Carbonate karst reservoir is the emphases of Tarim＇s carbonate exploration. However, it is buried at a large depth, which results in Weak seismic reflection signal and low S/N ratio. In addition, the karst reservoir ...Carbonate karst reservoir is the emphases of Tarim＇s carbonate exploration. However, it is buried at a large depth, which results in Weak seismic reflection signal and low S/N ratio. In addition, the karst reservoir contains great heterogeneity, so reservoir prediction is very difficult. Through many years of research and exploration, we have established a suite of comprehensive evaluation technology for carbonate karst reservoir using geophysical characteristics and a geological concept model, including a technique for reconstructing the paleogeomorphology of buried hills based on a sequence framework, seismic description of the karst reservoir, and strain variant analysis for fracture estimation. The evaluation technology has been successfully applied in the Tabei and Tazhong areas, and commercial production of oil and gas has been achieved. We show the application of this technology in the Lunguxi area in North Tarim in this paper.展开更多
The main goal of this research is to enhance the auditor＇s judgment ability in going concern opinion by applying bankruptcy prediction models as an analytical procedure. Data for this research have been collected thr...The main goal of this research is to enhance the auditor＇s judgment ability in going concern opinion by applying bankruptcy prediction models as an analytical procedure. Data for this research have been collected through questionnaires. The statistical population consists of auditors who are members of Iranian Association of Certified Public Accountants （IACPA）. The research results reflect that： （1） Auditors do not use statistical techniques for assessing going concern as an analytical procedure; （2） Auditors do not use these techniques as a tool to decrease the bias of judgments in assessing the going concern assumption; （3） Auditors do not use statistical techniques to assess audit risk in the planning stage; （4） Auditors do not use statistical techniques to assess audit risk in the final stage. Furthermore this research shows that auditors believe that the ＂standard concerning usage of analytical procedures needs more clarification＂ and ＂statistical bankruptcy predication models can help auditors in the planning stage＂. The other goal of this research is to show different auditor＇s judgments in assessing the going concern opinion with and without applying the bankruptcy prediction models as an analytical procedure. The result shows that the judgment of auditors toward the going concern assumption has improved by using statistical bankruptcy predication models.展开更多
Forecasting exchange rate is undoubtedly an attractive and challenging issue that has been of interest in different domains for many years. The singular spectrum analysis （SSA） technique has been used as a promising...Forecasting exchange rate is undoubtedly an attractive and challenging issue that has been of interest in different domains for many years. The singular spectrum analysis （SSA） technique has been used as a promising technique for time series forecasting including exchange rate series. The SSA technique is based upon two main choices： Window length, L, and the number of singular values, r. These values are very important for the reconstruction stage and forecasting purposes. Here the authors consider an optimum version of the SSA technique for forecasting exchange rates. The forecasting performances of the SSA technique for one-step-ahead forecast of six exchange rate series are used to find the best L and r.展开更多
基金This project is the applied fundamental research projects (04A10101) sponsored by the scientific and technology developmentdepartment of CNPC.
文摘Carbonate karst reservoir is the emphases of Tarim＇s carbonate exploration. However, it is buried at a large depth, which results in Weak seismic reflection signal and low S/N ratio. In addition, the karst reservoir contains great heterogeneity, so reservoir prediction is very difficult. Through many years of research and exploration, we have established a suite of comprehensive evaluation technology for carbonate karst reservoir using geophysical characteristics and a geological concept model, including a technique for reconstructing the paleogeomorphology of buried hills based on a sequence framework, seismic description of the karst reservoir, and strain variant analysis for fracture estimation. The evaluation technology has been successfully applied in the Tabei and Tazhong areas, and commercial production of oil and gas has been achieved. We show the application of this technology in the Lunguxi area in North Tarim in this paper.
文摘The main goal of this research is to enhance the auditor＇s judgment ability in going concern opinion by applying bankruptcy prediction models as an analytical procedure. Data for this research have been collected through questionnaires. The statistical population consists of auditors who are members of Iranian Association of Certified Public Accountants （IACPA）. The research results reflect that： （1） Auditors do not use statistical techniques for assessing going concern as an analytical procedure; （2） Auditors do not use these techniques as a tool to decrease the bias of judgments in assessing the going concern assumption; （3） Auditors do not use statistical techniques to assess audit risk in the planning stage; （4） Auditors do not use statistical techniques to assess audit risk in the final stage. Furthermore this research shows that auditors believe that the ＂standard concerning usage of analytical procedures needs more clarification＂ and ＂statistical bankruptcy predication models can help auditors in the planning stage＂. The other goal of this research is to show different auditor＇s judgments in assessing the going concern opinion with and without applying the bankruptcy prediction models as an analytical procedure. The result shows that the judgment of auditors toward the going concern assumption has improved by using statistical bankruptcy predication models.
基金supported by a grant from Payame Noor University, Tehran-Iran
文摘Forecasting exchange rate is undoubtedly an attractive and challenging issue that has been of interest in different domains for many years. The singular spectrum analysis （SSA） technique has been used as a promising technique for time series forecasting including exchange rate series. The SSA technique is based upon two main choices： Window length, L, and the number of singular values, r. These values are very important for the reconstruction stage and forecasting purposes. Here the authors consider an optimum version of the SSA technique for forecasting exchange rates. The forecasting performances of the SSA technique for one-step-ahead forecast of six exchange rate series are used to find the best L and r.
