摘要:

A binary liquid crystals system of cholesteryl oleyl carbonate and cholesteryl nonanoate (CN) has been studied using a differential scanning calorimeter. Measurements of the phase transition enthalpies, entropies, and heat capacities indicate that the smectic mesophase appears throughout the whole concentration ranges under cooling, but it only exists at room temperature with CN content of less than 50%. The phase diagram points out that the two components mixed well with ramdon distribution and formed a solid solution. Phase transition temperatures increase monotonically with the increase in CN content. This phenomenon has been interpreted from the viewpoint of molecular configuration. Mixtures have no eutectic point but the mesomorphous ranges of suitable compositions are still notably larger than those of pure components. The most suitable compositions and the most appropriate conditions for the cholesteric formations are also determined.

ISSN:0253-3839    

DOI:10.1080/02533839.1990.9677235

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

This paper addresses a new problem of aligning two rows of movable terminals in order to minimize the channel width and via usage in the channel. The alignment problem of movable terminals is subject to the constraint that the number of vertical tracks used is not increased in the process. This constraint is not considerated in the paper referred to [6] which first considered the alignment problem of movable terminals. This problem is first shown to be NP‐complete, therefore, we present a heuristic algorithm. All examples presented in [2] including Deutsch's difficult example are used as the test routing problems. The programs were coded inCand implemented onSUN 3/110workstation.

ISSN:0253-3839    

DOI:10.1080/02533839.1990.9677236

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

Banyan networks are applicable for interconnecting memory and processor modules in multiprocessor systems as well as for packet switching in communication networks. This paper develops a queueing model for analyzing asynchronous buffered multistage networks. We assume that message inputs form a Poisson process. Each message consists of a geometrically‐distributed number of packets. The transmission time for each packet is generally distributed. Closed‐form expressions for the mean and variance of the number of packets stored at each node and the average time for a packet to traverse a network are obtained. It is shown that under light and medium traffic conditions, analytic and simulation results are in close agreement.

ISSN:0253-3839    

DOI:10.1080/02533839.1990.9677237

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

ISSN:0253-3839    

DOI:10.1080/02533839.1990.9677223

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor