GEOMECHANICAL STATE OF ROCKS WITH DEPLETION IN UNCONVENTIONAL COALBED METHANE RESERVOIRS

AN ABSTRACT OF THE DISSERTATION OFSUMAN SAURABH, for the Doctor of Philosophy degree in Engineering Science, presented on August 30, 2019, at Southern Illinois University Carbondale.TITLE: GEOMECHANICAL STATE OF ROCKS WITH DEPLETION IN UNCONVENTIONAL COALBED METHANE RESERVOIRSMAJOR PROFESSOR: Dr. Satya HarpalaniOne of the major reservoir types in the class of unconventional reservoirs is coalbed methane. Researchers have treated these reservoirs as isotropic when modeling stress and permeability, that is, mechanical properties in all directions are same. Furthermore, coal is a highly sorptive and stress- sensitive rock. The focus of this dissertation is to characterize the geomechanical aspects of these reservoirs, strain, stresses, effective stress and, using the information, establish the dynamic flow/permeability behavior with continued depletion. Several aspects of the study presented in this dissertation can be easily extended to shale gas reservoirs. The study started with mechanical characterization and measurement of anisotropy using experimental and modeling work, and evaluation of how the sorptive nature of coal can affect the anisotropy. An attempt was also made to characterize the variation in anisotropy with depletion. The results revealed that the coals tested were orthotropic in nature, but could be approximated as transversely isotropic, that is, the mechanical properties were isotropic in the horizontal plane, but significantly different in vertical direction. Mechanical characterization of coal was followed by flow modeling. Stress data was used to characterize the changes in permeability with depletion. This was achieved by plotting stress path followed by coal during depletion. The model developed was used to successfully predict the permeability variation in coal with depletion for elastic deformations. As expected, the developed model failed to predict the permeability variation resulting from inelastic deformation given that it was based on elastic constitutive equations. Hence, the next logical step was to develop a generalized permeability model, which would be valid for both elastic and inelastic deformations. Investigation of the causes of coal failure due to anisotropic stress redistribution during depletion was also carried out as a part of this study. It was found that highly sorptive rocks experience severe loss in horizontal stresses with depletion and, if their mechanical strength is not adequate to support the anisotropic stress redistribution, rock failure can result. In order to develop a generalized permeability model based on stress data, stress paths for three different coal types were established and the corresponding changes in permeability were studied. Stress path plotted in an octahedral mean stress versus octahedral shear stress plane provided a signal for changes in the permeability for both elastic as well as inelastic deformations. This signal was used to develop a mechanistic model for permeability modeling, based on stress redistribution in rocks during depletion. The model was able to successfully predict the permeability variation for all three coal types. Finally, since coal is highly stress- sensitive, changes in effective stresses were found to be the dictating factor for deformations, changes in permeability and possible failure with depletion. Hence, the next step was to develop an effective stress law for sorptive and transversely isotropic rocks. For development of an effective stress law for stress sensitive, transversely isotropic rocks, previously established constitutive equations were used to formulate a new analytical model. The model was then used to study changes in the variation of Biot’s coefficient of these rocks. It was found that Biot’s coefficient, typically less than one, can take values larger than one for these rocks, and their values also change with depletion. The study provides a methodology which can be used to estimate the Biot’s coefficient of any rock. As a final step, preliminary work was carried out on the problem of under-performing coal reservoirs in the San Juan basin, where coal is extremely tight with very low permeability. An extension of the work presented in this dissertation is to use the geomechanical characterization techniques to unlock these reservoirs and improve their performance. The experimental data collected during this preliminary study is included in the last chapter of the dissertation

Privacy-Preserving Techniques in Artificial Intelligence Applications for Industrial IOT Driven Digital Transformation

The advent of Industry 4.0 has brought about a revolution in the Industrial Internet of Things (IIoT) driving digital transformation, which now includes data analytics, cloud computing, artificial intelligence, and mobile connectivity. This paper delves into the effectiveness of existing privacy protection measures, as well as the challenges and opportunities presented by emerging technologies such as unified encryption and machine learning. Additionally, the paper provides insights into the processes required for industry-specific compliance with relevant laws and regulations. The findings emphasize the crucial role privacy plays in AI applications for IIoT systems and shed light on the strategies, obstacles, and prospects that organizations must navigate in this rapidly evolving landscape

Navigating the Landscape of Robust and Secure Artificial Intelligence: A Comprehensive Literature Review

