A quantitative assessment method is proposed to sense the specific effects of atmospheric icing conditions on flight safety. A six degree-of-freedom computational flight dynamics model is used to study the effects of ...A quantitative assessment method is proposed to sense the specific effects of atmospheric icing conditions on flight safety. A six degree-of-freedom computational flight dynamics model is used to study the effects of ice accretion on aircraft dynamics, and a pilot model is also involved. In order to investigate icing severity under different icing conditions, support vector regression is applied in establishing relationship between aircraft icing parameter and weather conditions. Considering the characteristics of aircraft icing accidents, a risk probability assessment model optimized by the particle swarm method is developed to measure the safety level. In particular, angle of attack is chosen as a critical parameter in this method. Results presented in the paper for a series of simulation show that this method captures the basic effects of atmospheric icing conditions on flight safety, which may provide an important theoretical reference for icing accidents avoidance.展开更多
Objective To assess the risk factors for upper extremity-work-related musculoskeletal disorders（UE-WMSD） on 13 prod ucti on lines in an airbag factory using the threshold limit values-American conference of industri...Objective To assess the risk factors for upper extremity-work-related musculoskeletal disorders（UE-WMSD） on 13 prod ucti on lines in an airbag factory using the threshold limit values-American conference of industrial hygienists-hand activity level（TLV-ACGIH-HAL） method and introduce the ergonomic improvement to reduce the repe titi veness and the peak force（Pf）.Methods Professional exposure level on 13 production lines in a automobile factory was measured using the TLV-ACGIH-HAL method and a further risk was assessed according to the ergonomic improvement.Results The first assessment of 9 produc tion lines showed that the professional exposure level was above the TLV or HAL limit.The second assessment showed that the professional exposure level was below the AL limit on all production lines except 1,in which the professional exposure level was between TLV and HAL.Conclusion The assessment of UE-WMSD-related risk can ide ntif y the riskiest emplacements and evaluate the reduc tion of risk in professional exposure through interventi ons of structuralorganizati onal type.展开更多
文摘A quantitative assessment method is proposed to sense the specific effects of atmospheric icing conditions on flight safety. A six degree-of-freedom computational flight dynamics model is used to study the effects of ice accretion on aircraft dynamics, and a pilot model is also involved. In order to investigate icing severity under different icing conditions, support vector regression is applied in establishing relationship between aircraft icing parameter and weather conditions. Considering the characteristics of aircraft icing accidents, a risk probability assessment model optimized by the particle swarm method is developed to measure the safety level. In particular, angle of attack is chosen as a critical parameter in this method. Results presented in the paper for a series of simulation show that this method captures the basic effects of atmospheric icing conditions on flight safety, which may provide an important theoretical reference for icing accidents avoidance.
文摘Objective To assess the risk factors for upper extremity-work-related musculoskeletal disorders（UE-WMSD） on 13 prod ucti on lines in an airbag factory using the threshold limit values-American conference of industrial hygienists-hand activity level（TLV-ACGIH-HAL） method and introduce the ergonomic improvement to reduce the repe titi veness and the peak force（Pf）.Methods Professional exposure level on 13 production lines in a automobile factory was measured using the TLV-ACGIH-HAL method and a further risk was assessed according to the ergonomic improvement.Results The first assessment of 9 produc tion lines showed that the professional exposure level was above the TLV or HAL limit.The second assessment showed that the professional exposure level was below the AL limit on all production lines except 1,in which the professional exposure level was between TLV and HAL.Conclusion The assessment of UE-WMSD-related risk can ide ntif y the riskiest emplacements and evaluate the reduc tion of risk in professional exposure through interventi ons of structuralorganizati onal type.
