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Journal of Forestry Research 2017年第5期28卷 1049-1059页

作者： Róbert Smreek Ivan Sakov Zuzana Michnová Ján Tuek Department of Forest Management and Geodesy Technical University in Zvolen Department of Forest Policy Economics and Forest ManagementNational Forest Centre-Forest Research Institute Zvolen

Identifying tree locations is a basic step in the derivation of other tree parameters using remote sensing techniques, particularly when using airborne laser scanning. There are several techniques for identifying tree positions. In this paper, we present a raster-based method for determining tree position and delineating crown coverage. We collected data from nine research plots that supported different mixes of species. We applied a raster-based method to raster layers with six different spatial resolutions and used terrestrial measurement data as reference data. Tree identification at a spatial resolution of 1.5 m was demonstrated to be the most accurate, with an average identification ratio (IR) of 95% and average detection ratio of 68% being observed. At a higher spatial resolution of 0.5 m, IR was overestimated by more than 600%. At a lower spatial resolution of 3 m, IR was underestimated at less than 44% of terrestrial measurements. The inventory process was timed to enable evaluation of the time efficiency of automatic methods.

关键词： Airborne laser scanning East-Central Europe Individual tree Mixed forest Tree crown delineation

ON CLASSES OF REGULAR GRAPHS WITH CONStaNT METRIC DIMENSION

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Acta Mathematica Scientia 2013年第1期33卷 187-206页

作者： Muhammad IMRAN Syed Ahtsham ul Haq BOKHARY Ali AHMAD Andrea SEMANIOV-FENOVíkov Centre for Advanced Mathematics and Physics(CAMP) National University of Sciences and Technology(NUST) Center for Advanced Studies in Pure and Applied Mathematics Bahauddin Zakariya University College of Computer and Information System Jazan University Department of Applied Mathematics and Informatics Technical University

In this paper, we are dealing with the study of the metric dimension of some classes of regular graphs by considering a class of bridgeless cubic graphs called the flower snarks Jn, a class of cubic convex polytopes considering the open problem raised in [M. Imran et al., families of plane graphs with constant metric dimension, Utilitas Math., in press] and finally Harary graphs H5,n by partially answering to an open problem proposed in Ⅱ. Javaid et al., Families of regular graphs with constant metric dimension, Utilitas Math., 2012, 88： 43-57]. We prove that these classes of regular graphs have constant metric dimension.

关键词： metric dimension basis resolving set cubic graph flower snark convexpolytope

微弧氧化法制备钛基HA/CS涂层及其生物学特性

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稀有金属材料与工程 2013年第12期42卷 2586-2589页

作者：王国卿 Zver'kov D A 张乃生东北大学辽宁沈阳110004 莫斯科国立兽医与生物技术学院莫斯科109472 吉林大学吉林长春130062

采用微弧氧化法在医用钛表面制备羟基磷灰石(HA)/壳聚糖(CS)涂层。通过扫描电镜(SEM)、X射线衍射(XRD)仪、红外光谱(FTIR)仪分析涂层的形貌和物相,评价HA/CS涂层对成骨细胞的毒性及其在动物体内的生物活性,分析微弧氧化法制备钛基HA/CS... 详细信息

采用微弧氧化法在医用钛表面制备羟基磷灰石(HA)/壳聚糖(CS)涂层。通过扫描电镜(SEM)、X射线衍射(XRD)仪、红外光谱(FTIR)仪分析涂层的形貌和物相,评价HA/CS涂层对成骨细胞的毒性及其在动物体内的生物活性,分析微弧氧化法制备钛基HA/CS涂层的特征及其在骨修复中应用的可能性。结果表明:微弧氧化法可在钛表面生成HA/CS涂层,厚度40±2 m、粗糙度3.3±0.1 m、孔隙率(30±2)%,孔隙近圆形、直径几微米到20 m,结合强度20.5±1.1 MPa;涂层中HA与CS之间没有形成化学键,晶体HA占10%,平均粒径37 nm,非晶体HA占90%;钛基HA/CS涂层材料对成骨细胞增殖具有促进作用,无细胞毒性,在动物体内能够诱导骨小梁形成,具有高的生物活性。微弧氧化法制备的高生物活性钛基HA/CS涂层材料,在骨修复方面具有良好的应用前景。

