三极管集——基短路后的工作特性分析

从三极管的内部结构、物理特性以及三极管的输出特性分析了三极管集——基短路后的工作特性，从而得出结论：在镜像电流源中，三极管集——基短路后还会有Lc，而且Lc≈βIB。     

A Second Order Training Algorithm for Multilayer Feedforward Neural Networks

ＡＳｅｃｏｎｄＯｒｄｅｒＴｒａｉｎｉｎｇＡｌｇｏｒｉｔｈｍｆｏｒＭｕｌｔｉｌａｙｅｒＦｅｅｄｆｏｒｗａｒｄＮｅｕｒａｌＮｅｔｗｏｒｋｓＴａｎＹｉｎｇ（谭营）ＨｅＺｈｅｎｙａ（何振亚）（ＤｅｐａｒｔｍｅｎｔｏｆＲａｄｉｏＥｎｇｉｎｅｅｒｉｎｇ，Ｓｏｕ...     

试论《行政许可法》颁布后的治安管理

《行政许可法》颁布后，公安机关的治安管理职能发生较大的转变，前置审批权削弱，临场检查任务量加大。公安机关的治安管理部门应通过工作重心从事前审批到事中监督和事后查处上的转移，改革传统的只管不查模式，提高治安管理工作效率。     

邓小平国际新秩序和老布什世界新秩序构想的比较

冷战结束后 ,雅尔塔格局彻底崩溃 ,面对急剧变化的国际形势 ,邓小平和乔治·布什分别提出了建立国际政治经济新秩序的构想 ,两种不同构想对两国的外交政策和战略调整以及当今国际形势的发展起了重要的影响作用     

代数偏微分方程组的对合特征集方法分析（英文）

基于Wu-Ritt特征集方法和V.Gerdt的对合除法, 我们定义了非线性偏微分方程组的关于一般延拓方向的对合特征集 (ICS). 影响ICS方法的两个主要因素为: 延拓方向和变量的序. 本文中, 应用ICS方法处理在计算偏微分方程组的对称群过程中产生的大型偏微分方程组. 在实验的基础上, 总结了对于ICS方法较好的延拓方向和变量的序.     

饱和土体中半封闭压力隧洞的应力和位移场

基于Biot固结理论，研究分析了饱和土体中半封闭压力隧洞问题，建立了压力隧洞的半封闭边界条件．通过对控制方程的解耦，得到了孔隙水压力的消散方程．在Laplace变换域中得到隧洞边界上作用轴对称荷载和流体压力条件下的应力、位移和孔隙水压力解答，考虑了土体和孔隙流体的压缩性，运用Laplace数值逆变换得到时域中的解．文末给出了算例，分析了隧洞的半封闭特性对应力、位移和孔隙水压力的影响。     

科研管理中瓶颈问题分析

瓶颈问题可通过改变颈口面积和颈口秩序来解决。本文首先建立了颈口面积模型和颈口秩序模型，并用案例说明了其运用方法。该瓶颈模型还可用在经济分析、生产管理等许多问题的分析上。     

《新世训》何以为“训”

针对冯友兰先生在抗日战争时期以生活方法新论为副标题的《新世训》何以为“训”来展开论述,其一它是“接着讲”而并非“照着讲”;其二它是“周全之道”而并非“偏至之端”。     

隔爆对旋式局部通风机控制磁力起动器的研究

煤矿井下局部通风机是保证煤矿井下安全生产的重要设备.对旋局部通风机是一种用途广泛的新型局部通风机,具有结构紧凑、噪音小、效率高、反风性能好的特点.研制与其配套的起动和控制设备是十分必要的.     

Comparison of high order aberration after conventional and customized ablation in myopic LASIK in different eyes of the same patient

Purpose: To verify whether there exists any difference in higher order aberrations after undergoing myopic LASIK (laser in situ keratomileusis) with conventional ablation and customized ablation in different eyes of the same patient. Methods: This was a prospective randomized study of 54 myopic eyes (27 patients) that underwent LASIK using the Nidek EC-5000 ex-cimer laser system (Nidek, Gamagori, Japan). Topography-guided customized aspheric treatment zone (CATz) was used in the first eye of the patient (study group) and the other eye of the same patient was operated on with conventional ablation (control group). Higher order aberrations [root-mean-square (RMS) in the 5-mm zone] of both groups were observed with the Nidek OPD-Scan aberrometer before and 3 months after LASIK. Preoperative mean refractive error was similar between two eyes of the same patient (t=?0.577, P>0.05). Results: Preoperatively, higher order aberrations (RMS in the 5-mm zone) in the CATz ablation and conventional groups were (0.3600±0.0341) μm and (0.2680±0.1421) μm, respectively. This difference was not statistically significant (t=1.292, P>0.05). Three months after LASIK, higher order aberrations (RMS in 5-mm zone) in the CATz ablation and conventional groups were (0.3627±0.1510) μm and (0.3991±0.1582) μm, respectively. No statistically significant difference was noted between pre- and postoperative higher order aberrations in the CATz group (t=?0.047, P>0.05). However, a statistically significant increase in higher order aberrations was observed after conventional ablation (t=?5.261, P<0.05). A statistically sig-nificant difference was noted in the increase of higher order aberrations after LASIK between groups (t=?2.050, P=0.045). Con-clusion: LASIK with conventional ablation and topography-guided CATz ablation resulted in the same BSCVA (best specta-cle-corrected visual acuity) 3 month after LASIK. Higher order aberrations were increased, but the increase of higher order ab-errations after customized ablation treatment was less than that after conventional ablation.