Search results for: analysis of personal documents
5300 Impact of Agroforestry Practices on Biodiversity Management and Livelihoods of Communities Adjacent Magamba Nature Reserve(MNR), Tanzania
Authors: P. J. Kagosi, M. Mndolwa, E. Japhate
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The study was conducted to communities adjacent MNR, Lushoto district, Tanzania. The MNR is one of the nine nature reserves in the Eastern Arc Mountains of Tanzania with an area of 8,700ha with high biological diversity. However, biodiversity in MNR have been threatened by increasing human activities for livelihood in 1970s. The AF systems in the study area was practised since 1980s however, no study was conducted on AF impacts. This paper presents the influence of AF on livelihood of communities adjacent MNR and biodiversity conservation. Qualitative and quantitative data were collected using socio-economic survey and botanical surveys. Data were analysed using Statistical Packages for Social Sciences and content analysis. The study found that in 1970s free livestock grazing caused considerable surface runoff, soil erosion and reduction of crop production. Since 1980s, the study area received various interventions based on the land conservations and improved livelihood through practising AF systems. It was further found that the AF farming improved crop productivity, reduced soil erosion, increased firewood (80.2%) and other forest products availability and AF encouraged community members practicing indoor livestock keeping.The dominant agroforestry tree found in the study area is grevillea reported by 74.1% of respondents planting an average of 40 trees. The study found that the AF reduced pressure to MNR as forest products and fodders were obtained from community's farms in turn, currently water flow from MNR has been increased. Thus AF products support livelihood needs and conserve biodiversity. The study recommends continuity education on new AF technology packages.Keywords: impact of agroforestry, biodiversity management, communities’ livelihoods, Magamba nature reserve
Procedia PDF Downloads 3555299 Use of the Budyko Framework to Estimate the Virtual Water Content in Shijiazhuang Plain, North China
Authors: Enze Zhang
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One of the most challenging steps in implementing virtual water content (VWC) analysis of crops is to get properly the total volume of consumptive water use (CWU) and, therefore, the choice of a reliable crop CWU estimation method. In practice, lots of previous researches obtaining CWU of crops follow a classical procedure for calculating crop evapotranspiration which is determined by multiplying reference evapotranspiration by appropriate coefficient, such as crop coefficient and water stress coefficients. However, this manner of calculation requires lots of field experimental data at point scale and more seriously, when current growing conditions differ from the standard conditions, may easily produce deviation between the calculated CWU and the actual CWU. Since evapotranspiration caused by crop planting always plays a vital role in surface water-energy balance in an agricultural region, this study decided to alternatively estimates crop evapotranspiration by Budyko framework. After brief introduce the development process of Budyko framework. We choose a modified Budyko framework under unsteady-state to better evaluated the actual CWU and apply it in an agricultural irrigation area in North China Plain which rely on underground water for irrigation. With the agricultural statistic data, this calculated CWU was further converted into VWC and its subdivision of crops at the annual scale. Results show that all the average values of VWC, VWC_blue and VWC_green show a downward trend with increased agricultural production and improved acreage. By comparison with the previous research, VWC calculated by Budyko framework agree well with part of the previous research and for some other research the value is greater. Our research also suggests that this methodology and findings may be reliable and convenient for investigation of virtual water throughout various agriculture regions of the world.Keywords: virtual water content, Budyko framework, consumptive water use, crop evapotranspiration
Procedia PDF Downloads 3335298 Effect of Garlic Extract on Growth Performance and Immune System of Broiler
Authors: Merry Muspita Dyah Utami
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The positive effect of garlic extract have been reported by many studies. It has antibiotical potential, antibacterial, antiviral, antiparasitic, antifungal, and growth promoting. Supplementary garlic for broilers could mediate in getting the bioactive compounds in garlic. The avian bursa must be essential for antibody-mediated immunity. The size of bursa of fabricius must be some sort of endocrine or lymphoid gland associated with growth and sexual development. The research was conducted to evaluate the effects of garlic extract on growth performance and immune system of broiler. Seventy-two day old chick were equally divided into four group, three replication and six chicks each. Group I was control without garlic extract, then garlic extraxt was administrated to the experimental group II, III and IV (2, 4, 6% in ration). The experiment was conducted for three weeks period from day old chick to 21 days. Body weight of broiler were determined at day 1 and 21, feed intake was determined at the same period, feed conversion ratio was calculated accordingly. At 21 day age, four birds per replicate were slaughtered , bursa was collected, weight and calculated as a percentage of live body weight. Mortality was recorded as it occurred and was used to ajust the total number of broiler to determine the total feed intake and feed conversion rasio. Data were expressed as the mean was compare by one way analysis of variance (Anova) follow by Duncan Test, which used to identify differences between groups. A value of P<0.05 was accepted as significance. The body weight, feed conversion rasio, and the weight of bursa of fabricius showed a significant differences, but feed consumption and the percentage of bursa of live body weight were not significantly different (P > 0.05) influenced by dietary treatments. The results of this research, garlic extract has a potential role as natural growth promoter and immunomodulatory system in broiler.Keywords: garlic extract, growth, immunity, broiler
Procedia PDF Downloads 3305297 Constrains to Financial Engineering for Liquidity Management: A Multiple Case Study of Islamic Banks
Authors: Sadia Bibi, Karim Ullah
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Islamic banks have excess liquidity, which needs proper management to earn a high rate of return on them to remain competitive. However, they lack assets-backed avenues and rely on a few sukuks, which led them to liquidity management issues. Financial engineering comes forward to innovate and develop instruments for the requisite financial problem. Still, they face many challenges, explored in the context of liquidity management in Islamic banks. The rigorous literature review shows that Shariah compliance, competition from the conventional banks, lack of sufficient instruments, derivatives are still not accepted as legitimate products, the inter-bank market being less developed, and no possibility of lender of last resort is the six significant constraints to financial engineering for liquidity management of Islamic banks. To further explore the problem, a multiple case study strategy is used to extend and develop the theory with the philosophical stance of social constructivism. Narrative in-depth interviews over the telephone are conducted with key personnel at treasury departments of selected banks. Data is segregated and displayed using NVivo 11 software, and the thematic analysis approach identifies themes related to the constraints. The exploration of further constraints to financial engineering for liquidity management of Islamic banks achieves the research aim. The theory is further developed by the addition of three more constraints to the theoretical framework, which are i) lack of skilled human resources, ii) lack of unified vision, and iii) lack of government support to the Islamic banks. These study findings are fruitful for the use of the government, regulatory authorities of the banking sector, the State Bank of Pakistan (Central Bank), and the product design & development division of Islamic banks to make the financial engineering process feasible and resolve liquidity management issues of Islamic banks.Keywords: financial engineering, liquidity management, Islamic banks, shariah compliance
