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1.
Pattern classification using tabu search to identify the spatial distribution of groundwater pumping 总被引:1,自引:0,他引:1
Pattern classification and Tabu Search are integrated to optimize the zonation and associated average groundwater pumping rates. A simulated problem analogous to the Choushui Creek Alluvial in Janghauh county of Taiwan is used to examine the proposed method. Three problems are tested including (1) optimizing zonation patterns with known pumping rates and number of zones, (2) optimizing pumping rates and zonation patterns with a predetermined number of zones, and (3) optimizing all pumping rates, number of zones, and zonation. The results indicate that the proposed method successfully identifies spatial patterns of groundwater pumping for all three cases. However, some initial zonations result only in local optimums. Thus, using more than one initial zonation to increase search diversification is recommended. Application to different problems such as the spatial distribution of hydraulic conductivity values and area weighting of rainfall stations, is encouraged.
Resumen El patrón de clasificación y la búsqueda tabú están integrados para optimizar la zonificación y las tasas promedio de bombeo de aguas subterráneas asociadas. Se ha utilizado un área diseñada análoga al arroyo aluvial Choushui en la provincia Janghauh en Taiwan para examinar el método propuesto. Se han probado tres problemas que incluyen (1) la zonificación únicamente con las tasas de bombeo y número de zonas dadas, (2) tasa de bombeo y zonificación con un número predeterminado de zonas, y (3) todas las tasa de bombeo, número de zonas y zonificaciones. Los resultados indican que el método propuesto identifica exitosamente los patrones espaciales de bombeo de las aguas subterráneas en los tres casos. Sin embargo, Algunas zonificaciones iniciales solamente resultan en óptimos locales. Por esta razón se recomienda utilizar más de una zonificación inicial para incrementar la diversificación de la búsqueda. Se sugiere la aplicación a problemas diferentes tales como la distribución espacial de conductividades hidraúlicas y la ponderación de áreas de estaciones de monitoreo de precipitación.
Résumé La classification des patrons et la recherche Tabu sont intégrés pour optimiser la zonation et la moyenne associée du taux de pompage de leau souterraine. Une région analogue à lalluvion du ruisseau Choushui de la région Janghauh en Taiwan a été recrée afin dexaminer la méthode proposée. Trois problèmes sont évalués, incluant loptimisation de (1) la zonation avec seulement un taux de pompage et un nombre de zones donnés, (2) le taux de pompage et la zonation avec un nombre prédéterminé de zones, et (3) tous les taux de pompage, nombre de zones et la zonation. Les résultats indiquent que la méthode proposée identifie avec succès les patrons de pompage de leau souterraine dans les trois cas. Toutefois, certaines zonations initiales résultent seulement en optimums locaux. Par conséquent, lutilisation de plus dune zonation initiale afin daugmenter la diversification de la recherche est recommandée. Lutilisation de la méthode est suggérée pour la résolution de différents problèmes tels que la distribution spatiale de la conductivité hydraulique et la pondération des stations de mesure de précipitations.相似文献
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新疆煤田火烧区特征及其勘探灭火问题的探讨 总被引:5,自引:0,他引:5
煤田火烧区的存在,给勘探、建井、开矿均带来一定的危害。本文重点论述新疆煤田火烧区的特征,煤田火烧区的危害和煤田火烧区的主要形成因素,经过各种勘探方法的对比,选用地面物探方法(磁法和自然电场法)查清了煤层火烧区的分布范围和煤层地下燃烧状态。物探成果资料经钻孔验证技术效果良好,根据煤层高温燃烧区定期观测剖面测定结果,对新疆煤田火烧区储量的损失作了科学的推算。对煤田高温燃烧区灭火方法作了简要说明,并对灭火效果提出了一定见解。对灭火工程的验收程序提出了合理化建议。 相似文献
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Natural Hazards - Arid regions are highly vulnerable to climate change and human activity, and global warming in particular has the potential to increase the arid land area. One traditional way to... 相似文献
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甘肃岗岔金矿位于秦岭造山带之碌曲-成县逆冲推覆构造带的西段北侧,是典型的构造蚀变岩型金矿床,目前储量可达中型。在矿区地质填图的基础上,采用BJKF-1型近红外矿物分析仪对矿区7号勘探线ZK07-4钻孔、8号勘探线ZK08-6钻孔及27号勘探线的ZK27-1、ZK27-3、ZK27-4钻孔岩心进行蚀变特征研究,识别出的主要蚀变矿物为伊利石、云母类、地开石、高岭石等。蚀变矿物分布及含量变化特点表明,与矿化有关的蚀变主要是绢英岩化,其中已探明矿体多位于采用近红外分析技术圈出的绢英岩化带内。此外,伊利石反射光谱特征参数计算结果表明,伊利石结晶度和Al-OH特征吸收峰形态呈现有规律的变化,即含矿段和近矿段伊利石结晶度大(SWIR-IC值5.5~5.7),Al-OH吸收峰尖锐;远矿段和无矿段伊利石结晶度小(SWIR-IC值1.3~1.5),Al-OH吸收峰平缓,显示含矿段伊利石形成温度较高。上述结果表明,矿区内绢英岩化蚀变及伊利石结晶度、Al-OH峰形是有利找矿标志,对找矿具有实际指导意义。 相似文献
