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IEEE/CAA Journal of Automatica Sinica 2021年第8期8卷 1465-1476页

作者： donglei Zheng le Zhou Zhihuan Song State Key Laboratory of Industrial Control Technology College of Control Science and EngineeringZhejiang UniversityHangzhou 310027China Automation and Electrical Engineering Zhejiang University of Science&TechnologyHangzhou 310023China

In practical process industries,a variety of online and offline sensors and measuring instruments have been used for process control and monitoring purposes,which indicates that the measurements coming from different sources are collected at different sampling *** build a complete process monitoring strategy,all these multi-rate measurements should be considered for data-based modeling and *** this paper,a novel kernel multi-rate probabilistic principal component analysis(K-MPPCA)model is proposed to extract the nonlinear correlations among different sampling *** the proposed model,the model parameters are calibrated using the kernel trick and the expectation-maximum(em)***,the corresponding fault detection methods based on the nonlinear features are ***,a simulated nonlinear case and an actual pre-decarburization unit in the ammonia synthesis process are tested to demonstrate the efficiency of the proposed method.

关键词： Fault detection kernel method multi-rate process probability principal component analysis(PPCA)

Finite-difference time-domain studies of low-frequency stop band in superconductor-dielectric superlattice

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Chinese Physics B 2010年第8期19卷 374-378页

作者：王身云刘少斌 le-Wei Joshua Li College of Information Science and Technology Nanjing University of Aeronautics & Astronautics department of Electrical and Computer Engineering National University of Singapore

The transmission coefficients of electromagnetic （em） waves due to a superconductor-dielectric superlattice are numerically calculated. Shift operator finite difference time domain （SO-FdTd） method is used in the analysis. By using the SO-FdTd method, the transmission spectrum is obtained and its characteristics are investigated for different thicknesses of superconductor layers and dielectric layers, from which a stop band starting from zero frequency can be apparently observed. The relation between this low-frequency stop band and relative temperature, and also the London penetration depth at a superconductor temperature of zero degree are discussed, separately. The low-frequency stop band properties of superconductor-dielectric superlattice thus are well disclosed.

关键词： shift operator finite difference time domain method superconductor superconductor- dielectric superlattice high-pass filter

Frequency and Factors Associated with Periodontitis in Congolese Patients: A Cross-Sectional Study

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Open Journal of Stomatology 2021年第1期11卷 55-64页

作者： em Kalala-Kazadi Fidèle Nyimi-Bushabu Hubert Ntumba-Mulumba Michel C. Brecx Periodontology Unit Department of Dental Medicine Faculty of Medicine University of Kinshasa Kinshasa Democratic Republic of Congo Oral Maxillofacial Surgery Head and Neck Oncology Department of Dental Medicine Faculty of Medicine University of Kinshasa Kinshasa Democratic Republic of Congo Prosthodontics and Orthodontics Service Department of Dental Medicine University of Kinshasa Kinshasa Democratic Republic of Congo department of Periodontology Université Catholique de Louvain Brussels Belgium

Background: Periodontitis is a multifactorial disease which is highly prevalent worldwide. The control of periodontal risk factor network is of paramount importance for the management of the disease. Aim: The aim of this study was to assess the frequency and identify the factors associated with periodontitis in Congolese patients. Material and Methods: This cross-sectional study was carried out in four medical centers in the city of Kinshasa between April 2017 and April 2018. The study included patients aged at least 12 years old who consulted the dental services of these centers and who met the inclusion criteria. The participants underwent a structured interview and a clinical periodontal examination. The latter involved the entire dentition, and periodontal pocket and attachment level measurements were taken at six sites per tooth. The plaque and bleeding index were recorded. Logistic regression was used to identify associated factors. The significance level was set at p 0.05. Results: The study included 827 patients and 42% of them had periodontitis. The most represented age group was between 20 and 29 years old. In multivariate analysis, age greater than or equal to 35 years, OR = 2.45 CI 95% (1.77 - 3.45), and the amount of plaque expressed as plaque index ≥ 1, OR = 2 CI 95% (1.31 - 3.07) were factors associated with periodontitis. Conclusion: Factors associated with periodontitis found in this study are age ≥35 years and the amoun