Procedia PDF Downloads 845296 An Exploration of the Association Between the Physical Activity and Academic Performance in Internship Medical Students
Authors: Ali Ashraf, Ghazaleh Aghaee, Sedigheh Samimian, Mohaya Farzin
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Objectives: Previous studies have indicated the positive effect of physical activity and sports on different aspects of health, such as muscle endurance and sleep cycle. However, in university students, particularly medical students, who have limited time and a stressful lifestyle, there have been limited studies exploring this matter with proven statistical results. In this regard, this study aims to find out how regular physical activity can influence the academic performance of medical students during their internship period. Methods: This was a descriptive-analytical study. Overall, 160 medical students (including 80 women and 88 men) voluntarily participated in the study. The Baecke Physical Activity Questionnaire was applied to determine the student’s physical activity levels. The student's academic performance was determined based on their total average academic scores. The data were analyzed in SPSS version 16 software using the independent t-test, Pearson correlation, and linear regression. Results: The average age of the students was 26.0±1.5 years. Eighty-eight students (52.4%) were male, and 142 (84.5%) were single. The student's mean total average academic score was 16.2±1.2, and their average physical activity score was 8.3±1.1. The student's average academic score was not associated with their gender (P=0.427), marital status (P=0.645), and age (P=0.320). However, married students had a significantly lower physical activity level compared to single students (P=0.020). The results indicated a significant positive correlation between student's physical activity levels and average academic scores (r=+0.410 and P<0.001). This correlation was independent of the student’s age, gender, and marital status based on the regression analysis. Conclusion: The results of the current study suggested that the physical activity level in medical students was low to moderate in most cases, and there was a significant direct relationship between student’s physical activity level and academic performance, independent of age, gender, and marital status.Keywords: exercise, education, physical activity, academic performance
Procedia PDF Downloads 475295 Planning for Enviromental and Social Sustainability in Coastal Areas: A Case of Alappad
Authors: K. Vrinda
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Coastal ecosystems across the world are facing a lot of challenges due to natural phenomena as well as from uncontrolled human interventions. Here, Alappad, a coastal island situated in Kerala, India is undergoing significant damage and is gradually losing its environmental and social sustainability. The area is blessed with very rare and precious black mineral sand deposits. Sand mining for these minerals started in 1911 and is still continuing. But, unfortunately all the problems that Alappad faces now, have its root on mining of this mineral sand. The land area is continuously diminishing due to sea erosion. The mining has also caused displacement of people and environmental degradation. Marine life also is getting affected by mining on beach and pollution. The inhabitants are fishermen who are largely dependent on the eco-system for a living. So loss of environmental sustainability subsequently affects social sustainability too. Now the damage has reached a point beyond which our actions may not be able to make any impact. This was one of the most affected areas of the 2004 tsunami and the environmental degradation has further increased the vulnerability. So this study focuses on understanding the concerns related to the resource utilization, environment and the indigenous community staying there, and on formulating suitable strategies to restore the sustainability of the area. An extensive study was conducted on site, to find out the physical, social, and economical characteristics of the area. A focus group discussion with the inhabitants shed light on different issues they face in their day-to-day life. The analysis of all these data, led to the formation of a new development vision for the area which focuses on environmental restoration and socio-economic development while allowing controlled exploitation of resources. A participatory approach is formulated which enables these three aspects through community based programs.Keywords: Community development, Disaster resilience, Ecological restoration, Environmental sustainability, Social-environmental planning, Social Sustainability
Procedia PDF Downloads 1115294 Analyzing Nonsimilar Convective Heat Transfer in Copper/Alumina Nanofluid with Magnetic Field and Thermal Radiations
Authors: Abdulmohsen Alruwaili
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A partial differential system featuring momentum and energy balance is often used to describe simulations of flow initiation and thermal shifting in boundary layers. The buoyancy force in terms of temperature is factored in the momentum balance equation. Buoyancy force causes the flow quantity to fluctuate along the streamwise direction 𝑋; therefore, the problem can be, to our best knowledge, analyzed through nonsimilar modeling. In this analysis, a nonsimilar model is evolved for radiative mixed convection of a magnetized power-law nanoliquid flow on top of a vertical plate installed in a stationary fluid. The upward linear stretching initiated the flow in the vertical direction. Assuming nanofluids are composite of copper (Cu) and alumina (Al₂O₃) nanoparticles, the viscous dissipation in this case is negligible. The nonsimilar system is dealt with analytically by local nonsimilarity (LNS) via numerical algorithm bvp4c. Surface temperature and flow field are shown visually in relation to factors like mixed convection, magnetic field strength, nanoparticle volume fraction, radiation parameters, and Prandtl number. The repercussions of magnetic and mixed convection parameters on the rate of energy transfer and friction coefficient are represented in tabular forms. The results obtained are compared to the published literature. It is found that the existence of nanoparticles significantly improves the temperature profile of considered nanoliquid. It is also observed that when the estimates of the magnetic parameter increase, the velocity profile decreases. Enhancement in nanoparticle concentration and mixed convection parameter improves the velocity profile.Keywords: nanofluid, power law model, mixed convection, thermal radiation
Procedia PDF Downloads 325293 On Voice in English: An Awareness Raising Attempt on Passive Voice
Authors: Meral Melek Unver
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This paper aims to explore ways to help English as a Foreign Language (EFL) learners notice and revise voice in English and raise their awareness of when and how to use active and passive voice to convey meaning in their written and spoken work. Because passive voice is commonly preferred in certain genres such as academic essays and news reports, despite the current trends promoting active voice, it is essential for learners to be fully aware of the meaning, use and form of passive voice to better communicate. The participants in the study are 22 EFL learners taking a one-year intensive English course at a university, who will receive English medium education (EMI) in their departmental studies in the following academic year. Data from students’ written and oral work was collected over a four-week period and the misuse or inaccurate use of passive voice was identified. The analysis of the data proved that they failed to make sensible decisions about when and how to use passive voice partly because the differences between their mother tongue and English and because they were not aware of the fact that active and passive voice would not alternate all the time. To overcome this, a Test-Teach-Test shape lesson, as opposed to a Present-Practice-Produce shape lesson, was designed and implemented to raise their awareness of the decisions they needed to make in choosing the voice and help them notice the meaning and use of passive voice through concept checking questions. The results first suggested that awareness raising activities on the meaning and use of voice in English would be beneficial in having accurate and meaningful outcomes from students. Also, helping students notice and renotice passive voice through carefully designed activities would help them internalize the use and form of it. As a result of the study, a number of activities are suggested to revise and notice passive voice as well as a short questionnaire to help EFL teachers to self-reflect on their teaching.Keywords: voice in English, test-teach-test, passive voice, English language teaching
