Shenzhen University

About: Shenzhen University is a education organization based out in Shenzhen, China. It is known for research contribution in the topics: Computer science & Laser. The organization has 28054 authors who have published 35378 publications receiving 522023 citations.

A Novel Dual-Band, Dual-Polarized, Miniaturized and Low-Profile Base Station Antenna

Abstract: In this paper, a novel dual-band, dual-polarized, miniaturized and low-profile base station antenna operating in the frequency bands of 820–960 and 1710–2170 MHz is designed. Elements are arranged such that high-frequency elements are embedded in low frequency elements to reduce volume. A baffle is used to reflect the transmitted power density in the forward direction and also improve isolation between elements. Therefore, surrounding isolation baffles and rectangular baffles are appended around high-frequency elements and low-frequency elements, respectively. The diameter of the proposed antenna cover is only 200 mm, which is smaller than the existing antenna diameter of 280 mm. Compared with the other commonly used antennas, the proposed antenna also has some advantages such as concealment and low profile using a tubular form of radome, which can easily integrate the proposed antenna with the surrounding environment. The measured results verify that the proposed antenna meets the stringent design requirements: voltage standing wave ratio (VSWR) is less than 1.3, the isolation is greater than 30 dB, and the pattern parameters also meet telecommunications industry standards.

Software Defined Machine-to-Machine Communication for Smart Energy Management

Abstract: The successful realization of smart energy management relies on ubiquitous and reliable information exchange among millions of sensors and actuators deployed in the field with little or no human intervention. This motivates us to propose a unified communication framework for smart energy management by exploring the integration of software-defined networking with machine-to-machine communication. In this article, first we provide a comprehensive review of the state-of-the-art contributions from the perspective of software defined networking and machineto- machine integration. Second, the overall design of the proposed software-defined machine-to-machine (SD-M2M) framework is presented, with an emphasis on its technical contributions to cost reduction, fine granularity resource allocation, and end-to-end quality of service guarantee. Then a case study is conducted for an electric vehicle energy management system to validate the proposed SD-M2M framework. Finally, we identify several open issues and present key research opportunities.

A highly efficient degradation mechanism of methyl orange using Fe-based metallic glass powders.

Abstract: A new Fe-based metallic glass with composition Fe76B12Si9Y3 (at. %) is found to have extraordinary degradation efficiency towards methyl orange (MO, C14H14N3SO3) in strong acidic and near neutral environments compared to crystalline zero-valent iron (ZVI) powders and other Fe-based metallic glasses. The influence of temperature (294–328 K) on the degradation reaction rate was measured using ball-milled metallic glass powders revealing a low thermal activation energy barrier of 22.6 kJ/mol. The excellent properties are mainly attributed to the heterogeneous structure consisting of local Fe-rich and Fe-poor atomic clusters, rather than the large specific surface and strong residual stress in the powders. The metallic glass powders can sustain almost unchanged degradation efficiency after 13 cycles at room temperature, while a drop in degradation efficiency with further cycles is attributed to visible surface oxidation. Triple quadrupole mass spectrometry analysis conducted during the reaction was used to elucidate the underlying degradation mechanism. The present findings may provide a new, highly efficient and low cost commercial method for azo dye wastewater treatment.