Point absorber wave energy converters in regular and irregular waves with time domain analysis

A discrete control of latching is used to increase the bandwidth of the efficiency of the Wave Energy Converters (WEC) in regular and irregular seas. When latching control applied to WEC it increases the amplitude of the motion as well as absorbed power. It is assumed that the exciting force is known in the close future and that body is hold in position during the latching time. A heaving vertical-cylinder as a point-absorber WEC is used for the numerical prediction of the different parameters. The absorbed maximum power from the sea is achieved with a three-dimensional panel method using Neumann-Kelvin approximation in which the exact initial-boundary-value problem is linearized about a uniform flow, and recast as an integral equation using the transient free-surface Green function.The calculated response amplitude operator, absorbed power, relative capture width, and efficiency of vertical-cylinder compared with analytical results

Person to Person in Costa Rica

While still in the midst of their study abroad experiences, students at Linfield College write reflective essays. Their essays address issues of cultural similarity and difference, compare lifestyles, mores, norms, and habits between their host countries and home, and examine changes in perceptions about their host countries and the United States. In this essay, Kara Barlow describes her observations during her study abroad program at Centro Cultural e Histórico José Figueres Ferrer, in San Ramón, Costa Rica

Pet Therapy Use in Pediatric Hospitals: an Internet Based Pilot Study

Introduction: In a technologically advanced health care system, health care providers continue to care for the physical, emotional, and spiritual well being of their patients. Alternative therapies, such as massage, music, and aroma therapy, are often included in such holistic care. Pet therapy is another form of alternative therapy that appears to be beneficial. Method: Child life coordinators and play therapists from 100 pediatric hospitals in 44 U.S. states were sent an email invitation to participate in the study by completing an online survey. Results: From the children\u27s hospitals responding, it appears that pet therapy is used in the majority of the settings, and with most age groups, excluding infants. The majority of respondents had favorable attitudes towards pet therapy, although the preliminary data show a lack of knowledge about pet therapy among health care providers. Discussion: Pet therapy is used in various hospital settings; more research is required to provide data that support the effects of pet therapy use with hospitalized children

Multibody interactions of floating bodies with time domain predictions

The applications of the three-dimensional transient panel code ITU-WAVE based on potential theory is further extended to take into account the multibody interactions in an array system using linear and square arrays. The transient wave-body interactions of first-order radiation and diffraction hydrodynamic parameters are solved as the impulsive velocity potential to predict Impulse Response Functions (IRFs) for each mode of motion. It is shown that hydrodynamic interactions are stronger when the bodies in an array system are close proximity and these hydrodynamic interactions are reduced considerably and shifted to larger times when the separation distances are increased. The numerical predictions of radiation (added-mass and damping coefficients) and exciting (diffraction and Froude-Krylov) forces are presented on each floating bodies in an array system and on single structure considering array as single floating body. Furthermore, the numerical experiment shows the hydrodynamic interactions are more pronounced in the resonant frequency region which are of important for fluid forces over bodies, responses and designs of multibody floating systems. The present numerical results of ITU-WAVE are validated against analytical, other numerical and experimental results for single body, linear arrays (two, five and nine floating bodies) and square arrays of four truncated vertical cylinders

Control of Wave Energy Converters for Maximum Power Absorption with Time Domain Analysis

A discrete control of latching is used to increase the bandwidth of the efficiency of the Wave Energy Converters (WEC) in regular and irregular seas. When latching control applied to WEC it increases the amplitude of the motion as well as absorbed power. It is assumed that the exciting force is known in the close future and that body is hold in position during the latching time. A heaving vertical-cylinder as a point-absorber WEC is used for the numerical prediction of the different parameters. The absorbed maximum power from the sea is achieved with a three-dimensional panel method using Neumann-Kelvin approximation in which the exact initial-boundary-value problem is linearized about a uniform flow, and recast as an integral equation using the transient free-surface Green function. The calculated response amplitude operator, absorbed power, relative capture width, and efficiency of vertical-cylinder compared with analytical results