91 resultados para optimize


Relevância:

10.00% 10.00%

Publicador:

Resumo:

可变形机器人AMOEBA-I具有多种构形和多种转向方式.为实现机器人转向性能的优化,提出了可变形机器人的协同转向方法,并建立了相应的数学模型,对不同构形下的协同转向方式进行了理论分析.设定了机器人三个模块在协同转向过程中的运动关系,在此基础上给出了可变形机器人协同转向性能的评价指标.通过理论和实验比较了不同构形下的协同转向方式,实验验证了协同转向方法的有效性.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

本文介绍了星球探测机器人视觉系统的标定方法,首先介绍了一种新的从视觉坐标系到车体坐标系的变换方法,随后给出了像机的模型,在像机参数优化过程中将三维重投影误差作为评价函数,利用遗传算法完成寻优过程,以保证估计出的像机参数全局最优。真实环境实验结果表明:该方法具有较高的空间定位精度。

Relevância:

10.00% 10.00%

Publicador:

Resumo:

提出了一种新的最优模糊PID控制器,它由两部分组成,即在线模糊推理机构和带有不完全微分的常规PID控制器,在模糊推理机构中,引入了三个可调节因子xp,xi和xd,其作用是进一步修改和优化模糊推理的结果,以使控制器对一个给定对象具有最优的控制效果,可调节因子的最优值采用ITAE准则及Nelder和Mead提出的柔性多面体最优搜索算法加以确定,这种PID控制器被用来控制由作者设计的智能人工腿中的一个直流电机,仿真结果表明该控制器的设计是非常有效的,它可被用于控制各种不同的对象和过程。

Relevância:

10.00% 10.00%

Publicador:

Resumo:

提出了一种既能够在陆地上爬行,又能够在一定深度的水下浮游和在海底爬行的新概念轮桨腿一体化两栖机器人;多运动模式和复合移动机构是该机器人的突出特点.分析了轮桨腿复合式驱动机构的运动机理,并采用多目标优化设计理论和算法,对驱动机构的爬行性能和浮游特性进行了综合优化,得到了两栖机器人驱动机构的结构优化参数.虚拟样机的仿真结果证明了该轮桨腿一体化两栖机器人驱动机构的综合运动性能良好,对非结构环境具有一定的适应能力。

Relevância:

10.00% 10.00%

Publicador:

Resumo:

从并联机构与串联机构的运动学等效 ,并联机构本身特征与并联机构实际工作空间出发 ,考虑各分支末端误差对最终运动平台末端误差的影响 ,提出了并联机构位姿误差放大因子分析法·依据位姿误差放大因子具有对误差定量分析的特点 ,该分析方法既可用于机构参数优化 ,又可用于结构精度设计· 最后 ,给出了一个实例说明本方法的有效性·

Relevância:

10.00% 10.00%

Publicador:

Resumo:

基于PC和多轴运动控制器的开放式数控系统是理想的开放式数控系统。介绍了基于PMAC的开放式数控系统结构形式,PMAC的差补、位置控制、伺服功能、以PMAC和PC机为硬件平台搭建了数控系统,并对其硬件构成和软件设计结构进行了分析。着重从软件设计的角度,介绍了PTALK控件的功能和作用,对数控系统软件构成进行了详细的阐述。并设计出了友好的用户界面,在实际应用中具有重要意义。

