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Evaluation of the Effectiveness of the 2019 School-Based Awareness Campaign on Road Driving in the Municipalities of Cotonou and Abomey-Calavi in Benin

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Open Journal of Preventive Medicine 2022年第12期12卷 281-301页

作者： Patrick Makoutode Charles Sossa-Jerome Boris Pleck Dansou Yolaine glele Ahanhanzo Moussiliou Noël Paraiso Ghislain Emmanuel Sopoh Regional Public Health Institute University of Abomey-Calavi Ouidah Benin

Being the leading death cause among young people in the world, road accidents are avoidable through the adoption of simple attitudes and behaviors. Handicap International Non-Governmental Organization (NGO) has launched an awareness campaign in secondary schools in the municipalities of Cotonou and Abomey-Calavito bring young Beninese users to adopt good attitudes and safe behavior while driving on the road. This study aims at assessing the effectiveness of this awareness campaign. It was an evaluative cross-sectional here-elsewhere type study, held in fourteen high schools in the cities of Cotonou and Abomey-Calavi, of which seven benefited from the campaign and seven did not. In each school, students were selected on the basis of two-stage random sampling. 656 students, 309 of whom were sensitized and 347 of whom were not, were included in this study. The campaign was quite effective. Students, teachers, and school officials’ perceptions of the campaign were positive. In addition, the sensitized students had a better level of knowledge (p = 0.001) and reported safer behaviors (p = 0.003) while driving on the road than those who were not aware. Although the effects are positive, they are still very small. Efforts must be continued and much remains to be done.

关键词： Road Accident Campaign High School Student Benin

基于内聚损伤模型的微通道扁管换热器无模弯曲仿真研究

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基于内聚损伤模型的微通道扁管换热器无模弯曲仿真研究

作者： clément LABRUGERE 上海交通大学

学位级别：硕士

空调系统制造过程中的最大成本来源于换热器制造。传统的换热器制造中换热器装配主要依靠钎焊工艺进行,但钎焊有以下缺点:一方面由于需要依靠大型钎焊炉,从而钎焊过程耗能巨大,使得生产成本大幅增加;另一方面,由于钎焊过程需进行加热,... 详细信息

空调系统制造过程中的最大成本来源于换热器制造。传统的换热器制造中换热器装配主要依靠钎焊工艺进行,但钎焊有以下缺点:一方面由于需要依靠大型钎焊炉,从而钎焊过程耗能巨大,使得生产成本大幅增加;另一方面,由于钎焊过程需进行加热,这要求换热器材料在钎焊高温下不易变形。随着在汽车与航空领域越来越广泛的应用,粘接已经被证明能够克服焊接的缺点、高效、稳定地实现复杂系统装配中的不同材料的连接。本文探讨了一种新型的连接方式换热器的弯曲成形性能。采用汽车领域广泛使用的环氧基树脂粘接剂实现微通道换热器中的装配连接,并且该微通道换热器采用无模弯曲成形。本文基于Ls-Dyna显式动力求解器对微通道扁管换热器中的粘接层性能进行了有限元仿真,并采用内聚损伤模型来模拟粘接层材料的弹塑性性能与分层断裂现象。本文通过双悬臂梁试样的端部开口弯曲试验,建立和标定粘接层材料在内聚损伤模型。建立了平行流换热器无模弯曲有限元模型,有限元仿真结果显示所采用的粘接剂强度足够保证无模弯曲的进行,粘接层在微通道扁管换热器的弯曲过程中仅发生塑性变形而未发生失效,并且采用粘接能够很好的限制微通道扁管换热器无模弯曲过程中发生屈曲。本研究首次对粘接型换热器的弯曲成形性能进行了探讨今后需要开展更多的粘接性能试验与换热器弯曲实验。

关键词：折叠微通道扁管弯曲有限元仿真内聚损伤模型 LS-Dyna

Unsupervised Segmentation Method of Multicomponent Images based on Fuzzy Connectivity Analysis in the Multidimensional Histograms

