"EXTRA!" Using the Newsvendor Model to Optimize War Reserve Storage

17 USC 105 interim-entered record; under review.The article of record as published may be found at https://doi.org/10.22594/dau.21-865.28.04The United States Marine Corps (USMC) Installation and Logistics Command requested a study for determining appropriate inventory levels of war reserve materiel to meet future operational needs under surge demands in uncertain environments. This study sought to explore a potential approach by using the common newsvendor model, but modified for a military scenario. The authors' novel version of this core concept considers the purchase and storage costs of an item and proposes an intangible cost function to capture the consequences of a shortage. Further, they show a sample application of the model using a ubiquitous military item-the BA-5590/U battery. The output of the model provides USMC with a new tool to optimize inventory levels of a given item of interest, depending on scenario inputs.USMC Installation and Logistics Command, Logistics Plans and Operations (Maritime and Geo-Prepositioning Programs) (LPO-2

Proof-of-concept: Achieving Free Propulsion for Flexible UUVs Using Vortical Wakes

A Quad, describing CRUSER Seed Research Program funded research.CRUSER Funded ResearchFY22 Funded Research ProposalConsortium for Robotics and Unmanned Systems Education and Research (CRUSER

Analysis of the specifications and capabilities for the next-generation LRUSV

NPS NRP Project PosterBased on recent priorities for digital engineering strategy within DoD, there is an opportunity for coordinated research efforts tailored towards unmanned surface vehicles. Such efforts are focused on utilization of models to inform decision making based on a single source of authoritative truth, facilitating integration of new technologies and improvement to coordination and communication across stakeholders and engineers. In support of those objectives, this work proposes a coordination of research and design work as appropriate. The primary focus is the analysis of capabilities and functions for the Long Range Unmanned Surface Vessel (LRUSV). To expand that design and to demonstrate the utility of digital engineering as an integrating mechanism, this work will utilize the ship design experience and expertise of Navy engineers and the operational experience of NPS students to conduct innovative early stage design projects that examine both the operational and design considerations for unmanned surface vessels. The operational modeling conducted at NPS will focus on the full spectrum of vessel operations. In accordance with the digital engineering concept, that operational modeling will be conducted simultaneously with an expanded analysis effort, with an emphasis on a shared starting point and problem set. This will result in a more focused tradeoff environment, where operational experience and input informs the design effort of engineers and the design experience of engineers informs operational modeling and capability assessment. Joint Cross-service Research Project ID NPS-21-J218-A (combines topics NPS-21-N218 and NPS-21-M181)PEO C4I (PMW 760)ASN(RDA) - Research, Development, and AcquisitionMarine Corps Forces Command (COMMARFORCOM)This research is supported by funding from the Naval Postgraduate School, Naval Research Program (PE 0605853N/2098). https://nps.edu/nrpChief of Naval Operations (CNO)Approved for public release. Distribution is unlimited.

Analysis of the specifications and capabilities for the next-generation LRUSV

NPS NRP Executive SummaryBased on recent priorities for digital engineering strategy within DoD, there is an opportunity for coordinated research efforts tailored towards unmanned surface vehicles. Such efforts are focused on utilization of models to inform decision making based on a single source of authoritative truth, facilitating integration of new technologies and improvement to coordination and communication across stakeholders and engineers. In support of those objectives, this work proposes a coordination of research and design work as appropriate. The primary focus is the analysis of capabilities and functions for the Long Range Unmanned Surface Vessel (LRUSV). To expand that design and to demonstrate the utility of digital engineering as an integrating mechanism, this work will utilize the ship design experience and expertise of Navy engineers and the operational experience of NPS students to conduct innovative early stage design projects that examine both the operational and design considerations for unmanned surface vessels. The operational modeling conducted at NPS will focus on the full spectrum of vessel operations. In accordance with the digital engineering concept, that operational modeling will be conducted simultaneously with an expanded analysis effort, with an emphasis on a shared starting point and problem set. This will result in a more focused tradeoff environment, where operational experience and input informs the design effort of engineers and the design experience of engineers informs operational modeling and capability assessment. Joint Cross-service Research Project ID NPS-21-J218-A (combines topics NPS-21-N218 and NPS-21-M181)PEO C4I (PMW 760)ASN(RDA) - Research, Development, and AcquisitionMarine Corps Forces Command (COMMARFORCOM)This research is supported by funding from the Naval Postgraduate School, Naval Research Program (PE 0605853N/2098). https://nps.edu/nrpChief of Naval Operations (CNO)Approved for public release. Distribution is unlimited.

