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Obtaining the Band Structure of a Two-Dimensional Photonic Crystal by an Averaged Field Approach

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Chinese Physics Letters 2000年第5期17卷 352-354页

作者：何赛灵仇旻 constantin R.Simovski State Key Laboratory of Modern Optical Instrumentation Center for Optical and Electromagnetic ResearchZhejiang UniversityHangzhou 310027 Department of Electromagnetic Theory Royal Institute of TechnologyS-10044 StockholmSweden Department of Physics State Institute of Fine Mechanics and Optics197101 St-PetersburgRussia

An averaged field approach is suggested for obtaining the band structure of a photonic crystal when the dimension of the inclusions is much smaller compared with the longest period of the rectangular lattice of the photonic *** method is illustrated for the H-polarization of the 2-dimensional *** band structure is obtained in an explicit and simple *** method is verified numerically by comparing with the conventional plane-wave expansion method.

关键词： polarization Crystal structure

Topology-preserving flocking of nonlinear agents using optimistic planning

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Control Theory and Technology 2015年第1期13卷 70-81页

作者： Lucian BU?ONIU Irinel-constantin MORRESCU Department of Automation Technical University of Cluj-NapocaMemorandumului 28 400114 Cluj-Napoca Romania Université de Lorraine CRAN UMR 7039 and CNRS CRAN UMR 7039 2 Avenue de la Forêt de HayeVandoeuvre-lès-Nancy France

We consider the generalized flocking problem in multiagent systems, where the agents must drive a subset of their state variables to common values, while communication is constrained by a proximity relationship in terms of another subset of variables. We build a flocking method for general nonlinear agent dynamics, by using at each agent a near-optimal control technique from artificial intelligence called optimistic planning. By defining the rewards to be optimized in a well-chosen way, the preservation of the interconnection topology is guaranteed, under a controllability assumption. We also give a practical variant of the algorithm that does not require to know the details of this assumption, and show that it works well in experiments on nonlinear agents.

关键词： Multiagent systems flocking optimistic planning topology preservation

Palladium-Catalyzed Carbonylation of Multifunctionalized Substituted Alkynes to Quinolinone Derivatives under Mild Conditions

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Chinese Journal of Chemistry 2023年第23期41卷 3223-3228页

作者： Aleksandr Voronov Francesco Pancrazzi Ana Maria constantin Raimondo Maggi Raffaella Mancuso Bartolo Gabriele Diego Olivieri Carla Carfagna Alessandro Casnati Francesco Rispoli Laura Baldini Nicola Della Ca Department of Chemistry Life Sciences and Environmental Sustainability (SCVSA)University of ParmaParco Area delle Scienze17/A43124 Parma (PR)Italy Center for Energy and Environment (CIDEA) University of ParmaParco Area delle Scienze 181/A43124 Parma (PR)Italy Laboratory of Industrial and Synthetic Organic Chemistry (LISOC) Department of Chemistry and Chemical TechnologiesUniversity of CalabriaVia P.Bucci 12/C87036 Arcavacata di RendeCosenza (CS)Italy Department of Biomolecular Sciences University of Urbino “Carlo Bo”Piazza Rinascimento 661029 Urbino (PU)Italy Department of Industrial Chemistry “T.Montanari” University of BolognaViale Risorgimento 440136 Bologna (BO)Italy

A highly selective palladium-catalyzed carbonylation of 2-alkynylanilines bearing an amide moiety to condensed six-membered heterocyclic structures has been developed under mild conditions(room temperature and atmospheric pressure of CO).The carbonylative protocol is also compatible with CO surrogates,such as benzene-1,3,5-triyl triformate(TFBen)or the newly developed calix[6]arenes functionalized with six formate groups(CLX[6]CO),which are both capable to release CO in situ.A series of tricyclic fused heterocycles containing the important oxazino-quinolinone scaffold have been selectively obtained(only the 6-endo-dig cyclization mode has been observed)in good to excellent yields(up to 99%).

