Search results for: critical parameters
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 13186

Search results for: critical parameters

796 Force Sensor for Robotic Graspers in Minimally Invasive Surgery

Authors: Naghmeh M. Bandari, Javad Dargahi, Muthukumaran Packirisamy

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Robot-assisted minimally invasive surgery (RMIS) has been widely performed around the world during the last two decades. RMIS demonstrates significant advantages over conventional surgery, e.g., improving the accuracy and dexterity of a surgeon, providing 3D vision, motion scaling, hand-eye coordination, decreasing tremor, and reducing x-ray exposure for surgeons. Despite benefits, surgeons cannot touch the surgical site and perceive tactile information. This happens due to the remote control of robots. The literature survey identified the lack of force feedback as the riskiest limitation in the existing technology. Without the perception of tool-tissue contact force, the surgeon might apply an excessive force causing tissue laceration or insufficient force causing tissue slippage. The primary use of force sensors has been to measure the tool-tissue interaction force in real-time in-situ. Design of a tactile sensor is subjected to a set of design requirements, e.g., biocompatibility, electrical-passivity, MRI-compatibility, miniaturization, ability to measure static and dynamic force. In this study, a planar optical fiber-based sensor was proposed to mount at the surgical grasper. It was developed based on the light intensity modulation principle. The deflectable part of the sensor was a beam modeled as a cantilever Euler-Bernoulli beam on rigid substrates. A semi-cylindrical indenter was attached to the bottom surface the beam at the mid-span. An optical fiber was secured at both ends on the same rigid substrates. The indenter was in contact with the fiber. External force on the sensor caused deflection in the beam and optical fiber simultaneously. The micro-bending of the optical fiber would consequently result in light power loss. The sensor was simulated and studied using finite element methods. A laser light beam with 800nm wavelength and 5mW power was used as the input to the optical fiber. The output power was measured using a photodetector. The voltage from photodetector was calibrated to the external force for a chirp input (0.1-5Hz). The range, resolution, and hysteresis of the sensor were studied under monotonic and harmonic external forces of 0-2.0N with 0 and 5Hz, respectively. The results confirmed the validity of proposed sensing principle. Also, the sensor demonstrated an acceptable linearity (R2 > 0.9). A minimum external force was observed below which no power loss was detectable. It is postulated that this phenomenon is attributed to the critical angle of the optical fiber to observe total internal reflection. The experimental results were of negligible hysteresis (R2 > 0.9) and in fair agreement with the simulations. In conclusion, the suggested planar sensor is assessed to be a cost-effective solution, feasible, and easy to use the sensor for being miniaturized and integrated at the tip of robotic graspers. Geometrical and optical factors affecting the minimum sensible force and the working range of the sensor should be studied and optimized. This design is intrinsically scalable and meets all the design requirements. Therefore, it has a significant potential of industrialization and mass production.

Keywords: force sensor, minimally invasive surgery, optical sensor, robotic surgery, tactile sensor

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795 Promotion of Healthy Food Choices in School Children through Nutrition Education

Authors: Vinti Davar

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Introduction: Childhood overweight increases the risk for certain medical and psychological conditions. Millions of school-age children worldwide are affected by serious yet easily treatable and preventable illnesses that inhibit their ability to learn. Healthier children stay in school longer, attend more regularly, learn more and become healthier and more productive adults. Schools are an important setting for nutrition education because one can reach most children, teachers and parents. These years offer a key window for shaping their lifetime habits, which have an impact on their health throughout life. Against this background, an attempt was made to impart nutrition education to school children in Haryana state of India to promote healthy food choices and assess the effectiveness of this program. Methodology: This study was completed in two phases. During the first phase, pre-intervention anthropometric and dietary survey was conducted; the teaching materials for nutrition intervention program were developed and tested; and the questionnaire was validated. In the second phase, an intervention was implemented in two schools of Kurukshetra, Haryana for six months by personal visits once a week. A total of 350 children in the age group of 6-12 years were selected. Out of these, 279 children, 153 boys and 126 girls completed the study. The subjects were divided into four groups namely: underweight, normal, overweight and obese based on body mass index-for-age categories. A power point colorful presentation to improve the quality of tiffin, snacks and meals emphasizing inclusion of all food groups especially vegetables every day and fruits at least 3-4 days per week was used. An extra 20 minutes of aerobic exercise daily was likewise organized and a healthy school environment created. Provision of clean drinking water by school authorities was ensured. Selling of soft drinks and energy-dense snacks in the school canteen as well as advertisements about soft drink and snacks on the school walls were banned. Post intervention, anthropometric indices and food selections were reassessed. Results: The results of this study reiterate the critical role of nutrition education and promotion in improving the healthier food choices by school children. It was observed that normal, overweight and obese children participating in nutrition education intervention program significantly (p≤0.05) increased their daily seasonal fruit and vegetable consumption. Fat and oil consumption was significantly reduced by overweight and obese subjects. Fast food intake was controlled by obese children. The nutrition knowledge of school children significantly improved (p≤0.05) from pre to post intervention. A highly significant increase (p≤0.00) was noted in the nutrition attitude score after intervention in all four groups. Conclusion: This study has shown that a well-planned nutrition education program could improve nutrition knowledge and promote positive changes in healthy food choices. A nutrition program inculcates wholesome eating and active life style habits in children and adolescents that could not only prevent them from chronic diseases and early death but also reduce healthcare cost and enhance the quality of life of citizens and thereby nations.

Keywords: children, eating habits healthy food, obesity, school going, fast foods

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794 Study of Open Spaces in Urban Residential Clusters in India

Authors: Renuka G. Oka

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From chowks to streets to verandahs to courtyards; residential open spaces are very significantly placed in traditional urban neighborhoods of India. At various levels of intersection, the open spaces with their attributes like juxtaposition with the built fabric, scale, climate sensitivity and response, multi-functionality, etc. reflect and respond to the patterns of human interactions. Also, these spaces tend to be quite well utilized. On the other hand, it is a common specter to see an imbalanced utilization of open spaces in newly/recently planned residential clusters. This is maybe due to lack of activity generators around or wrong locations or excess provisions or improper incorporation of aforementioned design attributes. These casual observations suggest the necessity for a systematic study of current residential open spaces. The exploratory study thus attempts to draw lessons through a structured inspection of residential open spaces to understand the effective environment as revealed through their use patterns. Here, residential open spaces are considered in a wider sense to incorporate all the un-built fabric around. These thus, include both use spaces and access space. For the study, open spaces in ten exemplary housing clusters/societies built during the last ten years across India are studied. A threefold inquiry is attempted in this direction. The first relates to identifying and determining the effects of various physical functions like space organization, size, hierarchy, thermal and optical comfort, etc. on the performance of residential open spaces. The second part sets out to understand socio-cultural variations in values, lifestyle, and beliefs which determine activity choices and behavioral preferences of users for respective residential open spaces. The third inquiry further observes the application of these research findings to the design process to derive meaningful and qualitative design advice. However, the study also emphasizes to develop a suitable framework of analysis and to carve out appropriate methods and approaches to probe into these aspects of the inquiry. Given this emphasis, a considerable portion of the research details out the conceptual framework for the study. This framework is supported by an in-depth search of available literature. The findings are worked out for design solutions which integrate the open space systems with the overall design process for residential clusters. The open spaces in residential areas present great complexities both in terms of their use patterns and determinants of their functional responses. The broad aim of the study is, therefore, to arrive at reconsideration of standards and qualitative parameters used by designers – on the basis of more substantial inquiry into the use patterns of open spaces in residential areas.

Keywords: open spaces, physical and social determinants, residential clusters, use patterns

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793 Sustainability Communications Across Multi-Stakeholder Groups: A Critical Review of the Findings from the Hospitality and Tourism Sectors

Authors: Frederica Pettit

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Contribution: Stakeholder involvement in CSR is essential to ensuring pro-environmental attitudes and behaviours across multi-stakeholder groups. Despite increased awareness of the benefits surrounding a collaborative approach to sustainability communications, its success is limited by difficulties engaging with active online conversations with stakeholder groups. Whilst previous research defines the effectiveness of sustainability communications; this paper contributes to knowledge through the development of a theoretical framework that explores the processes to achieving pro-environmental attitudes and behaviours in stakeholder groups. The research will also consider social media as an opportunity to communicate CSR information to all stakeholder groups. Approach: A systematic review was chosen to investigate the effectiveness of the types of sustainability communications used in the hospitality and tourism industries. The systematic review was completed using Web of Science and Scopus using the search terms “sustainab* communicat*” “effective or effectiveness,” and “hospitality or tourism,” limiting the results to peer-reviewed research. 133 abstracts were initially read, with articles being excluded for irrelevance, duplicated articles, non-empirical studies, and language. A total of 45 papers were included as part of the systematic review. 5 propositions were created based on the results of the systematic review, helping to develop a theoretical framework of the processes needed for companies to encourage pro-environmental behaviours across multi-stakeholder groups. Results: The theoretical framework developed in the paper determined the processes necessary for companies to achieve pro-environmental behaviours in stakeholders. The processes to achieving pro-environmental attitudes and behaviours are stakeholder-focused, identifying the need for communications to be specific to their targeted audience. Collaborative communications that enable stakeholders to engage with CSR information and provide feedback lead to a higher awareness of CSR shared visions and pro-environmental attitudes and behaviours. These processes should also aim to improve their relationships with stakeholders through transparency of CSR, CSR strategies that match stakeholder values and ethics whilst prioritizing sustainability as part of their job role. Alternatively, companies can prioritize pro-environmental behaviours using choice editing by mainstreaming sustainability as the only option. In recent years, there has been extensive research on social media as a viable source of sustainability communications, with benefits including direct interactions with stakeholders, the ability to enforce the authenticity of CSR activities and encouragement of pro-environmental behaviours. Despite this, there are challenges to implementing CSR, including difficulties controlling stakeholder criticisms, negative stakeholder influences and comments left on social media platforms. Conclusion: A lack of engagement with CSR information is a reoccurring reason for preventing pro-environmental attitudes and behaviours across stakeholder groups. Traditional CSR strategies contribute to this due to their inability to engage with their intended audience. Hospitality and tourism companies are improving stakeholder relationships through collaborative processes which reduce single-use plastic consumption. A collaborative approach to communications can lead to stakeholder satisfaction, leading to changes in attitudes and behaviours. Different sources of communications are accessed by different stakeholder groups, identifying the need for targeted sustainability messaging, creating benefits such as direct interactions with stakeholders, the ability to enforce the authenticity of CSR activities, and encouraging engagement with sustainability information.

