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Mathematical modelling of ball and plate system with experimental and correlation function-based model validation

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Control Theory and Technology 2024年第2期22卷 326-341页

作者： T.R.Dil kumar S.j.Mija Department of Electrical Engineering National Institute of Technology CalicutKozhikode673601KeralaIndia

The ball and plate system is an inherently nonlinear under actuated benchmark system used for validating the performance of various control schemes. A mathematical model depicting the dynamics close to that of the system is very much required for such a test bed. In this correspondence, the complete nonlinear model, a simplified nonlinear model, and a linearized model of the ball and plate system are developed. The system comprises a ball and plate mechanism and a rotary servo unit. The ball and plate mechanism is modelled using the Euler–Lagrange method, whereas the rotary servo subsystem is modelled from the first principles. The nonlinear model of the combined system is developed by including the dynamics of the servo motor with gear and rolling resistance between the ball and the plate. The simplified nonlinear model of the system is obtained with suitable assumptions. The model is linearized around the operating point using the jacobian. The validity of the developed models is investigated through correlation function analysis. The open-loop response of the three models, viz., nonlinear, simplified nonlinear, and linearized models, is analyzed in the MATLAB/Simulink platform. Since the open-loop system is unstable, the experimental validation of the model is performed with a double-loop PSO (particle swarm optimization) PID control scheme.

关键词： Ball and plate system Correlation function Model validation Particle swarm optimization(PSO) PSO PID controller

Study of Type-B QPOs Observed in Black Hole X-Ray Binary Swift j1728.9-3613

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Research in Astronomy and Astrophysics 2024年第3期24卷 1-9页

作者： Raj kumar Astrophysical Sciences Division Bhabha Atomic Research CentreMumbai 400085India Homi Bhabha National Institute Mumbai 400094India

We report the detection of type-B quasi-periodic oscillation(QPO)of the black hole X-ray binary Swift j1728.9-3613 observed by NICER during the 2019 outburst.A type-B QPO was observed for the first two days and it disappeared as flux increased,but again appeared at∼7.70 Hz when flux was dramatically decreased.The source was found in the soft intermediate state during these observations.We further studied the energy dependence of the QPO.We found that QPO was observed only for a higher energy range implying that the origin of QPO is possibly due to the corona emitting higher energy photons by the inverse Compton process.The variation of spectral parameters can be explained with the disk truncation model.The fractional rms was found to be monotonically increased with energy.The phase lag spectrum followed the“U-shaped”curve.The rms and phase lag spectrum are modeled and explained with the single-component Comptonization model vkompthdk.

关键词： X-rays binaries-accretion-accretion disks-X-rays individual (Swift j1728.9-3613)

Laparoscopic management of remnant gall bladder with stones: Lessons from a tertiary care centre's experience

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Laparoscopic, Endoscopic and Robotic Surgery 2024年第1期7卷 27-33页

作者： Gilbert Samuel jebakumar jeevanandham Muthiah Loganathan jayapal R.Santhosh kumar Siddhesh Tasgaonkar K.S.Santhosh Anand j.K.A.jameel Sudeepta kumar Swain K.j.Raghunath Prasanna kumar Reddy Tirupporur Govindaswamy Balachandar Department of Surgical Gastroenterology Apollo HospitalsChennai 600006India Department of General Surgery Apollo HospitalsChennai 600006India Department of Minimal Access Surgery Apollo HospitalsChennai 600006India

Objective:Laparoscopic cholecystectomy is currently the gold standard for treating symptomatic gallstone disease.Despite its success,approximately 10%of patients may experience persistent biliary symptoms,leading to the post-cholecystectomy syndrome.A remnant gallbladder with cystic duct or bile duct stones is one of the causes of this syndrome.The objective of this study was to shed light on the clinical manifestations,evaluation,therapeutic strategies,and outcomes associated with laparoscopic management of symptomatic remnant gallbladders.Methods:This was a retrospective study,conducted over a five-year period(january 2017 to December 2022)at Apollo Hospitals in South India.All patients who underwent laparoscopic completion cholecystectomy for a remnant gall bladder were included.The following data were collected:patient demographics,symptoms,preoperative investigations,intraoperative details and post operative outcomes.Results:In total,36 patients were included and analysed.The majority of patients were male(25,69.4%),with a mean age of 50.7±12.1 years.The most common presentation was pain in the upper abdomen or right upper quadrant region(24,66.7%).The laparoscopic approach was attempted in all patients,with a success rate of 94.4%.Two patients required conversion to open surgery.Cholecystoenteric fistula to the colon was observed in one patient.Choledocholithiasis was observed in 7 patients(19.4%),and stone clearance was successfully achieved using endoscopic retrograde cholangiopancreatography in all patients preoperatively.Conclusion:Incomplete gall bladder removal either intentionally or unintentionally leaves a remnant gall bladder that is at risk for stone formation and infection.Patients who have this clinical entity with symptoms require a redo or complete cholecystectomy,a complex procedure associated with certain risks.This study highlights the feasibility and safety of laparoscopic completion cholecystectomy for the management of remnant gallbladder with cystic duct or bile duct stones.

