Systems Science Commons^™

Design And Research Of A Microfocus X-Ray Tube, Haodong Zhao, Shizong Wei, Daolong Yu, Zhixia Liu, Yuezhong Chen, Ji Xu

Journal of System Simulation

Abstract: With the rapid advancement of high-resolution imaging and Micro-nano detection technology, microfocus X-ray sources show great potential for applications in industrial non-destructive testing, biomedical imaging, and material microstructure analysis. Achieving a focal spot size below 10 μm is essential for enhancing spatial resolution. However, traditional X-ray tubes are constrained by heat source dimensions, electron beam divergence, and limited focusing capabilities, which makes it challenging to simultaneously achieve focal spot miniaturization and adequate radiation intensity. In this study, a hot cathode electron gun is modeled using CST particle studio. Simulations are conducted to analyze the influence of the first anode …

Research On Characteristics Of Inclined Jet Flow For Aircraft De-Icing Based On Multiphysics Coupling, Zhiwei Xing, Hongbin Zhang, Ke Sun, Wenliang Miao

Journal of System Simulation

Abstract: To address the complex multiphysics coupling and lack of theoretical guidance for spray parameters in aircraft ground de-icing, a simulation model based on the Phase-Field method and Realizable k-ε turbulence model is proposed to investigate inclined jet flow over airfoil surfaces. The model enables the numerical reconstruction of jet impingement, liquid film flow, and unsteady heat transfer processes, providing a framework to elucidate the regulatory mechanisms of jet angles on momentum distribution and thermal characteristics. The simulation results reveal distinct variations in the flow and heat-transfer characteristics at different jet inclination angles. At a jet angle of 15°, the …

Physics-Driven Efficient Simulation Platform For Warhead-Target Engagement And Damage Assessment, Yidan Cui, Jingyao Ke, Yufeng Zheng, Kun Xue

Journal of System Simulation

Abstract: To address the limitations of incomplete physical modeling, low computational efficiency, fragmented simulation workflows, and insufficient visual immersion in existing damage simulations of fragment warheads, this paper proposes and develops a physics-driven, high-efficiency visualization platform for warhead-target engagement and damage assessment. The platform implements a full-chain, closed-loop simulation framework covering scenario configuration, force-field computation, fragment dispersion, warhead-target intersection, and damage evaluation. A finite element-discrete element (JK2024-06) coupled dynamics framework is established, integrating a detonation model, shell expansion correction, and fragment velocity inheritance to accurately reproduce the complete dynamic process from detonation to dispersion. A three-level acceleration algorithm based on …

Research On Simulation Technology Of Sea Yawing Test For Amphibious Vehicles, Yue Zhong, Wenlong Ji, Shiqi Feng, Feng Xu, Shuangping Ye

Journal of System Simulation

Abstract: Addressing the challenges of achieving extreme operating conditions and understanding the boundary conditions of yaw performance in offshore yaw tests for amphibious vehicles, a heading-flow direction angle mapping analysis method based on computational fluid dynamics (CFD) simulation and a three-dimensional hydrodynamic stratified model is proposed. Under environmental conditions of second-level (wave height of 0.5 m, wind speed of 3.3 m/s) and third-level (wave height of 1.0 m, wind speed of 5.1 m/s) sea states, a hundred-meter yaw test is simulated to reveal the nonlinear evolution law of yaw displacement and heading-flow direction angle. The research indicates that the extreme …

Vibration Characteristics Of Compact Hydraulic System Pipelines Based On Two-Way Fluid- Structure Interaction, Lichen Shi, Xujia Feng, Weitao Dou, Yanyan Li

Journal of System Simulation

Abstract: Amid growing demands for green manufacturing, equipment miniaturization, and high efficiency, compact hydraulic systems are critical in disassembly, assembly, and transport operations due to their high power density and flexibility. However, severe vibration in the pipeline systems significantly compromises equipment reliability. This study investigates the dynamic response mechanism of a compact on-board hydraulic pipeline system, using a specific piece of disassembly and assembly equipment with spatially constrained clamp placement as a case study, through a two-way fluid-structure interaction method, and optimizes the clamp layout. The results show that resonance occurs when the excitation frequency of the hydraulic oil pressure …

Research On Automated Generation Method Of Data-Based Architectural View Products, Kui Wang, Tianrong Gao, Cheng Chen, Mengyin Cui, Ping Wang, Xiaoping Wang, Huaijin Ge

