Search results for: root canal length
1098 The Impact of Two Factors on EFL Learners' Fluency
Authors: Alireza Behfar, Mohammad Mahdavi
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Nowadays, in the light of progress in the world of science, technology and communications, mastery of learning international languages is a sure and needful matter. In learning any language as a second language, progress and achieving a desirable level in speaking is indeed important for approximately all learners. In this research, we find out how preparation can influence L2 learners' oral fluency with respect to individual differences in working memory capacity. The participants consisted of sixty-one advanced L2 learners including MA students of TEFL at Isfahan University as well as instructors teaching English at Sadr Institute in Isfahan. The data collection consisted of two phases: A working memory test (reading span test) and a picture description task, with a one-month interval between the two tasks. Speaking was elicited through speech generation task in which the individuals were asked to discuss four topics emerging in two pairs. The two pairs included one simple and one complex topic and was accompanied by planning time and without any planning time respectively. Each topic was accompanied by several relevant pictures. L2 fluency was assessed based on preparation. The data were then analyzed in terms of the number of syllables, the number of silent pauses, and the mean length of pauses produced per minute. The study offers implications for strategies to improve learners’ both fluency and working memory.Keywords: two factors, fluency, working memory capacity, preparation, L2 speech production reading span test picture description
Procedia PDF Downloads 2171097 Genetic Algorithm Methods for Determination Over Flow Coefficient of Medium Throat Length Morning Glory Spillway Equipped Crest Vortex Breakers
Authors: Roozbeh Aghamajidi
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Shaft spillways are circling spillways used generally for emptying unexpected floods on earth and concrete dams. There are different types of shaft spillways: Stepped and Smooth spillways. Stepped spillways pass more flow discharges through themselves in comparison to smooth spillways. Therefore, awareness of flow behavior of these spillways helps using them better and more efficiently. Moreover, using vortex breaker has great effect on passing flow through shaft spillway. In order to use more efficiently, the risk of flow pressure decreases to less than fluid vapor pressure, called cavitations, should be prevented as far as possible. At this research, it has been tried to study different behavior of spillway with different vortex shapes on spillway crest on flow. From the viewpoint of the effects of flow regime changes on spillway, changes of step dimensions, and the change of type of discharge will be studied effectively. Therefore, two spillway models with three different vortex breakers and three arrangements have been used to assess the hydraulic characteristics of flow. With regard to the inlet discharge to spillway, the parameters of pressure and flow velocity on spillway surface have been measured at several points and after each run. Using these kinds of information leads us to create better design criteria of spillway profile. To achieve these purposes, optimization has important role and genetic algorithm are utilized to study the emptying discharge. As a result, it turned out that the best type of spillway with maximum discharge coefficient is smooth spillway with ogee shapes as vortex breaker and 3 number as arrangement. Besides it has been concluded that the genetic algorithm can be used to optimize the results.Keywords: shaft spillway, vortex breaker, flow, genetic algorithm
Procedia PDF Downloads 3661096 DEMs: A Multivariate Comparison Approach
Authors: Juan Francisco Reinoso Gordo, Francisco Javier Ariza-López, José Rodríguez Avi, Domingo Barrera Rosillo
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The evaluation of the quality of a data product is based on the comparison of the product with a reference of greater accuracy. In the case of MDE data products, quality assessment usually focuses on positional accuracy and few studies consider other terrain characteristics, such as slope and orientation. The proposal that is made consists of evaluating the similarity of two DEMs (a product and a reference), through the joint analysis of the distribution functions of the variables of interest, for example, elevations, slopes and orientations. This is a multivariable approach that focuses on distribution functions, not on single parameters such as mean values or dispersions (e.g. root mean squared error or variance). This is considered to be a more holistic approach. The use of the Kolmogorov-Smirnov test is proposed due to its non-parametric nature, since the distributions of the variables of interest cannot always be adequately modeled by parametric models (e.g. the Normal distribution model). In addition, its application to the multivariate case is carried out jointly by means of a single test on the convolution of the distribution functions of the variables considered, which avoids the use of corrections such as Bonferroni when several statistics hypothesis tests are carried out together. In this work, two DEM products have been considered, DEM02 with a resolution of 2x2 meters and DEM05 with a resolution of 5x5 meters, both generated by the National Geographic Institute of Spain. DEM02 is considered as the reference and DEM05 as the product to be evaluated. In addition, the slope and aspect derived models have been calculated by GIS operations on the two DEM datasets. Through sample simulation processes, the adequate behavior of the Kolmogorov-Smirnov statistical test has been verified when the null hypothesis is true, which allows calibrating the value of the statistic for the desired significance value (e.g. 5%). Once the process has been calibrated, the same process can be applied to compare the similarity of different DEM data sets (e.g. the DEM05 versus the DEM02). In summary, an innovative alternative for the comparison of DEM data sets based on a multinomial non-parametric perspective has been proposed by means of a single Kolmogorov-Smirnov test. This new approach could be extended to other DEM features of interest (e.g. curvature, etc.) and to more than three variablesKeywords: data quality, DEM, kolmogorov-smirnov test, multivariate DEM comparison
Procedia PDF Downloads 1061095 Characterization of the Intestinal Microbiota: A Signature in Fecal Samples from Patients with Irritable Bowel Syndrome
Authors: Mina Hojat Ansari, Kamran Bagheri Lankarani, Mohammad Reza Fattahi, Ali Reza Safarpour
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Irritable bowel syndrome (IBS) is a common bowel disorder which is usually diagnosed through the abdominal pain, fecal irregularities and bloating. Alteration in the intestinal microbial composition is implicating to inflammatory and functional bowel disorders which is recently also noted as an IBS feature. Owing to the potential importance of microbiota implication in both efficiencies of the treatment and prevention of the diseases, we examined the association between the intestinal microbiota and different bowel patterns in a cohort of subjects with IBS and healthy controls. Fresh fecal samples were collected from a total of 50 subjects, 30 of whom met the Rome IV criteria for IBS and 20 Healthy control. Total DNA was extracted and library preparation was conducted following the standard protocol for small whole genome sequencing. The pooled libraries sequenced on an Illumina Nextseq platform with a 2 × 150 paired-end read length and obtained sequences were analyzed using several bioinformatics programs. The majority of sequences obtained in the current study assigned to bacteria. However, our finding highlighted the significant microbial taxa variation among the studied groups. The result, therefore, suggests a significant association of the microbiota with symptoms and bowel characteristics in patients with IBS. These alterations in fecal microbiota could be exploited as a biomarker for IBS or its subtypes and suggest the modification of the microbiota might be integrated into prevention and treatment strategies for IBS.Keywords: irritable bowel syndrome, intestinal microbiota, small whole genome sequencing, fecal samples, Illumina