关键词： Remnant gall bladder Stump cholecystitis Subtotal cholecystectomy Laparoscopic completion cholecystectomy

Development,validation,and transportability of several machine-learned,non-exercise-based VO_(2max)prediction models for older adults

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journal of Sport and Health Science 2024年第5期13卷 611-620页

作者： Benjamin T.Schumacher Michael j.LaMonte Andrea Z.LaCroix Eleanor M.Simonsick Steven P.Hooker Humberto Parada jr. john Bellettiere Arun kumar Herbert Wertheim School of Public Health and Human Longevity Science University of California San DiegoLa JollaCA 92093USA Department of Epidemiology and Environmental Health School of Public Health and Health ProfessionsUniversity at BuffaloState University of New YorkBuffaloNY 14214USA Translational Gerontology Branch Intramural Research ProgramNational Institute on AgingNational Institutes of HealthBaltimoreMD 21225USA College of Health and Human Services San Diego State UniversitySan DiegoCA 92182USA Division of Epidemiology and Biostatistics School of Public HealthSan Diego State UniversitySan DiegoCA 92182USA University of California San Diego Moores Cancer Center La JollaCA 92093USA Computer Science and Engineering and Halicioglu Data Science Institute University of California San DiegoLa JollaCA 92093USA

Background:There exist few maximal oxygen uptake(VO_(2max))non-exercise-based prediction equations,fewer using machine learning(ML),and none specifically for older adults.Since direct measurement of VO_(2max)is infeasible in large epidemiologic cohort studies,we sought to develop,validate,compare,and assess the transportability of several ML VO_(2max)prediction algorithms.Methods:The Baltimore Longitudinal Study of Aging(BLSA)participants with valid VO2_(max)tests were included(n=1080).Least absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine(SVM)algorithms were trained to predict VO_(2max)values.We developed these algorithms for:(a)the overall BLSA,(b)by sex,(c)using all BLSA variables,and(d)variables common in aging cohorts.Finally,we quantified the associations between measured and predicted VO_(2max)and mortality.Results:The age was 69.0±10.4 years(mean±SD)and the measured VO_(2max)was 21.6±5.9 mL/kg/min.Least absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine yielded root mean squared errors of 3.4 mL/kg/min,3.6 mL/kg/min,3.4 mL/kg/min,3.6 mL/kg/min,and 3.5 mL/kg/min,respectively.Incremental quartiles of measured VO_(2max)showed an inverse gradient in mortality risk.Predicted VO_(2max)variables yielded similar effect estimates but were not robust to adjustment.Conclusion:Measured VO_(2max)is a strong predictor of mortality.Using ML can improve the accuracy of prediction as compared to simpler approaches but estimates of association with mortality remain sensitive to adjustment.Future studies should seek to reproduce these results so that VO_(2max),an important vital sign,can be more broadly studied as a modifiable target for promoting functional resiliency and healthy aging.

关键词： Cardiorespiratory fitness Prediction algorithms Epidemiology Mortality

Integrating artificial intelligence and high-throughput phenotyping for crop improvement

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journal of Integrative Agriculture 2024年第6期23卷 1787-1802页

作者： Mansoor Sheikh Farooq Iqra Hamadani Ambreen kumar A Pravin Manzoor Ikra Yong Suk Chung Phenomics Laboratory Department of Plant Resources and EnvironmentJeju National UniversityJeju 63234Republic of Korea Council of Scientific&Industrial Research Indian Institute of Integrative MedicinePulwamaJ&K 192301India Animal and Dairy Science University of WisconsinMadisonWI 530706United States of America Division of Fruit Science Faculty of HorticultureSher-e-Kashmir University of Agricultural Sciences and Technology of KashmirSrinagar 190025India