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The problem of oil and gas migration and accumulation have been investigated for many years in petroleum geology field. However, it is still the most weak link. It is a challenge task to research the question about the dynamics of hydrocarbon migration and accumulation. The research area of this article,Chengbei step-fault zone is the important exploration area of Dagang oil field.The oil distribution is complicated in this area because of abundant faults and rock-reservoir-cap assemblage.In recent years, oil shows is often discovered, but no large-scale pool is found. The most important problem influencing exolore decision is lake of kowning about accumulation process of oil and resources potential. According to the geology characteristic and exolore difficult, the analysis principles of dynamics is used in this paper. The course from source to reservoir is considered as main research line, and relation of valid source rcok, migration dynamic and heterogeneous distribution of carrier is discussed especially in key time. By use of numerial model the couling of migration and passage is realized and dynamic process of oil migration is analysed quantitatively. On the basis of other research about structure and sendiment, basin model is built and parameters are choiced. The author has reconstructed characteristic and distribution of fluid dynamical in main pool-forming time by numerical model. The systems of oil migration and acuumulaiton are divided according to distribution of fluid potential. Furthermore, the scope of valid sourece rock and scale of discharging hydrocarbon is studied in geology history by the method of producting hydrocarbon poential. In carrier research, it is outstanding to analyse the function that fault controls the oil-gas migration and accumulation. According to the mechanism of fault sealing, the paper author puts forward a new quantitative method evaluating fault opening and sealing properties-fault connective probability by using the oil and gas shows in footwall and hangwall reservoir as the index of identifying fault sealing or non-sealing. In this method, many influencing factors are considered synthetically. Then the faut sealing propery of different position in third deimention of faults controlling hydrocarbon acummulation are quantitative evaluated, and it laies a foundation for building compex carrier systems. Ten models of carrier and dynamical are establishe by analysis of matching relation of all kinds of carriers in main pool-forming period. The forming process and distribution of main pathway has been studied quantitatively by Buoyancy-Percolation mode, which can conbine valid source rock, migration dynamical and carrier. On the basis of oil-gas migration and accumulation model, the author computes the loss of hydrocarbon in secondary migration, ahead of cap formation, and the quantity of valueless accumulation according to the stage of migration and accumulation and the losing mechamism. At the same time, resource potential is evaluated in every migration and accumulation system. It shows that the quanlity of middle systems arrive to 5.67×108t, which has a huge explore potential prospect. Finally, according to the result of quantitve analysis above mentioned, the favorable explore aims are forcasted by the way of overlapping migration pathway and valid trap and considering factors of pool-forming. The drilling of actual wells proved that the study result is credible. It would offer strong support to optimize explore project in Chengbei step-fault zone.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The technology of seismic acquirement has been more and more intact in both land area and marine area, however, since the acquirement equipment can not handle the tasks in this both two kinds of prospects at the same time, it is very hard to acquire in the prospect of seashore area, and also the quality of the raw data is poor, the related work in seashore area has been a tough task. With the development of the level of exploration, acquired equipment and technology, a certain series of processing methods has been built up, which enhanced the resolving power, the ratio of signal to noise and the quality of imaging, these methods could meet most of the requirements of exploration and the development. What is more, more and more nowadays prospects are composed by two or more 3D sub-prospect, the differences between frequencies, energy levels and the ratios of signal to noise are definitely obvious, we can not perform finely construct analysis and interpretation of reservoir without solving these problems in matching different raw data. As for the prospect that composed by both seashore and marine ones, through the analysis on the characteristics on frequency, amplitude, polarity and multiples of land prospect and marine prospect, the methods on how to eliminate those differences mentioned above were researched, and this paper gives a series of methods includes the computing of matching factor, recognizing of time difference, recognizing of phase difference, matching frequency, collapsing of abnormal energy, frequency compensating and so on, to fulfill the attenuations of energy difference, frequency difference, time difference and phase difference, and what is more, improve the innovative methods: includes the quantities method to synthetically and automatically recognize time difference and phase difference on the basis of signal match technology and according to statistic rule. And distinct the differences on phase and frequency characteristics of received raw data between velocity seismometer and piezoelectricity seismometer, and deduces that there are 90 degrees gap between data from these two seismometers, thirdly, synthetically apply zone abnormal frequency processing, surface consistent abnormal frequency compensate, residual abnormal frequency compensate, stack time equilibrium and optimize the processing seis-flow, deal with the would-be problems, such as low signal and noise rate, low resolution, poor imaging and poor state of consistent. Gain excellent effect in Da-gang oil field.