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Examining How Standby Assets Impact Optimal Dispatching Decisions Within A Military Medical Evacuation System Via A Markov Decision Process Model, Kylie Wooten 2021 Air Force Institute of Technology

Examining How Standby Assets Impact Optimal Dispatching Decisions Within A Military Medical Evacuation System Via A Markov Decision Process Model, Kylie Wooten

Theses and Dissertations

The Army medical evacuation (MEDEVAC) system ensures proper medical treatment is readily available to wounded soldiers on the battlefield. The objective of this research is to determine which MEDEVAC unit to task to an incoming 9-line MEDEVAC request and where to station a single standby unit to maximize patient survivability. A discounted, infinite-horizon continuous-time Markov decision process model is formulated to examine this problem. We design, develop, and test an approximate dynamic programming (ADP) technique that leverages a least squares policy evaluation value function approximation scheme within an approximate policy iteration algorithmic framework to solve practical-sized problem instances. A computational …


Stochastic Programming Design For West Africa Logistics Networks, Julius C. Walker 2021 Air Force Institute of Technology

Stochastic Programming Design For West Africa Logistics Networks, Julius C. Walker

Theses and Dissertations

The USAFRICOM is studying methods to increase the resiliency of its West African Logistic Network, a hub-and-spoke network design responsible for sustaining long term humanitarian and security missions in the West Africa region. This paper employs a two-stage stochastic programming network design modeled on the WALN that builds a flexible supply chain capable of responding to periodic disruptions while maintaining peak resiliency. Elements such as cost, probability, and event-based disruption are integrated into the model to mirror challenges the WALN faces. We demonstrate that incorporating resilient based response mechanism provide a 90% reduction in cost compared to meeting the logistical …


A Simulation Modeling The Effects Of Maintenance Personnel On Aircraft Sortie Generation, Benjamin D. Huffman 2021 Air Force Institute of Technology

A Simulation Modeling The Effects Of Maintenance Personnel On Aircraft Sortie Generation, Benjamin D. Huffman

Theses and Dissertations

Commanders and wargamers lack adequate tools to quickly determine the number of mission-capable (MC) aircraft and number of achievable sorties to support wargames and exercises. Even less understood is the impact of available maintenance personnel on sortie generation. The Expected-Number-of-In-Game-Mission-capable Aircraft (ENIGMA) simulation was recently developed to calculate the number of MC aircraft and number of sorties own accounting for the number and type of aircraft, scheduled sorties, mean-time-between-failure (MTBF), and mean-time-to-repair (MTTR). ENIGMA is extended by replacing the MTTR input with functions derived from actual numbers and types of maintenance personnel available. Functions in the form of response surface …


The Impact Of Threat Levels At The Casualty Collection Point On Military Medical Evacuation System Performance, Nathaniel C. Dennie 2021 Air Force Institute of Technology

The Impact Of Threat Levels At The Casualty Collection Point On Military Medical Evacuation System Performance, Nathaniel C. Dennie

Theses and Dissertations

One of the primary duties of the Military Health System is to provide effective and efficient medical evacuation (MEDEVAC) to injured battlefield personnel. To accomplish this, military medical planners seek to develop high-quality dispatching policies that dictate how deployed MEDEVAC assets are utilized throughout combat operations. This thesis seeks to determine dispatching policies that improve the performance of the MEDEVAC system. A discounted, infinite-horizon continuous-time Markov decision process (MDP) model is developed to examine the MEDEVAC dispatching problem. The model incorporates problem features that are not considered under the current dispatching policy (e.g., myopic policy), which tasks the closest-available MEDEVAC …


Ccsfs/Ksc Total Lightning Warning Radii Optimization For Merlin Using Preexisting Lightning Areas, Kimberly G. Holland 2021 Air Force Institute of Technology

Ccsfs/Ksc Total Lightning Warning Radii Optimization For Merlin Using Preexisting Lightning Areas, Kimberly G. Holland

Theses and Dissertations

The purpose of this research is to optimize lightning warning radii specifications for the 45th Space Wing (45 SW), thus reducing the number of unnecessary warnings that delay ground processing needed for space launch execution at Kennedy Space Center and Cape Canaveral Space Force Station. This thesis sought to answer two key research questions addressing: 1) What radius reduction effectively balances both safety and operations and do reduction recommendations from previous research align with results from the new detection system? 2) What insights can be gained from comparing measurement results for seasonal lightning events as well as lightning types? This …


