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deductive way of reasoning about the internet As level topology

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Chinese Physics B 2015年第11期24卷 633-642页

作者： d.vid.szabó Attila Korsi József Bíró András Gulyás High speed Networks Laboratory Budapest University of Technology and Economics MTA-BME Information systems Research Group Budapest University of Technology and Economics MTA-BME Future Internet Research Group Budapest University of Technology and Economics

Our current understanding about the As level topology of the Internet is based on measurements and inductive-type models which set up rules describing the behavior （node and edge dynamics） of the individual Ases and generalize the consequences of these individual actions for the complete As ecosystem using induction. In this paper we suggest a third, deductive approach in which we have premises for the whole As system and the consequences of these premises are determined through deductive reasoning. We show that such a deductive approach can give complementary insights into the topological properties of the As graph. While inductive models can mostly reflect high level statistics （e.g., degree distribution, clustering, diameter）, deductive reasoning can identify omnipresent subgraphs and peering likelihood. We also propose a model, called YEAs, incorporating our deductive analytical findings that produces topologies contain both traditional and novel metrics for the As level Internet.

关键词： internet topology complex network analysis model

strategies in training deep learning models to extract building from multisource images with small training sample sizes

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International Journal of digital Earth 2023年第1期16卷 1707-1724页

作者： dávid Abriha szilárd szabó department of Physical Geography and Geoinformatics Faculty of Science and TechnologyUniversity of DebrecenDebrecenHungary

Building extraction from remote sensing data is an important topic in urban studies and the deep learning methods have an increasing role due to their minimal requirements in training data to reach outstanding *** aimed to investigate the original U-Net architecture’s efficiency in building segmentation with different number of training images and the role of data augmentation based on multisource remote sensing data with varying spatial and spectral resolutions(WorldView-2[WV2],WorldView-3[WV3]images and an aerial orthophoto[ORTHO]).When the trainings and predictions were conducted on the same image,U-Net provided good results with very few training images(validation accuracies:94-97%;192 images).Combining the ORTHO’s and WV2’s training data for prediction on WV3 provided poor results with low F1-score(0.184).However,the inclusion of only 48 WV3 training images significantly improved the F1-score(0.693),thus,most buildings were correctly ***,using only independent reference data(other than the target image)is not enough to train an accurate *** our case,the reference from WW2 and ORTHO images did not provide an acceptable basis to train a good model,but a minimal number of training images from the targeted WV3 improved the accuracy(F1-score:69%).

关键词： Building segmentation U-Net remote sensing urban analysis

Joins of 1-Planar Graphs

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Acta Mathematica sinica,English series 2014年第11期30卷 1867-1876页

作者： Július CZAP dvid HUdK Tom MAdARAs department of Applied Mathematics and Business Informatics Faculty of Economics Technical University of KoiceNěmcovej 32040 01 KoiceSlovakia VsL software a.s.Lomen 8040 01 KoiceSlovakia Institute of Mathematics Faculty of SciencePavol Jozef afrik University Jesenn 5040 01 KoiceSlovakia

A graph is called 1-planar if it admits a drawing in the plane such that each edge is crossed at most *** this paper,we study 1-planar graph *** prove that the join G ＋ H is 1-planar if and only if the pair [G,H] is subgraph-majorized by one of pairs [C3 ∪ C3,C3],[C4,C4],[C4,C3],[K2,1,1,P3] in the case when both elements of the graph join have at least three *** one element has at most two vertices,then we give several necessary/sufficient conditions for the bigger element.

关键词： 1-Planar graph join product

2-d eddy resolving simulations of flow past a circular array of cylindrical plant stems

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Journal of Hydrodynamics 2018年第2期30卷 317-335页

作者： Kyoungsik Chang George constantinescu sanghyun Park school of Mechanical Engineering Ulsan University Ulsan Korea Civil and Environmental Engineering department IIHR-Hydroscience and Engineering Stanley Hydraulics Laboratory The University of Iowa Iowa City USA Korea Aerospace Research Institute Daejeon Korea

In the present study, 2-d large eddy simulations（LEs） are conducted for flow past a porous circular array with a solid volume fraction（sVF） of 8.8%, 15.4% and 21.5%. such simulations are relevant to understanding flow in natural streams and channels containing patches of emerged vegetation. In the simulations discussed in the paper, the porous cylinder of diameter d contains a variable number of identical solid circular cylinders（rigid plant stems） of diameter d= 0.048 d. Most of the simulations are conducted at a Reynolds number of 2 100 based on the diameter d and the velocity of the steady uniform incoming flow. Though in all cases wake billows are shed in the regions where the separated shear layers（ssLs） forming on the sides of the porous cylinder interact, the effect of these wake billows on the mean drag is different. While in the high sVF case（21.5%）, the total drag force oscillates quasi-regularly in time, similar to the canonical case of a large solid cylinder, in the cases with a lower sVF the shedding of the wake billows takes place sufficiently far from the cylinder such that the unsteady component of the total drag force is negligible. The mean amplitude of the oscillations of the drag force on the individual cylinders is the largest in a streamwise band centered around the center of the porous cylinder, where the wake to wake interactions are the strongest. In all cases the maximum drag force on the individual cylinders is the largest for the cylinders directly exposed to the flow, but this force is always smaller than the one induced on a small isolated cylinder and the average magnitude of the force on the cylinders directly exposed to the flow decreases monotonically with the increase in the sVF. Predictions of the global drag coefficients, strouhal numbers associated with the wake vortex shedding and individual forces on the cylinders in the array from the present LEs are in very good agreement with those of 2-d direct numerical simulations conduc

