System Phasing And Schedule Growth Analysis,
2022
Air Force Institute of Technology
System Phasing And Schedule Growth Analysis, Daniel A. Long
Theses and Dissertations
Software development research, once a priority for the DoD, has received less focus in recent years. What research that has occurred has focused on size and cost prediction of software. Generally lacking in these studies is analysis on phase distributions and schedule. Putnam (1978) showed that there were measurable effects between early program management and final schedule growth, but these relationships have not been explored using the 2001-2021 DoD Software Resources Data Report (SRDR) database. Additionally, industry software development guidance provides rules of thumb for effort allocation, but a comparison of the rules to DoD software projects is nonexistent. This …
Life Cycle Analysis Of Hydrogen Fuel Derived From Aluminum Versus Diesel,
2022
Air Force Institute of Technology
Life Cycle Analysis Of Hydrogen Fuel Derived From Aluminum Versus Diesel, Tyson S. Metlen
Theses and Dissertations
The Department of Defense needs energy sources beyond petroleum products to effectively combat area denial strategies employed by its adversaries. Petroleum fuels are expensive, they have deleterious environmental impacts, and most of the world’s oil reservoirs are in volatile countries. A proposed alternative energy carrier is reacting aluminum with water to produce hydrogen and using the hydrogen as a fuel source. Normally aluminum forms a protective oxide layer that prevents continuous reaction but if aluminum is mixed with a 3.5% by weight gallium-indium eutectic, the oxide layer cannot form, and the reaction is sustainable. This study conducts a life cycle …
Exploring The Value Of Training System Alternatives Through Methods Technologies, And Relevant Attributes,
2022
Air Force Institute of Technology
Exploring The Value Of Training System Alternatives Through Methods Technologies, And Relevant Attributes, Brian R. Novitsky
Theses and Dissertations
Skilled maintainers are being lost at a higher rate than average of all enlisted career fields within the Air Force. Although incentive programs can provide some retention, attrition rates may continue to vary, placing the readiness of the warfighter in jeopardy. Additionally, the technologies used to train maintainers have evolved substantially, including augmented reality (AR) and virtual reality (VR) solutions, among others. These technologies have recently gained notoriety as novel ways to increase training effectiveness, providing avenues for maintainers to achieve greater skill levels at a faster rate than traditional platforms. Through semi-structured subject matter expert (SME) interviews, this qualitative …
Simulating Autonomous Cruise Missile Swarm Behaviors In An Anti-Access Area Denial (A2ad) Environment,
2022
Air Force Institute of Technology
Simulating Autonomous Cruise Missile Swarm Behaviors In An Anti-Access Area Denial (A2ad) Environment, Kyle W. Goggins
Theses and Dissertations
The increasingly sophisticated anti-access area denial (A2AD) threat imposed by the modern integrated air defense system (IADS), coupled with the decreasingly potent advantage provided by high-end stealth platforms, has prompted Air Force senior leaders to invest in radically changing the nature of air power for the year 2030 and beyond. A prominent element of this new vision is weapon swarming, which aims to address this challenge by overwhelming the IADS with huge numbers of low-cost, attritable aerial assets emboldened by autonomous capabilities. This research proposes a framework for classifying the different levels of autonomous capability along three independent dimensions—namely ability …
Screening Heuristics For The Evaluation Of Covert Network Node Insertion Scenarios,
2022
Air Force Institute of Technology
Screening Heuristics For The Evaluation Of Covert Network Node Insertion Scenarios, Andrew E. Pekarek
Theses and Dissertations
The majority of research on covert networks uses social network analysis (SNA) to determine critical members of the network to either kill or capture for the purpose of network destabilization. This thesis takes the opposite approach and evaluates potential scenarios for inserting an agent into a covert network for information gathering purposes or future disruption operations. Due to the substantial number of potential insertion scenarios in a large network, this research proposes three screening heuristics that leverage SNA measures to reduce the solution space before applying a simple search heuristic.
