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Detection of internal crack growth in polyethylene pipe using guided wave ultrasonic testing

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 319-329页

作者： Jay kumar shah Hao Wang Said El-Hawwat Centre of Advanced Infrastructure and Transportation RutgersThe State University of New JerseyNJ 08854USA Department of Civil and Environmental Engineering RutgersThe State University of New JerseyNJ 08854USA

Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively *** growth of internal cracks in PE pipe severely affects its pressure-holding capacity,hence the early detection of internal cracks is crucial for effective pipeline maintenance *** study extends the scope of guided wave-based ultrasonic testing to detect the growth of internal cracks in a natural gas distribution PE *** experiments and a finite element model were planned to study the wave-crack interaction at different stages of axially oriented internal crack growth with a piezoceramic transducer-based setup arranged in a pitch-catch *** dispersion analysis supplemented with preliminary experiments was performed to isolate the optimal inspection frequency,leading to the selection of the T(0,1)mode at 50-kHz for the investigation.A transmission index based on the energy of the T(0,1)mode was developed to trace the extent of simulated crack *** findings revealed an inverse linear correlation between the transmission index and the crack depth for crack growth beyond 20%crack depth.

关键词： polyethylene pipes internal cracks guided wave ultrasonic testing torsional modes finite element modeling

Design of a Low Loss RF Mixer in Ku-Band (12 - 18 GHz)

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Wireless Engineering and Technology 2012年第1期3卷 46-50页

作者： sanjeev kumar shah Rudra Pratap Singh Chauhan Sanjay Singh Lalit Pandey Sandeep Singh 不详

The goal of this paper is to design and develop low conversion loss mixers at Ku Band (12 - 18 GHz) in microstrip line configuration. The Ku-band (Kurtz-under band) is primarily used for satellite Communications, particularly for editing and broadcasting satellite television. CAD tools (Agilent’s Advance Design System software) have been used for simulation and optimization of the circuits. 180 degree balanced mixer configuration has been adopted due to better RF to LO isolation requirement. The circuit is designed on microstrip line using RT Duroid (Dielectric Constant = 2.22). Initially a rat race coupler (180 degree hybrid) was designed and simulated and optimized for required performance successfully.

关键词： Single Balanced Mixer Double Balanced Mixer

Clinical outcomes of triceps reflecting anconeus pedicle and olecranon osteotomy approach for distal humerus intercondylar fractures

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World Journal of Orthopedics 2024年第6期15卷 570-577页

作者： Rohit Ailani sanjeev kumar Bhuyan Brejesh kumar Prasad Amit kumar Namrata Dawani Department of Orthopaedics Lovee Shubh HospitalLucknowUttar Pradesh 226002India Department of Orthopaedics Gauhati Medical CollegeGuahati 781032India Department of Orthopaedics ESIC Medical College and HospitalFaridabadHaryana 121001India Department of Orthopaedics All India Institute of Medical SciencesKalyaniWest Bengal 741245India Department of Obstetric and Gynecology Kannauj Medical CollegeKannaujUttar Pradesh 209732India

