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A novel Application of Multi-Resonant Dissipative Elastic Metahousing for Bearings

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Acta Mechanica Solida Sinica 2021年第4期34卷 449-465页

作者： Muhammad c.W.Lim n.S.Vyas Department of Architecture and civil Engineering City University of Hong KongKowloonHong Kong SARChina Department of Mechanical Engineering Indian Institute of Technology KanpurKanpur208016India

Bearing as an important machine element is widely used for industrial and automotive *** certain operational speed,bearings induce disturbing vibrations and noises that affect machine service life,productivity and passenger comfort in case of vehicle *** elastic metamaterials have caught considerable attention of scientific community due to their effective medium properties and peculiar dynamic characteristics including frequency bandgaps that can be effectively applied to attenuate and control undesirable vibration and *** a substantial amount of theoretical work for effective medium characteristics and dynamic properties of acoustic/elastic metamaterials has been reported,the practical design and application of these composite structures for real-life engineering problems still remain *** present study intends to investigate a potential application of dissipative elastic metamaterials in controlling the bearing-generated vibration and noises over an ultrawide frequency *** study is based on a simple analytical model together with rigorous finite element numerical *** has been established that the dissipative characteristic of resonant system caused by larger material mismatch broadens the local resonance bandgaps beyond the bounding resonance frequency at the cost of wave *** order to achieve broadband vibration and noise control,multi-resonant composite structures are embedded inside the bearing housing in five different *** reported results revealed the presence of broadband wave attenuation zone distributed from 3 to 52 kHz with consideration of material *** bearing-generated vibration and noises lying inside the wave attenuation zone will be *** feasibility study provides a new concept for the design and application of acoustic/elastic metamaterials in the bearing industry to improve machine service life and to enhance productivity and passenger comfo

关键词： Bearing metahousing Dissipative elastic metamaterials Frequency Local resonance bandgap Vibration attenuation zone

Gastroesophageal reflux disease and severe obesity:Fundoplication or bariatric surgery?

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World Journal of Gastroenterology 2010年第30期16卷 3757-3761页

作者： Vivek n Prachand John c Alverdy center for the Surgical Treatment of Obesity Department of SurgeryUniversity of Chicago Pritzker School of MedicineChicagoIL 60637United States

Increases in the prevalence of obesity and gastroesophageal reflux disease (GERD) have paralleled one another over the past decade, which suggests the possibility of a linkage between these two processes. In both instances, surgical therapy is recognized as the most effective treatment for severe, refractory disease. current surgical therapies for severe obesity include (in descending frequency) Roux-en-Y gastric bypass, adjustable gastric banding, sleeve gastrectomy, and biliopancreatic diversion with duodenal switch, while fundoplication remains the mainstay for the treatment of severe GERD. In several large series, however, the outcomes and durability of fundoplication in the setting of severe obesity are not as good as those in patients who are not severely obese. As such, bariatric surgery has been suggested as a potential alternative treatment for these patients. This article reviews current concepts in the putative pathophysiological mechanisms by which obesity contributes to gastroesophageal reflux and their implications with regards to surgical therapy for GERD in the setting of severe obesity.

关键词： Morbid obesity Gastroesophageal reflux disease Fundoplication Bariatric surgery Gastric bypass Sleeve gastrectomy

Use of Silicon Substituents in the Syntheses of natural and non-natural Molecules

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chinese Journal of chemistry 2005年第8期23卷 1106-1108页

作者： WOnG, Henry n. c. Department of chemistry Institute of Chinese Medicine and Central Laboratory of Institute of Molecular Technology for Drug Discovery and Synthesis The Chinese University of Hong Kong Shatin New TerritoriesHong Kong SAR China

Trimethylsilyl groups have been used in our research as a director as well as a bulky and lipophilic group in our quest for natural and non-natural molecules.

