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Building Construction, Road Works and Waste Management: Impact of Anthropogenic Actions on Flooding in Yenagoa, Nigeria
Get PDF Floods are generally seen as natural occurrences with other underlying causal factors. These factors are both natural and anthropogenic in nature and often induce or exacerbate flood episodes in the environment. As it were, while some of these factors stem from natural ecological cycles, others are engendered by accumulated anthropogenic actions or inactions. This study aims to examine three independent documents comprising of two technical reports commissioned by the Bayelsa State government in Yenagoa and contiguous neighborhoods and narratives from a PhD flood research with a view to understanding the nature and dynamics of anthropogenic actions causing flooding in Bayelsa State. The objectives include; a systematic review of the government commissioned technical reports on floods in Yenagoa and other related documents; identify and highlight both natural and anthropogenic causes of flooding in the study area; recommend an appropriate course of action. The study adopted direct personal observation, photography and secondary data analysis to obtain data. Findings from the combination of these documents highlight some of the deliberate human actions and/or inactions taken by both Government and private developers regarding incidents of flooding within the Yenagoa Metropolis. Based on the document’s review, three key anthropogenic actions were identified; building construction and other physical development activities, waste management and drainage systems and public infrastructure development. Specific recommendations such as the adoption of a holistic approach towards harmonized flood data management framework, effective implementation of such policies to tackle these identified challenges, undertake EIA, hydrologic and hydrographic studies, as well as base line studies before embarking on any developmental projects, desilting of clogged drainage culverts and proper alignment of road projects to reduce incursion and subsequent impediment of free flow of runoffs were made
Influence of Water-Repellent Admixtures on the Water-Resistance of Unstabilized and Stabilized Compressed Earth Blocks
Get PDF The low durability of water action has been the main issue of earth construction since ancient times. In this way, sustainable solutions are needed to improve the earthen building materials water-resistance performance without significantly changing their appearance and eco-friendly nature. This study aims at characterizing the water-resistance of compressed earth blocks (CEB) produced with or without different types of colorless water-repellent admixtures. To this end, different types of unstabilized and 8% cement stabilized CEB were protected with two post-surface treatments, namely a silane-siloxane based surface water-repellent (SWR) and a natural linseed oil (LO), as well as one olein based integral water-repellent (IWR). Unprotected reference CEB were also considered for comparison purposes. More sustainable CEB were produced with 20% replacement of earth by recycling waste building materials. The CEB were tested in terms of compressive and flexural strength, capillary water absorption, immersion absorption, water permeability, low-pressure water absorption, and water erosion resistance from drip and spray tests. The influence of the moisture content on the compressive strength was also analysed. The cement-stabilization and water-repellent treatments were able to overcome the non-water-resistant nature of unstabilized CEB. In general, the best performance was attained with SWR, followed by IWR. The LO was less effective in reducing the long-term absorption but was able to protect unstabilized CEB from light rainfall simulated conditions. Under severe water erosion, the surface treatments were less effective, but water penetration was reduced up to near 40%. The mechanical strength, total porosity, water permeability and immersion absorption were not significantly affected by water-repellent products. Moreover, the mechanical strength reduction of stabilized CEB after saturation was about 30%, regardless of the water-repellent treatment. The main contribution of water-repellent admixtures occurred in all properties involving capillary absorption
How to Determine Individual Risk Due to Toxic, Fire, and Explosion Accidents in a Hydrocarbon Processing Area?