Journal of System Simulation

Abstract: To address the issue of insufficient consistency among view products in the architectural design process, this paper proposes an automatic view product generation method based on the architecture metamodel. To enhance the consistency of view products, the method abandons the traditional post-design verification approach. Instead, it uses the information flow/data flow defined in the metamodel as the benchmark, and through explicit associations among architectural data as well as mapping relationships between view products and data, automatically derives and generates behavioral view products from structural and classificational view products. A prototype tool developed based on this method has been validated …

Research Of Data-Model Integrated Digital Twin-Based Health Intelligent Monitoring For Multi-Stage Centrifugal Compressors, Xiaomo Jiang, Jigang Meng, Huaiyu Hui, Wenqing Meng, Haibin Yang, Huize Chen

Journal of System Simulation

Abstract: To address the challenges of insufficient real-time monitoring capability and weak coupling between physical entities and virtual models in the long-term safe and reliable operation of multi-stage centrifugal compressors under complex operating conditions, this paper proposes a digital twin construction method based on data-model fusion for intelligent health monitoring. A unit-system-component hierarchical virtual twin model is established to achieve the coordinated mapping of geometric structure, operational behavior, and monitoring data of the compressor. By integrating a terminal-edge-cloud collaborative architecture, data-driven models are dynamically coupled with the virtual twin to construct a digital twin-based health monitoring platform, enabling operating state …

Design Of A Simulation Dataset For Fine-Grained Detection Of Space Target Sequence Images, Shiyan Wang, Danpu Zhao, Haikun Hong

Journal of System Simulation

Abstract:

With the increasing number of space objects such as satellites, there is a growing need for fine-grained detection and recognition of distant space targets. However, obtaining real observational data remains difficult due to high costs and insufficient annotation detail. To overcome these limitations, asynthetic dataset generation system based on multi-module collaboration is developed. Using joint simulation with STK and Blender, the proposed system simulates optical imaging conditions of space targets and automatically produces sequential images along with corresponding fine-grained labels. A large-scale simulation dataset is constructed for fine-grained detection in space target image sequences. It contains …

Robotic Digital Twin Modeling Method Integrating Mbse And Modelica, Zaiwu Mei, Jiangman Zhou, Cong Zhang, Yiping Gao, Zerun Zhu

Journal of System Simulation

Abstract: To address the issues of disconnection between system architecture design and dynamic simulation, as well as the limited reusability and scalability of models in robotic digital twin modeling, a modular modeling approach integrating MBSE (model-based systems engineering) and Modelica is proposed. The method employs MBSE for system architecture design and requirement traceability, and combines Modelica for multi-domain dynamic simulation, forming a full-chain digital twin model from system design to physical behavior simulation. Standardized interfaces and a generic component model library are developed to decouple and integrate mechanical, electrical, and control subsystems, enabling rapid model assembly and functional expansion. A …

Modeling And Simulation Of Multi-Hop Routing In 3d Tunnel Wireless Sensor Networks, Fang Cao, Jiguang Yang, Jiuyuan Huo

Journal of System Simulation

Abstract: To address the unbalanced energy consumption and short network lifetime caused by the complex topology and strong energy coupling of three-dimensional tunnel wireless sensor networks, this study constructs a system-level operating model integrating spatial topology, energy evolution, and routing decision-making, and proposes an energy management for balanced and efficient routing (EMBER) algorithm based on the competition of tribes and cooperation of members (CTCM) algorithm. The optimal number of cluster heads is derived through tunnel spatial modeling. Clustering is performed using a Gaussian mixture model optimized by CTCM, and efficient cluster-head selection is achieved by combining data envelopment analysis. An …

Rrt*-Based Robotic Manipulator Path Planning With Artificial Potential Field Guidance And Accumulator-Based Adaptive Adjustment, Fangzheng Gao, Xu Guo, Quan Sun, Jiacai Huang, Zhongcai Zhang

Journal of System Simulation

Abstract: To address the problems of blind sampling, slow convergence, and path redundancy in robotic manipulator path planning in cluttered and unstructured three-dimensional environments, An RRT* algorithm integrating artificial potential field guidance and accumulator-based adaptive adjustment, namely APGA-RRT* (artificial potential field guidance and accumulator adaptive adjustment-RRT*). The proposed algorithm improves the overall planning performance from three aspects: sampling, expansion, and path optimization. In the sampling stage, a potential-field-guided sampling strategy based on target-distance weighting and virtual-target switching is constructed, obstacle suppression and safe-distance gating mechanisms are incorporated to dynamically adjust the guidance intensity, thereby enhancing target directivity and local escape …

