Search results for: compound Poisson lognormal distribution

Authors: Pitchayanin Sukholthaman

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Gradually accumulated, the enormous amount of waste has caused tremendous adverse impacts to the world. Bangkok, Thailand, is chosen as an urban city of a developing country having coped with serious MSW problems due to the vast amount of waste generated, ineffective and improper waste management problems. Waste generation is the most important factor for successful planning of MSW management system. Thus, the prediction of MSW is a very important role to understand MSW distribution and characteristic; to be used for strategic planning issues. This study aims to find influencing variables that affect the amount of Bangkok MSW generation quantity.

Keywords: MSW generation, MSW quantity prediction, MSW management, multiple regression, Bangkok

Procedia PDF Downloads 421

Authors: Jing Ma, Xindong An

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Green infrastructure, the most important aspect of improving the quality of life, has been a crucial element of the liveability measurement. With demanding of more liveable urban environment from increasing population in city area, access to green infrastructure in walking distance should be taken into consideration. This article exemplifies the study on accessibility measurement of green infrastructure in central Auckland (New Zealand), using network analysis tool on the basis of GIS, to verify the accessibility levels of green infrastructure. It analyses the overall situation of green infrastructure and draws some conclusions on the city’s different levels of accessibility according to the categories and facilities distribution, which provides valuable references and guidance for the future facility improvement in planning strategies.

Keywords: quality of life, green infrastructure, GIS, accessibility

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Authors: Abdelfetah Laouzai, Rachid Ouafi

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In a traffic network, users usually choose their way so that it reduces their travel time between pairs origin-destination. This behavior might seem selfish as it produces congestions in different parts of the network. The traffic assignment problem (TAP) models the interactions between congestion and user travel decisions to obtain vehicles flows over each axis of the traffic network. The resolution methods of TAP serve as a tool allows predicting users’ distribution, identifying congesting points and affecting the travelers’ behavior in the choice of their route in the network following dynamic data. In this article, we will present a review about specific resolution approach of TAP. A comparative analysis is carried out on those approaches so that it highlights the characteristics, advantages and disadvantages of each.

Keywords: network traffic, travel decisions, approaches, traffic assignment, flows

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Authors: Shan-Hong Ying, Ying-Fang Wang

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A surrogate approach was deployed for assessing exposures of multiple chemicals at the selected working area of coating processes and applied to assess the exposure concentration of similar exposed groups using the same chemicals but different formula ratios. For the selected area, 6 to 12 portable photoionization detector (PID) were placed uniformly in its workplace to measure its total VOCs concentrations (CT-VOCs) for 6 randomly selected workshifts. Simultaneously, one sampling strain was placed beside one of these portable PIDs, and the collected air sample was analyzed for individual concentration (CVOCi) of 5 VOCs (xylene, butanone, toluene, butyl acetate, and dimethylformamide). Predictive models were established by relating the CT-VOCs to CVOCi of each individual compound via simple regression analysis. The established predictive models were employed to predict each CVOCi based on the measured CT-VOC for each the similar working area using the same portable PID. Results show that predictive models obtained from simple linear regression analyses were found with an R2 = 0.83~0.99 indicating that CT-VOCs were adequate for predicting CVOCi. In order to verify the validity of the exposure prediction model, the sampling analysis of the above chemical substances was further carried out and the correlation between the measured value (Cm) and the predicted value (Cp) was analyzed. It was found that there is a good correction between the predicted value and measured value of each measured chemical substance (R2=0.83~0.98). Therefore, the surrogate approach could be assessed the exposure concentration of similar exposed groups using the same chemicals but different formula ratios. However, it is recommended to establish the prediction model between the chemical substances belonging to each coater and the direct-reading PID, which is more representative of reality exposure situation and more accurately to estimate the long-term exposure concentration of operators.

Keywords: exposure assessment, exposure prediction model, surrogate approach, TVOC

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Authors: Nafsi K. Ashraf, C. V. Vipin, V. Anantha Subramanian

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This paper reports the design of a waterjet propulsion system for an amphibious vehicle based on circulation distribution over the camber line for the sections of the impeller and stator. In contrast with the conventional waterjet design, the inlet duct is straight for water entry parallel and in line with the nozzle exit. The extended nozzle after the stator bowl makes the flow more axial further improving thrust delivery. Waterjet works on the principle of volume flow rate through the system and unlike the propeller, it is an internal flow system. The major difference between the propeller and the waterjet occurs at the flow passing the actuator. Though a ducted propeller could constitute the equivalent of waterjet propulsion, in a realistic situation, the nozzle area for the Waterjet would be proportionately larger to the inlet area and propeller disc area. Moreover, the flow rate through impeller disk is controlled by nozzle area. For these reasons the waterjet design is based on pump systems rather than propellers and therefore it is important to bring out the characteristics of the flow from this point of view. The analysis is carried out using computational fluid dynamics. Design of waterjet propulsion is carried out adapting the axial flow pump design and performance analysis was done with three-dimensional computational fluid dynamics (CFD) code. With the varying environmental conditions as well as with the necessity of high discharge and low head along with the space confinement for the given amphibious vehicle, an axial pump design is suitable. The major problem of inlet velocity distribution is the large variation of velocity in the circumferential direction which gives rise to heavy blade loading that varies with time. The cavitation criteria have also been taken into account as per the hydrodynamic pump design. Generally, waterjet propulsion system can be parted into the inlet, the pump, the nozzle and the steering device. The pump further comprises an impeller and a stator. Analytical and numerical approaches such as RANSE solver has been undertaken to understand the performance of designed waterjet propulsion system. Unlike in case of propellers the analysis was based on head flow curve with efficiency and power curves. The modeling of the impeller is performed using rigid body motion approach. The realizable k-ϵ model has been used for turbulence modeling. The appropriate boundary conditions are applied for the domain, domain size and grid dependence studies are carried out.

