Bin Xu

From the perspective of sensorless control for PMSM, this book analyzes and integrates the two control methods of high-speed and zero-low-speed ranges, to achieve full-speed control. A composite control based on weighted switching method is established, which effectively combines the good dynamic tracking performance of the model reference adaptive control method in the high-speed range and the high-precision control of the pulse injection method in the zero-low-speed range. The intermediate speed range where the two methods transition is controlled by the weighted method. Multiple control strategies are integrated and weighted according to the characteristics of PMSM operation at different speed ranges, ultimately overcoming the limitation of a single sensorless control method not being suitable for the full speed range. The PI structure of the speed adaptive law in the traditional model reference adaptive system will lead to the problems of reduced speed identification accuracy and poor robustness, the super-twisting sliding mode algorithm in the high-order sliding mode algorithm is proposed to improve the PI structure of the speed adaptive law in the traditional model.

This updated fascicle is your essential guide to thyroid and parathyroid tumors, reflecting a decade of significant advancements. It adopts the 5th edition of the WHO classification, offering detailed histologic findings with a strong emphasis on differential diagnosis. You'll find comprehensive explanations of molecular pathology and genetic alterations, with sections on molecular profiles in each chapter dedicated to a histologic thyroid or parathyroid entity to aid diagnosis. The thyroid cytology chapter has been extensively remodeled and expanded given the importance of preoperative diagnosis in the management of thyroid nodules and now follows the current Bethesda System for Reporting Thyroid Cytopathology. Plus, all chapters include the latest on prognosis and therapy, based on guidelines from the American Thyroid Association and National Comprehensive Cancer Network. Designed to empower pathologists and other physicians, this fascicle helps you better understand, diagnose, predict the behavior of, and guide the management of patients afflicted with tumors and related lesions of these organs.

This open access book provides a complete probabilistic analysis method and a performance-based seismic safety evaluation for high concrete faced rockfill dam (CFRD). Combined with random sample generation and reliability analysis methods, the dynamic response characteristics and reliability level of CFRD under various random factors are comprehensively described. In Chapter 2, a random ground motion model based on spectral representation-random function and a high-dimensional random variable generation method based on GF- discrepancy are established. Combined with probability density evolution method (PDEM) and the random sample generation methods to verify its effectiveness and reliability for nonlinear complex geotechnical engineering. In Chapter 3, the dynamic response and probabilistic characteristics of high CFRD under random ground motion are revealed based on the elastoplastic analysis. A performance-based seismic safety evaluation method is established. In Chapter 4, the influence of material parameter randomness on dynamic response and seismic safety of high CFRD is studied from the perspective of stochastic dynamics and probability. In Chapter 5, the stochastic dynamic response and probability distribution of high CFRD under the coupled random action of ground motion and material parameters are systematically studied, and the performance-based seismic safety evaluation framework is improved. In Chapter 6, The stochastic dynamic response of 3D high CFRD is studied, and the failure performance index and performance level based on overstress volume ratio combined with overstress accumulation time are discussed. The performance-based seismic safety evaluation framework is further improved. In Chapter 7, combined with the finite element dynamic time-history analysis method considering the softening effect of rockfill, a performance-based seismic safety evaluation framework for dam slope stability of high CFRD under multiple random factors is systematically explored from the perspective of stochastic dynamics and probability. In Chapter 8, The performance indexes of seismic safety evaluation for high CFRDs are suggested and the corresponding performance level with probability assurance is put forward. The multi-seismic intensity - multi-performance target - failure probability performance relationship is established, and a performance-based seismic safety evaluation framework is initially formed. This book can be used as a reference for scholars studying random vibration and reliability analysis, as well as for scholars studying dam safety evaluation.

The 2008 Sichuan earthquake killed 87,000 people and left 5 million homeless. In response to the devastation, an unprecedented wave of volunteers and civic associations streamed into Sichuan to offer help. The Politics of Compassion examines how civically engaged citizens acted on the ground, how they understood the meaning of their actions, and how the political climate shaped their actions and understandings. Using extensive data from interviews, observations, and textual materials, Bin Xu shows that the large-scale civic engagement was not just a natural outpouring of compassion, but also a complex social process, both enabled and constrained by the authoritarian political context. While volunteers expressed their sympathy toward the affected people's suffering, many avoided explicitly talking about the causes of the suffering—particularly in the case of the collapse of thousands of schools. Xu shows that this silence and apathy is explained by a general inability to discuss politically sensitive issues while living in a repressive state. This book is a powerful account of how the widespread death and suffering caused by the earthquake illuminates the moral-political dilemma faced by Chinese citizens and provides a window into the world of civic engagement in contemporary China.