Procedia PDF Downloads 1461094 Clinical Outcomes of Critically Ill Patients with Sepsis Receiving Extended and Standard Meropenem Infusion in Malaysian Hospitals
Authors: Fahmi Hassan, Noorizan Abdul Aziz, Yahaya Hassan, Hazlinda Abu Hassan
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Sepsis incidence in critical care settings is a major problem in health care. Extended antibiotic infusion is thought to be superior to traditional dosing especially when treating critically ill patients with sepsis. We compared clinical outcomes of critically ill patients with sepsis receiving 30-minute meropenem infusion and three-hour meropenem infusion. A retrospective case-control study was conducted among septic patients treated with meropenem infusion in ICUs of three hospitals. Patients included in the study received either extended or standard meropenem infusion as per the practice of individual settings. Outcomes and clinical data were retrospectively collected from the electronic databases and patients’ files. A total of 108 patients received extended meropenem infusion while another 117 patients received standard meropenem infusion. Patients receiving the extended meropenem infusion were found to have a significantly lower shorter length of hospital and ICU stay. It was also found that among those receiving extended meropenem infusion, 54.7% (64/117) had a reduction of SAPS II score, while only 44% (48/108) of patients receiving standard meropenem infusion had reduced scores. This study will strengthen the evidence in using extended meropenem infusion as a standard practice in critical care settings. As this is the first study of its kind done in Malaysia, it proves that prolonged meropenem infusion may be beneficial to critically ill patients with sepsis. However, randomized clinical trials with large sample size should be carried out in local settings in order to minimize other confounders that may influence with the result of the study.Keywords: antibiotics, beta lactams, critical care, extended infusion, meropenem
Procedia PDF Downloads 3931093 An Experimental Investigation on Banana and Pineapple Natural Fibers Reinforced with Polypropylene Composite by Impact Test and SEM Analysis
Authors: D. Karibasavaraja, Ramesh M.R., Sufiyan Ahmed, Noyonika M.R., Sameeksha A. V., Mamatha J., Samiksha S. Urs
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This research paper gives an overview of the experimental analysis of natural fibers with polymer composite. The whole world is concerned about conserving the environment. Henceforth, the demand for natural and decomposable materials is increasing. The application of natural fibers is widely used in aerospace for manufacturing aircraft bodies, and ship construction in navy fields. Based on the literature review, researchers and scientists are replacing synthetic fibers with natural fibers. The selection of these fibers mainly depends on lightweight, easily available, and economical and has its own physical and chemical properties and many other properties that make them a fine quality fiber. The pineapple fiber has desirable properties of good mechanical strength, high cellulose content, and fiber length. Hybrid composite was prepared using different proportions of pineapple fiber and banana fiber, and their ratios were varied in 90% polypropylene mixed with 5% banana fiber and 5% pineapple fiber, 85% polypropylene mixed with 7.5% banana fiber and 7.5% pineapple fiber and 80% polypropylene mixed with 10% banana fiber and 10% pineapple fiber. By impact experimental analysis, we concluded that the combination of 90% polypropylene and 5% banana fiber and 5% pineapple fiber exhibits a higher toughness value with mechanical strength. We also conducted scanning electron microscopy (SEM) analysis which showed better fiber orientation bonding between the banana and pineapple fibers with polypropylene composites. The main aim of the present research is to evaluate the properties of pineapple fiber and banana fiber reinforced with hybrid polypropylene composites.Keywords: toughness, fracture, impact strength, banana fibers, pineapple fibers, tensile strength, SEM analysis
Procedia PDF Downloads 1381092 Investigating the Use of Seaweed Extracts as Biopesticides
Authors: Emma O’ Keeffe, Helen Hughes, Peter McLoughlin, Shiau Pin Tan, Nick McCarthy
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Biosecurity is emerging as one of the most important issues facing the agricultural and forestry community. This is as a result of increased invasion from new pests and diseases with the main protocol for dealing with these species being the use of synthetic pesticides. However, these chemicals have been shown to exhibit negative effects on the environment. Seaweeds represent a vast untapped resource of bio-molecules with a broad range of biological activities including pesticidal. This project investigated both the antifungal and antibacterial activity of seaweed species against two problematic root rot fungi, Armillaria mellea and Heterobasidion annosum and ten quarantine bacterial plant pathogens including Xanthomonas arboricola, Xanthomonas fragariae, and Erwinia amylovora. Four seaweed species were harvested from the South-East coast of Ireland including brown, red and green varieties. The powdered seaweeds were extracted using four different solvents by liquid extraction. The poisoned food technique was employed to establish the antifungal efficacy, and the standard disc diffusion assay was used to assess the antibacterial properties of the seaweed extracts. It was found that extracts of the green seaweed exhibited antifungal activity against H. annosum, with approximately 50% inhibition compared to the negative control. The protectant activities of the active extracts were evaluated on disks of Picea sitchensis, a plant species sensitive to infection from H. annosum and compared to the standard chemical control product urea. The crude extracts exhibited very similar activity to the 10% and 20% w/v concentrations of urea, demonstrating the ability of seaweed extracts to compete with commercially available products. Antibacterial activity was exhibited by a number of seaweed extracts with the red seaweed illustrating the strongest activity, with a zone of inhibition of 15.83 ± 0.41 mm exhibited against X. arboricola whilst the positive control (10 μg/disk of chloramphenicol) had a zone of 26.5 ± 0.71 mm. These results highlight the potential application of seaweed extracts in the forestry and agricultural industries for use as biopesticides. Further work is now required to identify the bioactive molecules that are responsible for this antifungal and antibacterial activity in the seaweed extracts, including toxicity studies to ensure the extracts are non-toxic to plants and humans.Keywords: antibacterial, antifungal, biopesticides, seaweeds
Procedia PDF Downloads 1621091 Development of Latent Fingerprints on Non-Porous Surfaces Recovered from Fresh and Sea Water
Authors: A. Somaya Madkour, B. Abeer sheta, C. Fatma Badr El Dine, D. Yasser Elwakeel, E. Nermine AbdAllah
