Abstract: A method for imaging a volume of tissue in a scan region, including: emitting, from transmitting transducers, acoustic waveforms toward the volume of tissue; detecting, with detecting transducers, a plurality acoustic signals derived from acoustic waveforms interacting with the volume of tissue; generating from the detected acoustic signals a plurality of variable attenuation maps, in which each variable attenuation map corresponds to acoustic signals detected by a respective detecting transducer and includes a plurality of variable attenuation coefficients mapped to the scan region; modifying at least a portion of the detected acoustic signals based on one or more variable attenuation maps; and generating a reflection rendering of the volume of tissue based on the modified acoustic signals.

Abstract: It is disclosed an acoustic tomography method to improve the time of flight estimation, said method comprising the steps of: sequentially triggering a set of N transmitters so as to generate a sequence of N acoustic waves through a volume being scanned; receiving each of said acoustic waves after transmission through said volume with a set of M receivers, which are called received signals; delaying by varying delays the N different said received signals that each receiver receives from the N different transmitters, and adding them together to form a new received signal, which is called transmit-beamformed signal for that receiver; delaying by varying delays the M different said transmit-beamformed signals for each receiver and adding them together at each receiver to form a new signal, which we call transmit-receive-beamformed signal.

Abstract: An iterative method for calibrating a transducer array characterized by calibration parameters, based on time delay measurements between transducer pairs, comprising the steps of: creating a distance data set that includes pairwise distances between estimated positions of transducer; forming a time delay measurement data set that includes time delay measurements between transducer pairs; generating from the time delay measurement data set an estimate of at least one calibration parameter; modifying the time delay measurement data set and the distance data set based on the estimated calibration parameters; denoising the modified distance data set with an iterative algorithm; updating the estimated positions of transducers based on the denoised modified distance data set; and repeating at least a portion of the steps until the difference between the estimated positions of transducer pairs and updated estimated positions of transducers satisfies a stopping criterion.

Abstract: A method for imaging a volume of tissue in a scan region, including: emitting, from transmitting transducers, acoustic waveforms toward the volume of tissue; detecting, with detecting transducers, a plurality acoustic signals derived from acoustic waveforms interacting with the volume of tissue; generating from the detected acoustic signals a plurality of variable attenuation maps, in which each variable attenuation map corresponds to acoustic signals detected by a respective detecting transducer and includes a plurality of variable attenuation coefficients mapped to the scan region; modifying at least a portion of the detected acoustic signals based on one or more variable attenuation maps; and generating a reflection rendering of the volume of tissue based on the modified acoustic signals.

Abstract: The present invention relates to dispersants such as superplasticizers for hydratable cementitious compositions, and more particularly to methods for achieving variable degrees of longer slump life in concrete and mortar without loss of stability. This is achieved by using two admixture systems. The first admixture composition has multi-components for achieving initial-slump-enhancement, later-slump-retention, and limiting initial slump. The second admixture composition has the later-slump-enhancing component. Alternatively, conventional water reducers or superplasticizers can be employed initially, followed by the later-slump-enhancing admixture composition.

Abstract: An iterative method for calibrating a transducer array characterized by calibration parameters, based on time delay measurements between transducer pairs, comprising the steps of: creating a distance data set that includes pairwise distances between estimated positions of transducer; forming a time delay measurement data set that includes time delay measurements between transducer pairs; generating from the time delay measurement data set an estimate of at least one calibration parameter; modifying the time delay measurement data set and the distance data set based on the estimated calibration parameters; denoising the modified distance data set with an iterative algorithm; updating the estimated positions of transducers based on the denoised modified distance data set; and repeating at least a portion of the steps until the difference between the estimated positions of transducer pairs and updated estimated positions of transducers satisfies a stopping criterion.

Abstract: It is disclosed an acoustic tomography method to improve the time of flight estimation, said method comprising the steps of: sequentially triggering a set of N transmitters so as to generate a sequence of N acoustic waves through a volume being scanned; receiving each of said acoustic waves after transmission through said volume with a set of M receivers, which are called received signals; delaying by varying delays the N different said received signals that each receiver receives from the N different transmitters, and adding them together to form a new received signal, which is called transmit-beamformed signal for that receiver; delaying by varying delays the M different said transmit-beamformed signals for each receiver and adding them together at each receiver to form a new signal, which we call transmit-receive-beamformed signal.

Abstract: The present invention relates to dispersants such as superplasticizers for hydratable cementitious compositions, and more particularly to methods for achieving variable degrees of longer slump life in concrete and mortar without loss of stability. This is achieved by using two admixture systems. The first admixture composition has multi-components for achieving initial-slump-enhancement, later-slump-retention, and limiting initial slump. The second admixture composition has the later-slump-enhancing component. Alternatively, conventional water reducers or superplasticizers can be employed initially, followed by the later-slump-enhancing admixture composition.

Abstract: Methods for making stretch blow molded polypropylene articles and preforms used to produce the polypropylene stretch blow molded articles are provided. In certain embodiments, the articles are produced with stretch blow molding processes using composite stretch ratios of less than or equal to 6. The blow molded articles may be bottles. In certain embodiments, the preforms for producing the blow molded articles have a maximum axial dimension that is at least 35% of the axial dimension of the blow molded article and a maximum radial dimension that is at least 35% of the maximum radial dimension of the blow molded article.