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1.
Using data on the entire population in combination with data on almost all individuals in Sweden listed as inventors, we study how the probability of being listed on a patent as inventor is influenced by the density of other future inventors residing in the same region. In this process, we control for demographic and sector effects along with the educational characteristics of parents. This approach allows us to trace how location history influences individuals’ inventive capacity. We focus on three types of influences: (a) future inventors in the municipality around the time of birth, (b) future inventors around the time of graduation from high school and (c) future inventors at graduation from higher education. We find suggestive evidence that co-locating with future inventors may impact the probability of becoming an inventor. The most consistent effect is found for place of higher education; some positive effects are also evident from birthplace, whereas no consistent positive effect can be derived from individuals’ high school location. Therefore, the formative influences mainly deriving from family upbringing, birth region and from local milieu effects arising from a conscious choice to attend a higher education affect the choice of becoming an inventor.  相似文献   

2.
Forecasting of recoverable reserves aims to predict the tonnages and grades that will be recovered at the time of mining. The main concern in this forecasting is the imprecision in the selection of ore/waste resulting from both the so-called information effect or information that becomes available during grade control, and the support effect or mining selectivity during mining. Existing approaches to recoverable reserve estimation account for mining selectivity; however, they largely ignore the information effects from future data becoming available through grade control practices. An application at the Morila gold deposit, Mali, is utilized in this paper to document a new simulation-based approach for recoverable reserve forecasting that incorporates the potential effects of future grade control data. This accounts for the information effect as well as changes in data quantity and quality over time. In addition, the case study at the Morila mine elucidates the use of a newer, very efficient, and practical alternative to traditional simulation techniques. This direct block simulation method forecasts recoverable reserves directly into the selective mining unit (support) size under consideration. The case study demonstrates the practical uncertainty assessment of the recoverable reserves within the deposit, so that expected inaccuracies in the selection of ore /waste can be accounted for. This allows for fully informed mining decisions to be made that incorporate the effects of information and selectivity while quantifying the potential impact of uncertainty on the mine operation and its final economic outcome.  相似文献   

3.
A 1 km square regular grid system created on the Universal Transverse Mercator zone 54 projected coordinate system is used to work with volcanism related data for Sengan region. The following geologic variables were determined as the most important for identifying volcanism: geothermal gradient, groundwater temperature, heat discharge, groundwater pH value, presence of volcanic rocks and presence of hydrothermal alteration. Data available for each of these important geologic variables were used to perform directional variogram modeling and kriging to estimate geologic variable vectors at each of the 23949 centers of the chosen 1 km cell grid system. Cluster analysis was performed on the 23949 complete variable vectors to classify each center of 1 km cell into one of five different statistically homogeneous groups with respect to potential volcanism spanning from lowest possible volcanism to highest possible volcanism with increasing group number. A discriminant analysis incorporating Bayes’ theorem was performed to construct maps showing the probability of group membership for each of the volcanism groups. The said maps showed good comparisons with the recorded locations of volcanism within the Sengan region. No volcanic data were found to exist in the group 1 region. The high probability areas within group 1 have the chance of being the no volcanism region. Entropy of classification is calculated to assess the uncertainty of the allocation process of each 1 km cell center location based on the calculated probabilities. The recorded volcanism data are also plotted on the entropy map to examine the uncertainty level of the estimations at the locations where volcanism exists. The volcanic data cell locations that are in the high volcanism regions (groups 4 and 5) showed relatively low mapping estimation uncertainty. On the other hand, the volcanic data cell locations that are in the low volcanism region (group 2) showed relatively high mapping estimation uncertainty. The volcanic data cell locations that are in the medium volcanism region (group 3) showed relatively moderate mapping estimation uncertainty. Areas of high uncertainty provide locations where additional site characterization resources can be spent most effectively. The new data collected can be added to the existing database to perform future regionalized mapping and reduce the uncertainty level of the existing estimations.  相似文献   

