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Wave Radiation by a Floating Body in Water of Finite Depth Using an Exact DtN Boundary Condition

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Journal of Ocean University of China 2023年第6期22卷 1497-1504页

作者： rim Un-Ryong Institute of Ocean Engineering Kim Chaek University of TechnologyPyongyang 999093Democratic People’s Republic of Korea

The present paper focuses on the wave radiation by an oscillating body with six degrees of freedom by using the DtN artifi-cial boundary *** artificial boundary is usually selected as a circle or spherical surface to solve various types of fields,such as sound waves or electromagnetic waves,provided that the considered domain is infinite or unbounded in all ***,the substantial wave motion is considered in water of finite depth,that is,the fluid domain is bounded vertically but unbounded ***,the DtN boundary condition is given on an artificial cylindrical surface,which divides the water domain into an interior and exterior *** boundary integral equation is adopted to implement the present *** the case of a floating cylinder,the results of hydrodynamic coefficients of a chamfer box are discussed.

关键词： wave radiation boundary element method Dirichlet-to-Neumann map artificial boundary floating body finite-depth water

Plant growth and soil microbial community structure of legumes and grasses grown in monoculture or mixture

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Journal of Environmental Sciences 2008年第10期20卷 1231-1237页

作者： MARSCHNER petra Soil and Land System School of Earth and Environmental Sciences The University of AdelaideAdelaide 5005 Australia

A greenhouse pot experiment was conducted to investigate the in?uence of soil moisture content on plant growth and the rhizosphere microbial community structure of four plant species (white clover, alfalfa, sudan grass, tall fescue), grown individually or in a mixture. The soil moisture content was adjusted to 55% or 80% water holding capacity (WHC). The results indicated that the total plant biomass of one pot was lower at 55% WHC. At a given soil moisture, the total plant biomass of white clover and tall ...

关键词： legumes grasses the Chinese Loess Plateau microbial communities phospholipid fatty acid (PLFA)

Tooth wear against ceramic crowns in posterior region: a systematic literature review

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International Journal of Oral Science 2013年第4期5卷 183-190页

作者： rim Hmaidouch Paul Weigl Department of Prosthodontics and Geriatric Dentistry Johann Wolfgang Goethe University

The objective of this systematic review was to assess tooth wear against ceramic crowns in posterior region in vitro and in vivo. An electronic PubMed search was conducted to identify studies on tooth wear against ceramic crowns in posterior region. The selected studies were analyzed in regard to type of crowns, natural antagonist, measuring protocol and outcome. From a yield of 1 000 titles, 43 articles were selected for full-text analysis; finally, no in vitro and only five in vivo studies met the inclusion criteria. As there is heterogeneity in design, used measuring method, ceramics and analysis-form, a meta-analysis was not possible. Results of these studies are very controversial which makes a scientifically valid comparison impossible. This review indicated that some all-ceramic crowns are as wear friendly as metal-ceramic crowns. Up to now, it has been impossible to associate tooth wear with any specific causal agent. The role of ceramic surface treatment that might be responsible for the changing in rate of tooth wear seems undetermined as yet through clinical trials. The literature reveals that studies on this topic are subject to a substantial amount of bias. Therefore, additional clinical studies, properly designed to diminish bias, are warranted.

关键词： all-ceramic crowns tooth wear

Transition along gradient from warm to mesic temperate forests evaluated by GAMM

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Journal of Plant Ecology 2016年第4期9卷 421-433页

作者： AndražČarni Vlado Matevski Nina Juvan Mitko Kostadinovski petra Košir Aleksander Marinšek Andrej Paušič UrbanŠilc Institute of Biology Research Centre of the Slovenian Academy of Sciences and ArtsNovi trg 2SI-1000 LjubljanaSlovenia University of Nova Gorica Vipavska 13SI-5000 Nova GoricaSlovenia Macedonian Academy of Sciences and Arts Bul.Krste Misirkov2P.O.Box 428MK-1000 SkopjeRepublic of Macedonia Faculty of Natural Sciences and Mathematics Institute of BiologyUniversity of Ss.Cyril and MethodiusGazi Baba b/b-P.O.Box 162MK-1000 SkopjeRepublic of Macedonia Anton Melik Geographical Institute Research Centre of the Slovenian Academy of Sciences and ArtsNovi trg 2SI-1000 LjubljanaSlovenia Faculty of Mathematics Natural Sciences and Information TechnologiesUniversity of PrimorskaGlagoljaška 8SI-6000 KoperSlovenia Slovenian Forestry Institute Večna pot 2SI-LjubljanaSlovenia Kranjčeva 8 SI-9220 LendavaSlovenia Biotechnical Centre Naklo Strahinj 99SI-4202 NakloSlovenia

