Xianglong Yang

A Wireless Design of Low-Cost Irrigation System Using ZigBee Technology

At present, labor-saving and water-saving technology is a key issue in irrigation. A wireless solution for intelligent field irrigation system dedicated to Jews-ear planting in Lishui, Zhejiang, China, based on ZigBee technology was proposed in this paper. Instead of conventional wired connection, the wireless design made the system easy installation and maintenance. The hardware architecture and software algorithm of wireless sensor/actuator node and portable controller, acting as the end device and coordinator in ZigBee wireless sensor network respectively, were elaborated in detail. The performance of the whole system was evaluated in the end. The long-time smooth and proper running of the system in the field proved its high reliability and practicability. As an explorative application of wireless sensor network in irrigation management, this paper offered a methodology to establish large-scale remote intelligent irrigation system.

Plume Source Localizing in Different Distributions and Noise Types Based on WSN

Accidental gas leaks from unknown sites will cause the serious environmental pollution. One of the efficient methods to solve the problem is tracking and locating the plume source position. This paper presents a wireless sensor network installed with the gas sensor to on-line monitor the environment and estimate the location of a gas source based on the concentration readings at the wireless sensor nodes. Nonlinear Least Squares Method (NLS) was proposed for localization. The effect of the estimation error, with different distributions of the sensor nodes, different sensor number and different types of the back ground noises, is researched by simulations. The simulation results show that when the number of the nodes is more, the effect of the different distributions is not distinct. While the number of the nodes is less, the estimation error under the uniform distribution is more stable than under the random distribution. The suitable deployed method is discussed based on the simulation results. We also discussed the impact of the different noise types to the estimation error.

Capacitive monitoring of the antigen-antibody reactions enhanced by nanogold

An immunosensor for measuring antigen-antibody binding by nanogold particles enhancement was presented here. A gold plate electrode was modified by a SAM (self-assembled monolayer) of 11-mercaptoundecanioc acid. Then sheep anti-rabbit IgG was immobilized onto the end of the 11-mercaptoundecanioc acid. With that the gold electrode was exposed to the mixed solution of rabbit IgG and nanogold labeled sheep anti-rabbit IgG. The differential capacitance of the electrical double layer was monitored to detect the antigen-antibody reaction. The result showed the capacity of the electrical double layer by nanogold enhancement was largely increased compared to that in traditional capacitive immunosensor. The detection sensitivity is up to 10nF/mug/ml

Development of a novel electronic tongue system using sensor array based on polymer films for liquid phase testing

A novel electronic tongue system had been developed recently in our labs, which was based on impedance measurements of a hybrid sensor array of different polymer films either conjugated conducting polymers (CPs) or rendered conductive polymers by the addition of carbon black (CB) or single wall carbon nanotubes (CNT). In this work, preliminary experiments were carried out on a series of measurements of liquids containing different concentrations of acid (HCl), salt (NaCl), glucose, ethanol and a bitter substance (sodium dehydrocholate).The impedance data have been processed using principal component analysis(PCA) algorithm. The preliminary results demonstrate the feasibility of artificial taste sensing using the polymer films sensory array

Novel Shear-horizontal Surface Acoustic Wave Based Immunosensors Using SiO 2 Waveguiding Layers And Flow Injection Analysis

Surface acoustic wave (SAW) devices based on shear-horizontal (SH) waves can be used as mass-sensitive immunosensors. This paper presents a novel SH-SAW sensor to detect anti-immunoglobulin (IgG) molecules by means of the antibody-antigen binding mechanism. The sensor system comprising dual delay lines was fabricated on 36° Y-X LiTaO3substrate. A SiO2layer was used as love mode waveguiding layers, well as insulating and chemically resistant protective layer. Moreover, flow injection analysis (FIA) method was used for continuous detection the protein molecules. The protein A was immobilized on the optional surface of the gold layer, then coupled with IgG to adsorb the antigens to be measured in the protein solution. The operational frequency of the system changed due to the interaction of antibody-antigen binding. The experimental result demonstrates the sensor has stable frequency response to the mass loading effect of the various anti-IgG concentrations with the sensitivity up to 3.3ng/ml/Hz.