Evaluating levy flight parameters for random searches in a 2D space

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2013.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (pag 23).It is experimentally known that the flight lengths of random searches by foragers such as honey bees statistically belong to a power law distribution. Optimality of such random searches has been a topic of extensive research because knowing their optimal parameters may help applied sciences. Viswanathan et al. have shown the inverse-square power law to be the optimal law for such random searches. This thesis explores the capability of the model presented in such that it can be applied to Unmanned Autonomous Vehicles (UAVs). The thesis also identifies the minimum flight length, lmin, as an important factor that needs to be controlled based on the UAV's sensor range. We present a theoretical lmin as an explicit function of the sensor range, rv, and an estimated target density, p.by Mukul Kumar Singh.S.B

Gigas Growth of Carbon Nanotubes

An exceptionally high yield of carbon nanotubes (CNTs) has been achieved by chemical vapour deposition (CVD) of camphor over zeolite support. A simple 30 min CVD of 12 g camphor over Fe-Co-impregnated zeolite at 650 °C in an academic laboratory setup, yields 6 g multiwalled CNTs of dia ~10 nm with an as-grown purity of ~88 per cent. Owing to the enormous CNT growth,the zeolite bed inflates by 1000 wt per cent and 10,000 vol per cent. Camphor-to-CNT production efficiency is 50 per cent and net carbon-to-CNT conversion efficiency is 61per cent. These figures are incomparably higher than that of any CNT precursor by any method. Hence it is called‚gigas growth™. The technique greatly complies with the principles of green chemistry, and thus sets an example of an environment-friendly nanotechnology.Defence Science Journal, 2008, 58(4), pp.496-503, DOI:http://dx.doi.org/10.14429/dsj.58.167

Personalized Item Ranking from Implicit User Feedback: A Heterogeneous Information Network Approach

In today’s era of the digital world with information overload, generating personalized recommendations for the e-commerce users is a challenging and interesting problem. Recommendation of top-N items of interest to a user of e-commerce is highly challenging using binary implicit feedback. The training data is usually very sparse and have binary values capturing a user’s action or inaction. Due to the sparseness of data and lack of explicit user preferences, the recommendations generated by model-based and neighborhood-based approaches are not effective. Of late, network-based item recommendation methods, which utilize item related meta-information, are beginning to attract increasing attention for binary implicit feedback data. In this work, we propose a heterogeneous information network based recommendation model for personalized top-N recommendations using binary implicit feedback data. To utilize the potential of meta-information related to items, we utilize the concept of meta-path. To improve the effectiveness of the recommendations, the popularity of items and interest of users are leveraged simultaneously. Personalized weight learning of various meta-paths in the network is performed to determine the intrinsic interests of users from the binary implicit feedback data. To show the effectiveness, the proposed model is experimentally evaluated using the real-world dataset. Available at: https://aisel.aisnet.org/pajais/vol9/iss2/3

Oral Health related treatment needs among Autistic Children: A Review

Autism is a neurodevelopment disorder allied with atypical brain constitution and function due to which communication, speech, behaviour, and cognitive functions weaken. Autism patients have many emotional, physical, health-related issues and oral health is one of them. As oral health is a wide range reflection of our general health, thus to achieve a good overall health focus on oral health is equally important. Every child has a unique characteristic, thus their emotional, physical and health needs are different. Therefore, the aim of this paper is to review and discuss the literature related to oral health characteristics and treatment needs of children with Autism Spectrum Disorder to facilitate the provision of care by dental practitioners