In this work, a slotted patch antenna is employed as a wireless sensor for monitoring structural strain and fatigue crack. Using antenna miniaturization techniques to increase the current path length, the footprint of the slotted patch antenna can be reduced to one quarter of a previously presented folded patch antenna. Electromagnetic simulations show that the antenna resonance frequency varie...

UNLABELLED Misfit at the abutment-prosthetic cylinder interface can cause loss of preload, leading to loosening or fracture of gold and titanium screws. OBJECTIVES To evaluate the influence of screw type, alloy, and cylinder position on marginal fit of implant frameworks before and after laser welding. METHODS After Estheticone-like abutments were screwed to the implants, thirty plastic pro...

The ex situ lift out (EXLO) adhesion forces are reviewed and new applications of EXLO for focused ion beam (FIB)-prepared specimens are described. EXLO is used to manipulate electron transparent specimens on microelectromechanical systems carrier devices designed for in situ electron microscope analysis. A new patented grid design without a support film is described for EXLO. This new slotted g...

Acoustic underwater wireless sensor networks (UWSN) have recently gained attention as a topic of research. Such networks are characterized by increased uncertainty in medium access due not only to when data is sent, but also due to significantly different propagation latencies from spatially diverse transmitters—together, we call these space-time uncertainty. We find that the throughput of slot...

The problems of identifying a set of tagged objects simultaneously in an RFID network have hampered the adoption of RFID universally. When multiple tags transmit their IDs in a single period of time to a single reader over a shared wireless channel, the tag signals may collide. This collision will disturb the reader’s identification process. Hence, we proposed a modified version of Accelerated ...

Slotted Aloha is an effective random access protocol and can also be an important element of more advanced media access protocols. This paper investigates slotted Aloha in a radio environment with multiple access points. Specifically, we examine the impact of multi-access-point (multi-AP) diversity on the performance of slotted Aloha. The paper considers both omni-directional (OM) and beamformi...

We consider the problem of stability of slotted ALOHA for a system consisting of N users communicating with a common receiver, which employs spatial diversity to receive multiple transmissions simultaneuosly. We introduce a general packet reception model to incorporate multiple packet receptions since the collision channel model is no longer valid in such a scenario. We characterize the stabili...

The throughput and delay characteristics of a landmobile satellite channel are analyzed for both slotted ALOHA and slotted direct-sequence CDMA (code division multiple access), using binary phase shift keying (BPSK) modulation and forward error correction coding (FEC). In the case of CDMA, the application of path diversity techniques-maximal ratio combining and selection diversity-is also taken...

The random access protocols with multi packet reception (MPR), which include both slotted-Aloha and slotted τ-persistent CSMA protocols. For both protocols, each node makes a transmission attempt in a slot with a given probability. The transmission channel is divided into equal slot using slottedAloha, then CSMA is used to check whether the channel is idle or not. CSMA is used to avoid collisio...

There is unbalanced magnetic pull between the rotor and stator of the cage induction motor when the rotor is not concentric with the stator. These forces depend on the position and motion of the center point of the rotor. In this paper, the linearity of the forces in proportion to the rotor eccentricity is studied numerically using time-stepping finite element analysis. The results show that us...