Expert opinion-based multi objective optimization: an application in plasma coating technology

Multi-objective optimization is a very important activity which is applied in many different fields. When solving this problem, it is important to determine weights for criteria. If the weight of criteria is determined according to dry mathematical formulas, the opinion of researchers will be ruined. On the contrary, if the weight of criteria is determined according to the subjective opinion of researchers, it is also easy to make mistakes. This study applies a method of determining the weight of criteria based on experts' opinions and conditions must be also strictly satisfied, thereby both of the above limitations have been remedied. Such method is known as FUCOM (FUll COonsistency Method). An application example was carried out for multi-objective optimization in the plasma coating process. Plasma coating is a modern coating technology. This method is increasingly used in many different fields. However, determining the value of technological parameters to ensure the quality of high-quality products is a very complicated job. In order to ensure many requirements of the product, it is necessary to determine the optimal value of the technological parameters. Four criteria to evaluate a coating process include the adhesion strength of the coating, the shear strength of the coating, the tensile strength of the coating, and the porosity of the coating. The task of multi-objective optimization in this study is to determine the values of three input parameters (including: spray current intensity, powder feed flow, and spray distance) to ensure that the desired values of the four criteria are simultaneously achieved. After the weight of criteria is determined by the FUCOM method, the multi-objective optimization problem has been solved. Experiments to verify the optimal results were also conducted, thereby demonstrating the correctness of the methodology. The optimal values of the technology parameters (spray current intensity, powder feed flow, and spray distance) have been determined to be 568.69 A, 31.87 g/min, and 170.19 mm, respectivel

Stabilization for equal-order polygonal finite element method for high fluid velocity and pressure gradient

This paper presents an adapted stabilisation method for the equal-order mixed scheme of finite elements on convex polygonal meshes to analyse the high velocity and pressure gradient of incompressible fluid flows that are governed by Stokes equations system. This technique is constructed by a local pressure projection which is extremely simple, yet effective, to eliminate the poor or even non-convergence as well as the instability of equal-order mixed polygonal technique. In this research, some numerical examples of incompressible Stokes fluid flow that is coded and programmed by MATLAB will be presented to examine the effectiveness of the proposed stabilised method

Relationship Between Transformational Leadership and Organizational Learning Support Employee Creativity: Evidence from Vietnamese SMEs

Purpose: The current study aims to investigate the mediating role of organizational learning (OL) on the relationship between transformational leadership (TFL) and employee creativity (EC) in Vietnamese SMEs.   Theoretical framework:  The world underwent enormous and ongoing changes in SMEs after the Covid-19 pandemic. Leaders and employees must be more effective and adaptive to enhance systems and processes and meet client requests. Recently, SMEs in Vietnam have struggled to improve CEOs and staff with the professional credentials necessary to compete in the market and integrate.   Design/methodology/approach:  The framework and hypotheses were examined using SEM on SPSS and AMOS software to analyse the data after receiving 397 valid responses from SMEs in Vietnam.   Findings: Findings confirmed that TFL positively affects EC and OL. The role of individual motivation on individual consideration outweighs those of the other characteristics of TFL. OL played a partly mediator role in the relationship between TFL and EC.   Research, Practical & Social implications: This study provides an inventory of knowledge about the reality of OL and its mediating role on the relationship between TLF and EC, which contributes to enriching the library in overall and Vietnamese in specific in this subject.   Originality/value: This paper is one of the first papers in the Vietnamese SMEs context to address the mediating effect of OL between TLF and EC.

AMMONIA-BORANE BASED HYDROGEN STORAGE MATERIALS - A COMPUTATIONAL STUDY

Ph.DDOCTOR OF PHILOSOPH

Poverty Targeting and Impact of a Governmental Micro-credit Program in Vietnam

It is argued that without collateral the poor often face binding borrowing constraints in the formal credit market. This justifies a micro-credit program, which is operated by the Vietnam Bank for Social Policies to provide the poor with preferential credit. This paper examines poverty targeting and impact of the micro-credit program. It is found that the program is not very pro-poor in terms of targeting. Among the participants, the non-poor account for a larger proportion of loans. The non-poor also tend to receive larger amounts of credit compared to the poor. However, the program has positive impact on poverty reduction of the participants. This positive impact is found for all the three Foster-Greer-Thorbecke poverty measures.Micro-credit, poverty, poverty targeting, impact evaluation, instrumental variables, fixed-effect model