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定向管状纤维自修复水泥基复合材料性能研究

定向管状纤维自修复水泥基复合材料性能研究

作者： soro Dogniman Landry（索罗多格·尼曼兰德里）河北工业大学

学位级别：硕士

混凝土开裂是威胁基础设施安全服役的关键问题。混凝土在大型基础设施、工业与民用建筑等工程中长期广泛应用,但由于其抗拉强度低和准脆性,也最容易出现裂缝。结构中的裂缝通常需要定期修复,这不但会使基础设施在一定时期内无法使用,还... 详细信息

混凝土开裂是威胁基础设施安全服役的关键问题。混凝土在大型基础设施、工业与民用建筑等工程中长期广泛应用,但由于其抗拉强度低和准脆性,也最容易出现裂缝。结构中的裂缝通常需要定期修复,这不但会使基础设施在一定时期内无法使用,还会增加工程成本。同时某些裂缝并不能通过人工方法进行修复,如地下结构和放射性废物处理设施。混凝土自修复技术是解决上述问题的方法之一,该方法允许混凝土结构通过自然或人工机制在没有人为干预的情况下自我修复裂缝。基于化学原理来使裂缝自我修复是一种行之有效的方法。因其能够修复一定范围宽度的裂缝,该方法已证明是应用在水泥基材料中最有效的修复方法之一。然而,裂缝自修复一般是向混凝土中掺入含修复剂的胶囊或管状纤维,胶囊或管状纤维随机分布的特性可能使其无法充分接触裂缝,这就限制了其自修复的效果。在本文中,利用内含修复剂的聚偏氟乙烯树脂(PVDF)管状自修复纤维,研究自修复纤维的排列方向对其修复裂缝的能力的影响。首先,研究了PVDF自修复纤维的拉伸强度及其与水泥基体的粘结强度。结果表明,水泥基体发生开裂时,PVDF自修复纤维既具有一定的弹性,同时能够及时开裂以释放其中的修复剂。PVDF自修复纤维和水泥基体之间的粘结强度也能保证纤维开裂而不是发生滑移。其次,研究了PVDF自修复纤维在水泥基体中的定向方法。由于钢纤维可通过磁场力在水泥基体中旋转定向,因此将PVDF自修复纤维与钢纤维结合形成复合纤维。当将掺有复合纤维的拌合物置于匀强磁场中时,钢纤维会因为受到磁场力而发生旋转。相应地,PVDF自修复纤维也会随钢纤维发生旋转。基于此原理,首先制备了两种类型的复合纤维(AHFCC-1SF和AHFCC-2SF,每根自修复纤维上分别绑定一根和两根钢纤维),而后研究了实现混杂纤维定向所需要的最佳的拌合物工作性。结果表明,AHFCC-2SF型纤维定向效果良好,且拌合物工作性(扩展度)应在160-240mm范围。然后,研究了PVDF自修复纤维的排列方向对其修复裂缝能力的影响。首先制备了单向定向(AHFCC)和随机乱向(RHFCC)自修复纤维水泥基复合材料试件,并对每个试件进行了劈拉以使其分别带有270?m和220?mm宽度的裂缝。然后将两种类型的试件养护7天以使裂缝得到修复。修复完成后,测试了两种类型试件的透水性能。结果表明,与RHFCC相比,AHFCC虽然具有较大的裂缝宽度,但其透水能力更低。进一步地,通过劈拉强度测试评价其修复能力。在试件自修复完成后,与RHFCC相比,AHFCC的劈拉强度得到更大程度的恢复。此外,也研究了不同掺量的自修复纤维(体积掺量分别为0%、0.12%和0.18%)对水泥基复合材料抗压强度的影响。结果表明,自修复纤维掺量较高时可能会对抗压强度产生不利影响。综上所述,PVDF自修复纤维与钢纤维结合能够使PVDF自修复纤维跟随钢纤维发生旋转实现定向;沿拉应力分布(垂直于开裂表面)的PVDF自修复纤维显著提高了材料的自修复能力;与RHFCC相比,尽管AHFCC的裂缝宽度更大,但是自修复性能更好;PVDF自修复纤维定向后,能提高跨越裂缝的自修复纤维的数量,开裂时释放更多的修复剂,从而填充或粘结更大裂缝体积(面积)。因此,自修复纤维在基体中定向排列能够有效提高试件的自修复能力。