BACKGROUND The preferred treatment for distal humeral intercondylar fractures is open reduction and internal *** there is consensus about the posterior approach,several posterior approaches have been *** is debatable as to which approach is *** To compare triceps reflecting anconeus pedicle(TRAP)and olecranon osteotomy approaches for internal fixation of distal humeral intercondylar *** In total,40 cases of Arbeitsgemeinschaft für Osteosynthesefragen/Association of the Study of Internal Fixation type C,closed,and Gustilo type I intercondylar humeral fractures were *** ranged in age from 18 years to 70 *** patients were randomized into two groups:TRAP group and olecranon osteotomy group,with 20 cases in *** were followed up at 6 wk,3 months,6 months,and 12 *** outcomes were measured in terms of flexion-extension arc,Disabilities of Arm,Shoulder and Hand score,and Mayo Elbow Performance *** The mean age was 43.2 years in the TRAP group and 37.5 years in the olecranon osteotomy *** mean operative time and mean duration of hospital stay in the TRAP group were significantly higher than in the olecranon osteotomy group(119.5 vs 111.5 min and 9.85 vs 5.45 d,respectively).The mean arc of flexion-extension,Disabilities of Arm,Shoulder and Hand score,and Mayo Elbow Performance Score were comparable without any significant difference in the groups at the 12-month follow-up(107.0 vs 106.2,18.3 vs 15.7,and 84.2 vs 86.2,respectively).Ulnar paresthesia and superficial infections were comparable in both groups(2 cases vs 3 cases and 3 cases vs 2 cases,respectively).Hardware prominence was significantly higher in the olecranon osteotomy group,mostly due to tension band *** Both approaches were equivalent,but there is a need for further study including higher numbers of subjects and longer study duration to prove the benefits of one approach over the other.

关键词： Elbow joint Humeral fracture Osteotomy Internal Fracture fixation

Comprehending drivers of land use land cover change from 1999 to 2021 in the Pithoragarh District,Kumaon Himalaya,Uttarakhand,India

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Journal of Mountain Science 2024年第7期21卷 2394-2407页

作者： Mahika PHARTIYAL sanjeev SHARMA Centre for the Study of Regional Development Jawaharlal Nehru UniversityNew Delhi 110067India

The Himalayan region has been experiencing stark impacts of climate change,demographic and livelihood pattern *** analysis of land use and land cover(LULC)change provides insights into the shifts in spatial and temporal patterns of *** changes are the combined effects of anthropogenic and natural/climatic *** present study attempts to monitor and comprehend the main drivers behind LULC changes(1999-2021)in the Himalayan region of Pithoragarh district,*** district is a border district,remotely located in the north-east region of Uttarakhand,*** study draws upon primary and secondary data sources.A total of 400 household surveys and five group discussions from 38 villages were conducted randomly to understand the climate perception of the local community and the drivers of *** imagery,CRU(Climatic Research Unit)climate data and climate perception data from the field have been used to comprehensively comprehend,analyze,and discuss the trends and reasons for LULC *** and remote sensing techniques were used to construct LULC *** multifaceted approach ensures comprehensive and corroborated *** classes were identified and formed viz-cultivation,barren,settlement,snow,and *** show that vegetation and builtup have increased whereas cultivation,barren land,and snow cover have *** study further aims to elucidate the causes behind LULC changes in the spatially heterogeneous region,distinguishing between those attributed to human activities,climate shifts,and the interconnected impacts of *** study provides a comprehensive picture of the study area and delivers a targeted understanding of local drivers and their potential remedies by offering a foundation for formulating sustainable adaptation policies in the region.

关键词： Himalayan region Land use/land cover change Anthropogenic factors Climate change Socioecological system

Optimizing Optical Fiber Faults Detection:A Comparative Analysis of Advanced Machine Learning Approaches

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Computers, Materials & Continua 2024年第5期79卷 2697-2721页

作者： Kamlesh kumar Soothar Yuanxiang Chen Arif Hussain Magsi Cong Hu Hussain shah School of Electronics Engineering Beijing University of Posts and TelecommunicationsBeijing100876China State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an710071China State Key Laboratory ofNetworking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing100876China