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Evaluating the mechanical properties of rock masses is the base of rock engineering design and construction. It has great influence on the safety and cost of rock project. The recognition is inevitable consequence of new engineering activities in rock, including high-rise building, super bridge, complex underground installations, hydraulic project and etc. During the constructions, lots of engineering accidents happened, which bring great damage to people. According to the investigation, many failures are due to choosing improper mechanical properties. ‘Can’t give the proper properties’ becomes one of big problems for theoretic analysis and numerical simulation. Selecting the properties reasonably and effectively is very significant for the planning, design and construction of rock engineering works. A multiple method based on site investigation, theoretic analysis, model test, numerical test and back analysis by artificial neural network is conducted to determine and optimize the mechanical properties for engineering design. The following outcomes are obtained: (1) Mapping of the rock mass structure Detailed geological investigation is the soul of the fine structure description. Based on statistical window,geological sketch and digital photography,a new method for rock mass fine structure in-situ mapping is developed. It has already been taken into practice and received good comments in Baihetan Hydropower Station. (2) Theoretic analysis of rock mass containing intermittent joints The shear strength mechanisms of joint and rock bridge are analyzed respectively. And the multiple modes of failure on different stress condition are summarized and supplied. Then, through introducing deformation compatibility equation in normal direction, the direct shear strength formulation and compression shear strength formulation for coplanar intermittent joints, as well as compression shear strength formulation for ladderlike intermittent joints are deducted respectively. In order to apply the deducted formulation conveniently in the real projects, a relationship between these formulations and Mohr-Coulomb hypothesis is built up. (3) Model test of rock mass containing intermittent joints Model tests are adopted to study the mechanical mechanism of joints to rock masses. The failure modes of rock mass containing intermittent joints are summarized from the model test. Six typical failure modes are found in the test, and brittle failures are the main failure mode. The evolvement processes of shear stress, shear displacement, normal stress and normal displacement are monitored by using rigid servo test machine. And the deformation and failure character during the loading process is analyzed. According to the model test, the failure modes quite depend on the joint distribution, connectivity and stress states. According to the contrastive analysis of complete stress strain curve, different failure developing stages are found in the intact rock, across jointed rock mass and intermittent jointed rock mass. There are four typical stages in the stress strain curve of intact rock, namely shear contraction stage, linear elastic stage, failure stage and residual strength stage. There are three typical stages in the across jointed rock mass, namely linear elastic stage, transition zone and sliding failure stage. Correspondingly, five typical stages are found in the intermittent jointed rock mass, namely linear elastic stage, sliding of joint, steady growth of post-crack, joint coalescence failure, and residual strength. According to strength analysis, the failure envelopes of intact rock and across jointed rock mass are the upper bound and lower bound separately. The strength of intermittent jointed rock mass can be evaluated by reducing the bandwidth of the failure envelope with geo-mechanics analysis. (4) Numerical test of rock mass Two sets of methods, i.e. the distinct element method (DEC) based on in-situ geology mapping and the realistic failure process analysis (RFPA) based on high-definition digital imaging, are developed and introduced. The operation process and analysis results are demonstrated detailedly from the research on parameters of rock mass based on numerical test in the Jinping First Stage Hydropower Station and Baihetan Hydropower Station. By comparison,the advantages and disadvantages are discussed. Then the applicable fields are figured out respectively. (5) Intelligent evaluation based on artificial neural network (ANN) The characters of both ANN and parameter evaluation of rock mass are discussed and summarized. According to the investigations, ANN has a bright application future in the field of parameter evaluation of rock mass. Intelligent evaluation of mechanical parameters in the Jinping First Stage Hydropower Station is taken as an example to demonstrate the analysis process. The problems in five aspects, i. e. sample selection, network design, initial value selection, learning rate and expected error, are discussed detailedly.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Seismic exploration is the main method of seeking oil and gas. With the development of seismic exploration, the target becomes more and more complex, which leads to a higher demand for the accuracy and efficiency in seismic exploration. Fourier finite-difference (FFD) method is one of the most valuable methods in complex structure exploration, which has obtained good effect. However, in complex media with wider angles, the effect of FFD method is not satisfactory. Based on the FFD operator, we extend the two coefficients to be optimized to four coefficients, then optimize them globally using simulated annealing algorithm. Our optimization method select the solution of one-way wave equation as the objective function. Except the velocity contrast, we consider the effects of both frequency and depth interval. The proposed method can improve the angle of FFD method without additional computation time, which can reach 75° in complex media with large lateral velocity contrasts and wider propagation angles. In this thesis, combinating the FFD method and alternative-direction-implicit plus interpolation(ADIPI) method, we obtain 3D FFD with higher accuracy. On the premise of keeping the efficiency of the FFD method, this method not only removes the azimuthal anisotropy but also optimizes the FFD mehod, which is helpful to 3D seismic exploration. We use the multi-parameter global optimization method to optimize the high order term of FFD method. Using lower-order equation to obtain the approximation effect of higher-order equation, not only decreases the computational cost result from higher-order term, but also obviously improves the accuracy of FFD method. We compare the FFD, SAFFD(multi-parameter simulated annealing globally optimized FFD), PFFD, phase-shift method(PS), globally optimized FFD (GOFFD), and higher-order term optimized FFD method. The theoretical analyses and the impulse responses demonstrate that higher-order term optimized FFD method significantly extends the accurate propagation angle of the FFD method, which is useful to complex media with wider propagation angles.