关键词：自修复修复性能定向修复纤维随机分布修复纤维混杂纤维水泥基复合材料

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书：缓慢阅读

厦门航空 2005年第6期 120-121页

作者： soro

我读书一向很慢，而且潜意识里坚持要有大段大段的时间才能够开始一次阅读，一方面是性情所致，另一方面大概也跟阅读的偏好有关。虽然现在已经沦落到（或者说习惯于）乐于在网上看贴图和灌水笑话，却还是怀念那些静心看文字的光景。从... 详细信息

我读书一向很慢，而且潜意识里坚持要有大段大段的时间才能够开始一次阅读，一方面是性情所致，另一方面大概也跟阅读的偏好有关。虽然现在已经沦落到（或者说习惯于）乐于在网上看贴图和灌水笑话，却还是怀念那些静心看文字的光景。从一大堆书本中找出几本熟悉的名字，写下它们，更重要的是回忆阅读的快感和当时的历史情境，作者的微言大义倒相对次之了。

关键词：阅读潜意识读书历史

Elicitation of Association Rules from Information on Customs Offences on the Basis of Frequent Motives

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Engineering（科研） 2018年第9期10卷 588-605页

作者： Bi Bolou Zehero Etienne soro Yake Gondo Pacome Brou Olivier Asseu Institut National Polytechnique—Houphouet Boigny YamoussoukroCote d’Ivoire Ecole Superieure Africaine des TIC-ESATIC Abidjan-TreichvilleCote d’Ivoire Universite Felix Houphouet Boigny Abidjan-CocodyCote d’Ivoire

The fight against fraud and trafficking is a fundamental mission of customs. The conditions for carrying out this mission depend both on the evolution of economic issues and on the behaviour of the actors in charge of its implementation. As part of the customs clearance process, customs are nowadays confronted with an increasing volume of goods in connection with the development of international trade. Automated risk management is therefore required to limit intrusive control. In this article, we propose an unsupervised classification method to extract knowledge rules from a database of customs offences in order to identify abnormal behaviour resulting from customs control. The idea is to apply the Apriori principle on the basis of frequent grounds on a database relating to customs offences in customs procedures to uncover potential rules of association between a customs operation and an offence for the purpose of extracting knowledge governing the occurrence of fraud. This mass of often heterogeneous and complex data thus generates new needs that knowledge extraction methods must be able to meet. The assessment of infringements inevitably requires a proper identification of the risks. It is an original approach based on data mining or data mining to build association rules in two steps: first, search for frequent patterns (support >= minimum support) then from the frequent patterns, produce association rules (Trust >= Minimum Trust). The simulations carried out highlighted three main association rules: forecasting rules, targeting rules and neutral rules with the introduction of a third indicator of rule relevance which is the Lift measure. Confidence in the first two rules has been set at least 50%.

关键词： Data Mining Customs Offences Unsupervised Method Principle of Apriori Frequent Motive Rule of Association Extraction of Knowledge

3-D Modeling of Temperature Effect on a Polycrystalline Silicon Solar Cell under Intense Light Illumination

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Smart Grid and Renewable Energy 2017年第9期8卷 291-304页

作者： Boubacar soro Martial Zoungrana Issa Zerbo Mahamadi Savadogo Dieudonné Joseph Bathiebo Laboratory of Thermal and Renewable Energies Department of Physics Unit of Training and Research in Pure and Applied Sciences University Ouaga I Prof Joseph KI-ZERBO Ouagadougou Burkina Faso

The efficiency of a silicon solar cell is directly linked to the quantity of carrier photogenerated in its base. It increases with the increase of the quantity of carrier in the base of the solar cell. The carrier density in the base of the solar cell increases with the increase of the flux of photons that crosses the solar cell. One of the methods used to increase the flux of photon on the illuminated side of the solar cell is the intensification of the illumination light. However, the intensification of the light come with the increase of the energy released by thermalization, the collision between carriers, their braking due to the carriers concentration gradient electric field which lead to increase the temperature in the base of the solar cell. This work presents a 3-D study, of the effect of the temperature on the electronic parameters of a polycrystalline silicon solar under intense light illumination. The electronic parameters on which we analyze the temperature effect are:?the mobility of solar cell carriers?(electrons and holes),?their diffusion coefficient, their diffusion length and their distribution in the bulk of the base. To study the effect of the temperature on electronic parameters, we take into account, the dependence of carriers (electrons and holes) mobility with the temperature (μn,(T)?μp(T)). Then, the resolution of the continuity equation,which is a function of the carriers gradient electric field and the carriers mobility,?leads to the expressions of?the diffusion coefficient, the diffusion length, and the density of carriers which are function of the temperature. Then, we studied the effects of the temperature on the diffusion parameters in order to explain their effect on the behavior the carriers distribution in intermediate, short circuit and open circuit operating modes at several positions in the base depth. It appears through this study that the diffusion coefficient and the diffusion length decrease with the increase of the temperat