Procedia PDF Downloads 2215292 Creating Database and Building 3D Geological Models: A Case Study on Bac Ai Pumped Storage Hydropower Project
Authors: Nguyen Chi Quang, Nguyen Duong Tri Nguyen
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This article is the first step to research and outline the structure of the geotechnical database in the geological survey of a power project; in the context of this report creating the database that has been carried out for the Bac Ai pumped storage hydropower project. For the purpose of providing a method of organizing and storing geological and topographic survey data and experimental results in a spatial database, the RockWorks software is used to bring optimal efficiency in the process of exploiting, using, and analyzing data in service of the design work in the power engineering consulting. Three-dimensional (3D) geotechnical models are created from the survey data: such as stratigraphy, lithology, porosity, etc. The results of the 3D geotechnical model in the case of Bac Ai pumped storage hydropower project include six closely stacked stratigraphic formations by Horizons method, whereas modeling of engineering geological parameters is performed by geostatistical methods. The accuracy and reliability assessments are tested through error statistics, empirical evaluation, and expert methods. The three-dimensional model analysis allows better visualization of volumetric calculations, excavation and backfilling of the lake area, tunneling of power pipelines, and calculation of on-site construction material reserves. In general, the application of engineering geological modeling makes the design work more intuitive and comprehensive, helping construction designers better identify and offer the most optimal design solutions for the project. The database always ensures the update and synchronization, as well as enables 3D modeling of geological and topographic data to integrate with the designed data according to the building information modeling. This is also the base platform for BIM & GIS integration.Keywords: database, engineering geology, 3D Model, RockWorks, Bac Ai pumped storage hydropower project
Procedia PDF Downloads 1685291 Effects of Foam Rolling with Different Application Volumes on the Isometric Force of the Calf Muscle with Consideration of Muscle Activity
Authors: T. Poppendieker, H. Maurer, C. Segieth
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Over the past ten years, foam rolling has become a new trend in the fitness and health market. It is also a frequently used technique for self-massage. However, the scope of effects from foam rolling has only recently started to be researched and understood. The focus of this study is to examine the effects of prolonged foam rolling on muscle performance. Isometric muscle force was used as a parameter to determine an improving impact of the myofascial roller in two different application volumes. Besides the maximal muscle force, data were also collected on muscle activation during all tests. Twenty-four (17 females, 7 males) healthy students with an average age of 23.4 ± 2.8 years were recruited. The study followed a cross-over pre-/post design in which the order of conditions was counterbalanced. The subjects performed a one-minute and three-minute foam rolling application set on two separate days. Isometric maximal muscle force of the dominant calf was tested before and after the self-myofascial release application. The statistic software program SPSS 22 was used to analyze the data of the maximal isometric force of the calf muscle by a 2 x 2 (time of measurement x intervention) analysis of variance with repeated measures. The statistic significance level was set at p ≤ 0.05. Neither for the main effect of time of measurement (F(1,23) = .93, p = .36, f = .20) nor for the interaction of time of measurement x intervention (F(1,23) = 1.99, p = .17, f = 0.29) significant p-values were found. However, the effect size indicates a mean interaction effect with a tendency of greater pre-post improvements under the three-minute foam rolling condition. Changes in maximal force did not correlate with changes in EMG-activity (r = .02, p = .95 in the short and r = -.11, p = .65 in the long rolling condition). Results support findings of previous studies and suggest a positive potential for use of the foam roll as a means for keeping muscle force at least at the same performance level while leading to an increase in flexibility.Keywords: application volume differences, foam rolling, isometric maximal force, self-myofascial release
Procedia PDF Downloads 2875290 Magneto-Hydrodynamic Mixed Convective Fluid Flow through Two Parallel Vertical Plates Channel with Hall, Chemical Reaction, and Thermal Radiation Effects
Authors: Okuyade Ighoroje Wilson Ata
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Magneto-hydrodynamic mixed convective chemically reacting fluid flow through two parallel vertical plates channel with Hall, radiation, and chemical reaction effects are examined. The fluid is assumed to be chemically reactive, electrically conducting, magnetically susceptible, viscous, incompressible, and Newtonian; the plates are porous, electrically conductive, and heated to a high-temperature regime to generate thermal rays. The flow system is highly interactive, such that cross/double diffusion is present. The governing equations are partial differential equations transformed into ordinary differential equations using similarity transformation and solved by the method of Homotopy Perturbation. Expressions for the concentration, temperature, velocity, Nusselt number, Sherwood number, and Wall shear stress are obtained, computed, and presented graphically and tabularly. The analysis of results shows, amongst others, that an increase in the Raleigh number increases the main velocity and temperature but decreases the concentration. More so, an increase in chemical reaction rate increases the main velocity, temperature, rate of heat transfer from the terminal plate, the rate of mass transfer from the induced plate, and Wall shear stress on both the induced and terminal plates, decreasing the concentration, and the mass transfer rate from the terminal plate. Some of the obtained results are benchmarked with those of existing literature and are in consonance.Keywords: chemical reaction, hall effect, magneto-hydrodynamic, radiation, vertical plates channel
Procedia PDF Downloads 775289 Comparison of Different Artificial Intelligence-Based Protein Secondary Structure Prediction Methods
Authors: Jamerson Felipe Pereira Lima, Jeane Cecília Bezerra de Melo