Keywords: hospitality, pro-environmental attitudes and behaviours, sustainability communication, social media

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792 Assessment of Soil Quality Indicators in Rice Soils Under Rainfed Ecosystem

Authors: R. Kaleeswari

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An investigation was carried out to assess the soil biological quality parameters in rice soils under rainfed and to compare soil quality indexing methods viz., Principal component analysis, Minimum data set and Indicator scoring method and to develop soil quality indices for formulating soil and crop management strategies.Soil samples were collected and analyzed for soil biological properties by adopting standard procedure. Biological indicators were determined for soil quality assessment, viz., microbial biomass carbon and nitrogen (MBC and MBN), potentially mineralizable nitrogen (PMN) and soil respiration and dehydrogenease activity. Among the methods of rice cultivation, Organic nutrition, Integrated Nutrient Management (INM) and System of Rice Intensification (SRI ), rice cultivation registered higher values of MBC, MBN and PMN. Mechanical and conventional rice cultivation registered lower values of biological quality indicators. Organic nutrient management and INM enhanced the soil respiration rate. SRI and aerobic rice cultivation methods increased the rate of soil respiration, while conventional and mechanical rice farming lowered the soil respiration rate. Dehydrogenase activity (DHA) was registered to be higher in soils under organic nutrition and Integrated Nutrient Management INM. System of Rice Intensification SRI and aerobic rice cultivation enhanced the DHA; while conventional and mechanical rice cultivation methods reduced DHA. The microbial biomass carbon (MBC) of the rice soils varied from 65 to 244 mg kg-1. Among the nutrient management practices, INM registered the highest available microbial biomass carbon of 285 mg kg-1.Potentially mineralizable N content of the rice soils varied from 20.3 to 56.8 mg kg-1. Aerobic rice farming registered the highest potentially mineralizable N of 78.9 mg kg-1..The soil respiration rate of the rice soils varied from 60 to 125 µgCO2 g-1. Nutrient management practices ofINM practice registered the highest. soil respiration rate of 129 µgCO2 g-1.The dehydrogenase activity of the rice soils varied from 38.3 to 135.3µgTPFg-1 day-1. SRI method of rice cultivation registered the highest dehydrogenase activity of 160.2 µgTPFg-1 day-1. Soil variables from each PC were considered for minimum soil data set (MDS). Principal component analysis (PCA) was used to select the representative soil quality indicators. In intensive rice cultivating regions, soil quality indicators were selected based on factor loading value and contribution percentage value using principal component analysis (PCA).Variables having significant difference within production systems were used for the preparation of minimum data set (MDS).

Keywords: soil quality, rice, biological properties, PCA analysis

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791 Role of Zinc Adminstration in Improvement of Faltering Growth in Egyption Children at Risk of Environmental Enteric Dysfunction

Authors: Ghada Mahmoud El Kassas, Maged Atta El Wakeel

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Background: Environmental enteric dysfunction (EED) is impending trouble that flared up in the last decades to be pervasive in infants and children. EED is asymptomatic villous atrophy of the small bowel that is prevalent in the developing world and is associated with altered intestinal function and integrity. Evidence has suggested that supplementary zinc might ameliorate this damage by reducing gastrointestinal inflammation and may also benefit cognitive development. Objective: We tested whether zinc supplementation improves intestinal integrity, growth, and cognitive function in stunted children predicted to have EED. Methodology: This case–control prospective interventional study was conducted on 120 Egyptian Stunted children aged 1-10 years who recruited from the Nutrition clinic, the National research center, and 100 age and gender-matched healthy children as controls. At the primary phase of the study, Full history taking, clinical examination, and anthropometric measurements were done. Standard deviation score (SDS) for all measurements were calculated. Serum markers as Zonulin, Endotoxin core antibody (EndoCab), highly sensitive C-reactive protein (hsCRP), alpha1-acid glycoprotein (AGP), Tumor necrosis factor (TNF), and fecal markers such as myeloperoxidase (MPO), neopterin (NEO), and alpha-1-anti-trypsin (AAT) (as predictors of EED) were measured. Cognitive development was assessed (Bayley or Wechsler scores). Oral zinc at a dosage of 20 mg/d was supplemented to all cases and followed up for 6 months, after which the 2ry phase of the study included the previous clinical, laboratory, and cognitive assessment. Results: Serum and fecal inflammatory markers were significantly higher in cases compared to controls. Zonulin (P < 0.01), (EndoCab) (P < 0.001) and (AGP) (P < 0.03) markedly decreased in cases at the end of 2ry phase. Also (MPO), (NEO), and (AAT) showed a significant decline in cases at the end of the study (P < 0.001 for all). A significant increase in mid-upper arm circumference (MUAC) (P < 0.01), weight for age z-score, and skinfold thicknesses (P< 0.05 for both) was detected at end of the study, while height was not significantly affected. Cases also showed significant improvement of cognitive function at phase 2 of the study. Conclusion: Intestinal inflammatory state related to EED showed marked recovery after zinc supplementation. As a result, anthropometric and cognitive parameters showed obvious improvement with zinc supplementation.

Keywords: stunting, cognitive function, environmental enteric dysfunction, zinc

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790 Heat Transfer Dependent Vortex Shedding of Thermo-Viscous Shear-Thinning Fluids

Authors: Markus Rütten, Olaf Wünsch

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Non-Newtonian fluid properties can change the flow behaviour significantly, its prediction is more difficult when thermal effects come into play. Hence, the focal point of this work is the wake flow behind a heated circular cylinder in the laminar vortex shedding regime for thermo-viscous shear thinning fluids. In the case of isothermal flows of Newtonian fluids the vortex shedding regime is characterised by a distinct Reynolds number and an associated Strouhal number. In the case of thermo-viscous shear thinning fluids the flow regime can significantly change in dependence of the temperature of the viscous wall of the cylinder. The Reynolds number alters locally and, consequentially, the Strouhal number globally. In the present CFD study the temperature dependence of the Reynolds and Strouhal number is investigated for the flow of a Carreau fluid around a heated cylinder. The temperature dependence of the fluid viscosity has been modelled by applying the standard Williams-Landel-Ferry (WLF) equation. In the present simulation campaign thermal boundary conditions have been varied over a wide range in order to derive a relation between dimensionless heat transfer, Reynolds and Strouhal number. Together with the shear thinning due to the high shear rates close to the cylinder wall this leads to a significant decrease of viscosity of three orders of magnitude in the nearfield of the cylinder and a reduction of two orders of magnitude in the wake field. Yet the shear thinning effect is able to change the flow topology: a complex K´arm´an vortex street occurs, also revealing distinct characteristic frequencies associated with the dominant and sub-dominant vortices. Heating up the cylinder wall leads to a delayed flow separation and narrower wake flow, giving lesser space for the sequence of counter-rotating vortices. This spatial limitation does not only reduce the amplitude of the oscillating wake flow it also shifts the dominant frequency to higher frequencies, furthermore it damps higher harmonics. Eventually the locally heated wake flow smears out. Eventually, the CFD simulation results of the systematically varied thermal flow parameter study have been used to describe a relation for the main characteristic order parameters.

Keywords: heat transfer, thermo-viscous fluids, shear thinning, vortex shedding

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789 Chromium (VI) Removal from Aqueous Solutions by Ion Exchange Processing Using Eichrom 1-X4, Lewatit Monoplus M800 and Lewatit A8071 Resins: Batch Ion Exchange Modeling

Authors: Havva Tutar Kahraman, Erol Pehlivan

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In recent years, environmental pollution by wastewater rises very critically. Effluents discharged from various industries cause this challenge. Different type of pollutants such as organic compounds, oxyanions, and heavy metal ions create this threat for human bodies and all other living things. However, heavy metals are considered one of the main pollutant groups of wastewater. Therefore, this case creates a great need to apply and enhance the water treatment technologies. Among adopted treatment technologies, adsorption process is one of the methods, which is gaining more and more attention because of its easy operations, the simplicity of design and versatility. Ion exchange process is one of the preferred methods for removal of heavy metal ions from aqueous solutions. It has found widespread application in water remediation technologies, during the past several decades. Therefore, the purpose of this study is to the removal of hexavalent chromium, Cr(VI), from aqueous solutions. Cr(VI) is considered as a well-known highly toxic metal which modifies the DNA transcription process and causes important chromosomic aberrations. The treatment and removal of this heavy metal have received great attention to maintaining its allowed legal standards. The purpose of the present paper is an attempt to investigate some aspects of the use of three anion exchange resins: Eichrom 1-X4, Lewatit Monoplus M800 and Lewatit A8071. Batch adsorption experiments were carried out to evaluate the adsorption capacity of these three commercial resins in the removal of Cr(VI) from aqueous solutions. The chromium solutions used in the experiments were synthetic solutions. The parameters that affect the adsorption, solution pH, adsorbent concentration, contact time, and initial Cr(VI) concentration, were performed at room temperature. High adsorption rates of metal ions for the three resins were reported at the onset, and then plateau values were gradually reached within 60 min. The optimum pH for Cr(VI) adsorption was found as 3.0 for these three resins. The adsorption decreases with the increase in pH for three anion exchangers. The suitability of Freundlich, Langmuir and Scatchard models were investigated for Cr(VI)-resin equilibrium. Results, obtained in this study, demonstrate excellent comparability between three anion exchange resins indicating that Eichrom 1-X4 is more effective and showing highest adsorption capacity for the removal of Cr(VI) ions. Investigated anion exchange resins in this study can be used for the efficient removal of chromium from water and wastewater.

