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A project-Based Sustainability Rating Tool for pavement Maintenance

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Engineering 2018年第2期4卷 36-44页

作者： Yibo Zhang J.p. Mohsen Department of Civil and Environmental Engineering University of Louisville Louisville KY 40208 USA

pavements require maintenance to prevent undue distress or to restore performance; however, pavement maintenance and its impacts do not receive enough attention in many cases, and are either ignored or treated as a low priority, Most current maintenance activities have budget issues and only focus on removing deteriorated pavement sections, Deferred pavement maintenance has impacts on the environment and on society, and may thus affect the costs associated with maintenance, A sustain- ability rating tool is a good way to list, explain, and evaluate such impacts, Various sustainahility rating tools have been developed for pavement; however, pavement maintenance has its own features that are different from those of the new construction, expansion, or reconstruction of pavements, This research project reviews nine sustainahility rating tools for pavement, although none of these tools fully describe maintenance features or can he directly applied to evaluate maintenance projects, A new sustainahility rating tool is then developed for pavement maintenance; this new tool can he used to evaluate individual projects and raise public awareness about the importance of pavement mainte- nance, Its details are described, and its use is demonstrated through an example to show the evaluation process and results,

关键词： Sustainability pavement maintenance pSIMRating tool Analytic hierarchy process

Engineered quasi-phase-matching for laser techniques[Invited]

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photonics Research 2013年第4期1卷 171-185页

作者： X.p.Hu p.Xu S.N.Zhu National Laboratory of Solid State Microstructures and School of physics Nanjing UniversityNanjing 210093China

The quasi-phase-matching(QpM)technique has drawn increasing attention due to its promising applications in areas such as nonlinear frequency conversion for generating new laser light *** this paper,we will briefly review the main achievements in this *** give a brief introduction of the invention of QpM theory,followed by the QpM-material fabrication *** combing QpM with the solid-state laser techniques,various laser light sources,such as single-wavelength visible lasers and ultraviolet lasers,red–green–blue three-fundamentalcolor lasers,optical parametric oscillators in different temporal scales,and passive mode-locking lasers based on cascaded second-order nonlinearity,have been *** QpM technique has been extended to quantum optics recently,and prospects for the studies are bright.

关键词： Engine matching phase

Management of non-variceal upper gastrointestinal tract hemorrhage:Controversies and areas of uncertainty

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World Journal of Gastroenterology 2012年第11期18卷 1159-1165页

作者： Eric p Trawick patrick S Yachimski Division of Gastroenterology Hepatology and NutritionVanderbilt University Medical Center

Upper gastrointestinal tract hemorrhage （UGIH） remains a common presentation requiring urgent evaluation and treatment. Accurate assessment, appropriate intervention and apt clinical skills are needed for proper management from time of presentation to discharge. The advent of pharmacologic acid suppression, endoscopic hemostatic techniques, and recognition of Helicobacter pylori as an etiologic agent in peptic ulcer disease （pUD） has revolutionized the treatment of UGIH. Despite this, acute UGIH still carries considerable rates of morbidity and mortality. This review aims to discuss current areas of uncertainty and controversy in the management of UGIH. Neoadjuvant proton pump inhibitor （ppI） therapy has become standard empiric treatment for UGIH given that pUD is the leading cause of non variceal UGIH, and ppIs are extremely effective at promoting ulcer healing. Howeve, neoadjuvant ppI administration has not been shown to affect hard clinical outcomes such as rebleeding or mortality. The optimal timing of upper endoscopy in UGIH is often debated. Upon completion of volume resuscitation and hemodynamic stabilization, upper endoscopy should be performed within 24 h in all patientswith evidence of UGIH for both diagnostic and therapeutic purposes. With rising healthcare cost paramount in today＇s medical landscape, the ability to appropriately triage UGIH patients is of increasing value. Upper en- doscopy in conjunction with the clinical scenario allows for accurate decision making concerning early discharge home in low risk lesions or admission for further moni toring and treatment in higher risk lesions. Concomitant pharmacotherapy with non steroidal antiinflammatory drugs （NSAIDs） and antiplatelet agents, such as clopidogrel, has a major impact on the etiology, severib/, and potential treatment of UGIH. Long term ppI use in patients taking chronic NSAIDs or clopidogrel is discussed thoroughly in this review.

关键词： Hemorrhage proton pump inhibitors He/i-cobacter py/ori prokinetic agents Hemostasis Thieno-pyridines

COVID-19 in Brazil:Epidemiological update and perspectives

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Asian pacific Journal of Tropical Medicine 2020年第5期13卷 193-196页

作者： Marli C Cupertino Graziela A Cupertino Andréia p Gomes Nicholas AJ Mayers R Siqueira-Batista Medical School Faculdade Dinamica do Vale do PirangaPonte NovaMinas GeraisBrazil Laboratory of Epidemiological and Computational Methods in Health Department of Medicine and NursingUniversidade Federal de VicosaVicosaMinas GeraisBrazil Department of Veterinary Medicine Universidade Federal de VicosaVicosaMinas GeraisBrazil

Coronaviruses are RNA viruses (Family: Coronaviridae) constituents of a significant number of viruses that provoke diseases in animals and human beings. There are four genera of these microorganisms: Alphacoronavirus, Betacoronavirus, Deltacoronavirus and Gammacoronavirus. From this group, the alpha- and beta-coronaviruses are designated as human coronavirus (HCoV) for their propensity to infect human beings[1].