关键词： trimethylsilyl bulky group lipophilic group

Effects of Substrate Temperature and Vacuum Annealing on Properties of ITO Films Prepared by Radio-Frquency Magnetron Sputtering

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chinese Physics Letters 2010年第10期27卷 213-216页

作者： n. Boonyopakorn n. Sripongpun c. Thanachayanont S. Dangtip Department of Physics Mahidol University Bangkok 10400 Thailand national Metal and Materials Technology Klongluang Prathumthani 10120 Thailand center for nanoscience and nanotechnology Mahidol University Bangkok 10400 Thailand

Indium tin oxide （ITO） films were prepared by rf magnetron sputtering under two conditions：（i） at substrate temperature Ts from room temperature （RT） to 350℃ （ii） with additional post-annealing in vacuum at 400℃ for 30 min in comparison of their crystalline structures, and electrical-optical properties of the films deposited. From the experimental results, it is found that, under the first condition, the crystalline structures and the electrical-optical properties of the films are improved with the increasing Ts. Under the other condition, i.e. with the additional post-annealing, the films exhibit higher degree of crystallinities and better electrical-optical properties. Under the two deposition conditions, inter-relation between electrical-optical properties and the crystalline structure is observed clearly. However, even under the same annealing condition, it is observed that improved properties of the films are different, depending on their deposition temperatures, which implies that an initial stage of the ITO film before annealing is an important factor for the film＇s properties improved after annealing. The resistivity of 2.33 × 10-4 Ω·cm can be achieved at Ts of 350℃after annealing.

关键词： InDIUM compounds METALLIc oxides AnnEALInG of metals MAGnETROn sputtering MOLEcULAR structure TEMPERATURE effect RADIO frequency METALS -- Optical properties

The role of deformations and orientations in an alpha ternary fission of Thorium

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nuclear Science and Techniques 2022年第6期33卷 1-8页

作者： A.V.Mahesh Babu n.Sowmya H.c.Manjunatha n.Dhananjaya Department of Physics BMSIT&MAffiliated to VTUBangaloreKarnataka 560064India Department of Physics Government College for WomenKolarKarnataka 563101India

The alpha ternary fission half-lives of thorium isotopes have been studied using the coulomb and proximity potential *** role of the deformation effects and the angle of orientation were included during the evaluation of the total *** combinations were identified using cold valley plots of the driving *** half-lives and yields were evaluated using the penetration *** dependence of the logarithmic half-lives on different angles of orientation was *** evaluated alpha ternary fission yield was compared with that of the available experiments with and without *** half-lives obtained in the present work were compared with those of the available *** alpha ternary fission fragments were identified in the isotopes of *** alpha ternary fission half-lives were compared to the binary fission *** binary fission half-lives are dominant in the ^(209-225)Th nuclei,and the ternary fission half-lives are dominant in the isotopes of the ^(226-238)Th nuclei.

关键词： Alpha ternary fission Yield Half-lives Driving potential

Optical spectroscopy study of charge density wave order in Sr3Rh4Sn13 and(Sr0.5ca0.5)3Rh4Sn13

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Science china(Physics,Mechanics & Astronomy) 2017年第4期60卷 51-56页

作者： W.J.Ban H.E Wang c.W.Tseng c.n.Kuo c.S.Lue n.L.Wang Institute of Physics Chinese Academy of SciencesBeijing 100190China Department of Physics Cheng Kung UniversityTainan 70101China International center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China collaborative Innovation center of Quantum Matter Beijing 100871China

We perform optical spectroscopy measurement on single-crystal samples of Sr3Rh4Sn13 and （Sr0.5ca0.5）3Rh4Sn13. Formation of cDW energy gap was clearly observed for both single-crystal samples when they undergo the phase transitions. The existence of residual Drude components in σ1（ω） below Tcow indicates that the Fermi surface is only partially gapped in the cDW state. The obtained value of 2A/kBTcow is roughly 13 for both Sr3Rh4Sn13 and （Sr0.5ca0.5）3Rh4Sn13 compounds, which is considerably larger than the mean-field value based on the weak-coupling BcS theory. The measurements provide optical evidence for the strong coupling characteristics of the cDW phase transition.