Keywords: amphibious vehicle, CFD, impeller design, waterjet propulsion

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Authors: Wasim Sajjad, Manzoor Ahmad, Sundas Qadir, Muhammad Rafiq, Fariha Hasan, Richard Tehan, Kerry L. McPhail, Aamer Ali Shah

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Aim: This study aims to investigate the possible radiation protective role of a compatible solute in the tolerance of radio-halophilic bacterium against stresses, like desiccation and exposure to ionizing radiation. Methods and Results: Nine different radio-resistant bacteria were isolated from desert soil, where strain WMA-LM19 was chosen for detailed studies on the basis of its high tolerance for ultraviolet radiation among all these isolates. 16S rRNA gene sequencing indicated that the bacterium was closely related to Stenotrophomonas sp. (KT008383). A bacterial milking strategy was applied for extraction of intracellular compatible solutes in 70% (v/v) ethanol, which were purified by high-performance liquid chromatography (HPLC). The compound was characterized as ectoine by 1H and 13C nuclear magnetic resonance (NMR), and mass spectrometry (MS). Ectoine demonstrated more efficient preventive activity (54.80%) to erythrocyte membranes and also inhibited oxidative damage to proteins and lipids in comparison to the standard ascorbic acid. Furthermore, a high level of ectoine-mediated protection of bovine serum albumin against ionizing radiation (1500-2000 Jm-2) was observed, as indicated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis. Conclusion: The results indicated that ectoine can be used as a potential mitigator and radio-protective agent to overcome radiation- and salinity-mediated oxidative damage in extreme environments. Significance and Impact of the Study: This study shows that ectoine from radio-halophiles can be used as a potential source in topical creams as sunscreen. The investigation of ectoine as UV protectant also changes the prospective that radiation resistance is specific only to molecular adaptation.

Keywords: ectoine, anti-oxidant, stenotrophomonas sp., ultraviolet radiation

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Authors: Tshegofatso Galekgathege

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Poor water quality is of great concern to human health as it can cause disease outbreaks. A standard practice today, in developed countries, is that people should be provided with safe-reliable drinking water, as safe drinking water is recognized as a basic human right and a cost effective measure of reducing diseases. Over 1.1 billion people worldwide lack access to a safe water supply and as a result, the majority are forced to use polluted surface or groundwater. It is widely accepted that our water supply systems are susceptible to the intentional or accidental contamination .Water quality degradation may occur anywhere in the path that water takes from the water source to the consumer. Chlorine is believed to be an effective tool in disinfecting water, but its concentration may decrease with time due to consumption by chemical reactions. This shows that we are at the risk of being infected by waterborne diseases if chlorine in water falls below the required level of 0.2-1mg/liter which should be maintained in water and some contaminants enter into the water distribution system. It is believed that the lack of adequate sanitation also contributes to the contamination of water globally. This study therefore, assesses drinking water contamination from the source to the consumer by identifying the point vulnerable to contamination from the source to the consumer in the study area .To identify the point vulnerable to contamination, water was sampled monthly from boreholes, water treatment plant, water distribution system (WDS), service reservoirs and consumer taps from all the twenty (20) villages of Palapye region. Sampled water was then taken to the laboratory for testing and analysis of microbiological and chemical parameters. Water quality analysis were then compared with Botswana drinking water quality standards (BOS32:2009) to see if they comply. Major sources of water contamination identified during site visits were the livestock which were found drinking stagnant water from leaking pipes in 90 percent of the villages. Soils structure around the area was negatively affected because of livestock movement even vegetation in the area. In conclusion microbiological parameters of water in the study area do not comply with drinking water standards, some microbiological parameters in water indicated that livestock do not only affect land degradation but also the quality of water. Chlorine has been applied to water over some years but it is not effective enough thus preventative measures have to be developed, to prevent contaminants from reaching water. Remember: Prevention is better than cure.

Keywords: land degradation, leaking systems, livestock, water contamination

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Authors: Gaelle Candel, David Naccache

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t-SNE is an embedding method that the data science community has widely used. It helps two main tasks: to display results by coloring items according to the item class or feature value; and for forensic, giving a first overview of the dataset distribution. Two interesting characteristics of t-SNE are the structure preservation property and the answer to the crowding problem, where all neighbors in high dimensional space cannot be represented correctly in low dimensional space. t-SNE preserves the local neighborhood, and similar items are nicely spaced by adjusting to the local density. These two characteristics produce a meaningful representation, where the cluster area is proportional to its size in number, and relationships between clusters are materialized by closeness on the embedding. This algorithm is non-parametric. The transformation from a high to low dimensional space is described but not learned. Two initializations of the algorithm would lead to two different embeddings. In a forensic approach, analysts would like to compare two or more datasets using their embedding. A naive approach would be to embed all datasets together. However, this process is costly as the complexity of t-SNE is quadratic and would be infeasible for too many datasets. Another approach would be to learn a parametric model over an embedding built with a subset of data. While this approach is highly scalable, points could be mapped at the same exact position, making them indistinguishable. This type of model would be unable to adapt to new outliers nor concept drift. This paper presents a methodology to reuse an embedding to create a new one, where cluster positions are preserved. The optimization process minimizes two costs, one relative to the embedding shape and the second relative to the support embedding’ match. The embedding with the support process can be repeated more than once, with the newly obtained embedding. The successive embedding can be used to study the impact of one variable over the dataset distribution or monitor changes over time. This method has the same complexity as t-SNE per embedding, and memory requirements are only doubled. For a dataset of n elements sorted and split into k subsets, the total embedding complexity would be reduced from O(n²) to O(n²=k), and the memory requirement from n² to 2(n=k)², which enables computation on recent laptops. The method showed promising results on a real-world dataset, allowing to observe the birth, evolution, and death of clusters. The proposed approach facilitates identifying significant trends and changes, which empowers the monitoring high dimensional datasets’ dynamics.