关键词： Vegetation eddy resolving simulation solid volume fraction porous cylinder bleeding flow

Hyperactive learning for data-driven interatomic potentials

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npj Computational Materials 2023年第1期9卷 599-612页

作者： Cas van der Oord Matthias sachs dávid Péter Kovács Christoph Ortner Gábor Csányi University of Cambridge Cambridge CB21PZUK University of Birmingham Birmingham B152TTUK University of British Columbia VancouverBC V6T 1Z2Canada

data-driven interatomic potentials have emerged as a powerful tool for approximating ab initio potential energy *** most time-consuming step in creating these interatomic potentials is typically the generation of a suitable training *** aid this process hyperactive learning(HAL),an accelerated active learning scheme,is presented as a method for rapid automated training database *** adds a biasing term to a physically motivated sampler(*** dynamics)driving atomic structures towards uncertainty in turn generating unseen or valuable training *** proposed HAL framework is used to develop atomic cluster expansion(ACE)interatomic potentials for the Alsi10 alloy and polyethylene glycol(PEG)polymer starting from roughly a dozen initial *** HAL generated ACE potentials are shown to be able to determine macroscopic properties,such as melting temperature and density,with close to experimental accuracy.

关键词： starting generating consuming

Network meta-analysis of randomized controlled trials on esophagectomies in esophageal cancer:The superiority of minimally invasive surgery

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World Journal of Gastroenterology 2022年第30期28卷 4201-4210页

作者： Lajos szakó dávid Németh Nelli Farkas szabolcs Kiss Réka Zsuzsa domotor Marie Anne Engh Péter Hegyi Balint Eross András Papp Institute of Translational Medicine University of PécsMedical SchoolPécs 7624Hungary János szentágothai Research Centre University of PécsMedical SchoolPécs 7624Hungary Institute for Translational Medicine University of PécsMedical SchoolPécs 7624Hungary of Bioanalysis University of PécsMedical SchoolPécs 7624Hungary Insittute of Translational Medicine University of PécsMedical SchoolPécs 7624Hungary doctoral school of Clinical Medicine University of SzegedMedical SchoolSzeged 6720Hungary First department of Medicine University of SzegedMedical SchoolSzeged 6725Hungary Institute of Translational Medicine University of PecsMedical SchoolPecs 7624Hungary department of surgery Clinical CenterUniversity of PécsMedical SchoolPécs 7624Hungary

BACKGROUNd Previous meta-analyses,with many limitations,have described the beneficial nature of minimal invasive *** To compare all modalities of esophagectomies to each other from the results of randomized controlled trials(RCTs)in a network meta-analysis(NMA).METHOds We conducted a systematic search of the MEdLINE,EMBAsE,Reference Citation Analysis(https://***/)and CENTRAL databases to identify RCTs according to the following population,intervention,control,outcome(commonly known as PICO):P:Patients with resectable esophageal cancer;I/C:Transthoracic,transhiatal,minimally invasive(thoracolaparoscopic),hybrid,and robot-assisted esophagectomy;O:survival,total adverse events,adverse events in subgroups,length of hospital stay,and blood *** used the Bayesian approach and the random effects *** presented the geometry of the network,results with probabilistic statements,estimated intervention effects and their 95% confidence interval(CI),and the surface under the cumulative ranking curve to rank the *** We included 11 studies in our *** found a significant difference in postoperative pulmonary infection,which favored the minimally invasive intervention compared to transthoracic surgery(risk ratio 0.49;95%CI:0.23 to 0.99).The operation time was significantly shorter for the transhiatal approach compared to transthoracic surgery(mean difference-85 min;95%CI:-150 to-29),hybrid intervention(mean difference-98 min;95%CI:-190 to-9.4),minimally invasive technique(mean difference-130 min;95%CI:-210 to-50),and robot-assisted esophagectomy(mean difference-150 min;95%CI:-240 to-53).Other comparisons did not yield significant *** Based on our results,the implication of minimally invasive esophagectomy should be favored.

