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The decompression operations of the fractured optic nervecanal by the transethmosphenoidal approach on 11 blind cases were perfor-med. The visual acuity improved in 8 cases (72%) out of 11 cases. It wasnoted that the earlier the surgery, the better the prognosis. The operativeprocedures were introduced and the failure factors were analyzed. 作者采用鼻外经筛蝶窦进路的视神经管减压术治疗因外伤性视神经管骨折导致失明的病人11例。其中8例病人获得不同程度的视力恢复,总有效率72%。本文介绍了手术方法,分析了手术成败的原因,得出了手术时间越早视力恢复越好的结论。 The paper describes modeling of early failure model of power GaAs MESFET with its ageing test,environmental and life tests. The degree of reliability is briefly estimated.The main failure factors are pointed on as well. And catastrophic failure burn is discussed with experimental method in detail.Failure factors are also analysed. The emphasis is laid on a possible method which can improve the reliability. 本文通过功率GaAs MESFET的筛选与环境、寿命试验阐述了器件的早期失效模式模型,估计了可靠性水平,指出了主要失效因素,并用实验方法讨论了突变烧毁失效,分析了失效原因,探讨了提高可靠性的途径。 In this paper, a total criterion on elastic and fatigue failure in complex stress, that is, octahedral stress strength theory on dynamic and static states, is proposed on the basis of studying modern and classic strength theories. At the same time, an analysis of an independent and fairly comprehensive theoretical system is set up. It gives generalized failure factor by 36 materials and computative theory of the 11 states of complex stresses on a point, and derives the operator equation on generalized... In this paper, a total criterion on elastic and fatigue failure in complex stress, that is, octahedral stress strength theory on dynamic and static states, is proposed on the basis of studying modern and classic strength theories. At the same time, an analysis of an independent and fairly comprehensive theoretical system is set up. It gives generalized failure factor by 36 materials and computative theory of the 11 states of complex stresses on a point, and derives the operator equation on generalized allowable strength and a computative method for a total equation can be applied to dynamic and static states. It is illustrated that the method has a good exactness through computation of eight examples of engineering. Therefore, the author suggests applying it to engineering widely. 本文,在研究现代和经典强度理论的基础之上,提出了一个在复杂应力下弹性失效与疲劳失效的总准则,即动态静态八面体应力强度理论,同时建立了并分析了一个独立的比较完整的理论体系,给出了36种材料广义失效系数,和一点复杂应力的11个状态的计算理论,导出了广义允许强度算子方程.给出了总准则能应用到静态、动态的计算方法,通过8个工程实例的计算,表明该方法有很高的精度,因而笔者建议广泛地应用到工程.
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