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Influence of AlTi3C0.15 modification treatment on damping properties of ZnAl10 alloy

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China Foundry 2017年第4期14卷 292-296页

作者： Grzegorz Piwowarski Janusz Buras michal Szucki Department of Foundry Processes Engineering Faculty of Foundry EngineeringAGH University of Science and TechnologyMickiewicza Al.3030-059 CraconePoland

Zn-Al alloys constitute an interesting group of foundry alloys. Due to a relatively low melting temperature, they allow a decrease in energy-consumption of the melting process and alloy preparation. The vibration damping ability is one of the most interesting properties of the Zn-Al alloys. Zn-Al alloys are divided into two groups: the low-aluminium and high-aluminium alloys. The investigated Zn-10 wt.% Al(ZnAl10) alloy is representative of the high-aluminium alloys, which, on account of its tendency of forming coarse-grained structures, has rather low plastic properties, including elongation. In order to improve the plastic properties, a modification treatment is usually applied. The dependence of the damping coefficient of the ultrasound wave on the amount of the introduced inoculant was studied. Investigations were performed using the AlT i3C0.15 inoculant as the modifier of the ZnAl10 alloy. It was found that titanium additions, in a range from 25 to 100 ppm in relation to the melted charge mass, can reduce the damping coefficient value. An increase of the inoculant addition causes a rise of the damping coefficient, which is probably related to the scattering of the ultrasound wave on Al_3Ti and TiC particles introduced with the inoculant.

关键词： modification damping damping coefficient zinc alloys ZnAl10 ultrasound wave

An Ensemble Methods for Medical Insurance Costs Prediction Task

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Computers, Materials & Continua 2022年第2期70卷 3969-3984页

作者： Nataliya Shakhovska Nataliia Melnykova Valentyna Chopiyak michal Gregus ml Department of Artificial Intelligence Lviv Polytechnic National UniversityLviv79013Ukraine Department of Clinical Immunology and Allergology Danylo Halytsky Lviv National Medical UniversityLviv79010Ukraine Faculty of Management Comenius UniversityBratislava81499Slovakia

The paper reports three new ensembles of supervised learning predictors for managing medical insurance *** open dataset is used for data analysis methods *** usage of artificial intelligence in the management of financial risks will facilitate economic wear time and money and protect patients’*** learning is associated withmany expectations,but its quality is determined by choosing a good algorithm and the proper steps to plan,develop,and implement the *** paper aims to develop three new ensembles for individual insurance costs prediction to provide high prediction *** coefficient and Boruta algorithm are used for feature *** boosting,stacking,and bagging ensembles are built.A comparison with existing machine learning algorithms is *** modes based on regression tree and stochastic gradient descent is *** CART and Random Forest algorithms are *** boosting and stacking ensembles shown better accuracy than *** tuning parameters for boosting do not allow to decrease the RMSE ***,bagging shows its weakness in generalizing the *** stacking is developed using K Nearest Neighbors(KNN),Support Vector Machine(SVM),Regression Tree,Linear Regression,Stochastic Gradient *** random forest(RF)algorithm is used to combine the *** hundred trees are built *** Square Error(RMSE)has lifted the to 3173.213 in comparison with other *** quality of the developed ensemble for RootMean Squared Error metric is 1.47 better than for the best weak predictor(SVR).

关键词： Healthcare medical insurance prediction task machine learning ensemble data analysis

Soil moisture content as a predictor of soil disturbance caused by wheeled forest harvesting machines on soils of the Western Carpathians

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Journal of Forestry Research 2017年第2期28卷 283-289页

作者： michal Allman Martin Jankovsk Valéria Messingerov Zuzana Allmanov Department of Forest Harvesting Logistics and AmeliorationsFaculty of ForestryTechnical University in ZvolenT.G.Masaryka 24960 53 ZvolenSlovakia

Limiting surface soil disturbance caused by forest harvesting machines is an important task and is influenced by the selection of efficient and reliable predictors of such disturbance. Our objective was to determine whether soil moisture content affects soil load bearing capacity and the formation of ruts. Measurements were conducted in six forest stands where various machines operated. We measured the formation of ruts along skid trails in connection with varying soil moisture content. Soil moisture content was determined through the gravimetric sampling method. Our results showed that severe（rut depth16–25 cm） to very severe disturbance（rut depth [26 cm）occurred in forest stands where the instantaneous soil moisture exceeded its plasticity limits defined through Atterberg limits. Atterberg limits of soil plasticity ranged from 26 to 32 % in individual stands. Regression and correlation analysis confirmed a moderately strong relationship（R = 0.52; p ／ 0.05） between soil moisture content and average rut depth. This confirmed that soil moisture is a suitable and effective predictor of soil disturbance.

