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Given the uncertainty in grade at a mine location, a financially risk-averse decision-maker may prefer to incorporate this uncertainty into the ore selection process. A FORTRAN program risksel is presented to calculate local risk-adjusted optimal ore selections using a negative exponential utility function and three dominance models: mean-variance, mean-downside risk, and stochastic dominance. All four methods are demonstrated in a grade control environment. In the case study, optimal selections range with the magnitude of financial risk that a decision-maker is prepared to accept. Except for the stochastic dominance method, the risk models reassign material from higher cost to lower cost processing options as the aversion to financial risk increases. The stochastic dominance model usually was unable to determine the optimal local selection. 相似文献
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We constructed a procurement portfolio for the Indian power sector using two variants of the dynamic conditional correlation GARCH model to derive time-varying correlations between major coal indices. We used prices and qualities of observed cargos to adjust indices for quality gaps as well as for freight costs and power plant efficiency factors. Using the relative homogeneity of the energy content of imports from Australia, South Africa, and Indonesia, we found that the regional seaborne market is highly correlated during normal economic conditions, while suffering brief departures in correlation during demand and supply shocks. Our results show that the buying behavior of power producers is aligned with the mean-variance efficient portfolio of delivered prices using time-varying correlation estimates, but not free-on-board coal index prices. This study challenges the notion that thermal coal importers only source material with a freight price advantage and highlights the importance of coal quality gaps in power production. 相似文献
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湘江新区土地利用结构多目标规划及决策偏好分析 总被引：1，自引：0，他引：1
土地利用规划需要综合考虑经济效益和生态效益。构建了经济最大化和生态效益最大化2个目标,并运用基于模糊集理论的最大(小)算子法求得兼顾经济效益和生态效益的土地利用模糊最优规划方案。随后重点探讨了不同决策偏好情景下的土地利用优化方案和综合效益的变化。研究结果表明:(1)对经济效益和生态效益的偏好程度不同,主要会导致林地、城镇建设用地和水域面积发生变化;(2)随着决策者对生态效益偏好程度的增加,城镇建设用地面积逐渐减少,林地和水域面积逐渐增加;(3)当经济效益比生态效益重要时,最优的用地规划方案主要是在城镇用地和水域面积之间进行权衡;当生态效益比经济效益重要时,最优的用地规划方案主要是在林地和城镇建设用地之间进行权衡。研究结果对湘江新区进行"资源节约型和环境友好型社会"建设中的多目标土地利用规划具有一定的决策参考价值。 相似文献
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Christopher J. Jablonowski Arash Haghshenas Edward E. Shumilak Kenneth F. Tyler 《Natural Resources Research》2017,26(1):57-65
This paper describes the method and results of a probabilistic risk analysis that was used to provide a quantitative basis for a complex and high-stakes design decision for a subsea oil project. Geologic properties were specified as probability density functions based on information from a small number of exploration and appraisal wells. The geological information was coupled to a wellbore fluid dynamics model to simulate operational outcomes for potential well kill operations. Conventional probabilistic sampling and a more efficient experimental design approach were both employed. The key results are cumulative density functions for critical bases of design that are used for risk analysis and final equipment selection. The analysis reinforces the importance of interdisciplinary collaboration, in this case the subsurface disciplines and well engineering, to achieve efficient risk-based designs. 相似文献
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Many kinetic models for oil and gas generation use the same kinetics for generation of both oil and gas. In these models, gas is generated at precisely the same time as oil, despite agreement among geochemists that oil generation in nature largely precedes gas generation. Here we present a method for deriving separate kinetics for oil generation and gas generation from the available kinetics for total hydrocarbon generation. The method is based on published data in which oil kinetics are compiled separately from gas kinetics, but it is generalized to be applicable to any of the main kerogen types (I, IIa, IIb, or III), or to any mixtures of those types. Application of this new nonsynchronous model shows that the traditional synchronous models overpredict gas generation by about a factor of two within the oil window, and conversely severely underpredict late gas generation. The nonsynchronous model may predict gas generation several tens of million years later than does the synchronous model. The errors inherent in the synchronous models can be of significance in exploration decisions. 相似文献
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城市化进程中生态环境响应模型研究——以西安为例 总被引：4，自引：2，他引：2
在建立城市生态环境评价模型,模拟预测城市化过程中引起的土地效益、社会经济发展与生态环境动态变化过程基础上.运用遥感影像解译技术,对城市扩张引起的城市土地利用和土地效益动态变化进行定量分析.采用GIS工具分析城市环境空间分布方式;根据社会福利最大化和绿色GDP(即,GGDP)等理论模拟城市生态环境在不同社会经济情景之下的城市化响应.模型是以西安1996到2006年城市扩张作为案例研究分析,结果表明:在现有的条件下,理论上西安城市扩张最优是在2021;在社会经济不断发展的条件下,城市扩张引起的边际生态环境成本小于平均土地效益时才会增加土地效益;技术进步与创新可降低生态环境成本,使城市化水平提高. 相似文献
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Fatih Döner Rod Thompson Jantien Stoter Christiaan Lemmen Hendrik Ploeger Peter van Oosterom 《International journal of geographical information science》2013,27(7):1173-1189