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The difficulty and cost related to obtaining of protein tertiary structure information through experimental methods, such as X-ray crystallography or NMR spectroscopy, helped raising the development of computational methods to do so. An approach used in these last is prediction of tridimensional structure based in the residue chain, however, this has been proved an NP-hard problem, due to the complexity of this process, explained by the Levinthal paradox. An alternative solution is the prediction of intermediary structures, such as the secondary structure of the protein. Artificial Intelligence methods, such as Bayesian statistics, artificial neural networks (ANN), support vector machines (SVM), among others, were used to predict protein secondary structure. Due to its good results, artificial neural networks have been used as a standard method to predict protein secondary structure. Recent published methods that use this technique, in general, achieved a Q3 accuracy between 75% and 83%, whereas the theoretical accuracy limit for protein prediction is 88%. Alternatively, to achieve better results, support vector machines prediction methods have been developed. The statistical evaluation of methods that use different AI techniques, such as ANNs and SVMs, for example, is not a trivial problem, since different training sets, validation techniques, as well as other variables can influence the behavior of a prediction method. In this study, we propose a prediction method based on artificial neural networks, which is then compared with a selected SVM method. The chosen SVM protein secondary structure prediction method is the one proposed by Huang in his work Extracting Physico chemical Features to Predict Protein Secondary Structure (2013). The developed ANN method has the same training and testing process that was used by Huang to validate his method, which comprises the use of the CB513 protein data set and three-fold cross-validation, so that the comparative analysis of the results can be made comparing directly the statistical results of each method.Keywords: artificial neural networks, protein secondary structure, protein structure prediction, support vector machines
Procedia PDF Downloads 6215288 Neural Networks Based Prediction of Long Term Rainfall: Nine Pilot Study Zones over the Mediterranean Basin
Authors: Racha El Kadiri, Mohamed Sultan, Henrique Momm, Zachary Blair, Rachel Schultz, Tamer Al-Bayoumi
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The Mediterranean Basin is a very diverse region of nationalities and climate zones, with a strong dependence on agricultural activities. Predicting long term (with a lead of 1 to 12 months) rainfall, and future droughts could contribute in a sustainable management of water resources and economical activities. In this study, an integrated approach was adopted to construct predictive tools with lead times of 0 to 12 months to forecast rainfall amounts over nine subzones of the Mediterranean Basin region. The following steps were conducted: (1) acquire, assess and intercorrelate temporal remote sensing-based rainfall products (e.g. The CPC Merged Analysis of Precipitation [CMAP]) throughout the investigation period (1979 to 2016), (2) acquire and assess monthly values for all of the climatic indices influencing the regional and global climatic patterns (e.g., Northern Atlantic Oscillation [NOI], Southern Oscillation Index [SOI], and Tropical North Atlantic Index [TNA]); (3) delineate homogenous climatic regions and select nine pilot study zones, (4) apply data mining methods (e.g. neural networks, principal component analyses) to extract relationships between the observed rainfall and the controlling factors (i.e. climatic indices with multiple lead-time periods) and (5) use the constructed predictive tools to forecast monthly rainfall and dry and wet periods. Preliminary results indicate that rainfall and dry/wet periods were successfully predicted with lead zones of 0 to 12 months using the adopted methodology, and that the approach is more accurately applicable in the southern Mediterranean region.Keywords: rainfall, neural networks, climatic indices, Mediterranean
Procedia PDF Downloads 3125287 Interpreting Ecclesiastical Heritage: Meaning Making and Contentious Conversations
Authors: Alexis Thouki
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In our post-Christian societies, ecclesiastical heritage acquired a new extrovert profile aiming to reach out an increasingly diverse audience. In this context, the various motivations, interests, personalities and cultural exchanges, found in the ‘post-modern pilgrimage’, bequeath a hybrid and multidimensional character to religious tourism education. In consequence, churches have acquired the challenging role of enriching visitors cultural and spiritual capital. Despite this promising diversification to relate, reveal and provoke constructive discourses, due to the various ‘conflicting interests’, practitioners attempt to tame the rich in symbolism and meanings religious environment through ‘neutral interpretations’. This paper aims to present the results of an ongoing developing strategy related to the presentation of contentious meanings in English churches. The paper will explore some of the underlying issues related to the capacity of ‘neutrality’ to spark, downplay or eliminate contentious conversations relating to the cultural, religious, and social dimension of Christian cultural heritage thematology. In an effort to understand this issue, the paper examines the concept of neutrality and what it stands for, executing a discourse analysis in the semantic context in which the theological lexicon is interwoven with the cultural and social meanings of sacred sites. Following that, the paper examines whether the preferable interpretive strategies meet the post-modern interpretative framework which is marked by polysemy and critical active engagement. The ultimate aim of the paper is to investigate the hypothesis that the preferable neutral strategies, managing the ‘conflicting’ demands of worshippers and visitors, result in the uneven treatment of both, the religious and historical spirit of the place.Keywords: contentious dialogue, interpretation, meaning making, religious tourism
Procedia PDF Downloads 1575286 Liminal Disabled Tweens’ Identification with Disney Animations in Algeria
Authors: Selma Aitsaid
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Disney canon texts, mainly animations, are believed to have authority over children’s identities. However, most research on Disney tends to focus either on textual analysis, or Western and non-western adult audiences. In fact, there is a lack of scholarship on Disney child audiences from non-western countries though children are believed to be Disney‘s main target audience, and Disney is a global corporation that appeals to audiences from all over the world as well. Therefore, qualitative research was conducted by interviewing around twenty five Algerian disabled tweens between the age 11 to 14 on their familiarity and identification with Disney animations. The reason behind choosing disabled children is because minority groups have not been interviewed on their possible interpretations of Disney animations despite the fact that these texts have been interpreted by some scholars as being inclusive of minority groups such as queer and disabled people. To that end, this project aims to decolonize disability and Global Southern Academia by three ways. The first way is to uncover inequalities of the metropolitan thought enshrined in the global power of the metropole vis a vis the subaltern. This approach was called postcolonialism. The second way is to value non-western academic and non-academic resources. This is the project of ‘indigenous knowledge. The third way is to analyse the forms of knowledge that were produced by intellectuals in colonized countries as a response to Western Academic hegemony. Consequently, this research endeavored to unravel the inequality, the dynamics of neocolonialism and subordination to colonial discourses within the Algerian discourse on disability and other knowledge such as tweenhood, childhood and non-western viewership, which are mainly defined through Western lenses. Algerian resources were included with the aim of enhancing an academic collaboration between the North and South as well. The findings showed that the postcolonial context had an impact on how children perceive Disney animations. They also demonstrated that children are able to negotiate the meaning of Disney texts within their own context.Keywords: child audiences, Algeria, childhood, disability, Disney animations, global South, postcolonialism, tweens, Western hegemony
Procedia PDF Downloads 1185285 From Restraint to Obligation: The Protection of the Environment in Times of Armed Conflict
Authors: Aaron Walayat