Get PDFAccidents in the processing and storage of hydrocarbons can cause severe damage to people, not only within the facility but also in nearby places. In those cases, the occurrence of a major accident is considered. Moreover, there are many studies on how to determine the impact on people of these types of events. However, there is a real need to establish a methodology that integrates risk analysis techniques with other artificial intelligence ones and, in this way, to include the likelihood of the domino effect. For this reason, this research aims to determine the individual risk due to the domino effect of toxic, fire, and explosion accidents that can occur in a hydrocarbon processing area. For this purpose, a logical sequence of analysis of eight fundamental stages was made. In addition, the Bayesian and Petri networks are developed to determine the joint probability of the domino effect at different levels and the damages caused by toxicity, respectively. Finally, the individual risk is obtained, expressed using isorisk maps. As main results, these maps confirm that three deaths can occur up to 200 meters, while 250 will cause approximately four in just 10 years, values that decrease to 500 meters and are considered high according to specialized literature. Hence, this methodology is vital to quantify the possible damages of toxic accidents, fires, and explosions on people in the hydrocarbon processing industry
Polluted Waters Use in the Urban Agriculture and Its Impact on the Quality of the Grown Vegetables
Get PDFUrban agriculture has become a common practice in major urban agglomerations, particularly in the mining region of Katanga, in the Democratic Republic of Congo (DRC). However, this agriculture is based on the production of vegetables grown on the soil contaminated by industrial water and domestic wastewater, wherein one finds heavy metals and pathogenic microbes capable of endangering the consumer’s health. This work has been carried out in view of contributing to the consumer’s health protection and endeavours at establishing, based on physicochemical and mineral analyses of water samples, the soil used in the urban agriculture and edible plants, a link between the use of contaminated waters in the urban agriculture, the build-up of heavy metals in the soil and the possible contamination by heavy metals of vegetables grown (amaranths and broccolis) in the Kasungami district and consumed by the population living in the City of Lubumbashi (DRC). The results given by the analyses of water, soils and vegetable samples revealed that, apart from cobalt, other heavy metals were present in water used in the urban agriculture to concentrations below quality standards. As for the soil, it contained heavy metals to concentration reputed phytotoxic. However, only the broccolis were contaminated with lead, contrarily to amaranths in which heavy metals were present to concentrations below quality standards. These findings enabled concluding that urban agriculture of vegetables encountered in the large agglomerations of the DRC could endanger the consumers’ health and measures need to be taken in view of preventing heavy metal from entering the food chain
Principle of Neural Network and Its Main Types: Review
Get PDF In this paper, an overview of the artificial neural networks is presented. Their main and popular types such as the multilayer feedforward neural network (MLFFNN), the recurrent neural network (RNN), and the radial basis function (RBF) are investigated. Furthermore, the main advantages and disadvantages of each type are included as well as the training process
Generalized Path Optimization Problem for a Weighted Digraph over an Additively Idempotent Semiring
Get PDFIn this paper, a generalized path optimization problem for a weighted digraph (i.e., directed graph) over an additively idempotent semiring was considered. First, the conditions for power convergence of a matrix over an additively idempotent semiring were investigated. Then we proved that the path optimization problem is associated with powers of the adjacency matrix of the weighted digraph. The classical matrix power method for the shortest path problem on the min-plus algebra was generalized to the generalized path optimization problem. The proposed generalized path optimization model encompasses different path optimization problems, including the longest path problem, the shortest path problem, the maximum reliability path problem, and the maximum capacity path problem. Finally, for the four special cases, we illustrate the pictorial representations of the graphs with example data and the proposed method
Treatments of Gibberellic Acid for Vegetative Growth, Tuber Yield and Quality of Potato (Solanum tuberosum L.) in the Central Highlands of Ethiopia