Aims The aim of the study was to discover what set of variables best explains the transition from warm to mesic forest *** on various variables grouped into sets(geomorphological,ecological,structural,soil characteristics and chorological),six models were built and tested by generalized additive mixed models(GAMMs).We assumed that each set of variables has different explanatory *** aim was to compare the six different models(sets of variables),to test which model best explains the species turnover in forest communities along the transition between warm and mesic temperate forests and to try to find reasons for the different explanatory power of the *** The research took place in the southern part of the Balkan *** sampling was done according to standard *** gradient from warm to mesic forests was defined as the turnover of species and evaluated by projection of samples on the first unconstrained DCA ***,ecological,structural and soil characteristics,together with chorological sets of variables,were regressed on the turnover of species *** on the five sets of variables,six models were constructed and tested by generalized additive mixed *** Findings Ecological conditions best explain the change of forest communities along the gradient;evolution and the development of vegetation reflected in chorotypes are also of high importance;geomorphology and structure seem not to change so dramatically and soil shows the least significant differences of *** variables are the most important set of variables in the transition between warm and mesic temperate forests but eco-evolutionary dynamics after the Pleistocene should also be taken into consideration.

关键词： Balkan chorotypes life forms ecology plant ecology soil science vegetation evolution refugium

Harnessing machine learning tools for water quality assessment in the Kebili shallow aquifers,Southwestern Tunisia

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Acta Geochimica 2024年第6期43卷 1065-1086页

作者： Zohra Kraiem Kamel Zouari rim Trabelsi Laboratory of Radio-Analyses and Environment National Engineering SchoolUniversity of Sfax11733038 SfaxTunisia

An integrated method that implements multivariate statistical analysis and ML methods to evaluate groundwater quality of the shallow aquifers of the Djerid and Kebili district,Southern Tunisia,was *** evaluation of their suitability for irrigation and/or drinking purposes is necessary.A comprehensive hydrochemical assessment of 52 samples with entropy weighted water quality index(EWQI)was also *** water parameters were calculated to ascertain the potential use of those resources in irrigation and *** analysis showed two main components with Dim1(variance=62.3%)and Dim.2(variance=22%),due to the bicarbonate,dissolution,and evaporation and the intrusion of drainage *** evaluation of water quality has been carried out using EWQI *** calculated EWQI for the Djerid and Kebili waters(i.e.,52 samples)varied between 7.5 and 152.62,indicating a range of 145.12.A mean of 79.12 was lower than the median(88.47).From the calculation of EWQI,only 14 samples are not suitable for irrigation because of their poor to extremely poor quality(26.92%).The bivariate plot showed high correlation for EWQI~TH(r=0.93),EWQI~SAR(r=0.87),indicating that water quality depended on those *** erent ML algorithms were successfully applied for the water quality classifi *** results indicated high prediction accuracy(SVM>LDA>ANN>kNN)and perfect classifi cation for kNN,LDA and Naive *** the purposes of developing the prediction models,the dataset was divided into two groups:training(80%)and testing(20%).To evaluate the models’performance,RMSE,MSE,MAE and R^(2) metrics were ***(R^(2)=0.9359,MAE=6.49,MSE=79.00)and LDA(accuracy=97.56%;kappa=96.21%)achieved high ***,linear regression indicated high correlation for both training(R^(2)=0.9727)and testing data(0.9890).This well confi rmed the validity of LDA algorithm in predicting water *** validation showed a high accuracy(92.31%),high sensitivity(89.47%)an

关键词： Water-resources management Multivariate analysis Machine learning Kebili and Djerid shallow aquifers EWQI Water classification

Homogenization on solution treatment and its effects on the precipitation-hardening of selective laser melted 17-4PH stainless steel

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Journal of Materials Science & Technology 2023年第35期166卷 47-57页

作者： Sohee An Du-rim Eo Il Sohn Kyunsuk Choi Department of Materials Science and Engineering Yonsei UniversitySeoul03722Republic of Korea Advanced Joining&Additive Manufacturing R&D Department Korea Institute of Industrial Technology(KITECH)529 Seohaean-roSiheung 15014Republic of Korea Department of Industry-University Convergence Hanbat National UniversityYuseongDaejeon34158Republic of Korea

