Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, School of Engineering, System Design and Management Program, Engineering and Management Program, 2019. / Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2019. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 120-122). / The olfactory system remains one of the least well understood out of the five senses. In this thesis we examined the mappings of the odors to pathways in the brain as an initial assessment for the feasibility of digital odor. The results confirmed previous findings that each odor activated 1-6 neurons. Next, we looked at a controversial theory of odor detection using vibrations popularized recently by Luca Turin and its implications using Human Centered Design (HCD). We analyze the viability of products that could result from synthesizing digital smell using frequencies in the infrared range produced by vibrations and the general public's perceptions of these products. The results show that the technology is not readily accepted by users at the present time. / by Jun Wu. / S.M. in Engineering and Management / S.M. / S.M.inEngineeringandManagement Massachusetts Institute of Technology, School of Engineering, System Design and Management Program, Engineering and Management Program / S.M. Massachusetts Institute of Technology, Department of Mechanical Engineering

Thesis: Nav. E., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2019 / Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, 2019 / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 161-165). / As the nation's security needs call for a growing naval fleet, the public-private industrial base for construction and weapon system acquisition will be stressed to perform at a high level of operational excellence. While reaching the required fleet size is a major challenge, ships are the delivery vehicles for complex weapons systems whose design and production is equally critical to deliver capability that the Fleet needs. Underperformance in defense acquisitions is found to be caused by complexity, uncertainty, and risk manifested through poor requirements that are unadaptable to the changing reality of the global security landscape. This thesis hypothesizes that use of model-based engineering (MBE) will enable the needed efficiency and responsiveness. / MBE consists of digital tools motivated by the principles of traceability and high-velocity design iteration that collectively connect requirements to technical specifications in a model-centric format in contrast to the document-based form prevalent today. Given the problem of disengagement between the request for proposal and the finished product, prior case examples of using MBE elsewhere in the defense and industrial establishment show a bridge for the divide between capability requirements and technical realization. An original process-based shipbuilding production model further demonstrates how understanding effects of component changes affects overall system production. Changes in a ship's required operational capabilities, translated to technical design parameters, are mapped to production steps. The simulated performance is compared across three successive stages of construction when the change is ordered. / Results of model simulations demonstrate that similar MBE applications contribute to increased early requirement fidelity, decreases in rework through missed changes, and more rapid design iteration when the models used are properly verified and validated. Verification and validation (V&V) must be performed in a very specific environment to engender confidence in model usage through a systemic framework. One method of V&V, System Theoretic Process Analysis for Security, is illustrated using an original concept illustration of a Fictional Submarine Strategic Missile. The domain of MBE is expanded to include definition of cybersecurity requirements for a new weapon system to illustrate an iteration of model-based system design. The modeling of these requirements contributes to validated resilience upon delivery, decreasing the likelihood that cyber-physical systems will be forced to rely on time-consuming updates that delay the capability delivery. / by Travis J. Rapp. / Nav. E. / S.M. in Engineering and Management / Nav.E. Massachusetts Institute of Technology, Department of Mechanical Engineering / S.M.inEngineeringandManagement Massachusetts Institute of Technology, System Design and Management Program

Thesis: Nav. E., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2019 / Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, 2019 / Cataloged from PDF version of thesis. / Includes bibliographical references (page 83). / This thesis describes the development and execution of a test program to determine the suitability of an asymmetric propeller for unmanned underwater vehicles (UUV). The idea to utilize a single blade propeller had been pioneered in the past for aviation as an attempt to generate greater thrust, but was quickly abandoned. Recently, Woods Hole Oceanographic Institute reevaluated the concept for use on a UUV, but for two different objectives. The first was a possible improvement in propulsive efficiency. For UUVs meant to operate for long periods without recharging, any increase in propeller efficiency can result in more time on station. The second object was to allow for an alternate method of steering the UUV. By controlling the speed of the propeller through each revolution, the thrust at any given point can be controlled. This allows for a non-uniformly distributed thrust about the longitudinal axis of the UUV which can be used to steer the UUV. This thesis evaluated the efficiency of using such a propeller. This data was used to determine the suitability for UUVs and in which use cases an asymmetric propeller used for propulsion and steering. Due to issues during testing the control authority provided along a variety of speeds could not be determined for comparison to a traditional propeller and rudder configuration. / by Robert Beltri Carelli. / Nav. E. / S.M. in Engineering and Management / Nav.E. Massachusetts Institute of Technology, Department of Mechanical Engineering / S.M.inEngineeringandManagement Massachusetts Institute of Technology, System Design and Management Program