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Criminal offenders have a fundamental goal not to leave any traces at the crime scene. Some may suppose that items recovered underwater will have no forensic value, therefore, they try to destroy the traces by throwing items in water. These traces are subjected to the destructive environmental effects. This can represent a challenge for Forensic experts investigating finger marks. Accordingly, the present study was conducted to determine the optimal method for latent fingerprints development on non-porous surfaces submerged in aquatic environments at different time interval. The two factors analyzed in this study were the nature of aquatic environment and length of submerged time. In addition, the quality of developed finger marks depending on the used method was also assessed. Therefore, latent fingerprints were deposited on metallic, plastic and glass objects and submerged in fresh or sea water for one, two, and ten days. After recovery, the items were subjected to cyanoacrylate fuming, black powder and small particle reagent processing and the prints were examined. Each print was evaluated according to fingerprint quality assessment scale. The present study demonstrated that the duration of submersion affects the quality of finger marks; the longer the duration, the worse the quality.The best results of visualization were achieved using cyanoacrylate either in fresh or sea water. This study has also revealed that the exposure to sea water had more destructive influence on the quality of detected finger marks.Keywords: fingerprints, fresh water, sea, non-porous
Procedia PDF Downloads 4461090 Use of Plant Growth Regulators in the Amaryllis Production (Hippeastrum X Hybridum Hort. CV Orange Souvereign)
Authors: Maximiliano K. Pagliarini, Ana Carolina T. Malavolta, Isabela M. Morita, Regina Maria M. Castilho
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Among the ornamental plants, the Amaryllis (Hippeastrum X hybridum Hort.) is one of the most cultivated plants in Brazil because of their large and showy flowers. Thus, the consumer market wants better quality plants or to flourish more in less time. One of the devices that can make such improvements or accelerate the flowering process is the use of growth regulators. The objective of this research was to evaluate the use of different Stimulate® growth regulator doses and its constituents separately in the development and flowering of Hippeastrum X hybridum Hort. Cv Orange Souvereign. The experiment was conducted in a Pad & Fan greenhouse at UNESP, São Paulo State, Brazil from August to October 2014. The bulbs were placed in black vases of 1.2 L filled with commercial substrate and divided into 9 treatments: T1 – 10 mL L-1 of Stimulate®, T2 – 5 mL L-1 of Stimulate®, T3 – 0.5 mg L-1 of gibberellic acid (GA), T4 – 0.25 mg L-1 of GA, T5 – 0.45 mg L-1 of kinetin, T6 – 0.9 mg L-1 of kinetin, T7 – 0.5 mg L-1 of indolbutiric acid (IBA), T8 – 0.25 mg L-1 of IBA and T9 – distilled water (control). All treatments were diluted in water. The used design was completely randomized with six repetitions and two vessels, totalling 12 vessels per treatment. The evaluated characteristics were: number of leaves, length of leaf, number of rods, maximum height of rods, maximum diameter of rods, maximum number of flowers, beginning of flowering, flowering duration, and weight of bulbs. The results showed that the Stimulate® was not efficient in the conducted experiment conditions. However, the best treatment was 0.5 mg L-1 of IBA.Keywords: bulbs, gibberellic acid, indolbutiric acid, kinetin, ornamental plants
Procedia PDF Downloads 5391089 Prenatal Development of Heart and Great Vessels in Buffalo (Bubalus bubalis)
Authors: Anuradha Gupta, Neelam Bansal, Varinder Uppal
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The present investigation was made on 35 Indian buffalo fetuses ranging from 0.9 cm to 104 cm curved crown rump length (CVRL). The gross anatomical study revealed that all structures were developed at 13 cm CVRL (87 days) in group I. At 0.9 cm CVRL (32 days) the heart was unseptated and tubular and was clearly divided into common atrial chamber dorsally and primitive ventricle in 1.2 cm CVRL fetus (34 days). Septum primum appeared at 1.9 cm CVRL (37 days), truncal ridges at 2.5 cm CVRL (39 days) and foramen ovale in 3.0 cm CVRL (42 days) buffalo foetuses. At 7.6 cm CVRL (62 days) endocardial cushions fused to form left and right atrioventricular openings and four chambered heart was formed in 8.7 cm CVRL (66 days). Endocardium and epicardium was thicker in atria as compared to ventricles in all the age groups. Myocardium of atria was thin as compared to ventricles in all the age groups and was loosely arranged. Immature hyaline cartilage was first appeared at base of aorta in 62 cm CVRL (213 days) fetuses. Intercalated discs were seen in group III and aorta, pulmonary artery, coronary artery were well appreciated in 3.2 cm CVRL (43 days). Neutral and acid mucopolysaccharides were comparatively more in atria than ventricles. Basic proteins showed strong reaction in atrium and ventricle, and intense in conduction system. Lipids and phospholipids were more in myocardium and conduction system than endocardium and epicardium. All the histochemical moieties were comparatively more in tunica intima than media and adventitia of all the great vessels of heart.Keywords: buffalo, fetal development, histochemistry, heart
Procedia PDF Downloads 2681088 Effect of Mach Number for Gust-Airfoil Interatcion Noise
Authors: ShuJiang Jiang
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The interaction of turbulence with airfoil is an important noise source in many engineering fields, including helicopters, turbofan, and contra-rotating open rotor engines, where turbulence generated in the wake of upstream blades interacts with the leading edge of downstream blades and produces aerodynamic noise. One approach to study turbulence-airfoil interaction noise is to model the oncoming turbulence as harmonic gusts. A compact noise source produces a dipole-like sound directivity pattern. However, when the acoustic wavelength is much smaller than the airfoil chord length, the airfoil needs to be treated as a non-compact source, and the gust-airfoil interaction becomes more complicated and results in multiple lobes generated in the radiated sound directivity. Capturing the short acoustic wavelength is a challenge for numerical simulations. In this work, simulations are performed for gust-airfoil interaction at different Mach numbers, using a high-fidelity direct Computational AeroAcoustic (CAA) approach based on a spectral/hp element method, verified by a CAA benchmark case. It is found that the squared sound pressure varies approximately as the 5th power of Mach number, which changes slightly with the observer location. This scaling law can give a better sound prediction than the flat-plate theory for thicker airfoils. Besides, another prediction method, based on the flat-plate theory and CAA simulation, has been proposed to give better predictions than the scaling law for thicker airfoils.Keywords: aeroacoustics, gust-airfoil interaction, CFD, CAA
Procedia PDF Downloads 641087 Ankle Arthroscopy: Indications, Patterns of Admissions, Surgical Outcomes, and Associated Complications Among Saudi Patients at King Abdul-Aziz Medical City in Riyadh
Authors: Mohammad Abdullah Almalki
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Background: Despite the frequent usage of ankle arthroscopy, there is limited medical literature regarding its indications, patterns of admissions, surgical outcomes, and associated complicated at Saudi Arabia. Hence, this study would highlight the surgical outcomes of such surgical approach that will assist orthopedic surgeons to detect which surgical procedure needs to be done as well as to help them regarding their diagnostic workups. Methods: At the Orthopedic Division of King Abdul‑Aziz Medical City in Riyadh and through a cross‑sectional design and convenient sampling techniques, the present study had recruited 20 subjects who fulfill the inclusion and exclusion criteria between 2016 and 2018. Data collection was carried out by a questionnaire designed and revised by an expert panel of health professionals. Results: Twenty patients were reviewed (11M and 9F) with an average age of 40.1 ± 12.2. Only 30% of the patients (5M, 1F) have no comorbidity, but 70% of patients (7M, 8F) were having at least one comorbidity. The most common indications were osteochondritis dissecans (n = 7, 35%), ankle fracture without dislocation (n = 4, 20%), and tibiotalar impingement (n = 3, 15%). Patients recorded pain in all cases (100%). The top four symptoms after pain were instability (30%, n = 6), muscle weakness (15%, n = 3) swelling (15%, n = 3), and stiffness (5%, n = 1). Two‑third of cases reached to their full healthy status and toe‑touch weight‑bearing was seen in two patients (10%). Conclusion: Ankle arthroscopy improved the rehabilitation rates in our tertiary care center. In addition, the surgical outcomes are favorable in our hospital since it has a very short length of stay, unexpended surgery, and fewest physiotherapy sessions.Keywords: ankle, arthroscopy, indications, patterns