Keywords: concept drift, data visualization, dimension reduction, embedding, monitoring, reusability, t-SNE, unsupervised learning

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Authors: Chinumani Choudhury

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Heavy metal contamination is an alarming problem, which poses a serious risk to human health and the surrounding geology. Soils get contaminated with heavy metals due to the un-regularized industrial discharge of the toxic metal-rich effluents. Under such a condition, the remediation of the contaminated sites becomes imperative for a sustainable, safe, and healthy environment. Phytoextraction, which involves the removal of heavy metals from the soil through root absorption and uptake, is a viable remediation technique, which ensures extraction of the toxic inorganic compound available in the soil even at low concentrations. The soil present in the Silghat Region of Assam, India, is mostly contaminated with Zinc (Zn) and Lead (Pb), having concentrations as high as to cause a serious environmental problem if proper measures are not taken. In the present study, an extensive experimental study was carried out to understand the effectiveness of two commonly planted trees in Assam, namely, i) Indian Pennywort and ii) Fenugreek, in the removal of heavy metals from the contaminated soil. The basic characterization of the soil in the contaminated site of the Silghat region was performed and the field concentration of Zn and Pb was recorded. Various long-term laboratory pot tests were carried out by sowing the seeds of Indian Pennywort and Fenugreek in a soil, which was spiked, with a very high dosage of Zn and Pb. The tests were carried out for different concentration of a particular heavy metal and the individual effectiveness in the absorption of the heavy metal by the plants were studied. The concentration of the soil was monitored regularly to assess the rate of depletion and the simultaneous uptake of the heavy metal from the soil to the plant. The amount of heavy metal uptake by the plant was also quantified by analyzing the plant sample at the end of the testing period. Finally, the study throws light on the applicability of the studied plants in the field for effective remediation of the contaminated sites of Assam.

Keywords: phytoextraction, heavy-metals, Indian pennywort, fenugreek

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Authors: Ismail Haddad, Djamel Herbadji, Aissa Belmeguenai, Selma Boumerdassi

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in this paper, we provide a novel approach for image encryption that employs the Fibonacci matrix and an enhanced fractional order chaotic map. The enhanced map overcomes the drawbacks of the classical map, especially the limited chaotic range and non-uniform distribution of chaotic sequences, resulting in a larger encryption key space. As a result, this strategy improves the encryption system's security. Our experimental results demonstrate that our proposed algorithm effectively encrypts grayscale images with exceptional efficiency. Furthermore, our technique is resistant to a wide range of potential attacks, including statistical and entropy attacks.

Keywords: image encryption, logistic map, fibonacci matrix, grayscale images

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Authors: Lígia Pimentel, Miguel Pereira, Manuela Pintado

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Wheat germ is a by-product of wheat flour refining. Despite this by-product being a source of proteins, lipids, fibres and complex carbohydrates, and consequently a valuable ingredient to be used in Food Industry, only few applications have been studied. The main goal of this study was to assess the potential prebiotic effect of natural wheat germ. The prebiotic potential was evaluated by in vitro assays with individual microbial strains (Lactobacillus paracasei L26 and Lactobacillus casei L431). A simulated model of the gastrointestinal digestion was also used including the conditions present in the mouth (artificial saliva), oesophagus–stomach (artificial gastric juice), duodenum (artificial intestinal juice) and ileum. The effect of natural wheat germ and wheat germ after digestion on the growth of lactic acid bacteria was studied by growing those microorganisms in de Man, Rogosa and Sharpe (MRS) broth (with 2% wheat germ and 1% wheat germ after digestion) and incubating at 37 ºC for 48 h with stirring. A negative control consisting of MRS broth without glucose was used and the substrate was also compared to a commercial prebiotic fructooligosaccharides (FOS). Samples were taken at 0, 3, 6, 9, 12, 24 and 48 h for bacterial cell counts (CFU/mL) and pH measurement. Results obtained showed that wheat germ has a stimulatory effect on the bacteria tested, presenting similar (or even higher) results to FOS, when comparing to the culture medium without glucose. This was demonstrated by the viable cell counts and also by the decrease on the medium pH. Both L. paracasei L26 and L. casei L431 could use these compounds as a substitute for glucose with an enhancement of growth. In conclusion, we have shown that wheat germ stimulate the growth of probiotic lactic acid bacteria. In order to understand if the composition of gut bacteria is altered and if wheat germ could be used as potential prebiotic, further studies including faecal fermentations should be carried out. Nevertheless, wheat germ seems to have potential to be a valuable compound to be used in Food Industry, mainly in the Bakery Industry.

Keywords: by-products, functional ingredients, prebiotic potential, wheat germ

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Authors: Mohammad Faheem, M. Tabish Rehman, Mohd Danishuddin, Asad U. Khan

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The worldwide dissemination of CTX-M type β-lactamases is a threat to human health. Previously, we have reported the spread of blaCTX-M-15 gene in different clinical strains of Enterobacteriaceae from the hospital settings of Aligarh in north India. In view of the varying resistance pattern against cephalosporins and other β-lactam antibiotics, we intended to understand the correlation between MICs and catalytic activity of CTX-M-15. In this study, steady-state kinetic parameters and MICs were determined on E. coli DH5α transformed with blaCTX-M-15 gene that was cloned from Enterobacter cloacae (EC-15) strain of clinical background. The effect of conventional β-lactamase inhibitors (clavulanic acid, sulbactam and tazobactam) on CTX-M-15 was also studied. We have found that tazobactam is the best among these inhibitors against CTX-M-15. The inhibition characteristic of tazobactam is defined by its very low IC50 value (6 nM), high affinity (Ki = 0.017 µM) and better acylation efficiency (k+2/K9 = 0.44 µM-1s-1). It forms an acyl-enzyme covalent complex, which is quite stable (k+3 = 0.0057 s-1). Since increasing resistance has been reported against conventional b-lactam antibiotic-inhibitor combinations, we aspire to design a non-b-lactam core containing b-lactamase inhibitor. For this, we screened ZINC database and performed molecular docking to identify a potential non-β-lactam based inhibitor (ZINC03787097). The MICs of cephalosporin antibiotics in combination with this inhibitor gave promising results. Steady-state kinetics and molecular docking studies showed that ZINC03787097 is a reversible inhibitor which binds non-covalently to the active site of the enzyme through hydrogen bonds and hydrophobic interactions. Though, it’s IC50 (180 nM) is much higher than tazobactam, it has good affinity for CTX-M-15 (Ki = 0.388 µM). This study concludes that ZINC03787097 compound can be used as seed molecule to design more efficient non-b-lactam containing b-lactamase inhibitor that could evade pre-existing bacterial resistance mechanisms.

