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Urbanization and Flood Risk： Implication for Coping in Coastal Zones of Nigeria

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Sociology Study 2013年第11期3卷 889-896页

作者： Agnes Philip-Ogoh David Babatunde akinola Regina Umana Udontia FCT College of Education Zuba-Abuja Nigeria University of Abuja Nigeria Local Education Authority Abuja Nigeria

This study looked at rapid urbanization and the flood risk it portends with a view to identifying mechanisms for coping in coastal zones of Nigeria. Flooding is one of the various ecological problems that has taken its toll on the quality of the environment, human health, and economic growth in parts of Africa and the coastal zones of Nigeria in particular. Rapid urbanization has been seen to result in changes in land use patterns which can adversely affect the hydrological processes in a catchment leading to a deteriorating water environment. warning systems are identified and discussed in the paper Structural and non-structural approach as well as flood early as flood risks coping mechanisms, It also discusses the policy implications that government through its relevant agencies must be up to its game by monitoring precursors, forecasting of probable floods and notification of alerts, It concludes and recommends that an active involvement of communities at risks is required and public education and awareness of risks should be facilitated through effective dissemination, as well as ensuring that there is a constant preparedness,

关键词： Urbanization flooding flood risk coastal zones coping

Distributed Majorization-Minimization for Laplacian Regularized Problems

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IEEE/CAA Journal of Automatica Sinica 2019年第1期6卷 45-52页

作者： Jonathan Tuck David Hallac stephen Boyd IEEE the Department of Electrical Engineering Stanford University

We consider the problem of minimizing a block separable convex function(possibly nondifferentiable, and including constraints) plus Laplacian regularization, a problem that arises in applications including model fitting, regularizing stratified models, and multi-period portfolio optimization. We develop a distributed majorization-minimization method for this general problem, and derive a complete, self-contained, general,and simple proof of convergence. Our method is able to scale to very large problems, and we illustrate our approach on two applications, demonstrating its scalability and accuracy.

关键词： Convex optimization distributed optimization graphical networks Laplacian regularization

Power plant selection in a carbon constrained world the TERA(technoeconomic environmental risk analysis)

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航空动力学报 2009年第4期24卷 896-902页

作者： stephen Ogaji Pericles Pilidis Vishal Sethi Department of Power and Propulsion School of Engineering Cranfield University

There is an increasing concern that current trends of consumption of natural resources cannot *** is imperative that major targeted investments are made into economical and reliable environment friendly propulsion and power *** novel and promising concepts are being *** selection of the best candidates to pursue for investment becomes a very difficult choice.A detailed TERA(techno-economic environmental risk analysis) framework is described here to quantify risks and to compare and rank competing schemes on a formal and consistent *** technique is based on detailed and rigorous thermodynamic representations of power plants.A layer of environment,economic,weather and other models to describe the appropriate local conditions is superimposed to *** outcome is a techno-economic environmental risk analysis framework with appropriate detail of each power plant as applied to the appropriate *** results for each concept can then be compared and contrasted to make appropriate selections.

关键词： TERA(techno-economic environmental risk analysis) techno-economic risk analysis gas turbine multi-disciplinary optimisation(MDO)

Design and Modeling of S Band Circular Patch and Ka Band Horn Antenna, Integration with Future Multifunctional Radio over Fiber Network

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Open Journal of Antennas and Propagation 2017年第3期5卷 121-131页

作者： Rao Kashif oluwole John Famoriji Fujiang Lin Department of Electronic Science and Technology University of Science and Technology of China Anhui China

Radio over Fiber is an integration of microwave and optical fiber technologies having numerous benefits. RoF technology can give a scope of advantages including the capacity for backing multiple radio services and standards. In coming future, there is need of integrated wireless service with high speed satellite broadband and multifunctional indoor/outdoor antennas. Radio over fiber is one of the most favorite candidates to meet all these requirements of future multifunctional integrated wireless communication. Due to planer profile, small size and low cost patch antennas are most favorite to use for multi- frequency applications. In this paper, we present system level design for future multifunctional radio over fiber network. Under FTTH (Fiber To The Home) technology, it will be possible to use multi-frequency applications on single fiber medium. Firstly, we designed S band circular patch antenna (2.5 GHz) and Ka band (29 GHz) horn antenna. Circular patch antenna performance is estimated with different substrate height. After getting S parameters and far-field results, we did modeling of Radio over Fiber system over (10 Km) with same parameters from antenna results.