Procedia PDF Downloads 771086 Acoustic Emission Monitoring of Surface Roughness in Ultra High Precision Grinding of Borosilicate-Crown Glass
Authors: Goodness Onwuka, Khaled Abou-El-Hossein
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The increase in the demand for precision optics, coupled with the absence of much research output in the ultra high precision grinding of precision optics as compared to the ultrahigh precision diamond turning of optical metals has fostered the need for more research in the ultra high precision grinding of an optical lens. Furthermore, the increase in the stringent demands for nanometric surface finishes through lapping, polishing and grinding processes necessary for the use of borosilicate-crown glass in the automotive and optics industries has created the demand to effectively monitor the surface roughness during the production process. Acoustic emission phenomenon has been proven as useful monitoring technique in several manufacturing processes ranging from monitoring of bearing production to tool wear estimation. This paper introduces a rare and unique approach with the application of acoustic emission technique to monitor the surface roughness of borosilicate-crown glass during an ultra high precision grinding process. This research was carried out on a 4-axes Nanoform 250 ultrahigh precision lathe machine using an ultra high precision grinding spindle to machine the flat surface of the borosilicate-crown glass with the tip of the grinding wheel. A careful selection of parameters and design of experiment was implemented using Box-Behnken method to vary the wheel speed, feed rate and depth of cut at three levels with a 3-center point design. Furthermore, the average surface roughness was measured using Taylor Hobson PGI Dimension XL optical profilometer, and an acoustic emission data acquisition device from National Instruments was utilized to acquire the signals while the data acquisition codes were designed with National Instrument LabVIEW software for acquisition at a sampling rate of 2 million samples per second. The results show that the raw and root mean square amplitude values of the acoustic signals increased with a corresponding increase in the measured average surface roughness values for the different parameter combinations. Therefore, this research concludes that acoustic emission monitoring technique is a potential technique for monitoring the surface roughness in the ultra high precision grinding of borosilicate-crown glass.Keywords: acoustic emission, borosilicate-crown glass, surface roughness, ultra high precision grinding
Procedia PDF Downloads 2851085 Structural Performance Evaluation of Concrete Beams Reinforced with Recycled and Virgin Plastic Fibres
Authors: Vighnesh Daas, David B. Tann, Mahmood Datoo
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The incorporation of recycled plastic fibres in concrete as reinforcement is a potential sustainable alternative for replacement of ordinary steel bars. It provides a scope for waste reduction and re-use of plastics in the construction industry on a large scale. Structural use of fibre reinforced concrete is limited to short span members and low reliability classes. In this study, recycled carpet fibres made of 95% polypropylene with length of 45mm were used for experimental investigations. The performance of recycled polypropylene fibres under structural loading has been compared with commercially available virgin fibres at low volume fractions of less than 1%. A series of 100 mm cubes and 125x200x2000 mm beams were used to conduct strength tests in bending and compression to measure the influence of type and volume of fibres on the structural behaviour of fibre reinforced concrete beams. The workability of the concrete mix decreased as a function of fibre content and resulted in a modification of the mix design. The beams failed in a pseudo-ductile manner with an enhanced bending capacity. The specimens showed significant improvement in the post-cracking behaviour and load carrying ability as compared to conventional reinforced concrete members. This was associated to the binding properties of the fibres in the concrete matrix. With the inclusion of fibres at low volumes of 0-0.5%, there was reduction in crack sizes and deflection. This study indicates that the inclusion of recycled polypropylene fibres at low volumes augments the structural behaviour of concrete as compared to conventional reinforced concrete as well as virgin fibre reinforced concrete.Keywords: fibre reinforced concrete, polypropylene, recycled, strength
Procedia PDF Downloads 2371084 Atmospheric Dispersion Modeling for a Hypothetical Accidental Release from the 3 MW TRIGA Research Reactor of Bangladesh
Authors: G. R. Khan, Sadia Mahjabin, A. S. Mollah, M. R. Mawla
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Atmospheric dispersion modeling is significant for any nuclear facilities in the country to predict the impact of radiological doses on environment as well as human health. That is why to ensure safety of workers and population at plant site; Atmospheric dispersion modeling and radiation dose calculations were carried out for a hypothetical accidental release of airborne radionuclide from the 3 MW TRIGA research reactor of Savar, Bangladesh. It is designed with reactor core which consists of 100 fuel elements(1.82245 cm in diameter and 38.1 cm in length), arranged in an annular corefor steady-state and square wave power level of 3 MW (thermal) and for pulsing with maximum power level of 860MWth.The fuel is in the form of a uniform mixture of 20% uranium and 80% zirconium hydride. Total effective doses (TEDs) to the public at various downwind distances were evaluated with a health physics computer code “HotSpot” developed by Lawrence Livermore National Laboratory, USA. The doses were estimated at different Pasquill stability classes (categories A-F) with site-specific averaged meteorological conditions. The meteorological data, such as, average wind speed, frequency distribution of wind direction, etc. have also been analyzed based on the data collected near the reactor site. The results of effective doses obtained remain within the recommended maximum effective dose.Keywords: accidental release, dispersion modeling, total effective dose, TRIGA
Procedia PDF Downloads 1271083 Improving Indoor Air Quality by Increasing Bio-Based Negative Air Ion Release
Authors: Shuye Jiang, Ali Ma, Srinivasan Ramachandran
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Indoor air quality could be improved through traditional air purifiers. However, they may not be environmental products. Here, a bio-based method was employed to improve indoor air quality by increasing negative air ion (NAI) release from ornamental plants. A total of 60 plant species has been screened by evaluating their ability to release NAIs, from which four candidates were selected to further study. All of them are from the Dracaena or fabids clade. These four candidates were then subjected to survey their ability to reduce the concentration of particulate matter with diameter of 2.5 or 10 microns (PM2.5 and PM10) in the growth chamber. High concentrations of PM2.5 and PM10 were artificially generated by burning a stick of incense for 2 minutes in the closed growth chamber (80cm length × 80cm width × 80cm height), in which the PM2.5 and PM10 concentration were generally around 500 µg/m3 and 1500 µg/m3, respectively. Both PM2.5 and PM10 were naturally reduced to 410 and 670, respectively after two hours in case that no plants were placed inside the chamber. Interestingly, these two sizes of particulars were reduced to 170 µg/m3 and 210 µg/m3, respectively after two hours when plants were placed to the chamber. It took 4 hours for the plants to reduce particular concentration to acceptable level at less than 55 µg/m3 for both PM2.5 and PM10, respectively. However, the PM2.5 and PM10 concentration were still above 200 µg/m3 and 300 µg/m3, respectively after 4 hours in the growth chamber without any plants. These results suggest the contribution of plants to the particulate deposition. However, all of these data are preliminary and the results may be updated by further studies. In addition, the roles of plants in absorbing indoor formaldehyde have also been explored and their absorbing ability is being improved by optimizing their growth conditions and treating with various exogenous agents. Thus, our preliminary studies provide an alternative strategy to improve indoor air quality.Keywords: bio-based method, indoor air, negative air ion, particulate matter