关键词：微弧氧化羟基磷灰石壳聚糖复合涂层钛种植体生物活性

How can stream bank erosion be predicted on small water courses?Veri?cation of BANCS model on the Kubrica watershed

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International Journal of Sediment Research 2021年第3期36卷 419-429页

作者： Zuzana Allmanová Máaria Vl?kováa Martin Jankovsky Michal Allman Jáan Mergani? Department of Forest Harvesting Logistics and Ameliorations Faculty of Forestry Technical University in Zvolen Department of Forestry Technology and Constructions Faculty of Forestry and Wood Sciences Czech University of Life Sciences Prague

The current paper deals with the evaluation of the BANCS erosion prediction model and its two componentsethe Bank Erosion Hazard Index（BEHI） and Near-Bank Stress（NBS） indices. To construct the erosion prediction curves, 18 experimental sections were established on the Kubrica Stream, district of Trencín, Slovakia. Each section was assessed through the NBS index and BEHI index and real annual bank erosion was measured using erosion toe pins. Subsequently, the relations between the BEHI and real annual bank erosion was assessed through regression and correlation analyses. The relation proved to be moderately strong, with the correlation coefficient（R） reaching 0.47. Further, the relation between the NBS index and real annual bank erosion was evaluated, which was also moderately strong, with R= *** on the measured data, two erosion prediction curves were constructed, the first for moderate BEHI, with R= 0.69 and coefficient of determination（R2） of 0.47 and the second for high BEHI with R=0.74 and R2= 0.55. The prediction curves were based on data from one year of measurements and can, therefore, be used only for discharges that occurred within that year and in the region where the model was developed. In the current case, according to runoff Curve Numbers（CN）, the real culmination discharge was Q ? 1.88 m3/s, which is roughly equivalent to 1.5-year recurrence interval flow（Q1.5）.

关键词： Bank erosion Bank assessment for non-point source consequences of sediment (BANCS) Bank erosion hazard index Near-bank stress index Erosion prediction curves

Role of forests in headwater control with changing environment and society

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International Soil and Water Conservation Research 2021年第1期9卷 143-157页

作者： Josef Krecek Jana Nováková Ladislav Palán Eva Pazourková Evzen Stuchlík Department of Hydrology Czech Technical University in PragueThákurova 7CZ-16629Prague 6Czech Republic Independent Botanist Na Vrcholu 4CZ-13000PragueCzech Republic AON Impact Forecasting Václavskénáměstí19CZ-11000PragueCzech Republic Institute of Hydrobiology Biology CentreCzech Academy of SciencesNa Sádkách 7CZ-37005(C)eskéBudějoviceCzech Republic

Forest practices in headwater catchments are related to environmental and social *** aim of this study is to analyse the changing protective functions of forests in the upper plain of the Jizera Mts.(North Bohemia,Czech Republic)since the second half of the 19th *** time,forests have gradually changed from native stands to spruce plantations(Picea abies),introducing exotic conifers(more resistant to air pollution),and,recently,back to more diverse mixed *** priority in pro-tective forest functions there shifted from flood protection to integrated control of water resources(quantity and quality).In the 1980s,forest-water interactions were degraded by consequences of extreme acid atmospheric deposition,forest die-back,and extensive *** the Jizerka catchment,first signs of recovery were observed in the early *** waters there are still affected by prolonged *** reconstruction of stream water chemistry at Jizerka follows the drop of the acid deposition in some 5 years,the revival of stream biota takes 10-15 *** 2071-2100,the pro-jected climate change shows rising annual air temperatures by 3.0-4.6℃,decreasing water yield by 65-123 mm,60%drop in'minimum residual discharge',and 20-30%rise in ***,these projected environmental changes cannot substantially decline the high potential in water resource recharge,or,start reverse processes in recent recovery from acidification and radically affect the exis-tence of planned mixed forests in the upper plain of the Jizera Mts.

