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Discrete Event System Framework for Fault Diagnosis with Measurement Inconsistency:Case Study of Rogue DHCP Attack

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IEEE/CAA Journal of Automatica Sinica 2019年第3期6卷 789-806页

作者： Mayank Agarwal Santosh Biswas Sukumar nandi IEEE the Department of Computer Science and Engineering Indian Institute of Technology Guwahati

Fault detection and diagnosis(FDD) facilitates reliable operation of systems. Various approaches have been proposed for FDD like Analytical redundancy(AR), Principal component analysis(PCA), Discrete event system(DES) model etc., in the literature. Performance of FDD schemes greatly depends on accuracy of the sensors which measure the system *** to various reasons like faults, communication errors etc.,sensors may occasionally miss or report erroneous values of some system parameters to FDD engine, resulting in measurement inconsistency of these parameters. Schemes like AR, PCA etc.,have mechanisms to handle measurement inconsistency, however,they are computationally heavy. DES based FDD techniques are widely used because of computational simplicity, but they cannot handle measurement inconsistency efficiently. Existing DES based schemes do not use Measurement inconsistent(MI)parameters for FDD. These parameters are not permanently unmeasurable or erroneous, so ignoring them may lead to weak diagnosis. To address this issue, we propose a Measurement inconsistent discrete event system(MIDES) framework, which uses MI parameters for FDD at the instances they are measured by the sensors. Otherwise, when they are unmeasurable or erroneously reported, the MIDES invokes an estimator diagnoser that predicts the state(s) the system is expected to be in, using the subsequent parameters measured by the other sensors. The efficacy of the proposed method is illustrated using a pumpvalve system. In addition, an MIDES based intrusion detection system has been developed for detection of rogue dynamic host configuration protocol(DHCP) server attack by mapping the attack to a fault in the DES framework.

关键词： Fault diagnosis instrasion detection system (IDS) measurement inconsistent discrete event system (DES) rogue dynamic host configuration protocol (DHCP) server

Connected Components-based Colour Image Representations of Vibrations for a Two-stage Fault Diagnosis of Roller Bearings Using Convolutional Neural Networks

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Chinese Journal of Mechanical Engineering 2021年第3期34卷 73-93页

作者： Hosameldin O.A.Ahmed Asoke K nandi Department of Electronic and Electrical Engineering Brunel University LondonUxbridge UB83PHUK School of Mechanical Engineering Xi’an Jiaotong UniversityXi’anChina

Roller bearing failure is one of the most common faults in rotating *** techniques for bearing fault diagnosis based on faults feature extraction have been *** feature extraction from fault signals requires expert prior information and human ***,deep learning algorithms have been applied extensively in the condition monitoring of rotating machines to learn features automatically from the input *** its robust performance in image recognition,the convolutional neural network(CNN)architecture has been widely used to learn automatically discriminative features from vibration images and classify health *** paper proposes and evaluates a two-stage method RGBVI-CNN for roller bearings fault *** first stage in the proposed method is to generate the RGB vibration images(RGBVIs)from the input vibration *** begin this process,first,the 1-D vibration signals were converted to 2-D grayscale vibration *** the conversion was completed,the regions of interest(ROI)were found in the converted 2-D grayscale vibration ***,to produce vibration images with more discriminative characteristics,an algorithm was applied to the 2-D grayscale vibration images to produce connected components-based RGB vibration images(RGBVIs)with sets of colours and texture *** the second stage,with these RGBVIs a CNN-based architecture was employed to learn automatically features from the RGBVIs and to classify bearing health *** cases of fault classification of rolling element bearings are used to validate the proposed *** results of this investigation demonstrate that RGBVI-CNN can generate advantageous health condition features from bearing vibration signals and classify the health conditions under different working loads with high ***,several classification models trained using RGBVI-CNN offered high performance in the testing results of the overall classification accura

关键词： Bearing fault diagnosis Image representation of vibrations Deep learning Convolutional neural networks

Intrusion Detection System for PS-Poll DoS Attack in 802.11 Networks Using Real Time Discrete Event System

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IEEE/CAA Journal of Automatica Sinica 2017年第4期4卷 792-808页

作者： Mayank Agarwal Sanketh Purwar Santosh Biswas Sukumar nandi IEEE Department of Computer Science and Engineering ⅡT Guwahati HP PPS R&D Lab in Bangalore

Wi-Fi devices have limited battery life because of which conserving battery life is imperative. The 802.11 Wi-Fi standard provides power management feature that allows stations(STAs) to enter into sleep state to preserve energy without any frame losses. After the STA wakes up, it sends a null data or PS-Poll frame to retrieve frame(s) buffered by the access point(AP), if any during its sleep period. An attacker can launch a power save denial of service(PS-DoS) attack on the sleeping STA(s) by transmitting a spoofed null data or PS-Poll frame(s) to retrieve the buffered frame(s) of the sleeping STA(s) from the AP causing frame losses for the targeted STA(s). Current approaches to prevent or detect the PS-DoS attack require encryption,change in protocol or installation of proprietary hardware. These solutions suffer from expensive setup, maintenance, scalability and deployment issues. The PS-DoS attack does not differ in semantics or statistics under normal and attack *** signature and anomaly based intrusion detection system(IDS) are unfit to detect the PS-DoS attack. In this paper we propose a timed IDS based on real time discrete event system(RTDES) for detecting PS-DoS attack. The proposed DES based IDS overcomes the drawbacks of existing systems and detects the PS-DoS attack with high accuracy and detection rate. The correctness of the RTDES based IDS is proved by experimenting all possible attack scenarios.