Crop improvement is crucial for addressing the global challenges of food security and sustainable agriculture.Recent advancements in high-throughput phenotyping(HTP)technologies and artificial intelligence(AI)have revolutionized the field,enabling rapid and accurate assessment of crop traits on a large scale.The integration of AI and machine learning algorithms with HTP data has unlocked new opportunities for crop improvement.AI algorithms can analyze and interpret large datasets,and extract meaningful patterns and correlations between phenotypic traits and genetic factors.These technologies have the potential to revolutionize plant breeding programs by providing breeders with efficient and accurate tools for trait selection,thereby reducing the time and cost required for variety development.However,further research and collaboration are needed to overcome the existing challenges and fully unlock the power of HTP and AI in crop improvement.By leveraging AI algorithms,researchers can efficiently analyze phenotypic data,uncover complex patterns,and establish predictive models that enable precise trait selection and crop breeding.The aim of this review is to explore the transformative potential of integrating HTP and AI in crop improvement.This review will encompass an in-depth analysis of recent advances and applications,highlighting the numerous benefits and challenges associated with HTP and AI.

关键词： artificial intelligence crop improvement data analysis high-throughput phenotyping machine learning precision agriculture trait selection

均相和非均相催化微藻脂质提取和酯交换制备生物燃料的研究进展

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Chinese journal of Catalysis 2024年第4期59卷 97-117页

作者： Vinoth kumar Ponnumsamy Hussein E.Al-Hazmi Sutha Shobana jeyaprakash Dharmaraja Dipak Ashok jadhav Rajesh Banu j Grzegorz Piechota Bartłomiej Igliński Vinod kumar Amit Bhatnagar Kyu-jung Chae Gopalakrishnan kumarm a高雄医科大学药物与应用化学系环境医学研究中心台湾高雄中国 b高雄医科大学医学研究部台湾高雄中国 c格但斯克理工大学土木与环境工程学院纳鲁特维察格但斯克波兰 d范朗大学工程与技术学院建筑绿色技术与可持续发展研究组胡志明市越南 e工程技术学院科学与人文系化学部泰米尔纳德邦印度 f韩国海洋大学海洋科学与工程学院环境工程系釜山韩国 g泰米尔纳德邦中央大学生命科学系泰米尔纳德邦印度hGPCHEM沼气研究与分析实验室波兰 i尼古拉斯哥白尼大学化学系波兰 j克兰菲尔德大学水与能源学院英国 k拉彭兰塔工业大学工程科学学院分离科学系芬兰 l韩国海洋大学海洋可再生能源工程专业釜山韩国 m延世大学土木与环境工程学院首尔韩国 n斯塔万格大学科学技术学院化学、生物科学与环境工程研究所斯塔万格挪威

随着化石燃料燃烧导致的二氧化碳排放不断加剧气候变化,且化石燃料储量日益减少,寻求可再生能源已成为一项紧迫的任务.其中,藻类衍生可持续燃料因具有成本优势和可运输性,在解决全球能源危机方面展现出广阔前景,备受关注.利用化学转化... 详细信息

随着化石燃料燃烧导致的二氧化碳排放不断加剧气候变化,且化石燃料储量日益减少,寻求可再生能源已成为一项紧迫的任务.其中,藻类衍生可持续燃料因具有成本优势和可运输性,在解决全球能源危机方面展现出广阔前景,备受关注.利用化学转化技术从微藻中提取脂质,并通过酯交换反应可以将其转化为脂肪酸甲酯,是生产绿色生物燃料的有效途径.这一过程涉及游离脂肪酸、磷脂和甘油三酯的提取,并且生产过程能耗低,成为满足日益增长的能源需求的一种理想解决方案.本文综述了微藻脂质提取和酯交换制备生物燃料的相关研究进展.首先,介绍了微藻脂质的提取方法,包括溶剂提取法、索氏提取法、布利格和戴耶法、超临界二氧化碳提取以及离子液体溶剂法等,并分析了各方法的优缺点.随后,重点阐述了酯交换技术在微藻脂质转化中的应用,包括酸碱催化、酶催化以及原位酯交换反应等,并探讨了这些技术的反应机理、催化剂选择、反应器设计以及生物油生产工艺等方面的研究进展.通过综述上述研究进展,为微藻脂质的生产和应用提供了理论指导.研究表明,通过优化催化剂种类、反应条件以及提取方法,可以有效提高微藻脂质的转化效率和生物油品质.同时,本文也指出了当前微藻脂质生产中面临的挑战,如微藻栽培和生长条件优化、高效转化技术的开发等.随着可持续能源日益受到重视,微藻脂质作为一种可再生能源具有巨大的发展潜力.未来研究应进一步关注微藻的规模化栽培、生长条件优化以及高效转化技术的研发,以提高微藻脂质的产量和品质.同时,应进一步推动和实现微藻生物燃料的实际应用,从而为应对气候变化和能源危机提供有效的解决方案.