Automated Sentiment Analysis For Personnel Survey Data In The Us Air Force Context, Julia M. Haines 2021 Air Force Institute of Technology

Automated Sentiment Analysis For Personnel Survey Data In The Us Air Force Context, Julia M. Haines

Theses and Dissertations

When surveys are distributed across the Air Force (AF), whether it be an employee engagement survey, a climate survey, or similar, significant resources are put towards the development, distribution and analysis of the survey. However, when open ended questions are included on these surveys, respondent comments are generally underutilized, more often treated as a source for pull-quotes rather than a data source in and of themselves. This is due to a lack of transparency and confidence in the accuracy of machine-aided methods such as sentiment analysis and topic modeling. This confidence reduces further when the text has special context, such …


The Autonomous Attack Aviation Problem, John C. Goodwill 2021 Air Force Institute of Technology

The Autonomous Attack Aviation Problem, John C. Goodwill

Theses and Dissertations

An autonomous unmanned combat aerial vehicle (AUCAV) performing an air-to-ground attack mission must make sequential targeting and routing decisions under uncertainty. We formulate a Markov decision process model of this autonomous attack aviation problem (A3P) and solve it using an approximate dynamic programming (ADP) approach. We develop an approximate policy iteration algorithm that implements a least squares temporal difference learning mechanism to solve the A3P. Basis functions are developed and tested for application within the ADP algorithm. The ADP policy is compared to a benchmark policy, the DROP policy, which is determined by repeatedly solving a deterministic orienteering problem as …


Bayesian Augmentation Of Cnn-Lstm For Video Classification With Uncertainty Measures, Emmie K. Swize 2021 Air Force Institute of Technology

Bayesian Augmentation Of Cnn-Lstm For Video Classification With Uncertainty Measures, Emmie K. Swize

Theses and Dissertations

The success of Department of Defense (DoD) missions rely heavily on intelligence, surveillance, and reconnaissance (ISR) capabilities, which supply information about the activities and resources of an enemy or adversary. To secure this information, satellites and unmanned aircraft systems collect video data to be classified by either humans or machine learning networks. Traditional automated video classification methods lack measures of uncertainty, meaning the network is unable to identify those cases in which it predictions are made with significant uncertainty. This leads to misclassification, as the traditional network classifies each observation with same amount of certainty, no matter what the observation …


Defensive Counterair For Air Base Air Defense Using Directed Energy And Kinetic Energy Weapons, Andrew S. Wilson 2021 Air Force Institute of Technology

Defensive Counterair For Air Base Air Defense Using Directed Energy And Kinetic Energy Weapons, Andrew S. Wilson

Theses and Dissertations

Air bases in key locations provide a strategic advantage to the countries that access them, and are at constant threat from adversaries. This research seeks to determine the optimal maneuvering of a fixed number of fighter aircraft in a combat air patrol for defensive counterair to maximally and effectively attrit the inbound cruise missile threat to a stationary high value asset such as an air base. The problem formulation identifies multiple objectives for the model: minimize the distance traveled for the fighters, minimize the time utilized to engage the incoming cruise missiles, and maximize the number of cruise missiles destroyed. …


Meta-Heuristic Optimization Methods For Quaternion-Valued Neural Networks, Jeremiah P. Bill 2021 Air Force Institute of Technology

Meta-Heuristic Optimization Methods For Quaternion-Valued Neural Networks, Jeremiah P. Bill

Theses and Dissertations

In recent years, real-valued neural networks have demonstrated promising, and often striking, results across a broad range of domains. This has driven a surge of applications utilizing high-dimensional datasets. While many techniques exist to alleviate issues of high-dimensionality, they all induce a cost in terms of network size or computational runtime. This work examines the use of quaternions, a form of hypercomplex numbers, in neural networks. The constructed networks demonstrate the ability of quaternions to encode high-dimensional data in an efficient neural network structure, showing that hypercomplex neural networks reduce the number of total trainable parameters compared to their real-valued …


Reducing Military Personnel Flight Wait Times Using A Simulation, Matthew D. Cornman 2021 Air Force Institute of Technology

Reducing Military Personnel Flight Wait Times Using A Simulation, Matthew D. Cornman

Theses and Dissertations

A shortage of resources and system failures have put a strain on Military Personnel Flights (MPFs) being able to service their customers in a timely manner. Prolonged customer wait times are becoming a common problem in most MPFs creating problems between the relationship of the customers and leadership. This research uses historical data of an MPF to develop a simulation model of daily operations in an MPF. Subject matter expertise of current MPF operations and resource levels were used to provide a baseline model of the MPF queuing system. The analysis examines the effects of number of Defense Enrollment Eligibility …