Addressing the multidimensional nature of Artificial Intelligence assurance, this thorough survey is dedicated to elaborating on various aspects of ensuring the reliability and safety of computerized systems. It steers through the turbulent seas of model enervates, unmodelled phenomena, and security menaces to give an elaborate lit review. The review touches upon the boisterous ways of addressing these intricate mitigation strategies for model errors used in the past, the challenges of under-specification with modern ML models, and how understanding uncertainty is crucial. In addition, it evaluates the AI system’s security basis, the emerging Adversary Machine Learning field, and its processes necessary for testing and evaluation of weaker adversarial case studies. The review of literature also looks upon the situation of DoD context, how the terrain surrounding developmental and operational testing is altering with all these shifts in culture that must be implemented if not to implement robust but secure AI implementation

SEX-SELECTIVE ABORTIONS IN INDIA: A BEHAVIOURAL EPIDEMIC

Sex- selective abortions have been known to be a problem in India. A study titled “Trends in selective abortions of girls in India: analysis of nationally representative birth histories from 1990 to 2005 and census data from 1991 to 2011” by Jha P et al was published in Lancet in May 2011 presented the first nationally representative analysis of trends in sex-selective abortions in India. It came as an aftermath of the provisional 2011 census release which showed a fall in 0-6 year sex ratio from 927 in 2001 to 914 in 20111. 56 percent of Indian districts have child sex-ratio of less than 9152, spreading to areas where the sex-selective abortions were known to be negligible. This was in contrast to the fact that overall sex-ratio increased from 933 to 9401,3.Such findings necessitate a more specific approach to this problem by looking at the trends in child sex-ratio unlike the crude analysis of overall sex-ratios adopted earlier. Also this study provides an estimate of sex-selective abortions from 1980 to 2010 ranging from 4.2-12.1 million

Customer Segmentation and Business Sales Forecasting using Machine Learning for Business Development

This study explores the application of machine learning techniques for business development, focusing on sales prediction and customer segmentation, using a Walmart dataset. Performance metrics include Mean Absolute Error (MAE) and R2 scores. Our hybrid approach combines the BIRCH algorithm with time-lagged machine learning (TL-ML). The results reveal that customer segmentation significantly improves model performance across all metrics. Among the techniques tested, models incorporating customer segmentation (CS-RFR and CS-TL-ML) outperform standard Random Forest Regressor models. Specifically, CS-TL-ML shows a slight advantage in terms of both lower MAE and higher R2 scores, confirming its efficacy for sales prediction and customer segmentation tasks

Resorcinol-formaldehyde based carbon nanospheres by electrospraying

Carbon nanospheres were synthesized using sol-gel processing of organic and aqueous resorcinol formaldehyde (RF) sols combined with electrospraying technique. RF sol was electrosprayed to form nano-droplets which were collected on a Si wafer. After oven drying at 60°C for 12 h, RF nano-droplets were pyrolyzed at 900°C in an inert atmosphere to yield the carbon nanospheres. This study reports the optimization of various process parameters including needle diameter, applied electric potential and liquid flow rate in order to get spherical, mono-disperse particles. For the organic RF sol, the optimized parameters, needle diameter 0.241 mm, electric potential, 1.5 kV/cm and a flow rate of 0sd8 ml/h, enabled the synthesis of nearly monodispersed carbon nano-spheres with diameter of 30.2 ± 7.1 nm. With the same conditions, aqueous RF sol produced irregularly shaped nanoparticles with a smaller mean diameter and much higher variance (17.4 ± 8.0 nm). The surface properties were significantly influenced by the surface morphologies as demonstrated by the water contact angle (WCA) studies. The surface covered with the RF derived carbon nano-spheres was extremely hydrophilic (WCA 10·1°) as compared to a much weaker hydrophilicity of the RF derived carbon films (WCA 83·3°). The hydrophilic carbon nanospheres reported here may have potential applications as adsorbents and in controlled drug delivery, biosensors and carbon-based microelectromechanical systems (C-MEMS) including bio-MEMS

PREGABALIN VS. DULOXETINE FOR POSTOPERATIVE ANALGESIC REQUIREMENTS FOLLOWING LOWER LIMB ORTHOPAEDIC SURGERY: A RANDOMIZED STUDY.