关键词： Associated Factors Periodontitis Frequency Congolese

Analytical form of em fields radiated by circular aperture antennas of various current distributions

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电波科学学报 2005年第1期20卷 1-7页

作者： le-WeiLi QunWu CMRFChairProfessor DeptofElectrical＆ComputerEngineeringDirectorCentreforMicrowave＆RadioFrequencyNationalUniversityofSingapore10KentRidgeCrescentSingapore119260

In this paper, the electromagnetic radiation by circular aperture antennas fed by circular waveguides is considered. Electromagnetic fields radiated by the aperture antennas are formulated in detail and two aperture field distributions are considered, one being the uniform distribution and the other being the TE11-mode distribution. Some mistakes existing in the literature are pointed out. The detailed derivations for the fields by the TE11-mode distribution aperture were not commonly available in the public literature, although the solution is available. The analytical results obtained here are useful for antenna designers and antenna engineering education.

关键词：电磁场辐射圆形波导管裂隙天线电流分布公式化分析

Awareness of Patients toward dental Implants as an Alternative Treatment to Replace Missing Teeth in Kinshasa, d. R. Congo

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Open Journal of Stomatology 2018年第12期8卷 345-353页

作者： em Kalala-Kazadi Patrick disidi-Yakini Fidèle Nyimi-Bushaba Edize Ekofo-Ingaya Augustin Mantshumba-Milolo Unit of Periodontology Department of Dental Medicine Faculty of Medicine University of Kinshasa Kinshasa Congo Oral and Maxillo-Facial Surgery University of Kinshasa and Kinshasa Congo Wuhan University Wuhan China Prosthesis and Orthodontic Service Department of Dental Medicine Faculty of Medicine University of Kinshasa Kinshasa Congo

Background: dental implant is an artificial root inserted in the jawbone, which restores a lost tooth so that it looks, feels, and is fit like a natural tooth. It is considered to be the best treatment option for single or multiple missing teeth. The aim of this study was to assess the awareness of patients about dental implants as an alternative treatment in Congolese patients. Materials and Methods: A cross-sectional study was conducted in two institutions namely, CBCO Bandal and Ngaliema Clinic, from August to december 2017. A total of 450 respondents have participated in the survey. A printed questionnaire comprised of 20 questions in order to evaluate patients dental awareness was used. Gender, level of education, awareness of dental implant and dental implants therapy, sources of information and the expectation about the sources of information were assessed. The collected data were entered in Microsoft Excel 2010 and analyzed by SPSS (IBM SPSS 20.0, Chicago, IL, USA) software. Results: Out of 450 participants, 14.4% were aware of dental implants. The main disadvantage of dental implant was the high cost. When asked about the anchorage, 86% didn’t know where the dental implant was anchored. Ninety-two percent didn’t know for how long an implant last, 6% thought that dental implant last for a lifetime. When patients were asked about the sources of information, the dentist (5%) and media (5.5%) were the main sources of information. The majority of patients (88.4%) would like to get information about dental implants from their dentist. Conclusion: dentists should be more involved in the promotion of information about dental implants as a treatment modality to replace missing teeth.

关键词： Awareness dental Implant Treatment Modality Oral Rehabilitation

N-heterocyclic carbene-stabilized metal nanoparticles within porous organic cages for catalytic application

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National Science Review 2022年第6期9卷 135-142页

作者： Tong Liu Sha Bai le Zhang F.Ekkehardt Hahn Ying-Feng Han Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education Xi'an Key Laboratory of Functional Supramolecular Structure and Materials College of Chemistry and Materials ScienceNorthwest University Institut für Anorganicshe und Analytische Chemie Westf?lische Wilhelms-Universit?t Münster

Tuning the surface-embellishing ligands of metal nanoparticles(NPs) is a powerful strategy to modulate their morphology and surface electronic and functional features, impacting their catalytic activity and selectivity. In this work, we report the design and synthesis of a polytriazolium organic cage PIC-T, capable of stabilizing Pd NPs within its discrete cavity. The obtained material(denoted Pd@PCC-T) is highly durable and monodispersed with narrow particle-size distribution of 2.06 ± 0.02 nm, exhibiting excellent catalytic performance and recyclability in the Sonogashira coupling and tandem reaction to synthesize benzofuran derivatives. Further investigation indicates that the modulation of N-heterocyclic carbene sites embedded in the organic cage has an impact on NPs’ catalytic efficiency, thus providing a novel methodology to design superior NP catalysts.