关键词： Intense Light Electric Field Temperature Diffusion Coefficient Diffusion Length Density of Carriers

Analysis and Comparison of Doping Level Effects on a Crystalline Silicon PV Cell under Both Moderate Light Concentration and Normal Illumination Modes

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Energy and Power Engineering 2022年第10期14卷 523-540页

作者： Mahamadi Savadogo Adama Ouedraogo Boubacar soro Zi Daouda Koudougou Martial Zoungrana Issa Zerbo Laboratory of Thermal and Renewable Energies Department of Physics Unit of Training and Research in Pure and Applied Sciences University Joseph Ki-Zerbo Ouagadougou Burkina Faso Centre Universitaire Polytechnique de Kaya (CUP-Kaya) Kaya Burkina Faso Institut des Sciences et Technologies Ouagadougou Burkina Faso

The main purpose of this work is to study doping level effects on a silicon PV cell under both moderate light concentration and normal illumination. This study also aims to compare the doping level effects under the both illumination modes. The results show for both illumination modes that diffusion parameters decrease with increasing doping level. These results are in agreement with the studies of the current and the voltage which showed for the two illumination modes that doping level increase leads to a decrease in current density and an increase in voltage. It also emerges for the two illumination modes and for the doping range 1013 cm-3 - 1016 cm-3, a decrease of maximum power and conversion efficiency. The results also show that decrease of diffusion parameters is faster under moderate concentration in comparison with normal illumination. These results predict a greater variation rate of the current, the voltage, the maximum power and the conversion efficiency under moderate concentration compared to normal illumination. Contrary to diffusion parameters study, the results show higher variation rates of parameters under normal illumination. This is explained by the fact that under moderate concentration, carriers density is close to doping level: the cell is then in high injection condition. Consequently, under moderate concentration, carriers density is less sensitive to doping level variations. The study confirms that carriers density variation with the doping level is weak under the moderate concentration compared to normal illumination.

关键词： Moderate Light Concentration Doping Level High Injection Diffusion Parameters Conversion Efficiency

Mapping of Potential Recharge Areas of Fractured Aquifers in the Departments of Yamoussoukro and Toumodi (Central Côte d’Ivoire)

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Journal of Geographic Information System 2022年第5期14卷 527-545页

作者： Kouassi Hervé Jacques Kokobou Arthur Brice Konan-Waidhet Tanina Drissa soro Jean Biemi Laboratory of Science and Technology of Environment Jean Lorougnon Guédé University Daloa C&ocirc te d’Ivoire UFR STRM/Felix Houphouet Boigny University Abidjan C&ocirc te d’Ivoire

Groundwater is an important natural resource for all human activity. Today, due to climate change and population growth, the demand has increased considerably, thus requiring their evaluation to ensure sustainability. However, one of the important but difficult to estimate parameters due to its variability is the recharge. This work aims to map the potential recharge of aquifers in the departments of Yamoussoukro and Toumodi. Saaty’s AHP (Analytical Hierarchy Process) multi-criteria analysis technique was used by integrating different thematic layers. First, a reclassification then weighting of these parameters was made according to their influence in the recharge process. Finally, they were integrated into a GIS to produce the map of potential groundwater recharge zones. The results indicate that the potential high recharge areas represent approximately 43.11% of the area of the study area. These areas appear scattered in the sub-prefecture of Yamoussoukro, Kokoumbo Attiegouakro, Toumodi et Kpouèbo.

关键词： Groundwater Recharge Multi-Criteria Analysis GIS Cote d’Ivoire

Efficient Approach for 3D Stationary Optical Solitons in Dissipative Systems

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Journal of Applied Mathematics and Physics 2015年第10期3卷 1239-1248页

作者： A. Konaté E. soro O. Asseu A. Kamagaté P. Yoboué Ecole Supérieure Africaine des Technologies d’Information et de Communication (ESATIC) Abidjan Cote d’Ivoire

We feature the stationary solutions of the 3D complex cubic-quintic Ginzburg-Landau equation (CGLE). Our approach is based on collective variables approach which helps to obtain a system of variational equations, giving the evolution of the light pulses parameters as a function of the propagation distance. The collective variables approach permits us to obtain, efficiently, a global mapping of the 3D stationary dissipative solitons. In addition it allows describing the influence of the parameters of the equation on the various physical parameters of the pulse and their dynamics. Thus it helps to show the impact of dispersion and nonlinear gain on the stationary dynamic.