The Effects Of Customer Segmentation, Borrowers' Behaviours And Analytical Methods On The Performance Of Credit Scoring Models In The Agribusiness Sector, Daniela Lazo, Raffaella Calabrese, Cristian Bravo Roman 2021 Universidad de Talca

The Effects Of Customer Segmentation, Borrowers' Behaviours And Analytical Methods On The Performance Of Credit Scoring Models In The Agribusiness Sector, Daniela Lazo, Raffaella Calabrese, Cristian Bravo Roman

Statistical and Actuarial Sciences Publications

The main aim of this study is to analyse the joint effects of customer segmentation, borrowers' characteristics and modelling techniques on the classification accuracy of a scoring model for agribusinesses. To this end, we used data provided by a Chilean company on 161,163 loans from January 2007 to December 2013. We considered random forest, neural network and logistic regression models as analytical methods. Regarding the borrowers' profiles, we examined the effects of socio-demographic, repayment-behaviour, agribusiness-specific and credit-related variables. We also segmented the customers as individuals, SMEs and large holdings. As the segments show different risk behaviours, we obtained a better …


A Multi-Agent Semi-Cooperative Unmanned Air Traffic Management Model With Separation Assurance, Yanchao Liu 2021 Wayne State University

A Multi-Agent Semi-Cooperative Unmanned Air Traffic Management Model With Separation Assurance, Yanchao Liu

Industrial and Systems Engineering Faculty Research Publications

This paper presents an air traffic management framework to enable multiple fleets of unmanned aerial vehicles to traverse dense, omni-directional air traffic safely and efficiently. The main challenge addressed here is separation assurance in the absence of full coordination and communication. In this framework, each fleet is independently managed by a routing agent, which progressively plans the non-overlapping move-ahead corridors for vehicles in the fleet by solving a nonlinear optimization model. The model is artfully designed so that agents of different fleets need not engage in complicated multilateral communications or make guesses about external vehicles’ flight intents to maintain effective …


Dynamic Analysis Of The Implementation Of The Blockchain Technology In The Supply Chain, Rehab Ali 2021 University of Central Florida

Dynamic Analysis Of The Implementation Of The Blockchain Technology In The Supply Chain, Rehab Ali

Electronic Theses and Dissertations, 2020-2023

Blockchain technology is a new digital technology that has been disrupting the way businesses are performing. It is a decentralized and distributed ledger that enables transactions of any form of value. As blockchain technology provides visibility, transparency, and security through the multi-agent system, the supply chain sector is one of its critical and promising applications. In a highly dynamic environment, the supply chain's efficiency needs to be measured from a blockchain perspective. As the main benefit of blockchain technology is the visibility and real-time access to data, blockchain technology's preeminent affected areas within the supply chain are the responsiveness to …


Factors That Affect The Successful Implementation Of Quality Management Systems In Healthcare, Mustafa Rawshdeh 2021 University of Central Florida

Factors That Affect The Successful Implementation Of Quality Management Systems In Healthcare, Mustafa Rawshdeh

Electronic Theses and Dissertations, 2020-2023

Modern Organizations must be high performing to sustain and grow their operations. This is particularly true for healthcare organizations as they have complex and sensitive operations. One way to improve organizational performance is to adopt Quality Management Systems (QMSs). QMSs organize and improve the effectiveness of all processes to meet stakeholder requirements and achieve organizational performance improvements in alignment with strategic goals. However, the value of QMSs is dependent on successful implementation, which is reportedly quite challenging. This doctoral research examines the factors that affect the successful implementation of QMSs in healthcare. First, a systematic analysis of the published literature …


Total Quality And Innovation Management In Hospital, Suebsakul Tonjang 2021 Faculty of Engineering

Total Quality And Innovation Management In Hospital, Suebsakul Tonjang

Chulalongkorn University Theses and Dissertations (Chula ETD)

Previously, quality of care and customers' satisfaction in healthcare services is fulfilled only through total quality management (TQM) which as a core management philosophy, as adopted by many healthcare organizations. Nevertheless, TQM focuses on incremental improvement may prove insufficient to address the new technology and innovation-driven organization with a faster pace. Therefore, this research aimed to integrate quality and innovation management in healthcare affecting healthcare performance. To propose the key factor of both TQM and innovation management in healthcare, we conducted a systematic literature review. Then, TQM and innovation management factors were combined and integrated with ISO 56002 as to …


