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Optimizing sampling frequency of surface and downhole measurements for efficient stick-slip vibration detection

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Petroleum 2024年第1期10卷 30-38页

作者： Saket srivastava Aditya Sharma Catalin Teodoriu Mewbourne School of Petroleum and Geological Engineering The University of Oklahoma

Drilling vibrations significantly impact drilling operations with high costs due to early downhole equipment failure and loss of productive time. Stick-slip vibrations, a severe form of torsional vibrations,is known to be present up to 50% of total drilling time, making it a topic of immense concern and research. An ongoing discussion in the industry is regarding the reliability of surface measurements for early detection of severe downhole bit sticking. Moreover, most surface measurements are sampled at lower frequency rates closer to 1 Hz. Recently, the implementation of advanced data acquisition modules in downhole subs has greatly improved our understanding of drilling vibrations through high resolution data, sampled up to 10 kHz. However, with a wide range of sampling frequency to choose from different available tools, a critical question remains unanswered. What is an optimal and adequate sampling frequency for early detection of downhole vibrations using both surface and downhole measurements?The paper addresses the question with a focus on stick-slip vibrations through an experimental investigation. Stick slip tests are repeated for different sampling frequencies of surface and downhole measurements and the stick slip index for each case is calculated. The stick-slip index varies for different sampling frequency even though the vibration tests remain completely identical. It was inferred that sampling frequency of measurements greatly impact the detection of downhole vibrations. Even though stick-slip vibrations are characteristically low frequency vibrations(≤2Hz), a minimum of 10Hz sampling frequency is recommended for detection of stick-slip vibrations. Moreover, all characteristics of stick-slip vibrations including bit sticking, bit RPM peaks and negative bit RPMs are clearly observed at a minimum of 100Hz sampling rate.

关键词： Stick-slip

Trace fossil evidences of an Early Miocene paleoseismic event and depositional regime change from the Kutch(Kachchh) Basin

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Journal of Palaeogeography 2024年第1期13卷 165-180页

作者： Ayush srivastava Sudipta Dasgupta Krishanu Chatterjee Mohuli Das Bombay Ichnos Research Group Department of Earth SciencesIndian Institute of Technology Bombay(lIT Bombay)PowaiMumbaiMaharashtra400076India

Unconsolidated siliciclastic sediments can undergo post-burial deformation, which leads to the formation of distinctive sedimentary structures, known as soft-sediment deformation structures(SSDS). The presence of a series of sand volcanoes confined to a particular lithostratigraphic horizon can represent a paleoseismic activity and, thereby, exemplifies the concept of “seismite”. The Kutch Basin has been a tectonically active region since the initiation of eastern Gondwana rifting followed by a tectonic inversion during the Cenozoic due to the collision of the Indian and Eurasian plates. A stratum-bound series of sand volcanoes belonging to the Khari Nadi Formation(KNF) is exposed along the banks of Khari River. They separate the shallow marine deposits below and non-marine deposits above with their characteristic marine and paleosol trace fossil suites, respectively. Although a seismogenic origin has been much debated for the SSDS,the ichnofabric analysis of the sand-volcano-bearing stratum unequivocally points toward such an origin under a shallow seafloor condition. In addition to the sedimentary regime change from an open shallow-marine setting to a continental depositional environment concomitant with basinal uplift, the behavior of the burrowing crustaceans testifies to a syn-depositional development of a fault network associated with the fluidization, sand volcanism, and the resilience of the trace-producers in surviving those processes until the sedimentary regime change in the overlying strata. Although the ichno-sedimentological evidence apparently differs from the previous works that proposed a continuous base-level rise from the beginning of deposition of the Khari Nadi Formation up to the middle part of the overlying Chhasra Formation, the paleoseismic activity,its ichnologic signature, and the depositional regime change refer to a higher-resolution(i.e., lower-order)sequence-stratigraphic change causing a short-duration regression within a longer-durat

关键词： Sand volcano Seismite Ichnology Khari Nadi Formation Kutch Basin Kachchh Basin

IDS-INT:Intrusion detection system using transformer-based transfer learning for imbalanced network traffic

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Digital Communications and Networks 2024年第1期10卷 190-204页

作者： Farhan Ullah Shamsher Ullah Gautam srivastava Jerry Chun-Wei Lin School of Software Northwestern Polytechnical UniversityXian710072ShaanxiChina Knowledge Unit of Systems and Technology University of Management and TechnologySialkot 51040Pakistan Department of Math and Computer Science Brandon UniversityBrandonMB R7A 6A9Canada Department of Computer Science and Math Lebanese American UniversityBeirut1102Lebanon Western Norway University of Applied Sciences BergenNorway Research Centre for Interneural Computing China Medical UniversityTaichungTaiwanChina

