Papers by Keyword: Complexity

Abstract: Human lower limbs are the most important parts of human body due to their supporting the whole body in the process of human motions. There are many pathological joint diseases and accidental damage, such as traffic accident and falling off from high place, influencing the human daily life seriously. Therefore, dynamic model of human lower limb has received considerable interest from multi-disciplines including flexible mechanisms, smart structures, biomechanics and nonlinear dynamics. This paper establishes the simplified simulation model of human lower limb based on the acquired realistic data from human motions under different speeds. The model can not only describe dynamic characteristics of real lower limb but also can be simulated by realistic human lower limb motion excitation acquired by tri-axial accelerometers and inclinometers in different conditions. Consequently, the detailed dynamic information of human lower limb from the proposed model can be obtained. In order to analyze the variability of human motions, multiscale entropy (MSE) is employed to investigate the complexity of human motion signals for different speeds of motion. Motion transition characteristics under different speeds are exhibited for understanding adaptation mechanism of human motion. The results will be helpful for exoskeleton and lower limb rehabilitation robot.

Abstract: Lithium-ion batteries are a key technology for energy storage not only in consumer electronics but also in e-mobility and stationary applications. However, in order to guarantee the success of lithium-ion batteries in the long term, improvements related to performance, lifetime and production costs need to be made. Mastery of the highly interlinked process chain in lithium-ion battery manufacturing is a challenge and often acquired on the basis of experience. This paper illustrates the complexity of this process chain with a special focus on the roll-to-roll manufacturing of electrodes and discusses the application of a quality management system in lithium-ion battery production.

Abstract: The use of industrial grippers induces to deal with the system grippers are embedded in. Besides the gripper this includes the environment, the handling device the gripper is attached to, the task the gripper should perform and the part to be handled. All this domains form the system handling. The paper analyses this system using different methods of the field of structural complexity management. Objective is to identify the most important and most influential factors governing the system.

Abstract: This paper proposes a conceptual framework in determining manufacturing complexity. Manufacturing complexity is divided into five main components which are product behaviour, infrastructure capability, production planning, information management and personnel perception. These five main components then divided into twelve sub components. Lastly all these components are classified in two categories which are internal complexity and external complexity. These components are interrelated, such that a bi-directional relationship exists between internal and external complexity. The conceptual framework initiated in this paper can be used by manufacturers to gain more understanding on manufacturing complexity. Thus manufacturers can take proper actions to align themselves with the issues brought forth by manufacturing complexity.

Abstract: For current problem of the urgent needs for moving targets’ estimated trajectory and the large algorithm complexity for trajectory estimation algorithm, without affecting the accuracy requirements of the track, put forward an algorithm of target trajectory estimation based on energy attenuation of wireless sensor nodes (ETT-EA). The algorithm is a high degree of concern from the current direction of node energy attenuation, which roughly calculates the trajectory of invasion target. Simulation results show that the algorithm saves the complexity of the algorithm with satisfying certain trajectory estimation accuracy, which is simple and adapted to specific environments.

Abstract: The effective resource allocation in production system is the key to high performance. This paper firstly analyses the entropy increase which damages the factors’ operation, then the information entropy theory is extended to establish a complexity model based on size, difficulty, and state diversity. On the basis of complexity, the decline of factors’ utilization efficiency is described. Moreover, some specific management methods are introduced to illustrate the importance of complexity control.

Abstract: This paper proposes an improved amplitude spectrum based Fourier-Mellin algorithm Fourier by studying the nature of the Fourier transform image of the amplitude spectrum and the application of phase spectrum in estimation for image motion vector according to the shortcomings of traditional Fourier-Mellin algorithm when the video image translation, rotation and scaling of the situation exist. Experimental results show that the algorithm can estimate the rotation, translation and other vector parameters of a complicated motion model .The complexity of the algorithm has greatly improved comparing to the traditional Fourier-Mellin algorithm.

Abstract: Production scheduling and control under uncertainty is among the most persistent challenges in the field of operation management. Despite the significant amount of research in this domain, many studies still underline the gap between scheduling theory and practice. In this paper, we outline the important aspects to consider in the design and implementation of decision support systems for the scheduling task by reviewing the literature. From the identified guidelines, we examine a practical case and propose a decision support system for the production scheduling task in an actual manufacturing environment.

Abstract: Weight function neural network is a new kind of neural network developed in recent years, which has many advantages, such as finding globe minima directly, good performance of generalization, extracting some useful information inherent in the problems and so on. Time complexity is an important measure of algorithm. This paper studies the complexity of neural network using second class orthogonal weight functions. The results indicate that the neural network has a linear relationship with the dimensions of input layer and output layer, an O (n³) relationship with the number of samples. Finally gives some simulation experiments for time complexity.

Abstract: To improve the objectivity and accuracy of evaluation for electromagnetic environment complexity and its influence on communication equipment, a subjective complexity evaluation method of electromagnetic environment oriented to the communication equipment is presented based on sensitivity and RF protection ratio of communication equipment. Based on statistical concept, the energy correlation factor is modified, and modulation and polarization correlation concept are imported into this method, by which the factor of energy correlation is modified and the subjective evaluation is made by analyzing the time domain correlation, frequency domain correlation, energy domain correlation, modulation correlation and polarization correlation of the electromagnetic environment. These simulation results indicate that communication equipment with various working parameters are influenced differently under the same electromagnetic environment. Namely, the complexities of electromagnetic environment for communication equipment with various working parameters are different.