Keywords: adsorption, anion exchange resin, chromium, kinetics

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788 Deconstructing Reintegration Services for Survivors of Human Trafficking: A Feminist Analysis of Australian and Thai Government and Non-Government Responses

Authors: Jessica J. Gillies

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Awareness of the tragedy that is human trafficking has increased exponentially over the past two decades. The four pillars widely recognised as global solutions to the problem are prevention, prosecution, protection, and partnership between government and non-government organisations. While ‘sex-trafficking’ initially received major attention, this focus has shifted to other industries that conceal broader experiences of exploitation. However, within the regions of focus for this study, namely Australia and Thailand, trafficking for the purpose of sexual exploitation remains the commonly uncovered narrative of criminal justice investigations. In these regions anti-trafficking action is characterised by government-led prevention and prosecution efforts; whereas protection and reintegration practices have received criticism. Typically, non-government organisations straddle the critical chasm between policy and practice; therefore, they are perfectly positioned to contribute valuable experiential knowledge toward understanding how both sectors can support survivors in the post-trafficking experience. The aim of this research is to inform improved partnerships throughout government and non-government post-trafficking services by illuminating gaps in protection and reintegration initiatives. This research will explore government and non-government responses to human trafficking in Thailand and Australia, in order to understand how meaning is constructed in this context and how the construction of meaning effects survivors in the post-trafficking experience. A qualitative, three-stage methodology was adopted for this study. The initial stage of enquiry consisted of a discursive analysis, in order to deconstruct the broader discourses surrounding human trafficking. The data included empirical papers, grey literature such as publicly available government and non-government reports, and anti-trafficking policy documents. The second and third stages of enquiry will attempt to further explore the findings of the discourse analysis and will focus more specifically on protection and reintegration in Australia and Thailand. Stages two and three will incorporate process observations in government and non-government survivor support services, and semi-structured interviews with employees and volunteers within these settings. Two key findings emerged from the discursive analysis. The first exposed conflicting feminist arguments embedded throughout anti-trafficking discourse. Informed by conflicting feminist discourses on sex-work, a discursive relationship has been constructed between sex-industry policy and anti-trafficking policy. In response to this finding, data emerging from the process observations and semi-structured interviews will be interpreted using a feminist theoretical framework. The second finding progresses from the construction in the first. The discursive construction of sex-trafficking appears to have had influence over perceptions of the legitimacy of survivors, and therefore the support they receive in the post-trafficking experience. For example; women who willingly migrate for employment in the sex-industry, and on arrival are faced with exploitative conditions, are not perceived to be deserving of the same support as a woman who is not coerced, but rather physically forced, into such circumstances, yet both meet the criteria for a victim of human trafficking. The forthcoming study is intended to contribute toward building knowledge and understanding around the implications of the construction of legitimacy; and contextualise this in reference to government led protection and reintegration support services for survivors in the post-trafficking experience.

Keywords: Australia, government, human trafficking, non-government, reintegration, Thailand

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787 A Model of the Universe without Expansion of Space

Authors: Jia-Chao Wang

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A model of the universe without invoking space expansion is proposed to explain the observed redshift-distance relation and the cosmic microwave background radiation (CMB). The main hypothesized feature of the model is that photons traveling in space interact with the CMB photon gas. This interaction causes the photons to gradually lose energy through dissipation and, therefore, experience redshift. The interaction also causes some of the photons to be scattered off their track toward an observer and, therefore, results in beam intensity attenuation. As observed, the CMB exists everywhere in space and its photon density is relatively high (about 410 per cm³). The small average energy of the CMB photons (about 6.3×10⁻⁴ eV) can reduce the energies of traveling photons gradually and will not alter their momenta drastically as in, for example, Compton scattering, to totally blur the images of distant objects. An object moving through a thermalized photon gas, such as the CMB, experiences a drag. The cause is that the object sees a blue shifted photon gas along the direction of motion and a redshifted one in the opposite direction. An example of this effect can be the observed CMB dipole: The earth travels at about 368 km/s (600 km/s) relative to the CMB. In the all-sky map from the COBE satellite, radiation in the Earth's direction of motion appears 0.35 mK hotter than the average temperature, 2.725 K, while radiation on the opposite side of the sky is 0.35 mK colder. The pressure of a thermalized photon gas is given by Pγ = Eγ/3 = αT⁴/3, where Eγ is the energy density of the photon gas and α is the Stefan-Boltzmann constant. The observed CMB dipole, therefore, implies a pressure difference between the two sides of the earth and results in a CMB drag on the earth. By plugging in suitable estimates of quantities involved, such as the cross section of the earth and the temperatures on the two sides, this drag can be estimated to be tiny. But for a photon traveling at the speed of light, 300,000 km/s, the drag can be significant. In the present model, for the dissipation part, it is assumed that a photon traveling from a distant object toward an observer has an effective interaction cross section pushing against the pressure of the CMB photon gas. For the attenuation part, the coefficient of the typical attenuation equation is used as a parameter. The values of these two parameters are determined by fitting the 748 µ vs. z data points compiled from 643 supernova and 105 γ-ray burst observations with z values up to 8.1. The fit is as good as that obtained from the lambda cold dark matter (ΛCDM) model using online cosmological calculators and Planck 2015 results. The model can be used to interpret Hubble's constant, Olbers' paradox, the origin and blackbody nature of the CMB radiation, the broadening of supernova light curves, and the size of the observable universe.

Keywords: CMB as the lowest energy state, model of the universe, origin of CMB in a static universe, photon-CMB photon gas interaction

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786 The Ballistics Case Study of the Enrica Lexie Incident

Authors: Diego Abbo

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On February 15, 2012 off the Indian coast of Kerala, in position 091702N-0760180E by the oil tanker Enrica Lexie, flying the Italian flag, bursts of 5.56 x45 caliber shots were fired from assault rifles AR/70 Italian-made Beretta towards the Indian fisher boat St. Anthony. The shots that hit the St. Anthony fishing boat were six, of which two killed the Indian fishermen Ajesh Pink and Valentine Jelestine. From the analysis concerning the kinematic engagement of the two ships and from the autopsy and ballistic results of the Indian judicial authorities it is possible to reconstruct the trajectories of the six aforementioned shots. This essay reconstructs the trajectories of the six shots that cannot be of direct shooting but have undergone a rebound on the water. The investigation carried out scientifically demonstrates the rebound of the blows on the water, the gyrostatic deviation due to the rebound and the tumbling effect always due to the rebound as regards intermediate ballistics. In consideration of the four shots that directly impacted the fishing vessel, the current examination proves, with scientific value, that the trajectories could not be downwards but upwards. Also, the trajectory of two shots that hit to death the two fishermen could not be downwards but only upwards. In fact, this paper demonstrates, with scientific value: The loss of speed of the projectiles due to the rebound on the water; The tumbling effect in the ballistic medium within the two victims; The permanent cavities subject to the injury ballistics and the related ballistic trauma that prevented homeostasis causing bleeding in one case; The thermo-hardening deformation of the bullet found in Valentine Jelestine's skull; The upward and non-downward trajectories. The paper constitutes a tool in forensic ballistics in that it manages to reconstruct, from the final spot of the projectiles fired, all phases of ballistics like the internal one of the weapons that fired, the intermediate one, the terminal one and the penetrative structural one. In general terms the ballistics reconstruction is based on measurable parameters whose entity is contained with certainty within a lower and upper limit. Therefore, quantities that refer to angles, speed, impact energy and firing position of the shooter can be identified within the aforementioned limits. Finally, the investigation into the internal bullet track, obtained from any autopsy examination, offers a significant “lesson learned” but overall a starting point to contain or mitigate bleeding as a rescue from future gunshot wounds.

