Multiscale Modeling of Swelling Clays: A Computational and Experimental Approach

Dinesh R. Katti,Mohamed I. Matar,Kalpana S. Katti,Priyanthi M. Amarasinghe 대한토목학회 2009 KSCE Journal of Civil Engineering Vol.13 No.4

Expansive clays such as montmorillonite cause severe distress to infrastructure due to swelling. The swelling of montmorillonite clay is also the basis for its use in many commercial applications such as drilling muds in petroleum engineering, as landfill liners in environmental engineering and in making polymer clay nanocomposites. The focus of this work is to carry out a systematic experimental and numerical study to understand and model behavior of Na-montmorillonite at molecular and particulate level to find mechanism of swelling in the Na-montmorillonite interlayer. Experimental results show breakdown of particles with an increase in swelling of the clay. This phenomenon was numerically studied by developing a modified Discrete Element Method (DEM) model that incorporates the latest developments in both clay and computer science, and can simulate particle subdivision. DEM results show the role of particle subdivision on swelling and swelling pressure. In understanding the true mechanism of swelling, it is essential to incorporate the interactions between clay molecular structure and the interlayer water molecules. For bridging the length scales, we have also evaluated the stress deformation response of the clay molecular structure using Molecular Dynamic (MD) simulations. Simulation results show that the deformation in the clay molecular structure due to external stress is mostly due to deformation of the water molecules in the clay interlayer. A new experimental technique which enables us to capture the molecular changes in the clay molecular structure upon hydration is also developed. This work provides a foundation for multiscale modeling of swelling clays. Expansive clays such as montmorillonite cause severe distress to infrastructure due to swelling. The swelling of montmorillonite clay is also the basis for its use in many commercial applications such as drilling muds in petroleum engineering, as landfill liners in environmental engineering and in making polymer clay nanocomposites. The focus of this work is to carry out a systematic experimental and numerical study to understand and model behavior of Na-montmorillonite at molecular and particulate level to find mechanism of swelling in the Na-montmorillonite interlayer. Experimental results show breakdown of particles with an increase in swelling of the clay. This phenomenon was numerically studied by developing a modified Discrete Element Method (DEM) model that incorporates the latest developments in both clay and computer science, and can simulate particle subdivision. DEM results show the role of particle subdivision on swelling and swelling pressure. In understanding the true mechanism of swelling, it is essential to incorporate the interactions between clay molecular structure and the interlayer water molecules. For bridging the length scales, we have also evaluated the stress deformation response of the clay molecular structure using Molecular Dynamic (MD) simulations. Simulation results show that the deformation in the clay molecular structure due to external stress is mostly due to deformation of the water molecules in the clay interlayer. A new experimental technique which enables us to capture the molecular changes in the clay molecular structure upon hydration is also developed. This work provides a foundation for multiscale modeling of swelling clays.

Band Selection Using Forward Feature Selection Algorithm for Citrus Huanglongbing Disease Detection

Katti, Anurag R.,Lee, W.S.,Ehsani, R.,Yang, C. Korean Society for Agricultural Machinery 2015 바이오시스템공학 Vol.40 No.4

Purpose: This study investigated different band selection methods to classify spectrally similar data - obtained from aerial images of healthy citrus canopies and citrus greening disease (Huanglongbing or HLB) infected canopies - using small differences without unmixing endmember components and therefore without the need for an endmember library. However, large number of hyperspectral bands has high redundancy which had to be reduced through band selection. The objective, therefore, was to first select the best set of bands and then detect citrus Huanglongbing infected canopies using these bands in aerial hyperspectral images. Methods: The forward feature selection algorithm (FFSA) was chosen for band selection. The selected bands were used for identifying HLB infected pixels using various classifiers such as K nearest neighbor (KNN), support vector machine (SVM), naïve Bayesian classifier (NBC), and generalized local discriminant bases (LDB). All bands were also utilized to compare results. Results: It was determined that a few well-chosen bands yielded much better results than when all bands were chosen, and brought the classification results on par with standard hyperspectral classification techniques such as spectral angle mapper (SAM) and mixture tuned matched filtering (MTMF). Median detection accuracies ranged from 66-80%, which showed great potential toward rapid detection of the disease. Conclusions: Among the methods investigated, a support vector machine classifier combined with the forward feature selection algorithm yielded the best results.