A network intrusion detection system is critical for cyber security against llegitimate *** terms of feature perspectives,network traffic may include a variety of elements such as attack reference,attack type,a subcategory of attack,host information,malicious scripts,*** terms of network perspectives,network traffic may contain an imbalanced number of harmful attacks when compared to normal *** is challenging to identify a specific attack due to complex features and data imbalance *** address these issues,this paper proposes an Intrusion Detection System using transformer-based transfer learning for Imbalanced Network Traffic(IDS-INT).IDS-INT uses transformer-based transfer learning to learn feature interactions in both network feature representation and imbalanced ***,detailed information about each type of attack is gathered from network interaction descriptions,which include network nodes,attack type,reference,host information,***,the transformer-based transfer learning approach is developed to learn detailed feature representation using their semantic ***,the Synthetic Minority Oversampling Technique(SMOTE)is implemented to balance abnormal traffic and detect minority ***,the Convolution Neural Network(CNN)model is designed to extract deep features from the balanced network ***,the hybrid approach of the CNN-Long Short-Term Memory(CNN-LSTM)model is developed to detect different types of attacks from the deep *** experiments are conducted to test the proposed approach using three standard datasets,i.e.,UNsWNB15,CIC-IDS2017,and *** explainable AI approach is implemented to interpret the proposed method and develop a trustable model.

关键词： Network intrusion detection Transfer learning Features extraction Imbalance data Explainable AI Cybersecurity

Microstructure transformations and improving wear resistance of austenitic stainless steel additively fabricated by arc-based DED process

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Defence Technology（防务技术） 2024年第8期38卷 194-204页

作者： Ashish Yadav Manu srivastava Prashant K.Jain Sandeep Rathee Hybrid Additive Manufacturing Laboratory Mechanical Engineering DepartmentPDPM Indian Institute of Information TechnologyDesign&ManufacturingJabalpur482005Madhya PradeshIndia FFF Laboratory Mechanical Engineering DepartmentPDPM Indian Institute of Information TechnologyDesign&ManufacturingJabalpur482005Madhya PradeshIndia Department of Mechanical Engineering National Institute of TechnologySrinagarIndia

In this study, austenitic stainless steel(ASS) was additively fabricated by an arc-based direct energy deposition(DED) technique. Macrostructure, microstructure, mechanical characteristics at different spatial orientations(0°, 90°, and 45°), and wear characteristics were evaluated at the deposited structure top, middle, and bottom regions. Results show that austenite(γ) and delta-ferrite(δ) phases make up most of the microstructure of additively fabricated SS316LSi steel. Within γ matrix, δ phase is dispersed both(within and along) grain boundaries, exhibiting a fine vermicular morphology. The bottom, middle,and top regions of WAAM deposited ASS exhibit similar values to those of wrought SS316L in the tensile and impact test findings. Notably, a drop in hardness values is observed as build height increases. During SEM examinations of fractured surfaces from tensile specimen, closed dimples were observed, indicating good ductility of as-built structure. Wear test findings show signs of mild oxidation and usual adhesive wear. By depositing a mechanically mixed composite layer, an increase in the oxidation percentage was discovered to facilitate healing of worn surfaces. The findings of this study will help in design, production and renovation of products/components that are prone to wear. WAAM-deposited ASS has remarkable strength and ability to withstand impacts;it can be used in the production of armour plates for defence applications, mainly military vehicles and aircraft.

关键词： Metal additive deposition Defence applications Arc-based DED Characterization Wear behaviour Fractography

Cooperative Spectrum Sensing Deployment for Cognitive Radio Networks for Internet of Things 5G Wireless Communication

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Tsinghua Science and Technology 2024年第3期29卷 698-720页

作者： Thulasiraman Balachander Kadiyala Ramana Rasineni Madana Mohana Gautam srivastava Thippa Reddy Gadekallu SRM Institute of Science and Technology Tamil Nadu 603203India Lebanese American University Beirut 1102Lebanonand also with Chaitanya Bharathi Institute of TechnologyHyderabad 500075India Chaitanya Bharathi Institute of Technology Hyderabad 500075India Brandon University BrandonR7A 0A1CanadaChinaMedical UniversityTaichung 404327Chinaand Lebanese American UniversityBeirut 1102Lebanon Department of Electrical and Computer Engineering Lebanese American UniversityBeirut 1102Lebanon

