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Kinetics of Sorption of Pendimethalin on Soil Samples Obtained from the Banks of Rivers Katsina-Ala and Benue, Central Nigeria

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Journal of Geoscience and Environment Protection 2016年第1期4卷 37-42页

作者： Justin Kpagh rufus Sha’Ato Raymond A. Wuana Terrumun A. Tor-Anyiin Department of Chemistry University of Agriculture Makurdi Nigeria

Kinetics of the sorption of the herbicide, pendimethalin (3,4-Dimethyl-2,6-dinitro-N-pentan-3-yl-aniline) on four soil samples obtained from the banks of Rivers Benue and Katsina-Ala, in Central Nigeria was studied by contacting 5.0 g soil samples with 100 mL 7 × 10-6 M herbicide solution. The sorption was monitored by following the herbicide concentration in the aqueous phase spectrophotometrically at one hour intervals for 5 hours (at 25°C, 35°C, 45°C, 55°C and 65°C, respectively). Pseudo-first order kinetics treatment of the data showed that sorption rates as well as the accompanying activation energies were low, indicating that physical adsorption is the operative mechanism for its retention in the soils and that the herbicide tended to reside more in the aqueous phase, which raised its potential to contaminate natural water systems, when applied on the field.

关键词： Kinetics Sorption Pendimethalin Soil Nigeria

Characterisation of Meteorological Drought in Northern Nigeria Using Comparative Rainfall-Based Drought Metrics

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Journal of Water Resource and Protection 2023年第2期15卷 51-70页

作者： Onemayin David Jimoh Martins Yusuf Otache Adeolu Richard Adesiji rotimi Saka Olaleye James Agajo Department of Civil Engineering Federal University of Technology Minna Nigeria Department of Agricultural & Bioresources Engineering Federal University of Technology Minna Nigeria Department of Agricultural Economics & Farm Management Federal University of Technology Minna Nigeria Department of Computer Engineering Federal University of Technology Minna Nigeria

Meteorological droughts occur when there is deficiency in rainfall;i.e. rainfall availability is below some acclaimed normal values. Hence, the greater challenge is to be able to obtain suitable methods for assessing drought occurrence, its onset or initiation and termination. Thus, an attempt was made in this paper to evaluate the performance of Standardised Precipitation Index (SPI) and Standardised Precipitation Anomaly Index (SPAI) to characterise drought in Northern Nigeria for purposes of comparison and eventual adoption of probable candidate index for the development of an Early Warning System. The findings indicated that despite the fact that the annual timescale may be long, it can be employed to obtain information on the temporal evolution of drought especially, regional behaviour. However, monthly timescale can be more appropriate if emphasis is on evaluating the effects of drought in situations relating to water supply, agriculture and groundwater abstractions. The SPAI can be employed for periodic rainfall time series though;it accentuates drought signatures and may not necessarily dampen high fluctuations due to implications of high climatic variability considering the stochastic nature and state transition of drought phenomena. On the other hand, the temporal evolution of SPI and SPAI were not coherent at different temporal accumulations with differences in fluctuations. However, despite the differences between the SPI and SPAI, generally at some timescales, for instance, 6-month accumulation, both spatial and temporal distributions of drought characteristics were seemingly consistent. In view of the observed shortcomings of both indices, especially the SPI, the Standardised Nonstationary Precipitation Index (SnsPI) should be looked into and too, other indexes that take into consideration the implications of global warming by incorporating potential evapotranspiration may be deemed more suitable for drought studies in Northern Nigeria.

关键词： Characterisation Timescale Meteorological Drought Metrics

On Vehicle Routing Problems (VRP) with a Focus on Multiple Priorities

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American Journal of Computational Mathematics 2019年第4期9卷 348-357页

作者： Kayode J. Adebayo Felix M. Aderibigbe Adejoke O. Dele-rotimi Department of Mathematics Ekiti State University Ado Ekiti Nigeria College of Education Ikere Ekiti Nigeria

This paper discusses the concept of priorities based on Time and Quantity, which arise on the occasion of vehicle routing. It explains the interconnectivity between the priorities based on Time and Quantity and formulates a dynamic that shows the fusion of Time and Quantity into the Vehicle Routing Problem’s objective function. The paper focuses on the development of an expanded VRP objective function in which the priorities based on Time and Quantities are imbedded thus opens a vista of knowledge, aggregating and modelling the priorities as a mean to reduce transportation costs that lead to an organized and more timely deliveries of goods employing various of today’s proposed logistic systems coupled with widely used positioning systems.