17-4 precipitation-hardened(PH)stainless steel(SS)exhibits high strength and good corrosion resistance via Cu-precipitation *** conventional wrought 17-4PH SS,Cu segregation andε-Cu pre-cipitates are observed in additively manufactured(AM)17-4PH SS owing to the repeated rapid cooling after heating,which characterizes the AM *** this study,solution treatment was conducted under various temperatures(1,000,1,050,1,100,and 1,200℃)and durations(1,2,4,and 8 h)to minimize the negative effects of Cu segregation andε-Cu precipitates on precipitation *** mechanical prop-erties and microstructures of each condition for the Cu precipitation behavior were *** theε-Cu precipitates did not disappear after solution treatment,the average diameter of theε-Cu precipi-tates tended to decrease with increasing solution treatment temperature and ***,solution treatment at a temperature of 1,200℃ for 8 h was the best,resulting in improved strength compared to the conventional solution treatment at 1,050℃.Solution treatment on at least 1,100℃ is effective in AM.

关键词： Selective laser melting Cu segregation Solution treatment 17-4 Precipitation-hardened stainless steel Additive manufacturing

Challenges of deciphering gastric cancer heterogeneity

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World Journal of Gastroenterology 2015年第37期21卷 10510-10527页

作者： petra Hudler Institute of Biochemistry Faculty of MedicineUniversity of Ljubljana

Gastric cancer is in decline in most developed countries;however, it still accounts for a notable fraction of global mortality and morbidity related to cancer. Highthroughput methods are rapidly changing our view and understanding of the molecular basis of gastric carcinogenesis. Today, it is widely accepted that the molecular complexity and heterogeneity, both interand intra-tumour, of gastric adenocarcinomas presentsignificant obstacles in elucidating specific biomarkers for early detection of the disease. Although genomewide sequencing and gene expression studies have revealed the intricate nature of the molecular changes that occur in tumour landscapes, the collected data and results are complex and sometimes *** aberrant molecules have already been tested in clinical trials, although their diagnostic and prognostic utilities have not been confirmed thus far. The gold standard for the detection of sporadic gastric cancer is still the gastric endoscopy, which is considered invasive. In addition, genome-wide association studies have confirmed that genetic variations are important contributors to increased cancer risk and could participate in the initiation of malignant *** hypothesis could in part explain the late onset of sporadic gastric cancers. The elaborate interplay of polymorphic low penetrance genes and lifestyle and environmental risk factors requires additional research to decipher their relative impacts on *** purpose of this article is to present details of the molecular heterogeneity of sporadic gastric cancers at the DNA, RNA, and proteome levels and to discuss issues relevant to the translation of basic research data to clinically valuable tools. The focus of this work is the identification of relevant molecular changes that could be detected non-invasively.

关键词： Adenocarcinoma Biological markers Proteomics Molec

Introducing a New Tool for Studying Unstable Systems

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International Journal of Automation and computing 2014年第6期11卷 580-587页

作者： Frantiek Gazdo Tomas Bata University in Zlín Faculty of Applied Informatics nam.T.G.Masaryka 5555760 01 Zlin Czech Republic

This paper presents the starting project of a web site focussed on unstable systems. It is a web-based database in a bilingual version(English/Czech), which can be used as an information database for models of unstable processes. The web site contains the mathematical models of such systems, including their simulation files together with basic information about the stability of dynamic systems. The paper outlines the motivation for the development of this database, presents its basic structure, and discusses several models from the site. The areas of prospective usage are also suggested together with the possible directions of further development of this project. The contribution ends with a case study using the database for control system analysis and design of the Amira inverted pendulum. The systematic polynomial approach is fruitfully utilised for the task together with some useful tools from the robust control theory.

关键词： Unstable systems stability modelling simulation database robust control polynomial approach

EXPLICIT ERROR ESTIMATES FOR COURANT, CROUZEIX-RAVIART AND RAVIART-THOMAS FINITE ELEMENT METHODS

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Journal of Computational Mathematics 2012年第4期30卷 337-353页

作者： Carsten Carstensen Joscha Gedicke Donsub rim Institut fur Mathematik Humboldt-Universitiit zu Berlin Unter den Linden 6 10099 Berlin Germany Department of Computational Science and Engineering Yonsei University 120-749 Seoul Korea Institut fur Mathematik Humboldt-Universitat zu Berlin Unter den Linden 6 10099 Berlin Germany Yonsei School of Business and Department of Computational Science and Engineering Yonsei University 120-749 Seoul Korea

The elementary analysis of this paper presents explicit expressions of the constants in the a priori error estimates for the lowest-order Courant, Crouzeix-Raviart nonconforming and P^viart-Thomas mixed finite element methods in the Poisson model problem. The three constants and their dependences on some maximal angle in the triangulation are indeed all comparable and allow accurate a priori error control.

关键词： Error estimates Conforming Nonconforming Mixed Finite element method.