NETWORKED MICROGRID OPTIMIZATION AND ENERGY MANAGEMENT

Military vehicles possess attributes consistent with a microgrid, containing electrical energy generation, storage, government furnished equipment (GFE), and the ability to share these capabilities via interconnection. Many military vehicles have significant energy storage capacity to satisfy silent watch requirements, making them particularly well-suited to share their energy storage capabilities with stationary microgrids for more efficient energy management. Further, the energy generation capacity and the fuel consumption rate of the vehicles are comparable to standard diesel generators, for certain scenarios, the use of the vehicles could result in more efficient operation. Energy management of a microgrid is an open area of research especially in generation constrained scenarios where shedding of low-priority loads may be required. Typical metrics used to assess the effectiveness of an energy management strategy or policy include fuel consumption, electrical storage energy requirements, or the net exergy destruction. When considering a military outpost consisting of a stationary microgrid and a set of vehicles, the metrics used for managing the network become more complex. For example, the metrics used to manage a vehicle’s onboard equipment while on patrol may include fuel consumption, the acoustic signature, and the heat signature. Now consider that the vehicles are parked at an outpost and participating in vehicle-to-grid power-sharing and control. The metrics used to manage the grid assets may now include fuel consumption, the electrical storage’s state of charge, frequency regulation, load prioritization, and load dispatching. The focus of this work is to develop energy management and control strategies that allow a set of diverse assets to be controlled, yielding optimal operation. The provided policies result in both short-term and long-term optimal control of the electrical generation assets. The contributions of this work were: (1) development of a methodology to generate a time-varying electrical load based on (1) a U.S. Army-relevant event schedule and (2) a set of meteorological conditions, resulting in a scenario rich environment suitable for modeling and control of hybrid AC/DC tactical military microgrids, (2) the development of a multi-tiered hierarchical control architecture, suitable for development of both short and long term optimal energy management strategies for hybrid electric microgrids, and (3) the development of blending strategies capable of blending a diverse set of heterogeneous assets with multiple competing objective functions. This work could be extended to include a more diverse set of energy generation assets, found within future energy networks

Chronicity and Mental Health Service Utilization for Anxiety, Mood, and Substance Use Disorders among Black Men in the United States; Ethnicity and Nativity Differences.

This study investigated ethnic and nativity differences in the chronicity and treatment of psychiatric disorders of African American and Caribbean Black men in the U.S. Data were analyzed from the National Survey of American Life, a population-based study which included 1859 self-identified Black men (1222 African American, 176 Caribbean Black men born within the U.S., and 461 Caribbean Black men born outside the U.S.). Lifetime and twelve-month prevalence of DSM-IV mood, anxiety, and substance use disorders (including Bipolar I and Dysthmia), disorder chronicity, and rate of mental health services use among those meeting criteria for a lifetime psychiatric disorder were examined. Logistic regression models were employed to determine ethnic differences in chronicity, and treatment utilization for disorders. While rates of DSM-IV disorders were generally low in this community sample of Black men, their disorders were chronic and remained untreated. Caribbean Black men born in the U.S. had higher prevalence of Post-Traumatic Stress Disorder, Major Depressive Disorder, and Alcohol Abuse Disorder compared with African American men. Foreign born Caribbean Black men experienced greater chronicity in Social Phobia and Generalized Anxiety Disorder compared to other Black Men. Utilization of mental health service was low for all groups of Black Men, but lowest for the foreign born Caribbean Black men. Results underscore the large unmet needs of both African American and Caribbean Black men in the United States. Results also highlight the role of ethnicity and nativity in mental disorder chronicity and mental health service utilization patterns of Black men

Influence of Angiotensin II Subtype 2 Receptor (AT2R) Antagonist, PD123319, on Cardiovascular Remodelling of Aged Spontaneously Hypertensive Rats during Chronic Angiotensin II Subtype 1 Receptor (AT1R) Blockade

Cardiac AT2R expression is upregulated in the normal process of aging. In this study we determined the contribution of AT2R to chronic antihypertensive and remodelling effects of AT1R blockade in aged hypertensive rats. Adult (20 weeks) and senescent (20 months) spontaneously hypertensive rats (SHRs) were treated with either the AT1R antagonist, candesartan cilexetil (2 mg/kg/day), the AT2R antagonist, PD123319 (10 mg/kg/day), or a combination of the 2 compounds. Mean arterial pressure (MAP) and left ventricular volume were markedly decreased by candesartan cilexetil, however, simultaneous treatment with PD123319 had no additional effect on either parameter. Perivascular fibrosis was significantly reduced by candesartan cilexetil in aged animals only, and this effect was reversed by concomitant PD123319 administration. Vascular hypertrophy was reduced by candesartan cilexetil, and these effects were reversed by simultaneous PD123319. These results suggest that AT2R stimulation does not significantly influence the antihypertensive effect of chronic AT1R blockade, but plays a role in the regulation of vascular structure. The severe degree of cardiac perivascular fibrosis in senescent animals was regressed by AT1R blockade and this effect was reversed by simultaneous AT2R inhibition, demonstrating an antifibrotic role of AT2R stimulation in the aging hypertensive heart

Resolution dependence of turbulent structures in convective boundary layer simulations

Large-eddy simulations are performed using the UK Met Office Large Eddy Model to study the effects of resolution on turbulent structures in a convective boundary layer. A standard Smagorinsky subgrid scheme is used. As the grid length is increased the diagnosed height of the boundary layer increases and the horizontally- and temporally-averaged temperature near the surface and in the inversion layer increase. At the highest resolution, quadrant analysis shows that the majority of events in the lower boundary layer are associated with cold descending air, followed by warm ascending air. The largest contribution to the total heat flux is made by warm ascending air, with associated strong thermals. At lower resolutions, the contribution to the heat flux from cold descending air is increased and that from cold ascending air is reduced in the lower boundary layer; around the inversion layer, however, the contribution from cold ascending air is increased. Calculations of the heating rate show that the differences in cold ascending air are responsible for the warm bias below the boundary layer top in the low resolution simulations. Correlation length and time scales for coherent resolved structures increase with increasing grid coarseness. The results overall suggest that differences in the simulations are due to weaker mixing between thermals and their environment at lower resolutions. Some simple numerical experiments are performed to increase the mixing in the lower-resolution simulations and to investigate backscatter. Such simulations are successful in reducing the contribution of cold ascending air to the heat flux just below the inversion, although the effects in the lower boundary layer are weaker

Chiasma

Newspaper reporting on events at the Boston University School of Medicine in the 1960s

Optimal Robot Placement for Tasks Execution

AbstractAutomotive assembly cells are cluttered environments, including robots, workpieces, and fixtures. Due to high volumes and several product variants assembled in the same cell, robot placement is crucial to increase flexibility and throughput. In this paper, we propose a novel method to optimize the base position of an industrial robot with the objective to reach all predefined tasks and minimize cycle time: robot inverse kinematics and collision avoidance are integrated together with a derivative-free optimization algorithm. This approach is successfully used to find feasible solutions on industrial test cases, showing up to 20% cycle time improvement