Surface finish is one of the prime requirements of customers for mechanical parts. This research paper is focused on the analysis of optimum cutting conditions to get lowest surface roughness in turning by regression analysis. An experimental study was carried out to investigate the effect of cutting parameters like spindle speed, feed and depth of cut on surface finish in turning on Aluminum 7075 alloy. A multiple regression analysis (Ra) using analysis of variance is conducted to determine the performance of experimental measurements and to it show the effect of cutting parameters on the surface roughness. Multiple regression modeling was performed to predict the surface roughness by using machining parameters. Machining was done by using tungsten carbide tool. The objective was to establish correlation between cutting speed, feed rate and depth of cut and optimum the turning conditions based on surface roughness. These correlations are obtained by multiple regression analysis (RA).

This study analyzes the trends and determinants of FDI inflow to Ethiopia from India and China. It is based on panel data of 2 decades (1997–2016). It employs a gravity model approach and fixed effects estimation technique to identify factors governing the flow of FDI to Ethiopia. Factors affecting the flow of Indian FDI to Ethiopia include Ethiopia’s trade with India, India’s population size, GDP of Ethiopia, GDP PC of India, real interest rate, credit access and FDI openness in Ethiopia. Similarly, factors governing Chinese FDI flow to Ethiopia include Ethiopia’s GDP growth, Ethiopia’s trade with China, FDI openness and secondary school enrolment. Government expenditure in the host country reduces China’s and India’s FDI inflow. The traditional explanatory variable, a resource rent, is not found significant in explaining FDI in flow from China and India. The FDI inflow from India and China showed an increasing trend with an average rate of 82% and 202%, respectively, during the two-decade period. But the overall trend for both partner countries showed fluctuation across years. We can conclude that FDI from India is responsive to macroeconomic variables such as OER, real interest rate and liberalization measures such as trade openness in Ethiopia. FDI and trade flows from China are positively related to one another and cheap labour is an important attraction factor for Chinese FDI inflow. Policy makers in Ethiopia can focus on macroeconomic reform in case of the country’s relation with India whereas they focus on maintaining cheap labour cost, GDP growth and trade transactions with China.

Concrete elements exposed to fire undergo temperature gradients and, as a result, the surface layers spall, exposing steel reinforcement. Relatively few studies have been undertaken on heat-induced changes in fly ash concrete. The structural property of concrete that has been studied most widely as a function of heat exposure is compressive strength. Less attention has been given to flexural strength as influenced by heat exposure. Therefore, to investigate the effect of temperature on the flexural strength of fly ash concrete, the present study was carried out with M28, M33 and M35 grades of concrete. Concrete specimens 100 mm × 100 mm × 500 mm with partial replacement of cement by fly ash (10%, 20% and 30% replacement levels) were heated to 100°C, 200°C and 250°C for 1 h, 2 h and 3 h duration in an electric oven. The specimens were tested for flexural strength in the hot condition immediately after removing from the oven. The fly ash concrete showed consistently the same pattern of behaviour as that of concrete without fly ash under elevated temperatures during flexure. The fly ash concrete with fly ash content up to 20% showed improved performance compared with the specimens without fly ash by retaining a greater amount of its strength.

This paper introduces a simplified inverter circuit using a single dc source and an H-bridge with a least possible number of “switching devices”. This topology does not employ multiple “dc sources”, which enhances the reliability of the configuration. The topology consists of two parts, namely: “Level generation parts” as well as “Polarity generation parts”, it is the mixture of some of the switching devices, DC-link capacitor and a single DC source completes the part of level generation. The H-bridge in the proposed structure produces the polarity generation part. A detailed explanation of the modulation system and operating modes of the proposed framework are discussed. Finally, in the MATLAB/SIMULINK platform, the projected network topology is simulated and the outcomes are presented.

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