关键词： metal nanoparticle porous organic cage catalytic reaction N-heterocyclic carbene

SOMO-HOMO level conversion in triarylmethyl-cored N-heterocyclic carbene-Au(I)complexes triggered by selecting coordination halogens

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Chinese Chemical letters 2024年第11期35卷 512-516页

作者： le Zhang Hui-Yu Xie Xin Li Li-Ying Sun Ying-Feng Han Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education Xi'an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi'an 710127China

Conventionally,organic radicals adhere to the Aufbau principle,the energy level of the singly occupied molecular orbital(SOMO)is not below the highest occupied molecular orbital(HOMO),but somewhat abnormal phenomena have appeared *** this study,we introduce a novel strategy by incorporating unique NHC-Au-X units into a tris(2,4,6-trichlorophenyl)methyl(TTM)system to create metal-involved open-shell complexes,denoted as TTM-NHC-Au-X(X=I,Br,or Cl).density-functional theory calculations were used to predict an inversion in the energy of the SOMO and highest doubly occupied molecular orbital(HOMO)of TTM-NHC-Au-I,which is supported by experimental *** radicals TTM-NHC-Au-X demonstrated distinct properties with different coordinated *** radical behaviors have been investigated by EPR,UV-vis spectroscopy and cyclic voltammetry,additional structural information provided by structurally comparing related the precursor complexes given by X-ray ***-NHC-Au-I with SOMO-HOMO conversion(SHC)features a highly thermal decomposition temperature up to 305℃.Furthermore,the photostability of TTM-NHC-Au-I was found to be 75and 23 times greater than that of TTM-NHC-Au-Br and TTM-NHC-Au-Cl,*** findings provide valuable insights into the structural and electronic design principles governing the occurrence of SOMO-HOMO conversion in open-shell systems.

关键词： SOMO-HOMO conversion N-heterocyclic carbenes Aufbau and non-Aufbau Electronic structure Halogen atoms Radical

dynamic Process Monitoring Based on Probabilistic Principle Component Regression

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Dynamic Process Monitoring Based on Probabilistic Principle ...

Changes Induced by Physical Activity, Weight Loss and Calorie Restriction in Body Composition, Lipoproteins and Functional Capacity in Obese Congolese Women

第25届中国控制与决策会议

作者： le Zhou Zhihuan Song Zhiqiang Ge Aimin Miao State Key Laboratory of Industrial Control Technology Zhejiang University

ISBN: (纸本)9781467355339

Probabilistic principal component analysis （PPCA） has been proposed to monitor the industrial process in the probabilistic manner. However, the traditional PPCA method is invalid when the observed data is strongly auto-correlated. For monitoring the probabilistic dynamic process, a probabilistic principal component regression （PPCR） model is proposed to extract the dynamic information of the data, based on which new monitoring statistics are constructed. The Expectation-Maximization （em） algorithm is utilized for model training. Then, the PPCR based state space model is constructed to monitor the dynamic process. For performance evaluation, a case study on the Tennessee Eastman （TE） benchmark process is provided.

关键词： dynamic process monitoring probabilistic principal component regression (PPCR) em algorithm

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Health 2020年第6期12卷 548-571页

作者： Moulongo Jean Georges André Makosso Vheiye Georges Eouani Max Lévy eméry Mouanda Richard le Savant Ndalla Mathias Cyriaque Packa Tchissambou Bernard Massamba Alphonse Laboratory of Sports Biosciences Higher Institute of Physical Education and Sports Marien NGOUABI University Brazzaville Congo Unit of Nutritional Science and Metabolism Higher Institute of Physical Education and Sports Marien NGOUABI University Brazzaville Congo department of Gynecology & Obstetrics Loandjili Hospital Pointe-Noire (Congo) and Faculty of Health Sciences Marien NGOUABI University Brazzaville Congo Clinical Psychology Research division Marien NGOUABI University Brazzaville Congo Biomedical Analyses Center Makelekele Brazzaville Congo Laboratory of Numerical Analysis Computer Science and Applications Faculty of Sciences and Technology Marien NGOUABI University Brazzaville Congo