Procedia PDF Downloads 1561082 Genome-Wide Analysis of Long Terminal Repeat (LTR) Retrotransposons in Rabbit (Oryctolagus cuniculus)
Authors: Zeeshan Khan, Faisal Nouroz, Shumaila Noureen
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European or common rabbit (Oryctolagus cuniculus) belongs to class Mammalia, order Lagomorpha of family Leporidae. They are distributed worldwide and are native to Europe (France, Spain and Portugal) and Africa (Morocco and Algeria). LTR retrotransposons are major Class I mobile genetic elements of eukaryotic genomes and play a crucial role in genome expansion, evolution and diversification. They were mostly annotated in various genomes by conventional approaches of homology searches, which restricted the annotation of novel elements. Present work involved de novo identification of LTR retrotransposons by LTR_FINDER in haploid genome of rabbit (2247.74 Mb) distributed in 22 chromosomes, of which 7,933 putative full-length or partial copies were identified containing 69.38 Mb of elements, accounting 3.08% of the genome. Highest copy numbers (731) were found on chromosome 7, followed by chromosome 12 (705), while the lowest copy numbers (27) were detected in chromosome 19 with no elements identified from chromosome 21 due to partially sequenced chromosome, unidentified nucleotides (N) and repeated simple sequence repeats (SSRs). The identified elements ranged in sizes from 1.2 - 25.8 Kb with average sizes between 2-10 Kb. Highest percentage (4.77%) of elements was found in chromosome 15, while lowest (0.55%) in chromosome 19. The most frequent tRNA type was Arginine present in majority of the elements. Based on gained results, it was estimated that rabbit exhibits 15,866 copies having 137.73 Mb of elements accounting 6.16% of diploid genome (44 chromosomes). Further molecular analyses will be helpful in chromosomal localization and distribution of these elements on chromosomes.Keywords: rabbit, LTR retrotransposons, genome, chromosome
Procedia PDF Downloads 1381081 Social Media Marketing and Blog Usage in Business Schools: An Exploratory Study
Authors: Grzegorz Mazurek, Michal Kucia
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The following study of a preliminary character, presents a first step of multifaceted study on the usage of social media in HEIs. It examines a significance, potential, and managerial implications of social media marketing and blogs usage in HEIs – namely in the sphere of business schools. Social media – particularly: blogging and virtual platforms such as Facebook, Twitter or Instagram have been covered at length in publications of both theoretical and practical nature as of late. Still, the amount of information related to the framework of application of social media in HEIs is rather limited. A pre-designed observation matrix has been used to collect primary data found at websites of different HEIs and to include blog observations. Additionally, a pilot study based on on-line questionnaires with marketing officers of HEI schools has been conducted. The main aim of the study was to identify and elaborate on matters like the scope of social media usage (and blogs in particular) in practice, recognition of the functions fulfilled by social media and blogs, or the anticipated potential of social media for HEIs. The study reveals that the majority of business schools highly ranked in Financial Times rankings use social media and interactive functionalities of their web sites, however, mostly for promotional reasons, and they are targeted at new students. The usage of blogs, though, is not so common and in most cases, blogs are independent platforms, not managed but supported by organizations. Managers and specialists point to lack of resources, insufficient users’ engagement and lack of strategic approach to social media as the main reasons of not advancing in the usage of blogs and social media platforms.Keywords: blogs, social media marketing, higher education institutions, business schools, value co-creation
Procedia PDF Downloads 2531080 Problems in Computational Phylogenetics: The Germano-Italo-Celtic Clade
Authors: Laura Mclean
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A recurring point of interest in computational phylogenetic analysis of Indo-European family trees is the inference of a Germano-Italo-Celtic clade in some versions of the trees produced. The presence of this clade in the models is intriguing as there is little evidence for innovations shared among Germanic, Italic, and Celtic, the evidence generally used in the traditional method to construct a subgroup. One source of this unexpected outcome could be the input to the models. The datasets in the various models used so far, for the most part, take as their basis the Swadesh list, a list compiled by Morris Swadesh and then revised several times, containing up to 207 words that he believed were resistant to change among languages. The judgments made by Swadesh for this list, however, were subjective and based on his intuition rather than rigorous analysis. Some scholars used the Swadesh 200 list as the basis for their Indo-European dataset and made cognacy judgements for each of the words on the list. Another dataset is largely based on the Swadesh 207 list as well although the authors include additional lexical and non-lexical data, and they implement ‘split coding’ to deal with cases of polymorphic characters. A different team of scholars uses a different dataset, IECoR, which combines several different lists, one of which is the Swadesh 200 list. In fact, the Swadesh list is used in some form in every study surveyed and each dataset has three words that, when they are coded as cognates, seemingly contribute to the inference of a Germano-Italo-Celtic clade which could happen due to these clades sharing three words among only themselves. These three words are ‘fish’, ‘flower’, and ‘man’ (in the case of ‘man’, one dataset includes Lithuanian in the cognacy coding and removes the word ‘man’ from the screened data). This collection of cognates shared among Germanic, Italic, and Celtic that were deemed important enough to be included on the Swadesh list, without the ability to account for possible reasons for shared cognates that are not shared innovations, gives an impression of affinity between the Germanic, Celtic, and Italic branches without adequate methodological support. However, by changing how cognacy is defined (ie. root cognates, borrowings vs inherited cognates etc.), we will be able to identify whether these three cognates are significant enough to infer a clade for Germanic, Celtic, and Italic. This paper examines the question of what definition of cognacy should be used for phylogenetic datasets by examining the Germano-Italo-Celtic clade as a case study and offers insights into the reconstruction of a Germano-Italo-Celtic clade.Keywords: historical, computational, Italo-Celtic, Germanic
Procedia PDF Downloads 411079 Oral Hygiene Behaviors among Pregnant Women with Diabetes Who Attend Primary Health Care Centers at Baghdad City
Authors: Zena F. Mushtaq, Iqbal M. Abbas
