3. Book Chapters
Permanent URI for this collectionhttps://idr.nitk.ac.in/handle/1/8
Browse
10 results
Search Results
Item Carbon Nanotubes and Graphene in Energy Storage and Catalysis(Studium Press LLC, USA, 2013) Rajarao, Ravindra; Bhat, Badekai RamachandraItem Zero-Dimensional Carbon Nanostructures for Supercapacitors(CRC Press, 2019) Mishra, Praveen; Bhat, Badekai RamachandraThe dependence of civilization on energy is rapidly increasing as the decades pass by. The world is now striving to find new sources to harness energy to meet this ever-increasing demand. This demand prompts research on energy generation and, more importantly, on energy storage devices. The latter has a high demand owing to the boom in the use of personal and portable electronic devices. Batteries have been catering to this requirement for quite some time now. Supercapacitors are the upcoming energy storing devices that can replace batteries due to their higher power output and fast recharge (Winter and Brodd 2004). A supercapacitor or an electrochemical capacitor is a simple device that can store charge at the interface of an electrode and an electrolyte (Kötz and Carlen 2000, Frackowiak and Béguin 2001). They are considered to be advantageous over batteries due to their very high specific capacitance, high power density, maintenance-free operations, no memory effect, and tapping into the massive void between the power-energy difference between capacitors and batteries.Item Correlation between Synthesis and Properties of Graphene(Materials Research Forum LLC, 2020) Mishra, Praveen; Bhat, Badekai RamachandraItem Microbes and their products as sensors in industrially important fermentations(2018) Raval R.; Raval K.This chapter details on the different microbial sensors used in fermentations. It takes through the path in history dealing with the developments made in devicing various sensors and their applications in as industrially important products. The chapter is designed to re-analyze the previous studies that covered the usage of whole cell and products of microbes as important parameters to improve the fermentation processes. © 2019 John Wiley & Sons Ltd. All rights reserved.Item Fuzzy-logic-based reactive power and voltage control in grid-connected wind farms to improve steady state voltage stability(2018) Moger T.; Dhadbanjan T.This chapter presents a fuzzy logic approach for reactive power and voltage control in grid-connected wind farms with different types of wind generator units to improve steady state voltage stability of power systems. The load buses' voltage deviation is minimized by changing the reactive power controllers according to their sensitivity using fuzzy set theory. The proposed approach uses only a few high sensitivity controllers to achieve the desired objectives. A 297-bus-equivalent grid-connected wind system and a 417-bus-equivalent grid-connected wind system are considered to present the simulation results. To prove the effectiveness of the proposed approach, a comparative analysis is also carried out with the conventional linear-programming-based reactive power optimization technique. Results demonstrated that the proposed approach is more effective in improving the system performance as compared with the conventional existing techniques. © 2018, IGI Global.Item Identification and Control of an Unstable SOPTD system with positive zero(2018) Dhanya Ram V.; Sankar Rao C.The work deals with the identification and control of unstable Second Order plus Time Delay (SOPTD) system with positive zero. Presence of positive zero complicates the performance of the control system dynamics. There are many unstable systems which exhibit the second order plus time delay with positive zero such as drum boiler, distillation column. No work has been reported in the literature on identification of unstable SOPTD process with positive zero. In this work, a subspace based method and an optimization method are proposed to identify an unstable SOPTD model with positive zero followed by the PID controller design which can handle set-point changes and disturbance rejection. The subspace-based method uses input-output measurements to estimate the state space model. This method uses projections of block Hankel matrices followed by a singular value decomposition to determine the order of the system. It offers the key advantages on providing low parameter sensitivity with respect to perturbations for higher order systems. The model parameters are also identified using optimization technique by matching the closed loop responses of the process and the model. In any optimization technique, the initial guess plays an important role for proper convergence. A method is suggested to obtain the initial guess values for process gain, poles, zeros and delay. The parameters identified by subspace based method are compared with that obtained using optimization technique. For the models identified by the above two methods, controllers are designed and implemented. Simulation studies on linear and nonlinear systems are demonstrated to evaluate the performance of the proposed methodologies. The closed loop performances comparison can be made in terms of time integral errors and total variation in input variable. © 2018 Elsevier B.V.Item Classification of cardiac abnormalities using heart rate signals: A comparative study(2007) Acharya U.R.; Kannathal N.; Bhat P.S.; Suri J.S.; Min L.C.; Spaan J.A.E.