Solution for a semi-infinite plate with radial crack and radial crack emanating from circular hole under bi-axial loading by body force method

Manjunath, B.S.,Ramakrishna, D.S. Techno-Press 2009 Interaction and multiscale mechanics Vol.2 No.2

Machine or structural members subjected to fatigue loading will have a crack initiated during early part of their life. Therefore analysis of members with cracks and other discontinuities is very important. Finite element method has enjoyed widespread use in engineering, but it is not convenient for crack problems as the region very close to crack tip is to be discretized with very fine mesh. However, as the body force method (BFM), requires only the boundary of the discontinuity (crack or hole) to be discretized it is easy versatile technique to analyze such problems. In the present work fundamental solution for concentrated load x + iy acting in the semi-infinite plate at an arbitrary point $z_0=x_0+iy_0$ is considered. These fundamental solutions are in complex form ${\phi}(z)$ and ${\psi}(z)$ (England 1971). These potentials are known as Melan potentials (Ramakrishna 1994). A crack in the semi-infinite plate as shown in Fig. 1 is considered. This crack is divided into number of divisions. By applying pair of body forces on a division, the resultant forces on the remaining 'N'divisions are to be found for which ${\phi}_1(z)$ and ${\psi}_1(z)$ are derived. Body force method is applied to calculate stress intensity factor for crack in semi-infinite plate. Also for the case of crack emanating from circular hole in semi-infinite plate radial stress, hoop stress and shear stress are calculated around the hole and crack. Convergent results are obtained by body force method. These results are compared with FEM results.

Feasibility of Computed Tomography Colonography as a Diagnostic Procedure in Colon Cancer Screening in India

Manjunath, Kanabagatte Nanjundappa,Gopalakrishna, Prabhu Karkala,Siddalingaswamy, Puttappa Chandrappa Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.13

Computed Tomography Colonography (CTC) is a medical imaging technology used in identifying polyps and colon cancer masses in the large intestine. The technique has evolved a great deal since its invention and has become a routine diagnostic procedure in Western countries due to its non invasiveness and ease of use. The objective of our study was to explore the possibility of CTC application in Indian hospitals. This paper gives an overview of the procedure and its commercial viability. The explanation begins with the domain aspects from gastroenterologist perspective, the new way of thinking in polyp classification, the technical components of CTC procedure, and how engineering solutions have helped clinicians in solving the complexities involved in colon diagnosis. The colon cancer statistics in India and the results of single institution study we carried out with retrospective data is explained. By considering the increasing number of patients developing colon malignancies, the practicality of CTC in Indian hospitals is discussed. This paper does not reveal any technical aspects (algorithms) of engineering solutions implemented in CTC.

Modeling and fast output sampling feedback control of a smart Timoshenko cantilever beam

Manjunath, T. C.,Bandyopadhyay, B. Techno-Press 2005 Smart Structures and Systems, An International Jou Vol.1 No.3

This paper features about the modeling and design of a fast output sampling feedback controller for a smart Timoshenko beam system for a SISO case by considering the first 3 vibratory modes. The beam structure is modeled in state space form using FEM technique and the Timoshenko beam theory by dividing the beam into 4 finite elements and placing the piezoelectric sensor/actuator at one location as a collocated pair, i.e., as surface mounted sensor/actuator, say, at FE position 2. State space models are developed for various aspect ratios by considering the shear effects and the axial displacements. The effects of changing the aspect ratio on the master structure is observed and the performance of the designed FOS controller on the beam system is evaluated for vibration control.

Automatic Electronic Cleansing in Computed Tomography Colonography Images using Domain Knowledge

Manjunath, KN,Siddalingaswamy, PC,Prabhu, GK Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.18

