This paper presents the results of thermodynamic analysis of the crude distillation units of two refineries in Nigeria. The analysis was intended to assess the thermodynamic efficiencies of the refineries and proffer methods of improving the efficiencies. Presented results show the atmospheric distillation units of the refineries have 33.3% and 31.6% exergetic efficiencies and 86.5% and 74.6% energetic efficiencies, respectively. Modifications of the operating and feed conditions of the refineries resulted in increased exergetic efficiencies for as much as 62.3% and 38.7% for the refineries. Thermodynamic analysis of the refineries can bring about efficiency improvement and effectiveness of the refineries.

To prepare a high-quality asymmetrical bending pipe of aluminum alloy by casting, the parting surfaces of the asymmetrical parts were determined based on the characteristics of the parts. Also, the forming process was designed and calculated. After that, the different types of gating systems were designed and the casting process was calculated by ProCAST, and then the influence of different casting gating systems on asymmetrical bending pipes was analyzed. The simulation results show that in the solidification process, although the filling speed of the single runner was slow, but the filling was stable. The gating system with a single runner-round flange filling system would lead to being more uniform for filling flow field and be sequential solidification of temperature field distribution, and stronger of the feeding ability. During the solidification process, the solid phase ratio of the single runner-round flange casting system is larger, and the shrinkage volume is smaller, which made the quality of castings better. Finally, a metal mold and core were made to cast a perfect asymmetric bending pipe of aluminum alloy product in a die casting machine. So the single runner-round flange filling system is suitable for asymmetrical bending pipe casting.

The primary goal of the study is to diagnose satisfaction and loyalty drivers in Polish retail banking sector. The problem is approached with Customer Satisfaction Index (CSI) models, which were developed for national satisfaction studies in the United States and European countries. These are multiequation path models with latent variables. The data come from a survey on Poles’ usage and attitude towards retail banks, conducted quarterly on a representative sample. The model used in the study is a compromise between author’s synthesis of national CSI models and the data constraints.

There are two approaches to the estimation of the CSI models: Partial Least Squares – used in national satisfaction studies and Covariance Based Methods (SEM, Lisrel). A discussion is held on which of those two methods is better and in what circumstances. In this study both methods are used. Comparison of their performance is the secondary goal of the study.