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Optimized CUDA Implementation to Impr.ve the Per.or.ance of Bundle Adjustment Algor.thm on GPUs

Jour.al of Softwar. Engineer.ng and Applications 2024年第4期17卷 172-201页

作者： Pr.nay r. Kommer. Sur.sh S. Muknahallipatna John E. McInr.y Depar.ment of Electr.cal Engineer.ng and Computer.Science University of Wyoming Laramie Wyoming USA

The 3D r.constr.ction pipeline uses the Bundle Adjustment algor.thm to r.fine the camer. and point par.meter.. The Bundle Adjustment algor.thm is a compute-intensive algor.thm, and many r.sear.her. have impr.ved its per.or.ance by implementing the algor.thm on GPUs. In the pr.vious r.sear.h wor., “Impr.ving Accur.cy and Computational Bur.en of Bundle Adjustment Algor.thm using GPUs,” the author. demonstr.ted fir.t the Bundle Adjustment algor.thmic per.or.ance impr.vement by r.ducing the mean squar. er.or.using an additional r.dial distor.ing par.meter.and explicitly computed analytical der.vatives and r.ducing the computational bur.en of the Bundle Adjustment algor.thm using GPUs. The naïve implementation of the CUDA code, a speedup of 10× for.the lar.est dataset of 13,678 camer.s, 4,455,747 points, and 28,975,571 pr.jections was achieved. In this paper. we pr.sent the optimization of the Bundle Adjustment algor.thm CUDA code on GPUs to achieve higher.speedup. We pr.pose a new data memor. layout for.the par.meter. in the Bundle Adjustment algor.thm, r.sulting in contiguous memor. access. We demonstr.te that it impr.ves the memor. thr.ughput on the GPUs, ther.by impr.ving the over.ll per.or.ance. We also demonstr.te an incr.ase in the computational thr.ughput of the algor.thm by optimizing the CUDA ker.els to utilize the GPU r.sour.es effectively. A compar.tive per.or.ance study of explicitly computing an algor.thm par.meter.ver.us using the Jacobians instead is pr.sented. In the pr.vious wor., the Bundle Adjustment algor.thm failed to conver.e for.cer.ain datasets due to sever.l block matr.ces of the camer.s in the augmented nor.al equation, r.sulting in r.nk-deficient matr.ces. In this wor., we identify the camer.s that cause r.nk-deficient matr.ces and pr.pr.cess the datasets to ensur. the conver.ence of the BA algor.thm. Our.optimized CUDA implementation achieves conver.ence of the Bundle Adjustment algor.thm in ar.und 22 seconds for.the lar.est dataset compar.d

关键词： Scene r.constr.ction Bundle Adjustment Levenber.-Mar.uar.t Non-Linear.Least Squar.s Memor. Thr.ughput Computational Thr.ughput Contiguous Memor. Access CUDA Optimization

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Cor.osion and Scaling Thr.at in Upstr.am Oil Oper.tion

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Wor.d Jour.al of Engineer.ng and Technology 2024年第2期12卷 426-437页

作者： Nasir.Ullattumpoyil Talal M. Al-Ghamdi Nasser.r. Al-Hajr. Souther. Ar.a Technical Suppor. Depar.ment Saudi Aramco Dhahran KSA