Electronic cleansing is an image post processing technique in which the tagged colonic content is subtracted from colon using CTC images. There are post processing artefacts, like: 1) soft tissue degradation; 2) incomplete cleansing; 3) misclassification of polyp due to pseudo enhanced voxels; and 4) pseudo soft tissue structures. The objective of the study was to subtract the tagged colonic content without losing the soft tissue structures. This paper proposes a novel adaptive method to solve the first three problems using a multi-step algorithm. It uses a new edge model-based method which involves colon segmentation, priori information of Hounsfield units (HU) of different colonic contents at specific tube voltages, subtracting the tagging materials, restoring the soft tissue structures based on selective HU, removing boundary between air-contrast, and applying a filter to clean minute particles due to improperly tagged endoluminal fluids which appear as noise. The main finding of the study was submerged soft tissue structures were absolutely preserved and the pseudo enhanced intensities were corrected without any artifact. The method was implemented with multithreading for parallel processing in a high performance computer. The technique was applied on a fecal tagged dataset (30 patients) where the tagging agent was not completely removed from colon. The results were then qualitatively validated by radiologists for any image processing artifacts.

TLSA: A Two Level Scheduling Algorithm for Multiple packets Arrival in TSCH Networks

( Manjunath G. Asuti ),( Prabhugoud I. Basarkod ) 한국인터넷정보학회 2020 KSII Transactions on Internet and Information Syst Vol.14 No.8

Wireless communication has become the promising technology in the recent times because of its applications in Internet of Things( IoT) devices. The IEEE 802.15.4e has become the key technology for IoT devices which utilizes the Time-Slotted Channel Hopping (TSCH) networks for the communication between the devices. In this paper, we develop a Two Level Scheduling Algorithm (TLSA) for scheduling multiple packets with different arrival rate at the source nodes in a TSCH networks based on the link activated by a centralized scheduler. TLSA is developed by considering three types of links in a network such as link i with packets arrival type 1, link j with packets arrival type 2, link k with packets arrival type 3. For the data packets arrival, two stages in a network is considered. At the first stage, the packets are considered to be of higher priority. At the second stage, the packets are considered to be of lower priority. We introduce level 1 schedule for the packets at stage 1 and level 2 schedule for the packets at stage 2 respectively. Finally, the TLSA is validated with the two different energy functions i.e., y=e^ax -1 and y=0.5x² using MATLAB 2017a software for the computation of average and worst ratios of the two levels.

Electrical and frequency-dependent properties of Au/Sm2O3/n-GaN MIS junction with a high-k rare-earth Sm2O3 as interlayer

V. Manjunath,V. Rajagopal Reddy,P.R. Sekhar Reddy,V. Janardhanam,최철종 한국물리학회 2017 Current Applied Physics Vol.17 No.7

High-k rare-earth samarium oxide (Sm2O3) films are formed on n-GaN surface and analyzed its compositional properties by XPS measurements. XPS results specify that the Sm2O3 films are formed at the interface. Then, the Au/Sm2O3/n-GaN MIS junction is prepared with a Sm2O3 as insulating layer and correlated its electrical properties with the Au/n-GaN MS junction. The MIS junction shows highest barrier height ((0.81 eV (I-V)/1.0 eV (C-V)) for MIS junction than the MS junction (0.68 eV (I-V)/0.90 eV (C-V)). Excellent rectifying property is observed with lowest reverse leakage current and higher barrier height for the MIS junction than the MS junction, implying that the Sm2O3 insulating layer effectively modified the barrier height. The barrier heights determined from I-V, Cheung's, Norde and JS eV plot closely matched with each other, suggesting that these techniques are reliable and valid. The estimated interface state density of the MIS junction (1.990 1011 cm2eV1 (EC-0.82 eV)) is lower than the MS junction (9.204 1012 cm2eV1 (EC-0.70 eV)), which demonstrates that the Sm2O3 insulating layer performs an important role in lowering the interface state density. The frequency-dependent characteristics of the MS and MIS junctions are discussed in the frequency range of 10 kHz to 1 MHz and found that the determined capacitance values decrease with increasing frequency. The forward I-V characteristic of the MS and MIS junctions reveals the ohmic behavior at low voltage regions and space-chargelimited conduction at higher voltage regions. Results reveal that the reverse leakage current in the studied MS and MIS junctions is controlled by a Poole-Frenkel emission.

