城市火灾扑救调度指挥过程的Petri网模型研究

在经典Ｐｅｔｒｉ网理论的基础上,发展了一类有色非自主Ｐｅｔｒｉ网方法,用以建立城市火灾扑救调度指挥过程的仿真模型,并通过实例,对火警出动等级判断规则及按火警出动等级调派车辆规则进行了初步仿真研究。     

一种新型的煤气回火安全装置

介绍了一种新型的煤气回火安全装置,说明了它的工作原理,主要参数,工艺结构等,叙述了其研制过程和应用情况。     

矿井外因火灾计算机控制及有待解决的若干问题

针对矿井外因火灾,评价了计算机技术在矿井火灾防治应用中的研究现状,阐述了发展矿井火灾计算机控制技术的重要意义及其应用前景。同时,指出了进一步发展矿井火灾计算机控制技术中有待解决的问题     

超大规模工业厂房突破防火规范问题及其技术研究

超大规模工业厂越来越多地应用于工业生产，但与我国现行防火技术规范存在突出的矛盾，有些地方甚至突破了我国现行防火技术规范。本文即对这一矛盾进行典型事例分析，并研究上应的安全措施。     

峨眉山环境现状研究

峨眉山是世界名山，其主要风景林－－冷杉出现大面积衰败和死亡。本文概述了峨眉山的地理和气候特点，研究了土壤、植被、大气环境及旅游现状；为深入研究峨眉山冷杉衰亡的原因提供基础资料，为恢复和建设峨眉山的生态环境提供思路和参考。     

PREDICTING TEMPORAL AND SPATIAL FLOOD DYNAMICS USING A PRECALIBRATED MODEL1

ABSTRACT: A large storm in December 1990 allowed the evaluation of flood predictions from a hydrologic model (TOPMODEL) that had been previously calibrated on the West Fork of Walker Branch Watershed, a gauged 37.5 ha catchment near Oak Ridge, Tennessee. The model predicts both hydrograph dynamics and the spatial distribution of overland flow using an index based on topography. Maximum extent of overland flow during the storm was determined from patterns of leaf litter removal from valley bottoms. Both the flood hydrograph and the extent of overland flow were accurately predicted using model parameters obtained from a three-month period of normal flow conditions during 1983.     

Forest service experience with interdisciplinary teams developing integrated resource management plans

The National Forest Management Act and National Environmental Policy Act require the use of an interdisciplinary team (ID team) to do integrated resource planning for the National Forests and the concurrent environmental analysis. A survey sent to all National Forest planning officers (82% response) reveals the composition of the ID teams used in integrated resource and land management planning. More than half the National Forests ID teams met NEPA and NFMA compositional requirements. National Forest planners recount their experiences with these ID teams. Despite frustrations with many aspects of the ID teams, the planners strongly support the idea that ID teams are an important part of the land-use planning process and think that their use leads to better National Forest integrated resource plans.     

Restoring naturalness to national parks

National park resource management planning requires ecological information describing the objectives to be achieved. This information must be quantitative and unambiguous. Since most acts creating United States national parks, beginning with the Yellowstone National Park Act of 1872, specify that these parks should be maintained in a natural condition, resource management objectives for each national park must be defined in terms of quantitative standards of naturalness. Such quantitative standards of naturalness do not yet exist for any national park in the United States. Although this article focuses on US national parks, the same problem exists in national parks, reserves, and wilderness areas throughout the world. The physical evidence needed to develop quantitative standards of naturalness is rapidly disappearing because of the effects of management fires, wildfires, decomposition, successional changes, and other disturbances. Therefore, a nationwide rescue ecology program is recommended to recover as much remaining ecological information as possible before it is lost. This information is essential for developing quantitative standards to restore naturalness to national parks.     

Changes in interacting species with disturbance

Human-influenced changes in the diversity and abundance of native wildlife in a southern boreal forest area, which became a national park in 1975, are used to develop working hypotheses for predicting and subsequently measuring the effects of disturbance or restoration programs on groups of interacting species. Changes from presettlement conditions began with early 1900 hunting, which eliminated woodland caribou (Rangifer tarandus) and elk (Cervus elaphus), and reduced moose (Alces alces) to the low numbers which still persist. Increases in white-tailed deer (Odocoileus virginianus), as these other cervid species became less abundant or absent, provided enough alternative food to sustain the system's carnivores until plant succession on previously burned or logged areas also caused deer to decline. With increased competition for reduced food, carnivore species also became less abundant or absent and overexploited some prey populations. The abilities of interacting species to maintain dynamically stable populations or persist varied with their different capacities to compensate for increased exploitation or competition. These relationships suggested a possible solution to the problem of predicting the stability of populations in disturbed systems. For the 1976–1985 period, a hypothesis that the increased protection of wildlife from exploitation in a national park would restore a more diverse, abundant, and productive fauna had to be rejected.     

SUSPENDED SEDIMENT AND TURBIDITY FOLLOWING ROAD CONSTRUCTION AND LOGGING IN WESTERN MONTANA1

ABSTRACT: Forest management activities in a second order drainage basin increased suspended sediment yields 7.7 fold in the first year following road construction, and two-fold following logging in the second year. Sediment supply limitations resulted in poor correlations between sediment concentrations with discharge. Sediment transport was strongly hysteretic, with the highest sediment concentrations occurring on the rising limbs of snowmelt hydrographs and individual peaks. In addition to discharge, hydrograph characteristics such as limb, dQ/dt, and the product of dQ/dt and limb aided in explaining variability of observed sediment concentrations. Sediment-turbidity relationships were strongly discharge dependent, reflecting the changing composition of the suspended load with stream power and sediment supplies.