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591.
Value of information analysis for adequate monitoring of carbon dioxide storage in geological reservoirs under uncertainty 总被引:1,自引:0,他引:1
Kozo Sato 《International Journal of Greenhouse Gas Control》2011,5(5):1294-1302
As monitoring is essential for the proper management of geological storage of carbon dioxide (CO2), the ability to value information from monitoring is indispensable to adequately design a monitoring program. It is necessary to judge whether the expected improvement in management is worth the cost of monitoring. The value of information (VOI) is closely related to the possible increase in expected utility gained by gathering the information, the concept of which can be applied to such judgement. Although VOI analysis has been extensively studied in the context of decision analysis, its application to the management of carbon dioxide capture and storage (CCS) operations is rare. This paper introduces and discusses the methodology of VOI analyses in the context of monitoring CO2 storage. A motivating problem with discrete probabilities is used to illustrate the concept of VOI. It is demonstrated that information is not always of value; for information to be worthwhile, monitoring under uncertainty must satisfy certain conditions. This concept is then extended to continuous probability distributions. The effects of prior uncertainty and information reliability on the VOI are examined. It is shown that an excessive improvement in information accuracy yields little value and that the optimal level of reliability can be inferred. VOI analyses provide quantitative insights into the value of information-gathering activities and therefore can be an objective means to adequately design and impartially justify a monitoring program. 相似文献
592.
The value of information is a general and broadly applicable concept that has been used for several decades to aid in making decisions in the face of uncertainty. Yet there are relatively few examples of its use in ecology and natural resources management, and almost none that are framed in terms of the future impacts of management decisions. In this paper we discuss the value of information in a context of adaptive management, in which actions are taken sequentially over a timeframe and both future resource conditions and residual uncertainties about resource responses are taken into account. Our objective is to derive the value of reducing or eliminating uncertainty in adaptive decision making. We describe several measures of the value of information, with each based on management objectives that are appropriate for adaptive management. We highlight some mathematical properties of these measures, discuss their geometries, and illustrate them with an example in natural resources management. Accounting for the value of information can help to inform decisions about whether and how much to monitor resource conditions through time. 相似文献
593.
Z. WangR.F. Grant M.A. ArainB.N. Chen N. CoopsR. Hember W.A. KurzD.T. Price G. StinsonJ.A. Trofymow J. Yeluripati Z. Chen 《Ecological modelling》2011,222(17):3236-3249
Forest productivity is strongly affected by seasonal weather patterns and by natural or anthropogenic disturbances. However weather effects on forest productivity are not currently represented in inventory-based models such as CBM-CFS3 used in national forest C accounting programs. To evaluate different approaches to modelling these effects, a model intercomparison was conducted among CBM-CFS3 and four process models (ecosys, CN-CLASS, Can-IBIS and 3PG) over a 2500 ha landscape in the Oyster River (OR) area of British Columbia, Canada. The process models used local weather data to simulate net primary productivity (NPP), net ecosystem productivity (NEP) and net biome productivity (NBP) from 1920 to 2005. Other inputs used by the process and inventory models were generated from soil, land cover and disturbance records. During a period of intense disturbance from 1928 to 1943, simulated NBP diverged considerably among the models. This divergence was attributed to differences among models in the sizes of detrital and humus C stocks in different soil layers to which a uniform set of soil C transformation coefficients was applied during disturbances. After the disturbance period, divergence in modelled NBP among models was much smaller, and attributed mainly to differences in simulated NPP caused by different approaches to modelling weather effects on productivity. In spite of these differences, age-detrended variation in annual NPP and NEP of closed canopy forest stands was negatively correlated with mean daily maximum air temperature during July-September (Tamax) in all process models (R2 = 0.4-0.6), indicating that these correlations were robust. The negative correlation between Tamax and NEP was attributed to different processes in different models, which were tested by comparing CO2 fluxes from these models with those measured by eddy covariance (EC) under contrasting air temperatures (Ta). The general agreement in sensitivity of annual NPP to Tamax among the process models led to the development of a generalized algorithm for weather effects on NPP of coastal temperate coniferous forests for use in inventory-based models such as CBM-CFS3: NPP′ = NPP − 57.1 (Tamax − 18.6), where NPP and NPP′ are the current and temperature-adjusted annual NPP estimates from the inventory-based model, 18.6 is the long-term mean daily maximum air temperature during July-September, and Tamax is the mean value for the current year. Our analysis indicated that the sensitivity of NPP to Tamax was nonlinear, so that this algorithm should not be extrapolated beyond the conditions of this study. However the process-based methodology to estimate weather effects on NPP and NEP developed in this study is widely applicable to other forest types and may be adopted for other inventory based forest carbon cycle models. 相似文献
594.
