RGIS软件2.5D人机交互反演的数据处理流程

2.5D人机交互反演是目前在重力资料解释中比较成熟的方法。本文以RIGS软件处理某工区重力数据为例,简要介绍下反演前的数据处理流程。提取剩余布格异常、网格数据提取剖面等。     

2.5D反演在辽宁某磁铁矿区中的应用效果

本文主要介绍对磁测资料的常规处理和2.5D人机交互反演解释,确定测区内磁铁矿埋深、空间形态。经钻探验证,表明了2.5D人机交互反演的有效性。     

可控源音频大地电磁法在寻找隐伏铝土矿中的应用

简单介绍了可控源音频大地电磁法(CSAMT)的工作原理及工作区的地质和地球物理特征,重点介绍了CSAMT法在荥阳地区寻找隐伏铝土矿中的应用。通过成都理工大学编写的MTSoft2D软件包的1D OCCAM反演结果为初始模型,进行多次2D非线性共轭梯度(NLCG)迭代,很好的压制了由于地表不均匀体造成的深层奥灰岩面失真的现象,较为准确地定位出奥陶系灰岩界面的起伏特征及埋藏深度,结合工作区铝土矿的成矿规律,对区内的铝土矿的空间赋存做出了较为准确的判断。     

波阻抗反演技术在溱潼凹陷南部储层预测中的应用

由于各地区的地质沉积环境不同,储层所反映的地球物理特征有较大的差异,通过对井资料的统计分析,寻找符合研究区的储层地球物理特征,为制定更加合理的地震反演提供依据,地震反演主要包括:层位标定及层位解释、子波的提取、模型建立、及主要参数的选取等。通过波阻抗反演技术的研究,能够有效预测优势储层的位置,为下一步的勘探开发提供参考基础。     

常规激电测深反演效果对比研究

本文介绍了对常规激电测深数据采用多个软件反演的效果对比,结合地质情况,选取较为合理的断面,从而为实际生产提供更准确的地球物理依据。     

地球物理不规则分布数据空间网格化法在矿山检测中的应用

在地球物理研究工作中,数据处理和数据解释是其中的关键问题,而不规则分布数据又是地球物理数据中的基础问题,采用空间网格化法能够从基础上保证地球物理数据处理工作的准确性。本文首先建叙述集中常见的空间网格化法分析,并在矿山检测中的到应用。     

黑龙江三道湾子岩金矿区岩矿石物性研究与应用

岩矿石的物性差异是引起各种地球物理异常的直接原因。物性差异也是进行地球物理勘查、异常定性解释和定量反演的必要条件。本文对三道湾子岩金矿区的岩矿石进行了系统的物性测定、统计分析和研究应用,研究成果为地球物理勘查提供了可靠的施工依据,为矿产勘查提供了间接找矿依据。根据不同的地质需求,有针对性的在找矿靶区设计适用的地球物理勘探方法,结合物性研究成果,给出合理的地质解释和精确的反演结果。     

激电中梯在内蒙古雅干地区的应用

介绍了1:1万激电中梯电法勘探在内蒙古额济纳旗雅干地区多金属勘察中的具体应用,结合该地区已有的地质、地球物理、地球化学资料在两个找矿靶区(Ⅰ区、Ⅱ区)布设了电法测量,对野外测量数据处理解释,圈定了两个异常区,并对异常进行了定性解释,了解了测区视电阻率、视极化率等电性特征,为下一步工作提供了一定的地球物理依据。     

黔西南贞丰背斜卡林型金矿的综合地球物理勘查—钻孔岩芯物性研究

在黔西南贞丰背斜卡林型金矿研究区开展综合地球物理勘查项目的同时,为了数据反演和地质解释的需要,分别利用3522-50LCR电性测试仪、SM30手持磁化率仪、2G-760U-Channel岩石超导磁力仪和高精度物理天平对黔西南贞丰背斜卡林型金矿钻孔岩芯电阻率、磁化率、剩余磁化强度和密度进行了精细测量,得到了不同岩性岩石的各项物性参数,明确了卡林型金矿围岩的物性特征。在测量电阻率时特别注意测量样品2个方向的电阻率,发现了沉积岩在电性上的各向异性特征。数据显示该地区主要岩性岩石在不同物理性质上有不同差异。研究结果对于在该地区和地质条件相似的邻近地区开展卡林型金矿的地球物理勘探提供了方法选择的参考和测量数据反演必不可少的依据。     