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Engineering（科研） 2011年第3期3卷 203-214页

作者： Sié Ouattara Georges Laussane Loum Alain clément 不详

Image segmentation denotes a process for partitioning an image into distinct regions, it plays an important role in interpretation and decision making. A large variety of segmentation methods has been developed;among them, multidimensional histogram methods have been investigated but their implementation stays difficult due to the big size of histograms. We present an original method for segmenting n-D (where n is the number of components in image) images or multidimensional images in an unsupervised way using a fuzzy neighbourhood model. It is based on the hierarchical analysis of full n-D compact histograms integrating a fuzzy connected components labelling algorithm that we have realized in this work. Each peak of the histo- gram constitutes a class kernel, as soon as it encloses a number of pixels greater than or equal to a secondary arbitrary threshold knowing that a first threshold was set to define the degree of binary fuzzy similarity be- tween pixels. The use of a lossless compact n-D histogram allows a drastic reduction of the memory space necessary for coding it. As a consequence, the segmentation can be achieved without reducing the colors population of images in the classification step. It is shown that using n-D compact histograms, instead of 1-D and 2-D ones, leads to better segmentation results. Various images were segmented;the evaluation of the quality of segmentation in supervised and unsupervised of segmentation method proposed compare to the classification method k-means gives better results. It thus highlights the relevance of our approach, which can be used for solving many problems of segmentation.

关键词： Multicomponent Images Unsupervised Segmentation n-D Histogram Fuzzy Connected Components Labelling n-D Compact Histogram Evaluation of Segmentation Quality

采用基于快速傅里叶变换的谱解法研究Mg-Y合金的变形机理

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采用基于快速傅里叶变换的谱解法研究Mg-Y合金的变形机理

作者： clément Eliott Gin 上海交通大学

学位级别：硕士

在镁中加入钇(Y)可以提高屈服强度和延展性,然而其机理尚不明确。采用模拟的方法可以更加有效的理解变形过程中Y元素的作用。本文采用了晶体塑性的快速傅里叶变换方法(CPFFT)模拟了原位拉伸过程中Mg-3wt.%Y合金在晶粒尺度的变形行为。... 详细信息

在镁中加入钇(Y)可以提高屈服强度和延展性,然而其机理尚不明确。采用模拟的方法可以更加有效的理解变形过程中Y元素的作用。本文采用了晶体塑性的快速傅里叶变换方法(CPFFT)模拟了原位拉伸过程中Mg-3wt.%Y合金在晶粒尺度的变形行为。结果表明,CPFFT成功预测了拉伸曲线,并可以预测特定晶粒在不同加载步下的取向演变和应力演变。相比于基于位错的弹性粘塑性自洽(EVPSC)模型,CPFFT有效的预测晶粒中的晶粒旋转和应力变化。最后,对模拟结果与实验结果在晶粒旋转和应力方面的误差原因进行了讨论

关键词：镁合金晶体塑性显微组织谱解法 CPFFT

Phytochemical analyses, antimicrobial and antioxidant activities of stem bark extracts of Distemonanthus benthamianus H. Baill. and fruit extracts of Solanum torvum Sw. from Gabon

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Asian Pacific Journal of Tropical Biomedicine 2019年第5期9卷 209-216页

作者： Cédric Sima Obiang Rick Léonid Ngoua Meye Misso Guy Roger Ndong Atome Joseph Privat Ondo Louis clément Obame Engonga Edouard Nsi Emvo Laboratory of Research in Biochemistry University of Sciences and Technology of Masuku Laboratory of Natural Substances and Organometallic Synthesis University of Sciences and Technology of Masuku

