Mathematical Problems in Engineering

https://www.hindawi.com/journals/mpe/

List of Papers (Total 6,716)

Mixed Fault Detection Filter for Markovian Jump Linear Systems

We tackle the mixed fault detection filter problem for a Markov jump linear system (MJLS) in the discrete-time domain. We present three distinct formulations: the first one is to minimize an upper bound on the subject to a given upper value on the norm; the second one is the opposite situation; that is, we minimize an upper bound on , subject to a given restriction on the norm...

Dynamic Multiaircraft Cooperative Suppression Interference Array Optimization by Dynamic MOPSO Algorithm

Dynamic multiaircraft cooperative suppression interference array (MACSIA) optimization problem is a typical dynamic multiobjective optimization problem. In this paper, the sum of the distance between each jamming aircraft and the enemy air defense radar network center and the minimum width of the safety area for route planning are taken as the objective functions. The dynamic...

A New Error Prediction Method for Machining Process Based on a Combined Model

Machining process is characterized by randomness, nonlinearity, and uncertainty, leading to the dynamic changes of machine tool machining errors. In this paper, a novel model combining the data processing merits of metabolic grey model (MGM) with that of nonlinear autoregressive (NAR) neural network is proposed for machining error prediction. The advantages and disadvantages of...

Modal Analysis of a New Thermosensitive Actuator Design for Circuit Breakers Based on Mesoscale U-Shaped Compliant Mechanisms

A new mesoscale thermosensitive actuator design for circuit breakers based on a U-shaped compliant mechanism was introduced as a potential replacement for bimetal strips in miniature circuit breakers. In a previous study, the response of this design to the thermal fields produced by a steady current flow was analyzed. This article presents a modal analysis of the compliant...

Kinematic Calibration Based on the Multicollinearity Diagnosis of a 6-DOF Polishing Hybrid Robot Using a Laser Tracker

A general methodology for ensuring the geometric accuracy of a 6-DOF polishing hybrid robot having a 3UPS and UP parallel mechanism and a 3-DOF wrist is presented. The process is implemented in three steps: formulation of the error model containing complete source errors such as offset errors of the actuated joints and structural errors of the joints and links utilizing product...

Research on High-Precision Form Grinding Technology of Gear Based on Ambient Temperature Adaptability

The thermal error of high-precision computer numerical control (CNC) form grinding machine has become the critical factor affecting its locating precision. Because the thermal error is more complicated to be measured directly, most of the measurement tests are usually aimed at no-load conditions. In this article, a method to evaluate the machine tool thermal error based on the...

A Novel Kinematic Parameters Identification Method for Articulated Arm Coordinate Measuring Machines Using Repeatability and Scaling Factor

Kinematic parameters identification and compensation are effective ways to improve the accuracy of articulated arm coordinate measuring machines (AACMMs) and robotic arms without increasing the cost of hardware. Generally, kinematic parameters identification methods based on standard references are relatively high in accuracy but time-consuming and not suitable for industrial...

Text Case-Based Reasoning Framework for Fault Diagnosis and Predication by Cloud Computing

In Discrete Event System, such as railway onboard system, overwhelming volume of textual data is recorded in the form of repair verbatim collected during the fault diagnosis process. Efficient text mining of such maintenance data plays an important role in discovering the best-practice repair knowledge from millions of repair verbatims, which help to conduct accurate fault...

Joint and Control Charts Optimal Design Using Genetic Algorithm

A simple and flexible model for economic statistical design of joint and control charts was proposed. The design problem was approached by constrained fuzzy multiobjective modeling for three objectives: joint power, joint Type I error, and joint total control cost. Fuzzy membership functions were created to measure the satisfaction levels of the objectives, and the overall...

Numerical Investigation of Particle Concentration Distribution Characteristics in Twin-Tunnel Complementary Ventilation System

Longitudinal ventilation systems are commonly installed in new tunnels. In this paper, based on the similarity law, the scale model with a view to different conditions is carried out to study the effectiveness of twin-tunnel complementary ventilation system. The system can offer enough amount of fresh air to meet requirement of driving safety by using longitudinal ventilation...

A Tidal Level Prediction Approach Based on BP Neural Network and Cubic B-Spline Curve with Knot Insertion Algorithm

Tide levels depend on both long-term astronomical effects that are mainly affected by moon and sun and short-term meteorological effects generated by severe weather conditions like storm surge. Storm surge caused by typhoons will impose serious security risks and threats on the coastal residents’ safety in production, property, and life. Due to the challenges of nonperiodic and...