Online Fine-Tuning Of Binocular Camera Extrinsic Parameters Based On Position-Iteration Dual Perception, Qian Long, Tuerhong Dilixiati, Qi Zheng, Lijun Shen

Journal of System Simulation

Abstract: In long-term operation of binocular systems, small drifts in extrinsic parameters may occur due to temperature changes, vibration, and mechanical shocks. As these drifts accumulate, the ranging error increases with distance and seriously degrades long-range measurement performance. Because online compensation is difficult, such small drifts are often neglected. To address this problem, an online fine-tuning method based on position-iteration dual perception is proposed. A multiplicative coupling weighting model is established by integrating spatial reliability with an iteration-stage modulation function. A three-stage progressive optimization algorithm is designed to balance convergence speed and robustness. A simulation framework for offline calibration and …

Review Of Evaluation Metrics For The Credibility Of Autonomous Driving Test Scenarios, Jiwei Li, Runmin Wang, Yu Zhu, Jingjun Cheng, Xiangmo Zhao

Journal of System Simulation

Abstract: Currently, scenario-based simulation testing has become a core technical approach for verifying autonomous driving system functionality. However, due to the absence of unified evaluation standards for simulation scenarios, significant differences exist among the metrics constructed and adopted by different studies, each with its own limitations. This hinders mutual recognition of research outcomes and prevents scientific measurement of scenario quality. This study systematically reviews relevant research from the past five years, categorizing autonomous driving test scenarios into four types: parameter-descriptive, trajectory-driven, environment-simulation, and perception-data-driven. It clarifies the core characteristics, application objectives, and generation mechanisms of each scenario type. Subsequently, focusing …

Hybrid Attention For Low-Overlap Point Cloud Registration, Huaijun Wang, Zonghua Yu, Chenxin Xu, Junhuai Li, Chenzhi Li, Junjie Yin

Journal of System Simulation

Abstract: To address the significant registration errors caused by large initial pose deviations in low overlap ratio point cloud, this paper presents a two-stage optimization method that integrates selfattention and cross-attention mechanisms. Orientation feature representation is enhanced using equivariant self-attention, semantic alignment is achieved through invariant cross-attention, and rotational equivariance is modeled with an octahedral group for coarse registration. Various attention variants are employed to aggregate features along the anchor dimension, and a local-to-global module is utilized for fine registration. On the 3DLoMatch dataset, the proposed method achieves a registration recall of 77.0% and an inlier ratio of 44.3%. Even …

Numerical Simulation Study On Flow-Induced Vibration Energy Harvesting Characteristics Of Piezoelectric Energy Harvester With Elliptical Cylinder Bluff-Body, Jiechao Lei, Long Li, Ji Yao

Journal of System Simulation

Abstract: To improve the self-powering efficiency of miniature internet of things devices, this paper establishes a fluid-structure-electric multi-field coupled computational fluid dynamics (CFD) model based on the ANSYS Fluent platform. It conducts a numerical simulation study on the flow-induced vibration energy harvesting characteristics of a piezoelectric cantilever beam energy harvester with an elliptical cylinder bluff-body. A systematic analysis is performed on the influence mechanism of flow velocity within the range of 0.1~0.5 m/s on the output power. The results indicate that the output power of the harvester exhibits phased growth with increasing flow velocity. In the range below 0.15 m/s, …

Breaking The Build: Detecting Software Supply Chain Vulnerabilities In Ci/Cd Pipelines, Mercedes R. Wahl, Dr. Benjamin Yankson

Military Cyber Affairs

This study examines whether integrating structured DevSec- Ops security controls into CI/CD pipelines can reduce software supply chain risk by preventing vulnerable components from progressing through the software development lifecycle. Software supply chain attacks frequently originate from weaknesses or compromises within dependencies, build environments, and trusted development stages, making early detection essential. A controlled sandbox experiment compared two pipeline configurations: a baseline CI/CD pipeline with no automated security enforcement and a secure DevSecOps pipeline integrating automated vulnerability scanning, SBOM generation, and artifact integrity verification. A known vulnerable dependency, the Python requests package (version 2.19.0) associated with CVE-2018-18074, was intentionally introduced …

Mitigating Common Vulnerabilities And Exposures In Cobol-Based Critical Systems Using The Strangler-Fig Pattern, Lauren E. Caruso, Vincent J. Compeau, Assefaw H. Gebremedhin