Recently,Cooperative Spectrum Sensing(CSS)for Cognitive Radio Networks(CRN)plays a significant role in efficient 5G wireless *** sensing is a significant technology in CRN to identify underutilized *** CSS technique is highly applicable due to its fast and efficient performance.5G wireless communication is widely employed for the continuous development of efficient and accurate Internet of Things(IoT)networks.5G wireless communication will potentially lead the way for next generation IoT *** has established significant consideration as a feasible resource to improve identification performance by developing spatial diversity in receiving signal strength in *** this paper,an optimal CSS for CRN is performed using Offset Quadrature Amplitude Modulation Universal Filtered Multi-Carrier Non-Orthogonal Multiple Access(OQAM/UFMC/NOMA)*** of spectrum and bandwidth utilization is a key challenge in CRN for IoT 5G wireless *** optimal solution for CRN in IoT-based 5G communication should be able to provide optimal bandwidth and CSS,low latency,Signal Noise Ratio(SNR)improvement,maximum capacity,offset synchronization,and Peak Average Power Ratio(PAPR)*** Energy Efficient All-Pass Filter(EEAPF)algorithm is used to eliminate *** deployment approach improves Quality of Service(QoS)in terms of system reliability,throughput,and energy *** in-depth experimental results show that the proposed methodology provides an optimal solution when directly compares against current existing methodologies.

关键词： cooperative spectrum sensing cognitive radio network Internet of Things offset quadratureamplitude modulation universal filtered multi-carrier non-orthogonal multiple access

AGGREGATE SPECIAL FUNCTIONS TO APPROXIMATE PERMUTING TRI-HOMOMORPHISMS AND PERMUTING TRI-DERIVATIONS ASSOCIATED WITH A TRI-ADDITIVEψ-FUNCTIONAL INEQUALITY IN BANACH ALGEBRAS

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Acta Mathematica Scientia 2024年第1期44卷 311-338页

作者： Safoura Rezaei ADERYANI Azam AHADI Reza SAADATI Hari M.srivastava School of Mathematics Iran University of Science and TechnologyNarmakTehranIran Department of Mathematics and Statistics Universtity of VictoriaVictoriaCanada Department of Medical Research China Medical University HospitalChina Medical UniversityTaichung40402China Department of Mathematics and Informatics Azerbaijan University71 Jeyhun Hajibeyli StreetAZ1007BakuAzerbaijan Section of Mathematics International TelematicUniversity UninettunoI-00186RomeItaly

In this paper,we define a new class of control functions through aggregate special *** class of control functions help us to stabilize and approximate a tri-additiveψ-functional inequality to get a better estimation for permuting tri-homomorphisms and permuting tri-derivations in unital C*-algebras and Banach algebras by the vector-valued alternative fixed point theorem.

关键词： permuting tri-homomorphism in Banach algebra permuting tri-derivation on C*-algebra fixed point theorem Ulam-Hyers-Rassias stability aggregate special functions tri-additiveψ-functional inequality

A review of torsional vibration mitigation techniques using active control and machine learning strategies

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PETROLEUM 2024年第3期10卷 411-426页

作者： Sharma, Aditya Abid, Khizar srivastava, Saket Velasquez, Andres Felipe Baena Teodoriu, Catalin Univ Oklahoma Norman OK 73019 USA

Drilling is one of the most challenging and expensive processes in hydrocarbon extraction and geothermal well development. Dysfunctions faced during drilling can increase the non-productive time (NPT) greatly, resulting in inflating the drilling cost and also pose a safety concern. One of the main problems faced during drilling that limits the life of drilling equipment and tools and decreases the overall productivity of the system is drilling vibrations. These vibrations can be categorized into three modes: axial, lateral, and torsional. Stick-slip vibrations are a type of torsional vibration in which the bottom hole assembly (BHA) periodically stops to rotate followed by a spike in the bottom hole RPM. This paper provides a comprehensive review of techniques used to control and mitigate torsional vibration with an emphasis on stick-slip. A brief introduction to drillstring and friction modeling is presented followed by a concise summary of passive control techniques to control stick-slip. Then the focus is shifted to an up-to-date review of active control and machine learning for stick-slip control and mitigation. The paper ultimately highlights the importance of adapting novel control and mitigation concepts to improve stick slip detection and improve the overall drilling process. A unique solution is insufficient to control a complex process such as drilling, but integration of various techniques has been found promising. (c) 2023 Southwest Petroleum University. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http:// ***/licenses/by-nc-nd/4.0/).

