Multilevel parametrization for aerodynamical optimization of 3D shapes

We introduce and discuss a combination of methods and options that aim at the aerodynamical optimization of a flow around an arbitrary aircraft shape. The flow is governed by the Euler equations, discretized by a mixed element-volume method on a fixed unstructured tetrahedrization. The shape parametrization relies on the skin of the above mesh through a hierarchical representation. Descent-type and one-shot algorithms are devised and adapted to the solution of a few model problems.     

关于正交设计与均匀设计的比较（Ⅰ）

本文通过对优化效率的比较，说明在主要方面正交设计要比均匀设计更好。     

Optimal monitoring network designs

The selection of a monitoring network is formulated as a decision problem whose solutions would then be optimal. The theory is applied where the underlying field has a multivariate normal probability structure.     

An alternative to ratio method in sample surveys

Summary This paper examines a simple transformation which enables the use of product method in place of ratio method. The convenience with the former, proposed by Murthy [3], is that expressions for bias and mean square error (mse) can be exactly evaluated. The optimum situation in the minimum mse sense and allowable departures from this optimum are indicated. The procedure requires a good guess of a certain parameter, which does not seem very restrictive for practice. Two methods for dealing with the bias of the estimator are mentioned. An extension to use multiauxiliary information is outlined.     

大连广电中心广播电视剧场声学设计

广播电视剧场是随着电视技术的发展和需要而产生的一种新的观演建筑的形式，它不同于一般的演播室，也有别于普通的剧场。它不仅要求能够进行电视节目的转播和录制，还要求能够进行音乐、歌舞等各种文艺节目的演出，并能够举行会议和放映立体声电影，因此，广播电视剧场对音质有很高的要求。本文介绍了大连广播电视中心广播电视剧场的建声设计，在该剧场内采用了计算机控制的可调混响装置，使得各种使用功能都能有一个较为理想的建声环境。     

高效率电磁驱动直线压缩机的研究

本文设计了一台用以驱动热声制冷机的永磁长动圈式无阀型线性压缩机。文章从基本的方程出发给出了线性压缩机设计的思路。在数值计算方面细致地考察了线性压缩机各参数,如动质量、弹簧刚度、频率响应以及声学负载等参数的影响,为实际模型的设计提供了参考。     

Curriculum, Classroom Practices, and Tool Design in the Learning of Functions Through Technology-Aided Experimental Approaches

The paper starts from classroom situations about the study of a functional relationship with help of technological tools as a ‘transposition’ of experimental approaches from research mathematical practices. It considers the limitation of this transposition in existing curricula and practices based on the use of non-symbolic software like dynamic geometry and spreadsheets. The paper focuses then on the potentialities of classroom use of computer algebra packages that could help to go beyond this shortcoming. It looks at a contradiction: while symbolic calculation is a basic tool for mathematicians, curricula and teachers are very cautious regarding their use by students. The rest of the paper considers the design and experiment of a computer environment Casyopée as means to contribute to an evolution of curricula and classroom practices to achieve the transposition in the domain of algebraic activities linked to functions.     

考虑振源阻抗影响的动力吸振器优化设计

本文从四端参数技术入手,着重研究振源特性对动力吸振器优化设计的影响,进行了理论推证。且与传统优化设计进行比较,最后通过回转惯性振源的计算,进行了讨论.     

正交试验设计在麦白霉素高产菌株选育中的应用

本文应用正交试验设计改进了麦白霉素的生产工艺，在四个关键环节上选出了比对照组高出７００μ／ｍｌ以上的高产稳定菌株。该法使试验次数减少，选育周期缩短，既节省了人力物力和降低了生产成本，又增加了麦白霉素药粉的产量，取得了可观的经济效益。