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Background: Diabetes mellitus during pregnancy is one of the major medical and social problems with increasing prevalence in last decades and may lead to more vulnerable to dental problems and increased risk for periodontal diseases. Objectives: To assess oral hygiene behaviors among pregnant women with diabetes who attended primary health care centers and find out the relationship between oral hygiene behaviors and studied variables. Methodology: A cross sectional design was conducted from 7 July to 30 September 2014 on non probability (convenient sample) of 150 pregnant women with diabetes was selected from twelve Primary Health Care Centers at Baghdad city. Questionnaire format is tool for data collection which had designed and consisted of three main parts including: socio demographic, reproductive characteristics and items of oral hygiene behaviors among pregnant women with diabetes. Reliability of the questionnaire was determined through internal consistency of correlation coefficient (R= 0.940) and validity of content was determined through reviewing it by (12) experts in different specialties and was determined through pilot study. Descriptive and inferential statistics were used to analyze collected data. Result: Result of study revealed that (35.3%) of study sample was (35-39) years old with mean and SD is (X & SD = 33.57 ± 5.54) years, and (34.7%) of the study sample was graduated from primary school and less, half of the study sample was government employment and self employed, (42.7%) of the study sample had moderate socioeconomic status, the highest percentage (70.0%) of the study sample was nonsmokers, The result indicates that oral hygiene behaviors have moderate mean score in all items. There are no statistical significant association between oral hygiene domain and studied variables. Conclusions: All items related to health behavior concerning oral hygiene is in moderate mean of score, which may expose pregnant women with diabetes to high risk of periodontal diseases. Recommendations: Dental care provider should perform a dental examination at least every three months for each pregnant woman with diabetes, explanation of the effect of DM on periodontal health, oral hygiene instruction, oral prophylaxis, professional cleaning and treatment of periodontal diseases(scaling and root planing) when needed.Keywords: diabetes, health behavior, pregnant women, oral hygiene
Procedia PDF Downloads 2751078 Geochemical Characteristics and Chemical Toxicity: Appraisal of Groundwater Uranium With Other Geogenic Contaminants in Various Districts of Punjab, India
Authors: Tanu Sharma, Bikramjit Singh Bajwa, Inderpreet Kaur
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Monitoring of groundwater in Tarn-Taran, Bathinda, Faridkot and Mansa districts of Punjab state, India is essential where this freshwater resource is being over-exploited causing quality deterioration, groundwater depletion and posing serious threats to residents. The present integrated study was done to appraise quality and suitability of groundwater for drinking/irrigation purposes, hydro-geochemical characteristics, source identification and associated health risks. In the present study, groundwater of various districts of Punjab state was found to be heavily contaminated with As followed by U, thus posing high cancerous risks to local residents via ingestion, along with minor contamination of Fe, Mn, Pb and F−. Most health concerns in the study region were due to the elevated concentrations of arsenic in groundwater with average values of 130 µg L-1, 176 µg L-1, 272 µg L-1 and 651 µg L-1 in Tarn-Taran, Bathinda, Faridkot and Mansa districts, respectively, which is quite high as compared to the safe limit as recommended by BIS i.e. 10 µg L-1. In Tarn-Taran, Bathinda, Faridkot and Mansa districts, average uranium contents were found to be 37 µg L-1, 88 µg L-1, 61 µg L-1 and 104 µg L-1, with 51 %, 74 %, 61 % and 71 % samples, respectively, being above the WHO limit of 30 µg L-1 in groundwater. Further, the quality indices showed that groundwater of study region is suited for irrigation but not appropriate for drinking purposes. Hydro-geochemical studies revealed that most of the collected groundwater samples belonged to Ca2+ - Mg2+ - HCO3- type showing dominance of MgCO3 type which indicates the presence of temporary hardness in groundwater. Rock-water reactions and reverse ion exchange were the predominant factors for controlling hydro-geochemistry in the study region. Dissolution of silicate minerals caused the dominance of Na+ ions in the aquifers of study region. Multivariate statistics revealed that along with geogenic sources, contribution of anthropogenic activities such as injudicious application of agrochemicals and domestic waste discharge was also very significant. The results obtained abolished the myth that uranium is only root cause for large number of cancer patients in study region as arsenic and mercury were also present in groundwater at levels that were of health concern to groundwater.Keywords: uranium, trace elements, multivariate data analysis, risk assessment
Procedia PDF Downloads 661077 Design Optimization of Chevron Nozzles for Jet Noise Reduction
Authors: E. Manikandan, C. Chilambarasan, M. Sulthan Ariff Rahman, S. Kanagaraj, V. R. Sanal Kumar
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The noise regulations around the major airports and rocket launching stations due to the environmental concern have made jet noise a crucial problem in the present day aero-acoustics research. The three main acoustic sources in jet nozzles are aerodynamics noise, noise from craft systems and engine and mechanical noise. Note that the majority of engine noise is due to the jet noise coming out from the exhaust nozzle. The previous studies reveal that the potential of chevron nozzles for aircraft engines noise reduction is promising owing to the fact that the jet noise continues to be the dominant noise component, especially during take-off. In this paper parametric analytical studies have been carried out for optimizing the number of chevron lobes, the lobe length and tip shape, and the level of penetration of the chevrons into the flow over a variety of flow conditions for various aerospace applications. The numerical studies have been carried out using a validated steady 3D density based, SST k-ω turbulence model with enhanced wall functions. In the numerical study, a fully implicit finite volume scheme of the compressible, Navier–Stokes equations is employed. We inferred that the geometry optimization of an environmental friendly chevron nozzle with a suitable number of chevron lobes with aerodynamically efficient tip contours for facilitating silent exit flow will enable a commendable sound reduction without much thrust penalty while comparing with the conventional supersonic nozzles with same area ratio.Keywords: chevron nozzle, jet acoustic level, jet noise suppression, shape optimization of chevron nozzles
Procedia PDF Downloads 3061076 Place Attachment and Residential Satisfaction in Old Residential Buildings: A Case of Pune City
Authors: Vaishali Anagal, Vasudha Gokhale, Sharvey Dhongde
