Search results for: reclamation area
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8945

Search results for: reclamation area

7205 Geochemical Characterization of the Fahdene Formation in the Kef-Tedjerouine Area (Northwestern Tunisia)

Authors: Tahani Hallek, Dhaou Akrout, Riadh Ahmadi, Mabrouk Montacer

Abstract:

The present work is an organo-geochemical study of the Fahdene Formation outcrops at the Mahjouba region belonging to the Eastern part of the Kalaat Senan structure in northwestern Tunisia (the Kef-Tedjerouine area). The analytical study of the organic content of the samples collected, allowed us to point out that the Formation in question is characterized by an average to good oil potential. This fossilized organic matter has a planktonic marine origin (type II), as indicated by the relatively high values of hydrogen index. Tmax values are in the range 440°C and attest a thermal stage of the oil window beginning. Mineralogical study found the existence of macro and micro fractures that are parallel to rock stratification or oblique with a high density. Fill standpoint, the major component of the mineralized veins is the fibrous calcite with bitumen traces. The composition of these fractures is mainly due to the availability of chemical elements scattered in the surrounding rock. As for the origin of these fractures, we assume that fluid pressure processes are heavily involved, together with the regional compressional tectonic stress regime. The Fahdene Formation has a great importance in conventional oil development as a potential source rock, and even in terms of unconventional oil exploitation through the intense fracturing allowing the percolation of gas shale and facilitating its exploitation.

Keywords: fluid pressure, fracturation, oil exploration, organic matter

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7204 The Use of a Rabbit Model to Evaluate the Influence of Age on Excision Wound Healing

Authors: S. Bilal, S. A. Bhat, I. Hussain, J. D. Parrah, S. P. Ahmad, M. R. Mir

Abstract:

Background: The wound healing involves a highly coordinated cascade of cellular and immunological response over a period including coagulation, inflammation, granulation tissue formation, epithelialization, collagen synthesis and tissue remodeling. Wounds in aged heal more slowly than those in younger, mainly because of comorbidities that occur as one age. The present study is about the influence of age on wound healing. 1x1cm^2 (100 mm) wounds were created on the back of the animal. The animals were divided into two groups; one group had animals in the age group of 3-9 months while another group had animals in the age group of 15-21 months. Materials and Methods: 24 clinically healthy rabbits in the age group of 3-21 months were used as experimental animals and divided into two groups viz A and B. All experimental parameters, i.e., Excision wound model, Measurement of wound area, Protein extraction and estimation, Protein extraction and estimation and DNA extraction and estimation were done by standard methods. Results: The parameters studied were wound contraction, hydroxyproline, glucosamine, protein, and DNA. A significant increase (p<0.005) in the hydroxyproline, glucosamine, protein and DNA and a significant decrease in wound area (p<0.005) was observed in the age group of 3-9 months when compared to animals of an age group of 15-21 months. Wound contraction together with hydroxyproline, glucosamine, protein and DNA estimations suggest that advanced age results in retarded wound healing. Conclusion: The decrease wound contraction and accumulation of hydroxyproline, glucosamine, protein and DNA in group B animals may be associated with the reduction or delay in growth factors because of the advancing age.

Keywords: age, wound healing, excision wound, hydroxyproline, glucosamine

Procedia PDF Downloads 658
7203 Allometric Models for Biomass Estimation in Savanna Woodland Area, Niger State, Nigeria

Authors: Abdullahi Jibrin, Aishetu Abdulkadir

Abstract:

The development of allometric models is crucial to accurate forest biomass/carbon stock assessment. The aim of this study was to develop a set of biomass prediction models that will enable the determination of total tree aboveground biomass for savannah woodland area in Niger State, Nigeria. Based on the data collected through biometric measurements of 1816 trees and destructive sampling of 36 trees, five species specific and one site specific models were developed. The sample size was distributed equally between the five most dominant species in the study site (Vitellaria paradoxa, Irvingia gabonensis, Parkia biglobosa, Anogeissus leiocarpus, Pterocarpus erinaceous). Firstly, the equations were developed for five individual species. Secondly these five species were mixed and were used to develop an allometric equation of mixed species. Overall, there was a strong positive relationship between total tree biomass and the stem diameter. The coefficient of determination (R2 values) ranging from 0.93 to 0.99 P < 0.001 were realised for the models; with considerable low standard error of the estimates (SEE) which confirms that the total tree above ground biomass has a significant relationship with the dbh. The F-test value for the biomass prediction models were also significant at p < 0.001 which indicates that the biomass prediction models are valid. This study recommends that for improved biomass estimates in the study site, the site specific biomass models should preferably be used instead of using generic models.

Keywords: allometriy, biomass, carbon stock , model, regression equation, woodland, inventory

Procedia PDF Downloads 446
7202 Development of Three-Dimensional Groundwater Model for Al-Corridor Well Field, Amman–Zarqa Basin

Authors: Moayyad Shawaqfah, Ibtehal Alqdah, Amjad Adaileh

Abstract:

Coridoor area (400 km2) lies to the north – east of Amman (60 km). It lies between 285-305 E longitude and 165-185 N latitude (according to Palestine Grid). It been subjected to exploitation of groundwater from new eleven wells since the 1999 with a total discharge of 11 MCM in addition to the previous discharge rate from the well field 14.7 MCM. Consequently, the aquifer balance is disturbed and a major decline in water level. Therefore, suitable groundwater resources management is required to overcome the problems of over pumping and its effect on groundwater quality. Three–dimensional groundwater flow model Processing Modeflow for Windows Pro (PMWIN PRO, 2003) has been used in order to calculate the groundwater budget, aquifer characteristics, and to predict the aquifer response under different stresses for the next 20 years (2035). The model was calibrated for steady state conditions by trial and error calibration. The calibration was performed by matching observed and calculated initial heads for year 2001. Drawdown data for period 2001-2010 were used to calibrate transient model by matching calculated with observed one, after that, the transient model was validated by using the drawdown data for the period 2011-2014. The hydraulic conductivities of the Basalt- A7/B2 aquifer System are ranging between 1.0 and 8.0 m/day. The low conductivity value was found at the north-west and south-western parts of the study area, the high conductivity value was found at north-western corner of the study area and the average storage coefficient is about 0.025. The water balance for the Basalt and B2/A7 formation at steady state condition with a discrepancy of 0.003%. The major inflows come from Jebal Al Arab through the basalt and through the limestone aquifer (B2/A7 12.28 MCMY aquifer and from excess rainfall is about 0.68 MCM/a. While the major outflows from the Basalt-B2/A7 aquifer system are toward Azraq basin with about 5.03 MCMY and leakage to A1/6 aquitard with 7.89 MCMY. Four scenarios have been performed to predict aquifer system responses under different conditions. Scenario no.2 was found to be the best one which indicates that the reduction the abstraction rates by 50% of current withdrawal rate (25.08 MCMY) to 12.54 MCMY. The maximum drawdowns were decreased to reach about, 7.67 and 8.38m in the years 2025 and 2035 respectively.

