Non-Contact Vibro-Acoustic Object Recognition Using Laser Doppler Vibrometry and Convolutional Neural Networks.

Laser Doppler vibrometers (LDVs) have been widely adopted due to their large number of benefits in comparison to traditional contacting vibration transducers. Their high sensitivity, among other unique characteristics, has also led to their use as optical microphones, where the measurement of object vibration in the vicinity of a sound source can act as a microphone. Recent work enabling full correction of LDV measurement in the presence of sensor head vibration unlocks new potential applications, including integration within autonomous vehicles (AVs). In this paper, the common AV challenge of object classification is addressed by presenting and evaluating a novel, non-contact vibro-acoustic object recognition technique. This technique utilises a custom set-up involving a synchronised loudspeaker and scanning LDV to simultaneously remotely solicit and record responses to a periodic chirp excitation in various objects. The 864 recorded signals per object were pre-processed into spectrograms of various forms, which were used to train a ResNet-18 neural network via transfer learning to accurately recognise the objects based only on their vibro-acoustic characteristics. A five-fold cross-validation optimisation approach is described, through which the effects of data set size and pre-processing type on classification accuracy are assessed. A further assessment of the ability of the CNN to classify never-before-seen objects belonging to groups of similar objects on which it has been trained is then described. In both scenarios, the CNN was able to obtain excellent classification accuracy of over 99.7%. The work described here demonstrates the significant promise of such an approach as a viable non-contact object recognition technique suitable for various machine automation tasks, for example, defect detection in production lines or even loose rock identification in underground mines.

A prospective randomised comparative study of endoscopic band ligation versus injection sclerotherapy of bleeding internal haemorrhoids in patients with liver cirrhosis.

BACKGROUND AND STUDY AIMS: Bleeding internal haemorrhoids are common and used to be treated surgically with too many complications. Endoscopic therapy is trying to take the lead. Sclerotherapy and rubber band ligation are the candidates to replace surgical therapy especially in patients with liver cirrhosis. The aim of this study was to compare endoscopic injection sclerotherapy (EIS) to endoscopic rubber band ligation (EBL) regarding effectiveness and complications in the treatment of bleeding internal haemorrhoids in Egyptian patients with liver cirrhosis. PATIENTS AND METHODS: One hundred and twenty adult patients with liver cirrhosis and bleeding internal haemorrhoids were randomised into two equal groups; the first treated with EBL using Saeed multiband ligator, and the second with EIS using either ethanolamine oleate 5% or N-butyl cyanoacrylate. All groups were matched as regards age, sex, Child score and pre-procedure Doppler values. Patients were followed up clinically and with abdominal ultrasound/Doppler for 6 months. Endoscopic and endosonography/Doppler was done before and one month after the procedure. Pre and post-procedure data were recorded and analysed. RESULTS: Both techniques were highly effective in the control of bleeding from internal haemorrhoids with a low rebleeding [10% in the EBL group and 13.33% in the EIS group] and recurrence [20% in the EBL group 20% in the EIS group] rates. Child score had a positive correlation with rebleeding and recurrence in EIS group only. Pain score and need for analgesia were significantly higher while patient satisfaction was significantly lower in EIS compared to EBL [p<0.05]. No significant difference between ethanolamine and cyanoacrylate subgroups was found [p>0.05]. CONCLUSIONS: Both EBL and EIS were effective in the treatment of bleeding internal haemorrhoids in patients with liver cirrhosis. EBL had significantly less pain and higher patient satisfaction than EIS. EBL was also safer in patients with advanced cirrhosis.

How do people form behavioral intentions when others have the power to determine social consequences?

Much literature has suggested that people who are discriminated against or are in collectivist cultures are particularly susceptible to the social consequences of society. In the present study, the authors conducted 3 experiments to test how this factor influences attitudinal versus normative control over behaviors. First, they measured males' and females' attitudes, subjective norms, and behavioral intentions with respect to a large number of behaviors. Although between-participants analyses were mostly uninformative, within-participants analyses uncovered strong evidence that behaviors are more under attitudinal control for females than for males. Similar analyses in a crosscultural experiment involving participants from the United States, the United Kingdom, China, and Mexico support the hypothesis that behaviors are more under attitudinal control for collectivists than for individualists. Finally, experimental data collected in the United States and Saudi Arabia further support this conclusion. Taken together, the findings suggest that although social consequences are both "social" and "consequences", the latter is more important than the former.