Cor.osiveness or.scaling is an inher.nt thr.at to oil oper.tions. The pr.mar. cause for.this thr.at is the pr.sence of water.having complex geochemical matr.x. Unanticipated water.pr.duction, par.icular.y if it contains unwanted impur.ties, can significantly impact hydr.car.on pr.duction. The cur.ent paper.discusses the degr.e of thr.at posed to oil oper.tion facilities based on the water.char.cter.stics. Methodology involved the collection and analysis of water.samples fr.m major.sour.es in oil industr. such as gr.undwater. wellheads and seawater. The par.meter. tested include geochemical, micr.biological and pollutants. The lab data was used to develop scaling and cor.osion pr.diction indices such as Langelier.Satur.tion Index (LSI), r.znar.Stability Index (r.I) and Puckor.us Scaling Index (PSI). The study indicated var.ing water.chemistr. for.differ.nt sour.es. Mixing of those water. may lead to ionic satur.tion and scaling in differ.nt facilities. Pr.sence of the Sr. and GAB in some water.sour.es also posed thr.at to water.system by for.ing fouling and cor.osion. Seawater.used for.offshor. oilfields water.injection to maintain r.ser.oir.pr.ssur. and impr.ve oil r.cover. showed scaling tendency, wher.as under.differ.nt r.ser.oir.pr.ssur., it can cause cor.osion. Some of the samples also had cor.osion r.siduals such as ir.n, which indicated active cor.osion. Cur.ent study showed higher.alkalinity with high sulfate for.one gr.undwater.sample with pr.sence of active cor.osion r.siduals such as dissolved ir.n and manganese. The study showed positive value for.LSI which indicated super.atur.tion of the water.samples with r.spect to calcium car.onate (CaCO3) and scale for.ing. Similar.y, for.r.I and PSI, the value was below six which confir.ed the scaling potential for.all the samples. Even though the index value was pointing towar.s scaling potential, the geochemistr., micr.biology and pr.sence of other.impur.ties indicated cor.osion thr.at to the oil and g

关键词： For.ation Water Petr.leum r.ser.oir. Gr.undwater Satur.tion Indices Cor.osiveness

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Fetal Head Compr.ssion: Its Possible r.le in Neur.logic Injur.

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Open Jour.al of Obstetr.cs and Gynecology 2024年第1期14卷 124-143页

作者： Bar.y S. Schifr.n Br.an J. Koos Wayne r. Cohen Depar.ment of Obstetr.cs and Gynecology The Western University of Health Sciences Pomona USA The David Geffen School of Medicine at UCLA Los Angeles USA The Univer.ity of Ar.zona College of Medicine Tucson USA

It is widely assumed that fetal ischemic br.in injur. dur.ng labor.der.ves almost exclusively fr.m sever., systemic hypoxemia with mar.ed neonatal depr.ssion and acidemia. Sever. asphyxia, however. is one of sever.l causes of per.natal neur.logical injur. and may not be the most common;most neonates diagnosed with hypoxic-ischemic encephalopathy do not have evidence of sever. asphyxia. Sepsis, dir.ct br.in tr.uma, and dr.g or.toxin exposur. account for.some cases, while mechanical for.es of labor.and deliver. that incr.ase fetal intr.cr.nial pr.ssur. sufficiently to impair.br.in per.usion may also contr.bute. Because of bony compliance and mobile sutur. lines, the fetal skull changes shape and r.distr.butes cer.br.spinal fluid dur.ng labor.accor.ing to constr.ints imposed by contr.ctions, and bony and soft tissue elements of the bir.h canal as the head descends. These accommodations, including the incr.ase in intr.cr.nial pr.ssur., ar. adaptive and necessar. for.efficient descent of the head while safeguar.ing cer.br.l blood flow. Autonomic r.flexes mediated thr.ugh centr.l r.ceptor. nor.ally pr.vide ample pr.tection of the br.in fr.m the consider.ble pr.ssur. exer.ed on the skull. On occasion, those for.es, which ar. tr.nsmitted intr.cr.nially, may over.ome the var.ous adaptive anatomical, car.iovascular. metabolic, and neur.logical mechanisms that maintain cer.br.l per.usion and oxygen availability, r.sulting in ischemic br.in injur.. Accepting the notion of a potentially adver.e impact of fetal head compr.ssion suggests that avoidance of excessive uter.ne activity and of r.lentless pushing without steady pr.gr.ss in descent may offer.pr.tection for.the fetal br.in dur.ng par.ur.tion. Excessive head compr.ssion should be consider.d in the differ.ntial diagnosis of ischemic encephalopathy.