4.
Itu Local Government Area is prone to groundwater contamination occasioned by saltwater due to the geographical location and the aquifer unit inter-transmissibility between the communicating/interconnected pores of the water-bearing units. This inter-transmissibility causes the continuous distribution of contamination among interconnected aquifer repositories. The study integrated the surface electric mapping and laboratory analysis of geologic samples and their corresponding water samples in estimating the transmissibility-dependent petrophysical parameters. The functional relationships between parameters have been determined. Maps of the spatial distribution of the estimated geohydraulic parameters have been drawn. Quantitative links of measured parameters to transmissibility have established. The resulting inferences based on the indices or magnitudes of the parameters measured helped in delineating the directions of water transmission within and across the hydrogeological units under study. The inferred result of permeability serves as a guide in identifying the southern zone of the area under study as having relatively reduced hydraulic pressure gradient differential, while the northern region has on the average, high hydraulic gradient differentials. The results of directions of inter-transmissibility of hydrodynamic properties in aquifer units are promising and capable of increasing the depth of knowledge on groundwater contamination and hence provide substantial input parameters that can enhance groundwater modelling within and near the study location.  相似文献   

5.
Sinha  Sudarshana  Basu  Anindya 《GeoJournal》2022,87(4):683-701

This study assesses the disparity in the level of material wellbeing between the rural and urban areas of various districts of West Bengal. To measure the level of material wellbeing three broad domains comprising of Housing index (HI), Basic Amenities Index (BAI) and Asset Index (AI) following which a composite index (Material Wellbeing Indexi.e. MWI) was computed for the urban and the rural areas for all the districts between the time frame of 2001–2011. A set of 14 sub-indicators were selected for the analysis. This paper takes into account the differentials between the urban and the rural areas of the state. The data was subjected to correlation analysis, ANOVA and PCA, intra-zonal analysis was also performed. The results show the presence of widespread levels of disparity between the various districts as well as within the districts. Over the course of the years this disparity has increased in case of the northern zone however intra and inter zonal disparity runs high. Among the different sub-indicators, BAI has recorded the highest decrease in the differentials whereas the AI has recorded the highest increase in the differentials. Among the districts eight of them have recorded a net increase in the differentials in MWI among which Maldah has recorded the highest decrease in the differentials whereas Dakshin Dinajpur has recorded the highest increase in the differentials.

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6.
Sustainable management of groundwater resources is vital for development of areas at risk from water-resource over-exploitation. In northeast Thailand, the Phu Thok aquifer is an important water source, particularly in the Thaphra area, where increased groundwater withdrawals may result in water-level decline and saline-water upconing. Three-dimensional finite-difference flow models were developed with MODFLOW to predict the impacts of future pumping on hydraulic heads. Four scenarios of pumping and recharge were defined to evaluate the system response to future usage and climate conditions. Primary model simulations show that groundwater heads will continue to decrease by 4–12?m by the year 2040 at the center of the highly exploited area, under conditions of both increasing pumping and drought. To quantify predictive uncertainty in these estimates, in addition to the primary conceptual model, three alternative conceptual models were used in the simulation of sustainable yields. These alternative models show that, for this case study, a reasonable degree of uncertainty in hydrostratigraphic interpretation is more impactful than uncertainty in recharge distribution or boundary conditions. The uncertainty-analysis results strongly support addressing conceptual-model uncertainty in the practice of groundwater-management modeling. Doing so will better assist decision makers in selecting and implementing robust sustainable strategies.  相似文献   

7.
通过经营内容选择法、经营方式选择法、经营安排法、投资筹划法等方面进行叙述和研究,根据我国现行税法的规定及企业税后利益最大化的要求,通过经营策划和纳税谋划,对未来纳税义务做出规划,旨在减少企业纳税负担和风险,促进企业利润及价值最大化。  相似文献   