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Protection of the environment in international law has been one of the most developed in the context of international humanitarian law. This paper examines the history of the protection of the environment in times of armed conflict, beginning with the traditional notion of restraint observed in antiquity towards the obligation to protect the environment, examining the treaties and agreements, both binding and non-binding which have contributed to environmental protection in war. The paper begins with a discussion of the ancient concept of restraint. This section examines the social norms in favor of protection of the environment as observed in the Bible, Greco-Roman mythology, and even more contemporary literature. The study of the traditional rejection of total war establishes the social foundation on which the current legal regime has stemmed. The paper then studies the principle of restraint as codified in international humanitarian law. It mainly examines Additional Protocol I of the Geneva Convention of 1949 and existing international law concerning civilian objects and the principles of international humanitarian law in the classification between civilian objects and military objectives. The paper then explores the environment’s classification as both a military objective and as a civilian object as well as explores arguments in favor of the classification of the whole environment as a civilian object. The paper will then discuss the current legal regime surrounding the protection of the environment, discussing some declarations and conventions including the 1868 Declaration of St. Petersburg, the 1907 Hague Convention No. IV, the Geneva Conventions, and the 1976 Environmental Modification Convention. The paper concludes with the outline noting the movement from codification of the principles of restraint into the various treaties, agreements, and declarations of the current regime of international humanitarian law. This paper provides an analysis of the history and significance of the relationship between international humanitarian law as a major contributor to the growing field of international environmental law.Keywords: armed conflict, environment, legal regime, restraint
Procedia PDF Downloads 2045284 Characterization of the GntR Family Transcriptional Regulator Rv0792c: A Potential Drug Target for Mycobacterium tuberculosis
Authors: Thanusha D. Abeywickrama, Inoka C. Perera, Genji Kurisu
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Tuberculosis, considered being as the ninth leading cause of death worldwide, cause from a single infectious agent M. tuberculosis and the drug resistance nature of this bacterium is a continuing threat to the world. Therefore TB preventing treatment is expanding, where this study designed to analyze the regulatory mechanism of GntR transcriptional regulator gene Rv0792c, which lie between several genes codes for some hypothetical proteins, a monooxygenase and an oxidoreductase. The gene encoding Rv0792c was cloned into pET28a and expressed protein was purified to near homogeneity by Nickel affinity chromatography. It was previously reported that the protein binds within the intergenic region (BS region) between Rv0792c gene and monooxygenase (Rv0793). This resulted in binding of three protein molecules with the BS region suggesting tight control of monooxygenase as well as its own gene. Since monooxygenase plays a key role in metabolism, this gene may have a global regulatory role. The natural ligand for this regulator is still under investigation. In relation to the Rv0792 protein structure, a Circular Dichroism (CD) spectrum was carried out to determine its secondary structure elements. Percentage-wise, 17.4% Helix, 21.8% Antiparallel, 5.1% Parallel, 12.3% turn and 43.5% other were revealed from CD spectrum data under room temperature. Differential Scanning Calorimetry (DSC) was conducted to assess the thermal stability of Rv0792, which the melting temperature of protein is 57.2 ± 0.6 °C. The graph of heat capacity (Cp) versus temperature for the best fit was obtained for non-two-state model, which concludes the folding of Rv0792 protein occurs through stable intermediates. Peak area (∆HCal ) and Peak shape (∆HVant ) was calculated from the graph and ∆HCal / ∆HVant was close to 0.5, suggesting dimeric nature of the protein.Keywords: CD spectrum, DSC analysis, GntR transcriptional regulator, protein structure
Procedia PDF Downloads 2225283 Modified Weibull Approach for Bridge Deterioration Modelling
Authors: Niroshan K. Walgama Wellalage, Tieling Zhang, Richard Dwight
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State-based Markov deterioration models (SMDM) sometimes fail to find accurate transition probability matrix (TPM) values, and hence lead to invalid future condition prediction or incorrect average deterioration rates mainly due to drawbacks of existing nonlinear optimization-based algorithms and/or subjective function types used for regression analysis. Furthermore, a set of separate functions for each condition state with age cannot be directly derived by using Markov model for a given bridge element group, which however is of interest to industrial partners. This paper presents a new approach for generating Homogeneous SMDM model output, namely, the Modified Weibull approach, which consists of a set of appropriate functions to describe the percentage condition prediction of bridge elements in each state. These functions are combined with Bayesian approach and Metropolis Hasting Algorithm (MHA) based Markov Chain Monte Carlo (MCMC) simulation technique for quantifying the uncertainty in model parameter estimates. In this study, factors contributing to rail bridge deterioration were identified. The inspection data for 1,000 Australian railway bridges over 15 years were reviewed and filtered accordingly based on the real operational experience. Network level deterioration model for a typical bridge element group was developed using the proposed Modified Weibull approach. The condition state predictions obtained from this method were validated using statistical hypothesis tests with a test data set. Results show that the proposed model is able to not only predict the conditions in network-level accurately but also capture the model uncertainties with given confidence interval.Keywords: bridge deterioration modelling, modified weibull approach, MCMC, metropolis-hasting algorithm, bayesian approach, Markov deterioration models
Procedia PDF Downloads 7285282 Evaluation and Analysis of ZigBee-Based Wireless Sensor Network: Home Monitoring as Case Study
Authors: Omojokun G. Aju, Adedayo O. Sule
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ZigBee wireless sensor and control network is one of the most popularly deployed wireless technologies in recent years. This is because ZigBee is an open standard lightweight, low-cost, low-speed, low-power protocol that allows true operability between systems. It is built on existing IEEE 802.15.4 protocol and therefore combines the IEEE 802.15.4 features and newly added features to meet required functionalities thereby finding applications in wide variety of wireless networked systems. ZigBee‘s current focus is on embedded applications of general-purpose, inexpensive, self-organising networks which requires low to medium data rates, high number of nodes and very low power consumption such as home/industrial automation, embedded sensing, medical data collection, smart lighting, safety and security sensor networks, and monitoring systems. Although the ZigBee design specification includes security features to protect data communication confidentiality and integrity, however, when simplicity and low-cost are the goals, security is normally traded-off. A lot of researches have been carried out on ZigBee technology in which emphasis has mainly been placed on ZigBee network performance characteristics such as energy efficiency, throughput, robustness, packet delay and delivery ratio in different scenarios and applications. This paper investigate and analyse the data accuracy, network implementation difficulties and security challenges of ZigBee network applications in star-based and mesh-based topologies with emphases on its home monitoring application using the ZigBee ProBee ZE-10 development boards for the network setup. The paper also expose some factors that need to be considered when designing ZigBee network applications and suggest ways in which ZigBee network can be designed to provide more resilient to network attacks.Keywords: home monitoring, IEEE 802.14.5, topology, wireless security, wireless sensor network (WSN), ZigBee