The Impact Of Ride-Hail Surge Factors On Taxi Bookings,
2022
National University of Singapore
The Impact Of Ride-Hail Surge Factors On Taxi Bookings, Sumit Agarwal, Ben Charoenwong, Shih-Fen Cheng, Jussi Keppo
Research Collection School Of Computing and Information Systems
We study the role of ride-hailing surge factors on the allocative efficiency of taxis by combining a reduced-form estimation with structural analyses using machine-learning-based demand predictions. Where other research study the effect of entry on incumbent taxis, we use higher frequency granular data to study how location-time-specific surge factors affect taxi bookings to bound the effect of customer decisions while accounting for various confounding variables. We find that even in a unique market like Singapore, where incumbent taxi companies have app-based booking systems similar to those from ride-hailing companies like Uber, the estimated upper bound on the cross-platform substitution between …
Stochastic Knapsack Revisited: The Service Level Perspective,
2022
Singapore Management University
Stochastic Knapsack Revisited: The Service Level Perspective, Guodong Lyu, Mabel C. Chou, Chung-Piaw Teo, Zhichao Zheng, Yuanguang Zhong
Research Collection Lee Kong Chian School Of Business
A key challenge in the resource allocation problem is to find near-optimal policies to serve different customers with random demands/revenues, using a fixed pool of capacity (properly configured). In this paper, we study the properties of three classes of allocation policies-responsive (with perfect hindsight), adaptive (with information updates), and anticipative (with forecast information) policies. These policies differ in how the information on actual demand and revenue of each customer is being revealed and integrated into the allocation decisions. We show that the analysis of these policies can be unified through the notion of "persistency" (or service level) values-the probability that …
Hybrid Tabu Search Algorithm For Unrelated Parallel Machine Scheduling In Semiconductor Fabs With Setup Times, Job Release, And Expired Times,
2022
Singapore Management University
Hybrid Tabu Search Algorithm For Unrelated Parallel Machine Scheduling In Semiconductor Fabs With Setup Times, Job Release, And Expired Times, Changyu Chen, Madhi Fathi, Marzieh Khakifirooz, Kan Wu
Research Collection School Of Computing and Information Systems
This research is motivated by a scheduling problem arising in the ion implantation process of wafer fabrication. The ion implementation scheduling problem is modeled as an unrelated parallel machine scheduling (UPMS) problem with sequence-dependent setup times that are subject to job release time and expiration time of allowing a job to be processed on a specific machine, defined as: R|rj,eij,STsd|Cmax. The objective is first to maximize the number of processed jobs, then minimize the maximum completion time (makespan), and finally minimize the maximum completion times of the non-bottleneck machines. A mixed-integer programming (MIP) model is proposed as a solution approach …
Coordinated Delivery To Shopping Malls With Limited Docking Capacity,
2022
Tsinghua University
Coordinated Delivery To Shopping Malls With Limited Docking Capacity, Ruidian Song, Hoong Chuin Lau, Xue Luo, Lei Zhao
Research Collection School Of Computing and Information Systems
Shopping malls are densely located in major cities such as Singapore and Hong Kong. Tenants in these shopping malls generate a large number of freight orders to their contracted logistics service providers, who independently plan their own delivery schedules. These uncoordinated deliveries and limited docking capacity jointly cause congestion at the shopping malls. A delivery coordination platform centrally plans the vehicle routes for the logistics service providers and simultaneously schedules the dock time slots at the shopping malls for the delivery orders. Vehicle routing and dock scheduling decisions need to be made jointly against the backdrop of travel time and …
Advancing Ubiquitous Collaboration For Telehealth - A Framework To Evaluate Technology-Mediated Collaborative Workflow For Telehealth, Hypertension Exam Workflow Study,
2022
Rochester Institute of Technology
Advancing Ubiquitous Collaboration For Telehealth - A Framework To Evaluate Technology-Mediated Collaborative Workflow For Telehealth, Hypertension Exam Workflow Study, Christopher Bondy Ph.D., Linlin Chen Ph.D, Pamela Grover Md, Pengcheng Shi Ph.D
Articles
Healthcare systems are under siege globally regarding technology adoption; the recent pandemic has only magnified the issues. Providers and patients alike look to new enabling technologies to establish real-time connectivity and capability for a growing range of remote telehealth solutions. The migration to new technology is not as seamless as clinicians and patients would like since the new workflows pose new responsibilities and barriers to adoption across the telehealth ecosystem. Technology-mediated workflows (integrated software and personal medical devices) are increasingly important in patient-centered healthcare; software-intense systems will become integral in prescribed treatment plans [1]. My research explored the path to …
Research On Nonlinear Evaluation Method Of Situational Hot Spots,
