再生式液体药火炮内弹道过程的多维多相流数值模拟

建立了再生式液体药火炮内弹道过程的多维多相流模型，详细考虑了内弹道过程中多相流区域发生的各种行为，以３７ｍｍ再生式液体药火炮为对象，给出并分析了其内弹道性能参量及其时空分布的数值计算结果。     

Distributing and revoking access authorizations on abstract objecs: A capability approch

In this paper a capability addressing environment is presented, based on the concept of extended capability. First of all it is shown that such an environment is well suited for implementing objects of abstract type. Then the problem of distributing and revoking access authorizations on abstract objects is considered and an efficient solution is presented. The revocation mechanism results in being selective, transitive and deferred.     

2-D FFT algorithm by matrix factorization in a 2-D space

A new 2-D FFT algorithm is described. This algorithm applies a 2-D matrix factorization technique in a 2-D space and offers a way to do 2-D FFT in both dimensions simultaneously. The computation is greatly reduced compared to traditional algorithms. This will improve the realization of a 2-D FFT on any kind of computer. However its good parallelism will especially benefit an implementation on a computer with hypercube architecture. A good arrangement of parallel processors will save a great deal of running time. Furthermore this algorithm can be extended toM-D cases forM>2.Supported by NSF Grant CCR-8813493.Supported by Grants DMS-8607687, DMS-8722402, and DMS9002019.     

Two-level pipelined systolic array for multidimensional convolution

This paper describes a systolic array for the computation of n-dimensional (nD) convolutions for any positive integer n. Systolic systems usually achieve high performance by allowing computations to be pipelined over a large array of processing elements. To achieve even higher performance, the systolic array described in this paper uses a second level of pipelining by allowing the processing elements themselves to be pipelined to an arbitrary degree.     

Measurement and simultaneous compression of multidimensional -ray histograms using address randomizing transforms

In the paper we present efficient algorithm for measurement and simultaneous compression of multidimensional symmetrical γ-ray histograms from event data streams. The compression of data volume is achieved due to both the symmetry of the γ-ray spectra and compression capabilities of the employed randomizing transform. The algorithm of compression is very fast. Acquired compressed data can be later processed in an interactive way.     

The optimal stochastic control of an epitaxial process unit

The problem of computerized batch control of the silicon epitaxial layer deposition technological process has been solved using optimal stochastic control methods. A control algorithm is presented the main emphasis being given to the forecasting and compensating of disturbing processes which act on a process unit under real operation conditions. The method of multidimensional time series, stochastic model form identification for the process noise is developed based on multidimensional time series, correlation analysis results. The “maximum likelihood” identification method is applied in order to obtain efficient estimates of the model parameters. The identification of the model form and model parameters is carried out on the basis of a rather extensive set of data obtained from operation records of a high capacity epitaxial unit. The adequacy of the identified models is checked by means of a correlation analysis of the model residuals. It is demonstrated that results comparable to those with an intuitive process control by an experienced operator, can be achieved when using the algorithm presented in the present work for process computer control. This algorithm thus represents a reliable and rational basis for process control computer software development.     

PMC: Select Materialized Cells in Data Cubes

QC-Tree is one of the most storage-efficient structures for data cubes in an MOLAP system. Although QC-Tree can achieve a high compression ratio, it is still a fully materialized data cube. In this paper, an improved structure PMC is presented allowing us to materialize only a part of the cells in a QC-Tree to save more storage space. There is a notable difference between our partially materialization algorithm and traditional materialized views selection algorithms. In a traditional algorithm, when a view is selected, all the cells in this view are to be materialized. Otherwise, if a view is not selected, all the cells in this view will not be materialized. This strategy results in the unstable query performance. The presented algorithm, however, selects and materializes data in cell level, and, along with further reduced space and update cost, it can ensure a stable query performance. A series of experiments are conducted on both synthetic and real data sets. The results show that PMC can further reduce storage space occupied by the data cube, and can shorten the time to update the cube.     

一种基于DCT域多维格结构的信息隐藏方法

针对目前信息隐藏量和鲁棒性之间难以平衡的问题，提出了一种基于DCT域多维格结构的信息隐藏方法，它对诸如MPEG等各种标准编码技术具有很好的鲁棒性．采用矢量变换和格编码来提高性能，每个视频帧里可以存储大量的信息并符合盲检测的要求．实验结果表明，该方法取得了较好的隐藏效果.     

企业间产品创新多维博弈模型及其分析

在相关文献对典型的Cournot寡头竞争模型论述的基础上,进一步讨论在完全信息条件下两个企业关于具有一定替代性两种产品产量的静态多维Cournot模型及其多维纳什均衡,并得到两个企业分别对每种产品单独博弈时的纳什均衡策略劣于联合考虑这两种产品时进行多维博弈的纳什均衡策略的结果。