关键词： Pd-catalysis Carbonylation Alkynes CO surrogates 6-endo-dig Calixarenes C1 building blocks Domino reactions

Synthesis and performance of Zn–Ni–P thin films

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Chinese Physics B 2015年第3期24卷 259-268页

作者： V.Soare M.Burada I.constantin M.Ghita V.constantin F.Miculescu A.M.Popescu New Materials and Technologies Laboratory National Research and Development Institute for Nonferrous and Rare Metals-IMNR Institute of Physical Chemistry "Ilie Murgulescu" Laboratory of Molten Salts University Polytehnica of Bucharest Center of Biomaterials (BIOMAT)

The electroplating of Zn–Ni–P thin film alloys from a sulfate bath containing phosphoric and phosphorous acid was investigated. The bath composition and the deposition parameters were optimized through Hull cell experiments, and the optimum experimental conditions were determined（p H = 2, temperature = 298–313 K, zinc sulfate concentration =30 g·L^-1, EDTA concentration = 15 g·L^-1, and current density = 1.0–2.0 A·dm^-2）. The SEM analysis of the coating deposited from the optimum bath revealed fine-grained deposits of the alloy in the presence of EDTA. Optical microscopy analysis indicated an electrodeposited thin film with uniform thickness and good adhesion to the steel substrate. The good adherence of the coatings was also demonstrated by the scratch tests that were performed, with a maximum determined value of 25 N for the critical load. Corrosion resistance tests revealed good protection of the steel substrate by the obtained Zn–Ni–P coatings, with values up to 85.89% for samples with Ni contents higher than 76%. The surface analysis of the thin film samples before and after corrosion was performed by X-ray photoelectron spectroscopy（XPS）.

关键词： thin film corrosion electrochemistry surface

A Review on Urinary Incontinence after Surgery for Benign Prostatic Hyperplasia

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Open Journal of Urology 2022年第3期12卷 169-184页

作者： constantin Martial Essissima Foé Yunfen Liao Guoxi Zhang First Affiliated Hospital of Gannan Medical University Ganzhou China

Background: Benign prostatic hyperplasia (BPH) is characterized by the abnormal proliferation of cells, leading to structural changes. It is one of the most common diseases in ageing men. Its clinical presentations are dominated by lower urinary tract symptoms (LUTS). The therapeutic methods can be grouped into two options: the medical option and the surgical option in which prostate enucleation is found. In recent years many studies have reported the onset of urinary incontinence (UI) after prostate enucleation. The management of UI occurring after prostate enucleation is embarrassing for both the practitioner and the patient, and generates additional costs. Purpose: Cite the causes of UI after prostate enucleation for BPH, as well as ways to prevent the onset of UI after this surgery, specifically by the study of the vesicosphincteric system aimed at improving the technique of enucleation;our review will also deal with the therapeutic means of UI. Method: We retrieved studies from Science Direct, Wiley and Pubmed. Results: There are multiple etiologies of UI after prostate enucleation including urethral sphincter insufficiency (USI) and bladder dysfunction (BD). The management of UI after surgery could be conservative, surgical, or use new technologies. Urodynamic assessment before prostate enucleation for BPH is relevant. Conclusion: UI is a common post-operative complication of prostate enucleation. The study of the vesicosphincteric system leads us to believe that prostate enucleation for BPH, partially sparing the mucosa and the external urethral sphincter could decrease the incidence of UI after surgery.

关键词： Benign Prostatic Hyperplasia (BPH) Urinary Incontinence (UI) Urethral Sphincter Insufficiency (USI) Bladder Dysfunction (BD) Detrusor Overactivity (DO) Prostate Enucleation

AS-Index： A Structure for String Search Using n-Grams and Algebraic Signatures

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Journal of Computer Science & Technology 2016年第1期31卷 147-166页

作者： Camelia constantin Cedric du Mouza Witold Litwin Philippe Rigaux Thomas Schwarz LIP6 Laboratory University Pierre et Marie Curie Paris 75005 France CEDRIC Laboratory Conservatoire National des Arts et Metiers Paris 75003 France LAMSADE Laboratory University Paris-Dauphine Paris 75775 France DICC Laboratory Universidad Catolica del Uruguay Montevideo 11200 Uruguay

We present the AS-Index, a new index structure for exact string search in disk resident databases. AS-Index relies on a classical inverted file structure, whose main innovation is a probabilistic search based on the properties of algebraic signatures used for both n-grams hashing and pattern search. Specifically, the properties of our signatures allow to carry out a search by inspecting only two of the posting lists. The algorithm thus enjoys the unique feature of requiring a constant number of disk accesses, independently from both the pattern size and the database size. We conduct extensive experiments on large datasets to evaluate our index behavior. They confirm that it steadily provides a search performance proportional to the two disk accesses necessary to obtain the posting lists. This makes our structure a choice of interest for the class of applications that require very fast lookups in large textual databases. We describe the index structure, our use of algebraic signatures, and the search algorithm. We discuss the operational trade-offs based on the parameters that affect the behavior of our structure, and present the theoretical and experimental performance analysis. We next compare the AS-Index with the state-of-the-art alternatives and show that 1） its construction time matches that of its competitors, due to the similarity of structures, 2） as for search time, it constantly outperforms the standard approach, thanks to the economical access to data complemented by signature calculations, which is at the core of our search method.

