Improved beamforming performance using pulsed plane wave decomposition

A tool for calculating the beamformer setup associated with a specified pulsed acoustic field is presented. The method is named Pulsed Plane Wave Decomposition (PPWD) and is based on the decomposition of a pulsed acoustic field into a set of PPWs at a given depth. Each PPW can be propagated to the location of the elements of an array transducer by a time delay. The contribution of each propagated PPW is summed to form one time function for each array element (the BMF matrix). This approach gives the beamformer setup needed to obtain a close approximation to the desired bounded pulsed acoustic field without involving any optimization scheme. The approximation arises due to the limited size of the acoustic aperture and the spatial sampling property of the array transducer. Thus, the acoustical field can be designed according to the imaging needs. The method is demonstrated by examples in the 2D space by analytical equations, simulation, and experimental results

Performance of a vector velocity estimator

It is a well-known limitation of all commercially available scanners that only the velocity component along the propagation direction of the emitted pulse is measured, when evaluating blood velocities with ultrasound. Proposals for solving this limitation using several transducers or speckle tracking can be found in the literature, but no method with a satisfactory performance has been found that can be used in a commercial implementation. A method for estimation of the velocity vector is presented. Here an oscillation transverse to the ultrasound beam is generated, so that a transverse motion yields a change in the received signals. The method uses two ultrasound beams for sampling the in-phase and quadrature component of the lateral field, and a set of samples (in-phase and quadrature in both time and space) are taken for each pulse-echo line. These four samples are then used in an autocorrelation approach that yields both the axial and the lateral velocity, and thus the velocity ve..

Consumption: From Cradle to Grave

Exploration and understanding of how children are conceptualized as consumers through corporate branding in Western and Northern Europe. This research identifies the polarized debate aroung child consumerism and realizes not only brands but also families, politics and media play an important role in the developing consumption among children. This study gives a brander's perspective on the display of children in advertising and viepoint of how marketing is used in creating loyalty from early age on. But it also highlight the responsibility brands have and the focus on creating informed children on items as health, relationships, money, value and family

The Role of Logistics in Practical Levelized Cost of Energy Reduction Implementation and Government Sponsored Cost Reduction Studies: Day and Night in Offshore Wind Operations and Maintenance Logistics

This paper reveals that logistics make up at least 17% of annual operational expenditure costs for offshore wind farms. Annual operational expenditure is found to vary by a factor of 9.5, making its share of levelized cost of energy for offshore wind range from 13% to 57%. These are key findings of a 20-month research project targeting cost reduction initiatives for offshore wind systems. The findings reveal that cost-out measures are difficult to implement due to cultural differences. Implementation efforts are rendered by personnel located offshore in a harsh sea environment which is in stark contrast to the shore-based office personnel who develop studies directing cost reduction efforts. This paper details the company motivation to join industry-wide cost reduction initiatives. A business case for offshore wind operations and maintenance logistics yielding 1% savings in levelized cost of energy is included on how to expand working hours from daytime to also work at night

EU og Ukraine: Muligheder mod øst

Siden murens fald har EU engageret sig i Ukraine. Krisen i det store land mod øst har tydeligjort hvor vigtig EUs østlige grænse er, ikke kun sikkerhedspolitisk, men også i forhold til menneskerettigheder