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Nonlocal-Means Image Denoising Technique Using Robust M-Estimator

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j.urnal of Computer Science & Technology 2010年第3期25卷 623-631页

作者： Dinesh j. Peter v. K. Gov.ndan Abraham T. Mathew Department of Computer Science National Institute of Technology Calicut Department of Electrical Engineering National Institute of Technology Calicut

Edge preserv.d smoothing techniques hav. gained importance for the purpose of image processing applications A good edge preserv.ng filter is giv.n by nonlocal-means filter rather than any other linear model based approaches. This paper explores a different approach of nonlocal-means filter by using robust M-estimator function rather than the exponential function for its weight calculation. Here the filter output at each pixel is the weighted av.rage of pixels with surrounding neighborhoods using the chosen robust M-estimator function. The main direction of this paper is to identify the best robust M-estimator function for nonlocal-means denoising algorithm. In order to speed up the computation, a new patch classification method is followed to eliminate the uncorrelated patches from the weighted av.raging process. This patch classification approach compares fav.rably to existing techniques in respect of quality v.rsus computational time. v.lidations using standard test images and brain atlas images hav. been analyzed and the results were compared with the other known methods. It is seen that there is reason to believ. that the proposed refined technique has some notable points.

关键词： image processing denoising technique nonlocal-means filter robust M-estimators

HDPairFinder:A data processing platform for hydrogen/deuterium isotopic labeling-based nontargeted analysis of trace-lev.l amino-containing chemicals in env.ronmental water

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j.urnal of Env.ronmental Sciences 2024年第2期136卷 583-593页

作者： Tingting Zhao Kristin Carroll Caley B.Crav.n Nicholas j.P.Wawryk Shipei Xing j.an Guo Xing-Fang Li Tao Huan Department of Chemistry Faculty of ScienceUniversity of British ColumbiaVancouver Campus2036 Main MallVancouverBritish ColumbiaV6T 1Z1Canada Div.sion of Analytical and Env.ronmental Toxicology Department of Laboratory Medicine and PathologyFaculty of Medicine and DentistryUniversity of AlbertaEdmontonAlberta T6G 2G3Canada

The combination of hydrogen/deuterium(H/D)formaldehyde-based isotopic methyl labeling with solid-phase extraction and high-performance liquid chromatography–high resolution mass spectrometry(HPLC-HRMS)is a powerful analytical solution for nontargeted analysis of trace-lev.l amino-containing chemicals in water *** the huge amount of chemical information generated in HPLC-HRMS analysis,identifying all possible H/Dlabeled amino chemicals presents a significant challenge in data *** address this,we designed a streamlined data processing pipeline that can automatically extract H/D-labeled amino chemicals from the raw HPLC-HRMS data with high accuracy and ***,we dev.loped a cross-correlation algorithm to correct the retention time shift resulting from deuterium isotopic effects,which enables reliable pairing of H-and D-labeled ***,we implemented sev.ral bioinformatic solutions to remov. false chemical features generated by in-source fragmentation,salt adduction,and natural13C ***,we used a data mining strategy to construct the AMINES library that consists of ov.r 38,000 structure-disj.inted primary and secondary amines to facilitate putativ. compound ***,we integrated these modules into a freely av.ilable R program,*** rationale of each module was j.stified and its performance tested using experimental H/D-labeled chemical standards and authentic water *** further demonstrated the application of HDPairFinder to effectiv.ly extract N-containing contaminants,thus enabling the monitoring of changes of primary and secondary N-compounds in authentic water *** is a reliable bioinformatic tool for rapid processing of H/D isotopic methyl labeling-based nontargeted analysis of water samples,and will facilitate a better understanding of N-containing chemical compounds in water.

关键词： Isotope labeling Nontargeted analysis Reactiv. N-compounds HPLC-HRMS Source water

Study of engine performance, emission and combustion characteristics fueled with diesel-like fuel produced from waste engine oil and waste plastics

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Frontiers of Env.ronmental Science & Engineering 2018年第4期12卷 77-85页

作者： v. Edwin Geo Ankit Sonthalia Fethi AIoui Femilda j.sephin j. S. Department of Automobile Engineering SRM Institute of Science and Technology Kattankulathur-603203 India Department of Mechanical and Automobile Engineering SRM Institute of Science and Technology NCR Campus~ Modinagar-201204 India Campus Mont Houy F-5931 LAMIH UMR CNRS 8201 Department of Mechanical Engineering University of Valenciennes (UVHC) Campus Mont-Houy F-59313 Valenciennes Cedex 9 France Department of Software Engineering SRM Institute of Science and Technology Kattankulathur-603203 India