关键词： charge density wave optical spectroscopy intermetallic compounds

Simulation of old open clusters for UVIT on ASTROSAT

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Research in Astronomy and Astrophysics 2015年第10期15卷 1647-1670页

作者： Sindhu n Annapurni Subramaniam Anu Radha c School of Advanced Sciences VIT University Indian Institute of Astrophysics

The Ultra Violet Imaging Telescope （UVIT） is one of the payloads on the first Indian multiwavelength satellite ASTROSAT, which is expected to be launched by the Indian Space Research Organisation （ISRO） in the year 2015. We have per- formed simulations of UV studies of old open clusters for the UVIT. The colour mag- nitude diagrams （cMDs） and spatial appearances have been created using 10 filters associated with the FUV channel （130-180 nm） and nUV channel （200-300 nm） that are available for observations on the UVIT, for the three old open clusters M67, nGc 188 and nGc 6791. The cMDs are simulated for different filter combinations, and they are used to identify the loci of various evolutionary sequences, white dwarfs, blue stragglers, red giants, subgiants, turn off stars and the main sequence of the clus- ters. The present work helps in identifying a potential area of study in the case of these three old open clusters by considering the availability of filters and the detection limits of the instrument. We also recommend filter combinations, which can be used to detect and study the above mentioned evolutionary stages. The simulations and the results presented here are essential for the optimal use of the UVIT for studies of old open clusters.

关键词： (stars:) blue stragglers -- (stars:) Hertzsprung-Russell and c-M diagrams-- (stars:) white dwarfs -- (Galaxy:) open clusters and associations: individual (M67,nGc 188 nGc 6791) -- ultraviolet: stars

A novel Big Data Storage Reduction Model for Drill Down Search

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computer Systems Science & Engineering 2022年第4期41卷 373-387页

作者： n.Ragavan c.Yesubai Rubavathi Department of computer Science and Engineering Francis Xavier Engineering CollegeAnna UniversityTamil NaduIndia

Multi-level searching is called Drill down *** now,no drill down search feature is available in the existing search engines like Google,Yahoo,Bing and *** down search is very much useful for the end user toﬁnd the exact search results among the huge paginated search *** level of drill down search with category based search feature leads to get the most accurate search results but it increases the number and size of theﬁle *** purpose of this manuscript is to implement a big data storage reduction binaryﬁle system model for category based drill down search engine that offers fast multi-levelﬁltering *** basic methodology of the proposed model stores the search engine data in the binaryﬁle system *** verify the effectiveness of the proposedﬁle system model,5 million unique keyword data are stored into a binaryﬁle,thereby analysing the proposedﬁle system with efﬁ*** experimental results are also provided based on real data that show our storage model speed and *** demonstrated that ourﬁle system expansion ratio is constant and it reduces the disk storage space up to 30%with conventional database/ﬁle system and it also increases the search performance for any levels of *** discuss deeply,the paper starts with the short introduction of drill down search followed by the discussion of important technologies used to implement big data storage reduction system in detail.

关键词： Big data drill down search storage reduction model binaryﬁle system

Long-term patterns in Iberian hare population dynamics in a protected area(Doñana national Park)in the southwestern Iberian Peninsula:Effects of weather conditions and plant cover

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Integrative Zoology 2017年第1期12卷 49-60页

作者： Francisco cARRO Ramón c.SORIGUER Doñana Biological Station(cSIc) the Monitoring Team on Natural Resources and Processes of the Doñana Biological Station Ethology and Biodiversity conservation SevillaSpain

The Iberian hare(Lepus granatensis)is a widely distributed endemic species in the Iberian *** improve our knowledge of its population dynamics,the relative abundance and population trends of the Iberian hare were studied in the autumns of 1995-2012 in a protected area(Doñana national Park)by spotlighting in 2 different habitats:marshland and *** average relative abundance was 0.38 hare/km(SD=0.63)in the marshland and 3.6 hares/km(SD=4.09)in *** Iberian hare population exhibited local interannual fluctuations and a negative population trend during the study period(1995-2012).The results suggest that its populations are in *** flooding of parts of the marshland in June,July and October favor hare abundance in the *** abundance in the marshland increases as the flooded surface area increases in *** effects are more pronounced if the rains are early(October)and partially flood the *** contrast,when marsh grasses and graminoids are very high and thick(as measured using the aerial herbaceous biomass[biomass marshland]as a proxy),the abundance of hares decreases dramatically as does the area of the marsh that is flooded(in november).

关键词： Doñana Iberian Peninsula Lepus granatensis population dynamics trends