999 resultados para D-SEPARABLE


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In the petroleum exploration industry, it is very important to simulate the evolvement of wave field beneath our earth in the aspects of time and space quickly and effectively. Because of the huge data size in petroleum exploration and also the strict requirement of time limit in the actual process of production, simplification of models and approximation of algorithm are necessary. At the same time, every fine improvement to algorithm has its great practical significance and use value. Based on the reasons above, this dissertation researches the separable approximation methods of space-wave number domain for One-way Wave Operator and gets the conclusions as follow: 1. It is insufficient to value One-way Wave Operator purely from the mathematical modulus and phase error, while, holding some specific structural character of operator should be more important. Because, the evaluation criterion of One-way Wave Operator’s imaging ability is quite complicate and obscured, which is similar to the evaluation of an artwork. 2. We can not search for a best or most effective One-way Wave Operator approximation solution for all. However, to different speed model and precision requirement the best approximation solution does exist which is maybe also a compromise, because it is very beneficial to One-way Wave Operator to take full advantage of speed model’s pre-tested information.

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In exploration seismology, the geologic target of oil and gas reservoir in complex medium request the high accuracy image of the structure and lithology of the medium. So the study of the prestack image and the elastic inversion of seismic wave in the complex medium come to the leading edge. The seismic response measured at the surface carries two fundamental pieces of information: the propagation effects of the medium and the reflections from the different layer boundaries in the medium. The propagation represent the low-wavenumber component of the medium, it is so-called the trend or macro layering, whereas the reflections represent the high-wavenumber component of the medium, it is called the detailed or fine layering. The result of migration velocity analysis is the resolution of the low-wavenumber component of the medium, but the prestack elastic inversion provided the resolution of the high-wavvenumber component the medium. In the dissertation, the two aspects about the migration velocity estimation and the elastic inversion have been studied.Firstly, any migration velocity analysis methods must include two basic elements: the criterion that tell us how to know whether the model parameters are correct and the updating that tell us how to update the model parameters when they are incorrect, which are effected on the properties and efficiency of the velocity estimation method. In the dissertation, a migration velocity analysis method based on the CFP technology has been presented in which the strategy of the top-down layer stripping approach are adapted to avoid the difficult of the selecting reduce .The proposed method has a advantage that the travel time errors obtained from the DTS panel are defined directly in time which is the difference with the method based on common image gather in which the residual curvature measured in depth should be converted to travel time errors.In the proposed migration velocity analysis method, the four aspects have been improved as follow:? The new parameterization of velocity model is provided in which the boundaries of layers are interpolated with the cubic spline of the control location and the velocity with a layer may change along with lateral position but the value is calculated as a segmented linear function of the velocity of the lateral control points. The proposed parameterization is suitable to updating procedure.? The analytical formulas to represent the travel time errors and the model parameters updates in the t-p domain are derived under local lateral homogeneous. The velocity estimations are iteratively computed as parametric inversion. The zero differential time shift in the DTS panel for each layer show the convergence of the velocity estimation.? The method of building initial model using the priori information is provided to improve the efficiency of velocity analysis. In the proposed method, Picking interesting events in the stacked section to define the boundaries of the layers and the results of conventional velocity analysis are used to define the velocity value of the layers? An interactive integrate software environment with the migration velocity analysis and prestack migration is built.The proposed method is firstly used to the synthetic data. The results of velocity estimation show both properties and efficiency of the velocity estimation are very good.The proposed method is also used to the field data which is the marine data set. In this example, the prestack and poststack depth migration of the data are completed using the different velocity models built with different method. The comparison between them shows that the model from the proposed method is better and improves obviously the quality of migration.In terms of the theoretical method of expressing a multi-variable function by products of single-variable functions which is suggested by Song Jian (2001), the separable expression of one-way wave operator has been studied. A optimization approximation with separable expression of the one-way wave operator is presented which easily deal with the lateral change of velocity in space and wave number domain respectively and has good approach accuracy. A new prestack depth migration algorithm based on the optimization approximation separable expression is developed and used to testing the results of velocity estimation.Secondly, according to the theory of the seismic wave reflection and transmission, the change of the amplitude via the incident angle is related to the elasticity of medium in the subsurface two-side. In the conventional inversion with poststack datum, only the information of the reflection operator at the zero incident angles can be used. If the more robust resolutions are requested, the amplitudes of all incident angles should be used.A natural separable expression of the reflection/transmission operator is represented, which is the sum of the products of two group functions. One group function vary with phase space whereas other group function is related to elastic parameters of the medium and geological structure.By employing the natural separable expression of the reflection/transmission operator, the method of seismic wave modeling with the one-way wave equation is developed to model the primary reflected waves, it is adapt to a certain extent heterogeneous media and confirms the accuracy of AVA of the reflections when the incident angle is less than 45'. The computational efficiency of the scheme is greatly high.The natural separable expression of the reflection/transmission operator is also used to construct prestack elastic inversion algorithm. Being different from the AVO analysis and inversion in which the angle gathers formed during the prstack migration are used, the proposed algorithm construct a linear equations during the prestack migration by the separable expression of the reflection/transmission operator. The unknowns of the linear equations are related to the elasticity of the medium, so the resolutions of them provided the elastic information of the medium.The proposed method of inversion is the same as AVO inversion in , the difference between them is only the method processing the amplitude via the incident angle and computational domain.