Keywords: Amman/Zarqa Basin, Jordan, groundwater management, groundwater modeling, modflow

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7201 Effect of Different Chemical Concentrations on Control of Dodder (Cuscuta campestris Yunck.) in Vitex (Agnus castus)

Authors: Aliyu B. Mustapha, Poul A. Gida

Abstract:

Pot experiment was conducted at the landscape unit of Modibbo Adama University of Technology, Yola in 2015 and 2016 to determine the effect of some chemicals namely glyphosate, salt and detergent on Golden dodder (Cuscuta campestris Yunk). The experiment was laid in a completely randomized design (CRD) with three replications. The treatments include the following: glyphosate-T0= (control),(Og a.i/ha-1) T1=35g a.i/ha-1, T2=70g a.i/ha-1, T3=105g a.i/ha-1, T4=140 a.i/ha-1 and T5=175g a.i/ha-1: Salt (T0=control O mole/ha-1 T1=1mole/ha-1 T2=2mole/ha-1, T3=3mole/ha-1 , T4=4mole/ha-1 and T5=5mole/ha-1:washing detergent T0=Og/ha-1(control), T1=30ml detergent +70ml distilled water T2=45ml detergent+65ml distilled water T3=60ml detergent+40ml distilled water, T4=75ml detergent+25ml distilled water and T5=90ml detergent +10mldistilled water, the treatments were replicated three times. Data were collected include: plant height, number of leaves, leaf area, leaf area index and Cuscuta cover score at 3,6,9and 12 weeks after sprouting(WAS). Biomas of Vitex was also collected at the end of the experiment. Data collected were analyzed using software Genstat version 8.0. Results showed that glyphosate gave the least Cuscuta cover score and the tallest Vitex plant. However, detergent mildly controlled Cuscuta, while salt has no effect on Cuscuta campestris indicating that glyphosate could be used in the control of parasitic dodder (Cuscuta campestris) on Vitex plant.

Keywords: chemical, control, dudder, Vitex

Procedia PDF Downloads 187
7200 Preliminary Study of Sponge Spicule to Understand Paleobathymetry, Sentolo Formation, Kulon Progo, Daerah Istimewa Yogyakarta

Authors: Akmaluddin, Aulia Agus Patria, Adniwan Shubhi Banuzaki, Lucia Hardiana Kurnia Pratiwi

Abstract:

The phylum Porifera, commonly known as sponges, is a group of primitive animals living since Paleozoic-recent, currently have over 8300 described species, where the majority lives in the marine environment and sessile or in situ. Sponge spicule is one part of the body that secreted by sponge; this spicule can be well preserved because it composed of silicate material. Sponge spicule was identified based on morphological form, which was classified into two main classes, Megasclere and Microsclere. Any form of spicule morphology will indicate a particular sponge species, and it also related to the sponge living environment. Therefore, understanding the paleobathymetry using spicules can be done and more detailed because of sponge living in situ. The methods used in this paper are stratigraphic measurement, continuous sampling, and sieve preparation to dissolve calcareous and siliciclastics materials. Then, each spicule was picked by picking method for every 100 grams of each sample and identified the morphological form to determine the order and abundance of spicule. 10 samples have analyzed, 1489 spicules were identified, there were two classes of Porifera, Demospongiae, and Hexactinellida. Five orders of Porifera also identified in the research area, Haplosclerida, Hadromerida, Agelasida, Lithistids, and Lyssacinosida. The results from descriptive analysis and spicule abundance can be understood that the paleobathymetry of research area was in intertidal zone. Furthermore, the variation and abundance of sponge spicule can be used to understand the paleobathymetry and depositional environment.

Keywords: paleobathymetry, Sentolo formation, sponge, spicule

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7199 Study on Changes of Land Use impacting the Process of Urbanization, by Using Landsat Data in African Regions: A Case Study in Kigali, Rwanda

Authors: Delphine Mukaneza, Lin Qiao, Wang Pengxin, Li Yan, Chen Yingyi

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Human activities on land use make the land-cover gradually change or transit. In this study, we examined the use of Landsat TM data to detect the land use change of Kigali between 1987 and 2009 using remote sensing techniques and analysis of data using ENVI and ArcGIS, a GIS software. Six different categories of land use were distinguished: bare soil, built up land, wetland, water, vegetation, and others. With remote sensing techniques, we analyzed land use data in 1987, 1999 and 2009, changed areas were found and a dynamic situation of land use in Kigali city was found during the 22 years studied. According to relevant Landsat data, the research focused on land use change in accordance with the role of remote sensing in the process of urbanization. The result of the work has shown the rapid increase of built up land between 1987 and 1999 and a big decrease of vegetation caused by the rebuild of the city after the 1994 genocide, while in the period of 1999 to 2009 there was a reduction in built up land and vegetation, after the authority of Kigali city established, a Master Plan where all constructions which were not in the range of the master Plan were destroyed. Rwanda's capital, Kigali City, through the expansion of the urban area, it is increasing the internal employment rate and attracts business investors and the service sector to improve their economy, which will increase the population growth and provide a better life. The overall planning of the city of Kigali considers the environment, land use, infrastructure, cultural and socio-economic factors, the economic development and population forecast, urban development, and constraints specification. To achieve the above purpose, the Government has set for the overall planning of city Kigali, different stages of the detailed description of the design, strategy and action plan that would guide Kigali planners and members of the public in the future to have more detailed regional plans and practical measures. Thus, land use change is significantly the performance of Kigali active human area, which plays an important role for the country to take certain decisions. Another area to take into account is the natural situation of Kigali city. Agriculture in the region does not occupy a dominant position, and with the population growth and socio-economic development, the construction area will gradually rise and speed up the process of urbanization. Thus, as a developing country, Rwanda's population continues to grow and there is low rate of utilization of land, where urbanization remains low. As mentioned earlier, the 1994 genocide massacres, population growth and urbanization processes, have been the factors driving the dramatic changes in land use. The focus on further research would be on analysis of Rwanda’s natural resources, social and economic factors that could be, the driving force of land use change.