关键词： diseases Corona Brazil

The CASTOR-K Code,Recent Developments and Applications

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plasma Science and Technology 2015年第2期17卷 89-96页

作者： F.NABAIS D.BORBA R.COELHO A.FIGUEIREDO J.FERREIRA N.LOUREIRO p.RODRIGUES Associao EURATOM/IST Instituto de Plasmas e Fuso Nuclear-Instituto Superior TcnicoUniversidade de Lisboa

The CASTOR-K code is a hybrid magnetohydrodynamic （MHD）-drift kinetic code developed for the study of MHD modes in the presence of energetic ion populations. It allows a fast assessment of the linear stability of the modes, as well as an accurate calculation of damping due to thermal species （Landau damping）. These capabilities make the code an invaluable tool for parametric studies and data analysis. In recent years, CASTOR-K has been mostly used to analyze JET data, including the identification of mechanisms involved in the expulsion of energetic ions from the plasma. However, in order to prepare the code to be used for a wider range of tokamaks including ITER, the code is being subject to a series of important improvements. These improvements aim not only to introduce new physics in the code but also to make it capable of exchanging data with other codes through its integration in modelling infrastructures. In this paper a description of the CASTOR-K code is presented, as well as a summary of the most important results obtained with this code and a description of the new improvements being implemented.

关键词： controlled fusion tokamaks plasma instabilities magnetohydrodynamics(MHD) Alfven waves energetic particles

SUBSpACE SEARCH METHOD FOR A CLASS OF LEAST SQUARES pROBLEM

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Journal of Computational Mathematics 2000年第2期18卷 133-140页

作者： Zi-Luan Wei (Institute of Computational Mathematics and Scientific / Engineerin Computing, Chinese Academy of Sciences, p.O. Box 2719, Beijing 100080, China) 中科院计算数学与科学工程计算所北京 100080

presents information on a study which described a subspace search method for solving a class of least squares problem. Derivation of the algorithm; Convergence results; Modification of algorithm and applications.

关键词： subspace search method A class of least squqres problem convergence analysis.

Training data selection for accuracy and transferability of interatomic potentials

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npj Computational Materials 2022年第1期8卷 1795-1803页

作者： David Montes de Oca Zapiain Mitchell A.Wood Nicholas Lubbers Carlos Zp.ereyra Aidan p.Thompson Danny perez Sandia National Laboratories AlbuquerqueNM87185USA Computer Computationaland Statistical Sciences DivisionLos Alamos National LaboratoryLos AlamosNM87545USA Mechanical and Aerospace Engineering University of California DavisDavisCA95616USA Theoretical Division Los Alamos National LaboratoryLos AlamosNM87545USA

Advances in machine learning(ML)have enabled the development of interatomic potentials that promise the accuracy of first principles methods and the low-cost,parallel efficiency of empirical ***,ML-based potentials struggle to achieve transferability,i.e.,provide consistent accuracy across configurations that differ from those used during *** order to realize the promise of ML-based potentials,systematic and scalable approaches to generate diverse training sets need to be *** work creates a diverse training set for tungsten in an automated manner using an entropy optimization ***,multiple polynomial and neural network potentials are trained on the entropy-optimized dataset.A corresponding set of potentials are trained on an expert-curated dataset for tungsten for *** models trained to the entropy-optimized data exhibited superior transferability compared to the expert-curated ***,the models trained to the expert-curated set exhibited a significant decrease in performance when evaluated on out-of-sample configurations.

关键词： entropy transfer configuration

Effect of vanadium and chromium on the microstructural features of V–Cr–Mn–Ni spheroidal carbide cast irons

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International Journal of Minerals,Metallurgy and Materials 2014年第11期21卷 1096-1108页

作者： V.G.Efremenko K.Shimizu A.p.Cheiliakh T.V.Kozarevskaya K.Kusumoto K.Yamamoto Department of Metal Science and Heat Treatment of Metals Pryazovskyi State Technical UniversityMariupol 87500 Ukraine Manufacturing and Engineering Design Center Muroran Institute of TechnologyMuroran 050-8585 Japan

The objective of this investigation is to study the influence of vanadium（5.0wt%–10.0wt%） and chromium（0–9.0wt%） on the microstructure and hardness of Cr-V-Mn-Ni white cast irons with spheroidal vanadium carbides. The alloys＇ microstructural features are presented and discussed with regard to the distribution of phase elements. The structural constituents of the alloys are spheroidal VC, proeutectoid cementite, ledeburite eutectic, rosette-shaped carbide eutectic（based on M7C3）, pearlite, martensite, and austenite. Their combinations and area fraction（AF） ratios are reported to be influenced by the alloys＇ chemical composition. Spheroidized VC particles are found to be sites for the nucleation of carbide eutectics. Cr and V are shown to substitute each other in the VC and M7C3 carbides, respectively. Chromium alloying leads to the formation of a eutectic（γ-Fe ＋ М7С3）, preventing the appearance of proeutectoid cementite in the structure. Vanadium and chromium are revealed to increase the total carbide fraction and the amount of austenite in the matrix. Cr is observed to play a key role in controlling the metallic matrix microstructure.

关键词： cast irons carbides microstructure vanadium chromium austenite pearlite

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Chemical Research in Chinese Universities 2001年第2期17卷 212-218页

作者： GUO Ming and LIU Wen-jie (Department of Basic Courses, Tarim University of Agricultural Reclamation, Alar, Xinjiang 843300, p. R. China) Tarim Univ Agr Reclamat Dept Basic Courses Alar 843300 Xinjiang Peoples R China

The molecular similarity of 139 organic compounds was calculated by the topologic index method, the flexible super-ball algorithm was used to scan similar molecules and structures. The results show that the properti... 详细信息

关键词： Molecular similarity Super-ball algorithm Calculation