长方体布局问题的一种启发式算法

长方体布局问题属于NP完全问题,在串行机上解决这类问题只能依赖启发式算法。本文提出了一种对布局空间进行动态分解和对剩余空间进行合并和再利用的启发式算法。分解过程采用三叉树数据结构表示,深度优先原则搜索,根据一定的定序规则和定位规则快速求得问题的满意解。同时针对影响布局结果的"难布置的布局物体",设计剩余空间的合并规则,达到该类物体的布入,并通过算例说明了本算法的有效性,对长方体布局具有一定的指导意义,也为人机结合的优化布局提供了良好基础。     

Effect of Fluid-Structure Interaction on Sealed Flow Field and Leakage Rate Based on Computational Fluid Dynamics

This paper addresses the issue of reciprocating compressors staggered labyrinth seal structure. The internal flow field of sealed structure, the displacement of cylinder and piston for different tooth profile angles are analyzed synchronously using FLUENT software, and the effects of fluid-structure interaction on the performance of the labyrinth seal are revealed. The results indicate that with the growth of tooth profile angle, the leakage rate of labyrinth seal tends to decrease first, and then increase. The results of fluid-structure interaction analysis are close to those of actual engineering. The effect of fluid-structure interaction makes tiny deformation in calculation mesh of piston and cylinder structure, and the coupling interaction affects the performance of the labyrinth seal.     

某重型载货车中冷器散热性能改进设计

本文针对某重型载货车中冷器散热能力不足的问题,提出了改进方案,改进散热片结构、改变紊流片尺寸及增加中冷器与水箱之间密封,并通过多种验证方式进行验证,从验证结果看,改进效果较明显,为以后中冷器散热能力的改进提出了参考。     

公路重型自卸车上装结构及技术特点的阐述

重型自卸车市场需求增大,近些年,全国各改装厂对自卸车上装总成结构件进行了一些改进,本文对自卸上装的一些结构特点进行了总结,为同行业从事自卸车上装技术的人员提供参考。     

压力仪表在潜艇上的应用分析

从压力仪表在使用中出现的主要问题入手，结合其发展现状，分析了压力仪表在潜艇上的应用，仔细讨论了仪表供货过程中存在的一些问题，并提出了改进措施。同时，对铅封问题也做了一些说明。     

雾封层技术在低温施工沥青路面中的应用

针对低温施工沥青路面可能产生的水损坏状况,文章提出一种解决方案——雾封层技术。介绍了雾封层的定义及原理,并结合工程应用提出了雾封层施工中需要注意的问题。通过施工前后的对比分析,确定雾封层对沥青路面抗水性能的提高有显著效果。     

纤维稀桨封层技术在沥青路面层养护中的应用

该文分析了稀浆封层的材料要求、条件的选择与室内实验。通过稀浆封层在湖南省长沙市境内沥青路面的某三级公路养护中的运用,阐述了稀浆封层技术的工艺流程及施工注意事项,竣工观测情况,提出了稀浆封层适宜在道路养护中的应用。     

Measurement of ocean temperatures using instruments carried by Antarctic fur seals

The study aimed to test the utility of instruments deployed on marine mammals for measuring physical oceanographic variation and, using this method, to examine temperature variation in the coastal waters around South Georgia. There was a significant correlation between temperature measurements made using a towed undulating oceanographic recorder (UOR) and concurrent measurements from time-depth recorders (TDRs) fitted to lactating Antarctic fur seals foraging from the coast of South Georgia. Congruence was found at horizontal spatial scales from 0.01°×0.01° to 0.5°×0.5° (degrees of latitude and longitude), and at a vertical scale of 10 m. However, there was no significant correlation between temperature measured by TDRs in the top 5 m and sea surface temperature (SST) measured by satellite remote sensing. TDR data provided information about temperature variation vertically through the water column, and through time. The UOR data were used to recalibrate the TDR data in order to correct for the slow response time of the TDR thermistor relative to the speed of seal movements through the water column. Seasonal temperature variation was apparent, and temperatures also varied between regions, and with bathymetry. These results were consistent with the current interpretation of the coastal oceanography around South Georgia. In particular, the relationship between on- and off-shelf waters showed larger amounts of warmer surface water in a region in which more run-off was to be expected. The study also showed that Antarctic fur seals concentrate their activity in regions of colder, and presumably oceanic, water. Such instrumented animals could provide near real time data for assimilation into ocean models.     

消费市场技术变动与现代包装设计的发展

随着现代消费理念、包装目的、包装材料与技术手段的变化,现代包装设计形式与内涵也大大地扩展了。但包装设计不能盲目地追随市场,应理智地沿着可持续的方向发展。     

养护工程中的稀浆封层施工技术

稀浆封层在沥青路面早期养护方面，具有广阔发展前景。通过对稀浆封层设备和施工技术的介绍，章较为清晰地分析了这一新工艺。