Procedia PDF Downloads 3835281 Prevalence of Different Poultry Parasitoses in Farms Modern in the North of Ivory Coast
Authors: Coulibaly Fatoumata, Gragnon Biego, Aka N. David, Mbari K. Benjamin, Soro Y. René, Ndiaye Jean-louis
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Poultry is nowadays one of the most consumed sources of protein, and its livestock represents one of the few opportunities for savings, investment and protection against risk. It provides income for the most vulnerable sections of society, in particular, women (70%) and children who mainly practice this breeding. A study was conducted in the commune of Korhogo at the level of 52 poultry farms, the objective of which was to know the epidemiological situation of parasitism external and internal poultry in order to contribute to the improvement of the health status of modern poultry farms in the said commune. The method described by OIE (2005), consisting of using the standard formula (n = δ2*p*(1-p) *c /i2), made it possible to calculate the size of the sample. Then, samples of droppings and ectoparasites were taken from the affected farms. After analysis and identification, two (2) species of mallophagous lice, including Menopon gallinae (50%) and Menacanthus stramineus (33%) and a species of bug Cimex lectularius (17%) were highlighted. The laying hens were more infested than broilers. Regarding gastrointestinal parasites, different species (six) have been identified: Trichostrongylus tenuis (17%), Syngamus trachea (19%), Heterakis sp (10%), Ascaridia sp (17%), Raillietina sp (8%) and Eimeria sp (29%). In addition, coccidiosis (Eimeria sp) proved to be the dominant pathology representing 67% of pathologies in broiler farms and 33% in poultry farms. The presence of these parasitoses in these modern farms constitutes a constraint major contribution to productivity and their development In view of all these difficulties, proposals have been made in order to participate in the establishment of a good prophylaxis program (health and medical). In addition, the Ivorian government, with the support of veterinarians, must interfere more in the organization of the health monitoring of traditional chickens and poultry in general through supervision and training in order to preserve public health ( animal, human and environmental health).Keywords: gastrointestinal parasites, ectoparasites, pathologies, poultry, korhogo.
Procedia PDF Downloads 855280 Solving LWE by Pregressive Pumps and Its Optimization
Authors: Leizhang Wang, Baocang Wang
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General Sieve Kernel (G6K) is considered as currently the fastest algorithm for the shortest vector problem (SVP) and record holder of open SVP challenge. We study the lattice basis quality improvement effects of the Workout proposed in G6K, which is composed of a series of pumps to solve SVP. Firstly, we use a low-dimensional pump output basis to propose a predictor to predict the quality of high-dimensional Pumps output basis. Both theoretical analysis and experimental tests are performed to illustrate that it is more computationally expensive to solve the LWE problems by using a G6K default SVP solving strategy (Workout) than these lattice reduction algorithms (e.g. BKZ 2.0, Progressive BKZ, Pump, and Jump BKZ) with sieving as their SVP oracle. Secondly, the default Workout in G6K is optimized to achieve a stronger reduction and lower computational cost. Thirdly, we combine the optimized Workout and the Pump output basis quality predictor to further reduce the computational cost by optimizing LWE instances selection strategy. In fact, we can solve the TU LWE challenge (n = 65, q = 4225, = 0:005) 13.6 times faster than the G6K default Workout. Fourthly, we consider a combined two-stage (Preprocessing by BKZ- and a big Pump) LWE solving strategy. Both stages use dimension for free technology to give new theoretical security estimations of several LWE-based cryptographic schemes. The security estimations show that the securities of these schemes with the conservative Newhope’s core-SVP model are somewhat overestimated. In addition, in the case of LAC scheme, LWE instances selection strategy can be optimized to further improve the LWE-solving efficiency even by 15% and 57%. Finally, some experiments are implemented to examine the effects of our strategies on the Normal Form LWE problems, and the results demonstrate that the combined strategy is four times faster than that of Newhope.Keywords: LWE, G6K, pump estimator, LWE instances selection strategy, dimension for free
Procedia PDF Downloads 605279 Evaluation of Pragmatic Information in an English Textbook: Focus on Requests
Authors: Israa A. Qari
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Learning to request in a foreign language is a key ability within pragmatics language teaching. This paper examines how requests are taught in English Unlimited Book 3 (Cambridge University Press), an EFL textbook series employed by King Abdulaziz University in Jeddah, Saudi Arabia to teach advanced foundation year students English. The focus of analysis is the evaluation of the request linguistic strategies present in the textbook, frequency of the use of these strategies, and the contextual information provided on the use of these linguistic forms. The researcher collected all the linguistic forms which consisted of the request speech act and divided them into levels employing the CCSARP request coding manual. Findings demonstrated that simple and commonly employed request strategies are introduced. Looking closely at the exercises throughout the chapters, it was noticeable that the book exclusively employed the most direct form of requesting (the imperative) when giving learners instructions: e.g. listen, write, ask, answer, read, look, complete, choose, talk, think, etc. The book also made use of some other request strategies such as ‘hedged performatives’ and ‘query preparatory’. However, it was also found that many strategies were not dealt with in the book, specifically strategies with combined functions (e.g. possibility, ability). On a sociopragmatic level, a strong focus was found to exist on standard situations in which relations between the requester and requestee are clear. In general, contextual information was communicated implicitly only. The textbook did not seem to differentiate between formal and informal request contexts (register) which might consequently impel students to overgeneralize. The paper closes with some recommendations for textbook and curriculum designers. Findings are also contrasted with previous results from similar body of research on EFL requests.Keywords: EFL, requests, saudi, speech acts, textbook evaluation
Procedia PDF Downloads 1355278 Physiological and Biochemical Based Analysis to Assess the Efficacy of Mulch under Partial Root Zone Drying in Wheat
Authors: Salman Ahmad, Muhammad Aown Sammar Raza, Muhammad Farrukh Saleem, Rashid Iqbal, Muhammad Saqlain Zaheer, Muhammad Usman Aslam, Imran Haider, Muhammad Adnan Nazar, Muhammad Ali
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Among the various abiotic stresses, drought stress is one of the most challenging for field crops. Wheat is one of the major staple food of the world, which is highly affected by water deficit stress in the current scenario of climate change. In order to ensure food security by depleting water resources, there is an urgent need to adopt technologies which result in sufficient crop yield with less water consumption. Mulching and partial rootzone drying (PRD) are two important management techniques used for water conservation and to mitigate the negative impacts of drought. The experiment was conducted to screen out the best-suited mulch for wheat under PRD system. Two water application techniques (I1= full irrigation I2= PRD irrigation) and four mulch treatments (M0= un-mulched, M1= black plastic mulch, M2= wheat straw mulch and M4= cotton sticks mulch) were conducted in completely randomized design with four replications. The treatment, black plastic mulch was performed the best than other mulch treatments. For irrigation levels, higher values of growth, physiological and water-related parameters were recorded in control treatment while, quality traits and enzymatic activities were higher under partial root zone drying. The current study concluded that adverse effects of drought on wheat can be significantly mitigated by using mulches but black plastic mulch was best suited for partial rootzone drying irrigation system in wheat.Keywords: antioxidants, leaf water relations, Mulches, osmolytes, partial root zone drying, photosynthesis
