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Abstract Visual examination of the surface topography, in conjunction with the other sensors, may confirm the existence of chatter. Online chatter detection during real machining operations is possible with the use of sensors, and the presence of noise in their output and restricted bandwidth are the major drawbacks of these sensors. Productivity drops and manufacturing costs go up when there is a lot of chatter in the machining process. In the present paper, an integrated spindle tool system is modeled using finite element method with Timoshenko beam theory including rotational and shear deformation effects. To maximize the average stable depth of cut in an end milling process while simultaneously minimizing the chatter vibration levels, real time and offline strategies have been investigated. Machining experiments performed on Al6061-alloy specimens provide an empirical confirmation of the stability boundaries. The surface topography methods such as scanning electron microscope (SEM) and optical microscope images along with vibration levels are considered, to identify chatter marks under various machining conditions, which helps to assure cutting process stability. Stability lobe diagrams are plotted with these derived conditions and observed at an incremental level in the axial depths of the cut. The methodology shown in this paper improves the machining stability of the end milling with the reduction in the tool tip vibrations.

Mobile ad hoc networks (MANETs) are collections of wireless mobile devices with restricted broadcast range and resources, and no fixed infrastructure. Communication is achieved by relaying data along appropriate routes that are dynamically discovered and maintained through collaboration between the nodes. Discovery of such routes is a major task, both from efficiency and security points of view. A security model to the specific requirements of MANETs was introduced among the novel a characteristic of this security model is that it promises security guarantee under concurrent executions, a feature of distributed computation. A novel route discovery algorithm called endairA was introduced, together with a claimed security proof within the same model. In this paper, we show that the security proof for the route discovery algorithm, vulnerable to a hidden channel attack and the security framework. [ABSTRACT FROM AUTHOR]

DC-DC converters generally maintain poor efficiency when operating at light to medium loads. This is primarily due to the fact that switching losses outweigh conduction losses significantly, while core losses remain constant regardless of the load conditions. In the case of the interleaved boost converter (IBC), this efficiency deterioration increases more than the conventional boost converter (CBC), when the number of phases increases. Therefore, an efficiency improvement is necessary for IBC under light load to medium load conditions. This paper proposed an enhanced phase-shedding control algorithm using phase equivalent resistance estimation for a 3-ϕ IBC, aiming to improve efficiency across all load conditions by incorporating automatic phase selection. Also, in the case of phase number selection, the required unknown parameter value i.e. phase equivalent resistance has been measured online in order to improve phase shedding performance. In addition, this algorithm is implemented by including the auto change inner loop-average current mode control (ACIL-ACMC) to maintain equal current sharing among the phases and voltage regulation during load variation as well as phase switching. The overall phase shedding control has been developed in the DSP (TMS320F28335) for the designed 7.5kW IBC., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 ISA. Published by Elsevier Ltd. All rights reserved.)