Reducing the exhaust emissions of a spark ignition engine by means of engine modifications requires consideRATIOn of the effects of these modifications on the variations of crankshaft torque and the engine roughness respectively. Only if the roughness does not exceed a certain level the vehicle do not begin to surge. This paper presents a method for controlling the air-fuel RATIO for a lean burn engine. Fuzzy rules and reasoning are utilized on-line to determine the control parameters. The main advantages of this method are simple structure and robust performance in a wide range of operating conditions. A non-linear model of an ST engine with the engine torque irregularity simulation is used in this study.

This paper presents a practical implementation of explicit self-TUNING control to a hydraulic robot for trajectory tracking. The proposed control strategy is simple, however, adapts itself to system variations such as load changes, noise and disturbances and it may be suitable for non-minimum phase control systems. Computational complexity of self-TUNING control is not a limitation anymore because of increased computing power of computers even for high speed applications. This situation makes the self-TUNING control an important alternative to PID control, which is the most widely used controller in industrial processes. Extensive experiments conducted on hydraulic robots to demonstrate and verify the control performance of the proposed self-TUNING control in comparison with the traditionally designed, PID control.

Fine-TUNING Argument (PTA) starts with the claim that the physical constants, the laws of nature and, accordingly, the interconnections between the parts of the physical world have been fine-tuned such that we may infer the existence of some supernatural fine-tuner whose attributes, inferred through some other possible inferences, may allow calling him "God". FTA, at both local and global/universal levels, takes the empirical data of natural sciences as the evidence of the intelligent purposeful agent having a hand in the origin, structure, and evolution of the universe, so that the apparent cosmic coincidence among the physical constants as well as .the events, from physical to biological and psychological ones, indicate some purposeful fine-TUNING leading to a life-permitting and even intelligence-permitting world. Now, PTA may be considered as the most popular variety of Teleological Argument and Design Argument that has attracted the attention of some specialists among the scientists, theologians and philosophers interested in searching some sound argument for the existence of God based not on religious sacred texts but on human cognitive faculties. But PTA, like Teleological Argument and Design Argument, suffering some problematic features, needs philosophical elucidation and evaluation. In this paper, the author, sympathetic towards those who try to scientifically and philosophically RATIOnalize their belief in the fine-tuner/designer/maker/creator of the world, and have a trust on PTA, tries to examine the "argument" on the basis of some Islamic and Western philosophical achievements. The, author, willing to disagree with any ultimate agnosticism and negativism, tries to show the weak and strong features of PTA to help the believers, in particular those who have a theological trend and position, to know the weaknesses of the "Argument", on the one hand, and its capacities in the face of both its deniers and rivals, on the other hand.

The effectiveness of multiple tuned mass friction dampers (MTMFD) for vibRATIOn control of structure over a single tuned mass friction damper (STMFD) is investigated. A five story structure supported with MTMFD is considered and the governing differential equations of motion are derived. The response of the structure under four selected earthquake ground motions is obtained by solving the equations of motion numerically using the state space method. The number of damper in MTMFD is varied and the response of five story structure with STMFD is compared with the response of the same structure with MTMFD. A parametric study is also conducted to investigate the effects of important parameters such as number of dampers in MTMFD, damper frequency spacing, mass RATIO, TUNING RATIO and damper slip force. It is found that for a given structural system and level of excitation an optimum value of the parameters (i.e. frequency spacing, TUNING RATIO and damper slip force) exists at which the peak displacement of structure attains its minimum value. The response time history of the structure with STMFD and MTMFD with respect to their optimum parameters is compared. It is found that the MTMFD is more effective in controlling the response of the structure in comparison with the STMFD having the same mass.