关键词： Fault detection and diagnosis intrusion detection system(IDS) null data frame power save attack PS-Poll frame real time discrete event system(DES)

Combustion characteristics of high ash Indian thermal,heat affected coal and their blends

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International Journal of Coal Science & Technology 2021年第5期8卷 1078-1087页

作者： Subhajit Aich Barun Kumar nandi Sumantra Bhattacharya Department of Fuel Minerals and Metallurgical Engineering Indian Institute of Technology(Indian School of Mines)Dhanbad 826004JharkhandIndia

Onsite mine fire generates large volumes of heat-affected coal in Jharia coalfields,*** utilization of such heat-affected coal in thermal utilities is not feasible as such coal does not have the desirable volatile matter required for *** the present work,experimental studies have been carried out to investigate the possible utilization of such heat-affected coal in thermal utilities by blending with other ***-affected coal(31%ash and 5300 kcal/kg GCV)collected from Jharia coalfield were blended with thermal coal(28%ash and 5650 kcal/kg GCV)in different ratios of 90:10,80:20,70:30 and 60:40 to identify the desirable blend ratio for burning of blended coal in thermal *** characteristics of all the coals were carried out using *** combustion parameters such as ignition temperature,peak temperature,burnout temperature,ignition index,burnout index,combustion performance index,rate and heat intensity index of the combustion process and activation energy were evaluated to analyse the combustion *** and theoretical analysis shows the blend ratio of 90:10 can be used in place of only thermal coal in utilities to reduce the fuel cost.

关键词： Coal blends Heat affected coal Combustion indices TGA-DTG Burning profile Mass gain analysis

Effects of Main-chain and Chain-ends on the Organogelation of Stearoyl Appended Pendant Valine Based Polymers

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Chinese Journal of Polymer Science 2019年第9期37卷 903-911页

作者： Mridula nandi Swagata Pan Dipannita Ghosh Priyadarsi De Polymer Research Centre and Centre for Advanced Functional Materials Department of Chemical Sciences Indian Institute of Science Education and Research Kolkata

In this work, we investigated the effect of hydrophobic interactions between the polymeric backbone and chain-end groups on the self-assembly pathway of stearoyl appended side-chain valine（Val）-based poly（methacrylate/acrylate） homopolymers in different organic hydrocarbons. Gelation studies conducted revealed that while polymers with polyacrylate as backbone induces gelation in several organic hydrocarbons, polymers with polymethacrylate in the main-chain significantly hinders macroscopic gelation. Morphology of the organogels was analysed by field emission scanning electron microscopy（FESEM）, and mechanical strengths of the organogels were determined by rheological measurements. Reversible addition-fragmentation chain transfer（RAFT） polymerization chain transfer agents（CTA）s, [R1―S―C=（S）―S―R2] with different ―R1 and ―R2 groups, have been employed to study the effect of structural variation at the chain-end on macroscopic assembly mechanism. We found that the additional interactions between terminal groups via hydrogenbonding or π-π stacking interactions or both help to build up the self-assembly pathway and thereby produces mechanically stable organogels.

关键词： Organogelation Hydrophobic interactions Poly(methacrylate/acrylate) backbone RAFT polymerization Self-assembly

Electric discharge phenomenon in dielectric and electrolyte medium

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Advances in Manufacturing 2018年第4期6卷 457-464页

作者： Mukesh Kumar Sindhu Debasish nandi Indrajit Basak Department of Mechanical Engineering. NIT Durgapur. Durgapur 713209. India Department of Mechanical Engineering JIS College of Engineering Kalyani 741235 India

Electric discharge is a common tool nowadays for machining of materials. It may be through a liquid medium or through air. Any metals, hard alloys, and nonmetals can be machined using the energy of electric discharge. In electric discharge machining (EDM), the discharge occurs between two electrodes through a liquid medium and it is applicable only for electrically con ducting materials and alloys. In electrochemical discharge machining (ECDM), the medium is an aqueous electrolyte and it is of two types. In the first type, the discharge occurs between two electrodes. One of the electrodes is the workpiece, and the other is the tool. In the second type, the discharge occurs between one electrode and an electrolyte. It is used for electrically nonconducting materials and the discharge energy is utilized maintaining the nonconducting workpiece in proximity of the discharge. All these electrical discharges are transient phenomena and do not result in a stable discharge in the form of arc. The output parameters depend on the discharge energy that requires precise control to maintain the accuracy of the machining. For micromachining, the control of the discharge is paramount both in terms of energy and pattern. Using various shaped tools, machining media with additives, different types of applied potentials, and supporting mechanical motions are some of the attempts made to improve the machining output. Optimization of these parameters for machining particular materials (or alloys) is a popular field of research. The present work is directed toward the investigation of discharge initiation and development by analyzing the cell current and discharge voltage relationship for both EDM and ECDM. The rectangular direct current (DC) pulse with different frequencies and the duty factor (on-off time ratio) are used for investigation. Observations on the voltage-current relationship are made for the external potential prior to discharge at discharge and above the discharge potenti