2022
College of Command and Control Engineering, Army Engineering University of PLA, Nanjing 210007, China;
Research On Nonlinear Evaluation Method Of Situational Hot Spots, Tengjiao Mao, Dongge Zhang, Xuefeng Liang, Yanjie Niu, Minggang Yu, Ming He
Journal of System Simulation
Abstract: The excessive amount of data and information in the situation map is likely to produce a huge cognitive load that exceeds the physiological limit. This can lead to delays in the perception, judgment, and decision-making of the commander, or even failure of decision-making activities in severe cases. For this reason, situation information needs to be processed to assess and highlight situational hotspots so that cognitive overload can be tackled. Based on the aggregation factors of collaborative targets, this paper takes the effective impact possibility of situational targets and the collaboration as the indicators, derives the attention function, and designs …
Review Of System Of Systems Combat Effectiveness Evaluation And Optimization Methods,
2022
1.Military Exercise and Training Center, Army Academy of Armored Forces, Beijing 100072, China;2.Unit 32128 of PLA, Jinan 250024, China;
Review Of System Of Systems Combat Effectiveness Evaluation And Optimization Methods, Ziwei Zhang, Qisheng Guo, Zhiming Dong, Ang Gao, Yifei Wang
Journal of System Simulation
Abstract: The characteristics of system-of-systems combat effectiveness evaluation and optimization are analyzed. In light of the "holism", this paper proposes an idea of dividing system of systems combat effectiveness evaluation and optimization into three stages of comprehensive evaluation, analysis, and optimization. As for the practical problems that need to be solved in the three stages, typical methods suitable for each stage are summarized.The advantages and disadvantages of different methods are then compared. In view of the practical difficulties in implementing system of systems combat effectiveness evaluation and optimization guided by the "holism", this paper puts forward the next research directions …
Zoomfft-Based Demodulation Algorithm For Underwater Acoustic Ofdm Signals,
2022
1.School of Electronic Engineering and Automation, Guilin University of Electronic Technology, Guilin 541004, China;2.Guangxi Key Laboratory of Automatic Detection Technology and Instruments, Guilin 541004, China;
Zoomfft-Based Demodulation Algorithm For Underwater Acoustic Ofdm Signals, Qing Guo, Angdi Li, Jing Wu, Haitao Su
Journal of System Simulation
Abstract: The picket fence effect of fast Fourier transform (FFT) restricts the demodulation performance of the underwater acoustic(UWA) communication systemusing orthogonal frequency division multiplexing (OFDM). To solve this problem, we propose a demodulation algorithm based on ZoomFFT. Specifically, the received signal is processed by frequency shifting and downsampling forarefined spectrum, which improves the spectralresolution and weakens the picketfence effect.Meanwhile, the channel response is refined, and the channel equalization algorithm is constructed on the basis of the minimum mean square error (MMSE) principle to eliminate the channel influence. Simulations show that the performance of underwater acoustic OFDM demodulation algorithm based on …
Research On Design Method For Transfer Function Of Dc/Dc Converter System Based On Frequency Domain Method,
2022
School of Mechanical and Electrical Engineering, Chengdu University of Technology, Chengdu 610059, China;
Research On Design Method For Transfer Function Of Dc/Dc Converter System Based On Frequency Domain Method, Song Gao, Xue Yin, Jiantao Xu, Yuhao Miao
Journal of System Simulation
Abstract: A robust optimal synchronization control method based on coupling dynamics model of the H-type motion platform is proposed for the problem that the H-type motion platform driven directly by permanent magnet linear synchronous motor has uncertainties such as biaxial coupling, parameter perturbation and external disturbances, which affect the synchronization control accuracy and robustness of the system. A biaxial coupling dynamics model is established based on Euler-Lagrange equation. The cross coupling synchronization controller is designed to effectively combine the single-axis tracking error with the biaxial synchronization error and its rate of change. TheH∞robust optimal synchronous controller …
Modeling & Simulation Based System Of Systems Engineering,
2022
1.Beihang University, Beijing, 100191, China;2.Engineering Research Center of Complex Product Advanced Manufacturing System, Ministry of Education, Beijing, 100191, China;
Modeling & Simulation Based System Of Systems Engineering, Lin Zhang, Kunyu Wang, Yuanjun Laili, Lei Ren
Journal of System Simulation
Abstract: To accommodate the dark and unstructured underwater working environment, the near-body pressure distribution characteristics of a bionic robot fish undulating in near wall region is studied. The feasibility of using artificial lateral line(ALL) to estimate the wall effect and flow field parameters is analyzed theoretically. A CFD(computational fluid dynamics) coupled solution model for near-body pressure simulation of a bionic robotic fish swimming near the wall is established and a near-body pressure data extraction and processing method is proposed. The effect of the wall clearance, inlet flow velocity and strouhal number (St) on the fish near-body pressure distribution …