微动方法在矿山采空区探测中的应用

在长期的矿山开采过程中,形成了大量采空区,时刻威胁着矿山的正常生产及人员的生命安全,采空区勘查的重要性越来越高。近年来,微动作为一种较新的地球物理手段,在采空区勘查中取得了很好的应用效果。本文以湖北大冶某矿山采空区勘查为例,介绍了微动方法的原理、野外数据采集、数据处理和反演,对成果分析后认为,微动方法能很好的反映采空区形态、大小、埋深等空间分布特征,可为矿山采空区的调查和治理提供有效的技术支撑。     

FLAC和神经网络在隧道位移反分析中的应用

应用三维有限差分程序FLAC^3D和BP神经网络对隧道位移进行分析,使用正交实验和FLAC^3D正演结果作为样本,用神经网络建立围岩位移与反演参数的映射关系．反演得出了围岩的弹性模量和初始地应力测压系数,并使用FLAC^3D正算验证反演参数的精度．结果表明：可搜索得出反演参数的最优解,实现在隧道围岩中的位移反分析．可将反演结果用于隧道的设计,反演精度满足工程要求．     

Two-Dimensional Simulation of Subcritical Flow at a Combining Junction: Luxury or Necessity?

Classically, in open-channel networks, the flow is numerically approximated by the one-dimensional Saint Venant equations coupled with a junction model. In this study, a comparison between the one-dimensional (1D) and two-dimensional (2D) numerical simulations of subcritical flow in open-channel networks is presented and completely described allowing for a full comprehension of the modeling of water flow. For the 1D, the mathematical model used is the 1D Saint Venant equations to find the solution in branches. For junction, various models based on momentum or energy conservation have been developed to relate the flow variables at the junction. These models are of empirical nature due to certain parameters given by experimental results and moreover they often present a reduced field of validity. In contrast, for the 2D simulation, the junction is discretized into triangular cells and we simply apply the 2D Saint Venant equations, which are solved by a second-order finite-volume method. In order to give an answer to the question of luxury or necessity of the 2D approach, the 1D and 2D numerical results for steady flow are compared to existing experimental data.     

Comparison of HYDRUS-2D Simulations of Drip Irrigation with Experimental Observations

Realizing the full potential of drip irrigation technology requires optimizing the operational parameters that are available to irrigators, such as the frequency, rate, and duration of water application and the placement of drip tubing. Numerical simulation is a fast and inexpensive approach to studying optimal management practices. Unfortunately, little work has been done to investigate the accuracy of numerical simulations, leading some to question the usefulness of simulation as a research and design tool. In this study, we compare HYDRUS-2D simulations of drip irrigation with experimental data. A Hanford sandy loam soil was irrigated using thin-walled drip tubing installed at a depth of 6 cm. Three trials (20, 40, and 60 L?m?1 applied water) were carried out. At the end of each irrigation and approximately 24 h later, the water content distribution in the soil was determined by gravimetric sampling. The HYDRUS-2D predictions of the water content distribution are found to be in very good agreement with the data. The results support the use of HYDRUS-2D as a tool for investigating and designing drip irrigation management practices.     