关键词： Electric discharge Electric discharge machining (EDM) Electrochemical discharge machining (ECDM) Pulsed direct current (DC) Duty factor

A generic method for rock mass classification

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第1期10卷 102-116页

作者： Vitthal M.Khatik Arup Kr.nandi Department of Mechanical Engineering Indian Institute of TechnologyKanpur208016India Engineering Design Group CSIR-Central Mechanical Engineering Research InstituteMG AvenueDurgapur713209India

Rock mass classification(RMC) is of critical importance in support design and applications to mining,tunneling and other underground excavations. Although a number of techniques are available, there exists an uncertainty in application to complex underground works. In the present work, a generic rock mass rating(GRMR) system is developed. The proposed GRMR system refers to as most commonly used techniques, and two rock load equations are suggested in terms of GRMR, which are based on the fact that whether all the rock parameters considered by the system have an influence or only few of them are influencing. The GRMR method has been validated with the data obtained from three underground coal mines in India. Then, a semi-empirical model is developed for the GRMR method using artificial neural network(ANN), and it is validated by a comparative analysis of ANN model results with that by analytical GRMR method.

关键词： Rock mass classification(RMC) Generic system Rock load Mathematical model Artificial neural network(ANN)

In vitro and in vivo degradability,biocompatibility and antimicrobial characteristics of Cu added iron-manganese alloy

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Journal of Materials Science & Technology 2021年第25期84卷 159-172页

作者： Santanu Mandal Vijay Kishore Madhuparna Bose Samit Kumar nandi Mangal Ro Department of Metallurgical and Materials Engineering Indian Institute of Technology-KharagpurKharagpur 721302India Department of Veterinary Surgery&Radiology West Bengal University of Animal&Fishery SciencesKolkata 700037India Department of Biotechnology Indian Institute of TechnologyKharagpur 721302India

In recent years,iron(Fe)based degradable metal is explored as an alternative to permanent fracture fixation *** the present work,copper(Cu)is added in Fe-Mn system to enhance the degradation rate and antimicrobial ***-Mn-x Cu(x=0.9,5 and 10 wt.%)alloys are prepared by the meltingcasting-forging *** analysis confirms austenite phase stabilization due to the presence of Mn and *** predicted by Thermo-Calc calculations,Cu rich phase precipitations are noticed along the austenite grain *** behaviours of Cu added Fe-Mn alloys are investigated through static immersion and electrochemical polarization where enhanced degradation is found for higher Cu added *** challenged against *** bacteria,the Fe-Mn-Cu alloy media extract shows a significant bactericidal effect compare to the base *** vitro cytocompatibility studies,as determined using MG63 and MC3T3-E1 cell lines,indicate increased cell density as a function of time for all the *** implanted in rabbit femur,the newly developed alloy does not show any kind of tissue necrosis around the *** osteogenesis and higher new bone formation are observed with Fe-Mn-10 Cu alloy as evident from micro-computed tomography(μ-CT)and fluorochrome labelling.

关键词： Iron-manganese alloy Degradable metal In vitro Micro-CT

Effect of weathering on physico-chemical properties and combustion behavior of an Indian thermal coal

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International Journal of Coal Science & Technology 2019年第1期6卷 51-62页

作者： Subhajit Aich Barun Kumar nandi Sumantra Bhattacharya Department of Fuel and Mineral Engineering Indian Institute of Technology (Indian School of Mines)Dhanbad Dhanbad Jharkhand 826004India

An open air stockpile of conical shape was formed with 3.5 m base diameter and 5 m height using 500 tons of -200 mm size ROM thermal coal on a concrete floor. Coal sample from the stockpile were collected at 30 days interval for analysis of various chemical properties like;proximate analysis, ultimate analysis, gross calorific value (GCV) and various combustion related properties such as ignition temperature, peak temperature, burnout temperature, maximum combustion rate, ignition index, burnout index, combustion performance index and combustion rate intensity index. Experimental results show that, due to weathering of coal fixed carbon decreased from 35.6% to 19.9%, elemental carb on (C) decreased from 46.6% to 28.6%, hydrogen (H) decreased from 3.3% to 2.9% and GCV decreased by up to 55% of original value during 330 days of storage of coal in an open atmosphere. Ash con tent of coal increased form 29.2% to 46.6% due to loss of combustibles. Sulfur (S) of coal was found to get increased from 0.33% to 1.08% during storage. The activation energy of coal combustion increased from 22 kJ/mol to 54 kJ/mol. Variation in combustion parameters signifies that weathering has significant negative impact on coal combustion properties as coal become difficult to ignite.

关键词： Weathering of coal TGA-DTG Combustibles Coal combustion Activation energy