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位场场源边界识别是位场数据分析解释中的重点内容之一。相邻异常源由于场的叠加而难以区分,尤其是对于叠加异常中不同深度的场源边界的识别。倾斜角法是位场数据处理中常用的边界增强方法之一,能有效突出低振幅、短波长的异常特征。本文基于倾斜角法定义了新的位场边界探测方法,该方法利用倾斜角方程中位场二阶垂直导数与垂向导数水平导数之比进行计算,能有效区分相邻异常源产生的叠加异常,突出叠加异常中不同深度场源的边界特征。通过综合模型和实测数据,并与现有的基于导数的位场边界探测方法进行比较,评价了该方法的应用效果。结果表明,该方法对场源深度的变化不太敏感,它可以更准确地确定场源边界,区分相邻异常源的叠加异常,尤其对密集型组合地质构造的识别有较好的效果,即使是在场源埋深较大情况下,也能突出叠加异常中不太明显的微弱变化的线性异常特征,以及弱异常源的形态特征,可为精细研究局部地质构造提供技术支持。 相似文献
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Infrared (IR) spectra of minerals can be recorded by photothermal beam deflection spectroscopy with minimal sample preparation and even with no sample preparation at all. A modulated IR beam is focussed onto the sample, radiation selectively absorbed by the solid warms the solid and the air over it and brings about a refractive index gradient in the air, so that a laser beam grazing the solid's surface is deflected. Measurements of the deflections result in the IR photothermal absorption spectrum. Sample preparation steps can be avoided entirely, i.e., selected areas on the surface of a large specimed can be examined directly, provided that the laser probe beam can pass over the sample area. A minimal sample preparation, consisting of lightly grinding the sample by hand, increases sensitivity and avoids spectral reflection effects. Examples of application of the technique to carbonate and lead minerals are shown. 相似文献
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Heavy metals are toxic elements that have hazardous effect on the environment. They cause soil pollution as a result of their toxicity, potential reactivity, and mobility in soils. There are so many methods for the measurement of heavy metal concentrations in soils and aquatic systems. The traditional methods used for detecting heavy metal distribution in soil involve laboratory analysis and raster sampling. Both of them are expensive and time-consuming for large areas. Remote sensing techniques are used for obtaining the earth’s surface information, and these techniques have been used in the investigations of heavy metal distributions in preliminary analysis of soils as a rapid method. Today, near-infrared reflectance spectroscopy (NIRS) of soil characteristics has been of interest as a significant object. The present investigation is focused on the detection of heavy metals in contaminated soils by the application of reflectance spectroscopy in the spectral range of 350 to 2500 nm. This study also discusses the circumstances of the applied current methods for the detection and estimation of arsenic (As), cadmium (Cd), nickel (Ni), and lead (Pb) in contaminated agricultural soils. In the first part of laboratory spectroscopy, estimations were done using heavy metal reflectance spectroscopy and partial least square regression (PLSR) approaches, while in the second part, the heavy metal estimations were done using soil organic carbon reflectance spectroscopy through the PLSR approaches. Similar to the tasks above, estimations of As, Cd, Ni, and Pb by using Landsat 8 images were done in the forms of direct and indirect methods and the distribution of heavy metals in the study area was determined. Finally, the results obtained using direct and indirect methods were compared with the wet chemical measurements of heavy metals and organic carbon. It was found that although the direct detection of heavy metals using the images of Landsat 8 produced more accurate results than the indirect detections, the results obtained from laboratory spectroscopy corresponded more with the results from atomic adsorption spectroscopy. On the other hand, based on the fact that the soil has a complex content, the use of nonlinear methods, such as artificial neural networks in predicting soil heavy metal contents, could be regarded as a trusted method. 相似文献
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After the 1999 Chi-Chi earthquake, the Taiwanese government immediately issued new guidelines prohibiting the construction
of structures for human occupancy within the Chelungpu fault zone. However, these guidelines were not based upon an in-depth
hazard analysis of the near-fault regions. The positions of more than 80% of the 2,492 victims of the Chi-Chi earthquake were
found by our research team. A Victim Attribute Database has been compiled that includes the GPS coordinates of the positioned
victims as well as other attribute data associated with the victims. The human-fatality rates in the near-fault regions have
been analyzed with regard to distances from the Chelungpu fault, the hanging-wall and footwall areas, as well as building
type. The severity at the human-fatality rates in the near-fault regions is inversely proportional to distances from the causative
