From Editor's Desk

Dr. N. Rama Murthy, Addl. Director (Retd.), CAIR (DRDO)

An all-electric vehicle, referred to as EV/AEV/electric car etc., gets all of its drive energy from its battery which must be recharged from an electric source. In this scenario, as one would expect, the amount of on-board stored energy in the battery will determine the range of the vehicle before every re-charge. The energy packing density in the batteries will impact the size and weight of the vehicle for a given range. As a result, energy density has been one of the primary concerns in the development of EVs. A major driving factor for the development of EVs is the pollution resulting from proliferation of Internal Combustion Engines (ICE) based vehicles.

In the cover page article on EVs, the author presents various issues and challenges to be overcome before EVs can replace ICE based vehicles. As he points out, challenges are formidable considering the fact that energy packing density in the fossil fuel based ICE is around 12000 watt-hours/kg as opposed to anywhere between 35-250 Watt-hour/kg for the batteries based EVs. The author brings out, the pros and cons of EVs and ICE based vehicles in detail as of today, and concludes that moving over to an EV eco system from an ICE eco system will not solve the problem of pollution and deteriorating environmental conditions.

Moving on to the next article, a significant component in effective communication amongst humans is usage of narratives. In a related interesting article titled, ‘The Story of Computational Narratology’ the author discusses the computational modelling of narratives which has generated enormous interest in fields like Natural Language Understanding (NLU), Natural Language Generation (NLG), and Artificial General Intelligence (AGI). The authors conclude that Narratology is an important area of study, which besides helping in explaining several cognitive, social, and cultural phenomena are expected to find myriad of practical applications with breakthrough in computational modelling of narratives.

In his article titled ‘Implementation of Residue Number System based Digital Filters’ which is a continuation of his article ‘Residue Number systems: A Primer’, that appeared June 2017 Issue, the author has addressed the practical implementation issues in realizing practical FIR digital filters and states that the techniques described can be extended to the realization of IIR digital filters as well.

Internet usage today is dominated by web browsers and mobile apps accessing online content which is done by a TCP connection. In a continuation article on Experiential Learning of Networking Technology Series, the authors explain how a client establishes a TCP connection with a server.

As before, I hope the readers will enjoy all the articles appearing in this edition.

Dr. N. Rama Murthy