髋臼骨折的CT诊断价值(附89例分析)

目的：评价CT在髋臼骨折中的诊断价值。方法：回顾分析89例髋臼骨折的CT检查并与X线平片相比较。结果：CT检查在髋臼骨折分型诊断、关节腔内游离碎骨片等方面优于X线平片。结论：CT是全面评价髋臼骨折的必要手段，其总体效能优于X线平片。     

关于线性规划问题解的讨论

用矩阵的奇异值分解和广义逆讨论标准线性规划问题解的存在性和唯一性问题。     

气泡塔熔融结晶器中传递与晶层生长

分析了气泡塔结晶器熔融结晶过程中自熔体向晶层界面的热、质传递特征，建立了描述该过程晶层生长的稳态模型。在自熔体向晶层界面对流传热膜系数的计算中，将弹单元分为弹状气泡周围液膜区、尾迹区及液塞段3段，各段的平均对流传热膜系数不同。分别在表观气速0.04和0．08m/s下，用模型对己内酰胺晶层生长进行了计算，计算结果与实验结果基本吻合。     

叠加势V(r)=A_1r~6+A_2r~2+B_2r~(-4)+B_1r(-6)径向Schrdinger方程的解析解

采用连分法得到了幂函数与逆幂函数V(r)=A1r6+A2r2+B2r-4+B1r-6的叠加势径向Schrodinger方程的 解析解.     

Classification of Medical Brain Images

Since brain tumors endanger people‘s living quality and even their lives, the accuracy of classification becomes more important. Conventional classifying techniques are used to deal with thosedatasets with characters and numbers. It is difficult, however, to apply them to datasets that include brain images and medical history (alphanumeric data), especially to guarantee the accuracy.For these datasets, this paper combines the knowledge of medical field and improves the traditional decision tree. The new classification algorithm with the direction of the medical knowledge not only adds the interaction with the doctors, but also enhances the quality of classification. The algorithm has been used on real brain CT images and a precious rule has been gained from the experiments. This oaoer shows that the ahzorithm works well for real CT data.     

The age of formation of the mirabilite and sand wedges in the Hexi Corridor and their paleoclimatic interpretation

The Hexi Corridor is located at the transition zone of the Asian summer monsoon and westerly airflow, and lies in an important position in terms of its ecological fragility and climatic sensitivity. During a recent field expedition to this region, we found a sedimentary mirabilite layer in a number of localities including Suwushan, Yanchi, Baitujing, Yanchi Gaotai, Huahai, Yumen, Halanuo扙r, and Dunhuang (Fig. 1), which have the potential to provide important information about environmenta…     

Loess-soil sequences in southern Anhui Province： Magnetostratigraphy and paleoclimatic significance

Two parallel loess-soil sequences from Xuancheng and Fanchang in southern Anhui Provinces are dated using geomagnetic and luminescence methods.The Brunhes/Matuyama(B/M) reversal boundary is recognized within the lower part of the so-calles Vermiculated Red Soil (VRS) in the Xuancheng section while the entire Fanchang sequence is of Brunhes age.This indicated that the most recent VRS in southern China,a stratigraphic marker and an indication of extremely warm-humid conditions,was formed during the middle Pleistocene,chronologically correlative with the S4 and S5 soil units in northern China.Microscopic and sedimentologic in vestigations reveal that eolian deposition started in this region at about 0.85 MaBp,roughly synchronous with the well-known Mid-Pleistocene climate change of global significance.The strengthening of both summer and winter monsoon circulations and the consequent river hydrological changes at that time would have provided favorable conditions for sustained eolian deposition in the middle-lower reaches of the Yangtze River since 0.85 MaBP.     

基于自适应逆控制技术的船舶操纵仿真控制

对自适应逆控制理论中的对象动态控制问题和对象扰动控制问题分别进行了探讨，并且针对船舶模型特性，改进了自适应逆控制的框图，使其能够更好地应用于船舶操纵控制。在算法上用最小二乘法代替LMS(Least Mean Square)算法对船舶进行模型参数辨识和控制器的设计。仿真结果表明，改进后的自适应逆控制算法能适应船舶数学模型的变化，与PID控制相比，这种算法具有动态响应快，抗扰动性好等特点。     

整环上Drazin逆的存在性

讨论了整环上Drazin逆的存在性,并且给出了一些充分必要条件,进一步讨论整环上Drazin逆的存在性,并且给出了另一个充分必要条件,即对某个正整数k,R(A~k)( )N(B~k)=R~n。     

单光子发射断层成像散射解析模型的快速算法

为校正单光子发射断层成像(SPECT)中Compton散射的影响,对投影过程进行了解析建模计算。对相机参数进行预计算形成查找表,结合初始放射源活度和散射媒质分布计算得到投影中的原发光子和一次散射光子分布。用数论方法计算查找表中的高维数值积分,使计算速度提高。分别用解析建模方法和Monte-Carlo程序对均匀模型和胸腔模型进行投影计算,比较其相对误差、归一化方差和计算时间。结果表明:解析建模方法的精度与Monte-Carlo方法相当,而计算速度快8倍,可以满足临床需求。