关键词： surgery Esophageal cancer Esophagectomy Network meta-analysis Minimally invasive Laparoscopy

Female answer specificity to male drumming calls in three closely related species of the stonefly genus Zwicknia (Plecoptera: Capniidae)

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Insect science 2021年第1期28卷 215-223页

作者： Kirill Mark Orci david Muranyi MTA-ELTE-MTM Ecology Research Group Hungarian Academy of SciencesEotvos Lorand University and the Hungarian Natural History MuseumBudapestHungary department of Zoology Eszterhazy Karoly UniversityEgerHungary department of Zoology Hungarian Natural History MuseumBudapestHungary

This study examines the rate of female answers to conspecific versus heterospecific male vibratory calls in three,closely related stonefly species:Zwicknia bifrons,***,and *** a previous study those three species were recognized on the basis of their distinct male drumming calls along with differences in genital morphology and genetic *** this study no-choice playback experiments using original male call samples from each species were performed,and the answer rate of females to con・specific and heterospecific signal variants was *** effect logistic regression models were used to test if male call species identity had a statistically significant effect on female answer *** answered conspecific male calls with significantly higher probability than heterospecific calls in all the three examined species,suggesting that the divergence of vibrational communication can be an important component of the prezygotic isolation between ***,but well detectable responsiveness to heterospecific calls was observable between *** and ***,the two species closest to each other regarding mitochondrial genetic divergence and male call pattern ***,our results are most congruent with a tight,gradual coevolution of male calls and female preferences.

关键词： biotremology drumming call Plecoptera reproductive isolation species recognition vibrational communication

Calcium pyrophosphate dihydrate crystals in a 9-year-old with osteomyelitis of the knee:A case report

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World Journal of Orthopedics 2022年第9期13卷 870-875页

作者： William Pavlis d.vid.s constantinescu Rajan Murgai spencer Barnhill Brian Black department of Orthopaedics University of MiamiMiami33136United States

BACKGROUNd Calcium pyrophosphate dihydrate deposition disease(CPPd),or pseudogout,is an inflammatory arthritis common among elderly patients,but rarely seen in patients under the age of *** the rare cases presented of young patients with CPPd,genetic predisposition or related metabolic conditions were almost always *** sUMMARY The authors report the case of a 9-year-old boy with no past medical history who presented with acute knee pain and swelling after a cat scratch injury 5 d *** fluid analysis identified calcium pyrophosphate dihydrate *** MRI analysis identified osteomyelitis and a small soft tissue *** This case presents the extremely rare diagnostic finding of calcium pyrophosphate dihydrate crystals in a previously healthy pediatric *** presence of osteomyelitis presents a unique insight into the pathogenesis of these crystals in pediatric *** research needs to be done on the role of CPPd in pediatric arthritis and joint infection.

关键词： Calcium pyrophosphate Pseudogout Pediatrics Crystals Osteomyelitis Case report

default or profit scoring credit systems?Evidence from European and Us peer-to-peer lending markets

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Financial Innovation 2022年第1期8卷 954-974页

作者： Štefan Lyócsa Petra Vašaničová Branka Hadji Misheva Marko dávid Vateha Faculty of Management and Business University of PrešovPrešovSlovak Republic Institute of Economic Research Slovak Academy of SciencesBratislavaSlovak Republic ZHAW school of Engineering WinterthurSwitzerland depart-ment of Banking and International Finance Faculty of National EconomyUniversity of Economics in BratislavaBratislavaSlovak Republic Faculty of Economics and Administration Masaryk UniversityLipová507/41a60200 BrnoCzech Republic

For the emerging peer-to-peer(P2P)lending markets to survive,they need to employ credit-risk management practices such that an investor base is profitable in the long ***,credit-risk management relies on credit scoring that predicts loans’probability of *** this paper,we use a profit scoring approach that is based on modeling the annualized adjusted internal rate of returns of *** validate our profit scoring models with traditional credit scoring models,we use data from a European P2P lending market,Bondora,and also a random sample of loans from the Lending Club P2P lending *** compare the out-of-sample accuracy and profitability of the credit and profit scoring models within several classes of statistical and machine learning models including the following:logistic and linear regression,lasso,ridge,elastic net,random forest,and neural *** found that our approach outperforms standard credit scoring models for Lending Club and Bondora *** specifically,as opposed to credit scoring models,returns across all loans are 24.0%(Bondora)and 15.5%(Lending Club)higher,whereas accuracy is 6.7%(Bondora)and 3.1%(Lending Club)higher for the proposed profit scoring ***,our results are not driven by manual selection as profit scoring models suggest investing in more ***,even if we consider data sampling bias,we found that the set of superior models consists almost exclusively of profit scoring ***,our results contribute to the literature by suggesting a paradigm shift in modeling credit-risk in the P2P market to prefer profit as opposed to credit-risk scoring models.

关键词： Profit scoring Credit scoring Financial intermediation P2P Fintech