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In this paper, taking the hydrodynamic modulation, the tilt modulation and the velocity bunching modulation into account, a SAR imaging simulation method based on the linear filtering method and the sea surface linear modulation theory is introduced. Firstly, a two-dimensional sea surface elevation is generated by linear filtering and sea wave spectrum. And then, the hydrodynamic modulation transfer function is employed. The scattering fields of various scattering cells are superposed to simulate the velocity bunching effect. Finally, we simulate coherent superposition process of multiple scattering echoes form targets in the course of radar flight.

Shunnan Block in North-West China is one of the toughest HPHT gas reservoirs with vertical depth over 7500 m, formation temperature over 200 and pressure gradient varying from 1.3 to nearly 2. The condition is close to temperature and pressure limit of well testing tools, therefore, the tools are hard to be sent to downhole and chances are that well testing operations usually failed. The pressure buildup data are with bad quality and needed to be converted into downhole data. Meanwhile, it's hard to diagnose accurate flow regimes and interprete because the block is typically carbonate reservoirs with porous medium including pores, natural fractures and caves. In this paper, we reviewed the exploration wells in this block and find that interpretation by pressure buildup or transient production data can only reflect part of the formation information; therefore the two kinds of data are combined to get more accurate interpretation results. For pressure buildup interpretation, three models including dual porosity model, composite model, and dual porosity with composite model are chosen and compared. For the production data, dual porosity model with boundary is selected because the wells usually show characteristics of multiple porous medium and boundary dominated flow. Parameters interpreted from pressure buildup data are simultaneously transferred into the model for production data. Results show that the combined interpretation by pressure buildup and production data can reduce the un-uniqueness of models as well as enhancing the accuracy of formation and wellbore parameters evaluation. The model and parameters can satisfy both pressure buildup and production data history. Although Shunnan block is considered as one greatly promising reservoir from the short period open flowing, the combined interpretations suggest very limited drainage volume. Reasons for this paradox phenomenon may be that the wells are severe contaminated by drilling fluid, or the wells were only producing gas in caves and natural fractures nearby the wells while other caves are not connected.

Neuroendocrine tumors (NETs) are neoplasms that arise from neural crest argyrophil cells, and often occur to the elderly, female and patients with cholelithiasis. In this case, the female patient was 38 years old and admitted into the hospital for interrupted right upward abdominal pain for 2 years plus aggravated with nausea and anorexia for 1 week. Ultrasound showed gallbladder space-occupying lesions and spectral computed tomography (CT) suggested of retroperitoneal lymph node metastasis. The patient was diagnosed with gallbladder neuroendocrine carcinoma after the surgery.