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Neuro-fuzzy and model-based motion control for mobile manipulator among dynamic obstacles

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Science in China(Series F) 2003年第1期46卷 14-30页

作者：魏武 jean bosco Mbede 黄心汉张毅 Department of Automation Tsinghua University Departement des Genies Industrie Universit de Yaound I Ecole Nationals Superieure Polytechnique Department of Control Science and Engineering Huazhong University of Science and Technology

This paper focuses on autonomous motion control of a nonholonomic platform with a robotic arm, which is called mobile manipulator. It serves in transportation of loads in imperfectly known industrial environments with unknown dynamic obstacles. A union of both procedures is used to solve the general problems of collision-free motion. The problem of collision-free motion for mobile manipulators has been approached from two directions, Planning and Reactive Control. The dynamic path planning can be used to solve the problem of locomotion of mobile platform, and reactive approaches can be employed to solve the motion planning of the arm. The execution can generate the commands for the servo-systems of the robot so as to follow a given nominal trajectory while reacting in real-time to unexpected events. The execution can be designed as an Adaptive Fuzzy Neural Controller. In real world systems, sensor-based motion control becomes essential to deal with model uncertainties and unexpected obstacles.

关键词： autonomous mobile manipulators dynamic obstacle avoidance dynamic path planning model and sensor-based control neuro-fuzzy controller nonholonomic and redundant systems.

智能RLED动态目标中机器手的模糊鲁棒控制系统(英文)

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控制理论与应用 2001年第6期18卷 871-875,881页

作者：魏武黄心汉 jean bosco Mbede 长沙交通学院道路与交通工程系长沙410076 华中科技大学控制科学与工程系武汉430074

给出了一种电机驱动机器手中非线性机电模型的模糊鲁棒闭环控制系统 ,此控制系统可处理非结构环境下的三个主要的智能机器人导航问题 :自动化规划、快速连续导航中的避障、处理结构和 (或 )

关键词： RLED 机器手动态目标电机驱动模糊鲁棒控制系统

New Optimal Pivot Rule for the Simplex Algorithm

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Advances in Pure Mathematics 2016年第10期6卷 647-658页

作者： jean bosco Etoa Etoa Department of Economic and Management Sciences University of Yaounde II Soa Cameroon

The purpose of this paper is to introduce a new pivot rule of the simplex algorithm. The simplex algorithm first presented by George B. Dantzig, is a widely used method for solving a linear programming problem (LP). One of the important steps of the simplex algorithm is applying an appropriate pivot rule to select the basis-entering variable corresponding to the maximum reduced cost. Unfortunately, this pivot rule not only can lead to a critical cycling (solved by Bland’s rules), but does not improve efficiently the objective function. Our new pivot rule 1) solves the cycling problem in the original Dantzig’s simplex pivot rule, and 2) leads to an optimal improvement of the objective function at each iteration. The new pivot rule can lead to the optimal solution of LP with a lower number of iterations. In a maximization problem, Dantzig’s pivot rule selects a basis-entering variable corresponding to the most positive reduced cost;in some problems, it is well-known that Dantzig’s pivot rule, before reaching the optimal solution, may visit a large number of extreme points. Our goal is to improve the simplex algorithm so that the number of extreme points to visit is reduced;we propose an optimal improvement in the objective value per unit step of the basis-entering variable. In this paper, we propose a pivot rule that can reduce the number of such iterations over the Dantzig’s pivot rule and prevent cycling in the simplex algorithm. The idea is to have the maximum improvement in the objective value function: from the set of basis-entering variables with positive reduced cost, the efficient basis-entering variable corresponds to an optimal improvement of the objective function. Using computational complexity arguments and some examples, we prove that our optimal pivot rule is very effective and solves the cycling problem in LP. We test and compare the efficiency of this new pivot rule with Dantzig’s original pivot rule and the simplex algorithm in MATLAB environment.

关键词： Linear Programming Simplex Algorithm Pivot Rules Optimal Pivot Rule

Gestational Diabetes Mellitus and Its Associated Risk Factors in Pregnant Women at Selected Health Facilities in Kigali City, Rwanda

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Journal of Diabetes Mellitus 2016年第4期6卷 269-276页

作者： jean Baptsite Niyibizi Florien Safari jean bosco Ahishakiye jean bosco Habimana Herbert Mapira Ngule Chrispus Mutuku Pan African University Institute of Sciences Technology and Innovation Nairobi Kenya Nyagatare Hospital Nyagatare Rwanda Rwinkwavu Hospital Kayonza Rwanda Gisenyi Hospital Rubavu Rwanda College of Medicine and Health Sciences University of Rwanda Kigali Rwanda Center for Traditional Medicine and Drugs Research Kenya Medical Research Institute Nairobi Kenya

Background: Gestational Diabetes Mellitus (GDM) is the most common complication of pregnancy that causes chronic hypertension, increased rate of cesarean delivery, fetal mortality and morbidity. Therefore, early diagnosis of GDM is vital to reduce maternal and fetal morbidity. Moreover, it can circumvent or procrastinate the onset of type 2 diabetes. Objectives: The main objective of this study was to determine the prevalence of GDM in pregnant women attending Kimironko, Kicukiro and Muhima Health Centres. The specific objectives were to determine the blood glucose during the second trimester in pregnant women aged between 21 and 45 years, to find out the frequencies of pregnant women presenting with GDM according to age and to assess some promising risk factors associated with GDM. Methods: A cross-sectional study was carried out at Kimironko, Kicukiro and Muhima Health centers using a sample size of 96 pregnant women. Blood glucose levels were measured using glucose oxidase method with a glucometer. Data were analyzed by using Microsoft Office Excel and SPSS version 20. Results: Out of 96 pregnant women who participated in the study, 8.3% were found to have GDM with the mean ± 2SD of 194.12 ± 25.53 mg/dl of their blood glucose results (Mean ± 2SD: A 95% level of confidence Intervals). The highest proportion of GDM was revealed in pregnant women aged between 26 - 30 years, representing a frequency of 5.2% whereas 2.1% of GDM was reflected in women aged between 21 - 25 years. The lowest proportion of GDM fell in age group of 31 - 35 years contributing to 1% of the total GDM. There were no cases of GDM in pregnant women in the 36 - 40 or 41 - 45 age groups. The mean ± 2SD of participant’s age groups was 27.12 ± 5.01 years. In addition, while obesity did not show to be associated with GDM, age and family history were found to be risk factors of GDM. Conclusion: The findings of this study revealed that the prevalence of GDM was 8.3% and the most affected pregnant women

关键词： Gestational Diabetes Mellitus (GDM) Prevalence Pregnancy Age Group Risk Factors

Geochemical characterization of the metasedimentary rocks of the Yaounde Group within the southernmost North Equatorial tectonic belt:insights into geodynamic evolution

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Acta Geochimica 2023年第6期42卷 1017-1034页

作者： Simon Pierre Mbola Ndzana Moise Christian Balla Ateba Germain Marie Monespérance Mboudou Moussa Nsangou Ngapna jean Paul Sep Nlongang Solange Ipan Moise Bessong jean bosco Olinga Joseph Mvondo Ondoa Sébastien Owona Paul Bilong Department of Earth Sciences Faculty of ScienceUniversity of YaoundéIP.O.Box:812Yaounde´Cameroon Institute for Geological and Mining Research P.O.Box:4110NlongkakYaounde´Cameroon Department of Earth Sciences Faculty of ScienceUniversity of DoualaP.O.Box:24157DoualaCameroon Department of Geology Faculty of ScienceThe University of BueaP.O.Box:67BueaCameroon

The Proterozoic metasedimentary rocks of the Yaounde Group on the northern edge of the Congo Shield in Central Africa were investigated to understand their provenance and depositional ***,geochemistry,and field evidence helped to subdivide the metasediments into paragneiss,mica schist,chlorite schist,and quartzite which were derived from greywacke,shale,quartz arenite,litharenite *** are immature with some mature samples,moderately weathered and reworked Neo-and Post-Archean *** earth element signatures(Chondrite Eu/Eu^(*)≤1),enrichment of light rare earth elements over the heavy ones,and the La/Sc ratio(>0.7)are compatible with those of the intermediate and felsic sources from the upper continental *** metasediments were deposited in the continental arc setting and have evolved during Proterozoic times according to the Wilson cycle to form the West Gondwana including NE Brazil.