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Old buildings have significance in many aspects. The manifold significance may include historic, architectural and cultural aspects. In a cultural city like Pune, India, numerous residential buildings exist in the core city whose age may range between 60-100 years. These represent the city’s history and culture. Most of them are still in use as residential buildings with adaptations in various degrees. Some of these buildings are enlisted as ‘Heritage Buildings’ by local municipal authority. However, there are number of buildings that have heritage value although they are not enlisted as heritage sites. A lot of these buildings have already been pulled down for several reasons such as end of technical life, inadequacy for users, increasing floor area ratios, inflating land prices and changing lifestyles etc. Literature suggest that place attachment and residential satisfaction are positively related. It also indicates that length of residency is positively correlated with the place attachment. Residential satisfaction is associated with number of factors including socio demographic characteristics of users, housing characteristics, neighborhood characteristics and behavioral characteristics. This research paper poses an inquiry about the dynamics of co-relation between place attachment and residential satisfaction in case of old residential buildings. The motive of this enquiry is to examine if place attachment can serve as a strong ground for restoration of these old buildings and evade the devastation of emblems of cultural heritage of the city. The methodology includes questionnaire survey of users as well as a qualitative assessment regarding place attachment and residential satisfaction. About 20 residential buildings in the core city of Pune are selected for this purpose. The results of survey are analyzed and conclusions are drawn.Keywords: place attachment, residential satisfaction, old residential buildings, housing characteristics, cultural heritage
Procedia PDF Downloads 2341075 Contribution of Automated Early Warning Score Usage to Patient Safety
Authors: Phang Moon Leng
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Automated Early Warning Scores is a newly developed clinical decision tool that is used to streamline and improve the process of obtaining a patient’s vital signs so a clinical decision can be made at an earlier stage to prevent the patient from further deterioration. This technology provides immediate update on the score and clinical decision to be taken based on the outcome. This paper aims to study the use of an automated early warning score system on whether the technology has assisted the hospital in early detection and escalation of clinical condition and improve patient outcome. The hospital adopted the Modified Early Warning Scores (MEWS) Scoring System and MEWS Clinical Response into Philips IntelliVue Guardian Automated Early Warning Score equipment and studied whether the process has been leaned, whether the use of technology improved the usage & experience of the nurses, and whether the technology has improved patient care and outcome. It was found the steps required to obtain vital signs has been significantly reduced and is used more frequently to obtain patient vital signs. The number of deaths, and length of stay has significantly decreased as clinical decisions can be made and escalated more quickly with the Automated EWS. The automated early warning score equipment has helped improve work efficiency by removing the need for documenting into patient’s EMR. The technology streamlines clinical decision-making and allows faster care and intervention to be carried out and improves overall patient outcome which translates to better care for patient.Keywords: automated early warning score, clinical quality and safety, patient safety, medical technology
Procedia PDF Downloads 1711074 Structural Analysis and Modelling in an Evolving Iron Ore Operation
Authors: Sameh Shahin, Nannang Arrys
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Optimizing pit slope stability and reducing strip ratio of a mining operation are two key tasks in geotechnical engineering. With a growing demand for minerals and an increasing cost associated with extraction, companies are constantly re-evaluating the viability of mineral deposits and challenging their geological understanding. Within Rio Tinto Iron Ore, the Structural Geology (SG) team investigate and collect critical data, such as point based orientations, mapping and geological inferences from adjacent pits to re-model deposits where previous interpretations have failed to account for structurally controlled slope failures. Utilizing innovative data collection methods and data-driven investigation, SG aims to address the root causes of slope instability. Committing to a resource grid drill campaign as the primary source of data collection will often bias data collection to a specific orientation and significantly reduce the capability to identify and qualify complexity. Consequently, these limitations make it difficult to construct a realistic and coherent structural model that identifies adverse structural domains. Without the consideration of complexity and the capability of capturing these structural domains, mining operations run the risk of inadequately designed slopes that may fail and potentially harm people. Regional structural trends have been considered in conjunction with surface and in-pit mapping data to model multi-batter fold structures that were absent from previous iterations of the structural model. The risk is evident in newly identified dip-slope and rock-mass controlled sectors of the geotechnical design rather than a ubiquitous dip-slope sector across the pit. The reward is two-fold: 1) providing sectors of rock-mass controlled design in previously interpreted structurally controlled domains and 2) the opportunity to optimize the slope angle for mineral recovery and reduced strip ratio. Furthermore, a resulting high confidence model with structures and geometries that can account for historic slope instabilities in structurally controlled domains where design assumptions failed.Keywords: structural geology, geotechnical design, optimization, slope stability, risk mitigation
Procedia PDF Downloads 311073 Character Bioacoustics White-Rumped Shama Copsychus malabaricus as a Cage-Bird
Authors: Novia Liza Rahmawaty, Wilson Novarino, Muhammad Nazri Janra
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Indonesian people love to keep songbird in cage to be competed, such as White-rumped Shama (Copsychus malabaricus). Each individual White-rumped Shama will be pitted their song and try to imitate the rhythm of the enemy with its songs. This study was conducted to see the natural song characters of White-rumped Shama and song character from birds that had been trained and comparison in three different places in West Sumatra. Individuals were recorded totaling 30 individuals in three areas in West Sumatra namely Padang, Solok and Pariaman and sound recordings of White-rumped Shama in nature were taken in HBW and Xenocanto website. Research has done conducted from June to October 2016 at place group practice of birdsongs and recorded at 16:00 to 18:00 pm. These voices were analyzed by Avisoft SAS-Lab Lite inform of oscillogram and sonogram. Measured parameters included: the length of voice, repertoire size, number of syllable type, syllable repertoire, and song repertoire. The results showed that repertoire composition of White-rumped Shama in nature less than the sound which was trained and has repeat songs composed by the same type of repertoire composition. Comparison of song character White-rumped Shama in three different places in West Sumatra, those birds in Solok had the best quality of voice or song than Padang and Pariaman. It showed by higher repertoire composition in Solok.Keywords: repertoire composition, song characters, songbird, white-rumped shama
Procedia PDF Downloads 3211072 Attitude to the Types of Organizational Change
Authors: O. Y. Yurieva, O. V. Yurieva, O. V. Kiselkina, A. V. Kamaseva
