Analysis of Spacecraft Relative Motion and Applicability of Hill's Solution

研究了空间飞行器编队中最具基础性的问题之一,即相对运动的解析表达及Hill方程的适用条件。通过建立相对运动的通解公式,针对不同性质的初值深入地分析了其相对运动轨迹的本质特征,并给出了Hill方程的适用条件。此外,文中还给出了一个新的编队设计简化公式。

Hill Instability Analysis Of Tlp Tether Subjected To Combined Platform Surge And Heave Motions

This paper presents the Hill instability analysis of Tension Leg Platform (TLP) tether it, deep sea. The 2-D nonlinear beam model which is Undergoing Coupled axial and transverse vibrations, is applied. The governing equations are reduced to nonlinear Hill equation by use of the Galerkin's method and the modes superposition principle. The Hill instability charted Lip to large parameters is obtained. An important parameter M is defined and can he expressed as the functions of tether length, the platform surge and heave motion amplitudes. Some example studies are performed for various environmental conditions. The results demonstrate that the nonlinear coupling between the axial and transverse vibrations has a significant effect on the response of structure.. It needs to be considered for the accurate dynamic analysis of long TLP tether subjected to the combined platform surge and heave motions.

Extending Tsai-Hill and norris criteria to predict cracking direction in orthotropic materials

methods of lifetime measurement are discussed.

航天器相对运动与Hill解的适用性分析

研究了空间飞行器编队中最具基础性的问题之一，即相对运动的解析表达及Hill方程的适用条件。通过建立相对运动的通解公式，针对不同性质的初值深入地分析了其相对运动轨迹的本质特征，并给出了Hill方程的适用条件。此外，文中还给出了一个新的编队设计简化公式。

