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131.
Mackinson S 《Environmental management》2001,27(4):533-545
Attempting to predict the spatial dynamics fish stocks, as required for management, is an ominous task given our incomplete
understanding of biological and ecological mechanisms underpinning behavioral responses of fish. Large gaps still exist in
our basic scientific knowledge. Nonetheless, the knowledge of fishers and fishery managers is not incorporated into our scientific
analyses, even though such information is rich in observation since knowledge of fish behavior and distribution is a prerequisite
for their profession. Combining such observations with more conventional scientific studies and theoretical interpretations
provides a means by which we may bridge some gaps in our knowledge. Presented here is an example of how both local and scientific
knowledge can be integrated in a heuristic model. The model, CLUPEX, is developed in the framework of a fuzzy logic expert
system and uses linguistic statements written in natural language to capture and combine knowledge sources in the form of
IF … THEN rules. The rules are inferred from interviews with experts and fishery professionals including fishers, fishery
managers, scientists, and First Nations people. The knowledge base, comprised of the set of rules, is flexible in the sense
that it can easily be modified to add additional information or change current information. Using input pertaining to biotic
and abiotic environmental conditions, CLUPEX uses the rules to provide quantitative and qualitative predictions on the structure,
dynamics and mesoscale distribution of shoals of migratory adult herring during different life stages of their annual life
cycle. 相似文献
132.
本文研究了地下管道系统的震害预测及网络系统可靠性分析的方法。它是以地下管道微观破坏机制为根据,以模糊图论为主要计算工具的计算方法。最后,本文给出了天津市煤气管网系统的应用实例,结果表明,本方法有一定的推广应用价值。 相似文献
133.
Weather, climate, and flood predictions are incorporated into human decisions in a wide variety of situations, including decisions related to hazardous hydrometeorological events. This article examines ethical aspects of such predictions and decisions, focusing on the case of the 1997 Red River flood in Grand Forks, North Dakota and East Grand Forks, Minnesota (US). The analysis employs a formal ethical framework and analytical method derived from medical and business ethics. The results of the analysis highlight issues related to forecast generation, communication of forecast meaning and uncertainty, responsibility for the use of forecasts in decision making, and trade-offs between the desire for forecast certainty and the risk of missed events. Implications of the analysis for the broader arenas of weather, climate, and flood prediction and disaster management are also discussed. 相似文献
134.
瑞利波预测煤与瓦斯突出 总被引:1,自引:0,他引:1
瑞利波勘探是近年来发展起来的一种新型的岩土原位测试勘探方法。笔者重点对瞬态瑞利波相速度的算法进行了研究。提出了对信号进行预先调制 ,随后再对所求得的相位进行修正的方法 ;另为还须考虑其仪器采集信号时的时间差影响。根据以上算法求得的相速度更接近瑞利波真速度 ,从而提高了相速度的分辨率和精确度。把瞬态瑞利波勘探法运用在矿山生产中 ,利用平面瑞利波的频散特性 ,根据瑞利波的传播速度与煤岩的物理力学性质具有相关性 ,提出了一种新型的预测煤与瓦斯突出的方法。为矿井安全生产预测预报瓦斯突出提供了一种新的手段 ,同时对突出煤层掘进前方突出危险区和安全距离的分析判断提供了一种新的方法 相似文献
135.
煤与瓦斯突出预测技术研究现状及发展趋势 总被引:42,自引:7,他引:35
对矿井煤与瓦斯突出预测方法的研究现状及发展趋势进行了论述及分析。目前我国大量使用的是钻屑量S、钻孔瓦斯涌出初速度q、瓦斯解吸指标Δh2 、瓦斯放散指数ΔP等钻孔静态预测方法 ,这些方法花费大量的人力、物力和财力 ,而且准确性较低。而声发射和电磁辐射等方法是很有前途的预测方法。未来煤与瓦斯突出预测的发展趋势是 ,利用声发射监测技术对变形破裂剧烈区域进行定位 ,利用电磁辐射监测技术工作面非接触连续预测 ,再结合现有的环境监测系统监测的瓦斯动态涌出对煤与瓦斯突出现象进行准确预测 相似文献
136.
城市固体废物的灰色预测与评价 总被引:9,自引:1,他引:9
对城市固体废物中长期预测,由于影响因素较复杂,采用常规回归分析模型预测,一般精度较低,且要求数据充分。采用灰色预测模型,以杭州市固体放心物历年实际数据进行拟合性预测。结果表明,该模型对城市固体废物作中长期预测,其预测的准确率可达93-99%之间,能较好满足环境规划预测的需要。 相似文献
137.
水中硫化氢的溶解规律 总被引:2,自引:0,他引:2
对气体在水中的溶解机制进行了分析,并结合实验数据导出了硫化氢在水中溶解度的预测公式,该预测公式准确度较高,其平均绝对误差及平均相对误差分别为0.026g/L和0.062%. 相似文献
138.
139.
介绍了倍九律的科学内函以及在地震预报实际应用中的几个主要方面;进而对1983年5月26日日本海中部Ms=7.7级大震前的无震应变前兆的倍九天特征进行了分析,同时探讨了倍九律在日本海地区预报强余震的可参考性。 相似文献
140.
This article summarizes the views of aquatic scientists who gathered to assess the ability of stream ecosystem theory to predict
recovery from disturbance. Two views of disturbance were evident: a discrete removal of organisms vs an unusual deviation
from normal. These were perceived as applying to different scales and/or objectives. Long-term information is required from
both points of view to define recovery. Recovery also may be defined in different ways, but it is clear that recovery has
both spatial and temporal components, and includes both physical and biological processes. Consensus was very strong that
a major role (and challenge) for theory lies in the understanding of spatial aspects, temporal scales, coupling of physics
and biology, and the interaction of these features in recovery processes. Some progress is evident in the articles of this
volume, but among the topics identified as critical for further theoretical contributions were: homogeneous vs heterogeneous
distribution of disturbance, local extent of disturbance relative to a regional context, critical vs noncritical patches (size
and location) of disturbance at different spatial scales and temporal frequencies, delineation of reversible and nonreversible
processes, and physical and biological constraints on the time frame for recovery. Such concepts need attention across different
types of lotic ecosystems. Thus, there was strong consensus that a national monitoring system of representative lotic ecosystems
within ecological regions be established. The purpose of this monitoring system would be to acquire long-term data on natural
variability, to establish viable indicators of spatial and temporal aspects of recovery, and to develop and test emerging
theoretical developments. 相似文献