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In order to prevent hydrofoil colliding with cetaceans, the underwater speaker (UWS) has been installed to repel cetaceans. Yamada et al. (2012) analyzed and devised the UWS sound as it fits the cetaceans' acoustic properties to prevent the collision furthermore. The new UWS sound was devised and synthesized by Yamada et al. (2015) with expectation of avoiding collision with large cetaceans (Patent applied for, JP2014-171411). In this research project, the new UWS sound was investigated by the playback experiment on humpback whale (Megaptera novaeangliae) and by sighting survey in the actual hydrofoil shipping service route. As a result, a physiological and behavioral change of the humpback whale was observed in the playback experiment of the new UWS sound, and the chance of hydrofoil encountering cetaceans of the new UWS sound was smaller than that of the previous UWS sound. Therefore, the improvement of the new UWS sound was confirmed. Lastly, we wish this research project would contribute toward the safer cruise of hydrofoil in the future. [ABSTRACT FROM AUTHOR]

When handling a vehicle trajectory dataset composed of a large number of points on a digital map, all the collected data may not be required. In particular, when a trajectory is displayed on a computer screen, it is desirable to use the smallest dataset that can accurately describe the actual trajectory. The objective of this study is to develop an algorithm that reduces the amount of vehicle tracking data while retaining the original shape of the vehicle trajectory. The algorithm assigns a degree of importance in shape representation to each data point. The degree of importance is defined in terms of wavelet coefficients, and the algorithm determines the order by which data points are eliminated. To evaluate the performance of the algorithm, a 15,618-point dataset obtained from a GPS unit mounted on an agricultural vehicle was processed. Even when the dataset was reduced to 912 points, which is only 5.8% of the original dataset, the root mean square error was no more than 0.76 m. The computational time for data reduction on the selected computer was 8 ms. The proposed reduction algorithm was embedded in the map software used to display the vehicle trajectory. [ABSTRACT FROM AUTHOR]

The aim of this research was to establish an inexpensive and extremely accurate positioning system. This report focuses on a global positioning system (GPS) velocity sensor, which consists of a low-cost single-frequency GPS receiver and a single-board computer. Its dynamic performance was confirmed and the possibility of using it for positioning is discussed through fixture and on-vehicle tests. The GPS velocity sensor measured velocity accurately. Velocity was measured more accurately with the GPS velocity sensor than with real-time kinematic GPS throughout the fixture and on-vehicle tests. More than 90% of the error in speed was less than 0.05m/s according to the fixture test. Also, more than 70% of the error was less than 2.87°. It was also possible to determine position by integrating velocity from the GPS velocity sensor. Although accumulating and irregular errors were observed, the accuracy of positioning was higher than with differential GPS after irregular errors were compensated for. Problems for further study to reduce error are how to cancel out accumulated errors and how to initially determine the absolute position. [Copyright &y& Elsevier]

We investigated the polymorphic CAG-repeat distribution and the X-inactivation status of the human androgen receptor (HUMARA) gene in 58 female Japanese volunteers. Polymerase chain reaction amplification was performed using a fluorescent-dye-labeled primer under conditions specific for GC-rich targets, and fragments were analyzed. To estimate the length of these fragments, FAM-labeled (blue fluorescent) products were simultaneously compared with ROM-labeled size markers (red) that were created by sequencing various HUMARA fragments. The number of polymorphic CAG repeats of HUMARA in 116 alleles from 58 female subjects ranged from 15 to 28. Of the 58 volunteers, 51 (88.0%) were heterozygous. In 96% of the heterozygous female subjects, the allelic differences were no greater than 6 repeats. X-chromosome inactivation was calculated as the ratio of the area of the smaller peak to the sum of the areas of the smaller and larger peaks. The average ratio was 0.38 (range, 0.09-0.50). Preferential use of 1 allele, by more than 75% (ratio. <0.25). was observed in 5 volunteers (10.9%). The clonal nature of a patient with chronic myelogenous leukemia was easily identified. This method is sensitive enough to discriminate a difference of 1 triplet repeat. [ABSTRACT FROM AUTHOR]