YMCA University of Science and Technology

About: YMCA University of Science and Technology is a education organization based out in Faridabad, India. It is known for research contribution in the topics: Web page & Web crawler. The organization has 299 authors who have published 568 publications receiving 4547 citations.

Op-LEACH: An optimized LEACH method for busty traffic in WSNs

Abstract: A Wireless Sensor Network (WSN) is a collection of small, self-contained electro-mechanical devices that monitor the environment conditions. There are many design issues for WSNs such as deployment, mobility, infrastructure, network topology, network size and density, connectivity, lifetime, node addressability, data aggregation etc. The hierarchical routing protocols are LEACH (Low-Energy Adaptive Clustering Hierarchy) is one of the routing protocols designed for communication in WSNs. LEACH is clustering based protocol that utilizes randomized rotation of local cluster-heads to evenly distribute the energy load among the sensors in the network. LEACH uses localized coordination to enable scalability and robustness for dynamic networks, and incorporates data fusion into the routing protocol to reduce the amount of information that must be transferred to the base station. But LEACH is based on the assumption that each sensor nodes contain equal amount of energy which is not valid in real scenarios. LEACH uses a TDMA based MAC protocol, in order to maintain balanced energy consumption. A number of these TDMA slots are wasted when the nodes have random data distribution. A modification to existing LEACH protocol is needed in order to use the slots corresponding to nodes that do not have data to send at its scheduled slot. This paper presents a new version of LEACH protocol called OP-LEACH which aims to reduce energy consumption within the wireless sensor network. Both existing LEACH and proposed OP-LEACH are evaluated through extensive simulations using OMNET++ simulator which shows that Op-LEACH performs better than LEACH protocol.

Optimal placement of FACTS devices for voltage stability using line indicators

Abstract: Optimal location of FACTS (Flexible AC Transmission System) is very important for static voltage stability. This paper presents the determination of most unstable bus of system using P-V curve and eigenvalue analysis and the critical line using the stability indices. Voltage collapse indicators indices give exact information about the stability condition of a system and also determine the most insecure bus of the system. The line indices are evaluated for IEEE 14 bus system and critical line is found where the index reaches its maximum value. PSAT (power System Analysis Toolbox) software is used for Continuation Power Flow (CPF)) and the results shows that optimal placement of Unified Power Flow Controller (UPFC) significantly increase the loadability margin and stability of system.

Microstructural Evaluation of NiTi-powder, Steatite, and Steel Balls After Different Milling Conditions

Abstract: The present research deals with the investigation of morphological characteristics after mechanical alloying of Ni–50 at. %Ti in a high-energy planetary ball mill at various milling times (i.e., 4, 8, 30, 40, 50, and 60 h). Crystallite size was observed to be decreased with the increase of milling time, entire titanium fused in the nickel trellis, and results of intermetallic NiTi. The shape of particle also changed from lamella to globular. Steatite-ceramic and hardened balls were separately used for the ball milling. The observations of morphologies revealed that steatite balls are more durable and wear resistant as compared to steel ball. This research shows that ball milling with steatite-ceramic balls is a cost-effective, high purity, and productive step toward the formation of NiTi intermetallic compound with homogeneous composition and desired particle size.

A comparative study of multi criteria decision making approaches for risks assessment in supply chain

Abstract: Risk is inherent in almost every movement of supply chain partners. With the ever-increasing push for efficiency, supply chains today are getting more and more risky. Companies need to be vigilant with the increasing risks that can harm the short-term operations as well as the long-term sustainability of their supply chain. Academic interests appear to focus mostly on the risks associated with operation of supply chain. This paper highlights four areas of supply chain-related risks, i.e., transportation risks, operations risks, supplier related risks and market related risks. The purpose of this paper is to provide a framework to proactively manage supply chain risks. This study is an effort for risks assessment in supply chain and to find out the best alternatives. For this purpose, comparative study of multi criteria decision making approaches, analytical network process (ANP) and a multi-objective optimisation by ratio analysis (MOORA) technique for order preference are used. It also addresses the insinuations for supply chain managers as they balance a concern for risks with their efforts to search for, select, develop, and manage their set of supply chain partners.