Keywords: land use change, urbanization, Kigali City, Landsat

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7198 Urban Vegetative Planning for Ambient Ozone Pollution: An Eco-Management Approach

Authors: M. Anji Reddy, R. Uma Devi

Abstract:

Environmental planning for urban development is very much needed to reduce air pollution through the enhancement of vegetative cover in the cities like Hyderabad. This can be mainly based on the selection of appropriate native plant species as bioindicators to assess the impact of ambient Ozone. In the present study, tolerant species are suggested aimed to reduce the magnitude of ambient ozone concentrations which not only increase eco-friendly vegetation but also moderate air pollution. Hyderabad city is divided into 5 zones based on Land Use/Land Cover category further each zone divided into residential, traffic, industrial, and peri-urban areas. Highest ambient ozone levels are recorded in Industrial areas followed by traffic areas in the entire study area ( > 180 µg/m3). Biomonitoring of selected sixteen local urban plant species with the help of Air Pollution Tolerance Index (APTI) showed its susceptibility to air pollution. Statistical regression models in between the tolerant plant species and ambient ozone levels suggested five plant species namely Azardirachta indica A. Juss which have a high tolerant response to ambient ozone followed by Delonix regia Hook. along with Millingtonia hortensis L.f., Alestonia Scholaries L., and Samania saman Jacq. in the industrial and traffic areas of the study area to mitigate ambient Ozone pollution and also to improve urban greenery.

Keywords: air pollution tolerance index, bio-indicators, eco-friendly vegetation, urban greenery

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7197 The Risk Assessments of Water Quality in Selected White Water River in Malaysia

Authors: Jaffry Zakaria, Nor Azlina Hasbullah

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The research on water quality based on 'Water Quality Index' (WQI) has been on the run along Kampar River in Perak State of Malaysia. This study was conducted to achieve several key objective that determe the value of the parameters that were studied based on Water Quality Index (WQI). The parameters include Dissolved Oxygen (DO), pH, Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD) and Suspended Solids. In this study, three sampling stations were selected. Through observations from the researchers, several pollutions were found occurring along the research area such as the disposal of waste water directly without treatment from villagers, widespread dumping of solid waste and the development of the surrounding areas that contributed to the pollution of Sungai Kampar in Perak, Malaysia. Sungai Kampar is commonly used for water recreational activities as well as for bathing purposes. Results showed that Sungai Kampar is classified under category III. According to Interim National Water Quality Standard for Malaysia (INWQS), rivers in the third grade are clean but not suitable for river recreational activities. Therefore, there is a requirement to investigate and analysis the water quality of all white water rivers in Malaysia focusing on the area of water activities. The combination of technology and risk management based on risk assessments can help the recreational industry to survive in future.

Keywords: risk assessments, White Water River, water quality index (WQI), Interim National Water Quality Standard for Malaysia (INWQS)

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7196 Foreign Women Affecting the Social Life of the Ottoman Empire at the Beginning of the Twentieth Century: The Case of Lady Alice Lowther (1873-1939)

Authors: Meliha Nur Cercinli

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In the last period of the Ottoman Empire, foreign officers played important role in the political area. Behind their political activities, their wives had a considerable influence on Ottoman social life. Despite the difficult conditions, these women involved in educating girls, encouraging Ottoman women to take part in the production area. For this purpose, they opened many schools and workplaces in various regions of the capital-Istanbul. One of these women was Lady Alice Lowther, who was known as the wife of British ambassador Gerard Agustus Lowther. She arranged various organizations in order to create necessary resources to help families of martyrs. Also, she chaired the Committee for Aid to Ottoman Military Families (Asker Ailelerine Yardım Komitesi), made an effort to establish the Society for Protection Animals in Istanbul (Istanbul Himaye-i Hayvanat Cemiyeti) with the supports of The Royal Society For Prevention Cruelty For Animals. Apart from these, she was also a good observer and writer as a traveller. She wrote and published her memories with the name of Down The Old Road (1921), When It Was June (1923) Land Of Gold Mohur (1932), Moments In Portugal Or Land Of The Laurel (1939). This paper aims to analyze Lady Alice Lowther’s activities in Istanbul based on Ottoman Archive documents. In addition, her books will also be examined as they will present a different perspective regarding her experiences.

Keywords: Lady Lowther, Ottoman Empire, women history, social life

Procedia PDF Downloads 156
7195 Modelling Soil Inherent Wind Erodibility Using Artifical Intellligent and Hybrid Techniques

Authors: Abbas Ahmadi, Bijan Raie, Mohammad Reza Neyshabouri, Mohammad Ali Ghorbani, Farrokh Asadzadeh

Abstract:

In recent years, vast areas of Urmia Lake in Dasht-e-Tabriz has dried up leading to saline sediments exposure on the surface lake coastal areas being highly susceptible to wind erosion. This study was conducted to investigate wind erosion and its relevance to soil physicochemical properties and also modeling of wind erodibility (WE) using artificial intelligence techniques. For this purpose, 96 soil samples were collected from 0-5 cm depth in 414000 hectares using stratified random sampling method. To measure the WE, all samples (<8 mm) were exposed to 5 different wind velocities (9.5, 11, 12.5, 14.1 and 15 m s-1 at the height of 20 cm) in wind tunnel and its relationship with soil physicochemical properties was evaluated. According to the results, WE varied within the range of 76.69-9.98 (g m-2 min-1)/(m s-1) with a mean of 10.21 and coefficient of variation of 94.5% showing a relatively high variation in the studied area. WE was significantly (P<0.01) affected by soil physical properties, including mean weight diameter, erodible fraction (secondary particles smaller than 0.85 mm) and percentage of the secondary particle size classes 2-4.75, 1.7-2 and 0.1-0.25 mm. Results showed that the mean weight diameter, erodible fraction and percentage of size class 0.1-0.25 mm demonstrated stronger relationship with WE (coefficients of determination were 0.69, 0.67 and 0.68, respectively). This study also compared efficiency of multiple linear regression (MLR), gene expression programming (GEP), artificial neural network (MLP), artificial neural network based on genetic algorithm (MLP-GA) and artificial neural network based on whale optimization algorithm (MLP-WOA) in predicting of soil wind erodibility in Dasht-e-Tabriz. Among 32 measured soil variable, percentages of fine sand, size classes of 1.7-2.0 and 0.1-0.25 mm (secondary particles) and organic carbon were selected as the model inputs by step-wise regression. Findings showed MLP-WOA as the most powerful artificial intelligence techniques (R2=0.87, NSE=0.87, ME=0.11 and RMSE=2.9) to predict soil wind erodibility in the study area; followed by MLP-GA, MLP, GEP and MLR and the difference between these methods were significant according to the MGN test. Based on the above finding MLP-WOA may be used as a promising method to predict soil wind erodibility in the study area.

