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Social work education in Africa is faced with a myriad of challenges that require immediate attention for a sustainable future. If the principles of social justice, human rights and respect for diversities are central to the social work profession, then the education and practice of social work in Nigeria should be culturally relevant in engaging people and structures to address challenges. Participants for the study included four social work educators, 10 social work students and four social work practitioners. Findings from the research suggest the need for a paradigm shift from Western pedagogy to a more inclusive Nigerian pedagogy for a sustainable future.

Social work education in Africa is faced with a myriad of challenges that require immediate attention for a sustainable future. If the principles of social justice, human rights and respect for diversities are central to the social work profession, then the education and practice of social work in Nigeria should be culturally relevant in engaging people and structures to address challenges. Participants for the study included four social work educators, 10 social work students and four social work practitioners. Findings from the research suggest the need for a paradigm shift from Western pedagogy to a more inclusive Nigerian pedagogy for a sustainable future.

The demand for more accurate tropical cyclone (TC) forecasts with longer lead times is greater than ever due to the enormous economic and societal impact of these storms. There has been spectacular improvement in TC track prediction; a three-day hurricane track forecast today is as skillful as a one-day forecast was just 30 years ago. However, there has been little progress in improving TC intensity and structure forecasts due to a variety of reasons, ranging from a lack of critical observations under high wind conditions and in the TC environment, to inaccurate representations of TC physical processes in numerical weather prediction (NWP) models. Advances in high-resolution TC modeling and data assimilation are thought to be necessary to significantly improve the performance of intensity and structure prediction. To this end, the Naval Research Laboratory in Monterey, California, has developed the Coupled Ocean/Atmosphere Mesoscale Prediction System for Tropical Cyclones (COAMPS-TC ), a new version of COAMPS designed specifically for highigh-resolutionopical cyclone prediction.

A new version of the Coupled Ocean/Atmosphere Mesoscale Prediction System for Tropical Cyclones (COAMPS-TC TM ) has been developed specifically for forecasting tropical cyclone track, structure, and intensity. The COAMPS-TC has been tested in real-time in both coupled and uncoupled modes over the past several tropical cyclone seasons in the Pacific and Atlantic basins at a horizontal grid spacing of 5 km. An evaluation of a large sample of real-time forecasts for the 2010 and 2011 seasons in the Atlantic basin reveals that the COAMPS-TC predictions have smaller intensity errors than other real-time dynamical models for forecasts beyond the 30 h time. Real-time forecasts for Hurricane Irene (2011) illustrate the capability of the model to capture both the intensity and the fine-scale features (e.g., eyewall, rainbands), in agreement with observations. The results of this research highlight the promise of high-resolution deterministic and ensemble-based approaches for tropical cyclone prediction using COAMPS-TC., Published in Advances in Geosciences, v28 p15-28, 2011. Sponsored in part by NOAA and the DoD Supercomputing Resource Center, Stennis, MS. Prepared in collaboration with the Naval Research Laboratory, Stennis, MS. Prepared in cooperation with SAIC, Monterey, CA.

The objective of this study was to record maximum dolphin swimming speeds sustainable for several seconds with free-ranging and captive dolphins utilizing different motivational strategies. Recordings were used to determine relationships between the various kinematic parameters, particularly the Strouhal number, which characterizes dolphin swimming motion. Comparisons are made, where possible, with results from previous studies.

Passive control of shear flow is used to control the rate of mixing and stability of submerged gaseous jets in liquids. The object is to evaluate the effectiveness of recently developed shear flow control techniques for application to gaseous jets injected into liquids and ultimately to apply these techniques to gaseous oxidants injected into liquid metal fuels. These control techniques have been initially tested in nonreacting gas/liquid systems. A large increase in degree of mixing and jet stability occurs when non-axisymmetric nozzles are used as injectors relative to injection by axisymmetric Fanno tube type nozzles. Jet volume spreading rate is increased by a factor of 4. A characteristic instability (the 'reverse shock' or reverse flow effect) occurring in such two-phase systems is greatly reduced by passive control of the shear flow. A simple passive technique of controlling entrainment is described which is effective in eliminating the reverse flow effect. The relevance of these control techniques to liquid metal combustion is discussed. Flow visualization, Modeling, Combustion, Control/CLMC, Passive control, Liquid metal combustion

Active control of complex imposes unique requirements for physical models and feedback control strategies. Physical models which are adequate to predict the influence of actuators must be coupled with feedback control approaches suitable for use when system characteristics are incompletely specified a priori and change with time. The present paper describe laboratory scale experiments in which turbomachinery surge and stall and combustion instabilities are successfully attenuated by active means. Work which has been conducted in parallel to develop improved models and control strategies to realize fault tolerant active control of such systems in the full scale operational environment is also discussed., Pres. at the International Gas Turbine and Aeroengine Congress and Exposition, held in Cologne, Germany on 1-4 Jun 1992. Pub. in Transactions of the American Society of Mechanical Engineers, 92-GT-35, p1-9, Sep 1992.

A direct numerical simulation of the Navier-Stokes equations of a feedback controlled cylinder wake flow at the Reynolds number of 60 is presented. The simulation shows that vortex shedding behind a circular cylinder is suppressed to a significant degree by applying a feedback forcing with an appropriate phase via blowing/suction slots located at +/-110 deg from the leading edge. Depending on the phase of the feedback forcing relative to the vortex shedding phase, the shedding of the vortices is either suppressed (stabilized) or further enhanced (destabilized). Active control, Torpedo., Pub. in DSC-Vol. 38, Active Control of Noise and Vibration, ASME, p59-64 1992.

Oscillation of fuel composition in ducted air flows with oscillatory injection of gaseous fuel was studied using temperature difference as scalar in flows involving radial injection of an oscillatory fuel jet and radial and axial injection of a steady air-fuel jet with oscillatory fuel composition into a ducted air stream. Local measurements of mean and oscillatory velocity and scalar in turbulent flow were carried out with flow rates, frequency and amplitude of imposed oscillations as variables. The decay of the oscillation of the scalar was faster than that of mean velocity and mean scalar, and attenuation was strongest in the shear layer. Flow past a bend attenuated oscillations by around 40% and past a bluff-body downstream of a jet resulted in faster decay of oscillations than in flows without a bluff-body. The influences of frequency in the range between 100 and 200 Hz and mass flow ratio of cross flow to jet between 5 and 15 on attenuation of oscillations was small. Active Control, Torpedo

The effect of a tethered polymer coating on the turbulence production in a turbulent boundary layer was examined. An experimental investigation was carried out in the Naval Ocean Systems Center (NOSC) water tunnel. The aims of the study were to determine the existence of an interaction between the tethered polymer coating and turbulence production at the wall and in the outer layer. Skin friction was measured in a flat plate turbulent boundary layer with and without tethered polymer coating. There were no measurable effects on the turbulent boundary layer skin friction. We should point out the purpose of the tethered polymer coatings is the prevention of biofouling on ships. With this fact in mind it is encouraging that the coating has no deleterious effect on the boundary layer.