One of main methods for protecting nature is to use nature as an inspiration source for Designing new products for human being's needs. Movement and maneuver in fluids is an important issue in human activity. In this work, by inspiration from knife fish, an undulating fin for producing propulsion force are Designed and implemented. This undulating fin is a segmental anal fin, and produce sinusoidal waves which are needed for producing propulsion force. Then, parameters of this sinusoidal wave are discussed.In the fish robot, with using a special mechanical system, the direction of propulsive force is adjustable for controlling of direction and depth of swimming. Then, details of wireless control system for maneuvering and controlling of robot's speed are presented. Finally, the results of fish robot's movement is discussed experimentally.

The Design of experiment (DOE) has been used optimize the film thickness to improve corrosion property of metal parts. The DOE approach is applied to chromating process to improve the thickness of Zinc formed on the surface of low carbon steel. As it is the first time that such an experiments study has been carried out in Iran. The result of DOE can be applied in metal coating industries successfully.

Due to the expansion of educational methods for all study sciences in the present century, the need to instruction through practice and experimentation is felt more than ever in the educational process. experiments in the field of experimental sciences bring a wide range of thought and clear understanding to thinkers and students in this field. Practical action and experimental experimentation is a clear and tangible step in solving the challenges and abstract problems of teaching and understanding chemistry, and a visual and convincing solution that offers beyond human imagination in an understandable and observable context. During this research in the form of teacher experiences, we will review, brows and offer educational experiments that are prepared based on practical measures, and the implementation approach for chemistry education is approved. The purpose of this study is to make some academic tests suitable for students and to provide some examples of tests along with chapters of textbooks in which it is more appropriate to present the tests. Also, descriptions of laboratory activities are provided separately. In conclusion, the use of Designed experiments will be more useful for school students and more fruitful for college students. There are also some practical recommendations at the end of the research.

Real-world experiments are often multi-response. The correlation between responses and the cost of experimenting lead one to cast the problem as a multi-response model. Generation of a multi-response optimal Design is a challenging problem. There exist three general algorithms and all of them generate approximate Design and no method for multi-response n-exact Design has been cited in the literature. The existing methods have some drawbacks such as the necessity of solving many optimization problems in the process of generating an optimal Design, cumbersome manual operations and the complexity of performing sensitivity analysis. In this paper, we propose a Semi-Definite Programming (SDP) model for multi-response optimal Design. The proposed method is efficient because of solving a one shot optimization problem instead of many optimization problems, enjoying the recent advancements of interior-point solution algorithms and elimination of cumbersome manual operations. The proposed model has been tested on several test problems and proved to be very efficient since the optimal Designs were found very quickly in all cases. The robustness of the generated Designs with respect to the variance-covariance matrix is also assessed for those test problems in order to show how sensitivity analysis can be performed. The characteristics of the proposed method are also compared with those of other existing methods.

Numerical modeling of internal nozzle flow can be regarded as an essential investigation in the field of gasoline direct injection system of combustion engines since it is directly connected with fuel spray atomization and subsequently efficiency of exhaust gas emission. Internal nozzle flow can be changed and formed according to several parameters such as; system pressure, chosen fuel type, the orientation of spray holes according to injector axis, conicity of spray holes and distribution of spray holes on valve-seat, etc. The changes in these parameters also affect the formation of cavitation inside of whole domain, spray angle and create wall-wetting on the spray hole surfaces. The present work investigates the parameter and Design analysis in the valve-seat region of direct gasoline injection (GDI) injector using Computational Fluid Dynamics (CFD) and Design of experiments (DOE). CFD is employed to study the behaviors of internal flow inside the valve-seat region according to several Design parameters, whereas a mixed-level factorial Design is used to test the significance of the effects on the response variables. In conclusion, the effects of the most significant factors on response parameters as amount of vapor formation, spray (Tau) angle, and pre-hole wall wetting are determined for further efficient Design.

The wire drawing process is an essential technique in mechanical and industrial operations in lots of applications. Therefore, the current article aims to employ different methodologies (i.e., experimental, numerical) to investigate the optimum operating conditions and lubrication type on the surface and mechanical quality of these wires. By examining the effects of die angle, drawing speed, and lubricant type on wire drawing outcomes, the research not only provides valuable insights into process optimization but also contributes to reducing defects and enhancing wire properties. Results demonstrate significant variations in tensile strength based on these parameters, highlighting the need for precise control over process variables to achieve desired outcomes consistently. Moreover, statistical analyses reveal substantial relationships between process variables and tensile strength, offering a deeper understanding of the underlying mechanisms driving wire drawing performance. Overall, this research not only advances the understanding of wire drawing processes but also offers practical insights for improving wire manufacturing techniques, ultimately bolstering product quality, reducing costs, and increasing competitiveness in the global market.

The application of a flight simulator with six Degree of Freedom (6DOF) in Design and analysis of rocket systems is essential. The calibration of a 6DOF flight simulator is a challenging problem. This paper focuses on the calibration of a flight simulator and intends to answer the following questions:1) Does experimental Design have significant impact on calibration quality? If so, which experimental Design is suitable for calibration of a flight simulator?2) How to determine the suitable number of runs for calibration?3) Could DOE be used for estimation of calibration parameters? If so, how is it applied?The experiments have been conducted using a 6DOF simulator. Our investigation shows that the experimental Design has significant impact on the quality of calibration. The suitable Design for calibration of the 6DOF simulator is the triangular Design. A new method for determining the number of runs is proposed based on entropy function. It is also used for estimation of the calibration parameters. One advantage of the proposed method is the calibration of 6DOF simulator by considering several criteria such as range error, azimuth error and combination of these errors. The quality of calibration has been investigated by hypothesis testing.