关键词： full text indexing large-scale indexing algebraic signature

Real-time hybrid simulation of structures equipped with viscoelastic-plastic dampers using a user-programmable computational platform

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Earthquake Engineering and Engineering Vibration 2017年第4期16卷 693-711页

作者： Jack Wen Wei Guo Ali Ashasi-Sorkhabi Oya Mercan constantin Christopoulos Kinetica 1235 Bay St.Suite 1004ONM5R 3K4 Department of Civil Engineering University of Waterloo200 University Avenue WWaterlooONN2L 3G1Canada Department of Civil Engineering University of Toronto35 St.George StreetTorontoONM5S 1A4Canada

A user-programmable computational/control platform was developed at the University of Toronto that offers real-time hybrid simulation （RTHS） capabilities. The platform was verified previously using several linear physical substructures. The study presented in this paper is focused on further validating the RTHS platform using a nonlinear viscoelastic-plastic damper that has displacement, frequency and temperature-dependent properties. The validation study includes damper component characterization tests, as well as RTHS of a series of single-degree-of-freedom （SDOF） systems equipped with viscoelastic-plastic dampers that represent different structural designs. From the component characterization tests, it was found that for a wide range of excitation frequencies and friction slip loads, the tracking errors are comparable to the errors in RTHS of linear spring systems. The hybrid SDOF results are compared to an independently validated thermal- mechanical viscoelastic model to further validate the ability for the platform to test nonlinear systems. After the validation, as an application study, nonlinear SDOF hybrid tests were used to develop performance spectra to predict the response of structures equipped with damping systems that are more challenging to model analytically. The use of the experimental performance spectra is illustrated by comparing the predicted response to the hybrid test response of 2DOF systems equipped with viscoelastic-plastic dampers.

关键词： real-time hybrid simulation user-programmable computational/control platform supplemental dampers performance spectra

Synthesis,characterization and thermolysis of lanthanide metal nitrate complexes with 1,10-phenanthroline,Part-95

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Journal of Rare Earths 2014年第6期32卷 545-552页

作者： Nibha B.P.Baranwal Gurdip Singh constantin G.Daniliuc Department of Chemistry DDU Gorakhpur University Organisch–Chemisches Institut Universitat Munster

The nitrate complexes of cerium, praseodymium and neodymium with 1,10-phenanthroline （phen） of general formula [Ln（phen）2（NO3）2（H2O）2]·NO3 （where, Ln=Ce, Pr and Nd） were prepared and characterized by X-ray crystallography. Thermolysis of these complexes was investigated by simultaneous thermogravimetry （TG） and differential thermal analysis （DTA）. Isothermal TG was taken to evaluate the kinetic parameters using model fitting as well as model free isoconversional methods. The thermolytic pathways were also suggested, which involves decomposition followed by ignition. All the three complexes had coordination number ten and showed multistep decompositions. In order to evaluate the response of rapid heating, ignition delay （Di） measurements were undertaken. The activation energies for ignition were found to decrease in the order： Nd〉Pr〉Ce.

关键词： crystal structure metal nitrate kinetics isoconversional model fitting ignition delay rare earths

The human retinal stem niches could overlap a vascular anatomical pattern

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Neural Regeneration Research 2015年第1期10卷 39-40页

作者： Mugurel constantin Rusu Alexandra Diana Vrapciu Division of Anatomy Faculty of Dental Medicine"Carol Davila" University of Medicine and Pharmacy MEDCENTER Center of Excellence in Laboratory Medicine and Pathology International Society of Regenerative Medicine and Surgery (ISRMS)

Stem cells are undifferentiated cells which have the unique potential to self-renew and to supply, via intermediate stages of transit amplifying cells （TACs）, differentiated cells. With- in the stem cell niches not only heterologous cells, but also differentiated progeny of stem cells provide regulation to the stem cells parents. Stem cells can differentiate in various cell types during tissue maintenance or repair.

关键词： stem cell The human retinal stem niches could overlap a vascular anatomical pattern MSCs Figure