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Since the early 2000s, there are some innovative changes in the civil service in Russia due to administrative reform. Perspectives of the reform of the civil service include a fundamental change in the personnel component, increasing the level of professionalism of officials, increasing their capacity for self-organization and self-regulation. In order to achieve this, the civil service must be able to continuously change. Organizational changes have long become the subject of scientific understanding; problems of research in the field of organizational change is presented by topics focused on the study of the methodological aspects of the implementation of the changes, the specifics of changes in different types of organizations (business, government, and so on), design changes in the organization, including based on the change in organizational culture. In this case, the organizational changes in the civil service are the least studied areas; research of problems of its transformation is carried out in fragments. According to the theory of resistance of Herbert Simon, the root of the opposition and rejection of change is in the person who will resist any change, if it threatens to undermine the degree of satisfaction as a member of the organization (regardless of the reasons for this change). Thus, the condition for successful adaptation to changes in the organization is the ability of its staff to perceive innovation. As part of the problem, the study sought to identify the innovation civil servants, to determine readiness for the development of proposals for the implementation of organizational change in the public service. To identify the relationship to organizational changes case study carried out by the method of "Attitudes to organizational change" of I. Motovilina, which allowed predicting the type of resistance to changes, to reveal the contradictions and hidden results. The advantage of the method of I. Motovilina is its brevity, simplicity, the analysis of the responses to each question, the use of "overlapping" issues potentially conflicting factors. Based on the study made by the authors, it was found that respondents have a positive attitude to change more local than those that take place in reality, such as "increase opportunities for professional growth", "increase the requirements for the level of professionalism of", "the emergence of possible manifestations initiatives from below". Implemented by the authors diagnostics related to organizational changes in the public service showed the presence of specific problem areas, with roots in the lack of understanding of the importance of innovation personnel in the process of bureaucratization of innovation in public service organizations.Keywords: innovative changes, self-organization, self-regulation, civil service
Procedia PDF Downloads 4481071 Factors of the Community Leaders' and Citizens' Way of Life Based on the Sufficient Economy in Vientiane, Lao People's Democratic Republic
Authors: Phusit Phukamchanoad
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This research aims to analyze the fundamental factors of the community leader and citizens behind the self-sufficient living in Vientiane, Lao People's Democratic Republic. The data were collected by asking 400 citizens to fill out the questionnaires and having in-depth interviews with 30 community leaders. It was found that the factors which had influenced the practice of the sufficiency economy philosophy were age, occupation, length of time living in Vientiane, education, monthly income, monthly expense, and the sufficiency economy philosophy training. The people who had been trained could practice the sufficiency economy philosophy better at both individual and household level than the people who had not been trained. The people who were older than 36 years old had practiced the sufficiency economy philosophy more than the people who were younger than 35 years old. The people who worked in state-owned enterprises, private businesses, and government officials: teachers, police officers, soldiers, and ministers applied the sufficiency economy philosophy more than the samples who were students. The people who lived in Vientiane for more than 31 years applied the sufficiency economy philosophy more than the samples who lived in Vientiane for not more than 30 years. The people whose incomes exceeded 20,001 baht applied the sufficiency economy philosophy more than the people whose incomes did not exceed 20,000 baht. Both community leaders and citizens had a good relationship with their families and community. The community members supported each other during tough times. There were regular meetings in the community. There was unity within the families. The time to build a bond in the family was the time when everyone was eating together. Also, most community leaders and citizens had at least two jobs per one person.Keywords: sufficiency economy philosophy, fundamental factors, way of life, Vientiane Lao PDR
Procedia PDF Downloads 1361070 Condensation Heat Transfer and Pressure Drop of R-134a Flowing inside Dimpled Tubes
Authors: Kanit Aroonrat, Somchai Wongwises
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A heat exchanger is one of the vital parts in a wide variety of applications. The tube with surface modification is generally referred to as an enhanced tube. With this, the thermal performance of the heat exchanger is improved. A dimpled tube is one of many kinds of enhanced tube. The heat transfer and pressure drop of two-phase flow inside dimpled tubes have received little attention in the literature, despite of having an important role in the development of refrigeration and air conditioning systems. As a result, the main aim of this study is to investigate the condensation heat transfer and pressure drop of refrigerant-134a flowing inside dimpled tubes. The test section is a counter-flow double-tube heat exchanger, which the refrigerant flows in the inner tube and water flows in the annulus. The inner tubes are one smooth tube and three dimpled tubes with different helical pitches. All test tubes are made from copper with an inside diameter of 8.1 mm and length of 1500 mm. The experiments are conducted over mass fluxes ranging from 300 to 500 kg/m²s, heat flux ranging from 10 to 20 kW/m², and condensing temperature ranging from 40 to 50 ˚C. The results show that all dimpled tubes provide higher heat transfer coefficient and frictional pressure drop compared to the smooth tube. In addition, the heat transfer coefficient and frictional pressure drop increase with decreasing of helical pitch. It can be observed that the dimpled tube with lowest helical pitch yields the heat transfer enhancement in the range of 60-89% with the frictional pressure drop increase of 289-674% in comparison to the smooth tube.Keywords: condensation, dimpled tube, heat transfer, pressure drop
Procedia PDF Downloads 2071069 Examination of State of Repair of Buildings in Private Housing Estates in Enugu Metropolis, Enugu State Nigeria
Authors: Umeora Chukwunonso Obiefuna
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The private sector in housing provision continually take steps towards addressing part of the problem of cushioning the effect of the housing shortage in Nigeria by establishing housing estates since the government alone cannot provide housing for everyone. This research examined and reported findings from research conducted on the state of repair of buildings in private housing estates in Enugu metropolis, Enugu state Nigeria. The objectives of the study were to examine the physical conditions of the building fabrics and appraise the performance of infrastructural services provided in the buildings. The questionnaire was used as a research instrument to elicit data from respondents. Stratified sampling of the estates based on building type was adopted as a sampling method for this study. Findings from the research show that the state of repair of most buildings require minor repairs to make them fit for habitation and sound to ensure the well-being of the residents. In addition, four independent variables from the nine independent variables investigated significantly explained residual variation in the dependent variable - state of repair of the buildings in the study area. These variables are: Average Monthly Income of Residents (AMIR), Length of Stay of the Residents in the estates (LSY), Type of Wall Finishes on the buildings (TWF), and Time Taken to Respond to Resident’s complaints by the estate managers (TTRC). With this, the linear model was established for predicting the state of repair of buildings in private housing estates in the study area. This would assist in identifying variables that are lucid in predicting the state of repair of the buildings.Keywords: building, housing estate, private, repair
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