关键词： West Gondwana North Equatorial orogenic belt Yaounde Group Neoproterozoic basin Geochemistry of metasedimentary rocks Geodynamic evolution

新分离苍白杆菌L1-W对DEHP的生物降解：鉴定和降解动力学

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新分离苍白杆菌L1-W对DEHP的生物降解：鉴定和降解动力学

作者： Nshimiyimana,jean bosco 华中师范大学

学位级别：硕士

邻苯二甲酸酯（Phthalates,PAEs）类化合物,主要用于增塑剂中,以提高各种日常用品的弹性、柔软性和耐久性,其中,邻苯二甲酸二（2-乙基己）酯（di-（2-ethylhexyl）-phthalate,DEHP）使用最为广泛。DEHP主要用于制造聚氯乙烯（Polyvinyl ... 详细信息

邻苯二甲酸酯（Phthalates,PAEs）类化合物,主要用于增塑剂中,以提高各种日常用品的弹性、柔软性和耐久性,其中,邻苯二甲酸二（2-乙基己）酯（di-（2-ethylhexyl）-phthalate,DEHP）使用最为广泛。DEHP主要用于制造聚氯乙烯（Polyvinyl Chloride,PVC）相关产品,另外,它还用于制造鞋履、浴帘、医疗器械、衣服、床上用品、胶凝剂、产品包装、建筑材料、粘合剂和儿童玩具。虽然DEHP在生产生活中用途十分广泛,但DEHP也会对产生健康不利影响,这是因为DEHP其实是一种内分泌干扰激素,它会干扰生物的正常生理功能。据报道,在人类和其他动物中,DEHP均会引起机体发生生殖、呼吸或者发育缺陷,并且水解和光解都无法从已污染的环境中去除DEHP,因此生物降解成为消除DEHP污染和修复环境最为有效的方法。本研究的目的是分离、鉴定DEHP高效降解菌株,该菌株能将DEHP作为唯一碳源。我们从武汉市南湖收集了土壤样品和水样,经过处理分离得到L1-W菌株,通过形态学、生理学、16S rDNA测序等方法鉴定出L1-W为苍白杆菌属。当温度为30℃,pH为6.0,DEHP浓度为400mg/L时,L1-W降解DEHP的效率最高。另外,L1-W具有很强的耐盐能力,在盐浓度为10%依旧能发挥降解效力,这使L1-W成为修复盐环境的理想选择之一,且无需额外的淡化成本。此外,L1-W能降解多种邻苯二甲酸酯,例如邻苯二甲酸苄基酯、邻苯二甲酸二丁酯、邻苯二甲酸二甲酯、邻苯二甲酸二辛酯和邻苯二甲酸二乙酯,DEHP均能将它们作为唯一碳源。在上述最佳降解条件下,DEHP初始浓度为200mg/L时,L1-W降解DEHP的动力学遵循一阶方程,半衰期为11.3小时,此时98.7%的DEHP被降解。根据这些发现,菌株Ochrobactrum antropi L1-W可用于从污染环境中去除DEHP,因而修复环境。

关键词：邻苯二甲酸二(2-乙基己)酯苍白杆菌生物降解鉴定邻苯二甲

回顾性比较研究急诊阑尾切除术和延迟阑尾切除术

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回顾性比较研究急诊阑尾切除术和延迟阑尾切除术

作者： Gusa jean bosco 中国医科大学

学位级别：硕士

目的:回顾性比较分析接受急诊阑尾切除术(24小时)患者的临床资料,探讨两者之间的手术效果,并发症,住院时间等的差异。研究方法:本研究回顾性分析2017年1月至2019年1月盛京医院普外二科病房入院患者的记录,并确诊为急性阑尾炎,并在出院... 详细信息

目的:回顾性比较分析接受急诊阑尾切除术(24小时)患者的临床资料,探讨两者之间的手术效果,并发症,住院时间等的差异。研究方法:本研究回顾性分析2017年1月至2019年1月盛京医院普外二科病房入院患者的记录,并确诊为急性阑尾炎,并在出院前接受阑尾切除术。诊断为慢性阑尾炎,接受非手术治疗,接受阑尾切除术合并其他手术,怀孕患者以及病理不完整或重复的患者被排除。我们将患者分为两组。那些接受紧急手术和接受延期手术的人。使用Student’s t检验进行数据分析,考虑p<0.05为有统计学意义。结果:在146例诊断为急性阑尾炎患者中,123例(84.2%)接受过急诊手术,并发症,手术时间,术后住院时间,肠功能恢复时间跟延迟手术患者无显着差异,但失血量明显增加并有统计意义(p=0.028)结论:行延迟阑尾切除术(来到医院24小时后)不明显影响手术结果和并发症。