Military Cyber Affairs

COBOL-based legacy systems continue to underpin critical infrastructure in banking and government sectors despite their age and associated cybersecurity risks. Originally developed through a Department of Defense–sponsored initiative to standardize business computing, COBOL remains widely used in mission-critical environments. However, these systems face increasing vulnerabilities due to outdated security architectures, workforce shortages, and rising maintenance costs. This paper examines cybersecurity and operational challenges associated with COBOL systems and evaluates the Strangler Fig pattern as a modernization strategy that enables incremental replacement while maintaining continuity. The findings highlight implications for financial institutions and public-sector organizations dependent on legacy infrastructure.

Hybrid Deep (Cnn-Bilstm) Intrusion Detection For Defense And Mission-Critical Networks, Corey A Cheng, Jermaine Anim-Addo, Asma Jakir Hussain, Zion O Smith-Fox, Sanjay Goel, Yuksel Celik

Military Cyber Affairs

This article examines how hybrid deep learning can strengthen intrusion detection for military and defense networks. Using the CSE-CIC-IDS2018 dataset, the study evaluates a CNN-BiLSTM model designed to detect benign traffic and multiple attack categories, including DDoS, DoS, botnet, brute-force, web attack, and infiltration activity. The model achieved strong multi-class detection performance, with 0.9893 accuracy and 0.9979 ROC-AUC. The findings suggest that AI-supported intrusion detection can improve cyber defense operations, analyst triage, and protection of mission-critical networks.

Foreward, Todd Arnold

Military Cyber Affairs

No abstract provided.

Letter From The Director: Mastery In Practice, Joseph Schafer

Military Cyber Affairs

No abstract provided.

Degree Assortativity And Estimation Of Degree Distribution In A Contact Network Of People Who Inject Drugs, Peter Geissert

Dissertations and Theses

This dissertation analyzes data from a respondent driven sampling (RDS) study of people who inject drugs in Portland, OR.  The objective was to assess assumptions for the use of weighted estimators to estimate a population physical contact (syringe sharing) network degree distribution.

Visualization of degree distribution for social and physical networks, Kolmogorov-Smirnov tests of difference, and kernel tests of equivalence were used for comparison of distributions. Spearman's rho and GAM non-parametric regression models were used to test for association and assess non-monotonic relationship. The validity of Markov chain assumptions for RDS was assessed using a transition matrix, Markov chain graphs, …

Spatial Markov Equilibrium Models For Taxi Services: Driver Decision, Search Friction, And Locational Pricing, Yanchao Liu

Industrial and Systems Engineering Faculty Research Publications

This paper develops a modeling framework for stochastic multi-agent systems and applies it to equilibrium and pricing analysis in urban taxi markets. Travel demand is represented as a trip network and embedded in a Markov chain that captures both locational and in transit taxi states, with transition dynamics reflecting trip durations, search frictions, spatial competition, and drivers’ perceptions of long-term value. The framework features a parametric Markov chain with endogenous transition probabilities and a behavioral model in which agents’ decisions depend on anticipated long-term rewards. We establish equilibrium existence and examine two locational pricing schemes that align individual incentives with …

Spatial Reconstructability Analysis: Information-Theoretic Modeling Of Categorical Raster Data, David Percy

Dissertations and Theses

This research focuses on the application of Reconstructability Analysis (RA), an information-theoretic machine learning (ML) methodology, to categorical spatial data in Geographic Information Systems (GIS). RA was developed in the systems community with applications including classification, prediction, pattern recognition, and decision analysis. RA is implemented in OCCAM (Organizational Complexity Computation and Modeling), a software suite developed at Portland State University that analyzes discrete data in tabular form, with observations in rows and variables in columns. While RA has been successfully applied to a variety of domains, no systematic application to georeferenced raster data arranged in regular grids has been previously …

Structured And Interpretable Representations For Ensemble And Dynamical Systems, Yuan-Hung Kuan

McKelvey School of Engineering Graduate Student Theses & Dissertations

Precise and robust manipulation of large populations of structurally identical dynamical systems with heterogeneous dynamics, known as ensemble systems, is a central challenge in many emerging applications. These systems are often difficult to analyze and control because of the inherent nonlinearities, high dimensionality, heterogeneity, and incomplete knowledge of the underlying dynamics. To address these challenges, this thesis develops structured and interpretable representations for the analysis, control, and learning of nonlinear ensemble systems. Its central objective is to transform complex heterogeneous dynamics into representations that preserve essential structural and dynamical properties while enabling tractable computation and effective control design. First, the …

