Stevens Institute of Technology

About: Stevens Institute of Technology is a education organization based out in Hoboken, New Jersey, United States. It is known for research contribution in the topics: Cognitive radio & Wireless network. The organization has 5440 authors who have published 12684 publications receiving 296875 citations. The organization is also known as: Stevens & Stevens Tech.

I-SEP: An Improved Routing Protocol for Heterogeneous WSN for IoT-Based Environmental Monitoring

Abstract: Wireless sensor networks (WSNs) is a virtual layer in the paradigm of the Internet of Things (IoT). It inter-relates information associated with the physical domain to the IoT drove computational systems. WSN provides an ubiquitous access to location, the status of different entities of the environment, and data acquisition for long-term IoT monitoring. Since energy is a major constraint in the design process of a WSN, recent advances have led to project various energy-efficient protocols. Routing of data involves energy expenditure in considerable amount. In recent times, various heuristic clustering protocols have been discussed to solve the purpose. This article is an improvement of the existing stable election protocol (SEP) that implements a threshold-based cluster head (CH) selection for a heterogeneous network. The threshold maintains uniform energy distribution between member and CH nodes. The sensor nodes are also categorized into three different types called normal, intermediate, and advanced depending on the initial energy supply to distribute the network load evenly. The simulation result shows that the proposed scheme outperforms SEP and DEEC protocols with an improvement of 300% in network lifetime and 56% in throughput.

Surface complexation of organic arsenic on nanocrystalline titanium oxide.

Abstract: The adsorption mechanisms of monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) on nanocrystalline titanium oxide (TiO2) were investigated with X-ray absorption spectroscopy (XAS), surface charge and zeta potential measurements, adsorption edge, and surface complexation modeling. XAS data demonstrated that MMA and DMA formed bidentate and monodentate inner sphere complexes with the TiO2 surface, respectively. The charge and zeta potential behaviors of TiO2 as a function of ionic strength suggested that the point of zero charge (PZC) and isoelectric point (IEP) of TiO2 were identical at pH 5.8. Adsorption of MMA and DMA on TiO2 shifted the IEP to pH 4.1 and 4.8, respectively, indicating the formation of negatively charged surface complexes. A satisfactory interpretation of the experimental data was provided by the charge distribution (CD) multi-site complexation (MUSIC) model with the triple plane option under the constraint of the XAS evidence.

Theory of negative differential conductivity in a superlattice miniband.

Abstract: Bloch equation conductivity perpendicular to the layers of a superlattice (period d) is evaluated using an extension of the balance-equation approach [X. L. Lei and C. S. Ting, Phys. Rev. B 32, 1112 (1985)] to narrow-band transport. The perpendicular peak drift velocity ${\mathit{v}}_{\mathit{p}}$ and the critical field ${\mathit{E}}_{\mathit{c}}$, at which the drift velocity peaks, are analyzed as functions of miniband width. Our theoretical prediction that ${\mathit{E}}_{\mathit{c}}$d increases with decreasing miniband width agrees well with the data of Sibille et al. [Phys. Rev. Lett. 64, 52 (1990)], even for the samples of narrowest miniband width in their experiment.