关键词： Dissipative Solitons Dispersion Nonlinear Gain Collective Variables Approach Complex Cubic-Quintic Ginzburg-Landau Equation (3D) Three-Dimensional Soliton Spatio-Temporal Pulses

A Genetic Algorithm for Overall Designing and Planning of a Long Term Evolution Advanced network

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American Journal of Operations Research 2016年第4期6卷 355-370页

作者： Brou Aguié Pacôme Bertrand Diaby Moustapha soro Etienne Oumtanaga Souleymane Aka Boko Laboratoire des Mathématique Informatique (LMI) Université Nangui Abrogoua (UNA) Abidjan (Axe Adjamé-Abobo) C?te d’Ivoire Laboratoire de Recherche en Informatique et Télécommunication (LARIT) Institut National Polytechnique-Houphouet Boigny (INP-HB) Abidjan C?te d’Ivoire Direction de Recherche et l’Innovation Technologique (DRIT) école Supérieure Africaine des Technologies Information et de la Communication (ESATIC) Abidjan C?te d’Ivoire

In the mobile radio industry, planning is a fundamental step for the deployment and commissioning of a Telecom network. The proposed models are based on the technology and the focussed architecture. In this context, we introduce a comprehensive single-lens model for a fourth generation mobile network, Long Term Evolution Advanced network (4G/LTE-A) technology which includes three sub assignments: cells in the core network. In the resolution, we propose an adaptation of the Genetic Evolutionary Algorithm for a global resolution. This is a combinatorial optimization problem that is considered as difficult. The use of this adaptive method does not necessarily lead to optimal solutions with the aim of reducing the convergence time towards a feasible solution.

关键词： Overall Planning 4G/LTE-A network Genetic Algorithm

Corrective Effect of the Angle of Incidence of the Magnetic Field Intensity on the Performance (Series and Shunt Resistances) of a Bifacial Silicon Solar Cell

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Energy and Power Engineering 2024年第9期16卷 313-323页

作者： Idrissa Sourabié Mahamadi Savadogo Boubacar soro Ramatou Saré Christian Zoundi Martial Zoungrana Issa Zerbo Laboratoire de Chimie Analytique de Physique Spatiale et nergtique (L@CAPSE) Ecole Doctorale Sciences et Technologies Universit Norbert ZONGO Koudougou Burkina Faso Laboratoire dEnergies Thermiques Renouvelables (L.E.T.RE) Ecole Doctorale Sciences et Technologies Universit Joseph KI-ZERBO Ouagadougou Burkina Faso

This article presents a three-dimensional analysis of the impact of the angle of incidence of the magnetic field intensity on the electrical performance (series resistance, shunt resistance) of a bifacial polycrystalline silicon solar cell. The cell is illuminated simultaneously from both sides. The continuity equation for the excess minority carriers is solved at the emitter and at the depth of the base respectively. The analytical expressions for photocurrent density, photovoltage, series resistance and shunt resistance were deduced. Using these expressions, the values of the series and shunt resistances were extracted for different values of the angle of incidence of the magnetic field intensity. The study shows that as the angle of incidence increases, the slopes of the minority carrier density for the two modes of operation of the solar cell decrease. This is explained by a drop in the accumulation of carriers in the area close to the junction due to the fact that the Lorentz force is unable to drive the carriers towards the lateral surfaces due to the weak action of the magnetic field, which tends to cancel out as the incidence angle increases, and consequently a drop in the open circuit photovoltage. This, in turn, reduces the Lorentz force. These results predict that the p-n junction of the solar cell will not heat up. The study also showed a decrease in series resistance as the incidence angle of the magnetic field intensity increased from 0 rad to π/2 rad and an increase in shunt resistance as the incidence angle increased. His behaviour of the electrical parameters when the angle of incidence of the field from 0 rad to π/2 rad shows that the decreasing magnetic field vector tends to be collinear with the electron trajectory. This allows them to cross the junction and participate in the external current. The best orientation for the Lorentz force is zero, in which case the carriers can move easily towards the junction.

关键词： Angle of Incidence Magnetic Field Intensity Bifacial Polycrystalline Silicon Solar Cell Series Resistance Shunt Resistance