Constructing The Agent Discrete Simulation Based On Devs Atomic Model,
2022
1.Beihang University, Beijing 100191, China;2.Engineering Research Center of Complex Product Advanced Manufacturing Systems, Ministry of Education, Beijing 100191, China;
Constructing The Agent Discrete Simulation Based On Devs Atomic Model, Xiaohan Wang, Lin Zhang, Yuanjun Laili, Kunyu Xie, Tingchun Hu
Journal of System Simulation
Abstract: In order to resolve the nonlinear and ill-posed inverse problem of the image reconstruction of electrical capacitance tomography (ECT), an image reconstruction algorithm based on one-dimensional convolutional neural network (1D CNN) is presented. The nonlinear mapping relationship between the independent measurement value of ECT system and the gray value of reconstructed image is established by 1D CNN. Six typical flow regimes with random distribution are obtained by the finite element simulation software and a 1D CNN is successfully trained. Simulation and static experiments are carried out and the reconstructed images using linear back projection, Landweber iterative algorithm and 1D …
Vehicle Routing Problem With Refined Oil Secondary Distribution Considering Workload Balance,
2022
1.School of Information, Beijing Wuzi University, Beijing 101149, China;
Vehicle Routing Problem With Refined Oil Secondary Distribution Considering Workload Balance, Zhenping Li, Guang Yang, Qianqian Han
Journal of System Simulation
Abstract: The small-signal model of a DC/DC converter is usually built by the analytic method, and its accuracy is verified by the frequency domain method. A new idea is developed to model the small signal of the converter, i.e., directly using the frequency domain method.The design process is as follows: The principle and modeling mechanism of the frequency domain method are analyzed, and the realization flow of Matlab modeling is introduced. A typical phase-shifted full-bridge converter is taken as the design object, and a simulation model is built by Simulink. The transfer function is obtained on the basis of …
Lod Modeling Method For Three-Dimensional Objects With Energy Operator,
2022
1.School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China;
Lod Modeling Method For Three-Dimensional Objects With Energy Operator, Yongzhi Wang, Zhenchao Li, Pengyu Liu, Hui Wang
Journal of System Simulation
Abstract: Current level of detail (LOD) modeling methods do not combine simplification and subdivision, which results in models not being rich in detail level. Therefore, the energy operator was used to combine the simplification algorithm of a three-dimensional (3D) object model with the subdivision algorithm, and a LOD modeling method based on an energy operator was proposed for 3D objects. The method involves three major steps: calculation of energy operators for 3D models, model simplification and model subdivision based on an energy operator. Experiments show that this method can generate models with rich levels of detail and has good visualization …
Research On Semantic Segmentation Of Natural Landform Based On Edge Detection Module,
2022
School of Mechanical Engineering, Hebei University of Technology, Tianjin 300130, China;
Research On Semantic Segmentation Of Natural Landform Based On Edge Detection Module, Qizong Shen, Chunyan Gao
Journal of System Simulation
Abstract: To classify pixels of natural landform edges in remote sensing images, this paper proposes a multi-channel fusion model and a decoder-side module model both integrating an edge detection module. The edge detection module takes the Canny operator as the base to perform closed operations and mean filtering, as a result of which accurate image edges can be achieved. Based on DeepLabV3+, the semantic segmentation network is connected with an edge planning module in parallel at encoder and decoder sides respectively. The experimental results show that the two improved networks can achieve a better segmentation effect on a high-resolution natural …
Energy Consumption Prediction For Air-Conditioning System Based On Dynamic Temperature Control,
2022
School of Science, Xi'an University of Architecture and Technology, Xi'an, 710055, China;
Energy Consumption Prediction For Air-Conditioning System Based On Dynamic Temperature Control, Yan Bai, Lulu Wu, Yin'e He, Yuying Wang
Journal of System Simulation
Abstract: To solve the problem of energy consumption prediction for air-conditioning systems implementing dynamic temperature control, we designed a dynamic temperature control strategy and obtained a dataset on the hourly energy consumption of the air-conditioning system through EnergyPlus simulation. An improved particle swarm optimization-back propagation neural network (IPSO-BPNN) prediction model was built on the basis of energy consumption analysis by an integrated method. Clustering, classification, and correlation analysis methods were integrated to mine the energy consumption pattern of the air-conditioning system and determine the input variables for the prediction model. A nonlinear change strategy was designed to adjust the inertia …
