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Diverting agents in the oil and gas industry:A comprehensive analysis of their origins,types,and applications

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Petroleum Research 2024年第1期9卷 72-84页

作者： Namrata Bist abhishek nair Kriti Yadav Anirbid Sircar Pandit Deendayal Energy University GandhinagarGujarat382007India Department of Geology Patna UniversityAshok RajpathPatna800005India

During the life of a well,treatments are carried out to boost productivity by stimulating initially unproduced *** treatments include hydraulic fracturing,matrix acidization,and acid fracturing,among *** fracturing treatment is generally applied to deeper reservoirs of oil or natural gas for enhanced *** infusing proppant,water,and chemicals under extreme pressure during the fracturing procedure,fissures in and beneath the reservoir layer can be accessed and *** stimulating procedure,matrix acidization,involves injecting acid down the drilling hole to permeate the rock fissures at stresses lower than the fracture *** addition,carbonate reservoir acid fracturing stimulation is commonly used as an acid treatment technique whereby a pressure greater than the formation disintegration pressure or spontaneous fracture closure pressure is used to compress acid into the *** treatments allow existing wells to sustain hydrocarbon production without new wells being ***,when employed efficiently,can prevent the need to use a rig to provide momentary physical barriers,thus lowering the cost of the *** improvements in diversion technology make use of a variety of degradable particles that act as momentary bridges,either at the perforation entries or inside the existing *** aim of this study is to introduce different types of mechanical and chemical diverters used to enhance the productivity of *** study explains the concepts of different types of diverters and their applications in several formations,it will also help readers to understand the selection procedures based on the suitability and requirements of diverter use by case studies from around the world.

关键词： Refracturing Well treatment Chemical diverter Mechanical diverter Acid fracturing

Imaging of the treated breast post breast conservation surgery/oncoplasty: Pictorial review

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World Journal of Radiology 2017年第8期9卷 321-329页

作者： Subhash K Ramani Ashita Rastogi abhishek Mahajan Nita nair Tanuja Shet Meenakshi H Thakur Department of Radiodiagnosis JJ Hospital Department of Radiodiagnosis and Imaging Tata Memorial Centre Department of Surgical Oncology Tata Memorial Centre Department of Pathology Tata Memorial Centre

Mammographic appearance of the normal breast is altered in the post-operative setting. It is essential to be aware of the normal findings as well as to identify features of recurrent disease with particular emphasis on radiologicalpathological concordance. Digital breast tomosynthesis and volumetric breast density add incremental value in this clinical setting. We present a pictorial review of various cases to illustrate normal post-operative findings as well as mammographic features suspicious for recurrent disease.

关键词： Mammography Digital breast tomosynthesis Breast conservation surgery Post breast-conserving therapy imaging Breast cancer

Artificial Intelligence in hepatology,liver surgery and transplantation:Emerging applications and frontiers of research

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World Journal of Hepatology 2021年第12期13卷 1977-1990页

作者： Fadl H Veerankutty Govind Jayan Manish Kumar Yadav Krishnan Sarojam Manoj abhishek Yadav Sindhu Radha Sadasivan nair T U Shabeerali Varghese Yeldho Madhu Sasidharan Shiraz Ahmad Rather Comprehensive Liver Care VPS Lakeshore HospitalCochin 682040KeralaIndia Hepatobiliary Pancreatic and Liver Transplant Surgery Kerala Institute of Medical SciencesTrivandrum 695029KeralaIndia Department of Radiodiagnosis Kerala Institute of Medical SciencesTrivandrum 695029KeralaIndia Gastroenterology and Hepatology Kerala Institute of Medical SciencesThiruvananthapuram 695029India

The integration of artificial intelligence(AI)and augmented realities into the medical field is being attempted by various researchers across the *** a matter of fact,most of the advanced technologies utilized by medical providers today have been borrowed and extrapolated from other *** introduction of AI into the field of hepatology and liver surgery is relatively a recent *** purpose of this narrative review is to highlight the different AI concepts which are currently being tried to improve the care of patients with liver *** end with summarizing emerging trends and major challenges in the future development of AI in hepatology and liver surgery.

关键词： Liver disease Machine learning Deep learning Artificial neural networks Transplantation Hepatectomy

Performance Comparison of DCT and VQ Based Techniques for Iris Recognition

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Journal of Electronic Science and Technology 2010年第3期8卷 223-229页

作者： H.B.Kekre Tanuja K. Sarode Vinayak Ashok Bharadi abhishek A. Agrawal Rohan J. Arora Mahesh C. nair MPSTME NMIMS University Thadoamal Shahani Engg.College Bandra (w) MPSTME NMIMS Universityand Thakur Engg.College

Iris recognition enjoys universality, high degree of uniqueness and moderate user co-operation. This makes iris recognition systems unavoidable in emerging security ＆ authentication mechanisms. An iris recognition system based on vector quantization （VQ） techniques is proposed and its performance is compared with the discrete cosine transform （DCT）. The proposed system does not need any pre-processing and segmentation of the iris. We have tested Linde-Buzo- Gray （LBG）, Kekre＇s proportionate error （KPE） algorithm and Kekre＇s fast codebook generation （KFCG） algorithm for the clustering purpose. Proposed vector quantization based method using KFCG requires 99.99% less computations as that of full 2-dimensional DCT. Further, the KFCG method gives better performance with the accuracy of 89.10% outperforming DCT that gives accuracy around 66.10%.

关键词： Biometrics discrete cosine transform iris recognition Kekre's fast codebook generation Kekre's proportionate error Linde Buzonad Gray vector quantization.