Keywords: impact physics, intermediate ballistics, terminal ballistics, tumbling effect

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785 Digital Holographic Interferometric Microscopy for the Testing of Micro-Optics

Authors: Varun Kumar, Chandra Shakher

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Micro-optical components such as microlenses and microlens array have numerous engineering and industrial applications for collimation of laser diodes, imaging devices for sensor system (CCD/CMOS, document copier machines etc.), for making beam homogeneous for high power lasers, a critical component in Shack-Hartmann sensor, fiber optic coupling and optical switching in communication technology. Also micro-optical components have become an alternative for applications where miniaturization, reduction of alignment and packaging cost are necessary. The compliance with high-quality standards in the manufacturing of micro-optical components is a precondition to be compatible on worldwide markets. Therefore, high demands are put on quality assurance. For quality assurance of these lenses, an economical measurement technique is needed. For cost and time reason, technique should be fast, simple (for production reason), and robust with high resolution. The technique should provide non contact, non-invasive and full field information about the shape of micro- optical component under test. The interferometric techniques are noncontact type and non invasive and provide full field information about the shape of the optical components. The conventional interferometric technique such as holographic interferometry or Mach-Zehnder interferometry is available for characterization of micro-lenses. However, these techniques need more experimental efforts and are also time consuming. Digital holography (DH) overcomes the above described problems. Digital holographic microscopy (DHM) allows one to extract both the amplitude and phase information of a wavefront transmitted through the transparent object (microlens or microlens array) from a single recorded digital hologram by using numerical methods. Also one can reconstruct the complex object wavefront at different depths due to numerical reconstruction. Digital holography provides axial resolution in nanometer range while lateral resolution is limited by diffraction and the size of the sensor. In this paper, Mach-Zehnder based digital holographic interferometric microscope (DHIM) system is used for the testing of transparent microlenses. The advantage of using the DHIM is that the distortions due to aberrations in the optical system are avoided by the interferometric comparison of reconstructed phase with and without the object (microlens array). In the experiment, first a digital hologram is recorded in the absence of sample (microlens array) as a reference hologram. Second hologram is recorded in the presence of microlens array. The presence of transparent microlens array will induce a phase change in the transmitted laser light. Complex amplitude of object wavefront in presence and absence of microlens array is reconstructed by using Fresnel reconstruction method. From the reconstructed complex amplitude, one can evaluate the phase of object wave in presence and absence of microlens array. Phase difference between the two states of object wave will provide the information about the optical path length change due to the shape of the microlens. By the knowledge of the value of the refractive index of microlens array material and air, the surface profile of microlens array is evaluated. The Sag of microlens and radius of curvature of microlens are evaluated and reported. The sag of microlens agrees well within the experimental limit as provided in the specification by the manufacturer.

Keywords: micro-optics, microlens array, phase map, digital holographic interferometric microscopy

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784 Evaluation of the Weight-Based and Fat-Based Indices in Relation to Basal Metabolic Rate-to-Weight Ratio

Authors: Orkide Donma, Mustafa M. Donma

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Basal metabolic rate is questioned as a risk factor for weight gain. The relations between basal metabolic rate and body composition have not been cleared yet. The impact of fat mass on basal metabolic rate is also uncertain. Within this context, indices based upon total body mass as well as total body fat mass are available. In this study, the aim is to investigate the potential clinical utility of these indices in the adult population. 287 individuals, aged from 18 to 79 years, were included into the scope of the study. Based upon body mass index values, 10 underweight, 88 normal, 88 overweight, 81 obese, and 20 morbid obese individuals participated. Anthropometric measurements including height (m), and weight (kg) were performed. Body mass index, diagnostic obesity notation model assessment index I, diagnostic obesity notation model assessment index II, basal metabolic rate-to-weight ratio were calculated. Total body fat mass (kg), fat percent (%), basal metabolic rate, metabolic age, visceral adiposity, fat mass of upper as well as lower extremities and trunk, obesity degree were measured by TANITA body composition monitor using bioelectrical impedance analysis technology. Statistical evaluations were performed by statistical package (SPSS) for Windows Version 16.0. Scatterplots of individual measurements for the parameters concerning correlations were drawn. Linear regression lines were displayed. The statistical significance degree was accepted as p < 0.05. The strong correlations between body mass index and diagnostic obesity notation model assessment index I as well as diagnostic obesity notation model assessment index II were obtained (p < 0.001). A much stronger correlation was detected between basal metabolic rate and diagnostic obesity notation model assessment index I in comparison with that calculated for basal metabolic rate and body mass index (p < 0.001). Upon consideration of the associations between basal metabolic rate-to-weight ratio and these three indices, the best association was observed between basal metabolic rate-to-weight and diagnostic obesity notation model assessment index II. In a similar manner, this index was highly correlated with fat percent (p < 0.001). Being independent of the indices, a strong correlation was found between fat percent and basal metabolic rate-to-weight ratio (p < 0.001). Visceral adiposity was much strongly correlated with metabolic age when compared to that with chronological age (p < 0.001). In conclusion, all three indices were associated with metabolic age, but not with chronological age. Diagnostic obesity notation model assessment index II values were highly correlated with body mass index values throughout all ranges starting with underweight going towards morbid obesity. This index is the best in terms of its association with basal metabolic rate-to-weight ratio, which can be interpreted as basal metabolic rate unit.

Keywords: basal metabolic rate, body mass index, children, diagnostic obesity notation model assessment index, obesity

Procedia PDF Downloads 135
783 Blended Learning Instructional Approach to Teach Pharmaceutical Calculations

Authors: Sini George

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Active learning pedagogies are valued for their success in increasing 21st-century learners’ engagement, developing transferable skills like critical thinking or quantitative reasoning, and creating deeper and more lasting educational gains. 'Blended learning' is an active learning pedagogical approach in which direct instruction moves from the group learning space to the individual learning space, and the resulting group space is transformed into a dynamic, interactive learning environment where the educator guides students as they apply concepts and engage creatively in the subject matter. This project aimed to develop a blended learning instructional approach to teaching concepts around pharmaceutical calculations to year 1 pharmacy students. The wrong dose, strength or frequency of a medication accounts for almost a third of medication errors in the NHS therefore, progression to year 2 requires a 70% pass in this calculation test, in addition to the standard progression requirements. Many students were struggling to achieve this requirement in the past. It was also challenging to teach these concepts to students of a large class (> 130) with mixed mathematical abilities, especially within a traditional didactic lecture format. Therefore, short screencasts with voice-over of the lecturer were provided in advance of a total of four teaching sessions (two hours/session), incorporating core content of each session and talking through how they approached the calculations to model metacognition. Links to the screencasts were posted on the learning management. Viewership counts were used to determine that the students were indeed accessing and watching the screencasts on schedule. In the classroom, students had to apply the knowledge learned beforehand to a series of increasingly difficult set of questions. Students were then asked to create a question in group settings (two students/group) and to discuss the questions created by their peers in their groups to promote deep conceptual learning. Students were also given time for question-and-answer period to seek clarifications on the concepts covered. Student response to this instructional approach and their test grades were collected. After collecting and organizing the data, statistical analysis was carried out to calculate binomial statistics for the two data sets: the test grade for students who received blended learning instruction and the test grades for students who received instruction in a standard lecture format in class, to compare the effectiveness of each type of instruction. Student response and their performance data on the assessment indicate that the learning of content in the blended learning instructional approach led to higher levels of student engagement, satisfaction, and more substantial learning gains. The blended learning approach enabled each student to learn how to do calculations at their own pace freeing class time for interactive application of this knowledge. Although time-consuming for an instructor to implement, the findings of this research demonstrate that the blended learning instructional approach improves student academic outcomes and represents a valuable method to incorporate active learning methodologies while still maintaining broad content coverage. Satisfaction with this approach was high, and we are currently developing more pharmacy content for delivery in this format.

Keywords: active learning, blended learning, deep conceptual learning, instructional approach, metacognition, pharmaceutical calculations

Procedia PDF Downloads 155
782 Eco-Politics of Infrastructure Development in and Around Protected Areas in Kenya: The Case of Nairobi National Park

Authors: Teresa Wanjiru Mbatia

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On 7th June 2011, the government Minister of Roads in Kenya announced the proposed construction of a major highway known as a southern bypass to run on the northern border of the Nairobi National Park. The following day on 8th June 2011, the chairperson of the Friends of Nairobi National Park (FONNAP) posted a protest statement on their website, with the heading, ‘Nairobi Park is Not a cake’ alerting its members and conservation groups, with the aim of getting support to the campaign against the government’s intention to hive off a section of the park for road construction. This was the first and earliest statement that led to a series of other events that culminated in conservationists and some other members of the public campaign against the government’s plan to hive off sections of the park to build road and railway infrastructure in or around the park. Together with other non-state actors, mostly non-governmental organisations in conservation/environment and tourism businesses, FoNNAP issued a series of other statements on social, print and electronic media to battle against road and railway construction. This paper examined the strategies, outcomes and interests of actors involved in opposing/proposing the development of transport infrastructure in and around the Nairobi National Park. Specifically, the objectives were to analyse the: (1) Arguments put forward by the eco-warriors to protest infrastructure development; (2) Background and interests of the eco-warriors; (3) Needs/interests and opinions of ordinary common citizens on transport infrastructural development, particularly in and around the urban nature reserve and (4) Final outcomes of the eco-politics surrounding infrastructure development in and around Nairobi National Park. The methodological approach used was environmental history and the social construction of nature. The study collected combined qualitative data using four main approaches, the grounded theory approach, narratives, case studies and a phenomenological approach. The information collected was analysed using critical discourse analysis. The major findings of the study were that under the guise of “public participation,” influential non-state actors have the capacity to perpetuate social-spatial inequalities in the form of curtailing the majority from accessing common public goods. A case in point in this study is how the efforts of powerful conservationists, environmentalists, and tourism businesspersons managed to stall the construction of much-needed road and railway infrastructure severally through litigations in lengthy environmental court processes involving injunctions and stop orders to the government bodies in charge. Moreover, powerful non-state actors were found to have formed informal and sometimes formal coalitions with politicians with selfish interests, which serves to deepen the exclusionary practices and the common good. The study concludes that mostly composed of certain types of elites (NGOs, business communities, politicians and privileged social-cultural groups), non-state actors have used participatory policies to advance their own interests at the expense of the majority whom they claim to represent. These practices are traced to the historically unjust social, political, and economic forces involved in the production of space in Nairobi.

Keywords: eco-politics, exclusion, infrastructure, Nairobi national park, non-state actors, protests

Procedia PDF Downloads 159
781 Hydrogen Induced Fatigue Crack Growth in Pipeline Steel API 5L X65: A Combined Experimental and Modelling Approach

Authors: H. M. Ferreira, H. Cockings, D. F. Gordon

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Climate change is driving a transition in the energy sector, with low-carbon energy sources such as hydrogen (H2) emerging as an alternative to fossil fuels. However, the successful implementation of a hydrogen economy requires an expansion of hydrogen production, transportation and storage capacity. The costs associated with this transition are high but can be partly mitigated by adapting the current oil and natural gas networks, such as pipeline, an important component of the hydrogen infrastructure, to transport pure or blended hydrogen. Steel pipelines are designed to withstand fatigue, one of the most common causes of pipeline failure. However, it is well established that some materials, such as steel, can fail prematurely in service when exposed to hydrogen-rich environments. Therefore, it is imperative to evaluate how defects (e.g. inclusions, dents, and pre-existing cracks) will interact with hydrogen under cyclic loading and, ultimately, to what extent hydrogen induced failure will limit the service conditions of steel pipelines. This presentation will explore how the exposure of API 5L X65 to a hydrogen-rich environment and cyclic loads will influence its susceptibility to hydrogen induced failure. That evaluation will be performed by a combination of several techniques such as hydrogen permeation testing (ISO 17081:2014), fatigue crack growth (FCG) testing (ISO 12108:2018 and AFGROW modelling), combined with microstructural and fractographic analysis. The development of a FCG test setup coupled with an electrochemical cell will be discussed, along with the advantages and challenges of measuring crack growth rates in electrolytic hydrogen environments. A detailed assessment of several electrolytic charging conditions will also be presented, using hydrogen permeation testing as a method to correlate the different charging settings to equivalent hydrogen concentrations and effective diffusivity coefficients, not only on the base material but also on the heat affected zone and weld of the pipelines. The experimental work is being complemented with AFGROW, a useful FCG modelling software that has helped inform testing parameters and which will also be developed to ultimately help industry experts perform structural integrity analysis and remnant life characterisation of pipeline steels under representative conditions. The results from this research will allow to conclude if there is an acceleration of the crack growth rate of API 5L X65 under the influence of a hydrogen-rich environment, an important aspect that needs to be rectified instandards and codes of practice on pipeline integrity evaluation and maintenance.

Keywords: AFGROW, electrolytic hydrogen charging, fatigue crack growth, hydrogen, pipeline, steel

Procedia PDF Downloads 85
780 Rapid Soil Classification Using Computer Vision with Electrical Resistivity and Soil Strength

Authors: Eugene Y. J. Aw, J. W. Koh, S. H. Chew, K. E. Chua, P. L. Goh, Grace H. B. Foo, M. L. Leong

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This paper presents the evaluation of various soil testing methods such as the four-probe soil electrical resistivity method and cone penetration test (CPT) that can complement a newly developed novel rapid soil classification scheme using computer vision, to improve the accuracy and productivity of on-site classification of excavated soil. In Singapore, excavated soils from the local construction industry are transported to Staging Grounds (SGs) to be reused as fill material for land reclamation. Excavated soils are mainly categorized into two groups (“Good Earth” and “Soft Clay”) based on particle size distribution (PSD) and water content (w) from soil investigation reports and on-site visual survey, such that proper treatment and usage can be exercised. However, this process is time-consuming and labor-intensive. Thus, a rapid classification method is needed at the SGs. Four-probe soil electrical resistivity and CPT were evaluated for their feasibility as suitable additions to the computer vision system to further develop this innovative non-destructive and instantaneous classification method. The computer vision technique comprises soil image acquisition using an industrial-grade camera; image processing and analysis via calculation of Grey Level Co-occurrence Matrix (GLCM) textural parameters; and decision-making using an Artificial Neural Network (ANN). It was found from the previous study that the ANN model coupled with ρ can classify soils into “Good Earth” and “Soft Clay” in less than a minute, with an accuracy of 85% based on selected representative soil images. To further improve the technique, the following three items were targeted to be added onto the computer vision scheme: the apparent electrical resistivity of soil (ρ) measured using a set of four probes arranged in Wenner’s array, the soil strength measured using a modified mini cone penetrometer, and w measured using a set of time-domain reflectometry (TDR) probes. Laboratory proof-of-concept was conducted through a series of seven tests with three types of soils – “Good Earth”, “Soft Clay,” and a mix of the two. Validation was performed against the PSD and w of each soil type obtained from conventional laboratory tests. The results show that ρ, w and CPT measurements can be collectively analyzed to classify soils into “Good Earth” or “Soft Clay” and are feasible as complementing methods to the computer vision system.

Keywords: computer vision technique, cone penetration test, electrical resistivity, rapid and non-destructive, soil classification

Procedia PDF Downloads 218
779 Rethinking Urban Voids: An Investigation beneath the Kathipara Flyover, Chennai into a Transit Hub by Adaptive Utilization of Space

Authors: V. Jayanthi

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Urbanization and pace of urbanization have increased tremendously in last few decades. More towns are now getting converted into cities. Urbanization trend is seen all over the world but is becoming most dominant in Asia. Today, the scale of urbanization in India is so huge that Indian cities are among the fastest-growing in the world, including Bangalore, Hyderabad, Pune, Chennai, Delhi, and Mumbai. Urbanization remains a single predominant factor that is continuously linked to the destruction of urban green spaces. With reference to Chennai as a case study, which is suffering from rapid deterioration of its green spaces, this paper sought to fill this gap by exploring key factors aside urbanization that is responsible for the destruction of green spaces. The paper relied on a research approach and triangulated data collection techniques such as interviews, focus group discussion, personal observation and retrieval of archival data. It was observed that apart from urbanization, problem of ownership of green space lands, low priority to green spaces, poor maintenance, enforcement of development controls, wastage of underpass spaces, and uncooperative attitudes of the general public, play a critical role in the destruction of urban green spaces. Therefore the paper narrows down to a point, that for a city to have a proper sustainable urban green space, broader city development plans are essential. Though rapid urbanization is an indicator of positive development, it is also accompanied by a host of challenges. Chennai lost a lot of greenery, as the city urbanized rapidly that led to a steep fall in vegetation cover. Environmental deterioration will be the big price we pay if Chennai continues to grow at the expense of greenery. Soaring skyscrapers, multistoried complexes, gated communities, and villas, frame the iconic skyline of today’s Chennai city which reveals that we overlook the importance of our green cover, which is important to balance our urban and lung spaces. Chennai, with a clumped landscape at the center of the city, is predicted to convert 36% of its total area into urban areas by 2026. One major issue is that a city designed and planned in isolation creates underused spaces all around the cities which are of negligence. These urban voids are dead, underused, unused spaces in the cities that are formed due to inefficient decision making, poor land management, and poor coordination. Urban voids have huge potential of creating a stronger urban fabric, exploited as public gathering spaces, pocket parks or plazas or just enhance public realm, rather than dumping of debris and encroachments. Flyovers need to justify their existence themselves by being more than just traffic and transport solutions. The vast, unused space below the Kathipara flyover is a case in point. This flyover connects three major routes: Tambaram, Koyambedu, and Adyar. This research will focus on the concept of urban voids, how these voids under the flyovers, can be used for place making process, how this space beneath flyovers which are neglected, can be a part of the urban realm through urban design and landscaping.

Keywords: landscape design, flyovers, public spaces, reclaiming lost spaces, urban voids

Procedia PDF Downloads 240
778 3D Printing of Polycaprolactone Scaffold with Multiscale Porosity Via Incorporation of Sacrificial Sucrose Particles

Authors: Mikaela Kutrolli, Noah S. Pereira, Vanessa Scanlon, Mohamadmahdi Samandari, Ali Tamayol

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Bone tissue engineering has drawn significant attention and various biomaterials have been tested. Polymers such as polycaprolactone (PCL) offer excellent biocompatibility, reasonable mechanical properties, and biodegradability. However, PCL scaffolds suffer a critical drawback: a lack of micro/mesoporosity, affecting cell attachment, tissue integration, and mineralization. It also results in a slow degradation rate. While 3D-printing has addressed the issue of macroporosity through CAD-guided fabrication, PCL scaffolds still exhibit poor smaller-scale porosity. To overcome this, we generated composites of PCL, hydroxyapatite (HA), and powdered sucrose (PS). The latter serves as a sacrificial material to generate porous particles after sucrose dissolution. Additionally, we have incorporated dexamethasone (DEX) to boost the PCL osteogenic properties. The resulting scaffolds maintain controlled macroporosity from the lattice print structure but also develop micro/mesoporosity within PCL fibers when exposed to aqueous environments. The study involved mixing PS into solvent-dissolved PCL in different weight ratios of PS to PCL (70:30, 50:50, and 30:70 wt%). The resulting composite was used for 3D printing of scaffolds at room temperature. Printability was optimized by adjusting pressure, speed, and layer height through filament collapse and fusion test. Enzymatic degradation, porogen leaching, and DEX release profiles were characterized. Physical properties were assessed using wettability, SEM, and micro-CT to quantify the porosity (percentage, pore size, and interconnectivity). Raman spectroscopy was used to verify the absence of sugar after leaching. Mechanical characteristics were evaluated via compression testing before and after porogen leaching. Bone marrow stromal cells (BMSCs) behavior in the printed scaffolds was studied by assessing viability, metabolic activity, osteo-differentiation, and mineralization. The scaffolds with a 70% sugar concentration exhibited superior printability and reached the highest porosity of 80%, but performed poorly during mechanical testing. A 50% PS concentration demonstrated a 70% porosity, with an average pore size of 25 µm, favoring cell attachment. No trace of sucrose was found in Raman after leaching the sugar for 8 hours. Water contact angle results show improved hydrophilicity as the sugar concentration increased, making the scaffolds more conductive to cell adhesion. The behavior of bone marrow stromal cells (BMSCs) showed positive viability and proliferation results with an increasing trend of mineralization and osteo-differentiation as the sucrose concentration increased. The addition of HA and DEX also promoted mineralization and osteo-differentiation in the cultures. The integration of PS as porogen at a concentration of 50%wt within PCL scaffolds presents a promising approach to address the poor cell attachment and tissue integration issues of PCL in bone tissue engineering. The method allows for the fabrication of scaffolds with tunable porosity and mechanical properties, suitable for various applications. The addition of HA and DEX further enhanced the scaffolds. Future studies will apply the scaffolds in an in-vivo model to thoroughly investigate their performance.

Keywords: bone, PCL, 3D printing, tissue engineering

Procedia PDF Downloads 34
777 Quantification and Detection of Non-Sewer Water Infiltration and Inflow in Urban Sewer Systems

Authors: M. Beheshti, S. Saegrov, T. M. Muthanna

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Separated sewer systems are designed to transfer the wastewater from houses and industrial sections to wastewater treatment plants. Unwanted water in the sewer systems is a well-known problem, i.e. storm-water inflow is around 50% of the foul sewer, and groundwater infiltration to the sewer system can exceed 50% of total wastewater volume in deteriorated networks. Infiltration and inflow of non-sewer water (I/I) into sewer systems is unfavorable in separated sewer systems and can trigger overloading the system and reducing the efficiency of wastewater treatment plants. Moreover, I/I has negative economic, environmental, and social impacts on urban areas. Therefore, for having sustainable management of urban sewer systems, I/I of unwanted water into the urban sewer systems should be considered carefully and maintenance and rehabilitation plan should be implemented on these water infrastructural assets. This study presents a methodology to identify and quantify the level of I/I into the sewer system. Amount of I/I is evaluated by accurate flow measurement in separated sewer systems for specified isolated catchments in Trondheim city (Norway). Advanced information about the characteristics of I/I is gained by CCTV inspection of sewer pipelines with high I/I contribution. Achieving enhanced knowledge about the detection and localization of non-sewer water in foul sewer system during the wet and dry weather conditions will enable the possibility for finding the problem of sewer system and prioritizing them and taking decisions for rehabilitation and renewal planning in the long-term. Furthermore, preventive measures and optimization of sewer systems functionality and efficiency can be executed by maintenance of sewer system. In this way, the exploitation of sewer system can be improved by maintenance and rehabilitation of existing pipelines in a sustainable way by more practical cost-effective and environmental friendly way. This study is conducted on specified catchments with different properties in Trondheim city. Risvollan catchment is one of these catchments with a measuring station to investigate hydrological parameters through the year, which also has a good database. For assessing the infiltration in a separated sewer system, applying the flow rate measurement method can be utilized in obtaining a general view of the network condition from infiltration point of view. This study discusses commonly used and advanced methods of localizing and quantifying I/I in sewer systems. A combination of these methods give sewer operators the possibility to compare different techniques and obtain reliable and accurate I/I data which is vital for long-term rehabilitation plans.

Keywords: flow rate measurement, infiltration and inflow (I/I), non-sewer water, separated sewer systems, sustainable management

Procedia PDF Downloads 305
776 Flood Early Warning and Management System

Authors: Yogesh Kumar Singh, T. S. Murugesh Prabhu, Upasana Dutta, Girishchandra Yendargaye, Rahul Yadav, Rohini Gopinath Kale, Binay Kumar, Manoj Khare

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The Indian subcontinent is severely affected by floods that cause intense irreversible devastation to crops and livelihoods. With increased incidences of floods and their related catastrophes, an Early Warning System for Flood Prediction and an efficient Flood Management System for the river basins of India is a must. Accurately modeled hydrological conditions and a web-based early warning system may significantly reduce economic losses incurred due to floods and enable end users to issue advisories with better lead time. This study describes the design and development of an EWS-FP using advanced computational tools/methods, viz. High-Performance Computing (HPC), Remote Sensing, GIS technologies, and open-source tools for the Mahanadi River Basin of India. The flood prediction is based on a robust 2D hydrodynamic model, which solves shallow water equations using the finite volume method. Considering the complexity of the hydrological modeling and the size of the basins in India, it is always a tug of war between better forecast lead time and optimal resolution at which the simulations are to be run. High-performance computing technology provides a good computational means to overcome this issue for the construction of national-level or basin-level flash flood warning systems having a high resolution at local-level warning analysis with a better lead time. High-performance computers with capacities at the order of teraflops and petaflops prove useful while running simulations on such big areas at optimum resolutions. In this study, a free and open-source, HPC-based 2-D hydrodynamic model, with the capability to simulate rainfall run-off, river routing, and tidal forcing, is used. The model was tested for a part of the Mahanadi River Basin (Mahanadi Delta) with actual and predicted discharge, rainfall, and tide data. The simulation time was reduced from 8 hrs to 3 hrs by increasing CPU nodes from 45 to 135, which shows good scalability and performance enhancement. The simulated flood inundation spread and stage were compared with SAR data and CWC Observed Gauge data, respectively. The system shows good accuracy and better lead time suitable for flood forecasting in near-real-time. To disseminate warning to the end user, a network-enabled solution is developed using open-source software. The system has query-based flood damage assessment modules with outputs in the form of spatial maps and statistical databases. System effectively facilitates the management of post-disaster activities caused due to floods, like displaying spatial maps of the area affected, inundated roads, etc., and maintains a steady flow of information at all levels with different access rights depending upon the criticality of the information. It is designed to facilitate users in managing information related to flooding during critical flood seasons and analyzing the extent of the damage.

Keywords: flood, modeling, HPC, FOSS

Procedia PDF Downloads 75
775 Building User Behavioral Models by Processing Web Logs and Clustering Mechanisms

Authors: Madhuka G. P. D. Udantha, Gihan V. Dias, Surangika Ranathunga

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Today Websites contain very interesting applications. But there are only few methodologies to analyze User navigations through the Websites and formulating if the Website is put to correct use. The web logs are only used if some major attack or malfunctioning occurs. Web Logs contain lot interesting dealings on users in the system. Analyzing web logs has become a challenge due to the huge log volume. Finding interesting patterns is not as easy as it is due to size, distribution and importance of minor details of each log. Web logs contain very important data of user and site which are not been put to good use. Retrieving interesting information from logs gives an idea of what the users need, group users according to their various needs and improve site to build an effective and efficient site. The model we built is able to detect attacks or malfunctioning of the system and anomaly detection. Logs will be more complex as volume of traffic and the size and complexity of web site grows. Unsupervised techniques are used in this solution which is fully automated. Expert knowledge is only used in validation. In our approach first clean and purify the logs to bring them to a common platform with a standard format and structure. After cleaning module web session builder is executed. It outputs two files, Web Sessions file and Indexed URLs file. The Indexed URLs file contains the list of URLs accessed and their indices. Web Sessions file lists down the indices of each web session. Then DBSCAN and EM Algorithms are used iteratively and recursively to get the best clustering results of the web sessions. Using homogeneity, completeness, V-measure, intra and inter cluster distance and silhouette coefficient as parameters these algorithms self-evaluate themselves to input better parametric values to run the algorithms. If a cluster is found to be too large then micro-clustering is used. Using Cluster Signature Module the clusters are annotated with a unique signature called finger-print. In this module each cluster is fed to Associative Rule Learning Module. If it outputs confidence and support as value 1 for an access sequence it would be a potential signature for the cluster. Then the access sequence occurrences are checked in other clusters. If it is found to be unique for the cluster considered then the cluster is annotated with the signature. These signatures are used in anomaly detection, prevent cyber attacks, real-time dashboards that visualize users, accessing web pages, predict actions of users and various other applications in Finance, University Websites, News and Media Websites etc.

Keywords: anomaly detection, clustering, pattern recognition, web sessions

Procedia PDF Downloads 272
774 Velma-ARC’s Rehabilitation of Repentant Cybercriminals in Nigeria

Authors: Umukoro Omonigho Simon, Ashaolu David ‘Diya, Aroyewun-Olaleye Temitope Folashade

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The VELMA Action to Reduce Cybercrime (ARC) is an initiative, the first of its kind in Nigeria, designed to identify, rehabilitate and empower repentant cybercrime offenders popularly known as ‘yahoo boys’ in Nigerian parlance. Velma ARC provides social inclusion boot camps with the goal of rehabilitating cybercriminals via psychotherapeutic interventions, improving their IT skills, and empowering them to make constructive contributions to society. This report highlights the psychological interventions provided for participants of the maiden edition of the Velma ARC boot camp and presents the outcomes of these interventions. The boot camp was set up in a hotel premises which was booked solely for the 1 month event. The participants were selected and invited via the Velma online recruitment portal based on an objective double-blind selection process from a pool of potential participants who signified interest via the registration portal. The participants were first taken through psychological profiling (personality, symptomology and psychopathology) before the individual and group sessions began. They were profiled using the Minnesota Multiphasic Personality Inventory -2- Restructured Form (MMPI-2-RF), the latest version of its series. Individual psychotherapy sessions were conducted for all participants based on what was interpreted on their profiles. Focus group discussion was held later to discuss a movie titled ‘catch me if you can’ directed by Steven Spielberg, featuring Leonardo De Caprio and Tom Hanks. The movie was based on the true life story of Frank Abagnale, who was a notorious scammer and con artist in his youthful years. Emergent themes from the movie were discussed as psycho-educative parameters for the participants. The overall evaluation of outcomes from the VELMA ARC rehabilitation boot camp stemmed from a disaggregated assessment of observed changes which are summarized in the final report of the clinical psychologist and was detailed enough to infer genuine repentance and positive change in attitude towards cybercrime among the participants. Follow up services were incorporated to validate initial observations. This gives credence to the potency of the psycho-educative intervention provided during the Velma ARC boot camp. It was recommended that support and collaborations from the government and other agencies/individuals would assist the VELMA foundation in expanding the scope and quality of the Velma ARC initiative as an additional requirement for cybercrime offenders following incarceration.

