Journal of Modern Processes in Manufacturing and Production
Volume:4 Issue: 3, Summer 2015

Honing is a process for finishing surfaces to obtain smooth surface. This process is used for final polish of inner parts such as engines cylinders. Optimizing this process has always been a big challenge for mass production of cylinder blocks of internal combustion engines. Honing process has some variable parameters, thus to get their optimum rates the automobile cylinders were tested. In this research, experiment design was done using Taguchi method and to make input constant parameters of the test consistence, cylinder was bored using boring machine and in the next phase, cylinder was honed according to the design of experiment. Abrasive particles were selected from the material of carbide silicone stone and the variable parameters considered in this test were tangential speed, grain size, and the number of tools course. In order to measure surface quality of each cylinder, roughness tester machine was used and surface quality considered as output parameters of machining. Then, the results of the test were studied and analyzed on software environment. According to the tests conducted, the optimum values of mesh stone of honing and optimum values of numbers related to the course number and rotation were identified on the best state.

Silica refractory bricks are used especially in the metallurgical industries, due to desirable properties such as particularly their high melting point and their rigidity and strength at high temperatures. In this research, different amount of SiC were added to Silica refractory containing different binders such as Borax, Boric acid, Calcium nitride, Sodium tri poly phosphate, Sodium hexametaphosphate (SHMP) and lime are added. Physical properties (density and porosity), mechanical properties (cold crush strength, CCS) and microstructure were studied. This study indicated that SiC improves the physical and mechanical properties. In general, increasing SiC with different binders improve the mechanical and compaction in the samples. Silica refractorysample containing 20%wt. SiC and 5% wt. borax as a binder had the best results of mechanical strength and compaction. In this sample, glassy phases formed fills the voids and increasing temperature between particles. In fact, glass phase formation increase compaction, density, and strength.

In magnetic abrasive finishing (MAF), abrasive grains as a tool move on surface and can remove chip from surface of work piece. In this study AL 6061 tube was considered as the work piece and the effect of finishing parameters such as gap distance between tube and poles, rotational speed of tube, abrasive ration and finishing time on surface roughness was investigated. The mixture of ferromagnetic grits (Fe) and Al2O3 grains was considered as the abrasives. The result showed increasing in rotational speed, finishing time and abrasive grains up to certain value decreases surface roughness and increasing in air gap increases surface roughness.

Modern manufacturing is under ever increasing pressure to develop solutions for highly complex tasks. In order to maintain the business survival in a highly competitive environment, it is vital to obtain customer satisfaction, which requires developing products with shorter lifecycles and higher quality meanwhile to reduce the production costs. In order to achieve such objectives a paradigm has been developed called “agile manufacturing”. However according to the literature, this tool has been widely used within the large companies, there is still an ongoing research to prove their applicability in Small and Medium Enterprises (SMEs). This paper aims to assess the feasibility of applying agile manufacturing principles within SMEs using 10 case studies in the UK and Malaysia. It contributes to theory by being able to identify the main barriers in the implementation of agile manufacturing by dividing them into three categories namely “lack of management skills”, “technological limitations” and “lack of workforce experience”. It also provides recommendations for each aforementioned issue so it could be used as guidelines for the industries to employ these methodologies.

The stock selection problem is one of the major issues in the investment industry, which is mainly solved by analyzing financial ratios. However, considering the complexity and imprecise patterns of the stock market, obvious and easy-to-understand investment rules, based on fundamental analysis, are difficult to obtain. Fundamental and technical analyses are two common methods for predicting the future behavior of the stock.Fundamental analysis focuses on the economic forces of supply and demand which cause stock prices change. On the other hand technical analysis examines historical data relating to changes in the price and trading volume by using graphs and indicators as a primary tool to predict future price movements. Therefore, in this paper, a model has been proposed for selection of the right portfolio in stock exchange. Financial industries ranking and companies ranking have been applied for selection of the right stock in this model. These rankings have been done through the PROMETHEE decision making method. Technical Analysis has been done for determining the right time to buy and sell the superior stocks. A survey has been done for determining the effective criteria over industry and company evaluation. The developed model has been applied in Tehran Stock Exchange (TSE) as a real case and a real problem has been solved. It is concluded that by using both Fundamental and Technical Analysis, an investor can get higher return on stocks instead of using just one individual analysis. In other words, while fundamental analysis distinguishes which stocks to buy, technical Analysis shows when to buy the superior stocks.Finally, some important and most commonly used indicators have been extracted. These indicators can be used by investors to consistently and correctly predict the future stocks prices.

In this paper, a robust PID control scheme is proposed for Micro-Electro-Mechanical Systems (MEMS) optical switches. The proposed approach is designed in a way which solves two challenging and important problems. The first one is successful reference tracking and the second is mitigating the system nonlinearities. The overall system composed of nonlinear MEMS dynamics and the PID controller is proven to be uniformly-ultimately bounded (UUB) stable in agreement with Lyapunov’s direct method in any finite region of the state space. Since the unmodeled but bounded dynamics of the system is systematically encapsulated in the system model, the only influence that this imposes on the stability is the respective bounds on the controller gains. The controller design strategy is simple and practicable with low computation burden which makes it easy to apply for control of MEMS optical switch. It also forms a constructive and conservative algorithm for suitable choice of gains in PID controller. The effectiveness of the proposed control law is verified through simulations in MATLAB/SIMULINK. It is shown that the proposed control law ensures robust stability and performance despite the modeling uncertainties.