Keywords: ESBL, non-b-lactam-b-lactamase inhibitor, bioinformatics, biomedicine

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Authors: Rade M. Ciric, Nikola L. J. Rajakovic

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This paper presents a curriculum of the subject small power plants and renewable energy sources, dealing with the concept of distributed generation, renewable energy sources, hydropower, wind farms, geothermal power plants, cogeneration plants, biogas plants of agriculture and animal origin, solar power and fuel cells. The course is taught the manner of connecting small power plants to the grid, the impact of small generators on the distribution system, as well as economic, environmental and legal aspects of operation of distributed generators.

Keywords: distributed generation, renewable energy sources, energy policy, curriculum

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Authors: Kasipandi Muniyandi, Parimelazhagan Thangaraj

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Plants are important prospective wealth of a country, combination of local health care information about a specific plant together with data published by several groups of scientists, can help in deciding whether it should be considered acceptable for medicinal use. In the developed countries, too, plant-derived drugs may be of importance. The wide variety of ailments that are being treated with Plectranthus is an indication of the medicinal value of the genus. A number of species are not toxic and so may be taken orally, whilst others are used topically on the skin or as enemas. This study was designed to evaluate the different properties of Plectranthus stocksii and the aerial parts were collected and extracted with petroleum ether, chloroform, ethyl acetate, acetone and methanol by Soxhlet apparatus and finally macerated with hot water. The quantification assays revealed that, leaf methanol extract showed higher total phenolic (415.41 mg GAE/ g extract) and tannin (177.53 mg GAE/ g extract) contents whereas leaf ethyl acetate exhibited higher flavonoids (777.11 mg RE/ g extract) content. The antioxidant efficiency of the extracts was analyzed by various radical scavenging assays. Among the different antioxidant assays, leaf ethyl acetate extract showed higher free radical scavenging activities against DPPH (IC50 = 3.46 µg/mL), ABTS (27417.65 µM TE/ g extract), FRAP (152.17 mM Fe(II)E/ mg extract) NO• radical (21.46%) and Superoxide radical (IC50 = 24.16 µg/mL) assays. All the parts P. stocksii extracts showed significant protection against OH• induced DNA damage at 50 µg concentration. The HPLC analysis of leaf ethyl acetate extract revealed the presence of Quercetin (30.29 µg/mg of extract) was the major compound. Anticancer activity of leaf ethyl acetate extract showed better IC50 values were 48.87 and 36.08 µg/ mL against MCF-7 and Caco-2 respectively. From this study, P. stocksii can act as a potent antioxidant and cytotoxic antimicrobial agent. The scope for drug development from this plant is endless and there is undoubtedly a call for further research in pharmaceutical industries.

Keywords: antioxidant, cytotoxicity, phenolics, plectranthus stocksii

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Authors: J. T. Johnson, R. A. Atule, E. Gbodo

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The widespread problem of infant malnutrition in developing countries has stirred efforts in research, development and extension by both local and international organizations. As a result, the formulation and development of nutritious weaning foods from local and readily available raw materials which are cost effective has become imperative in many developing countries. Thus, local and readily available raw materials where used to compound and develop nutritious new infant formulae. The materials used for this study include maize, millet, cowpea, pumpkin, fingerlings, and fish bone. The materials where dried and blended to powder. The powders were weighed in the ratio of 4:4:4:3:1:1 respectively and were then mixed properly. Analysis of nutritive value was conducted on the formulae and compared with NAN-2 standard and results reveals that the formulae had reasonable amount of moisture, lipids, carbohydrate, protein, and fibre. Although NAN-2 was superior in both carbohydrate and protein, the new infant formula was higher in mineral elements, vitamins, fibre, and lipids. All the essentials vitamins and both macro and micro minerals where found in appreciable quantity capable of meeting the biochemical and physiological demand of the body while the anti-nutrients composition were significantly below FAO and WHO safe limits. Finally, the compounded infant formulae was feed to a set of albino Wistar rats while some other set of rats was feed with NAN-2 for the period of twenty seven (27) days and body weight was measure at three days intervals. The results of body weight changes was spectacular as their body weight over shot or almost double that of those animals that were feed with NAN-2 at each point of measurement. The results suggest that the widespread problem of infant malnutrition in the developing world especially among the low income segment of the society can now be reduced if not totally eradicated since nutritive and cost effective weaning formulae can be prepared locally from common readily available materials.