关键词： Headwater catchment Forest functions Water resource recharge Acid atmospheric deposition Climate change

Celiac disease as potential obstacle to childbearing

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Open Journal of Obstetrics and Gynecology 2014年第2期4卷 75-80页

作者： Mónika kovács Mária Szenes Tihamér Horváth Gyorgy Vajda Beáta Gasztonyi Gyorgy Bártfai Department of Internal Medicine Zala County HospitalZalaegerszegHungary Department of Obstetrics and Gynecology Zala County HospitalZalaegerszegHungary Faculty of Medicine Obstetrics and Gynecology Department Albert Szent-Gyorgyi Clinical Center of University SzegedSzegedHungary

AIM: The authors have aimed at confirming or excluding gluten sensitivity in infertile couples. PATIENTS AND METHODS: Between 2004 and 2010, at our outpatient clinics of immunology, both partners of 223 couples, who had striven for having a child unsuccessfully, underwent history taking, physical examination, laboratory and immuno-serologic tests including anti-tissue-transglutaminase antibody (antitTG), as well as deep duodenal biopsy in antibody-carrying patients. RESULTS: Antibodies against tissue transglutaminase were positive in 6/223 female patients of whom the diagnosis of celiac disease was histologically confirmed in 3/223 cases (1.34%). Of the male patients 2/223 (0.9%) have proven to be carriers of the antibody;histology was pathognomonic in both of them. Curiously, one of the male patients with celiac disease has been the partner of a woman who also had celiac disease diagnosed by the authors. In the followup period, a female patient and the female member of the couple with celiac disease gave birth to healthy newborns after spontaneous conception, as the result of a strictly kept gluten-free diet, as well as occasional treatments of acetylsalicylate for antiphos-pholipid syndrome or levothyroxine for latent hypothyroidism due to autoimmune thyroiditis. CONCLUSION: The results underline that it is worth performing a screening for celiac disease in both partners of couples assessed due to the lack of success in having a child, as infertility can be ceased by an appropriate diet.

关键词： Celiac Disease Gluten-Free Diet Anti-Tissue-Transglutaminase Antibody Infertile Couples

Stability case study of the ACROBOTER underactuated service robot

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Theoretical & Applied Mechanics Letters 2012年第4期2卷 27-33页

作者： László L.kovács László Bencsik HAS-BME Research Group on Dynamics of Machines and Vehicles Budapest H-1521Hungary Department of Applied Mechanics Budapest University of Technology and EconomicsBudapest H-1521Hungary

The dynamics of classical robotic systems are usually described by ordinary differential equations via selecting a minimum set of independent generalized coordinates. However, different parameterizations and the use of a nonminimum set of （dependent） generalized coordinates can be advantageous in such cases when the modeled device contains closed kinematic loops and/or it has a complex structure. On one hand, the use of dependent coordinates, like natural coordinates, leads to a different mathematical representation where the equations of motion are given in the form of differential algebraic equations. On the other hand, the control design of underactuated robots usually relies on partial feedback linearization based techniques which are exclusively developed for systems modeled by independent coordinates. In this paper we propose a different control algorithm formulated by using dependent coordinates. The applied computed torque controller is realized via introducing actuator constraints that complement the kinematic constraints which are used to describe the dynamics of the investigated service robotic system in relatively simple and compact form. The proposed controller is applied to the computed torque control of the planar model of the ACROBOTER service robot. The stability analysis of the digitally controlled underactuated service robot is provided as a real parameter case study for selecting the optimal control gains.

关键词： stability underactuation natural coordinates control constraints

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

Antioxidant efficiency of lycopene on oxidative stress-induced damage in bovine spermatozoa

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Journal of Animal Science and Biotechnology 2017年第1期8卷 67-79页

作者： Eva Tvrdá Anton kovácik Eva Tusimová Dusan Paál Alica Mackovich Jakhongir Alimov Norbert Lukác Department of Animal Physiology Faculty of Biotechnology and Food Sciences Slovak University of Agriculture in Nitra Tr. A. Hlinku 2 Nitra 94976 Slovakia AgroBioTech Research Centre Slovak University of Agriculture in Nitra Tr. A. Hlinku 2 Nitra 94976 Slovakia Department of Botany and Genetics Faculty of Natural Sciences Constantine the Philosopher University in Nitra Nabbrezie mladeze 91 Nitra 94974 Slovakia Department of General Biology Faculty of Natural Sciences Gulistan State University 4th Microrayon Guliston 120100 Syrdarya Uzbekistan.