意大利威尼托（Veneto）的刺叶栎林-植物社会学生物多样性研究

刺叶栎( Quercus ilex L．)是地中海的常绿树种，属于古老的第三纪植物区系成份。本文根据苏黎世——蒙特利尔学派的植被学基本原理，全面地研究了分布在整个威尼托(Veneto)大区的剌叶栎林，详细研究刺叶栎林的群落组成、结构及类型划分。同时，对威尼托的刺叶栎林同北京山区的栎林进行了比较研究。最后，着重研究了威尼托刺叶栎林的生物多样性。 威尼托的刺叶栎林主要分布在亚得里亚海沿岸（包括Foci del Tagtiamento和Bosco Nordio e Rosolina Mare两地）、Lago di Garda和Colli Euganei。 在气候上，亚得里亚海沿岸属于半地中海气候。加尔达湖区域(Laqo di Garda)则是接近欧洲中部的大陆性气候，且维持半地中海的气候特点。Co t l i Euganei是这两地气候的过渡类型，且更接近亚得里亚海沿岸的类型。 在亚得里亚海沿岸的刺叶栎林可以分为三类，第一类(I)是一些矮树丛，这是Fraxinus ornus和Quercus ilex混交林的前身，较干旱。第二类群落(II)缺少乔木层，灌木层是由一些盖度不大的刺叶栎代替，更干旱。第三类群落(Ⅲ)是一群在外貌上相同的成熟群落．Fraxinus ornus和Quercus ilex得到充分发展，较中生。 在加尔达湖区的刺叶栎林可划分为三类。第一类群落(I)代表一组耐旱、开敞的矮树丛，含有Sesterio Variae-Ostryelum群丛的特征种，这一类可划分为SesLerio Variae-Ostryetum群 丛，土壤贫脊和干旱。第二类群落(Ⅱ)代表一类较郁闭的矮树丛，含有较多的Prunetalia群落目的成份，土壤较贫脊。第三类群(Ⅲ)代表一类郁闭的群落，乔木具有很大的密度因而林下灌木不能充分发展。SesLerio Variae-Ostryetum群丛和Prunetalia群落目的成份均不多。 在Colli Euganei的刺叶栎林可划分为二类。第一类群落(I)是一些不郁闲的矮树林组成。大体上分为地中海旱生栎林和地中海假灌丛。第二类群落(II)代表了较中生状态的植被，刺叶标种群绝对郁闭。 北京地处华北大平原的西北部。北京山地的气候为温带陆地性季风气候，其地带性的落叶阔叶林是以栎林为典型。虽然这些栎林同意大利威尼托刺叶栎林是两种不同的森林类型，但两者之间是存在着一定的联系。其共有的科有20个，共有属有11个。他们在植物组成中，以禾本科，蔷薇科和豆科的植物种类为最多。在乔木层中，他们都是以壳斗科的栎属(Quercus)为优势，其中木犀科的白蜡属(Fraxinus)和槭树属(Acer)较多。 本文对威尼托大区刺叶栎林的物种多度分布格局进行了全面探讨，计算出刺叶栎林的几何分布模型、Broken-stick分布模型、Log分布模型、Log-normat分布模型等四种物种多度分布的理论模型，并将这些理论分布模型用“序列／多度”图解和“多度／频度”图解表示出来。其中，几何分布模型．Broken-stick1分布模型用“序列／多度”图解表示。Broken-stick2分布模型、Log分布模型、Log-normal分布模型用“多度／频度”图解表示。 对上述四个物种多度的理论分布同实际现察的物种多度分布进行X2分析，在5％的显著性水平上，对整个威托大区的刺叶 栎林，几何分布模型最能代表其物种多度分布，显著性最大;Log-normal分布模型也可以用来代表威尼托刺叶标妹的物种多度分布，其显著性次于几何分布模型的显著性。这表明威尼托的刺叶栎林尚处于演替的早期阶段，这些刺叶栎林曾受到严重破坏，现正在恢复。 通过比较Foci del Tagtiamento和Bosco Nordio加尔达湖区、Colli Euganei四个地方刺叶栎林的物种多度的几何分布模型和Log-normal分布模型，显示出Lago di Garda（加尔达湖区）的刺叶栎林生物多样性最好、Foci del Tagtiamento刺叶栎林生物多样性较好．Bosco Nordio的剌叶栎林生物多样性较差．Colli Euganei的刺叶栎林生物多样性最差。 再利用多样性指数计算全部威尼托大区剌叶栎林的生物多样性。计算的多样性指数有丰富度指数（包括Margalef指数、Men-hinick指数、Monk指数）、多样性指数(Shannon信息指数、Bri llouin个息指数、Gini指数、PIE指数、Mcintosh指数)、优势度指数(Berger-Parker指数、Simpson指数)、均一度指数(Pielou均一度指数、Brillouin均一度指数，PIE的V’均一度指数．PIE的V均一度指数，N2的V’均一度指数，N2的V均一度指数，Mclntosh均一度指数，Hill的F10均一度指数，Hill的E21均一度指数，Hill的F21的一度指数）。通过比较丰富度指数，多样性指数、均一度指数与优势度之间的关系，结果，Simpson优势度指数同Men-hinick物种丰富度指数、Shannon信息指数、Bril-louin信息指数、Pielou均一度指数，Brillouin均一度指数，Mcintosh均一度指数、PIE的V’均一度指数呈负相关关系，因此，上述生物多样性指数可以较好地反映威尼托大区刺叶栎林的生物多样性。反映出的结果是：加尔达湖区刺叶栎林生物多样性最好，Foci del Tagtiamento刺叶栎林生物多样性较好，Bosco Nordio的剌叶栎林生物多样性较差．Colli Euganei的刺叶栎林生物多样性最差。 生物多样性的研究显示出生物多样性同生境状况的密切联系。往往受人为干扰严重的群落生物多样性低、如Coli Euganei和亚得里亚海岸刺叶栋林;而受人为破坏较轻的群落其生物多样性高，如加尔达湖区刺叶栎。 生物多样性的研究还显示出生物多样性同群落演替的发展阶段密切相关，在群落演替初期，由于缺乏优势种，而又有大量物种侵入，物多样性相对较高。在群落演替中期，由于形成了一个或几个优势种，优势度的增加导致了生物多样性相对减低。如Foci del Tagtiamento刺叶栎林生物多样性高于Bosco Nordio刺叶栎林的生物多样性。到演替后期，随着更多物种的侵入，群落结构的复杂化、生物多样性又将逐步提高。

Explanation for Micromorphologies Around Broken Fibers in Fiber-Reinforced Composites

Experimental observations on micromorphologies around broken fibers in glass-fiber-reinforced epoxy matrix composites reveal different kinds of highly oriented patches at the circumambience of broken fibers, whereas the bulk of the matrix has been observed to be largely isotropic. These patches are interpreted to correlated areas where the stress gradients of the matrix are formed after fiber breaking, but the underlying cause for the orientation is still unknown. The authors have modified an embedded cell model to explain the experimental phenomena. The finite element simulation indicates that the surfaces around broken fibers display a change from an extension micromorphology to a mixed tension and shear micromorphology with the increase of applied strain.