Efficient optical network management poses significant importance in backhaul and access network communicationfor preventing service disruptions and ensuring Quality of Service(QoS)*** emerging faultsin optical networks introduce challenges that can jeopardize the network with a variety of *** existingliterature witnessed various partial or inadequate *** the other hand,Machine Learning(ML)hasrevolutionized as a promising technique for fault detection and *** traditional fault managementsystems,this research has three-fold ***,this research leverages the ML and Deep Learning(DL)multi-classification system and evaluates their accuracy in detecting six distinct fault types,including fiber cut,fibereavesdropping,splicing,bad connector,bending,and PC ***,this paper assesses the classificationdelay of each classification ***,this work proposes a fiber optics fault prevention algorithm thatdetermines to mitigate the faults *** work utilized a publicly available fiber optics dataset namedOTDR_Data and applied different ML classifiers,such as Gaussian Naive Bayes(GNB),Logistic Regression(LR),Support Vector Machine(SVM),K-Nearest Neighbor(KNN),Random Forest(RF),and Decision Tree(DT).Moreover,Ensemble Learning(EL)techniques are applied to evaluate the accuracy of various *** addition,this work evaluated the performance of DL-based Convolutional Neural Network and Long-Short Term Memory(CNN-LSTM)hybrid *** findings reveal that the CNN-LSTM hybrid technique achieved the highestaccuracy of 99%with a delay of 360 *** the other hand,EL techniques improved the accuracy in detecting fiberoptic ***,this research comprehensively assesses accuracy and delay metrics for various classifiers andproposes the most efficient attack detection system in fiber optics.

关键词： Fiber optics fault detection multiclassification machine learning ensemble learning

Morphological and molecular description of a new species of sandfly,Sergentomyia(Neophlebotomus)ashwanii ***.(Diptera:Psychodidae)from Western Ghats,India

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Asian Pacific Journal of Tropical Medicine 2024年第5期17卷 226-234页

作者： Prasanta Saini Harish kumar shah Mathew Jessu Sonia T Tom Anns KP Amju ICMR-Vector Control Research Centre(Field Station) KottayamKeralaIndia

Objective:To report a new species of sandfly,Sergentomyia(Neophlebotomus)ashwanii ***.(Diptera:Psychodidae)from Western Ghats,***:A systematic sandfly survey was conducted in the Thrissur and Kollam districts of Kerala,India using mechanical aspirators,light and sticky traps,both indoor and outdoor habitats,for a period of one *** acid barcoding of samples was performed targeting mitochondrial cytochrome oxidase I(COI)gene and sequence generated was subjected to phylogenetic ***:Sergentomyia(Neophlebotomus)ashwanii,a new sandfly species is recorded and described in this communication.A single row of 10-12 pointed teeth in the cibarium with 4-6 small denticles or fore-teeth are the key characteristics that is distinctive from other members of the subgenus *** COI barcode followed by phylogenetic analysis of the nucleotide sequence confirms that specimens of the species belong to the same taxonomic group while the genetic distance(14.2%)with the congeners established it to be a different ***:The Western Ghats'being an important biodiversity hotspot and has dearth of systematic entomological surveys on *** current study tried to fill the void and also report a new sandfly species.

关键词： Sergentomyia(Neophlebotomus)ashwanii COI barcode Western Ghats Phlebotomine sandflies

Numerical analysis of the return flow solar air heater(RF-SAH)with assimilation of V-type artificial roughness

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Energy and Built Environment 2024年第2期5卷 185-193页

作者： Prashant Raturi Hemlata Deolal sanjeev Kimothi Department of Mechanical Engineering Swami Rama Himalayan University Dehradun248140India Department of Mechanical Engineering DIT UniversityDehradun248001India Division of Research&Innovation Dept.of PhysicsUttaranchal University248007India

A novel design of Return Flow Solar Air Heater(RFSAH)with different arrangements of baffles especially V-Type Artificial roughness is simulated and numerically analyzed with energy balance *** enhance the effectiveness of baffles,numerous studies have been *** performance of the RFSAH is studied in terms of thermal efficiency,thermo-hydraulic efficiency,and optimization of baffle *** Thermal efficiency and thermo-hydraulic efficiency are found in RFSAH with baffle on both sides of the absorber plate and mass flow rate above 0.2kg/*** analysis of the influencing parameters is carried out and reported the best performance of the system on selective geometrical parameters(ψ=0.7,β=20%,e/H=1,p/e=0.8,α=60°).The results obtained from the present model are validated with the published experimental results and have been found in quite reasonable agreement with an average error of 16.45%.Thermal and Thermohydraulic efficiency of RFSAH with a baffle on both sides of the absorber plate is maximum among baffles below,above,and on both sides of the absorber *** is observed that the thermal efficiency of RFSAH is greater than *** proposed optimum baffles roughness is suggested to increase the air upholding time period for more efficient output.

