Velocity model-building for depth imaging of PS converted-wave data requires significantly more effort than PP imaging. For PS depth imaging, we must produce a model that flattens events on both PP and PS gathers and images equivalent events at the same depth for both data types. To satisfy these constraints requires a high-quality anisotropic model with accurate estimates of anellipticity and Vp/Vs ratio. We present a ray-trace tomography algorithm with floating event constraints that allows simultaneous update of all velocity model parameters for efficient and accurate velocity model-building with PP and PS data input. Tests on synthetic data with typical North Sea geology illustrate the effectiveness of the joint PP/PS tomography. Figure 5: PP (left) and PS (middle) CIP gathers with event picks overlaid, relative shift between PS and PP depth sections (right) and true depth minus image depth (far right) for PP/PS tomography model with well marker constraints.

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Illumination studies of targets in complex geologies is a central aspect in survey design, structural imaging and reservoir characterization, and require more accurate algorithms that properly describe the physical properties of wave propagation. Conventionally, illumination and resolution studies for survey design involve ray-based methods, and although they capture properly properties of simpler earth models, they suffer from severe limitations in accuracy in complex regions. Earlier work (Lapilli et al., 2010) introduced a method for target-oriented illumination studies where wave propagation accurately models the wavefield properties, and target-oriented illumination maps are constructed through local decomposition of synthetic seismograms. This target-oriented method presents a reduced modeling cost when compared to an illumination study where given acquisition geometries are fully modeled and migrated to obtain the imaged amplitudes at a selected target. This work presents results of a target-oriented wave illumination study constructed for presurvey analysis of a full azimuth acquisition geometry over a deep-water subsalt target. The resulting illumination map is compared with the predicted illumination maps of both a fully synthesized and depth migrated target amplitude map and ray-based amplitude map. Shot weights describing the contribution of energy to imaging a given target are also computed, results demonstrate these weights are more stable and adequate for amplitude studies as compared to ray-based results.

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Recently, extended-range electric vehicles are a new solution to energy shortage and environmental pollution, which effectively increases the range of electric vehicles, extends the battery life, and reduces fuel consumption. Therefore, this paper mainly focuses on the design of the EREV powertrain, building a vehicle model by using AVL CRUISE to simulate and verify the calculated parameters of the design. Analyzing the structural characteristics of the extended-range electric vehicle and determining the vehicle’s basic parameters and performance indexes using the Aratou Free 4WD hybrid as the prototype were the first part. In this part, the drive motor on the power system, battery, and range extender were selected based on the calculated parameters. The AC asynchronous motor, ternary lithium battery, and four-stroke gasoline engine were chosen as the components of the power system in the EREV. Building the vehicle model by using the AVL Cruise and developing the calculation tasks such as cyclic driving conditions, steady-state driving performance analysis, full-load acceleration performance calculation, and hill-climbing performance analysis were the second part. After the above steps, the simulation results analysis report showed that the powertrain design meets the target and potential of electric vehicle development. This paper provides a reference for comparing the dynamic property and economy of the extended-range electric vehicle with traditional fuel vehicles.