An Integrated View Of Knowledge Management Enablers, Components, And Benefits: Comprehensive Literature Review, Shuaibu Hassan Usman, Jigish Zaveri, Aminu Hamza 2021 Morgan State University

An Integrated View Of Knowledge Management Enablers, Components, And Benefits: Comprehensive Literature Review, Shuaibu Hassan Usman, Jigish Zaveri, Aminu Hamza

Journal of International Technology and Information Management

The key to success in the 21st century, knowledge-based economy, will be the effective and efficient management of knowledge. Knowledge Management (KM) has a direct impact on organizational success. KM in a knowledge-based economy entails growth, value, and improving living standards through knowledge creation, storage, and dissemination. This study aims to integrate KM enablers, components, and benefits into a single view through a comprehensive literature search. The integrative view of these three factors would facilitate the understanding of KM initiatives within organizations. This paper performs a comprehensive literature review to explain the KM enablers, components, and benefits. From the …


การเพิ่มอัตราคุณภาพสินค้าดีของกระบวนการผลิตเส้นใยสังเคราะห์ชนิดสั้น, เกวลี วรนันท์ 2021 คณะวิศวกรรมศาสตร์

การเพิ่มอัตราคุณภาพสินค้าดีของกระบวนการผลิตเส้นใยสังเคราะห์ชนิดสั้น, เกวลี วรนันท์

Chulalongkorn University Theses and Dissertations (Chula ETD)

วิทยานิพนธ์ฉบับนี้จัดทำขึ้นเพื่อปรับปรุงอัตราคุณภาพของเส้นใยสังเคราะห์ชนิดสั้น โดยมุ่งเน้นในการลดปริมาณสินค้าที่ไม่ได้คุณภาพ รวมทั้งของเสียที่เกิดขึ้นในกระบวนการผลิต ซึ่งเริ่มเก็บรวบรวมข้อมูลย้อนหลังตั้งแต่เดือนธันวาคม 2562 ถึง ตุลาคม 2563 และแสดงปัญหาที่เกิดขึ้นในกระบวนการผลิตด้วยกราฟพาเรโต แล้วทำการระดมความคิดเพื่อวิเคราะห์หาปัจจัยที่มีผลต่ออัตราคุณภาพด้วยแผนผังเหตุ และผล จากนั้นทำการวิเคราะห์ข้อบกพร่องและผลกระทบปัญหาด้านคุณภาพเพื่อทำการประเมินความรุนแรงของการเกิดข้อบกพร่อง โอกาสในการเกิดข้อบกพร่อง และความสามารถในการตรวจจับข้อบกพร่อง เพื่อคำนวณหาค่าดัชนีความเสี่ยง โดยจะทำการเลือกปัญหาที่มีค่าดัชนีความเสี่ยงมากที่สุดได้แก่ 1) ลมเย็นออกไม่สม่ำเสมอ 2) การเคลื่อนที่ของถังใส่เส้นใยและลูกกลิ้งไม่สัมพันธ์กัน หลังจากทำการปรับปรุงปัญหาที่ส่งผลต่ออัตราคุณภาพ พบว่าอัตราคุณภาพสินค้าดีมีปริมาณเพิ่มขึ้นจากเดิมร้อยละ 92.97 เป็นร้อยละ 95.79 และอัตราคุณภาพสินค้าไม่ได้คุณภาพ และของเสียมีปริมาณลดลงจากเดิมร้อยละ 7.03 เป็นร้อยละ 4.21 ซึ่งคิดเป็นเงินจะมีกำไรเพิ่มขึ้นเฉลี่ยเดือนละ 130,892.63 บาท เมื่อทำการผลิตที่ 93 ตันต่อวัน หลังจากนั้นทางบริษัทกรณีศึกษาจึงทำการเพิ่มกำลังการผลิตเพื่อตอบสนองความต้องการของลูกค้าเป็น 96 ตันต่อวัน


ปัจจัยที่ส่งผลต่อประสิทธิภาพในการผสมแบบข้นหนืด, วรกาญจน์ คณกร 2021 คณะวิศวกรรมศาสตร์