Procedia PDF Downloads 2655277 Analysis of Local Food Sources in Ethiopia
Authors: Bereket Amare Mulu
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Ethiopia is one of the countries that consists of a huge variety of botanical resources as compared to the world. The agroclimatic is suitable for a variety of plants to grow effectively throughout the year. Sources of food plants are basic items for people in the world. Production of food items is a prior activity and needs more resources and attention to produce a huge amount of production. The local food is rich in nutrition and healthful foods. The local food is fresh and not exposed to infections easily. The community can easily get the food items in their surroundings. The local food sources are not expensive when it is compared to the other proceed food items, and it is affordable to the community purchasing power. The food is very tasty and palatable capacity by the whole community categories. The basic problems in Ethiopia are the community experiences some of the common food source items. On the contrary, inefficient food production, low economic growth, and climate variability affected food production. This leads to serious food shortages and acute health problems. The objective of the study is to identify local food sources and analyze the advantage and benefits of local food sources. Casava is one of the root crop plants in Ethiopia and easily adapts to any type of agroecology in every place in the country. 50 community members have been identified to prepare casava in different forms of food items. They have prepared in the forms of Bread, Injera, Porridge, Boiled casava, fried chips Casava, and Cocktails. The prepared food items have been exposed to the community as a food festival to eat and taste how much interesting Even though there is a cultural barrier to eating the food items, the community had the food and tasted it the food. The result showed that community awareness is still not addressed the benefits of local food sources yet. The local food has high nutritional value and healthful foods. The local food sources are fresh and easily produced in every place of the country.Keywords: bread, cassava, injera, nutrition
Procedia PDF Downloads 1045276 Change Management as a Critical Success Factor In E-Government initiatives
Authors: Mohammed Alassim
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In 2014, a UN survey stated that: "The greatest challenge to the adoption of whole-of government, which fundamentally rests on increased collaboration, is resistance to change among government actors". Change management has experienced both theoretically and practically many transformation over the years. When organizations have to implement radical changes, they have to encounter a plethora of issues which leads to ineffective or inefficient implementation of change in most cases. 70% of change projects fail because of human issues. It has been cited that” most studies still show a 60-70% failure rate for organizational change projects — a statistic that has stayed constant from the 1970’s to the present.”. E-government involves not just technical change but cultural, policy, social and organizational evolution. Managing change and overcoming resistance to change is seen as crucial in the success of E-government projects. Resistance can be from different levels in the organization (top management, middle management or employees at operational levels). There can be many reasons for resistance including fear of change and insecurity, lack of knowledge and absence of commitment from management to implement the change. The purpose of this study is to conduct in-depth research to understand the process of change and to identify the critical factors that have led to resistance from employees at different levels (top management, Middle management and operational employees) during e-government initiatives in the public sector in Saudi Arabia. The study is based on qualitative and empirical research methods conducted in the public sector in the Kingdom of Saudi Arabia. This research will use triangulation in data method (interview, group discussion and document review). This research will contribute significantly to knowledge in this field and will identify the measures that can be taken to reduce resistance to change, Upon analysis recommendations or model will be offered which can enable decision makers in public sector in Saudi Arabia how to plan, implement and evaluate change in e-government initiatives via change management strategy.Keywords: change management, e-government, managing change, resistance to change
Procedia PDF Downloads 3165275 Son Preference in Afghanistan and Its Impact on Fertility Outcomes
Authors: Saha Naseri
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Introduction/Objective: Son preference, a preference for sons over daughters, is a practice deeply-rooted in gender inequality that is widespread in many societies and across different religions and cultures. In this study, we are aiming to study the effects of son preference on fertility outcomes (birth interval and current contraceptive use) in Afghanistan, where have been perceived with high rates of son preference. The objectives of the study are to examine the association between the sex of the previous child and the duration of the subsequent birth interval and to evaluate the effect of son preference on current contraceptive use. Methodology: Afghanistan Demographic and Health Survey (DHS) (2015) was used to study the impact of son preference on fertility outcomes among married women. The data collected from 28,661 on currently-married women, aged between 15 and 49 years who have at least one child, have used to conduct this quantitative study. Outcomes of interest are birth interval and current contraceptive use. Simple and multiple regression analysis have been conducted to assess the effect of son preference on these fertility outcomes. Results: The present study has highlighted that son preference somehow exists among married women in Afghanistan. It is indicated that the sex of the first birth is significantly associated with the succeeding birth interval. Having a female child as the first baby was associated with a shorter average succeeding birth interval by 1.8 months compared to a baby boy (p-value = 0.000). For the second model, the results identified that women who desire for more sons have 7% higher odds to be current contraceptive user compared to those who have no preference (p-value = 0.03). The latter results do not indicate the son preference. However, one limitation for this result was the timeliness of the questions asked since contraceptive use in the current time was asked along with a question on ‘future’ desired sex composition. Moreover, women may have just given birth and want to reach a certain time span of birth interval before planning for another child, even if it was a boy, which might have affected the results. Conclusion: Overall, this study has demonstrated that there is a positive relationship between son preference and one main fertility behaviors, birth interval. The second fertility outcome, current contraceptive use, was not a good indicator to measure son preference. Based on the finding, recommendations will be made for appropriate interventions addressing gender norms and related fertility decisions.Keywords: Afghanistan, birth interval, contraceptive, son preference
Procedia PDF Downloads 1735274 Modelling of Heat Generation in a 18650 Lithium-Ion Battery Cell under Varying Discharge Rates
Authors: Foo Shen Hwang, Thomas Confrey, Stephen Scully, Barry Flannery