关键词：急诊阑尾切除术延迟阑尾切除术

Optimization of Cellulose Nanocrystal Isolation from Ayous Sawdust Using Response Surface Methodology

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Journal of Materials Science and Chemical Engineering 2024年第1期12卷 36-55页

作者： Tchigo Alifa Hamida Aminatou Oumar Said jean-bosco Tchatchueng Department of Chemical Engineering School of Chemical Engineering and Mineral Industries University of Ngaoundere Ngaoundere Cameroon Department of Applied Chemistry National Advanced School of Agro-Industrial Sciences University of Ngaoundere Ngaoundere Cameroon Department in Charge of Coordination and Valorisation of Research National Advanced School of Engineering University of Yaounde 1 Yaounde Cameroon

This study focuses on the extraction of cellulose nanocrystals (CNC), from microcrystalline cellulose (MCC), derived from Ayous sawdust. The process involves multiple steps and a large amount of chemical products. The objective of this research was to determine the effects of factors that impact the isolation process and to identify the optimal conditions for CNC isolation by using the response surface methodology. The factors that varied during the process were the quantity of MCC, the concentration of sulfuric acid, the hydrolysis time and temperature, and the ultrasonic treatment time. The response measured was the yield. The study found that with 5.80 g of microcrystalline cellulose, a sulfuric acid concentration of 63.50% (w/w), a hydrolysis time of 53 minutes, a hydrolysis temperature of 69˚C, and a sonication time of 19 minutes are the ideal conditions for isolation. The experimental yield achieved was (37.84 ± 0.99) %. The main factors influencing the process were the sulfuric acid concentration, hydrolysis time and temperature, with a significant influence (p < 0.05). Infrared characterization results showed that nanocrystals were indeed isolated. With a crystallinity of 35.23 and 79.74, respectively, for Ayous wood fiber and nanocrystalline cellulose were observed by X-ray diffraction, with the formation of type II cellulose, thermodynamically more stable than native cellulose type I.

关键词： Ayous Sawdust Lignocellulosic Waste Isolation Cellulose Nanocrystals Optimization Response Surface Methodology

Reaction of Ferralsol to Acidifying Effect of Nitrogen Fertilisation

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Journal of Agricultural Chemistry and Environment 2021年第1期10卷 69-79页

作者： John Stephen Tenywa jean bosco Ngarukiyimana Alice Amoding Katushabe College of Agricultural and Environmental Sciences Makerere University Kampala Uganda

Background: The objective of this study was to determine the short-term effect of urea fertiliser application on soil reactions in a Ferralsol, with particular thrust on P sorption. Methods: Two experiments were conducted for this purpose: 1) a screenhouse pot experiment; and 2) a laboratory P sorption component. The pot (10 litre capacity plastic pots) experiment was conducted at the Makerere University Agricultural Research, Kabanyolo in Uganda, using a Ferralsol. The study comprised of four urea N (46% N) fertiliser treatments, namely, 0, 40, 80 and 120 kg N·ha-1, equivalent to 0, 200, 400 and 600 mg N per pot. A completely randomised design was adopted with three replicates. Urea rates were applied in 50% split doses, one at planting and the other at 19 days after seedling emergence (to simulate farmer practice). This was followed by watering to field capacity using distilled water. Soil samples were taken at three daily intervals until day fourteen;thereafter, soil sampling was at an interval of seven days. The second urea split dose was applied at 21 days followed by soil sampling at an interval of three days till day fourteen. Thereafter, soil was sampled at seven day intervals until the end of experiment. Soil samples were analysed for exchangeable H+, Al3+, NH4+and NO3- ions. The reaction trends of the concentrations of these ions and Bray 1 P were used to structure different response curves repres

关键词： Urea Hydrolysis Ammonification Phosphorus Sorption