Utilizing oil extracted from waste engine oil and waste plastics, by pyrolysis, as a filel for internal combustion engines has been demonstrated to be one of the best av.ilable waste management methods. Separate blends of fuel from waste engine oil and waste plastic oil was prepared by mixing with diesel and experimental inv.stigation is conducted to study engine performance, combustion and exhaust emissions. It is observ.d that carbon monoxide （CO） emission increases by 50% for 50% waste plastic oil （50WPO：50D） and by 58% for 50% waste engine oil （50WEO：50D） at full load as compared to diesel. Unburnt hydrocarbon （HC） emission increases by 16% for 50WPO：50D and by 32% for 50WEO：50D as compared to diesel at maximum load. Smoke is fotmd to decrease at all loading conditions for 50WPO：50D operation, but it is comparativ.ly higher for 50WEO：50D operation. 50WPO：50D operation shows higher brake thermal efficiency for all loads as compared to 50WEO：50D and diesel fuel operation. Exhaust gas temperature is higher at all loads tbr 50WPO：50D and 50WEO：50D as compared to diesel fuel operation.

关键词： Waste engine Oil Waste plasti Oil Diesel fuelPyrolysis Compression engine

Periodicities in Solar Activ.ty, Solar Radiation and Their Links with Terrestrial Env.ronment

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Natural Science 2023年第3期15卷 111-147页

作者： v.lentina v. Zharkov. Irina v.siliev. Simon j. Shepherd Elena Popov. Department of MPEE University of Northumbria Newcastle upon Tyne UK Zv. Research Enterprise Ltd. London UK Department of Solar Physics Main Astronomical Observatory Kyiv Ukraine PRIMAL Research Group Sorbonne Universite Paris France Centro de Inv.stigación en Astronomía Universidad Bernardo O’Higgins Santiago Chile

Solar magnetic activ.ty is expressed v.a v.riations of sunspots and activ. regions v.rying on different timescales. The most accepted is an 11-year period supposedly induced by the electromagnetic solar dynamo mechanism. There are also some shorter or longer timescales detected: the biennial cycle (2 - 2.7 years), Gleisberg cycle (80 - 100 years), and Hallstatt’s cycle (2100 - 2300 years). Recently, using Principal Component Analysis (PCA) of the observ.d solar background magnetic field (SBMF), another period of 330 - 380 years, or Grand Solar Cycle (GSC), was deriv.d from the summary curv. of two eigenv.ctors of SBMF. In this paper, a spectral analysis of the av.raged sunspot numbers, solar irradiance, and the summary curv. of eigenv.ctors of SBMF was carried out using Morlet wav.let and Fourier transforms. We detect a 10.7-year cycle from the sunspots and modulus summary curv. of eigenv.ctors as well a 22-year-cycle and the grand solar cycle of 342 - 350-years from the summary curv. of eigenv.ctors. The Gleissberg centennial cycle is only detected on the full set of av.raged sunspot numbers for 400 years or by adding a quadruple component to the summary curv. of eigenv.ctors. Another period of 2200 - 2300 years is detected in the Holocene data of solar irradiance measured from the abundance of 14C isotope. This period was also confirmed with the period of about 2000 - 2100 years deriv.d from a baseline of the solar background magnetic field, supposedly, caused by the solar inertial motion (SIM) induced by the grav.tation of large planets. The implication of these findings for different deposition of solar radiation into the northern and southern hemispheres of the Earth caused by the combined effects of the solar activ.ty and solar inertial motion on the terrestrial atmosphere is also discussed.

关键词： Sun: Magnetic Field Sun: Solar Activ.ty Sun: Sunspots Sun: Solar Dynamo

Bulking Up the Bay-Position Substituents Enables Enhanced Selectiv.ty of C_(s)‑Symmetric Boron Subphthalocyanine−Subnaphthalocyanine Hybrids

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Precision Chemistry 2024年第4期2卷 161-181页

作者： Nina F.Farac Alan j.Lough Timothy P.Bender Department of Chemical Engineering and Applied Chemistry University of TorontoTorontoOntario M5S 3E5Canada Department of Chemistry University of TorontoTorontoOntario M5S 3H6Canada Department of Materials Science and Engineering University of TorontoTorontoOntario M5S 3E4Canada Department of Mechanical and Industrial Engineering University of TorontoTorontoOntario M5S 3G8Canada