The increasing complexity and flexibility of modern land use requires that cadastres need to manage information on the third and temporal (fourth) dimension. This article considers the registration of legal space of utility networks in cadastre in this 3D + time (=4D) context. A requirement analysis in three countries that have methods to register utility networks complying with their legal, organizational and technical structure (Turkey, the Netherlands and Queensland, Australia) is the basis for three alternatives for 4D cadastre to register utility networks. The three alternatives are analysed with respect to legal, organizational and technical cadastral requirements. This article presents a case study and a prototype from the Netherlands. In this country by law utilities are considered to be real estate objects with obligatory registration of ownership and geometry. This study shows that the 3D space and separate temporal attributes approach (state-based model) is a very promising solution to maintain temporal changes of utility networks and that this approach is to be preferred above the current practice, where the 3D and temporal aspects are not considered when registering a network. 相似文献
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TELLEZ Ricardo Delgado WANG Shaohua ZHONG Ershun CAI Wenwen LONG Liang 《资源与生态学报(英文版)》2016,7(6):430-438
This paper uses the expected utility under risk hypothesis to develop a new approach to GIS modeling for land use suitability analysis with competitive learning algorithms (CLG-LUSA). It uses Kohonen’s Self Organized Maps (SOM) and Linear Vector Quantization (LVQ) among other tools to create comprehensive ordering of high number of options. The model uses decision makers preferred locations and environmental data to construct a manifold of the decision’s attribute space. Then, decision and uncertainty maps are derived from this manifold. An application example is provided using the selection of suitable environments for coconut development in a municipality of Cuba. CLG-LUSA model was able to provide accurate visual feedback of key aspects of the decision process, making the methodology suitable for personal or group decision making. 相似文献
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Duane Chapman 《Natural Resources Research》1993,2(4):331-339
In theoretical Hotelling-type models of resource depletion, oil use declines monotonically over time to depletion. However, world oil use has been increasing for several years. Can theory and reality be reconciled? The answer is affirmative, if theory is modified to accommodate outward-shifting demand functions that are rising in response to growth in world population and income. Under this assumption, a Hotelling depletion model projects a 50-year period of increasing world oil use before the decline to exhaustion. This holds for both competitive and monopolistic regimes. Hotelling theory has been criticized by Adelman and others, in part because of the unreality of the theoretical projections. By combining the modified Hotelling theory with U.S. Geological Survey resource estimates, the numerical projections seem congruent with Adelman's near-term expectations. Finally, a backstop technology, such as renewable biomass ethanol, introduces a new dimension. Assuming a $2-per-gallon cost for the ethanol, the modified Hotelling theory projects accelerating use of conventional oil until depletion or substitution. Consequently, it does not seem unreasonable to believe that a finite, limited resource of conventional oil is consistent with growing use for several decades. A projected exhaustion in 100 years is consisten with increasing use for 50 years. 相似文献
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目前的土地估价不仅很少考虑地下空间价值,而且缺乏相对成熟的地下空间估价体系和方法。首先结合成本法、收益还原法及楼层效用比法,建立地下空间使用权价格评估模型。然后,分析了地下空间使用权价值的主要影响因素,发现区位、交通、商业经营等因素显著影响地下商业空间的效用;指出为了提高估价的准确性,地下商业空间效用应该分级、分类设置,而不能笼统地确定为同一水平,并据此测算出上海市地下空间使用权地价分配率。基于所构建的评估模型,以上海市地下商业空间为例,通过克里金内插法,廓清了上海市地下空间使用权价格的空间分布状况;最后,从典型购物中心、市级商业中心和全市商业用地成交地块三个维度,探讨上海市地下商业空间使用权价格的空间分异特征。结果表明：① 上海市地下空间使用权价格空间分布与地上土地使用权价格分布规律基本一致,并由市中心向郊区递减;② 地下商业空间使用权价格对地下轨道交通具有较强的依赖性;③ 与地上商业空间使用权价格分布相比,地下商业空间使用权价格分布的集聚性特征更明显。 相似文献
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Filho Francisco Nepomuceno Suslick Saul B. Walls Michael R. 《Natural Resources Research》1999,8(3):193-203
This paper presents a framework to improve the quality of investment decisions in petroleum. The model presented enables the decision-maker to explicitly consider two major objectives when evaluating new petroleum opportunities—financial and technological gain. We utilize MultiAttribute Utility Theory (MAUT) to consider simultaneously the technological challenges of petroleum exploration into the capital budgeting process of an exploration and production firm. The MAUT methodology presented in this work demonstrates that in some mature areas the advantages to exploration are restricted further only to financial gain, based upon the present economic potential of the basin. On the other hand, other seemingly less attractive areas, such as deep horizons in deep-water basins, may represent attractive targets for new exploration as a result of the interaction of financial gain and technological advancement. This advantage reflects the technological gain as a key factor for future operations for oil discoveries in areas with big geological potential. The model presented in this work enables the decision-maker to consider explicitly the risk and rewards associated with both financial and technological payoffs, the decision-maker's tolerance for those types of risks, and the relative importance of each of those objectives in the context of ongoing petroleum exploration decisions. 相似文献