A visual environment for the manipulation and integration of JAVA beans

Drosophila ananassae, although a cosmopolitan and domestic species, is largely circumtropical in distribution. It occupies unique status in the whole of genus Drosophila due to certain peculiarities in its genetical behaviour. The most unusual feature of this species is spontaneous male recombination in appreciable frequency. This species is of common occurrence in India. Population genetics of inversion polymorphism has been extensively studied in Indian D. ananassae in our laboratory. The main findings are: (i) Three cosmopolitan inversions namely AL in 2L, DE in 3L and ET in 3R are of frequent occurrence in Indian populations and have become coextensive with the species. (ii) Quantitative data on the frequency of three cosmopolitan inversions in 29 natural populations of D. ananassae suggest that there is a considerable degree of genetic divergence at the level of inversion polymorphism. In general, the populations from south India show more differentiation than those from the north. (iii) These three cosmopolitan inversions exhibit heterosis. Interracial hybridization does not lead to breakdown of heterosis, which suggests that evidence for coadaptation is lacking in geographic populations of D. ananassae. Heterosis appears to be simple luxuriance rather than populational heterosis (coadaptation). (iv) Data on intra- and interchromosomal associations in natural and laboratory populations of D. ananassae show that interchromosomal associations occur randomly indicating no interchromosomal interactions but two inversions of the third chromosome often show strong linkage disequilibria in laboratory populations which is due to epistatic interaction and suppression of crossing over. The role of genetic drift causing linkage disequilibria in isofemale strains of D. ananassae has also been suggested. (v) Mating ability of homo- and hetero-karyotypes due to subterminal (2L) inversion derived from natural populations of D. ananassae in which the frequency of different chromosome arrangements were known, was tested and the results indicate that the chromosome occurring in high frequency is associated with higher mating activity in all the populations analysed and heterokaryotypic males are superior in mating propensity to the corresponding homokaryotypes, indicating the existence of heterosis associated with the AL inversion with respect to male mating activity. Thus inversion polymorphism in D. ananassae may have a partial behavioural basis as has been demonstrated in other species of Drosophila.     

The relationship between adults’ conceptual understanding of inversion and associativity.

Children’s understanding of the mathematical concepts of inversion and associativity are positively related, as measured by the use of conceptually based shortcut strategies on 3-term inversion problems (i.e., a + b – b, d × e ÷ e) and associativity problems (i.e., a + b – c, d × e ÷ f; Robinson & Dubé, 2009; Robinson & Ninowski, 2003). Individuals who use the inversion shortcut (e.g., 3) are more likely to use the associativity strategy (e.g., 3 × 12 ÷ 4. 12 ÷ 4 = 3, 3 × 3 = 9), which is almost never used by an individual who does not also use the inversion shortcut (Robinson & Dubé, 2009). One possible reason for this relationship is that directing attention to the right-most operation during problem solving may be required to prime the conceptually based shortcut strategies for both problem types. This study investigated the relationship between adults’ understanding of inversion and associativity. Adults (N = 42) solved inversion and associativity problems in 1 of 2 conditions. The participants were either presented with the left-most operation and then the whole problem or presented with the right-most operation and then the whole problem. A positive relationship between the use of the conceptually based strategies was found, and it was strikingly similar to the relationship found in childhood. There was evidence that the presentation of the right-most operation first primed the inversion shortcut. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An improved method for evaluating the seasonal variability of total suspended sediment flux field in the Yellow and East China Seas

The suspended sediment flux field in the Yellow and East China Seas (YECS) displays its seasonal variability. A new method is introduced in this paper to obtain the flux field via retrieval of ocean color remote sensing data, statistical analysis of historical suspended sediment concentration data, and numerical simulation of three-dimensional (3D) flow velocity. The components of the sediment flux field include (i) surface suspended sediment concentration inverted from ocean color remote sensing data; (ii) vertical distribution of suspended sediment concentration obtained by statistical analysis ofhistorical observation data; and (iii) 3D flow field modeled by a numerical simulation. With the improved method, the 3D suspended sediment flux field in the YECS has been illustrated. By comparison with the suspended sediment flux field solely based on the numerical simulation of a suspended sediment transport model, the suspended sediment flux field obtained by the improved method is found to be more reliable. The 3D suspended sediment flux field from ocean colour remote sensing and in situ observation are more closer to the reality. Furthermore, by quantitatively analyzing the newly obtained suspended sediment flux field, the quantity of sediment erosion and deposition within the different regions can be evaluated. The sediment exchange between the Yellow Sea and the East China Sea can be evident. The mechanism of suspended sediment transport in the YECS can be better understood. In particular, it is suggested that the long-term transport of suspended sediment is controlled mainly by the circulation pattern, especially the current in winter.     

