Field Microscopy, Xiaohua Wang, Rodolfo Fernandez, Theodore Brockman, Kacharat Supichayanggoon, Andres H. La Rosa

Physics Faculty Publications and Presentations

Shear-force acoustic near-field microscopy (SANM) is employed to monitor stochastic formation and post dynamic response of a water meniscus that bridges a tapered gold probe (undergoing lateral oscillations of a few nanometers amplitude at constant frequency) and a flat (gold or silicon oxide) substrate. As the probe further approaches the substrate, its amplitude decreases. Shear forces (of yet unknown precise origin) are typically invoked to explain the apparently pure damping effects affecting the probe's motion. Herein, SANM measurements underscore instead the role of near-field acoustic emission from the water meniscus as an elastic energy dissipation channel involved in shear interactions. …

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Matrix Processing With Photonic Analog Computing, James Michael Garofolo Jun 2024

Matrix Processing With Photonic Analog Computing, James Michael Garofolo

Theses and Dissertations

In the digital age, a wide variety of engineering problems have been solved, to a great deal of success, by digital computing techniques. The flexibility of software and relatively low cost of digital computing hardware make it an ideal starting point for solving a majority of tasks, and the numerical stability of software solutions make it highly appealing as the major workhorse for computational tasks. Despite this, many problems are actually suboptimally solved by digital methods, leading to systems with high latency, low throughput, power hungry parallel processing units and an excess of memory for discretizing sensor inputs. Computational photonic …

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Analysis Of The Pid Controller Parameters For A Surface Mobility Platform Mobile Robot, Lwin Ma Ma Maung, Aung Myat San, Wai Mar Myint, Wut Yi Win, Min Thu Soe Jun 2024

Analysis Of The Pid Controller Parameters For A Surface Mobility Platform Mobile Robot, Lwin Ma Ma Maung, Aung Myat San, Wai Mar Myint, Wut Yi Win, Min Thu Soe

Platform: A Journal of Engineering (PAJE)

Surface mobility control is a fundamental challenge in robotics, and its applications range from autonomous vehicles to industrial automation. The main aim of the paper is to analyse the PID controller parameters for the speed control of a surface mobility platform mobile robot. MATLAB simulation toolbox and mathematical model of the DC motor are used to find the optimal PID controller parameters to complete the DC motor speed control system. For the SMP motion control system, the mobile robot kinematic model is supported as a differential drive system. In this paper, the PID controller parameters for the DC motor control …

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Dynamic Air Defense Resource Allocation Optimization Based On Improved Differential Evolution Algorithm, Tianyu Luo, Lining Xing, Rui Wang, Ling Wang, Jianmai Shi, Xin Sun Jun 2024

Dynamic Air Defense Resource Allocation Optimization Based On Improved Differential Evolution Algorithm, Tianyu Luo, Lining Xing, Rui Wang, Ling Wang, Jianmai Shi, Xin Sun

Journal of System Simulation

Abstract: Based on the integrated performance of weapon equipments such as radars, launchers and missiles, a mixed-integer decision model that minimizes the total target intercept value and the probability of survival based on Target-Set, Resource-Set is developed. A new improved differential evolutionary algorithm has been introduced to solve the problem, and the initial solutions is generated by using the reverse learning strategies to ensure the quality of the initial populations. An inspiration rule for the fast repair and reconstruction is designed to work at multi-stage to improve the search capability of the algorithm. The simulation experiment results show the algorithm's …

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Research On Operational Protection Area Of Ils Glide Slope, Qingdong Li, Jiaquan Ye, Jian Xu Jun 2024

Research On Operational Protection Area Of Ils Glide Slope, Qingdong Li, Jiaquan Ye, Jian Xu

Journal of System Simulation

Abstract: The scientific protection for the operational protection area of the instrument landing system glide slope is of great significance to ensure the quality of civil aviation navigation space signals, the safety of aircraft approach operations, and the efficiency of airport operations. Combined with the concept evolution of the glide slope operational protection area, a comparative analysis of the delineation of the glide slope operational protection area required by the national civil aviation standards, industry standards, and Annex 10 Volume I of the Convention on International Civil Aviation is carried out. Taking the extra-large aircraft (A380-800) as an example, the …

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Air Defense Missile Weapon Target Assignment Based On Multi-Objective Evolutionary Algorithm, Xin Sun, Lining Xing, Rui Wang, Ling Wang, Jianmai Shi, Tianyu Luo Jun 2024

Air Defense Missile Weapon Target Assignment Based On Multi-Objective Evolutionary Algorithm, Xin Sun, Lining Xing, Rui Wang, Ling Wang, Jianmai Shi, Tianyu Luo

Journal of System Simulation

Abstract: An effective weapon target assignment method can reduce the combat losses and improve the defense effect. A reasonable mathematical model is established for the allocation of air defense resources, aiming at the optimization objectives of maximizing target destruction effectiveness and minimizing radar resource consumption, considering multiple constraints such as the upper limit of radar channels, on the basis of multiobjective evolutionary algorithm based on decomposition (MOEA/D), the probability of crossover and mutation is adaptively adjusted to improve the quality of individuals in the process of population evolution, and a set of optimal solution sets for decision makers is obtained. …

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Classification Cooperative Scheduling Of U-Automated Container Terminal Based On Container Markers, Fei Wang, Daofang Chang, Furong Wen Jun 2024

Classification Cooperative Scheduling Of U-Automated Container Terminal Based On Container Markers, Fei Wang, Daofang Chang, Furong Wen

Journal of System Simulation

Abstract: To improve the confusing scheduling of U-shaped yard operations due to improper classification of containers, the classification cooperative scheduling process is proposed, in which the classification cooperative scheduling model is established with the constraints of coordinated operation and efficient independent operation. The container classification principle and the container multiple stacking principle are proposed, the stacking point is selected by the weighted calculation based on the container operation mark to design the penalty mechanism, and the classification cooperative heuristic algorithm solution model is designed. Comparative experiments show that the strategy used in the algorithm is superior,which can reduce the equipment …

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Optimal Trajectory Of Full-Duplex Uav Relaying Over Hybrid Probability Channels, Tao Wang, Ji Xiaodong Jun 2024

Optimal Trajectory Of Full-Duplex Uav Relaying Over Hybrid Probability Channels, Tao Wang, Ji Xiaodong

Journal of System Simulation

Abstract: A fixed-wing UAV being the full-duplex moving relay, and a hybrid probability channel being the source to send data to the destination, through the flight optimal trajectory design. On the basis of ensuring the total data amount of source-destination communication, the energy consumption of the system is minimized. Two optimization problems of runway shape and mixed trajectory are established, which are non-convex and are difficult to get the closed-form solution. The hybrid probability channels gains are replaced by the average channel gains, and the lower bounds of the received data at the UAV and the destination are calculated by …

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Arterial Coordination Optimization Method Based On Vehicle Speed Guidance And Inductive Control, Mingjun Deng, Xinxia Hu, Xiang Li, Liping Xu Jun 2024

Arterial Coordination Optimization Method Based On Vehicle Speed Guidance And Inductive Control, Mingjun Deng, Xinxia Hu, Xiang Li, Liping Xu

Journal of System Simulation

Abstract: Arterial signal coordination is usually based on fixed belt speeds and time-of-day statistical flows. Actually, vehicle speeds and traffic flows are fluctuating, which causes to the mismatch between the signal scheme and the actual optimal belt speeds and traffic flow demands, and affects the intersection's traffic efficiency. Based on the vehicle infrastructure cooperation, by applying Maxband model and the maximum green wave bandwidth, the minimum number of arterial vehicle delays, arterial stops and the minor direction delays being the optimization objectives, a multi-objective optimization model for arterial signal coordination is established. Through using an improved multi-objective particle swarm algorithm …

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Curriculum Learning-Based Simulation Of Uav Air Combat Under Sparse Rewards, Jingyu Zhu, Hongli Zhang, Minchi Kuang, Heng Shi, Jihong Zhu, Zhi Qiao, Wenqing Zhou Jun 2024

Curriculum Learning-Based Simulation Of Uav Air Combat Under Sparse Rewards, Jingyu Zhu, Hongli Zhang, Minchi Kuang, Heng Shi, Jihong Zhu, Zhi Qiao, Wenqing Zhou

Journal of System Simulation

Abstract: To address the limited exploration capabilities and sparse rewards of conventional reinforcement learning methods in air combat environment, a curriculum learning distributed proximal policy optimization (CLDPPO) reinforcement learning algorithm is proposed. A reward function informed by professional empirical knowledge is integrated, a discrete action space is developed, and a global observation and local value and decision network featuring separated global and local observations is established. A methodology for unmanned aerial vehicles UAVs is presented to acquire combat expertise through a sequence of fundamental courses that progressively intensify in their offensive, defensive, and comprehensive content. The experimental results show that …

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Repair And Surface Functionalization Of Fiber Reinforced Polymer Composites By Cold Spray, Ibnaj Anamika Anni Jun 2024

Repair And Surface Functionalization Of Fiber Reinforced Polymer Composites By Cold Spray, Ibnaj Anamika Anni

Theses and Dissertations

Fiber-reinforced polymer composites are widely used in industries and applications such as energy, automotive, defense, and aerospace. This study investigates the application of polymer cold spray, an emerging additive manufacturing process, for coating and repair of fiber-reinforced polymer (FRP) composites. The research starts with feasibility studies focused on the cold spray deposition of thermoplastic nylon-6 particles on woven glass fiber-reinforced composites (GFRP). A parametric study determines critical process parameters window, ensuring successful deposition and bonding without compromising the macroscale mechanical behavior. These findings indicate that the cold spray process does not adversely affect the fiber integrity or surface quality of …

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Chemotherapy Drug Release From Hollow Core Polyethyleneimine Nanoparticles, Brian Boyle Jun 2024

Chemotherapy Drug Release From Hollow Core Polyethyleneimine Nanoparticles, Brian Boyle

Theses and Dissertations

Novel anticancer delivery vehicles are arising from engineered nanostructured materials. This work involved the synthesis, characterization, and release of novel hollow core polymeric nanoparticles (HCPNPs) for controlled drug delivery. Polyethyleneimine (PEI) was bound to AuNPs, forming polymer-shell nanoparticles with dissolution of the gold core via iodine forming HCPNPs with drug intercalated DNA bound to the surface. A high density (85 molecules/particle) of DNA intercalated with daunorubicin was conjugated. Particles were spherical with an average diameter of 105.7 ± 17.3 nm and zeta potential of 20.4 ± 3.54 mV. We hypothesize the DNA backbone electrostatically condensed to the primary amines on …

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