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This paper gives a brief review of R&D researches for light olefin synthesis directly and indirectly from synthesis gas in the Dalian Institute of Chemical Physics (DICP). The first pilot plant test was on methanol to olefin (MTO) reaction and was finished in 1993, which was based on ZSM-5-type catalyst and fixed bed reaction. In the meantime, a new indirect method designated as SDTO (syngas via dimethylether to olefin) was proposed. In this process, metal-acid bifunctional catalyst was applied for synthesis gas to dimethylether(DME) reaction, and modified SAPO-34 catalyst that was synthesized by a new low-cost method with optimal crystal size was used to convert DME to light olefin on a fluidized bed reactor. The pilot plant test on SDTO was performed and finished in 1995. Evaluation of the pilot plant data showed that 190-200 g of DME were yielded by single-pass for each standard cubic meter of synthesis gas. For the second reaction, 1.880 tons of DME or 2.615 tons of methanol produced 1 ton of light olefins, which constitutes of 0.533 ton of ethylene, 0.349 ton of propylene and 0.118 ton of butene. DICP also paid some attention on direct conversion of synthesis gas to light olefins. A semi-pilot plant test (catalyst 1.8 1) was finished in 1995 with a CO conversion > 70% and a C(2)(=)-C(4)(=) olefin selectivity 71-74% in 1000 h. (C) 2000 Published by Elsevier Science B.V. All rights reserved.

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D型人格(指经历消极情感和社交压抑的综合行为模式)作为冠心病的心理危险因素,得到了广泛的关注。本研究在中国人群中首次探索D型人格与冠心病的关系。作者建构了心理、行为、生理、医学相结合的综合研究框架,采用问卷调查法、临床实验法以及访谈法,考察D型人格对冠心病患者身心健康的影响,以及可能的行为和生理机制。结果表明: 1.D型人格量表中文版具有良好的信度和效度。根据消极情感≧10且社交压抑≧10的划分标准,D型人格在我国冠心病人群和健康人群中的分布比例均为31%。 2.A型人格与D型人格的共同点在于消极情感,区别在于D型人格具有特殊的社交压抑结构。我国冠心病患者中A型人格比例(58%)高于健康人群(43%)。 3.A型人格与冠心病的病情(即冠状动脉狭窄程度)、患者的自评身心健康均无关。D型人格与冠心病的病情无关,但D型人格能够独立地预测自评身心健康的下降,并且不依赖于疾病状况(患病或健康)。 4.D型人格患者在应对疾病的过程中,更多地采用屈服,更少地采用面对。疾病应对方式对D型人格与患者自评身心健康的关系起中介作用。 5.在冠状动脉造影的应激条件下,冠心病患者的D型人格总分与应激下心血管反应无关,但男性患者的消极情感、社交压抑能够预测应激下舒张压反应。 此外,本研究的结果具有重要的临床价值,比如采用D型人格量表中文版鉴别高危人群以提高他们的身心健康水平,在进行D型人格干预时要关注行为方式,在对冠心病进行预防和治疗时要注意心理生理反应的性别差异等。