关键词： Vehicle Routing Problems Time Window Quantity Priority

Development of a Best Answer Recommendation Model in a Community Question Answering (CQA) System

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Intelligent Information Management 2021年第3期13卷 180-198页

作者： rotimi Olaosebikan Akintoba Emmanuel Akinwonmi Bolanle Adefowoke Ojokoh Oladunni Abosede Daramola Oladele Stephen Adeola Department of Information and Communication Technology Adekunle Ajasin University Akungba-Akoko Nigeria Department of Computer Science Federal University of Technology Akure Nigeria Department of Information Systems Federal University of Technology Akure Nigeria Department of Information Technology Federal University of Technology Akure Nigeria

In this work, a best answer recommendation model is proposed for a Question Answering (QA) system. A Community Question Answering System was subsequently developed based on the model. The system applies Brouwer Fixed Point Theorem to prove the existence of the desired voter scoring function and Normalized Google Distance (NGD) to show closeness between words before an answer is suggested to users. Answers are ranked according to their Fixed-Point Score (FPS) for each question. Thereafter, the highest scored answer is chosen as the FPS Best Answer (BA). For each question asked by user, the system applies NGD to check if similar or related questions with the best answer had been asked and stored in the database. When similar or related questions with the best answer are not found in the database, Brouwer Fixed point is used to calculate the best answer from the pool of answers on a question then the best answer is stored in the NGD data-table for recommendation purpose. The system was implemented using PHP scripting language, MySQL for database management, JQuery, and Apache. The system was evaluated using standard metrics: Reciprocal Rank, Mean Reciprocal Rank (MRR) and Discounted Cumulative Gain (DCG). The system eliminated longer waiting time faced by askers in a community question answering system. The developed system can be used for research and learning purposes.

关键词： Question Answer Recommendation Fixed Point Theorem Classification Retrieval Fixed-Point Score Reciprocal Rank Discounted Cumulative Gain

Variability and Trends of Daily Heavy Rainfall Events over Niger River Basin Development Authority Area in Nigeria

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American Journal of Climate Change 2014年第1期3卷 1-7页

作者： Joseph Sunday Babatolu rufus Temidayo Akinnubi Akintade Taiwo Folagimi Omosuyi Oluwayemisi Bukola Department of Agricultural Science Adeyemi College of Education Ondo Nigeria Department of Geography Adeyemi College of Education Ondo Nigeria Department of Physics Adeyemi College of Education Ondo Nigeria

Using 70 years of daily rainfall records in eight stations, an analysis of variability and trends of daily heavy rainfall events over Niger River Basin Development Authority Area was carried out by using Standardized Anomaly Index and Spearman Rank Correlation Coefficient. Significant temporal variability on interannual and decadal time-scales was observed in the frequency of heavy rainfall events and annual heavy rainfall amount. Both the annual heavy rainfall amount and frequency of heavy rainfall events demonstrated no pronounced temporal decreasing or increasing trend. However, more recent data records from 1981 onwards revealed an increasing trend. Thus, evidence of a temporal change is apparent in heavy rainfall events in the last three decades in sympathy with global warming.

关键词： Rainfall Anomalies River Niger Basin Development Authority Area

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宁波智慧地铁的商业模式研究

宁波智慧地铁的商业模式研究

作者：陈敏（rufus Chen）宁波大学

学位级别：硕士

宁波智慧地铁是通过互联网思维布局轨道交通并构建“互联网+地铁”探索模式的新型代表。该项目以提供交通信息的公共服务为切入点,通过“宁波地铁”手机应用为基础的互联网平台,整合宁波轨道交通线网的广告资源、商铺资源,并利用庞大的... 详细信息

宁波智慧地铁是通过互联网思维布局轨道交通并构建“互联网+地铁”探索模式的新型代表。该项目以提供交通信息的公共服务为切入点,通过“宁波地铁”手机应用为基础的互联网平台,整合宁波轨道交通线网的广告资源、商铺资源,并利用庞大的乘客乘车数据和顾客消费数据实现精准营销,从而打造本地生活入口及同城电商平台,最终实现“乘客变顾客、站点变社区”的商业模式创新。论文立足于商业模式的理论研究,从客户价值主张、盈利模式、关键资源、关键流程四个核心构成要素,阐述了传统地铁商业模式的发展现状和无法弥补巨额运营亏损的核心难题。与此同时,从区域环境和行业环境多个维度分析了宁波智慧地铁可行性,并对其商业模式的四要素和价值链的创新之处进行了评估,后又在此基础上对宁波智慧地铁商业模式的运营难点及保障措施进行分析,并最终对四要素优化后的商业模式所带来的经济效益和社会效益进行展望与总结,以期为宁波智慧地铁的商业模式的构建、创新、发展提供参考。