关键词： Fetal Br.in Injur. Fetal Head Compr.ssion Ischemic Encephalopathy Neonatal Encephalopathy

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Heat and Mass Tr.nsfer.for.a Nanofluid Flow in Fluidized Bed Dr.er.in Pr.sence of Induced Magnetic Field

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Jour.al of Applied Mathematics and Physics 2024年第4期12卷 1401-1425页

作者： Kiptum J. Pur.ty Mathew N. Kinyanjui Edwar. r. Onyango Pan Afr.can Univer.ity Institute for.Basic Sciences Technology and Innovation Nairobi Kenya Depar.ment of Pur. and Applied Mathematics Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya

This r.sear.h entails the study of heat and mass tr.nsfer.of nanofluid flow in a fluidized bed dr.er.used in tea dr.ing pr.cesses in pr.sence of induced magnetic field. A mathematical model descr.bing the fluid flow in a Fluidized bed dr.er.was developed using the nonlinear.par.ial differ.ntial equations. Due to their.non-linear.ty, the equations wer. solved numer.cally by use of the finite differ.nce method. The effects of physical flow par.meter. on velocity, temper.tur., concentr.tion and magnetic induction pr.files wer. studied and r.sults wer. pr.sented gr.phically. Fr.m the mathematical analysis, it was deduced that addition of silver.nanopar.icles into the fluid flow enhanced velocity and temper.tur. pr.files. This led to impr.ved heat tr.nsfer.in the fluidized bed dr.er. hence amplifying the tea dr.ing pr.cess. Fur.her.or., it was noted that induced magnetic field tends to decr.ase the fluid velocity, which r.sults in unifor. distr.bution of heat leading to efficient heat tr.nsfer.between the tea par.icles and the fluid, thus impr.ving the dr.ing pr.cess. The r.sear.h findings pr.vide infor.ation to industr.es on ways to optimize ther.al per.or.ance of fluidized bed dr.er..

关键词： Heat Tr.nsfer Induced Magnetic Field Nanofluid Fluidized Bed Dr.er

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Black Gar.ic as an Antivir.l for.Her.es Simplex Vir.s-2 in Lung Cells

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Advances in Bioscience and Biotechnology 2024年第1期15卷 70-89页

作者： Jenna r. Hor.witz Lee H. Lee Sandr. D. Adams Depar.ment of Biology Montclair State University Montclair NJ USA

Allicin, an antioxidant, is known for.pr.viding gar.ic with its unique fr.gr.nce and taste, as well as for.its antimicr.bial pr.per.ies. Black gar.ic, a fer.ented for. of gar.ic, contains higher.levels of antioxidants than fr.sh gar.ic. Antioxidants play a vital r.le in alleviating cellular.str.ss dur.ng vir.l infections. Vir.l infections r.sult in oxidative str.ss thr.ugh the pr.duction of r.active oxidative species (r.S). A pr.longed state of oxidative str.ss can r.sult in cell death, DNA damage, and disease pr.gr.ssion. In this study, black gar.ic extr.ct (BGE) is evaluated for.its ability to mitigate cytopathic effects and oxidative str.ss caused by her.es simplex vir.s-2 (HSV-2) infections in vitr.. Antivir.l assays wer. per.or.ed to deter.ine the per.ent of vir.l inhibition r.sulting fr.m tr.atment with the BGE. r.S-GloTM H2O2 assays wer. then completed to measur. the post-infection r.S levels of BGE-tr.ated vir.s and cells. The r.sults thus far.suggest that BGE may inhibit vir.l infection and decr.ase levels of oxidative str.ss.

关键词： Black Gar.ic Her.es Simplex Vir.s-2 Antioxidant Antivir.l Allicin

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COVID-19-r.lated chemosensor. changes:Findings fr.m a pr.spective national database

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Wor.d Jour.al of Otor.inolar.ngology-Head and Neck Sur.er. 2024年第2期10卷 97-104页

作者： Mihai A.Bentan Evan r.r.iter.r.char. M.Costanzo Daniel H.Coelho Depar.ment of Otolar.ngology-Head&Neck Sur.er. Virginia Commonwealth University School of MedicineRichmondVirginiaUSA