8.
9.
Imposing any tax among carbon tax, sulfur tax and nitrogen tax on fossil fuels will also reduce the other two air pollutants. Neglecting the synergistic effect of each energy environmental tax and levying carbon tax, sulfur tax and nitrogen tax at the same time will overestimate the abatement cost of air emissions. This study adopts a partial equilibrium model which uses linear demand and supply curves to illustrate the emission reductions in carbon tax, sulfur tax and nitrogen tax. The synergistic reduction effects of CO2, SO2 and NO x are firstly evaluated under the implicit tax scenario of resource tax and consumption tax on fossil fuels. Then it is compared with the synergistic reduction effects of CO2, SO2 and NO x under different explicit tax scenarios of increasing tax rate on carbon tax, sulfur tax and nitrogen tax. If the synergistic reduction effect of explicit environmental taxes is better, this research aims to find one kind of environmental tax among carbon tax, sulfur tax and nitrogen tax with the best synergistic reduction effect and to provide a decision support for the policy makers of energy environmental taxes. The results indicate that explicit environmental taxes have better synergistic reduction effects compared with the current implicit environmental taxes. And explicit sulfur tax can lead to the largest synergistic reduction effects of CO2, SO2 and NO x . Therefore, the policy makers of energy environmental taxes could consider adopting the explicit sulfur tax to reduce various environmental air emissions at the largest amount.  相似文献   

10.
A stochastic channel embedded in a background facies is conditioned to data observed at wells. The background facies is a fixed rectangular box. The model parameters consist of geometric parameters that describe the shape, size, and location of the channel, and permeability and porosity in the channel and nonchannel facies. We extend methodology previously developed to condition a stochastic channel to well-test pressure data, and well observations of the channel thickness and the depth of the top of the channel. The main objective of this work is to characterize the reduction in uncertainty in channel model parameters and predicted reservoir performance that can be achieved by conditioning to well-test pressure data at one or more wells. Multiple conditional realizations of the geometric parameters and rock properties are generated to evaluate the uncertainty in model parameters. The ensemble of predictions of reservoir performance generated from the suite of realizations provides a Monte Carlo estimate of the uncertainty in future performance predictions. In addition, we provide some insight on how prior variances, data measurement errors, and sensitivity coefficients interact to determine the reduction in model parameters obtained by conditioning to pressure data and examine the value of active and observation well data in resolving model parameters.  相似文献   

11.
Harrat Lunayyir is one of the smaller lava fields in western Saudi Arabia that is of current interest due to a dike intrusion episode in 2009, an ongoing swarm of earthquakes and the possible hazard that pose. In addition to seismology, other geophysical data have been used to study the structure of the area, and the available aeromagnetic information is shown and discussed here. The reduced to the pole (RTP) magnetic grid and its enhancements have been used to define some of the main anomalies, and these have been correlated with the known geology, including the Red Sea coastal dike system. There are numerous linear features that are possibly related to the dikes or faulting, but within the area of the harrat, details due to the underlying structure are largely obscured by the magnetic surface lavas. Northeasterly trends in the magnetic data may indicate old zones of weakness that intersect one of the main coastal dikes at the location of the recent seismic activity and surface fissure, suggesting that this is a point of weakness resulting in the volcanism and seismicity that also appears to be largely limited to two of the NE trends. The association of the recent seismicity with a known geological and aeromagnetic feature is important in determining the seismic hazard for the region, especially if the location of future activity can be used to reduce overall uncertainty in the analysis by identifying potential fault sources. Here, the seismicity appears to lie on one of the NNW-trending coastal dikes that have been reactivated recently along a section between two NE-trending older faults.  相似文献   

12.
针对目前复杂构造三维恢复过程中地质体产生空间位置变化的不确定性,采用三维原位恢复方法,以巴楚断隆S1 构造为例,通过对比S1 构造恢复过程中所选取的标准区域与样本区域在构造变形前后的空间位置变化,分析构造变化过程中S1 构造整体模型的位置变化规律; 并据此将构造复原后的模型整体变化至初始位置,消除S1 构造因去掉石炭系顶面断距带来西南方向的位移,也消除了因去掉石炭系褶皱所带来西南方向的位移。研究表明,运用三维原位恢复技术,能够确保地质模型在构造复原前后空间位置不变,进而保证研究主体在构造恢复过程中空间位置的相对稳定,为分析构造变形带来的影响奠定空间比较基础。  相似文献   