Get PDF The productivity of potato is low owing to a number of constraints including poor sprouting due to dormancy, which leads to delayed planting and poor crop emergence and vigor. The study was conducted during 2008-2009 with the objectives to determine the effects of different methods and rates of gibberellic acid (GA3) application on dormancy attributes, tuber yield and quality of potato, and its subsequent generation of Gera cultivar. Five levels of GA3 (0, 250,500,750 and 1000 ppm), as haulm application a week prior to haulm destruction, and five levels of GA3 (10, 20, 30, 40 and 50 ppm), as dipping treatments immediately after harvest for 24hrs, were used as treatments. The treatments were arranged in randomized completed block design with three replications both for planting and storage. The result showed that GA3 application affected dormancy period, tuber yield and quality. Haulm applications of GA3 increased marketable tuber and tuber yield per hill as compared to untreated tubers. Moreover, haulm application of GA3 increased dry matter content as compared to the control, while the increment in the dry matter content was also observed in response to dipping the seed tuber. In the same manner, dipping seed tubers in GA3 solution increased tuber specific gravity of the next generation as compared to the control. Therefore, significant increase in tuber number and weight due to GA3 application contributed to the increase of total tuber yield. Both haulm application and dipping treatments of GA3 at higher rates resulted in high total, marketable tuber yield along with significant dry matter content and tuber specific gravity, which help the producers to boost their produce
Novel Use of Chlorine Dioxide Granules as an Alternative to Methyl Bromide Soil Fumigation
Get PDF Two greenhouse studies were conducted to evaluate the effectiveness of chlorine dioxide (ClO2) granules as a soil fumigation alternative for methyl bromide. The objective of the first study was to determine the efficacy of chlorine dioxide granules to inactivate Bacillus subtilis spore samples placed in two soils and positioned at two soil depths in soil tubes. The objective of the second study was to measure ClO2 gas concentrations released over multiple days in the two soils. The granules were evenly distributed in the soils with datalogger/sensors positioned at two different locations (headspace and soil matrix). The first study achieved a maximum spore log10 reduction of 4.12 and 5.82 for play sand and mixed soil, respectively, for inoculated samples placed 8 cm deep in the soil tubes with a chlorine dioxide rate of 240 g/tube. There was a 21-fold increase in percent organic matter for the mixed soil when compared to the play sand soil. The increase in organic matter in the mixed soil resulted in a 1.7 log10 reduction decrease due to the absorption of the gas onto the organic matter. In the second study, chlorine dioxide was collected at the bottom of the soil instead of volatilizing into the headspace of the soil tube because it is denser than air. The ClO2 at the bottom of the soil was 3.95x and 3.8x higher than the headspace gas concentration for the mixed and play sand soil, respectively, as averaged over all test runs and periods. Both studies show that the chlorine dioxide granules are a promising alternative to soil fumigation with methyl bromide. Further research is needed to refine the granule formulation release rates and develop more economical application rates
Evaluation of a Mobile Two-Stage Decontamination System using a Power Washer Combined with Eight Disinfectant Treatments
Get PDF With the increased frequency of pandemics that threaten the spread of zoonotic diseases associated with agricultural commodities and trade, it is becoming a national priority to advance more effective and efficient decontamination technologies. A field study was conducted to evaluate a two-stage, mobile power washing system. The study factors were power washing, disinfectant type, sample surfaces, and number of repeat disinfectant applications. Study factors were evaluated based on log10 reduction of viable Bacillus subtilis spores on inoculated sample surfaces. Diluted bleach from Clorox Concentrate, applied without power washing, had the greatest sporicidal activity when applied three times to non-porous surfaces (steel washers), which resulted in a 3.0 log10 reduction of viable spores. The two-stage decontamination treatment with the greatest sporicidal activity was power washing porous surfaces (wool fabric), followed by three applications of EasyDECON DF-200, resulting in a 4.8 log10 reduction of viable spores. The results showed that power washing was the most important factor for dislodging spores and overall decontamination effectiveness. Also, sporicidal activity was slightly greater for non-porous surfaces compared to porous surfaces. Repeated applications of disinfectants resulted in little to no improvement in sporicidal efficacy. The results from this field study were comparable with a similar two-stage equipment decontamination study, which was conducted the year before this study. Further research is needed to evaluate large stationary decontamination systems and refine any interactions between power washing parameters and innovative sanitation methods
Thermomodernization of Historical Buildings with Residential Facades
Get PDF Historic buildings, as well as much newer ones, with architecturally attractive facades, will not be thermomodernized from the outside, Because of their high value stands in the way. One such case is mentioned in this article, in which an analysis of external vertical partitions was carried out, in terms of heat and humidity in a small residential building located in southern Poland and built in 1930. The article describes a hygrothermal analysis of the above mentioned partitions, before and after thermomodernization, which should assess the legitimacy and effectiveness of using controversial methods of insulation of external building partitions from their internal sides. The article is a summary of a five-year observation and research of the object, after its thermomodernization in 2015. The analysis was focused on its vertical partitions