A Community Related Influence Evaluation Model for Social Networks with a Dynamic Perspective

The nature of free information diffusion and sharing in social networks (SNs) has increasingly attracted users to gather in communities to facilitate communication, resulting in increased challenges to community influence analysis in SNs. In SNs, the ability to evaluate how a community affects other users and communities is essential for further applications. Although...

New Insights into Approaches to Evaluating Intention and Path for Network Multistep Attacks

The attack graph (AG) is an abstraction technique that reveals the ways an attacker can use to leverage vulnerabilities in a given network to violate security policies. The analyses developed to extract security-relevant properties are referred to as AG-based security evaluations. In recent years, many evaluation approaches have been explored. However, they are generally limited...

Second-Order Sliding Mode Disturbance Observer-Based Adaptive Fuzzy Tracking Control for Near-Space Vehicles with Prescribed Tracking Performance

An adaptive fuzzy fault-tolerant tracking controller is developed for Near-Space Vehicles (NSVs) suffering from quickly varying uncertainties and actuator faults. For the purpose of estimating and compensating the mismatched external disturbances and modeling errors, a second-order sliding mode disturbance observer (SOSMDO) is constructed. By introducing the norm estimation...

Study on the Deformation and Stress Analysis of the Sponge/Rubber Adapter

The analysis of adaptors’ deformation and stress is an important prerequisite for the design of the adapters. This paper proposed the mathematical description and analytical method for the sponge cylinder and rubber cylinder under pressure. The analytical formulas on deformation and stress of interference fit between adapters and launchers are deduced. Also, the correctness of...

Global Dynamics of a Virus-Immune System with Virus-Guided Therapy and Saturation Growth of Virus

We considered a piecewise virus-immune dynamic model to investigate the effectiveness of the HIV virus loads-guided structured treatment interruptions (STIs). To better describe the biological reality, we extended the existing models by taking the carrying capacity of the virus loads into consideration to indicate the saturated growth of virus loads. We initially investigated the...

Two-Stage Fuzzy Logic Model for Cloud Service Supplier Selection and Evaluation

Dynamicity of the cloud computing system, complexity of real-world decision-making problems, and nontransparent market imply numerous difficulties in finding the corresponding solution for cloud supplier evaluation and selection. Due to that reason, there is a need to develop a model that can contribute to increase of reliability of evaluation and reduction of subjectivity of the...

Semianalytical Solutions of Relative Motions with Applications to Periodic Orbits about a Nominal Circular Orbit

In the dynamical model of relative motion with circular reference orbit, the equilibrium points are distributed on the circle where the leader spacecraft is located. In this work, analytical solutions of periodic configurations around an arbitrary equilibrium point are constructed by taking Lindstedt-Poincaré (L-P) and polynomial expansion methods. Based on L-P approach, periodic...

Stochastic Optimal Control of Investment and Dividend Payment Model under Debt Control with Time-Inconsistency

This paper considers the optimal debt ratio, investment, and dividend payment policies for insurers with time-inconsistency. The surplus process of an insurance company is determined by the change of asset value and the change of liabilities. The asset can be invested in financial market which contains a risky asset and a risk-free asset, and when the insurer incurs a liability...

An Entropy-Histogram Approach for Image Similarity and Face Recognition

Image similarity and image recognition are modern and rapidly growing technologies because of their wide use in the field of digital image processing. It is possible to recognize the face image of a specific person by finding the similarity between the images of the same person face and this is what we will address in detail in this paper. In this paper, we designed two new...

Strong Solutions and Global Attractors for Kirchhoff Type Equation

We study the long-time behavior of the Kirchhoff type equation with linear damping. We prove the existence of strong solution and the semigroup associated with the solution possesses a global attractor in the higher phase space.

Dual-Layer Optimal Dispatching Strategy for Microgrid Energy Management Systems considering Demand Response

The continuous development of microgrid’s technology creates favorable conditions for the access of distributed energy. Firstly, in order to consider the interests of the demand side and the power side, this paper presents a dual-layer optimal dispatching model of microgrid based on demand response. The objective of the first-layer optimization is to obtain the maximum load...

A New Synchronization Technique of a Three-Phase Grid Tied Inverter for Photovoltaic Applications

Three-phase grid synchronization is one of the main techniques of the three-phase grid connected power inverters used in photovoltaic systems. This technique was used to reach the fast and accurate three-phase grid tied inverter synchronization. In this paper a new synchronization method is presented on the basis of integrating the grid voltage two times (line-to-line or phase...