13.
古地震学:活动断裂强震复发规律的研究   总被引:1,自引:0,他引:1  
古地震学是活动构造学、地震地质学和构造地貌学相结合的一个分支学科,它以野外工作为基础,以史前地震的发生位置、时间及震级为研究目标,其核心是古地震事件变形的地层和地貌证据.古地震学通过运用沉积地层学、地貌学和构造地质学等研究中常用的方法和手段来识别第四纪沉积中保存的史前强震的证据并对其进行准确年代测定,弥补了历史地震和仪...  相似文献   

14.
A simple flood hazard assessment based on GIS and multicriteria decision analysis was presented, and the sensitivity analysis was applied to evaluate the uncertainty of input factors. The location chosen for the study is the Kujukuri Plain, Chiba Prefecture, Japan. The model incorporates six factors: river system, elevation, depression area, ratio of impermeable area, detention ponds, and precipitation. A hazard map for the year 2004, as an example, was obtained. The method of analytic hierarchy process was applied to calculate the weighting values of each factor. The hazard map was compared with the actual flood area, and good coincidence was found between them. The relative importance and uncertainty of the six input factors and weights were evaluated by using the global sensitivity analysis, i.e., extended FAST method, and the results showed a robust behavior of the model. The flood hazard assessment method presented here is meaningful for the flood management and environment protection in the area under the similar condition as this study.  相似文献   

15.
With the recent transition to a more risk-based approach in flood management, flood risk models—being a key component in flood risk management—are becoming increasingly important. Such models combine information from four components: (1) the flood hazard (mostly inundation depth), (2) the exposure (e.g. land use), (3) the value of elements at risk and (4) the susceptibility of the elements at risk to hydrologic conditions (e.g. depth–damage curves). All these components contain, however, a certain degree of uncertainty which propagates through the calculation and accumulates in the final damage estimate. In this study, an effort has been made to assess the influence of uncertainty in these four components on the final damage estimate. Different land-use data sets and damage models have been used to represent the uncertainties in the exposure, value and susceptibility components. For the flood hazard component, inundation depth has been varied systematically to estimate the sensitivity of flood damage estimations to this component. The results indicate that, assuming the uncertainty in inundation depth is about 25 cm (about 15% of the mean inundation depth), the total uncertainty surrounding the final damage estimate in the case study area can amount to a factor 5–6. The value of elements at risk and depth–damage curves are the most important sources of uncertainty in flood damage estimates and can both introduce about a factor 2 of uncertainty in the final damage estimates. Very large uncertainties in inundation depth would be necessary to have a similar effect on the uncertainty of the final damage estimate, which seem highly unrealistic. Hence, in order to reduce the uncertainties surrounding potential flood damage estimates, these components deserve prioritisation in future flood damage research. While absolute estimates of flood damage exhibit considerable uncertainty (the above-mentioned factor 5–6), estimates for proportional changes in flood damages (defined as the change in flood damages as a percentage of a base situation) are much more robust.  相似文献   

16.
In this paper, we propose a framework for quantifying risks, including (1) the effects of forecast errors, (2) the ability to resolve critical grid features that are important to accurate site-specific forecasts, and (3) a framework that can move us toward performance-based/cost-based decisions, within an extremely fast execution time. A key element presently lacking in previous studies is the interrelationship between the effects of combined random errors and bias in numerical weather prediction (NWP) models and bias and random errors in surge models. This approach examines the number of degrees of freedom in present forecasts and develops an equation for the quantification of these types of errors within a unified system, given the number of degrees of freedom in the NWP forecasts. It is shown that the methodology can be used to provide information on the forecasts and along with the combined uncertainty due to all of the individual contributions. A potential important benefit from studies using this approach would be the ability to estimate financial and other trade-offs between higher-cost “rapid” evacuation methods and lower-cost “slower” evacuation methods. Analyses here show that uncertainty inherent in these decisions depends strongly on forecast time and geographic location. Methods based on sets of surge maxima do not capture this uncertainty and would be difficult to use for this purpose. In particular, it is shown that surge model bias can play a dominant role in distorting the forecast probabilities.  相似文献   