Keywords: wind erosion, erodible fraction, gene expression programming, artificial neural network

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7194 Improved Thermal Comfort in Cabin Aircraft with in-Seat Microclimate Conditioning Module

Authors: Mathieu Le Cam, Tejaswinee Darure, Mateusz Pawlucki

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Climate control of cabin aircraft is traditionally conditioned as a single unit by the environmental control system. Cabin temperature is controlled by the crew while passengers of the aircraft have control on the gaspers providing fresh air from the above head area. The small nozzles are difficult to reach and adjust to meet the passenger’s needs in terms of flow and direction. More dedicated control over the near environment of each passenger can be beneficial in many situations. The European project COCOON, funded under Clean Sky 2, aims at developing and demonstrating a microclimate conditioning module (MCM) integrated into a standard economy 3-seat row. The system developed will lead to improved passenger comfort with more control on their personal thermal area. This study focuses on the assessment of thermal comfort of passengers in the cabin aircraft through simulation on the TAITherm modelling platform. A first analysis investigates thermal comfort and sensation of passengers in varying cabin environmental conditions: from cold to very hot scenarios, with and without MCM installed in the seats. The modelling platform is also used to evaluate the impact of different physiologies of passengers on their thermal comfort as well as different seat locations. Under the current cabin conditions, a passenger of a 50th percentile body size is feeling uncomfortably cool due to the high velocity cabin air ventilation. The simulation shows that the in-seat MCM developed in COCOON project improves the thermal comfort of the passenger.

Keywords: cabin aircraft, in-seat HVAC, microclimate conditioning module, thermal comfort

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7193 Analysis of Brownfield Soil Contamination Using Local Government Planning Data

Authors: Emma E. Hellawell, Susan J. Hughes

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BBrownfield sites are currently being redeveloped for residential use. Information on soil contamination on these former industrial sites is collected as part of the planning process by the local government. This research project analyses this untapped resource of environmental data, using site investigation data submitted to a local Borough Council, in Surrey, UK. Over 150 site investigation reports were collected and interrogated to extract relevant information. This study involved three phases. Phase 1 was the development of a database for soil contamination information from local government reports. This database contained information on the source, history, and quality of the data together with the chemical information on the soil that was sampled. Phase 2 involved obtaining site investigation reports for development within the study area and extracting the required information for the database. Phase 3 was the data analysis and interpretation of key contaminants to evaluate typical levels of contaminants, their distribution within the study area, and relating these results to current guideline levels of risk for future site users. Preliminary results for a pilot study using a sample of the dataset have been obtained. This pilot study showed there is some inconsistency in the quality of the reports and measured data, and careful interpretation of the data is required. Analysis of the information has found high levels of lead in shallow soil samples, with mean and median levels exceeding the current guidance for residential use. The data also showed elevated (but below guidance) levels of potentially carcinogenic polyaromatic hydrocarbons. Of particular concern from the data was the high detection rate for asbestos fibers. These were found at low concentrations in 25% of the soil samples tested (however, the sample set was small). Contamination levels of the remaining chemicals tested were all below the guidance level for residential site use. These preliminary pilot study results will be expanded, and results for the whole local government area will be presented at the conference. The pilot study has demonstrated the potential for this extensive dataset to provide greater information on local contamination levels. This can help inform regulators and developers and lead to more targeted site investigations, improving risk assessments, and brownfield development.

Keywords: Brownfield development, contaminated land, local government planning data, site investigation

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7192 Characterization and Nanostructure Formation of Banana Peels Nanosorbent with Its Application

Authors: Opeyemi Atiba-Oyewo, Maurice S. Onyango, Christian Wolkersdorfer

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Characterization and nanostructure formation of banana peels as sorbent material are described in this paper. The transformation of this agricultural waste via mechanical milling to enhance its properties such as changed in microstructure and surface area for water pollution control and other applications were studied. Mechanical milling was employed using planetary continuous milling machine with ethanol as a milling solvent and the samples were taken at time intervals between 10 h to 30 h to examine the structural changes. The samples were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infra-red (FTIR), Transmission electron microscopy (TEM) and Brunauer Emmett and teller (BET). Results revealed three typical structures with different deformation mechanisms and the grain-sizes within the range of (71-12 nm), nanostructure of the particles and fibres. The particle size decreased from 65µm to 15 nm as the milling progressed for a period of 30 h. The morphological properties of the materials indicated that the particle shapes becomes regular and uniform as the milling progresses. Furthermore, particles fracturing resulted in surface area increment from 1.0694-4.5547 m2/g. The functional groups responsible for the banana peels capacity to coordinate and remove metal ions, such as the carboxylic and amine groups were identified at absorption bands of 1730 and 889 cm-1, respectively. However, the choice of this sorbent material for the sorption or any application will depend on the composition of the pollutant to be eradicated.

Keywords: characterization, nanostructure, nanosorbent, eco-friendly, banana peels, mechanical milling, water quality

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7191 Deliberation of Daily Evapotranspiration and Evaporative Fraction Based on Remote Sensing Data

Authors: J. Bahrawi, M. Elhag

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Estimation of evapotranspiration is always a major component in water resources management. Traditional techniques of calculating daily evapotranspiration based on field measurements are valid only for local scales. Earth observation satellite sensors are thus used to overcome difficulties in obtaining daily evapotranspiration measurements on regional scale. The Surface Energy Balance System (SEBS) model was adopted to estimate daily evapotranspiration and relative evaporation along with other land surface energy fluxes. The model requires agro-climatic data that improve the model outputs. Advance Along Track Scanning Radiometer (AATSR) and Medium Spectral Resolution Imaging Spectrometer (MERIS) imageries were used to estimate the daily evapotranspiration and relative evaporation over the entire Nile Delta region in Egypt supported by meteorological data collected from six different weather stations located within the study area. Daily evapotranspiration maps derived from SEBS model show a strong agreement with actual ground-truth data taken from 92 points uniformly distributed all over the study area. Moreover, daily evapotranspiration and relative evaporation are strongly correlated. The reliable estimation of daily evapotranspiration supports the decision makers to review the current land use practices in terms of water management, while enabling them to propose proper land use changes.