为研究集装箱岸桥(QC)装卸作业安全操作机理,利用信息论的理论和方法对岸桥信息处理与传递进行建模和计算。首先总结集装箱装卸作业流程的11个作业环节,以人脑为信道,利用通信系统模型建立岸桥司机装卸作业各环节的信息传输转换模型。基于甘特图思想,建立整个装卸作业流程的刺激-反应流程图;并计算作为刺激的各信息源事件的信息量I(xi),信源熵H(X)和信息传递量HT。根据描述性模型和定量计算结果,对各作业环节提出有针对性的事故预防措施。 相似文献
595.
Joanna Ejdys Agata Lulewicz-Sas 《International journal of occupational safety and ergonomics》2013,19(4):445-454
The concept of an occupational health and safety management system (OH&S MS) has become widespread over the past 20 years. However, there are few studies on the subject, they are generally methodologically weak and in many cases cannot be generalized. A formalized OH&S MS is a set of rules and connected elements of the general organization management system which guarantees accomplishment of the organization?s objectives in the area of upgrading safety conditions of both employees and the environment. The need for research on voluntary management systems stems from the necessity to propagate appropriate solutions and their continuous development processes. This paper discusses an OH&S MS as a source of data and essential information on the process of developing a system. It examines the relationship between the degree to which the requirements of Standard No. PN-N-18001:2004 have been adapted and the demand for health and safety data and information. 相似文献
596.
于乔 《中国环境管理干部学院学报》2013,(5):85-87
把信息技术融入高职英语教学已经成为高职院校英语教学的普遍现象。从高职英语教学现状分析入手,结合学习的联结理论和建构主义理论,论述了信息技术是高职英语教学改革的必然性。详细分析了信息技术在高职英语教学中具有的显著特点和优势,以及信息技术与高职英语教学的整合模式,即情景教学模式、学生主体模式和交互学习模式。在此基础上分别从教师、学生两个角度深入探讨了在英语教学中应用信息技术应该注意的一些问题。通过这些深入的探讨应该看到随着更先进的信息技术引入教育领域,高职英语课堂将更具有吸引力,教师的教学空间将更加开放和富有创意,学生的自主学习将更加宽广和富有弹性。 相似文献
597.
A. Yli-Viikari 《Local Environment》2013,18(10):891-903
This study examines sustainability indicators using the sustainability report of the Finnish Ministry of Agriculture and Forestry as the case study. The report is a compilation of indicators designed to assess the sustainability of natural resource management. The interviews with the users revealed, however, that the indicators have not been particularly effective in informing the actors or in affecting their behaviour. Clearly, the informative value of the indicators has been overrated and the complexity of the information transfer has been underestimated. At least partly, the difficulties were due to the obscurity of the indicator-concept itself and consequently to their improper use. First, the statistics with the objective state-of-affairs information should be distinguished from the indicators that are always related to policy discussion. In addition, the technical and communicative use of the indicators should be distinguished from each other as they have different relationship between the information, policy values and the associated activities. 相似文献
598.
599.
论述了通过遥感技术寻找内生金矿床的可能性。首先 ,讨论了运用遥感技术寻找内生金矿床的基本原理 ;其次 ,提出了运用遥感技术寻找内生金矿床的一些具体方法步骤 ;最后 ;介绍了两个应用实例。 相似文献
600.
处置萌芽状态突发事件的数学模型探讨 总被引:5,自引:0,他引:5
本文应用运筹学方法.从分析突发事件的发生规律入手,建立处置萌芽状态突发事件的数学模型.探讨其环节及对策.为处置突发事件提供定量和定性的分析方法。 相似文献