Keywords: formulation, nutritive value, local, materials

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Authors: A. Cervantes-Diaz, B. Sevilla-Moran, Manuel Alcami, Al Mokhtar Lamsabhi, J. L. Alonso-Prados, P. Sandin-España

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Profoxydim is a post-emergence herbicide belonging to the cyclohexanedione oxime family, used to control weeds in rice crops. The use of soil organic amendments has increased significantly in the last decades, and their effects on the behavior of many herbicides are still unknown. Additionally, it is known that photolysis is an important degradation process to be considered when evaluating the persistence of this family of herbicides in the environment. In this work, the photodegradation of profoxydim in an amended paddy soil-water system with alperujo compost was studied. Photodegradation experiments were carried out under laboratory conditions using simulated solar light (Suntest equipment) in order to evaluate the reaction kinetics of the active substance. The photochemical behavior of profoxydim was investigated in soil with and without alperujo amendment. Furthermore, due to the rice crop characteristics, profoxydim photodegradation in water in contact with these types of soils was also studied. Determination of profoxydim degradation kinetics was performed by High-Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD). Furthermore, we followed the evolution of resulting transformation by-products, and their tentative identification was achieved by mass spectrometry. All the experiments allowed us to fit the data of profoxydim photodegradation to a first-order kinetic. Photodegradation of profoxydim was very rapid in all cases. The half-lives in aqueous matrices were in the range of 86±0.3 to 103±0.5 min. The addition of alperujo amendment to the soil produced an increase in the half-life from 62±0.2 min (soil) to 75±0.3 min (amended soil). In addition, a comparison to other organic amendments was also performed. Results showed that the presence of the organic amendment retarded the photodegradation in paddy soil and water. Regarding degradation products, the main process involved was the cleavage of the oxime moiety giving rise to the formation of the corresponding imine compound.

Keywords: by-products, herbicide, organic amendment, photodegradation, profoxydim

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Authors: Van Tran Thi Thuy, Dukjoon Kim

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A series of pH- and thermosensitive poly(N-isopropyl acrylamide-co-acrylic acid) were synthesized by radical polymerization and grafted on poly succinimide backbones. The poly succinimide derivatives synthesized were coated on iron oxide magnetic nanoparticles for potential applications in drug delivery systems with theranostic and molecular imaging. The structure of polymer shell was confirmed by FT-IR, H-NMR spectroscopies. Its thermal behavior was tested by UV-Vis spectroscopy. The particle size and its distribution are measured by dynamic light scattering (DLS) and transmission electron microscope (TEM). The mean diameter of the core-shell structure is from 20 to 80 nm.

Keywords: magnetic, nano, PNIPAM, polysuccinimide

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Authors: Amina Merabet, Ali Iznasni, Abderrezzak Benhabib

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Impulse buying is of strategic importance to distributors. Currently, distribution companies rely heavily on contextual variables (music, smells, colors, sound, design ...) in order to push customers towards purchase and consumption. As such, a crucial way for commercial brands to increase sales is to stimulate impulse buying. For this reason, this study aims at identifying the factors that initiate and encourage impulse buying, as well as the levers that help distributors highlight effective marketing techniques in order to encourage consumers to make impulse purchase. Thus, we try to show, upon a field survey of 590 buyers, the impact of situational elements of both the store and the product on achieving impulse buying.

Keywords: Algerian shoppers, impulse buying, shopping environment, situational variables, product

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Authors: Todor Penchev, Dimitar Karastojanov, Ivan Altaparmakov

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For briquetting of metal chips are used hydraulic and mechanical presses. The density of the briquettes in this case is about 60% - 70 % on the density of solid metal. In this work are presented the results of experimental studies for briquetting of metal chips, by using a new technology for impact briquetting. The used chips are by Armco iron, steel, cast iron, copper, aluminum and brass. It has been found that: (i) in a controlled impact the density of the briquettes can be increases up to 30%; (ii) at the same specific impact energy Es (J/sm3) the density of the briquettes increases with increasing of the impact velocity; (iii), realization of the repeated impact leads to decrease of chips density, which can be explained by distribution of elastic waves in the briquette.

Keywords: briquetting, chips briquetting, impact briquetting, controlled impact

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Authors: Amit Kumar, Archana Gupta, Poonam Tandon, E. D. D’Silva

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Nonlinear optical (NLO) materials are the key materials for the fast processing of information and optical data storage applications. In the last decade, materials showing nonlinear optical properties have been the object of increasing attention by both experimental and computational points of view. Chalcones are one of the most important classes of cross conjugated NLO chromophores that are reported to exhibit good SHG efficiency, ultra fast optical nonlinearities and are easily crystallizable. The basic structure of chalcones is based on the π-conjugated system in which two aromatic rings are connected by a three-carbon α, β-unsaturated carbonyl system. Due to the overlap of π orbitals, delocalization of electronic charge distribution leads to a high mobility of the electron density. On a molecular scale, the extent of charge transfer across the NLO chromophore determines the level of SHG output. Hence, the functionalization of both ends of the π-bond system with appropriate electron donor and acceptor groups can enhance the asymmetric electronic distribution in either or both ground and excited states, leading to an increased optical nonlinearity. In this research, the experimental and theoretical study on the structure and vibrations of (2E)-3-[4-(methylsulfanyl) phenyl]-1-(3-bromophenyl) prop-2-en-1-one (3Br4MSP) is presented. The FT-IR and FT-Raman spectra of the NLO material in the solid phase have been recorded. Density functional theory (DFT) calculations at B3LYP with 6-311++G(d,p) basis set were carried out to study the equilibrium geometry, vibrational wavenumbers, infrared absorbance and Raman scattering activities. The interpretation of vibrational features (normal mode assignments, for instance) has an invaluable aid from DFT calculations that provide a quantum-mechanical description of the electronic energies and forces involved. Perturbation theory allows one to obtain the vibrational normal modes by estimating the derivatives of the Kohn−Sham energy with respect to atomic displacements. The molecular hyperpolarizability β plays a chief role in the NLO properties, and a systematical study on β has been carried out. Furthermore, the first order hyperpolarizability (β) and the related properties such as dipole moment (μ) and polarizability (α) of the title molecule are evaluated by Finite Field (FF) approach. The electronic α and β of the studied molecule are 41.907×10-24 and 79.035×10-24 e.s.u. respectively, indicating that 3Br4MSP can be used as a good nonlinear optical material.