Keywords: daily evapotranspiration, relative evaporation, SEBS, AATSR, MERIS, Nile Delta

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7190 Variability of Climatic Elements in Nigeria Over Recent 100 Years

Authors: T. Salami, O. S. Idowu, N. J. Bello

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Climatic variability is an essential issue when dealing with the issue of climate change. Variability of some climate parameter helps to determine how variable the climatic condition of a region will behave. The most important of these climatic variables which help to determine the climatic condition in an area are both the Temperature and Precipitation. This research deals with Longterm climatic variability in Nigeria. Variables examined in this analysis include near-surface temperature, near surface minimum temperature, maximum temperature, relative humidity, vapour pressure, precipitation, wet-day frequency and cloud cover using data ranging between 1901-2010. Analyses were carried out and the following methods were used: - Regression and EOF analysis. Results show that the annual average, minimum and maximum near-surface temperature all gradually increases from 1901 to 2010. And they are in the same case in a wet season and dry season. Minimum near-surface temperature, with its linear trends are significant for annual, wet season and dry season means. However, the diurnal temperature range decreases in the recent 100 years imply that the minimum near-surface temperature has increased more than the maximum. Both precipitation and wet day frequency decline from the analysis, demonstrating that Nigeria has become dryer than before by the way of rainfall. Temperature and precipitation variability has become very high during these periods especially in the Northern areas. Areas which had excessive rainfall were confronted with flooding and other related issues while area that had less precipitation were all confronted with drought. More practical issues will be presented.

Keywords: climate, variability, flooding, excessive rainfall

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7189 Iron Influx, Its Root-Shoot Relations and Utilization Efficiency in Wheat

Authors: Abdul Malik Dawlatzai, Shafiqullah Rahmani

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Plant cultivars of the same species differ in their Fe efficiency. This paper studied the Fe influx and root-shoot relations of Fe at different growth stages in wheat. The four wheat cultivars (HD 2967, PDW 233, PBW 550 and PDW 291) were grown in pots in Badam Bagh agricultural researching farm, Kabul under two Fe treatments: (i) 0 mg Fe kg⁻¹ soil (soil with 2.7 mg kg⁻¹ of DTPA-extractable Fe) and (ii) 50 mg Fe kg⁻¹ soil. Root length (RL), shoot dry matter (SDM), Fe uptake, and soil parameters were measured at tillering and anthesis. Application of Fe significantly increased RL, root surface area, SDM, and Fe uptake in all wheat cultivars. Under Fe deficiency, wheat cv. HD 2967 produced 90% of its maximum RL and 75% of its maximum SDM. However, PDW 233 produced only 69% and 60%, respectively. Wheat cultivars HD 2967, and PDW 233 exhibited the highest and lowest value of root surface area and Fe uptake, respectively. The concentration difference in soil solution Fe between bulk soil and root surface (ΔCL) was maximum in wheat cultivar HD 2967, followed by PBW 550, PDW 291, and PDW 233. More depletion at the root surface causes steeper concentration gradients, which result in a high influx and transport of Fe towards root. Fe influx in all the wheat cultivars increased with the Fe application, but the increase was maximum, i.e., 4 times in HD 2967 and minimum, i.e., 2.8 times in PDW 233. It can be concluded that wheat cultivars HD 2967 and PBW 550 efficiently utilized Fe as compared to other cultivars. Additionally, iron efficiency of wheat cultivars depends upon uptake of each root segment, i.e., the influx, which in turn depends on depletion of Fe in the rhizosphere during vegetative phase and higher utilization efficiency of acquired Fe during reproductive phase that governs the ultimate grain yield.

Keywords: Fe efficiency, Fe influx, Fe uptake, Rhizosphere

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7188 City Buses and Sustainable Urban Mobility in Kano Metropolis 1967-2015: An Historical Perspective

Authors: Yusuf Umar Madugu

Abstract:

Since its creation in 1967, Kano has tremendously undergone political, social and economic transformations. Public urban transportation has been playing a vital role in sustaining economic growth of Kano metropolis, especially with the existence of modern buses with the regular network of roads, in all the main centers of trade. This study, therefore, centers on the role of intra-city buses in molding the economy of Kano. Its main focus is post-colonial Kano (i.e. 1967-2015), a period that witnessed rapid expansion of commercial activities and ever increasing urbanization which goes along with it population explosion. The commuters patronized the urban transport, a situation that made the business lucrative. More so, the traders who had come from within and outside Kano relied heavily on commercial vehicles to transport their merchandise to their various destinations. Commercial road transport system, therefore, had become well organized in Kano with a significant number of people earning their means of livelihood from it. It also serves as a source of revenue to governments at different levels. However, the study of transport and development as an academic discipline is inter-disciplinary in nature. This study, therefore, employs the services and the methodologies of other disciplines such as Geography, History, Urban and Regional Planning, Engineering, Computer Science, Economics, etc. to provide a comprehensive picture of the issues under investigation. The source materials for this study included extensive use of written literature and oral information. In view of the crucial importance of intra-city commercial transport services, this study demonstrates its role in the overall economic transformation of the study area. It generally also, contributed in opening up a new ground and looked into the history of commercial transport system. At present, Kano Metropolitan area is located between latitude 110 50’ and 12007’, and longitude 80 22’ and 80 47’ within the Semi-Arid Sudan Savannah Zone of West Africa about 840kilometers of the edge of the Sahara desert. The Metropolitan area has expanded over the years and has become the third largest conurbation in Nigeria with a population of about 4million. It is made up of eight local government areas viz: Kano Municipal, Gwale, Dala, Tarauni, Nasarawa, Fage, Ungogo, and Kumbotso.

Keywords: assessment, buses, city, mobility, sustainable

Procedia PDF Downloads 223
7187 Delineation of Oil – Polluted Sites in Ibeno LGA, Nigeria, Using Microbiological and Physicochemical Characterization

Authors: Ime R. Udotong, Justina I. R. Udotong, Ofonime U. M. John

Abstract:

Mobil Producing Nigeria Unlimited (MPNU), a subsidiary of ExxonMobil and the highest crude oil & condensate producer in Nigeria has its operational base and an oil terminal, the Qua Iboe terminal (QIT) located at Ibeno, Nigeria. Other oil companies like Network Exploration and Production Nigeria Ltd, Frontier Oil Ltd; Shell Petroleum Development Company Ltd; Elf Petroleum Nigeria Ltd and Nigerian Agip Energy, a subsidiary of the Italian ENI E&P operate onshore, on the continental shelf and in deep offshore of the Atlantic Ocean, respectively with the coastal waters of Ibeno, Nigeria as the nearest shoreline. This study was designed to delineate the oil-polluted sites in Ibeno, Nigeria using microbiological and physico-chemical characterization of soils, sediments and ground and surface water samples from the study area. Results obtained revealed that there have been significant recent hydrocarbon inputs into this environment as observed from the high counts of hydrocarbonoclastic microorganisms in excess of 1% at all the stations sampled. Moreover, high concentrations of THC, BTEX and heavy metals contents in all the samples analyzed corroborate the high recent crude oil input into the study area. The results also showed that the pollution of the different environmental media sampled were of varying degrees, following the trend: Ground water > surface water > sediments > soils.

