The accurate air-fuel ratio (AFR) control is crucial for the exhaust emission reduction based on the three-way catalytic converter in the spark ignition (SI) engine. The difficulties in transient cylinder air mass flow measurement, the existing fuel mass wall-wetting phenomenon, and the unfixed AFR path dynamic variations make the design of the AFR controller a challenging task. In this paper, an adaptive AFR regulation controller is designed using the feedforward and feedback control scheme based on the dynamical modelling of the AFR path. The generalized predictive control method is proposed to solve the problems of inherent nonlinearities, time delays, parameter variations, and uncertainties in the AFR closed loop. The simulation analysis is investigated for the effectiveness of noise suppression, online prediction, and self-correction on the SI engine system. Moreover, the experimental verification shows an acceptable performance of the designed controller and the potential usage of the generalized predictive control in AFR regulation application.

Fringe projection systems have been widely applied in three-dimensional (3D) shape measurements. One of the important issues is how to retrieve the absolute phase. This paper presents a modified gray-level coding method for absolute phase retrieval. Specifically, two groups of fringe patterns are projected onto the measured objects, including three phase-shift patterns for the wrapped phase, and three n-ary gray-level (nGL) patterns for the fringe order. Compared with the binary gray-level (bGL) method which just uses two intensity values, the nGL method can generate many more unique codewords with multiple intensity values. With assistance from the average intensity and modulation of phase-shift patterns, the intensities of nGL patterns are normalized to deal with ambient light and surface contrast. To reduce the codeword detection errors caused by camera/projector defocus, nGL patterns are designed as n-ary gray-code (nGC) patterns to ensure that at most, one code changes at each point. Experiments verify the robustness and effectiveness of the proposed method to measure isolated objects with complex surfaces.

Air-fuel ratio (AFR) control is important for the exhaust emission reduction while using the three-way catalytic converter in the spark ignition (SI) engine. However, the transient cylinder air mass is unable to acquire by sensors directly and it may limit the accuracy of AFR control. The complex engine dynamics and working conditions make the intake air estimation a challenge work. In this paper, a novelty design of intake air observer is investigated for the port-injected SI engine. The intake air dynamical modeling and the parameter fitting have been carried out in detail. Extended Kalman Filter (EKF) has been used to optimize the instantaneous cylinder charge estimation and minimize the effort of pump gas fluctuation, random noise, and measurement noise. The experiment validation has been conducted to verify the effectiveness of the proposed method.

In the Internet of Vehicles (IoV), the data sharing between the participating vehicles and the roadside units (RSUs) provides intelligent ground transportation with convenience and connectivity. To date, IoV has produced massive heterogeneous traffic data, needing to consume petabytes of computing and spectrum resources. However, due to limited computing resources, vehicles have to offload some tasks to RSUs, raising the issue of resource allocation efficiency in the IoV. This paper focuses on two aspects: the optimization of the resource allocation efficiency on the data processing and transmission, and the security of cloud-based services. Though blockchain technology provides a feasible solution for the safe interaction of IoV information, the consensus process of blockchains still involves much resource consumption. To address the issue, this paper proposes a Blockchain-Based and Resource Allocation Balanced Information Interaction Mechanism (BRAB-IIM) to achieve a balance between efficiency and security. In BRAB-IIM, maximizing the overall interests of the resource trading market and minimizing resource consumption are the two conflicting goals. Meanwhile, a vehicle classification method is proposed, which considers the real-time urgency of interactive information. Additionally, a Hierarchical Delegated Proof of Reputation (hDPoR) consensus mechanism is designed, which combines the reputation value of the vehicle and the priority level of the node vote through prioritizing vehicle demands. Finally, three different optimization algorithms are deployed for the dual-objective optimization of the overall market resource allocation. The experimental results indicate that, compared to the baseline algorithm, the NSGA-II algorithm increases the overall market revenue by 24% under the same energy consumption. Also, it is numerically validated that the BRAB-IIM improves the effectiveness and security of the IoV.

Fringe projection technologies have been widely used for three-dimensional (3D) shape measurement. One of the critical issues is absolute phase recovery, especially for measuring multiple isolated objects. This paper proposes a method for absolute phase retrieval using only one coded pattern. A total of four patterns including one coded pattern and three phase-shift patterns are projected, captured, and processed. The wrapped phase, as well as average intensity and intensity modulation, are calculated from three phase-shift patterns. A code word encrypted into the coded pattern can be calculated using the average intensity and intensity modulation. Based on geometric constraints of fringe projection system, the minimum fringe order map can be created, upon which the fringe order can be calculated from the code word. Compared with the conventional method, the measurement depth range is significantly improved. Finally, the wrapped phase can be unwrapped for absolute phase map. Since only four patterns are required, the proposed method is suitable for real-time measurement. Simulations and experiments have been conducted, and their results have verified the proposed method.