合肥市历史文化街区建设研究

基于富有历史文化内涵的特色街区的概念和特征,对合肥特色街区分类、布局以及建设过程中存在问题进行分析,着重介绍和探讨了历史文化街区利用和保护问题,最后从规划设计、合理定位、政府及社会广泛参与等几个方面,提出了历史文化街区建设的对策建议。     

The mad estimator: when is it non-linear? applications to two-way design models

The mean absolute deviation (MAD) estimator has recently received a great deal of attention as applied to full-rank linear regression models. This paper provides a necessary and sufficient condition for the MAD estimator to be a non-linear estimator, in which case conditions for the variance of the MAD estimator to be larger or smaller than those for OLS are, in general, unknown. The non-linearity of the MAD estimator is examined for several two-way designs; in particular (1) randomized block design (2) two-way nested design (3) two-way classification with interaction and (4) partially balanced incomplete block design     

On the recovery of intra- and interblock information in n-ary designs

This note presents an extension of Q-method of analysis for binary designs given by Rao (1956) to n-ary balanced and partially balanced block designs. Here a linked n-ary block (LNB) design is defined as the dual of balanced n-ary (BN) design. Having a note on Yates’ (1939, 1940) method of P-analysis, we further extend the expressions for binary linked block (LB) designs given by Rao (1956) to linked n-ary block (LNB) designs which admit easy estimation of parameters for these type of all n-ary designs.     

Flexible regression modeling

The author proposes a new method for flexible regression modeling of multi‐dimensional data, where the regression function is approximated by a linear combination of logistic basis functions. The method is adaptive, selecting simple or more complex models as appropriate. The number, location, and (to some extent) shape of the basis functions are automatically determined from the data. The method is also affine invariant, so accuracy of the fit is not affected by rotation or scaling of the covariates. Squared error and absolute error criteria are both available for estimation. The latter provides a robust estimator of the conditional median function. Computation is relatively fast, particularly for large data sets, so the method is well suited for data mining applications.     

旋转体表面摩擦力矩探讨

本文绘出了非跑合情况下由一般曲线所产生的旋转体表面和与其相配合的毂孔表面作相对匀速转动时，相对运动表面摩擦力矩计算的一般公式。     

Bellman-Ford算法的改进研究

针对传统距离矢量路由(Bellman-Ford)算法,将多约束路由问题简化,并改进路由问题的限制条件,提出了改进的Bellman-Ford算法,应用于基于集中式控制路由协议网络模型。仿真结果表明,采用改进算法的网络路由计算时间随网络节点数有明显的改善,且网络阻塞率随路由请求数增加而下降。验证了改进算法比传统算法更加有效。     

On the block structure of proper block designs

In this paper we consider proper block designs and derive an upper bound for the number of blocks which can have a fixed number of symbols common with a given block of the design. To arrive at the desired bound, a generalization of an integer programming theorem due to Bush (1976) is first obtained. The integer programming theorem is then used to derive the main result of this paper. The bound given here is then compared with a similar bound obtained by Kageyama and Tsuji (1977).     

沿海地区集聚式城市化地域扩张模式及优化

结合我国长三角、珠三角和环渤海湾新型城市化模式的具体案例，分析集聚式城市发展的动力机制和地域扩张模式，认为产业集聚已成为推动沿海区域城市化进程的重要驱动力。论题针对沿海区域集聚式城市化模式存在的问题提出了具体的对策建议。     

通用型阶梯式可转位端铣刀试验与研究

本文利用阶梯切削法原理，研究径向错移量较大的单组阶梯式铣削方法，进行了阶梯式可转位端铣刀结构设计计算公式的推导，并做了大量的切削性能对比试验，试验结果与预测指标相符。     

Complete designs with blocks of maximal multiplicity

The set of distinct blocks of a block design is known as its support. We construct complete designs with parameters v(?7), k=3, λ=v ? 2 which contain a block of maximal multiplicity and with support size $\text{b}{}^1\text{= (}{}^{\mathrm{v}}{}_3\text{) ? 4(v ? 2)}$. Any complete design which contains such a block, and has parameters v, k, λ as above, must be supported on at most (^v₃) ? 4(v ? 2) blocks. Attention is given to complete designs because of their direct relationship to simple random sampling.