Keywords: microbiological characterization, oil-polluted sites, physico-chemical analyses, total hydrocarbon content

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7186 Spatio-Temporal Dynamics of Snow Cover and Melt/Freeze Conditions in Indian Himalayas

Authors: Rajashree Bothale, Venkateswara Rao

Abstract:

Indian Himalayas also known as third pole with 0.9 Million SQ km area, contain the largest reserve of ice and snow outside poles and affect global climate and water availability in the perennial rivers. The variations in the extent of snow are indicative of climate change. The snow melt is sensitive to climate change (warming) and also an influencing factor to the climate change. A study of the spatio-temporal dynamics of snow cover and melt/freeze conditions is carried out using space based observations in visible and microwave bands. An analysis period of 2003 to 2015 is selected to identify and map the changes and trend in snow cover using Indian Remote Sensing (IRS) Advanced Wide Field Sensor (AWiFS) and Moderate Resolution Imaging Spectroradiometer(MODIS) data. For mapping of wet snow, microwave data is used, which is sensitive to the presence of liquid water in the snow. The present study uses Ku-band scatterometer data from QuikSCAT and Oceansat satellites. The enhanced resolution images at 2.25 km from the 13.6GHz sensor are used to analyze the backscatter response to dry and wet snow for the period of 2000-2013 using threshold method. The study area is divided into three major river basins namely Brahmaputra, Ganges and Indus which also represent the diversification in Himalayas as the Eastern Himalayas, Central Himalayas and Western Himalayas. Topographic variations across different zones show that a majority of the study area lies in 4000–5500 m elevation range and the maximum percent of high elevated areas (>5500 m) lies in Western Himalayas. The effect of climate change could be seen in the extent of snow cover and also on the melt/freeze status in different parts of Himalayas. Melt onset day increases from east (March11+11) to west (May12+15) with large variation in number of melt days. Western Himalayas has shorter melt duration (120+15) in comparison to Eastern Himalayas (150+16) providing lesser time for melt. Eastern Himalaya glaciers are prone for enhanced melt due to large melt duration. The extent of snow cover coupled with the status of melt/freeze indicating solar radiation can be used as precursor for monsoon prediction.

Keywords: Indian Himalaya, Scatterometer, Snow Melt/Freeze, AWiFS, Cryosphere

Procedia PDF Downloads 259
7185 Identifying the Conservation Gaps in Poorly Studied Protected Area in the Philippines: A Study Case of Sibuyan Island

Authors: Roven Tumaneng, Angelica Kristina Monzon, Ralph Sedricke Lapuz, Jose Don De Alban, Jennica Paula Masigan, Joanne Rae Pales, Laila Monera Pornel, Dennis Tablazon, Rizza Karen Veridiano, Jackie Lou Wenceslao, Edmund Leo Rico, Neil Aldrin Mallari

Abstract:

Most protected area management plans in the Philippines, particularly the smaller and more remote islands suffer from insufficient baseline data, which should provide the bases for formulating measureable conservation targets and appropriate management interventions for these protected areas. Attempts to synthesize available data particularly on cultural and socio-economic characteristic of local peoples within and outside protected areas also suffer from the lack of comprehensive and detailed inventories, which should be considered in designing adaptive management interventions to be used for those protected areas. Mt Guiting-guiting Natural Park (MGGNP) located in Sibuyan Island is one of the poorly studied protected areas in the Philippines. In this study, we determined the highly biologically important areas of the protected area using Maximum Entropy approach (MaxEnt) from environmental predictors (i.e., topographic, bioclimatic,land cover, and soil image layers) derived from global remotely sensed data and point occurrence data of species of birds and trees recorded during field surveys on the island. A total of 23 trigger species of birds and trees was modeled and stacked to generate species richness maps for biological high conservation value areas (HCVAs). Forest habitat change was delineated using dual-polarised L-band ALOS-PALSAR mosaic data at 25 meter spatial resolution, taken at two acquisition years 2007 and 2009 to provide information on forest cover ad habitat change in the island between year 2007 and 2009. Determining the livelihood guilds were also conducted using the data gathered from171 household interviews, from which demographic and livelihood variables were extracted (i.e., age, gender, number of household members, educational attainment, years of residency, distance from forest edge, main occupation, alternative sources of food and resources during scarcity months, and sources of these alternative resources).Using Principal Component Analysis (PCA) and Kruskal-Wallis test, the diversity and patterns of forest resource use by people in the island were determined with particular focus on the economic activities that directly and indirectly affect the population of key species as well as to identify levels of forest resource use by people in different areas of the park.Results showed that there are gaps in the area occupied by the natural park, as evidenced by the mismatch of the proposed HCVAs and the existing perimeters of the park. We found out that subsistence forest gathering was the possible main driver for forest degradation out of the eight livelihood guilds that were identified in the park. Determining the high conservation areas and identifyingthe anthropogenic factors that influence the species richness and abundance of key species in the different management zone of MGGNP would provide guidance for the design of a protected area management plan and future monitoring programs. However, through intensive communication and consultation with government stakeholders and local communities our results led to setting conservation targets in local development plans and serve as a basis for the reposition of the boundaries and reconfiguration of the management zones of MGGNP.

Keywords: conservation gaps, livelihood guilds, MaxEnt, protected area

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7184 Relationship between Reproduction Performances and Coat Characteristics of Montbeliarde Cows during Hot Season in Algeria

Authors: Sara Lamari, Toufik Madani

Abstract:

This study aimed to explore the relationship between reproduction performances and coat characteristics of Montbéliarde cows born in Algeria or imported from Europe during the hot season in Algeria. Hair coat traits (hair coat color, Hair Weight, hair length, the number of hair per unit area, total hair diameters and hair medulla diameters) were estimated in 18 imported cattle and 49 locally born cows. These traits were measured in an area of 20cm below the dorsal line in the center of the thorax. Results showed that hair coats were significantly different between locally born and imported cows. Imported cows had whiter coats when compared to locally born cows for Montbéliarde cows. A significant effect of total hair diameter was observed on the interval from calving to conception (IC) for imported Montbéliarde cows, suggesting less incidence of heat stress on reproduction efficiency of cows with thin diameter hair coats. Montbéliarde cows with short hair coat registered significantly more number of mating per conception (2, 28±1, 93 Vs. 1,67±0,92) and IC (98,04±78,81Vs 74.53 ± 35.60 days) when compared to cows with long hairs. Hair works as a temperature regulator in association with muscles in the skin and may affect reproduction performances during hit stress season. It can be assumed that the length and a total diameter of hairs for the Montbeliarde breed appears to be related to their reproductive efficiency.