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Under the auspices of the 'knowledge-Innovation Program' of CAS, Institute of Geology and Geophysics has established the Broadband Seismic Laboratory. A new kind of 24-bit high-resolution seismograph DAS24-3B has been designed and manufactured in an effort of developing China's own technology of seismic array. Since these instruments will primarily be used in field operation, there is a need to optimize the system software of data acquisition system (DAS) to enhance its stability, compatibility and maintenance. The design ideas of the system software of DAS24-3B are partly learned from the advanced DAS 72A-08. In this system there are two exclusive communication programs DNAPI-COM1 and DNAPI-LPT1, which are suitable for all standard industrial computers with ECP parallel port and serial port. By these exclusive parallel and serial communication interface the system software is split into three parts, acquisition program, user's control program and graphical display program, which can function well in separate units and can run correctly in whole. The three parts of DAS24-3B's system software possess different functions and advantages. The function of acquisition program is to control the process of seismic data acquisition. DAS24-3B system reduced its power and harddisk read-write disturbance by using the extended memory attached to its CPU, which functions as enlarging the data buffer of system and lessening the times of harddisk read-write operations. Since GPS receiver of DAS is strongly sensitive to the around environment and has the possibility of signal loss the acquisition program has been designed with the ability to automatically trail the GPS locked time. The function of user's controlling program is to configure the system's work environment, to inform the user's commands to DAS, to trail the status of DAS in real-time. The function of graphical display program is to illustrate data in figures, to convert data file into some common formatted file, to split data file in parts and combine data files into one. Both user's control program and graphical display program are API (Application Programming Interface) in window 95/98 system. Both possess the features of clearness and friendship by use of all kind of window controls, which are composed by menu, toolbar, statusbar, dialogue box, message box, edit box, scrollbar, time control, button and so on. Two programs of systemic exception handles are provided to treat the trouble in field. The DAS24-3B DAS has been designed to be easier to use-better ability, more stable and simpler. It has been tested in field and base station and has been proved more suitable for field operation of seismic array than other native instruments.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Gas condensate reservoir research involves not only structure sediment reservoir liquid properties characterization but also the change of the temperature field, the change of the pressure field, the change of liquid phase and the reservoir sensitivity. To develop the gas condensate reservoir effectively .we must depict the static properties of the oil and gas system ,build exact and comprehensive parameter field, predict the rule of dynamic change and do the necessary reservoir characterization development plan dynamic prediction direct production. The MoBei Oil and Gas Field is the first gas condensate reservoirs which is found by the Xinjiang Oil Field Company in ZhunGaEr basin belly.it has deserved some knowledge after prospect evaluation, the MoBei Oil and Gas Field start development ,it is one of the important development blocks of Xinjiang Oil Field Company productivity constuction. During its development , it gradually appears some problems, such as complex oil and gas phase, great change of reservoir stretch .uncertain reservoir type and scale, controling its development strategy and plan difficultly. To deserve the high efficient development and long-term stable production of the gas condensate reservoir, it is necessary to characterize it systematically and form a suit of scientific development strategy. This thesis take the MoBei zone SanGongHe sand group reservoir as research object, applied advanced log techniques ,such as the nulear magnetism log ,MDT testing .etc. After comprehensive research of loging geology information, set up a suit of methods to identify oil gas water layer .these methods can identify the gas-oil level and the oil-water level. On the basis of reasonable development object system, according fine structure interpretation and structure modeling. build any oil water column height of the reservoir accurately. Through carefully analysis of the basic theory and method of reservoir seism prediction. optimize a reservoir inversion method .technique. software fitting the research region aiming strata, set up the GR field, porosity field, Rt field, impedence field .permeability field and initial oil saturation field, generating the base of quantity reservoir characterization. Discussing the characteristic of reservoir fluid and the movement and reallocating of muti-phase fluid in reservoir. And according the material of 100 soviet gas condensate reservoir ,build the recognition method and mode of gas condensate reservoir. Building the 3D geology model ,carry on the static and production evaluation, propose the development strategy and improve plan , provide the base of increasing reserves and advancing production and enriching the prospect development theory of the gas condensate reservoi