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Danilo J. Santini 《Natural Resources Research》1998,7(2):101-121
This paper examines three issues related to both the U.S. and world oil supply: (1) the nature of the long-term, postpeak
production profile for the U.S. and, by inference, other regions (the Hubbert curve is used as a “strawman” model); (2) implications
on U.S. energy security of using a modified Hubbert-type conceptual model of prepeak production, testing the adequacy of Latin
America to be the primary source of U.S. oil imports; and (3) the cyclic behavior of oil prices. it shows that U.S. production
will exhibit a more attenuated decline than that simulated by the Hubbert curve and not decline to zero. it asserts that U.S.
production is better predicted by past reserves than past production, but that this argument does not apply to nations that
keep a much larger proportion of reserves in the ground. Such nations could considerably expand production without any growth
in reserves. The paper concedes that the potential total production for these nations could be examined with a Hubbert curve
model linked to reserves, but with great uncertainty. Such an uncertain optimistic forecast predicts that the cumulative production
of Latin America could far exceed that of the United States. Nevertheless, a statistical model of oil prices since 1870 implies
that real wellhead oil prices in the United States are on a long-term upward path, underlying a much more “noisy” cyclical
pattern estimated to include 22- and 27-year cycles. The statistical model predicts a severe oil shock within a few years
(of 1998) but also predicts that through 2030, real oil prices will not reach 1981 levels again. The paper examines U.S. and
world trends in seismic exploration, drilling locations and depths, drilling costs, oil/gas reserves, oil/gas use rates, and
oil demand. After taking these factors into consideration, it concludes that the statistical model of oil prices cannot be
disputed, despite its lack of basis in economic theory. 相似文献
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县(市)经济可持续发展决策支撑系统设计研究 总被引：5，自引：0，他引：5
随着区域发展日益成为人们关注的焦点,区域经济的管理水平和决策水平的高低成为制约经济可持续发展的因素之一,尽快建立符合区域经济需要的管理决策支撑系统有其必要性和可能性。本文以县（市）经济管理作为基本的研究对象,从数据库的构造、决策支撑系统的建立、系统的总体框架以及系统模块的组成等方面对区域经济管理决策支撑系统进行了较为全面的设计研究,为进一步的实验工作打下理论基础。 相似文献
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Robert A. Crovelli 《Natural Resources Research》1992,1(2):153-162
A geostochastic system called FASPF was developed by the U.S. Geological Survey for their 1989 assessment of undiscovered petroleum resources in the United States. FASPF is a fast appraisal system for petroleum play analysis using a field-size geological model and an analytic probabilistic methodology. The geological model is a particular type of probability model whereby the volumes of oil and gas accumulations are modeled as statistical distributions in the form of probability histograms, and the risk structure is bilevel (play and accumulation) in terms of conditional probability. The probabilistic methodology is an analytic method derived from probability theory rather than Monte Carlo simulation. The resource estimates of crude oil and natural gas are calculated and expressed in terms of probability distributions. The probabilistic methodology developed by the author is explained.The analytic system resulted in a probabilistic methodology for play analysis, subplay analysis, economic analysis, and aggregation analysis. Subplay analysis included the estimation of petroleum resources on non-Federal offshore areas. Economic analysis involved the truncation of the field size with a minimum economic cutoff value. Aggregation analysis was needed to aggregate individual play and subplay estimates of oil and gas, respectively, at the provincial, regional, and national levels. 相似文献
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Laurent Louvart Alexandru-Liviu Olteanu 《International journal of geographical information science》2013,27(10):1910-1931
While the integration of geographical information systems (GIS) and multicriteria decision aiding (MCDA) has attracted increasing interest from researchers in recent years, due to the wide array of applications that can benefit from GIS as well as the different types of decision problems and various models that can be used through MCDA, plenty of opportunities of integrating GIS and MCDA remain. In this article, we present the result of such an opportunity in the form of a methodology and software that is currently used by the Naval Hydrographic and Oceanographic Service in France. Furthermore, this tool may be used in conjunction with other GIS–MCDA applications with a single decision maker, multiple decision makers or even where the decision has a hierarchical structure. 相似文献
17.