Band Selection Using Forward Feature Selection Algorithm for Citrus Huanglongbing Disease Detection

( Anurag R. Katti ),( W. S. Lee ),( R. Ehsani ),( C. Yang ) 한국농업기계학회 2015 바이오시스템공학 Vol.40 No.4

Purpose: This study investigated different band selection methods to classify spectrally similar data - obtained from aerial images of healthy citrus canopies and citrus greening disease (Huanglongbing or HLB) infected canopies - using small differences without unmixing endmember components and therefore without the need for an endmember library. However, large number of hyperspectral bands has high redundancy which had to be reduced through band selection. The objective, therefore, was to first select the best set of bands and then detect citrus Huanglongbing infected canopies using these bands in aerial hyperspectral images. Methods: The forward feature selection algorithm (FFSA) was chosen for band selection. The selected bands were used for identifying HLB infected pixels using various classifiers such as K nearest neighbor (KNN), support vector machine (SVM), naive Bayesian classifier (NBC), and generalized local discriminant bases (LDB). All bands were also utilized to compare results. Results: It was determined that a few well-chosen bands yielded much better results than when all bands were chosen, and brought the classification results on par with standard hyperspectral classification techniques such as spectral angle mapper (SAM) and mixture tuned matched filtering (MTMF). Median detection accuracies ranged from 66-80%, which showed great potential toward rapid detection of the disease. Conclusions: Among the methods investigated, a support vector machine classifier combined with the forward feature selection algorithm yielded the best results.

Static Task Scheduling Algorithm with Minimum Distance for Multiprocessor System (STMD)

Ranjit Rajak,C.P.Katti 한국산학기술학회 2015 SmartCR Vol.5 No.2

Task scheduling in the multiprocessor environment is considered to be a NP-complete problem. It is also called a multiprocessor scheduling. Here, a parallel program is divided into a number of subtasks and it is mapped on the processors for concurrent execution. The objective of task scheduling is to reduce scheduling length of a given application program. Considering that task scheduling is represented by Directed Acyclic Grape (DAG). There are two types of task scheduling algorithms: static task scheduling and dynamic task scheduling algorithms. In this paper, we propose a new task scheduling algorithm based on minimum distance and an entry task duplicated on the processors. The minimum distance computes between an entry task and its successors. It includes, minimum distance of parent task, execution time and communication time Here , also considering a priority list (PL) attribute that contains tasks information of a given application program whose distance is minimum from an entry task. Finally, we will do comparative study of the proposed algorithm with Bounded Number of Processors (BNP) class of scheduling algorithms. It has done based on the following matrices: Scheduling Length, Speedup, Efficiency, Load Balancing and Normalized Scheduling Length (NSL). It showed proposed algorithm gives better result than BNP class of scheduling algorithms.

Effect of Different Periods of Cold Storing of Bivoltine Eggs on Subsequent Generation Rearing Performance

Venkatesh, H.,Raghuraman, R.,Katti, S.R. Korean Society of Sericultural Science 2004 International Journal of Industrial Entomology Vol.9 No.2

Different methods of cold storing of bivoltine eggs are in practice to postpone hatching. Bivoltine eggs undergo hibernation if they are not acid treated within 20 - 24 hrs of oviposition, which depends on race, ambient temperature and humidity. The schedules adopted for cold storing include hibernation schedule (Hib), ordinary chilling (OC), short term chilling (STC) and acid treated layings (AT). Peanut cocooning race ${NB_4}{D_2}$ has been subjected for the present assessment. Cocoons harvested from the crop pertaining to all the four methods of cold storing have been used for producing different combinations and acid treated followed by rearing. The performance in respect of chawki loss, maximum larval weight 4({5^th} age)$, yield/ 10,000 larvae (no), cocoon and shell weight showed maximum values for hibernation ${\times}$ hibernation combination followed hibernation with OC and hibernation with AT. Lowest performance was recorded when STC batch source females were used.

DAMPING TECHNOLOGY AND MATERIALS

Mr. Ravindra S. Birajdar,Uday M Katti 한국소음진동공학회 2008 한국소음진동공학회 국제학술대회논문집 Vol.2008 No.7

Study of Cloud Computing and its Issues: A Review

J. K. Verma,C. P. Katti 한국산학기술학회 2014 SmartCR Vol.4 No.5

Cloud computing is a new paradigm for hosting and delivering services using the standard protocols of the Internet. It refers to a service-oriented architecture that offers ubiquitous and convenient computing, greater flexibility, on-demand services, reduced total cost of ownership, reduced information technology overhead for the end-user, and many other things. It allows access to a large amount of computing power in a fully virtualized mode by aggregating a configurable pool of resources that are rapidly provisioned and released dynamically. It also provides the capability to utilize scalable, distributed computing environments within the confines of the Internet with minimal management effort while keeping a single coherent system view. Cloud computing is constantly gaining popularity in the information technology industry, and so more and more issues and challenges are emerging that need to be handled for the success of this paradigm. This paper presents an introduction of cloud computing, and a comparative study of cloud computing and grids. Furthermore, we put forward pinpoint research issues in the cloud computing paradigm and a mathematical understanding of several issues among them.

