Hydrogen Fuel in Support of Unmanned Operations in an EABO Environment

NPS NRP Project PosterNavy and Marine Corps planners developed the Expeditionary Advanced Base Operations (EABO) concept of operations to provide maritime commanders with more options for future sea control operations. Additionally, Littoral Operations in a Contested Environment (LOCE) is the concept for logistical support to multiple EABO sites. Finally, NAVPLAN 2020 and the Tri-Service Maritime Strategy detail the importance of unmanned systems capabilities to future warfighting. Many unmanned undersea and aerial systems currently in development are looking to alternative energy sources, including hydrogen, to maximize operational reach and persistence. The picture is clear, the future combat environment demands risk-worthy platforms to perform sea denial as a low-signature "inside force' that is untethered from a large petroleum supply chain. This study will assess hydrogen requirements for use as a fuel in an EABO environment to inform development of a capability evolution plan. This work will apply a holistic, systems engineering approach to develop a finite set of scenarios for hydrogen use as a fuel in an EABO environment. One scenario will be modelled to determine short, mid, and long-term requirements for: hydrogen generation and storage, fuel-cell numbers and capabilities, facilities, and safety or other '-ilities' of relevance. The goal is to investigate benefits and system of systems trade-offs with the objective of delaying fuel resupply to the greatest extent possible. This will inform identification of DOTMLPF gaps to hydrogen adoption as an enabler of EABO in LOCE and support development of a capability evolution plan. This work directly supports technology assessment & transition in support of ONR S&T objectives, as well as the analysis & assessment needs of OPNAV N-94, MCWL, and NECC. An interdisciplinary team of students and faculty from Systems Engineering, Mechanical Engineering, and Operations Research will contribute. Systems Engineering will lead the study.N9 - Warfare SystemsThis 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.

Molecular characterization and expression of DERL1 in bovine ovarian follicles and corpora lutea

The endoplasmic reticulum (ER) is a major site of protein synthesis and facilitates the folding and assembly of newly synthesized proteins. Misfolded proteins are retrotranslocated across the ER membrane and destroyed at the proteasome. DERL1 is an important protein involved in the retrotranslocation and degradation of a subset of misfolded proteins from the ER. We characterized a 2617 bp cDNA from bovine granulosa cells that corresponded to bovine DERL1. Two transcripts of 3 and 2.6 kb were detected by Northern blot analysis, and showed variations in expression among tissues. During follicular development, DERL1 expression was greater in day 5 dominant follicles compared to small follicles, ovulatory follicles, or corpus luteum (CL). Within the CL, DERL1 mRNA expression was intermediate in midcycle, and lowest in late cycle as compared to early in the estrous cycle. Western blot analyses demonstrated the presence of DERL1 in the bovine CL at days 5, 11, and 18 of the estrous cycle. Co-immunoprecipitation using luteal tissues showed that DERL1 interacts with class I MHC but not with VIMP or p97 ATPase. The interaction between DERL1 and MHC I suggests that, in the CL, DERL1 may regulate the integrity of MHC I molecules that are transported to the ER membrane. Furthermore, the greater expression of DERL1 mRNA is associated with the active follicular development and early luteal stages, suggesting a role of DERL1 in tissue remodeling events and maintenance of function in reproductive tissues

Hydrogen Fuel in Support of Unmanned Operations in an EABO Environment

NPS NRP Technical ReportNavy and Marine Corps planners developed the Expeditionary Advanced Base Operations (EABO) concept of operations to provide maritime commanders with more options for future sea control operations. Additionally, Littoral Operations in a Contested Environment (LOCE) is the concept for logistical support to multiple EABO sites. Finally, NAVPLAN 2020 and the Tri-Service Maritime Strategy detail the importance of unmanned systems capabilities to future warfighting. Many unmanned undersea and aerial systems currently in development are looking to alternative energy sources, including hydrogen, to maximize operational reach and persistence. The picture is clear, the future combat environment demands risk-worthy platforms to perform sea denial as a low-signature "inside force' that is untethered from a large petroleum supply chain. This study will assess hydrogen requirements for use as a fuel in an EABO environment to inform development of a capability evolution plan. This work will apply a holistic, systems engineering approach to develop a finite set of scenarios for hydrogen use as a fuel in an EABO environment. One scenario will be modelled to determine short, mid, and long-term requirements for: hydrogen generation and storage, fuel-cell numbers and capabilities, facilities, and safety or other '-ilities' of relevance. The goal is to investigate benefits and system of systems trade-offs with the objective of delaying fuel resupply to the greatest extent possible. This will inform identification of DOTMLPF gaps to hydrogen adoption as an enabler of EABO in LOCE and support development of a capability evolution plan. This work directly supports technology assessment & transition in support of ONR S&T objectives, as well as the analysis & assessment needs of OPNAV N-94, MCWL, and NECC. An interdisciplinary team of students and faculty from Systems Engineering, Mechanical Engineering, and Operations Research will contribute. Systems Engineering will lead the study.N9 - Warfare SystemsThis 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.