关键词： Numerical analysis Energy Balance Equations Thermal Efficiency Return flow solar air heater V-baffles

Effect of cooling media on bead geometry,microstructure,and mechanical properties of wire arc additive manufactured IN718 alloy

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Advances in Manufacturing 2024年第1期12卷 124-149页

作者： Parveen kumar Satish kumar Sharma Ratnesh kumar Raj Singh Department of Mechanical Engineering Thapar Institute of Engineering and TechnologyPatialaPunjab147004India

This work aims to present and explore thermal management techniques for the wire arc additive manufacturing(WAAM)of IN718 *** heat can be mitigated via air or water *** this study,the material was deposited under four different heat-input conditions with air or water *** air cooling,the layer is deposited in a normal atmospheric air environment,whereas with water cooling,the material is deposited inside a water tank by varying the water *** validate the air and water cooling thermal management techniques,IN718 single-pass and multilayer linear walls were deposited using the bidirectional gas metal arc welding based WAAM setup under four different heat input *** the deposition of single layers,the temperature profiles were recorded,and the geometric and microstructural features were *** multilayer wall structures,the mechanical properties(hardness,tensile strength,and elongation)were determined and assessed using the corresponding microstructural features explored through scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),and electron backscatter diffraction(EBSD)*** microstructure observed through SEM analysis in the building direction was found to be nonhomogenous compared with that in the deposition ***,water cooling was found to govern bead characteristics,such as wall width and *** grain size and anisotropy of the mechanical properties also decreased in the water-cooled ***,water cooling is an economical and efficient method to mitigate excessive heat accumulation in WAAM-deposited IN718.

关键词： Air cooling Water cooling IN718 Bead characteristics Microstructure Electron backscatter diffraction(EBSD)

Betulin protects against isoproterenol-induced myocardial injury by inhibiting NF-κB signaling and attenuating cardiac inflammation and oxidative stress in rats

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Asian Pacific Journal of Tropical Biomedicine 2024年第6期14卷 236-244页

作者： Hital shah Tejal Gandhi Gujarat Technological University AhmedabadGujarat 382424India Department of Pharmacology Anand Pharmacy CollegeAnandGujarat 388001India

Objective:To investigate the cardioprotective potential of betulin in isoproterenol(ISO)-induced myocardial injury in ***:Wistar rats were divided into five groups(n=10):normal,ISO,nebivolol 5 mg/kg,and betulin(20&40 mg/kg).Nebivolol and betulin were administered orally for 29 ***(85 mg/kg)was administered subcutaneously on day 27 and day 28 to induce myocardial *** day 29,blood was collected for determination of cardiac markers,and hemodynamic parameters were *** levels of oxidative stress markers and the gene expressions of apoptotic markers and inflammatory mediators were ***,2,3,5-triphenyltetrazolium chloride staining and histopathological analysis were also ***:Betulin reduced the size of myocardial infarction,decreased elevated levels of cardiac enzymes,and maintained hemodynamic *** also inhibited ISO-induced upregulation of Bax,caspase-3,NF-κB,and IL-6,enhanced endogenous antioxidant enzymes,and reduced lipid ***,pretreatment with betulin alleviated myocardial ischemic damage,as reflected by reduced myonecrosis,edema,and inflammatory ***:Betulin exhibits strong cardioprotective activity against ISO-induced myocardial injury by anti-inflammatory,anti-apoptotic,and antioxidant activities.

关键词： NF-κB Isoproterenol Betulin Myocardial injury Oxidative stress Inflammation Apoptosis