Keywords: DFT, MEP, NLO, vibrational spectra

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Authors: L. Joseph, B. Farid, F. Ravelet

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Fundamental studies were performed on bifurcation, instabilities and turbulence in Taylor-Couette flow and applied to many engineering applications like astrophysics models in the accretion disks, shrouded fans, and electric motors. Such rotating machinery performances need to have a better understanding of the fluid flow distribution to quantify the power losses and the heat transfer distribution. The present investigation is focused on high gap ratio of Taylor-Couette flow with high rotational speeds, for smooth and grooved surfaces. So far, few works has been done in a very narrow gap and with very high rotation rates and, to the best of our knowledge, not with this combination with grooved surface. We study numerically the turbulent flow between two coaxial cylinders where R1 and R2 are the inner and outer radii respectively, where only the inner is rotating. The gap between the rotor and the stator varies between 0.5 and 2 mm, which corresponds to a radius ratio η = R1/R2 between 0.96 and 0.99 and an aspect ratio Γ= L/d between 50 and 200, where L is the length of the rotor and d being the gap between the two cylinders. The scaling of the torque with the Reynolds number is determined at different gaps for different smooth and grooved surfaces (and also with different number of grooves). The fluid in the gap is air. Re varies between 8000 and 30000. Another dimensionless parameter that plays an important role in the distinction of the regime of the flow is the Taylor number that corresponds to the ratio between the centrifugal forces and the viscous forces (from 6.7 X 105 to 4.2 X 107). The torque will be first evaluated with RANS and U-RANS models, and compared to empirical models and experimental results. A mesh convergence study has been done for each rotor-stator combination. The results of the torque are compared to different meshes in 2D dimensions. For the smooth surfaces, the models used overestimate the torque compared to the empirical equations that exist in the bibliography. The closest models to the empirical models are those solving the equations near to the wall. The greatest torque achieved with grooved surface. The tangential velocity in the gap was always higher in between the rotor and the stator and not on the wall of rotor. Also the greater one was in the groove in the recirculation zones. In order to avoid endwall effects, long cylinders are used in our setup (100 mm), torque is measured by a co-rotating torquemeter. The rotor is driven by an air turbine of an automotive turbo-compressor for high angular velocities. The results of the experimental measurements are at rotational speed of up to 50 000 rpm. The first experimental results are in agreement with numerical ones. Currently, quantitative study is performed on grooved surface, to determine the effect of number of grooves on the torque, experimentally and numerically.

Keywords: Taylor-Couette flow, high gap ratio, grooved surface, high speed

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Authors: Ana Claudia de Souza Costa, Beatriz de Cássia Pinheiro Goulart, Karine de Cássia Cavalari, Henrique Ceretta Oliveira, Edineis de Brito Guirardello

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Background: During the COVID-19 pandemic, nursing represents the largest category of health professionals who were on the front line. Thus, investigating the practice environment and the job satisfaction of nursing professionals during the pandemic becomes fundamental since it reflects on the quality of care and the safety climate. The aim of this study was to evaluate and compare the nursing professionals' perception of the work environment, job satisfaction, and safety climate of the different hospitals and work shifts during the COVID-19 pandemic. Method: This is a cross-sectional survey with 130 nursing professionals from public, private and mixed hospitals in Brazil. For data collection, was used an electronic form containing the personal and occupational variables, work environment, job satisfaction, and safety climate. The data were analyzed using descriptive statistics and ANOVA or Kruskal-Wallis tests according to the data distribution. The distribution was evaluated by means of the Shapiro-Wilk test. The analysis was done in the SPSS 23 software, and it was considered a significance level of 5%. Results: The mean age of the participants was 35 years (±9.8), with a mean time of 6.4 years (±6.7) of working experience in the institution. Overall, the nursing professionals evaluated the work environment as favorable; they were dissatisfied with their job in terms of pay, promotion, benefits, contingent rewards, operating procedures and satisfied with coworkers, nature of work, supervision, and communication, and had a negative perception of the safety climate. When comparing the hospitals, it was found that they did not differ in their perception of the work environment and safety climate. However, they differed with regard to job satisfaction, demonstrating that nursing professionals from public hospitals were more dissatisfied with their work with regard to promotion when compared to professionals from private (p=0.02) and mixed hospitals (p< 0.01) and nursing professionals from mixed hospitals were more satisfied than those from private hospitals (p= 0.04) with regard to supervision. Participants working in night shifts had the worst perception of the work environment related to nurse participation in hospital affairs (p= 0.02), nursing foundations for quality care (p= 0.01), nurse manager ability, leadership and support (p= 0.02), safety climate (p< 0.01), job satisfaction related to contingent rewards (p= 0.04), nature of work (p= 0.03) and supervision (p< 0.01). Conclusion: The nursing professionals had a favorable perception of the environment and safety climate but differed among hospitals regarding job satisfaction for the promotion and supervision domains. There was also a difference between the participants regarding the work shifts, being the night shifts, those with the lowest scores, except for satisfaction with operational conditions.