Hydrogen Fuel in Support of Unmanned Operations in an EABO Environment

NPS NRP Executive SummaryNavy and Marine Corps planners developed the Expeditionary Advanced Base Operations (EABO) concept of operations to provide maritime commanders with more options for future sea control operations. Additionally, Littoral Operations in a Contested Environment (LOCE) is the concept for logistical support to multiple EABO sites. Finally, NAVPLAN 2020 and the Tri-Service Maritime Strategy detail the importance of unmanned systems capabilities to future warfighting. Many unmanned undersea and aerial systems currently in development are looking to alternative energy sources, including hydrogen, to maximize operational reach and persistence. The picture is clear, the future combat environment demands risk-worthy platforms to perform sea denial as a low-signature "inside force' that is untethered from a large petroleum supply chain. This study will assess hydrogen requirements for use as a fuel in an EABO environment to inform development of a capability evolution plan. This work will apply a holistic, systems engineering approach to develop a finite set of scenarios for hydrogen use as a fuel in an EABO environment. One scenario will be modelled to determine short, mid, and long-term requirements for: hydrogen generation and storage, fuel-cell numbers and capabilities, facilities, and safety or other '-ilities' of relevance. The goal is to investigate benefits and system of systems trade-offs with the objective of delaying fuel resupply to the greatest extent possible. This will inform identification of DOTMLPF gaps to hydrogen adoption as an enabler of EABO in LOCE and support development of a capability evolution plan. This work directly supports technology assessment & transition in support of ONR S&T objectives, as well as the analysis & assessment needs of OPNAV N-94, MCWL, and NECC. An interdisciplinary team of students and faculty from Systems Engineering, Mechanical Engineering, and Operations Research will contribute. Systems Engineering will lead the study.N9 - Warfare SystemsThis 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.

The spin-Peierls instability in spin 1/2 XY chain in the non adiabatic limit

The spin-Peierls instability in spin 1/2 XY chain coupled to dispersionless phonons of frequency $\omega$ has been studied in the nonadiabatic limit. We have chosen the Lang-Firsov variational wave function for the phonon subsystem to obtain an effective spin Hamiltonian. The effective spin Hamiltonian is then solved in the framework of mean-field approximation. We observed a dimerized phase when g is less than a critical value and an anti-ferromagnetic phase when it is greater than a critical value . The variation of lattice distortion, dimerized order parameter and energy gap with spin phonon coupling parameter has also been investigated here.Comment: 15 pages (Revtex, including 5 .ps figures); Submitted to PR

Possible Pairing Symmetry of Three-dimensional Superconductor UPt3_3 -- Analysis Based on a Microscopic Calculation --

Stimulated by the anomalous superconducting properties of UPt$_3$, we investigate the pairing symmetry and the transition temperature in the two-dimensional(2D) and three-dimensional(3D) hexagonal Hubbard model. We solve the Eliashberg equation using the third order perturbation theory with respect to the on-site repulsion $U$. As results of the 2D calculation, we obtain distinct two types of stable spin-triplet pairing states. One is the $f$-wave(B$_1$) pairing around $n = 1.2$ and in a small $U$ region, which is caused by the ferromagnetic fluctuation. Then, the other is the $p_x$(or $p_y$)-wave(E$_1$) pairing in large $U$ region far from the half-filling ($n = 1$) which is caused by the vertex corrections only. However, we find that the former $f$-wave pairing is destroyed by introduced 3D dispersion. This is because the 3D dispersion breaks the favorable structures for the $f$-wave pairing such as the van Hove singularities and the small pocket structures. Thus, we conclude that the ferromagnetic fluctuation mediated spin-triplet state can not explain the superconductivity of UPt$_3$. We also study the case of the pairing symmetry with a polar gap. This $p_z$-wave(A$_1$) is stabilized by the large hopping integral along c-axis $t_z$. It is nearly degenerate with the suppressed $p_x$(or $p_y$)-wave(E$_1$) in the best fitting parameter region to UPt$_3$ ($1.3 \le t_z \le 1.5$). These two p-wave pairing states exist in the region far from the half-filling, in which the vertex correction terms play crucial roles like the case in Sr$_2$RuO$_4$.Comment: 15 pages, 12 figure

Antiferromagnetism and Superconductivity in UPt_3

The short ranged antiferromagnetism recently seen in UPt_3 is proved incompatible with two dimensional (2D) order parameter models that take the antiferromagnetism as a symmetry breaking field. To adjust to the local moment direction, the order parameter twists over very long length scales as per the Imry-Ma argument. A variational solution to the Ginzburg-Landau equations is used to study the nature of the short ranged order. Although there are still two transitions, the lower one is of first order -- in contradiction to experiments. It is shown that the latent heat predicted by the 2D models at the lower transition is too large not to have been seen. A simple periodic model is numerically studied to show that the lower transition can not be a crossover either.Comment: To appear in Journal of Physics: Condensed Matter. 9 pages, 2 figure

A single chain analysis of doped quasi one dimensional spin 1 compounds: paramagnetic versus spin 1/2 doping

We present a numerical study of single chain models of doped spin 1 compounds. We use low energy effective one-dimensional models for both the cases of paramagnetic and spin-1/2 doping. In the case of paramagnetic doping, the effective model is equivalent to the bond disordered spin-1/2 chain model recently analyzed by means of real space renormalization group by Hyman and Yang. By means of exact diagonalizations in the XX limit, we confirm the stability of the Haldane phase for weak disorder. Above a critical amount of disorder, the effective model flows to the so called random singlet fixed point. In the case of spin-1/2 doping, we argue that the Haldane phase should be destabilized even for weak disorder. This picture is not in contradiction with existing experimental data. We also discuss the possible occurrence of (unobserved) antiferromagnetically ordered phases.Comment: 13 pages, 7 included figure