[No abstract available]Item Visualization of cardiac health using electrocardiograms(2007) Acharya U.R.; Bhat P.S.; Niranjan U.C.; Kannathal N.; Min L.C.; Suri J.S.The chapter discusses an efficient and novel method to assist the physician to visualize voluminous cardiac data acquired over several hours. The system uses different colors to identify different types of cardiogram signals. In the display strategy each ECG beat is represented by a grid. The visualization strategy is hierarchical; that is, it provides for viewing of data from different level of abstraction, and the physician can have a top down approach to narrow down the time interval and signal details. This display strategy is extended to sector graph, with a menu driven hierarchical display strategy, which progressively unfolds greater details for chosen intervals. Provision is made for changing the parameters of classification, and thus the physician has the option for fine tuning the classification. © Springer-Verlag Berlin Heidelberg 2007.Item Storage and transmission of cardiac data with medical images(2007) Acharya U.R.; Bhat P.S.; Niranjan U.C.; Kumar S.; Kannathal N.; Min L.C.; Suri J.S.The landscape of healthcare delivery and medical data management has significantly changed over the last years, as a result of the significant advancements in information and communication technologies. Complementary and/or alternative solutions are needed to meet the new challenges, especially regarding security of the widely distributed sensitive medical information. Digital watermarking is a technique of hiding specific identification data for copyright authentication. The DICOM standard is one method to include demographic information, such as patient information and X-ray exposure facilities, in image data. The DICOM standard is a standard that can be used regularly to record demographic information onto the image data header section. Regarding DICOM format images, information on patients and X-ray exposure facilities can be obtained easily from them. On the other hand, general-purpose image formats, such as the JPEG format, offer no standard that can be used regularly to record demographic information onto the header section. Digital watermark technologies [1-8] can be used to embed demographic information in image data. Digital watermarking have several other uses, such as fingerprinting, authentication, integrity verification purposes, content labeling, usage control and content protection [9, 10]. The efficient utilization of bandwidth of communication channel and storage space can be achieved, when the reduction in data size is done. Recently, Giakoumaki et al, have presented a review of research in the area of medical-oriented watermarking and proposed a wavelet-based multiple watermarking scheme. This scheme aimed to address critical health information management issues, including origin and data authentication, protection of sensitive data, and image archiving and retrieval [11]. Their experimental results on different medical imaging modalities demonstrated the efficiency and transparency of the watermarking scheme. The digital watermarking technique is adapted in this chapter for interleaving patient information with medical images, to reduce storage and transmission overheads. The text data is encrypted before interleaving with images to ensure greater security. The graphical signals are compressed and subsequently interleaved with the image. Differential pulse code modulation and adaptive delta modulation techniques are employed for data compression as well as encryption and results are tabulated for a specific example. Adverse effects of channel induced random errors and burst errors on the text data are countered by employing repetition code, Hamming code and R-S code techniques.Item Reef-an ecofriendly and cost effective hard option for coastal conservation(2008) Shirlal K.G.; Rao S.; Radheshyam B.; Ganesh V.Rubble mound breakwaters are the structures which are meant to reflect and dissipate energy of the wind generated waves and thereby to prevent their incidence on water area intended to protect. Submerged breakwater with its crest at or below still water level (SWL) can cause substantial wave attenuation and can be effectively used in places where tidal variations are small and only partial protection from waves is required, like harbour entrance, beach protection, small craft harbours etc. © 2008 Springer Netherlands.