关键词： Radio over Fiber S-Band Ka-Band March Zehnder Modulator CW Laser

Epidemiological Pattern of Lassa Fever Outbreak in Ondo State, Southwest Nigeria, 2014 to 2019

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Open Journal of Epidemiology 2021年第1期11卷 92-100页

作者： Elvis Efe Isere Temioluwa Fuwape Gboyega Adekunle Famokun stephen Fagbemi akinola Ayoola Fatiregun Nosa Eniye Omorogbe Adewale Moses Adejugbagbe Temitope Olajumoke Omoju Department of Epidemiology and Medical Statistics University of Ibadan Ibadan Nigeria George Mason University Virginia USA Nigeria Field Epidemiology and Laboratory Training Programme Abuja Nigeria Ondo State Ministry of Health Akure Nigeria World Health Organization Ondo State Field Office Akure Nigeria Medical Laboratory Science Council of Nigeria Abuja Nigeria

Introduction: Annual outbreak of Lassa Fever (LF) has been reported in Ondo State over the years. We analyzed LF surveillance data from January 2014 to December 2019 to describe the epidemiological pattern of the outbreak. Method: Lassa fever dataset from January 2014 to December 2019 was obtained from the State Ministry of Health. Variables analyzed include date of onset of symptom, age, gender, place (Local Government Area, LGA) and outcome of laboratory test. Data were summarized using frequencies, proportions, chart and maps. Results: From January 2014 and December 2019, 2141 suspected LF cases were reported. Of these, 551 cases were laboratory confirmed with 134 deaths recorded. The LF cases (suspected vs. confirmed) reported increased in 2016 (73 vs. 19), 2017 (207 vs. 76), 2018 (452 vs. 159) and 2019 (856 vs. 285) respectively. Most of the confirmed cases (89.5%) were ≥15 years while more than half (53.7%) were males. Prior to 2016, only two LGAs (Owo and Ose) recorded continued transmission of the disease. However, between 2016 and 2019, the disease had spread to 8 neighboring LGAs (P < 0.001) with the CFR declining from 67% in 2015 to 20% in 2019. Conclusion: We found an unusual increase in the suspected LF cases reported between January 2016 and December 2019 with a corresponding increase in the confirmed cases and high annual case fatality rates. Hence, we recommend intensified surveillance activities to enhance timely reporting of cases and laboratory confirmation to ensure early commencement of treatment to reduce the case fatality rate.

关键词： Lassa Fever Outbreak Epidemiological Pattern Ondo State

Influence of Non-Natural Ageing Temperature on the Microstructural Characteristics and Mechanical Properties of Cast Aluminum 6063 Alloy

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Journal of Minerals and Materials Characterization and Engineering 2024年第2期12卷 91-99页

作者： oluwole Oladele Ayodele Adedeke Olajesu Olanrewaju Samuel Olusunle Department of Metallurgical and Materials Engineering Federal University of Technology Akure Ondo State Nigeria Engineering Materials Development Institute NASENI Akure Ondo State Nigeria Department of Materials Science and Engineering Iowa State University Ames IA USA NASENI Abuja Nigeria

This research considered the effect of non-natural aging on the microstructural characteristics and mechanical properties of as-cast aluminum 6063 alloys. The samples were developed through a sand casting process and machined into tensile and impact test samples before carrying out solution heat treatment at 550?C (0.83 Tm) on two parts of the samples while retaining one part as the control. The two parts were further divided into sets denoted A and B and were aged at 180?C (0.27 Tm) and 160?C (0.24 Tm), respectively, for 12 hours. The results showed that sample A has the optimal yield strength and ultimate tensile strength of 192 and 206 MPa, respectively. Likewise, the sample gave the highest impact strength value of about 9.63 J/mm2. The observed results were supported by the optical micrograph, which revealed that the sample has evenly dispersed precipitates in its microstructure. This is deemed responsible for the observed increase in strength of the sample.

关键词： Aluminum Alloy Non-Natural Ageing Mechanical Properties Microstructural Features

Influence of Degree of Cold-Drawing on the Mechanical Properties of Low Carbon Steel

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Materials Sciences and Applications 2011年第11期2卷 1556-1563页

作者： Nurudeen A. Raji Oluleke O. oluwole 不详

Low carbon steel metal is used for the manufacture of nails. Steel wire with <0.3% C content is cold-drawn through a series of drawing dies to reduce the diameter of the wire to the required diameter of the nails. A 0.12%w C steel wire cold drawn progressively by 20%, 25%, 40% and 50% was investigated. The influence of the degree of cold drawing on the mechanical properties of the carbon steel material were studied using the tensile test, impact test and hardness test experiments in order to replicate the service condition of the nails. The tensile test was done on a Montanso? tensometer to investigate the yield strength and the tensile strength of the material as the degree of deformation increases. An Izod test was used to determine the impact toughness of the steel using the Hounsfield impact machine and the hardness numbers were obtained for the different degrees of drawn deformation of the steel on the Brinnel tester. The study used the stress-strain relationship of the tensile test experiment to study the effect of the degree of cold-drawing deformation on the yield strength and tensile strength properties of the low carbon steel. The yield strength of the material was observed to reduce with increasing degree of cold-drawing, an indication of reduction in the ductility and the tensile strength of the material reduced with increasing degree of cold-drawn deformation. The ability of the material to resist impact loads when nails are hammered reduced with increasing degree of drawn deformation as a result of strain hardening of the material after the drawing operation. However the resilience of the material to further cold drawn deformation increased with increasing degree of deformation as evident in the Brinnel hardness number which increases with the degree of drawing deformation. This is an indication of the material’s approach to brittleness as the degree of drawn deformation increases.