fault, i.e., the closer the distance, the higher the human-fatality rate observed. The human-fatality rate for victims who
lived in closer proximity to the hanging-wall areas is also significantly higher than those who lived in closer proximity
to the footwall areas, especially in areas on either side of the fault and within 1,000 m of the fault surface trace. In terms
of different building types, factors that include the capacity of the buildings to resistant strong shaking and the level
of strong ground-motion greatly affected the human-fatality rates in the hanging-wall and footwall areas. Therefore simply
prohibiting the construction of buildings within the active fault zone would be an insufficient method of reducing the number
of potential victims; a nationwide effort should be undertaken to upgrade the capacity of buildings to resist strong shaking. 相似文献
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我国有多条油气管道位于多年冻土地区,工程问题层出不穷。因输送介质处于正温状态,其所释放热量对管道周围冻土冻融过程有极大影响。为阐明正温管道对多年冻土温度场及冻融特征的影响,基于西部某多年冻土区正温输气管道现场实验,对管道地基温度场进行了为期1年的现场实测。数据分析表明,多年冻土天然上限为1.5~2.0 m;土体融化期及冻结期分别为6-10月、11-次年5月;监测段多年冻土热量收支基本平衡,属于不稳定冻土,在外界热扰动下极易退化;正温输气管道的存在引起了多年冻土的退化且对其温度场有很大影响,水平方向影响范围约1.5 m,管下最大融深可达7.0 m。同时指出了针对处于临界状态的多年冻土,在基于对其全面、深入了解的基础上,越早考虑相关工程建设带来的热扰动对多年冻土的不利影响,则处置难度越低且损失越小。 相似文献
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Engineering geophysics provides valuable and continuous information for the planning and execution of tunnel construction
projects. For geotechnical purposes special high-resolution geophysical methods have been developed during the last decades.
The importance of applying geophysical methods in addition to usually used geological and geotechnical exploration techniques
is increasing. The main goal is to achieve an accurate and continuous model of the subsurface in a relative short period of
operation time. The routine application of engineering geophysical methods will increase in the coming years. Due to the high
acceptance of engineering geophysics at construction sites, much wider application of geophysical investigations is expected.
The combination of different methods—geophysics, geology, and geotechnics as well as the so-called joint interpretation techniques—will
be of essential importance. Engineering geophysics will play an important role during the three phases: geological investigation,
tunnel planning, and execution of tunnel construction. If hazards are well known in advance of a tunnel project the safety
of workers will essentially be increased and geological risks will be minimized by means of successful and interdisciplinary
cooperation. 相似文献
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Michael L. Turnbull 《Journal of Earth System Science》2008,117(2):879-895
An alternative seismic shaking vulnerability survey method to computational intensive theoretical modelling of site response to earthquake, and time consuming test versus reference site horizontal ratio methods, is described. The methodology is suitable for small to large scale engineering investigations. Relative seismic shaking vulnerability microzonation using an adaptation of the Nakamura horizontal to vertical spectral ratio method provides many advantages over alternative methods including: low cost; rapid field phase (100 km2 can easily be covered by a single operator in 5 days); low and flexible instrumentation requirements (a single seismometer and data logger of almost any type is required); field data can be collected at any time during the day or night (the results are insensitive to ambient social noise); no basement rock reference site is required (thus eliminating trigger synchronisation between reference and multiple test site seismographs); rapid software aided analysis; insensitivity to ground-shaking resonance peaks; ability to compare results obtained from non-contiguous survey fields. The methodology is described in detail, and a practical case study is provided, including mapped results. The resulting microzonation maps indicate the relative seismic shaking vulnerability for built structures of different height categories within adjacent zones, with a resolution of approximately 1 km. 相似文献
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选择天山和祁连山区为典型区,利用台站降水数据验证以上两区多卫星降水数据(TRMM)精度的基础上,借助TRMM数据分析了所选山区年降水梯度效应,并探讨了天山及祁连山最大降水高度带.结果表明,多卫星降水数据在天山和祁连山区精度较高,天山及祁连山年降水量都明显受到海拔影响,降水随海拔升高而增加,但天山降水与海拔正相关关系最好,南、北和西坡相关系数分别为0.90、0.81和0.58,多年平均降水直减率分别为11.0mm/100 m、6.3 mm/100 m、7.4 mm/100 m,最大降水高度带则分别位于海拔2 200~3 500 m和3 200~3 700 m和3 000m左右;祁连山东、中、西段降水随海拔有增加趋势,但降水梯度效应在祁连山东段明显高于祁连山中西段地区,梯度效应由东向西呈现递减趋势,其最大降水带主要分布在东段4 000~4 500 m的高山带. 相似文献
