基于ESPO算法的装甲部队城市道路机动路径选择

现代条件下的城市作战,装甲部队的机动性能起着十分重要的作用。由于城市具有纵横交错的道路以及较多的障碍物等特点,使装甲部队的机动性能会受到很大的影响,延误战斗的时间。本文在分析了城市道路对装甲部队机动影响基础上,介绍了ESPO算法的基本原理,建立了装甲部队在城市道路中机动的最短路线选择的数学模型,并通过实验进行验证。     

An assessment of gully erosion along major armoured roads in south-eastern region of South Africa: a remote sensing and GIS approach

An assessment of gully erosion along road drainage-release sites is critical for understanding the contribution of roads to soil loss and for informed land management practices. Considering that road-related gully erosion has traditionally been measured using field methods that are expensive, tedious and limited spatially as well as temporally, it is important to identify affordable, timely and robust methods that can be used to effectively map and estimate the volume of gullies along the road networks. In this study, gullies along major roads were identified from remotely sensed data sets and their volumes were estimated in a Geographic Information Systems environment. Also, the biophysical and climatic factors such as vegetation cover, the road contributing surface area, the gradient of the discharge hillslope and rainfall were derived from remotely sensed data sets using Geographic Information Systems techniques to find out whether they could explain the morphology of gullies that existed in this area. The results of this study indicate that hillslope gradient (R²?=?0.69, α = 0.00) and road contributing surface area (R²?=?0.63, α = 0.00) have a strong influence on the volume of gullies along the major roads in the south-eastern region of South Africa, as might have been expected. However, other factors such as vegetation cover (R² = 0.52, α = 0.00) and rainfall (R² = 0.41 and α = 0.58) have a moderately weaker influence on the overall volume of gullies. Overall, the findings of this study highlight the importance of using remote sensing and Geographic Information Systems technologies in investigating gully erosion occurrence along major roads where detailed field work remains a challenge.     

聊城水化站数字化仪器的安装、运行及评价

介绍了仪器安装前的基础改造工作以及仪器运行状况。实践证明，搞好基础技术改造，创造良好的工作环境是提高仪器观测精度和抗干扰能力的重要举措。     

Impact of hydroelectric power releases on the morphology and sedimentology of the bed of the Warche River (Belgium)

The Butgenbach dam on the Warche River was built in 1932 in order to maintain a suf?cient supply of water to the Robertville reservoir situated 7 km downstream, for the production of hydroelectricity. During winter months, releases are made almost every day from the Butgenbach dam. From a hydrological point of view, this has resulted in signi?cantly reducing the number of discharges that are higher than bankfull. Despite the reduction in peak discharge, there is a signi?cant increase in the number of ef?cient discharges (0·6 bankfull). The impacts of these hydrological modi?cations on the bed morphology and sedimentology below the Butgenbach dam have been studied and the following geomorphological modi?cations have been identi?ed: a doubling of the width of the channel in 45 years, a reduction in the number of rif?es and pools, an increase in the number of gravel bars and islets and an increase in bedrock outcrops in the channel. Moreover, the ?nest bed particles are mobilized by the almost daily releases, inducing a signi?cant increase in bed‐material size sorting. The reduction of sinuosity and the disappearance of bed differentiation and rif?e/pool sequences have produced a diminution of bed roughness and an increase of the competence of the river. Thus relatively small ?oods can remove the armoured layer. Copyright © 2003 John Wiley & Sons, Ltd.     

Morphological development of the retention basin “Hartheim”: A case study

Flow in rivers and on floodplains is complex as it is affected by several interconnected factors such as topography, sediment transport and vegetation characteristics. The resulting processes are explained by the measure “Hartheim” planned for retention purposes at the Upper Rhine river. On the basis of existing formulas and instruments it is demonstrated that a good estimation of the development of the measure is possible. The proposed procedure is a useful tool for estimating morphological developments of restored river sections.     

The Effect of the Propeller Jet on Pile Groups简

The objective of this study is to determine the effect of jet propeller on the damage of berthing structures combined of armoured slope with pile groups. For this purpose, scour measurements were performed for four types berthing structures, which were armoured slope with tandem arrangements of piles for two and three piles and with side by side arrangements of piles for two and three piles. The effect of gap between piles on damage was investigated. The damage level induced by propeller jet between piles was determined. The gaps were 1, 2, 3, and 4 times the pile diameter. Three different values of Rpm （690, 820, and 950） were chosen for the tests. The diameter of circular piles is 40 mm. The slope ratio was 1/3 and the diameter of propeller was 10 cm.