The Self-Aware Room: A Framework For Operational Self-Awareness In Evolvable Blended Environments, David B. Smith

Publications and Research

The Self-Aware Room (SAR) is a room-scale research environment developed within the larger Balanced Blended Space and Blended Reality Performance System research trajectory. Rather than treating the room as a conventional “smart” environment composed of fixed automation technologies, SAR approaches it as an evolvable blended environment made from physical, virtual, conceptual, sensory, computational, and performative relationships. Its defining feature is not any particular sensor, model, or output device, but the set of transformations through which physical activity becomes structured observation, bounded representation, interpreted state, governed decision, and mediated response.

This paper develops the conceptual and methodological foundations of SAR as …

Supply Chain Analysis: The Oregonator Autocatalytic Case Study, Abigail Butcher

Discovery Day - Daytona Beach

Understanding stability in complex supply chains remains a critical challenge due to nonlinear feedback, delayed responses, and sensitivity to parameter changes. This project presents a novel framework that applies bifurcation analysis to evaluate system stability, using the Oregonator autocatalytic chemical reaction model as an analog for supply chain dynamics. A parameter sweep of key model variables, particularly the stoichiometric factor f and the reaction rate constants k, is used to identify transitions between stable and oscillatory regimes. These transitions provide insight into how variations in feedback strength can drive instability in real-world systems. The framework will then be extended to …

Honeybee-Inspired Swarm Intelligence For Autonomous Adaptability Of Martian Infrastructure, Morgan Kendall

Discovery Day - Daytona Beach

Current research in autonomous space systems primarily relies on centralized control or swarm methods designed for fixed mission scenarios. These approaches lack the flexibility needed for long-duration Mars operations, where infrastructure must adapt to changing conditions, evolving mission goals, and limited human oversight. This creates a critical gap in developing autonomous systems capable of continuous self-organization. This gap is being addressed by developing a biologically inspired, adaptive Martian infrastructure using swarm intelligence. The scope includes key system domains such as power distribution, communication networks, and surface logistics. Agent-based modeling software will simulate infrastructure components as autonomous agents that evaluate local …

Designing Under Pressure: A Comparative Study Of Ai And Manual Interface Development In A Naval Weapon System Scenario, Tsimur Babakhanau, Noah Clark, Colby Keller, Mary Grace Sorenson, Zoe Tiede

Discovery Day - Daytona Beach

This study implements a detailed naval scenario in which participants acted as operators on a Navy destroyer equipped with a Laser Weapon System (LaWS). Their task was to create a dashboard capable of stopping incoming suicide drone swarms while managing critical laser functions such as thermal constraints, threat prioritization, and adapting to attack dynamics. Poor management could leave the ship vulnerable. AI is increasingly integrated into design methods, fundamentally transforming the process of building user interfaces by compressing hours of work into minutes. Although AI design tools are becoming more common, little is known about how well beginners can use …

Functionality Risk Assessment And Risk-Based Management For Critical Infrastructure Systems, Anteneh Zewdu Deriba

Dissertations and Theses

Critical infrastructure systems such as transportation networks serve as the lifelines of modern society, supporting economic activity and ensuring access to critical services. Their disruption under extreme events can produce consequences extending far beyond physical damage to individual assets. In transportation networks for instance, failures of critical assets such as bridges and tunnels can reduce accessibility of communities, limit freight capabilities for commerce, and increase travel distance and travel time of road users. These consequences associated with the system functionality loss are tied not only to the physical vulnerability and failure of individual assets, but also to the system configuration …

Balancing Innovation And Integrity: Ethical Implications Of Ai Use In Higher Education, Petronella Muziti, Ntando S. Sibanda

African Conference on Information Systems and Technology

Artificial intelligence (AI) is rapidly transforming higher education, creating opportunities while raising ethical concerns such as bias, privacy violations, academic misconduct and reduced human-centred teaching. This study examined how institutions can balance AI innovation with academic integrity and equity, focusing on lecturers’ ethical dilemmas and institutional readiness. A triangulation design incorporating quantitative and qualitative methods was used. Twelve semi-structured interviews and two focus group discussions involving eighteen participants were conducted across five universities, while 150 questionnaires were distributed, yielding 128 valid responses. Descriptive statistics and thematic analysis were applied. Findings showed that lecturers reported student misuse and plagiarism (78%), AI …