关键词： disturbance moisture machines stands plasticity harvesting predictor moderately operated limits

Recent Progress in Emerging Two‑Dimensional Transition Metal Carbides

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Nano-Micro Letters 2021年第11期13卷 375-408页

作者： Tianchen Qin Zegao Wang Yuqing Wang Flemming Besenbacher michal Otyepka Mingdong Dong College of Materials Science and Engineering Sichuan UniversityChengdu 610065People’s Republic of China Interdisciplinary Nanoscience Center Aarhus University8000 AarhusDenmark Regional Centre of Advanced Technologies and Materials Department of Physical ChemistryFaculty of SciencePalacky University77146 OlomoucCzech Republic

As a new member in two-dimensional materials family,transition metal carbides(TMCs)have many excellent properties,such as chemical stability,in-plane anisotropy,high conductivity and flexibility,and remarkable energy conversation efficiency,which predispose them for promising applications as transparent electrode,flexible electronics,broadband photodetectors and battery ***,up to now,their device applications are in the early stage,especially because their controllable synthesis is still a great *** review systematically summarized the state-of-the-art research in this rapidly developing field with particular focus on structure,property,synthesis and applicability of ***,the current challenges and future perspectives are outlined for the application of 2D TMCs.

关键词： Two-dimensional transition metal carbides Phase diagram Superconductivity Energy conversation and storage Largescale synthesis

Factors shaping life history traits of two proovigenic parasitoids

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Integrative Zoology 2018年第3期13卷 297-306页

作者： michal SEGOLI Shucun SUN Dori ENAVA Jay A.ROSENHEIM Mitrani Department of Desert Ecology The Jacob Blaustein Institutes for Desert ResearchBen-Gurion University of the NegevMidreshet Ben-GurionIsrael Department of Ecology School of Life ScienceNanjing UniversityNanjingChina Embrapa Clima Temperado(Embrapa Temperate Agriculture) PelotasRio Grande do SulBrazil Department of Entomology and Nematology University of California DavisDavisCaliforniaUSA

What shapes the relative investment in reproduction versus survival of organisms is among the key questions in life *** insects mature all their eggs prior to emergence and are short lived,providing a unique opportunity to quantify their lifetime investments in the different *** investigated the initial eggloads and longevity of 2 proovigenic parasitoid wasps:Anagrus erythroneurae and Anagrus daanei,(Hymenoptera:Mymaridae)that develop within leafhopper eggs in both agricultural vineyards and natural riparian habitats in Northern *** collected Vitis *** containing developing parasitoids from 3 natural sites(Knight Landing,American River and Putah Creek)and 3 agricultural vineyards(Solano Farm,Davis Campus and Village Homes).We recorded eggloads at parasitoid emergence and female parasitoid longevity with or without *** predicts that parasitoids from vineyards(where hosts are abundant)would have higher initial eggloads and lower longevity compared with parasitoids from riparian habitats(where hosts are scarce).Although host density and parasitoid eggloads were,indeed,higher in vineyards than in riparian habitats,parasitoid longevity did not follow the predicted *** without feeding differed among field sites,but it was not affected by habitat type(natural vs agricultural),whereas longevity with feeding was not significantly affected by any of the examined ***,longevity was positively,rather than negatively,correlated with eggloads at the individual level,even after correcting for parasitoid body *** combined results suggest a more complex allocation mechanism than initially predicted,and the possibility of variation in host quality that is independent of size.

关键词： Anagrus parasitoids eggload leafhoppers life-history tradeoffs longevity

Laser ablation of hepatocellular carcinoma-A review

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World Journal of Gastroenterology 2008年第47期14卷 7170-7174页

作者： Antony Lawrence Gough-Palmer Wladyslaw michal Witold Gedroyc MRI Department St Mary's HospitalImperial Healthcare NHS trustPraed StLondon W2 1NYUnited Kingdom

A wide range of local thermal ablative therapies have been developed in the treatment of non resectable hepatocellular carcinoma(HCC) in the last *** ablation(LA) and radiofrequency ablation(RFA) are the two most widely used of *** article provides an up to date overview of the role of laser ablation in the local treatment of *** principles,technique,image guidance and patient selection are discussed.A review of published data on treatment efficacy,long term outcome and complication rates of laser ablation is included and comparison with RFA *** role of laser ablation in combination with transcatheter arterial chemoembolisation is also discussed.