Thesis: Nav. E., Massachusetts Institute of Technology, Department of Mechanical Engineering, May, 2020 / Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, May, 2020 / Cataloged from the official PDF of thesis. / Includes bibliographical references (pages 107-112). / Analysis of U.S. Navy Ice Exercise 2016 (ICEX16) data, through a collaboration with MIT Lincoln Laboratory, demonstrated that towed array curvature commonly exhibited heading differences up to 100° and never maintained heading differences less than 30° between the forward compass and the aft compass. These deviations reflected a disparity from the underlying assumption that the towed array remained rigid with no deviations from a rigid, straight-line configuration. Using lessons learned from ICEX16, a field experiment in Massachusetts Bay 2019 (FEX19) tested whether a hexagonal search pattern would sufficiently address the curvature concern, thereby, validate the underlying rigid, straight-line beamformer assumption more commonly used. Results from the experiment showed that a hexagonal search pattern maintained a heading differences of less than 4° within 79 seconds of an initiation of a 60° maneuver. / This was a marked improvement when compared to ICEX16's vehicle maneuvers, which never maintained a heading difference of less than 30°. Even with this improvement in FEX19, 39.6% of the acoustic data was collected when the towed array did not meet the straight-line assumption. Use of the hexagonal search pattern, in two instances during U.S. Navy Ice Exercise 2020 (ICEX20), showed that 45.1% and 27.1% of the collected acoustic data did not meet the towed-array straight-line assumption. Although this realization will influence operators to minimize maneuvers that introduce significant deviations from the underlying beamforming model, field experiments often call for sharper maneuvers. This realization spurred the development of a beamformer that modeled towed array curvature using headings, effectively tangential slopes, at either end of the hydrophone portion of the towed array with a known fixed length to predict how the towed array bends. / Analysis of FEX19 showed that the hyperbola-shaped beamformer output aligned to GPS heading data over 30% of the experimental window compared to less than 10% for the straight-line beamformer. This improvement held true even when the towed array had little or no curvature. / by Michael Kaiping Liu. / Nav. E. / S.M. in Engineering and Management / Nav.E. Massachusetts Institute of Technology, Department of Mechanical Engineering / S.M.inEngineeringandManagement Massachusetts Institute of Technology, System Design and Management Program

Thesis: Nav. E., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2019 / Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, 2019 / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 85-86). / Increased operational demands on Navy vessels extend time at sea and service life, making the accurate prediction of catastrophic failures increasingly challenging. The high value of these capital assets puts great pressure on designers and decision-makers as they work towards preventing such failures while balancing both engineering and material cost. The current method for the quantification of extreme events is direct Monte Carlo simulation supplemented by complex statistical models. When such models are not sufficiently bound by physics-based simulation, the noise of statistical uncertainty quickly overpowers the response predictions for rare events. This thesis builds on previous work at the MIT Stochastic Analysis and Non-linear Dynamics (SAND) lab for the quantification of extreme events using wave groups. By separating the event probability from the physics models, we are able to capture rare events in ship motion and loading conditions for a modest computational cost. Improvements to the wave groups methodology ensured the slope and amplitude of the incident waves reflected the waves encountered in a given wave spectrum. The remaining discussion explores the value of a near-real-time risk analysis tools in reference to ship design and ship operations, with unique application to Navy and commercial vessels. / by Uditbhan S. Rathore. / Nav. E. / S.M. in Engineering and Management / Nav.E. Massachusetts Institute of Technology, Department of Mechanical Engineering / S.M.inEngineeringandManagement Massachusetts Institute of Technology, System Design and Management Program

