输电塔塔-线体系风振反应分析

以5A-ZM2型500kV输电塔塔-线体系为例，建立了塔-线体系ANSYS三维有限元分析模型。依据谐波合成法生成作用在输电塔塔-线体系上的风速时程，在五种攻角风荷载作用下，对输电塔位移、输电线位移、主材应力分布和塔的基底反力进行了计算分析，讨论了输电线与输电塔动力耦合作用对输电塔的影响，并提出一些有益的结论。     

高速公路紧急事件处置现场视频无线传输系统的研究

从高速公路交通事故紧急处置和应急救援的角度出发,在对高速公路交通事故过程、影响因素、紧急处置与救援特点及其信息需求分析的基础上,指出高速公路现有的有线监控系统、CDMA,GPRS系统均无法满足高速公路交通事故紧急处置和应急救援中对视频实时传输的需要。给出了笔者研发的适用于高速公路应急救援现场的基于WLAN的无线视频实时传输系统的基本原理与功能。     

A MULTIOBJECTIVE MODEL FOR REGIONAL WATER QUALITY MANAGEMENT1

ABSTRACT: Linear programming is the simplest of all the optimization techniques used in regional water quality management studies; but the technique can optimize only one goal. When there are multiple goals with the same or different priorities, goal programming is a useful decisionmaking tool. This paper illustrates the application of goal programming to a regional water quality management problem where the following two goals are considered: (1) minimize the total cost of waste treatment, and (2) maintain the water quality goals (dissolved oxygen) close to the minimum level stated in the stream standards.     

MANY RESOURCES,MANY USES: A SYSTEM ANALYSIS APPROACH TO RENEWABLE RESOURCE DEVELOPMENT1

ABSTRACT: Decisionmaking associated with the Nation's 1.7 billion acres of forest and range land has become increasingly complicated because of the rise in competition for resource use and in the awareness of environmental and social effects. This system analysis approach uses four models to synthesize pertinent masses of information into measures of economic, environmental, and social impacts. The system results can be used to help evaluate alternative national programs. The models are:

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WATER MULTIPLIERS - REGIONAL IMPACT ANALYSIS1

A significant research problem is the assessment of impacts associated with growth and/or decline in a regional economy. A relevant method for analyzing such problems is the Leontief input/output model. Associated with these models are economic multipliers measuring total changes in sales, income, and employment. In this paper, the author contends resource multipliers are equally relevant. The specific form of these multipliers are defined. Water multipliers for a two-county region in central Nevada are presented and their uses described.     

The interaction between some human obstacles and birds

Some of the literature pertinent to the interactions of birds of flight and man made obstacles, such as transmission lines is reviewed here. Some birds use these towers, poles, and buildings for nesting and perches. They also collide with them. Original observations presented here suggest that the environmental impacts of these types of obstacles on birds, and vice-versa, seem not due to the inability of the birds to perceive the obstacles, but rather that the birds are apparently distracted from a safe flight pattern by their own species, or by others. Editor's Note: Although this paper is quite specialized in comparison with many other articles published in Environmental Management, I feel it is a very useful overview of the problems and the literature related to bird collisions with manmade obstacles. It is hoped that the information presented by the Willards will be helpful to other workers who are perhaps engaged in preparing environmental impact statements concerning structures that could invite bird collisions.     

Energy analysis and the coupling of man and estuaries

New concepts and insights concerning human and natural systems in the coastal zone are emerging from recent energy analysis and synthesis studies. By using new concepts for measuring the quality of energy, one can express the work of ecosystems and human economies in equivalent terms. From energy models and new energy quality evaluations, one can learn what kinds of coastal systems maximize power, are competitive, economically vital, and likely to have a survival advantage.Energy analysis and synthesis is aided by energy circuit diagrams. Models of the coastal zone that emphasize the change in external driving functions related to world energy sources provide insights and some predictive abilities that are not found in economic studies, since money flows alone do not evaluate external driving energies.This paper suggests four procedures for coastal planning: 1) calculation of investment ratio in units of equal quality to determine which projects are economic in a broad sense, 2) development of energy signatures for coastal ecosystems, 3) determination of which interface ecosystems develop the best energy flows, and 4) development of regional models that include the main features of human and natural ecosystems.     

COMPARING METHODS OF HYDROLOGIC REGIONALIZATION1

ABSTRACT: Data splitting is used to compare methods of determining “homogeneous” hydrologic regions. The methods compared use cluster analysis based on similarity of hydrologic characteristics or similarity of characteristics of a stream's drainage basin. Data for 221 stations in Arizona are used to show that the methods, which are a modification of DeCoursey's scheme for defining regions, improve the fit of estimation data to the model, but that is is necessary to have an independent measure of predictive accuracy, such as that provided by data splitting, to demonstrate improved predictive accuracy. The methods used the complete linkage algorithm for cluster analysis and computed weighted average estimates of hydrologic characteristics at ungaged sites.     

酒泉地区城镇体系可持续发展构想

酒泉地区城镇类型较多，城镇体系中的许多关系需要统筹协调，本文侧重从城镇的规模和空间关系分析，城乡一体化和区一发展，基础产业和环境建设等三个角度，探讨了区域城市可持续发展问题。