Investigation on the Suitability of Two-Dimensional Depth-Averaged Models for Bend-Flow Simulation

A numerical experiment is carried out to study the suitability of two-dimensional (2D) depth-averaged modeling for bend-flow simulation, in which the geometry of the studied channel is rectangular. Two commonly used 2D depth-averaged models for bend-flow simulation are considered in this study of which the bend-flow model includes the dispersion stress terms by incorporating the assumption of secondary-current velocity profile, and the conventional model neglects the dispersion stress terms. The maximum relative discrepancy of the longitudinal velocity, obtained from the comparison of these two models, is used as a criterion to judge their applicability for bend-flow simulation. The analysis of simulation results indicated that the maximum relative difference in longitudinal velocity is mainly related to the relative strength of the secondary current and the relative length of the channel. Empirical relations between the maximum relative difference in the longitudinal velocity, the relative strength of the secondary current, and the relative length of the channel for both the channel-bend region and the straight region following the bend have been established. The proposed relations provide a guideline for model users to determine the proper approach to simulate the bend-flow problem by either using the conventional model or the bend-flow model. Experimental data have been adopted herein to demonstrate the applicability and to verify the accuracy of the proposed relations.     

Experience from Two Resistivity Inversion Techniques Applied in Three Cases of Geotechnical Site Investigation

The combination of in situ geotechnical testing and continuously measured geophysical data can be a powerful tool in geotechnical site investigation. In two cases from Sweden and one case from Denmark electric resistivity surveys are used successfully in geotechnical site investigations. The main contribution of resistivity results is the possibility to interpret continuous geological models. An improved methodology combines two-dimensional (2D) smooth inversion and 2D laterally constrained inversion (2D-LCI) to significantly increase interpretability. The 2D smooth inversion has high horizontal resolution and 2D-LCI high vertical resolution. The possibility to add a priori information from, for example, drill log data to constrain the 2D-LCI increases the confidence in the inverted model and limits ambiguity. In a site investigation for a railway trench in southern Sweden a geotechnical data set is used as a priori data to increase the reliability of the inversion of the resistivity data. From this combined survey a complex Quaternary geology is described in detail. A slope stability study from south of Stockholm, Sweden, employed resistivity data together with refraction seismic and geotechnical drill log data. The result gives necessary geometrical information for the important geological units, for example for stability calculations. Both these surveys were performed with a multielectrode system. In the third case a pulled array resistivity survey was used to map the uppermost 15–20?m to estimate the distribution of the geological formations for freeway construction in Denmark. The result enables a more accurate estimate of the total freeway construction costs.     

Energy Dissipation in Transient Gaseous Cavitation

The aim of the paper is to examine nonfriction energy dissipation in transient cavitating flows and to verify whether they can be attributed to thermic exchange between gas bubbles and the surrounding liquid or to gas release and solution process. A two-dimensional (2D) numerical model for liquid flow with a small amount of free gas is proposed. The results of the numerical runs are compared with experimental data of pressure head oscillations in transient cavitating flow. Both thermic exchange and gas release can explain some of the dissipation if a relaxation process is assumed. However, the 2D model, including the thermodynamics of the gaseous phase, does not seem to fully explain the observed dissipation. The 2D model with gas release allows for a good simulation of the experimental data after a suitable calibration of the model parameters.     

It's all in your head: Why is the body inversion effect abolished for headless bodies?

It has been recently argued that human bodies are processed by a specialized processing mechanism. Central evidence was that body inversion reduces recognition abilities (body inversion effect; BIE) as much as it does for faces, but more than for other objects. Here we showed that the BIE is markedly reduced for headless bodies and examined the reason for this unexpected finding. Two alternative hypotheses were examined. Either the BIE is reduced for any type of incomplete body, or the head plays a special role in discrimination of body posture. Results show that omission of other body parts (leg or arms) did not influence the magnitude of the BIE relative to complete bodies. Analogous manipulations with faces did not influence the magnitude of the face inversion effect. Importantly, similar to effects we found for headless bodies, discrimination abilities for upright bodies and the BIE were markedly reduced for complete bodies that did not differ in head posture. We conclude that intact discrimination of body posture relies heavily on the head position. Our findings also imply that the BIE and the face inversion effect may be generated by different mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)