关键词： Liver Carcinoma Hepatocellular Lasertherapy

Dolomite fracture modeling using the Johnson-Holmquist concrete material model:Parameter determination and validation

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第2期13卷 335-350页

作者： michal Kucewicz Pawel Baranowski Jerzy Maachowski Faculty of Mechanical Engineering Institute of Mechanics and Computational EngineeringMilitary University of Technology2 Gen.S.Kaliskiego StreetWarsaw00-908Poland

In this paper,the Johnson-Holmquist concrete(JHC)constitutive model is adopted for modeling and simulating the fracture of dolomite.A detailed step-by-step procedure for determining all required parameters,based on a series of experiments under quasi-static and dynamic regimes,is *** rate coefficients,failure surfaces,equations of state and damage/failure constants are acquired based on the experimental data and finite element *** JHC model with the obtained parameters for dolomite is subsequently validated using quasi-static uniaxial and triaxial compression tests as well as dynamic split Hopkinson pressure bar(SHPB)*** influence of mesh size is also *** shows that the simulated fracture behavior and waveform data are in good agreement with the experimental data for all tests under both quasi-static and dynamic loading *** studies will implement the validated JHC model in small-and large-scale blasting simulations.

关键词： Johnson-Holmquist concrete(JHC)model Rock modeling Dolomite Constitutive modeling Split Hopkinson pressure bar(SHPB) Fracture Triaxial compression

Novel insights into conjugation of antitumor-active unsymmetrical bisacridine C-2028 with glutathione:Characteristics of non-enzymatic and glutathione S-transferase-mediated reactions

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Journal of Pharmaceutical Analysis 2021年第6期11卷 791-798页

作者： Agnieszka Potega michal Kosno Zofia Mazerska Department of Pharmaceutical Technology and Biochemistry Faculty of ChemistryGda nsk University of TechnologyGdansk80-233Poland

Unsymmetrical bisacridines(UAs) are a novel potent class of antitumor-active therapeutics.A significant route of phase II drug metabolism is conjugation with glutathione(GSH),which can be non-enzymatic and/or catalyzed by GSH-dependent *** aim of this work was to investigate the GSHmediated metabolic pathway of a representative UA,***-supplemented incubations of C-2028 with rat,but not with human,liver cytosol led to the formation of a single GSH-related ***,it was also revealed with rat liver *** formation was NADPH-independent and was not inhibited by co-incubation with the cytochrome P450(CYP450) inhibitor ***,the direct conjugation pathway occurred without the prior CYP450-catalyzed bioactivation of the *** turn,incubations of C-2028 and GSH with human recombinant glutathione S-transferase(GST) P1-1 or with heat-/ethacrynic acid-inactivated liver cytosolic enzymes resulted in the presence or lack of GSH conjugated form,*** findings proved the necessary participation of GST in the initial activation of the GSH thiol group to enable a nucleophilic attack on the substrate *** C-2028-GSH S-conjugate was also formed during non-enzymatic *** GSH S-conjugates were characterized by combined liquid chromatography/tandem mass *** for their formation were *** ability of C-2028 to GST-mediated and/or direct GSH conjugation is suspected to be clinically *** may affect the patient’s drug clearance due to GST activity,loss of GSH,or the interactions with GSH-conjugated ***,GST-mediated depletion of cellular GSH may increase tumor cell exposure to reactive products of UA metabolic transformations.

关键词： Antitumor agent Unsymmetrical bisacridine Metabolic detoxification Glutathione S-Conjugate Glutathione S-transferase Non-enzymatic conjugation

PNN-SVM Approach of Ti-Based Powder’s Properties Evaluation for Biomedical Implants Production

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Computers, Materials & Continua 2022年第6期71卷 5933-5947页

作者： Ivan Izonin Roman Tkachenko michal Gregus Zoia Duriagina Nataliya Shakhovska Lviv Polytechnic National University Lviv79013Ukraine Comenius University in Bratislava Bratislava82005Slovak Republic The John Paul II Catholic University of Lublin Lublin20-708Poland

The advent of additive technologies has provided a significant breakthrough in the production of medical *** has reduced costs,increased productivity and accuracy of the implant manufacturing ***,there are problems associated with assessing defects in the microstructure,mechanical and technological properties of alloys,both during their production by powder metallurgy and in the process of 3D *** traditional research methods of alloys properties demand considerable human,material,and time *** the same time,artificial intelligence tools create opportunities for intelligent evaluation of the conformity for the microstructure,phase composition,and properties of titanium powder’s *** provides new possibilities for the efficient production of biocompatible implants for various functional ***,the accuracy of the methods and models used should be as high as *** this paper we designed a hybrid PNN-SVM(Probabilistic Neural Network-Support Vector Machine)high-precision approach for the intelligent evaluation of alloy properties for additive manufacturing of biomedical *** have proposed a new approach for extending the dimensionality of input data space by the outputs of the summation layer of the modified PNN *** classification based on the expanded dataset is performed using *** conducted experimental modeling of the proposed approach using a data set on the properties of titanium alloys Ti-6Al-4V and *** have demonstrated a significant increase in the accuracy of the PNN-SVM scheme compared to the single classifiers that form it and other machine learning methods.

关键词： PNN SVM hybrid systems classification accuracy medical implants additive manufacturing 3D printing titanium alloys