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As the core component of electronic equipment, vibration load has an important effect on the reliability of circuit boards. However, construction machinery has high requirements for construction efficiency and safety performance, and also has high maintenance costs. In this paper, a vibration reliability analysis and structural optimization of the control circuit board of a drilling rig are conducted. First, Failure Mode, Effects and Criticality Analysis (FMECA) and Fault Tree Analysis (FTA) qualitative and quantitative analysis were used to find the weak links in the circuit board. The quantitative and qualitative analysis results of FMECA and FTA show that the critical probability importance values of the chip inductor and TVS diode short circuit are the highest, at 0.249 and 0.173, respectively. They are up to 0.239 higher than those of the other components. Then, according to the analysis results, a precise simplified model is established for the core components, including the weak links, and modal simulations and modal tests are carried out. The key influencing parameters are obtained through comparative analysis and research on natural frequency and frequency response curves. Finally, the position of the stress–strain sensitive source in the real working environment is determined by a dynamic simulation analysis of the random vibration performance of the finite element model. The results can provide an optimization basis for an anti-vibration design of circuit boards. [ABSTRACT FROM AUTHOR]

Purpose: According to the lung cancer staging project, T1a (≤ 2 cm) non-small-cell lung cancer (NSCLC) should be additionally classified into ≤ 1 cm and > 1 to 2 cm groups. This study aimed to investigate the surgical procedure for NSCLC ≤ 1 cm and > 1 to 2 cm., Methods: We identified 15,760 patients with T1aN0M0 NSCLC after surgery from the Surveillance, Epidemiology, and End Results database. Overall survival (OS) and lung cancer-specific survival (LCSS) were compared among patients after lobectomy, segmentectomy, or wedge resection. The proportional hazards model was applied to evaluate multiple prognostic factors., Results: OS and LCSS favored lobectomy compared with segmentectomy or wedge resection in patients with NSCLC ≤ 1 cm and > 1 to 2 cm. Multivariable analysis showed that segmentectomy and wedge resection were independently associated with poorer OS and LCSS than lobectomy for NSCLC ≤ 1 cm and > 1 to 2 cm. With sublobar resection, lower OS and LCSS emerged for NSCLC > 1 to 2 cm after wedge resection, whereas similar survivals were observed for NSCLC ≤ 1 cm. Multivariable analyses showed that wedge resection is an independent risk factor of survival for NSCLC > 1 to 2 cm but not for NSCLC ≤ 1 cm., Conclusion: Lobectomy showed better survival than sublobar resection for patients with NSCLC ≤ 1 cm and > 1 to 2 cm. For patients in whom lobectomy is unsuitable, segmentectomy should be recommended for NSCLC > 1 to 2 cm, whereas surgeons could rely on surgical skills and the patient profile to decide between segmentectomy and wedge resection for NSCLC ≤ 1 cm., (© 2016 by American Society of Clinical Oncology.)