The findings of a study on the optimization of Electric Discharge Machining(EDM)procedure for processing cylindrically shaped components with graphite electrodes are presented in this paper.Tool steel 90CrSi was the m...The findings of a study on the optimization of Electric Discharge Machining(EDM)procedure for processing cylindrically shaped components with graphite electrodes are presented in this paper.Tool steel 90CrSi was the material of choice for the study’s workpiece.Additionally,the Electrode Wear Rate(EWR)was chosen as the optimization problem’s objective function.An experiment using the Taguchi design was conducted to address this issue.Additionally,experiments were created and their outcomes were analyzed using the Minitab R19 program.The impact of the input process factors on EWR was investigated,including the powder concentration,the pulse on and off times,the servo current,and the servo voltage.Additionally,the best process variables for a minimal EWR were provided.展开更多
Objective: To study the influence of occupational environment on mental health of nurses. Methods: 671 registered nurses were surveyed with Symptom Checklist 90 (SCL-90).The related factors of positive symptoms were a...Objective: To study the influence of occupational environment on mental health of nurses. Methods: 671 registered nurses were surveyed with Symptom Checklist 90 (SCL-90).The related factors of positive symptoms were analyzed. Results: The nurses showed significantly higher positive item number and scores of somatization and hostility than those of the Chinese female norms. There were significant difference in the score of SCL-90 among the different department nurses; and the nurses who worked in the emergency and obstetric and gynecologic departments had higher score of SCL-90. The analysis of Logistic regression showed that occupational environment had influence on mental health and short nursing experence were related to some positive symptoms. Conclusion: There were some mental problems in the nurse sample and the nurse who worked in different occupational environments had different level of psychological health.展开更多
文摘The findings of a study on the optimization of Electric Discharge Machining(EDM)procedure for processing cylindrically shaped components with graphite electrodes are presented in this paper.Tool steel 90CrSi was the material of choice for the study’s workpiece.Additionally,the Electrode Wear Rate(EWR)was chosen as the optimization problem’s objective function.An experiment using the Taguchi design was conducted to address this issue.Additionally,experiments were created and their outcomes were analyzed using the Minitab R19 program.The impact of the input process factors on EWR was investigated,including the powder concentration,the pulse on and off times,the servo current,and the servo voltage.Additionally,the best process variables for a minimal EWR were provided.
文摘Objective: To study the influence of occupational environment on mental health of nurses. Methods: 671 registered nurses were surveyed with Symptom Checklist 90 (SCL-90).The related factors of positive symptoms were analyzed. Results: The nurses showed significantly higher positive item number and scores of somatization and hostility than those of the Chinese female norms. There were significant difference in the score of SCL-90 among the different department nurses; and the nurses who worked in the emergency and obstetric and gynecologic departments had higher score of SCL-90. The analysis of Logistic regression showed that occupational environment had influence on mental health and short nursing experence were related to some positive symptoms. Conclusion: There were some mental problems in the nurse sample and the nurse who worked in different occupational environments had different level of psychological health.