The precise synthesis of subporphyrinoid hybrids withπ-expanded topologies and unique material properties plays a promising role in the design of functional ***,selectiv.,and controllable routes to boron subphthalocyanine−subnaphthalocyanine hybrids,Bsub(Pc_(3‑p)-Nc_(p))s,are desirable for this purpose yet synthetically challenging due to random mixtures of C_(s-),C_(3v.),and,in some cases,C_(1)-symmetric compounds that form during traditional statistical mixed ***,we addressed this issue by dev.loping a sterically driv.n mixed cyclotrimerization with enhanced selectiv.ty for the targeted C_(s)-symmetric hybrid and complete suppression of sterically crowded macrocyclic *** process,coupled with a rationally designed precursor bearing bulky phenyl substituents,enabled the synthesis and characterization of bay-position phenylated Ph_(2)-(R_(p))_(8)Bsub(Pc_(2)-Nc_(1))hybrids with halogens(Rp=Cl or F)in their peripheral isoindole *** selectiv.ty ranged between 59 and 72%with remarkable yields,significantly higher than that of conv.ntional mixed *** findings were augmented by theoretical calculations on precursor Lewis basicity as guiding principles into hybrid macrocycle ***,the incorporation of unfused phenyl groups and halogen atoms into the hybrid framework resulted in fine-tuned optical,structural,electronic,and electrochemical *** straightforward approach achiev.d improv.d selectiv.ty and controlled narrowing of the product distribution,affording the efficient synthesis of structurally sophisticated Bsub(Pc_(2)-Nc_(1))*** then expands the library of 3-dimensionalπ-extended macrocycles for use in a range of applications,such as in optoelectronic dev.ces with precisely tailored optical properties.

关键词： subphthalocyanine hybrids low-symmetry aromatic macrocycle selectiv. cyclotrimerization sterically driv.n chemistry broad absorption material properties

In v.v. and in v.tro study of resorbable magnesium wires for medical implants:Mg purity,surface quality,Zn alloying and polymer coating

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j.urnal of Magnesium and Alloys 2024年第6期12卷 2472-2488页

作者： K.Tesar j.Luňáckov. M.j.x M.Žaloudkov. R.v.bov. M.Bartoš P.Klein L.v.štej.ov. j.Duškov. E.Filov. Z.Sucharda M.Steinerov. S.Habr K.Balík A.Singh Department of Materials Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueTrojanova 13Prague 12000Czech Republic Institute of Physics Czech Academy of SciencesNa Slovance 2Prague 18221Czech Republic Institute of Dental Medicine First Faculty of MedicineCharles University and General University Hospital in PragueKaterinská32Prague 12801Czech Republic Department of Physics Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueBrehová7Prague 11519Czech Republic Department of Composites and Carbon Materials Institute of Rock Structure and MechanicsCzech Academy of SciencesV Holešovickách 41Prague 18209Czech Republic Institute of Anatomy First Faculty of MedicineCharles UniversityU Nemocnice 3Prague 12800Czech Republic Biomedical Center Faculty of Medicine in PilsenCharles UniversityAlej Svobody 76Pilsen 32300Czech Republic Department of Pathological Physiology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic Department of Histology and Embryology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic Institute of Pathology First Faculty of MedicineCharles University and General University Hospital in PragueStudnickova 2Prague 12800Czech Republic Department of Biomaterials and Tissue Engineering Institute of PhysiologyCzech Academy of SciencesVidenska 1083Prague 14200Czech Republic Research Center for Structural Materials National Institute for Materials Science1-2-1 SengenTsukuba 305-0047Japan

Magnesium is an excellent material in terms of biocompatibility and its corrosion products can serv. as an activ. source for new bone ***,localized corrosion and H_(2)generation limit the potential of Mg-based *** low-alloyed Mg-Zn wires can strongly reduce problems with large H_(2)bubbles and improv. the mechanical properties considerably while maintaining excellent long-term *** pickling and a polymer coating can be effectiv.ly used to lower the rate of in v.v. *** this work,microstructural,mechanical,and in v.tro characterization of 250μm and 300μm extruded wires made from ultra-pure Mg,commercially pure Mg,Mg-0.15Zn,Mg-0.4Zn and Mg-1Zn was ***,Mg-0.4Zn wires together with a v.riant coated with a copolymer of L-lactide andε-caprolactone were tested in v.v. on artificially damaged Wistar rat *** on the observ.d Mg-induced osteogenesis,polymer-coated Mg wires with a small addition of Zn are a perspectiv. material for bone-support applications,such as cerclage and fixation wires.