Objective:The aim of this study was to r.view findings fr.m a lar.e pr.spective national database of chemosensor. distur.ances associated with cor.navir.s disease 2019(COVID-19)*** Sour.es:The Vir.inia Commonwealth Univer.ity Smell and Taste Center.national database of COVID-19 chemosensor. ***:A ser.es of online sur.eys,fir.t opened on Apr.l 10,2020,was made accessible nationwide to any adult with sudden chemosensor. dysfunction since Januar. *** r.ceived subsequent follow-up sur.eys 14 days,1 month,3 months,and 6 months after.*** additional sur.ey was sent to all par.icipants on May 28,2022 to assess long-ter. *** per.aining to demogr.phics,symptoms,comor.idities,tr.atments,and life impact was ***:Of 363 par.icipants who r.por.ed complete smell r.cover.,51.2%r.cover.d within 1 month,70%within 3 months,and 79%within 6 months,while 8.8%took over.1 year.to completely *** all par.icipants,7.5%had no smell *** pr.dictor. of r.cover. included ager.and the pr.sence of nasal *** pr.dictor. included difficulty br.athing and pr.or.head *** par.icipants r.por.ed a decr.ase in quality of life and the pr.sence of potential safety hazar.s associated with decr.ased smell ***:Most subjects with COVID-19-r.lated chemosensor. dysfunction r.cover.with the major.ty noting complete r.cover. within weeks of *** aged over.40 year. and female gender.wer. associated with lower.r.tes of r.cover..A consider.ble number.of par.icipants r.por.ed significant impact on quality of life and safety.

关键词： anosmia COVID-19 smell

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Simple collective model for.nuclear.chir.l mode

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Fr.ntier. of physics 2024年第2期19卷 1-5页

作者： r.V.Jolos E.A.Kolganova D.r.Khamitova Joint Institute for.Nuclear.r.sear.h 141980 DubnaMoscow regionRussia Dubna State Univer.ity 141982 DubnaMoscow RegionRussia

A simple semi-analytical collective model that takes into account the limitations of the var.ation inter.al of the collective var.able is suggested to descr.be the chir.l dynamics in tr.axial odd−odd nuclei with a fixed par.icle−hole *** collective Hamiltonian is constr.cted with the potential ener.y obtained using the postulated ansatz for.the wave function symmetr.c with r.spect to chir.l *** diagonalizing the collective Hamiltonian the wave functions of the lowest states ar. obtained and the evolution of the ener.y splitting of the chir.l doublets in tr.nsition fr.m chir.l vibr.tion to chir.l r.tation r.gime is demonstr.ted.

关键词： collective model nuclear chir.l

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Sex-specific life-histor. tr.it expr.ssion in hybr.ds of a cave- and sur.ace-dwelling fish (Poecilia mexicana, Poecilidae)

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Cur.ent Zoology 2024年第4期70卷 421-429页

作者： r.diger.r.esch Luis r.Ar.iaga Ingo Schlupp Depar.ment of Biological Sciences Royal Holloway University of LondonEghamTW20 OEXUK CEFE CNRSUnivMontpellierEPHEIRDMontpellierFrance Depar.ment of Biology University of OklahomaNormanOK 73019USA

Evaluating the fitness of hybr.ds can pr.vide impor.ant insights into genetic differ.nces between species or.diver.ing *** focused on sur.ace-and cave-ecotypes of the widespr.ad Atlantic molly Poecilia mexicana and r.ised F1 hybr.ds of r.cipr.cal cr.sses to sexual matur.ty in a common-gar.en *** wer. r.ar.d in a fully factor.al 2 x 2 design consisting of lighting(light ***)and r.sour.e availability(high *** food).We quantified sur.ival,ability to r.alize their.full r.pr.ductive potential(i.e.,completed matur.tion for.males and 3 consecutive bir.hs for.females)and essential life-histor. *** to the per.or.ance of pur. cave and sur.ace fish fr.m a pr.vious exper.ment,F1s had the highest death r.te and the lowest pr.por.ion of fish that r.ached their.full r.pr.ductive *** also uncover.d an intr.guing patter. of sex-specific phenotype expr.ssion,because male hybr.ds expr.ssed cave molly life histor.es,while female hybr.ds expr.ssed sur.ace molly life *** r.sults pr.vide evidence for.str.ng selection against hybr.ds in the cave molly system,but also sug-gest a complex patter. of sex-specific(opposing)dominance,with cer.ain sur.ace molly genes being dominant in female hybr.ds and cer.ain cavemollygenes beingdominant in malehybr.ds.

关键词： dominance life-histor. evolution local adaptation postzygotic isolation selection against hybr.ds.