Keywords: health facility environment, job satisfaction, patient safety, nursing

Procedia PDF Downloads 157

Authors: Nahed M. M. Ismail, Bayoumy B. Mostafa, Ahmed Abdel-Kader, Khalil M. El-Said, Asmaa Abdel-Motleb, Hoda M. Abu Taleb

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This study was carried out in lined and unlined watercourses in Beheira and Giza governorates to investigate the effect of water canals lining on water quality and aquatic vegetations. Samples of water and aquatic plants were collected from the examining sites during four seasons in two successive years. The main ecological parameters were recorded and water quality was measured. Results showed that the mean value of water conductivity and total dissolved salts in lined sites was significantly lower than those of unlined ones (p < 0.01, p < 0.05). In Beheira, the dissolved oxygen concentrations during autumn and winter were higher in lined sites (3.93±1.3 and 9.6±1.1 ppm, respectively) than those of unlined ones (the same values of 1.2±0.6 ppm). However, it represented by lower values of 5.77±6.05 and 4.9±1.8 ppm in lined watercourses in spring and summer, respectively, comparing with those in unlined ones (14.05±5.59 and 5.83±0.8 ppm, respectively). Generally, Zn, Pb, Fe, Cd were higher in both lined and unlined sites during summer than the other seasons. However, Zn and Fe were higher in lined sites (0.78±0.37 and 17.4±4.3 ppb, respectively) during summer than that of unlined ones (0.4±0.1 and 10.95±1.93 ppb, respectively). Cu was absent during summer in lined and unlined sites and only in unlined ones during spring. Regarding to Giza sites, Cu and Pb were absent in both lined and unlined sites during summer and only in unlined ones during spring. Whereas, Fe recorded higher values in autumn in both lined (8.8±20.1 ppb) and unlined sites (15.16±3 ppb) than the other seasons. Present survey study revealed that 13 species of aquatic plants were collected from lined and unlined sites in Beheira and Giza governorates. Eichhornia crassipes, Ceratophyllum demersum, and Potamogeton sp. were the only plant species infested the examined sites during autumn and winter in Beheira. In autumn C. demersum was the only plant found in lined sites represented by highly lower significant percentage (12.5% of the all examined sites) compared to the unlined sites (50%). E. crassipes was completely absent in the lined sites during the two seasons. In spring, there is only 3 plant species in lined sites compared to 6 ones in unlined. Also, in summer, there is only 2 species in lined sites comparing with 5 in unlined. The percentage of occurrence and density of these plants was highly significant (p < 0.01, p < 0.001) higher in unlined sites compared to the lined ones during all seasons. A diversity of plant species, E. crassipes, C. demersum, Jussias repens, Lemma giba, and Polygonum serr were the most abundant in many examined sites during all seasons in Giza. In summer, the percentage of sites containing the two plants E. crassipes (83.3%) and C. demersum (50%) was highly significant (p < 0.001) higher in unlined sites compared to the lined ones (50% and 0.0%, respectively). It concluded from the results that watercourses lining may play a significant role in preserving water with a good quality and reduces the distribution of aquatic vegetation which rendered the current of water.

Keywords: aquatic plants, lining of watercourses, physicochemical parameters, water quality

Procedia PDF Downloads 135

Authors: Reza Mokhtari Malek Abadi, Mohsen Saghaei, Fatemeh Iman

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This paper investigates the indices of a creative city in Isfahan. Its main aim is to evaluate quantitative status of the creative city indices in Isfahan city, analyze the dispersion and distribution of these indices in Isfahan city. Concerning these, this study tries to analyze the creative city indices in fifteen area of Isfahan through secondary data, questionnaire, TOPSIS model, Shannon entropy and SPSS. Based on this, the fifteen areas of Isfahan city have been ranked with 12 factors of creative city indices. The results of studies show that fifteen areas of Isfahan city are not equally benefiting from creative indices and there is much difference between the areas of Isfahan city.

Keywords: grading, creative city, creative city evaluation indicators, regional planning model

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Authors: B. Suraj Aravind, M. H. M. Krishna Prasad

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There exist emerging applications of data streams that require association rule mining, such as network traffic monitoring, web click streams analysis, sensor data, data from satellites etc. Data streams typically arrive continuously in high speed with huge amount and changing data distribution. This raises new issues that need to be considered when developing association rule mining techniques for stream data. This paper proposes to introduce an improved data stream association rule mining algorithm by eliminating the limitation of resources. For this, the concept of cloud computing is used. Inclusion of this may lead to additional unknown problems which needs further research.

Keywords: data stream, association rule mining, cloud computing, frequent itemsets

Procedia PDF Downloads 501

Authors: Boitumelo Setlhare, Mduduzi P. Mokoena, Ademola O. Olaniran

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Agricultural and industrial activities have led to increasing production of xenobiotics such as 2,4-dichlorophenol (2,4-DCP), a derivative of 2,4-dichlorophenoxyacetic acid (2,4-D), which is a widely used herbicide. Bioremediation offers an efficient, cost-effective and environmentally friendly method for degradation of the compound through the activities of the various microbial enzymes involved in the catabolic pathway. The aim of this study was to isolate and characterize bacterial isolate indigenous to contaminated sites in Durban, South Africa for 2,4-DCP degradation. One bacterium capable of utilizing 2,4-DCP as sole carbon source was isolated using culture enrichment technique and identified as Pseudomonas chlororaphis strain UFB2 via PCR amplification and analysis of 16S rRNA gene sequence. This isolate was able to degrade up to 75.11% of 2,4-DCP in batch cultures within 10 days, with the degradation rate constant of 0.14 mg/l/d. Phylogenetic analysis revealed the relatedness of this bacterial isolate to other Pseudomonas sp. previously characterized for chlorophenol degradation. PCR amplification of the catabolic genes involved in 2,4-DCP degradation revealed the presence of the correct amplicons for phenol hydroxylase (600 bp), catechol 1,2-dioxygenase (214 bp), muconate isomerase (851 bp), cis-dienelactone hydrolase (577 bp), and trans-dienelactone hydrolase (491 bp) genes. Enzyme assays revealed activity as high as 21840 mU/mg, 15630 mU/mg, 2340 mU/mg and 1490 mU/mg obtained for phenol hydroxylase, catechol 1,2-dioxygenase, cis-dienelactone hydroxylase and trans-dienelactone hydroxylase, respectively. The absence of catechol 2,3-dioxygenase gene and the corresponding enzyme in this isolate suggests that the organism followed ortho-pathway for 2,4-DCP degradation. Furthermore, the absence of malaycetate reductase genes showed that the bacterium may not be able to completely mineralize 2,4-DCP. Further studies are required to optimize 2,4-DCP degradation by this isolate as well as to elucidate the mechanism of 2,4-DCP degradation.