关键词： Drilling vibrations Controllers Mitigations strategies Stick slip Torsional vibrations Machine Learning STICK-SLIP OSCILLATIONS DRILLSTRING VIBRATION BENDING VIBRATIONS OUTPUT-FEEDBACK DRAG BITS DESIGN SUPPRESSION STABILITY SYSTEM MODEL

Natural product-based treatment potential for type 2 diabetes mellitus and cardiovascular disease

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World Journal of Diabetes 2024年第7期15卷 1603-1614页

作者： Dharmsheel Shrivastav Satyam Kumar Kumbhakar Shivangi srivastava Desh Deepak Singh Amity Institute of Biotechnology Amity University RajasthanJaipur 303002RajasthanIndia Department of Biotechnology Govt Veer Surendra Say P.G.CollegeGariaband 493889ChhattisgarhIndia Department of Life Science Chhatrapati Shahu ji Maharaj UniversityKanpur 208024Uttar PradeshIndia

BACKGROUND Type 2 diabetes(T2D)is a metabolic disease of impaired glucose utilization and a major cause of cardiovascular disease(CVD).The pathogenesis of both diseases shares common risk factors and mechanisms,and both are significant contributors to global morbidity and *** of natural products for T2D mellitus(T2DM)and CVD can be seen as a potential preventive and effective therapeutic *** To critically evaluate the therapeutic potential of natural products in T2D and coronary artery disease(CAD).METHODS By using specific keywords,we strategically searched the PubMed *** controlled trials(RCTs)were searched as the primary focus that examined the effect of natural products on glycemic control,oxidative stress,and antioxidant *** focused on outcomes such as low blood glucose levels,adjustment on markers of oxidative stress and *** screening fulllength papers,we included 9 RCTs in our review that met our inclusion *** In the literature search on the database,we found that various natural products like plant secondary metabolites play a diverse role in the management of *** ginseng,sesame oil and cocoa flavanols proved effective in lowering blood glucose levels and controlling blood pressure,which are key factors in managing T2DM and *** diabetic patients Melissa officinalis effectively reduce inflammation and shows diabetes *** fish oil and flaxseed oil reduced insulin levels and inflammatory markers,suggesting benefits for both *** lipid profile and endothelial function were enhanced by Nigella sativa oil and Terminalia chebula,which is significant for the management of cardiovascular risk factors in *** Bilberry extract also showed promise for improving glycemic control in patients with *** The high level of antioxidant,anti-inflammatory,and anti-angiogenic properties found in natural products makes them promising therapeutic opt

关键词： Type 2 diabetes mellitus Cardiovascular disease Natural products Antioxidants Oxidative stress Therapeutic impact Global burden

Lipid-nanoparticle-enabled nucleic acid therapeutics for liver disorders

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Acta Pharmaceutica Sinica B 2024年第7期14卷 2885-2900页

作者： Porkizhi Arjunan Durga Kathirvelu Gokulnath Mahalingam Ashish Kumar Goel Uday George Zacharaiah Alok srivastava Srujan Marepally Center for Stem Cell Research(A Unit of inStem Bengaluru)Christian Medical College CampusBagayamVellore 632002Tamil NaduIndia Manipal academy for higher education Mangalore 576104KarnatakaIndia Department of Hematology Christian Medical College&HospitalVellore 632004Tamil NaduIndia Department of Hepatology Christian Medical College&HospitalVellore 632004Tamil NaduIndia

Inherited genetic disorders of the liver pose a significant public health *** transplantation is often limited by the availability of donor livers and the exorbitant costs of immunosuppressive *** overcome these limitations,nucleic acid therapy provides a hopeful alternative that enables gene repair,gene supplementation,and gene silencing with suitable *** viral vectors are the most efficient and preferred for gene therapy,pre-existing immunity debilitating immune responses limit their *** a potential alternative,lipid nanoparticle-mediated vectors are being explored to deliver multiple nucleic acid forms,including pDNA,mRNA,siRNA,and ***,we discuss the broader applications of lipid nanoparticles,from protein replacement therapy to restoring the disease mechanism through nucleic acid delivery and gene editing,as well as multiple preclinical and clinical studies as a potential alternative to liver transplantation.

关键词： Lipid nanoparticle Liver disorders Gene therapy Gene editing Nucleic acid delivery pDNA mRNA siRNA ASO Clinical trials