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Two one-dimensional, steady-state numerical models are presented to evaluate the performance of direct methanol fuel cells (DMFCs) in different aspects. One model is applied to simulate the double-layered catalyst structure, which reveals to greatly reduce both cathode and anode overpotential. Another model is created to simulate the effect of methanol and oxygen concentration on power density response in DMFC. In the numerical results, it was found that a DMFC consisting of double-catalyst layer electrodes exhibited many advantages over the traditional MEA, and the performances of the single cell are enhanced.

Through the extraction of face image Gabor feature, combined with Adaboost for face recognition. According to the characteristics of high dimension Gabor, redundancy is large, the introduction of Adaboost algorithm for feature selection to reduce the dimensions of feature vector, for a large number of Gabor feature selection. At the same time ,using a single positive sample set and several negative sample sets for training method to construct a strong classifier cascade classifier. Testing results in the Yale library proves the validity of the method.

This paper presents the tracking characteristics of electromagnetic sensor. To the model of live wire magnetic field of the formula derivation, and analysis of height and horizontal distance of the electromagnetic sensor and magnetic field. Deduced from magnetic field model that the tracking characteristics of the dual-inductive electromagnetic sensor, to build a tracking model. According to the analysis of a large number of experimental data, experimental results have indicated that the tracking model was approximately linearly related to the horizontal distance.

This paper presents two kinds of direct methanol fuel cell (μDMFC) stack in planar array. The silicon-based DMFC stack is designed in a flip-flop configuration using MEMS technology, and the stainless steel stack is fabricated using stamping technology. Compared to stainless steel stack, the flip-flop silicon-based stack may reduce the connection space and lower the contact resistance between the membrane electrode assembly and the plates. The electrical characterization of this μDMFC stack was carried out by tests. The experimental results showed the prototype was able to generate an open-circuit voltage of 2.7V and a maximum power density of 2.2mW/cm2 at room temperature, demonstrating the feasibility of this new configuration. Application of μDMFC stacks as portable power sources were demonstrated using small electric devices powered by this stack.

Membrane electrode assemblies (MEA) is the key component of a direct methanol fuel cell (DMFC) and its structure and fabrication technology influenced the performance of DMFC a lot. A novel structured MEA including a hydrophilic inner thin catalyst layer and a traditional outer catalyst layer, provide higher performance. To optimize the combination of the two catalysts layer a mathematical model based on Tafel type kinetics and semi-empirical mass transport coefficient was applied. The simulation of cathode overpotential results showed a DMFC with a 5μm thick inner Pt Blk catalyst layer and an 8μm thick outer 40wt%Pt/C catalyst layer as cathode electrode was the best.

In order to determine the working conditions for direct methanol fuel cell and to gain higher performances, two one-dimensional, steady-state numerical models have been presented to evaluate the performance of direct methanol fuel cells (DMFCs) using Matlab. Genetic algorithm and direct Monte Carlo algorithm have been employed to determine the optimization operation conditions of the DMFC. The cell maximal power density has been predicted via the genetic algo- rithm. ComparinG with the direct Monte Carlo algorithm, the genetic algorithm has been found to be more efficient and useful.

A direct methanol fuel cell (DMFC) with a novel double-layer structured membrane electrode assembly (MEA) was developed and a better performance was obtained. The double catalytic layer anode is composed of a hydrophilic inner catalyst layer with PtRu black and an outer catalyst layer with PtRu/C. In the double-layer structured anode, there existed a catalyst concentration gradient and porosity gradient, resulting in good mass transfer, proton and electron conducting. Furthermore, the delamination of the catalyst layer from the membrane was also resolved because of the inner hydrophilic catalyst film. To optimize the combination of the two catalysts layer a one-dimensional model based on Tafel type kinetics and semi-empirical mass transport coefficient was applied. The simulation of anode overpotential versus PtRu Blk inner layer thickness and PtRu/C outer layer thickness results showed a direct methanol fuel cell with a 5m thick inner PtRu black catalyst layer and an 8m thick outer 40wt%PtRu/C catalyst layer as anode electrode was the best.

The aim of this research is to investigate the feasibility of developing a traffic load detector system for the purpose of accurate weighing vehicle to aid traffic management systems. The possibility of estimate the velocity, axle and gross weight of a moving vehicle from the surface of pavement tensile strain is investigated. The objective is to develop weigh-in-motion (WIM) technique to estimate the vehicle weight from the pavement responses with fewer disturbances to the vehicle’s vibration and traveling speed, and to provide more reliable and durable WIM systems and sensors. The repeatability, sources of error, and accuracy of weight prediction were discussed.

A new type of capacitive humidity sensor is introduced in this paper. The sensor consists of two plate electrodes coated with MWCNT films and four pieces of isolating medium at the four corners of the sensor. According to capillary condensation, the capacitance signal of the sensor is sensitive to relative humidity (RH), which could be transformed to voltage signal by a capacitance to voltage converter circuit. The sensor is tested using different saturated saline solutions at the ambient temperature of 25 °C, which yielded approximately 11% to 97% RH, respectively. The function of the MWCNT films, the effect of electrode distance, the temperature character and the repeatability of the sensor are discussed in this paper.

Membrane electrode assembly (MEA) is the key component of direct methanol fuel cell (DMFC), the structure and its preparation methods may bring great effects on the cell performances. Due to the requirement of the high performance of the MEA for the micro direct methanol fuel cell (DMFC), we provide a novel double-catalyst layer MEA using CCM-GDE (Catalyst Coated Membrane，CCM；Gas Diffusion Electrode，GDE) fabrication method. The double-catalyst layer is formed with an inner catalyst layer (in anode side: PtRu black as catalyst, in cathode side: Pt black as catalyst) and an outer catalyst layer (in anode side: PtRu/C as catalyst, in cathode side: Pt/C as catalyst). The fabrication procedures are important to the new structured MEA, thus three kinds of fabrication methods are studied, including CCM-GDE, GDE-Membrane and CCM-GDL methods. It was found that the CCM-GDE technology may enhance the contact properties between the catalyst and PEM, and increase the electrode reaction areas, resulted in increasing the performance of the DMFC.

Least square support vector machine (LS-SVM) is widely used in the regression analysis, but the prediction accuracy greatly depends on the parameters selection. In this paper, Simple Genetic Algorithm is applied to optimize the LS-SVM parameters; correspondingly, the prediction accuracy is improved. Sensors are always sensitive to several parameters, and this phenomenon is called cross-sensitivity which restricts the application of sensors in engineering. In order to reduce cross-sensitivity, the model of multi-sensor system measurement is established in this paper. For solving the nonlinear problems in the model, LS-SVM is used to establish the inverse model. It proves that the method has a high forecasting precision. It is beneficial to the application of sensors.