Finite element analysis of high field permanent magnet mechanism using vector Preisach hysteresis model
This paper presents a method to simulate abnormal magnetizations in high field permanent magnet mechanism. Abnormal magnetizations including local saturation, local demagnetization and rotational magnetization occur in the assembly process of high field permanent magnet mechanism. Combining an anisotropic vector Preisach model and finite element analysis, abnormal magnetizations are simulated comprehensively. The method only requires the data of limiting magnetic hysteresis loops of the material along easy and hard axis, so the application of vector Preisach model becomes convenient and efficient. A sixteen elements enhanced magic ring is designed and the process of assembling is simulated, which verify the validity of the presented method.
Finite Element Analysis of Permanent Magnet Assembly With High Field Strength Using Preisach Theory
This paper presents a method to simulate the characteristics of permanent magnet materials with a magnetic field varying arbitrarily. Combining Preisach model and finite element analysis, a dynamic magnetic field computation is implemented for a permanent magnet assembly in a process of assembling. The hysteresis characteristic including local loop and rotational magnetization are considered in the formulation of the method proposed. The numerical results are compared with the ones of a conventional method, the electric current sheet equivalent, and the measured values to verify the validity of the presented method
Inference and Evidence in Archaeology: A Discussion of the Conceptual Problems
Publisher Summary This chapter dicsusses the general features of scientific inference and explains the way inference has been discussed by archaeologists. It presents an explication of current problems in the various areas: (1) the justification of archaeological conclusions, (2) the concepts of archaeological evidence, and (3) the undeveloped relations between archaeological theory and archaeological evidence. The chapter defines these problems and explains the way to resolve them. To resolve many of the problems surrounding uncertain links between inference and evidence, archaeologists should develop a rigorous model that specifies the way information about the past is transmitted to the present via material remains. The chapter presents the structure of such a model. However, establishing relevant data to support conclusions about past phenomena is only part of the overall process of generating archaeological knowledge. Some of the processes responsible for producing the material remains that archaeologists manipulate in assembling evidence to support claims about past phenomena are described in the chapter.