Notes : Effect of Different Periods of Cold Storing of Bivoltine Eggs on Subsequent Generation Rearing Performance

( H. Venkatesh ),( R. Raghuraman ),( S. R. Katti ) 한국잠사학회 2004 International Journal of Industrial Entomology Vol.9 No.2

Concordance between preoperative ESMO-ESGO-ESTRO risk classification and final histology in early-stage endometrial cancer

Manon Daix,Martina Aida Angeles,Federico Migliorelli,Athanasios Kakkos,Carlos Martinez Gomez,Katty Delbecque,Eliane Mery,Stéphanie Tock,Erwan Gabiache,Marjolein Decuypere,Frédéric Goffin,Alejandra Mar 대한부인종양학회 2021 Journal of Gynecologic Oncology Vol.32 No.4

Objective: To evaluate the concordance between preoperative European Society for Medical Oncology (ESMO)-European Society of Gynaecological Oncology (ESGO)-European SocieTy for Radiotherapy and Oncology (ESTRO) risk classification in early-stage endometrial cancer (EC) assessed by biopsy and magnetic resonance imaging (MRI) with this classification based on histology of surgical specimen. Methods: This bicentric retrospective study included women diagnosed with early-stage EC (≤stage II) who had a complete preoperative assessment and underwent a surgical management from January 2011 to December 2018. Patients were preoperatively classified into 3 degrees of risk of lymph node (LN) involvement based on biopsy and MRI. Based on final histological report, patients were re-classified using the preoperative classification. Concordance between the preoperative assessment and definitive histology was calculated with weighted Cohen's kappa coefficient. Results: A total of 333 women were included and kappa coefficient of preoperative risk classification was 0.49. The risk was underestimated and overestimated in 37% and 10% of cases, respectively. Twenty-nine percent of patients had an incomplete LN staging according to the degree of risk of re-classification. The observed discordance in the risk classification was attributed to MRI in 75% of cases, to biopsy in 18% and in 7% to both (p<0.001). Kappa coefficient for concordance was 0.25 for MRI and 0.73 for biopsy. Conclusion: Concordance between preoperative ESMO-ESGO-ESTRO risk classification and final histology is weak. Given that the risk was underestimated in the majority of patients wrongly classified, sentinel LN procedure instead of no LN dissection could be an option offered to preoperative low-risk patients to decrease the indication of second surgery for re- staging and/or to avoid toxicity of adjuvant radiotherapy.

Prophylactic and Therapeutic Potential of Asp f1 Epitopes in Naive and Sensitized BALB/c Mice

Chaudhary, Neelkamal,Mahajan, Lakshna,Madan, Taruna,Kumar, Anil,Raghava, Gajendra Pratap Singh,Katti, Seturam Bandacharya,Haq, Wahajul,Sarma, Puranam Usha The Korean Association of Immunobiologists 2009 Immune Network Vol.9 No.5

Background: The present study examines a hypothesis that short allergen-derived peptides may shift an Aspergillus fumigatus (Afu-) specific TH2 response towards a protective TH1. Five overlapping peptides (P1-P5) derived from Asp f1, a major allergen/antigen of Afu, were evaluated for prophylactic or therapeutic efficacy in BALB/c mice. Methods: To evaluate the prophylactic efficacy, peptides were intranasally administered to naive mice and challenged with Afu-allergens/antigens. For evaluation of therapeutic efficacy, the mice were sensitized with Afu-allergens/antigens followed by intranasal administration of peptides. The groups were compared for the levels of Afu-specific antibodies in sera and splenic cytokines evaluated by ELISA. Eosinophil peroxidase activity was examined in the lung cell suspensions and lung inflammation was assessed by histopathogy. Results: Peptides P1-, P2- and P3 decreased Afu-specific IgE (84.5~98.9%) and IgG antibodies (45.7~71.6%) in comparison with Afu-sensitized mice prophylactically. P1- and P2-treated ABPA mice showed decline in Afu-specific IgE (76.4~88%) and IgG antibodies (15~54%). Increased IgG2a/IgG1 and IFN-${\gamma}$/IL-4 ratios were observed. P1-P3 prophylactically and P1 therapeutically decreased IL-5 levels and eosinophil peroxidase activity. P1 decreased inflammatory cells' infiltration in lung tissue comparable to non-challenged control. Conclusion: Asp f1-derived peptide P1, prophylactically and therapeutically administered to Balb/c mice, is effective in regulating allergic response to allergens/antigens of Afu, and may be explored for immunotherapy of allergic aspergillosis in humans.