Increasing attention has recently been devoted to underwater sensor networks (UWSNs) because of their capabilities in the ocean monitoring and resource discovery. UWSNs are faced with different challenges, the most notable of which is perhaps how to efficiently deliver packets taking into account all of the constraints of the available acoustic communication channel. The opportunistic routing p...

The topic of the void was of significant philosophical and scientific importance in the ancient and medieval world. Some, such as the atomists, maintained that the void was essential if one were to explain motion. Others, such as Aristotle, argued that the existence of the void would absolutely preclude the possibility of motion. Moreover, there were disputes concerning even how to characterize...

Void detection is challenging due to the complexity of near-surface materials and the limited resolution of geophysical methods. Although multichannel, high-frequency, surface-wave techniques can provide reliable shear (S)-wave velocities in different geological settings, they are not suitable for detecting voids directly based on anomalies of the S-wave velocity because of limitations on the r...

class Subject { private List observers = new LinkedList(); void addObserver(Observer o) { observers.add(o); } protected void notifyObservers() { for (Iterator i = observers.iterator(); i.hasNext();) { ((Observer) i.next()).update(this); } } } class ConcreteSubject extends Subject { private final Date date = new Date(); void setDate(long milli) { date.setTime(milli); notifyObservers(); } Date ge...

The initiation and propagation of a crack and an adiabatic shear band in three-dimensional finite coupled thermomechanical deformations of a homogeneous and isotropic thermoelastoviscoplastic rectangular 4340 steel plate containing a centrally located through-the-thickness elliptic void and deformed in simple tension are analyzed numerically by using thefinite element computer codeDYNA3D. Initi...

Thick composite laminates can be used in aerospace and automotive industry replacing metals for weight saving. Increasing the thickness can bring more defects, like voids. This master thesis focuses on the multi-scale voids prediction and their mechanical effect simulation of thick composite laminates manufacturing by Resin Transfer Molding (RTM). It could be potentially used in safe design of ...

A model based on the first order perturbation expansion of magnetic flux in a two-phase liquid metal flow has been developed for low magnetic Reynolds number Rem. This model takes into account the distortion of the induced eddy currents due to the presence of void in the conducting medium. Specific experiments with an eddy current flow meter have been realized for two periodic void distribution...

Based on a laser diode, a 12 × 6 photodiode array sensor, and machine learning techniques, a new void fraction measurement method for gas-liquid two-phase flow in small channels is proposed. To overcome the influence of flow pattern on the void fraction measurement, the flow pattern of the two-phase flow is firstly identified by Fisher Discriminant Analysis (FDA). Then, according to the identif...

In process industries, the measurement of void fraction is considerably important for sustainable operations. The erroneous calculation of void fraction is inevitably be the cause of many industrial accidents such as loss of coolant accidents in reactor operations, sweet corrosions in sub-sea oil and gas pipelines and an in-efficient process control of chemical plants. Keeping in view the impor...

Mobile underwater sensor networks are usually featured with three-dimensional topology, high node mobility and long propagation delays. For such networks, geographic routing has been shown to be very suitable. However, routing voids pose great challenges on the greedy policy used in most geographic routing protocols. The problem is more severe for underwater sensor networks because of node mobi...