17.
The aim of this paper is to propose a location model of earthquake emergency service depot on the basis of hybrid multi-attribute decision-making method. The advantage of the proposed method is that practical mixed uncertainty of location decision information is considered, and the corresponding factors that affect the location of transfer stations are contained. To solve the location problem, a hybrid multi-attribute decision procedure without information transformation is developed. Besides, a novel weighting method and aggregation process is given. Finally, a numerical example is provided to show the feasibility and validity of the proposed method.  相似文献   

18.
China is prone to highly frequent earthquakes due to specific geographical location, which could cause significant losses to society and economy. The task of seismic hazard analysis is to estimate the potential level of ground motion parameters that would be produced by future earthquakes. In this paper, a novel method based on fuzzy logic techniques and probabilistic approach is proposed for seismic hazard analysis (FPSHA). In FPSHA, we employ fuzzy sets for quantification of earthquake magnitude and source-to-site distance, and fuzzy inference rules for ground motion attenuation relationships. The membership functions for earthquake magnitude and source-to-site distance are provided based on expert judgments, and the construction of fuzzy rules for peak ground acceleration relationships is also based on expert judgment. This methodology enables to include aleatory and epistemic uncertainty in the process of seismic hazard analysis. The advantage of the proposed method is in its efficiency, reliability, practicability, and precision. A case study is investigated for seismic hazard analysis of Kunming city in Yunnan Province, People’s Republic of China. The results of the proposed fuzzy logic-based model are compared to other models, which confirms the accuracy in predicting the probability of exceeding a certain level of the peak ground acceleration. Further, the results can provide a sound basis for decision making of disaster reduction and prevention in Yunnan province.  相似文献   

19.
Chamberlin (1910) was the first to quantitatively predict the shape and position of a basal detachment from detailed surface observations. His predicted detachment beneath the Appalachian Valley and Ridge fold-thrust belt of central Pennsylvania is substantially deeper and differs in geometry from the current interpretation. The modern profile by Faill and Nickelsen (1999) across the same area shows a much shallower, planar lower detachment and the presence of a duplex below the surface folds, a significant conceptual difference from the Chamberlin profile. Two assumptions prove to be critical in causing the discrepancies, the width of the segments used as the unit of analysis, and the assumption of constant bed length. The segmentation scheme led to an erroneous conjugate-fault detachment geometry. The depth discrepancy is primarily due to ignoring the layer-parallel strain. The duplex is of the coupled-roof style and not responsible for the differences, a result supported by an experimental model. We use the modern profile and the area–depth relationship to quantify the effects of uncertainty on profile geometry and estimates of orogenic shortening. Small differences in the assumptions (inference error) lead to significant differences in displacement, detachment location and layer-parallel strain. Our best area-balanced interpretation is a slightly modified version of the Faill and Nickelsen profile.  相似文献   

20.
湿地是自然界中重要的“碳汇”,其碳储量变化对全球气候变化和温室效应有重要的影响.选择地理位置独特的黑龙江兴凯湖自然保护区作为研究区,根据保护区内不同土壤类型采集表层(0~20 cm)土壤样品,利用遥感解译的保护区土地利用图、土壤储碳量和植物固碳量计算公式,核算兴凯湖自然保护区生态系统固碳服务总量,同时借鉴瑞典碳税法和中国造林成本法,估算兴凯湖保护区固碳服务功能价值为4.9亿元.结果显示,兴凯湖自然保护区湿地固碳服务功能高于全国平均水平,且高于同纬度同属东北平原的莫莫格湿地,为保护区今后的保护管理策略提供了有效的参考依据.  相似文献   

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