Objective: To evaluate the phytochemical constituents, antimicrobial and antioxidant activities of the extracts of Distemonanthus benthamianus(D. benthamianus) stem bark and Solanum torvum(S. torvum) fruit which have been used as traditional medicinal herbs in Gabon. Methods: Plant extracts were subjected to a qualitative study(phytochemical screening) and a quantitative(dosing) study of secondary metabolites. Antioxidant activity was tested by 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azino-bis 3-ethylbenzothiazoline-6-sulfonic acid assay. Bacteria and fungi susceptibility tests were performed on Mueller Hinton medium and solid Sabouraud, respectively, using the diffusion method, while minimum inhibitory concentration, minimum fungicidal concentration and minimum bactericidal concentration were evaluated by microdilution ***: The total phenol and tannin contents were significantly higher in the water-ethanol extract compared to the other extracts of D. benthamianus and S. torvum. The water-ethanol and water-acetone extracts showed significantly higher antioxidant activity than the aqueous extracts of the two medicinal plants. However, the extracts presented weak antioxidant activities compared to standards(Vitamin C, BHA). The water-acetone and water-ethanol extracts of S. torvum showed the highest antimicrobial activity against Bacillus cereus LMG 13569 BHI, Shigella dysenteriae 5451 CIP, Shigella dysenteriae and Neisseria gonorrhoeae. Conclusions: Our results show that D. benthamianus and S. torvum can be promising sources of natural products with potential antimicrobial and antioxidant activities.

关键词： Antioxidants Phytochemical Antimicrobial Distemonanthus benthamianus Solanum torvum

Analysis and Evaluation of MPLS Network Performance

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Communications and Network 2021年第1期13卷 25-35页

作者： Fontaine Rafamantanantsoa Razafindramonja clément Aubert Rabetafika Louis Haja University of Fianarantsoa Fianarantsoa Madagascar

Currently, the increasing network connectivity is becoming more and more complex and the integration of several services continues to appear. These approaches need a guarantee in terms of throughput, the performance of which they potentially impact. So, the basic aim of this research is to get the best MPLS network performance towards linux and FreeBSD operating systems. This is why in this report, we have worked on MPLS network performance, which will help to identify performance metrics. To evaluate the performance, we used those operating systems implementing the MPLS architecture in order to define the best performing between the two on this domain. For this, we used scapy to measure the response times by varying the size of the packets sent and validate the measurements with the MATLAB Simulink. After all experiments, we realized that FreeBSD operating system is more reliable than linux in MPLS network base.

关键词： MPLS Simulink Scapy Performance

Development of a Ready-to-Use PSMA-11 Kit Formulation and Biological Evaluation of Binding Affinity

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Advances in Molecular Imaging 2024年第2期13卷 7-22页

作者： Maria Renata Valente Brandão Freire Natália Marchesan Bexiga Marco Antonio Stephano João Ezequiel Oliveira Carlos Roberto Jorge Soares Ana cláudia Camargo Miranda Anna Carolina de Alcântara Barbosa Marycel Figols de Barboza Laura Fernanda Garcia Luiz Felipe S. Teixeira Maria Helena Marumo Bellini Natanael Gomes da Silva Luiza Mascarenhas Balieiro Joel Mendes Elaine Bortoleti de Araújo Centro de Radiofarmcia Instituto de Pesquisas Energticas e Nucleares (IPEN) Cidade Universitria So Paulo Brasil Departamento de Tecnologia Farmacutica Faculdade de Cincias Farmacuticas (USP) Cidade Universitria So Paulo Brasil Centro de Biotecnologia Instituto de Pesquisas Energticas e Nucleares (IPEN) Cidade Universitria So Paulo Brasil Departamento de Medicina Nuclear do Hospital Israelita Albert Einstein So Paulo/SP Brasil