Keywords: hair coat, reproduction, Montbeliarde cow, hot season

Procedia PDF Downloads 164
7183 Activities of Processors in Domestication/Conservation and Processing of Oil Bean (Pentaclethra macrophylla) in Enugu State, South East Nigeria

Authors: Iwuchukwu J. C., Mbah C.

Abstract:

There seems to be dearth on information on how oil bean is being exploited, processed and conserved locally. This gap stifles initiatives on the evaluation of the suitability of the methods used and the invention of new and better methods. The study; therefore, assesses activities of processors in domestication/conservation and processing of oil bean (Pentaclethra macrophylla) Enugu State, South East Nigeria. Three agricultural zones, three blocks, nine circles and seventy-two respondents that were purposively selected made up the sample for the study. Data were presented in percentage, chart and mean score. The result shows that processors of oil bean in the area were middle-aged, married with relatively large household size and long years of experience in processing. They sourced oil bean they processed from people’s farmland and sourced information on processing of oil bean from friends and relatives. Activities involved in processing of oil bean were boiling, dehulling, washing, sieving, slicing, wrapping. However, the sequence of these activities varies among these processors. Little or nothing was done by the processors towards the conservation of the crop while poor storage and processing facilities and lack of knowledge on modern preservation technique were major constraints to processing of oil bean in the area. The study concluded that efforts should be made by governments and processors through cooperative group in provision of processing and storage facility for oil bean while research institute should conserve and generate improved specie of the crop to arouse interest of the farmers and processors on the crop which will invariably increase productivity.

Keywords: conservation, domestication, oil bean, processing

Procedia PDF Downloads 307
7182 Economic Analysis of Cowpea (Unguiculata spp) Production in Northern Nigeria: A Case Study of Kano Katsina and Jigawa States

Authors: Yakubu Suleiman, S. A. Musa

Abstract:

Nigeria is the largest cowpea producer in the world, accounting for about 45%, followed by Brazil with about 17%. Cowpea is grown in Kano, Bauchi, Katsina, Borno in the north, Oyo in the west, and to the lesser extent in Enugu in the east. This study was conducted to determine the input–output relationship of Cowpea production in Kano, Katsina, and Jigawa states of Nigeria. The data were collected with the aid of 1000 structured questionnaires that were randomly distributed to Cowpea farmers in the three states mentioned above of the study area. The data collected were analyzed using regression analysis (Cobb–Douglass production function model). The result of the regression analysis revealed the coefficient of multiple determinations, R2, to be 72.5% and the F ration to be 106.20 and was found to be significant (P < 0.01). The regression coefficient of constant is 0.5382 and is significant (P < 0.01). The regression coefficient with respect to labor and seeds were 0.65554 and 0.4336, respectively, and they are highly significant (P < 0.01). The regression coefficient with respect to fertilizer is 0.26341 which is significant (P < 0.05). This implies that a unit increase of any one of the variable inputs used while holding all other variables inputs constants, will significantly increase the total Cowpea output by their corresponding coefficient. This indicated that farmers in the study area are operating in stage II of the production function. The result revealed that Cowpea farmer in Kano, Jigawa and Katsina States realized a profit of N15,997, N34,016 and N19,788 per hectare respectively. It is hereby recommended that more attention should be given to Cowpea production by government and research institutions.

Keywords: coefficient, constant, inputs, regression

Procedia PDF Downloads 408
7181 Flood Mapping Using Height above the Nearest Drainage Model: A Case Study in Fredericton, NB, Canada

Authors: Morteza Esfandiari, Shabnam Jabari, Heather MacGrath, David Coleman

Abstract:

Flood is a severe issue in different places in the world as well as the city of Fredericton, New Brunswick, Canada. The downtown area of Fredericton is close to the Saint John River, which is susceptible to flood around May every year. Recently, the frequency of flooding seems to be increased, especially after the fact that the downtown area and surrounding urban/agricultural lands got flooded in two consecutive years in 2018 and 2019. In order to have an explicit vision of flood span and damage to affected areas, it is necessary to use either flood inundation modelling or satellite data. Due to contingent availability and weather dependency of optical satellites, and limited existing data for the high cost of hydrodynamic models, it is not always feasible to rely on these sources of data to generate quality flood maps after or during the catastrophe. Height Above the Nearest Drainage (HAND), a state-of-the-art topo-hydrological index, normalizes the height of a basin based on the relative elevation along with the stream network and specifies the gravitational or the relative drainage potential of an area. HAND is a relative height difference between the stream network and each cell on a Digital Terrain Model (DTM). The stream layer is provided through a multi-step, time-consuming process which does not always result in an optimal representation of the river centerline depending on the topographic complexity of that region. HAND is used in numerous case studies with quite acceptable and sometimes unexpected results because of natural and human-made features on the surface of the earth. Some of these features might cause a disturbance in the generated model, and consequently, the model might not be able to predict the flow simulation accurately. We propose to include a previously existing stream layer generated by the province of New Brunswick and benefit from culvert maps to improve the water flow simulation and accordingly the accuracy of HAND model. By considering these parameters in our processing, we were able to increase the accuracy of the model from nearly 74% to almost 92%. The improved model can be used for generating highly accurate flood maps, which is necessary for future urban planning and flood damage estimation without any need for satellite imagery or hydrodynamic computations.

Keywords: HAND, DTM, rapid floodplain, simplified conceptual models

Procedia PDF Downloads 150
7180 Further Development in Predicting Post-Earthquake Fire Ignition Hazard

Authors: Pegah Farshadmanesh, Jamshid Mohammadi, Mehdi Modares

Abstract:

In nearly all earthquakes of the past century that resulted in moderate to significant damage, the occurrence of postearthquake fire ignition (PEFI) has imposed a serious hazard and caused severe damage, especially in urban areas. In order to reduce the loss of life and property caused by post-earthquake fires, there is a crucial need for predictive models to estimate the PEFI risk. The parameters affecting PEFI risk can be categorized as: 1) factors influencing fire ignition in normal (non-earthquake) condition, including floor area, building category, ignitability, type of appliance, and prevention devices, and 2) earthquake related factors contributing to the PEFI risk, including building vulnerability and earthquake characteristics such as intensity, peak ground acceleration, and peak ground velocity. State-of-the-art statistical PEFI risk models are solely based on limited available earthquake data, and therefore they cannot predict the PEFI risk for areas with insufficient earthquake records since such records are needed in estimating the PEFI model parameters. In this paper, the correlation between normal condition ignition risk, peak ground acceleration, and PEFI risk is examined in an effort to offer a means for predicting post-earthquake ignition events. An illustrative example is presented to demonstrate how such correlation can be employed in a seismic area to predict PEFI hazard.