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Whether facial identity and facial expression was processed independently has long been a controversy. Studies at levels of experimental, neuropsychological, functional imaging and cell-recording all failed to consistently support either independent or interdependent processing. Present study proposed that familiarity and discriminability of facial identity and expression was important variable in mediating the relation between facial identity and facial expression recognition. Effects of familiarity on recognition of facial identity and expression had been examined (e.g. Ganel & Goshen-Gottstein, 2004) but the role of the discriminability in recognition of facial identity and expression has not yet been carefully examined. To examine the role of discriminability of facial identity and expression, 8 experiments were conducted with Garner’s speeded classification task in recognition of identity and expression of unfamiliar faces. The discriminability of facial identity and expression was manipulated, and the measurements of Garner interference and facilitation indicated that: 1. The discriminability of facial identity and expression mediate the relation between facial identity and expression recognition. Four possible discriminability combinations between identity and expression predicted 4 interference patterns between them. Low discriminability accounted for the interference either in facial identity judgment or in facial expression judgment task. 2. The measurements of eye movements indicated that either in facial identity or in facial expression recognition low discriminability led to a narrowly-distributed eye fixation pattern while high discriminability led to a widely-distributed eye fixation pattern. 3. By combining the morphing technique with the Garner paradigm, study 2 successfully demonstrated the linar relation between discriminability and Garner facilitation effects, confirmed the discriminability effects in the measurements of Garner facilitation effects.. 4. By providing the varying information of facial expression, study 2 revealed that varying information improved the discriminability of facial expression, and then enhanced the recognition of facial expression. All the results indicated that the discriminability of facial identity and expression could mediate the independent or interdependent processing between them, and the discriminability effects on recognition of identity and expression of unfamiliar faces was identified. The results from interference effects and facilitation effects both indicated that the dimensional relation between facial identity and expression was separable but not asymmetric claimed by previous studies(Schweinberger et al, 1998, 1999). Absolutedly independent or interdependent processing between facial identity and expression recognition were both impossible, discriminability of identity and expression mediated the relation between them. The discriminability effects revealed in present study could explain the conflicts between existing findings well.

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Coronary heart disease (CHD)is a common cardiovascular disease in the elderly, is also a typical psychosomatic disease. Personality factors are very important in many psychological factors impacting on the prognosis of patients with CHD. The most influential personality factors to CHD are Type A and Type D personality. The previous research has shown that although Type A personality increased the prevalence of CHD, it cannot predict the development and prognosis after diagnosis. In contradict, Type D personality can predict prognosis. There is still no clinic-based or theory-based answer to the question: Why Type A personality cannot predict the outcome while Type D personality could predict the prognosis independently. The current research conducted a systematic investigation to the above question, which included one comparison study between CHD patients and control group, and four studies on reaction experiment and answered the question: why Type A personality cannot predict whereas Type D personality could effectively predict prognosis of CHD. The findings of the current research were: Type A and Type D personality influence CHD prognosis through different psychological mechanisms: both dimensions of Type D personality have direct influence on social support, whereas neither dimensions of Type A personality related to social support, directly of indirectly. Negative affection component of Type D personality significantly related to anxiety and depression, Social repression significantly related to anxiety but not depression. Both dimensions of Type A personality significantly related to anxiety but not depression. Neither under rest or diaphragmatic breathing conditions, Type A personality had no significant influence on vestibular autonomic reaction among healthy young males. Neither Type A nor Type D personality had significant influence on vestibular autonomic reaction among old CHD patients under rest condition. Type D personality predicted lower sympathetic excitation under rest condition, and lower cardiac vagal tone under diaphragmatic breathing condition among healthy young males. When actively reacted to stimuli (math calculation) under rest condition, Type A personality increased sympathetic excitation among healthy young males. When actively reacted to stimuli (math calculation) under diaphragmatic breathing condition, Type A personality increased cardiac vagal tone among the same group of subjects. When actively reacted to stimuli under neither condition, Type D personality showed no significant influence on vestibular autonomic reaction among young males. When passively reacted to stimuli under neither condition, Type A personality showed no significant influence on vestibular autonomic reaction among young males. When passively stimulated followed rest, Type D personality increased sympathetic excitation and decreased cardiac vagal tone among young males. When passively stimulated followed diaphragmatic breathing, Typed showed no significant influence on vestibular autonomic reaction among young males. The above results indicated that Type A and Type D personalities had different psychological mechanisms to the outcome of CHD treatment: neither dimensions of Type A personality had direct or indirect effects on social support; both dimensions of Type D personality had direct and indirect effects on social support. Negative affection component of Type D personality significantly related to anxiety and depression, Social repression significantly related to anxiety but not depression. Both dimensions of Type A personality significantly related to anxiety but not depression. Social support positively related to the outcome after CHD treatment. The biological mechanisms of Type A and Type B personality to CHD prognosis differed in the following ways: Type A personality increased sympathetic excitation when actively stimulated, but had no influence when passively stimulated among young male subjects. When passively stimulated after rest, Type D personality predicted high sympathetic excitation and low cardiac vagal tone among young males, but not vestibular autonomic reaction among young males. Key words: Type A personality, Type D personality, Coronary Heart Disease (CHD), Prognosis, Psychobiological Mechanisms