Relevância:

10.00% 10.00%

Publicador:

Resumo:

To pick velocity automatically is not only helpful to improve the efficiency of seismic data process, but also to provide quickly the initial velocity for prestack depth migration. In this thesis, we use the Viterbi algorithm to do automatic picking, but the velocity picked usually is immoderate. By thorough study and analysis, we think that the Viterbi algorithm has the function to do quickly and effectually automatic picking, but the data provided for picking maybe not continuous on derivative of its curved surface, viz., the curved face on velocity spectrum is not slick. Therefore, the velocity picked may include irrational velocity information. To solve the problem above, we develop a new method to filter signal by performing nonlinear transformation of coordinate and filter of function. Here, we call it as Gravity Center Preserved Pulse Compressed Filter (GCPPCF). The main idea to perform the GCPPCF as follows: separating a curve, such as a pulse, to several subsection, calculating the gravity center (coordinate displacement), and then assign the value (density) on the subsection to gravity center. When gravity center departure away from center of its subsection, the value assigned to gravity center is smaller than the actual one, but non other than gravity center anastomoses fully with its subsection center, the assigned value equal to the actual one. By doing so, the curve shape under new coordinate breadthwise narrows down compare to its original one. It is a process of nonlinear transformation of coordinate, due to gravity center changing with the shape of subsection. Furthermore, the gravity function is filter one, because it is a cause of filtering that the value assigned from subsection center to gravity center is obtained by calculating its weight mean of subsetion function. In addition, the filter has the properties of the adaptive time delay changed filter, owing to the weight coefficient used for weight mean also changes with the shape of subsection. In this thesis, the Viterbi algorithm inducted, being applied to auto pick the stack velocity, makes the rule to integral the max velocity spectrum ("energy group") forward and to get the optimal solution in recursion backward. It is a convenient tool to pick automatically velocity. The GCPPCF above not only can be used to preserve the position of peak value and compress the velocity spectrum, but also can be used as adaptive time delay changed filter to smooth object curved line or curved face. We apply it to smooth variable of sequence observed to get a favourable source data ta provide for achieving the final exact resolution. If there is no the adaptive time delay-changed filter to perform optimization, we can't get a finer source data and also can't valid velocity information, moreover, if there is no the Viterbi algorithm to do shortcut searching, we can't pick velocity automatically. Accordingly, combination of both of algorithm is to make an effective method to do automatic picking. We apply the method of automatic picking velocity to do velocity analysis of the wavefield extrapolated. The results calculated show that the imaging effect of deep layer with the wavefield extrapolated was improved dominantly. The GCPPCF above has achieved a good effect in application. It not only can be used to optimize and smooth velocity spectrum, but also can be used to perform a correlated process for other type of signal. The method of automatic picking velocity developed in this thesis has obtained favorable result by applying it to calculate single model, complicated model (Marmousi model) and also the practical data. The results show that it not only has feasibility, but also practicability.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Formation resistivity is one of the most important parameters to be evaluated in the evaluation of reservoir. In order to acquire the true value of virginal formation, various types of resistivity logging tools have been developed. However, with the increment of the proved reserves, the thickness of interest pay zone is becoming thinner and thinner, especially in the terrestrial deposit oilfield, so that electrical logging tools, limited by the contradictory requirements of resolution and investigation depth of this kinds of tools, can not provide the true value of the formation resistivity. Therefore, resitivity inversion techniques have been popular in the determination of true formation resistivity based on the improving logging data from new tools. In geophysical inverse problems, non-unique solution is inevitable due to the noisy data and deficient measurement information. I address this problem in my dissertation from three