A systems engineering analysis of unmanned maritime systems for U.S. Coast Guard missions

The U.S. Coast Guard is uniquely suited to utilize multi-mission unmanned maritime systems (UMS) to maintain its leading role in maritime safety, security and stewardship. Current UMS technological capabilities coupled with USCG mission needs motivate an analysis of proposed USCG UMS through a systems engineering methodology. This work begins by decomposing the capability needs for USCG UMS by developing a series of concepts of operations (CONOPS) in a “solution neutral” context. Following capabilities analysis, multi-mission commonalities help derive three USCG UMS alternatives: (1) Cutter-Based Tactical UUV, (2) Shore-Based Harbor/Coastal UUV/USV, and (3) Operational Offshore USV. These alternatives and their respective system architectures provide a design concept for near- to mid-term (5-10 year) acquisition. Finally, feasibility analysis reviews key system enablers (such as technology, capability, policy, and supportability and manpower) for the alternatives to justify a realistic integration timeline. Recommendations for technology investments, enhanced UMS partnerships, USCG unmanned system policies and organizational knowledge are provided to reduce delays and to accelerate delivery of needed capabilities to the field. This study lays the foundation for future strategic planning of USCG UMS (i.e., a USCG UMS Roadmap) while providing additional motivation for USCG unmanned systems in general.http://archive.org/details/asystemsengineer1094534766Outstanding ThesisLieutenant, United States Coast GuardApproved for public release; distribution is unlimited

Testing the neutrality of matter by acoustic means in a spherical resonator

New measurements to test the neutrality of matter by acoustic means are reported. The apparatus is based on a spherical capacitor filled with gaseous SF$_6$ excited by an oscillating electric field. The apparatus has been calibrated measuring the electric polarizability. Assuming charge conservation in the $\beta$ decay of the neutron, the experiment gives a limit of $\epsilon_\text{p-e}\lesssim1\cdot10^{-21}$ for the electron-proton charge difference, the same limit holding for the charge of the neutron. Previous measurements are critically reviewed and found incorrect: the present result is the best limit obtained with this technique

Exchange Monte Carlo Method and Application to Spin Glass Simulations

We propose an efficient Monte Carlo algorithm for simulating a ``hardly-relaxing" system, in which many replicas with different temperatures are simultaneously simulated and a virtual process exchanging configurations of these replica is introduced. This exchange process is expected to let the system at low temperatures escape from a local minimum. By using this algorithm the three-dimensional $\pm J$ Ising spin glass model is studied. The ergodicity time in this method is found much smaller than that of the multi-canonical method. In particular the time correlation function almost follows an exponential decay whose relaxation time is comparable to the ergodicity time at low temperatures. It suggests that the system relaxes very rapidly through the exchange process even in the low temperature phase.Comment: 10 pages + uuencoded 5 Postscript figures, REVTe

Cooperative motion and growing length scales in supercooled confined liquids

Using molecular dynamics simulations we investigate the relaxation dynamics of a supercooled liquid close to a rough as well as close to a smooth wall. For the former situation the relaxation times increase strongly with decreasing distance from the wall whereas in the second case they strongly decrease. We use this dependence to extract various dynamical length scales and show that they grow with decreasing temperature. By calculating the frequency dependent average susceptibility of such confined systems we show that the experimental interpretation of such data is very difficult.Comment: 7 pages of Latex, 3 figure

Is hail suppression useful in Serbia? – General review and new results

Anthropogenic influence on weather has been increasingly published and discussed in the last decades. Climate changes caused by inadvertent anthropogenic influence are well underway. Hail suppression, which has been proven to have no influence on weather, will be considered in the article. Even though hail suppression as scientifically ungrounded activity seemed to promise certain success several decades ago, it has spread over the whole territory of the Republic of Serbia after abundant experience, when many developed countries have given up on this activity. Reasons will be presented for the senselessness of hail suppression based on the latest research. By processing all hail data from the territory of Serbia in the period from 1967 to 2010, it was found out that the hail trend is rising which is in contrary to expectations and previous claims that hail suppression decreases hail frequency

Modelling of the Aral and Caspian seas drying out influence to climate and environmental changes

The complete drying out of the Aral and Caspian seas, as isolated continental water bodies, and their potential impact on the climate and environment is examined with numerical simulations. Simulations use the atmospheric general circulation model (ECHAM5) as well as the hydrological discharge (HD) model of the Max-Planck-Institut für Meteorologie. The dry out is represented by replacing the water surfaces in both of the seas with land surfaces. New land surface elevation is lower, but not lover than 50 m from the present mean sea level. Other parameters in the model remain unchanged. The initial meteorological data is real; starting with January 1, 1989 and lasting until December 31, 1991. The final results were analyzed only for the second, as the first year of simulation was used for the model spinning up.The drying out of both seas leads to an increase in land surface and average monthly air temperature during the summer, and a decrease of land surface and average monthly air temperature during the winter, above the Caspian Sea. The greatest difference in temperature between dry and not dry cases have the same values, about 7–8 °C in both seasons, while daily extremes of temperature are much more pronounced. In the wider local/regional area, close to both seas, drying out leads to a difference in average annual temperatures by about 1 °C. On a global scale, the average annual temperature remains unchanged and the configuration of the isotherms remain unchanged, except for over some of the continents. In winter, Central Asia becomes cooler, while over Australia, southern Africa, and South America, it becomes slightly less warm. Furthermore, a new heat island occurs in western Sahara during summer

Developing User‐Friendly Habitat Suitability Tools from Regional Stream Fish Survey Data

We developed user‐friendly fish habitat suitability tools (plots) for fishery managers in Michigan; these tools are based on driving habitat variables and fish population estimates for several hundred stream sites throughout the state. We generated contour plots to show patterns in fish biomass for over 60 common species (and for 120 species grouped at the family level) in relation to axes of catchment area and low‐flow yield (90% exceedance flow divided by catchment area) and also in relation to axes of mean and weekly range of July temperatures. The plots showed distinct patterns in fish habitat suitability at each level of biological organization studied and were useful for quantitatively comparing river sites. We demonstrate how these plots can be used to support stream management, and we provide examples pertaining to resource assessment, trout stocking, angling regulations, chemical reclamation of marginal trout streams, indicator species, instream flow protection, and habitat restoration. These straightforward and effective tools are electronically available so that managers can easily access and incorporate them into decision protocols and presentations.Received April 9, 2010; accepted November 8, 2010Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141005/1/nafm0041.pd