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Thermal characterization plays an important role in battery pack design. Lithium-ion batteries have to be maintained between 15-35 °C to operate optimally. Heat is generated (Q) internally within the batteries during both the charging and discharging phases. This can be quantified using several standard methods. The most common method of calculating the batteries heat generation is through the addition of both the joule heating effects and the entropic changes across the battery. In addition, such values can be derived by identifying the open-circuit voltage (OCV), nominal voltage (V), operating current (I), battery temperature (T) and the rate of change of the open-circuit voltage in relation to temperature (dOCV/dT). This paper focuses on experimental characterization and comparative modelling of the heat generation rate (Q) across several current discharge rates (0.5C, 1C, and 1.5C) of a 18650 cell. The analysis is conducted utilizing several non-linear mathematical functions methods, including polynomial, exponential, and power models. Parameter fitting is carried out over the respective function orders; polynomial (n = 3~7), exponential (n = 2) and power function. The generated parameter fitting functions are then used as heat source functions in a 3-D computational fluid dynamics (CFD) solver under natural convection conditions. Generated temperature profiles are analyzed for errors based on experimental discharge tests, conducted at standard room temperature (25°C). Initial experimental results display low deviation between both experimental and CFD temperature plots. As such, the heat generation function formulated could be easier utilized for larger battery applications than other methods available.Keywords: computational fluid dynamics, curve fitting, lithium-ion battery, voltage drop
Procedia PDF Downloads 955273 Investment and Economic Growth: An Empirical Analysis for Tanzania
Authors: Manamba Epaphra
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This paper analyzes the causal effect between domestic private investment, public investment, foreign direct investment and economic growth in Tanzania during the 1970-2014 period. The modified neo-classical growth model that includes control variables such as trade liberalization, life expectancy and macroeconomic stability proxied by inflation is used to estimate the impact of investment on economic growth. Also, the economic growth models based on Phetsavong and Ichihashi (2012), and Le and Suruga (2005) are used to estimate the crowding out effect of public investment on private domestic investment on one hand and foreign direct investment on the other hand. A correlation test is applied to check the correlation among independent variables, and the results show that there is very low correlation suggesting that multicollinearity is not a serious problem. Moreover, the diagnostic tests including RESET regression errors specification test, Breusch-Godfrey serial correlation LM test, Jacque-Bera-normality test and white heteroskedasticity test reveal that the model has no signs of misspecification and that, the residuals are serially uncorrelated, normally distributed and homoskedastic. Generally, the empirical results show that the domestic private investment plays an important role in economic growth in Tanzania. FDI also tends to affect growth positively, while control variables such as high population growth and inflation appear to harm economic growth. Results also reveal that control variables such as trade openness and life expectancy improvement tend to increase real GDP growth. Moreover, a revealed negative, albeit weak, association between public and private investment suggests that the positive effect of domestic private investment on economic growth reduces when public investment-to-GDP ratio exceeds 8-10 percent. Thus, there is a great need for promoting domestic saving so as to encourage domestic investment for economic growth.Keywords: FDI, public investment, domestic private investment, crowding out effect, economic growth
Procedia PDF Downloads 2905272 Transient Simulation Using SPACE for ATLAS Facility to Investigate the Effect of Heat Loss on Major Parameters
Authors: Suhib A. Abu-Seini, Kyung-Doo Kim
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A heat loss model for ATLAS facility was introduced using SPACE code predefined correlations and various dialing factors. As all previous simulations were carried out using a heat loss free input; the facility was considered to be completely insulated and the core power was reduced by the experimentally measured values of heat loss to compensate to the account for the loss of heat, this study will consider heat loss throughout the simulation. The new heat loss model will be affecting SPACE code simulation as heat being leaked out of the system throughout a transient will alter many parameters corresponding to temperature and temperature difference. For that, a Station Blackout followed by a multiple Steam Generator Tube Rupture accident will be simulated using both the insulated system approach and the newly introduced heat loss input of the steady state. Major parameters such as system temperatures, pressure values, and flow rates to be put into comparison and various analysis will be suggested upon it as the experimental values will not be the reference to validate the expected outcome. This study will not only show the significance of heat loss consideration in the processes of prevention and mitigation of various incidents, design basis and beyond accidents as it will give a detailed behavior of ATLAS facility during both processes of steady state and major transient, but will also present a verification of how credible the data acquired of ATLAS are; since heat loss values for steady state were already mismatched between SPACE simulation results and ATLAS data acquiring system. Acknowledgement- This work was supported by the Korean institute of Energy Technology Evaluation and Planning (KETEP) and the Ministry of Trade, Industry & Energy (MOTIE) of the Republic of Korea.Keywords: ATLAS, heat loss, simulation, SPACE, station blackout, steam generator tube rupture, verification
Procedia PDF Downloads 2245271 Preparation, Characterisation, and Measurement of the in vitro Cytotoxicity of Mesoporous Silica Nanoparticles Loaded with Cytotoxic Pt(II) Oxadiazoline Complexes
Authors: G. Wagner, R. Herrmann
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Cytotoxic platinum compounds play a major role in the chemotherapy of a large number of human cancers. However, due to the severe side effects for the patient and other problems associated with their use, there is a need for the development of more efficient drugs and new methods for their selective delivery to the tumours. One way to achieve the latter could be in the use of nanoparticular substrates that can adsorb or chemically bind the drug. In the cell, the drug is supposed to be slowly released, either by physical desorption or by dissolution of the particle framework. Ideally, the cytotoxic properties of the platinum drug unfold only then, in the cancer cell and over a longer period of time due to the gradual release. In this paper, we report on our first steps in this direction. The binding properties of a series of cytotoxic Pt(II) oxadiazoline compounds to mesoporous silica particles has been studied by NMR and UV/vis spectroscopy. High loadings were achieved when the Pt(II) compound was relatively polar, and has been dissolved in a relatively nonpolar solvent before the silica was added. Typically, 6-10 hours were required for complete equilibration, suggesting the adsorption did not only occur to the outer surface but also to the interior of the pores. The untreated and Pt(II) loaded particles were characterised by C, H, N combustion analysis, BET/BJH nitrogen sorption, electron microscopy (REM and TEM) and EDX. With the latter methods we were able to demonstrate the homogenous distribution of the Pt(II) compound on and in the silica particles, and no Pt(II) bulk precipitate had formed. The in vitro cytotoxicity in a human cancer cell line (HeLa) has been determined for one of the new platinum compounds adsorbed to mesoporous silica particles of different size, and compared with the corresponding compound in solution. The IC50 data are similar in all cases, suggesting that the release of the Pt(II) compound was relatively fast and possibly occurred before the particles reached the cells. Overall, the platinum drug is chemically stable on silica and retained its activity upon prolonged storage.Keywords: cytotoxicity, mesoporous silica, nanoparticles, platinum compounds
Procedia PDF Downloads 321