Application of forecasting structural cracks technique of 3D move in Chengdao buried hill

3DMove software, based on the three-dimension structural model of geologic interpretation, can forecast reservoir cracks from the point of view of formation of the structural geology, and analyze the characteristics of the cracks. 3DMove software dominates in forecasting cracks. We forecast the developments and directions of the cracks in Chengbei buried hill with the application of forecasting technique in 3DMove software, and obtain the chart about strain distributing on top in buried hill and the chart about relative density and orientation and the chart about the analysis of crack unsealing. In Chengbei 30 buried hill zone, north-west and north-east and approximately east-west cracks in Cenozoic are very rich and the main directions in every fault block are different. Forecasting results that are also verified by those of drilling approximately accord with the data from well logging, the case of which shows that the technique has the better ability in forecasting cracks, and takes more effects on exploration and exploitation of crack reservoir beds in ancient buried hill reservoirs.

Geophysical evaluation methods for buried hill reservoirs in the Jiyang superdepression of the Bohai Bay basin, eastern China

The Jiyang superdepression is one of the richest hydrocarbon accumulations in the Bohai Bay basin, eastern China. Comprehensive seismic methods have been used in buried hill exploration in Jiyang to describe these fractured reservoirs better. Accurate seismic stratigraphic demarcation and variable-velocity mapping were applied to reveal the inner structure of the buried hills and determine the nature of the structural traps more precisely. Based on the analysis of rock properties and the characteristics of well-developed buried hill reservoirs, we have successfully linked the geology and seismic response by applying seismic forward technology. Log-constrained inversion, absorption coefficient analysis and tectonic forward-inversion with FMI loggings were applied to analyse and evaluate the buried hill reservoirs and gave satisfying results. The reservoir prediction was successful, which confirmed that the comprehensive utilization of these methods can be helpful in the exploration of buried hill reservoirs.

海拉尔盆地贝尔凹陷基岩潜山特征及储层预测

The lithology of the buried hill of Triassic Budate group in Beier depression is epimetamorphic clastic rock and volcanic clastic rock stratum. Recently the favorable hydrocarbon show was discovered in buried hill of base rock, and large-duty industrial oil stream was obtained in some wells in Beier depression. Based on the information of seismos and wells, the tectonic framework, tectonic deformation times and faulted system of the Beier depression are comprehensively studied, then configuration, evolutional history, genetic type and distributed regularity of buried hill are defined. According to observing description and analysis of core sample, well logging and interpretive result of FMI, the lithological component, diagenetic type and diagenetic sequence of buried hill reservoir are confirmed, then reservoir space system of buried hill is distinguished, and vegetal feature, genetic mechanism and distributed regularity of buried hill fissure are researched, at the same time the quantitative relationship is build up between core fissures and fissures interpreted by FMI. After that fundamental supervisory action of fault is defined to the vegetal degree of fissure, and the fissure beneficial places are forecasted using fractal theory and approach. At last the beneficial areas of Budate group reservoir are forecasted by reservoir appraisal parameters optimization such as multivariate gradually regression analysis et. al. and reservoir comprehensive appraisal method such as weighing analyze and clustering procedure et. al. which can provide foundation for the next exploratory disposition. Such production and knowledge are obtained in this text as those: 1. Four structural layers and two faulting systems are developed, and four structural layers are carved up by three bed succession boundary surfaces which creates three tectonic distortional times homology. Three types of buried hill are divided, they are ancient physiognomy buried hill, epigenetic buried hill, and contemporaneous buried hill. 2. Reservoir space of Budate buried hill is mainly secondary pore space and fissure, which distributes near the unconformity and/or inside buried hill in sections. The buried hill reservoir experienced multi-type and multi-stage diagenetic reconstruction, which led to the original porosity disappeared, and multi secondary porosity was created by dissolution, superficial clastation and cataclasis et. al. in diagenetic stage, which including middle crystal pore, inter crystal pore, moldic pore, inter particle emposieu, corrosion pore space and fissure et. al. which improved distinctly reservoir capability of buried hill. 3. The inner reservoir of buried hill in Beier depression is not stratigraphic bedded construction, but is fissure developing place formed by inner fault and broken lithogenetic belt. The fissures in inner reservoir of buried hill are developed unequally with many fissure types, which mainly are high angle fissure and dictyonal fissures and its developing degree and distribution is chiefly controlled by faulting. 4. The results of reservoir comprehensive evaluate and reservoir predicting indicates that advantageous areas of reservoir of buried hill chiefly distributes in Sudeerte, Beixi and Huoduomoer, which comprehensive evaluate mainly Ⅱand Ⅲ type reservoir. The clues and results of this text have directive significance for understanding the hydrocarbon reservoir condition of buried hill in Beier depression, for studying hydrocarbon accumulated mechanism and distributed regularity, and for guiding oil and gas exploration. The results of this text also can enrich and improve nonmarine hydrocarbon accumulated theory.