Analysis of the One Dimensional Steady State Semiconductor Multijunction Device Model with the Avalanche Effect *

In this paper we consider the stationary multijunction device model with the avalanche effect. Using the singular perturbation method, an approximation to the current voltage curve is obtained. The cause and the condition for the occurrence of saturation current is analyzed. Especially, it is pointed that the avalanche effect is responsible for the blowing up of the saturation current. We prove the existence of multiple steady state solution when the ionization rate is relatively small. Finally, some numerical examples are presented to show the reliability of the theoretical results.

因地制宜 因情治矿——阜新局对报废矿井放开经营的成功尝试

任何事物都有其发生、发展和衰老的过程,煤矿尤其是这样。对于每个矿务局来说,随着开采时间的推移,陆续有一些矿井报废,而这些衰老报废矿井普遍存在产量低、成本高、亏损大、效益差的严重问题,如何解决这些问题,是摆在煤炭企业各级领导干部面前的一个重要课题。 事实证明,阜新矿务局对衰老报废矿井实行放开经营,是解决上述问题较好的办法。

开创一片新天地——阜新局困境中发展多元化经营构想

阜新矿务局多种经营企业始创于1975年。到目前已发展成为拥有61个厂矿二级公司,独立核算企业755个,职工90731人,横跨煤炭、建筑、安装、运输、商饮、轻纺、化工等行业的综合经济联合体。 尽管从总体上看,该局多种经营有了长足的进步,但同其它衰老矿区一样,发展缓慢、经营困难的现象仍严重存在。主要表现在: