Search results for: fade depth
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3161

Search results for: fade depth

2681 Validating the Home Experiences of Children that Negatively Impact Their Right to Education in South Africa: The Case of HIV/AIDS Orphans and Vulnerable Children (OVCs) Living in the Amatole District

Authors: Tatenda Manomano, Moreblessing Memory Ndonga

Abstract:

In South Africa and the world over, despite an array of commendable policies to protect the rights of children, the situation on the ground indicates that HIV/AIDS continues to pose increasing challenges on the children’s’ right to education due to the death of their parents. This study sought to validate the home experiences of children that negatively impact on their right to education in South Africa with a case of HIV/AIDS orphans and vulnerable children (OVCs) in Amatole District. The study utilized a qualitative research method in collecting the feelings, views and attitudes of these children to establish the children’s home experiences. An interview guide with semi-structured questions was used to steer the one-on-one in-depth interviews with children from Parkside Primary School, Langa-Liphumile High School and one anonymous school in East London, Eastern Cape Province. 5 learners were purposively selected from each school and subjected to a one-on-one interview with the researcher. The researcher purposively selected one teacher per school, 2 members each from 3 community based organizations (CBOs) who were also subjected to a one-on-one in-depth interview. The findings indicated these negative experiences of the OVCs in their homes such as; attendance to a school was poor; academic performance was low; enrollment in schools was very low and abuse of these children was high. These researchers recommend for psychosocial support for these children to be placed in the schools; integration of HIV/AIDS programmes to target especially the OVCs; social workers should ensure that they regularly do home visits to these OVCs to establish whether the home circumstances these children are still conducive for them. It is hoped that the findings from this paper will be an asset that other researchers, policy makers, the government and NGOs/CBOs will take into consideration for the benefit of OVCs.

Keywords: orphaned and vulnerable children (OVCs), HIV, AIDS, home experiences

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2680 Bowing of a Pipeline from Longitudinal Compressive Stress Induced by Ground Movement

Authors: Gennaro Marino

Abstract:

This paper concerns a case of a 10.75 inch diameter buried gas transmission line which was exposed to mine subsidence ground movements. The pipeline was buried about 4ft. below the surface with maximum operating pressure of 1440 psi. The mine subsidence movement was the result of long walling ore at a depth of approximately 1600 ft. As ore extraction progressed, the stress in the monitored pipeline worsened and was approaching unacceptable levels. The excessive pipe compression resulted when it was exposed to the compression zone of subsidence basin created by mining. The pipe stress reached a significant compressive level due to the extensive length of the pipe exposed to frictional ground-pipe slip resistance. The backfill ground movement slip resistance depends on normal stress around the pipe, the rate of slip, and the backfill characteristics. Normal stress depends on the burial depth of the backfill density and the lateral subsidence induced stress. The backfill in this site has a soil dry density of approximately 90 PCF. A suite of direct shear tests was conducted a residual friction angle of 36 was determined for the ambient backfill. These tests showed that the residual shearing resistance was reached within a fraction of an inch. The pipe was coated with fusion-bonded epoxy, so friction reduce factory of 0.6 can be considered. To relieve ground movement induced compressive stress, the line was uncovered. As more of the pipeline was exposed, the pipe abruptly bowed in the excavation. An analysis of this pipe formation which was performed is provided in this paper. Also discussed in this paper are ways to mitigate this pipe deformation or upheaval buckling from occurring. Keywords: Pipe Upheaval, Pipe Buckling, Ground subsidence, Buried Pipeline, Pipe Stress Mitigation.

Keywords: pipe upheaval, pipe buckling, ground subsidence, buried pipeline, pipe stress mitigation

Procedia PDF Downloads 142
2679 Determination of Some Organochlorine Pesticide Residues in Vegetable and Soil Samples from Alau Dam and Gongulong Agricultural Sites, Borno State, North Eastern Nigeria

Authors: Joseph Clement Akan, Lami Jafiya, Zaynab Muhammad Chellube, Zakari Mohammed, Fanna Inna Abdulrahman

Abstract:

Five vegetables (spinach, lettuce, cabbage, tomato, and onion) were freshly harvested from the Alau Dam and Gongulong agricultural areas for the determination of some organochlorine pesticide residues (o, p-DDE, p,p’-DDD, o,p’-DDD, p,p’-DDT, α-BHC, γ-BHC, metoxichlor, lindane, endosulfan dieldrin, and aldrin.) Soil samples were also collected at different depths for the determination of the above pesticides. Samples collection and preparation were conducted using standard procedures. The concentrations of all the pesticides in the soil and vegetable samples were determined using GC/MS SHIMADZU (GC-17A) equipped with electron capture detector (ECD). The highest concentration was that of p,p’-DDD (132.4±13.45µg/g) which was observed in the leaf of cabbage, while the lowest concentration was that of p,p’-DDT (2.34µg/g) was observed in the root of spinach. Similar trends were observed at the Gongulong agricultural area, with p,p’-DDD having the highest concentration of 153.23µg/g in the leaf of cabbage, while the lowest concentration was that of p,p’-DDT (12.45µg/g) which was observed in the root of spinach. α-BHC, γ-BHC, Methoxychlor, and lindane were detected in all the vegetable samples studied. The concentrations of all the pesticides in the soil samples were observed to be higher at a depth of 21-30cm, while the lowest concentrations were observed at a depth of 0-10cm. The concentrations of all the pesticides in the vegetables and soil samples from the two agricultural sites were observed to be at alarming levels, much higher than the maximum residue limits (MRLs) and acceptable daily intake values (ADIs) .The levels of the pesticides observed in the vegetables and soil samples investigated, are of such a magnitude that calls for special attention and laws to regulate the use and circulation of such chemicals. Routine monitoring of pesticide residues in these study areas is necessary for the prevention, control and reduction of environmental pollution, so as to minimize health risks.

Keywords: Alau Dam, gongulong, organochlorine, pesticide residues, soil, vegetables

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2678 Removal of Rhodamine B from Aqueous Solution Using Natural Clay by Fixed Bed Column Method

Authors: A. Ghribi, M. Bagane

Abstract:

The discharge of dye in industrial effluents is of great concern because their presence and accumulation have a toxic or carcinogenic effect on living species. The removal of such compounds at such low levels is a difficult problem. The adsorption process is an effective and attractive proposition for the treatment of dye contaminated wastewater. Activated carbon adsorption in fixed beds is a very common technology in the treatment of water and especially in processes of decolouration. However, it is expensive and the powdered one is difficult to be separated from aquatic system when it becomes exhausted or the effluent reaches the maximum allowable discharge level. The regeneration of exhausted activated carbon by chemical and thermal procedure is also expensive and results in loss of the sorbent. The focus of this research was to evaluate the adsorption potential of the raw clay in removing rhodamine B from aqueous solutions using a laboratory fixed-bed column. The continuous sorption process was conducted in this study in order to simulate industrial conditions. The effect of process parameters, such as inlet flow rate, adsorbent bed height, and initial adsorbate concentration on the shape of breakthrough curves was investigated. A glass column with an internal diameter of 1.5 cm and height of 30 cm was used as a fixed-bed column. The pH of feed solution was set at 8.5. Experiments were carried out at different bed heights (5 - 20 cm), influent flow rates (1.6- 8 mL/min) and influent rhodamine B concentrations (20 - 80 mg/L). The obtained results showed that the adsorption capacity increases with the bed depth and the initial concentration and it decreases at higher flow rate. The column regeneration was possible for four adsorption–desorption cycles. The clay column study states the value of the excellent adsorption capacity for the removal of rhodamine B from aqueous solution. Uptake of rhodamine B through a fixed-bed column was dependent on the bed depth, influent rhodamine B concentration, and flow rate.

Keywords: adsorption, breakthrough curve, clay, fixed bed column, rhodamine b, regeneration

Procedia PDF Downloads 255
2677 Aerosol - Cloud Interaction with Summer Precipitation over Major Cities in Eritrea

Authors: Samuel Abraham Berhane, Lingbing Bu

Abstract:

This paper presents the spatiotemporal variability of aerosols, clouds, and precipitation within the major cities in Eritrea and it investigates the relationship between aerosols, clouds, and precipitation concerning the presence of aerosols over the study region. In Eritrea, inadequate water supplies will have both direct and indirect adverse impacts on sustainable development in areas such as health, agriculture, energy, communication, and transport. Besides, there exists a gap in the knowledge on suitable and potential areas for cloud seeding. Further, the inadequate understanding of aerosol-cloud-precipitation (ACP) interactions limits the success of weather modification aimed at improving freshwater sources, storage, and recycling. Spatiotemporal variability of aerosols, clouds, and precipitation involve spatial and time series analysis based on trend and anomaly analysis. To find the relationship between aerosols and clouds, a correlation coefficient is used. The spatiotemporal analysis showed larger variations of aerosols within the last two decades, especially in Assab, indicating that aerosol optical depth (AOD) has increased over the surrounding Red Sea region. Rainfall was significantly low but AOD was significantly high during the 2011 monsoon season. Precipitation was high during 2007 over most parts of Eritrea. The correlation coefficient between AOD and rainfall was negative over Asmara and Nakfa. Cloud effective radius (CER) and cloud optical thickness (COT) exhibited a negative correlation with AOD over Nakfa within the June–July–August (JJA) season. The hybrid single-particle Lagrangian integrated trajectory (HYSPLIT) model that is used to find the path and origin of the air mass of the study region showed that the majority of aerosols made their way to the study region via the westerly and the southwesterly winds.

Keywords: aerosol-cloud-precipitation, aerosol optical depth, cloud effective radius, cloud optical thickness, HYSPLIT

Procedia PDF Downloads 112
2676 Sociological Enquiry into Occupational Risks and Its Consequences among Informal Automobile Artisans in Osun State, Nigeria

Authors: Funmilayo Juliana Afolabi, Joke Haafkens, Paul De Beer

Abstract:

Globally, there is a growing concern on reducing workplace accidents in the informal sector. However, there is a dearth of study on the perception of the informal workers on occupational risks they are exposed to. The way a worker perceives the workplace risk will influence his/her risk tolerance and risk behavior. The aim of this paper, therefore, is to have an in-depth understanding of the way the artisans perceive the risks at their workplace and how it influences their risk tolerance and risk behavior. This will help in designing meaningful intervention for the artisans and it will assist the policy makers in formulating a policy that will help them. Methods: Forty-three artisans were purposely selected for the study; data were generated through observation of the workplace and work practices of the artisans and in-depth interview from automobile artisans (Panel beater, Mechanic, Vulcanizer, and Painters) in Osun State, Nigeria. The transcriptions were coded and analyzed using MAXQDA software. Results: The perceived occupational risks among the study groups are a danger of being run over by oncoming vehicles while working by the roadside, a risk of vehicle falling on workers while working under the vehicle, cuts, and burns, fire explosion, falls from height and injuries from bursting of tires. The identified risk factors are carelessness of the workers, pressure from customers, inadequate tools, preternatural forces, God’s will and lack of apprentices that will assist them in the workplace. Furthermore, the study revealed that artisans engage in risky behavior like siphoning fuel with mouth because of perception that fuel is good for expelling worms and will make them free from any stomach upset. Conclusions: The study concluded that risky behaviors are influenced by culture, beliefs, and perception of the artisans. The study, therefore, suggested proper health and safety education for the artisans.

Keywords: automobile artisans, informal, occupational risks, Nigeria, sociological enquiry

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2675 Democratising Rivers: Local River Conflicts in Rajasthan

Authors: Renu Sisodia

Abstract:

This paper attempted to explore and explain the local level river water conflicts in the larger context of state - society relations. This study also covered causes of local level river water conflicts in the catchment area of Bandi and Arvari river of Rajasthan. The focus of the study was on the emergence of community driven, decentralised management of river water bodies and strategies used by local communities to protect and manage river water conflicts. The research is conducted through the process of designing a framework based on essential theoretical and practical findings supported by primary and secondary data. Two in depth case study is conducted to understand the phenomenon in depth. The first field site is Bandi River of Pali district, which is about the struggle between textile industries, community and the State government in which water pollution is said to be one of the driving force of the conflict. Finding shows that the state is supporting textile industries in Pali district have not been adherent to the environmental ethics. Present legal infrastructure and local institutions fail to resolve the serious problem of water pollution in Bandi River and its adverse impact on the local community as a result local community resistance against the local administration and the state government. The second case illustrates the plight of Arvari River in Alwar district. Tussle for the ownership of fisheries between local community, the private fish contractor and State government has been the main bone of contestation. To resolve this conflict local community formed conflict management mechanism named as Arvari Parliament. Arvari Parliament has its own principle and rules to resolve water conflicts related to ownership of the river and use of the river water. The research findings also highlight the co-existence between conventional and modern practices in resolving conflicts.

Keywords: water, water pollution, water conflicts, water scarcity, conflict resolution, local community

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2674 Exploring Teachers’ Professional Identity in the Context of the Current Political Conflict in Palestine

Authors: Bihan Qaimari

Abstract:

In many areas of the world there are political conflicts the consequences of which have an inevitable impact on the educational system. Palestine is one such country where the experience of political conflict, going back over many years, has had a devastating effect on the development and maintenance of a stable educational environment for children and their teachers. Up to now there have been few studies that have focussed on the effects of living and working in a war zone on the professional identity of teachers. The aim of this study is to explore how the formation of Palestinian teachers’ professional identity is affected by their experience of the current political conflict its impact on the school social culture. In order to gain an in-depth understanding of the impact of political violence on the formation of the professional identity of Palestinian teachers, a qualitative multiple case-study approach was adopted which draws on sociocultural theories of identity formation. An initial study was first conducted in six schools and this was followed by an in-depth study of teachers working in three further primary schools. Data sources included participant observation, a research diary, semi-structured group and individual interviews. Grounded theory, constant-comparative methods, and discourse analysis procedures were used to interpret the data. The findings suggest that the Palestinian primary school teachers negotiate multiple conflicting identities through their every day experiences of political conflict and the schools’ social culture. This tension is formed as a result of the historical cultural meaning that teachers construct about themselves and within the current unstable and unsettling conditions that exist in their country. In addition, the data indicate that the geographical location of the schools in relation of their proximity to the events of the political conflict also had an influence on the degree of tension inherent in teachers’ professional identity. The study makes significant theoretical, practical, and methodical contributions to the study of the formation of teachers’ professional identity in countries affected by political conflict.

Keywords: identity, political conflict, Palestine, teacher's professional identity

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2673 Sensitizing Bamboo Fabric with Antimicrobial Turmeric Dye

Authors: Varinder Kaur, Amanjit Kaur, Simran Kaur, Samriti Vaid

Abstract:

Coating of fabrics with anti-microbial dyes is an adaptable technique of protection from various diseases. Natural dyes, which are known to possess antibacterial properties, can be used for antibacterial finishing of fibers like cotton, wool, bamboo and so many. Dyeing of fabrics with natural dyes normally requires the use of mordants so that dyes can stay on the fabric as well as into interstices of the fabric during multiple washings. In this study, the mordants used are alum and chitosan for ensuring a reasonable color fastness to light and washing. Chitosan is a natural polysaccharide having significant biological and chemical properties such as biodegradability, biocompatibility, bioactivity, microbial activity and polycationicity. The metal ion of alum mordant can act as electron acceptor for electron donor to form coordination bond with the dye molecule, making them insoluble in water. The dyeing of bamboo fabric using a natural dye extracted from turmeric has been studied using conventional dyeing method. Natural dye was extracted using water as solvent by Soxhlet extraction method. The extracted color was characterized by spectroscopic studies like UV/visible and further tested for antimicrobial activity. The effect of mordants on the dyeing outcome in terms of colour depth as well as fastness properties of the dyeing was investigated. It has been found that employing the conventional dyeing technique at 100 oC, the mordanted samples were deeper in depth than their unmordanted counterparts. The results of fastness properties of the dyed fabrics were fair to good. Turmeric extract was found to enhance microbial resistance of bamboo as well as was itself as a good cause of coloration. These textiles dyed with the turmeric as natural dye can be very useful in developing clothing for infants, elderly and infirm people to protect them against common infections. The outcome of this study will provide a new feature to the interface of dyeing and pharmaceutical industry.

Keywords: antimicrobial activity, bamboo fabric, natural dye, turmeric

Procedia PDF Downloads 149
2672 Learning through Reflective Practice of Nursing Students in the Delivery Room: A Qualitative Research

Authors: Peeranan Wisanskoonwong, Sumitta Sawangtook

Abstract:

Practicum in Midwifery II is the subject that affects most students to be stressed and anxious because they lack of experiences and self-confidence in delivery baby. This study is a qualitative research. That research objectives were (1) to study learning through reflective practice of nursing students (2) to explain the effects of learning through reflective practice of nursing students in the delivery room. The selected key informant method was criterion-based selection. Thirty-two of fourth-year nursing students in Kuakarun Faculty of nursing who practiced in Delivery room at Taksin Hospital in academic year 2014 were selected. Data collection was data triangulation which consisted of in-depth interview, group discussion and reading students’ reflective practice journal. The research instruments were students’ reflective practice journal, semi-structured questionnaires for in-depth interview, group discussion. Data analysis was thematic analysis. The research result found that: The learning method through reflective practice of nursing students in the delivery room were (1) reflective practice journal (2) dialogue (3) critical thinking and problem solving (4) incident analysis (5) self-criticism (6) observation and evaluation of practice. There were eight issues that students learned through their reflective practice were that (1) students' ethics and morality. (2) students' knowledge and comprehension (3) creative thinking of students (4) communications and collaboration (5) experiential learning of students (6) students’memories and impressions (7) students’experience in delivery baby (8) self-learning of students. Learning through reflective practice supported students’ awareness in improving knowledge and learning continuously and systematically. It helped to adjust the attitude to learning and leadership to be careful which help develop their skills, including critical thinking and understand themselves and understand others. Recommendation for applying research results: midwifery and nursing lecturers can apply these results to be a guide for development their clinical teaching in delivery rooms and other wards.

Keywords: learning, reflection, birth, qualitative research

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2671 The Opportunities and Challenges for Universities in Africa in Addressing Climate Change: A Qualitative Comparative Case Study of Makerere University, Uganda and University of Dar Es Salaam,Tanzania

Authors: David Ssekamate

Abstract:

The study which is work in progress examines the opportunities and challenges for universities in Africa in addressing climate change issues in their programmes. Specifically, the study attempts to examine the current academic, research and community engagement programmes on climate change implemented by the Universities; the key challenges faced by the implementing units in carrying out these programmes and; the success factors that would support universities to adequately address climate change issues in their programmes. The researcher adopted a qualitative comparative case study design with Makerere University (Uganda) and University of Dar es Salaam (Tanzania) as comparative cases. Data will be collected using semi-structured in-depth interviews, Focus Group Discussions (FDGs) and Document review. A total of 12 semi-structured in-depth interviews and 4 Focus Group Discussions will be undertaken, collecting data from 36 respondents in both Uganda and Tanzania. The data will be analyzed using content and thematic analysis methods with the help of Nvivo software. The findings are envisaged to make a significant contribution to scholarly literature on climate change education and the role of higher education in addressing climate change issues, inform policy making in the sector and development planning to strengthen the academic, research and community engagement programmes on climate change by universities in Africa. The implications of the findings may go beyond the focus on climate change but also other related sustainable development issues incorporated in academic and research programmes of universities in Africa. The results may enable universities to re-think their approaches and practices and also deal with challenges effectively in addressing climate change related issues in their programmes.

Keywords: climate change, climate change education, African universities, challenges

Procedia PDF Downloads 238
2670 E-learning resources for radiology training: Is an ideal program available?

Authors: Eric Fang, Robert Chen, Ghim Song Chia, Bien Soo Tan

Abstract:

Objective and Rationale: Training of radiology residents hinges on practical, on-the-job training in all facets and modalities of diagnostic radiology. Although residency is structured to be comprehensive, clinical exposure depends on the case mix available locally and during the posting period. To supplement clinical training, there are several e-learning resources available to allow for greater exposure to radiological cases. The objective of this study was to survey residents and faculty on the usefulness of these e-learning resources. Methods: E-learning resources were shortlisted with input from radiology residents, Google search and online discussion groups, and screened by their purported focus. Twelve e-learning resources were found to meet the criteria. Both radiology residents and experienced radiology faculty were then surveyed electronically. The e-survey asked for ratings on breadth, depth, testing capability and user-friendliness for each resource, as well as for rankings for the top 3 resources. Statistical analysis was performed using SAS 9.4. Results: Seventeen residents and fifteen faculties completed an e-survey. Mean response rate was 54% ± 8% (Range: 14- 96%). Ratings and rankings were statistically identical between residents and faculty. On a 5-point rating scale, breadth was 3.68 ± 0.18, depth was 3.95 ± 0.14, testing capability was 2.64 ± 0.16 and user-friendliness was 3.39 ± 0.13. Top-ranked resources were STATdx (first), Radiopaedia (second) and Radiology Assistant (third). 9% of responders singled out R-ITI as potentially good but ‘prohibitively costly’. Statistically significant predictive factors for higher rankings are familiarity with the resource (p = 0.001) and user-friendliness (p = 0.006). Conclusion: A good e-learning system will complement on-the-job training with a broad case base, deep discussion and quality trainee evaluation. Based on our study on twelve e-learning resources, no single program fulfilled all requirements. The perception and use of radiology e-learning resources depended more on familiarity and user-friendliness than on content differences and testing capability.

Keywords: e-learning, medicine, radiology, survey

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2669 Analysis of Process Methane Hydrate Formation That Include the Important Role of Deep-Sea Sediments with Analogy in Kerek Formation, Sub-Basin Kendeng, Central Java, Indonesia

Authors: Yan Bachtiar Muslih, Hangga Wijaya, Trio Fani, Putri Agustin

Abstract:

Demand of Energy in Indonesia always increases 5-6% a year, but production of conventional energy always decreases 3-5% a year, it means that conventional energy in 20-40 years ahead will not able to complete all energy demand in Indonesia, one of the solve way is using unconventional energy that is gas hydrate, gas hydrate is gas that form by biogenic process, gas hydrate stable in condition with extremely depth and low temperature, gas hydrate can form in two condition that is in pole condition and in deep-sea condition, wherein this research will focus in gas hydrate that association with methane form methane hydrate in deep-sea condition and usually form in depth between 150-2000 m, this research will focus in process of methane hydrate formation that is biogenic process and the important role of deep-sea sediment so can produce accumulation of methane hydrate, methane hydrate usually will be accumulated in find sediment in deep-sea environment with condition high-pressure and low-temperature this condition too usually make methane hydrate change into white nodule, methodology of this research is geology field work and laboratory analysis, from geology field work will get sample data consist of 10-15 samples from Kerek Formation outcrops as random for imagine the condition of deep-sea environment that influence the methane hydrate formation and also from geology field work will get data of measuring stratigraphy in outcrops Kerek Formation too from this data will help to imagine the process in deep-sea sediment like energy flow, supply sediment, and etc, and laboratory analysis is activity to analyze all data that get from geology field work, the result of this research can used to exploration activity of methane hydrate in another prospect deep-sea environment in Indonesia.

Keywords: methane hydrate, deep-sea sediment, kerek formation, sub-basin of kendeng, central java, Indonesia

Procedia PDF Downloads 446
2668 Development of Ready Reckoner Charts for Easy, Convenient, and Widespread Use of Horrock’s Apparatus by Field Level Health Functionaries in India

Authors: Gumashta Raghvendra, Gumashta Jyotsna

Abstract:

Aim and Objective of Study : The use of Horrock’s Apparatus by health care worker requires onsite mathematical calculations for estimation of ‘volume of water’ and ‘amount of bleaching powder’ necessary as per the serial number of first cup showing blue coloration after adding freshly prepared starch-iodide indicator solution. In view of the difficulties of two simultaneous calculations required to be done, the use of Horrock’s Apparatus is not routinely done by health care workers because it is impractical and inconvenient Material and Methods: Arbitrary use of bleaching powder in wells results in hyper-chlorination or hypo-chlorination of well defying the purpose of adequate chlorination or non-usage of well water due to hyper-chlorination. Keeping this in mind two nomograms have been developed, one to assess the volume of well using depth and diameter of well and the other to know the quantity of bleaching powder to b added using the number of the cup of Horrock’s apparatus which shows the colour indication. Result & Conclusion: Out of thus developed two self-speaking interlinked easy charts, first chart will facilitate bypassing requirement of formulae ‘πr2h’ for water volume (ready reckoner table with depth of water shown on ‘X’ axis and ‘diameter of well’ on ‘Y’ axis) and second chart will facilitate bypassing requirement formulae ‘2ab/455’ (where ‘a’ is for ‘serial number of cup’ and ‘b’ is for ‘water volume’, while ready reckoner table showing ‘water volume’ shown on ‘X’ axis and ‘serial number of cup’ on ‘Y’ axis). The use of these two charts will help health care worker to immediately known, by referring the two charts, about the exact requirement of bleaching powder. Thus, developed ready reckoner charts will be easy and convenient to use for ensuring prevention of water-borne diseases occurring due to hypo-chlorination, especially in rural India and other developing countries.

Keywords: apparatus, bleaching, chlorination, Horrock’s, nomogram

Procedia PDF Downloads 457
2667 Simulation of Soil-Pile Interaction of Steel Batter Piles Penetrated in Sandy Soil Subjected to Pull-Out Loads

Authors: Ameer A. Jebur, William Atherton, Rafid M. Alkhaddar, Edward Loffill

Abstract:

Superstructures like offshore platforms, tall buildings, transition towers, skyscrapers and bridges are normally designed to resist compression, uplift and lateral forces from wind waves, negative skin friction, ship impact and other applied loads. Better understanding and the precise simulation of the response of batter piles under the action of independent uplift loads is a vital topic and an area of active research in the field of geotechnical engineering. This paper investigates the use of finite element code (FEC) to examine the behaviour of model batter piles penetrated in dense sand, subjected to pull-out pressure by means of numerical modelling. The concept of the Winkler Model (beam on elastic foundation) has been used in which the interaction between the pile embedded depth and adjacent soil in the bearing zone is simulated by nonlinear p-y curves. The analysis was conducted on different pile slenderness ratios (lc⁄d) ranging from 7.5, 15.22 and 30 respectively. In addition, the optimum batter angle for a model steel pile penetrated in dense sand has been chosen to be 20° as this is the best angle for this simulation as demonstrated by other researcher published in literature. In this numerical analysis, the soil response is idealized as elasto-plastic and the model piles are described as elastic materials for the purpose of simulation. The results revealed that the applied loads affect the pullout pile capacity as well as the lateral pile response for dense sand together with varying shear strength parameters linked to the pile critical depth. Furthermore, the pile pull-out capacity increases with increasing the pile aspect ratios.

Keywords: slenderness ratio, soil-pile interaction, winkler model (beam on elastic foundation), pull-out capacity

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2666 Variation of Manning’s Coefficient in a Meandering Channel with Emergent Vegetation Cover

Authors: Spandan Sahu, Amiya Kumar Pati, Kishanjit Kumar Khatua

Abstract:

Vegetation plays a major role in deciding the flow parameters in an open channel. It enhances the aesthetic view of the revetments. The major types of vegetation in river typically comprises of herbs, grasses, weeds, trees, etc. The vegetation in an open channel usually consists of aquatic plants with complete submergence, partial submergence, floating plants. The presence of vegetative plants can have both benefits and problems. The major benefits of aquatic plants are they reduce the soil erosion, which provides the water with a free surface to move on without hindrance. The obvious problems are they retard the flow of water and reduce the hydraulic capacity of the channel. The degree to which the flow parameters are affected depends upon the density of the vegetation, degree of submergence, pattern of vegetation, vegetation species. Vegetation in open channel tends to provide resistance to flow, which in turn provides a background to study the varying trends in flow parameters having vegetative growth in the channel surface. In this paper, an experiment has been conducted on a meandering channel having sinuosity of 1.33 with rigid vegetation cover to investigate the effect on flow parameters, variation of manning’s n with degree of the denseness of vegetation, vegetation pattern and submergence criteria. The measurements have been carried out in four different cross-sections two on trough portion of the meanders, two on the crest portion. In this study, the analytical solution of Shiono and knight (SKM) for lateral distributions of depth-averaged velocity and bed shear stress have been taken into account. Dimensionless eddy viscosity and bed friction have been incorporated to modify the SKM to provide more accurate results. A mathematical model has been formulated to have a comparative analysis with the results obtained from Shiono-Knight Method.

Keywords: bed friction, depth averaged velocity, eddy viscosity, SKM

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2665 Aeromagnetic Data Interpretation and Source Body Evaluation Using Standard Euler Deconvolution Technique in Obudu Area, Southeastern Nigeria

Authors: Chidiebere C. Agoha, Chukwuebuka N. Onwubuariri, Collins U.amasike, Tochukwu I. Mgbeojedo, Joy O. Njoku, Lawson J. Osaki, Ifeyinwa J. Ofoh, Francis B. Akiang, Dominic N. Anuforo

Abstract:

In order to interpret the airborne magnetic data and evaluate the approximate location, depth, and geometry of the magnetic sources within Obudu area using the standard Euler deconvolution method, very high-resolution aeromagnetic data over the area was acquired, processed digitally and analyzed using Oasis Montaj 8.5 software. Data analysis and enhancement techniques, including reduction to the equator, horizontal derivative, first and second vertical derivatives, upward continuation and regional-residual separation, were carried out for the purpose of detailed data Interpretation. Standard Euler deconvolution for structural indices of 0, 1, 2, and 3 was also carried out and respective maps were obtained using the Euler deconvolution algorithm. Results show that the total magnetic intensity ranges from -122.9nT to 147.0nT, regional intensity varies between -106.9nT to 137.0nT, while residual intensity ranges between -51.5nT to 44.9nT clearly indicating the masking effect of deep-seated structures over surface and shallow subsurface magnetic materials. Results also indicated that the positive residual anomalies have an NE-SW orientation, which coincides with the trend of major geologic structures in the area. Euler deconvolution for all the considered structural indices has depth to magnetic sources ranging from the surface to more than 2000m. Interpretation of the various structural indices revealed the locations and depths of the source bodies and the existence of geologic models, including sills, dykes, pipes, and spherical structures. This area is characterized by intrusive and very shallow basement materials and represents an excellent prospect for solid mineral exploration and development.

Keywords: Euler deconvolution, horizontal derivative, Obudu, structural indices

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2664 GRABTAXI: A Taxi Revolution in Thailand

Authors: Danuvasin Charoen

Abstract:

The study investigates the business process and business model of GRABTAXI. The paper also discusses how the company implemented strategies to gain competitive advantages. The data is derived from the analysis of secondary data and the in-depth interviews among staffs, taxi drivers, and key customers. The findings indicated that the company’s competitive advantages come from being the first mover, emphasising on the ease of use and tangible benefits of application, and using network effect strategy.

Keywords: taxi, mobile application, innovative business model, Thailand

Procedia PDF Downloads 281
2663 Evaluation of Golden Beam Data for the Commissioning of 6 and 18 MV Photons Beams in Varian Linear Accelerator

Authors: Shoukat Ali, Abdul Qadir Jandga, Amjad Hussain

Abstract:

Objective: The main purpose of this study is to compare the Percent Depth dose (PDD) and In-plane and cross-plane profiles of Varian Golden beam data to the measured data of 6 and 18 MV photons for the commissioning of Eclipse treatment planning system. Introduction: Commissioning of treatment planning system requires an extensive acquisition of beam data for the clinical use of linear accelerators. Accurate dose delivery require to enter the PDDs, Profiles and dose rate tables for open and wedges fields into treatment planning system, enabling to calculate the MUs and dose distribution. Varian offers a generic set of beam data as a reference data, however not recommend for clinical use. In this study, we compared the generic beam data with the measured beam data to evaluate the reliability of generic beam data to be used for the clinical purpose. Methods and Material: PDDs and Profiles of Open and Wedge fields for different field sizes and at different depths measured as per Varian’s algorithm commissioning guideline. The measurement performed with PTW 3D-scanning water phantom with semi-flex ion chamber and MEPHYSTO software. The online available Varian Golden Beam Data compared with the measured data to evaluate the accuracy of the golden beam data to be used for the commissioning of Eclipse treatment planning system. Results: The deviation between measured vs. golden beam data was in the range of 2% max. In PDDs, the deviation increases more in the deeper depths than the shallower depths. Similarly, profiles have the same trend of increasing deviation at large field sizes and increasing depths. Conclusion: Study shows that the percentage deviation between measured and golden beam data is within the acceptable tolerance and therefore can be used for the commissioning process; however, verification of small subset of acquired data with the golden beam data should be mandatory before clinical use.

Keywords: percent depth dose, flatness, symmetry, golden beam data

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2662 Empowered Women Entrepreneurs and Sustainable Rural Tourism: A Study into the Voices and Experiences of Local Women in the Sundarbans Area of Bangladesh

Authors: Jakia Rajoana

Abstract:

The aim of this paper is to examine the role of women entrepreneurs in bringing about sustainable rural tourism (SRT) development in Sundarbans area of Bangladesh. Theoretically, it draws upon empowerment and entrepreneurial marketing concepts. Women entrepreneurship development and lack of empowered women as role models is an important issue for developing economies in South Asia. Despite the substantial role women play in rural economy of Sundarbans, their contribution remains overlooked as enterprises led by them are run on an informal basis and their business acumen is not taken seriously both by their families and society at large. Studies on SRT fail to engage in sufficient depth with the term applied in this paper as ‘invisible women on the margins’ who run their enterprises with no formal training or societal/familial support. Moreover, the link between their (non) tourism enterprise and their empowerment remains under-theorized. Thus empirically, this research seeks to fill a significant gap by focusing on a considerably under-researched Sundarbans region. Methodologically, this study follows a qualitative research design using visual ethnographic approach. Participant observation, semi-structured interviews, and documentation are the primary data collection instruments in three coastal communities – Munshigonj, Burigoalini and Gabura – in the Sundarbans area. By focusing on the narratives of these under-investigated women, this work aims to provide in-depth and nuanced insights into salient issues on marginal communities experience from rural women’s perspectives. Initial findings illustrate that the Sundarbans women have low income due to no or little education. In addition, socio-cultural and religious factors also restrict the scope of their extensive contribution to workplace. In addition, physical and social violence which is a common occurrence for these women inhibits their agency and contributes to their disempowerment.

Keywords: gender, empowerment, entrepreneurial marketing, sustainable rural tourism, Sundarbans

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2661 Magnetohemodynamic of Blood Flow Having Impact of Radiative Flux Due to Infrared Magnetic Hyperthermia: Spectral Relaxation Approach

Authors: Ebenezer O. Ige, Funmilayo H. Oyelami, Joshua Olutayo-Irheren, Joseph T. Okunlola

Abstract:

Hyperthermia therapy is an adjuvant procedure during which perfused body tissues is subjected to elevated range of temperature in bid to achieve improved drug potency and efficacy of cancer treatment. While a selected class of hyperthermia techniques is shouldered on the thermal radiations derived from single-sourced electro-radiation measures, there are deliberations on conjugating dual radiation field sources in an attempt to improve the delivery of therapy procedure. This paper numerically explores the thermal effectiveness of combined infrared hyperemia having nanoparticle recirculation in the vicinity of imposed magnetic field on subcutaneous strata of a model lesion as ablation scheme. An elaborate Spectral relaxation method (SRM) was formulated to handle equation of coupled momentum and thermal equilibrium in the blood-perfused tissue domain of a spongy fibrous tissue. Thermal diffusion regimes in the presence of external magnetic field imposition were described leveraging on the renowned Roseland diffusion approximation to delineate the impact of radiative flux within the computational domain. The contribution of tissue sponginess was examined using mechanics of pore-scale porosity over a selected of clinical informed scenarios. Our observations showed for a substantial depth of spongy lesion, magnetic field architecture constitute the control regimes of hemodynamics in the blood-tissue interface while facilitating thermal transport across the depth of the model lesion. This parameter-indicator could be utilized to control the dispensing of hyperthermia treatment in intravenous perfused tissue.

Keywords: spectra relaxation scheme, thermal equilibrium, Roseland diffusion approximation, hyperthermia therapy

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2660 Project-Based Learning in Engineering Education

Authors: M. Greeshma, V. Ashvini, P. Jayarekha

Abstract:

Project based learning (PBL) is a student-driven educational framework and offers the student an opportunity for in-depth investigations of courses. This paper presents the need of PBL in engineering education for the student to graduate with a capacity to design and implement complex problems. The implementation strategy of PBL and its related challenges are presented. The case study that energizes the engineering curriculum with a relevance to the real-world of technology along with its benefits to the students is also included.

Keywords: PBL, engineering education, curriculum, implement complex

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2659 Study on the Wave Dissipation Performance of Double-Cylinder and Double-Plate Floating Breakwater

Authors: Liu Bijin

Abstract:

Floating breakwaters have several advantages, including being environmentally friendly, easy to construct, and cost-effective regardless of water depth. They have a broad range of applications in coastal engineering. However, they face significant challenges due to the unstable effect of wave dissipation, structural vulnerability, and high mooring system requirements. This paper investigates the wave dissipation performance of a floating breakwater structure. The structure consists of double cylinders, double vertical plates, and horizontal connecting plates. The investigation is carried out using physical model tests and numerical simulation methods based on STAR-CCM+. This paper discusses the impact of wave elements, relative vertical plate heights, and relative horizontal connecting plate widths on the wave dissipation performance of the double-cylinder, double-plate floating breakwater (DCDPFB). The study also analyses the changes in local vorticity and velocity fields around the DCDPFB to determine the optimal structural dimensions. The study found that the relative width of the horizontal connecting plate, the relative height of the vertical plate, and the size of the semi-cylinder are the key factors affecting the wave dissipation performance of the DCDPFB. The transmittance coefficient is minimally affected by the wave height and the depth of water entry. The local vortex and velocity field formed around the DCDPFB are important factors for dissipating wave energy. The test section of the DCDPFB, constructed according to the relative optimal structural dimensions, showed good wave dissipation performance during offshore prototype tests. The test section of DCDPFB, constructed with optimal structural dimensions, exhibits excellent wave dissipation performance in offshore prototype tests.

Keywords: floating breakwater, wave dissipation performance, transmittance coefficient, model test

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2658 An Agent-Based Approach to Examine Interactions of Firms for Investment Revival

Authors: Ichiro Takahashi

Abstract:

One conundrum that macroeconomic theory faces is to explain how an economy can revive from depression, in which the aggregate demand has fallen substantially below its productive capacity. This paper examines an autonomous stabilizing mechanism using an agent-based Wicksell-Keynes macroeconomic model. This paper focuses on the effects of the number of firms and the length of the gestation period for investment that are often assumed to be one in a mainstream macroeconomic model. The simulations found the virtual economy was highly unstable, or more precisely, collapsing when these parameters are fixed at one. This finding may even suggest us to question the legitimacy of these common assumptions. A perpetual decline in capital stock will eventually encourage investment if the capital stock is short-lived because an inactive investment will result in insufficient productive capacity. However, for an economy characterized by a roundabout production method, a gradual decline in productive capacity may not be able to fall below the aggregate demand that is also shrinking. Naturally, one would then ask if our economy cannot rely on an external stimulus such as population growth and technological progress to revive investment, what factors would provide such a buoyancy for stimulating investments? The current paper attempts to answer this question by employing the artificial macroeconomic model mentioned above. The baseline model has the following three features: (1) the multi-period gestation for investment, (2) a large number of heterogeneous firms, (3) demand-constrained firms. The instability is a consequence of the following dynamic interactions. (a) A multiple-period gestation period means that once a firm starts a new investment, it continues to invest over some subsequent periods. During these gestation periods, the excess demand created by the investing firm will spill over to ignite new investment of other firms that are supplying investment goods: the presence of multi-period gestation for investment provides a field for investment interactions. Conversely, the excess demand for investment goods tends to fade away before it develops into a full-fledged boom if the gestation period of investment is short. (b) A strong demand in the goods market tends to raise the price level, thereby lowering real wages. This reduction of real wages creates two opposing effects on the aggregate demand through the following two channels: (1) a reduction in the real labor income, and (2) an increase in the labor demand due to the principle of equality between the marginal labor productivity and real wage (referred as the Walrasian labor demand). If there is only a single firm, a lower real wage will increase its Walrasian labor demand, thereby an actual labor demand tends to be determined by the derived labor demand. Thus, the second positive effect would not work effectively. In contrast, for an economy with a large number of firms, Walrasian firms will increase employment. This interaction among heterogeneous firms is a key for stability. A single firm cannot expect the benefit of such an increased aggregate demand from other firms.

Keywords: agent-based macroeconomic model, business cycle, demand constraint, gestation period, representative agent model, stability

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2657 Acoustic Emission for Tool-Chip Interface Monitoring during Orthogonal Cutting

Authors: D. O. Ramadan, R. S. Dwyer-Joyce

Abstract:

The measurement of the interface conditions in a cutting tool contact is essential information for performance monitoring and control. This interface provides the path for the heat flux to the cutting tool. This elevate in the cutting tool temperature leads to motivate the mechanism of tool wear, thus affect the life of the cutting tool and the productivity. This zone is representative by the tool-chip interface. Therefore, understanding and monitoring this interface is considered an important issue in machining. In this paper, an acoustic emission (AE) technique was used to find the correlation between AE parameters and the tool-chip interface. For this reason, a response surface design (RSD) has been used to analyse and optimize the machining parameters. The experiment design was based on the face centered, central composite design (CCD) in the Minitab environment. According to this design, a series of orthogonal cutting experiments for different cutting conditions were conducted on a Triumph 2500 lathe machine to study the sensitivity of the acoustic emission (AE) signal to change in tool-chip contact length. The cutting parameters investigated were the cutting speed, depth of cut, and feed and the experiments were performed for 6082-T6 aluminium tube. All the orthogonal cutting experiments were conducted unlubricated. The tool-chip contact area was investigated using a scanning electron microscope (SEM). The results obtained in this paper indicate that there is a strong dependence of the root mean square (RMS) on the cutting speed, where the RMS increases with increasing the cutting speed. A dependence on the tool-chip contact length has been also observed. However there was no effect observed of changing the cutting depth and feed on the RMS. These dependencies have been clarified in terms of the strain and temperature in the primary and secondary shear zones, also the tool-chip sticking and sliding phenomenon and the effect of these mechanical variables on dislocation activity at high strain rates. In conclusion, the acoustic emission technique has the potential to monitor in situ the tool-chip interface in turning and consequently could indicate the approaching end of life of a cutting tool.

Keywords: Acoustic emission, tool-chip interface, orthogonal cutting, monitoring

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2656 Analytical Study of Flexural Strength of Concrete-Filled Steel Tube Beams

Authors: Maru R., Singh V. P.

Abstract:

In this research, analytical study of the flexural strength of Concrete Filled Steel Tube (CFST) beams is carried out based on wide-range finite element models to obtain the better perspective for flexural strength achievement with the use of ABAQUS finite element program. This work adopts concrete damaged plasticity model to get the actual simulation of CFST under bending. To get the decent interaction between concrete and steel, normal and tangential surface interaction provided by ABAQUS is used with hard contact for normal surface interaction and for 0.65 friction coefficient for tangential surface interactions. In this study, rectangular and square CFST beam model cross-sections are adopted with its limits pertained to Eurocode specifications. To get the visualization for flexural strength of CFST beams, total of 74 rectangular CFST beams and 86 square CFST beams are used with four-point bending test setup and the length of the beam model as 1000mm. The grades of concrete and grades of steel are used as 30 MPa & 35MPa and 235 MPa and 275MPa respectively for both sections to get the confinement factor 0.583 to 2.833, steel ratio of 0.069 to 0.236 and length to depth ratio of 4.167 to 16.667. It was found based on this study that flexural strength of CFST beams falls around strain of 0.012. Eurocode provides the results harmonically with finite elemental results. It was also noted for square sections that reduction of steel ratio is not useful as compared to rectangular section although it increases moment capacity up to certain limits because for square sectional area similar to that of rectangular, it possesses lesser depth than rectangular sections. Also It can be said that effect of increment of grade of concrete can be achieved when thicker steel tube is present. It is observed that there is less increment in moment capacity initially but after D/b ratio 1.2, moment capacity of CFST beam rapidly.

Keywords: ABAQUS, CFST beams, flexural strength, four-point bending, rectangular and square sections

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2655 Basic Business-Forces behind the Surviving and Sustainable Organizations: The Case of Medium Scale Contractors in South Africa

Authors: Iruka C. Anugwo, Winston M. Shakantu

Abstract:

The objective of this study is to uncover the basic business-forces that necessitated the survival and sustainable performance of the medium scale contractors in the South African construction market. This study is essential as it set to contribute towards long-term strategic solutions for combating the incessant failure of start-ups construction organizations within South African. The study used a qualitative research methodology; as the most appropriate approach to elicit and understand, and uncover the phenomena that are basic business-forces for the active contractors in the market. The study also adopted a phenomenological study approach; and in-depth interviews were conducted with 20 medium scale contractors in Port Elizabeth, South Africa, between months of August to October 2015. This allowed for an in-depth understanding of the critical and basic business-forces that influenced their survival and performance beyond the first five years of business operation. Findings of the study showed that for potential contractors (startups), to survival in the competitive business environment such as construction industry, they must possess the basic business-forces. These forces are educational knowledge in construction and business management related disciplines, adequate industrial experiences, competencies and capabilities to delivery excellent services and products as well as embracing the spirit of entrepreneurship. Convincingly, it can be concluded that the strategic approach to minimize the endless failure of startups construction businesses; the potential construction contractors must endeavoring to access and acquire the basic educationally knowledge, training and qualification; need to acquire industrial experiences in collaboration with required competencies, capabilities and entrepreneurship acumen. Without these basic business-forces as been discovered in this study, the majority of the contractors gaining entrance in the market will find it difficult to develop and grow a competitive and sustainable construction organization in South Africa.

Keywords: basic business-forces, medium scale contractors, South Africa, sustainable organisations

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2654 The Tramway in French Cities: Complication of Public Spaces and Complexity of the Design Process

Authors: Elisa Maître

Abstract:

The redeployment of tram networks in French cities has considerably modified public spaces and the way citizens use them. Above and beyond the image that trams have of contributing to the sustainable urban development, the question of safety for users in these spaces has not been studied much. This study is based on an analysis of use of public spaces laid out for trams, from the standpoint of legibility and safety concerns. The study also examines to what extent the complexity of the design process, with many interactions between numerous and varied players in this process has a role in the genesis of these problems. This work is mainly based on the analysis of links between the uses of these re-designed public spaces (through observations, interviews of users and accident studies) and the analysis of the design conditions and processes of the projects studied (mainly based on interviews with the actors of these projects). Practical analyses were based three points of view: that of the planner, that of the user (based on observations and interviews) and that of the road safety expert. The cities of Montpellier, Marseille and Nice are the three fields of study on which the demonstration of this thesis is based. On part, the results of this study allow showing that the insertion of tram poses some problems complication of public areas of French cities. These complications related to the restructuring of public spaces for the tram, create difficulties of use and safety concerns. On the other hand, interviews depth analyses, fully transcribed, have led us to develop particular dysfunction scenarios in the design process. These elements lead to question the way the legibility and safety of these new forms of public spaces are taken into account. Then, an in-depth analysis of the design processes of public spaces with trams systems would also be a way of better understanding the choices made, the compromises accepted, and the conflicts and constraints at work, weighing on the layout of these spaces. The results presented concerning the impact that spaces laid out for trams have on the difficulty of use, suggest different possibilities for improving the way in which safety for all users is taken into account in designing public spaces.

Keywords: public spaces, road layout, users, design process of urban projects

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2653 Numerical Investigation on Anchored Sheet Pile Quay Wall with Separated Relieving Platform

Authors: Mahmoud Roushdy, Mohamed El Naggar, Ahmed Yehia Abdelaziz

Abstract:

Anchored sheet pile has been used worldwide as front quay walls for decades. With the increase in vessel drafts and weights, those sheet pile walls need to be upgraded by increasing the depth of the dredging line in front of the wall. A system has recently been used to increase the depth in front of the wall by installing a separated platform supported on a deep foundation (so called Relieving Platform) behind the sheet pile wall. The platform is structurally separated from the front wall. This paper presents a numerical investigation utilizing finite element analysis on the behavior of separated relieve platforms installed within existing anchored sheet pile quay walls. The investigation was done in two steps: a verification step followed by a parametric study. In the verification step, the numerical model was verified based on field measurements performed by others. The validated model was extended within the parametric study to a series of models with different backfill soils, separation gap width, and number of pile rows supporting the platform. The results of the numerical investigation show that using stiff clay as backfill soil (neglecting consolidation) gives better performance for the front wall and the first pile row adjacent to sandy backfills. The degree of compaction of the sandy backfill slightly increases lateral deformations but reduces bending moment acting on pile rows, while the effect is minor on the front wall. In addition, the increase in the separation gap width gradually increases bending moments on the front wall regardless of the backfill soil type, while this effect is reversed on pile rows (gradually decrease). Finally, the paper studies the possibility of reducing the number of pile rows along with the separation to take advantage of the positive separation effect on piles.

Keywords: anchored sheet pile, relieving platform, separation gap, upgrade quay wall

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2652 Predicting Open Chromatin Regions in Cell-Free DNA Whole Genome Sequencing Data by Correlation Clustering  

Authors: Fahimeh Palizban, Farshad Noravesh, Amir Hossein Saeidian, Mahya Mehrmohamadi

Abstract:

In the recent decade, the emergence of liquid biopsy has significantly improved cancer monitoring and detection. Dying cells, including those originating from tumors, shed their DNA into the blood and contribute to a pool of circulating fragments called cell-free DNA. Accordingly, identifying the tissue origin of these DNA fragments from the plasma can result in more accurate and fast disease diagnosis and precise treatment protocols. Open chromatin regions are important epigenetic features of DNA that reflect cell types of origin. Profiling these features by DNase-seq, ATAC-seq, and histone ChIP-seq provides insights into tissue-specific and disease-specific regulatory mechanisms. There have been several studies in the area of cancer liquid biopsy that integrate distinct genomic and epigenomic features for early cancer detection along with tissue of origin detection. However, multimodal analysis requires several types of experiments to cover the genomic and epigenomic aspects of a single sample, which will lead to a huge amount of cost and time. To overcome these limitations, the idea of predicting OCRs from WGS is of particular importance. In this regard, we proposed a computational approach to target the prediction of open chromatin regions as an important epigenetic feature from cell-free DNA whole genome sequence data. To fulfill this objective, local sequencing depth will be fed to our proposed algorithm and the prediction of the most probable open chromatin regions from whole genome sequencing data can be carried out. Our method integrates the signal processing method with sequencing depth data and includes count normalization, Discrete Fourie Transform conversion, graph construction, graph cut optimization by linear programming, and clustering. To validate the proposed method, we compared the output of the clustering (open chromatin region+, open chromatin region-) with previously validated open chromatin regions related to human blood samples of the ATAC-DB database. The percentage of overlap between predicted open chromatin regions and the experimentally validated regions obtained by ATAC-seq in ATAC-DB is greater than 67%, which indicates meaningful prediction. As it is evident, OCRs are mostly located in the transcription start sites (TSS) of the genes. In this regard, we compared the concordance between the predicted OCRs and the human genes TSS regions obtained from refTSS and it showed proper accordance around 52.04% and ~78% with all and the housekeeping genes, respectively. Accurately detecting open chromatin regions from plasma cell-free DNA-seq data is a very challenging computational problem due to the existence of several confounding factors, such as technical and biological variations. Although this approach is in its infancy, there has already been an attempt to apply it, which leads to a tool named OCRDetector with some restrictions like the need for highly depth cfDNA WGS data, prior information about OCRs distribution, and considering multiple features. However, we implemented a graph signal clustering based on a single depth feature in an unsupervised learning manner that resulted in faster performance and decent accuracy. Overall, we tried to investigate the epigenomic pattern of a cell-free DNA sample from a new computational perspective that can be used along with other tools to investigate genetic and epigenetic aspects of a single whole genome sequencing data for efficient liquid biopsy-related analysis.

Keywords: open chromatin regions, cancer, cell-free DNA, epigenomics, graph signal processing, correlation clustering

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