关键词：智慧地铁互联网商业模式创新

GIS Mapping, Biomonitoring and Distribution of Heavy Metal Concentrations Using Neem (Azadirachta indica) Bark in Makurdi Town, Benue State, Nigeria

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Journal of Geoscience and Environment Protection 2023年第7期11卷 213-226页

作者： Ada Florence Ogli Mohammed Ahmed Adams Udoji Itodo Raymond Ahulle Wuana rufus Sha’Ato Department of Chemistry Akawe Torkula Polytechnic Makurdi Nigeria Department of Geography Bayero University Kano Nigeria Department of Chemistry/Centre for Agrochemical Technology Joseph Sarwuan Tarka University Makurdi Nigeria

The present work determined the concentration and spatial distribution of heavy metals (As, Hg, Cr, Cd and Pb) in soil samples from Makurdi and its environs using geographic information system (GIS). The specific objective is to produce the spatial distribution maps showing the spatial distribution of toxic heavy metals in the study area. Inverse Distance Weighting (IDW), a GIS technique was used to produce dotted maps showing the spatial distribution of heavy metals in neem bark for better visualization of contamination zones and non-contamination zones. The map reveals few hotspot areas showing areas of high concentrations of the heavy metals investigated which were identified in red colours, the following concentration ranges were obtained;As (4.71 - 6.43 mg/kg), Cd (13.9 - 16.84 mg/kg), Cr (46.3 - 60.84 mg/kg), Hg (3.70 - 5.05 mg/kg) and Pb (24.02 - 31.34 mg/kg). These hotspot areas were found close to business outlets, fuel filling and service stations, farm sites where the application of fertilizers and pesticides were persistent coupled with heavy traffic of vehicles and other machinery which was associated with As, Hg, Cd, Pb and Cr been released into the environment thus, suggesting anthropogenic activities controlling the concentration of these heavy metals in the study areas. The cumulative effect of these heavy metals into the barks of neem could pose as danger, because this plant is used as herbs in folk medicine.

关键词： Heavy Metal Contamination Spatial Distribution Inverse Distance Weighting Folk Medicine Makurdi

Modeling and Simulation of Hydrogen Storage Device for Fuel Cell Plant

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Journal of Chemistry and Chemical Engineering 2012年第7期6卷 604-612页

作者： Akanji Olaitan Lukman Obadele Babatunde Abiodun Oluranti Sadiku-Agboola Patricia Abimbola Popoola Emmanuel rotimi Sadiku Department of Chemical & Metallurgical Engineering Faculty of Engineering and The Built Environment Tshwane University of Technology Pretoria West 0001 Pretoria South Africa Department of Mechanical Engineering Faculty of Engineering and Built Environment Tshwane University of Technology Lynrrwoodridge 0001 South Africa

The article reviews a brief literature on the modeling of hydrogen storage device for fuel cell. Different dimensional approaches in modeling hydrogen absorption/desorption in a metal hydride reactor for use in fuel cell are summarized. Mathematical modeling equations involved are also stated. The effect of various operating parameters such as temperature, concentration, viscosity, thermal conductivity and time on the gas is also verified. The importance of various simulation software with reference to their major functions is also identified. The review concludes on the opportunities and challenges with the use of hydrogen as an alternative renewable energy.

关键词： Modeling simulation hydrogen storage fuel cell.

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影响“爱爱”因素

健康管理 2012年第5期 61-62页

作者： Anneli rufus

一做爱,除了跟谁做之外,季节、时间、温度、天气,甚至就业状况和今天星期几都是可能影响人们做爱与否的因素。从气候变化,昼夜交替,到雨过天晴与工作日和休假的转换,都会微妙地影响人们的身体和心理。在性方面也是如此,当统计了足够多... 详细信息

一做爱,除了跟谁做之外,季节、时间、温度、天气,甚至就业状况和今天星期几都是可能影响人们做爱与否的因素。从气候变化,昼夜交替,到雨过天晴与工作日和休假的转换,都会微妙地影响人们的身体和心理。在性方面也是如此,当统计了足够多的人群,就会发现人们做爱的频率与前边说的那些变化有一定的关系。

关键词：销量月份