ABSTRACT
With the development of flexible electronic technology, lately, there has been an increase in demand for flexible electronic devices based on soft polymer-substrate metal film structures in challenging applications. These soft polymer-substrate metal film structures must tolerate bending, folding, stretching, and even deformation into any shape without failing to be used successfully. As a result, research into the fracture behavior of soft polymer-substrate metal film structures is essential. The purpose of this study was to investigate how fractures develop in Cr film attached to a polyimide (PI) substrate under biaxial stress. A fracture development model was built to determine the fracture propagation law of soft polymer-substrate metal film structures under biaxial stress. Experiments and finite element methods were applied to verify the correctness of the model. The theoretical analysis and finite element simulation results showed that fractures appeared initially at the perimeter of the film and then propagated to the center under biaxial stress. The theoretical and experimental results indicated that the crack propagation direction was related to the ratio of biaxial loading, which became progressively parallel to the direction of small loading as the biaxial loading ratio increased. The theoretical results were in line with the experiment results, which could be used as a preliminary step for further research on the fracture behavior of film-substrate structures.
ABSTRACT
Schizophrenia is one of the chronic mental disorders characterized by disturbances in thought, emotion, language, perception, and behavior. There is no cure for this disease, and most of the current treatments are palliative. In this study, we aimed to analyze the application of electroencephalographic (EEG) biofeedback therapy, an adjunctive treatment used for many psychiatric disorders, in the rehabilitation of schizophrenic patients. Schizophrenic patients were selected as the experimental subjects, and the initial diagnosis criteria were set accordingly. A primary and a secondary efficacy index was then developed for the evaluation of EEG biofeedback therapy rather than traditional drug treatment. Lastly, the effects of the two methods were compared. The findings indicate that traditional drugs could be used in the treatment of mild schizophrenia, but showed poor results for severe and moderate schizophrenia. EEG biofeedback therapy was effective for the treatment of various degrees of schizophrenia and improved patients' sleep quality and anxiety. These findings have significant practical implications for the rehabilitation of schizophrenic patients and patients with chronic diseases in general.