Keywords: Velma-ARC, cybercrime offenders, rehabilitation, Nigeria

Procedia PDF Downloads 132
773 Metagenomic Assessment of the Effects of Genetically Modified Crops on Microbial Ecology and Physicochemical Properties of Soil

Authors: Falana Yetunde Olaitan, Ijah U. J. J, Solebo Shakirat O.

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Genetically modified crops are already phenomenally successful and are grown worldwide in more than eighteen countries on more than 67 million hectares. Nigeria, in October 2018, approved Bacillus thuringiensis (Bt) cotton and maize; therefore, the need to carry out environmental risk assessment studies. A total of 15 4L octagonal ceramic pots were filled with 4kg of soil and placed on the bench in 2 rows of 10 pots each and the 3rd row of 5 pots, 1st-row pots were used to plant GM cotton seeds, while the 2nd-row pots were used for non-GM cotton seeds and the 3rd row of 5 pots served as control, all in the screen house. Soil samples for metagenomic DNA extraction were collected at random and at the monthly interval after planting at a distance of 2mm from the plant’s root and at a depth of 10cm using a sterile spatula. Soil samples for physicochemical analysis were collected before planting and after harvesting the GM and non-GM crops as well as from the control soil. The DNA was extracted, quantified and sequenced; Sample 1A (DNA from GM cotton Soil at 1st interval) gave the lowest sequence read with 0.853M while sample 2B (DNA from GM cotton Soil at 2nd interval) gave the highest with 5.785M, others gave between 1.8M and 4.7M. The samples treatment were grouped into four, Group 1 (GM cotton soil from 1 to 3 intervals) had between 800,000 and 5,700,000 strains of microbes (SOM), Group 2 (non GM cotton soil from 1 to 3 intervals) had between 1,400,600 and 4,200,000 SOM, Group 3 (control soil) had between 900,000 and 3,600,000 SOM and Group 4 (initial soil) had between 3,700,000 and 4,000,000 SOM. The microbes observed were predominantly bacteria (including archaea), fungi, dark matter alongside protists and phages. The predominant bacterial groups were the Terrabacteria (Bacillus funiculus, Bacillus sp.), the Proteobacteria (Microvirga massiliensis, sphingomonas sp.) and the Archaea (Nitrososphaera sp.), while the fungi were Aspergillus fischeri and Fusarium falciforme. The comparative analysis between groups was done using JACCARD PERMANOVA beta diversity analysis at P-value not more than 0.76 and there was no significant pair found. The pH for initial, GM cotton, non-GM cotton and control soil were 6.28, 6.26, 7.25, 8.26 and the percentage moisture was 0.63, 0.78, 0.89 and 0.82, respectively, while the percentage Nitrogen was observed to be 17.79, 1.14, 1.10 and 0.56 respectively. Other parameters include, varying concentrations of Potassium (0.46, 1,284.47, 1,785.48, 1,252.83 mg/kg) and Phosphorus (18.76, 17.76, 16.87, 15.23 mg/kg) were recorded for the four treatments respectively. The soil consisted mainly of silt (32.09 to 34.66%) and clay (58.89 to 60.23%), reflecting the soil texture as silty – clay. The results were then tested with ANOVA at less than 0.05 P-value and no pair was found to be significant as well. The results suggest that the GM crops have no significant effect on microbial ecology and physicochemical properties of the soil and, in turn, no direct or indirect effects on human health.

Keywords: genetically modified crop, microbial ecology, physicochemical properties, metagenomics, DNA, soil

Procedia PDF Downloads 130
772 Calcium Release- Activated Calcium Channels as a Target in Treatment of Allergic Asthma

Authors: Martina Šutovská, Marta Jošková, Ivana Kazimierová, Lenka Pappová, Maroš Adamkov, Soňa Fraňová

Abstract:

Bronchial asthma is characterized by increased bronchoconstrictor responses to provoking agonists, airway inflammation and remodeling. All these processes involve Ca2+ influx through Ca2+-release-activated Ca2+ channels (CRAC) that are widely expressed in immune, respiratory epithelium and airway smooth muscle (ASM) cells. Our previous study pointed on possible therapeutic potency of CRAC blockers using experimental guinea pigs asthma model. Presented work analyzed complex anti-asthmatic effect of long-term administered CRAC blocker, including impact on allergic inflammation, airways hyperreactivity, and remodeling and mucociliary clearance. Ovalbumin-induced allergic inflammation of the airways according to Franova et al. was followed by 14 days lasted administration of CRAC blocker (3-fluoropyridine-4-carboxylic acid, FPCA) in the dose 1.5 mg/kg bw. For comparative purposes salbutamol, budesonide and saline were applied to control groups. The anti-inflammatory effect of FPCA was estimated by serum and bronchoalveolar lavage fluid (BALF) changes in IL-4, IL-5, IL-13 and TNF-α analyzed by Bio-Plex® assay as well as immunohistochemical staining focused on assessment of tryptase and c-Fos positivity in pulmonary samples. The in vivo airway hyperreactivity was evaluated by Pennock et al. and by organ tissue bath methods in vitro. The immunohistochemical changes in ASM actin and collagen III layer as well as mucin secretion evaluated anti-remodeling effect of FPCA. The measurement of ciliary beat frequency (CBF) in vitro using LabVIEW™ Software determined impact on mucociliary clearance. Long-term administration of FPCA to sensitized animals resulted in: i. Significant decrease in cytokine levels, tryptase and c-Fos positivity similar to budesonide effect; ii.Meaningful decrease in basal and bronchoconstrictors-induced in vivo and in vitro airway hyperreactivity comparable to salbutamol; iii. Significant inhibition of airway remodeling parameters; iv. Insignificant changes in CBF. All these findings confirmed complex anti-asthmatic effect of CRAC channels blocker and evidenced these structures as the rational target in the treatment of allergic bronchial asthma.

Keywords: allergic asthma, CRAC channels, cytokines, respiratory epithelium

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771 Pareto Optimal Material Allocation Mechanism

Authors: Peter Egri, Tamas Kis

Abstract:

Scheduling problems have been studied by the algorithmic mechanism design research from the beginning. This paper is focusing on a practically important, but theoretically rather neglected field: the project scheduling problem where the jobs connected by precedence constraints compete for various nonrenewable resources, such as materials. Although the centralized problem can be solved in polynomial-time by applying the algorithm of Carlier and Rinnooy Kan from the Eighties, obtaining materials in a decentralized environment is usually far from optimal. It can be observed in practical production scheduling situations that project managers tend to cache the required materials as soon as possible in order to avoid later delays due to material shortages. This greedy practice usually leads both to excess stocks for some projects and materials, and simultaneously, to shortages for others. The aim of this study is to develop a model for the material allocation problem of a production plant, where a central decision maker—the inventory—should assign the resources arriving at different points in time to the jobs. Since the actual due dates are not known by the inventory, the mechanism design approach is applied with the projects as the self-interested agents. The goal of the mechanism is to elicit the required information and allocate the available materials such that it minimizes the maximal tardiness among the projects. It is assumed that except the due dates, the inventory is familiar with every other parameters of the problem. A further requirement is that due to practical considerations monetary transfer is not allowed. Therefore a mechanism without money is sought which excludes some widely applied solutions such as the Vickrey–Clarke–Groves scheme. In this work, a type of Serial Dictatorship Mechanism (SDM) is presented for the studied problem, including a polynomial-time algorithm for computing the material allocation. The resulted mechanism is both truthful and Pareto optimal. Thus the randomization over the possible priority orderings of the projects results in a universally truthful and Pareto optimal randomized mechanism. However, it is shown that in contrast to problems like the many-to-many matching market, not every Pareto optimal solution can be generated with an SDM. In addition, no performance guarantee can be given compared to the optimal solution, therefore this approximation characteristic is investigated with experimental study. All in all, the current work studies a practically relevant scheduling problem and presents a novel truthful material allocation mechanism which eliminates the potential benefit of the greedy behavior that negatively influences the outcome. The resulted allocation is also shown to be Pareto optimal, which is the most widely used criteria describing a necessary condition for a reasonable solution.