Background After lower limb procedures, acute postoperative pain must be managed well for patient recovery. Preemptive analgesics Pregabalin and Duloxetine, with different mechanisms, are promising. The study evaluates the effectiveness of Pregabalin versus Duloxetine in managing acute post-operative pain following lower limb orthopedic surgeries. Methods 120 individuals were included receiving spinal anaesthesia for elective lower limb procedures were included. Three groups of participants were created: Group P (pregabalin, n=40), Group D (duloxetine, n=40), and Group C (control, n= 40). The Visual Analogue Scale (VAS) was used to measure pain at different postoperative intervals. The Ramsay sedation scale was used to gauge the degree of sedation. Evaluations were also conducted on patient satisfaction, adverse effect frequency, and opioid intake. Version 16 of SPSS was used for statistical analysis. Results The three groups had similar mean ages, for Group C (34.80 ± 13.557), Group D (36.48 ± 15.262), and Group P (35.18 ± 13.756). The VAS scores indicated significantly lower pain levels in Group P at 2, 4, 6, and 12 hours postoperatively compared to Groups C and D (P < 0.001). Group P also showed significantly lower opioid consumption (130.88 ± 14.627 mcg/kg) compared to Groups C and D (P < 0.001). Sedation levels were higher in Group P at 2 and 4 hours postoperatively (P = 0.001). Side effects included sedation in Group P and post-operative nausea and vomiting in Group D. Conclusion Though it caused more drowsiness, pregabalin reduced immediate post-operative pain and opioid use after lower limb procedures better than Duloxetine. Duloxetine was beneficial but increased postoperative nausea and vomiting. Recommendations Pregabalin is suggested for immediate postoperative pain in lower limb procedures due to its superior pain relief and opioid-sparing benefits. However, its sedative qualities should be considered and used only in those who can take more sedation

Recent Trends in Freshwater Pearl Farming in India

Cultured pearls have an important place in international trade. The Vedas, the Bible, and the Koran all mentioned pearls, and they are regarded as one of the highest honours. Pearls are generated in nature when an irritant, such as a sand grain or a parasite, is swept into the pearl molluscs and lodged within it, where it is coated with micro-layers of nacre, a lustrous substance made up of 80–90 per cent aragonite crystals of CaCO3. The ICAR-Central Institute of Freshwater Aquaculture (CIFA), Kausalyaganga, Bhubaneswar, India, has created a base technology for cultivating pearls in freshwater habitats, recognising the scope and value of freshwater pearl production. Indian pond mussel, Lamellidens marginalis is the major species used in freshwater pearl aquaculture. In addition, ICAR-CIFA has pioneered a novel feature of freshwater pearl farming. The Institute has also taken the lead in disseminating freshwater pearl culture technology to the country’s fish farming communities, entrepreneurs, researchers, and students to build a sustainable model for the country’s socio-economic development. In this chapter, we will briefly cover pearls and their types, their historical significance, the spread of pearl mussels of freshwater origin in various countries, pearl biomineralisation, pearl farming techniques, and factors affecting pearl quality, among other things

Insights of Breast Cancer and Barriers to its Therapy

Breast cancer is the most common cancer across the globe occurring commonly in women population, and it is one of the main causes of mortality in women. In 2018, 1,62,468 new cases and 87,090 death cases of breast cancer were registered in India. In these recent years, lots of studies were conducted in breast cancer related to treatment and management, but in spite of getting so much advancement in the treatment of breast cancer still, the mortality rate of women is increasing day by day. Numerous factors are acting as barriers or challenges in breast cancer preventive therapy. It includes lack of knowledge regarding the treatment of cancer and patient getting insecure about treatment, fear of having side effects, cost of treatment and the efficacy of the drugs being prescribed. The study intended to determine the perceived insights and barriers to treatment of breast cancer

Compliance, enablers and barriers to implementation of the cigarette and other tobacco products act, in Jodhpur, Rajasthan

Section 6 of the cigarette and other tobacco products act (COTPA) of India, lays down provisions and offences against tobacco sale to minors and near educational institutions. Considering well-documented violations and the significance of its better implementation, this study was planned to assess the knowledge and attitudes and compliance regarding provisions of COTPA section 6 among stakeholders, and identify potential enablers and barriers to implementation of the act. A cross-sectional study was conducted in ten senior secondary schools, two each from 5 zones of Jodhpur district. Principal and staff were interviewed to assess their knowledge and awareness, while a checklist was used to observe the compliance in the vicinity of schools. In-depth interviews were conducted amongst stakeholders to identify enablers and barriers. Only nine (45%) participants were aware about COTPA and six (30%) knew whom to report any violation. 60% schools had international “no smoking” signage and vendors were observed near 50% of the schools. Sale to minors was observed at two such stalls. Observed barriers were related to law and act, implementing personnel and community. Sensitisation of health hazards, intersectoral collaborations with prompt reporting might enhance compliance towards the law