关键词： Cold-Drawn Deformation Stress-Strain Toughness Yield Strength Tensile Strength

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快速公交电子支付的接受度：挑战与前瞻

快速公交电子支付的接受度：挑战与前瞻

作者： Alademomi Richard oluwole 中国科学技术大学

学位级别：硕士

尽管电子支付系统已经引起了全球各地学者的兴趣,事实上,考虑到其操作易用性和实用性,电子支付系统在全球使用者范围内的接受度不高。许多学者认为信任是影响人类决定接受的重要因素,到目前为止,对信任在电子支付系统中的地位的研究屈... 详细信息

尽管电子支付系统已经引起了全球各地学者的兴趣,事实上,考虑到其操作易用性和实用性,电子支付系统在全球使用者范围内的接受度不高。许多学者认为信任是影响人类决定接受的重要因素,到目前为止,对信任在电子支付系统中的地位的研究屈指可数。在快速公共交通中引入电子支付系统,这一系统得到了进一步发展,并成为拉各斯州家喻户晓的名称之一。目前拉各斯快速公共交通的付款规定水平不足以与其他使用快速公共交通的发展中国家(如中国)相比。目前,它在满足用户需求方面是不充分和低效的,由于对支付系统缺乏信任,目前的支付策略(电子支付)仅限于少数用户。在快速公交交易中,超过85%的日常支付是通过旧的支付方式完成的。本研究主要探讨信任在影响拉各斯快速公共交通系统电子支付接受度中的中介作用;信任作为一个独特的技术来衡量在支付系统中用户对电子支付设备的接受程度及其对电子支付设备接受程度的直接影响。这是通过使用三个灵活且适当的指标(感知安全性、感知实用性和感知易用性)来实现的,这些指标曾被各种学者用于确定是否接受创新技术。通过对Buckley等人201 8年提出的计划行为理论和技术接受模型(TAM)的描述,我们用一组为期365份研究数据证实了信任作为中介变量的有效性,并通过结构方程模型(LISREL)验证了该假设的有效性和可靠性。另一方面,该效应强烈支持感知易用性和感知安全性的效应,感知实用性未在最终结果中找到支持。最重要的是,信任对电子支付系统的接受度有显著的影响。研究结果为提高快速公共交通用户对于电子支付系统的接受度提供了积极的方法。本研究采用量化技术解读原始资料,并对不同路线的不同使用者进行了全面的问卷调查,以搜集研究结果所需的足够的和基本的资料信息。研究发现,大多数参与本研究的用户更倾向于使用电子方式支付,而不是实物现金支付。与此同时,那些对电子设备所提供的服务质量特别满意的用户,相对于旧的支付系统,他们更加信任电子设备。与这一结果相关的是,预计信任作为中介促进了用户的满意度并使得用户对设备的接受度有所提高,所有结果都可以追溯到以前与电子支付研究有关的文献。此外,本研究通过将三个弹性指标应用于确切案例,并检查来自大都市内不同路线的400名使用者当中的356人所产生的广泛结果,验证了本论文的首要目标。结果意外地反映出实用性的负面影响,因为大多数用户不相信在实用性方面的信任会使得他们接受设备。尽管该设备是有用的,方便的,安全的且易于使用的,一般的用户似乎不接受用这个设备付款。拉各斯州政府和管理层有必要深入研究可接受性方面的不足,而不是更多地追求电子支付方式的利润最大化,他们应该深入研究这个问题,并提出有效的解决方案,以缓解潜在用户在支付过程中所遇到的压力。

关键词：结构方程模型技术接受模型快速公共交通信任电子货币

Radio over Fiber System Level Performance Analysis, Maintaining Signal Integrity

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Journal of Computer and Communications 2017年第13期5卷 1-8页

作者： Rao Kashif oluwole John Famoriji Fujiang Lin Department of Electronic Engineering and Communication University of Science and Technology Hefei China

Radio over fiber is an integration of microwave and optical fiber technologies having numerous benefits. RoF technology can give a scope of advantages including the capacity for backing multiple radio services and standards. In order to maintain Signal Integrity in RoF system, it’s indispensable to take all components of a system under rooted consideration. Due to the increasing number of RoF application, it’s necessary to do some system level changes in designing RoF transceiver. In this paper we compared two popular modulation techniques NRZ (non return to zero) and RZ (return to zero) for better signal integrity in RoF system. Secondly we also did analysis of RoF transceiver with APD and PIN photo detectors and compared the performance on different distances. Hence the Q factor of PIN and APD photo diodes and comparison of NRZ and RZ modulation will be helpful for system designers who are working on better signal Integrity in Radio over fiber systems.

关键词： RoF PIN APD NRZ RZ & Photodiode