Background. The effects of physical exercises combined with a low-calorie diet on weight loss, body composition, lipoproteins profile, and physical fitness had been well described. However, Central Africa’s studies investigating these kinds of diets and exercise regimens are lacking. Objective. To investigate the effects of adding 14-weeks exercises to a hypocaloric diet on changes in body composition, lipoproteins concentrations, and physical capacities in obese Congolese women. Population and Methods. In total, 34 obese women aged 30 - 39 years (mean age: 33.7 ± 2.4 years) assigned to 14-weeks training program and low energy ketogenic diet. Body composition was assessed using classic methods and impedancemetry. Fasting plasma glucose (FPG) and fasting serum insulin were assessing using enzymatic colorimetric and radioim-munoradiometric methods. HOMA-IR and lipoproteins concentrations were assessed using standardized laboratory methods. VO2peak was measured on a treadmill during a progressive exercise test. Speed, cadence and stride length were measured along the 10-m level walkway. Muscular endurance was measured using the tests of sit-up and inflections-extensions of elbows. All the variables of the study were assessed at the beginning, in the 7-weeks, and in the 14-weeks of training methods. Results. declines in body weight (16%), percent fat (12.1%), fat weight (26.4%), abdominal fat (34.2%), and waist circumference (10.4%) were found. A significant decrease in FPG (13%), fasting serum insulin (60.9%), HOMA-IR (64.7%), total cholesterol (12.2%), LdL-cholesterol (20.3%), triglycerides (92.8%), and VLdL-triglycerides (17.5%) was shown. In contrast, significant increase in HdL-cholesterol (27.13%) was found. The peak oxygen consumption VO2peak relative to body weight improved more in the 14-weeks training program (13.4%). Obese women exhibited higher values in the 14-weeks training program for speed gait (16.5%), cadence (9.1%), and stride length (15.7%) during no

关键词： Lipoproteins Body Composition Calorie Restriction Physical Exercise Obese Congolese Women

Soil attributes structure plant assemblages across an Atlantic forest mosaic

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Journal of Plant Ecology 2018年第4期11卷 613-622页

作者： Maria Fabíola Barros Bruno X.Pinho Tarciso leão Marcelo Tabarelli Programa de Pós-Graduação em Biologia Vegetal Departamento de BotânicaUniversidade Federal de PernambucoPE 50670-901Brazil department of Forest Resources University of MinnesotaSt.PaulMN 55108USA

Aims Community assembly persists as a key topic in ecology due to the complex variation in the relative importance of assembly forces and mechanisms across spatio-temporal scales and *** we address a forest-savanna vegetation mosaic in the Brazilian Atlantic forest to examine the role played by soil attributes as determinants of community assembly and organiza-tion at a landscape spatial *** We examined soil and plant assemblage attributes across 23 plots of forest and savanna in a 1600 km2 landscape exposed to the same climatic conditions in the Atlantic forest region of northeast *** attributes included species richness,taxonomic and functional composition(community weighted mean,CWM)and functional diversity(quadratic diversity;Rao’s quadratic entropy index)relative to plant leaf area,specific leaf area,leaf dry matter content,thickness and *** Findings Our results suggest that forest and savanna patches exposed to the same climatic conditions clearly differ in terms of soil attributes,plant assemblage structure,taxonomic and functional *** selecting particular plant strategies relative to resource economy,soil potentially affects community structure,with forest assemblages bear-ing more acquisitive resource-use strategies,while conservative plant strategies are more frequent in ***,savanna-forest mosaics in the Atlantic forest region represent spatially organized plant assemblages in terms of taxonomic and functional features,with a sig-nal of trait convergence in both vegetation ***-mediated filter-ing thus emerges as a potential deterministic assembly force affecting the spatial organization of savanna-forest boundaries and mosaics.

关键词： community assembly habitat filtering plant functional traits savanna vegetation tropical forest