S-Corona operations of standard graphs in terms of degree sequences

M. MANJUNATH,V. Lokesha 장전수학회 2020 Proceedings of the Jangjeon mathematical society Vol.23 No.2

Let G and H be two graphs with vertices n1 and n2 and edges e1 and e2 respectively. The corona of graphs G and H with disjoint vertex sets V (G) and V (H) and edge sets E(G) and E(H) is obtained by taking one copy of G and jV (G)j copies of H, by joining the ith vertex of V (G) to each vertex in the ith copy of H. The degree sequence (DS) of a graph is the set of vertex degrees. In this article, we determine the (DS) of S- vertex (edge) corona and S- edge neighbourhood corona operation of standard graphs.

Second law thermodynamic analysis of nanofluid turbulent flow in heat exchanger

K. Manjunath Techno-Press 2022 Advances in energy research Vol.8 No.3

Entropy generation along with exergetic analysis is carried out using turbulent nanofluid flow in the heat exchanger. To obtain the optimized percentage constituent of nanofluid, the nanofluid volume concentrations is varied for the given input conditions. For different Reynolds number of the fluid and heat capacity rate ratio between the streams, the heat transfer improvements are studied in terms of nano particles diameter. Parametric analysis is carried out for a counterflow heat exchanger using turbulent nanofluid flow with exergetic efficiency along with entropy generation number as performance parameters. The exergetic efficiency provides realistic approach in the design of nanofluid applications in heat exchanger leading to conservation of energy.

Multifunctional lipidic nanocarriers for effective therapy of glioblastoma: recent advances in stimuli-responsive, receptor and subcellular targeted approaches

Hegde Manasa Manjunath,Prabhu Suma,Mutalik Srinivas,Chatterjee Abhishek,Goda Jayant S.,Satish Rao B. S. 한국약제학회 2022 Journal of Pharmaceutical Investigation Vol.52 No.1

Background Glioblastoma, or glioblastoma multiforme (GBM), remains a fatal cancer type despite the remarkable progress in understanding the genesis and propagation of the tumor. Current treatment modalities, comprising mainly of surgery followed by adjuvant chemoradiation, are insufficient for improving patients' survival owing to existing hurdles, including the blood–brain barrier (BBB). In contemporary practice, the prospect of long-term survival or cure continues to be a challenge for patients suffering from GBM. This review provides an insight into the drug delivery strategies and the significant efforts made in lipid-based nanoplatform research to circumvent the challenges in optimal drug delivery in GBM. Area covered Owing to the unique properties of lipid-based nanoplatforms and advancements in clinical translation, this article describes the application of various stimuli-responsive lipid nanocarriers and tumor subcellular organelle-targeted therapy to give an idea about the strategies that can be applied to enhance site-specific drug delivery for GBM. Furthermore, active targeting of drugs via surface-modified lipid-based nanostructures and recent findings in alternative therapeutic platforms such as gene therapy, immunotherapy, and multimodal therapy have also been overviewed. Expert opinion Lipid-based nanoparticles stand out among the other nanocarriers explored for GBM drug delivery, as they support both passive and active drug targeting by crossing/bypassing the BBB at the same time minimizing toxicity and projects better pharmacological parameters. Although these nanocarriers could be a plausible choice for treating GBM, indepth research is essential to advance neuro-oncology research and enhance outcomes in patients with brain tumors.

Vibration Control of A Thin Walled Composite Beam Using PID Control Technique

T.C. Manjunath,IIT Bombay,Sheelarani T B,C B Vinutha,M Z Kurien 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8

This paper features the modeling and design of a PID controller to control the vibrations of a smart thin walled composite box beam. Collocated piezoelectric patches are bonded as sensor / actuator to the master structure at a certain finite element location on the beam, i.e., nearby the fixed end of the composite box beam. The beam structure is modeled in the state space form using the concept of piezoelectric theory, the Timoshenko beam theory and the Finite Element Method. The beam is subjected to an external disturbance (say, impulse or sine or random excitation). A novel PID controller is designed for the smart composite box beam. When the designed controller is put in the loop with the plant, i.e., the smart structure plant, the plant performs well and the vibrations are damped out in a quicker time. The performance of the designed controller is thus evaluated for vibration control and the conclusions are here by drawn. The simulation results show the effectiveness of the developed method. This is the main objective of this paper.