aspects, data acquisition, data processing/inversion and applications of the results/ uncertainty evaluation of the non-unique solution. Some other problems in the traditional inversion methods such as slowness speed of the convergence and the initial-correlation results. Firstly, I deal with the uncertainties in the data to be processed. The combination of micro-spherically focused log (MSFL) and dual laterolog(DLL) is the standard program to determine formation resistivity. During the inversion, the readings of MSFL are regarded as the resistivity of invasion zone of the formation after being corrected. However, the errors can be as large as 30 percent due to mud cake influence even if the rugose borehole effects on the readings of MSFL can be ignored. Furthermore, there still are argues about whether the two logs can be quantitatively used to determine formation resisitivities due to the different measurement principles. Thus, anew type of laterolog tool is designed theoretically. The new tool can provide three curves with different investigation depths and the nearly same resolution. The resolution is about 0.4meter. Secondly, because the popular iterative inversion method based on the least-square estimation can not solve problems more than two parameters simultaneously and the new laterolog logging tool is not applied to practice, my work is focused on two parameters inversion (radius of the invasion and the resistivty of virgin information ) of traditional dual laterolog logging data. An unequal weighted damp factors- revised method is developed to instead of the parameter-revised techniques used in the traditional inversion method. In this new method, the parameter is revised not only dependency on the damp its self but also dependency on the difference between the measurement data and the fitting data in different layers. At least 2 iterative numbers are reduced than the older method, the computation cost of inversion is reduced. The damp least-squares inversion method is the realization of Tikhonov's tradeoff theory on the smooth solution and stability of inversion process. This method is realized through linearity of non-linear inversion problem which must lead to the dependency of solution on the initial value of parameters. Thus, severe debates on efficiency of this kinds of methods are getting popular with the developments of non-linear processing methods. The artificial neural net method is proposed in this dissertation. The database of tool's response to formation parameters is built through the modeling of the laterolog tool and then is used to training the neural nets. A unit model is put forward to simplify the dada space and an additional physical limitation is applied to optimize the net after the cross-validation method is done. Results show that the neural net inversion method could replace the traditional inversion method in a single formation and can be used a method to determine the initial value of the traditional method. No matter what method is developed, the non-uniqueness and uncertainties of the solution could be inevitable. Thus, it is wise to evaluate the non-uniqueness and uncertainties of the solution in the application of inversion results. Bayes theorem provides a way to solve such problems. This method is illustrately discussed in a single formation and achieve plausible results. In the end, the traditional least squares inversion method is used to process raw logging data, the calculated oil saturation increased 20 percent than that not be proceed compared to core analysis.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Marine sponge cell culture is a potential route for the sustainable production of sponge-derived bioproducts. Development of a basal culture medium is a prerequisite for the attachment, spreading, and growth of sponge cells in vitro. With the limited knowledge available on nutrient requirements for sponge cells, a series of statistical experimental designs has been employed to screen and optimize the critical nutrient components including inorganic salts (ferric ion, zinc ion, silicate, and NaCl), amino acids (glycine, glutamine, and aspartic acid), sugars (glucose, sorbitol, and sodium pyruvate), vitamin C, and mammalian cell medium (DMEM and RPMI 1640) using MTT assay in 96-well plates. The marine sponge Hymeniacidon perleve was used as a model system. Plackett-Burman design was used for the initial screening, which identified the significant factors of ferric ion, NaCl, and vitamin C. These three factors were selected for further optimization by Uniform Design and Response Surface Methodology (RSM), respectively. A basal medium was finally established, which supported an over 100% increase in viability of sponge cells.