Waseda University

About: Waseda University is a education organization based out in Tokyo, Japan. It is known for research contribution in the topics: Catalysis & Large Hadron Collider. The organization has 24220 authors who have published 46859 publications receiving 837855 citations. The organization is also known as: Waseda daigaku & Sōdai.

Malicious node detection in wireless sensor networks using weighted trust evaluation

Abstract: Deployed in a hostile environment, individual nodes of a wireless sensor network (WSN) could be easily compromised by the adversary due to the constraints such as limited battery lifetime, memory space and computing capability. It is critical to detect and isolate the compromised nodes in order to avoid being misled by the falsified information injected by the adversary through compromised nodes. However, it is challenging to secure the flat topology networks efficiently because of the poor scalability and high communication overhead. On top of a hierarchical WSN architecture, in this paper we proposed a novel scheme based on weighted-trust evaluation to detect malicious nodes. The hierarchical network can reduce the communication overhead between sensor nodes by utilizing clustered topology. Through intensive simulation, we verified the correctness and efficiency of our detection scheme.

Priority-Based Data Gathering Framework in UAV-Assisted Wireless Sensor Networks

Abstract: This paper proposes a novel data acquisition framework in sensor networks using an unmanned aerial vehicle (UAV) with the goal of increasing the efficiency of the data gathering efforts. To maximize the system throughput, we introduce a priority-based frame selection scheme to suppress the number of redundant data transmissions between sensor nodes and the UAV. Toward this goal, we classify the nodes inside the UAV's coverage area into different frames according to their locations. Taking advantage of the mobility of the UAV, we assign different transmission priorities to nodes in different frames. To do that, we introduce an adjustment to the contention window value used in IEEE 802.11 MAC, thereby defining a lower contention window range to the frame with higher priority (urgent area) and a higher contention window range to the frame with lower priority (less important area). The proposed framework leads to a reduction in packet collisions and, at the same time, minimizes the packet loss originated from nodes in the rear-side of the UAV when the UAV moves in the forward direction. To optimize the networks' energy consumption, we present a novel routing protocol based on the aforementioned framework. By leveraging the proposed framework and routing algorithm, we aim to reduce the transmission distances between senders and receivers. A shorter distance leads to better channel quality and energy savings, as is verified by our simulation studies and results.

Observation of Exclusive Charmonium Production and gamma gamma -> mu(+)mu(-) in p(p)over-bar Collisions at root s=1.96 TeV

Abstract: In CDF we have observed the reactions p + (p) over bar -> p + X + (p) over bar, with X being a centrally produced J/psi, psi(2S), or chi(c0), and gamma gamma -> mu(+)mu(-) in p (p) over bar collisions at root s = 1.96 TeV. The event signature requires two oppositely charged central muons, and either no other particles or one additional photon detected. Exclusive vector meson production is as expected for elastic photoproduction, gamma + p -> J/psi(psi(2S)) + p, observed here for the first time in hadron-hadron collisions. We also observe exclusive chi(c0) -> J/psi + gamma. The cross sections d sigma/dy vertical bar(y=0) for J/psi, psi(2S), and chi(c0) are 3.92 +/- 0: 25(stat) +/- 0.52(syst) nb, 0.53 +/- 0.09(stat) +/- 0.10(syst) nb, and 76 +/- 10(stat) +/- 10(syst) nb, respectively, and the continuum is consistent with QED. We put an upper limit on the cross section for Odderon exchange in exclusive J/psi production.