Background： Lycopene（LYC） is a natural carotenoid with powerful reactive oxygen species（ROS） scavenging activities. The aim of this study was to investigate if lycopene has the ability to reverse ROS-mediated alterations to the motility, viability and intracellular antioxidant profile of bovine spermatozoa subjected to ferrous ascorbate（Fe AA）. Spermatozoa were washed out of fresh bovine semen, suspended in 2.9 % sodium citrate and subjected to LYC treatment（0.25, 0.5, 1 or 2 mmol/L） in the presence or absence of Fe AA（150 μmol/L Fe SO4 and 750 μmol/L ascorbic acid） during a 6 h in vitro culture. Spermatozoa motion characteristics were assessed using the Sperm Vision？computer-aided sperm analysis（CASA） system. Cell viability was examined with the metabolic activity（MTT） assay,ROS generation was quantified via luminometry and the nitroblue-tetrazolium（NBT） test was applied to quantify the intracellular superoxide formation. Cell lysates were prepared at the end of the in vitro culture to investigate the intracellular activity of superoxide dismutase（SOD）, catalase（CAT）, glutathione peroxidase（GPx） as well as the concentrations of glutathione（GSH） and malondialdehyde（MDA）.Results： FeA A treatment led to a reduced spermatozoa motility（P 〈 0.001）, viability（P 〈 0.001） and a decline of the antioxidant capacity of spermatozoa（P 〈 0.001） but increased the ROS generation（P 〈 0.001）, superoxide production（P 〈 0.001） and lipid peroxidation（P 〈 0.001）. LYC administration resulted in a preservation of the spermatozoa motion parameters（P 〈 0.001）, mitochondrial activity（P 〈 0.001） and antioxidant characteristics（P 〈 0.001 with respect to SOD;P 〈 0.01 in relation to CAT; P 〈 0.05 as for GPx and GSH） with a concentration range of 1 and 2 mmol/L LYC revealed to be the most ***： Our results suggest that LYC exhibits significant ROS-scavenging and antioxidant properties which may prevent spermatozoa alterations caused by oxidative stress, and preserve the functional

关键词： Antioxidants Bulls Ferrous ascorbate Lycopene Oxidative stress Spermatozoa

Cavitation and grain boundary sliding during creep of Mg-Y-Nd-Zn-Mn alloy

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中国有色金属学会会刊：英文版 2008年第A1期18卷 64-68页

作者： V.JANíK F.HNILICA P.ZUNA V.OENEK I.STULíkov Department of Materials Engineering Faculty of Mechanical EngineeringCzech Technical University in PraguePragueCzech Republic Research Institute for Metals Panenské BrezanyCzech Republic Faculty of Mathematics and Physics Charles UniversityPragueCzech Republic

Creep of squeeze-cast Mg-3Y-2Nd-1Zn-1Mn alloy was investigated at the constant load in the stress range of 30-80 MPa. Tensile creep tests were performed at 300℃up to the final *** tests at 50 MPa were interrupted after reaching the steady state creep;and another set of creep tests was interrupted after the onset of ternary *** of cavitated dendritic boundaries was evaluated using optical *** of grain boundary sliding by observation of the offset of marker lines was carried out on the surface of the crept specimens after the test interruption by scanning electron microscopy and by confocal laser scanning *** results show that the dominant creep mechanism in this alloy is dislocation creep with minor contribution of the grain boundary *** failure took place by the nucleation,growth and coalescence of creep cavities on the boundaries predominantly oriented perpendicular to the applied *** amount of cavitated boundaries with time of creep exposure supports the mechanism of continuous cavity nucleation and growth.

关键词：镁合金锌合金锰合金高温测试