A novel approach for the NC tool-path generation of free-form surfaces is presented. Traditionally, the distance between adjacent tool-paths in either the Euclidean space or in the parametric space is kept constant. Instead, in this work, the scallop-height is kept constant. This leads to a significant reduction in the size of the CL (cutter location) data accompanied by a reduction in the machining time. This work focuses on the zig-zag (meander) finishing using a ball-end milling cutter.

High voltage conversion dc/dc converters have perceived in various power electronics applications in recent times. In particular, the multi-port converter structures are the key solution in DC microgrid and electric vehicle applications. This paper focuses on a modified structure of non-isolated fourport (two input and two output ports) power electronic interfaces that can be utilized in electric vehicle (EV) applications. The main feature of this converter is its ability to accommodate energy resources with different voltage and current characteristics. The suggested topology can provide a buck and boost output simultaneously during its course of operation. The proposed four-port converter (FPC) is realized with reduced component count and simplified control strategy which makes the converter more reliable and costeffective. Besides, this converter exhibits bidirectional power flow functionality making it suitable for charging the battery during regenerative braking of an electric vehicle. The steady-state and dynamic behavior of the converter are analyzed and a control scheme is presented to regulate the power flow between the diversified energy supplies. A small-signal model is extracted to design the proposed converter. The validity of the converter design and its performance behavior is verified using MATLAB simulation and experimental results under various operating states.INDEX TERMS Multi-port converter, electric vehicle, bidirectional dc/dc converter, battery storage, regenerative charging

Summary Electric vehicle (EV) systems are the promising future transportation system as they play a key role in reducing the atmospheric carbon emission, and it becomes the focal point of research and development in the current epoch. This paper presents the design and development of three‐port dc‐dc buck‐boost converter (TPB2C) applicable for EV. The main feature of the proposed converter is its ability to handle diversified energy sources of different voltage and current characteristics with high output gain. The designed single stage converter with reduced components count can be operated in buck, boost, and buck‐boost mode with partial bidirectional power flow capability. In addition, the TPB2C converter could provide buck and boost output simultaneously unlike its counterparts which can output either buck or boost output. In buck mode, the suggested topology charges the battery and thereby eliminates a separate battery management system. Roof top photovoltaic panel and battery are the two input sources for the suggested converter. A small‐signal model of the converter is developed using state‐space approach, and the steady‐state performance of the converter is analyzed comprehensively. The device level simulations carried out in MATLAB‐Simulink and the experimental laboratory prototype model are validated using a dSPACE1104 real‐time digital controller.

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Pipelines are the most efficient, cost effective and environmentally friendly means of fluid transport [1]. When selecting the route of a cross country pipeline, the goal is to route it so that it has the greatest utility to the public while minimizing negative impacts to people and the natural environment. In order to accomplish this goal of addressing several factors, a large amount of location based information needs to be analyzed. Hence the manual routing processes are very tedious in nature. The advent of new techniques like that of Geographic Information System (GIS) has made the routing process of pipelines more systematic and effective. This work identifies the various factors which need to be considered while routing a pipeline in the Indian scenario. A GIS to represent the various factors and automatically route the pipeline has been developed. A main drawback in the system is the lack of a structured methodology to derive the relative preferences of the different factors affecting the route. To address this issue, an AHP based methodology was developed. The GIS and the AHP methodology have been tested on case studies in the Indian scenario.