关键词：微藻脂质提取酯交换催化酶催化原位技术

On the Zeros of a Special Class of Polynomials

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journal of Mathematical Research with Applications 2024年第4期 470-474页

作者： Mahnaz Shafi CHISHTI Vipin kumar TYAGI Mohammad Ibrahim MIR School of Basic and Applied Sciences Shobhit Institute of Engineering and Technology (Deemed to be University) Department of Mathematics University of KashmirSouth Campus

Let P be a complex polynomial of the form P （z）=（λz-a）mΠj=1n-m（z-zj）,where|zj|≥1,1≤j≤n-m.The aim of this paper is to obtain generalisation of a result due to Zargar and Manzoor and a result due to Mir,Nazir and Wani.We shall also obtain an interesting bound which contains the zeros of the second derivative of P （z）.

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A therapeutic potentiality and toxicity concern of nutrient plant Annona squamosa Linn.

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Traditional Medicine Research 2024年第3期9卷 52-65页

作者： Manisha Chandrakar Khomendra kumar Sarwa Vijendra kumar Suryawanshi kumari Pramila University College of Pharmacy Raipur Chhattisgarh Swami Vivekanand Technical University BhilaiChhattisgarh 492001India Department of Pharmacy Government Girls PolytechnicRaipurChhattisgarh 492001India Bharti College of Pharmacy Bharti UniversityDurgChhattisgarh 491001India Faculty of Pharmacy M J College BhilaiDurgChhattisgarh 490023India

Annona squamosa Linn.fruit is famous for its nutritional value with a long history of medicinal benefits due to the presence of many phytochemicals,including alkaloids,diterpenes,essential oil,phytopeptides,etc.Several studies envisaged that Annona squamosa possesses cytotoxic,diuretic,antiurolithiatic,antitumor,anti-psoriatic,antioxidant,and hepatoprotective properties.This plant is traditionally used for the treatment of wound infection,dysentery,seizure,tumors,fever,vomiting,parasitic infections,hypertension,thyroid,toothache,acne,heart disease,inflammation,diabetes,hair loss,dandruff,hemorrhage,maggot-infected sores,abortifacient,and cough.However,some chemical constituents isolated from the plant have shown specific toxic effects in human and animal models,such as acute oral toxic effects,genotoxic,neurotoxic,and ocular toxic.The plant has diverse pharmacological actions,the seeds of this plant possess a genotoxic effect but on the contrary,the bark of the plant shows genoprotective activity.A large number of ethnobotanical studies reported the seed of this plant is used to induce abortion in humans,but a scientific study carried out in pregnant rats reported aqueous seed extract of the plant did not interfere with reproductive performance.The presented review summarized the traditional uses,pharmacological,and toxicological activities of the isolated compounds from this plant.Additionally,some patents and commercial products related to Annona squamosa are also brought up in this article to explore its application which would attract the scientific community to search out its hidden side.

关键词： Annona squamosa cytotoxicity cancer abortifacient genotoxicity isosquamocin annonacin neurotoxicity ocular toxicity

Processing of chromite ultra-fines in a water only cyclone

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International journal of Mining Science and Technology 2017年第6期27卷 1057-1063页

作者： Tripathy Sunil kumar Bhoja sharath kumar Murthy Y. Rama Research and Development Division Tata Steel Ltd. Jamshedpur 831001 India Process Technology Group Tata Steel Ltd. Jamshedpur 831001 India

In the present investigation, an attempt is made to examine the interdependencies among the operating parameters and their interactional effect on the separation performance of a water-only cyclone for treating ferruginous chromite fines. Statistically designed experiments are carried out, and empirical models are developed for the critical response parameters, i,e., yield(%) to underflow, grade(%Cr_2O_3 and%SiO_2)and Cr:Fe ratio of the underflow stream. Further, using these empirical models, operating regime of the process parameters is optimized to obtain the peak performance of water-only cyclone. Also, efforts are made to validate the prediction models with the experimental results.

关键词： Water only cyclone Chromite beneficiation Optimization Factorial designed experiment Statistical modelling