Electrical discharge machining (EDM) is one of the earliest non-traditional machining processes, based on thermoelectric energy between the workpiece and an electrode. In this process, the material is removed electro thermally by a series of successive discrete discharges between two electrically conductive objects, i.e., the electrode and the workpiece. The performance of the process, to a large extent, depends on the material, design and manufacturing method of the electrodes. Electrode design and method of its manufacturing also affect on the cost of electrode. Researchers have explored a number of ways to improve electrode design and devised various ways of manufacturing. The paper reports a review on the research relating to EDM electrode design and its manufacturing for improving and optimizing performance measures and reducing time and cost of manufacturing. The final part of the paper discusses these developments and outlines the trends for future research work.

No abstract

The use of nonbaffled vessels for mixing applications is becoming common in the biopharmaceutical industry but is not sufficiently well studied. Orientation of the impellers off-centered and/or at an angle is necessary to enhance mixing and eliminate swirling that would result without a baffle in a standard tank. This study focuses on characterizing mixing in vessels with the hydrofoil axial flow impellers mounted off-center at 10 degrees to the vertical. Geometrically similar vessels ranging from 100 to 5000 L working volume were used in this study. Mixing performance was successfully correlated to vessel geometric factors.

The major thrust of planned development in India has been on employment and income generation and self-reliance. The study evaluates ex-post income, output and employment linkages and import intensities of manufacturing sectors using an input-output model. It shows that among the four broad groups of industries, namely agrobased, non-agrobased final goods, intermediate and capital goods, agrobased industries through technological interdependence, particularly backward linkages, generate relatively more income and employment and use less imported inputs. The non-agrobased final goods industries with larger import requirements provide potential for income and employment generation if their required imported inputs are internalised.

No abstract