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查明含烃区与不含烃区的频谱差异是利用频谱属性开展地震烃类检测工作的重要前提。为了直观地确定出含烃区与不含烃区的频谱差异,提出基于频谱差异的烃类检测方法,结合实际油气试采数据和研究需要,将已知井分为含烃井与不含烃井,通过比较分类对象射孔段的瞬时振幅谱(点谱)来找出含烃相关的频谱差异,并利用多种频谱属性交会的方式得到地震含烃区。本文通过目的层盒1段下伏煤层有无的正演模型确定了最大波谷振幅属性为预测储层信息的有利属性,但更深入分析认为频谱差异属性比常规的最大波谷属性更能表征含烃与不含烃的差异。通过设置属性门槛值的方式来量化含烃区与不含烃区在频谱属性上的差异,并将10 Hz单频振幅、25 Hz积分振幅、低频衰减梯度、高频衰减梯度等4种含烃门槛值内的频谱属性进行交会,继而确定出潜在的含烃区,通过水平井验证检测结果,表明该方法具有一定的有效性。 相似文献
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I. M. Mramorova 《Moscow University Geology Bulletin》2012,67(2):138-142
This paper is devoted to the comparison of several results that were processed using three methods, viz., the common depth point method, multifocusing, and parametrical scanning technology. The problem of the correctness of using these methods for given parameters is analyzed. 相似文献
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I. V. Gosachinskij V. K. Dubrovich S. R. Zhelenkov G. N. Il’in V. A. Prozorov 《Astronomy Reports》2002,46(7):543-550
We report the results of a search for spatial and spectral fluctuations of the cosmic microwave background in the region of the North celestial pole carried out at 6.2 cm using the RATAN-600 radio telescope in 1999–2000. The spatial spectrum is flat and has no features exceeding ΔT/T =10?3 in a ~1 MHz frequency band for spatial periods from 0.5′ to 16′. If this estimate is adopted as an upper limit for emission associated with the first rotational transition of primordial LiH at z=90.7, we obtain an upper limit for the LiH abundance of about 3×10?14 for protocluster masses of about 1013 M ⊙. 相似文献
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Recent studies in the United States and other Pacific Rim countries have identified a new form of ethnic minority group clustering
within the residential mosaic—ethnoburbs. These are suburban in location, occupied by relatively high-income, predominantly
Asian, immigrants, and low density in their nature: many migrants move directly to those suburbs rather than the inter-generational
outward migration from central city clusters typical of other migrant streams. Although ethnoburb residents tend to cluster
in particular segments of the built-up area they do not to form large percentages of the population there. As yet, no methodology
has been developed to identify these clusters, as a prelude to identifying their characteristics. This paper offers such a
procedure, based on local statistical analysis. It is applied to six Asian groups in Auckland, New Zealand. 相似文献
20.
Integrated use of GIS and remote sensing for monitoring landslides in transportation pavements: the case study of Paphos area in Cyprus 总被引:1,自引:0,他引:1
D. D. Alexakis A. Agapiou M. Tzouvaras K. Themistocleous K. Neocleous S. Michaelides D. G. Hadjimitsis 《Natural Hazards》2014,72(1):119-141
This study considers the impact of landslides on transportation pavements in rural road network of Cyprus using remote sensing and geographical information system (GIS) techniques. Landslides are considered to be one of the most extreme natural hazards worldwide, causing both human losses and severe damages to the transportation network. Risk assessment for monitoring a road network is based on the combination of the probability of landslides occurrence and the extent and severity of the resultant consequences should the disasters (landslides) occur. Factors that can trigger landslide episodes include proximity to active faults, geological formations, fracture zones, degree and high curvature of slopes, water conditions, etc. In this study, the reliability and vulnerability of a rural network are examined. Initially, landslide locations were identified from the interpretation of satellite images. Different geomorphological factors such as aspect, slope, distance from the watershed, lithology, distance from lineaments, topographic curvature, land use and vegetation regime derived from satellite images were selected and incorporated in GIS environment in order to develop a decision support and continuous landslide monitoring system of the area. These parameters were then used in the final landslide hazard assessment model based on the analytic hierarchy process method. The results indicated good correlation between classified high-hazard areas and field-confirmed slope failures. The CA Markov model was also used to predict the landslide hazard zonation map for 2020 and the possible future hazards for transportation pavements. The proposed methodology can be used for areas with similar physiographic conditions all over the Eastern Mediterranean region. 相似文献