ปัจจัยที่ส่งผลต่อประสิทธิภาพในการผสมแบบข้นหนืด, วรกาญจน์ คณกร

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้มีวัตถุประสงค์เพื่อศึกษาปัจจัยที่ส่งผลต่อประสิทธิภาพในการผสมแบบข้นหนืดด้วยเครื่อง Hi-Shear Vacuum Mixer (HSVM) โดยตรวจสอบจากการวัดค่าความสูงของตะกอนในการชงไซรัปสีน้ำตาลต้องไม่เกินเกณฑ์มาตรฐาน 13 มิลลิเมตร และค่าความสามารถด้านสมรรถนะของกระบวนการผลิตระยะสั้น (Cpk) ของเครื่องจักรต้องไม่ต่ำกว่าเกณฑ์ โดยนำเอาแผนผังก้างปลาควบคู่กับตารางความสัมพันธ์ของสาเหตุและผลทำการวิเคราะห์ถึงสาเหตุของปัญหา จากนัั้นทำการคัดกรองปัจจัยเบื้องต้นด้วยวิธี FMEA พร้อมทั้งประยุกต์ใช้เทคนิคการออกแบบการทดลองเศษส่วนเชิงแฟคทอเรียลแบบสองระดับ (2k Factorial Fraction Design) เพื่อลดปัจจัยหลักที่ไม่มีอิทธิพลออก ทำให้ได้ปัจจัยหลักที่มีอิทธิพลอย่างมีนัยสำคัญจำนวน 3 ปัจจัย ได้แก่ 1.ระดับของชุดตะแกรงหัวปั่นผสม 2.ความเร็วรอบของชุดหัวปั่นผสม และ 3.อุณหภูมิเริ่มต้นของวัตถุดิบของเหลว พร้อมทั้งประยุกต์ใช้การออกแบบการทดลองพื้นผิวตอบสนอง (Response Surface Method) แบบบอกซ์-เบห์นเคน (ฺBox-Behnken) เพื่อหาค่าระดับของปัจจัยที่เหมาะสมของทั้ง 3 ปัจจัย โดยค่าความสูงของตะกอนไม่เกิน 10±1 มิลลิเมตร โดยมีค่าก่อนการปรับปรุงกระบวนการผลิตไซรัปสีน้ำตาล มีค่าเฉลี่ยความสูงของตะกอนเป็น 20.89±2.26 มิลลิเมตร และค่า Cpk ของเครื่องผสม HSVM นั้นมีค่าเป็น -3.93 ซึ่งมีค่าต่ำกว่าเกณฑ์มาตรฐาน จากการวิเคราะห์ผลการทดลองสรุปได้ว่าค่าระดับปัจจัยที่เหมาะสมในการตั้งเครื่องผสม HSVM มีดังนี้ ระดับของชุดตะแกรงหัวปั่นผสม อยู่ที่ระดับแบบต่ำ ความเร็วรอบของชุดหัวปั่นผสมอยู่ที่ 2000 รอบ/นาที และอุณหภูมิเริ่มต้นของวัตถุดิบของเหลวอยู่ที่ 72.5 องศาเซลเซียส ซึ่งได้ทำการยืนยันผลโดยการปรับตั้งค่าเครื่องทำการผลิตจริงพร้อมติดตามผล ผลหลังการปรับปรุงกระบวนการผลิตไซรัปสีน้ำตาล มีค่าเฉลี่ยความสูงของตะกอนเป็น 10.48±0.32 มิลลิเมตร และค่า Cpk ของเครื่องผสม HSVM นั้นมีค่าเป็น 2.56 ซึ่งอยู่ในเกณฑ์ดีเกินคาด และยังส่งผลให้ประสิทธิภาพของเครื่องผสมไซรัป HSVM นั้นผลิตไซรัปได้โดยไม่เกิดของเสียจากกระบวนการอีกเลย


Comparison Of Dashboard Development Between Waterfall Model And Agile Methodologies, Siribhop Yooyongchuen 2021 Faculty of Engineering

Comparison Of Dashboard Development Between Waterfall Model And Agile Methodologies, Siribhop Yooyongchuen

Chulalongkorn University Theses and Dissertations (Chula ETD)

Agile Methodology is a concept that focus on communication between product developers and users. The objective is to make product be rapidly developed and effectively meets users’ needs. Objective of this study is to compare dashboard development method between agile methodology and waterfall model. There are 3 dimensions in comparison; speed of development, users’ satisfaction, and efficiency of dashboard. The study used descriptive and experimental research. The sample is dashboard users in Company L. The study is conducted by establishing timeline of dashboard development, semi-constructed interview, and survey applying Technology Acceptance Model and Theory of Planned Behavior. The result of …


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