关键词： Magnesium Resorbable Mg wire Mg-Zn implant degradation Biocompatibility study Zn grain boundary segregation

Resolution Enhancement of Optical Surface Plasmon Resonance Sensor Using Metamaterial

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Photonic Sensors 2015年第4期5卷 330-338页

作者： Sarika PAL Y. K. PRAj.PATI j. P. SAINI v. SINGH Sarika Pal Department of Electronics & Communication Engineering KIET Ghaziabad (U.P.) India yogendra Kumar Praj.pati Department of Electronics & Communication Engineering MNNIT Allahabad-211004 (U.P.) India j.i Prakash Saini Department of Electronics & Communication Engineering BIET Jhansi-284128 (U.P.) India v.v.k Singh Department of Physics Faculty of Science Banaras Hindu University Varanasi (U.P.) India

In this paper, we present and discuss a an optical surface plasmon resonance （SPR） path to extend the enhancement of the resolution of sensor. Basically, our approach is to combine bi-metamaterial layers to design the SPR sensor. The calculation shows that the proposed SPR sensor structure has a preference ov.r the conv.ntional SPR sensors and bimetallic SPR sensors since it giv.s a much sharper reflectance dip and can achiev. considerable sensitiv.ty improv.ment when compared to the recently reported inv.stigations. The effects of the metamaterial permittiv.ty, permeability, and thickness on the reflectance curv. are studied. It is also seen that metamaterial layers improv. the field of the proposed SPR structure, which may prov.de a nov.l tool to significantly enhance the sensitiv.ty and resolution of the sensors.

关键词： Surface plasmon resonance sensor metamaterials Fresnel equations reflectance

Quantifying golf course nitrogen use efficiency

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Grassland Research 2022年第3期1卷 174-186页

作者： Michael A.H.Bekken douglas j.Soldat Department of Soil Science University of Wisconsin-MadisonMadisonWisconsinUSA

Background:Prev.ous studies hav. surv.yed golf courses to determine nitrogen(N)fertilizer application rates on golf courses,but no prev.ous studies hav. attempted to quantify how efficiently golf courses use ***:This study tests the ability of the growth potential(GP)N Requirement model as a benchmarking tool to predict a target lev.l of N use on 76 golf courses in 5 regions of the US(Midwest,Northeast,East Texas,Florida,Northwest)and 3 countries in Europe(Denmark,Norway,UK).Results:The ratio of the golf course-wide N application rate to the GP N requirement prediction(termed the nitrogen efficiency score or NES)was 0.27,indicating that golf courses used 73%less N than predicted by the *** such,the GP N Requirement model needs to be recalibrated to predict N use on golf *** was achiev.d by adj.sting the Nmax coefficient in the model.N rates on golf courses were widely v.riable both within and across *** regions had a coefficient of v.riation in N rates of 0.46 or ***:The high v.riation in N rates,which is largely unexplained by climate,economic factors,grass type,and soil type,may be indicativ. of inefficient N use in golf course management.

关键词： biophysical modeling decision support tools fertilizer golf growth potential nitrogen nitrogen efficiency turfgrass

Photonuclear reactions on stable isotopes of selenium at bremsstrahlung end-point energies of 10-23 Mev

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Chinese Physics C 2024年第2期48卷 91-103页

作者： F.A.Rasulov. N.v.Aksenov.S.I.Alekseev.R.A.Aliev.S.S.Belyshev.I.Chuprakov.N.Yu.Fursov. A.S.Madumarov.j.H.Khushv.ktov.A.A.Kuznetsov.B.S.Yuldashev j.int Institute for Nuclear Research DubnaRussia Institute of Nuclear Physics of the Academy of Sciences of the Republic of Uzbekistan TashkentUzbekistan Faculty of Chemistry of Lomonosov.Moscow State Univ.rsity MoscowRussia National Research Center"Kurchatov.Institute" MoscowRussia Skobeltsyn Institute of Nuclear Physics of Lomonosov.Moscow State Univ.rsity MoscowRussia Faculty of Physics of Lomonosov.Moscow State Univ.rsity MoscowRussia Institute of Nuclear Physics AlmatyRepublic of Kazakhstan

In this study,experiments were performed at bremsstrahlung end-point energies of 10-23 Mev.with the beam from the MT-25 microtron using theγ-activ.tion *** experimental v.lues of relativ. yields were compared with theoretical results obtained on the basis of TALYS with the standard parameters and the combined model of photonucleon *** isospin splitting in the combined model of photonucleon reactions allows describing experimental data on reactions with proton escape in the energy range from 10 to 23 ***,taking into account isospin splitting is necessary for a correct description of the decay of the giant dipole resonance.

关键词： bremsstrahlung photon cross section isospin splitting giant dipole resonance