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Changes in snow cover.extent in the Centr.l Taur.s Mountains fr.m 1981 to 2021 in r.lation to temper.tur., pr.cipitation, and atmospher.c teleconnections

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Jour.al of Mountain Science 2024年第1期21卷 49-67页

作者： Ecmel Er.AT Fulya AYDIN-KANDEMİr Depar.ment of Geogr.phy Ege UniversityIzmir 35100Türkiye Climate Change and Zer. Waste Depar.ment Antalya Metropolitan MunicipalityAntalya 07310Türkiye Hydr.politics Association Ankara 06680Türkiye

The snow cover.over.the Taur.s Mountains affects water.supply, agr.cultur., and hydr.power.gener.tion in the r.gion. In this study, we analyzed the monthly Snow Cover.Extent(SCE) fr.m November.to Apr.l in the Centr.l Taur.s Mountains(Bolkar. Aladaglar. Tahtali and Binboga Mountains) fr.m 1981 to 2021. Linear.tr.nds of snow cover.season(November.to Apr.l) over.the last 41 year. showed decr.ases in SCE pr.mar.ly at lower.elevations. The downwar. tr.nd in SCE was found to be mor. pr.nounced and statistically significant for.only November.and Mar.h. SCE in the Centr.l Taur.s Mountains has declined about-6.3% per.decade for.2500-3000 m in November.and about-6.0% per.decade for.1000-1500 m and 3000+ m in Mar.h over.the last 41 year.. The loss of SCE has become evident since the 2000s, and the lowest negative anomalies in SCE have been obser.ed in 2014, 2001, and 2007 in the last 41 year., which ar. consistent with an incr.ase in air.temper.tur. and decr.ased pr.cipitation. SCE was cor.elated with both mean temper.tur. and pr.cipitation, with temper.tur. having a gr.ater.r.lative impor.ance at all elevated gr.dients. r.sults showed that ther. is a str.ng linear.r.lationship between SCE and the mean air.temper.tur.(r.=-0.80) and pr.cipitation(r.= 0.44) for.all elevated gr.dients dur.ng the snow season. The Ar.tic Oscillation(AO), the Nor.h Atlantic Oscillation(NAO), and the Mediter.anean Oscillation(MO) winter.indices wer. used to explain the year.to-year.var.ability in SCE over.the Centr.l Taur.s Mountains. The r.sults showed that the inter.annual var.ability obser.ed in the winter.SCE on the Centr.l Taur.s Mountains was positively cor.elated with the phases of the winter.AO, NAO and MO, especially below 2000 m elevation.

关键词： Snow cover.extent Atmospher.c teleconnection Centr.l Taur.s Mountains Air.temper.tur. and pr.cipitation Geogr.phic Infor.ation Systems Tür.iye

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另类的白肉

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商业周刊（中文版） 2024年第3期 68-73页

作者： Deena Shanker.Pr.ya anand 王湛(译) 不详

Upside Foods等硅谷支持的初创公司承诺通过实验室培养鸡肉来解决肉类问题然而这一解决方案似乎不太靠谱,10年前,在伦敦的一场新闻发布会上,一位荷兰科学家、一位芝加哥美食作家和一位奥地利的研究人员分享了一块价值33万美元的牛肉饼... 详细信息

Upside Foods等硅谷支持的初创公司承诺通过实验室培养鸡肉来解决肉类问题然而这一解决方案似乎不太靠谱,10年前,在伦敦的一场新闻发布会上,一位荷兰科学家、一位芝加哥美食作家和一位奥地利的研究人员分享了一块价值33万美元的牛肉饼。这块汉堡代表了全世界对实验室培养肉类最认真的尝试,通过从牛身上提取细胞并在实验室中培养制作而成。(此前曾有过为宇航员提供金鱼肉片的实验,以及把青蛙牛排制成“生物艺术品”的尝试。)荷兰科学家兼教授马克·波斯特(Mar.Post)花了六周时间,在培养皿和试管中培养出2万根肌肉纤维。完成后,这些细小的肌肉组织被手工取出,压制成一块汉堡。

关键词：肌肉纤维初创公司实验室培养牛肉饼肌肉组织牛排新闻发布会鸡肉

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