Introduction: 68Ga-PSMA-11 is considered the gold standard in detection of micro and oligometastases in advanced prostate cancer, being used for therapeutic planning, as well as, potentially, for evaluating response to treatment. The development of ready-to-use lyophilized kit of PSMA-11 adds quality and safety to the routine use of this radiopharmaceutical and represents a pharmacotechnical challenge as it must preserve the integrity and specificity of the ligand. Methods: PSMA-11 kit formulation was proposed, considering radiolabeling parameters and the preservation of the peptide during the lyophilization process, using mannitol as an excipient. Critical temperature characterization studies were carried out using DSC equipment and the freeze-drying process was developed. The direct radiolabeling conditions were evaluated and standardized using 68Ge/68Ga generator eluate from two different manufacturers (ITG and Eckert & Ziegler). The radiochemical purity was evaluated by TLC and HPLC. Biological evaluation was carried out with lyophilized PSMA-11 to demonstrate the integrity of the peptide and preservation of biological activity after the lyophilization process. Results: Based on critical temperature characterization studies, the freeze-drying cycle was designed to reach a freezing temperature of around −40˚C and primary drying at 2˚C. Using 20 mg of mannitol, an intact and elegant lyophilized cake was obtained. PSMA-11 lyophilized kit was directly labeled with 68Ga eluate from 68Ge/68Ga GMP generators (ITG and Eckert & Ziegler) resulting in % RP > 95% at pH 4.0 to 4.5. The results obtained from in vitro and in vivo biological competition studies confirmed the preservation of PSMA-11 affinity for the receptor after lyophilization. Conclusion: A lyophilized formulation (Kit) of PSMA-11 was successfully obtained, which preserved the integrity and biological activity of the peptide and guaranteed radiolabeling efficiency.

关键词： 68Ga-PSMA-11 Prostate-Specific Membrane Antigen (PSMA) Ready-to-Use Kit GMP-Grade Generators Metastatic Prostate Cancer PET Imaging

Performance of a New Method of Multicomponent Images Segmentation in the Presence of Noise

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Engineering（科研） 2011年第11期3卷 1082-1089页

作者： Sié Ouattara Olivier Asseu Alain clément Bertrand Vigouroux 不详

Any undesirable signal limiting to a degree or another the integrity and the intelligibility of a useful signal can be considered as noise. In the general rule, the good performance of a system is assured only if the level of power of the useful signal exceeds by several orders of magnitude that of the noise (signal to noise of a several tens of decibels). However certain elaborate methods of treatment allow working with very low signal to noise ratio in an optimal way any a priori knowledge available on the signal useful to interpret. In this work, we evaluate the robustness of the noise on a new method of multicomponent image segmentation developed recently. Two types of additional noises are considered, which are the Gaussian noise and the uniform noise, with varying correlation between the different components (or planes) of the image. Quantitative results show the influence of the noise level on the segmentation method.

关键词： Multicomponent Images Segmentation n-D Compact Histogram Additional Noise Gaussian Noise Uniform Noise Correlated Noise

PIECEWISE RATIONAL APPROXIMATIONS OF REAL ALGEBRAIC CURVES

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Journal of Computational Mathematics 1997年第1期15卷 55-71页

作者： Bajaj, cl Xu, GL PURDUE UNIV DEPT COMP SCIW LAFAYETTEIN 47907 CHINESE ACAD SCI STATE KEY LAB SCI & ENGN COMPICMSECBEIJINGPEOPLES R CHINA

We use a combination of both algebraic and numerical techniques to construct a C-1-continuous, piecewise (m, n) rational epsilon-approximation of a real algebraic plane curve of degree d. At singular points we use the classical Weierstrass Preparation Theorem and Newton power series factorizations, based on the technique of Hensel lifting. These, together with modified rational Pade approximations, are used to efficiently construct locally approximate, rational parametric representations for all real branches of an algebraic plane curve. Besides singular points we obtain an adaptive selection of simple points about which the curve approximations yield a small number of pieces yet achieve C-1 continuity between pieces. The simpler cases of C-1 and C-0 continuity are also handled in a similar manner. The computation of singularity, the approximation error bounds and details of the implementation of these algorithms are also provided.

关键词： Math ACM PIECEWISE RATIONAL APPROXIMATIONS OF REAL ALGEBRAIC CURVES Design der