Performance Impacts on Unmanned Vehicle and Sensor Capabilities for Standoff Mine Detection in the Very Shallow Water, Surf Zone, and Beach Zone

NPS NRP Project PosterThe Very Shallow Water, Surf Zone, and Beach Zone (VSW/SZ/BZ) environments present extreme challenges for the safe standoff detection of objects, such as mines, explosive ordnance, or natural obstacles such as rocks and shoals. Wave action adversely impacts the performance of conventional unmanned underwater vehicles (UUVs) and remotely operated vehicles (ROVs) that employ sonar or optical imaging sensors. Unmanned aerial vehicles (UAVs) or bottom crawling vehicles that use different sensing modalities may be more effective in these environments. Research is needed to quantify the limitations of current standoff detection sensors deployed from mine countermeasures (MCM) vehicles and recommend promising alternatives for future technology development. This study has two main research objectives. First, we will work with project sponsors and subject matter experts to identify and compare the current state of various technologies for standoff detection of explosive ordnance in the VSW/SZ/BZ. Second, we will leverage NPS experimental capabilities to assess the performance impacts on different MCM vehicles and sensors subjected to wave disturbances in VSW/SZ environments. Specifically, we will conduct semi-captive tests of different MCM vehicle types in a tow tank with wave making capability to simulate VSW/SZ conditions. The measured wave-induced motion profiles will be used to analyze the effects of platform motion on the detection performance of conventional imaging sensors using standard object detection algorithms. Understanding the capabilities of existing technologies, and how they can be expected to perform in these challenging domains, will help inform programs of record and guide future technology investment by the US Navy and US Marine Corps. Research Project ID NPS-21-J212 combines two Topic/Research Projects: NPS-21-M212 and elements of NPS-21-N271.Marine Corps Forces Command (COMMARFORCOM)Navy Expeditionary Combat CommandThis research is supported by funding from the Naval Postgraduate School, Naval Research Program (PE 0605853N/2098). https://nps.edu/nrpChief of Naval Operations (CNO)Approved for public release. Distribution is unlimited.

Performance Impacts on Unmanned Vehicle and Sensor Capabilities for Standoff Mine Detection in the Very Shallow Water, Surf Zone, and Beach Zone

NPS NRP Executive SummaryThe Very Shallow Water, Surf Zone, and Beach Zone (VSW/SZ/BZ) environments present extreme challenges for the safe standoff detection of objects, such as mines, explosive ordnance, or natural obstacles such as rocks and shoals. Wave action adversely impacts the performance of conventional unmanned underwater vehicles (UUVs) and remotely operated vehicles (ROVs) that employ sonar or optical imaging sensors. Unmanned aerial vehicles (UAVs) or bottom crawling vehicles that use different sensing modalities may be more effective in these environments. Research is needed to quantify the limitations of current standoff detection sensors deployed from mine countermeasures (MCM) vehicles and recommend promising alternatives for future technology development. This study has two main research objectives. First, we will work with project sponsors and subject matter experts to identify and compare the current state of various technologies for standoff detection of explosive ordnance in the VSW/SZ/BZ. Second, we will leverage NPS experimental capabilities to assess the performance impacts on different MCM vehicles and sensors subjected to wave disturbances in VSW/SZ environments. Specifically, we will conduct semi-captive tests of different MCM vehicle types in a tow tank with wave making capability to simulate VSW/SZ conditions. The measured wave-induced motion profiles will be used to analyze the effects of platform motion on the detection performance of conventional imaging sensors using standard object detection algorithms. Understanding the capabilities of existing technologies, and how they can be expected to perform in these challenging domains, will help inform programs of record and guide future technology investment by the US Navy and US Marine Corps. Research Project ID NPS-21-J212 combines two Topic/Research Projects: NPS-21-M212 and elements of NPS-21-N271.Marine Corps Forces Command (COMMARFORCOM)Navy Expeditionary Combat CommandThis research is supported by funding from the Naval Postgraduate School, Naval Research Program (PE 0605853N/2098). https://nps.edu/nrpChief of Naval Operations (CNO)Approved for public release. Distribution is unlimited.