Keywords: material allocation, mechanism without money, polynomial-time mechanism, project scheduling

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770 Systematic Review of Technology-Based Mental Health Solutions for Modelling in Low and Middle Income Countries

Authors: Mukondi Esther Nethavhakone

Abstract:

In 2020 World Health Organization announced the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), also known as Coronavirus disease 2019 (COVID-19) pandemic. To curb or contain the spread of the novel coronavirus (COVID 19), global governments implemented social distancing and lockdown regulations. Subsequently, it was no longer business as per usual, life as we knew it had changed, and so many aspects of people's lives were negatively affected, including financial and employment stability. Mainly, because companies/businesses had to put their operations on hold, some had to shut down completely, resulting in the loss of income for many people globally. Finances and employment insecurities are some of the issues that exacerbated many social issues that the world was already faced with, such as school drop-outs, teenage pregnancies, sexual assaults, gender-based violence, crime, child abuse, elderly abuse, to name a few. Expectedly the majority of the population's mental health state was threatened. This resulted in an increased number of people seeking mental healthcare services. The increasing need for mental healthcare services in Low and Middle-income countries proves to be a challenge because it is a well-known fact due to financial constraints and not well-established healthcare systems, mental healthcare provision is not as prioritised as the primary healthcare in these countries. It is against this backdrop that the researcher seeks to find viable, cost-effective, and accessible mental health solutions for low and middle-income countries amid the pressures of any pandemic. The researcher will undertake a systematic review of the technology-based mental health solutions that have been implemented/adopted by developed countries during COVID 19 lockdown and social distancing periods. This systematic review study aims to determine if low and middle-income countries can adopt the cost-effective version of digital mental health solutions for the healthcare system to adequately provide mental healthcare services during critical times such as pandemics (when there's an overwhelming diminish in mental health globally). The researcher will undertake a systematic review study through mixed methods. It will adhere to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The mixed-methods uses findings from both qualitative and quantitative studies in one review study. It will be beneficial to conduct this kind of study using mixed methods because it is a public health topic that involves social interventions and it is not purely based on medical interventions. Therefore, the meta-ethnographic (qualitative data) analysis will be crucial in understanding why and which digital methods work and for whom does it work, rather than only the meta-analysis (quantitative data) providing what digital mental health methods works. The data collection process will be extensive, involving the development of a database, table of summary of evidence/findings, and quality assessment process lastly, The researcher will ensure that ethical procedures are followed and adhered to, ensuring that sensitive data is protected and the study doesn't pose any harm to the participants.

Keywords: digital, mental health, covid, low and middle-income countries

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769 Reviving the Past, Enhancing the Future: Preservation of Urban Heritage Connectivity as a Tool for Developing Liveability in Historical Cities in Jordan, Using as Salt City as a Case Study

Authors: Sahar Yousef, Chantelle Niblock, Gul Kacmaz

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Salt City, in the context of Jordan’s heritage landscape, is a significant case to explore when it comes to the interaction between tangible and intangible qualities of liveable cities. Most city centers, including Jerash, Salt, Irbid, and Amman, are historical locations. Six of these extraordinary sites were designated UNESCO World Heritage Sites. Jordan is widely acknowledged as a developing country characterized by swift urbanization and unrestrained expansion that exacerbate the challenges associated with the preservation of historic urban areas. The aim of this study is to conduct an examination and analysis of the existing condition of heritage connectivity within heritage city centers. This includes outdoor staircases, pedestrian pathways, footpaths, and other public spaces. Case study-style analysis of the urban core of As-Salt is the focus of this investigation. Salt City is widely acknowledged for its substantial tangible and intangible cultural heritage and has been designated as ‘The Place of Tolerance and Urban Hospitality’ by UNESCO since 2021. Liveability in urban heritage, particularly in historic city centers, incorporates several factors that affect our well-being; its enhancement is a critical issue in contemporary society. The dynamic interaction between humans and historical materials, which serves as a vehicle for the expression of their identity and historical narrative, constitutes preservation that transcends simple conservation. This form of engagement enables people to appreciate the diversity of their heritage recognising their previous and planned futures. Heritage preservation is inextricably linked to a larger physical and emotional context; therefore, it is difficult to examine it in isolation. Urban environments, including roads, structures, and other infrastructure, are undergoing unprecedented physical design and construction requirements. Concurrently, heritage reinforces a sense of affiliation with a particular location or space and unifies individuals with their ancestry, thereby defining their identity. However, a considerable body of research has focused on the conservation of heritage buildings in a fragmented manner without considering their integration within a holistic urban context. Insufficient attention is given to the significance of the physical and social roles played by the heritage staircases and baths that serve as connectors between these valued historical buildings. In doing so, the research uses a methodology that is based on consensus. Given that liveability is considered a complex matter with several dimensions. The discussion starts by making initial observations on the physical context and societal norms inside the urban center while simultaneously establishing the definitions of liveability and connectivity and examining the key criteria associated with these concepts. Then, identify the key elements that contribute to liveable connectivity within the framework of urban heritage in Jordanian city centers. Some of the outcomes that will be discussed in the presentation are: (1) There is not enough connectivity between heritage buildings as can be seen, for example, between buildings in Jada and Qala'. (2) Most of the outdoor spaces suffer from physical issues that hinder their use by the public, like in Salalem. (3) Existing activities in the city center are not well attended because of lack of communication between the organisers and the citizens.

Keywords: connectivity, Jordan, liveability, salt city, tangible and intangible heritage, urban heritage

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768 Early Help Family Group Conferences: An Analysis of Family Plans

Authors: Kate Parkinson

Abstract:

A Family Group Conference (FGC) is a family-led decision-making process through which a family/kinship group, rather than the professionals involved, is asked to develop a plan for the care or the protection of children in the family. In England and Wales, FGCs are used in 76% of local authorities and in recent years, have tended to be used in cases where the local authority are considering the court process to remove children from their immediate family, to explore kinship alternatives to local authority care. Some local authorities offer the service much earlier, when families first come to the attention of children's social care, in line with research that suggests the earlier an FGC is held, the more likely they are to be successful. Family plans that result from FGCs are different from professional plans in that they are unique to a family and, as a result, reflect the diversity of families. Despite the fact that FGCs are arguable the most researched area of social work globally, there is a dearth of research that examines the nature of family plans and their substance. This paper presents the findings of a documentary analysis of 42 Early Help FGC plans from local authorities in England, with the aim of exploring the level and type of support that family members offer at a FGC. A thematic analysis identified 5 broad areas of support: Practical Support, Building Relationships, Child-care Support, Emotional Support and Social Support. In the majority of cases, family members did not want or ask for any formal support from the local authority or other agencies. Rather, the families came together to agree a plan of support, which was within the parameters of the resources that they as a family could provide. Perhaps then the role of the Early Help professional should be one of a facilitating and enabling role, to support families to develop plans that address their own specific difficulties, rather than the current default option, which is to either close the case because the family do not meet service thresholds or refer to formal support if they do, which may offer very specific support, have rigid referral criteria, long waiting lists and may not reflect the diverse and unique nature of families. FGCs are argued to be culturally appropriate social work practices in that they are appropriate for families from a range of cultural backgrounds and can be adapted to meet particular cultural needs. Furthermore, research on the efficacy of FGCs at an Early Help Level has demonstrated that Early Help FGCs have the potential to address difficulties in family life and prevent the need for formal support services, which are potentially stigmatising and do not reflect the uniqueness and diversity of families. The paper concludes with a recommendation for the use of FGCs across Early Help Services in England and Wales.

Keywords: family group conferences, family led decision making, early help, prevention

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767 Effect of Different Parameters of Converging-Diverging Vortex Finders on Cyclone Separator Performance

Authors: V. Kumar, K. Jha

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The present study is done to explore design modifications of the vortex finder, as it has a significant effect on the cyclone separator performance. It is evident that modifications of the vortex finder improve the performance of the cyclone separator significantly. The study conducted strives to improve the overall performance of cyclone separators by utilizing a converging-diverging (CD) vortex finder instead of the traditional uniform diameter vortex finders. The velocity and pressure fields inside a Stairmand cyclone separator with body diameter 0.29m and vortex finder diameter 0.1305m are calculated. The commercial software, Ansys Fluent v14.0 is used to simulate the flow field in a uniform diameter cyclone and six cyclones modified with CD vortex finders. Reynolds stress model is used to simulate the effects of turbulence on the fluid and particulate phases, discrete phase model is used to calculate the particle trajectories. The performance of the modified vortex finders is compared with the traditional vortex finder. The effects of the lengths of the converging and diverging sections, the throat diameter and the end diameters of the convergent divergent section are also studied to achieve enhanced performance. The pressure and velocity fields inside the vortex finder are presented by means of contour plots and velocity vectors and changes in the flow pattern due to variation of the geometrical variables are also analysed. Results indicate that a convergent-divergent vortex finder is capable of decreasing the pressure drop than that achieved through a uniform diameter vortex finder. It is also observed that the end diameters of the CD vortex finder, the throat diameter and the length of the diverging part of the vortex finder have a significant impact on the cyclone separator performance. Increase in the lower diameter of the vortex finder by 66% results in 11.5% decrease in the dimensionless pressure drop (Euler number) with 5.8% decrease in separation efficiency. Whereas 50% decrease in the throat diameter gives 5.9% increase in the Euler number with 10.2% increase in the separation efficiency and increasing the length of the diverging part gives 10.28% increase in the Euler number with 5.74% increase in the separation efficiency. Increasing the upper diameter of the CD vortex finder is seen to produce an adverse effect on the performance as it increases the pressure drop significantly and decreases the separation efficiency. Increase in length of the converging is not seen to affect the performance significantly. From the present study, it is concluded that convergent-divergent vortex finders can be used in place of uniform diameter vortex finders to achieve a better cyclone separator performance.

Keywords: convergent-divergent vortex finder, cyclone separator, discrete phase modeling, Reynolds stress model

Procedia PDF Downloads 158