Keywords: fire risk, post-earthquake fire ignition (PEFI), risk management, seismicity

Procedia PDF Downloads 380
7179 Effects of Surface Insulation of Silicone Rubber Composites in HVDC

Authors: Min-Hae Park, Ju-Na Hwang, Cheong-won Seo, Ji-Ho Kim, Kee-Joe Lim

Abstract:

Polymeric insulators are high hardness, corrosion resistant, lightweight and also good dielectric strength in electric equipment. For such reasons, the amount of polymeric insulators is increased consistently abroad. The current outdoor insulators are replaced by polymeric insulators. Silicone rubber of polymeric insulators is widely used in insulation materials for outdoor application since it has excellent electrical characteristics and high surface hydrophobic. However, it can be evade exposure to pollutant on surface using at outdoor. It also improve the pollution for dust and smoke due to the large are increasing, because most of the industrial area in which the electric power loads are concentrated are located at the coastal area with salt attack. Thus it is important to detect the main cause of the deterioration for outdoor insulation materials. But there has no standards for valuation to apply reliably and determine accurately deterioration under DC, still lacks DC characteristic researches in proportion to AC. In addition, a lot of ATH was added to improve tracking resistivity of silicone rubber, although the problem has been brought up about falling sharply mechanical properties. Therefore, we might compare surface resistivities of silicone rubber compounding of three kinds of filler. In this paper, specimens of silicone rubber composite usable as outdoor insulators were prepared. Micro-silica (SiO2), nano- alumina (Al2O3) and nano-ATH (Al(OH)3) were used in additives. The study aims to investigate properties of DC surface insulation on silicone rubber composite which were filled with various fillers from surface resistivity measurement and salt-fog test.

Keywords: composite, silicone rubber, surface insulation, HVDC

Procedia PDF Downloads 407
7178 Assessment of Forest Resource Exploitation in the Rural Communities of District Jhelum

Authors: Rubab Zafar Kahlon, Ibtisam Butt

Abstract:

Forest resources are deteriorating and experiencing decline around the globe due to unsustainable use and over exploitation. The present study was an attempt to determine the relationship between human activities, forest resource utilization, extraction methods and practices of forest resource exploitation in the district Jhelum of Pakistan. For this purpose, primary sources of data were used which were collected from 8 villages through structured questionnaire and tabulated in Microsoft Excel 365 and SPSS 22 was used for multiple linear regression analysis. The results revealed that farming, wood cutting, animal husbandry and agro-forestry were the major occupations in the study area. Most commonly used resources included timber 26%, fuelwood 25% and fodder 19%. Methods used for resource extraction included gathering 49%, plucking 34% trapping 11% and cutting 6%. Population growth, increased demand of fuelwood and land conversion were the main reasons behind forest degradation. Results for multiple linear regression revealed that Forest based activities, sources of energy production, methods used for wood harvesting and resource extraction and use of fuelwood for energy production contributed significantly towards extensive forest resource exploitation with p value <0.5 within the study area. The study suggests that effective measures should be taken by forest department to control the unsustainable use of forest resources by stringent management interventions and awareness campaigns in Jhelum district.

Keywords: forest resource, biodiversity, expliotation, human activities

Procedia PDF Downloads 91
7177 Thermal Management of Ground Heat Exchangers Applied in High Power LED

Authors: Yuan-Ching Chiang, Chien-Yeh Hsu, Chen Chih-Hao, Sih-Li Chen

Abstract:

The p-n junction temperature of LEDs directly influences their operating life and luminous efficiency. An excessively high p-n junction temperature minimizes the output flux of LEDs, decreasing their brightness and influencing the photon wavelength; consequently, the operating life of LEDs decreases and their luminous output changes. The maximum limit of the p-n junction temperature of LEDs is approximately 120 °C. The purpose of this research was to devise an approach for dissipating heat generated in a confined space when LEDs operate at low temperatures to reduce light decay. The cooling mode of existing commercial LED lights can be divided into natural- and forced convection cooling. In natural convection cooling, the volume of LED encapsulants must be increased by adding more fins to increase the cooling area. However, this causes difficulties in achieving efficient LED lighting at high power. Compared with forced convection cooling, heat transfer through water convection is associated with a higher heat transfer coefficient per unit area; therefore, we dissipated heat by using a closed loop water cooling system. Nevertheless, cooling water exposed to air can be easily influenced by environmental factors. Thus, we incorporated a ground heat exchanger into the water cooling system to minimize the influence of air on cooling water and then observed the relationship between the amounts of heat dissipated through the ground and LED efficiency.

Keywords: helical ground heat exchanger, high power LED, ground source cooling system, heat dissipation

Procedia PDF Downloads 577
7176 Performance Evaluation of Hemispherical Basin Type Solar Still

Authors: Husham Mahmood Ahmed

Abstract:

For so many reasons, fresh water scarcity is one of major problems facing the world and in particularly in the third world in the Northern Africa, the Middle East, the Southwest of Asia, and many other desert areas. Solar distillation offers one of the most promising solutions of renewable energy to this aggravated situation. The main obstacle hindering the spread of the use of solar technology for fresh water production is its low efficiency. Therefore, enhancing the solar stills performances by studying the parameters affecting their productivity and implementing new ideas and a different design are the main goals of the investigators in recent years. The present research is experimental work that tests a new design of solar still with a hemispherical top cover for water desalination with and without external reflectors under the climate of the Kingdom of Bahrain during the autumn season. The hemispherical cover has a base diameter of 1m and a depth of 0.4m, die cast from a 6 mm thick Lexan plastic sheet. The net effective area was 0.785 m2. It has been found that the average daily production rate obtained from the hemispherical top cover solar still is 3.610 liter/day. This yield is 11.1% higher than the yield of a conventional simple type single slope solar still having 20ᴼ slope glass cover and a larger effective area of 1 m2 obtained in previous research under similar climatic conditions. It has also been found that adding 1.2m long by 0.15 curved reflectors increased the yield of the hemispherical solar still by 5.5 %, while the 1.2 long by 0.3m curved reflector increased the yield by about 8%.

Keywords: hemispherical solar still, solar desalination, solar energy, the Northern Africa

Procedia PDF Downloads 392