Multidisciplinary experiment using steep regular waves to determine ship operating conditions that avoid capsize

The article of record as published may be found at http://dx.doi.org/10.1007/s41939-018-0012-1This paper explores using steep regular waves to identifying safe operating conditions that avoid capsize. The data is from a multidisciplinary experiment using an autonomous scale-model running a proportional-derivative controller in aft of beam steepregularwaves.Thetestexploredrelativewaveheadingsfrom15◦to75◦andspeedsfrom0.1to0.4Froudenumber.This effort analyzes the resultant ship trajectories to determine if the model obtained the desired operating conditions during each run. For slow speeds, safe operating conditions could not be identified since the requested headings could not be achieved. For moderate speeds, most requested headings could be achieved. At the highest speeds, only relative wave headings closer to beam seas could be explored as the model capsized in stern quartering waves. Results show that wavelength and wave steepness have minimal effects on the model’s ability to achieve a desired heading. Finally, only a limited number of runs are required to verify a safe operating condition since capsizes appear to be consistently repeatable. This research highlights the usefulness of using steep regular waves for capsize testing but also some of its limitations

The application of controlled variable magnetic eddy current damping to the study of vortex-induced vibrations

A powerful variable magnetic eddy current damping system has been constructed and utilized in an experimental study of vortex-induced vibrations (VIV). This damping system allows us to impose precise values of nearly ideal viscous damping over a wide range of damping values of interest. This new damping system offers improvements over previously utilized damping methods. Unlike most studies of VIV, where the damping cannot be independently controlled, we are able to impose our system damping independent of the other system parameters. Also, because the system only requires that a thin conductive plate be attached to the oscillating system, the overall mass of the system does not increase dramatically and still allows the investigation of very low mass systems. Finally, the system can operate in a steady-state fashion, supplying a constant damping value for an extended period of time, or in a transient fashion, where the damping value is intentionally varied over time. With this damping system, we have systematically explored both steady and transient damping effects on VIV behavior and provide a brief overview of some sample results

Effects of Damping and Reynolds Number on Vortex-Induced Vibrations

Vortex-induced vibrations have been studied experimentally with emphasis on damping and Reynolds number effects. Our system was an elastically-mounted rigid circular cylinder, free to oscillate only transverse to the flow direction, with very low inherent damping. We were able to prescribe the mass, damping, and elasticity of the system over a wide range of values, with the damping controlled by a custom-made variable magnetic eddy-current damping system. Special emphasis is put on a nontraditional parameter formulation. The advantages of this formulation are explained, and an important new parameter, effective stiffness, is introduced. Using this new formulation, the amplitude and frequency responses are only a function of damping, Reynolds number, and effective stiffness. We show the effects that damping and Reynolds number each have on the amplitude and frequency response profiles and make the interesting observation that changes in damping or Reynolds number have similar effects. The maximum amplitudes of our systems are studied in detail. We theoretically show that they should be functions of both damping and Reynolds number. This allows us to create constant-Reynolds-number curves of maximum amplitude over a large range of damping values, which we call a "generalized" Griffin plot. We also define maximum amplitudes in the case of zero damping as limiting amplitudes, and show that they are only a function of Reynolds number. We experimentally determine our limiting amplitude dependence on Reynolds number over the range 200 &#60; Reynolds number &#60; 5050. Discontinuities in the amplitude response profile are also investigated. The discontinuity between the initial branch and the large-amplitude, upper branch is studied in two ways. First, the time-averaged behavior is examined to understand what controls the discontinuity and look for damping and Reynolds number effects. Second, we track the cycle-by-cycle transient response through this discontinuous amplitude change, induced either by changes in the tunnel velocity or system damping. Finally, we also find a new discontinuity hysteresis region between the lower branch and the desynchronized region, which appears to be a low Reynolds number effect and is only seen in systems with Reynolds number &#60; 1000.</p