Keywords: biodegradation, catechol 1, 2-dioxygenase, 2, 4-dichlorophenol, phenol hydroxylase, Pseudomonas chlororaphis

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Authors: Zahra Yadollahi, Marjan Motiei, Natalia Kazantseva, Petr Saha

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Chitosan (CS)-whey protein isolate (WPI) core-shell nanoparticles were synthesized through self-assembly of whey protein isolated polyanions and chitosan polycations in the presence of tripolyphosphate (TPP) as a crosslinker. The formation of this type of nanostructures with narrow particle size distribution is crucial for developing delivery systems since the functional characteristics highly depend on their sizes. To achieve this goal, the nanostructure was optimized by varying the concentrations of WPI, CS, and TPP in the reaction mixture. The chemical characteristics, surface morphology, and particle size of the nanoparticles were evaluated.

Keywords: whey protein isolated, chitosan, nanoparticles, delivery system

Procedia PDF Downloads 93

Authors: Vagisha Rawal, Anupam V. Sharma, Tarun Kumar Vats, Ashok Kumar Singh

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The antifeedant activity of methanol and hexane extract of leaves and seeds of Datura innoxia (Mill.) (Solanaceae) was evaluated against the 5th instar Spodoptera litura (F.) (Lepidoptera: Noctuidae) larvae in choice and no-choice leaf disc bioassays under laboratory conditions. These larvae when given a choice between the ‘control’ and ‘treated’ leaf discs in choice bioassays, consumed significantly (p ˂ 0.05) greater area of the ‘control’ leaf discs compared to those treated with the crude extracts of leaves and seeds of D. innoxia. The Antifeedant Index (AFI) for 5% concentration of the hexane extract of Datura seeds (DSHE) was 43.3% and 38.5% for methanol extract of Datura seeds (DSME). On the other hand, these values were 34.1% for the hexane extract of Datura leaves (DLHE), and 31.0% for the methanol extract of Datura leaves (DLME), respectively. In no-choice bioassays also, there was a significant (p˂0.05) reduction in the larval consumption of ‘treated’ leaf discs compared to the ‘control’ leaf discs. Maximum AFI was recorded at 5% concentration of the extracts of both the leaves and seeds with 47.7% for DSHE against 40.0% (DSME) and 39.4% for DLHE compared with 38.4% (DLME). Moreover, DSHE was found to have the maximum antifeedant effect irrespective of its concentration in comparison to the other crude extracts of leaves or seeds of D. innoxia. It is evident from these results that the crude methanol and hexane extracts of leaves and seeds of D. innoxia exhibited potent antifeedant activity against the 5th instar S. litura larvae. Also, the use of the bioactive compound(s) present in these extracts can prove to be an effective, eco-friendly, viable and sustainable component that can be integrated in IPM programs for the management of this economically important polyphagous insect pest in the Indian subcontinent.

Keywords: antifeedant activity, antifeedant index, datura innoxia, spodoptera litura

Procedia PDF Downloads 521

Authors: V. Konjik, J. Schwartz, R. Sandhoff, M. Mack

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The rising number of multi-resistant pathogens demands the development of new antibiotics in order to reduce the lethal risk of infections. Here, we investigate roseoflavin, a vitamin B2 analogue which is produced by Streptomyces davawensis and Streptomyces cinnabarinus. We consider roseoflavin to be a 'Trojan horse' compound. Its chemical structure is very similar to riboflavin but in fact it is a toxin. Furthermore, it is a clever strategy with regard to the delivery of an antibiotic to its site of action but also with regard to the production of this chemical: The producer cell has only to convert a vitamin (which is already present in the cytoplasm) into a vitamin analog. Roseoflavin inhibits the activity of Flavin depending proteins, which makes up to 3.5 % of predicted proteins in organisms sequenced so far. We sequentially knocked out gene clusters and later on single genes in order to find the ones which are involved in the roseoflavin biosynthesis. Consequently, we identified the gene rosB, coding for the protein carrying out the first step of roseoflavin biosynthesis, starting form Flavin mononucleotide. Here we show, that the protein RosB has so far unknown features. It is per se an oxidoreductase, a decarboxylase and an aminotransferase, all rolled into one enzyme. A screen of cofactors revealed needs of oxygen, NAD+, thiamine and glutamic acid to carry out its function. Surprisingly, thiamine is not only needed for the decaboxylation step, but also for the oxidation of 8-demethyl-8-formyl Flavin mononucleotide. We had managed to isolate three different Flavin intermediates with different oxidation states, which gave us a mechanistic insight of RosB functionality. Our work points to a so far new function of thiamine in Streptomyces davawensis. Additionally, RosB could be extremely useful for chemical synthesis. Careful engineering of RosB may allow the site-specific replacement of methyl groups by amino groups in polyaromatic compounds of commercial interest. Finally, the complete clarification of the roseoflavin biosynthesis opens the possibility of engineering cost-effective roseoflavin producing strains.

Keywords: antibiotic, flavin analogue, roseoflavin biosynthesis, vitamin B2

Procedia PDF Downloads 243

Authors: R. S. Al Abri, M. H. Albadi, M. H. Al Abri, U. K. Al Rasbi, M. H. Al Hasni, S. M. Al Shidi

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This paper presents an analysis study on the impacts of the changes of the capacitor banks, the loss of a transformer, and the installation of distributed generation on the voltage total harmonic distortion and harmonic resonance. The study is applied in a real system in Oman, Sohar Industrial Port–C Substation Network. Frequency scan method and Fourier series analysis method are used with the help of EDSA software. Moreover, the results are compared with limits specified by national Oman distribution code.

Keywords: power quality, capacitor bank, voltage total harmonics distortion, harmonic resonance, frequency scan

Procedia PDF Downloads 617