Xiaoping Liu Xia Li Zhangzhi Tan Yimin Chen 《International journal of geographical information science》2013,27(11):1829-1848
Currently, with rapid expanding of urban area, the rate of conversion of agricultural land to nonagricultural uses in China is increasing. Zoning farmland protection is an important measure to protect limited land resource. This article presented an innovative approach based on the integrated use of remote sensing, GIS, and artificial immune systems (AIS) for generating farmland protection areas. Some modifications have been made for conventional AIS so that it can be further extended to the solution of zoning problems. The optimal objective is to generate farmland protection areas that minimize development potential and maximize agricultural suitability and spatial compactness. First, utility function by addressing the criteria of farmland protection is incorporated into AIS algorithm. Second, encoding and mutation of antibodies is modified so that it can be suited to the solution of spatial optimization problems. The AIS-based zoning model was then applied to a case study in Guangzhou, Guangdong, China. The experiments have demonstrated that the proposed method was an efficient and effective spatial optimization technique, which took only about 194 seconds to generate satisfied farmland protection patterns. Furthermore, the AIS-based zoning model can explore various alternatives conveniently, and it can yield better performances than nonprotection scenario in the utility efficiency of land resources and the site condition for farmland. 相似文献
18.
The formation of oil and gas reservoirs is the result of infinitesimal amounts of hydrocarbons that accumulate in sedimentary
basins through a process of chain reactions, which occur one step at a time. The reactions can be divided into a set of interrelated
static factors, which can be divided into a subset of interrelated factors. The chain reactions define a genetic model that
has a layered structure with the property of forward chaining. It is an attempt to portray the process of formation of oil
and gas reservoirs. By using this model in petroleum exploration, potential pool-size distributions can be evaluated. 相似文献
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During the last 30 years, the methodology for assessment of undiscovered conventional oil and gas resources used by the Geological
Survey has undergone considerable change. This evolution has been based on five major principles. First, the U.S. Geological
Survey has responsibility for a wide range of U.S. and world assessments and requires a robust methodology suitable for immaturely
explored as well as maturely explored areas. Second, the assessments should be based on as comprehensive a set of geological
and exploration history data as possible. Third, the perils of methods that solely use statistical methods without geological
analysis are recognized. Fourth, the methodology and course of the assessment should be documented as transparently as possible,
within the limits imposed by the inevitable use of subjective judgement. Fifth, the multiple uses of the assessments require
a continuing effort to provide the documentation in such ways as to increase utility to the many types of users.
Undiscovered conventional oil and gas resources are those recoverable volumes in undiscovered, discrete, conventional structural
or stratigraphic traps. The USGS 2000 methodology for these resources is based on a framework of assessing numbers and sizes
of undiscovered oil and gas accumulations and the associated risks. The input is standardized on a form termed the Seventh
Approximation Data Form for Conventional Assessment Units. Volumes of resource are then calculated using a Monte Carlo program
named Emc2, but an alternative analytic (non-Monte Carlo) program named ASSESS also can be used.
The resource assessment methodology continues to change. Accumulation-size distributions are being examined to determine how
sensitive the results are to size-distribution assumptions. The resource assessment output is changing to provide better applicability
for economic analysis. The separate methodology for assessing continuous (unconventional) resources also has been evolving.
Further studies of the relationship between geologic models of conventional and continuous resources will likely impact the
respective resource assessment methodologies. 相似文献