Thesis: Nav. E., Massachusetts Institute of Technology, Department of Mechanical Engineering, May, 2020 / Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, May, 2020 / Cataloged from the official PDF of thesis. / Includes bibliographical references (pages 625-626). / Trends in power system simulation that demand computationally-intensive, physics-based models may impede the acquisition of useful results for applications like condition-based maintenance [1], electrical plant load analysis (EPLA) [2], and the scheduling and tasking of finite generation and distribution resources. A tool that can quickly evaluate many scenarios, as opposed to intense, high fidelity modeling of a single operating scenario, may best serve these applications. This thesis presents a behavioral simulator that can quickly emulate the operation of a relatively large collection of electrical loads, providing "what-if" evaluations for more complete exploration of a design or plant operating envelope. Comparisons to field data collected from a microgrid on-board a 270 foot US Coast Guard "Famous" Class medium endurance cutter demonstrate the utility of this tool and approach. The usefulness of this tool is further demonstrated by showing simulated EPLA load factors within 10%of observed load factors over comparable mission sets, both inport and underway. Finally, this thesis will discuss the lessons learned during SPS development and testing, specifically, the need to expand its modeling capability so it can support direct current (DC) electrical distribution systems. The SPS, in its current form can only model alternating (AC) electrical distribution systems. / by Thomas Deeter. / Nav. E. / S.M. in Engineering and Management / Nav.E. Massachusetts Institute of Technology, Department of Mechanical Engineering / S.M.inEngineeringandManagement Massachusetts Institute of Technology, System Design and Management Program

Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, 2019 / Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2019 / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 110-117). / The World Resources Institute (WRI) and United Nations Food and Agriculture Organization (FAO) estimate that global agricultural food production will need to increase 56% between 2010 and 2050 to meet projected caloric demands of the growing population. Given the finite amount of global land area as well as the impacts agricultural land-use and production have on greenhouse gas emissions (GHGs), achieving this increase in consonance with climate change reduction goals presents a formidable challenge. In the past, large yield improvements have been realized from genetically modified seeds, synthetic fertilizers and pesticides, increased mechanization, and improved irrigation, but these innovations have also brought negative side effects. For example, the increasing weight of mechanized farm equipment has led to significant man-made soil compaction. / Soil compaction is the increase in bulk density, or reduction of air pore space, in a soil matrix, and it can lead to restricted root growth, poor water and nutrient infiltration, and reductions in yield. Specifically, man-made compaction has been estimated to lead to 15-20% reductions in crop yield, leading to $40-45 Billion in annual financial losses in the United States alone. Mechanical tillage is one of the most common remedies for loosening compacted soil, but the process damages soil structure and overall soil health, making it a solution that should optimally be used sparingly, only in areas where soil is severely compacted. A key challenge to enabling this, however, is compaction sensing and mapping at the field scale. In response to this challenge, a research project was undertaken through MIT Beaver Works, a collaboration with MIT Lincoln Laboratory, to explore systems-based solutions for real-time soil compaction sensing and mapping. / Through that work, a high-level system design for measuring soil compaction at the field scale was proposed based on electromagnetic sensing, including the use of ground penetrating radar (GPR) and electromagnetic induction (EMI) sensors. This thesis aims to address the highest risk aspects of the proposed approach through modelling, laboratory testing, and field testing, progressing theoretical results into increasingly more realistic settings to better understand practical limitations and potential challenges with the technical approach. / by Matthew Rosen. / S.M. in Engineering and Management / S.M. / S.M.inEngineeringandManagement Massachusetts Institute of Technology, System Design and Management Program / S.M. Massachusetts Institute of Technology, Department of Mechanical Engineering

Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, 2019 / Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2019 / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 102-113). / Global food production faces severe challenges that will test the world's ability to mobilize technology, industry participants, and governments to develop a sustainable response. Feeding a growing population and accommodating for rapidly evolving diets calls for a significant expansion in production. Progress is needed to help produce more with less, limit the environmental impact of chemical inputs, and curb agricultural greenhouse gas emissions. The agricultural workforce is facing increasingly challenging economic conditions, a lackluster generation of new producers, and industrywide labor shortages that threaten the continuity of food production. Innovative systems are crucially needed to boost productivity, while protecting natural resources and sustaining a vital workforce. In the past decade, Agriculture has witnessed the rise of a novel proponent of such systems stemming from an unprecedented wave of investments, innovations, and entrepreneurial ventures, referred to as AgTech for the purpose of this work. The aim of this work is initially to analyze the most pressing challenges faced by global food production, communicate on their magnitude, and highlight opportunities for innovation. In parallel, this work aims to increase awareness on the magnitude of food waste and loss, and present opportunities associated with food waste reduction and prevention. Then, this work will briefly define AgTech, present its benefits, and evaluate its impact on the food production industry. Based on this evaluation, limitations of AgTech will be presented, and industrywide recommendations to enhance its impact will be proposed. Finally, this work will propose a concept to reduce food waste in agricultural production. / by Guillaume Defrance de Tersant. / S.M. in Engineering and Management / S.M. / S.M.inEngineeringandManagement Massachusetts Institute of Technology, System Design and Management Program / S.M. Massachusetts Institute of Technology, Department of Mechanical Engineering

Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, School of Engineering, System Design and Management Program, Engineering and Management Program, 2015. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 101-103). / This thesis explores drivers of mission performance outcomes through dynamics associated with intelligence and operational processes. System dynamics methodology can provide a foundation for exploration of these processes within the intelligence cycle. In the Army's current structure, intelligence capacity falls short of what combat battalions need in the modern operational environment. Is this shortfall a remnant of an archaic design, or has the intelligence process itself changed so significantly that the drivers of intelligence capacity require revision? There has been a significant structural transformation of Army units over the past two decades. This has also impacted the intelligence community both within and outside of the Army. Advances in information technology have resulted in a prodigious increase in collection platforms, digital data streams, and digital architecture at the tactical level. These transformations have significantly changed the nature of tactical intelligence analysis and therefore necessitate an appreciative update to analyst capabilities. A scrutiny of the analyst's role in unit operations reveals four major components of competency that are imperative to analysts' abilities. Design structure matrices reveal the relationship of these components across 132 competency specifications from Army doctrine, and expose performance challenges from lack of proficiency within information processing methodologies. A system dynamics model exposes the cost of analyst performance shortfalls. It is proven that increased reliance on shortcut methods erodes analysts' ability to improve skillsets, which in turn is detrimental to the Army's intelligence community and may impair overall future US military combat capability. Considered paths to improvement are discussed. / by Jillian Marie Wisniewski. / S.M. in Engineering and Management

Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, School of Engineering, System Design and Management Program, Engineering and Management Program, 2016. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 45-47). / The complexities around building, testing, and flying aircraft span many different domains. Some of these domains include processes, people, and tools, of which affect the way work is performed on aircraft. In this thesis, communication tools and the organizations involved in troubleshooting and readying aircraft for flight at an aircraft manufacturer's flight line was analyzed using Design Structure Matrix (DSM) methods. Mapping the two DSMs together into a larger multi-domain matrix (MDM) provided insight to the ways information is transferred, and clarified ways to streamline available information to the various stakeholders, while reducing effort and increasing information quality. One recommendation to streamline flows was to design a system that leverages existing responsibilities of Manufacturing, Quality and Engineering and applying them in an electronic format by utilizing computers (a tool found at every level of employee) to capture live data in an organic fashion. The proposed solution would provide valuable information to other stakeholders at a reduced effort, translating to savings. Savings in the form of interaction reductions could range from 235 to 117, at a 50% reduction in interactions across all organizations. It would also provide a method by which to share information at faster speeds, ensuring all stakeholders are engaged with the latest information. Information quality and speed would further help reduce the risk of flight delays, and improve the customer experience. Overall, reductions in efforts from all organizations and an improved customer experience through rapid and accurate information dissemination, will ultimately reduce cost and promote business and growth. / by Eli Grun. / S.M. in Engineering and Management